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Sample records for fabaceae caesalpinioideae structural

  1. The Floral Nectary of Hymenaea stigonocarpa (Fabaceae, Caesalpinioideae): Structural Aspects During Floral Development

    PubMed Central

    Paiva, Elder Antonio Sousa; Machado, Silvia Rodrigues

    2008-01-01

    Background and Aims Considering that few studies on nectary anatomy and ultrastructure are available for chiropterophilous flowers and the importance of Hymenaea stigonocarpa in natural ‘cerrado’ communities, the present study sought to analyse the structure and cellular modifications that take place within its nectaries during the different stages of floral development, with special emphasis on plastid dynamics. Methods For the structural and ultrastructural studies the nectary was processed as per usual techniques and studied under light, scanning and transmission electron microscopy. Histochemical tests were employed to identify the main metabolites on nectary tissue and secretion samples. Key Results The floral nectary consists of the inner epidermis of the hypanthium and vascularized parenchyma. Some evidence indicates that the nectar release occurs via the stomata. The high populations of mitochondria, and their juxtaposition with amyloplasts, seem to be related to energy needs for starch hydrolysis. Among the alterations observed during the secretory phase, the reduction in the plastid stromatic density and starch grain size are highlighted. When the secretory stage begins, the plastid envelope disappears and a new membrane is formed, enclosing this region and giving rise to new vacuoles. After the secretory stage, cellular structures named ‘extrastomatic bodies’ were observed and seem to be related to the nectar resorption. Conclusions Starch hydrolysis contributes to nectar formation, in addition to the photosynthates derived directly from the phloem. In these nectaries, the secretion is an energy-requiring process. During the secretion stage, some plastids show starch grain hydrolysis and membrane rupture, and it was observed that the region previously occupied by this organelle continued to be reasonably well defined, and gave rise to new vacuoles. The extrastomatic bodies appear to be related to the resorption of uncollected nectar. PMID

  2. Microsatellite development for the genus Guibourtia (Fabaceae, Caesalpinioideae) reveals diploid and polyploid species1

    PubMed Central

    Tosso, Felicien; Doucet, Jean-Louis; Kaymak, Esra; Daïnou, Kasso; Duminil, Jérôme; Hardy, Olivier J.

    2016-01-01

    Premise of the study: Nuclear microsatellites (nSSRs) were designed for Guibourtia tessmannii (Fabaceae, Caesalpinioideae), a highly exploited African timber tree, to study population genetic structure and gene flow. Methods and Results: We developed 16 polymorphic nSSRs from a genomic library tested in three populations of G. tessmannii and two populations of G. coleosperma. These nSSRs display three to 14 alleles per locus (mean 8.94) in G. tessmannii. Cross-amplification tests in nine congeneric species demonstrated that the genus Guibourtia contains diploid and polyploid species. Flow cytometry results combined with nSSR profiles suggest that G. tessmannii is octoploid. Conclusions: nSSRs revealed that African Guibourtia species include both diploid and polyploid species. These markers will provide information on the mating system, patterns of gene flow, and genetic structure of African Guibourtia species. PMID:27437170

  3. Microsatellite markers for Senna spectabilis var. excelsa (Caesalpinioideae, Fabaceae)1

    PubMed Central

    López-Roberts, M. Cristina; Barbosa, Ariane R.; Paganucci de Queiroz, Luciano; van den Berg, Cássio

    2016-01-01

    Premise of the study: Senna spectabilis var. excelsa (Fabaceae) is a South and Central American tree of great ecological importance and one of the most common species in several sites of seasonally dry forests. Our goal was to develop microsatellite markers to assess the genetic diversity and structure of this species. Methods and Results: We designed and assessed 53 loci obtained from a microsatellite-enriched library and an intersimple sequence repeat library. Fourteen loci were polymorphic, and they presented a total of 39 alleles in a sample of 61 individuals from six populations. The mean values of observed and expected heterozygosities were 0.355 and 0.479, respectively. Polymorphism information content was 0.390 and the Shannon index was 0.778. Conclusions: Polymorphism information content and Shannon index indicate that at least nine of the 14 microsatellite loci developed are moderate to highly informative, and potentially useful for population genetic studies in this species. PMID:26819856

  4. Intercellular pectic protuberances in Hymenaea stigonocarpa (Fabaceae, Caesalpinioideae): occurrence and functional aspects.

    PubMed

    Paiva, Elder Antônio Sousa; Machado, Sílvia Rodrigues

    2008-04-01

    A study of the anatomy and ultrastructural aspects of leaf mesophyll and floral nectaries of Hymenaea stigonocarpa Mart. ex Hayne revealed the presence of intercellular pectic protuberances (IPPs) linking adjacent cells in both the leaf palisade cells and the secretory parenchyma of the floral nectary. Samples of the middle third of the leaf blade and of floral nectaries in anthesis were collected, fixed, and processed using standard procedures for light, transmission, and scanning electron microscopies. The IPPs of palisade cells of the mesophyll and the secretory parenchyma cells of the floral nectary take the form of scalae or strands, respectively. No evidence of the specific synthesis of these structures was observed, and they are apparently formed by the separation of adjacent cells due to cell expansion, when intercellular spaces develop. The IPPs observed in H. stigonocarpa increase cellular contact and probably act in apoplastic transport.

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

    PubMed

    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.

  6. Enantiostylous types of Cassiinae species (Fabaceae-Caesalpinioideae).

    PubMed

    Almeida, N M; Cotarelli, V M; Souza, D P; Novo, R R; Siqueira Filho, J A; Oliveira, P E; Castro, C C

    2015-05-01

    Species of the subtribe Cassiinae present a wide diversity of floral types. Until recently it was considered that this diversity did not extend to their reproductive mechanisms. However, studies have recorded some variations in the enantiostylous pattern in this plant group. This study aims to investigate the morphological and functional variations of enantiostyly in species of the subtribe Cassiinae. Additionally, it proposes the recognition of enantiostylous types (ET) based on pollen deposition and capture mode. Morphological data were collected in fresh and fixed (alcohol 70%) buds and flowers, and also using photos and rehydrated material from herbarium sheets, for a total of 59 species. The parameters used to establish the ETs were pollination type, nature of pollen deposition on the pollinator body, deposition type, number of petals involved in pollen deposition, and pollen pathway. Morpho-functional features allowed the recognition of seven enantiostylous types (Flexuosa, Cana, Macranthera, Martiana, Amiciella, Repens and Ramosa) that present several levels of complexity. The type Ramosa was the most common and the Cana type was the least common. The types Repens, Martiana and Flexuosa do not have reciprocal pollen deposition, thus species with these types may be considered atypical. The groups resulting from similarity analysis partially coincide with the clades proposed in phylogenetic studies of Cassiinae. The recognition of functional ETs is important for understanding the evolution of reproductive strategies of Cassiinae species, and indicates an interesting line of investigation of enantiostyly in other plant groups.

  7. Population history and gene dispersal inferred from spatial genetic structure of a Central African timber tree, Distemonanthus benthamianus (Caesalpinioideae)

    PubMed Central

    Debout, G D G; Doucet, J-L; Hardy, O J

    2011-01-01

    African rainforests have undergone major distribution range shifts during the Quaternary, but few studies have investigated their impact on the genetic diversity of plant species and we lack knowledge on the extent of gene flow to predict how plant species can cope with such environmental changes. Analysis of the spatial genetic structure (SGS) of a species is an effective method to determine major directions of the demographic history of its populations and to estimate the extent of gene dispersal. This study characterises the SGS of an African tropical timber tree species, Distemonanthus benthamianus, at various spatial scales in Cameroon and Gabon. Displaying a large continuous distribution in the Lower Guinea domain, this is a model species to detect signs of past population fragmentation and recolonization, and to estimate the extent of gene dispersal. Ten microsatellite loci were used to genotype 295 adult trees sampled from eight populations. Three clearly differentiated gene pools were resolved at this regional scale and could be linked to the biogeographical history of the region, rather than to physical barriers to gene flow. A comparison with the distribution of gene pools observed for two other tree species living in the same region invalidates the basic assumption that all species share the same Quaternary refuges and recolonization pathways. In four populations, significant and similar patterns of SGS were detected. Indirect estimates of gene dispersal distances (sigma) obtained for three populations ranged from 400 to 1200 m, whereas neighbourhood size estimates ranged from 50 to 110. PMID:20389306

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

    PubMed Central

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

    2016-01-01

    Background 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. Results 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. Conclusions Recent habitat fragmentation has accelerated genetic divergence. The population genetic structure of G. inflata has been

  9. Fine-scale spatial genetic structure of Dalbergia nigra (Fabaceae), a threatened and endemic tree of the Brazilian Atlantic Forest

    PubMed Central

    de Oliveira Buzatti, Renata Santiago; Ribeiro, Renata Acácio; de Lemos Filho, José Pires; Lovato, Maria Bernadete

    2012-01-01

    The Atlantic Forest is one of the most diverse ecosystems in the world and considered a hotspot of biodiversity conservation. Dalbergia nigra (Fabaceae) is a tree endemic to the Brazilian Atlantic Forest, and has become threatened due to overexploitation of its valuable timber. In the present study, we analyzed the genetic diversity and fine-scale spatial genetic structure of D. nigra in an area of primary forest of a large reserve. All adult individuals (N = 112) were sampled in a 9.3 ha plot, and genotyped for microsatellite loci. Our results indicated high diversity with a mean of 8.6 alleles per locus, and expected heterozygosity equal to 0.74. The co-ancestry coefficients were significant for distances among trees up to 80 m. The Sp value was equal to 0.017 and indirect estimates of gene dispersal distances ranged from 89 to 144 m. No strong evidence of bottleneck or effects of human-disturbance was found. This study highlights that long-term efforts to protect a large area of Atlantic Forest have been effective towards maintaining the genetic diversity of D. nigra. The results of this study are important towards providing a guide for seed collection for ex-situ conservation and reforestation programmes of this threatened species. PMID:23271946

  10. Effect of clonal reproduction on genetic structure in Pentaclethra macroloba (Fabaceae: Mimosoideae).

    PubMed

    Gaddis, Keith D; Zukin, Helen L; Dieterich, Inca A; Braker, Elizabeth; Sork, Victoria L

    2014-06-01

    The existence of monodominant forests on well-drained soils in tropical regions has been widely reported. Such forests most likely result from a combination of both ecological and evolutionary factors. Under conditions of high seed and seedling mortality, vegetative reproduction could create a reproductive advantage leading to forest dominance, and profoundly affect the distribution of genetic variation in a clonal species. We investigated these effects in a low diversity forest site in Northeastern Costa Rica dominated by the species Pentaclethra macroloba, which sprouts from the root mass of fallen trees and from snapped trunks. We examined the population structure of juvenile P. macroloba growing in different soil types and across an elevational gradient. Using seven molecular markers, we genotyped 173 juvenile P. macroloba from 18 plots (six plots in seasonally inundated swamps, and 12 plots in upland non-swamp) spanning 50-300m in elevation at La Selva Biological Station and the adjacent Reserva Ecológica Bijagual in Northeastern Costa Rica. We answered two specific questions: (1) How extensive is clonal reproduction? and (2) what is the distribution of genetic diversity and structure? We found that clonal reproduction occurred exclusively within inundated swamp areas. However, there was no significant difference between genetic diversity measures in swamp and non-swamp plots, which were both generally low when compared with other tropical forest species. Genetic structure was significant across all plots (F(ST) = -0.109). However, genetic structure among swamp plots (F(ST) = 0.128) was higher than among non-swamp upland plots (F(ST) = 0.093). Additionally, spatial autocorrelation among individuals within non-swamp upland plots was significant from the 25 to 100m spatial scale, but not within swamp plots. The degree of overall genetic structure we found in P. macroloba is high for a tropical forest tree. The incidence of clonal reproduction is a contributing

  11. Effect of clonal reproduction on genetic structure in Pentaclethra macroloba (Fabaceae: Mimosoideae).

    PubMed

    Gaddis, Keith D; Zukin, Helen L; Dieterich, Inca A; Braker, Elizabeth; Sork, Victoria L

    2014-06-01

    The existence of monodominant forests on well-drained soils in tropical regions has been widely reported. Such forests most likely result from a combination of both ecological and evolutionary factors. Under conditions of high seed and seedling mortality, vegetative reproduction could create a reproductive advantage leading to forest dominance, and profoundly affect the distribution of genetic variation in a clonal species. We investigated these effects in a low diversity forest site in Northeastern Costa Rica dominated by the species Pentaclethra macroloba, which sprouts from the root mass of fallen trees and from snapped trunks. We examined the population structure of juvenile P. macroloba growing in different soil types and across an elevational gradient. Using seven molecular markers, we genotyped 173 juvenile P. macroloba from 18 plots (six plots in seasonally inundated swamps, and 12 plots in upland non-swamp) spanning 50-300m in elevation at La Selva Biological Station and the adjacent Reserva Ecológica Bijagual in Northeastern Costa Rica. We answered two specific questions: (1) How extensive is clonal reproduction? and (2) what is the distribution of genetic diversity and structure? We found that clonal reproduction occurred exclusively within inundated swamp areas. However, there was no significant difference between genetic diversity measures in swamp and non-swamp plots, which were both generally low when compared with other tropical forest species. Genetic structure was significant across all plots (F(ST) = -0.109). However, genetic structure among swamp plots (F(ST) = 0.128) was higher than among non-swamp upland plots (F(ST) = 0.093). Additionally, spatial autocorrelation among individuals within non-swamp upland plots was significant from the 25 to 100m spatial scale, but not within swamp plots. The degree of overall genetic structure we found in P. macroloba is high for a tropical forest tree. The incidence of clonal reproduction is a contributing

  12. Genetic and clonal diversity of the endemic ant-plant Humboldtia brunonis (Fabaceae) in the Western Ghats of India.

    PubMed

    Dev, Suma A; Shenoy, Megha; Borges, Renee M

    2010-06-01

    Humboldtia brunonis (Fabaceae, Caesalpinioideae) is a dominant self-incompatible ant-plant or myrmecophyte, growing as an understorey tree in high-density patches. It is endemic to the biodiversity hotspot of the southern Western Ghats of India and, besides ants, harbours many endemic invertebrate taxa, such as bees that pollinate it as well as arboreal earthworms, within swollen hollow stem internodes called domatia. Using inter simple sequence repeat (ISSR) markers, three geographically separated populations were found to be multiclonal, characterized by high levels of clonal diversity. Values for the Simpson diversity index ranged between 0.764 and 0.964, and for Fager's evenness index between 0.00 and 0.036 for neighbourhoods within populations. This myrmecophyte was found to combine sexual recruitment (66.7%) and clonal production (33.3%) as methods of reproduction. Moderate amounts of genetic diversity at the species level were observed, with 52.63% polymorphism, and moderate values of Shannon's diversity index (0.1895) as well as of Nei's gene diversity (0.1186). In each population, observed genotypic diversity was significantly lower than expected, indicating significant genetic structure. Neighbour-joining trees demonstrated that Agumbe, which is the most northern population examined and geographically twice as far away from the other two populations, grouped separately and with larger bootstrap support from a larger cluster consisting of the Sampaji and Solaikolli populations, which are closer to each other geographically. Some neighbourhoods within each population showed spatial genetic structure even at small spatial scales of less than 5 m. A combination of clonality and short-distance pollen movement by small pollinating bees (Braunsapis puangensis) coupled with primary ballistic seed dispersal, and possible secondary seed dispersal by rodents, may contribute to spatial genetic structure at such small scales. The clonality of H. brunonis may be a

  13. Genetic diversity and mating system of Copaifera langsdorffii (Leguminosae/Caesalpinioideae).

    PubMed

    Gonela, A; Sebbenn, A M; Soriani, H H; Mestriner, M A; Martinez, C A; Alzate-Marin, A L

    2013-02-27

    Copaifera langsdorffii, locally known as copaíba, is a valuable tropical tree with medicinal properties of its oil. We studied the genetic variation, genetic structure, and the mating system of trees in stands of C. langsdorffii (Leguminosae/Caesalpinioideae) located in an extensive area between the Pardo and Mogi-Guaçu basins in São Paulo State, Brazil, and their offspring, conserved in an ex situ germplasm bank at the University of São Paulo in Ribeirão Preto, SP, Brazil, using six microsatellite loci. Leaves were collected from 80 seed trees and from 259 offspring and their DNA extracted. A total of 140 and 175 alleles were found in the seed trees and their offspring, respectively. Low genetic differentiation was observed between stands, indicating intense gene flow due to efficient pollen dispersion vectors. An estimation of the outcrossing rate showed that these stands are outcrossed (tm = 0.98, P > 0.05). The mean variance of the effective population size of each family in two of the stands was 3.69 and 3.43, while the total effective population size retained in the germplasm bank was between 81 and 96. The paternity correlation was low, ranging from 0.052 to 0.148, demonstrating that the families implanted in this germplasm bank are composed predominantly of half-sibs.

  14. Logging impacts on forest structure and seedling dynamics in a Prioria copaifera (Fabaceae) dominated tropical rain forest (Talamanca, Costa Rica).

    PubMed

    Valverde-Barrantes, Oscar J; Rocha, Oscar J

    2014-03-01

    The factors that determine the existence of tropical forests dominated by a single species (monodominated forests) have been the subject of debate for a long time. It has been hypothesized that the low frequency of disturbances in monodominated forests and the tolerance to shade of the monodominant species are two important factors explaining the prolonged dominance of a single species. We determined the role of these two factors by examining the effects of logging activities on the floristic composition and seedling dynamics in a Prioria copaifera dominated forest in Southeastern Costa Rica. We determined the floristic composition for trees > or = 2.5cm DBH and the associated recruitment, survival and mortality of tree canopy seedlings in two sites logged two (L-02) and 12 years (L-12) prior to sampling and an unlogged forest (ULF). Our results showed that L-02 stands had lower species richness (25 species) than the L-12 and ULF stands (49 and 46 species, respectively). As expected, we found significant logging effects on the canopy structure of the altered forests, particularly when comparing the L-02 and the ULF stands. Seedling density was higher in ULF (0.96 seedlings/ m2) than in the L-02 and L-12 stands (0.322 and 0.466 seedlings/m2, respectively). However, seedling mortality was higher in the ULF stands (54%) than in the L-02 (26%) and L-12 (15%) stands. P. macroloba in L-02 was the only species with abundant regeneration under P. copaifera in L-02 stand, where it accounted for 35% of the seedlings. Despite the reduction in seedling abundance observed after logging, P. copaifera seems to maintain large seedling populations in these forests, suggesting that this species maintains its dominance after logging disturbances. Our findings challenge the hypothesis that the regeneration of monodominant species is not likely to occur under heavily disturbed canopy conditions. PMID:24912364

  15. Logging impacts on forest structure and seedling dynamics in a Prioria copaifera (Fabaceae) dominated tropical rain forest (Talamanca, Costa Rica).

    PubMed

    Valverde-Barrantes, Oscar J; Rocha, Oscar J

    2014-03-01

    The factors that determine the existence of tropical forests dominated by a single species (monodominated forests) have been the subject of debate for a long time. It has been hypothesized that the low frequency of disturbances in monodominated forests and the tolerance to shade of the monodominant species are two important factors explaining the prolonged dominance of a single species. We determined the role of these two factors by examining the effects of logging activities on the floristic composition and seedling dynamics in a Prioria copaifera dominated forest in Southeastern Costa Rica. We determined the floristic composition for trees > or = 2.5cm DBH and the associated recruitment, survival and mortality of tree canopy seedlings in two sites logged two (L-02) and 12 years (L-12) prior to sampling and an unlogged forest (ULF). Our results showed that L-02 stands had lower species richness (25 species) than the L-12 and ULF stands (49 and 46 species, respectively). As expected, we found significant logging effects on the canopy structure of the altered forests, particularly when comparing the L-02 and the ULF stands. Seedling density was higher in ULF (0.96 seedlings/ m2) than in the L-02 and L-12 stands (0.322 and 0.466 seedlings/m2, respectively). However, seedling mortality was higher in the ULF stands (54%) than in the L-02 (26%) and L-12 (15%) stands. P. macroloba in L-02 was the only species with abundant regeneration under P. copaifera in L-02 stand, where it accounted for 35% of the seedlings. Despite the reduction in seedling abundance observed after logging, P. copaifera seems to maintain large seedling populations in these forests, suggesting that this species maintains its dominance after logging disturbances. Our findings challenge the hypothesis that the regeneration of monodominant species is not likely to occur under heavily disturbed canopy conditions.

  16. Short Communication Mendelian inheritance, linkage, and genotypic disequilibrium in microsatellite loci of Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae-Caesalpinioideae).

    PubMed

    Moraes, M A; Kubota, T Y K; Silva, E C B; Silva, A M; Cambuim, J; Moraes, M L T; Furlani Junior, E; Sebbenn, A M

    2016-01-01

    Hymenaea stigonocarpa is a deciduous and monoecious Neotropical tree species pollinated by bats. Due to overexploitation and habitat destruction, the population size has drastically diminished in nature. No previous study has investigated Mendelian inheritance, linkage, and genotypic disequilibrium in the available microsatellite markers in this species. So, our aim was to estimate these parameters using six microsatellite loci in a sample of 470 adults and 219 juveniles from two populations of H. stigonocarpa. In addition, 30 seeds per tree from 35 seed-trees were collected. Each seed was kept record of the seed-trees and fruit origin. Based on the six microsatellite loci, we found that only 10.6% of the cases showed significant deviations from Mendelian segregation and 15.3% showed linkage. We detected no evidence of genotypic disequilibrium between the loci in the adult trees or juveniles. Thus, our results suggest that these loci can be used with great accuracy in future genetic analyses of H. stigonocarpa populations. PMID:27525897

  17. Short Communication Mendelian inheritance, linkage, and genotypic disequilibrium in microsatellite loci of Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae-Caesalpinioideae).

    PubMed

    Moraes, M A; Kubota, T Y K; Silva, E C B; Silva, A M; Cambuim, J; Moraes, M L T; Furlani Junior, E; Sebbenn, A M

    2016-07-29

    Hymenaea stigonocarpa is a deciduous and monoecious Neotropical tree species pollinated by bats. Due to overexploitation and habitat destruction, the population size has drastically diminished in nature. No previous study has investigated Mendelian inheritance, linkage, and genotypic disequilibrium in the available microsatellite markers in this species. So, our aim was to estimate these parameters using six microsatellite loci in a sample of 470 adults and 219 juveniles from two populations of H. stigonocarpa. In addition, 30 seeds per tree from 35 seed-trees were collected. Each seed was kept record of the seed-trees and fruit origin. Based on the six microsatellite loci, we found that only 10.6% of the cases showed significant deviations from Mendelian segregation and 15.3% showed linkage. We detected no evidence of genotypic disequilibrium between the loci in the adult trees or juveniles. Thus, our results suggest that these loci can be used with great accuracy in future genetic analyses of H. stigonocarpa populations.

  18. Microsatellite development and flow cytometry in the African tree genus Afzelia (Fabaceae, Caesalpinioideae) reveal a polyploid complex1

    PubMed Central

    Donkpegan, Armel S. L.; Doucet, Jean-Louis; Dainou, Kasso; Hardy, Olivier J.

    2015-01-01

    • Premise of the study: Microsatellites were developed in the vulnerable African rainforest tree Afzelia bipindensis to investigate gene flow patterns. • Methods and Results: Using 454 GS-FLX technique, 16 primer sets were identified and optimized, leading to 11 polymorphic and readable markers displaying each six to 25 alleles in a population. Up to four alleles per individual were found in each of the loci, without evidence of fixed heterozygosity, suggesting an autotetraploid genome. Cross-amplification succeeded for all loci in the African rainforest species A. pachyloba and A. bella, which appeared tetraploid, and for most loci in the African woodland species A. africana and A. quanzensis, which appeared diploid, but failed in the Asian species A. xylocarpa. Flow cytometry confirmed the suspected differences in ploidy. • Conclusions: African Afzelia species are diploid or tetraploid, a situation rarely documented in tropical trees. These newly developed microsatellites will help in the study of their mating system and gene flow patterns. PMID:25606356

  19. Optimization of DNA extraction from fresh leaf tissues of Melanoxylon brauna (Fabaceae).

    PubMed

    Borges, D B; Amorim, M B; Waldschmidt, A M; Mariano-Neto, E; Vivas, C V; Pereira, D G

    2012-05-22

    Melanoxylon brauna (Fabaceae - Caesalpinioideae) is an endemic and valuable hardwood tree species in the Brazilian Atlantic rainforest; it is comparable to African ebony wood. We tested three protocols of DNA extraction based on the citrimonium bromide (CTAB) method and evaluated the quantity, purity and integrity of the DNA. We also determined whether these procedures interfere with PCR amplification in order to develop a protocol for M. brauna. We found that the quality and integrity of DNA were improved with the use of proteinase K in the extraction buffer and by modifications in the centrifugation speed. The lowest concentration of DNA was obtained with Doyle and Doyle's protocol (5.42 ng/μL). Ferreira and Grattapaglia's protocol modified for M. brauna provided the most DNA (36.89 ng/μL) and the highest quality DNA (purity ratio of 1.80 nm). The original Ferreira and Grattapaglia protocol provided 13.42 ng/μL DNA; however, the purity ratio (1.44 nm) indicates protein contamination. PCR results showed that Ferreira and Grattapaglia's protocol modified for M. brauna gave satisfactory quantity and purity of DNA for molecular studies.

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

    PubMed

    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.

  1. Leaf volatile compounds and the distribution of ant patrollingin an ant-plant protection mutualism: Preliminary results on Leonardoxa (Fabaceae: Caesalpinioideae) and Petalomyrmex(Formicidae: Formicinae)

    NASA Astrophysics Data System (ADS)

    Brouat, Carine; McKey, Doyle; Bessière, Jean-Marie; Pascal, Laurence; Hossaert-McKey, Martine

    2000-12-01

    While observations suggest that plant chemicals could be important in maintaining the specificity and permitting the functioning of ant-plant symbioses, they have been little studied. We report here the strongest evidence yet for chemical signalling between ants and plants in a specific ant-plant protection symbiosis. In the mutualism between Leonardoxa africana subsp. africana and Petalomyrmex phylax, ants continuously patrol young leaves, which are vulnerable to attacks by phytophagous insects. We provide experimental evidence for chemical mediation of ant attraction to young leaves in this system. By a comparative analysis of the related non-myrmecophytic tree L. africana subsp. gracilicaulis, we identify likely candidates for attractant molecules, and suggest they may function not only as signals but also as resources. We also propose hypotheses on the evolutionary origin of these plant volatiles, and of the responses to them by mutualistic ants.

  2. Morphological analyses suggest a new taxonomic circumscription for Hymenaea courbaril L. (Leguminosae, Caesalpinioideae).

    PubMed

    Souza, Isys Mascarenhas; Funch, Ligia Silveira; de Queiroz, Luciano Paganucci

    2014-01-01

    Hymenaea is a genus of the Resin-producing Clade of the tribe Detarieae (Leguminosae: Caesalpinioideae) with 14 species. Hymenaea courbaril is the most widespread species of the genus, ranging from southern Mexico to southeastern Brazil. As currently circumscribed, Hymenaea courbaril is a polytypic species with six varieties: var. altissima, var. courbaril, var. longifolia, var. stilbocarpa, var. subsessilis, and var. villosa. These varieties are distinguishable mostly by traits related to leaflet shape and indumentation, and calyx indumentation. We carried out morphometric analyses of 14 quantitative (continuous) leaf characters in order to assess the taxonomy of Hymenaea courbaril under the Unified Species Concept framework. Cluster analysis used the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) based on Bray-Curtis dissimilarity matrices. Principal Component Analyses (PCA) were carried out based on the same morphometric matrix. Two sets of Analyses of Similarity and Non Parametric Multivariate Analysis of Variance were carried out to evaluate statistical support (1) for the major groups recovered using UPGMA and PCA, and (2) for the varieties. All analyses recovered three major groups coincident with (1) var. altissima, (2) var. longifolia, and (3) all other varieties. These results, together with geographical and habitat information, were taken as evidence of three separate metapopulation lineages recognized here as three distinct species. Nomenclatural adjustments, including reclassifying formerly misapplied types, are proposed.

  3. Morphological analyses suggest a new taxonomic circumscription for Hymenaea courbaril L. (Leguminosae, Caesalpinioideae)

    PubMed Central

    Souza, Isys Mascarenhas; Funch, Ligia Silveira; de Queiroz, Luciano Paganucci

    2014-01-01

    Abstract Hymenaea is a genus of the Resin-producing Clade of the tribe Detarieae (Leguminosae: Caesalpinioideae) with 14 species. Hymenaea courbaril is the most widespread species of the genus, ranging from southern Mexico to southeastern Brazil. As currently circumscribed, Hymenaea courbaril is a polytypic species with six varieties: var. altissima, var. courbaril, var. longifolia, var. stilbocarpa, var. subsessilis, and var. villosa. These varieties are distinguishable mostly by traits related to leaflet shape and indumentation, and calyx indumentation. We carried out morphometric analyses of 14 quantitative (continuous) leaf characters in order to assess the taxonomy of Hymenaea courbaril under the Unified Species Concept framework. Cluster analysis used the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) based on Bray-Curtis dissimilarity matrices. Principal Component Analyses (PCA) were carried out based on the same morphometric matrix. Two sets of Analyses of Similarity and Non Parametric Multivariate Analysis of Variance were carried out to evaluate statistical support (1) for the major groups recovered using UPGMA and PCA, and (2) for the varieties. All analyses recovered three major groups coincident with (1) var. altissima, (2) var. longifolia, and (3) all other varieties. These results, together with geographical and habitat information, were taken as evidence of three separate metapopulation lineages recognized here as three distinct species. Nomenclatural adjustments, including reclassifying formerly misapplied types, are proposed. PMID:25009440

  4. Nodulation in Dimorphandra wilsonii Rizz. (Caesalpinioideae), a Threatened Species Native to the Brazilian Cerrado

    PubMed Central

    Fonseca, Márcia Bacelar; Peix, Alvaro; de Faria, Sergio Miana; Mateos, Pedro F.; Rivera, Lina P.; Simões-Araujo, Jean L.; França, Marcel Giovanni Costa; dos Santos Isaias, Rosy Mary; Cruz, Cristina; Velázquez, Encarna; Scotti, Maria Rita; Sprent, Janet I.; James, Euan K.

    2012-01-01

    The threatened caesalpinioid legume Dimorphandra wilsonii, which is native to the Cerrado biome in Brazil, was examined for its nodulation and N2-fixing ability, and was compared with another, less-threatened species, D. jorgei. Nodulation and potential N2 fixation was shown on seedlings that had been inoculated singly with five bradyrhizobial isolates from mature D. wilsonii nodules. The infection of D. wilsonii by two of these strains (Dw10.1, Dw12.5) was followed in detail using light and transmission electron microscopy, and was compared with that of D. jorgei by Bradyrhizobium strain SEMIA6099. The roots of D. wilsonii were infected via small transient root hairs at 42 d after inoculation (dai), and nodules were sufficiently mature at 63 dai to express nitrogenase protein. Similar infection and nodule developmental processes were observed in D. jorgei. The bacteroids in mature Dimorphandra nodules were enclosed in plant cell wall material containing a homogalacturonan (pectic) epitope that was recognized by the monoclonal antibody JIM5. Analysis of sequences of their rrs (16S rRNA) genes and their ITS regions showed that the five D. wilsonii strains, although related to SEMIA6099, may constitute five undescribed species of genus Bradyrhizobium, whilst their nodD and nifH gene sequences showed that they formed clearly separated branches from other rhizobial strains. This is the first study to describe in full the N2-fixing symbiotic interaction between defined rhizobial strains and legumes in the sub-family Caesalpinioideae. This information will hopefully assist in the conservation of the threatened species D. wilsonii. PMID:23185349

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

    PubMed Central

    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

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

    PubMed

    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.

  7. Fatty acid profiles of some Fabaceae seed oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  8. Insect herbivores associated with an evergreen tree Goniorrhachis marginata Taub. (Leguminosae: Caesalpinioideae) in a tropical dry forest.

    PubMed

    Silva, J O; Neves, F S

    2014-08-01

    Goniorrhachis marginata Taub. (Leguminosae: Caesalpinioideae) is a tree species found in Brazilian tropical dry forests that retain their leaves during the dry season. That being, we addressed the following question: i) How do insect diversity (sap-sucking and chewing), leaf herbivory and defensive traits (tannin and leaf sclerophylly) vary on the evergreen tree species G. marginata between seasons? The abundance of sap-sucking insects was higher in the dry season than in the rainy season. However, we did not verify any difference in the species richness and abundance of chewing insects between seasons. Leaf herbivory was higher in the rainy season, whereas leaf sclerophylly was higher in the dry season. However, herbivory was not related to sclerophylly. Insect herbivores likely decrease their folivory activity during the dry season due to life history patterns or changes in behaviour, possibly entering diapause or inactivity during this period. Therefore, G. marginata acts as a likely keystone species, serving as a moist refuge for the insect fauna during the dry season in tropical dry forest, and the presence of this evergreen species is crucial to conservation strategies of this threatened ecosystem.

  9. Flavonoids from Erythrina vogelii (Fabaceae) of Cameroon.

    PubMed

    Ali, Muhammad Imran; Ahmed, Zeeshan; Waffo, Alain Francois Kamdem; Ali, Muhammad Shaiq

    2010-06-01

    A new flavone, vogeol, and a new isoflavone, vogliiol, have been isolated from Erythrina vogelii, a Cameroonian medicinal plant, along with seven known constituents (salvigenin, carpachromene, euchrenone b10, scandenone, 5,4'-dihydroxy-8-(3"-methylbut-2"-enyl)-2'''-(4'''-hydroxy-4'''-methylethyl)-furano-[4''',5''':6,7] isoflavone, erythrivarone C, and 5,7,4'-trihydroxy-6-[3"-methylbut-3"-enyl]-flavone). Their structures were elucidated by spectroscopic methods. PMID:20614816

  10. A new isocoumarin from Cajanus cajan (Fabaceae).

    PubMed

    Rodrigues, Virginia F; Oliveira, Rodrigo R; Vega, Maria Raquel G

    2014-04-01

    A new isocoumarin, 3-phenyl-8-hydroxy-6-methoxy-5-gamma,gamma-dimethylallyl-isocoumarin, named cajavilmina (1) and eight known compounds: a-amirenone (2), beta-amirenone (3), lupenone (4), 5-hydroxy-7-methoxydihydroflavone (5), longistilin C (6), 3-hydroxy-5-methoxystilbene (7), beta-sitosterol (8) and stigmasterol (9) were identified in a dichloromethane fraction from Cajanus cajan leaves. Structures were elucidated by analysis of spectral data, mainly those afforded by 1H, NOEDIFF and 13C NMR (1D and 2D NMR HMQC, HMBC and COSY) and mass spectra. PMID:24868865

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

    PubMed Central

    2015-01-01

    Abstract 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. PMID:25829859

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

    PubMed

    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. PMID:21194241

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

    PubMed

    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.

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

    PubMed

    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.

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

    PubMed

    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.

  16. Evaluation of the impact of functional diversification on Poaceae, Brassicaceae, Fabaceae, and Pinaceae alcohol dehydrogenase enzymes.

    PubMed

    Thompson, Claudia E; Fernandes, Cláudia L; de Souza, Osmar Norberto; de Freitas, Loreta B; Salzano, Francisco M

    2010-05-01

    The plant alcohol dehydrogenases (ADHs) have been intensively studied in the last years in terms of phylogeny and they have been widely used as a molecular marker. However, almost no information about their three-dimensional structure is available. Several studies point to functional diversification of the ADH, with evidence of its importance, in different organisms, in the ethanol, norepinephrine, dopamine, serotonin, and bile acid metabolism. Computational results demonstrated that in plants these enzymes are submitted to a functional diversification process, which is reinforced by experimental studies indicating distinct enzymatic functions as well as recruitment of specific genes in different tissues. The main objective of this article is to establish a correlation between the functional diversification occurring in the plant alcohol dehydrogenase family and the three-dimensional structures predicted for 17 ADH belonging to Poaceae, Brassicaceae, Fabaceae, and Pinaceae botanical families. Volume, molecular weight and surface areas are not markedly different among them. Important electrostatic and pI differences were observed with the residues responsible for some of them identified, corroborating the function diversification hypothesis. These data furnish important background information for future specific structure-function and evolutionary investigations.

  17. Karyotype analyses of ten sections of Trigonella (Fabaceae).

    PubMed

    Martin, E; Akan, H; Ekici, M; Aytac, Z

    2011-01-01

    Karyotypes of ten sections of genus Trigonella Linnaeus, 1753 (Fabaceae) from Turkey were investigated. Somatic chromosome numbers of examined species were determined as 2n=14 and 16. The karyotype analyses of the species were carried out and somatic chromosome numbers of Trigonella plicata Boiss., 1872, Trigonella brachycarpa (Fisch.) Moris, 1833, Trigonella rostrata Boiss., 1872, Trigonella lunata Boiss., 1843, Trigonella isthmocarpa Boiss. et Balansa 1856, Trigonella rhytidocarpa Boiss. et Balansa, 1859, Trigonella spicata Sibth. et Sm., 1813, Trigonella cephalotes Boiss. et Balansa 1856, Trigonella capitata Boiss., 1843 and Trigonella gladiata Steven, 1808 were reported for the first time. Two pairs of satellite metaphase chromosomes were observed in Trigonella cariensis Boiss., 1843 and one pair in Trigonella lunata.Moreover, 2 B-chromosomes were found only in Trigonella procumbens Rchb., 1830 among all studied species. The aims of this study are to provide karyological data for a significant pool of the taxa, to show differences among them in the number, size and morphology of somatic chromosomes, to verify previous reports or represent numbers which are different from those cited previously.

  18. Nutritional potential of biochemical components in Galactia longifolia Benth. (Fabaceae).

    PubMed

    Thangadurai, D; Viswanathan, M B; Ramesh, N

    2001-04-01

    Seeds of Galactia longifolia Benth. (Fabaceae), locally known as Kaattukollu in Tamil language, used as food by Malayali tribals in the Kolli hills of Namakkal District, Tamil Nadu in South India were analysed for proximate composition, total (true) seed proteins, amino acid composition, fatty acid composition, minerals and antinutritional factors. Crude protein, crude fat, ash and nitrogen free extractives constitute 25.56%, 6.18%, 5.12% and 56.15%, respectively. The caloric value of 100 g dry matter of seed material is 1,601 KJ. The essential amino acids, tryptophan, leucine + isoleucine, arginine and threonine are present relatively in large quantities. The unsaturated fatty acids constitute more than 60%. The seeds are very rich in potassium, magnesium, calcium and phosphorus. Antinutritional factors such as total free phenols, tannins, L-DOPA, hydrogen cyanide and phytic acid is present in minute quantities. The seed meal is consumed after eliminating all the antinutritional factors using the conventional method of soaking seeds in water, boiling with water and decanting for four times by Malayali tribals.

  19. Antiprotozoal activities of Millettia richardiana (Fabaceae) from Madagascar.

    PubMed

    Rajemiarimiraho, Manitriniaina; Banzouzi, Jean-Théophile; Nicolau-Travers, Marie-Laure; Ramos, Suzanne; Cheikh-Ali, Zakaria; Bories, Christian; Rakotonandrasana, Olga L; Rakotonandrasana, Stéphane; Andrianary, Philippe Antoine; Benoit-Vical, Françoise

    2014-01-01

    With at least 60% of the Millettia species (Fabaceae) being in medicinal use, we found it relevant to assess the potential antiprotozoal and antifungal activities of Millettia richardiana. Water and methanol crude extracts of the stem barks from M. richardiana and the six fractions resulting from the fractionation of the methanol extract were tested. The dichloromethane extracted fraction showed the best in vitro antiprotozoal activities (IC50=5.8 μg/mL against Plasmodium falciparum, 11.8 μg/mL against Leishmania donovani and 12.8 μg/mL against Trypanosoma brucei brucei) as well as low cytotoxicity on several cell lines. The phytochemical analysis showed this selected fraction to be rich in terpenoids and alkaloids, which could explain its antiparasitic activity. A phytochemical study revealed the presence of lonchocarpenin, betulinic acid, β-amyrin, lupeol, palmitic acid, linoleic acid and stearic acid, among which betulinic acid and lupeol could be the compounds responsible of these antiprotozoal activities. By contrast, neither the crude extracts nor the fractions showed antifungal activity against Candida. These results confirm the importance of the genus Millettia in Malagasy ethnomedicine, its potential use in antiparasitic therapy, and the interest of developing a sustainable exploitation of this plant. Moreover, both molecules betulinic acid and lupeol appeared as very relevant molecules for their antiprotozoal properties. PMID:24705564

  20. Development of 23 polymorphic microsatellite loci in invasive silver wattle, Acacia dealbata (Fabaceae)1

    PubMed Central

    Guillemaud, Thomas; Broadhurst, Linda; Legoff, Isabelle; Henery, Martin; Blin, Aurélie; Ducatillion, Catherine; Ferrando, Nathalie; Malausa, Thibaut

    2015-01-01

    Premise of the study: Microsatellite markers were developed for silver wattle, Acacia dealbata (Fabaceae), which is both an ornamental and an invasive weed species. It is native to southeastern Australia and invasive in Europe, Africa, Asia, and the Americas. Methods and Results: The pyrosequencing of a microsatellite-enriched genomic DNA library of A. dealbata produced 33,290 sequences and allowed the isolation of 201 loci with a minimum of seven repeats of microsatellite motifs. Amplification tests led to the setup of two multiplex PCR mixes allowing the amplification of 21 loci. The polymorphism of these markers was evaluated on a sample of 32 individuals collected in southeastern Australia. The number of alleles and the expected heterozygosity varied between two and 11, and between 0.11 and 0.88, respectively. Conclusions: The level of polymorphism of this set of 23 microsatellites is large enough to provide valuable information on the genetic structure and the invasion history of A. dealbata. PMID:25995979

  1. Development and characterization of 14 microsatellite markers for Indigofera pseudotinctoria (Fabaceae)1

    PubMed Central

    Otao, Tomoko; Kobayashi, Tatsuaki; Uehara, Koichi

    2016-01-01

    Premise of the study: Microsatellite markers can be used to evaluate population structure and genetic diversity in native populations of Indigofera pseudotinctoria (Fabaceae) and assess genetic disturbance caused by nonnative plants of the same species. Methods and Results: We developed 14 markers for I. pseudotinctoria using next-generation sequencing and applied them to test two native populations, totaling 77 individuals, and a transplanted population, imported from a foreign country, of 17 individuals. The mean number of alleles was 3.310, observed heterozygosity was 0.242, and expected heterozygosity was 0.346. The fixation index in the transplanted population was 0.469, which was higher than in the native populations (0.154 and 0.158). In addition, the transplanted population contains one allele that is not shared by the native population. Conclusions: Microsatellite markers can be useful for evaluating genetic diversity within and between populations and for studying population genetics in I. pseudotinctoria and related species. PMID:27144104

  2. Demographic history and the low genetic diversity in Dipteryx alata (Fabaceae) from Brazilian Neotropical savannas

    PubMed Central

    Collevatti, R G; Telles, M P C; Nabout, J C; Chaves, L J; Soares, T N

    2013-01-01

    Genetic effects of habitat fragmentation may be undetectable because they are generally a recent event in evolutionary time or because of confounding effects such as historical bottlenecks and historical changes in species' distribution. To assess the effects of demographic history on the genetic diversity and population structure in the Neotropical tree Dipteryx alata (Fabaceae), we used coalescence analyses coupled with ecological niche modeling to hindcast its distribution over the last 21 000 years. Twenty-five populations (644 individuals) were sampled and all individuals were genotyped using eight microsatellite loci. All populations presented low allelic richness and genetic diversity. The estimated effective population size was small in all populations and gene flow was negligible among most. We also found a significant signal of demographic reduction in most cases. Genetic differentiation among populations was significantly correlated with geographical distance. Allelic richness showed a spatial cline pattern in relation to the species' paleodistribution 21 kyr BP (thousand years before present), as expected under a range expansion model. Our results show strong evidences that genetic diversity in D. alata is the outcome of the historical changes in species distribution during the late Pleistocene. Because of this historically low effective population size and the low genetic diversity, recent fragmentation of the Cerrado biome may increase population differentiation, causing population decline and compromising long-term persistence. PMID:23591520

  3. Air quality biomonitoring through pollen viability of Fabaceae.

    PubMed

    Duro, Anna; Piccione, Vincenzo; Zampino, Daniela

    2013-05-01

    In this study, pollen viability and germination of three plant species, Cercis siliquastrum L., Robinia pseudoacacia L., and Spartium junceum L., belonging to the Fabaceae family, was evaluated in sites with different intensity of road traffic, constantly monitored with continuous analysers for air pollutants (carbon monoxide (CO), sulphur dioxide (SO(2)), and nitrogen dioxide (NO(2))) by the Municipality of Catania. Two sites, in which road traffic was absent, were selected, too. The percentages of viable pollen by 2,3,5-trypheniltetrazolium chloride (TTC) test ranged from 59.0 to 90.2 % in C. siliquastrum, from 61.5 to 83.5 % in S. junceum and from 67.5 to 84.3 % in R. pseudoacacia. The percentages of germination varied from 41.0 to 72.7 % in C. siliquastrum, from 42.0 to 64.7 % in S. junceum and from 38.3 to 66.3 % in R. pseudoacacia. The highest percentages of viable pollens were found in no-road traffic stations by either TTC or germination tests, while the lowest values were detected in a site characterised by heavy road traffic. In the monitored period (2007-2009), pollen viability, germinability and tube length of C. siliquastrum resulted in a significant negative correlation to CO, SO(2) and NO(2), whereas data from TTC and germination tests on S. junceum and R. pseudoacacia pollens were not well correlated to air pollutants. The results showed that pollen viability, germination and tube growth in C. siliquastrum were affected by air pollution. S. junceum and R. pseudoacacia were not very influenced by air pollutants, suggesting a different pollen sensitivity of these species.

  4. A new species Megabruchidius sophorae (Coleoptera, Bruchidae), feeding on seeds of Styphnolobium (Fabaceae) new to Bruchidae.

    PubMed

    Tuda, Midori; Morimoto, Katsura

    2004-01-01

    A new species Megabruchidiussophorae (Insecta, Coleoptera) is described from Japan (Honshu). The larval host of this bruchid is the seeds of the tree legume 'enju', or chinese scholar tree, Styphnolobium japonicum (a senior synonym of Sophora japonica), which is a new host genus to Bruchidae. Styphnolobium is positioned basally in molecular phylogeny of the leguminous subfamily Papilionoideae. Other members of Megabruchidius are known to feed on Gleditsia, the tree legumes that belong to the most ancestral subfamily Caesalpinioideae. Therefore, Megabruchidius utilizes ancestral groups of legumes as its host plants. Megabruchidius has been inferred to be ancestral, based on its behavior. The character state of the host for this third Megabruchidius species supports that the genus is ancestral, at least in the subfamily Bruchinae. We also reviewed the genera closely related to Megabruchidius, i.e., Bruchidius and Sulcobruchus in Bruchidini, and wrote a key to the species in the genus Megabruchidius. PMID:14745110

  5. Discovery and characterization of novel cyclotides originated from chimeric precursors consisting of albumin-1 chain a and cyclotide domains in the Fabaceae family.

    PubMed

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

    2011-07-01

    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

  6. Discovery and characterization of novel cyclotides originated from chimeric precursors consisting of albumin-1 chain a and cyclotide domains in the Fabaceae family.

    PubMed

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

    2011-07-01

    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.

  7. Morpho-anatomical and growth alterations induced by arsenic in Cajanus cajan (L.) DC (Fabaceae).

    PubMed

    Pita-Barbosa, Alice; Gonçalves, Elton Carvalho; Azevedo, Aristéa Alves

    2015-08-01

    Arsenic (As) is a toxic element to most organisms. Studies investigating anatomic alterations due to As exposure in plants are scarce but of utmost importance to the establishment of environmental biomonitoring techniques. So, this study aimed to investigate the effects of As on the development and initial root growth in Cajanus cajan (Fabaceae), characterize and quantify the possible damages, evaluate genotoxic effects, and identify structural markers to be used in environmental bioindication. Plants were exposed hydroponically to 0.5, 1.0, 1.5, and 2.0 mg As L(-1), as sodium arsenate. Growth parameters were measured, and in the end of the exposure, root samples were analyzed for qualitative and quantitative anatomical alterations. Arsenic genotoxicity was evaluated through analysis of the mitotic index in the root apex. Compared to the control, As-treated seedlings showed an altered architecture, with significantly decreased root length (due to the lower mitotic index in the apical meristem and reduced elongation of parenchyma cells) with darkened color, and abnormal development of the root cap. A significant increase in vascular cylinder/root diameter ratio was also detected, due to the reduction of the cellular spaces in the cortex. The secondary xylem vessel elements were reduced in diameter and had sinuous walls. The severest damage was visible in the ramification zone, where uncommon division planes of phellogen and cambium cells and disintegration of the parenchyma cells adjacent to lateral roots were observed. The high sensibility of C. cajan to As was confirmed, since it caused severe damages in root growth and anatomy. The main structural markers for As toxicity were the altered root architecture, with the reduction of the elongation zone and increase of ramification zone length, and the root primordia retained within the cortex. Our results show a new approach about As toxicity and indicate that C. cajan is a promising species to be used for

  8. Morpho-anatomical and growth alterations induced by arsenic in Cajanus cajan (L.) DC (Fabaceae).

    PubMed

    Pita-Barbosa, Alice; Gonçalves, Elton Carvalho; Azevedo, Aristéa Alves

    2015-08-01

    Arsenic (As) is a toxic element to most organisms. Studies investigating anatomic alterations due to As exposure in plants are scarce but of utmost importance to the establishment of environmental biomonitoring techniques. So, this study aimed to investigate the effects of As on the development and initial root growth in Cajanus cajan (Fabaceae), characterize and quantify the possible damages, evaluate genotoxic effects, and identify structural markers to be used in environmental bioindication. Plants were exposed hydroponically to 0.5, 1.0, 1.5, and 2.0 mg As L(-1), as sodium arsenate. Growth parameters were measured, and in the end of the exposure, root samples were analyzed for qualitative and quantitative anatomical alterations. Arsenic genotoxicity was evaluated through analysis of the mitotic index in the root apex. Compared to the control, As-treated seedlings showed an altered architecture, with significantly decreased root length (due to the lower mitotic index in the apical meristem and reduced elongation of parenchyma cells) with darkened color, and abnormal development of the root cap. A significant increase in vascular cylinder/root diameter ratio was also detected, due to the reduction of the cellular spaces in the cortex. The secondary xylem vessel elements were reduced in diameter and had sinuous walls. The severest damage was visible in the ramification zone, where uncommon division planes of phellogen and cambium cells and disintegration of the parenchyma cells adjacent to lateral roots were observed. The high sensibility of C. cajan to As was confirmed, since it caused severe damages in root growth and anatomy. The main structural markers for As toxicity were the altered root architecture, with the reduction of the elongation zone and increase of ramification zone length, and the root primordia retained within the cortex. Our results show a new approach about As toxicity and indicate that C. cajan is a promising species to be used for

  9. The First Attested Extraction of Ancient DNA in Legumes (Fabaceae).

    PubMed

    Mikić, Aleksandar M

    2015-01-01

    Ancient DNA (aDNA) is any DNA extracted from ancient specimens, important for diverse evolutionary researches. The major obstacles in aDNA studies are mutations, contamination and fragmentation. Its studies may be crucial for crop history if integrated with human aDNA research and historical linguistics, both general and relating to agriculture. Legumes (Fabaceae) are one of the richest end economically most important plant families, not only from Neolithic onwards, since they were used as food by Neanderthals and Paleolithic modern man. The idea of extracting and analyzing legume aDNA was considered beneficial for both basic science and applied research, with an emphasis on genetic resources and plant breeding. The first reported successful and attested extraction of the legume aDNA was done from the sample of charred seeds of pea (Pisum sativum) and bitter vetch (Vicia ervilia) from Hissar, southeast Serbia, dated to 1,350-1,000 Before Christ. A modified version of cetyltrimethylammonium bromide (CTAB) method and the commercial kit for DNA extraction QIAGEN DNAesy yielded several ng μl(-1) of aDNA of both species and, after the whole genome amplification and with a fragment of nuclear ribosomal DNA gene 26S rDNA, resulted in the detection of the aDNA among the PCR products. A comparative analysis of four informative chloroplast DNA regions (trnSG, trnK, matK, and rbcL) among the modern wild and cultivated pea taxa demonstrated not only that the extracted aDNA was genuine, on the basis of mutation rate, but also that the ancient Hissar pea was most likely an early domesticated crop, related to the modern wild pea of a neighboring region. It is anticipated that this premier extraction of legume aDNA may provide taxonomists with the answers to diverse questions, such as leaf development in legumes, as well as with novel data on the single steps in domesticating legume crops worldwide. PMID:26635833

  10. The First Attested Extraction of Ancient DNA in Legumes (Fabaceae)

    PubMed Central

    Mikić, Aleksandar M.

