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Sample records for affecting leaf bronzing

  1. Photosynthesis affects following night leaf conductance in Vicia faba.

    PubMed

    Easlon, Hsien Ming; Richards, James H

    2009-01-01

    Night-time stomatal opening in C(3) plants may result in significant water loss when no carbon gain is possible. The objective of this study was to determine if endogenous patterns of night-time stomatal opening, as reflected in leaf conductance, in Vicia faba are affected by photosynthetic conditions the previous day. Reducing photosynthesis with low light or low CO(2) resulted in reduced night-time stomatal opening the following night, irrespective of the effects on daytime stomatal conductance. Likewise, increasing photosynthesis with enriched CO(2) levels resulted in increased night-time stomatal opening the following night. Reduced night-time stomatal opening was not the result of an inability to regulate stomatal aperture as leaves with reduced night-time stomatal opening were capable of greater night-time opening when exposed to low CO(2). After acclimating plants to long or short days, it was found that night-time leaf conductance was greater in plants acclimated to short days, and associated with greater leaf starch and nitrate accumulation, both of which may affect night-time guard cell osmotic potential. Direct measurement of guard cell contents during endogenous night-time stomatal opening will help identify the mechanism of the effect of daytime photosynthesis on subsequent night-time stomatal regulation. PMID:19076531

  2. Black leaf streak disease affects starch metabolism in banana fruit.

    PubMed

    Saraiva, Lorenzo de Amorim; Castelan, Florence Polegato; Shitakubo, Renata; Hassimotto, Neuza Mariko Aymoto; Purgatto, Eduardo; Chillet, Marc; Cordenunsi, Beatriz Rosana

    2013-06-12

    Black leaf streak disease (BLSD), also known as black sigatoka, represents the main foliar disease in Brazilian banana plantations. In addition to photosynthetic leaf area losses and yield losses, this disease causes an alteration in the pre- and postharvest behavior of the fruit. The aim of this work was to investigate the starch metabolism of fruits during fruit ripening from plants infected with BLSD by evaluating carbohydrate content (i.e., starch, soluble sugars, oligosaccharides, amylose), phenolic compound content, phytohormones, enzymatic activities (i.e., starch phosphorylases, α- and β-amylase), and starch granules. The results indicated that the starch metabolism in banana fruit ripening is affected by BLSD infection. Fruit from infested plots contained unusual amounts of soluble sugars in the green stage and smaller starch granules and showed a different pattern of superficial degradation. Enzymatic activities linked to starch degradation were also altered by the disease. Moreover, the levels of indole-acetic acid and phenolic compounds indicated an advanced fruit physiological age for fruits from infested plots. PMID:23692371

  3. Bronze diabetes.

    PubMed

    L N, Akshatha; Shenoy, Mamatha T; Yadav, Charu; M S, Rukmini; Kamath, Nutan

    2015-04-01

    Thalassemia is a group of disorders characterized by deficient production of the β-globin sub unit of hemoglobin. The mandatory blood transfusions in patients with thalassemia to maintain adequate erythrocyte levels, leads to iron overload. The prevalence of diabetes in patients with thalassemia varies from 6 to 14%. We here by present a known case of thalassemia major in an 18 year old boy. He was diagnosed with thalassemia before the age of one year and is on regular blood transfusion every two weeks since then. The repeated blood transfusion is one of the common causes for haemochromatosis. Iron overload initially leads to glucose abnormalities such as insulin resistance and hyperinsulinemia, which is followed by impaired secretion of insulin. Diagnosed as a case of bronze diabetes, this patient is on insulin therapy for the last two years. Currently the patient is on iron chelation therapy at Kasturba Medical College Hospital, Mangalore, Karnataka, India. PMID:26023548

  4. Does leaf manipulation affect leaf appearance in italian ryegrass (Lolium multiflorum Lam.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mechanical stimuli such as rubbing, shaking, or flexing plants can alter their growth rates and morphologies. Plant response to mechanical stress can result in delayed plant growth, reduced leaf size, shorten and thicken stems, and reduced yields. Repeated measurements, such as leaf counting or me...