    2015-01-01

    Ancient DNA (aDNA) is any DNA extracted from ancient specimens, important for diverse evolutionary researches. The major obstacles in aDNA studies are mutations, contamination and fragmentation. Its studies may be crucial for crop history if integrated with human aDNA research and historical linguistics, both general and relating to agriculture. Legumes (Fabaceae) are one of the richest end economically most important plant families, not only from Neolithic onwards, since they were used as food by Neanderthals and Paleolithic modern man. The idea of extracting and analyzing legume aDNA was considered beneficial for both basic science and applied research, with an emphasis on genetic resources and plant breeding. The first reported successful and attested extraction of the legume aDNA was done from the sample of charred seeds of pea (Pisum sativum) and bitter vetch (Vicia ervilia) from Hissar, southeast Serbia, dated to 1,350–1,000 Before Christ. A modified version of cetyltrimethylammonium bromide (CTAB) method and the commercial kit for DNA extraction QIAGEN DNAesy yielded several ng μl-1 of aDNA of both species and, after the whole genome amplification and with a fragment of nuclear ribosomal DNA gene 26S rDNA, resulted in the detection of the aDNA among the PCR products. A comparative analysis of four informative chloroplast DNA regions (trnSG, trnK, matK, and rbcL) among the modern wild and cultivated pea taxa demonstrated not only that the extracted aDNA was genuine, on the basis of mutation rate, but also that the ancient Hissar pea was most likely an early domesticated crop, related to the modern wild pea of a neighboring region. It is anticipated that this premier extraction of legume aDNA may provide taxonomists with the answers to diverse questions, such as leaf development in legumes, as well as with novel data on the single steps in domesticating legume crops worldwide. PMID:26635833

  11. Bioacoustics of Acanthoscelides obtectus (Say) (Coleoptera: Chrysomelidae: Bruchinae) on common beans Phaseolus vulgaris L. (Fabaceae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  13. 7 CFR 201.56-6 - Legume or pea family, Fabaceae (Leguminosae).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Legume or pea family, Fabaceae (Leguminosae). 201.56-6 Section 201.56-6 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE...

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

    PubMed Central

    Paiva, Elder Antônio Sousa

    2009-01-01

    Background and Aims 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. Methods 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. Key Results 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. Conclusions 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

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

    PubMed

    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.

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

    PubMed

    Luzia Delgado, Carolina Maria; Souza de Paula, Alexandre; Santos, Marisa; Silveira Paulilo, Maria Terezinha

    2015-03-01

    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 nonreated 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 15 degrees C 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 coats of the

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

    PubMed

    Luzia Delgado, Carolina Maria; Souza de Paula, Alexandre; Santos, Marisa; Silveira Paulilo, Maria Terezinha

    2015-03-01

    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 nonreated 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 15 degrees C 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 coats of the

  18. Pollen dispersal of tropical trees (Dinizia excelsa: Fabaceae) by native insects and African honeybees in pristine and fragmented Amazonian rainforest.

    PubMed

    Dick, Christopher W; Etchelecu, Gabriela; Austerlitz, Frédéric

    2003-03-01

    Tropical rainforest trees typically occur in low population densities and rely on animals for cross-pollination. It is of conservation interest therefore to understand how rainforest fragmentation may alter the pollination and breeding structure of remnant trees. Previous studies of the Amazonian tree Dinizia excelsa (Fabaceae) found African honeybees (Apis mellifera scutellata) as the predominant pollinators of trees in highly disturbed habitats, transporting pollen up to 3.2 km between pasture trees. Here, using microsatellite genotypes of seed arrays, we compare outcrossing rates and pollen dispersal distances of (i) remnant D. excelsa in three large ranches, and (ii) a population in undisturbed forest in which African honeybees were absent. Self-fertilization was more frequent in the disturbed habitats (14%, n = 277 seeds from 12 mothers) than in undisturbed forest (10%, n = 295 seeds from 13 mothers). Pollen dispersal was extensive in all three ranches compared to undisturbed forest, however. Using a twogener analysis, we estimated a mean pollen dispersal distance of 1509 m in Colosso ranch, assuming an exponential dispersal function, and 212 m in undisturbed forest. The low effective density of D. excelsa in undisturbed forest (approximately 0.1 trees/ha) indicates that large areas of rainforest must be preserved to maintain minimum viable populations. Our results also suggest, however, that in highly disturbed habitats Apis mellifera may expand genetic neighbourhood areas, thereby linking fragmented and continuous forest populations.

  19. Development of microsatellite loci of pod mahogany, Afzelia quanzensis (Fabaceae), by Illumina shotgun sequencing, and cross-amplification in A. africana1

    PubMed Central

    Jinga, Percy; Palagi, Jason; Ashley, Mary V.

    2016-01-01

    Premise of the study: Microsatellite loci were developed for Afzelia quanzensis (Fabaceae) as a first step toward investigating genetic diversity and population structure of the species in its native range. Methods and Results: Illumina shotgun sequencing was used to generate raw sequence reads, which were searched for potential microsatellite loci. A total of 70 potential microsatellite loci were tested for amplification and polymorphism, and 39 successfully amplified. Of the 39 loci that amplified, 12 were polymorphic while 27 were monomorphic. The 12 polymorphic loci were cross-amplified in A. africana, and eight successfully amplified. Conclusions: The 12 polymorphic microsatellite loci can be used for genetic studies of A. quanzensis, which can help determine its conservation status. Eight loci can also be used for genotyping in A. africana. PMID:27347453

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

    PubMed

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

    2016-07-01

    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. PMID:27302610

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

    PubMed

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

    2016-07-01

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

    PubMed

    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.

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

    PubMed Central

    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

  4. Nutritional characteristics of seed proteins in 28 Vicia species (Fabaceae) from Southern Spain.

    PubMed

    Pastor-Cavada, Elena; Juan, Rocio; Pastor, Julio E; Alaiz, Manuel; Vioque, Javier

    2011-10-01

    The study of local plants could provide useful data for the possible development of future crops with good nutritional and functional properties. The nutritional characteristics of the seed proteins of 28 Vicia species (31 taxa) (Fabaceae) from Spain were studied. Protein contents in studied Vicia ranged from 20.1% in V. articulata to 32% in V. pyrenaica. V. altissima, which is only deficient in Trp, showed the most balanced amino acid composition, while the remaining taxa were limiting in Met, Cys, and Trp. In vitro protein digestibility (IVPD) ranged from 78% in V. incana to 86.3% in V. hirsuta. In addition to the amino acid composition and IVPD, other nutritional parameters, such as amino acid score, biological value, protein efficiency ratio, or protein digestibility corrected amino acid score, were studied. Results confirm the interest of studying wild populations of cultivated and non cultivated Vicia species as potentially interesting sources of seeds with good nutritional characteristics.

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

    PubMed

    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. PMID:25971549

  6. DNA microsatellite markers for Swartzia glazioviana (Fabaceae), a threatened species from the Brazilian Atlantic Forest1

    PubMed Central

    Spoladore, Janaína; Mansano, Vidal F.; Dias de Freitas, Luan C.; Sebbenn, Alexandre M.; Lemes, Maristerra R.

    2016-01-01

    Premise of the study: Development and characterization of a set of DNA microsatellite markers for Swartzia glazioviana (Fabaceae), a naturally rare and threatened tree species, were carried out to investigate its conservation genetics. Methods and Results: Through an enriched genomic library procedure, 10 DNA microsatellite loci were isolated and characterized for the species. The mean expected heterozygosity was 0.776 (0.424–0.894). Cross-species amplifications of these loci were successfully tested for six congener taxa (S. apetala var. apetala, S. flaemingii, S. langsdorffii, S. macrostachya, S. myrtifolia var. elegans, and S. simplex var. continentalis). Conclusions: The 10 polymorphic microsatellite markers developed are quite informative and will provide a valuable resource to study the population and conservation genetics of S. glazioviana and other Swartzia species. PMID:26949573

  7. Isolation and characterization of 28 microsatellite loci for a Korean endemic, Lespedeza maritima (Fabaceae)1

    PubMed Central

    Jin, Dong-Pil; Cho, Won-Bum; Choi, In-Su; Choi, Byoung-Hee

    2016-01-01

    Premise of the study: We developed microsatellite primers for Lespedeza maritima (Fabaceae), a Korean endemic shrub, and conducted cross-amplifications for closely related species. Methods and Results: We produced 28 polymorphic microsatellite markers through reference mapping of 300-bp paired-end reads obtained from Illumina MiSeq data. For 47 individual plants from two populations, the total alleles numbered two to 13, and observed and expected heterozygosities ranged from 0.067 to 0.867 and from 0.064 to 0.848, respectively. Most of these markers were well amplified in closely related species. Conclusions: In future research, the microsatellite markers described here will help reveal the taxonomic entity of this species. PMID:26819860

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

    PubMed

    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.

  9. Medicinal Plants Used in Wound Care: A Study of Prosopis africana (Fabaceae) Stem Bark

    PubMed Central

    Ezike, A. C.; Akah, P. A.; Okoli, C. O.; Udegbunam, S.; Okwume, N.; Okeke, C.; Iloani, O.

    2010-01-01

    The effects of the methanol extract of the stem bark of Prosopis africana (Guill., Perrott. and Rich.) Taubert (Fabaceae) on bleeding/clotting and coagulation time, excision and dead space wounds were studied in rats. Also, the extract was subjected to antibacterial, and acute toxicity and lethality (LD50) tests. The extract significantly (P<0.05) reduced bleeding/clotting and coagulation time in rats. It also reduced epithelialization period of excision wounds in rats and inhibited the growth of laboratory strains of Staphylococcus aureus, Bacillus subtilis, Salmonella typhi, Pseudomonas aeruginosa and Klebsiella pneumoniae to varying extents. Acute toxicity and lethality (LD50) test on the extract established an LD50 of 774 mg/kg (i.p) in mice while phytochemical analysis gave positive reactions for alkaloids, saponins, tannins, flavonoids, steroids, terpenoids and carbohydrates. The results of this study demonstrate the beneficial effects of the stem bark of P. africana in wound care. PMID:21188042

  10. Development and characterization of microsatellite markers for Piptadenia gonoacantha (Fabaceae)1

    PubMed Central

    Grando, Carolina; Bajay, Miklos M.; Bajay, Stephanie K.; Schwarcz, Kaiser D.; Campos, Jaqueline B.; Brancalion, Pedro H. S.; Pinheiro, José B.; Rodrigues, Ricardo R.; Souza, Anete P.; Zucchi, Maria I.

    2015-01-01

    • Premise of the study: Microsatellite primers were designed for Piptadenia gonoacantha (Fabaceae) and characterized to estimate genetic diversity parameters. The species is a native tree from the Atlantic Forest biome commonly used in forest restoration; it has medicinal potential and the wood is economically useful. • Methods and Results: Twenty-eight microsatellite loci were identified from an enriched genomic library. Fifteen loci resulted in successful amplifications and were characterized in a natural population of 94 individuals. Twelve loci were polymorphic, with allele numbers ranging from three to 15 per locus, and expected and observed heterozygosities ranging from 0.2142 to 0.8325 and 0.190 to 0.769, respectively. • Conclusions: The developed markers will be used in further studies of population genetics of P. gonoacantha, aimed at conservation and management of the species in natural populations and in forest restoration projects. PMID:25699220

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

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

    PubMed Central

    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

  13. Tamarindus indica L. (Fabaceae): patterns of use in traditional African medicine.

    PubMed

    Havinga, Reinout M; Hartl, Anna; Putscher, Johanna; Prehsler, Sarah; Buchmann, Christine; Vogl, Christian R

    2010-02-17

    To increase the understanding of the ethnopharmacology of a single species, elaboration of dispersed primary data is required. Tamarindus indica L. (Fabaceae), or tamarind, is a common tree, especially in West Africa, with a good potential to contribute to affordable local health care based on traditional medicine (TM). For this single species review, more than 60 references with detailed information on the ethnopharmacology of Tamarindus indica in the African context were selected. It showed that most prominently, the fruits are used as laxative or febrifuge throughout the Sahel and Soudan ecological zones. Tamarind bark and leaves are often involved in the treatment of wounds, especially in central West Africa. While the bark is used to treat diarrhoea in West Africa, the leaves are used for this purpose in East Africa. Our findings suggest a difference in the way tamarind is used between East and West Africa and we assess the similarities of its uses within those regions. This review demonstrates the capability of literature research to reveal knowledge by mining and compiling information from the growing body of primary ethnopharmacologic data, much of which is published in this journal. By creating a specific profile of tamarind in the context of traditional medicine throughout Africa, the authors contribute to the collection of current ethnobotanic species accounts on Tamarindus indica that tend to be qualitative and more general.

  14. Chemical analysis and nutritional assessment of Teramnus labialis (L.) Spreng. (Fabaceae).

    PubMed

    Viswanathan, M B; Thangadurai, D; Vendan, K T; Ramesh, N

    1999-01-01

    Seeds of Teramnus labialis (L.) Spreng. (Fabaceae), used as food by Malayali tribals in the Kollihills of Salem District, Tamil Nadu in South India, were investigated for their nutritional value. These seeds were analyzed for proximate composition, total (true) seed proteins, seed protein fractions, amino acid composition, fatty acid composition, minerals and antinutritional factors. Crude protein, crude fat, ash, and nitrogen free extracts constituted 22.86%, 6.10%, 4.62%, and, 58.15%, respectively, of the seed weight. The caloric value of 100 g dry matter of seed material was 378.94 kcal. The essential amino acids lysine, leucine + isoleucine, arginine, valine and histidine were present in relatively large quantities. The unsaturated fatty acids constituted more than 60% of the crude fat. Concentrations of minerals such as potassium, magnesium, calcium, and, phosphorus were high. Antinutritional factors such as total free phenols, tannins, L-DOPA, hydrogen cyanide and phytic acid were present in minute quantities. These antinutritional factors are potentially eliminated using the conventional method of soaking the seeds in water, boiling with water and decanting prior to consumption.

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

    PubMed

    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

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

    PubMed Central

    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

  17. Exploration of diuretic potential and electrolyte excretion of Tephrosia purpurea (Fabaceae) in rats.

    PubMed

    Ashokkumar, D; Narayana, T V; Vidyasagar; Mazumder, Upal Kanti; Gupta, Malaya

    2012-03-01

    Tephrosia purpurea (Fabaceae) is a well-known traditional plant with diuretic effect but no scientific work published till date to support the claimed ethnomedical use. Therefore, the present study appraised the diuretic potential of methanol extract of Tephrosia purpurea (METP) in male wistar rats. The powdered plant material was extracted with methanol by hot extraction. The animals were divided into five groups for diuretic activity. The first group served as saline control (0.9%% saline solution, 25 ml/kg, body weight (b.w)), the second group received osmotic diuretic, urea (1 g/kg b.w), the third group received high-ceiling diuretic, furosemide (5 mg/kg b.w), and the other two groups were administered various concentrations of METP (200 mg/kg and 400 mg/kg b.w) orally to hydrated rats and their urine volume was measured at 5th and 24th hr after drug administration, while animals were deprived of food and water. After collection of urine, the parameters such as urine output, diuretic activity, electrolyte excretion of Na(++), K(++), Ca(2++), and Cl(-), and pH were analyzed. METP at various dose levels exhibited significant diuretic activity as evidenced by increased urine volume, electrolyte concentration, and alkaline pH in comparison to control group of animals. The present study provides a quantitative basis for explaining the folkloric use of Tephrosia purpurea as a diuretic agent in Indian traditional system of medicine. PMID:22432799

  18. Activity of isoflavans of Dalea aurea (Fabaceae) against the opportunistic ameba naegleria fowleri.

    PubMed

    Belofsky, Gil; Carreno, Roberto; Goswick, Shannon M; John, David T

    2006-03-01

    One new and one known isoflavan, 3 S(+)-7-methoxymanuifolin K (1) and manuifolin K (2), respectively, were isolated from methanolic extracts of Dalea aurea (Fabaceae). Isoflavans 1 and 2 exhibited significant in vitro activity against the ameba Naegleria fowleri, an organism responsible for an infrequent but rapidly fatal form of primary amebic meningoencephalitis (PAM). At concentrations of 30 microM, both 1 and 2 caused growth inhibition of N. fowleri at a level comparable to amphotericin B (at 0.1 microM), the currently preferred treatment for this disease. Over a seven-day growth period, 1 and 2 (30 microM) exhibited superior growth inhibition of N. fowleri than amphotericin B after day 4. Isoflavan 2 was evaluated in a mouse model of PAM at a dose of 25 mg/kg/day for five days. While amphotericin B (2.5 mg/kg/day) offered 12.5 % protection of the mice, compound 2 did not protect the mice from PAM infection compared to controls.

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

    PubMed

    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.

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

    PubMed

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

    2014-11-11

    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.

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

    PubMed

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

    2014-11-11

    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. PMID:25387391

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

    PubMed

    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. PMID:25590708

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

    PubMed

    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. PMID:18761068

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

    PubMed

    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.

  5. Ovularia puerariae Sawada is the hyphomycetous anamorph of a new Marasmius species on living leaves of kudzu (Pueraria montana, Fabaceae).

    PubMed

    Kirschner, Roland; Lee, I-Shu; Chen, Chee-Jen

    2013-01-01

    An arthroconidial hyphomycete on living leaves of kudzu (Pueraria montana, Fabaceae), originally described by Sawada in 1959 as Ovularia puerariae, was rediscovered. This anamorph is connected to an unknown Marasmius teleomorph belonging to section Globulares, which develops on the same living leaves. Ultrastructure and LSU rDNA sequence analysis of the anamorph confirm this connection. The fungus does not have only a unique biology among agarics, comparable only to Mycena citricolor, but also has the potential for application as a control agent of kudzu. During comparison with similar anamorph genera, Illosporium graminicola was found to be a synonym for Beniowskia sphaeroidea. PMID:23360973

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

    PubMed

    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.

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

    PubMed

    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.

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

    PubMed

    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

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed

    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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

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

    PubMed

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

    2015-01-01

    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. PMID:26250291

  13. In vitro micropropagation of Desmodium gangeticum (L.) DC (Fam-Fabaceae): a medicinal legume through axillary bud multiplication.

    PubMed

    Puhan, Puspashree; Rath, Shiba Prasad

    2012-05-15

    Medicinal plants possess unlimited and untapped wealth of chemical compounds with high drug potential which make these plants useful as sources of biomedicines. The rising demand for herbal medicines in the organized manufacturing sector has ruthlessly exploited the wild growing plant population those have bulk use. So for high rate multiplication of different medicinal plants, it is necessary to standardize the protocol for high regeneration. The efficiency of any regeneration is primarily depends on factors like type of explants used, composition of the medium and type of genotype. Here, we have developed a regeneration protocol of Desmodium gangeticum (L.) DC (Salparni, Fam- Fabaceae) a medicinal plant through axillary bud multiplication. Nodal explants from Desmodium gangeticum plants were cultured on Murashige and Skoog's basal medium with Kn or BA at different concentrations. 0.5 mg L(-1) BA in the medium, showed shoot multiplication. Regenerated shoots measuring 3 cm or more were excised and planted on semi solid basal medium supplemented with varying concentrations of either IAA or IBA for induction of rooting. IBA treatment at 1.0 mg L(-1) was the best eliciting 100% rooting response. The in vitro propagation protocol standardized can be highly useful in raising quality planting materials of Desmodium gangeticum for commercial plantation programmes and germplasm conservation.

  14. Antioxidative and antibacterial effects of seeds and fruit rind of nutraceutical plants belonging to the Fabaceae family.

    PubMed

    Chanda, Sumitra; Dudhatra, Sandeep; Kaneria, Mital

    2010-12-01

    In the present study, the seeds and fruit rind of six plants of the Fabaceae family were selected to evaluate their potential as antioxidant and antibacterial agents. The dried powders were individually extracted with various organic solvents by the cold percolation method, were evaluated for antibacterial activity and methanol extracts used for antioxidant activities. Total phenol, protein and sugar contents were also measured. Antioxidant activities were measured by DPPH free radical scavenging activity, superoxide anion radical scavenging activity and reducing capacity assessment. Antibacterial activity was measured by the agar well diffusion method against four Gram positive and four Gram negative bacteria. The methanol extract of the fruit rind of C. indica showed the maximum DPPH free radical scavenging activity, superoxide anion radical scavenging activity, a high reducing capacity assessment and also had the highest total phenol content. There was a direct correlation between the phenol content and the antioxidant activity. The antibacterial activity of all the extracts was more pronounced on Gram positive bacteria than on Gram negative bacteria. Thus, the fruit rind of C. indica showed the best antioxidant and antibacterial activities.

  15. Characterization of nine microsatellite loci for the tree species Parapiptadenia rigida (Fabaceae-Mimosoideae) and their transferability.

    PubMed

    Costa, B F; Rodrigues, L A; Ruas, E A; Souza, L B; Ruas, C F; Vieira, B G; Conson, A R O; Ruas, P M

    2012-01-01

    Parapiptadenia rigida, locally known as angico, is a tropical tree common in the semideciduous Brazilian forest. Its wood is naturally resistant to insect attack and is useful for construction. Extracts from the tree have medicinal properties. We characterized nine microsatellite loci for P. rigida. Thirty-five alleles were detected in a sample of 45 individuals from 3 different populations, with an average of 3.9 alleles per locus. The average polymorphic information content ranged from 0.099 to 0.640. Observed and expected heterozygosities varied from 0.111 to 0.489 and from 0.106 to 0.707, respectively. One locus exhibited significant deviation from Hardy-Weinberg equilibrium and four pairs of loci showed significant linkage disequilibrium. All nine primers were tested for cross-amplification in species from the Fabaceae-Mimosoidea family, yielding a transferability success rate of 7 loci in Stryphnodendron adstringens to 0 transferred loci in Pithecellobium incuriale and Inga marginata. These microsatellites will be valuable to study population genetics of this and other species where primer transferability was detected.

  16. How a phosphorus-acquisition strategy based on carboxylate exudation powers the success and agronomic potential of lupines (Lupinus, Fabaceae).

    PubMed

    Lambers, Hans; Clements, Jon C; Nelson, Matthew N

    2013-02-01

    Lupines (Lupinus species; Fabaceae) are an ancient crop with great potential to be developed further for high-protein feed and food, cover crops, and phytoremediation. Being legumes, they are capable of symbiotically fixing atmospheric nitrogen. However, Lupinus species appear to be nonmycorrhizal or weakly mycorrhizal at most; instead some produce cluster roots, which release vast amounts of phosphate-mobilizing carboxylates (inorganic anions). Other lupines produce cluster-like roots, which function in a similar manner, and some release large amounts of carboxylates without specialized roots. These traits associated with nutrient acquisition make lupines ideally suited for either impoverished soils or soils with large amounts of phosphorus that is poorly available for most plants, e.g., acidic or alkaline soils. Here we explore how common the nonmycorrhizal phosphorus-acquisition strategy based on exudation of carboxylates is in the genus Lupinus, concluding it is very likely more widespread than generally acknowledged. This trait may partly account for the role of lupines as pioneers or invasive species, but also makes them suitable crop plants while we reach "peak phosphorus".

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

    PubMed

    Hardion, Laurent; Dumas, Pierre-Jean; Abdel-Samad, Farah; Kharrat, Magda Bou Dagher; 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. PMID:26804816

  18. 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.

    PubMed

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

    2016-01-01

    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 < 0.05), as well as higher total polyphenol and flavonoid contents than other plant extracts. Minimum inhibitory concentrations on MRSA isolates ranged from 388.4 ± 0.2 mg/L, in D. sanguinalis, to 5.5 ± 0.1 mg/L, in L. aphaca. The methanolic extracts of L. aphaca (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. PMID:27585260

  19. 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.

    PubMed

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

    2016-01-01

    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 < 0.05), as well as higher total polyphenol and flavonoid contents than other plant extracts. Minimum inhibitory concentrations on MRSA isolates ranged from 388.4 ± 0.2 mg/L, in D. sanguinalis, to 5.5 ± 0.1 mg/L, in L. aphaca. The methanolic extracts of L. aphaca (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.

  20. Wood growth patterns of Macrolobium acaciifolium (Benth.) Benth. (Fabaceae) in Amazonian black-water and white-water floodplain forests.

    PubMed

    Schöngart, Jochen; Piedade, Maria Teresa F; Wittmann, Florian; Junk, Wolfgang J; Worbes, Martin

    2005-09-01

    Macrolobium acaciifolium (Benth.) Benth. (Fabaceae) is a dominant legume tree species occurring at low elevations of nutrient-poor black-water (igapó) and nutrient-rich white-water floodplain forests (várzea) of Amazonia. As a consequence of the annual long-term flooding this species forms distinct annual tree rings allowing dendrochronological analyses. From both floodplain types in Central Amazonia we sampled cores from 20 large canopy trees growing at identical elevations with a flood-height up to 7 m. We determined tree age, wood density (WD) and mean radial increment (MRI) and synchronized ring-width patterns of single trees to construct tree-ring chronologies for every study site. Maximum tree age found in the igapó was more than 500 years, contrary to the várzea with ages not older than 200 years. MRI and WD were significantly lower in the igapó (MRI=1.52+/-0.38 mm year(-1), WD=0.39+/-0.05 g cm(-3)) than in the várzea (MRI=2.66+/-0.67 mm year(-1), WD=0.45+/-0.03 g cm(-3)). In both floodplain forests we developed tree-ring chronologies comprising the period 1857-2003 (n=7 trees) in the várzea and 1606-2003 (n=13 trees) in the igapó. The ring-width in both floodplain forests was significantly correlated with the length of the terrestrial phase (vegetation period) derived from the daily recorded water level in the port of Manaus since 1903. In both chronologies we found increased wood growth during El Niño events causing negative precipitation anomalies and a lower water discharge in Amazonian rivers, which leads to an extension of the terrestrial phase. The climate signal of La Niña was not evident in the dendroclimatic proxies.

  1. Phylogeography of East Asian Lespedeza buergeri (Fabaceae) based on chloroplast and nuclear ribosomal DNA sequence variations.

    PubMed

    Jin, Dong-Pil; Lee, Jung-Hyun; Xu, Bo; Choi, Byoung-Hee

    2016-09-01

    The dynamic changes in land configuration during the Quaternary that were accompanied by climatic oscillations have significantly influenced the current distribution and genetic structure of warm-temperate forests in East Asia. Although recent surveys have been conducted, the historical migration of forest species via land bridges and, especially, the origins of Korean populations remains conjectural. Here, we reveal the genetic structure of Lespedeza buergeri, a warm-temperate shrub that is disjunctively distributed around the East China Sea (ECS) at China, Korea, and Japan. Two non-coding regions (rpl32-trnL, psbA-trnH) of chloroplast DNA (cpDNA) and the internal transcribed spacer of nuclear ribosomal DNA (nrITS) were analyzed for 188 individuals from 16 populations, which covered almost all of its distribution. The nrITS data demonstrated a genetic structure that followed geographic boundaries. This examination utilized AMOVA, comparisons of genetic differentiation based on haplotype frequency/genetic mutations among haplotypes, and Mantel tests. However, the cpDNA data showed contrasting genetic pattern, implying that this difference was due to a slower mutation rate in cpDNA than in nrITS. These results indicated frequent migration by this species via an ECS land bridge during the early Pleistocene that then tapered gradually toward the late Pleistocene. A genetic isolation between western and eastern Japan coincided with broad consensus that was suggested by the presence of other warm-temperate plants in that country. For Korean populations, high genetic diversity indicated the existence of refugia during the Last Glacial Maximum on the Korean Peninsula. However, their closeness with western Japanese populations at the level of haplotype clade implied that gene flow from western Japanese refugia was possible until post-glacial processing occurred through the Korea/Tsushima Strait land bridge. PMID:27206725

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

    PubMed

    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

  3. Development of microsatellite markers in Cratylia mollis and their transferability to C. argentea (Fabaceae)1

    PubMed Central

    López-Roberts, M. Cristina; de Queiroz, Luciano Paganucci; van den Berg, Cássio

    2013-01-01

    • Premise of the study: This work aimed to develop microsatellite markers for Cratylia mollis as tools to assess its genetic diversity and structure and to evaluate their potential cross-amplification in related species. • Methods and Results: Microsatellite markers were developed using a microsatellite-enriched library and an intersimple sequence repeat library. From a set of 19 markers, 12 microsatellite loci were polymorphic and presented considerable variation in allele number (2–11), expected heterozygosity (0.226–0.883), and polymorphism information content per locus (0.212–0.870). Cross-amplification in C. argentea was successful in 16 loci, 12 of which were polymorphic (2–10 alleles). • Conclusions: The polymorphism of this set of microsatellite markers for C. mollis, as well as their successful cross-amplification in C. intermedia and C. bahiensis and their transferability to C. argentea, supports their use in future comparative studies to understand the mechanism involved in population divergence and speciation in the genus. PMID:25202484

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

    PubMed

    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

  5. Antioxidant responses of Annelids, Brassicaceae and Fabaceae to pollutants: a review.

    PubMed

    Bernard, F; Brulle, F; Dumez, S; Lemiere, S; Platel, A; Nesslany, F; Cuny, D; Deram, A; Vandenbulcke, F

    2015-04-01

    Pollutants, such as Metal Trace Elements (MTEs) and organic compounds (polycyclic aromatic hydrocarbons, pesticides), can impact DNA structure of living organisms and thus generate damage. For instance, cadmium is a well-known genotoxic and mechanisms explaining its clastogenicity are mainly indirect: inhibition of DNA repair mechanisms and/or induction of Reactive Oxygen Species (ROS). Animal or vegetal cells use antioxidant defense systems to protect themselves against ROS produced during oxidative stress. Because tolerance of organisms depends, at least partially, on their ability to cope with ROS, the mechanisms of production and management of ROS were investigated a lot in Ecotoxicology as markers of biotic and abiotic stress. This was mainly done through the measurement of enzyme activities The present Review focuses on 3 test species living in close contact with soil that are often used in soil ecotoxicology: the worm Eisenia fetida, and two plant species, Trifolium repens (white clover) and Brassica oleracea (cabbage). E. fetida is a soil-dwelling organism commonly used for biomonitoring. T. repens is a symbiotic plant species which forms root nodule with soil bacteria, while B. oleracea is a non-symbiotic plant. In literature, some oxidative stress enzyme activities have already been measured in those species but such analyses do not allow distinction between individual enzyme involvements in oxidative stress. Gene expression studies would allow this distinction at the transcriptomic level. A literature review and a data search in molecular database were carried out on the basis of keywords in Scopus, in PubMed and in Genbank™ for each species. Molecular data regarding E. fetida were already available in databases, but a lack of data regarding oxidative stress related genes was observed for T. repens and B. oleracea. By exploiting the conservation observed between species and using molecular biology techniques, we partially cloned missing candidates

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

    PubMed

    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].

  7. Influence of the drying method in the antioxidant potential and chemical composition of four shrubby flowering plants from the tribe Genisteae (Fabaceae).

    PubMed

    Pinela, José; Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C F R

    2011-11-01

    Flowers from several common Mediterranean shrubs, such as those from the Cytisus genus and Genista genus (tribe Genisteae/Fabaceae) have long been used for medicinal purposes and seasoning in the northeastern Portuguese region. Despite, the shade-drying traditionally used to process these plants, freeze-drying is claimed to better preserve the quality of medicinal plants. Herein, the effects of drying process in the antioxidants composition and properties of Cytisus multiflorus, Cytisus scoparius, Cytisus striatus and Pterospartum tridentatum were evaluated. Freeze-dried P. tridentatum revealed the highest antioxidant properties (EC(50) values ≤ 0.15 mg/ml). Freeze-drying benefits were confirmed showing, the samples submitted to this process, higher antioxidant activity and higher concentrations of hydrophilic (phenolics, ascorbic acid and sugars) and lipophilic (tocopherols, chlorophylls and lycopene) compounds. This process could be applied in scale-up treatments of the studied plants for cosmetic or pharmaceutical applications.

  8. 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)

    PubMed Central

    2013-01-01

    Background 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. Results 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

  9. Derivation and validation of a binomial sequential decision plan for managing pea aphids (Hemiptera: Aphididae) as direct pests of dry pea (Fabales: Fabaceae) in the Pacific Northwest.

    PubMed

    Stokes, Bradley S; Bechinski, Edward J; Eigenbrode, Sanford D

    2013-12-01

    We developed a binomial sequential decision plan that classifies the economic status of nonviruliferous pea aphids, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), in commercial dry peas, Pisum sativum L. (Fabales: Fabaceae), in the Palouse region of northern Idaho and eastern Washington state. Relationships between mean pea aphid density per plant (x) and the proportion of aphid-infested plants (Pi) were determined by in situ visual counts of 100 plants on each of 27 seasonal dates during 2011 from early vegetative plant growth (stage V105) to late reproductive growth (stage R207) at two field sites near Moscow, ID. The best-fit Nachman model Pi = 1 - exp(-0.3616 x(0.808)) was used to restate the limits of noneconomic and economic infestations from one and three aphids per plant to 30 and 58% aphid-infested plants, respectively. Sequential decision plans were computed using the stop-line formulas of Waters for Wald's Sequential Probability Ratio Test. Validation of the sequential decision plan by simulated sampling from the 2011 data as well as from six commercial fields sampled during 2012 showed that when observed field densities either exceeded the economic injury level or were less than one third the economic injury level, the plan correctly classified aphid economic status in >99% of the resampling trials. Practical implementation of the plan is discussed.

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

    PubMed

    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]. PMID:26064022

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

    PubMed

    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.

  12. Response of Pisum sativum (Fabales: Fabaceae) to Sitona lineatus (Coleoptera: Curculionidae) infestation: effect of adult weevil density on damage, larval population, and yield loss.

    PubMed

    Vankosky, M A; Cárcamo, H A; Dosdall, L M

    2011-10-01

    Sitona lineatus L. (Coleoptera: Curculionidae) is an invasive pest in North America and its geographical range is currently expanding across the Canadian prairies. Adults and larvae of S. lineatus feed upon the foliage and root nodules, respectively, of field pea, Pisum sativum L. (Fabales: Fabaceae), and may contribute to economic losses when population densities are high. Integrated pest management (IPM) programs that incorporate economic thresholds should be used to manage S. lineatus populations in a sustainable manner. The impact of nitrogen fertilizer on field pea yield and the relationships between adult weevil density and above- and below-ground damage and yield were investigated in southern Alberta, Canada using exclusion cages on field pea plots. In each cage, 32 field pea plants were exposed to weevil densities ranging from zero to one adult weevil per plant. Nitrogen-fertilized plants yielded 16% more than unfertilized plants. Nitrogen-fertilized plants had fewer root nodules than unfertilized plants, but fertilizer had no effect on foliar feeding by S. lineatus. Adult density affected foliar feeding damage, with increases in above-ground damage associated with increases in S. lineatus density. Adult density did not affect root nodule damage, larval density, foliar biomass or seed weight. Overall, these results indicate that terminal leaf damage may be used to estimate adult weevil density but cannot be used to predict larval density or yield loss. Further research is required to better understand the impact of larval damage on yield and determine if economic thresholds can be developed using data from large-scale production systems.

  13. [Seedlings growth and survival of five Acacia (Fabaceae) species that coexists in neotropical semi-arid forests of Argentina, under different light and water availability conditions].

    PubMed

    Venier, Paula; Cabido, Marcelo; Mangeaud, Arnaldo; Funes, Guillermo

    2013-06-01

    Seedlings growth and survival of five Acacia (Fabaceae) species that coexists in neotropical semi-arid forests of Argentina, under different light and water availability conditions. Seedling establishment is one of the most risky stages of plants, especially in arid and semiarid regions, where low water availability and high solar radiation influence its emergence, development and survival. In seasonally dry xerophytic forests occurring in North-Western Córdoba, central Argentina, five neotropical species of Acacia co-exist: A. aroma, A. caven, A. atramentaria, A. gilliesii and A. praecox. With the aim to evaluate growth variables and survival of these five species seedlings, in response to water stress and different light availability conditions, a greenhouse experiment was undertaken from March to June of 2010. Although small differences were found between species (F = 5.66, p = 0.001), all of them showed high percentages of seedling survival in response to different light and water treatments, suggesting that seedlings would be tolerant to water stress and could be established both in light and shade. On the other hand, although all species showed an increase in growth in light conditions and without water stress, we have found some trends towards a greater growth in the seedlings ofA. aroma, A. caven and A. atramentaria when compared to those of A. praecox and A. gilliessi in most of the variables considered (F = 41.9, p < 0.0001; F = 7.06, p < 0.0001; F = 53.59, p < 0.0001). This pattern was confirmed through a cluster analysis that classified the species in two main groups. These results, together with others already reported, would indicate a regenerative niche differentiation that might be favoring the regional coexistence of these five species in semiarid forests in central Argentina.

  14. 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.

    PubMed

    Tala, Viviane Raïssa Sipowo; Candida da Silva, Viviane; Rodrigues, Clenilson Martins; Nkengfack, Augustin Ephrem; dos Santos, Lourdes Campaner; Vilegas, Wagner

    2013-03-01

    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.

  15. Concordance between Phylogeographical and Biogeographical Patterns in the Brazilian Cerrado: Diversification of the Endemic Tree Dalbergia miscolobium (Fabaceae)

    PubMed Central

    Novaes, Renan Milagres Lage; Ribeiro, Renata Acácio; Lemos-Filho, José Pires; Lovato, Maria Bernadete

    2013-01-01

    Few studies have addressed the phylogeography of species of the Cerrado, the largest savanna biome of South America. Here we aimed to investigate the phylogeographical structure of Dalbergia miscolobium, a widespread tree from the Cerrado, and to verify its concordance with plant phylogeographical and biogeographical patterns so far described. A total of 287 individuals from 32 populations were analyzed by sequencing the trnL intron of the chloroplast DNA and the internal transcribed spacer of the nuclear ribosomal DNA. Analysis of population structure and tests of population expansion were performed and the time of divergence of haplotypes was estimated. Twelve and 27 haplotypes were identified in the cpDNA and nrDNA data, respectively. The star-like network configuration and the mismatch distributions indicated a recent spatial and demographic expansion of the species. Consistent with previous tree phylogeographical studies of Cerrado trees, the cpDNA also suggested a recent expansion towards the southern Cerrado. The diversity of D. miscolobium was widespread but high levels of genetic diversity were found in the Central Eastern and in the southern portion of Central Western Cerrado. The combined analysis of cpDNA and nrDNA supported a phylogeographic structure into seven groups. The phylogeographical pattern showed many concordances with biogeographical and phylogeographical studies in the Cerrado, mainly with the Cerrado phytogeographic provinces superimposed to our sampling area. The data reinforced the uniqueness of Northeastern and Southeastern Cerrados and the differentiation between Eastern and Western Central Cerrados. The recent diversification of the species (estimated between the Pliocene and the Pleistocene) and the ‘genealogical concordances’ suggest that a shared and persistent pattern of species diversification might have been present in the Cerrado over time. This is the first time that an extensive ‘genealogical concordance’ between

  16. [Signaling Systems of Rhizobia (Rhizobiaceae) and Leguminous Plants (Fabaceae) upon the Formation of a Legume-Rhizobium Symbiosis (Review)].

    PubMed

    Glyan'ko, A K

    2015-01-01

    Data from the literature and our own data on the participation and interrelation of bacterial signaling Nod-factors and components of the calcium, NADPH-oxidase, and NO-synthase signaling systems of a plant at the preinfection and infectious stages of the formation of a legume-rhizobium symbiosis are summarized in this review. The physiological role of Nod-factors, reactive oxygen species (ROS), calcium (Ca2+), NADPH-oxidase, nitric oxide (NO), and their cross influence on the processes determining the formation of symbiotic structures on the roots of the host plant is discussed.

  17. Microsatellite primers for Parkia biglobosa (Fabaceae: Mimosoideae) reveal that a single plant sires all seeds per pod1

    PubMed Central

    Lassen, Kristin Marie; Kjær, Erik Dahl; Ouédraogo, Moussa; Nielsen, Lene Rostgaard

    2014-01-01

    • Premise of the study: Microsatellite primers were developed for an indigenous fruit tree, Parkia biglobosa, as a tool to study reproductive biology and population structure. Here we use the primers to determine the number of fathers per pod. • Methods and Results: Microsatellite loci were enriched in a genomic sample and isolated using pyrosequencing. Eleven primer pairs were characterized in two populations of P. biglobosa in Burkina Faso (each with 40 trees). The number of alleles per locus ranged from eight to 15, and one locus had null alleles. We genotyped seeds from 24 open-pollinated pods. The genotypic profiles of seeds per pod suggest that all seeds are outcrossed and that only one pollen donor sires all ovules in a single fruit. • Conclusions: Ten microsatellite markers were highly polymorphic. All seeds per pod of P. biglobosa were full siblings. The markers will be useful for reproductive and population genetic studies. PMID:25202634

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

    PubMed Central

    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

  19. Effect of isoflavone from Flemingia vestita (Fabaceae) on the Ca2+ homeostasis in Raillietina echinobothrida, the cestode of domestic fowl.

    PubMed

    Das, Bidyadhar; Tandon, Veena; Saha, Nirmalendu

    2006-03-01

    The alcoholic crude root-peel extract of Flemingia vestita and its major isoflavone, genistein, have been shown to have a vermifugal/vermicidal effect by causing a flaccid paralysis accompanied by alterations in the structural architecture of the tegumental interface and metabolic activity in Raillietina echinobothrida, the cestode of domestic fowl. In the present study, the crude root-peel extract and pure genistein were tested in vitro with respect to Ca2+ homeostasis and the occurrence of some metal ions was detected in the parasite. Live cestodes were incubated in pre-defined concentrations of the crude root-peel extract, genistein and praziquantel (as reference drug), till the paralysis time with simultaneous maintenance of respective controls. In the parasite tissue, a significant amount of Ca2+ (approximately 400 microg/g dry tissue wt) was found to be present besides magnesium, iron, zinc, lead and chromium, whilst manganese, cadmium and nickel were below the level of detection. The Ca2+ concentration was decreased significantly by 39%-49%, in the parasite tissue exposed to the test materials in comparison to the respective controls. There was also an increase in Ca2+ efflux by 91%-160% into the culture medium under similar treatments. The changes in Ca2+ homeostasis may be related to the rapid muscular contraction and consequent paralysis in the parasite due to the anthelmintic stress caused by the phytochemicals of F. vestita. PMID:16198617

  20. Effect of isoflavone from Flemingia vestita (Fabaceae) on the Ca2+ homeostasis in Raillietina echinobothrida, the cestode of domestic fowl.

    PubMed

    Das, Bidyadhar; Tandon, Veena; Saha, Nirmalendu

    2006-03-01

    The alcoholic crude root-peel extract of Flemingia vestita and its major isoflavone, genistein, have been shown to have a vermifugal/vermicidal effect by causing a flaccid paralysis accompanied by alterations in the structural architecture of the tegumental interface and metabolic activity in Raillietina echinobothrida, the cestode of domestic fowl. In the present study, the crude root-peel extract and pure genistein were tested in vitro with respect to Ca2+ homeostasis and the occurrence of some metal ions was detected in the parasite. Live cestodes were incubated in pre-defined concentrations of the crude root-peel extract, genistein and praziquantel (as reference drug), till the paralysis time with simultaneous maintenance of respective controls. In the parasite tissue, a significant amount of Ca2+ (approximately 400 microg/g dry tissue wt) was found to be present besides magnesium, iron, zinc, lead and chromium, whilst manganese, cadmium and nickel were below the level of detection. The Ca2+ concentration was decreased significantly by 39%-49%, in the parasite tissue exposed to the test materials in comparison to the respective controls. There was also an increase in Ca2+ efflux by 91%-160% into the culture medium under similar treatments. The changes in Ca2+ homeostasis may be related to the rapid muscular contraction and consequent paralysis in the parasite due to the anthelmintic stress caused by the phytochemicals of F. vestita.

  1. Anther and stigma morphology in mirror-image flowers of Chamaecrista chamaecristoides (Fabaceae): implications for buzz pollination.

    PubMed

    Arceo-Gómez, G; Martínez, M L; Parra-Tabla, V; García-Franco, J G

    2011-01-01

    Enantiostyly (mirror-image flowers) is usually associated with buzz pollination. In buzz-pollinated flowers, pollen is released through terminal pores after bees vibrate the stamens. Several studies have evaluated the function of 'buzzing' in pollen release, but less attention has been paid to the effect of buzzing on pollen capture and deposition on stigmas. Evaluating the mechanism of pollen dispersion in buzz-pollinated flowers is important because it may affect mating patterns and reproductive success. In this study, we analysed the morphology of sexual organs (anther and stigma) using electron microscopy, and determined the relationship between sexual organ structure and pollen capture function through experimental manipulations of buzz-pollinated flowers of Chamaecrista chamaecristoides, as well as vibration frequencies on floral visitors. Pollen release occurs through two terminal pores at the tip of the stamens. However, unlike most angiosperms that have their stigmatic surface exposed, C. chamaecristoides presents a stigmatic surface inside a cavity covered by trichomes. Experimental manipulations showed that effective fertilisation is only achieved when the style is vibrated, suggesting that buzzing is not only important for pollen release but also for pollen capture and deposition on the stigma. This result, in addition to vibration frequency analysis, suggests that although all floral visitors buzz flowers only those that buzz at higher frequencies achieve effective fertilisation. The anatomical features of sexual organs in flowers of C. chamaecristoides demonstrate that this species possesses a highly specialised, elaborate morphology, with both genders selected for traits that promote buzz pollination. PMID:21134083

  2. Structuralism.

    ERIC Educational Resources Information Center

    Piaget, Jean

    Provided is an overview of the analytical method known as structuralism. The first chapter discusses the three key components of the concept of a structure: the view of a system as a whole instead of so many parts; the study of the transformations in the system; and the fact that these transformations never lead beyond the system but always…

  3. Structure elucidation and antioxidant activity of the phenolic compounds from Rhynchosia suaveolens.

    PubMed

    Rammohan, Aluru; Gunasekar, Duvvuru; Reddy, Netala Vasudeva; Vijaya, Tartte; Devillee, Alexandre; Bodo, Bernard

    2015-04-01

    A new benzophenone, 2-hydroxy-3,4-dimethoxybenzophenone (1), together with a known C-glycosylxanthone, mangiferin (2) and two known C-glycosylflavones, isovitexin (3) and isoorientin (4), were isolated from the flowers of Rhynchosia suaveolens DC. (Fabaceae). The structure of the new compound (1) and the known compounds (2-4) were elucidated by extensive 1D and 2D NMR spectral studies. The plant extracts, as well as the isolated compounds, were evaluated for their total phenolic content (TPC), total flavonoid content (TFC) and DPPH radical scavenging activity. Among the isolated compounds, mangiferin (2) and isoorientin (4) showed significant radical scavenging activity comparable with that of ascorbic acid.

  4. How territoriality and host-tree taxa determine the structure of ant mosaics.

    PubMed

    Dejean, Alain; Ryder, Suzanne; Bolton, Barry; Compin, Arthur; Leponce, Maurice; Azémar, Frédéric; Céréghino, Régis; Orivel, Jérôme; Corbara, Bruno

    2015-06-01

    Very large colonies of territorially dominant arboreal ants (TDAAs), whose territories are distributed in a mosaic pattern in the canopies of many tropical rainforests and tree crop plantations, have a generally positive impact on their host trees. We studied the canopy of an old Gabonese rainforest (ca 4.25 ha sampled, corresponding to 206 "large" trees) at a stage just preceding forest maturity (the Caesalpinioideae dominated; the Burseraceae were abundant). The tree crowns sheltered colonies from 13 TDAAs plus a co-dominant species out of the 25 ant species recorded. By mapping the TDAAs' territories and using a null model co-occurrence analysis, we confirmed the existence of an ant mosaic. Thanks to a large sampling set and the use of the self-organizing map algorithm (SOM), we show that the distribution of the trees influences the structure of the ant mosaic, suggesting that each tree taxon attracts certain TDAA species rather than others. The SOM also improved our knowledge of the TDAAs' ecological niches, showing that these ant species are ecologically distinct from each other based on their relationships with their supporting trees. Therefore, TDAAs should not systematically be placed in the same functional group even when they belong to the same genus. We conclude by reiterating that, in addition to the role played by TDAAs' territorial competition, host trees contribute to structuring ant mosaics through multiple factors, including host-plant selection by TDAAs, the age of the trees, the presence of extrafloral nectaries, and the taxa of the associated hemipterans. PMID:26004265

  5. How territoriality and host-tree taxa determine the structure of ant mosaics

    NASA Astrophysics Data System (ADS)

    Dejean, Alain; Ryder, Suzanne; Bolton, Barry; Compin, Arthur; Leponce, Maurice; Azémar, Frédéric; Céréghino, Régis; Orivel, Jérôme; Corbara, Bruno

    2015-06-01

    Very large colonies of territorially dominant arboreal ants (TDAAs), whose territories are distributed in a mosaic pattern in the canopies of many tropical rainforests and tree crop plantations, have a generally positive impact on their host trees. We studied the canopy of an old Gabonese rainforest (ca 4.25 ha sampled, corresponding to 206 "large" trees) at a stage just preceding forest maturity (the Caesalpinioideae dominated; the Burseraceae were abundant). The tree crowns sheltered colonies from 13 TDAAs plus a co-dominant species out of the 25 ant species recorded. By mapping the TDAAs' territories and using a null model co-occurrence analysis, we confirmed the existence of an ant mosaic. Thanks to a large sampling set and the use of the self-organizing map algorithm (SOM), we show that the distribution of the trees influences the structure of the ant mosaic, suggesting that each tree taxon attracts certain TDAA species rather than others. The SOM also improved our knowledge of the TDAAs' ecological niches, showing that these ant species are ecologically distinct from each other based on their relationships with their supporting trees. Therefore, TDAAs should not systematically be placed in the same functional group even when they belong to the same genus. We conclude by reiterating that, in addition to the role played by TDAAs' territorial competition, host trees contribute to structuring ant mosaics through multiple factors, including host-plant selection by TDAAs, the age of the trees, the presence of extrafloral nectaries, and the taxa of the associated hemipterans.

  6. Early signaling, synthesis, transport and metabolism of ureides.

    PubMed

    Baral, Bikash; Teixeira da Silva, Jaime A; Izaguirre-Mayoral, Maria Luisa

    2016-04-01

    The symbiosis between α nitrogen (N2)-fixing Proteobacteria (family Rhizobiaceae) and legumes belonging to the Fabaceae (a single phylogenetic group comprising three subfamilies: Caesalpinioideae, Mimosoideae and Papilionoideae) results in the formation of a novel root structure called a nodule, where atmospheric N2 is fixed into NH3(+). In the determinate type of nodules harbored by Rhizobium-nodulated Fabaceae species, newly synthesized NH3(+) is finally converted into allantoin (C4H6N4O3) and allantoic acid (C4H8N4O4) (ureides) through complex pathways involving at least 20 different enzymes that act synchronously in two types of nodule cells with contrasting ultrastructure, including the tree nodule cell organelles. Newly synthesized ureides are loaded into the network of nodule-root xylem vessels and transported to aerial organs by the transpirational water current. Once inside the leaves, ureides undergo an enzymatically driven reverse process to yield NH4(+) that is used for growth. This supports the role of ureides as key nitrogen (N)-compounds for the growth and yield of legumes nodulated by Rhizobium that grow in soils with a low N content. Thus, a concrete understanding of the mechanisms underlying ureide biogenesis and catabolism in legumes may help agrobiologists to achieve greater agricultural discoveries. In this review we focus on the transmembranal and transorganellar symplastic and apoplastic movement of N-precursors within the nodules, as well as on the occurrence, localization and properties of enzymes and genes involved in the biogenesis and catabolism of ureides. The synthesis and transport of ureides are not unique events in Rhizobium-nodulated N2-fixing legumes. Thus, a brief description of the synthesis and catabolism of ureides in non-legumes was included for comparison. The establishment of the symbiosis, nodule organogenesis and the plant's control of nodule number, synthesis and translocation of ureides via feed-back inhibition

  7. External morphology and ultra-structure of eggs and first instar of Prepona laertes laertes (Hübner, [1811]), with notes on host plant use and taxonomy.

    PubMed

    Dias, Fernando M S; Casagrande, Mirna M; Mielke, Olaf H H

    2011-01-01

    The external morphology and the tegument ultra-structure of Prepona laertes laertes (Hübner, [1811]) (Lepidoptera: Nymphalidae: Charaxinae) eggs and first instar larvae feeding on Inga spp. (Fabaceae) in a forest fragment in Joinville, Santa Catarina, Brazil, are described. Descriptions of the morphology with illustrations are presented, based upon observations through scanning electron microscopy and stereoscopic and optic microscopes attached to a camera lucida. Descriptions and illustrations of the head capsule, chaetotaxy, tegument, and setae are presented. The taxonomy, morphological characters, and host plant use of Prepona laertes immature stages are discussed.

  8. Long-term effect of carbohydrate reserves on growth and reproduction of Prosopis denudans (Fabaceae): implications for conservation of woody perennials

    PubMed Central

    Vilela, Alejandra E.; Agüero, Paola R.; Ravetta, Damián; González-Paleo, Luciana

    2016-01-01

    Prosopis denudans, an extreme xerophyte shrub, is consumed by ungulates and threatened by firewood gathering, because it is one of the preferred species used by Mapuche indigenous people of Patagonia. In a scenario of uncontrolled use of vegetation, it is very difficult to develop a conservation plan that jointly protects natural resources and its users. We performed a field experiment to assess the impact of defoliation on growth, reproduction and stores of a wild population of P. denudans. We imposed four levels of defoliation (removal of 100, 66, 33 and 0% of leaves) and evaluated the short- and long-term (3 years) effects of this disturbance. Seasonal changes in shoot carbohydrates suggested that they support leaf-flush and blooming. Severely defoliated individuals also used root reserves to support growth and leaf-flush after clipping. Vegetative growth was not affected by defoliation history. Leaf mass area increased after the initial clipping, suggesting the development of structural defenses. The depletion of root reserves at the end of the first year affected inflorescence production the following spring. We conclude that P. denudans shrubs could lose up to one-third of their green tissues without affecting growth or inflorescence production. The removal of a higher proportion of leaves will diminish stores, which in turn, will reduce or completely prevent blooming and, therefore, fruit production the following seasons. Very few studies integrate conservation and plant physiology, and we are not aware, so far, of any work dealing with long-term plant carbon economy of a long-lived perennial shrub as an applied tool in conservation. These results might help the development of management strategies that consider both the use and the conservation of wild populations of P. denudans. PMID:27293747

  9. Long-term effect of carbohydrate reserves on growth and reproduction of Prosopis denudans (Fabaceae): implications for conservation of woody perennials.

    PubMed

    Vilela, Alejandra E; Agüero, Paola R; Ravetta, Damián; González-Paleo, Luciana

    2016-01-01

    Prosopis denudans, an extreme xerophyte shrub, is consumed by ungulates and threatened by firewood gathering, because it is one of the preferred species used by Mapuche indigenous people of Patagonia. In a scenario of uncontrolled use of vegetation, it is very difficult to develop a conservation plan that jointly protects natural resources and its users. We performed a field experiment to assess the impact of defoliation on growth, reproduction and stores of a wild population of P. denudans. We imposed four levels of defoliation (removal of 100, 66, 33 and 0% of leaves) and evaluated the short- and long-term (3 years) effects of this disturbance. Seasonal changes in shoot carbohydrates suggested that they support leaf-flush and blooming. Severely defoliated individuals also used root reserves to support growth and leaf-flush after clipping. Vegetative growth was not affected by defoliation history. Leaf mass area increased after the initial clipping, suggesting the development of structural defenses. The depletion of root reserves at the end of the first year affected inflorescence production the following spring. We conclude that P. denudans shrubs could lose up to one-third of their green tissues without affecting growth or inflorescence production. The removal of a higher proportion of leaves will diminish stores, which in turn, will reduce or completely prevent blooming and, therefore, fruit production the following seasons. Very few studies integrate conservation and plant physiology, and we are not aware, so far, of any work dealing with long-term plant carbon economy of a long-lived perennial shrub as an applied tool in conservation. These results might help the development of management strategies that consider both the use and the conservation of wild populations of P. denudans. PMID:27293747

  10. Long-term effect of carbohydrate reserves on growth and reproduction of Prosopis denudans (Fabaceae): implications for conservation of woody perennials.

    PubMed

    Vilela, Alejandra E; Agüero, Paola R; Ravetta, Damián; González-Paleo, Luciana

    2016-01-01

    Prosopis denudans, an extreme xerophyte shrub, is consumed by ungulates and threatened by firewood gathering, because it is one of the preferred species used by Mapuche indigenous people of Patagonia. In a scenario of uncontrolled use of vegetation, it is very difficult to develop a conservation plan that jointly protects natural resources and its users. We performed a field experiment to assess the impact of defoliation on growth, reproduction and stores of a wild population of P. denudans. We imposed four levels of defoliation (removal of 100, 66, 33 and 0% of leaves) and evaluated the short- and long-term (3 years) effects of this disturbance. Seasonal changes in shoot carbohydrates suggested that they support leaf-flush and blooming. Severely defoliated individuals also used root reserves to support growth and leaf-flush after clipping. Vegetative growth was not affected by defoliation history. Leaf mass area increased after the initial clipping, suggesting the development of structural defenses. The depletion of root reserves at the end of the first year affected inflorescence production the following spring. We conclude that P. denudans shrubs could lose up to one-third of their green tissues without affecting growth or inflorescence production. The removal of a higher proportion of leaves will diminish stores, which in turn, will reduce or completely prevent blooming and, therefore, fruit production the following seasons. Very few studies integrate conservation and plant physiology, and we are not aware, so far, of any work dealing with long-term plant carbon economy of a long-lived perennial shrub as an applied tool in conservation. These results might help the development of management strategies that consider both the use and the conservation of wild populations of P. denudans.

  11. New species of Elaphomyces (Elaphomycetaceae, Eurotiales, Ascomycota) from tropical rainforests of Cameroon and Guyana.

    PubMed

    Castellano, Michael A; Dentinger, Bryn T M; Séné, Olivier; Elliott, Todd F; Truong, Camille; Henkel, Terry W

    2016-06-01

    The sequestrate false truffles Elaphomyces favosus, E. iuppitercellus, and E. labyrinthinus spp. nov. are described as new to science from the Dja Biosphere Reserve, Cameroon. Elaphomyces adamizans sp. nov. is described as new from the Pakaraima Mountains of Guyana. The Cameroonian species are the first Elaphomyces taxa to be formally described from Africa, occurring in lowland Guineo-Congolian tropical rainforests dominated by the ectomycorrhizal (ECM) canopy tree Gilbertiodendron dewevrei (Fabaceae subfam. Caesalpinioideae). The Guyanese species is the third to be discovered in lowland tropical South America, occurring in forests dominated by the ECM trees Pakaraimaea dipterocarpacea (Dipterocarpaceae) and Dicymbe jenmanii (Fabaceae subfam. Caesalpinioideae). Macromorphological, micromorphological, habitat, and DNA sequence data are provided for each new species. Molecular and morphological data place these fungi in Elaphomycetaceae (Eurotiales, Ascomycota). Unique morphological features are congruent with molecular delimitation of each of the new species based on a phylogenetic analysis of the rDNA ITS and 28S loci across the Elaphomycetaceae. The phylogenetic analysis also suggests that a common ancestor is shared between some Elaphomyces species from Africa and South America, and that species of the stalked, volvate genus Pseudotulostoma may be nested in Elaphomyces.

  12. New species of Elaphomyces (Elaphomycetaceae, Eurotiales, Ascomycota) from tropical rainforests of Cameroon and Guyana.

    PubMed

    Castellano, Michael A; Dentinger, Bryn T M; Séné, Olivier; Elliott, Todd F; Truong, Camille; Henkel, Terry W

    2016-06-01

    The sequestrate false truffles Elaphomyces favosus, E. iuppitercellus, and E. labyrinthinus spp. nov. are described as new to science from the Dja Biosphere Reserve, Cameroon. Elaphomyces adamizans sp. nov. is described as new from the Pakaraima Mountains of Guyana. The Cameroonian species are the first Elaphomyces taxa to be formally described from Africa, occurring in lowland Guineo-Congolian tropical rainforests dominated by the ectomycorrhizal (ECM) canopy tree Gilbertiodendron dewevrei (Fabaceae subfam. Caesalpinioideae). The Guyanese species is the third to be discovered in lowland tropical South America, occurring in forests dominated by the ECM trees Pakaraimaea dipterocarpacea (Dipterocarpaceae) and Dicymbe jenmanii (Fabaceae subfam. Caesalpinioideae). Macromorphological, micromorphological, habitat, and DNA sequence data are provided for each new species. Molecular and morphological data place these fungi in Elaphomycetaceae (Eurotiales, Ascomycota). Unique morphological features are congruent with molecular delimitation of each of the new species based on a phylogenetic analysis of the rDNA ITS and 28S loci across the Elaphomycetaceae. The phylogenetic analysis also suggests that a common ancestor is shared between some Elaphomyces species from Africa and South America, and that species of the stalked, volvate genus Pseudotulostoma may be nested in Elaphomyces. PMID:27433441

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

    PubMed

    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.

  14. Reproductive Biology of Butea monosperma (Fabaceae)

    PubMed Central

    TANDON, RAJESH; SHIVANNA, K. R.; MOHAN RAM, H. Y.

    2003-01-01

    The reproductive biology encompassing phenology, floral biology, pollination and breeding systems, of Butea monosperma, a beautiful tree of the Indian subcontinent, was investigated in a protected dry, deciduous forest located in New Delhi. Phenological studies indicated that although the species shows a regular flowering season, all trees do not flower every year. Flowers are typically papilionaceous; the stigma is wet papillate and the style is hollow. The flowers show characteristics of bird pollination being large and bright orange‐red in colour with copious amounts of nectar, and exhibiting diurnal anthesis. Although the flowers are frequented by as many as seven species of birds belonging to six families, only one species, the purple sunbird (Nectarinia asiatica), is the effective pollinator. The flowers are also pollinated by the three‐striped squirrel (Funambulus tristiatus). Unlike other flower visitors, these two pollinators forage the nectar from the open side of the keel (legitimate path) during which pollen grains are deposited on their body parts. After the first visit of a sunbird or a squirrel, virgin flowers showed pollen load on the stigma and developed into fruits. B. monosperma shows a weak form of self‐incompatibility. Fruit set following manual self‐pollination (5·25 %) was comparable with open‐pollination (approx. 5 %) but was significantly lower than manual cross‐pollination (22·51 %). This indicates that there is a high degree of geitonogamous pollination in this species, which may lead to a weakening of self‐incompatibility as a means of reproductive assurance. The results are analysed in the light of prevailing discussions on specialized vs. generalized pollination systems. PMID:14500327

  15. Reproductive biology of Butea monosperma (Fabaceae).

    PubMed

    Tandon, Rajesh; Shivanna, K R; Mohan Ram, H Y

    2003-11-01

    The reproductive biology encompassing phenology, floral biology, pollination and breeding systems, of Butea monosperma, a beautiful tree of the Indian subcontinent, was investigated in a protected dry, deciduous forest located in New Delhi. Phenological studies indicated that although the species shows a regular flowering season, all trees do not flower every year. Flowers are typically papilionaceous; the stigma is wet papillate and the style is hollow. The flowers show characteristics of bird pollination being large and bright orange-red in colour with copious amounts of nectar, and exhibiting diurnal anthesis. Although the flowers are frequented by as many as seven species of birds belonging to six families, only one species, the purple sunbird (Nectarinia asiatica), is the effective pollinator. The flowers are also pollinated by the three-striped squirrel (Funambulus tristiatus). Unlike other flower visitors, these two pollinators forage the nectar from the open side of the keel (legitimate path) during which pollen grains are deposited on their body parts. After the first visit of a sunbird or a squirrel, virgin flowers showed pollen load on the stigma and developed into fruits. B. monosperma shows a weak form of self-incompatibility. Fruit set following manual self-pollination (5.25 %) was comparable with open-pollination (approx. 5 %) but was significantly lower than manual cross-pollination (22.51 %). This indicates that there is a high degree of geitonogamous pollination in this species, which may lead to a weakening of self-incompatibility as a means of reproductive assurance. The results are analysed in the light of prevailing discussions on specialized vs. generalized pollination systems.

  16. Charcoal records reveal past occurrences of disturbances in the forests of the Kisangani region, Democratic Republic of the Congo

    NASA Astrophysics Data System (ADS)

    Tshibamba Mukendi, John; Hubau, Wannes; Ntahobavuka, Honorine; Boyemba Bosela, Faustin; De Cannière, Charles; Beeckman, Hans

    2014-05-01

    Past disturbances have modified local density, structure and floristic composition of Central African rainforests. As such, these perturbations represent a driving force for forest dynamics and they were presumably at the origin of present-day forest mosaics. One of the most prominent disturbances within the forest is fire, leaving behind charcoal as a witness of past forest dynamics. Quantification and identification of ancient charcoal fragments found in soil layers (= pedoanthracology) allows a detailed reconstruction of forest history, including the possible occurrence of past perturbations. The primary objective of this study is to present palaeoenvironmental evidence for the existence of past disturbances in the forests of the Kisangani region (Democratic Republic of the Congo) using a pedoanthracological approach. We quantified and identified charcoal fragments from pedoanthracological excavations in the Yangambi, Yoko, Masako and Kole forest regions. Charcoal sampling was conducted in pit intervals of 10 cm, whereby pottery fragments were also registered and quantified. Floristic identifications were conducted using former protocols based on wood anatomy, which is largely preserved after charcoalification. 14 excavations were conducted and charcoal was found in most pit intervals. Specifically, 52 out of 56 sampled intervals from the Yangambi forest contained charcoal, along with 47 pit intervals from the Yoko forest reserve, 34 pit intervals from the Masako forest and 16 from the Kole forest. Highest specific anthracomasses were recorded in Yoko (167 mg charcoal per kg soil), followed by Yangambi (133 mg/kg), Masako (71,89 mg/kg) and finally Kole (42,4 mg/kg). Charcoal identifications point at a manifest presence of the family of Fabaceae (Caesalpinioideae). This family is characteristic for the tropical humid rainforest. The presence of charcoal fragments from these taxa, associated with pottery sherds on different depths within the profiles, suggests

  17. Post-zygotic Reproductive Isolation Between Sympatric Taxa in the Chamaecrista desvauxii Complex (Leguminosae–Caesalpinioideae)

    PubMed Central

    Costa, Cristiana Barros Nascimento; Lambert, Sabrina Mota; Borba, Eduardo Leite; de Queiroz, Luciano Paganucci

    2007-01-01

    Background and Aims Differences in the mating systems and the mechanisms of reproductive isolation between Chamaecrista desvauxii var. graminea and C. desvauxii var. latistipula were examined in the Chapada Diamantina, Brazil. These taxa occur sympatrically, and their populations demonstrate marked morphological differences. The objective of the present work was to determine if reproductive isolation mechanisms exist between these two populations of C. desvauxii, and to determine the influence of these putative mechanisms on their genetic differentiation. Methods Field observations were made of floral biology, phenology and floral visitation, and experiments on intra- and interpopulation pollination and germination rates of the resultant seeds were performed. A genetic examination of the populations was undertaken using four allozyme loci. Key Results The varieties examined demonstrated overlapping of flowering periods during the months of June to September. The main pollinator for both varieties was the bee Bombus brevivillus. Both varieties are self-compatible, and a large number of fruits are formed in cross-pollinations with high seed germination rates. Inter-taxa pollinations result in high levels of fruit production, but no seeds are formed. Two of the four loci examined were diagnostic for the varieties, and exclusive high-frequency alleles were encountered at the other loci, leading to a high genetic distance between the two populations (0·495). Conclusions Pre-zygotic barriers were not found between the two varieties, and these remain isolated due to post-zygotic events. The two varieties demonstrate marked differences in their morphology, floral biology, phenology and genetic make-up, all of which indicate that they should be treated as two distinct species. A complete revision involving the other varieties of the C. desvauxii complex will be necessary in order to define these two taxa formally. PMID:17331960

  18. Cryptic Speciation in the Caesalpinia hintonii Complex (Leguminosae: Caesalpinioideae) in a Seasonally Dry Mexican Forest

    PubMed Central

    Sotuyo, Solange; Delgado-Salinas, Alfonso; Chase, Mark W.; Lewis, Gwilym P.; Oyama, Ken

    2007-01-01

    Backgroud and Aims The Caesalpinia hintonii group comprises six species of endemic shrubs or trees, C. epifanioi, C. hintonii, C. laxa, C. macvaughii, C. melanadenia and C. oyamae, found in scattered patches of seasonally dry forest in the Río Balsas depression and the neighbouring Tehuacán–Cuicatlán valley, which are part of the Mexican morphotectonic province of Sierra Madre del Sur. An evaluation is made of phylogeographic patterns and genetic diversity with a phylogenetic analysis of the C. hintonii complex in order to study the dynamics of speciation in this endemic group of legumes. Methods A phylogeographic study based on four highly variable non-coding plastid regions (trnL intron, trnL-F intergenic spacer, trnH-psbA intergenic spacer, and accD-psaI intergenic spacer) was carried out for the Caesalpinia hintonii complex. Five of the six taxa of the C. hintonii complex were included. Key Results and Conclusions The plastid analyses involving multiple accessions of each taxon from throughout their ranges resolved C. epifanioi and C. hintonii as well-supported clusters, but C. oyamae has two unexpectedly divergent lineages. Two well-supported geographic clades: eastern (C. epifanioi, C. melanadenia and C. oyamae) and western (C. hintonii and C. macvaughii) were established. The analyses performed provide evidence of recent morphostatic radiation in C. oyamae resulting from isolation and local adaptation. This pattern of genetic differentiation without morphological divergence may be a model that fits many groups of tropical woody taxa inhabiting similarly dry forests subjected to shifting selection. PMID:17913727

  19. Karyomorphology and karyotype asymmetry in the South American Caesalpinia species (Leguminosae and Caesalpinioideae).

    PubMed

    Rodrigues, P S; Souza, M M; Corrêa, R X

    2014-10-20

    With the purpose of addressing the pattern of karyotype evolution in Caesalpinia species, chromosome morphology was characterized in five species from Brazil, and karyotypic asymmetry was analyzed in 14 species from South America. All accessions had the chromosome number 2n = 24, which was first described here for Caesalpinia laxiflora Tul. and Cenostigma macrophyllum Tul. The karyotype formula of C. laxiflora, Caesalpinia pyramidalis Tul., and C. macrophyllum was 12 m. The formula varies amongst the populations of Caesalpinia bracteosa Tul. (11 m + 1 sm) and Caesalpinia echinata Lam. (10 m + 2 sm and 9 m + 3 sm). The intra- and interspecific variations in chromosome length were significant (analysis of variance, P < 0.05). Analyzing the asymmetry index (AI), revealed that Caesalpinia calycina Benth. had the most asymmetrical karyotype (AI = 10.52), whereas Caesalpinia paraguarienses (D. Parodi) Burkat. and Caesalpinia gilliesii (Hook.) Benth. had the most symmetrical karyotypes (AI = 0.91 and 1.10, respectively). There has been a trend to lower AI values for the Caesalpinia s.l. species assigned in Libidibia and intermediate values for those combined into Poincianella. On the other hand, the karyotypes of Erythrostemon species had extremely different AI values. This study confirms the existence of karyotype variability in Caesalpinia s.l. while revealing a possible uniformity of this trait in some of the new genera that are being divided from Caesalpinia s.l. More broadly, the 2n = 24 chromosome number is conserved. Metacentric chromosomes and low AI values predominate among Caesalpinia s.l. and Cenostigma.

  20. Structure elucidation and DNA binding specificity of natural compounds from Cassia siamea leaves: A biophysical approach.

    PubMed

    Parveen, Mehtab; Ahmad, Faheem; Malla, Ali Mohammed; Khan, Mohd Sohrab; Rehman, Sayeed Ur; Tabish, Mohammad; Silva, Manuela Ramos; Silva, P S Pereira

    2016-06-01

    A novel isoflavone, 5,6,7-trimethoxy-3-(3',4',5'-trimethoxyphenyl)-4H-chromen-4-one (1) along with a known pyranocoumarin, Seselin (2) have been isolated from the ethanolic extract of the leaves of Cassia siamea (Family: Fabaceae). Compound 1 has been reported for the first time from any natural source and has not been synthesized so far. Their structures were elucidated on the basis of chemical and physical evidences viz. elemental analysis, UV, FT-IR, (1)H-NMR, (13)C-NMR and mass spectral analysis. Structure of compound (1) was further authenticated by single-crystal X-ray analysis and density functional theory (DFT) calculations. A multi-technique approach employing UV-Visible spectroscopy, fluorescence, KI quenching studies, competitive displacement assay, circular dichroism and viscosity studies have been utilized to probe the extent of interaction and possible binding modes of isolated compounds (1-2) with calf thymus DNA (CT-DNA). Both the compounds were found to interact with DNA via non-intercalative binding mode with moderate proficiencies. Groove binding was the major interaction mode in the case of compound 2 while compound 1 probably interacts with DNA through electrostatic interactions. These studies provide deeper insight in understanding of DNA-drug (natural products) interaction which could be helpful to improve their bioavailability for therapeutic purposes. PMID:27085054

  1. 3,6-Dimethoxy-6″,6″-Dimethyl-(7,8,2″,3″)-Chromeneflavone, a Flavonoid Isolated from Lonchocarpus Araripensis Benth. (Fabaceae), Reduces Nociceptive Behaviour in Mice.

    PubMed

    Almeida, Jackson R G S; Silva, Juliane C; Guimarães, Amanda L; Oliveira, Ana P; Souza, Grasielly R; Oliveira-Júnior, Raimundo G; Lima-Saraiva, Sarah R G; Barbosa-Filho, José M; Braz-Filho, Raimundo; Queiroz, Dinalva Brito; Botelho, Marco Antônio

    2015-10-01

    Lonchocarpus araripensis Benth. is largely distributed in the northeast region of Brazil. It is popularly known as 'sucupira'. Recent studies have shown that some species of Lonchocarpus have interesting pharmacological activities. In this study, we evaluated the antinociceptive effect of a flavone isolated from L. araripensis. The chemical examination resulted in the isolation of 3,6-dimethoxy-6″,6″-dimethyl-(7,8,2″,3″)-chromeneflavone (DDF). The structure of the compound was established by spectral analysis. Antinociceptive activity of DDF was evaluated by measuring nociception by acetic acid, formalin and hot plate tests. The rota rod test was used to evaluate motor coordination. The results demonstrated that DDF was able to prevent acetic-acid-writhing-induced nociception (p < 0.001) in mice. Furthermore, DDF produced a significant reduction of the nociceptive behaviour at the early and late phases of paw licking in the formalin test. Also, DDF produced an inhibition of the nociceptive behaviour during a hot-plate test. No alteration in motor coordination was observed. These results confirm the hypothesis that DDF reduces the nociceptive behaviour in mice, probably through central mechanisms, but without compromising the motor coordination of animals.

  2. Crystal Structures and Binding Dynamics of Odorant-Binding Protein 3 from two aphid species Megoura viciae and Nasonovia ribisnigri.

    PubMed

    Northey, Tom; Venthur, Herbert; De Biasio, Filomena; Chauviac, Francois-Xavier; Cole, Ambrose; Ribeiro, Karlos Antonio Lisboa; Grossi, Gerarda; Falabella, Patrizia; Field, Linda M; Keep, Nicholas H; Zhou, Jing-Jiang

    2016-01-01

    Aphids use chemical cues to locate hosts and find mates. The vetch aphid Megoura viciae feeds exclusively on the Fabaceae, whereas the currant-lettuce aphid Nasonovia ribisnigri alternates hosts between the Grossulariaceae and Asteraceae. Both species use alarm pheromones to warn of dangers. For N. ribisnigri this pheromone is a single component (E)-β-farnesene but M. viciae uses a mixture of (E)-β-farnesene, (-)-α-pinene, β-pinene, and limonene. Odorant-binding proteins (OBP) are believed to capture and transport such semiochemicals to their receptors. Here, we report the first aphid OBP crystal structures and examine their molecular interactions with the alarm pheromone components. Our study reveals some unique structural features: 1) the lack of an internal ligand binding site; 2) a striking groove in the surface of the proteins as a putative binding site; 3) the N-terminus rather than the C-terminus occupies the site closing off the conventional OBP pocket. The results from fluorescent binding assays, molecular docking and dynamics demonstrate that OBP3 from M. viciae can bind to all four alarm pheromone components and the differential ligand binding between these very similar OBP3s from the two aphid species is determined mainly by the direct π-π interactions between ligands and the aromatic residues of OBP3s in the binding pocket. PMID:27102935

  3. Crystal Structures and Binding Dynamics of Odorant-Binding Protein 3 from two aphid species Megoura viciae and Nasonovia ribisnigri

    PubMed Central

    Northey, Tom; Venthur, Herbert; De Biasio, Filomena; Chauviac, Francois-Xavier; Cole, Ambrose; Ribeiro, Karlos Antonio Lisboa; Grossi, Gerarda; Falabella, Patrizia; Field, Linda M.; Keep, Nicholas H.; Zhou, Jing-Jiang

    2016-01-01

    Aphids use chemical cues to locate hosts and find mates. The vetch aphid Megoura viciae feeds exclusively on the Fabaceae, whereas the currant-lettuce aphid Nasonovia ribisnigri alternates hosts between the Grossulariaceae and Asteraceae. Both species use alarm pheromones to warn of dangers. For N. ribisnigri this pheromone is a single component (E)-β-farnesene but M. viciae uses a mixture of (E)-β-farnesene, (−)-α-pinene, β-pinene, and limonene. Odorant-binding proteins (OBP) are believed to capture and transport such semiochemicals to their receptors. Here, we report the first aphid OBP crystal structures and examine their molecular interactions with the alarm pheromone components. Our study reveals some unique structural features: 1) the lack of an internal ligand binding site; 2) a striking groove in the surface of the proteins as a putative binding site; 3) the N-terminus rather than the C-terminus occupies the site closing off the conventional OBP pocket. The results from fluorescent binding assays, molecular docking and dynamics demonstrate that OBP3 from M. viciae can bind to all four alarm pheromone components and the differential ligand binding between these very similar OBP3s from the two aphid species is determined mainly by the direct π-π interactions between ligands and the aromatic residues of OBP3s in the binding pocket. PMID:27102935

  4. Paths of water entry and structures involved in the breaking of seed dormancy of Lupinus.

    PubMed

    Robles-Díaz, Erika; Flores, Joel; Yáñez-Espinosa, Laura

    2016-03-15

    Physical dormancy is the water impermeability of the seed coat caused by one or more palisade cell layer(s) called macrosclereids. The specialised structure for water entry sites is the water gap, which serves as a detector of environmental cues for germination. In Fabaceae, the water gap is the lens, although another seed structure for water entry could exist. In this study, we identified the initial site of water entry, observed the hydration of a cushion-like structure near the radicle, described the anatomy of the water gap, and analysed the association of anatomical seed traits with the initial site of water entry and the imbibition velocity of six species of Lupinus from the state of Jalisco, Mexico. Dye tracking with a toluidine blue solution was used to identify the initial site of water entry. The anatomical description was performed using conventional microtechnique and a light microscope. The entry of the toluidine solution into seeds of L. montanus was observed after 6h, followed by L. exaltatus and L. mexicanus after 18h and L. elegans, L. reflexus and L. rotundiflorus after 48h. The site of water entry was the lens in L. elegans, L. exaltatus, L. reflexus and L. rotundiflorus and the micropyle in L. mexicanus and L. montanus. The cushion-like structure was responsible for water accumulation in embryo imbibition. Significant differences among anatomical seed traits such as thickness in the hilar region, the counter-palisade layer, cushion-like structure, epidermis, hypodermis, and innermost parenchyma layer were found among the species.

  5. Paths of water entry and structures involved in the breaking of seed dormancy of Lupinus.

    PubMed

    Robles-Díaz, Erika; Flores, Joel; Yáñez-Espinosa, Laura

    2016-03-15

    Physical dormancy is the water impermeability of the seed coat caused by one or more palisade cell layer(s) called macrosclereids. The specialised structure for water entry sites is the water gap, which serves as a detector of environmental cues for germination. In Fabaceae, the water gap is the lens, although another seed structure for water entry could exist. In this study, we identified the initial site of water entry, observed the hydration of a cushion-like structure near the radicle, described the anatomy of the water gap, and analysed the association of anatomical seed traits with the initial site of water entry and the imbibition velocity of six species of Lupinus from the state of Jalisco, Mexico. Dye tracking with a toluidine blue solution was used to identify the initial site of water entry. The anatomical description was performed using conventional microtechnique and a light microscope. The entry of the toluidine solution into seeds of L. montanus was observed after 6h, followed by L. exaltatus and L. mexicanus after 18h and L. elegans, L. reflexus and L. rotundiflorus after 48h. The site of water entry was the lens in L. elegans, L. exaltatus, L. reflexus and L. rotundiflorus and the micropyle in L. mexicanus and L. montanus. The cushion-like structure was responsible for water accumulation in embryo imbibition. Significant differences among anatomical seed traits such as thickness in the hilar region, the counter-palisade layer, cushion-like structure, epidermis, hypodermis, and innermost parenchyma layer were found among the species. PMID:26874334

  6. Pollination ecology of the rare desert species Eremosparton songoricum (Fabaceae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pollination ecology of Eremosparton songoricum (Litv.) Vass., a rare desert species endemic to central Asia, was examined by a series of observational studies and manipulative experiments in two natural populations during 2007–2008. Results showed that the duration of flowering lasted 21 and 23 ...

  7. Microsatellite markers for the yam bean Pachyrhizus (Fabaceae)1

    PubMed Central

    Delêtre, Marc; Soengas, Beatriz; Utge, José; Lambourdière, Josie; Sørensen, Marten

    2013-01-01

    • Premise of the study: Microsatellite loci were developed for the understudied root crop yam bean (Pachyrhizus spp.) to investigate intraspecific diversity and interspecific relationships within the genus Pachyrhizus. • Methods and Results: Seventeen nuclear simple sequence repeat (SSR) markers with perfect di- and trinucleotide repeats were developed from 454 pyrosequencing of SSR-enriched genomic libraries. Loci were characterized in P. ahipa and wild and cultivated populations of four closely related species. All loci successfully cross-amplified and showed high levels of polymorphism, with number of alleles ranging from three to 12 and expected heterozygosity ranging from 0.095 to 0.831 across the genus. • Conclusions: By enabling rapid assessment of genetic diversity in three native neotropical crops, P. ahipa, P. erosus, and P. tuberosus, and two wild relatives, P. ferrugineus and P. panamensis, these markers will allow exploration of the genetic diversity and evolutionary history of the genus Pachyrhizus. PMID:25202568

  8. Alysicarpus poklianus (Fabaceae, Desmodieae), a new species from India

    PubMed Central

    Gholami, Akram; Pandey, Arun K.

    2016-01-01

    Abstract A new species, Alysicarpus poklianus Gholami & Pandey from Sinhgarh, Maharashtra, India is described. It is morphologically most similar to Alysicarpus hamosus but differs in having ovate leaves, rounded-ovate bracts, larger size of calyx, pods comprising 5–7 longer than broad joints with easily separable septa. In this study, a comprehensive description, and identification key of Alysicarpus poklianus are provided.

  9. Water Transport in the Liana Bauhinia fassoglensis (Fabaceae) 1

    PubMed Central

    Ewers, Frank W.; Fisher, Jack B.; Chiu, Shau-Ting

    1989-01-01

    To determine the efficiency of xylem conductance in the liana (woody vine) Bauhinia fassoglensis Kotschy ex Schweinf., we measured hydraulic conductance per unit stem length (measured Kh), leaf-specific conductivity (LSC = Kh/distal leaf area), transpiration rate (E), xylem water potential (ε), vessel number, and vessel diameter. The measured Kh was 49% (se = 7%) of the predicted Kh from Poiseuille's law. The mean LSC for unbranched stem segments was 1.10 × 10−8 square meters per megapascal per second (se = 0.07). LSCs were much lower (about 0.2) at branch junctions. At midday, with E at 7 × 10−8 meters per second, the measured drop in ε was about 0.08 megapascal per meter along the stems and branches and about 0.27 megapascal in going from stem to leaf. In addition, there was a drop of about 0.20 megapascal at branch junctions as predicted by E/LSC. In diurnal measurements leaf ε never dropped below about −1.2 megapascal. For long (e.g. 16 meters) stems, the predicted mid-day drop in ε through the xylem transport system might be great enough to have substantial physiological impact. PMID:16667227

  10. [Desiccation tolerance in seeds of Prosopisferox and Pterogyne nitens (Fabaceae)].

    PubMed

    Morandini, Marcelo Nahuel; Giamminola, Eugenia Mabel; de Viana, Marta Leonor

    2013-03-01

    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 ferox at the National Park Los Cardones and from two sites (Orán and Rivadavia) for P nitens. Desiccation tolerance was assessed following previous established methodologies. The moisture content (MC) of the seeds was determined by keeping them in oven at 103 degreeC and weighting the samples at different intervals till constant weight. Germination essays were carried out with two treatments (control and scarification), with different seed MC (fresh, 10-12%, 3-5%) and in desiccated seeds (3-5% MC) stored six months at -20 degreeC. The MC in P ferox seeds was 14.2% and 10% in P nitens, for both populations studied. Percentage germination in P ferox was higher in the scarification treatments (<82%). The difference between treatments increased with the reduction in MC and the storage for six months at -20 degreeC. Fresh seeds of P nitens do not need scarification treatment, but it is required with the reduction in MC and storage. Mean germination percentage of desiccated seeds stored six months at -20 degreeC was similar in both populations and greater than 82%.We concluded that both species are probably orthodox because seeds tolerated desiccation to 3-5% and storage for six months at -20 degree C. PMID:23894986

  11. Alysicarpus poklianus (Fabaceae, Desmodieae), a new species from India

    PubMed Central

    Gholami, Akram; Pandey, Arun K.

    2016-01-01

    Abstract A new species, Alysicarpus poklianus Gholami & Pandey from Sinhgarh, Maharashtra, India is described. It is morphologically most similar to Alysicarpus hamosus but differs in having ovate leaves, rounded-ovate bracts, larger size of calyx, pods comprising 5–7 longer than broad joints with easily separable septa. In this study, a comprehensive description, and identification key of Alysicarpus poklianus are provided. PMID:27698578

  12. Phylogenetic relationships among morphotypes of Caesalpinia echinata Lam. (Caesalpinioideae: Leguminosae) evidenced by trnL intron sequences

    NASA Astrophysics Data System (ADS)

    Juchum, Fabrício Sacramento; Costa, Marco Antônio; Amorim, André Márcio; Corrêa, Ronan Xavier

    2008-11-01

    Caesalpinia echinata (brazilwood or Pernambuco wood) comprises a complex of three morphological leaf variants, characterized by differences in the number and size of the pinnae and leaflets, and occurring in allopatric and sympatric populations. The present study evaluates the utility of the chloroplast DNA trnL intron in a phylogenetic analysis of the three leaf variants along with other species of Caesalpinia and generic relatives. Our study supports the hypothesis that the name C. echinata designates a species complex and provides evidence that one of the forms, the highly divergent C. echinata large-leafleted variant, represents a distinct taxon.

  13. Spatial structure and the effects of host and soil environments on communities of ectomycorrhizal fungi in wooded savannas and rain forests of Continental Africa and Madagascar.

    PubMed

    Tedersoo, Leho; Bahram, Mohammad; Jairus, Teele; Bechem, Eneke; Chinoya, Stephen; Mpumba, Rebecca; Leal, Miguel; Randrianjohany, Emile; Razafimandimbison, Sylvain; Sadam, Ave; Naadel, Triin; Kõljalg, Urmas

    2011-07-01

    Mycorrhizal fungi play a key role in mineral nutrition of terrestrial plants, but the factors affecting natural distribution, diversity and community composition of particularly tropical fungi remain poorly understood. This study addresses shifts in community structure and species frequency of ectomycorrhizal (EcM) fungi in relation to host taxa, soil depth and spatial structure in four contrasting African ecosystems. We used the rDNA and plastid trnL intron sequence analysis for identification of fungi and host plants, respectively. By partitioning out spatial autocorrelation in plant and fungal distribution, we suggest that African EcM fungal communities are little structured by soil horizon and host at the plant species and family levels. These findings contrast with patterns of vegetation in these forests and EcM fungal communities in other tropical and temperate ecosystems. The low level of host preference indirectly supports an earlier hypothesis that pioneer Phyllanthaceae may facilitate the establishment of late successional Fabaceae and potentially other EcM host trees by providing compatible fungal inoculum in deforested and naturally disturbed ecosystems of tropical Africa.

  14. Sarcodon in the Neotropics II: four new species from Colombia and a key to the regional species.

    PubMed

    Grupe, Arthur C; Vasco-Palacios, Aída Marcela; Smith, Matthew E; Boekhout, Teun; Henkel, Terry W

    2016-01-01

    This work reports on four species of the ectomycorrhizal (ECM) tooth fungus genus Sarcodon (Bankeraceae, Thelephorales, Basidiomycota) recently discovered in the Colombian Amazon. Sarcodon colombiensis sp. nov., Sarcodon rufobrunneus sp. nov., Sarcodon pallidogriseus sp. nov. and Sarcodon bairdii sp. nov. are described as new to science. These fungi occur in forests dominated by ECM trees in the genera Pseudomonotes (Dipterocarpaceae), Dicymbe (Fabaceae subfam. Caesalpinioideae) and Aldina (Fabaceae subfam. Papilionoideae). These records bring the number of Sarcodon species known from the Neotropics to 10. Each of the new species possesses the accepted diagnostic characters for the genus: pileate-stipitate stature, a dentate hymenophore, determinate basidiomata development, fleshy, non-zonate context, and brown, tuberculate basidiospores. Molecular phylogenetic analysis corroborated the generic placement of the species, and, in combination with morphological characters, confirmed that they are new to science. Macromorphological, micromorphological, habitat and DNA sequence data from the nuc rDNA internal transcribed spacer region (ITS) are provided for each of the new species. A key is provided that allows identification of all known Neotropical Sarcodon species and similar extralimital taxa. PMID:27091388

  15. [Floristic composition and structure of a premontane moist forest in Central Valley of Costa Rica].

    PubMed

    Cascante, A; Estrada, A

    2001-03-01

    The floristic composition and structure of a premontane moist forest remnant were studied in the El Rodeo Protected Zone, Central Valley of Costa Rica. Three one-hectare plots were established in the non-disturbed forest, and all trees with a diameter at breast height (dbh) of 10 cm or greater were marked, measured and identified. The plots were located within a radius of 500 m from each other. A total of 106 tree species were recorded in the three plots. Average values: species richness 69.6 species ha-1, abundance 509 individuals ha-1, basal area 36.35 m2 ha-1. Total diversity was 3.54 (Shannon Index, H'), and the species similarity among the plots ranged between S = 0.68 and 0.70 (Sørensen Similarity Index). Most tree species are represented by few individuals (five or less). There is a lack of emergent trees and arborescent palms in the forest canopy. According to the Familial Importance Value, Moraceae, followed by Fabaceae, Lauraceae, and Sapotaceae, largely dominates this forest. Pseudolmedia oxyphillaria (Moraceae) is the dominant species (Importance Value Index), accounting for 25% of all the marked trees in the plots, followed by Clarisia racemosa (Moraceae), Heisteria concinna (Olacaceae), and Brosimum alicastrum (Moraceae). The size class distributions were similar among plots, and in general followed the expected J-inverted shape. Differences in tree abundance, floristic composition, and spatial distribution of some species among the plots suggest heterogeneity of this ecosystem's arborescent vegetation. Moreover, it is an important natural reservoir for the conservation of rare and endangered tree species in a national level. Using these results as a baseline, this study should start a long term monitoring of the structure and composition of this very reduced and fragmented ecosystem.

  16. Windmill structure

    SciTech Connect

    Yamada, M.

    1980-01-15

    A windmill structure is disclosed in which a combined structure of sails and electrical generator device is pivotally suspended so that the position of the combined structure may be shifted in accordance with the wind velocity.

  17. Cell Structure

    MedlinePlus

    ... Cells, Tissues, & Membranes Cell Structure & Function Cell Structure Cell Function Body Tissues Epithelial Tissue Connective Tissue Muscle Tissue ... apparatus , and lysosomes . « Previous (Cell Structure & Function) Next (Cell Function) » Contact Us | Privacy Policy | Accessibility | FOIA | File Formats ...

  18. On structures.

    PubMed

    Applegarth, A

    1989-01-01

    Some of the metapsychology involving the concept of structure is briefly reviewed, together with some difficulties presented by it. The concept of structure is defined, for purposes of the paper, and various kinds of structures are delineated. The author confines herself to the "microstructures," such as memories, cognitive structures, affect structures, defenses, identifications. Possible factors related to the development and maintenance of structures are discussed. In addition, the concept of structural change is taken up. It is suggested that an essential in such change is conscious review, however brief. The author proposes that structure formation and change is a fruitful area for mutual work by psychoanalysts and basic scientists.

  19. Structural screening by multiple reaction monitoring as a new approach for tandem mass spectrometry: presented for the determination of pyrrolizidine alkaloids in plants.

    PubMed

    These, Anja; Bodi, Dorina; Ronczka, Stefan; Lahrssen-Wiederholt, Monika; Preiss-Weigert, Angelika

    2013-11-01

    In tandem mass spectrometry the multiple reaction monitoring (MRM) mode is normally used for targeted analysis but this mode also has the potential to screen for structural similarities of analytes. On the basis of the fact that in general similar molecular structures result in similar fragments or losses of neutrals, this approach was used for pyrrolizidine alkaloid (PA) screening but could also be easily adapted to screen for other compound classes. PA are plant toxins of which several hundred individual compounds have been identified. Our MRM screening approach uses the structural relation and similar core structure of all PA which results in a common and thus predictable mass spectrometric fragmentation behaviour. On this basis a method was developed which screens for PA structures by MRM transitions and allows the detection of each individual PA down to a low microgram per kilogram concentration range. The approach was applied to investigate plants from the families of Asteraceae (several species of Senecio and Eupatorium), Boraginaceae (Echium, Cynoglossum, Borago and Anchusa officinalis as well as Heliotropium europaeum) and Fabaceae (Crotalaria incana) for a complete qualitative and quantitative PA characterisation. All analytes that were detected as possible PA by MRM screening were further investigated by recording product ion spectra. Analytes which exhibited a typical PA fragmentation pattern were either confirmed as PA or otherwise deleted as false positive signals (false positive rate was below 10 %). Sum formulas of confirmed PA were determined by additional measurements applying high resolution mass spectrometry. In that way 121 unknown PA were identified and for the first time complete PA profiles of different PA plants were delivered. PMID:24114465

  20. Website Structure

    ERIC Educational Resources Information Center

    Jackson, Larry S.

    2009-01-01

    This dissertation reports the results of an exploratory data analysis investigation of the relationship between the structures used for information organization and access and the associated storage structures within state government websites. Extending an earlier claim that hierarchical directory structures are both the preeminent information…

  1. Phytotoxic cyanamide affects maize (Zea mays) root growth and root tip function: from structure to gene expression.

    PubMed

    Soltys, Dorota; Rudzińska-Langwald, Anna; Kurek, Wojciech; Szajko, Katarzyna; Sliwinska, Elwira; Bogatek, Renata; Gniazdowska, Agnieszka

    2014-05-01

    Cyanamide (CA) is a phytotoxic compound produced by four Fabaceae species: hairy vetch, bird vetch, purple vetch and black locust. Its toxicity is due to complex activity that involves the modification of both cellular structures and physiological processes. To date, CA has been investigated mainly in dicot plants. The goal of this study was to investigate the effects of CA in the restriction of the root growth of maize (Zea mays), representing the monocot species. CA (3mM) reduced the number of border cells in the root tips of maize seedlings and degraded their protoplasts. However, CA did not induce any significant changes in the organelle structure of other root cells, apart from increased vacuolization. CA toxicity was also demonstrated by its effect on cell cycle activity, endoreduplication intensity, and modifications of cyclins CycA2, CycD2, and histone HisH3 gene expression. In contrast, the arrangement of microtubules was not altered by CA. Treatment of maize seedlings with CA did not completely arrest mitotic activity, although the frequency of dividing cells was reduced. Furthermore, prolonged CA treatment increased the proportion of endopolyploid cells in the root tip. Cytological malformations were accompanied by an induction of oxidative stress in root cells, which manifested as enhanced accumulation of H2O2. Exposure of maize seedlings to CA resulted in an increased concentration of auxin and stimulated ethylene emission. Taken together, these findings suggested that the inhibition of root growth by CA may be a consequence of stress-induced morphogenic responses.

  2. Phytotoxic cyanamide affects maize (Zea mays) root growth and root tip function: from structure to gene expression.

    PubMed

    Soltys, Dorota; Rudzińska-Langwald, Anna; Kurek, Wojciech; Szajko, Katarzyna; Sliwinska, Elwira; Bogatek, Renata; Gniazdowska, Agnieszka

    2014-05-01

    Cyanamide (CA) is a phytotoxic compound produced by four Fabaceae species: hairy vetch, bird vetch, purple vetch and black locust. Its toxicity is due to complex activity that involves the modification of both cellular structures and physiological processes. To date, CA has been investigated mainly in dicot plants. The goal of this study was to investigate the effects of CA in the restriction of the root growth of maize (Zea mays), representing the monocot species. CA (3mM) reduced the number of border cells in the root tips of maize seedlings and degraded their protoplasts. However, CA did not induce any significant changes in the organelle structure of other root cells, apart from increased vacuolization. CA toxicity was also demonstrated by its effect on cell cycle activity, endoreduplication intensity, and modifications of cyclins CycA2, CycD2, and histone HisH3 gene expression. In contrast, the arrangement of microtubules was not altered by CA. Treatment of maize seedlings with CA did not completely arrest mitotic activity, although the frequency of dividing cells was reduced. Furthermore, prolonged CA treatment increased the proportion of endopolyploid cells in the root tip. Cytological malformations were accompanied by an induction of oxidative stress in root cells, which manifested as enhanced accumulation of H2O2. Exposure of maize seedlings to CA resulted in an increased concentration of auxin and stimulated ethylene emission. Taken together, these findings suggested that the inhibition of root growth by CA may be a consequence of stress-induced morphogenic responses. PMID:24709147

  3. Aeropropulsion structures

    NASA Technical Reports Server (NTRS)

    Nichols, Lester D.

    1987-01-01

    The structural engineer is faced with unique problems when dealing with aeropropulsion systems. He is faced with extremes in operating temperatures, rotational effects, and behaviors of advanced material systems which combine into complexities that require advances in many scientific disciplines involved in structural analysis and design procedures. This presentation provides an overview of the complexities of aeropropulsion structures and the theoretical, computational, and experimental research conducted to achieve the needed advances.

  4. Structural Ceramics

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This publication is a compilation of abstracts and slides of papers presented at the NASA Lewis Structural Ceramics Workshop. Collectively, these papers depict the scope of NASA Lewis' structural ceramics program. The technical areas include monolithic SiC and Si3N4 development, ceramic matrix composites, tribology, design methodology, nondestructive evaluation (NDE), fracture mechanics, and corrosion.

  5. Organisational Structure

    ERIC Educational Resources Information Center

    National Centre for Vocational Education Research (NCVER), 2006

    2006-01-01

    An understanding of organisational structure can provide guidance for organisations that want to change and innovate. Many writers agree that this understanding allows organisations to shape how their work is done to ultimately achieve their business goals--and that too often structure is given little consideration in business strategy and…

  6. Protein Structure

    ERIC Educational Resources Information Center

    Asmus, Elaine Garbarino

    2007-01-01

    Individual students model specific amino acids and then, through dehydration synthesis, a class of students models a protein. The students clearly learn amino acid structure, primary, secondary, tertiary, and quaternary structure in proteins and the nature of the bonds maintaining a protein's shape. This activity is fun, concrete, inexpensive and…

  7. Curriculum Structure and Faculty Structure.

    ERIC Educational Resources Information Center

    Hazard, Geoffrey C., Jr.

    1985-01-01

    The structure of the law school curriculum is a product of the structure of the law school faculty, which may explain why the law school curriculum neither has changed very much over the years, despite repeated calls for reform, nor will change much in the future. (MSE)

  8. Spacecraft Structures

    NASA Video Gallery

    This activity challenges students to solve a real-world problem that is part of the space program using creativity, cleverness and scientific knowledge while learning about forces, structures and e...

  9. Nuclear Structure

    NASA Astrophysics Data System (ADS)

    Gargano, Angela

    2003-04-01

    An account of recent studies in the field of theoretical nuclear structure is reported. These studies concern essentially research activities performed under the Italian project "Fisica Teorica del Nucleo e dei Sistemi a Molti Corpi". Special attention is addressed to results obtained during the last two years as regards the development of new many-body techniques as well as the interpretation of new experimental aspects of nuclear structure.

  10. Structural Analysis

    NASA Technical Reports Server (NTRS)

    1991-01-01

    After an 800-foot-tall offshore oil recovery platform collapsed, the engineers at Engineering Dynamics, Inc., Kenner, LA, needed to learn the cause of the collapse, and analyze the proposed repairs. They used STAGSC-1, a NASA structural analysis program with geometric and nonlinear buckling analysis. The program allowed engineers to determine the deflected and buckling shapes of the structural elements. They could then view the proposed repairs under the pressure that caused the original collapse.

  11. Structures research

    NASA Technical Reports Server (NTRS)

    Abu-Saba, Elias; Mcginley, Williams; Shen, Ji-Yao

    1992-01-01

    The main objective of the structures group is to provide quality aerospace research with the Center for Aerospace Research - A NASA Center for Excellence at North Carolina Agricultural and Technical State University. The group includes dedicated faculty and students who have a proven record in the area of structures, in particular space structures. The participating faculty developed accurate mathematical models and effective computational algorithms to characterize the flexibility parameters of joint dominated beam-truss structures. Both experimental and theoretical modelling has been applied to the dynamic mode shapes and mode frequencies for a large truss system. During the past few months, the above procedures has been applied to the hypersonic transport plane model. The plane structure has been modeled as a lumped mass system by Doctor Abu-Saba while Doctor Shen applied the transfer matrix method with a piecewise continuous Timoshenko tapered beam model. Results from both procedures compare favorably with those obtained using the finite element method. These two methods are more compact and require less computer time than the finite element method. The group intends to perform experiments on structural systems including the hypersonic plane model to verify the results from the theoretical models.

  12. Structures Division

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The NASA Lewis Research Center Structures Division is an international leader and pioneer in developing new structural analysis, life prediction, and failure analysis related to rotating machinery and more specifically to hot section components in air-breathing aircraft engines and spacecraft propulsion systems. The research consists of both deterministic and probabilistic methodology. Studies include, but are not limited to, high-cycle and low-cycle fatigue as well as material creep. Studies of structural failure are at both the micro- and macrolevels. Nondestructive evaluation methods related to structural reliability are developed, applied, and evaluated. Materials from which structural components are made, studied, and tested are monolithics and metal-matrix, polymer-matrix, and ceramic-matrix composites. Aeroelastic models are developed and used to determine the cyclic loading and life of fan and turbine blades. Life models are developed and tested for bearings, seals, and other mechanical components, such as magnetic suspensions. Results of these studies are published in NASA technical papers and reference publication as well as in technical society journal articles. The results of the work of the Structures Division and the bibliography of its publications for calendar year 1995 are presented.