  5. Frequent Occurrence of Tomato Leaf Curl New Delhi Virus in Cotton Leaf Curl Disease Affected Cotton in Pakistan

    PubMed Central

    Zaidi, Syed Shan-e-Ali; Shafiq, Muhammad; Amin, Imran; Scheffler, Brian E.; Scheffler, Jodi A.; Briddon, Rob W.; Mansoor, Shahid

    2016-01-01

    Cotton leaf curl disease (CLCuD) is the major biotic constraint to cotton production on the Indian subcontinent, and is caused by monopartite begomoviruses accompanied by a specific DNA satellite, Cotton leaf curl Multan betasatellite (CLCuMB). Since the breakdown of resistance against CLCuD in 2001/2002, only one virus, the “Burewala” strain of Cotton leaf curl Kokhran virus (CLCuKoV-Bur), and a recombinant form of CLCuMB have consistently been identified in cotton across the major cotton growing areas of Pakistan. Unusually a bipartite isolate of the begomovirus Tomato leaf curl virus was identified in CLCuD-affected cotton recently. In the study described here we isolated the bipartite begomovirus Tomato leaf curl New Delhi virus (ToLCNDV) from CLCuD-affected cotton. To assess the frequency and geographic occurrence of ToLCNDV in cotton, CLCuD-symptomatic cotton plants were collected from across the Punjab and Sindh provinces between 2013 and 2015. Analysis of the plants by diagnostic PCR showed the presence of CLCuKoV-Bur in all 31 plants examined and ToLCNDV in 20 of the samples. Additionally, a quantitative real-time PCR analysis of the levels of the two viruses in co-infected plants suggests that coinfection of ToLCNDV with the CLCuKoV-Bur/CLCuMB complex leads to an increase in the levels of CLCuMB, which encodes the major pathogenicity (symptom) determinant of the complex. The significance of these results are discussed. PMID:27213535

  6. Frequent Occurrence of Tomato Leaf Curl New Delhi Virus in Cotton Leaf Curl Disease Affected Cotton in Pakistan.

    PubMed

    Zaidi, Syed Shan-E-Ali; Shafiq, Muhammad; Amin, Imran; Scheffler, Brian E; Scheffler, Jodi A; Briddon, Rob W; Mansoor, Shahid

    2016-01-01

    Cotton leaf curl disease (CLCuD) is the major biotic constraint to cotton production on the Indian subcontinent, and is caused by monopartite begomoviruses accompanied by a specific DNA satellite, Cotton leaf curl Multan betasatellite (CLCuMB). Since the breakdown of resistance against CLCuD in 2001/2002, only one virus, the "Burewala" strain of Cotton leaf curl Kokhran virus (CLCuKoV-Bur), and a recombinant form of CLCuMB have consistently been identified in cotton across the major cotton growing areas of Pakistan. Unusually a bipartite isolate of the begomovirus Tomato leaf curl virus was identified in CLCuD-affected cotton recently. In the study described here we isolated the bipartite begomovirus Tomato leaf curl New Delhi virus (ToLCNDV) from CLCuD-affected cotton. To assess the frequency and geographic occurrence of ToLCNDV in cotton, CLCuD-symptomatic cotton plants were collected from across the Punjab and Sindh provinces between 2013 and 2015. Analysis of the plants by diagnostic PCR showed the presence of CLCuKoV-Bur in all 31 plants examined and ToLCNDV in 20 of the samples. Additionally, a quantitative real-time PCR analysis of the levels of the two viruses in co-infected plants suggests that coinfection of ToLCNDV with the CLCuKoV-Bur/CLCuMB complex leads to an increase in the levels of CLCuMB, which encodes the major pathogenicity (symptom) determinant of the complex. The significance of these results are discussed. PMID:27213535

  7. Benzothiadiazole affects the leaf proteome in arctic bramble (Rubus arcticus).

    PubMed

    Hukkanen, Anne; Kokko, Harri; Buchala, Antony; Häyrinen, Jukka; Kärenlampi, Sirpa