  13. Centriole structure.

    PubMed

    Winey, Mark; O'Toole, Eileen

    2014-09-01

    Centrioles are among the largest protein-based structures found in most cell types, measuring approximately 250 nm in diameter and approximately 500 nm long in vertebrate cells. Here, we briefly review ultrastructural observations about centrioles and associated structures. At the core of most centrioles is a microtubule scaffold formed from a radial array of nine triplet microtubules. Beyond the microtubule triplets of the centriole, we discuss the critically important cartwheel structure and the more enigmatic luminal density, both found on the inside of the centriole. Finally, we discuss the connectors between centrioles, and the distal and subdistal appendages outside of the microtubule scaffold that reflect centriole age and impart special functions to the centriole. Most of the work we review has been done with electron microscopy or electron tomography of resin-embedded samples, but we also highlight recent work performed with cryoelectron microscopy, cryotomography and subvolume averaging. Significant opportunities remain in the description of centriolar structure, both in mapping of component proteins within the structure and in determining the effect of mutations on components that contribute to the structure and function of the centriole.

  14. Structural biology.

    PubMed Central

    Holmes, K C

    1999-01-01

    Protein crystallography has become a major technique for understanding cellular processes. This has come about through great advances in the technology of data collection and interpretation, particularly the use of synchrotron radiation. The ability to express eukaryotic genes in Escherichia coli is also important. Analysis of known structures shows that all proteins are built from about 1000 primeval folds. The collection of all primeval folds provides a basis for predicting structure from sequence. At present about 450 are known. Of the presently sequenced genomes only a fraction can be related to known proteins on the basis of sequence alone. Attempts are being made to determine all (or as many as possible) of the structures from some bacterial genomes in the expectation that structure will point to function more reliably than does sequence. Membrane proteins present a special problem. The next 20 years may see the experimental determination of another 40,000 protein structures. This will make considerable demands on synchrotron sources and will require many more biochemists than are currently available. The availability of massive structure databases will alter the way biochemistry is done. PMID:10670018

  15. Composite structural materials. [aircraft structures

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Loewy, R. G.; Wiberley, S. E.

    1980-01-01

    The use of filamentary composite materials in the design and construction of primary aircraft structures is considered with emphasis on efforts to develop advanced technology in the areas of physical properties, structural concepts and analysis, manufacturing, and reliability and life prediction. The redesign of a main spar/rib region on the Boeing 727 elevator near its actuator attachment point is discussed. A composite fabrication and test facility is described as well as the use of minicomputers for computer aided design. Other topics covered include (1) advanced structural analysis methids for composites; (2) ultrasonic nondestructive testing of composite structures; (3) optimum combination of hardeners in the cure of epoxy; (4) fatigue in composite materials; (5) resin matrix characterization and properties; (6) postbuckling analysis of curved laminate composite panels; and (7) acoustic emission testing of composite tensile specimens.

  16. Tension Structure

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The fabric structure pictured is the Campus Center of La Verne College, La Verne, California. Unlike the facilities shown on the preceding pages, it is not air-supported. It is a "tension structure," its multi-coned fabric membrane supported by a network of cables attached to steel columns which function like circus tent poles. The spider-web in the accompanying photo is a computer graph of the tension pattern. The designers, Geiger-Berger Associates PC, of New York City, conducted lengthy computer analysis to determine the the best placement of columns and cables. The firm also served as structural engineering consultant on the Pontiac Silverdome and a number of other large fabric structures. Built by Birdair Structures, Inc., Buffalo, New York, the La Verne Campus Center was the first permanent facility in the United States enclosed by the space-spinoff fabric made of Owens-Corning Beta fiber glass coated with Du Pont Teflon TFE. The flexible design permits rearrangement of the interior to accommodate athletic events, student activities, theatrical productions and other recreational programs. Use of fabric covering reduced building cost 30 percent below conventional construction.

  17. Microcavity structures

    SciTech Connect

    Kustom, R.L.; Grudzien, D.; Feinerman, A.D.

    1994-10-01

    The feasibility of building mm-wave cavities using deep x-ray lithography techniques is being investigated. These cavities could be considered for linac accelerating structures, undulators, free electron lasers, or mm-wave amplifiers. The construction process includes making precision x-ray masks, x-ray exposure of poly-methyl-methacrylate (PMMA), removal of PMMA, and electroplating a metal. Highly precise two-dimensional features can be machined onto wafers by this technique. The challenge is to fabricate the wafers onto three-dimensional rf structures. Rectangular cavity geometry is best suited to this fabrication technique. Status of wafer manufacture, fabrication and alignment techniques using capillaries bonded in precision grooves, 2{pi}/3 120-GHz linac structures, heat extraction analysis, and beam dynamics in a 5-meter-long 50-MeV linac will be discussed. Measurements made on 10X larger scale models that were built with conventional techniques will also be discussed.

  18. Structural Diagnosis

    NASA Technical Reports Server (NTRS)

    1987-01-01

    All over the world, officials charged with preserving historical structures are faced with a problem of environmental contamination of building materials that cause structural deterioration. First requisite for preserving the structure is identification of the nature of contaminants. A "non-invasive"technique based on space technology has been developed and tested. It employs a neutron source and a gamma ray detector. Placed on one side of the wall to be examined, the source fires neutrons created by the decay of a radioactive isotope. As they pass through the wall, the neutrons collide with atoms and the atoms, depending on their type, emit various kinds of gamma rays. These rays are identified by the gamma ray detector on the other side of the wall. Energy of the rays shows the kind of element present. The intensity level indicates the quantity. Composition of the contaminants within the walls is determined by a multichannel analyzer.

  19. Structure of

    PubMed

    Mahmoudkhani; Langer

    1999-10-01

    The crystal structure of the title compound, dimethylammonium tetrachlorocobaltate(II), has been determined at four temperatures between 297 and 366 K, in order to investigate possible phase transitions at 313 and 353 K [Kapustianik, Polovinko & Kaluza et al. (1996). Phys. Status Solidi A, 153, 117-122]. We found that there is no significant change either in the hydrogen-bonding network or in the cell parameters, apart from a linear dilatation with temperature. This study reveals that the anomalous variation in electric conductivity and some of the other physical properties of the compound cannot be explained by structural changes.

  20. Structural evolution

    SciTech Connect

    Burr, M.T.

    1993-03-01

    In this special report, financial executives discuss key trends in power project finance, new funding sources and evolving project structures. Industry wide, financial firms and developers are striving to improve the cost-effectiveness and efficiency of project financing, for projects in both greenfield development and the growing secondary market.

  1. Nanocrystal structures

    DOEpatents

    Eisler, Hans J.; Sundar, Vikram C.; Walsh, Michael E.; Klimov, Victor I.; Bawendi, Moungi G.; Smith, Henry I.

    2006-12-19

    A structure including a grating and a semiconductor nanocrystal layer on the grating, can be a laser. The semiconductor nanocrystal layer can include a plurality of semiconductor nanocrystals including a Group II–VI compound, the nanocrystals being distributed in a metal oxide matrix. The grating can have a periodicity from 200 nm to 500 nm.

  2. Structural Adaptation

    ERIC Educational Resources Information Center

    Crowley, Julianne; Titmus, Morgan

    2016-01-01

    This article explores an alternative conception held by high school and first-year university biology students regarding the structure of the left and right ventricles of the heart and the significance of the left ventricular wall being thicker than the right. The left ventricular wall of the heart is thicker than the right ventricular wall due to…

  3. Nanocrystal structures

    SciTech Connect

    Eisler, Hans J.; Sundar, Vikram C.; Walsh, Michael E.; Klimov, Victor I.; Bawendi, Moungi G.; Smith, Henry I.

    2008-12-30

    A structure including a grating and a semiconductor nanocrystal layer on the grating, can be a laser. The semiconductor nanocrystal layer can include a plurality of semiconductor nanocrystals including a Group II-VI compound, the nanocrystals being distributed in a metal oxide matrix. The grating can have a periodicity from 200 nm to 500 nm.

  4. Terminal structure

    DOEpatents

    Schmidt, Frank; Allais, Arnaud; Mirebeau, Pierre; Ganhungu, Francois; Lallouet, Nicolas

    2009-10-20

    A terminal structure (2) for a superconducting cable (1) is described. It consists of a conductor (2a) and an insulator (2b) that surrounds the conductor (2a), wherein the superconducting cable (1) has a core with a superconducting conductor (5) and a layer of insulation that surrounds the conductor (5), and wherein the core is arranged in such a way that it can move longitudinally in a cryostat. The conductor (2a) of the terminal structure (2) is electrically connected with the superconducting conductor (5) or with a normal conductor (6) that is connected with the superconducting conductor (5) by means of a tubular part (7) made of an electrically conductive material, wherein the superconducting conductor (5) or the normal conductor (6) can slide in the part (7) in the direction of the superconductor.

  5. Superconducting Structure

    DOEpatents

    Kwon, Chuhee; Jia, Quanxi; Foltyn, Stephen R.

    2005-09-13

    A superconductive structure including a dielectric oxide substrate, a thin buffer layer of a superconducting material thereon; and, a layer of a rare earth-barium-copper oxide superconducting film thereon the thin layer of yttrium-barium-copper oxide, the rare earth selected from the group consisting of samarium, gadolinium, ytterbium, erbium, neodymium, dysprosium, holmium, lutetium, a combination of more than one element from the rare earth group and a combination of one or more elements from the rare earth group with yttrium, the buffer layer of superconducting material characterized as having chemical and structural compatibility with the dielectric oxide substrate and the rare earth-barium-copper oxide superconducting film is provided.

  6. Superconducting structure

    DOEpatents

    Kwon, Chuhee; Jia, Quanxi; Foltyn, Stephen R.

    2003-04-01

    A superconductive structure including a dielectric oxide substrate, a thin buffer layer of a superconducting material thereon; and, a layer of a rare earth-barium-copper oxide superconducting film thereon the thin layer of yttrium-barium-copper oxide, the rare earth selected from the group consisting of samarium, gadolinium, ytterbium, erbium, neodymium, dysprosium, holmium, lutetium, a combination of more than one element from the rare earth group and a combination of one or more elements from the rare earth group with yttrium, the buffer layer of superconducting material characterized as having chemical and structural compatibility with the dielectric oxide substrate and the rare earth-barium-copper oxide superconducting film is provided.

  7. Tamarindus indica: Extent of explored potential.

    PubMed

    Bhadoriya, Santosh Singh; Ganeshpurkar, Aditya; Narwaria, Jitendra; Rai, Gopal; Jain, Alok Pal

    2011-01-01

    Tamarindus is a monotypic genus and belongs to the subfamily Caesalpinioideae of the family Leguminosae (Fabaceae), Tamarindus indica L., commonly known as Tamarind tree is one of the most important multipurpose tropical fruit tree species in the Indian subcontinent. Tamarind fruit was at first thought to be produced by an Indian palm, as the name Tamarind comes from a Persian word "Tamar-I-hind," meaning date of India. Its name "Amlika" in Sanskrit indicates its ancient presence in the country. T.indica is used as traditional medicine in India, Africa, Pakistan, Bangladesh, Nigeria,and most of the tropical countries. It is used traditionally in abdominal pain, diarrhea and dysentery, helminthes infections, wound healing, malaria and fever, constipation, inflammation, cell cytotoxicity, gonorrhea, and eye diseases. It has numerous chemical values and is rich in phytochemicals, and hence the plant is reported to possess antidiabetic activity, antimicrobial activity, antivenomic activity, antioxidant activity, antimalarial activity, hepatoprotective activity, antiasthmatic activity, laxative activity, and anti-hyperlipidemic activity. Every part of the plant from root to leaf tips is useful for human needs. Thus the aim of the present review is to describe its morphology, and explore the phytochemical constituents, commercial utilization of the parts of the plant, and medicinal and pharmacologic activities so that T. indica's potential as multipurpose tree species can be understood.

  8. Tamarindus indica: Extent of explored potential

    PubMed Central

    Bhadoriya, Santosh Singh; Ganeshpurkar, Aditya; Narwaria, Jitendra; Rai, Gopal; Jain, Alok Pal

    2011-01-01

    Tamarindus is a monotypic genus and belongs to the subfamily Caesalpinioideae of the family Leguminosae (Fabaceae), Tamarindus indica L., commonly known as Tamarind tree is one of the most important multipurpose tropical fruit tree species in the Indian subcontinent. Tamarind fruit was at first thought to be produced by an Indian palm, as the name Tamarind comes from a Persian word “Tamar-I-hind,” meaning date of India. Its name “Amlika” in Sanskrit indicates its ancient presence in the country. T.indica is used as traditional medicine in India, Africa, Pakistan, Bangladesh, Nigeria,and most of the tropical countries. It is used traditionally in abdominal pain, diarrhea and dysentery, helminthes infections, wound healing, malaria and fever, constipation, inflammation, cell cytotoxicity, gonorrhea, and eye diseases. It has numerous chemical values and is rich in phytochemicals, and hence the plant is reported to possess antidiabetic activity, antimicrobial activity, antivenomic activity, antioxidant activity, antimalarial activity, hepatoprotective activity, antiasthmatic activity, laxative activity, and anti-hyperlipidemic activity. Every part of the plant from root to leaf tips is useful for human needs. Thus the aim of the present review is to describe its morphology, and explore the phytochemical constituents, commercial utilization of the parts of the plant, and medicinal and pharmacologic activities so that T. indica's potential as multipurpose tree species can be understood. PMID:22096321

  9. Sarcodon in the Neotropics I: new species from Guyana, Puerto Rico and Belize.

    PubMed

    Grupe, Arthur C; Baker, Anthony D; Uehling, Jessie K; Smith, Matthew E; Baroni, Timothy J; Lodge, D Jean; Henkel, Terry W

    2015-01-01

    Four species of the ectomycorrhizal (ECM) genus Sarcodon (Bankeraceae, Thelephorales, Basidiomycota) are described as new to science. Sarcodon pakaraimensis sp. nov. is described from forests dominated by the ECM trees Pakaraimaea dipterocarpacea (Dipterocarpaceae) and Dicymbe jenmanii (Fabaceae subfam. Caesalpinioideae) in the Pakaraima Mountains of Guyana. Sarcodon portoricensis sp. nov. is described from lower montane wet forest within the El Yunque National Forest of Puerto Rico. Sarcodon quercophilus sp. nov. and Sarcodon umbilicatus sp. nov. are described from Quercus (Fagaceae) cloud forests within the Maya Mountains of Belize. The discovery of these species is significant given that the majority of the approximately 87 described Sarcodon species are north temperate or boreal in distribution and frequently associate with coniferous host plants; these constitute the most recent records for Sarcodon from the greater Neotropics. Each of the new species is morphologically consistent with accepted diagnostic characters for Sarcodon: pileate-stipitate stature, a dentate hymenophore, determinate basidiomatal development, fleshy, non-zonate context and brown, tuberculate basidiospores. DNA (ITS) sequence analysis corroborated the generic placement of S. pakaraimensis, S. portoricensis, S. quercophilus and S. umbilicatus and, along with morphological differences, supported their recognition as distinct species. Macromorphological, micromorphological, habitat and DNA sequence data from the nuc rDNA internal transcribed spacer region (ITS) are provided for each of the new species. A key to Neotropical Sarcodon species and similar extralimital taxa is provided. PMID:25661714

  10. Cantharellaceae of Guyana II: new species of Craterellus, new South American distribution records for Cantharellus guyanensis and Craterellus excelsus, and a key to the Neotropical taxa.

    PubMed

    Henkel, Terry W; Wilson, Andrew W; Aime, M Catherine; Dierks, Janina; Uehling, Jessie K; Roy, Melanie; Schimann, Heidy; Wartchow, Felipe; Mueller, Gregory M

    2014-01-01

    Craterellus olivaceoluteus sp. nov. and Craterellus cinereofimbriatus sp. nov. are described as new to science. These fungi were collected from Guyana in association with ectomycorrhizal host trees in the genera Dicymbe (Fabaceae subfam. Caesalpinioideae) and Pakaraimaea (Dipterocarpaceae). Cantharellus guyanensis Mont., originally described from French Guiana, is redescribed from recent collections from Guyana, with additional range extensions for the species provided based on material examined from French Guiana, Venezuela, and north central, northeastern and southern Brazil, circumscribing nearly the entire Guiana Shield region and beyond. A new distribution record from French Guiana is provided for Craterellus excelsus T.W. Henkel & Aime. Macromorphological, micromorphological and habitat data are provided for the new species and C. guyanensis as well as DNA sequence data from the nuclear ribosomal regions of the internal transcribed spacer (ITS) and 28S large subunit (LSU); additional sequence data is provided for C. guyanensis and C. excelsus specimens collected outside Guyana. The relationships of these taxa within the Cantharellaceae were evaluated with phylogenetic analyses of ITS and LSU sequence data. This work brings the total number of Cantharellaceae species known from Guyana to eight. A key to the Cantharellus and Craterellus species known from the lowland Neotropics and extralimital montane Central and South America is provided.

  11. Tamarindus indica: Extent of explored potential.

    PubMed

    Bhadoriya, Santosh Singh; Ganeshpurkar, Aditya; Narwaria, Jitendra; Rai, Gopal; Jain, Alok Pal

    2011-01-01

    Tamarindus is a monotypic genus and belongs to the subfamily Caesalpinioideae of the family Leguminosae (Fabaceae), Tamarindus indica L., commonly known as Tamarind tree is one of the most important multipurpose tropical fruit tree species in the Indian subcontinent. Tamarind fruit was at first thought to be produced by an Indian palm, as the name Tamarind comes from a Persian word "Tamar-I-hind," meaning date of India. Its name "Amlika" in Sanskrit indicates its ancient presence in the country. T.indica is used as traditional medicine in India, Africa, Pakistan, Bangladesh, Nigeria,and most of the tropical countries. It is used traditionally in abdominal pain, diarrhea and dysentery, helminthes infections, wound healing, malaria and fever, constipation, inflammation, cell cytotoxicity, gonorrhea, and eye diseases. It has numerous chemical values and is rich in phytochemicals, and hence the plant is reported to possess antidiabetic activity, antimicrobial activity, antivenomic activity, antioxidant activity, antimalarial activity, hepatoprotective activity, antiasthmatic activity, laxative activity, and anti-hyperlipidemic activity. Every part of the plant from root to leaf tips is useful for human needs. Thus the aim of the present review is to describe its morphology, and explore the phytochemical constituents, commercial utilization of the parts of the plant, and medicinal and pharmacologic activities so that T. indica's potential as multipurpose tree species can be understood. PMID:22096321

  12. Ecological Importance of Small-Diameter Trees to the Structure, Diversity and Biomass of a Tropical Evergreen Forest at Rabi, Gabon.

    PubMed

    Memiaghe, Hervé R; Lutz, James A; Korte, Lisa; Alonso, Alfonso; Kenfack, David

    2016-01-01

    Tropical forests have long been recognized for their biodiversity and ecosystem services. Despite their importance, tropical forests, and particularly those of central Africa, remain understudied. Until recently, most forest inventories in Central Africa have focused on trees ≥10 cm in diameter, even though several studies have shown that small-diameter tree population may be important to demographic rates and nutrient cycling. To determine the ecological importance of small-diameter trees in central African forests, we used data from a 25-ha permanent plot that we established in the rainforest of Gabon to study the diversity and dynamics of these forests. Within the plot, we censused 175,830 trees ≥1 cm dbh from 54 families, 192 genera, and 345 species. Average tree density was 7,026 trees/ha, basal area 31.64 m2/ha, and above-ground biomass 369.40 Mg/ha. Fabaceae, Ebenaceae and Euphorbiaceae were the most important families by basal area, density and above-ground biomass. Small-diameter trees (1 cm ≥ dbh <10 cm) comprised 93.7% of the total tree population, 16.5% of basal area, and 4.8% of the above-ground biomass. They also had diversity 18% higher at family level, 34% higher at genus level, and 42% higher at species level than trees ≥10 cm dbh. Although the relative contribution of small-diameter trees to biomass was comparable to other forests globally, their contribution to forest density, and diversity was disproportionately higher. The high levels of diversity within small-diameter classes may give these forests high levels of structural resilience to anthropogenic/natural disturbance and a changing climate. PMID:27186658

  13. Ecological Importance of Small-Diameter Trees to the Structure, Diversity and Biomass of a Tropical Evergreen Forest at Rabi, Gabon

    PubMed Central

    Memiaghe, Hervé R.; Lutz, James A.; Korte, Lisa; Alonso, Alfonso; Kenfack, David

    2016-01-01

    Tropical forests have long been recognized for their biodiversity and ecosystem services. Despite their importance, tropical forests, and particularly those of central Africa, remain understudied. Until recently, most forest inventories in Central Africa have focused on trees ≥10 cm in diameter, even though several studies have shown that small-diameter tree population may be important to demographic rates and nutrient cycling. To determine the ecological importance of small-diameter trees in central African forests, we used data from a 25-ha permanent plot that we established in the rainforest of Gabon to study the diversity and dynamics of these forests. Within the plot, we censused 175,830 trees ≥1 cm dbh from 54 families, 192 genera, and 345 species. Average tree density was 7,026 trees/ha, basal area 31.64 m2/ha, and above-ground biomass 369.40 Mg/ha. Fabaceae, Ebenaceae and Euphorbiaceae were the most important families by basal area, density and above-ground biomass. Small-diameter trees (1 cm ≥ dbh <10 cm) comprised 93.7% of the total tree population, 16.5% of basal area, and 4.8% of the above-ground biomass. They also had diversity 18% higher at family level, 34% higher at genus level, and 42% higher at species level than trees ≥10 cm dbh. Although the relative contribution of small-diameter trees to biomass was comparable to other forests globally, their contribution to forest density, and diversity was disproportionately higher. The high levels of diversity within small-diameter classes may give these forests high levels of structural resilience to anthropogenic/natural disturbance and a changing climate. PMID:27186658

  14. Ecological Importance of Small-Diameter Trees to the Structure, Diversity and Biomass of a Tropical Evergreen Forest at Rabi, Gabon.

    PubMed

    Memiaghe, Hervé R; Lutz, James A; Korte, Lisa; Alonso, Alfonso; Kenfack, David

    2016-01-01

    Tropical forests have long been recognized for their biodiversity and ecosystem services. Despite their importance, tropical forests, and particularly those of central Africa, remain understudied. Until recently, most forest inventories in Central Africa have focused on trees ≥10 cm in diameter, even though several studies have shown that small-diameter tree population may be important to demographic rates and nutrient cycling. To determine the ecological importance of small-diameter trees in central African forests, we used data from a 25-ha permanent plot that we established in the rainforest of Gabon to study the diversity and dynamics of these forests. Within the plot, we censused 175,830 trees ≥1 cm dbh from 54 families, 192 genera, and 345 species. Average tree density was 7,026 trees/ha, basal area 31.64 m2/ha, and above-ground biomass 369.40 Mg/ha. Fabaceae, Ebenaceae and Euphorbiaceae were the most important families by basal area, density and above-ground biomass. Small-diameter trees (1 cm ≥ dbh <10 cm) comprised 93.7% of the total tree population, 16.5% of basal area, and 4.8% of the above-ground biomass. They also had diversity 18% higher at family level, 34% higher at genus level, and 42% higher at species level than trees ≥10 cm dbh. Although the relative contribution of small-diameter trees to biomass was comparable to other forests globally, their contribution to forest density, and diversity was disproportionately higher. The high levels of diversity within small-diameter classes may give these forests high levels of structural resilience to anthropogenic/natural disturbance and a changing climate.

  15. Leaves and fruits of Bauhinia (Leguminosae, Caesalpinioideae, Cercideae) from the Oligocene Ningming Formation of Guangxi, South China and their biogeographic implications

    PubMed Central

    2014-01-01

    Background The pantropical genus Bauhinia, along with the northern temperate Cercis and several tropical genera, bear bilobate, bifoliolate, or sometimes unifoliolate leaves, which constitute the tribe Cercideae as sister to the rest of the family Leguminosae based on molecular phylogenetics. Hence, the fossil record of Cercideae is pivotal to understand the early evolution and biogeographic history of legumes. Results Three fossil species of Bauhinia were described from the Oligocene Ningming Formation of Guangxi, South China. Bauhinia ningmingensis sp. nov. is characterized by its bifoliolate, pulvinate leaves bearing basal acrodromous primary veins and brochidodromous secondary veins. B. cheniae sp. nov. bears moderately or deeply bilobate, pulvinate leaves, with basal actinodromous primary veins and eucamptodromous secondary veins. B. larsenii D.X. Zhang et Y.F. Chen emend. possesses shallowly or moderately bilobate, pulvinate leaves bearing basal actinodromous primary veins and brochidodromous secondary veins, as well as elliptic, stipitate, non-winged, and oligo-seeded fruits. Meanwhile, previously reported Bauhinia fossils were reviewed, and those pre-Oligocene foliage across the world are either questionable or have been rejected due to lacking of reliable evidence for their pulvini or/and basal actinodromous or acrodromous venations. Besides Oligocene leaves and fruits presented here, foliage and/or wood of Bauhinia have been documented from the Miocene–Pliocene of Thailand, India, Nepal, Uganda, and Ecuador. Conclusions Bauhinia has exhibited a certain diversity with bifoliolate- and bilobate-leafed species in a low-latitude locality–Ningming since at least the Oligocene, implying that the tropical zone of South China may represent one of the centres for early diversification of the genus. The reliable macrofossils of Bauhinia and Cercis have made their debut in the Eocene–Oligocene floras from mid-low latitudes and appeared to lack in the coeval floras at high latitudes, implying a possible Tethys Seaway origin and spread of legumes. However, detailed scenarios for the historical biogeography of Bauhinia and its relatives still need more robust dataset from palaeobotany and molecular phylogeny in future research. PMID:24758153

  16. Airfoil structure

    SciTech Connect

    Frey, Gary A.; Twardochleb, Christopher Z.

    1998-01-01

    Past airfoil configurations have been used to improve aerodynamic performance and engine efficiencies. The present airfoil configuration further increases component life and reduces maintenance by reducing internal stress within the airfoil itself. The airfoil includes a chord and a span. Each of the chord and the span has a bow being summed to form a generally "C" configuration of the airfoil. The generally "C" configuration includes a compound bow in which internal stresses resulting from a thermal temperature gradient are reduced. The structural configuration reduces internal stresses resulting from thermal expansion.

  17. Airfoil structure

    DOEpatents

    Frey, G.A.; Twardochleb, C.Z.

    1998-01-13

    Past airfoil configurations have been used to improve aerodynamic performance and engine efficiencies. The present airfoil configuration further increases component life and reduces maintenance by reducing internal stress within the airfoil itself. The airfoil includes a chord and a span. Each of the chord and the span has a bow being summed to form a generally ``C`` configuration of the airfoil. The generally ``C`` configuration includes a compound bow in which internal stresses resulting from a thermal temperature gradient are reduced. The structural configuration reduces internal stresses resulting from thermal expansion. 6 figs.

  18. Armor structures

    DOEpatents

    Chu, Henry Shiu-Hung [Idaho Falls, ID; Lacy, Jeffrey M [Idaho Falls, ID

    2008-04-01

    An armor structure includes first and second layers individually containing a plurality of i-beams. Individual i-beams have a pair of longitudinal flanges interconnected by a longitudinal crosspiece and defining opposing longitudinal channels between the pair of flanges. The i-beams within individual of the first and second layers run parallel. The laterally outermost faces of the flanges of adjacent i-beams face one another. One of the longitudinal channels in each of the first and second layers faces one of the longitudinal channels in the other of the first and second layers. The channels of the first layer run parallel with the channels of the second layer. The flanges of the first and second layers overlap with the crosspieces of the other of the first and second layers, and portions of said flanges are received within the facing channels of the i-beams of the other of the first and second layers.

  19. Digital structural

    USGS Publications Warehouse

    Dohm, J.M.; Anderson, R.C.; Tanaka, K.L.

    1998-01-01

    Magmatic and tectonic activity have both contributed significantly to the surface geology of Mars. Digital structural mapping techniques have now been used to classify and date centers of tectonic activity in the western equatorial region. For example, our results show a center of tectonic activity at Valles Marineris, which may be associated with uplift caused by intrusion. Such evidence may help explain, in part, the development of the large troughs and associated outflow channels and chaotic terrain. We also find a local centre of tectonic activity near the source region of Warrego Valles. Here, we suggest that the valley system may have resulted largely from intrusive-related hydrothermal activity. We hope that this work, together with the current Mars Global Surveyor mission, will lead to a better understanding of the geological processes that shaped the Martian surface.

  20. Asteroid structure

    NASA Astrophysics Data System (ADS)

    Asphaug, E.

    2014-07-01

    Even before the first space missions to asteroids, in the mid-1990s, it was known that asteroids have weird structures. Photometry indicated complicated shapes, and the pioneering radar investigations by Ostro and colleagues followed by adaptive optics campaigns and flybys showed odd binary forms, and confirmed the common presence of satellites, and indications of highly varying surface roughness. Some asteroids turned out to be dominated by a single major cratering event, while others showed no evidence of a major crater, or perhaps for global crater erasure. The first space mission to orbit an asteroid, NEAR, found a mixture of heavily cratered terrains and geomorphically active 'ponds', and indicated evidence for global seismicity from impact. The next mission to orbit an asteroid, Hayabusa, found what most agree is a rubble pile, with no major craters and an absence of fines. There is to date no direct evidence of asteroid interior geology, other than measurements of bulk density, and inferences made for mass distribution asymmetry based on dynamics, and inferences based on surface lineaments. Interpolating from the surface to the interior is always risky and usually wrong, but of course the answer is important since we are someday destined to require this knowledge in order to divert a hazardous asteroid from impact with the Earth. Even considering the near-subsurface, here we remain as ignorant as we were about the Moon in the early 1960s, whether the surface will swallow us up in dust, or will provide secure landing and anchoring points. Laboratory experimentation in close to zero-G is still in its early stages. Adventures such as mining and colonization will surely have to wait until we better know these things. How do we get from here to there? I will focus on 3 areas of progress: (1) asteroid cratering seismology, where we use the surface craters to understand what is going on inside; (2) numerical modeling of collisions, which predicts the internal

  1. Structural Biology Fact Sheet

    MedlinePlus

    ... Home > Science Education > Structural Biology Fact Sheet Structural Biology Fact Sheet Tagline (Optional) Middle/Main Content Area What is structural biology? Structural biology is a field of science focused ...

  2. Structured Data in Structural Analysis Software

    NASA Technical Reports Server (NTRS)

    Kunz, Donald L.; Hopkins, Stewart

    1987-01-01

    This paper discusses the use of computer data structures in finite-element structural analysis programs. A number of data structure types that have been shown to be useful in such programs are introduced and described. A simple finite-element model is used to demonstrate how the given set of data structure types naturally lend themselves to developing software for the model. Different methods of implementing data structures in the context of a program are discussed.

  3. Magnetic multilayer structure

    DOEpatents

    Herget, Philipp; O'Sullivan, Eugene J.; Romankiw, Lubomyr T.; Wang, Naigang; Webb, Bucknell C.

    2016-07-05

    A mechanism is provided for an integrated laminated magnetic device. A substrate and a multilayer stack structure form the device. The multilayer stack structure includes alternating magnetic layers and diode structures formed on the substrate. Each magnetic layer in the multilayer stack structure is separated from another magnetic layer in the multilayer stack structure by a diode structure.

  4. [Diversity, structure and regeneration of the seasonally dry tropical forest of Yucatán Peninsula, Mexico].

    PubMed

    Hernández-Ramírez, Angélica María; García-Méndez, Socorro

    2015-09-01

    Seasonally dry tropical forests are considered as the most endangered ecosystem in lowland tropics. The aim of this study was to characterize the floristic composition, richness, diversity, structure and regeneration of a seasonally dry tropical forest landscape constituted by mature forest, secondary forest and seasonally inundated forest located in the Northeastern part of the Yucatán Peninsula, Mexico. We used the Gentry's standard inventory plot methodology (0.1 ha per forest type in 2007) for facilitating comparison with other Mesoamerican seasonally dry tropical forests. A total of 77 species belonging to 32 families were observed in the study area. Fabaceae and Euphorbiaceae were the families with the largest taxonomic richness in the three forest types. Low levels of β diversity were observed among forest types (0.19-0.40), suggesting a high turnover of species at landscape level. The non-regenerative species were dominant (50-51 %), followed by regenerative species (30- 28 %), and colonizer species (14-21 %) in the three forest types. Zoochory was the most common dispersal type in the study area. The 88 % of the observed species in the study area were distributed in Central America. Some floristic attributes of the seasonally dry tropical forest of the Yucatán Peninsula, fall into the values reported for Mesoamerican seasonally dry tropical forests. Natural disturbances contributed to explain the high number of individuals, the low number of liana species, as well as the low values of basal area observed in this study. Our results suggested that the seasonally dry tropical forest of Yucatán Peninsula seems to be resilient to natural disturbances (hurricane) in terms of the observed number of species and families, when compared with the reported values in Mesoamerican seasonally dry tropical forests. Nonetheless, the recovery and regeneration of vegetation in long-term depends on animal-dispersed species. This study highlights the importance of

  5. [Diversity, structure and regeneration of the seasonally dry tropical forest of Yucatán Peninsula, Mexico].

    PubMed

    Hernández-Ramírez, Angélica María; García-Méndez, Socorro

    2015-09-01

    Seasonally dry tropical forests are considered as the most endangered ecosystem in lowland tropics. The aim of this study was to characterize the floristic composition, richness, diversity, structure and regeneration of a seasonally dry tropical forest landscape constituted by mature forest, secondary forest and seasonally inundated forest located in the Northeastern part of the Yucatán Peninsula, Mexico. We used the Gentry's standard inventory plot methodology (0.1 ha per forest type in 2007) for facilitating comparison with other Mesoamerican seasonally dry tropical forests. A total of 77 species belonging to 32 families were observed in the study area. Fabaceae and Euphorbiaceae were the families with the largest taxonomic richness in the three forest types. Low levels of β diversity were observed among forest types (0.19-0.40), suggesting a high turnover of species at landscape level. The non-regenerative species were dominant (50-51 %), followed by regenerative species (30- 28 %), and colonizer species (14-21 %) in the three forest types. Zoochory was the most common dispersal type in the study area. The 88 % of the observed species in the study area were distributed in Central America. Some floristic attributes of the seasonally dry tropical forest of the Yucatán Peninsula, fall into the values reported for Mesoamerican seasonally dry tropical forests. Natural disturbances contributed to explain the high number of individuals, the low number of liana species, as well as the low values of basal area observed in this study. Our results suggested that the seasonally dry tropical forest of Yucatán Peninsula seems to be resilient to natural disturbances (hurricane) in terms of the observed number of species and families, when compared with the reported values in Mesoamerican seasonally dry tropical forests. Nonetheless, the recovery and regeneration of vegetation in long-term depends on animal-dispersed species. This study highlights the importance of

  6. Computational structural mechanics for engine structures

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.

    1989-01-01

    The computational structural mechanics (CSM) program at Lewis encompasses: (1) fundamental aspects for formulating and solving structural mechanics problems, and (2) development of integrated software systems to computationally simulate the performance/durability/life of engine structures. It is structured to mainly supplement, complement, and whenever possible replace, costly experimental efforts which are unavoidable during engineering research and development programs. Specific objectives include: investigate unique advantages of parallel and multiprocesses for: reformulating/solving structural mechanics and formulating/solving multidisciplinary mechanics and develop integrated structural system computational simulators for: predicting structural performances, evaluating newly developed methods, and for identifying and prioritizing improved/missing methods needed. Herein the CSM program is summarized with emphasis on the Engine Structures Computational Simulator (ESCS). Typical results obtained using ESCS are described to illustrate its versatility.

  7. Oberholzeria (Fabaceae subfam. Faboideae), a New Monotypic Legume Genus from Namibia

    PubMed Central

    Swanepoel, Wessel; le Roux, M. Marianne; Wojciechowski, Martin F.; van Wyk, Abraham E.

    2015-01-01

    Oberholzeria etendekaensis, a succulent biennial or short-lived perennial shrublet is described as a new species, and a new monotypic genus. Discovered in 2012, it is a rare species known only from a single locality in the Kaokoveld Centre of Plant Endemism, north-western Namibia. Phylogenetic analyses of molecular sequence data from the plastid matK gene resolves Oberholzeria as the sister group to the Genisteae clade while data from the nuclear rDNA ITS region showed that it is sister to a clade comprising both the Crotalarieae and Genisteae clades. Morphological characters diagnostic of the new genus include: 1) succulent stems with woody remains; 2) pinnately trifoliolate, fleshy leaves; 3) monadelphous stamens in a sheath that is fused above; 4) dimorphic anthers with five long, basifixed anthers alternating with five short, dorsifixed anthers, and 5) pendent, membranous, one-seeded, laterally flattened, slightly inflated but indehiscent fruits. PMID:25816251

  8. Isolation and characterisation of plant defensins from seeds of Asteraceae, Fabaceae, Hippocastanaceae and Saxifragaceae.

    PubMed

    Osborn, R W; De Samblanx, G W; Thevissen, K; Goderis, I; Torrekens, S; Van Leuven, F; Attenborough, S; Rees, S B; Broekaert, W F

    1995-07-17

    From seeds of Aesculus hippocastanum, Clitoria ternatea, Dahlia merckii and Heuchera sanguinea five antifungal proteins were isolated and shown to be homologous to plant defensins previously characterised from radish seeds and gamma-thionins from Poaceae seeds. Based on the spectrum of their antimicrobial activity and the morphological distortions they induce on fungi the peptides can be divided into two classes. The peptides did not inhibit any of three different alpha-amylases. PMID:7628617

  9. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus)

    PubMed Central

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants. PMID:27324580

  10. Contrasting evolution of a satellite DNA and its ancestral IGS rDNA in Phaseolus (Fabaceae).

    PubMed

    Almeida, Cícero; Fonsêca, Artur; dos Santos, Karla Galvão Bezerra; Mosiolek, Magdalena; Pedrosa-Harand, Andrea

    2012-09-01

    CC4 is a satellite DNA from common bean (Phaseolus vulgaris L.) that is similar to its intergenic spacer (IGS) rDNA. CC4 was originally hypothesized to be an old, fast evolving satellite family that has invaded common bean rDNA. To test this hypothesis and contribute to the understanding of IGS-like satellite DNA evolution, we have investigated its distribution in the genus Phaseolus and related species. CC4 was cloned and used as probe for Southern blot and FISH experiments. CC4 was observed as an independent satellite in common bean, forming two to three major and a few minor pericentromeric clusters. In Phaseolus coccineus, CC4 was present in four major clusters, also not co-localized with the 45S rDNA sites. Remarkably, in the less related species of the genus, signals were detected co-localized with the 45S rDNA sites, but co-localization was not observed in the species where CC4 is present as an independent satellite. No signal was detected in species from related genera. Altogether, the data suggest that CC4 has originated from the IGS rDNA in the P. vulgaris-P. coccineus lineage and has evolved slower than the IGS rDNA from this lineage.

  11. Breeding biology and incremental benefits of outcrossing for the restoration wildflower, Hedysarum boreale (Fabaceae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Northern sweetvetch, Hedysarum boreale, is an herbaceous perennial of the Rocky Mountains whose seed is desired for rehabilitating degraded plant communities. Through experimental manual pollinations, the necessity of pollinators was shown by the failures of autopollination and wind pollination, ev...

  12. INBREEDING EFFECTS IN WILD LUPINE (FABACEAE): DOES POPULATION SIZE MATTER? (R826596)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  13. Antibacterial activity of endophytic fungi from leaves of Indigofera suffruticosa Miller (Fabaceae).

    PubMed

    Dos Santos, Irailton Prazeres; da Silva, Luís Cláudio Nascimento; da Silva, Márcia Vanusa; de Araújo, Janete Magali; Cavalcanti, Marilene da Silva; Lima, Vera Lucia de Menezes

    2015-01-01

    Endophytic fungi were isolated from healthy leaves of Indigofera suffruticosa Miller, a medicinal plant found in Brazil which is used in folk medicine to treat various diseases. Among 65 endophytic fungi isolated, 18 fungi showed activity against at least one tested microorganism in preliminary screening, and the best results were obtained with Nigrospora sphaerica (URM-6060) and Pestalotiopsis maculans (URM-6061). After fermentation in liquid media and in semisolid media, only N. sphaerica demonstrated antibacterial activity (in Potato Dextrose Broth-PDB and in semisolid rice culture medium). In the next step, a methanolic extract from rice culture medium (NsME) and an ethyl acetate extract (NsEAE) from the supernatant of PDB were prepared and both exhibited antimicrobial activity against Gram-negative and Gram-positive bacteria. The best result was observed against Staphylococcus aureus, with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 1.56 mg/mL and 6.25 mg/mL, respectively, for NsME and MIC and MBC values of 0.39 mg/mL and 3.12 mg/mL, respectively, for NsEAE. This study is the first report about the antimicrobial activity of endophytic fungi residing in I. suffruticosa leaves, in which the fungus N. sphaerica demonstrated the ability to produce bioactive agents with pharmaceutical potential, and may provide a new lead in the pursuit of new biological sources of drug candidates.

  14. Antibacterial activity of endophytic fungi from leaves of Indigofera suffruticosa Miller (Fabaceae)

    PubMed Central

    dos Santos, Irailton Prazeres; da Silva, Luís Cláudio Nascimento; da Silva, Márcia Vanusa; de Araújo, Janete Magali; Cavalcanti, Marilene da Silva; Lima, Vera Lucia de Menezes

    2015-01-01

    Endophytic fungi were isolated from healthy leaves of Indigofera suffruticosa Miller, a medicinal plant found in Brazil which is used in folk medicine to treat various diseases. Among 65 endophytic fungi isolated, 18 fungi showed activity against at least one tested microorganism in preliminary screening, and the best results were obtained with Nigrospora sphaerica (URM-6060) and Pestalotiopsis maculans (URM-6061). After fermentation in liquid media and in semisolid media, only N. sphaerica demonstrated antibacterial activity (in Potato Dextrose Broth-PDB and in semisolid rice culture medium). In the next step, a methanolic extract from rice culture medium (NsME) and an ethyl acetate extract (NsEAE) from the supernatant of PDB were prepared and both exhibited antimicrobial activity against Gram-negative and Gram-positive bacteria. The best result was observed against Staphylococcus aureus, with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 1.56 mg/mL and 6.25 mg/mL, respectively, for NsME and MIC and MBC values of 0.39 mg/mL and 3.12 mg/mL, respectively, for NsEAE. This study is the first report about the antimicrobial activity of endophytic fungi residing in I. suffruticosa leaves, in which the fungus N. sphaerica demonstrated the ability to produce bioactive agents with pharmaceutical potential, and may provide a new lead in the pursuit of new biological sources of drug candidates. PMID:25999918

  15. First comparative phenetic studies of Argentinean species of Acacia (Fabaceae), using morphometric, isozymal, and RAPD approaches.

    PubMed

    Casiva, Paola V; Saidman, Beatriz O; Vilardi, Juan C; Cialdella, Ana M

    2002-05-01

    Morphological and genetic diversity among Acacia aroma, A. macracantha, A. caven, and A. furcatispina were studied with morphometric, isozymal, and RAPD approaches. The analysis of seven isozyme systems revealed 21 loci, and RAPD analysis showed 34 loci. Most of these loci allowed us to differentiate the species, with the exception of A. aroma and A. macracantha, the two most similar species. The levels of genetic variability estimated by isozymes were higher than those obtained from RAPD analyses. Morphometric characters showed highly significant differences among the species, although A. aroma and A. macracantha are differentiated only by thorn length. The phenogram obtained from isozyme data is consistent with morphological data. The RAPD phenogram based on allelic frequencies showed agreement with morphological and isozymal approaches only at the intraspecific levels, while the RAPD phenogram based on Nei and Li's similarity measures agreed with the phenograms constructed from isozyme and morphological data. High similarities and high indirect gene flow were found between A. aroma and A. macracantha, results that call the relationship between them into question. PMID:21665685

  16. Pollen source and resource limitation to fruit production in the rare species Eremosparton songoricum (Fabaceae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eremosparton songoricum (Litv.) Vass. is a rare, central Asian desert species which shows lower fruit set and seed set (<16%) than most hermaphroditic species. We hypothesized that fruit production was limited by pollen and resources. To evaluate potential fruit abortion due to pollen limitation, su...

  17. Ultrastructural changes of the egg apparatus associated with fertilisation of natural tetraploid Trifolium pratense L. (Fabaceae).

    PubMed

    Buyukkartal, H Nurhan Bakar

    2009-01-01

    The aim of this study is to describe the ultrastructural changes of the egg apparatus associated with fertilisation of the natural tetraploid Trifolium pratense. The pollen tube enters one of the synergids through the filliform apparatus from the micropyle. Before the entry of the pollen tube into the embryo sac, one of the synergids begins to degenerate, as indicated by increased electron density and a loss of volume. This cell serves as the site of entry for the pollen tube. Following fertilization, the vacuolar organisation in the zygote changes; in addition to the large micropylar vacuole, there are several small vacuoles of varying size. Ribosomal concentration increases significantly after fertilisation. In T. pratense, ultrastructural changes between the egg cell and zygote stages are noticeable. Several marked changes occur in the egg cell because of fertilisation. The zygote cell contains ribosomes has many mitochondria, plastids, lipids, vacuoles. After fertilization, most of the food reserves are located in the integument in the form of starch. The zygote shows ultrastructural changes when compared to the egg cell and appears to be metabolically active.

  18. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus).

    PubMed

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants.

  19. First record of Sesbania punicea (Fabales: Fabaceae) as a host plant for Chinavia hilaris (Hemiptera: Pentatomidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The green stink bug, Chinavia hilaris (Say) (Hemiptera: Pentatomidae), is an economic pest of cotton, Gossypium hirsutum L. Numerous known non-crop hosts of C. hilaris that exist in field edges bordering cotton are sources of this stink bug in this crop. Sesbania punicea plants in a field border su...

  20. Species delimitation and recognition in the Pediomelum megalanthum complex (Fabaceae) via multivariate morphometrics

    PubMed Central

    Egan, Ashley N.

    2015-01-01

    Abstract Pediomelum is a genus endemic to North America comprising about 26 species, including the megalanthum complex, which consists of Pediomelum megalanthum and its varieties retrorsum and megalanthum, Pediomelum mephiticum, and the recently described Pediomelum verdiense and Pediomelum pauperitense. Historically, species of the megalanthum complex have been variably recognized at the species or variety levels, dependent upon the relative importance of morphological characters as diagnostic of species. Ten quantitative morphological characters regarded as diagnostic at the species level were analyzed using multivariate morphometrics across these taxa in order to examine the discriminatory power of these characters to delineate species and to aid in species delimitation. The analyses support the recognition of Pediomelum megalanthum, Pediomelum mephiticum, and Pediomelum verdiense at the species level, Pediomelum retrorsum as a variety under Pediomelum megalanthum, and suggest the sinking of Pediomelum pauperitense into Pediomelum verdiense. The findings of the present study help quantify the power of certain characters at delimiting taxa and provide a basis for taxonomic revision of the Pediomelum megalanthum complex. PMID:25698894

  1. Molecular phylogenetics of Amorpha (Fabaceae): an evaluation of monophyly, species relationships, and polyploid origins.

    PubMed

    Straub, Shannon C K; Doyle, Jeff J

    2014-07-01

    Amorpha L. (false indigos and lead plants) is a North American legume genus of 16 species of shrubs, which is most diverse in the southeastern United States and distinctive due to the reduction of the corolla to a single petal. Most species have limited distributions, but the tetraploid A. fruticosa species complex is widely distributed and its range overlaps those of all of the other species. Morphological variation in the genus is characterized by gradation of characters among species and it has been the subject of repeated taxonomic study due to the difficulty in delimiting species, especially among A. fruticosa and allies. This study presents the first phylogenetic and network analyses for evaluation of relationships amongst Amorpha species based on three non-coding plastome regions (trnD-trnT, trnH-psbA, petN-psbM) and two low-copy nuclear genes (CNGC5, minD). Plastid DNA analyses supported a monophyletic Amorpha with Parryella filifolia and Errazurizia rotundata as successive sister lineages; however, nuclear gene analyses supported the nesting of these two species and thus a paraphyletic Amorpha. Relationships among species of Amorpha were best resolved in the plastid DNA phylogeny and in most cases were concordant with expectations based on morphology. Relationships based on the nuclear gene phylogenies were less clear due to lack of informative variation (CNGC5) or conflict in the data set (minD). The origins of A. fruticosa were unclear, but the plastid phylogeny revealed that this species shares the same or similar plastid haplotype as other species in a geographic region. Putative recombination of diploid species' alleles was evident in the minD-like network. Phenotypic plasticity in combination with gene flow into this species from different diploids, or even tetraploids, across its range may account for the incredible morphological diversity of the A. fruticosa species complex. Putative progenitors for two other suspected allotetraploid species, A. confusa and A. crenulata, were identified as A. fruticosa and A. herbacea.

  2. EFFECTS OF PLANT SIZE ON PHOTOSYNTHESIS AND WATER RELATIONS IN THE DESERT SHRUB PROSOPIS GLANDULOSA (FABACEAE)

    EPA Science Inventory

    The Jornada del Muerto basin of the Chihuahuan Desert of southern New Mexico, USA, has undergone a marked transition of plant communities. Shrubs such as mesquite (Prosopis glandulosa) have greatly increased or now dominate in areas that were previously dominated by perennial gra...

  3. Insecticidal and genotoxic activity of Psoralea corylifolia Linn. (Fabaceae) against Culex quinquefasciatus Say, 1823

    PubMed Central

    2013-01-01

    Background Indiscriminate use of synthetic insecticides to eradicate mosquitoes has caused physiological resistance. Plants provide a reservoir of biochemical compounds; among these compounds some have inhibitory effect on mosquitoes. In the present study the larvicidal, adulticidal and genotoxic activity of essential oil of Psoralea corylifolia Linn. against Culex quinquefasciatus Say was explored. Methods Essential oil was isolated from the seeds of P. corylifolia Linn. Larvicidal and adulticidal bioassay of Cx. quinquefasciatus was carried out by WHO method. Genotoxic activity of samples was determined by comet assay. Identification of different compounds was carried out by gas chromatography- mass spectrometry analysis. Results LC50 and LC90 values of essential oil were 63.38±6.30 and 99.02±16.63 ppm, respectively against Cx. quinquefasciatus larvae. The LD50 and LD90 values were 0.057±0.007 and 0.109±0.014 mg/cm2 respectively against adult Cx. quinquefasciatus,. Genotoxicity of adults was determined at 0.034 and 0.069 mg/cm2. The mean comet tail length was 6.2548±0.754 μm and 8.47±0.931 μm and the respective DNA damage was significant i.e. 6.713% and 8.864% in comparison to controls. GCMS analysis of essential oil revealed 20 compounds. The major eight compounds were caryophyllene oxide (40.79%), phenol,4-(3,7-dimethyl-3-ethenylocta-1,6-dienyl) (20.78%), caryophyllene (17.84%), α-humulene (2.15%), (+)- aromadendrene (1.57%), naphthalene, 1,2,3,4-tetra hydro-1,6-dimethyle-4-(1-methyl)-, (1S-cis) (1.53%), trans- caryophyllene (0.75%), and methyl hexadecanoate (0.67%). Conclusion Essential oil obtained from the seeds of P. corylifolia showed potent toxicity against larvae and adult Cx. quinquefasciatus. The present work revealed that the essential oil of P. corylifolia could be used as environmentally sound larvicidal and adulticidal agent for mosquito control. PMID:23379981

  4. Molecular identification and genetic variation of varieties of Styphnolobium japonicum (Fabaceae) using SRAP markers.

    PubMed

    Sun, R X; Zhang, C H; Zheng, Y Q; Zong, Y C; Yu, X D; Huang, P

    2016-01-01

    Thirty-four Styphnolobium japonicum varieties were analyzed using sequence-related amplified polymorphism (SRAP) markers, to investigate genetic variation and test the effectiveness of SRAP markers in DNA fingerprint establishment. Twelve primer pairs were selected from 120 primer combinations for their reproducibility and high polymorphism. We found a total of 430 amplified fragments, of which 415 fragments were considered polymorphic with an average of 34.58 polymorphic fragments for each primer combination. The percentage of polymorphic fragments was 96.60%, and four primer pairs showed 100% polymorphism. Moreover, simple matched coefficients ranged between 0.68 and 0.89, with an average of 0.785, indicating that the genetic variation among varieties was relatively low. This could be because of the narrow genetic basis of the selected breeding material. Based on the similarity coefficient value of 0.76, the varieties were divided into four major groups. In addition, abundant and clear SRAP fingerprints were obtained and could be used to establish DNA fingerprints. In the DNA fingerprints, each variety had its unique pattern that could be easily distinguished from others. The results demonstrated that 34 varieties of S. japonicum had a relatively narrow genetic variation. Hence, a broadening of the genetic basis of breeding material is necessary. We conclude that establishment of DNA fingerprint is feasible by means of SRAP markers. PMID:27173318

  5. Adaptive gains through repeated gene loss: parallel evolution of cyanogenesis polymorphisms in the genus Trifolium (Fabaceae).

    PubMed

    Olsen, Kenneth M; Kooyers, Nicholas J; Small, Linda L

    2014-08-01

    Variation in cyanogenesis (hydrogen cyanide release following tissue damage) was first noted in populations of white clover more than a century ago, and subsequent decades of research have established this system as a classic example of an adaptive chemical defence polymorphism. Here, we document polymorphisms for cyanogenic components in several relatives of white clover, and we determine the molecular basis of this trans-specific adaptive variation. One hundred and thirty-nine plants, representing 13 of the 14 species within Trifolium section Trifoliastrum, plus additional species across the genus, were assayed for cyanogenic components (cyanogenic glucosides and their hydrolysing enzyme, linamarase) and for the presence of underlying cyanogenesis genes (CYP79D15 and Li, respectively). One or both cyanogenic components were detected in seven species, all within section Trifoliastrum; polymorphisms for the presence/absence (PA) of components were detected in six species. In a pattern that parallels our previous findings for white clover, all observed biochemical polymorphisms correspond to gene PA polymorphisms at CYP79D15 and Li. Relationships of DNA sequence haplotypes at the cyanogenesis loci and flanking genomic regions suggest independent evolution of gene deletions within species. This study thus provides evidence for the parallel evolution of adaptive biochemical polymorphisms through recurrent gene deletions in multiple species.

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

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., beans (Phaseolus spp.), Florida beggarweed, black medic, broadbean, burclovers, buttonclover, chickpea.... (b) Adzuki bean, broadbean, chickpea, field pea, lentil, pea, roughpea, runner bean, velvetbean,...

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

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., beans (Phaseolus spp.), Florida beggarweed, black medic, broadbean, burclovers, buttonclover, chickpea.... (b) Adzuki bean, broadbean, chickpea, field pea, lentil, pea, roughpea, runner bean, velvetbean,...

  8. 7 CFR 201.56-6 - Legume or pea family, Fabaceae (Leguminosae).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., beans (Phaseolus spp.), Florida beggarweed, black medic, broadbean, burclovers, buttonclover, chickpea.... (b) Adzuki bean, broadbean, chickpea, field pea, lentil, pea, roughpea, runner bean, velvetbean,...

  9. 7 CFR 201.56-6 - Legume or pea family, Fabaceae (Leguminosae).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., beans (Phaseolus spp.), Florida beggarweed, black medic, broadbean, burclovers, buttonclover, chickpea.... (b) Adzuki bean, broadbean, chickpea, field pea, lentil, pea, roughpea, runner bean, velvetbean,...

  10. Spatiotemporal Evolution of Calophaca (Fabaceae) Reveals Multiple Dispersals in Central Asian Mountains

    PubMed Central

    Zhang, Ming-Li; Wen, Zhi-Bin; Fritsch, Peter W.; Sanderson, Stewart C.

    2015-01-01

    Background The Central Asian flora plays a significant role in Eurasia and the Northern Hemisphere. Calophaca, a member of this flora, includes eight currently recognized species, and is centered in Central Asia, with some taxa extending into adjacent areas. A phylogenetic analysis of the genus utilizing nuclear ribosomal ITS and plastid trnS-trnG and rbcL sequences was carried out in order to confirm its taxonomic status and reconstruct its evolutionary history. Methodology/Principal Finding We employed BEAST Bayesian inference for dating, and S-DIVA and BBM for ancestral area reconstruction, to study its spatiotemporal evolution. Our results show that Calophacais monophyletic and nested within Caragana. The divergence time of Calophaca is estimated at ca. 8.0 Ma, most likely driven by global cooling and aridification, influenced by rapid uplift of the Qinghai Tibet Plateau margins. Conclusions/Significance According to ancestral area reconstructions, the genus most likely originated in the Pamir Mountains, a global biodiversity hotspot and hypothesized Tertiary refugium of many Central Asian plant lineages. Dispersals from this location are inferred to the western Tianshan Mountains, then northward to the Tarbagatai Range, eastward to East Asia, and westward to the Caucasus, Russia, and Europe. The spatiotemporal evolution of Calophaca provides a case contributing to an understanding of the flora and biodiversity of the Central Asian mountains and adjacent regions. PMID:25849146

  11. Antidermatophytic activity of extracts from Psoralea corylifolia (Fabaceae) correlated with the presence of a flavonoid compound.

    PubMed

    Rajendra Prasad, N; Anandi, C; Balasubramanian, S; Pugalendi, K V

    2004-03-01

    Extracts obtained from seeds of Psoralea corylifolia showed several degrees of antifungal activity against Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum and Microsporum gypseum by the disc diffusion method on a Sabouraud dextrose agar (SDA) medium. Methanol extract of the seeds at 250 microg exhibited the maximum inhibition with a halo of 28 mm diameter. Six different bands were obtained when the methanol extract was subjected to TLC. 13C NMR and Mass spectra revealed that the active compound would be a flavonoid, 4'-methoxy flavone. MIC of the active compound along with standard miconazole was carried out using tube dilution technique. PMID:15036462

  12. Antinociceptive Activity of the Chloroform Fraction of Dioclea virgata (Rich.) Amshoff (Fabaceae) in Mice

    PubMed Central

    Mota, Vanine Gomes; de Carvalho, Fabíola Lélis; de Morais, Liana Clébia Soares Lima; Bhattacharyya, Jnanabrata; de Almeida, Reinaldo Nóbrega; de Alencar, Jacicarlos Lima

    2011-01-01

    Acute treatment with the chloroform fraction of Dioclea virgata (Rich.) Amshoff (CFDv) in mice produced decreased ambulation and sedation in the behavioral pharmacological screening. Doses of 125 and 250 mg/kg CFDv decreased latency of sleep onset in the test of sleeping time potentiation. In the open field, animals treated with CFDv reduced ambulation and rearing (250 mg/kg), as well as defecation (125; 250 mg/kg). Regarding the antinociceptive activity, CFDv (125, 250, 500 mg/kg) increased latency to first writhing and decreased the number of writhings induced by acetic acid. In the formalin test, CFDv (250 mg/kg) decreased paw licking time in the first and second phases indicating antinociceptive activity that can be mediated both peripherally and at the central level. CFDv did not affect motor coordination until 120 minutes after treatment. CFDv shows psychopharmacological effects suggestive of CNS-depressant drugs with promising antinociceptive activity. PMID:21776190

  13. Flower Morphology, Pollination Biology and Mating System of the Complex Flower of Vigna caracalla (Fabaceae: Papilionoideae)

    PubMed Central

    Etcheverry, Angela Virginia; Alemán, Maria Mercedes; Fleming, Trinidad Figueroa

    2008-01-01

    Background and Aims Vigna caracalla has the most complex flower among asymmetrical Papilionoideae. The objective of this study was to understand the relationships among floral characteristics, specialization, mating system and the role of floral visitors under different ecological contexts. Methods Five populations were studied in north-western Argentina, from 700 to 1570 m a.s.l. Anthesis, colour and odour patterns, stigmatic receptivity, visitors and pollination mechanism were examined and mating-system experiments were performed. Key Results The petals are highly modified and the keel shows 3·75–5·25 revolutions. The sense of asymmetry was always left-handed. Hand-crosses showed that V. caracalla is self-compatible, but depends on pollinators to set seeds. Hand-crossed fruits were more successful than hand-selfed ones, with the exception of the site at the highest elevation. Bombus morio (queens and workers), Centris bicolor, Eufriesea mariana and Xylocopa eximia trigger the pollination mechanism (a ‘brush type’). The greatest level of self-compatibility and autonomous self-pollination were found at the highest elevation, together with the lowest reproductive success and number of pollinators (B. morio workers only). Conclusions Self-fertilization may have evolved in the peripheral population at the highest site of V. caracalla because of the benefits of reproductive assurance under reduced pollinator diversity. PMID:18587133

  14. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus).

    PubMed

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants. PMID:27324580

  15. Fruits of Mimosa foliolosa (Fabales: Fabaceae) as sleeping shelter for Megachile (Pseudocentron) botucatuna (Hymenoptera: Megachilidae).

    PubMed

    Fernandes, G W; Ferrari, R R

    2012-12-01

    Several plant parts or organs are often used by insects for aggregation and even as resting areas. We first report the use of fruits of the legume Mimosa foliolosa pachycarpa as a night shelter for Megachile (Pseudocentron) botucana Schrottky (Hymenoptera: Megachilidae) in Serra do Cipó, southeastern Brazil. Only a single bee was found per fruit, in 86 fruits out of 1,003 fruits opened. The present findings augmented the occurrence of the phenomenon among bees, which is new to the harsh mountaintop environments in the Brazilian rupestrian fields. PMID:23949678

  16. COX-2 inhibitors from stem bark of Bauhinia rufescens Lam. (Fabaceae)

    PubMed Central

    Muhammad, Aminu; Sirat, Hasnah Mohd

    2013-01-01

    Chemical investigation of the stem bark of Bauhinia rufescens resulted in the isolation of a new cyanoglucoside and menisdaurin from methanol extract and oxepin from petroleum ether extract. The isolated compounds were tested for their anti-inflammatory potentials based on the cyclooxygenase-2 enzyme (COX-2) model. Cyanoglucoside exhibited the highest activity among the compounds with an inhibition activity of 49.34 % at 100 µM (IC50 0.46 µM) compared to the positive control, indomethacin (79.20 %, IC50 0.24 µM). PMID:26600739

  17. New species of Tetradiplosis (Diptera: Cecidomyiidae) inducing galls on Prosopis caldenia (Fabaceae) in Argentina.

    PubMed

    Martínez, Juan José; Corró-molas, Barbara; Alfonso, Graciela L

    2013-01-01

    Two new species of Tetradiplosis inducing galls on Prosopis caldenia are described from Argentina: Tetradiplosis panghitruz Martínez n. sp. and Tetradiplosis rayen Martínez n. sp. Tetradiplosispanghitruz induces multilocular galls on vegetative stems, whereas T. rayen induces unilocular galls containing multiple larvae on the rachis of the developing inflorescences. The adult male, female, pupa and larva are described and illustrated for both species. A key to the known species of the genus is provided.

  18. In Vitro Seeds Germination and Seedling Growth of Bambara Groundnut (Vigna subterranea (L.) Verdc. (Fabaceae))

    PubMed Central

    Koné, Mongomaké; Koné, Tchoa; Silué, Nakpalo; Soumahoro, André Brahima; Kouakou, Tanoh Hilaire

    2015-01-01

    Bambara groundnut (Vigna subterranea (L.) Verdc.) is an indigenous grain legume. It occupies a prominent place in the strategies to ensure food security in sub-Saharan Africa. Development of an efficient in vitro regeneration system, a prerequisite for genetic transformation application, requires the establishment of optimal conditions for seeds germination and plantlets development. Three types of seeds were inoculated on different basal media devoid of growth regulators. Various strengths of the medium of choice and the type and concentration of carbon source were also investigated. Responses to germination varied with the type of seed. Embryonic axis (EA) followed by seeds without coat (SWtC) germinated rapidly and expressed a high rate of germination. The growth performances of plantlets varied with the basal medium composition and the seeds type. The optimal growth performances of plants were displayed on half strength MS basal medium with SWtC and EA as source of seeds. Addition of 3% sucrose in the culture medium was more suitable for a maximum growth of plantlets derived from EA. PMID:26550604

  19. Oberholzeria (Fabaceae subfam. Faboideae), a new monotypic legume genus from Namibia.

    PubMed

    Swanepoel, Wessel; le Roux, M Marianne; Wojciechowski, Martin F; van Wyk, Abraham E

    2015-01-01

    Oberholzeria etendekaensis, a succulent biennial or short-lived perennial shrublet is described as a new species, and a new monotypic genus. Discovered in 2012, it is a rare species known only from a single locality in the Kaokoveld Centre of Plant Endemism, north-western Namibia. Phylogenetic analyses of molecular sequence data from the plastid matK gene resolves Oberholzeria as the sister group to the Genisteae clade while data from the nuclear rDNA ITS region showed that it is sister to a clade comprising both the Crotalarieae and Genisteae clades. Morphological characters diagnostic of the new genus include: 1) succulent stems with woody remains; 2) pinnately trifoliolate, fleshy leaves; 3) monadelphous stamens in a sheath that is fused above; 4) dimorphic anthers with five long, basifixed anthers alternating with five short, dorsifixed anthers, and 5) pendent, membranous, one-seeded, laterally flattened, slightly inflated but indehiscent fruits.

  20. The generalist Inga subnuda subsp. luschnathiana (Fabaceae): negative effect of floral visitors on reproductive success?

    PubMed

    Avila, R; Pinheiro, M; Sazima, M

    2015-05-01

    Inga species are characterised by generalist or mixed pollination system. However, this feature does not enhance reproductive rates in species with very low fruit set under natural conditions. Some ecological and genetic factors are associated with this feature, and to test the effect of massive visits on pollination success in Inga subnuda subsp. luschnathiana, we studied the efficacy of polyads deposited on stigmas of flowers isolated from visitors and polyads exposed to visitors. The proportion of polyads fixed in stigmas decreased after exposure to visitors (24 h) in comparison to stigmas isolated from visitors (hummingbirds, bees, wasps, hawkmoths and bats), and fruit set was very low. Furthermore, nectar production, sugar composition and other floral biology traits were evaluated. Increased nectar production, sugar availability and sucrose dominance during the night indicates adaptation to nocturnal visitors and supports their role as main pollinators; although the brush-flower morphology, time of anthesis, nectar dynamics and chemical composition also allow daytime visitors. Thus the species is an important resource for a diverse group of floral visitors. We conclude that excess visits (diurnal and nocturnal) are responsible for the decrease in fixed polyads in stigmas of I. subnuda subsp. luschnathiana flowers, thus contributing, with others factors, to its low fruit set. Therefore, the generalist pollination system does not result in reproductive advantages because the low fruit set in natural conditions could be the result of a negative effect of visitors/pollinators.

  1. Molecular cytogenetic characterisation and phylogenetic analysis of the seven cultivated Vigna species (Fabaceae).

    PubMed

    She, C-W; Jiang, X-H; Ou, L-J; Liu, J; Long, K-L; Zhang, L-H; Duan, W-T; Zhao, W; Hu, J-C

    2015-01-01

    The genomic organisation of the seven cultivated Vigna species, V. unguiculata, V. subterranea, V. angularis, V. umbellata, V. radiata, V. mungo and V. aconitifolia, was determined using sequential combined PI and DAPI (CPD) staining and dual-colour fluorescence in situ hybridisation (FISH) with 5S and 45S rDNA probes. For phylogenetic analyses, comparative genomic in situ hybridisation (cGISH) onto somatic chromosomes and sequence analysis of the internal transcribed spacer (ITS) of 45S rDNA were used. Quantitative karyotypes were established using chromosome measurements, fluorochrome bands and rDNA FISH signals. All species had symmetrical karyotypes composed of only metacentric or metacentric and submetacentric chromosomes. Distinct heterochromatin differentiation was revealed by CPD staining and DAPI counterstaining after FISH. The rDNA sites among all species differed in their number, location and size. cGISH of V. umbellata genomic DNA to the chromosomes of all species produced strong signals in all centromeric regions of V. umbellata and V. angularis, weak signals in all pericentromeric regions of V. aconitifolia, and CPD-banded proximal regions of V. mungo var. mungo. Molecular phylogenetic trees showed that V. angularis and V. umbellata were the closest relatives, and V. mungo and V. aconitifolia were relatively closely related; these species formed a group that was separated from another group comprising V. radiata, V. unguiculata ssp. sesquipedalis and V. subterranea. This result was consistent with the phylogenetic relationships inferred from the heterochromatin and cGISH patterns; thus, fluorochrome banding and cGISH are efficient tools for the phylogenetic analysis of Vigna species.

  2. Comparative polyphenolic content and antioxidant activities of Genista tinctoria L. and Genistella sagittalis (L.) Gams (Fabaceae).

    PubMed

    Hanganu, Daniela; Olah, Neli Kinga; Benedec, Daniela; Mocan, Andrei; Crisan, Gianina; Vlase, Laurian; Popica, Iulia; Oniga, Ilioara

    2016-01-01

    The aim of this study was focused on the polyphenolic composition and antioxidant capacity of Genista tinctoria L. and Genistella sagittalis (L.) Gams. A qualitative and quantitative characterization of the main phenolic compounds from the extracts were carried out using a HPLC-MS method. The total polyphenolic and flavonoid content was spectrophotometrically determined. The antioxidant activity towards various radicals generated in different systems was evaluated usingDPPH bleaching method, Trolox equivalent antioxidant capacity assay (TEAC) and Oxygen radical absorbance capacity (ORAC), and all indicated that G. tinctoria extract was more antioxidant than G. sagittalis extract.That was in good agreement with the total polyphenolic and flavonoidic content.Chlorogenic acid, p-coumaric acid, isoquercitrin and apigenin were identified in bothspecies. Caffeic acid, ferulic acid, hyperoside, rutin, quercitrin and luteolin were found only in G. tinctoria, while quercetin was determined in G. sagittalis.

  3. Antioxidant capacity and fatty acid composition of different parts of Adenocarpus complicatus (Fabaceae) from Turkey.

    PubMed

    Berber, Adnan; Zengin, Gokhan; Aktumsek, Abdurrahman; Sanda, Murad Aydin; Uysal, Tuna

    2014-03-01

    Adenocarpus complicatus is distributed throughout the Anatolian peninsula and is widely used for human and animal nutrition. The purpose of this work was to study the antioxidant properties and fatty acid composition of different parts of this plant (fruits and mixed materials). The species was collected from Golyuzu village of the Seydisehir district near Konya province, Turkey. Fruit and mixed parts obtained from this species were ground and a 15g sample was used to prepare methanolic extracts. Powdered plant samples were extracted with 100mL methanol in a mechanical shaker. The obtained extracts were filtered and concentrated to dryness under reduced pressure and were subsequently stored at -20 degrees C. Antioxidant components, namely total phenolic and flavonoid content, were detected for each extract using spectrophotometric methods. Antioxidant capacity was evaluated by various assays including phosphomolybdenum, DPPH free radical scavenging capacity, metal chelating activity, and ferric and cupric ion reducing power. The fatty acid profiles of plant parts were also determined by using gas chromatography. The total phenolic content of fruit (36.21mgGAE/g) was higher than that of mixed materials (13.79mgGAE/g). The methanolic extract of mixed material had higher amounts of flavonoid than fruit extract. The free radical scavenging activity of extracts was expressed as IC50 value (microg/mL) (amount required to inhibit DPPH radical formation by 50%). The lower IC50 value reflects better free radical scavenging action. The radical scavenging activity of the samples was compared with BHT, it showed the mixed material to be almost two times more potent than the fruit extract. However, BHT is an excellent free radical scavenger with an IC50 of 34.061 microg/mL. The ferric and cupric reducing power potentials of the extracts were expressed as EC50 value (the effective concentration at which the absorbance was 0.5). Fruit extract exhibited strong ferric reducing power with an EC50 of 871.25 microg/mL. The metal chelating activity of the extracts increased with concentration. Chelating effect was 83.60% for fruit extract at 1mg/mL concentration. Oil content of fruit and mixed parts were detected as 6.71 and 6.14%, respectively. A total of 32 fatty acids were found in the oil. Essential fatty acids (linoleic and a-linolenic acid) were identified as the most abundant fatty acids in the oil. These results demonstrated that this plant species can be considered as an alternative to synthetic antioxidants. Likewise, the oil obtained from the plant can be used as a source of essential fatty acids for food and pharmacological applications.

  4. Morphology and genetics of Anadenanthera colubrina var. cebil (Fabaceae) tree from salta (Northwestern Argentina).

    PubMed

    de Viana, Marta L; Giamminola, Eugenia; Russo, Roberta; Ciaccio, Mirella

    2014-06-01

    Anadenanthera colubrina var. cebil is an important tree species for its cultural, economic, and medicinal uses in South America. In order to characterize A. colubrina populations, we collected fruits from four different sites (San Bernardo, El Cebilar, Metán and El Gallinato) within the species distribution area in Salta Province, Northwestern Argentina. For this, a total of 75 fruits and seeds per site were collected and described using morphological (fruits size and weight; seed weight and number per fruit) and genetic descriptors (ribosomic DNA extraction and PCR; nucleotide alignment and phylogenetic analysis) with standard protocols. Our results showed that the San Bernardo population had the heaviest fruits and seeds (7.89 +/- 0.2g and 0.19 +/- 0.002, respectively), and the Cebilar population the lightest (6.25 +/- 0.18g and 0.15 +/- 0.002g, respectively). Fruits and seeds from Metán and El Gallinato showed similar and intermediate values. The proportion viable (39 to 55%) and aborted (43 to 57%) seeds was different, while the proportion of predated (1.7 to 4.2%) seeds was similar among populations. The genetic analysis showed variability of ITS sequences within the especies, and also when compared with the same Brazilian species. Both, morphologic and genetic descriptors showed a high level of similarity between San Bernardo and Metán, and between El Cebilar and El Gallinato populations. Further studies are needed to assess levels of phenotypic and genetic variability within and between populations of different plant species, since this information is crucial for biodiversity and germplasm long-term conservation.

  5. In Vitro Seeds Germination and Seedling Growth of Bambara Groundnut (Vigna subterranea (L.) Verdc. (Fabaceae)).

    PubMed

    Koné, Mongomaké; Koné, Tchoa; Silué, Nakpalo; Soumahoro, André Brahima; Kouakou, Tanoh Hilaire

    2015-01-01

    Bambara groundnut (Vigna subterranea (L.) Verdc.) is an indigenous grain legume. It occupies a prominent place in the strategies to ensure food security in sub-Saharan Africa. Development of an efficient in vitro regeneration system, a prerequisite for genetic transformation application, requires the establishment of optimal conditions for seeds germination and plantlets development. Three types of seeds were inoculated on different basal media devoid of growth regulators. Various strengths of the medium of choice and the type and concentration of carbon source were also investigated. Responses to germination varied with the type of seed. Embryonic axis (EA) followed by seeds without coat (SWtC) germinated rapidly and expressed a high rate of germination. The growth performances of plantlets varied with the basal medium composition and the seeds type. The optimal growth performances of plants were displayed on half strength MS basal medium with SWtC and EA as source of seeds. Addition of 3% sucrose in the culture medium was more suitable for a maximum growth of plantlets derived from EA.

  6. Contrasting evolution of a satellite DNA and its ancestral IGS rDNA in Phaseolus (Fabaceae).

    PubMed

    Almeida, Cícero; Fonsêca, Artur; dos Santos, Karla Galvão Bezerra; Mosiolek, Magdalena; Pedrosa-Harand, Andrea

    2012-09-01

    CC4 is a satellite DNA from common bean (Phaseolus vulgaris L.) that is similar to its intergenic spacer (IGS) rDNA. CC4 was originally hypothesized to be an old, fast evolving satellite family that has invaded common bean rDNA. To test this hypothesis and contribute to the understanding of IGS-like satellite DNA evolution, we have investigated its distribution in the genus Phaseolus and related species. CC4 was cloned and used as probe for Southern blot and FISH experiments. CC4 was observed as an independent satellite in common bean, forming two to three major and a few minor pericentromeric clusters. In Phaseolus coccineus, CC4 was present in four major clusters, also not co-localized with the 45S rDNA sites. Remarkably, in the less related species of the genus, signals were detected co-localized with the 45S rDNA sites, but co-localization was not observed in the species where CC4 is present as an independent satellite. No signal was detected in species from related genera. Altogether, the data suggest that CC4 has originated from the IGS rDNA in the P. vulgaris-P. coccineus lineage and has evolved slower than the IGS rDNA from this lineage. PMID:23050694

  7. Effects of Millettia macrophylla (Fabaceae) extracts on estrogen target organs of female wistar rat.

    PubMed

    Zingue, Stéphane; Njamen, Dieudonné; Tchoumtchoua, Job; Halabalaki, Maria; Simpson, Evan; Clyne, Colin; Magne Nde, Chantal Beatrice

    2013-01-01

    The present study aims to determine the estrogenicity of Millettia macrophylla, a Cameroonian medicinal plant, in ovariectomized rats and to investigate the underlying mechanisms, in order to justify scientifically its traditional use. To accomplish this objective, we used dichloromethane (DCM) and methanol (MeOH) extracts of the stem bark of M. macrophylla. In the cell culture based assay, the MeOH extract significantly transactivated estrogen receptor α (ERα) and estrogen receptor β (ERβ); in addition, the estrogen-like effects of both, DCM and MeOH extracts, could be inhibited in vitro by the pure ER antagonist ICI 182,780, indicating that these effects were primarily mediated through ERs. In animal experiments, both DCM and MeOH extracts significantly increased the uterine and vaginal epithelial heights in the 3-day treatment assay, while only the MeOH extract exhibited such effects in the sub-chronic treatment regimen. Furthermore, the MeOH extract significantly decreased fasting serum triglycerides, total cholesterol levels and artherogenic risk in the sub-chronic treatment. These results indicate that M. macrophylla extracts have estrogen-like effects supporting their traditional use in Cameroon to alleviate some menopausal problems (See graphical abstract in Supplementary Fig. 1, available in the online version only). PMID:24077107

  8. Comparative genetic analysis of trichome-less and normal pod genotypes of Mucuna pruriens (Fabaceae).

    PubMed

    Dhawan, S S; Rai, G K; Darokar, M P; Lal, R K; Misra, H O; Khanuja, S P S

    2011-01-01

    Velvet bean (Mucuna pruriens) seeds contain the catecholic amino acid L-DoPA (L-3,4-dihydroxyphenylalanine), which is a neurotransmitter precursor and used for the treatment of Parkinson's disease and mental disorders. The great demand for L-DoPA is largely met by the pharmaceutical industry through extraction of the compound from wild populations of this plant; commercial exploitation of this compound is hampered because of its limited availability. The trichomes present on the pods can cause severe itching, blisters and dermatitis, discouraging cultivation. We screened genetic stocks of velvet bean for the trichome-less trait, along with high seed yield and L-DoPA content. The highest yielding trichome-less elite strain was selected and indentified on the basis of a PCR-based DNA fingerprinting method (RAPD), using deca-nucleotide primers. A genetic similarity index matrix was obtained through multivariant analysis using Nei and Li's coefficient. The similarity coefficients were used to generate a tree for cluster analysis using the UPGMA method. Analysis of amplification spectra of 408 bands obtained with 56 primers allowed us to distinguish a trichome-less elite strain of M. pruriens. PMID:21968621

  9. Lotus alianus, a new species from Cabo Verde and nomeenclatural notes on Lotus section Pedrosia (Fabaceae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lotus alianus J.H. Kirkbr., sp. nov., is described and illustrated. It is a rare endemic species from the Republic of Cape Verde, and is found in dry habitats on just two islands, Ilhas de Santo Antao and Sao Vicente. In addition, two species names are synonymized with L. creticus L., and a lectotyp...

  10. Nonlinear Structural Analysis

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Nonlinear structural analysis techniques for engine structures and components are addressed. The finite element method and boundary element method are discussed in terms of stress and structural analyses of shells, plates, and laminates.

  11. Variably porous structures

    SciTech Connect

    Braun, Paul V.; Yu, Xindi

    2011-01-18

    A method of making a monolithic porous structure, comprises electrodepositing a material on a template; removing the template from the material to form a monolithic porous structure comprising the material; and electropolishing the monolithic porous structure.

  12. Intelligent adaptive structures

    NASA Technical Reports Server (NTRS)

    Wada, Ben K.

    1990-01-01

    'Intelligent Adaptive Structures' (IAS) refers to structural systems whose geometric and intrinsic structural characteristics can be automatically changed to meet mission requirements with changing operational scenarios. An IAS is composed of actuators, sensors, and a control logic; these are integrated in a distributed fashion within the elements of the structure. The IAS concepts thus far developed for space antennas and other precision structures should be applicable to civil, marine, automotive, and aeronautical structural systems.

  13. Protein structure mining using a structural alphabet.

    PubMed

    Tyagi, M; de Brevern, A G; Srinivasan, N; Offmann, B

    2008-05-01

    We present a comprehensive evaluation of a new structure mining method called PB-ALIGN. It is based on the encoding of protein structure as 1D sequence of a combination of 16 short structural motifs or protein blocks (PBs). PBs are short motifs capable of representing most of the local structural features of a protein backbone. Using derived PB substitution matrix and simple dynamic programming algorithm, PB sequences are aligned the same way amino acid sequences to yield structure alignment. PBs are short motifs capable of representing most of the local structural features of a protein backbone. Alignment of these local features as sequence of symbols enables fast detection of structural similarities between two proteins. Ability of the method to characterize and align regions beyond regular secondary structures, for example, N and C caps of helix and loops connecting regular structures, puts it a step ahead of existing methods, which strongly rely on secondary structure elements. PB-ALIGN achieved efficiency of 85% in extracting true fold from a large database of 7259 SCOP domains and was successful in 82% cases to identify true super-family members. On comparison to 13 existing structure comparison/mining methods, PB-ALIGN emerged as the best on general ability test dataset and was at par with methods like YAKUSA and CE on nontrivial test dataset. Furthermore, the proposed method performed well when compared to flexible structure alignment method like FATCAT and outperforms in processing speed (less than 45 s per database scan). This work also establishes a reliable cut-off value for the demarcation of similar folds. It finally shows that global alignment scores of unrelated structures using PBs follow an extreme value distribution. PB-ALIGN is freely available on web server called Protein Block Expert (PBE) at http://bioinformatics.univ-reunion.fr/PBE/. PMID:18004784

  14. Describing Cognitive Structure.

    ERIC Educational Resources Information Center

    White, Richard T.

    This paper discusses questions pertinent to a definition of cognitive structure as the knowledge one possesses and the manner in which it is arranged, and considers how to select or devise methods of describing cognitive structure. The main purpose in describing cognitive structure is to see whether differences in memory (or cognitive structure)…

  15. Teaching Structured Fortran without Structured Extensions.

    ERIC Educational Resources Information Center

    Worland, Peter B.

    Six control structures are used in teaching a college Fortran programing course: (1) simple sequences of instruction without any control statement, (2) IF-THEN selection, (3) IF-THEN-ELSE selection, (4) definite loop, (5) indefinite loop, and (6) generalized IF-THEN-ELSE case structure. Outlines, instead of flowcharts, are employed for algorithm…

  16. Structural system identification: Structural dynamics model validation

    SciTech Connect

    Red-Horse, J.R.

    1997-04-01

    Structural system identification is concerned with the development of systematic procedures and tools for developing predictive analytical models based on a physical structure`s dynamic response characteristics. It is a multidisciplinary process that involves the ability (1) to define high fidelity physics-based analysis models, (2) to acquire accurate test-derived information for physical specimens using diagnostic experiments, (3) to validate the numerical simulation model by reconciling differences that inevitably exist between the analysis model and the experimental data, and (4) to quantify uncertainties in the final system models and subsequent numerical simulations. The goal of this project was to develop structural system identification techniques and software suitable for both research and production applications in code and model validation.

  17. Structural health monitoring for ship structures

    SciTech Connect

    Farrar, Charles; Park, Gyuhae; Angel, Marian; Bement, Matthew; Salvino, Liming

    2009-01-01

    Currently the Office of Naval Research is supporting the development of structural health monitoring (SHM) technology for U.S. Navy ship structures. This application is particularly challenging because of the physical size of these structures, the widely varying and often extreme operational and environmental conditions associated with these ships missions, lack of data from known damage conditions, limited sensing that was not designed specifically for SHM, and the management of the vast amounts of data that can be collected during a mission. This paper will first define a statistical pattern recognition paradigm for SHM by describing the four steps of (1) Operational Evaluation, (2) Data Acquisition, (3) Feature Extraction, and (4) Statistical Classification of Features as they apply to ship structures. Note that inherent in the last three steps of this process are additional tasks of data cleansing, compression, normalization and fusion. The presentation will discuss ship structure SHM challenges in the context of applying various SHM approaches to sea trials data measured on an aluminum multi-hull high-speed ship, the HSV-2 Swift. To conclude, the paper will discuss several outstanding issues that need to be addressed before SHM can make the transition from a research topic to actual field applications on ship structures and suggest approaches for addressing these issues.

  18. Structural design methodology for large space structures

    NASA Astrophysics Data System (ADS)

    Dornsife, Ralph J.

    1992-02-01

    The Department of Defense requires research and development in designing, fabricating, deploying, and maintaining large space structures (LSS) in support of Army and Strategic Defense Initiative military objectives. Because of their large size, extreme flexibility, and the unique loading conditions in the space environment, LSS will present engineers with problems unlike those encountered in designing conventional civil engineering or aerospace structures. LSS will require sophisticated passive damping and active control systems in order to meet stringent mission requirements. These structures must also be optimally designed to minimize high launch costs. This report outlines a methodology for the structural design of LSS. It includes a definition of mission requirements, structural modeling and analysis, passive damping and active control system design, ground-based testing, payload integration, on-orbit system verification, and on-orbit assessment of structural damage. In support of this methodology, analyses of candidate LSS truss configurations are presented, and an algorithm correlating ground-based test behavior to expected microgravity behavior is developed.

  19. Structural design methodology for large space structures

    NASA Astrophysics Data System (ADS)

    Dornsife, Ralph J.

    The Department of Defense requires research and development in designing, fabricating, deploying, and maintaining large space structures (LSS) in support of Army and Strategic Defense Initiative military objectives. Because of their large size, extreme flexibility, and the unique loading conditions in the space environment, LSS will present engineers with problems unlike those encountered in designing conventional civil engineering or aerospace structures. LSS will require sophisticated passive damping and active control systems in order to meet stringent mission requirements. These structures must also be optimally designed to minimize high launch costs. This report outlines a methodology for the structural design of LSS. It includes a definition of mission requirements, structural modeling and analysis, passive damping and active control system design, ground-based testing, payload integration, on-orbit system verification, and on-orbit assessment of structural damage. In support of this methodology, analyses of candidate LSS truss configurations are presented, and an algorithm correlating ground-based test behavior to expected microgravity behavior is developed.

  20. Lightweight Materials & Structures

    NASA Video Gallery

    The Lightweight Materials and Structures (LMS) project will mature high-payoff structures and materials technologies that have direct application to NASA’s future space exploration needs.One of the...

  1. Reinforced structural plastics

    NASA Technical Reports Server (NTRS)

    Lubowitz, H. R.; Kendrick, W. P.; Jones, J. F.; Thorpe, R. S.; Burns, E. A. (Inventor)

    1972-01-01

    Reinforced polyimide structures are described. Reinforcing materials are impregnated with a suspension of polyimide prepolymer and bonded together by heat and pressure to form a cured, hard-reinforced, polyimide structure.

  2. Lessons from Structural Genomics*

    PubMed Central

    Terwilliger, Thomas C.; Stuart, David; Yokoyama, Shigeyuki

    2010-01-01

    A decade of structural genomics, the large-scale determination of protein structures, has generated a wealth of data and many important lessons for structural biology and for future large-scale projects. These lessons include a confirmation that it is possible to construct large-scale facilities that can determine the structures of a hundred or more proteins per year, that these structures can be of high quality, and that these structures can have an important impact. Technology development has played a critical role in structural genomics, the difficulties at each step of determining a structure of a particular protein can be quantified, and validation of technologies is nearly as important as the technologies themselves. Finally, rapid deposition of data in public databases has increased the impact and usefulness of the data and international cooperation has advanced the field and improved data sharing. PMID:19416074

  3. Space Structure Development

    NASA Technical Reports Server (NTRS)

    Smith, Thomas

    2015-01-01

    The duration of my Summer 2015 Internship Tour at NASA's Johnson Space Center was spent working in the Structural Engineering Division's Structures Branch. One of the two main roles of the Structures Branch, ES2, is to ensure the structural integrity of spacecraft vehicles and the structural subsystems needed to support those vehicles. The other main objective of this branch is to develop the lightweight structures that are necessary to take humans beyond Low-Earth Orbit. Within ES2, my four projects involved inflatable space structure air bladder material testing; thermal and impact material testing for spacecraft windows; structural analysis on a joint used in the Boeing CST-100 airbag system; and an additive manufacturing design project.

  4. Representing Substantive Structures.

    ERIC Educational Resources Information Center

    Finley, Fred N.; Stewart, James

    1982-01-01

    Discusses the meaning of Schwab's "substantive structures" of a discipline in terms of science philosophy. Presents three techniques for representing substantive structures and discusses some of their uses in science education research. (SK)

  5. Structural Engineering: Overview

    NASA Technical Reports Server (NTRS)

    Castro, Edgar

    2011-01-01

    This slide presentation presents the work of the Structural Engineering Division of the Engineering Directorate. The work includes: providing technical expertise and leadership for the development, evaluation, and operation of structural, mechanical, and thermal spaceflight systems.

  6. Structural materials and components

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Lee, Raymond (Inventor)

    1982-01-01

    High density structural (blocking) materials composed of a polyimide filled with glass microballoons and methods for making such materials. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

  7. Structural materials and components

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Lee, Raymond (Inventor)

    1982-01-01

    High density structural (blocking) materials composed of a polyimide filled with glass microballoons. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

  8. Structural materials and components

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Lee, Raymond (Inventor)

    1983-01-01

    High density structural (blocking) materials composed of a polyimide filled with glass microballoons. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

  9. Neutron reflecting supermirror structure

    DOEpatents

    Wood, J.L.

    1992-12-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. 2 figs.

  10. Synchronously Deployable Truss Structures

    NASA Technical Reports Server (NTRS)

    Rhodes, M. D.; Hedgepeth, J. M.

    1986-01-01

    Structure lightweight, readily deployed, and has reliable joints. New truss concept, designated as "pac truss," developed. Features easy deployment without need for complex mechanisms. Structures of this type deployed in free flight by controlled release of stored energy in torsional springs at selected hinges located throughout structure. Double-folding technique used in beam model applicable to flat planar trusses, allowing structures of large expanse to fold into compact packages and be deployed for space-platform applications.

  11. Neutron reflecting supermirror structure

    DOEpatents

    Wood, James L.

    1992-01-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources.

  12. Optimization of composite structures

    NASA Technical Reports Server (NTRS)

    Stroud, W. J.

    1982-01-01

    Structural optimization is introduced and examples which illustrate potential problems associated with optimized structures are presented. Optimized structures may have very low load carrying ability for an off design condition. They tend to have multiple modes of failure occurring simultaneously and can, therefore, be sensitive to imperfections. Because composite materials provide more design variables than do metals, they allow for more refined tailoring and more extensive optimization. As a result, optimized composite structures can be especially susceptible to these problems.

  13. Endjoints For Structural Elements

    NASA Technical Reports Server (NTRS)

    Bush, Harold G.; Mikulas, Martin M.; Wallsom, Richard E.

    1989-01-01

    Endjoint and connecting-node system designed for use in erection of frames. System structurally sound and simple to operate. All nodes and struts interchangeable. Nodes and struts attach to form cubic cell structures to produce beams, platforms, towers, or combinations of these. Design suitable for use in construction of space structures and such terrestrial skeletal frameworks as antenna-reflector supports, roof structures for large buildings, lookout towers, radio-transmitter towers, powerline pylons, and scaffolds.

  14. Vitrified underground structures

    DOEpatents

    Murphy, Mark T.; Buelt, James L.; Stottlemyre, James A.; Tixier, Jr., John S.

    1992-01-01

    A method of making vitrified underground structures in which 1) the vitrification process is started underground, and 2) a thickness dimension is controlled to produce substantially planar vertical and horizontal vitrified underground structures. Structures may be placed around a contaminated waste site to isolate the site or may be used as aquifer dikes.

  15. HIV Structural Database

    National Institute of Standards and Technology Data Gateway

    SRD 102 HIV Structural Database (Web, free access)   The HIV Protease Structural Database is an archive of experimentally determined 3-D structures of Human Immunodeficiency Virus 1 (HIV-1), Human Immunodeficiency Virus 2 (HIV-2) and Simian Immunodeficiency Virus (SIV) Proteases and their complexes with inhibitors or products of substrate cleavage.

  16. Programing Structural Synthesis System

    NASA Technical Reports Server (NTRS)

    Rogers, James L., Jr.

    1986-01-01

    Program aids research in analysis and optimization. Programing Structural Synthesis System (PROSSS2) developed to provide structural-synthesis capability by combining access to SPAR with CONMIN program and set of interface procedures. SPAR is large general-purpose finite-element structural-analysis program, and CONMIN is large general-purpose optimization program. PROSSS2 written in FORTRAN IV for batch execution.

  17. Building safer structures

    USGS Publications Warehouse

    Celebi, Mehmet; Page, Robert A.; Seekins, Linda

    1995-01-01

    In this century, major earthquakes in the United States have damaged or destroyed numerous buildings, bridges, and other structures. By monitoring how structures respond to earthquakes and applying the knowledge gained, scientists and engineers are improving the ability of structures to survive major earthquakes. Many lives and millions of dollars have already been saved by this ongoing research.

  18. Organizational Knowledge Management Structure

    ERIC Educational Resources Information Center

    Walczak, Steven

    2005-01-01

    Purpose: To propose and evaluate a novel management structure that encourages knowledge sharing across an organization. Design/methodology/approach: The extant literature on the impact of organizational culture and its link to management structure is examined and used to develop a new knowledge sharing management structure. Roadblocks to…

  19. Catalytic distillation structure

    DOEpatents

    Smith, Jr., Lawrence A.

    1984-01-01

    Catalytic distillation structure for use in reaction distillation columns, a providing reaction sites and distillation structure and consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and being present with the catalyst component in an amount such that the catalytic distillation structure consist of at least 10 volume % open space.

  20. Structural Ceramics Database

    National Institute of Standards and Technology Data Gateway

    SRD 30 NIST Structural Ceramics Database (Web, free access)   The NIST Structural Ceramics Database (WebSCD) provides evaluated materials property data for a wide range of advanced ceramics known variously as structural ceramics, engineering ceramics, and fine ceramics.

  1. The Structures of Life

    ERIC Educational Resources Information Center

    National Institute of General Medical Sciences (NIGMS), 2007

    2007-01-01

    This booklet reveals how structural biology provides insight into health and disease and is useful in developing new medications. It contains a general introduction to proteins, coverage of the techniques used to determine protein structures, and a chapter on structure-based drug design. The booklet features "Student Snapshots," designed to…

  2. Weatherizing a Structure.

    ERIC Educational Resources Information Center

    Metz, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with weatherizing a structure. Its objective is for the student to be able to analyze factors related to specific structures that indicate need for weatherizing activities and to determine steps to correct defects in structures that…

  3. Structural Enhancement of Learning

    ERIC Educational Resources Information Center

    Trumpower, David L.; Goldsmith, Timothy E.

    2004-01-01

    Structural learning aids, such as interactive overviews (IOs), have previously been shown to facilitate text comprehension and recall. In this study, we examined the effects of structural aids on learners' structural knowledge and their performance on a procedural transfer task. In Experiment 1, 90 college students were presented definitions of…

  4. Structured FORTRAN Preprocessor

    NASA Technical Reports Server (NTRS)

    Flynn, J. A.; Lawson, C. L.; Van Snyder, W.; Tsitsivas, H. N.

    1985-01-01

    SFTRAN3 supports structured programing in FORTRAN environment. Language intended particularly to support two aspects of structured programing -- nestable single-entry control structures and modularization and top-down organization of code. Code designed and written using these SFTRAN3 facilities have fewer initial errors, easier to understand and less expensive to maintain and modify.

  5. Hypermedia 1990 structured Hypertext tutorial

    NASA Technical Reports Server (NTRS)

    Johnson, J. Scott

    1990-01-01

    Hypermedia 1990 structured Hypertext tutorial is presented in the form of view-graphs. The following subject areas are covered: structured hypertext; analyzing hypertext documents for structure; designing structured hypertext documents; creating structured hypertext applications; structuring service and repair documents; maintaining structured hypertext documents; and structured hypertext conclusion.

  6. Modelling ionospheric density structures

    NASA Technical Reports Server (NTRS)

    Schunk, R. W.; Sojka, J. J.

    1989-01-01

    Large-scale density structures are a common feature in the high-latitude ionsphere. The structures were observed in the dayside cusp, polar cap, and nocturnal auroral region over a range of altitudes, including the E-region, F-region and topside ionosphere. The origins, lifetimes and transport characteristics of large-scale density structures were studied with the aid of a three-dimensional, time-dependent ionospheric model. Blob creation due to particle precipitation, the effect that structured electric fields have on the ionosphere, and the lifetimes and transport characteristics of density structures for different seasonal, solar cycle, and interplanetary magnetic field (IMF) conditions were studied. The main conclusions drawn are: (1) the observed precipitation energy fluxes are sufficient for blob creation if the plasma is exposed to the precipitation for 5 to 10 minutes; (2) structured electric fields produce structured electron densities, ion temperatures, and ion composition; (3) the lifetime of an F-region density structure depends on several factors, including the initial location where it was formed, the magnitude of the perturbation, season, solar cycle and IMF; and (4) depending on the IMF, horizontal plasma convection can cause an initial structure to break up into multiple structures of various sizes, remain as a single distorted structure, or become stretched into elongated segments.

  7. Materials and structures

    NASA Technical Reports Server (NTRS)

    Saito, Theodore T.; Langenbeck, Sharon L.; Al-Jamily, Ghanim; Arnold, Joe; Barbee, Troy; Coulter, Dan; Dolgin, Ben; Fichter, Buck; George, Patricia; Gorenstein, Paul

    1992-01-01

    Materials and structures technology covers a wide range of technical areas. Some of the most pertinent issues for the Astrotech 21 missions include dimensionally stable structural materials, advanced composites, dielectric coatings, optical metallic coatings for low scattered light applications, low scattered light surfaces, deployable and inflatable structures (including optical), support structures in 0-g and 1-g environments, cryogenic optics, optical blacks, contamination hardened surfaces, radiation hardened glasses and crystals, mono-metallic telescopes and instruments, and materials characterization. Some specific examples include low coefficients of thermal expansion (CTE) structures (0.01 ppm/K), lightweight thermally stable mirror materials, thermally stable optical assemblies, high reliability/accuracy (1 micron) deployable structures, and characterization of nanometer level behavior of materials/structures for interferometry concepts. Large filled-aperture concepts will require materials with CTE's of 10(exp 9) at 80 K, anti-contamination coatings, deployable and erectable structures, composite materials with CTE's less than 0.01 ppm/K and thermal hysteresis, 0.001 ppm/K. Gravitational detection systems such as LAGOS will require rigid/deployable structures, dimensionally stable components, lightweight materials with low conductivity, and high stability optics. The Materials and Structures panel addressed these issues and the relevance of the Astrotech 21 mission requirements by dividing materials and structures technology into five categories. These categories, the necessary development, and applicable mission/program development phasing are summarized. For each of these areas, technology assessments were made and development plans were defined.

  8. Materials and structures

    NASA Astrophysics Data System (ADS)

    Saito, Theodore T.; Langenbeck, Sharon L.; Al-Jamily, Ghanim; Arnold, Joe; Barbee, Troy; Coulter, Dan; Dolgin, Ben; Fichter, Buck; George, Patricia; Gorenstein, Paul

    1992-08-01

    Materials and structures technology covers a wide range of technical areas. Some of the most pertinent issues for the Astrotech 21 missions include dimensionally stable structural materials, advanced composites, dielectric coatings, optical metallic coatings for low scattered light applications, low scattered light surfaces, deployable and inflatable structures (including optical), support structures in 0-g and 1-g environments, cryogenic optics, optical blacks, contamination hardened surfaces, radiation hardened glasses and crystals, mono-metallic telescopes and instruments, and materials characterization. Some specific examples include low coefficients of thermal expansion (CTE) structures (0.01 ppm/K), lightweight thermally stable mirror materials, thermally stable optical assemblies, high reliability/accuracy (1 micron) deployable structures, and characterization of nanometer level behavior of materials/structures for interferometry concepts. Large filled-aperture concepts will require materials with CTE's of 10(exp 9) at 80 K, anti-contamination coatings, deployable and erectable structures, composite materials with CTE's less than 0.01 ppm/K and thermal hysteresis, 0.001 ppm/K. Gravitational detection systems such as LAGOS will require rigid/deployable structures, dimensionally stable components, lightweight materials with low conductivity, and high stability optics. The Materials and Structures panel addressed these issues and the relevance of the Astrotech 21 mission requirements by dividing materials and structures technology into five categories. These categories, the necessary development, and applicable mission/program development phasing are summarized. For each of these areas, technology assessments were made and development plans were defined.

  9. Computers boost structural technology

    NASA Technical Reports Server (NTRS)

    Noor, Ahmed K.; Venneri, Samuel L.

    1989-01-01

    Derived from matrix methods of structural analysis and finite element methods developed over the last three decades, computational structures technology (CST) blends computer science, numerical analysis, and approximation theory into structural analysis and synthesis. Recent significant advances in CST include stochastic-based modeling, strategies for performing large-scale structural calculations on new computing systems, and the integration of CST with other disciplinary modules for multidisciplinary analysis and design. New methodologies have been developed at NASA for integrated fluid-thermal structural analysis and integrated aerodynamic-structure-control design. The need for multiple views of data for different modules also led to the development of a number of sophisticated data-base management systems. For CST to play a role in the future development of structures technology and in the multidisciplinary design of future flight vehicles, major advances and computational tools are needed in a number of key areas.

  10. Structures of membrane proteins

    PubMed Central

    Vinothkumar, Kutti R.; Henderson, Richard

    2010-01-01

    In reviewing the structures of membrane proteins determined up to the end of 2009, we present in words and pictures the most informative examples from each family. We group the structures together according to their function and architecture to provide an overview of the major principles and variations on the most common themes. The first structures, determined 20 years ago, were those of naturally abundant proteins with limited conformational variability, and each membrane protein structure determined was a major landmark. With the advent of complete genome sequences and efficient expression systems, there has been an explosion in the rate of membrane protein structure determination, with many classes represented. New structures are published every month and more than 150 unique membrane protein structures have been determined. This review analyses the reasons for this success, discusses the challenges that still lie ahead, and presents a concise summary of the key achievements with illustrated examples selected from each class. PMID:20667175

  11. Adaptive structures in space

    NASA Technical Reports Server (NTRS)

    Wada, B. K.; Fanson, J. L.; Chen, G. S.; Kuo, C.-P.

    1990-01-01

    Future NASA missions will need large (20 to 100m) structural systems with precision position (few microns to submicron) requirements. Data are presented which indicate the technology deficiencies of previous programs and analyses in current state-of-the-art structural design approaches, analytical prediction capabilities, control of structure capabilities, and ground test technologies to meet the performance requirements of future large precision structural systems. Test results on laboratory truss structures that demonstrate static displacement control, active damping, and on-orbit system identification are described. It is shown that for large precision structures, adaptive structures provide not only a means to achieve the precision and characteristics required in space, but can also significantly alleviate the ground test requirements for flight-validating the hardware.