    2008-11-01

    Benzothiadiazole (BTH) induces resistance to the downy mildew pathogen, Peronospora sparsa, in arctic bramble, but the basis for the BTH-induced resistance is unknown. Arctic bramble cv. Mespi was treated with BTH to study the changes in leaf proteome and to identify proteins with a putative role in disease resistance. First, BTH induced strong expression of one PR-1 protein isoform, which was also induced by salicylic acid (SA). The PR-1 was responsive to BTH and exogenous SA despite a high endogenous SA content (20-25 microg/g fresh weight), which increased to an even higher level after treatment with BTH. Secondly, a total of 792 protein spots were detected in two-dimensional gel electrophoresis, eight proteins being detected solely in the BTH-treated plants. BTH caused up- or down-regulation of 72 and 31 proteins, respectively, of which 18 were tentatively identified by mass spectrometry. The up-regulation of flavanone-3-hydroxylase, alanine aminotransferase, 1-aminocyclopropane-1-carboxylate oxidase, PR-1 and PR-10 proteins may partly explain the BTH-induced resistance against P. sparsa. Other proteins with changes in intensity appear to be involved in, for example, energy metabolism and protein processing. The decline in ATP synthase, triosephosphate isomerase, fructose bisphosphate aldolase and glutamine synthetase suggests that BTH causes significant changes in primary metabolism, which provides one possible explanation for the decreased vegetative growth of foliage and rhizome observed in BTH-treated plants. PMID:19019008

  8. Developmental changes in carbon and nitrogen metabolism affect tea quality in different leaf position.

    PubMed

    Li, Zhi-Xin; Yang, Wei-Jun; Ahammed, Golam Jalal; Shen, Chen; Yan, Peng; Li, Xin; Han, Wen-Yan

    2016-09-01

    Leaf position represents a specific developmental stage that influences both photosynthesis and respiration. However, the precise relationships between photosynthesis and respiration in different leaf position that affect tea quality are largely unknown. Here, we show that the effective quantum yield of photosystem II [ΦPSⅡ] as well as total chlorophyll concentration (TChl) of tea leaves increased gradually with leaf maturity. Moreover, respiration rate (RR) together with total nitrogen concentration (TN) decreased persistently, but total carbon remained unchanged during leaf maturation. Analyses of major N-based organic compounds revealed that decrease in TN was attributed to a significant decrease in the concentration of caffeine and amino acids (AA) in mature leaves. Furthermore, soluble sugar (SS) decreased, but starch concentration increased with leaf maturity, indicating that source-sink relationship was altered during tea leaf development. Detailed correlation analysis showed that ΦPSⅡ was negatively correlated with RR, SS, starch, tea polyphenol (TP), total catechins and TN, but positively correlated with TChl; while RR was positively correlated with TN, SS, TP and caffeine, but negatively correlated with TChl and starch concentrations. Our results suggest that biosynthesis of chlorophyll, catechins and polyphenols is closely associated with photosynthesis and respiration in different leaf position that greatly influences the relationship between primary and secondary metabolism in tea plants. PMID:27380366

  9. Leaf optical properties are affected by the location and type of deposited biominerals.

    PubMed

    Klančnik, Katja; Vogel-Mikuš, Katarina; Kelemen, Mitja; Vavpetič, Primož; Pelicon, Primož; Kump, Peter; Jezeršek, David; Gianoncelli, Alessandra; Gaberščik, Alenka

    2014-11-01

    This study aimed to relate the properties of incrusted plant tissues and structures as well as biomineral concentrations and localization with leaf reflectance and transmittance spectra from 280nm to 880nm in the grasses Phragmites australis, Phalaris arundinacea, Molinia caerulea and Deschampsia cespitosa, and the sedge Carex elata. Redundancy analysis revealed that prickle-hair length on adaxial surface and thickness of lower epidermis exerted significant effects in P. australis; prickle-hair density at abaxial leaf surface and thickness of epidermis on adaxial leaf surface in P. arundinacea; thickness of epidermis on adaxial leaf in D. cespitosa; prickle-hair density on adaxial leaf surface and thickness of cuticle in M. caerulea; and prickle-hair density on adaxial leaf surface and cuticle thickness of the lower side in C. elata. Micro-PIXE and LEXRF elemental localization analysis show that all of these structures and tissues are encrusted by Si and/or by Ca. Reflectance spectra were significantly affected by the Ca concentrations, while Si and Mg concentrations and the Ca concentrations significantly affected transmittance spectra. High concentrations of Mg were detected in epidermal vacuoles of P. arundinacea, M. caerulea and D. cespitosa. Al co-localises with Si in the cuticle, epidermis and/or prickle hairs. PMID:25194526

  10. Auxin and LANCEOLATE affect leaf shape in tomato via different developmental processes.

    PubMed

    Ben-Gera, Hadas; Ori, Naomi

    2012-10-01

    Elaboration of a complex leaves depends on the morphogenetic activity of a specific tissue at the leaf margin termed marginal-blastozon (MB). In tomato (Solanum lycopersicym), prolonged activity of the MB leads to the development of compound leaves. The activity of the MB is restricted by the TCP transcription factor LANCEOLATE (LA). Plants harboring the dominant LA mutant allele La-2 have simple leaves with a uniform blade. Conversely, leaves of pFIL > > miR319 are compound and grow indeterminately in their margins due to leaf overexpression of miR319, a negative regulator of LA and additional miR319-sensitive genes. We have recently shown that the auxin-response sensor DR5::VENUS marks and precedes leaflet initiation events in the MB. Mutations in ENTIRE (E), an auxin signal inhibitor from the Aux/IAA family, lead to the expansion of the DR5::VENUS signal to throughout the leaf-primordia margin, and to a simplified leaf phenotype. Here, we examined the interaction between auxin, E, and LA in tomato leaf development. In La-2 leaf primordia, the auxin signal is very weak and is diffused to throughout the leaf margin, suggesting that auxin acts within the developmental-context of MB activity, which is controlled by LA. e La-2 double mutants showed an enhanced simple leaf phenotype and e pFIL > > miR319 leaves initiated less leaflets than wild-type, but their margins showed continuous growth. These results suggest that E and auxin affect leaflet initiation within the context of the extended MB activity, but their influence on the extent of indeterminate growth of the leaf is minor. PMID:22902691

  11. Human brains found in a fire-affected 4000-years old Bronze Age tumulus layer rich in soil alkalines and boron in Kutahya, Western Anatolia.

    PubMed

    Altinoz, M A; Ince, B; Sav, A; Dincer, A; Cengiz, S; Mercan, S; Yazici, Z; Bilgen, M N

    2014-02-01

    Undecomposed human bodies and organs always attracted interest in terms of understanding biological tissue stability and immortality. Amongst these, cases of natural mummification found in glaciers, bog sediments and deserts caused even more attention. In 2010, an archeological excavation of a Bronze Age layer in a tumulus near the Western Anatolia city Kütahya revealed fire affected regions with burnt human skeletons and charred wooden objects. Inside of the cracked skulls, undecomposed brains were discernible. To analyze the burial taphonomy of the rare phenomenon of brain preservation, we analyzed brains, bone, teeth and surrounding soils elements using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Adipocere formation or saponification of postmortem tissue fat requires high levels of alkalinity and especially potassium. Indeed, ICP-MS analysis of the brain, teeth and bone and also of the surrounding soil revealed high levels of potassium, magnesium, aluminum and boron, which are compatible with the famous role of Kütahya in tile production with its soil containing high level of alkalines and tile-glazing boron. Fatty acid chromatography revealed simultaneous saturation of fats and protection of fragile unsaturated fatty acids consistent with soil-presence of both pro-oxidant and anti-oxidant trace metals. Computerized tomography revealed protection of diencephalic, metencephalic and occipital tissue in one of the best-preserved specimens. Boron was previously found as an intentional preservative of Tutankhamen and Deir el Bahari mummies. Here, in natural soil with its insect-repellant, anti-bacterial and fire-resistance qualities it may be a factor to preserve heat-affected brains as almost bioporcellain specimens. PMID:24060546