  12. From nuclear structure to nucleon structure

    NASA Astrophysics Data System (ADS)

    Liu, Keh-Fei

    2014-08-01

    Similarities between nuclear structure study with many-body theory approach and nucleon structure calculations with lattice QCD are pointed out. We will give an example of how to obtain the connected sea partons from a combination of the experimental data, a global fit of parton distribution functions and a lattice calculation. We also present a complete calculation of the quark and glue decomposition of the proton momentum and angular momentum in the quenched approximation. It is found that the quark orbital angular momentum constitutes about 50% of the proton spin.

  13. The ectomycorrhizal fungal community in a neotropical forest dominated by the endemic dipterocarp Pakaraimaea dipterocarpacea.

    PubMed

    Smith, Matthew E; Henkel, Terry W; Uehling, Jessie K; Fremier, Alexander K; Clarke, H David; Vilgalys, Rytas

    2013-01-01

    Ectomycorrhizal (ECM) plants and fungi can be diverse and abundant in certain tropical ecosystems. For example, the primarily paleotropical ECM plant family Dipterocarpaceae is one of the most speciose and ecologically important tree families in Southeast Asia. Pakaraimaea dipterocarpacea is one of two species of dipterocarp known from the Neotropics, and is also the only known member of the monotypic Dipterocarpaceae subfamily Pakaraimoideae. This Guiana Shield endemic is only known from the sandstone highlands of Guyana and Venezuela. Despite its unique phylogenetic position and unusual geographical distribution, the ECM fungal associations of P. dipterocarpacea are understudied throughout the tree's range. In December 2010 we sampled ECM fungi on roots of P. dipterocarpacea and the co-occurring ECM tree Dicymbe jenmanii (Fabaceae subfamily Caesalpinioideae) in the Upper Mazaruni River Basin of Guyana. Based on ITS rDNA sequencing we documented 52 ECM species from 11 independent fungal lineages. Due to the phylogenetic distance between the two host tree species, we hypothesized that P. dipterocarpacea would harbor unique ECM fungi not found on the roots of D. jenmanii. Although statistical tests suggested that several ECM fungal species did exhibit host preferences for either P. dipterocarpacea or D. jenmanii, most of the ECM fungi were multi-host generalists. We also detected several ECM fungi that have never been found in long-term studies of nearby rainforests dominated by other Dicymbe species. One particular mushroom-forming fungus appears to be unique and may represent a new ECM lineage of Agaricales that is endemic to the Neotropics. PMID:23383090

  14. The Ectomycorrhizal Fungal Community in a Neotropical Forest Dominated by the Endemic Dipterocarp Pakaraimaea dipterocarpacea

    PubMed Central

    Smith, Matthew E.; Henkel, Terry W.; Uehling, Jessie K.; Fremier, Alexander K.; Clarke, H. David; Vilgalys, Rytas

    2013-01-01

    Ectomycorrhizal (ECM) plants and fungi can be diverse and abundant in certain tropical ecosystems. For example, the primarily paleotropical ECM plant family Dipterocarpaceae is one of the most speciose and ecologically important tree families in Southeast Asia. Pakaraimaea dipterocarpacea is one of two species of dipterocarp known from the Neotropics, and is also the only known member of the monotypic Dipterocarpaceae subfamily Pakaraimoideae. This Guiana Shield endemic is only known from the sandstone highlands of Guyana and Venezuela. Despite its unique phylogenetic position and unusual geographical distribution, the ECM fungal associations of P. dipterocarpacea are understudied throughout the tree’s range. In December 2010 we sampled ECM fungi on roots of P. dipterocarpacea and the co-occurring ECM tree Dicymbe jenmanii (Fabaceae subfamily Caesalpinioideae) in the Upper Mazaruni River Basin of Guyana. Based on ITS rDNA sequencing we documented 52 ECM species from 11 independent fungal lineages. Due to the phylogenetic distance between the two host tree species, we hypothesized that P. dipterocarpacea would harbor unique ECM fungi not found on the roots of D. jenmanii. Although statistical tests suggested that several ECM fungal species did exhibit host preferences for either P. dipterocarpacea or D. jenmanii, most of the ECM fungi were multi-host generalists. We also detected several ECM fungi that have never been found in long-term studies of nearby rainforests dominated by other Dicymbe species. One particular mushroom-forming fungus appears to be unique and may represent a new ECM lineage of Agaricales that is endemic to the Neotropics. PMID:23383090

  15. The ectomycorrhizal fungal community in a neotropical forest dominated by the endemic dipterocarp Pakaraimaea dipterocarpacea.

    PubMed

    Smith, Matthew E; Henkel, Terry W; Uehling, Jessie K; Fremier, Alexander K; Clarke, H David; Vilgalys, Rytas

    2013-01-01

    Ectomycorrhizal (ECM) plants and fungi can be diverse and abundant in certain tropical ecosystems. For example, the primarily paleotropical ECM plant family Dipterocarpaceae is one of the most speciose and ecologically important tree families in Southeast Asia. Pakaraimaea dipterocarpacea is one of two species of dipterocarp known from the Neotropics, and is also the only known member of the monotypic Dipterocarpaceae subfamily Pakaraimoideae. This Guiana Shield endemic is only known from the sandstone highlands of Guyana and Venezuela. Despite its unique phylogenetic position and unusual geographical distribution, the ECM fungal associations of P. dipterocarpacea are understudied throughout the tree's range. In December 2010 we sampled ECM fungi on roots of P. dipterocarpacea and the co-occurring ECM tree Dicymbe jenmanii (Fabaceae subfamily Caesalpinioideae) in the Upper Mazaruni River Basin of Guyana. Based on ITS rDNA sequencing we documented 52 ECM species from 11 independent fungal lineages. Due to the phylogenetic distance between the two host tree species, we hypothesized that P. dipterocarpacea would harbor unique ECM fungi not found on the roots of D. jenmanii. Although statistical tests suggested that several ECM fungal species did exhibit host preferences for either P. dipterocarpacea or D. jenmanii, most of the ECM fungi were multi-host generalists. We also detected several ECM fungi that have never been found in long-term studies of nearby rainforests dominated by other Dicymbe species. One particular mushroom-forming fungus appears to be unique and may represent a new ECM lineage of Agaricales that is endemic to the Neotropics.

  16. Protein Structure Databases.

    PubMed

    Laskowski, Roman A

    2016-01-01

    Web-based protein structure databases come in a wide variety of types and levels of information content. Those having the most general interest are the various atlases that describe each experimentally determined protein structure and provide useful links, analyses, and schematic diagrams relating to its 3D structure and biological function. Also of great interest are the databases that classify 3D structures by their folds as these can reveal evolutionary relationships which may be hard to detect from sequence comparison alone. Related to these are the numerous servers that compare folds-particularly useful for newly solved structures, and especially those of unknown function. Beyond these are a vast number of databases for the more specialized user, dealing with specific families, diseases, structural features, and so on. PMID:27115626

  17. Pyramidal structures on Mars

    NASA Technical Reports Server (NTRS)

    Gipson, M., Jr.; Ablordeppey, V. K.

    1974-01-01

    Triangular and polygonal pyramid like structures have been observed on the Martian surface. Located in the east central portion of Elysium Quadrangle (MC-15), these features are visible on the Mariner 9 photographs. B frames MTVS 4205-3 DAS 07794853 and MTVS 4296-24 DAS 12985882. The structures cast triangular and polygonal shadows. Steep-sided volcanic cones and impact craters occur only a few kilometers away. The mean diameter of the triangular pyramidal structures at the base is approximately 3.0 km, and the mean diameter of the polygonal structures is approximately 6.0 km. The observed Martian structures tend to line up suggesting joint or fault control. However, they do not appear to be controlled by the visible faults. The structures appear to be either wind-faceted volcanic cones and blocks or solidified blocks which have been rotated in semiconsolidated lava.

  18. Analysis of Geological Structures

    NASA Astrophysics Data System (ADS)

    Price, Neville J.; Cosgrove, John W.

    1990-08-01

    A knowledge of structural geology is fundamental to understanding the processes by which the earth's crust has evolved. It is a subject of fundamental importance to students of geology, experienced field geologists and academic researchers as well as to petroleum and mining engineers. In contrast to many structural textbooks which dwell upon geometrical descriptions of geological structures, this book emphasises mechanical principles and the way in which they can be used to understand how and why a wide range of geological structures develop. Structures on all scales are considered but the emphasis of the book is on those that can be seen on the scale of hand specimen or outcrop. Drawing on their considerable teaching experience the authors present a coherent and lucid analysis of geological structures which will be welcomed by a wide variety of earth scientists.

  19. BOMB STABILIZING STRUCTURE

    DOEpatents

    Kelley, J.L.; Runyan, C.E.

    1963-12-10

    A stabilizinig structure capable of minimizing deviations of a falling body such as a bomb from desired trajectory is described. The structure comprises a fin or shroud arrangement of double-wedge configuration, the feeding portion being of narrow wedge shape and the after portion being of a wider wedge shape. The structure provides a force component for keeping the body on essentially desired trajectory throughout its fall. (AEC)

  20. Catalytic distillation structure

    DOEpatents

    Smith, L.A. Jr.

    1984-04-17

    Catalytic distillation structure is described for use in reaction distillation columns, and provides reaction sites and distillation structure consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and is present with the catalyst component in an amount such that the catalytic distillation structure consists of at least 10 volume % open space. 10 figs.

  1. Structures and Acoustics Division

    NASA Technical Reports Server (NTRS)

    Acquaviva, Cynthia S.

    1999-01-01

    The Structures and Acoustics Division of NASA Glenn Research Center is an international leader in rotating structures, mechanical components, fatigue and fracture, and structural aeroacoustics. Included are disciplines related to life prediction and reliability, nondestructive evaluation, and mechanical drive systems. Reported are a synopsis of the work and accomplishments reported by the Division during the 1996 calendar year. A bibliography containing 42 citations is provided.

  2. Structures and Acoustics Division

    NASA Technical Reports Server (NTRS)

    Acquaviva, Cynthia S.

    2001-01-01

    The Structures and Acoustics Division of the NASA Glenn Research Center is an international leader in rotating structures, mechanical components, fatigue and fracture, and structural aeroacoustics. Included in this report are disciplines related to life prediction and reliability, nondestructive evaluation, and mechanical drive systems. Reported is a synopsis of the work and accomplishments completed by the Division during the 1997, 1998, and 1999 calendar years. A bibliography containing 93 citations is provided.

  3. Photon structure function

    SciTech Connect

    Bardeen, W.A.

    1980-11-01

    Theoretical understanding of the photon structure function is reviewed. As an illustration of the pointlike component, the parton model is briefly discussed. However, the systematic study of the photon structure function is presented through the framework of the operator product expansion. Perturbative QCD is used as the theoretical basis for the calculation of leading contributions to the operator product expansion. The influence of higher order QCD effects on these results is discussed. Recent results for the polarized structure functions are discussed.

  4. Structural assembly in space

    NASA Technical Reports Server (NTRS)

    Stokes, J. W.; Pruett, E. C.

    1980-01-01

    A cost algorithm for predicting assembly costs for large space structures is given. Assembly scenarios are summarized which describe the erection, deployment, and fabrication tasks for five large space structures. The major activities that impact total costs for structure assembly from launch through deployment and assembly to scientific instrument installation and checkout are described. Individual cost elements such as assembly fixtures, handrails, or remote minipulators are also presented.

  5. [Hospital organizational structure].

    PubMed

    Bittar, O J

    1994-01-01

    The basic point for an Institution to work is the existence of a definite organizational structure that puts together similar areas allowing decisions and the operationalization of different tasks. Knowledge and analysis of structures of private and public hospitals and a bibliography review about the issue is the purpose of this paper. Suggestions are given about the elaboration of small structures and the utilization of matrix management in order to accomplish the hospitals objectives.

  6. Space station structures development

    NASA Technical Reports Server (NTRS)

    Teller, V. B.

    1986-01-01

    A study of three interrelated tasks focusing on deployable Space Station truss structures is discussed. Task 1, the development of an alternate deployment system for linear truss, resulted in the preliminary design of an in-space reloadable linear motor deployer. Task 2, advanced composites deployable truss development, resulted in the testing and evaluation of composite materials for struts used in a deployable linear truss. Task 3, assembly of structures in space/erectable structures, resulted in the preliminary design of Space Station pressurized module support structures. An independent, redundant support system was developed for the common United States modules.

  7. Structural building response review

    SciTech Connect

    Not Available

    1980-01-15

    The integrity of a nuclear power plant during a postulated seismic event is required to protect the public against radiation. Therefore, a detailed set of seismic analyses of various structures and equipment is performed while designing a nuclear power plant. This report describes the structural response analysis method, including the structural model, soil-structure interaction as it relates to structural models, methods for seismic structural analysis, numerical integration methods, methods for non-seismic response analysis approaches for various response combinations, structural damping values, nonlinear response, uncertainties in structural properties, and structural response analysis using random properties. The report describes the state-of-the-art in these areas for nuclear power plants. It also details the past studies made at Sargent and Lundy to evaluate different alternatives and the conclusions reached for the specific purposes that those studies were intended. These results were incorporated here because they fall into the general scope of this report. The scope of the present task does not include performing new calculations.

  8. Integrated structural health monitoring.

    SciTech Connect

    Farrar, C. R.

    2001-01-01

    Structural health monitoring is the implementation of a damage detection strategy for aerospace, civil and mechanical engineering infrastructure. Typical damage experienced by this infrastructure might be the development of fatigue cracks, degradation of structural connections, or bearing wear in rotating machinery. The goal of the research effort reported herein is to develop a robust and cost-effective structural health monitoring solution by integrating and extending technologies from various engineering and information technology disciplines. It is the authors opinion that all structural health monitoring systems must be application specific. Therefore, a specific application, monitoring welded moment resisting steel frame connections in structures subjected to seismic excitation, is described along with the motivation for choosing this application. The structural health monitoring solution for this application will integrate structural dynamics, wireless data acquisition, local actuation, micro-electromechanical systems (MEMS) technology, and statistical pattern recognition algorithms. The proposed system is based on an assessment of the deficiencies associated with many current structural health monitoring technologies including past efforts by the authors. This paper provides an example of the integrated approach to structural health monitoring being undertaken at Los Alamos National Laboratory and summarizes progress to date on various aspects of the technology development.

  9. Flexible Volumetric Structure

    NASA Technical Reports Server (NTRS)

    Cagle, Christopher M. (Inventor); Schlecht, Robin W. (Inventor)

    2014-01-01

    A flexible volumetric structure has a first spring that defines a three-dimensional volume and includes a serpentine structure elongatable and compressible along a length thereof. A second spring is coupled to at least one outboard edge region of the first spring. The second spring is a sheet-like structure capable of elongation along an in-plane dimension thereof. The second spring is oriented such that its in-plane dimension is aligned with the length of the first spring's serpentine structure.

  10. Structures and stochastic methods

    SciTech Connect

    Cakmak, A.S.

    1987-01-01

    Studies and research on structures and stochastic methods in the soil dynamics and earthquake engineering filed are covered in this book. The first section is on structures and includes studies on bridges, loaded tanks, sliding structures and wood-framed houses. The second section covers dams, retaining walls and slopes. The third section on underground structures covers pipelines, water supply, fire loss, buried lifeline, and underground transmission lines. The final section is on stochastic methods and includes applications in earthquake response spectra, lifeline aqueduct systems, and various other areas.

  11. Deployable Soft Composite Structures.

    PubMed

    Wang, Wei; Rodrigue, Hugo; Ahn, Sung-Hoon

    2016-01-01

    Deployable structure composed of smart materials based actuators can reconcile its inherently conflicting requirements of low mass, good shape adaptability, and high load-bearing capability. This work describes the fabrication of deployable structures using smart soft composite actuators combining a soft matrix with variable stiffness properties and hinge-like movement through a rigid skeleton. The hinge actuator has the advantage of being simple to fabricate, inexpensive, lightweight and simple to actuate. This basic actuator can then be used to form modules capable of different types of deformations, which can then be assembled into deployable structures. The design of deployable structures is based on three principles: design of basic hinge actuators, assembly of modules and assembly of modules into large-scale deployable structures. Various deployable structures such as a segmented triangular mast, a planar structure comprised of single-loop hexagonal modules and a ring structure comprised of single-loop quadrilateral modules were designed and fabricated to verify this approach. Finally, a prototype for a deployable mirror was developed by attaching a foldable reflective membrane to the designed ring structure and its functionality was tested by using it to reflect sunlight onto to a small-scale solar panel. PMID:26892762

  12. Neutron reflecting supermirror structure

    DOEpatents

    Wood, James L.

    1992-01-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. One layer of each set of bilayers consist of titanium, and the second layer of each set of bilayers consist of an alloy of nickel with carbon interstitially present in the nickel alloy.

  13. Deployable Soft Composite Structures

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Rodrigue, Hugo; Ahn, Sung-Hoon

    2016-02-01

    Deployable structure composed of smart materials based actuators can reconcile its inherently conflicting requirements of low mass, good shape adaptability, and high load-bearing capability. This work describes the fabrication of deployable structures using smart soft composite actuators combining a soft matrix with variable stiffness properties and hinge-like movement through a rigid skeleton. The hinge actuator has the advantage of being simple to fabricate, inexpensive, lightweight and simple to actuate. This basic actuator can then be used to form modules capable of different types of deformations, which can then be assembled into deployable structures. The design of deployable structures is based on three principles: design of basic hinge actuators, assembly of modules and assembly of modules into large-scale deployable structures. Various deployable structures such as a segmented triangular mast, a planar structure comprised of single-loop hexagonal modules and a ring structure comprised of single-loop quadrilateral modules were designed and fabricated to verify this approach. Finally, a prototype for a deployable mirror was developed by attaching a foldable reflective membrane to the designed ring structure and its functionality was tested by using it to reflect sunlight onto to a small-scale solar panel.

  14. Deployable Soft Composite Structures

    PubMed Central

    Wang, Wei; Rodrigue, Hugo; Ahn, Sung-Hoon

    2016-01-01

    Deployable structure composed of smart materials based actuators can reconcile its inherently conflicting requirements of low mass, good shape adaptability, and high load-bearing capability. This work describes the fabrication of deployable structures using smart soft composite actuators combining a soft matrix with variable stiffness properties and hinge-like movement through a rigid skeleton. The hinge actuator has the advantage of being simple to fabricate, inexpensive, lightweight and simple to actuate. This basic actuator can then be used to form modules capable of different types of deformations, which can then be assembled into deployable structures. The design of deployable structures is based on three principles: design of basic hinge actuators, assembly of modules and assembly of modules into large-scale deployable structures. Various deployable structures such as a segmented triangular mast, a planar structure comprised of single-loop hexagonal modules and a ring structure comprised of single-loop quadrilateral modules were designed and fabricated to verify this approach. Finally, a prototype for a deployable mirror was developed by attaching a foldable reflective membrane to the designed ring structure and its functionality was tested by using it to reflect sunlight onto to a small-scale solar panel. PMID:26892762

  15. Deployable Soft Composite Structures.

    PubMed

    Wang, Wei; Rodrigue, Hugo; Ahn, Sung-Hoon

    2016-02-19

    Deployable structure composed of smart materials based actuators can reconcile its inherently conflicting requirements of low mass, good shape adaptability, and high load-bearing capability. This work describes the fabrication of deployable structures using smart soft composite actuators combining a soft matrix with variable stiffness properties and hinge-like movement through a rigid skeleton. The hinge actuator has the advantage of being simple to fabricate, inexpensive, lightweight and simple to actuate. This basic actuator can then be used to form modules capable of different types of deformations, which can then be assembled into deployable structures. The design of deployable structures is based on three principles: design of basic hinge actuators, assembly of modules and assembly of modules into large-scale deployable structures. Various deployable structures such as a segmented triangular mast, a planar structure comprised of single-loop hexagonal modules and a ring structure comprised of single-loop quadrilateral modules were designed and fabricated to verify this approach. Finally, a prototype for a deployable mirror was developed by attaching a foldable reflective membrane to the designed ring structure and its functionality was tested by using it to reflect sunlight onto to a small-scale solar panel.

  16. Inflatable Column Structure

    NASA Technical Reports Server (NTRS)

    Hedgepeth, J. M.

    1985-01-01

    Lightweight structural member easy to store. Billowing between circumferential loops of fiber inflated column becomes series of cells. Each fiber subjected to same tension along entire length (though tension is different in different fibers). Member is called "isotensoid" column. Serves as jack for automobiles or structures during repairs. Also used as support for temporary bleachers or swimming pools.

  17. Multidimensional period doubling structures.

    PubMed

    Lee, Jeong Yup; Flom, Dvir; Ben-Abraham, Shelomo I

    2016-05-01

    This paper develops the formalism necessary to generalize the period doubling sequence to arbitrary dimension by straightforward extension of the substitution and recursion rules. It is shown that the period doubling structures of arbitrary dimension are pure point diffractive. The symmetries of the structures are pointed out. PMID:27126116

  18. Organisational Structure & Change

    ERIC Educational Resources Information Center

    National Centre for Vocational Education Research (NCVER), 2006

    2006-01-01

    Structural change is seen as a way to meet the challenges of the future that face many organisations. While some writers agree that broad-ranging structural change may not always transform an organisation or enhance its performance, others claim that innovation will be a major source of competitive advantage to organisations, particularly when…

  19. Generalized holomorphic structures

    NASA Astrophysics Data System (ADS)

    Wang, Yicao

    2014-12-01

    We define the notion of generalized holomorphic principal bundles and establish that their associated vector bundles of holomorphic representations are generalized holomorphic vector bundles defined by M. Gualtieri. Motivated by our definition, several examples of generalized holomorphic structures are constructed. A reduction theorem of generalized holomorphic structures is also included.

  20. SOD: Framework structures

    NASA Astrophysics Data System (ADS)

    Fischer, R. X.; Baur, W. H.

    This document is part of Subvolume E `Zeolite-Type Crystal Structures and their Chemistry. Framework Type Codes RON to STI' of Volume 14 `Microporous and other Framework Materials with Zeolite-Type Structures' of Landolt-Börnstein Group IV `Physical Chemistry'.

  1. The Structure of Reciprocity

    ERIC Educational Resources Information Center

    Molm, Linda D.

    2010-01-01

    Reciprocity is one of the defining features of social exchange and social life, yet exchange theorists have tended to take it for granted. Drawing on work from a decade-long theoretical research program, I argue that reciprocity is structured and variable across different forms of exchange, that these variations in the structure of reciprocity…

  2. The Cambridge Structural Database.

    PubMed

    Groom, Colin R; Bruno, Ian J; Lightfoot, Matthew P; Ward, Suzanna C

    2016-04-01

    The Cambridge Structural Database (CSD) contains a complete record of all published organic and metal-organic small-molecule crystal structures. The database has been in operation for over 50 years and continues to be the primary means of sharing structural chemistry data and knowledge across disciplines. As well as structures that are made public to support scientific articles, it includes many structures published directly as CSD Communications. All structures are processed both computationally and by expert structural chemistry editors prior to entering the database. A key component of this processing is the reliable association of the chemical identity of the structure studied with the experimental data. This important step helps ensure that data is widely discoverable and readily reusable. Content is further enriched through selective inclusion of additional experimental data. Entries are available to anyone through free CSD community web services. Linking services developed and maintained by the CCDC, combined with the use of standard identifiers, facilitate discovery from other resources. Data can also be accessed through CCDC and third party software applications and through an application programming interface.

  3. Structure of Skeletal Muscle

    MedlinePlus

    ... Cells, Tissues, & Membranes Cell Structure & Function Cell Structure Cell Function Body Tissues Epithelial Tissue Connective Tissue Muscle Tissue ... nerves. This is directly related to the primary function of skeletal muscle, ... an impulse from a nerve cell. Generally, an artery and at least one vein ...

  4. Piaget's Structural Developmental Psychology.

    ERIC Educational Resources Information Center

    Broughton, John M.

    1981-01-01

    Piaget's theory is identified as a branch of structuralism concerned with the concept of truth, in distinction from French structuralism, which is focused on meaning. The two branches are compared and contrasted, and relations between logic and language are explored. Similarities and differences in the theories of Piaget, Levi-Strauss, and Chomsky…

  5. The Changing Family Structure.

    ERIC Educational Resources Information Center

    Bernard van Leer Foundation Newsletter, 1993

    1993-01-01

    This newsletter issue contains feature articles and short reports on how and why family structures are undergoing substantial change in many parts of the world. These articles include: (1) "The Changing Family Structure," a review of how families are changing and why; (2) "Peru: Families in the Andes"; (3) "Thailand: Families of the Garbage Dump";…

  6. Solution structure of (+)-discodermolide.

    PubMed

    Smith, A B; LaMarche, M J; Falcone-Hindley, M

    2001-03-01

    [structure: see text]. The solution structure of (+)-discodermolide (1) has been determined via 1- and 2-D NMR techniques in conjunction with Monte Carlo conformational analysis. Taken together, the results demonstrate that in solution (+)-discodermolide occupies a helical conformation remarkably similar to the solid state conformation.

  7. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Loewy, R. G.; Wiberley, S. E.

    1985-01-01

    Various topics relating to composite structural materials for use in aircraft structures are discussed. The mechanical properties of high performance carbon fibers, carbon fiber-epoxy interface bonds, composite fractures, residual stress in high modulus and high strength carbon fibers, fatigue in composite materials, and the mechanical properties of polymeric matrix composite laminates are among the topics discussed.

  8. The Cambridge Structural Database

    PubMed Central

    Groom, Colin R.; Bruno, Ian J.; Lightfoot, Matthew P.; Ward, Suzanna C.

    2016-01-01

    The Cambridge Structural Database (CSD) contains a complete record of all published organic and metal–organic small-molecule crystal structures. The database has been in operation for over 50 years and continues to be the primary means of sharing structural chemistry data and knowledge across disciplines. As well as structures that are made public to support scientific articles, it includes many structures published directly as CSD Communications. All structures are processed both computationally and by expert structural chemistry editors prior to entering the database. A key component of this processing is the reliable association of the chemical identity of the structure studied with the experimental data. This important step helps ensure that data is widely discoverable and readily reusable. Content is further enriched through selective inclusion of additional experimental data. Entries are available to anyone through free CSD community web services. Linking services developed and maintained by the CCDC, combined with the use of standard identifiers, facilitate discovery from other resources. Data can also be accessed through CCDC and third party software applications and through an application programming interface. PMID:27048719

  9. Calcium silicate insulation structure

    DOEpatents

    Kollie, Thomas G.; Lauf, Robert J.

    1995-01-01

    An insulative structure including a powder-filled evacuated casing utilizes a quantity of finely divided synthetic calcium silicate having a relatively high surface area. The resultant structure-provides superior thermal insulating characteristics over a broad temperature range and is particularly well-suited as a panel for a refrigerator or freezer or the insulative barrier for a cooler or a insulated bottle.

  10. The Structures of Life.

    ERIC Educational Resources Information Center

    National Inst. of General Medical Sciences (NIH), Bethesda, MD.

    This booklet, geared toward an advanced high school or early college-level audience, explains how structural biology provides insight into health and disease and is useful in developing new medications. This publication contains a general introduction to proteins, coverage of the techniques used to determine protein structures, and a chapter on…

  11. Tapered structure construction

    DOEpatents

    Smith, Eric D.; Takata, Rosalind K.; Slocum, Alexander H.; Nayfeh, Samir A.

    2016-04-05

    Feeding stock used to form a tapered structure into a curving device such that each point on the stock undergoes rotational motion about a peak location of the tapered structure; and the stock meets a predecessor portion of stock along one or more adjacent edges.

  12. Structurally abnormal human autosomes

    SciTech Connect

    1993-12-31

    Chapter 25, discusses structurally abnormal human autosomes. This discussion includes: structurally abnormal chromosomes, chromosomal polymorphisms, pericentric inversions, paracentric inversions, deletions or partial monosomies, cri du chat (cat cry) syndrome, ring chromosomes, insertions, duplication or pure partial trisomy and mosaicism. 71 refs., 8 figs.

  13. Agricultural Structures, Volume II.

    ERIC Educational Resources Information Center

    Linhardt, Richard E.; Burhoe, Steve

    This guide to a curriculum unit in agricultural structures is designed to expand the curriculum materials available in vocational agriculture in Missouri. It and Agricultural Structures I (see note) provide reference materials to systematize the curriculum. The six units cover working with concrete (19 lessons, 2 laboratory exercises), drawing and…

  14. Space Station structures

    NASA Astrophysics Data System (ADS)

    Schneider, W.

    1985-04-01

    A brief overview of some structural results that came from space station skunk works is presented. Detailed drawings of the pressurized modules, and primary truss structures such as deployable single fold beams, erectable beams and deployable double folds are given. Typical truss attachment devices and deployable backup procedures are also given.

  15. Space Station structures

    NASA Technical Reports Server (NTRS)

    Schneider, W.

    1985-01-01

    A brief overview of some structural results that came from space station skunk works is presented. Detailed drawings of the pressurized modules, and primary truss structures such as deployable single fold beams, erectable beams and deployable double folds are given. Typical truss attachment devices and deployable backup procedures are also given.

  16. The Cambridge Structural Database.

    PubMed

    Groom, Colin R; Bruno, Ian J; Lightfoot, Matthew P; Ward, Suzanna C

    2016-04-01

    The Cambridge Structural Database (CSD) contains a complete record of all published organic and metal-organic small-molecule crystal structures. The database has been in operation for over 50 years and continues to be the primary means of sharing structural chemistry data and knowledge across disciplines. As well as structures that are made public to support scientific articles, it includes many structures published directly as CSD Communications. All structures are processed both computationally and by expert structural chemistry editors prior to entering the database. A key component of this processing is the reliable association of the chemical identity of the structure studied with the experimental data. This important step helps ensure that data is widely discoverable and readily reusable. Content is further enriched through selective inclusion of additional experimental data. Entries are available to anyone through free CSD community web services. Linking services developed and maintained by the CCDC, combined with the use of standard identifiers, facilitate discovery from other resources. Data can also be accessed through CCDC and third party software applications and through an application programming interface. PMID:27048719

  17. Trajectory structures and transport

    SciTech Connect

    Vlad, Madalina; Spineanu, Florin

    2004-11-01

    The special problem of transport in two-dimensional divergence-free stochastic velocity fields is studied by developing a statistical approach, the nested subensemble method. The nonlinear process of trapping determined by such fields generates trajectory structures whose statistical characteristics are determined. These structures strongly influence the transport.

  18. Structures in Space

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Astronaut Jerry L. Ross, anchored to the foot restraint on the Remote Manipulator System (RMS), approaches the tower-like Assembly Concept for Construction of Erectable Space Structures (ACCESS) device. The structure was just deployed by Ross and astronaut Sherwood Spring as the Atlantis flies over white clouds and blue ocean waters of the Atlantic.

  19. Folding Truss Structure

    NASA Technical Reports Server (NTRS)

    Warren, Aubrey D.

    1988-01-01

    Concept for foldable and deployable truss offers advantages of strength, rigidity, and mechanical simplicity. Structure consists of series of boxlike bays with 9-ft sides. Each box has panels on top and bottom and two sides. Two remaining sides open. Panels hinged at connecting edges. Adapted to terrestrial transportable structures, scaffolds, cranes, and rows of cubicles.

  20. Frontiers of Nuclear Structure

    SciTech Connect

    Nazarewicz, Witold

    1997-12-31

    Current developments in nuclear structure at the `limits` are discussed. The studies of nuclear behavior at extreme conditions provide us with invaluable information about the nature of the nuclear interaction and nucleonic correlations at various energy-distance scales. In this talk frontiers of nuclear structure are briefly reviewed from a theoretical perspective, mainly concentrating on medium-mass and heavy nuclei.

  1. Electron Structure of Francium

    NASA Astrophysics Data System (ADS)

    Koufos, Alexander

    2012-02-01

    This talk presents the first calculations of the electronic structure of francium for the bcc, fcc and hcp structures, using the Augmented Plane Wave (APW) method in its muffin-tin and linearized general potential forms. Both the Local Density Approximation (LDA) and Generalized Gradient Approximation (GGA), were used to calculate the electronic structure and total energy of francium (Fr). The GGA and LDA both found the total energy of the hcp structure slightly below that of the fcc and bcc structure, respectively. This is in agreement with similar results for the other alkali metals using the same methodology. The equilibrium lattice constant, bulk modulus and superconductivity parameters were calculated. We found that under pressures, in the range of 1-5 GPa, Fr could be a superconductor at a critical temperature of about 4K.

  2. Inflatable nested toroid structure

    NASA Technical Reports Server (NTRS)

    Johnson, Christopher J. (Inventor); Raboin, Jasen L. (Inventor); Spexarth, Gary R. (Inventor)

    2011-01-01

    An inflatable structure comprises at least two generally toroidal, inflatable modules. When in a deployed mode, the first, inner module has a major diameter less than that of a second, outer module and is positioned within the inner circumference of the outer module such that the first module is nested circumferentially alongside the second module. The inflatable structure, in a non-deployed, non-inflated mode, is of compact configuration and adapted to be transported to a site of deployment. When deployed, the inflatable structure is of substantially increased interior volume. In one embodiment, access between the interior of the first module and the second module is provided by at least one port or structural pass-through. In another embodiment, the inflatable structure includes at least one additional generally toroidal module external of and circumferentially surrounding the second module.

  3. Optoelectronic Mounting Structure

    DOEpatents

    Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R. F.; Bryan, Robert P.; Carson, Richard F.; Chu, Dahwey; Duckett, III, Edwin B.; McCormick, Frederick B.; Peterson, David W.; Peterson, Gary D.; Reber, Cathleen A.; Reysen, Bill H.

    2004-10-05

    An optoelectronic mounting structure is provided that may be used in conjunction with an optical transmitter, receiver or transceiver module. The mounting structure may be a flexible printed circuit board. Thermal vias or heat pipes in the head region may transmit heat from the mounting structure to the heat spreader. The heat spreader may provide mechanical rigidity or stiffness to the heat region. In another embodiment, an electrical contact and ground plane may pass along a surface of the head region so as to provide an electrical contact path to the optoelectronic devices and limit electromagnetic interference. In yet another embodiment, a window may be formed in the head region of the mounting structure so as to provide access to the heat spreader. Optoelectronic devices may be adapted to the heat spreader in such a manner that the devices are accessible through the window in the mounting structure.

  4. Iconicity as structure mapping

    PubMed Central

    Emmorey, Karen

    2014-01-01

    Linguistic and psycholinguistic evidence is presented to support the use of structure-mapping theory as a framework for understanding effects of iconicity on sign language grammar and processing. The existence of structured mappings between phonological form and semantic mental representations has been shown to explain the nature of metaphor and pronominal anaphora in sign languages. With respect to processing, it is argued that psycholinguistic effects of iconicity may only be observed when the task specifically taps into such structured mappings. In addition, language acquisition effects may only be observed when the relevant cognitive abilities are in place (e.g. the ability to make structural comparisons) and when the relevant conceptual knowledge has been acquired (i.e. information key to processing the iconic mapping). Finally, it is suggested that iconicity is better understood as a structured mapping between two mental representations than as a link between linguistic form and human experience. PMID:25092669

  5. Trends in aerospace structures

    NASA Technical Reports Server (NTRS)

    Card, M. F.

    1978-01-01

    Recent developments indicate that there may soon be a revolution in aerospace structures. Increases in allowable operational stress levels, utilization of high-strength, high-toughness materials, and new structural concepts will highlight this advancement. Improved titanium and aluminum alloys and high-modulus, high-strength advanced composites, with higher specific properties than aluminum and high-strength nickel alloys, are expected to be the principal materials. Significant advances in computer technology will cause major changes in the preliminary design cycle and permit solutions of otherwise too-complex interactive structural problems and thus the development of vehicles and components of higher performance. The energy crisis will have an impact on material costs and choices and will spur the development of more weight-efficient structures. There will also be significant spinoffs of aerospace structures technology, particularly in composites and design/analysis software.

  6. Spin structure functions

    SciTech Connect

    Jian-ping Chen, Alexandre Deur, Sebastian Kuhn, Zein-eddine Meziani

    2011-06-01

    Spin-dependent observables have been a powerful tool to probe the internal structure of the nucleon and to understand the dynamics of the strong interaction. Experiments involving spin degrees of freedom have often brought out surprises and puzzles. The so-called "spin crisis" in the 1980s revealed the limitation of naive quark-parton models and led to intensive worldwide efforts, both experimental and theoretical, to understand the nucleon spin structure. With high intensity and high polarization of both the electron beam and targets, Jefferson Lab has the world's highest polarized luminosity and the best figure-of-merit for precision spin structure measurements. It has made a strong impact in this subfield of research. This chapter will highlight Jefferson Lab's unique contributions in the measurements of valence quark spin distributions, in the moments of spin structure functions at low to intermediate Q2, and in the transverse spin structure.

  7. Iconicity as structure mapping.

    PubMed

    Emmorey, Karen

    2014-09-19

    Linguistic and psycholinguistic evidence is presented to support the use of structure-mapping theory as a framework for understanding effects of iconicity on sign language grammar and processing. The existence of structured mappings between phonological form and semantic mental representations has been shown to explain the nature of metaphor and pronominal anaphora in sign languages. With respect to processing, it is argued that psycholinguistic effects of iconicity may only be observed when the task specifically taps into such structured mappings. In addition, language acquisition effects may only be observed when the relevant cognitive abilities are in place (e.g. the ability to make structural comparisons) and when the relevant conceptual knowledge has been acquired (i.e. information key to processing the iconic mapping). Finally, it is suggested that iconicity is better understood as a structured mapping between two mental representations than as a link between linguistic form and human experience.

  8. Adaptive structures. [for space applications

    NASA Technical Reports Server (NTRS)

    Wada, B. K.; Fanson, J. L.; Crawley, E. F.

    1990-01-01

    Current research in the field of advanced adaptive structures for space applications is reviewed. A classification of adaptive structures is proposed whereby such structures are subdivided into adaptive, sensory, controlled, active, and intelligent structures. The definition and properties of each type of adaptive structures are presented, and methods of structure control are discussed.

  9. Solution Accounts for Structural Damping

    NASA Technical Reports Server (NTRS)

    Roussos, L. A.; Hyer, M. W.; Thornton, E. A.

    1982-01-01

    New analytical technique determines dynamic response of damped structures dominated by internal structural damping mechanisms. Though structural damping is often negligible compared with damping due to air friction and friction in joints, structural damping can be of major importance in structures having heavy damping treatments or in outer-space structures. Finite-element model includes nonlinear, nonviscous internal damping.

  10. Mobile marine operations structure

    SciTech Connect

    Bhalaik, A.; Braddick, P.W.; Brittin, D.S.; Johnson, G.L.

    1987-09-22

    This patent describes the process of installing a marine operations structure in a pre-determined sea floor location. The structure has a central core and a support base having at least two differently sloped ice wall surfaces for achieving fracturing of ice features, and having at least two series of circumferentially arranged ballast tanks. It consists of positioning the structure over a selected sea floor location by the use of at least three tug boats connected to the structure by tension cables arranged radially with respect to the structure; flooding a first series of lower ballast tanks in a sequential ballasting operation; flooding a second series of ballast tanks located at a higher elevation within the structure than the first series of ballast tanks; maintaining radial forces along the tension cables during the flooding steps; and after the structure has become founded on the bottom of the sea, pumping sea waver into fluid tanks some of which are located at an elevation above the water level.

  11. Photonic structures in biology.

    PubMed

    Vukusic, Pete; Sambles, J Roy

    2003-08-14

    Millions of years before we began to manipulate the flow of light using synthetic structures, biological systems were using nanometre-scale architectures to produce striking optical effects. An astonishing variety of natural photonic structures exists: a species of Brittlestar uses photonic elements composed of calcite to collect light, Morpho butterflies use multiple layers of cuticle and air to produce their striking blue colour and some insects use arrays of elements, known as nipple arrays, to reduce reflectivity in their compound eyes. Natural photonic structures are providing inspiration for technological applications.

  12. Tectonosphere: Structure and evolution

    NASA Astrophysics Data System (ADS)

    Belousov, V. V.

    This volume includes papers on the structure and evolution of the earth tectonosphere. Attention is given to the relationship between crust and upper mantle structures and plate tectonics, and the major patterns in the internal structure and the spatial distribution of Mediterranian folded regions. Other papers are on the formational types of ophiolite profiles and the interpretation of ophiolites as remnants of oceanic crust; the relationship between continental volcanism, xenoliths, and lithospheric platform tectonics; and the shallow-water facies of the world ocean. Particular consideration is given to the magnetic field of the oceans and the Vine-Matthews (1963) hypothesis.

  13. Progressive failure of structures

    NASA Technical Reports Server (NTRS)

    Khozeimeh, K.; Toridis, G. T. G.; Zanganeh, S. E.

    1978-01-01

    A procedure is presented for determining the nonlinear behavior of structures subjected to extreme loading and the possibility of development of potential for progressive failure. The methodology takes into account the effect of both material and geometric nonlinearities. At a given stage of analysis, the individual components of the structure are checked against predetermined failure criteria. Subsequently, the failing components are removed and the modified structure is analyzed for overall failure. Examples, obtained from a computer program based on the proposed procedure, showing the applicability of the method are presented.

  14. ACEE composite structures technology

    NASA Technical Reports Server (NTRS)

    Klotzsche, M. (Compiler)

    1984-01-01

    The NASA Aircraft Energy Efficiency (ACEE) Composite Primary Aircraft Structures Program has made significant progress in the development of technology for advanced composites in commercial aircraft. Commercial airframe manufacturers have demonstrated technology readiness and cost effectiveness of advanced composites for secondary and medium primary components and have initiated a concerted program to develop the data base required for efficient application to safety-of-flight wing and fuselage structures. Oral presentations were compiled into five papers. Topics addressed include: damage tolerance and failsafe testing of composite vertical stabilizer; optimization of composite multi-row bolted joints; large wing joint demonstation components; and joints and cutouts in fuselage structure.

  15. Deployable geodesic truss structure

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin M., Jr. (Inventor); Rhodes, Marvin D. (Inventor); Simonton, J. Wayne (Inventor)

    1987-01-01

    A deployable geodesic truss structure which can be deployed from a stowed state to an erected state is described. The truss structure includes a series of bays, each bay having sets of battens connected by longitudinal cross members which give the bay its axial and torsional stiffness. The cross members are hinged at their mid point by a joint so that the cross members are foldable for deployment or collapsing. The bays are deployed and stabilized by actuator means connected between the mid point joints of the cross members. Hinged longerons may be provided to also connect the sets of battens and to collapse for stowing with the rest of the truss structure.

  16. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Loewy, R.; Wiberley, S. E.

    1986-01-01

    Overall emphasis is on basic long-term research in the following categories: constituent materials, composite materials, generic structural elements, processing science technology; and maintaining long-term structural integrity. Research in basic composition, characteristics, and processing science of composite materials and their constituents is balanced against the mechanics, conceptual design, fabrication, and testing of generic structural elements typical of aerospace vehicles so as to encourage the discovery of unusual solutions to present and future problems. Detailed descriptions of the progress achieved in the various component parts of this comprehensive program are presented.

  17. Australia's Political Structure.

    ERIC Educational Resources Information Center

    Sawer, Geoffrey

    1984-01-01

    Australia is an independent nation-state, federally constituted under a democratic parliamentary system. Being part of the Commonwealth of Nations, with feelings of loyalty to the Crown, Australia is also a democratic monarchy. Its political structure is discussed. (RM)

  18. Corotating shock structures

    NASA Technical Reports Server (NTRS)

    Ogilvie, K. W.

    1972-01-01

    Consideration of observed interplanetary shocks leads to the conclusion that a corotating forward shock has not been unambiguously identified at 1 AU. A reverse shock identified in September 1967 is a likely candidate for a corotating structure.

  19. Nonlinear damping in structures

    NASA Technical Reports Server (NTRS)

    Chang, C. S.

    1970-01-01

    Experimental results prove the feasibility of substructure testing to measure local damping properties directly. Dynamic responses of a structure can be predicted quantitatively, and specimens are less costly and more easily tested with better controlled tests and environments.

  20. Structure of the Heart

    MedlinePlus

    ... Central Nervous System Peripheral Nervous System Review Quiz Endocrine System Characteristics of Hormones Endocrine Glands & Their Hormones Pituitary & ... Thyroid & Parathyroid Glands Adrenal Gland Pancreas Gonads Other Endocrine Glands ... Cardiovascular System Heart Structure of the Heart Physiology of the ...

  1. Structural Organization of DNA.

    ERIC Educational Resources Information Center

    Banfalvi, Gaspar

    1986-01-01

    Explains the structural organization of DNA by providing information on the primary, secondary, tertiary, and higher organization levels of the molecule. Also includes illustrations and descriptions of sign-inversion and rotating models for supercoiling of DNA. (ML)

  2. Grounding of space structures

    NASA Technical Reports Server (NTRS)

    Bosela, P. A.; Fertis, D. G.; Shaker, F. J.

    1992-01-01

    Space structures, such as the Space Station solar arrays, must be extremely light-weight, flexible structures. Accurate prediction of the natural frequencies and mode shapes is essential for determining the structural adequacy of components, and designing a controls system. The tension pre-load in the 'blanket' of photovoltaic solar collectors, and the free/free boundary conditions of a structure in space, causes serious reservations on the use of standard finite element techniques of solution. In particular, a phenomenon known as 'grounding', or false stiffening, of the stiffness matrix occurs during rigid body rotation. This paper examines the grounding phenomenon in detail. Numerous stiffness matrices developed by others are examined for rigid body rotation capability, and found lacking. A force imbalance inherent in the formulations examined is the likely cause of the grounding problem, suggesting the need for a directed force formulation.

  3. Bioinspired structured surfaces.

    PubMed

    Bhushan, Bharat

    2012-01-24

    Nature has evolved objects with desired functionality using commonly found materials. Nature capitalizes on hierarchical structures to achieve functionality. The understanding of the functions provided by objects and processes found in nature can guide us to produce nanomaterials, nanodevices, and processes with desirable functionality. Various natural objects which provide functionality of commercial interest have been characterized to understand how a natural object provides functionality. We have modeled and fabricated structures in the lab using nature's route and developed optimum structures. Once it is understood how nature does it, optimum structures have been fabricated using smart materials and fabrication techniques. This feature article provides an overview of four topics: Lotus effect, rose petal effect, gecko feet, and shark skin.

  4. ACEE composite structures technology

    NASA Technical Reports Server (NTRS)

    James, A. M.

    1984-01-01

    Topics addressed include: strength and hygrothermal response of L-1011 fin components; wing fuel containment and damage tolerance development; impact dynamics; acoustic transmission; fuselage structure; composite transport wing technology development; spar/assembly concepts.

  5. Other Fabric Structures

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Architects, engineers and building owners are turning increasingly to fabric structures because of their aesthetic appeal, relatively low initial cost, low maintenance outlays, energy efficiency and good space utilization. Several examples are shown.

  6. Dielectric assist accelerating structure

    NASA Astrophysics Data System (ADS)

    Satoh, D.; Yoshida, M.; Hayashizaki, N.

    2016-01-01

    A higher-order TM02 n mode accelerating structure is proposed based on a novel concept of dielectric loaded rf cavities. This accelerating structure consists of ultralow-loss dielectric cylinders and disks with irises which are periodically arranged in a metallic enclosure. Unlike conventional dielectric loaded accelerating structures, most of the rf power is stored in the vacuum space near the beam axis, leading to a significant reduction of the wall loss, much lower than that of conventional normal-conducting linac structures. This allows us to realize an extremely high quality factor and a very high shunt impedance at room temperature. A simulation of a 5 cell prototype design with an existing alumina ceramic indicates an unloaded quality factor of the accelerating mode over 120 000 and a shunt impedance exceeding 650 M Ω /m at room temperature.

  7. NASA Now: Inflatable Structures

    NASA Video Gallery

    NASA senior research engineer Judith Watson is one of a team of engineers at NASA’s Langley Research Center who are studying inflatable structures that might one day be used to establish an outpo...

  8. Stellar atmospheric structural patterns

    NASA Technical Reports Server (NTRS)

    Thomas, R. N.

    1983-01-01

    The thermodynamics of stellar atmospheres is discussed. Particular attention is given to the relation between theoretical modeling and empirical evidence. The characteristics of distinctive atmospheric regions and their radical structures are discussed.

  9. Encapsulation with structured triglycerides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lipids provide excellent materials to encapsulate bioactive compounds for food and pharmaceutical applications. Lipids are renewable, biodegradable, and easily modified to provide additional chemical functionality. The use of structured lipids that have been modified with photoactive properties are ...

  10. Determining structural performance

    NASA Technical Reports Server (NTRS)

    Ernst, Michael A.; Kiraly, Louis J.

    1987-01-01

    An overview is given of the methods and concepts developed to enhance and predict structural dynamic characteristics of advanced aeropropulsion systems. Aeroelasticity, Vibration Control, Dynamic Systems, and Computational Structural Methods are four disciplines that make up the research program at NASA/Lewis Research Center. The Aeroelasticity program develops analytical and experimental methods to minimize flutter and forced vibration of aerospace propulsion systems. Both frequency domain and time domain methods have been developed for applications on the turbofan, turbopump, and advanced turboprop. To improve life and performance, the Vibration Control program conceives, analyzes, develops, and demonstrates new methods to control vibrations in aerospace systems. Active and passive vibration control is accomplished with electromagnetic dampers, magnetic bearings, and piezoelectric crystals to control rotor vibrations. The Dynamic Systems program analyzes and verifies the dynamics of interacting systems, as well as develops concepts and methods for high-temperature dynamic seals. The Computational Structural Methods program uses computer science to improve solutions of structural problems.

  11. Structural Determination of Circulation.

    ERIC Educational Resources Information Center

    Blankenburg, William B.

    1981-01-01

    Analyzes the effects of both structural factors (demographics, economic conditions, and competition) and discretionary factors (content, design, and marketing techniques) and concludes that it is the former that determine a newspaper's circulation. (FL)

  12. Solar animal structure

    SciTech Connect

    Kim, H.K.

    1984-07-31

    The present invention entails an animal housing structure equipped with a solar heating system for heating the structure. Solar energy is collected by a roof-attic solar collector arrangement and the collected solar energy in the form of heat is transferred to passing air. The heated passing air is selectively directed to the ground underlying the structure and is channeled generally horizontally through the underlying ground at a selected depth below ground level. Heat from the air is transferred to the earth below ground level and this heat is then slowly transferred upwardly through the ground towards ground level where it is ultimately emitted from the earth and acts to heat the interior of the structure and provide warmth for the animals.

  13. School Administrator Grapevine Structure.

    ERIC Educational Resources Information Center

    Licata, Joseph W.; Hack, Walter G.

    1980-01-01

    A study reveals that principals' grapevine structure shows both "guild-like" and "clan-like" grouping and reflects the patterns of occupational socialization of school principals and informal boundary spanning processes. (Author/JM)

  14. Vascular structures in dermoscopy*

    PubMed Central

    Ayhan, Erhan; Ucmak, Derya; Akkurt, ZeynepMeltem

    2015-01-01

    Dermoscopy is an aiding method in the visualization of the epidermis and dermis. It is usually used to diagnose melanocytic lesions. In recent years, dermoscopy has increasingly been used to diagnose non-melanocytic lesions. Certain vascular structures, their patterns of arrangement and additional criteria may demonstrate lesion-specific characteristics. In this review, vascular structures and their arrangements are discussed separately in the light of conflicting views and an overview of recent literature. PMID:26375224

  15. Structural traps 5

    SciTech Connect

    Foster, N.H.; Beaumont, E.A.

    1991-01-01

    This book contains studies of oil and gas fields that are mainly structural in nature. Stratigraphy controls the extend of the reservoir in the traps of several fields, but overall, the main trapping features within the group of fields in this volume are structural. Fields covered in this volume include: Endicott Field, Point Arguello Field, West Puerto Chiquito Field, Dukhan Field, Sendji Field, Ruston Field, Raudhatain Field, Hassi Messaoud Field, Snapper Field, Tirrawarra Field, and Sacha Field.

  16. REACTOR MODERATOR STRUCTURE

    DOEpatents

    Greenstreet, B.L.