  12. Factors affecting survival of bacteriophage on tomato leaf surfaces.

    PubMed

    Iriarte, F B; Balogh, B; Momol, M T; Smith, L M; Wilson, M; Jones, J B

    2007-03-01

    The ability of bacteriophage to persist in the phyllosphere for extended periods is limited by many factors, including sunlight irradiation, especially in the UV zone, temperature, desiccation, and exposure to copper bactericides. The effects of these factors on persistence of phage and formulated phage (phage mixed with skim milk) were evaluated. In field studies, copper caused significant phage reduction if applied on the day of phage application but not if applied 4 or 7 days in advance. Sunlight UV was evaluated for detrimental effects on phage survival on tomato foliage in the field. Phage was applied in the early morning, midmorning, early afternoon, and late evening, while UVA plus UVB irradiation and phage populations were monitored. The intensity of UV irradiation positively correlated with phage population decline. The protective formulation reduced the UV effect. In order to demonstrate direct effects of UV, phage suspensions were exposed to UV irradiation and assayed for effectiveness against bacterial spot of tomato. UV significantly reduced phage ability to control bacterial spot. Ambient temperature had a pronounced effect on nonformulated phage but not on formulated phages. The effects of desiccation and fluorescent light illumination on phage were investigated. Desiccation caused a significant but only slight reduction in phage populations after 60 days, whereas fluorescent light eliminated phages within 2 weeks. The protective formulation eliminated the reduction caused by both of these factors. Phage persistence was dramatically affected by UV, while the other factors had less pronounced effects. Formulated phage reduced deleterious effects of the studied environmental factors. PMID:17259361

  13. Habitat, food, and climate affecting leaf litter anuran assemblages in an Atlantic Forest remnant

    NASA Astrophysics Data System (ADS)

    Rievers, Camila Rabelo; Pires, Maria Rita Silvério; Eterovick, Paula Cabral

    2014-07-01

    Leaf litter anuran assemblages include both species that have terrestrial development and species that, during the breeding season, aggregate around bodies of water where their tadpoles develop. The resources used by these two groups in the leaf litter are likely to differ, as well as their sampled species richness, abundance and biomass as resource availability changes. We conducted a 12-month survey of leaf litter anuran assemblages at three forest areas in the largest Atlantic Forest remnant in the state of Minas Gerais in southeastern Brazil. Each month we estimated, based on capture rates, anuran species richness, abundance, and biomass as assemblage descriptors. We also measured variables that could potentially affect these descriptors in space and time: invertebrate litter fauna (abundance and richness of taxa), leaf litter biomass, and microclimatic conditions (air humidity, air and soil temperature, soil water content, and rainfall). We tested for differences in these variables among areas. We used general linear models to search for the variables that best explained variation in anuran abundance (based on capture rates) throughout the year. We analyzed species with terrestrial development (TD) and with aquatic larvae (AL) separately. We recorded 326 anurans of 15 species. Sampled anuran abundance (correlated to species richness and biomass) was explained by air humidity and/or invertebrate abundance for species with TD, and by soil water content or air humidity and leaf litter biomass for species with AL. The variability in the results of studies on leaf litter frogs that try to find variables to explain changes in community descriptors may be due to spatial variation of resources among areas and also to the fact that TD and AL species are frequently analyzed together, when in fact they are likely to show different responses to resources present in the leaf litter habitat, reflected on capture rates.

  14. Root cooling strongly affects diel leaf growth dynamics, water and carbohydrate relations in Ricinus communis.

    PubMed

    Poiré, Richard; Schneider, Heike; Thorpe, Michael R; Kuhn, Arnd J; Schurr, Ulrich; Walter, Achim

    2010-03-01

    In laboratory and greenhouse experiments with potted plants, shoots and roots are exposed to temperature regimes throughout a 24 h (diel) cycle that can differ strongly from the regime under which these plants have evolved. In the field, roots are often exposed to lower temperatures than shoots. When the root-zone temperature in Ricinus communis was decreased below a threshold value, leaf growth occurred preferentially at night and was strongly inhibited during the day. Overall, leaf expansion, shoot biomass growth, root elongation and ramification decreased rapidly, carbon fluxes from shoot to root were diminished and carbohydrate contents of both root and shoot increased. Further, transpiration rate was not affected, yet hydrostatic tensions in shoot xylem increased. When root temperature was increased again, xylem tension reduced, leaf growth recovered rapidly, carbon fluxes from shoot to root increased, and carbohydrate pools were depleted. We hypothesize that the decreased uptake of water in cool roots diminishes the growth potential of the entire plant - especially diurnally, when the growing leaf loses water via transpiration. As a consequence, leaf growth and metabolite concentrations can vary enormously, depending on root-zone temperature and its heterogeneity inside pots. PMID:19968824

  15. Tadpoles of Early Breeding Amphibians are Negatively Affected by Leaf Litter From Invasive Chinese Tallow Trees

    NASA Astrophysics Data System (ADS)

    Leonard, N. E.

    2005-05-01

    As wetlands are invaded by Chinese tallow trees (Triadica sebifera), native trees are displaced and detrital inputs to amphibian breeding ponds are altered. I used a mesocosm experiment to examine the effect of Chinese tallow leaf litter on the survival to, size at, and time to metamorphosis of amphibian larvae. Fifty 1000-L cattle watering tanks were treated with 1500 g dry weight of one of five leaf litter treatments: Chinese tallow, laurel oak (Quercus laurifolia), water tupelo (Nyssa aquatica), slash pine (Pinus elliottii), or a 3:1:1:1 mixture. Each tank received 45 tadpoles of Pseudacris feriarum, Bufo terrestris, and Hyla cinerea in sequence according to their natural breeding phonologies. Every Pseudacris feriarum and Bufo terrestris tadpole exposed to Chinese tallow died prior to metamorphosis. Hyla cinerea survival in tanks with tallow-only was significantly lower than that observed for all other leaf treatments. Hyla cinerea tadpoles from tallow-only and mixed-leaf treatments were larger at metamorphosis and transformed faster than those in tanks with native leaves only. These results suggest that Chinese tallow leaf litter may negatively affect tadpoles of early breeding frogs and that Chinese tallow invasion may change the structure of amphibian communities in temporary ponds.

  16. Citrus Leaf Volatiles as Affected by Developmental Stage and Genetic Type

    PubMed Central

    Azam, Muhammad; Jiang, Qian; Zhang, Bo; Xu, Changjie; Chen, Kunsong

    2013-01-01

    Major volatiles from young and mature leaves of different citrus types were analyzed by headspace-solid phase microextraction (HS-SPME)-GC-MS. A total of 123 components were identified form nine citrus cultivars, including nine aldehydes, 19 monoterpene hydrocarbons, 27 oxygenated monoterpenes, 43 sesquiterpene hydrocarbons, eight oxygenated sesquiterpenes, two ketones, six esters and nine miscellaneous. Young leaves produced higher amounts of volatiles than mature leaves in most cultivars. The percentage of aldehyde and monoterpene hydrocarbons increased, whilst oxygenated monoterpenes and sesquiterpenes compounds decreased during leaf development. Linalool was the most abundant compound in young leaves, whereas limonene was the chief component in mature ones. Notably, linalool content decreased, while limonene increased, during leaf development in most cultivars. Leaf volatiles were also affected by genetic types. A most abundant volatile in one or several genotypes can be absent in another one(s), such as limonene in young leaves of lemon vs. Satsuma mandarin and β-terpinene in mature leaves of three genotypes vs. the other four. Compositional data was subjected to multivariate statistical analysis, and variations in leaf volatiles were identified and clustered into six groups. This research determining the relationship between production of major volatiles from different citrus varieties and leaf stages could be of use for industrial and culinary purposes. PMID:23994837

  17. Bronze rainbow hologram mirrors

    NASA Astrophysics Data System (ADS)

    Dawson, P.

    2006-02-01

    This project draws on holographic embossing techniques, ancient artistic conventions of bronze mirror design and modelling and casting processes to accomplish portraiture of reflection. Laser scanning, 3D computer graphics and holographic imaging are employed to enable a permanent 3D static holographic image to appear integrated with the real-time moving reflection of a viewer's face in a polished bronze disc. The disc and the figure which holds it (caryatid) are cast in bronze from a lost wax model, a technique which has been used for millennia to make personal mirrors. The Caryatid form of bronze mirror which went through many permutations in ancient Egyptian, Greece and Rome shows a plethora of expressive figure poses ranging from sleek nudes to highly embellished multifigure arrangements. The prototype of this series was made for Australian choreographer Graeme Murphy, Artistic Director of the Sydney Dance Company. Each subsequent mirror will be unique in figure and holographic imagery as arranged between artist and subject. Conceptually this project references both the modern experience of viewing mirrors retrieved from ancient tombs, which due to deterioration of the surface no longer reflect, and the functioning of Chinese Magic mirrors, which have the ability to project a predetermined image. Inspired by the metaphorical potential of these mirrors, which do not reflect the immediate reality of the viewer, this bronze hologram mirror series enables each viewer to reflect upon himself or herself observing simultaneously the holographic image and their own partially obliterated reflection.