    1963-12-31

    A system for maintaining the alignment of moderator block structures in reactors is presented. Integral restraining grids are placed between each layer of blocks in the moderator structure, at the top of the uppermost layer, and at the bottom of the lowermost layer. Slots are provided in the top and bottom surfaces of the moderator blocks so as to provide a keying action with the grids. The grids are maintained in alignment by vertical guiding members disposed about their peripheries. (AEC)

  17. Integrated support structure

    NASA Technical Reports Server (NTRS)

    Bruneau, Stephen D.; Campbell, John T.; Struven, Christopher A.

    1990-01-01

    This Major Qualifying Project is part of the Advanced Space Design Program at WPI. The goal is to design a support structure for a NASA GetAway Special experimental canister. The payload integration, weight, volume, and structural integrity of the canister as specified by NASA guidelines were studied. The end result is a complete set of design drawings with interface drawings and data to specify the design and leave a base on which the next group can concentrate.

  18. Structured luminescence conversion layer

    DOEpatents

    Berben, Dirk; Antoniadis, Homer; Jermann, Frank; Krummacher, Benjamin Claus; Von Malm, Norwin; Zachau, Martin

    2012-12-11

    An apparatus device such as a light source is disclosed which has an OLED device and a structured luminescence conversion layer deposited on the substrate or transparent electrode of said OLED device and on the exterior of said OLED device. The structured luminescence conversion layer contains regions such as color-changing and non-color-changing regions with particular shapes arranged in a particular pattern.

  19. Meteorite Seymchan structure

    NASA Astrophysics Data System (ADS)

    Hontsova, S. S.; Petrova, E. V.; Muftahetdinova, R. F.; Chulanova, V. N.; Grokhovsky, V. I.

    2016-09-01

    The meteorite Seymchan specimen was studied using optical microscopy and scanning electron microscopy. Olivine grains have roundish shapes, which was formed during matter cooling. Different features of the metal structure such as plessite structure and Neimann bands were observed. The oxide edges were observed in the boundaries between phases. The oxides were formed in the terrestrial conditions. The boundary regions between metal and olivine in the meteorite contain grains of troilite, schreibersite, and chromite.

  20. Structure function monitor

    DOEpatents

    McGraw, John T.; Zimmer, Peter C.; Ackermann, Mark R.

    2012-01-24

    Methods and apparatus for a structure function monitor provide for generation of parameters characterizing a refractive medium. In an embodiment, a structure function monitor acquires images of a pupil plane and an image plane and, from these images, retrieves the phase over an aperture, unwraps the retrieved phase, and analyzes the unwrapped retrieved phase. In an embodiment, analysis yields atmospheric parameters measured at spatial scales from zero to the diameter of a telescope used to collect light from a source.

  1. Structural analysis of glucans

    PubMed Central

    Novak, Miroslav

    2014-01-01

    Glucans are most widespread polysaccharides in the nature. There is a large diversity in their molecular weight and configuration depending on the original source. According to the anomeric structure of glucose units it is possible to distinguish linear and branched α-, β- as well as mixed α,β-glucans with various glycoside bond positions and molecular masses. Isolation of glucans from raw sources needs removal of ballast compounds including proteins, lipids, polyphenols and other polysaccharides. Purity control of glucan fractions is necessary to evaluate the isolation and purification steps; more rigorous structural analyses of purified polysaccharides are required to clarify their structure. A set of spectroscopic, chemical and separation methods are used for this purpose. Among them, NMR spectroscopy is known as a powerful tool in structural analysis of glucans both in solution and in solid state. Along with chemolytic methods [methylation analysis (MA), periodate oxidation, partial chemical or enzymatic hydrolysis, etc.], correlation NMR experiments are able to determine the exact structure of tested polysaccharides. Vibration spectroscopic methods (FTIR, Raman) are sensitive to anomeric structure of glucans and can be used for purity control as well. Molecular weight distribution, homogeneity and branching of glucans can be estimated by size-exclusion chromatography (SEC), laser light scattering (LLS) and viscometry. PMID:25332993

  2. Integral Textile Ceramic Structures

    NASA Astrophysics Data System (ADS)

    Marshall, David B.; Cox, Brian N.

    2008-08-01

    A new paradigm for ceramic composite structural components enables functionality in heat exchange, transpiration, detailed shape, and thermal strain management that significantly exceeds the prior art. The paradigm is based on the use of three-dimensional fiber reinforcement that is tailored to the specific shape, stress, and thermal requirements of a structural application and therefore generally requires innovative textile methods for each realization. Key features include the attainment of thin skins (less than 1 mm) that are nevertheless structurally robust, transpiration holes formed without cutting fibers, double curvature, compliant integral attachment to other structures that avoids thermal stress buildup, and microcomposite ceramic matrices that minimize spalling and allow the formation of smooth surfaces. All these features can be combined into structures of very varied gross shape and function, using a wide range of materials such as all-oxide systems and SiC and carbon fibers in SiC matrices. Illustrations are drawn from rocket nozzles, thermal protection systems, and gas turbine engines. The new design challenges that arise for such material/structure systems are being met by specialized computational modeling that departs significantly in the representation of materials behavior from that used in conventional finite element methods.

  3. Pleated and Creased Structures

    NASA Astrophysics Data System (ADS)

    Dudte, Levi; Wei, Zhiyan; Mahadevan, L.

    2012-02-01

    The strategic placement of curved folds on a paper annulus produces saddle-shaped origami. These exotic geometries resulting from simple design processes motivate our development of a computational tool to simulate the stretching, bending and folding of thin sheets of material. We seek to understand the shape of the curved origami figure by applying the computational tool to simulate a thin annulus with single or multiple folds. We aim to quantify the static geometry of this simplified model in order to delineate methods for actuation and control of similar developable structures with curved folds. Miura-ori pattern is a periodic pleated structure defined in terms of 2 angles and 2 lengths. The unit cell embodies the basic element in all non-trivial pleated structures - the mountain or valley folds, wherein four folds come together at a single vertex. The ability of this structure to pack and unpack with a few degrees of freedom leads to their use in deployable structures such as solar sails and maps, just as this feature is useful in insect wings, plant leaves and flowers. We probe the qualitative and quantitative aspects of the mechanical behavior of these structures with a view to optimizing material performance.

  4. Structural disorder in eukaryotes.

    PubMed

    Pancsa, Rita; Tompa, Peter

    2012-01-01

    Based on early bioinformatic studies on a handful of species, the frequency of structural disorder of proteins is generally thought to be much higher in eukaryotes than in prokaryotes. To refine this view, we present here a comparative prediction study and analysis of 194 fully described eukaryotic proteomes and 87 reference prokaryotes for structural disorder. We found that structural disorder does distinguish eukaryotes from prokaryotes, but its frequency spans a very wide range in the two superkingdoms that largely overlap. The number of disordered binding regions and different Pfam domain types also contribute to distinguish eukaryotes from prokaryotes. Unexpectedly, the highest levels--and highest variability--of predicted disorder is found in protists, i.e. single-celled eukaryotes, often surpassing more complex eukaryote organisms, plants and animals. This trend contrasts with that of the number of domain types, which increases rather monotonously toward more complex organisms. The level of structural disorder appears to be strongly correlated with lifestyle, because some obligate intracellular parasites and endosymbionts have the lowest levels, whereas host-changing parasites have the highest level of predicted disorder. We conclude that protists have been the evolutionary hot-bed of experimentation with structural disorder, in a period when structural disorder was actively invented and the major functional classes of disordered proteins established.

  5. RNA Thermodynamic Structural Entropy

    PubMed Central

    Garcia-Martin, Juan Antonio; Clote, Peter

    2015-01-01

    Conformational entropy for atomic-level, three dimensional biomolecules is known experimentally to play an important role in protein-ligand discrimination, yet reliable computation of entropy remains a difficult problem. Here we describe the first two accurate and efficient algorithms to compute the conformational entropy for RNA secondary structures, with respect to the Turner energy model, where free energy parameters are determined from UV absorption experiments. An algorithm to compute the derivational entropy for RNA secondary structures had previously been introduced, using stochastic context free grammars (SCFGs). However, the numerical value of derivational entropy depends heavily on the chosen context free grammar and on the training set used to estimate rule probabilities. Using data from the Rfam database, we determine that both of our thermodynamic methods, which agree in numerical value, are substantially faster than the SCFG method. Thermodynamic structural entropy is much smaller than derivational entropy, and the correlation between length-normalized thermodynamic entropy and derivational entropy is moderately weak to poor. In applications, we plot the structural entropy as a function of temperature for known thermoswitches, such as the repression of heat shock gene expression (ROSE) element, we determine that the correlation between hammerhead ribozyme cleavage activity and total free energy is improved by including an additional free energy term arising from conformational entropy, and we plot the structural entropy of windows of the HIV-1 genome. Our software RNAentropy can compute structural entropy for any user-specified temperature, and supports both the Turner’99 and Turner’04 energy parameters. It follows that RNAentropy is state-of-the-art software to compute RNA secondary structure conformational entropy. Source code is available at https://github.com/clotelab/RNAentropy/; a full web server is available at http

  6. RNA Thermodynamic Structural Entropy.

    PubMed

    Garcia-Martin, Juan Antonio; Clote, Peter

    2015-01-01

    Conformational entropy for atomic-level, three dimensional biomolecules is known experimentally to play an important role in protein-ligand discrimination, yet reliable computation of entropy remains a difficult problem. Here we describe the first two accurate and efficient algorithms to compute the conformational entropy for RNA secondary structures, with respect to the Turner energy model, where free energy parameters are determined from UV absorption experiments. An algorithm to compute the derivational entropy for RNA secondary structures had previously been introduced, using stochastic context free grammars (SCFGs). However, the numerical value of derivational entropy depends heavily on the chosen context free grammar and on the training set used to estimate rule probabilities. Using data from the Rfam database, we determine that both of our thermodynamic methods, which agree in numerical value, are substantially faster than the SCFG method. Thermodynamic structural entropy is much smaller than derivational entropy, and the correlation between length-normalized thermodynamic entropy and derivational entropy is moderately weak to poor. In applications, we plot the structural entropy as a function of temperature for known thermoswitches, such as the repression of heat shock gene expression (ROSE) element, we determine that the correlation between hammerhead ribozyme cleavage activity and total free energy is improved by including an additional free energy term arising from conformational entropy, and we plot the structural entropy of windows of the HIV-1 genome. Our software RNAentropy can compute structural entropy for any user-specified temperature, and supports both the Turner'99 and Turner'04 energy parameters. It follows that RNAentropy is state-of-the-art software to compute RNA secondary structure conformational entropy. Source code is available at https://github.com/clotelab/RNAentropy/; a full web server is available at http

  7. The Quality and Validation of Structures from Structural Genomics

    PubMed Central

    Domagalski, Marcin J.; Zheng, Heping; Zimmerman, Matthew D.; Dauter, Zbigniew; Wlodawer, Alexander; Minor, Wladek

    2014-01-01

    Quality control of three-dimensional structures of macromolecules is a critical step to ensure the integrity of structural biology data, especially those produced by structural genomics centers. Whereas the Protein Data Bank (PDB) has proven to be a remarkable success overall, the inconsistent quality of structures reveals a lack of universal standards for structure/deposit validation. Here, we review the state-of-the-art methods used in macromolecular structure validation, focusing on validation of structures determined by X-ray crystallography. We describe some general protocols used in the rebuilding and re-refinement of problematic structural models. We also briefly discuss some frontier areas of structure validation, including refinement of protein–ligand complexes, automation of structure redetermination, and the use of NMR structures and computational models to solve X-ray crystal structures by molecular replacement. PMID:24203341

  8. GENERAL VIEW OF DEHYDRATER (STRUCTURE 12), SHED (STRUCTURE 18), FRUIT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF DEHYDRATER (STRUCTURE 12), SHED (STRUCTURE 18), FRUIT TRAY STORAGE ROOM (STRUCTURE 11), WITH FRUIT DRYING AREA AND TRAM TRACKS IN FOREGROUND, FROM NORTHWEST - Stevens Ranch Complex, State Route 101, Coyote, Santa Clara County, CA

  9. Controls for space structures

    NASA Technical Reports Server (NTRS)

    Balas, Mark

    1991-01-01

    Assembly and operation of large space structures (LSS) in orbit will require robot-assisted docking and berthing of partially-assembled structures. These operations require new solutions to the problems of controls. This is true because of large transient and persistent disturbances, controller-structure interaction with unmodeled modes, poorly known structure parameters, slow actuator/sensor dynamical behavior, and excitation of nonlinear structure vibrations during control and assembly. For on-orbit assembly, controllers must start with finite element models of LSS and adapt on line to the best operating points, without compromising stability. This is not easy to do, since there are often unmodeled dynamic interactions between the controller and the structure. The indirect adaptive controllers are based on parameter estimation. Due to the large number of modes in LSS, this approach leads to very high-order control schemes with consequent poor stability and performance. In contrast, direct model reference adaptive controllers operate to force the LSS to track the desirable behavior of a chosen model. These schemes produce simple control algorithms which are easy to implement on line. One problem with their use for LSS has been that the model must be the same dimension as the LSS - i.e., quite large. A control theory based on the command generator tracker (CGT) ideas of Sobel, Mabins, Kaufman and Wen, Balas to obtain very low-order models based on adaptive algorithms was developed. Closed-loop stability for both finite element models and distributed parameter models of LSS was proved. In addition, successful numerical simulations on several LSS databases were obtained. An adaptive controller based on our theory was also implemented on a flexible robotic manipulator at Martin Marietta Astronautics. Computation schemes for controller-structure interaction with unmodeled modes, the residual mode filters or RMF, were developed. The RMF theory was modified to compensate

  10. Expert Cold Structure Development

    NASA Astrophysics Data System (ADS)

    Atkins, T.; Demuysere, P.

    2011-05-01

    The EXPERT Program is funded by ESA. The objective of the EXPERT mission is to perform a sub-orbital flight during which measurements of critical aero- thermodynamic phenomena will be obtained by using state-of-the-art instrumentation. As part of the EXPERT Flight Segment, the responsibility of the Cold Structure Development Design, Manufacturing and Validation was committed to the Belgian industrial team SONACA/SABCA. The EXPERT Cold Structure includes the Launcher Adapter, the Bottom Panel, the Upper Panel, two Cross Panels and the Parachute Bay. An additional Launcher Adapter was manufactured for the separation tests. The selected assembly definition and manufacturing technologies ( machined parts and sandwich panels) were dictated classically by the mass and stiffness, but also by the CoG location and the sensitive separation interface. Used as support for the various on-board equipment, the Cold Structure is fixed to but thermally uncoupled from the PM 1000 thermal shield. It is protect on its bottom panel by a thermal blanket. As it is a protoflight, analysis was the main tool for the verification. Low level stiffness and modal analysis tests have also been performed on the Cold Structure equipped with its ballast. It allowed to complete its qualification and to prepare SONACA/SABCA support for the system dynamic tests foreseen in 2011. The structure was finally coated with a thermal control black painting and delivered on time to Thales Alenia Space-Italy end of March 201.

  11. Solar efficient structure

    SciTech Connect

    Arenas, F.B.

    1985-02-12

    A solar efficient structure is disclosed which comprises a central chase positioned vertically within the structure and connected in fluid communication with a duct network positioned in thermal contact with the ground and with the attic of the structure. A fan is provided for circulating air through a perforated attic duct, through the various rooms of the structure, and through the duct network and the chase. In one embodiment, the fan is reversible so as to circulate the air in one direction, or in the other direction. When operating in the heating mode, the ground acts as a heat source to heat the air circulating through the duct network. Conversely, when operating in the cooling mode, the ground acts as a heat sink to cool the airflow circulating therethrough. A dehumidifier, and a heating or cooling means is provided for assisting in the conditioning of the circulating airflow. In one embodiment, the heating means comprises a greenhouse room which permits ultraviolet radiation to enter and heat the air contained therein, and a damper means for controlling the flow rate of the air circulating through the greenhouse room. The structure is fully insulated and includes a vent skin positioned about the exterior walls and the roof thereof. A method is disclosed for insulating the roof line with loose insulation.

  12. Structural graphitic carbon foams

    SciTech Connect

    Kearns, K.M.; Anderson, H.J.

    1998-12-31

    Graphitic carbon foams are a unique material form with very high structural and thermal properties at a light weight. A process has been developed to produce microcellular, open-celled graphitic foams. The process includes heating a mesophase pitch preform above the pitch melting temperature in a pressurized reactor. At the appropriate time, the pressure is released, the gas nucleates bubbles, and these bubbles grow forming the pitch into the foam structure. The resultant foamed pitch is then stabilized in an oxygen environment. At this point a rigid structure exists with some mechanical integrity. The foam is then carbonized to 800 C followed by a graphitization to 2700 C. The shear action from the growing bubbles aligns the graphitic planes along the foam struts to provide the ideal structure for good mechanical properties. Some of these properties have been characterized for some of the foam materials. It is known that variations of the blowing temperature, blowing pressure and saturation time result in foams of variously sized with mostly open pores; however, the mechanism of bubble nucleation is not known. Therefore foams were blown with various gases to begin to determine the nucleation method. These gases are comprised of a variety of molecular weights as well as a range of various solubility levels. By examining the resultant structures of the foam, differences were noted to develop an explanation of the foaming mechanism.

  13. PRSEUS Structural Concept Development

    NASA Technical Reports Server (NTRS)

    Velicki, Alex; Jegley, Dawn

    2014-01-01

    A lighter, more robust airframe is one of the key technological advancements necessary for the successful launch of any large next-generation transport aircraft. Such a premise dictates that considerable improvements beyond current state-of-the-art aluminum structures is needed, and that improvements of this magnitude will require an extensive use of composite materials that are not only lightweight, but also economical to produce. To address this challenge, researchers at NASA and The Boeing Company are developing a novel structural concept called the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) under the Environmentally Responsible Aviation (ERA) Project. It is an integrally stiffened panel concept that is stitched together and designed to maintain residual load-carrying capabilities under a variety of damage scenarios. In addition to improved structural performance, an important facet of this unique arrangement of stitched carbon fibers is its innovative manufacturing method that has the potential to lower fabrication costs by eliminating fasteners and autoclave cures. The rationale and development status for this new approach forms the basis of the work described in this paper. The test specimens described herein were fabricated, or are currently being fabricated, by The Boeing Company, while the structural analyses and testing tasks are being performed by NASA and Boeing personnel.

  14. Determining structural performance

    NASA Technical Reports Server (NTRS)

    Ernst, Michael A. (Editor); Brown, Gerald; Dirusso, Eliseo; Fleming, David; Janetzke, David; Kascak, Albert; Kaza, Krishna; Kielb, Robert; Kiraly, Louis J.; Lawrence, Charles

    1990-01-01

    An overview of the methods and concepts developed to enhance and predict structural dynamic characteristics of advanced aeropropulsion systems is presented. Aeroelasticity, vibration control, dynamic systems, and computational structural methods are four disciplines that make up the structural dynamic effort at LeRC. The aeroelasticity program develops analytical and experimental methods for minimizing flutter and forced vibration of aerospace propulsion systems. Both frequency domain and time domain methods were developed for applications on the turbofan, turbopump, and advanced turboprop. In order to improve life and performance, the vibration control program conceives, analyzes, develops, and demonstrates new methods for controlling vibrations in aerospace systems. Active and passive vibration control is accomplished with electromagnetic dampers, magnetic bearings, and piezoelectric crystals to control rotor vibrations. The dynamic systems program analyzes and verifies the dynamics of interacting systems, as well as develops concepts and methods for high-temperature dynamic seals. Work in this field involves the analysis and parametric identification of large, nonlinear, damped, stochastic systems. The computational structural methods program exploits modern computer science as an aid to the solutions of structural problems.

  15. Designing plasmonic structures

    NASA Astrophysics Data System (ADS)

    Flammer, P. David

    This thesis describes methods and results used in the design of various photonic structures. The emphasis of this thesis is in the theoretical and computational methods employed in the design. Many structures were fabricated and experimentally characterized confirming simulation results. Theoretically, surface plasmons (SPs) or more generally the study of light near micro- or nano-fabricated metallic surfaces, play a major role in all structures in this thesis. An effective work-flow in designing "plasmonic" structures is detailed. Various applications are then discussed: (1) Enhanced transmission through subwavelength apertures in metal films; (2) long range SP hybrid waveguides for use in the area of micro-electronics; (3) circular micro-polarizers, which also filter for a specific color band, combined with linear polarizers for full stokes polarization imaging; and (4) using plasmonic couplers to increase efficiency of metal-insulator-metal (MIM) tunnel junction detectors for use in the low THz. General conclusions about the efficacy of plasmonic structures, or the lack thereof, in these applications are discussed.

  16. Carbon Structure Hazard Control

    NASA Technical Reports Server (NTRS)

    Yoder, Tommy; Greene, Ben; Porter, Alan

    2015-01-01

    Carbon composite structures are widely used in virtually all advanced technology industries for a multitude of applications. The high strength-to-weight ratio and resistance to aggressive service environments make them highly desirable. Automotive, aerospace, and petroleum industries extensively use, and will continue to use, this enabling technology. As a result of this broad range of use, field and test personnel are increasingly exposed to hazards associated with these structures. No single published document exists to address the hazards and make recommendations for the hazard controls required for the different exposure possibilities from damaged structures including airborne fibers, fly, and dust. The potential for personnel exposure varies depending on the application or manipulation of the structure. The effect of exposure to carbon hazards is not limited to personnel, protection of electronics and mechanical equipment must be considered as well. The various exposure opportunities defined in this document include pre-manufacturing fly and dust, the cured structure, manufacturing/machining, post-event cleanup, and post-event test and/or evaluation. Hazard control is defined as it is applicable or applied for the specific exposure opportunity. The carbon exposure hazard includes fly, dust, fiber (cured/uncured), and matrix vapor/thermal decomposition products. By using the recommendations in this document, a high level of confidence can be assured for the protection of personnel and equipment.

  17. Structural power flow measurement

    SciTech Connect

    Falter, K.J.; Keltie, R.F.

    1988-12-01

    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  18. The Structure Lacuna

    PubMed Central

    Boeyens, Jan C.A.; Levendis, Demetrius C.

    2012-01-01

    Molecular symmetry is intimately connected with the classical concept of three-dimensional molecular structure. In a non-classical theory of wave-like interaction in four-dimensional space-time, both of these concepts and traditional quantum mechanics lose their operational meaning, unless suitably modified. A required reformulation should emphasize the importance of four-dimensional effects like spin and the symmetry effects of space-time curvature that could lead to a fundamentally different understanding of molecular symmetry and structure in terms of elementary number theory. Isolated single molecules have no characteristic shape and macro-biomolecules only develop robust three-dimensional structure in hydrophobic response to aqueous cellular media. PMID:22942753

  19. Superalloy Lattice Block Structures

    NASA Technical Reports Server (NTRS)

    Nathal, M. V.; Whittenberger, J. D.; Hebsur, M. G.; Kantzos, P. T.; Krause, D. L.

    2004-01-01

    Initial investigations of investment cast superalloy lattice block suggest that this technology will yield a low cost approach to utilize the high temperature strength and environmental resistance of superalloys in lightweight, damage tolerant structural configurations. Work to date has demonstrated that relatively large superalloy lattice block panels can be successfully investment cast from both IN-718 and Mar-M247. These castings exhibited mechanical properties consistent with the strength of the same superalloys measured from more conventional castings. The lattice block structure also accommodates significant deformation without failure, and is defect tolerant in fatigue. The potential of lattice block structures opens new opportunities for the use of superalloys in future generations of aircraft applications that demand strength and environmental resistance at elevated temperatures along with low weight.

  20. Structural Acoustics and Vibrations

    NASA Astrophysics Data System (ADS)

    Chaigne, Antoine

    This structural chapter is devoted to vibrations of structures and to their coupling with the acoustic field. Depending on the context, the radiated sound can be judged as desirable, as is mostly the case for musical instruments, or undesirable, like noise generated by machinery. In architectural acoustics, one main goal is to limit the transmission of sound through walls. In the automobile industry, the engineers have to control the noise generated inside and outside the passenger compartment. This can be achieved by means of passive or active damping. In general, there is a strong need for quieter products and better sound quality generated by the structures in our daily environment.

  1. Gene structure and expression

    SciTech Connect

    Hawkins, J. )

    1990-01-01

    This book describes the structure of genes in molecular terms and summarizes present knowledge about how their activity is regulated. It covers a range of topics, including a review of the structure and replication of DNA, transcription and translation, prokaryotic and eukaryotic gene organization and expression, retroviruses and oncogenes. The book also includes a chapter on the methodology of DNA manipulation including sections on site-directed mutagenesis, the polymerase chain reaction, reporter genes and restriction fragment length polymorphisms. The hemoglobin gene system and the genetics of the proteins of the immune system are presented in the latter half of the book to show the structure and expression of the most well-studied systems in higher eukaryotes. The final chapter reviews the differences between prokaryotic and the eukaryotic genomes.

  2. Computational engine structural analysis

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Johns, R. H.

    1986-01-01

    A significant research activity at the NASA Lewis Research Center is the computational simulation of complex multidisciplinary engine structural problems. This simulation is performed using computational engine structural analysis (CESA) which consists of integrated multidisciplinary computer codes in conjunction with computer post-processing for problem-specific application. A variety of the computational simulations of specific cases are described in some detail in this paper. These case studies include: (1) aeroelastic behavior of bladed rotors, (2) high velocity impact of fan blades, (3) blade-loss transient response, (4) rotor/stator/squeeze-film/bearing interaction, (5) blade-fragment/rotor-burst containment, and (6) structural behavior of advanced swept turboprops. These representative case studies are selected to demonstrate the breath of the problems analyzed and the role of the computer including post-processing and graphical display of voluminous output data.

  3. Rethinking cell structure.

    PubMed Central

    Penman, S

    1995-01-01

    Cell structure, emerging from behind the veil of conventional electron microscopy, appears far more complex than formerly realized. The standard plastic-embedded, ultrathin section can image only what is on the section surface and masks the elaborate networks of the cytoplasm and nucleus. Embedment-free electron microscopy gives clear, high-contrast micrographs of cell structure when combined with removal of obscuring material such as soluble proteins. The resinless ultrathin section is the technique of choice; it is simple and inexpensive, and it uses ordinary electron microscopes. The resulting pictures reveal a world of complex cell structure and function. These images necessarily change our conception of the cytoskeleton, nuclear matrix, mitosis, and the relation of membranes to cytostructure. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:7777493

  4. Magnetosheath Filamentary Structures

    NASA Astrophysics Data System (ADS)

    Rojas-Castillo, D. I.; Blanco-Cano, X.; Omidi, N.; Kajdic, P.

    2014-12-01

    The terrestrial magnetosheath is full of highly perturbed plasma. The inhomogeneity of this region leads to temperature anisotropies that can originate waves; e.g, mirror mode and ion cyclotron waves. Other structures like the magnetosheath filamentary structures (MFS) can also be present. These are structures reported from results of global hybrid simulations by Omidi et al. (2014) that are formed in the quasi-parallel region of the bow shock and they are convected into the magnetosheath. The MFS are characterized by field aligned enhancements of density and temperature that are anti-correlated. In this work we analyze magnetic field and plasma data from the THEMIS mission to explore the possible existence of MFS.

  5. Underground waste barrier structure

    DOEpatents

    Saha, Anuj J.; Grant, David C.

    1988-01-01

    Disclosed is an underground waste barrier structure that consists of waste material, a first container formed of activated carbonaceous material enclosing the waste material, a second container formed of zeolite enclosing the first container, and clay covering the second container. The underground waste barrier structure is constructed by forming a recessed area within the earth, lining the recessed area with a layer of clay, lining the clay with a layer of zeolite, lining the zeolite with a layer of activated carbonaceous material, placing the waste material within the lined recessed area, forming a ceiling over the waste material of a layer of activated carbonaceous material, a layer of zeolite, and a layer of clay, the layers in the ceiling cojoining with the respective layers forming the walls of the structure, and finally, covering the ceiling with earth.

  6. Modular arctic structures system

    SciTech Connect

    Reusswig, G. H.

    1984-12-04

    A modular and floatable offshore exploration and production platform system for use in shallow arctic waters is disclosed. A concrete base member is floated to the exploration or production site, and ballated into a predredged cavity. The cavity and base are sized to provide a stable horizontal base 30 feet below the mean water/ice plane. An exploration or production platform having a massive steel base is floated to the site and ballasted into position on the base. Together, the platform, base and ballast provide a massive gravity structure that is capable of resisting large ice and wave forces that impinge on the structure. The steel platform has a sloping hourglass profile to deflect horizontal ice loads vertically, and convert the horizontal load to a vertical tensile stress, which assists in breaking the ice as it advances toward the structure.

  7. [Structural sensitivity analysis].

    PubMed

    Carrera-Hueso, F J; Ramón-Barrios, A

    2011-05-01

    The aim of this study was to perform a structural sensitivity analysis of a decision model and to identify its advantages and limitations. A previously published model of dinoprostone was modified, taking two scenarios into account: eliminating postpartum hemorrhages and including both hemorrhages and uterine hyperstimulation among the adverse effects. The result of the structural sensitivity analysis shows the robustness of the underlying model and confirmed the initial results: the intrauterine device is more cost-effective than intracervical dinoprostone gel. Structural sensitivity analyses should be congruent with the situation studied and clinically validated. Although uncertainty may be only slightly reduced, these analyses provide information and add greater validity and reliability to the model.

  8. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Loewy, R. G.; Wiberley, S. E.

    1981-01-01

    The composite aircraft program component (CAPCOMP) is a graduate level project conducted in parallel with a composite structures program. The composite aircraft program glider (CAPGLIDE) is an undergraduate demonstration project which has as its objectives the design, fabrication, and testing of a foot launched ultralight glider using composite structures. The objective of the computer aided design (COMPAD) portion of the composites project is to provide computer tools for the analysis and design of composite structures. The major thrust of COMPAD is in the finite element area with effort directed at implementing finite element analysis capabilities and developing interactive graphics preprocessing and postprocessing capabilities. The criteria for selecting research projects to be conducted under the innovative and supporting research (INSURE) program are described.

  9. Tendon Structure and Composition.

    PubMed

    Thorpe, Chavaunne T; Screen, Hazel R C

    2016-01-01

    Tendons are soft, fibrous tissues that connect muscle to bone. Their main function is to transfer muscle generated force to the bony skeleton, facilitating movement around a joint, and as such they are relatively passive, inelastic structures, able to resist high forces. Tendons are predominantly composed of collagen, which is arranged in a hierarchical manner parallel to the long axis of the tendon, resulting in high tensile strength. Tendon also contains a range of non-collagenous proteins, present in low amounts, which nevertheless have important functional roles. In this chapter, we describe general tendon composition and structure, and discuss how variations in composition and structure at different levels of the tendon hierarchy confer specific mechanical properties, which are related to tendon function. PMID:27535244

  10. Precision space structures

    NASA Technical Reports Server (NTRS)

    Soosaar, K.

    1985-01-01

    NASA large space structures efforts to date aimed towards large, flexible antenna-like structures (30-100M) with relatively long wavelengths (1-30cm) and moderate disturbances leading to some structure-control interaction. Potential missions in the OPTICS regime require small reflectors/mirrors, short wavelengths (visible to 100 microns), very tight tolerances in surface, alignment, pointing stability, as well as the potential of considerable on-board disturbances. For optics systems: figure/surface control can be quasi-static, active/passive isolation schemes are possible, vibration control is necessary, and the attitude control system can be low BW - Ground testing of reflectors and mirrors is more feasible than with antennas.

  11. Prosodic Structure as a Parallel to Musical Structure.

    PubMed

    Heffner, Christopher C; Slevc, L Robert

    2015-01-01

    What structural properties do language and music share? Although early speculation identified a wide variety of possibilities, the literature has largely focused on the parallels between musical structure and syntactic structure. Here, we argue that parallels between musical structure and prosodic structure deserve more attention. We review the evidence for a link between musical and prosodic structure and find it to be strong. In fact, certain elements of prosodic structure may provide a parsimonious comparison with musical structure without sacrificing empirical findings related to the parallels between language and music. We then develop several predictions related to such a hypothesis. PMID:26733930

  12. Prosodic Structure as a Parallel to Musical Structure

    PubMed Central

    Heffner, Christopher C.; Slevc, L. Robert

    2015-01-01

    What structural properties do language and music share? Although early speculation identified a wide variety of possibilities, the literature has largely focused on the parallels between musical structure and syntactic structure. Here, we argue that parallels between musical structure and prosodic structure deserve more attention. We review the evidence for a link between musical and prosodic structure and find it to be strong. In fact, certain elements of prosodic structure may provide a parsimonious comparison with musical structure without sacrificing empirical findings related to the parallels between language and music. We then develop several predictions related to such a hypothesis. PMID:26733930

  13. [Structural characteristics of Hemiptelea davidii community on Kerqin sandy land].

    PubMed

    Bai, Yun-Peng; Han, Da-Yong; Dong, Yan-Hong; Zhao, Yu-Jing; Li, Jian-Dong

    2008-02-01

    An investigation was made on the species composition and eco-type of Hemiptelea davidii community on Kerqin sandy land. The results showed that in study area, no shrub layer existed in H. davidii forest, while arbor layer could be divided into two sub-layers, with a height of 4.05-7.86 m for the upper layer, and of 2.05-3.20 m for the lower layer. In the community, there were 32 herbal species belonging to 27 genera of 13 families and dominant by Poaceae, Fabaceae and Compositae, and 11 areal types, among which, the species number in Mongolian-Northeastern China-Dahuricia-North China areal type was the highest (34.38%), followed by that in Northeastern China-North China areal type (12.5%). Among three water ecological types, mesophytes occupied 59.37% of the total, and mesoxerophytes and xerophytes occupied 25% and 15.63%, respectively. Hemicryptophytes had a larger amount in six life forms, accounting for 31.25% of the total. H. davidii community had the typical life form characteristics of temperate steppe. PMID:18464628

  14. Nuclear structure research

    NASA Astrophysics Data System (ADS)

    Brenner, D. S.

    1992-07-01

    The TRISTAN on-line isotope separator and the capture gamma ray facility at the HFBR are the experimental foci of the program which has four principal research themes, three involving nuclear structure physics and one directed towards astrophysics. These themes are: (1) the manifestation of the proton-neutron interaction in the evolution of nuclear structure and its relation to collectivity; (2) the appearance and the role of symmetries and supersymmetries in nuclei; (3) the study of new regions of magic nuclei; and (4) the characterization of nuclei important in r-process stellar nucleosynthesis.

  15. Structural dynamics analysis

    NASA Technical Reports Server (NTRS)

    Housner, J. M.; Anderson, M.; Belvin, W.; Horner, G.

    1985-01-01

    Dynamic analysis of large space antenna systems must treat the deployment as well as vibration and control of the deployed antenna. Candidate computer programs for deployment dynamics, and issues and needs for future program developments are reviewed. Some results for mast and hoop deployment are also presented. Modeling of complex antenna geometry with conventional finite element methods and with repetitive exact elements is considered. Analytical comparisons with experimental results for a 15 meter hoop/column antenna revealed the importance of accurate structural properties including nonlinear joints. Slackening of cables in this antenna is also a consideration. The technology of designing actively damped structures through analytical optimization is discussed and results are presented.

  16. Structure of Serum Albumin

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C.; Ho, Joseph X.

    1994-01-01

    Because of its availability, low cost, stability, and unusual ligand-binding properties, serum albumin has been one of the mst extensively studied and applied proteins in biochemistry. However, as a protein, albumin is far from typical, and the widespread interest in and application of albumin have not been balanced by an understanding of its molecular structure. Indeed, for more than 30 years structural information was surmised based solely on techniques such as hydrodynamics, low-angle X-ray scattering, and predictive methods.

  17. Buckling of offshore structures

    SciTech Connect

    Walker, A.C.; Ellinas, C.P.; Supple, W.J.

    1984-01-01

    This new handbook gives detailed design guidance for a wide range of structural components and types of loading related to the buckling of offshore structures. It presents many hundreds of test results that have been examined and collated to give a common base of comparison, and its surveys all the relevant national and international design codes, comparing the relative accuracy of their predictions against the available test results. Contents are: unstiffened cord and bracing elements; ring-stiffened cylinders; stringer-stiffened and orthogonally-stiffened cylinders; flat panels; and end-closures and transition shells.

  18. Composite foam structures

    NASA Technical Reports Server (NTRS)

    Williams, Brian E. (Inventor); Brockmeyer, Jerry (Inventor); Tuffias, Robert H. (Inventor)

    2005-01-01

    A composite rigid foam structure that has a skin or coating on at least one of its surfaces. The skin is formed in situ by thermal spray techniques. The skin is bonded substantially throughout the surface of the porous substrate to the peripheries of the pores. The skin on the average does not penetrate the surface of the substrate by more than the depth of about 2 to 5 pores. Thus, thermal spraying the skin onto the rigid foam produces a composite that is tightly and uniformly bonded together without unduly increasing the weight of the composite structure. Both thermal conductivity and bonding are excellent.

  19. Interest rates hierarchical structure

    NASA Astrophysics Data System (ADS)

    Di Matteo, T.; Aste, T.; Hyde, S. T.; Ramsden, S.

    2005-09-01

    We propose a general method to study the hierarchical organization of financial data by embedding the structure of their correlations in metric graphs in multi-dimensional spaces. An application to two different sets of interest rates is discussed by constructing triangular embeddings on the sphere. Three-dimensional representations of these embeddings with the correct metric geometry are constructed and visualized. The resulting graphs contain the minimum spanning tree as a sub-graph and they preserve its hierarchical structure. This produces a clear cluster differentiation and allows us to compute new local and global topological quantities.

  20. Multiscale structure of meanders

    NASA Astrophysics Data System (ADS)

    Vermeulen, B.; Hoitink, A. J. F.; Zolezzi, G.; Abad, J. D.; Aalto, R.

    2016-04-01

    River meander planforms can be described based on wavelet analysis, but an objective method to identify the main characteristics of a meander planform over all spatial scales is yet to be found. Here we show how a set of simple metrics representing meander shape can be retrieved from a continuous wavelet transform of a planform geometry. We construct a synoptic multiple looping tree to establish the meander structure, revealing the embedding of dominant meander scales in larger-scale loops. The method can be applied beyond the case of rivers to unravel the meandering structure of lava flows, turbidity currents, tidal channels, rivulets, supraglacial streams, and extraterrestrial flows.

  1. Structural mechanics simulations

    NASA Astrophysics Data System (ADS)

    Biffle, Johnny H.

    1992-05-01

    Sandia National Laboratory has a very broad structural capability. Work has been performed in support of reentry vehicles, nuclear reactor safety, weapons systems and components, nuclear waste transport, strategic petroleum reserve, nuclear waste storage, wind and solar energy, drilling technology, and submarine programs. The analysis environment contains both commercial and internally developed software. Included are mesh generation capabilities, structural simulation codes, and visual codes for examining simulation results. To effectively simulate a wide variety of physical phenomena, a large number of constitutive models have been developed.

  2. Objective Eulerian coherent structures.

    PubMed

    Serra, Mattia; Haller, George

    2016-05-01

    We define objective Eulerian Coherent Structures (OECSs) in two-dimensional, non-autonomous dynamical systems as the instantaneously most influential material curves. Specifically, OECSs are stationary curves of the averaged instantaneous material stretching-rate or material shearing-rate functionals. From these objective (frame-invariant) variational principles, we obtain explicit differential equations for hyperbolic, elliptic, and parabolic OECSs. As an illustration, we compute OECSs in an unsteady ocean velocity data set. In comparison to structures suggested by other common Eulerian diagnostic tools, we find OECSs to be the correct short-term cores of observed trajectory deformation patterns. PMID:27249950

  3. Stellar structure of magnetars

    NASA Astrophysics Data System (ADS)

    Dong, JianMin; Zuo, Wei; Gu, JianZhong; Shang, XinLe

    2016-04-01

    Magnetars are strong magnetized neutron stars which could emit quiescent X-ray, repeating burst of soft gamma ray, and even the giant flares. We investigate the effects of magnetic fields on the structure of isolated magnetars. The stellar structure together with the magnetic field configuration can be obtained at the same time within a self-consistent procedure. The magnetar mass and radius are found to be weakly enhanced by the strong magnetic fields. Unlike other previous investigations, the magnetic field is unable to violate the mass limit of the neutron stars.

  4. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Loewy, R. G.; Wiberley, S. E.

    1979-01-01

    A multifaceted program is described in which aeronautical, mechanical, and materials engineers interact to develop composite aircraft structures. Topics covered include: (1) the design of an advanced composite elevator and a proposed spar and rib assembly; (2) optimizing fiber orientation in the vicinity of heavily loaded joints; (3) failure mechanisms and delamination; (4) the construction of an ultralight sailplane; (5) computer-aided design; finite element analysis programs, preprocessor development, and array preprocessor for SPAR; (6) advanced analysis methods for composite structures; (7) ultrasonic nondestructive testing; (8) physical properties of epoxy resins and composites; (9) fatigue in composite materials, and (10) transverse thermal expansion of carbon/epoxy composites.

  5. Practical structured illumination microscopy.

    PubMed

    Rego, E Hesper; Shao, Lin

    2015-01-01

    Structured illumination microscopy (SIM) is a method that can double the spatial resolution of wide-field fluorescence microscopy in three dimensions by using spatially structured illumination light. In this chapter, we introduce the basic principles of SIM and describe in detail several different implementations based on either a diffraction grating or liquid crystal spatial light modulators. We also describe nonlinear SIM, a method that in theory can achieve unlimited resolution. In addition, we discuss a number of key points important for high-resolution imaging. PMID:25391800

  6. Structural mechanics simulations

    NASA Technical Reports Server (NTRS)

    Biffle, Johnny H.

    1992-01-01

    Sandia National Laboratory has a very broad structural capability. Work has been performed in support of reentry vehicles, nuclear reactor safety, weapons systems and components, nuclear waste transport, strategic petroleum reserve, nuclear waste storage, wind and solar energy, drilling technology, and submarine programs. The analysis environment contains both commercial and internally developed software. Included are mesh generation capabilities, structural simulation codes, and visual codes for examining simulation results. To effectively simulate a wide variety of physical phenomena, a large number of constitutive models have been developed.

  7. Discovery, structure, function, and applications of cyclotides: circular proteins from plants.

    PubMed

    Weidmann, Joachim; Craik, David J

    2016-08-01

    Cyclotides are plant-derived cyclic peptides that have a head-to-tail cyclic backbone and three conserved disulphide bonds that form a cyclic cystine knot motif. They occur in plants from the Violaceae, Rubiaceae, Cucurbitaceae, Fabaceae, and Solanaceae families, typically with 10-100 cyclotides in a given plant species, in a wide range of tissues, including flowers, leaves, stems, and roots. Some cyclotides are expressed in large amounts (up to 1g kg(-1) wet plant weight) and their natural function appears to be to protect plants from pests or pathogens. This article provides a brief overview of their discovery, distribution in plants, and applications. In particular, their exceptional stability has led to their use as peptide-based scaffolds in drug design applications. They also have potential as natural 'ecofriendly' insecticides, and as protein engineering frameworks. PMID:27222514

  8. Redundant structures at elevated temperatures

    NASA Technical Reports Server (NTRS)

    Guidry, L. I.; Mintz, G. H.

    1980-01-01

    In many structural systems, it is desirable to perform analysis to determine how safe structure is when subjected to "yielding" loads. FRAME1 computer program analyzes, in both plastic and elastic ranges, redundant structures subjected to thermal and mechanical loads.

  9. Fire protection for relocatable structures

    SciTech Connect

    1995-06-01

    This standard supersedes DOE/EV-0043, ``Standard on Fire Protection for Portable Structures.`` It was revised to address the numerous types of relocatable structures, such as trailers, tension-supported structures, and tents being used by DOE and contractors.

  10. Governance Structure: Palomar College.

    ERIC Educational Resources Information Center

    Palomar Coll., San Marcos, CA.

    The governance structure of Palomar College (PC) in San Marcos, California, is defined in the plan described in this document. Introductory material indicates that the plan was designed to provide appropriate representation for each of PC's constituent groups, delineate committee responsibilities and reporting relationships, establish the…

  11. LDR structural experiment definition

    NASA Technical Reports Server (NTRS)

    Russell, R. A.

    1988-01-01

    A system study to develop the definition of a structural flight experiment for a large precision segmented reflector on the Space Station was accomplished by the Boeing Aerospace Company for NASA's Langley Research Center. The objective of the study was to use a Large Deployable Reflector (LDR) baseline configuration as the basis for focusing an experiment definition, so that the resulting accommodation requirements and interface constraints could be used as part of the mission requirements data base for Space Station. The primary objectives of the first experiment are to construct the primary mirror support truss and to determine its structural and thermal characteristics. Addition of an optical bench, thermal shield and primary mirror segments, and alignment of the optical components, would occur on a second experiment. The structure would then be moved to the payload point system for pointing, optical control, and scientific optical measurement for a third experiment. Experiment 1 will deploy the primary support truss while it is attached to the instrument module structure. The ability to adjust the mirror attachment points and to attach several dummy primary mirror segments with a robotic system will also be demonstrated. Experiment 2 will be achieved by adding new components and equipment to experiment one. Experiment 3 will demonstrate advanced control strategies, active adjustment of the primary mirror alignment, and technologies associated with optical sensing.

  12. Whence Structured Propositions?

    ERIC Educational Resources Information Center

    Keller, Lorraine Juliano

    2012-01-01

    This thesis is a critical examination of "Structured Propositionalism" (SP), the view that propositions are complex entities composed of the semantic values of the (meaningful) parts of the sentences that express them. According to SP, propositions have constituents and are individuated by the identity and arrangement of their…

  13. Structural Pest Control.

    ERIC Educational Resources Information Center

    Kahn, M. S.; Hoffman, W. M.

    This manual is designed for those who seek certification as pesticide applicators for industrial, institutional, structural, and health-related pest control. It is divided into six sections covering general pest control, wood-destroying organisms, bird control, fumigation, rodent control, and industrial weed control. The manual gives information…

  14. Emerging Organizational Structures.

    ERIC Educational Resources Information Center

    Carchidi, Daniel M.; Peterson, Marvin W.

    2000-01-01

    Discussion of emerging higher educational organizational structures focuses on the increasing importance of distance education. Considers the emerging organizational landscape, three types of network organizations, six organization archetypes, organizational forms that support distance education, and implications for higher education planners. (DB)

  15. Secondary Structure Switch

    ERIC Educational Resources Information Center

    King, Angela G.

    2006-01-01

    Neurogenerative diseases like Alzheimer's disease and Parkinson's disease involve a transformation between two peptide and protein structures of alpha-helices and beta-sheets, where the peptide backbone can also participate in metal ion binding in addition to histidine residues. However, the complete absence of change in conformation of Coiled…

  16. Chemical structure of interfaces

    NASA Technical Reports Server (NTRS)

    Grunthaner, F. J.

    1985-01-01

    The interfacial structure of silicon/dielectric and silicon/metal systems is particularly amenable to analysis using a combination of surface spectroscopies together with a variety of chemical structures of Si/SiO2, Si/SiO2Si3N4, Si/Si2N2O, Si/SiO2/Al, and Si/Native Oxide interfaces using high resolution (0.350 eV FWHM) X ray photoelectron spectroscopy. The general structure of these dielectric interfaces entails a monolayer chemical transition layer at the Si/dielectric boundary. Amorphous Si substrates show a wide variety of hydrogenated Si and Si(OH) sub x states that are not observed in thermal oxidation of single crystal material. Extended SiO2 layers greater than 8 A in thickness are shown to be stoichiometric SiO2, but to exhibit a wide variety of local network structures. In the nitrogen containing systems, an approach to stoichiometric oxynitride compounds with interesting impurity and electron trapping properties are seen. In native oxides, substantial topographical nonuniformity in oxide thickness and composition are found. Analysis of metal/oxide interfacial layers is accomplished by analytical removal of the Si substrate by UHV XeF2 dry etching methods.

  17. Electrodes with fiber structure

    NASA Technical Reports Server (NTRS)

    Benczur-Uermoessy, G.; Berger, G.; Haschka, F.

    1986-01-01

    An electrode framework with a fiber structure, universally applicable in alkaline storage battery systems, was developed and readied for production. Storage batteries with these electrodes present higher energy and power densities and are economical to produce. The design is applicable to all rechargable storage batteries and might replace the previous variety of designs.

  18. Manipulating Combinatorial Structures.

    ERIC Educational Resources Information Center

    Labelle, Gilbert

    This set of transparencies shows how the manipulation of combinatorial structures in the context of modern combinatorics can easily lead to interesting teaching and learning activities at every level of education from elementary school to university. The transparencies describe: (1) the importance and relations of combinatorics to science and…

  19. Simulation of phase structures

    SciTech Connect

    Lawson, J.

    1995-04-20

    This memo outlines a procedure developed by the author to extract information from phase measurements and produce a simulated phase structure for use in modeling optical systems, including characteristic optics for the Beamlet and NIF laser systems. The report includes an IDL program listing.

  20. Visual Narrative Structure

    ERIC Educational Resources Information Center

    Cohn, Neil

    2013-01-01

    Narratives are an integral part of human expression. In the graphic form, they range from cave paintings to Egyptian hieroglyphics, from the Bayeux Tapestry to modern day comic books (Kunzle, 1973; McCloud, 1993). Yet not much research has addressed the structure and comprehension of narrative images, for example, how do people create meaning out…

  1. Structured FORTRAN preprocessor

    NASA Technical Reports Server (NTRS)

    Austin, S.; Buckles, B.; Ryan, J. P.

    1980-01-01

    Structured-programming features simplify software design. Programmer needs only few control statements to code program in format easy to debug and maintain, freeing him/her from flow constraints of standard FORTRAN. Program is written in ANSI FORTRAN and is compatible with machine supporting FORTRAN compiler that accepts ANSI statements. It has been implemented on IBM 370.

  2. Structured Mechanical Collage.

    PubMed

    Huang, Zhe; Wang, Jiang; Fu, Hongbo; Lau, Rynson W H

    2014-07-01

    We present a method to build 3D structured mechanical collages consisting of numerous elements from the database given artist-designed proxy models. The construction is guided by some graphic design principles, namely unity, variety and contrast. Our results are visually more pleasing than previous works as confirmed by a user study.

  3. Structured Programming: An Introduction.

    ERIC Educational Resources Information Center

    Moulton, Peter

    Designed for use by computer programming teachers, this booklet presents the concepts of structured programming and provides examples of how to implement this methodology, which provides a systematic way of organizing programs so that even large and complex programs are easier to understand and modify than unstructured programs. After a brief…

  4. Housing And Mounting Structure

    DOEpatents

    Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R.F.; Bryan, Robert P.; Carson, Richard F.; Duckett, III, Edwin B.; McCormick, Frederick B.; Miller, Gregory V.; Peterson, David W.; Smith, Terrance T.

    2005-03-08

    This invention relates to an optical transmitter, receiver or transceiver module, and more particularly, to an apparatus for connecting a first optical connector to a second optical connector. The apparatus comprises: (1) a housing having at least a first end and at least a second end, the first end of the housing capable of receiving the first optical connector, and the second end of the housing capable of receiving the second optical connector; (2) a longitudinal cavity extending from the first end of the housing to the second end of the housing; and (3) an electromagnetic shield comprising at least a portion of the housing. This invention also relates to an apparatus for housing a flexible printed circuit board, and this apparatus comprises: (1) a mounting structure having at least a first surface and a second surface; (2) alignment ridges along the first and second surfaces of the mounting structure, the alignment ridges functioning to align and secure a flexible printed circuit board that is wrapped around and attached to the first and second surfaces of the mounting structure; and (3) a series of heat sink ridges adapted to the mounting structure, the heat sink ridges functioning to dissipate heat that is generated from the flexible printed circuit board.

  5. LDR structural experiment definition

    NASA Technical Reports Server (NTRS)

    Russell, Richard A.; Gates, Richard M.

    1988-01-01

    A study was performed to develop the definition of a structural flight experiment for a large precision segmented reflector that would utilize the Space Station. The objective of the study was to use the Large Deployable Reflector (LDR) baseline configuration for focusing on experiment definition activity which would identify the Space Station accommodation requirements and interface constraints. Results of the study defined three Space Station based experiments to demonstrate the technologies needed for an LDR type structure. The basic experiment configurations are the same as the JPL baseline except that the primary mirror truss is 10 meters in diameter instead of 20. The primary objectives of the first experiment are to construct the primary mirror support truss and to determine its structural and thermal characteristics. Addition of the optical bench, thermal shield and primary mirror segments and alignment of the optical components occur on the second experiment. The structure will then be moved to the payload pointing system for pointing, optical control and scientific optical measurement for the third experiment.

  6. The Structured Classroom

    ERIC Educational Resources Information Center

    Ljusberg, Anna-Lena

    2011-01-01

    The aim of this article is to highlight the organisation of the remedial classroom. The data were collected from observations and semi-structured interviews with 10 teachers in remedial classes for children seen and treated as having concentration deficits. The teachers use primarily compensatory language that places the deficits in the pupils.…

  7. Some Structural Ambiguities.

    ERIC Educational Resources Information Center

    Stageberg, Norman C.

    1958-01-01

    The identification and study of 20 syntactical patterns responsible for much of the structural ambiguity found in literary composition can develop in students an audience awareness. When they realize that such constructions as "a dull boy's knife" and "the club will be open to members from Monday to Thursday" can be misinterpreted, they take more…

  8. Electromagnetic structure of nuclei

    SciTech Connect

    Arnold, R.G.

    1986-07-01

    A brief review is given of selected topics in the electromagnetic structure of nucleons and nuclei, including nucleon form factors from both quantum chromodynamics and electron scattering data, measurements of the deuteron and triton form factors, quasi-elastic scattering, and the EMC effect. 47 refs., 13 figs. (LEW)

  9. Structured and Unstructured Learning.

    ERIC Educational Resources Information Center

    1996

    This document contains four papers presented at a sympoisum on structured and unstructured learning moderated by Catherine Sleezer at the 1996 conference of the Academy of Human Resource Development (AHRD). "Designing Experiential Learning into Organizational Work Life: Proposing a Framework for Theory and Research" (Cheri Maben-Crouch) proposes a…

  10. Structural model of channelrhodopsin.

    PubMed

    Watanabe, Hiroshi C; Welke, Kai; Schneider, Franziska; Tsunoda, Satoshi; Zhang, Feng; Deisseroth, Karl; Hegemann, Peter; Elstner, Marcus

    2012-03-01

    Channelrhodopsins (ChRs) are light-gated cation channels that mediate ion transport across membranes in microalgae (vectorial catalysis). ChRs are now widely used for the analysis of neural networks in tissues and living animals with light (optogenetics). For elucidation of functional mechanisms at the atomic level, as well as for further engineering and application, a detailed structure is urgently needed. In the absence of an experimental structure, here we develop a structural ChR model based on several molecular computational approaches, capitalizing on characteristic patterns in amino acid sequences of ChR1, ChR2, Volvox ChRs, Mesostigma ChR, and the recently identified ChR of the halophilic alga Dunaliella salina. In the present model, we identify remarkable structural motifs that may explain fundamental electrophysiological properties of ChR2, ChR1, and their mutants, and in a crucial validation of the model, we successfully reproduce the excitation energy predicted by absorption spectra. PMID:22241469

  11. Quark structure of nuclei

    SciTech Connect

    Blankenbecler, R.

    1981-01-01

    A brief review is given of selected topics involved in the relativistic quark structure of nuclei such as the infinite momentum variables, scaling variables, counting rules, forward-backward variables, thermodynamic-like limit, QCD effects, higher quark bags, confinement, and many unanswered questions.

  12. Structuralism and the Classroom.

    ERIC Educational Resources Information Center

    Beer, Norman

    1983-01-01

    Argues that structuralism needs to be given a wider base than that of the highly specialized studies that are usually cited as examples. Rather, extension should be made philosophically, in the direction of phenomenology, and, practically, with some of the work being done in linguistics. (HOD)

  13. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Wiberley, S. E.

    1978-01-01

    The purpose of the RPI composites program is to develop advanced technology in the areas of physical properties, structural concepts and analysis, manufacturing, reliability and life prediction. Concommitant goals are to educate engineers to design and use composite materials as normal or conventional materials. A multifaceted program was instituted to achieve these objectives.

  14. Design oriented structural analysis

    NASA Technical Reports Server (NTRS)

    Giles, Gary L.

    1994-01-01

    Desirable characteristics and benefits of design oriented analysis methods are described and illustrated by presenting a synoptic description of the development and uses of the Equivalent Laminated Plate Solution (ELAPS) computer code. ELAPS is a design oriented structural analysis method which is intended for use in the early design of aircraft wing structures. Model preparation is minimized by using a few large plate segments to model the wing box structure. Computational efficiency is achieved by using a limited number of global displacement functions that encompass all segments over the wing planform. Coupling with other codes is facilitated since the output quantities such as deflections and stresses are calculated as continuous functions over the plate segments. Various aspects of the ELAPS development are discussed including the analytical formulation, verification of results by comparison with finite element analysis results, coupling with other codes, and calculation of sensitivity derivatives. The effectiveness of ELAPS for multidisciplinary design application is illustrated by describing its use in design studies of high speed civil transport wing structures.

  15. Structured Sensory Trauma Interventions

    ERIC Educational Resources Information Center

    Steele, William; Kuban, Caelan

    2010-01-01

    This article features the National Institute of Trauma and Loss in Children (TLC), a program that has demonstrated via field testing, exploratory research, time series studies, and evidence-based research studies that its Structured Sensory Intervention for Traumatized Children, Adolescents, and Parents (SITCAP[R]) produces statistically…

  16. Acicular photomultiplier photocathode structure

    DOEpatents

    Craig, Richard A.; Bliss, Mary

    2003-09-30

    A method and apparatus for increasing the quantum efficiency of a photomultiplier tube by providing a photocathode with an increased surface-to-volume ratio. The photocathode includes a transparent substrate, upon one major side of which is formed one or more large aspect-ratio structures, such as needles, cones, fibers, prisms, or pyramids. The large aspect-ratio structures are at least partially composed of a photoelectron emitting material, i.e., a material that emits a photoelectron upon absorption of an optical photon. The large aspect-ratio structures may be substantially composed of the photoelectron emitting material (i.e., formed as such upon the surface of a relatively flat substrate) or be only partially composed of a photoelectron emitting material (i.e., the photoelectron emitting material is coated over large aspect-ratio structures formed from the substrate material itself.) The large aspect-ratio nature of the photocathode surface allows for an effective increase in the thickness of the photocathode relative the absorption of optical photons, thereby increasing the absorption rate of incident photons, without substantially increasing the effective thickness of the photocathode relative the escape incidence of the photoelectrons.

  17. Freedom Is Structure.

    ERIC Educational Resources Information Center

    Papay, Twila Yates

    To make freedom work in the writing classroom, the instructor must be highly structured, possessing a clear sense of direction that includes a precise idea of the skills to be covered. Freedom refers to the view of writing as a liberal art, a liberating force with the capacity to open new channels of thought and lead students to discover…

  18. Imprinting artificial magnetic structures.

    SciTech Connect

    Lohstroh, W.

    1998-09-25

    Recently we created La/Fe multilayers with a helical magnetic structure imprinted from the conditions of growth rather than by the magnetic interactions between layers. Each sublayer was 30{angstrom} thick, and during deposition the sample was rotated in an external field of 3 Oe. a field strong enough to magnetize the Fe layer being deposited but not sufficient to perturb the magnetization of the Fe layers already grown. As a result adjacent Fe layers formed a helical structure with a chirality and periodicity determined by the rotational direction and speed of the substrate and the rate of deposition. Following this discovery, an extensive set of experiments (mainly using Kerr effect magnetometry and polarized neutron reflectivity) was undertaken to ascertain the stability of imprinted magnetic structures, and to understand the onset of magnetization during growth. La/Fe imprinted helical magnetic structures (of different La and Fe thicknesses) were found to be stable in time and to be permanently erased only by magnetic fields larger than 90 Oe.

  19. Solid electrolyte structure

    DOEpatents

    Fraioli, Anthony V.

    1984-01-01

    A solid electrolyte structure for fuel cells and other electrochemical devices providing oxygen ion transfer by a multiplicity of exposed internal surfaces made of a composition containing an oxide of a multivalent transition metal and forming small pore-like passages sized to permit oxygen ion transfer while limiting the transfer of oxygen gas.

  20. Air Structures: Inflatable Alternatives

    ERIC Educational Resources Information Center

    Valerio, Joseph M.; And Others

    1973-01-01

    Describes and evaluates several avant garde'' examples of air structures. Included are a soft'' child's playpen, a pneudome that employs a water ballast for anchoring, a one-acre enclosed campus, an instant city'' constructed for an industrial design conference, and the Fuji Pavilion, at Expo '70 in Osaka, Japan, that was large enough to cover…

  1. Science as Structured Imagination

    ERIC Educational Resources Information Center

    De Cruz, Helen; De Smedt, Johan

    2010-01-01

    This paper offers an analysis of scientific creativity based on theoretical models and experimental results of the cognitive sciences. Its core idea is that scientific creativity--like other forms of creativity--is structured and constrained by prior ontological expectations. Analogies provide scientists with a powerful epistemic tool to overcome…

  2. Large, Easily Deployable Structures

    NASA Technical Reports Server (NTRS)

    Agan, W. E.

    1983-01-01

    Study of concepts for large space structures will interest those designing scaffolding, radio towers, rescue equipment, and prefabricated shelters. Double-fold, double-cell module was selected for further design and for zero gravity testing. Concept is viable for deployment by humans outside space vehicle as well as by remotely operated manipulator.

  3. Structural Equation Model Trees

    ERIC Educational Resources Information Center

    Brandmaier, Andreas M.; von Oertzen, Timo; McArdle, John J.; Lindenberger, Ulman

    2013-01-01

    In the behavioral and social sciences, structural equation models (SEMs) have become widely accepted as a modeling tool for the relation between latent and observed variables. SEMs can be seen as a unification of several multivariate analysis techniques. SEM Trees combine the strengths of SEMs and the decision tree paradigm by building tree…

  4. Teaching Structure in Algebra

    ERIC Educational Resources Information Center

    Merlin, Ethan M.

    2013-01-01

    This article describes how the author has developed tasks for students that address the missed "essence of the matter" of algebraic transformations. Specifically, he has found that having students practice "perceiving" algebraic structure--by naming the "glue" in the expressions, drawing expressions using…

  5. Cell Structure Study.

    ERIC Educational Resources Information Center

    Ekstrom, James V.

    2000-01-01

    Presents an activity in which students use microscopes and digital images to examine Elodea, a fresh water plant, before and after the process of plasmolysis, identify plant cellular structures before and after plasmolysis, and calculate the size of the plant's vacuole. (ASK)

  6. Control Augmented Structural Synthesis

    NASA Technical Reports Server (NTRS)

    Lust, Robert V.; Schmit, Lucien A.

    1988-01-01

    A methodology for control augmented structural synthesis is proposed for a class of structures which can be modeled as an assemblage of frame and/or truss elements. It is assumed that both the plant (structure) and the active control system dynamics can be adequately represented with a linear model. The structural sizing variables, active control system feedback gains and nonstructural lumped masses are treated simultaneously as independent design variables. Design constraints are imposed on static and dynamic displacements, static stresses, actuator forces and natural frequencies to ensure acceptable system behavior. Multiple static and dynamic loading conditions are considered. Side constraints imposed on the design variables protect against the generation of unrealizable designs. While the proposed approach is fundamentally more general, here the methodology is developed and demonstrated for the case where: (1) the dynamic loading is harmonic and thus the steady state response is of primary interest; (2) direct output feedback is used for the control system model; and (3) the actuators and sensors are collocated.

  7. Data Structures and Algorithms.

    ERIC Educational Resources Information Center

    Wirth, Niklaus

    1984-01-01

    Built-in data structures are the registers and memory words where binary values are stored; hard-wired algorithms are the fixed rules, embodied in electronic logic circuits, by which stored data are interpreted as instructions to be executed. Various topics related to these two basic elements of every computer program are discussed. (JN)

  8. Probabilistic Structural Analysis Program

    NASA Technical Reports Server (NTRS)

    Pai, Shantaram S.; Chamis, Christos C.; Murthy, Pappu L. N.; Stefko, George L.; Riha, David S.; Thacker, Ben H.; Nagpal, Vinod K.; Mital, Subodh K.

    2010-01-01

    NASA/NESSUS 6.2c is a general-purpose, probabilistic analysis program that computes probability of failure and probabilistic sensitivity measures of engineered systems. Because NASA/NESSUS uses highly computationally efficient and accurate analysis techniques, probabilistic solutions can be obtained even for extremely large and complex models. Once the probabilistic response is quantified, the results can be used to support risk-informed decisions regarding reliability for safety-critical and one-of-a-kind systems, as well as for maintaining a level of quality while reducing manufacturing costs for larger-quantity products. NASA/NESSUS has been successfully applied to a diverse range of problems in aerospace, gas turbine engines, biomechanics, pipelines, defense, weaponry, and infrastructure. This program combines state-of-the-art probabilistic algorithms with general-purpose structural analysis and lifting methods to compute the probabilistic response and reliability of engineered structures. Uncertainties in load, material properties, geometry, boundary conditions, and initial conditions can be simulated. The structural analysis methods include non-linear finite-element methods, heat-transfer analysis, polymer/ceramic matrix composite analysis, monolithic (conventional metallic) materials life-prediction methodologies, boundary element methods, and user-written subroutines. Several probabilistic algorithms are available such as the advanced mean value method and the adaptive importance sampling method. NASA/NESSUS 6.2c is structured in a modular format with 15 elements.

  9. Composite structural materials

    NASA Technical Reports Server (NTRS)

    Ansell, G. S.; Loewy, R. G.; Wiberley, S. E.

    1982-01-01

    Research in the basic composition, characteristics, and processng science of composite materials and their constituents is balanced against the mechanics, conceptual design, fabrication, and testing of generic structural elements typical of aerospace vehicles so as to encourage the discovery of unusual solutions to problems. Detailed descriptions of the progress achieved in the various component parts of his program are presented.

  10. LUTE telescope structural design

    NASA Technical Reports Server (NTRS)

    Ruthven, Gregory

    1993-01-01

    The major objective of the Lunar Ultraviolet Transit Experiment (LUTE) Telescope Structural Design Study was to investigate the feasibility of designing an ultralightweight 1-m aperture system within optical performance requirements and mass budget constraints. This study uses the results from our previous studies on LUTE as a basis for further developing the LUTE structural architecture. After summarizing our results in Section 2, Section 3 begins with the overall logic we used to determine which telescope 'structural form' should be adopted for further analysis and weight estimates. Specific telescope component analysis showing calculated fundamental frequencies and how they compare with our derived requirements are included. 'First-order' component stress analyses to ensure telescope optical and structural component (i.e. mirrors & main bulkhead) weights are realistic are presented. Layouts of both the primary and tertiary mirrors showing dimensions that are consistent with both our weight and frequency calculations also form part of Section 3. Section 4 presents our calculated values for the predicted thermally induced primary-to-secondary mirror despace motion due to the large temperature range over which LUTE must operate. Two different telescope design approaches (one which utilizes fused quartz metering rods and one which assumes the entire telescope is fabricated from beryllium) are considered in this analysis. We bound the secondary mirror focus mechanism range (in despace) based on these two telescope configurations. In Section 5 we show our overall design of the UVTA (Ultraviolet Telescope Assembly) via an 'exploded view' of the sub-system. The 'exploded view' is annotated to help aid in the understanding of each sub-assembly. We also include a two view layout of the UVTA from which telescope and telescope component dimensions can be measured. We conclude our study with a set of recommendations not only with respect to the LUTE structural architecture

  11. Structural Dynamics and Control Interaction of Flexible Structures

    NASA Technical Reports Server (NTRS)

    Ryan, Robert S. (Editor); Scofield, Harold N. (Editor)

    1987-01-01

    A workshop on structural dynamics and control interaction of flexible structures was held to promote technical exchange between the structural dynamics and control disciplines, foster joint technology, and provide a forum for discussing and focusing critical issues in the separate and combined areas. Issues and areas of emphasis were identified in structure-control interaction for the next generation of flexible systems.

  12. Improving RNA secondary structure prediction with structure mapping data.

    PubMed

    Sloma, Michael F; Mathews, David H

    2015-01-01

    Methods to probe RNA secondary structure, such as small molecule modifying agents, secondary structure-specific nucleases, inline probing, and SHAPE chemistry, are widely used to study the structure of functional RNA. Computational secondary structure prediction programs can incorporate probing data to predict structure with high accuracy. In this chapter, an overview of current methods for probing RNA secondary structure is provided, including modern high-throughput methods. Methods for guiding secondary structure prediction algorithms using these data are explained, and best practices for using these data are provided. This chapter concludes by listing a number of open questions about how to best use probing data, and what these data can provide.

  13. Lewis Structures Technology, 1988. Volume 2: Structural Mechanics

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Lewis Structures Div. performs and disseminates results of research conducted in support of aerospace engine structures. These results have a wide range of applicability to practitioners of structural engineering mechanics beyond the aerospace arena. The engineering community was familiarized with the depth and range of research performed by the division and its academic and industrial partners. Sessions covered vibration control, fracture mechanics, ceramic component reliability, parallel computing, nondestructive evaluation, constitutive models and experimental capabilities, dynamic systems, fatigue and damage, wind turbines, hot section technology (HOST), aeroelasticity, structural mechanics codes, computational methods for dynamics, structural optimization, and applications of structural dynamics, and structural mechanics computer codes.

  14. Lewis Structures Technology, 1988. Volume 1: Structural Dynamics

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The specific purpose of the symposium was to familiarize the engineering structures community with the depth and range of research performed by the Structures Division of the Lewis Research Center and its academic and industrial partners. Sessions covered vibration control, fracture mechanics, ceramic component reliability, parallel computing, nondestructive testing, dynamical systems, fatigue and damage, wind turbines, hot section technology, structural mechanics codes, computational methods for dynamics, structural optimization, and applications of structural dynamics.

  15. A new biflavonyloxymethane from Pongamia pinnata.

    PubMed

    Ghosh, Anindita; Mandal, Suvra; Banerji, Avijit; Banerji, Julie

    2010-08-01

    The root bark of Pongamia pinnata Pierre Syn Pongamia glabra (Family: Fabaceae) has afforded a new biflavonyloxymethane, karanjabiflavone, along with a known furanoflavone, pongapin. The structure of this new biflavonyloxymethane was elucidated from extensive spectral studies including 2D-NMR experiments. Both of these compounds possess antioxidant activity. PMID:20839621

  16. Medicago truncatula-derived calcium oxalate crystals have a negative impact on chewing insect performance via their physical properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant structural traits often act as defenses against herbivorous insects, causing them to avoid feeding on a given plant or tissue. Mineral crystals of calcium oxalate in Medicago truncatula Gaertn. (Fabaceae) leaves have previously been shown to be effective deterrents of lepidopteran insect feedi...

  17. Neuroprotective and nootropic activity of Clitorea ternatea Linn.(Fabaceae) leaves on diabetes induced cognitive decline in experimental animals

    PubMed Central

    Talpate, Karuna A.; Bhosale, Uma A.; Zambare, Mandar R.; Somani, Rahul S

    2014-01-01

    Purpose: Ethanol extract of Clitorea ternatea (EECT) was evaluated in diabetes-induced cognitive decline rat model for its nootropic and neuroprotective activity. Materials and Methods: Effect on spatial working memory, spatial reference memory and spatial working-reference memory was evaluated by Y maze, Morris water maze and Radial arm maze respectively. Neuroprotective effects of EECT was studied by assaying acetylcholinesterase, lipid peroxide, superoxide dismutase (SOD), total nitric oxide (NO), catalase (CAT) and glutathione (GSH) levels in the brain of diabetic rats. Results: The EECT (200 and 400 mg/kg) was found to cause significant increase in spatial working memory (P < 0.05), spatial reference memory (P < 0.001) and spatial working-reference (P < 0.001) in retention trials on Y maze, Morris water maze and Radial arm maze respectively. Whereas significant decrease in acetylcholinesterase activity (P < 0.05), lipid peroxide (P < 0.001), total NO (P < 0.001) and significant increase in SOD, CAT and GSH levels was observed in animals treated with EECT (200 and 400 mg/kg) compared to diabetic control group. Conclusions: The present data indicates that Clitorea ternatea tenders protection against diabetes induced cognitive decline and merits the need for further studies to elucidate its mode of action. PMID:24459404

  18. The invasive species Ulex europaeus (Fabaceae) shows high dynamism in a fragmented landscape of south-central Chile.

    PubMed

    Altamirano, Adison; Cely, Jenny Paola; Etter, Andrés; Miranda, Alejandro; Fuentes-Ramirez, Andres; Acevedo, Patricio; Salas, Christian; Vargas, Rodrigo

    2016-08-01

    Ulex europaeus (gorse) is an invasive shrub deemed as one of the most invasive species in the world. U. europaeus is widely distributed in the south-central area of Chile, which is considered a world hotspot for biodiversity conservation. In addition to its negative effects on the biodiversity of natural ecosystems, U. europaeus is one of the most severe pests for agriculture and forestry. Despite its importance as an invasive species, U. europaeus has been little studied. Although information exists on the potential distribution of the species, the interaction of the invasion process with the spatial dynamic of the landscape and the landscape-scale factors that control the presence or absence of the species is still lacking. We studied the spatial and temporal dynamics of the landscape and how these relate to U. europaeus invasion in south-central Chile. We used supervised classification of satellite images to determine the spatial distribution of the species and other land covers for the years 1986 and 2003, analysing the transitions between the different land covers. We used logistic regression for modelling the increase, decrease and permanence of U. europaeus invasion considering landscape variables. Results showed that the species covers only around 1 % of the study area and showed a 42 % reduction in area for the studied period. However, U. europaeus was the cover type which presented the greatest dynamism in the landscape. We found a strong relationship between changes in land cover and the invasion process, especially connected with forest plantations of exotic species, which promotes the displacement of U. europaeus. The model of gorse cover increase presented the best performance, and the most important predictors were distance to seed source and landscape complexity index. Our model predicted high spread potential of U. europaeus in areas of high conservation value. We conclude that proper management for this invasive species must take into account the spatial dynamics of the landscape within the invaded area in order to address containment, control or mitigation of the invasion. PMID:27473109

  19. Heterogeneity of terrestrial bromeliad colonies and regeneration of Acacia praecox (Fabaceae) in a humid-subtropical-Chaco forest, Argentina.

    PubMed

    Barberis, Ignacio M; Lewis, Juan Pablo

    2005-01-01

    In several tropical and subtropical forests, plants of the understorey act as an ecological filter that differentially affects woody species regeneration. In convex sectors of the Schinopsis balansae (Anacardiaceae) forests of the Southeastern Chaco there are dense colonies of terrestrial bromeliads. These may influence forest regeneration by intercepting rain water and propagules in their tanks. Within colonies, the spatial distribution of bromeliads is clumped because their clonal growth leaves numerous internal gaps. In this study we describe the internal heterogeneity of three bromeliad colonies (plots) and analyze how this heterogeneity affects Acacia praecox regeneration (i.e. seedling recruitment and survival). In January 1996, we randomly placed three transects with 150 contiguous quadrats of 100 cm(2) in each plot. For each quadrat we recorded the type of floor cover (i.e. bromeliads, herbs, litter, or bare soil) and the presence of A. praecox seeds or seedlings. In July 1996 we relocated the transects and recorded seedling survival. Bromeliad colonies showed a high internal heterogeneity. Almost half of the 450 quadrats were covered by two terrestrial bromeliads. Aechmea distichantha was recorded in 81% of all quadrats with bromeliads, and Bromelia serra in the others. All quadrats with bromeliads were covered by litter. Half of them were occupied by the bases of bromeliads and the others were covered by their leaves. In contrast, where bromeliads were not present, soil surface was covered by litter in 83% and by herbaceous vegetation in 11% of the quadrats; very few quadrats were covered by bare soil. In January 1996, we recorded 127 seeds and 176 seedlings of A. praecox. Seed and seedling densities of A. praecox were similar in quadrats with and without bromeliads, but variability in seedling density of A. praecox was higher within than among plots. Seed density was higher in quadrats covered by bromeliad leaves than inside the tanks. Seedling survival of A. praecox was slightly higher in quadrats with bromeliads in only one of the three plots. No seedling survived inside the bromeliad tanks. Apparently. bromeliad colonies have no effect on seedling regeneration of A. praecox.

  20. Genome-wide identification and evolutionary analysis of nucleotide-binding site-encoding resistance genes in Lotus japonicus (Fabaceae).

    PubMed

    Song, H; Wang, P F; Li, T T; Xia, H; Zhao, S Z; Hou, L; Zhao, C Z

    2015-01-01

    Nucleotide-binding site (NBS) disease resistance genes play a crucial role in plant defense responses against pathogens and insect pests. Many NBS-encoding genes have been detected in Lotus japonicus, an important forage crop in many parts of the world. However, most NBS genes identified so far in L. japonicus were only partial sequences. We identified 45 full-length NBS-encoding genes in the L. japonicus genome, and analyzed gene duplications, motifs, and the molecular phylogeny to further understand the NBS gene family. We found that gene duplication events rarely occur in L. japonicus NBS-encoding (LjNBS) genes. In addition, LjNBS genes were subjected to selection pressure, and codon usage bias was evident. We tested for purifying selection (specifically in the CC-NBS-LRR and TIR-NBS-LRR groups), and found strong purifying selection in the TIR-domain-containing sequences, indicating that the CC-NBS-LRR group is more likely to undergo expansion than the TIR-NBS-LRR group. Moreover, our results showed that both selection and mutation contributed to LjNBS codon usage bias, but mutational bias was the major influence on codon usage.

  1. A postmenopause-like model of ovariectomized Wistar rats to identify active principles of Erythrina lysistemon (Fabaceae).

    PubMed

    Mvondo, M A; Njamen, D; Fomum, S Tanee; Wandji, J; Vollmer, Günter

    2011-10-01

    To determine whether the two major compounds of Erythrina lysistemon are active principles accounting for Erythrina estrogenic effects, we used a postmenopause-like model of ovariectomized Wistar rats to evaluate their effects on some menopausal problems. Ovariectomized rats were orally treated either with compound 1 or compound 2 at 1 and 10 mg/kg BW for 28 days. Estradiol valerate served as the reference substance. As results, compounds 1 and 2 displayed estrogen-like effects on the uterus and the vagina, and reduced atherogenic risks by decreasing the two assessed atherogenic parameters, the total cholesterol/HDL-cholesterol ratio and the atherogenic index of plasma.

  2. Microsatellite markers for the Cabreúva tree, Myroxylon peruiferum (Fabaceae), an endangered medicinal species from the Brazilian Atlantic Forest.

    PubMed

    Schwarcz, K D; Bajay, M M; Macrini, C M T; Salazar, V L P; Souza, A P; Pinheiro, J B; Brancalion, P H S; Rodrigues, R R; Zucchi, M I

    2014-01-01

    The Cabreúva tree, Myroxylon peruiferum, is an endangered tropical species from Brazil used in forest restoration projects. It is known for its medicinal properties. Eleven microsatellite markers were developed for this species, from a microsatellite-enriched library. Nine of these markers, characterized in 30 individuals from a semideciduous forest remnant population in southeast Brazil, were polymorphic, with allele numbers ranging from 2 to 8 per locus; expected and observed heterozygosities ranged from 0.103 to 0.757 and 0.107 to 0.704, respectively. One locus (Mpe-C04) showed significant deviation from Hardy-Weinberg equilibrium, probably due to null alleles. Two other loci (Mpe-E09 and Mpe-H07) were monomorphic in this population. These microsatellite loci should be useful for future population genetic studies of this species.

  3. Psoralea diturnerae and P. vanberkelae (Psoraleeae, Fabaceae): two new species restricted to the Core Cape Region of South Africa

    PubMed Central

    Bello, Abubakar; Stirton, Charles H.; Chimphango, Samson B.M.; Muasya, A. Muthama

    2015-01-01

    Abstract Two new species of Psoralea L. are described: Psoralea diturnerae A. Bello, C.H. Stirt. & Muasya, sp. nov. and Psoralea vanberkelae C.H. Stirt., A. Bello & Muasya, sp. nov. Psoralea diturnerae is endemic to the Outeniqua mountains (Camferskloof) and is characterised by a mass of numerous basal shoots out of which emerge 2–3 woody stems up to 2 m tall, 3-foliolate needle-like leaflets at the base of the seasonally growing shoot reducing to one towards the apex and bearing numerous 1–3-flowered axillary inflorescences along its length; each mauve to purple and white flower subtended by a trifid cupulum. Psoralea vanberkelae is characterised by its spreading mounding habit, short tightly packed fleshy leaves, with large impressed papillae, densely glandular short broadly triangular stipules, pale to intense mauve to deep blue flowers, standard with a dark purple central blotch above a M-shaped white patch situated above claw, and khaki seeds with purple flecks. PMID:25698896

  4. Antiproliferative action of aqueous extracts of Hymenaea stigonocarpa Mart. (Fabaceae) on the cell cycle of Allium cepa L.

    PubMed

    Lacerda, Lourran P; Malaquias, Geiz; Peron, Ana Paula

    2014-09-01

    In this study we evaluated the action of crude aqueous extracts obtained from rhytidome of Hymenaea stigonocarpa (jatobá-do-cerrado) on Allium cepa meristematic root cells in three concentrations: 0.082, 0.164, 0.328g/mL, at exposure times of 24 and 48 h. The slides were prepared by the crushing technique, and cells analyzed throughout the cell cycle, totaling 5000 for each control group and concentration. It was found that all three concentrations, including the lowest which is considered ideal for use, in all exposure times, had significant antiproliferative action on the cell cycle of this test system. For cells under division, we observed a high number of cells in prophase. Therefore, under the conditions studied H. stigonocarpa indicated to be cytotoxic. PMID:25029361

  5. Protective role of Ginkgo biloba on petroleum wastewater-induced toxicity in Vicia faba L. (Fabaceae) root tip cells.

    PubMed

    Cavusoglu, Kultigin; Yapar, Kursad; Kinalioglu, Kadir; Turkmen, Zafer; Cavusoglu, Kursat; Yalcin, Emine

    2010-05-01

    The Melet is one of Turkey's economically important rivers. Most of the petroleum plants are located at fairly nearby of the river This situation is considered as main source of heavy metal pollution in the river. The present study was designed to evaluate the protective role of Ginkgo biloba (GB) on cytotoxicity induced by petroleum wastewater in Vicia faba root tip cells. For this aim, we used the germination percentage, root length, weight gain and micronucleus (MN) frequency as indicators of cytotoxicity. Additionally to the cytological analysis, lipid peroxidation analyses were also performed in V. faba roots. Heavy metal concentrations in wastewater were measured by atomic absorption spectrophotometer (AAS). The V. faba seeds were divided into six groups. They were treated with petroleum wastewater and 10, 20 and 30 microM doses of GB. As a result, the mean concentrations of heavy metals in wastewater were observed in the order: Pb > A > Ni > Cr > Fe > Cu > Zn > Cd. The highest germination percentage was observed in the seeds of the control and positive control groups (in proportion as 98 and 96%, respectively). Wastewater treatment caused a significant decrease in the germination percentage of Group III (in proportion as 44%). The highest root length and weight gain were observed in the seeds of the control and positive control groups at the end of the experimental period. The least root length and weight gain were observed in the seeds of Group III treated with wastewater alone. In the control group, the final weights of all the seeds increased about 4.08 g according to initial weight. The root lengths of the control seeds were measured as 6.80 cm at the end of the experimental period. The final weights of the seeds exposed to wastewater alone increased about 0.90 g according to initial weight. Besides, there was a significantly increase in the MDA levels of the roots exposed to wastewater. Heavy metals in wastewater significantly affected the MDA production indicating lipid peroxidation. But, GB-treatment caused amelioration in indices of the germination percentage, root length, weight gain, MN frequency and lipid peroxidation when compared with group III. Each dose of GB provided protection against wastewater toxicity and its strongest protective effect observed at dose of 30 microM. In vivo results showed that GB is a potential protector against toxicity induced by petroleum wastewater and its protective role is dose-dependent.

  6. Microsatellite markers for the Cabreúva tree, Myroxylon peruiferum (Fabaceae), an endangered medicinal species from the Brazilian Atlantic Forest.

    PubMed

    Schwarcz, K D; Bajay, M M; Macrini, C M T; Salazar, V L P; Souza, A P; Pinheiro, J B; Brancalion, P H S; Rodrigues, R R; Zucchi, M I

    2014-01-01

    The Cabreúva tree, Myroxylon peruiferum, is an endangered tropical species from Brazil used in forest restoration projects. It is known for its medicinal properties. Eleven microsatellite markers were developed for this species, from a microsatellite-enriched library. Nine of these markers, characterized in 30 individuals from a semideciduous forest remnant population in southeast Brazil, were polymorphic, with allele numbers ranging from 2 to 8 per locus; expected and observed heterozygosities ranged from 0.103 to 0.757 and 0.107 to 0.704, respectively. One locus (Mpe-C04) showed significant deviation from Hardy-Weinberg equilibrium, probably due to null alleles. Two other loci (Mpe-E09 and Mpe-H07) were monomorphic in this population. These microsatellite loci should be useful for future population genetic studies of this species. PMID:24737514

  7. Acaricidal activity of leaf extracts of Dalbergia sissoo Roxb. (Fabaceae) against synthetic pyrethroid resistant Rhipicephalus (Boophilus) microplus.

    PubMed

    Singh, Nirbhay Kumar; Jyoti; Vemu, Bhaskar; Prerna, Mranalini; Singh, Harkirat; Dumka, V K; Sharma, S K

    2016-06-01

    Resistance status of Rhipicephalus (Boophilus) microplus against synthetic pyrethroids was assessed by larval packet test which revealed level I and II resistance against cypermethrin and deltamethrin, respectively. Adult immersion test was employed to study the acaricidal activity of leaf extracts of Dalbergia sissoo (sheesham) against these ticks. Mortality and fecundity of ticks exposed to sheesham leaf aqueous (SLA) and ethanolic (SLE) extracts were evaluated at concentrations of 0.625, 1.25, 2.5, 5.0 and 10.0% and controls (distilled water and 10% ethanol). Higher acaricidal activity was recorded in SLA with a lower LC50 (95% CL) value of 1.58% (0.92-2.71%) than SLE [5.25% (4.91-5.63%)]. A significant decrease in egg mass weight and reproductive index was recorded in treated ticks along with an increase in percent inhibition of oviposition. A complete inhibition of hatching was recorded in eggs laid by ticks treated with higher concentrations of SLA, whereas, SLE exhibited no effect on hatching percentage. PMID:27234528

  8. Biological activities of some Acacia spp. (Fabaceae) against new clinical isolates identified by ribosomal RNA gene-based phylogenetic analysis.

    PubMed

    Mahmoud, Mahmoud Fawzy; Alrumman, Sulaiman Abdullah; Hesham, Abd El-Latif

    2016-01-01

    Nowadays,most of the pathogenic bacteria become resistant to antibiotics. Therefore,the pharmaceutical properties of the natural plant extracts have become of interest to researchers as alternative antimicrobial agents. In this study,antibacterial activities of extract gained from Acacia etbaica, Acacia laeta, Acacia origena and Acacia pycnantha have been evaluated against isolated pathogenic bacteria (Strains MFM-01, MFM-10 and AH-09) using agar well diffusion methods.The bacterial strains were isolated from infected individuals,and their exact identification was detected on the basis of 16S rRNA gene amplification and sequence determination. Alignment results and the comparison of 16 SrRN A gene sequences of the isolates to 16 SrRN A gene sequences available in Gen Bank data base as well as the phylogenetic analysis confirmed the accurate position of the isolates as Klebsiella oxytoca strain MFM-01, Staphylococcus aureus strain MFM-10 and Klebsiella pneumoniae strain AH-09. Except for cold water, all tested solvents (Chloroform, petroleum ether, methanol, diethyl ether, and acetone) showed variation in their activity against studied bacteria. GC-MS analysis of ethanol extracts showed that four investigated Acacia species have different phyto components. Eight important pharmaceutical components were found in the legume of Acacia etbaica, seven in the legume of Acacia laeta, fifteen in the legume of Acacia origena and nine in the leaves of Acacia pycnantha. A dendrogram was constructed based on chemical composition, revealed that Acacia laeta is more closely related to Acacia etbaica forming on eclade, whereas Acacia origena less similar to other species. Our results demonstrated that, investigated plants and chemical compounds present could be used as promising antibacterial agents.

  9. Morphological evolution in the variable resin-producing Detarieae (Fabaceae): do morphological characters retain a phylogenetic signal?

    PubMed Central

    Fougère-Danezan, Marie; Herendeen, Patrick S.; Maumont, Stéphan; Bruneau, Anne

    2010-01-01

    Background and Aims Previous molecular phylogenetic studies disagree with the informal generic-level taxonomic groups based on morphology. In this study morphological characters in the caesalpinioid clade Detarieae are evaluated within a phylogenetic framework as a means of better understanding phylogenetic relationships and morphological evolution. Methods Morphological characters were observed and scored for representative species of Detarieae focusing on the resin-producing genera. Phylogenetic analyses were carried out with morphological characters alone and then combined with DNA sequences. Key Results Despite a high level of homoplasy, morphological data support several clades corresponding to those recovered in molecular phylogenetic analyses. The more strongly supported clades are each defined by at least one morphological synapomorphy. Several characters (e.g. apetaly) previously used to define informal generic groups evolved several times independently, leading to the differences observed with the molecular phylogenetic analyses. Although floral evolution is complex in Detarieae some patterns are recovered. Conclusions New informal taxonomic groupings are proposed based on the present findings. Floral evolution in the diverse Detarieae clade is characterized by a repeated tendency toward zygomorphy through the reduction of lateral petals and toward complete loss of petals. PMID:19939978

  10. Larvicidal & ovicidal efficacy of Pithecellobium dulce (Roxb.) Benth. (Fabaceae) against Anopheles stephensi Liston & Aedes aegypti Linn. (Diptera: Culicidae)

    PubMed Central

    Govindarajan, M.; Rajeswary, M.; Sivakumar, R.

    2013-01-01

    Background & objectives: In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, this study was undertaken to assess the larvicidal and ovicidal potential of the crude hexane, benzene, chloroform, ethyl acetate and methanol solvent extracts from the medicinal plant Pithecellobium dulce against the mosquito vectors, Anopheles stephensi and Aedes aegypti (Diptera: Culicidae). Methods: Larvicidal activity of P. dulce plant extracts was studied in the range of 60 to 450 mg/l against early third instar larvae of An. stephensi and Ae. aegypti in the laboratory. The larval mortality was observed after 24 h of exposure. The ovicidal activity was determined against An. stephensi and Ae. aegypti to various concentrations ranging from 100 to 750 mg/l under the laboratory conditions. Mean per cent hatchability of the eggs were observed after 48 h post treatment. Results: All leaf and seed extracts showed moderate larvicidal and ovicidal effects; however, the highest larval mortality was found in methanol extract of leaf of P. dulce against the larvae of An. stephensi and Ae. aegypti with the LC50 and LC90 values 145.43, 155.78 mg/l and 251.23, 279.73 mg/l, respectively. The per cent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. Zero hatchability was observed at 400 mg/l for leaf methanol extract and 625 mg/l for seed methanol extract of P. dulce against An. stephensi and Ae. aegypti, respectively. Compared to leaf extracts, seed extracts have low potency against the two mosquitoes. Interpretation & conclusions: The present results suggest that the leaf and seed extracts of P. dulce have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes. PMID:24056567

  11. Edge effects enhance selfing and seed harvesting efforts in the insect-pollinated Neotropical tree Copaifera langsdorffii (Fabaceae)

    PubMed Central

    Tarazi, R; Sebbenn, A M; Kageyama, P Y; Vencovsky, R

    2013-01-01

    Edge effects may affect the mating system of tropical tree species and reduce the genetic diversity and variance effective size of collected seeds at the boundaries of forest fragments because of a reduction in the density of reproductive trees, neighbour size and changes in the behaviour of pollinators. Here, edge effects on the genetic diversity, mating system and pollen pool of the insect-pollinated Neotropical tree Copaifera langsdorffii were investigated using eight microsatellite loci. Open-pollinated seeds were collected from 17 seed trees within continuous savannah woodland (SW) and were compared with seeds from 11 seed trees at the edge of the savannah remnant. Seeds collected from the SW had significantly higher heterozygosity levels (Ho=0.780; He=0.831) than seeds from the edge (Ho=0.702; He=0.800). The multilocus outcrossing rate was significantly higher in the SW (tm=0.859) than in the edge (tm=0.759). Pollen pool differentiation was significant, however, it did not differ between the SW (=0.105) and the edge (=0.135). The variance effective size within the progenies was significantly higher in the SW (Ne=2.65) than at the edge (Ne=2.30). The number of seed trees to retain the reference variance effective size of 500 was 189 at the SW and 217 at the edge. Therefore, it is preferable that seed harvesting for conservation and environmental restoration strategies be conducted in the SW, where genetic diversity and variance effective size within progenies are higher. PMID:23486081

  12. Antioxidant and orofacial anti-nociceptive activities of the stem bark aqueous extract of Anadenanthera colubrina (Velloso) Brenan (Fabaceae).

    PubMed

    Damascena, N P; Souza, M T S; Almeida, A F; Cunha, R S; Damascena, N P; Curvello, R L; Lima, A C B; Almeida, E C V; Santos, C C S; Dias, A S; Paixão, M S; Souza, L M A; Quintans Júnior, L J; Estevam, C S; Araujo, B S

    2014-01-01

    The anti-nociceptive and antioxidant activities of the Anadenantheracolubrina stem bark aqueous extract (AEAC) were investigated. AEAC (30 μg/mL) reduced 94.8% of 2,2-diphenyl-1-picrylhydrazyl radical and prevented 64% (200 μg/mL) of lipid peroxidation caused by 2,2'-azobis(2-methylpropionamidine) dihydrochloride-induced peroxyl radicals. AEAC treatment (200 and 400 mg/kg) significantly (p < 0.001) reduced mice orofacial nociception in the first (61.4% and 62.6%, respectively) and second (48.9% and 61.9%, respectively) phases of the formalin test. Nociception caused by glutamate was significantly (p < 0.001) reduced by up to 79% at 400 mg/kg, while 56-60% of the nociceptive behaviour induced by capsaicin was significantly inhibited by AEAC (100-400 mg/kg). Mice treated with AEAC did not show changes in motor performance in the Rota-rod apparatus. It appears that AEAC is of pharmacological importance in treating pain due to its anti-nociceptive effects, which were shown to be mediated by central and peripheral mechanisms.

  13. Psoraleaditurnerae and P.vanberkelae (Psoraleeae, Fabaceae): two new species restricted to the Core Cape Region of South Africa.

    PubMed

    Bello, Abubakar; Stirton, Charles H; Chimphango, Samson B M; Muasya, A Muthama

    2015-01-01

    Two new species of Psoralea L. are described: Psoraleaditurnerae A. Bello, C.H. Stirt. & Muasya, sp. nov. and Psoraleavanberkelae C.H. Stirt., A. Bello & Muasya, sp. nov. Psoraleaditurnerae is endemic to the Outeniqua mountains (Camferskloof) and is characterised by a mass of numerous basal shoots out of which emerge 2-3 woody stems up to 2 m tall, 3-foliolate needle-like leaflets at the base of the seasonally growing shoot reducing to one towards the apex and bearing numerous 1-3-flowered axillary inflorescences along its length; each mauve to purple and white flower subtended by a trifid cupulum. Psoraleavanberkelae is characterised by its spreading mounding habit, short tightly packed fleshy leaves, with large impressed papillae, densely glandular short broadly triangular stipules, pale to intense mauve to deep blue flowers, standard with a dark purple central blotch above a M-shaped white patch situated above claw, and khaki seeds with purple flecks.

  14. Exploitation of Erythrina dominguezii Hassl. (Fabaceae) nectar by perching birds in a dry forest in western Brazil.

    PubMed

    Ragusa-Netto, J

    2002-11-01

    Among the vertebrate pollinated plants, the genus Erythrina includes tree species in which birds are the pollen vectors. Two groups in this genus may be distinguished: a) the hummingbird, and b) the perching bird pollinated species. Erythrina dominguezii is included in the second group and occurs in deciduous/semi-deciduous forests in the southwestern neotropics. I studied the exploitation of Erythrina dominguezii nectar by perching birds in a dry forest in western Brazil. Six perching bird species from two distinct groups (Psittacidae: Brotogeris chiriri, Nandayus nenday, Aratinga acuticaudata; Icterinae: Psarocolius decumanus, Icterus cayanensis, I. icterus) consumed its nectar. The two most important consumers were Brotogeris chiriri (51.5% of the flowers visited by birds) and Psarocolius decumanus (20%). While B. chiriri was a flower predator, P. decumanus removed the nectar without damaging the flowers which it opened by inserting its large bill between the standard and the keel. Nandayus nenday, Aratinga acuticaudata, and I. icterus exploited the nectar like P. decumanus, and presumably also contributed to pollen transfer. As the flowering in E. dominguezii was intense and synchronous during the dryest period of the year, and its nectar was highly consumed by birds, the present data suggest that the nectar of this species may be important as an alternative resource to frugivorous/omnivorous birds when other resources are scarce.

  15. The invasive species Ulex europaeus (Fabaceae) shows high dynamism in a fragmented landscape of south-central Chile.

    PubMed

    Altamirano, Adison; Cely, Jenny Paola; Etter, Andrés; Miranda, Alejandro; Fuentes-Ramirez, Andres; Acevedo, Patricio; Salas, Christian; Vargas, Rodrigo

    2016-08-01

    Ulex europaeus (gorse) is an invasive shrub deemed as one of the most invasive species in the world. U. europaeus is widely distributed in the south-central area of Chile, which is considered a world hotspot for biodiversity conservation. In addition to its negative effects on the biodiversity of natural ecosystems, U. europaeus is one of the most severe pests for agriculture and forestry. Despite its importance as an invasive species, U. europaeus has been little studied. Although information exists on the potential distribution of the species, the interaction of the invasion process with the spatial dynamic of the landscape and the landscape-scale factors that control the presence or absence of the species is still lacking. We studied the spatial and temporal dynamics of the landscape and how these relate to U. europaeus invasion in south-central Chile. We used supervised classification of satellite images to determine the spatial distribution of the species and other land covers for the years 1986 and 2003, analysing the transitions between the different land covers. We used logistic regression for modelling the increase, decrease and permanence of U. europaeus invasion considering landscape variables. Results showed that the species covers only around 1 % of the study area and showed a 42 % reduction in area for the studied period. However, U. europaeus was the cover type which presented the greatest dynamism in the landscape. We found a strong relationship between changes in land cover and the invasion process, especially connected with forest plantations of exotic species, which promotes the displacement of U. europaeus. The model of gorse cover increase presented the best performance, and the most important predictors were distance to seed source and landscape complexity index. Our model predicted high spread potential of U. europaeus in areas of high conservation value. We conclude that proper management for this invasive species must take into account the spatial dynamics of the landscape within the invaded area in order to address containment, control or mitigation of the invasion.

  16. Biological activities of some Acacia spp. (Fabaceae) against new clinical isolates identified by ribosomal RNA gene-based phylogenetic analysis.

    PubMed

    Mahmoud, Mahmoud Fawzy; Alrumman, Sulaiman Abdullah; Hesham, Abd El-Latif

    2016-01-01

    Nowadays,most of the pathogenic bacteria become resistant to antibiotics. Therefore,the pharmaceutical properties of the natural plant extracts have become of interest to researchers as alternative antimicrobial agents. In this study,antibacterial activities of extract gained from Acacia etbaica, Acacia laeta, Acacia origena and Acacia pycnantha have been evaluated against isolated pathogenic bacteria (Strains MFM-01, MFM-10 and AH-09) using agar well diffusion methods.The bacterial strains were isolated from infected individuals,and their exact identification was detected on the basis of 16S rRNA gene amplification and sequence determination. Alignment results and the comparison of 16 SrRN A gene sequences of the isolates to 16 SrRN A gene sequences available in Gen Bank data base as well as the phylogenetic analysis confirmed the accurate position of the isolates as Klebsiella oxytoca strain MFM-01, Staphylococcus aureus strain MFM-10 and Klebsiella pneumoniae strain AH-09. Except for cold water, all tested solvents (Chloroform, petroleum ether, methanol, diethyl ether, and acetone) showed variation in their activity against studied bacteria. GC-MS analysis of ethanol extracts showed that four investigated Acacia species have different phyto components. Eight important pharmaceutical components were found in the legume of Acacia etbaica, seven in the legume of Acacia laeta, fifteen in the legume of Acacia origena and nine in the leaves of Acacia pycnantha. A dendrogram was constructed based on chemical composition, revealed that Acacia laeta is more closely related to Acacia etbaica forming on eclade, whereas Acacia origena less similar to other species. Our results demonstrated that, investigated plants and chemical compounds present could be used as promising antibacterial agents. PMID:26826814

  17. Dedicated Deployable Aerobraking Structure

    NASA Technical Reports Server (NTRS)

    Giersch, Louis R.; Knarr, Kevin

    2010-01-01

    A dedicated deployable aerobraking structure concept was developed that significantly increases the effective area of a spacecraft during aerobraking by up to a factor of 5 or more (depending on spacecraft size) without substantially increasing total spacecraft mass. Increasing the effective aerobraking area of a spacecraft (without significantly increasing spacecraft mass) results in a corresponding reduction in the time required for aerobraking. For example, if the effective area of a spacecraft is doubled, the time required for aerobraking is roughly reduced to half the previous value. The dedicated deployable aerobraking structure thus enables significantly shorter aerobraking phases, which results in reduced mission cost, risk, and allows science operations to begin earlier in the mission.

  18. Cosmological structure formation

    NASA Technical Reports Server (NTRS)

    Schramm, David N.

    1991-01-01

    A summary of the current forefront problem of physical cosmology, the formation of structures (galaxies, clusters, great walls, etc.) in the universe is presented. Solutions require two key ingredients: (1) matter; and (2) seeds. Regarding the matter, it now seems clear that both baryonic and non-baryonic matter are required. Whether the non-baryonic matter is hot or cold depends on the choice of seeds. Regarding the seeds, both density fluctuations and topological defects are discussed. The combination of isotropy of the microwave background and the recent observations indicating more power on large scales have severly constrained, if not eliminated, Gaussian fluctuations with equal power on all scales, regardless of the eventual resolution of both the matter and seed questions. It is important to note that all current structure formation ideas require new physics beyond SU(3) x SU(2) x U(1).

  19. Air cathode structure manufacture

    DOEpatents

    Momyer, William R.; Littauer, Ernest L.

    1985-01-01

    An improved air cathode structure for use in primary batteries and the like. The cathode structure includes a matrix active layer, a current collector grid on one face of the matrix active layer, and a porous, nonelectrically conductive separator on the opposite face of the matrix active layer, the collector grid and separator being permanently bonded to the matrix active layer. The separator has a preselected porosity providing low IR losses and high resistance to air flow through the matrix active layer to maintain high bubble pressure during operation of the battery. In the illustrated embodiment, the separator was formed of porous polypropylene. A thin hydrophobic film is provided, in the preferred embodiment, on the current collecting metal grid.

  20. Structure Size Enhanced Histogram

    NASA Astrophysics Data System (ADS)

    Wesarg, Stefan; Kirschner, Matthias

    Direct volume visualization requires the definition of transfer functions (TFs) for the assignment of opacity and color. Multi-dimensional TFs are based on at least two image properties, and are specified by means of 2D histograms. In this work we propose a new type of a 2D histogram which combines gray value with information about the size of the structures. This structure size enhanced (SSE) histogram is an intuitive approach for representing anatomical features. Clinicians — the users we are focusing on — are much more familiar with selecting features by their size than by their gradient magnitude value. As a proof of concept, we employ the SSE histogram for the definition of two-dimensional TFs for the visualization of 3D MRI and CT image data.