  18. Seasonal Variability May Affect Microbial Decomposers and Leaf Decomposition More Than Warming in Streams.

    PubMed

    Duarte, Sofia; Cássio, Fernanda; Ferreira, Verónica; Canhoto, Cristina; Pascoal, Cláudia

    2016-08-01

    Ongoing climate change is expected to affect the diversity and activity of aquatic microbes, which play a key role in plant litter decomposition in forest streams. We used a before-after control-impact (BACI) design to study the effects of warming on a forest stream reach. The stream reach was divided by a longitudinal barrier, and during 1 year (ambient year) both stream halves were at ambient temperature, while in the second year (warmed year) the temperature in one stream half was increased by ca. 3 °C above ambient temperature (experimental half). Fine-mesh bags containing oak (Quercus robur L.) leaves were immersed in both stream halves for up to 60 days in spring and autumn of the ambient and warmed years. We assessed leaf-associated microbial diversity by denaturing gradient gel electrophoresis and identification of fungal conidial morphotypes and microbial activity by quantifying leaf mass loss and productivity of fungi and bacteria. In the ambient year, no differences were found in leaf decomposition rates and microbial productivities either between seasons or stream halves. In the warmed year, phosphorus concentration in the stream water, leaf decomposition rates, and productivity of bacteria were higher in spring than in autumn. They did not differ between stream halves, except for leaf decomposition, which was higher in the experimental half in spring. Fungal and bacterial communities differed between seasons in both years. Seasonal changes in stream water variables had a greater impact on the activity and diversity of microbial decomposers than a warming regime simulating a predicted global warming scenario. PMID:27193000

  19. Evidence for mild sediment Pb contamination affecting leaf-litter decomposition in a lake.

    PubMed

    Oguma, Andrew Y; Klerks, Paul L

    2015-08-01

    Much work has focused on the effects of metal-contaminated sediment on benthic community structure, but effects on ecosystem functions have received far less attention. Decomposition has been widely used as an integrating metric of ecosystem function in lotic systems, but not for lentic ones. We assessed the relationship between low-level sediment lead (Pb) contamination and leaf-litter decomposition in a lentic system. We measured 30-day weight loss in 30 litter-bags that were deployed along a Pb-contamination gradient in a cypress-forested lake. At each deployment site we also quantified macrobenthos abundance, dissolved oxygen, water depth, sediment organic content, sediment silt/clay content, and both total sediment and porewater concentrations of Cd, Cu, Ni, Pb and Zn. Principal components (PC) analysis revealed a negative relationship between Pb concentration and benthic macroinvertebrate abundance, and this covariation dominated the first PC axis (PC1). Subsequent correlation analyses revealed a negative relationship between PC1 and percent leaf-litter loss. Our results indicate that leaf-litter decomposition was related to sediment Pb and benthic macroinvertebrate abundance. They also showed that ecosystem function may be affected even where sediment Pb concentrations are mostly below threshold-effects sediment quality guidelines--a finding with potential implications for sediment risk assessment. Additionally, the litter-bag technique used in this study showed promise as a tool in risk assessments of metal-contaminated sediments in lentic systems. PMID:26115904

  20. Increasing shrub abundance and N addition in Arctic tundra affect leaf and root litter decomposition differently

    NASA Astrophysics Data System (ADS)

    McLaren, J.; van de Weg, M. J.; Shaver, G. R.; Gough, L.

    2013-12-01

    Changes in global climate have resulted in a ';greening' of the Arctic as the abundance of deciduous shrub species increases. Consequently, not only the living plant community, but also the litter composition changes, which in turn can affect carbon turnover patterns in the Arctic. We examined effects of changing litter composition (both root and leaf litter) on decomposition rates with a litter bag study, and specifically focused on the impact of deciduous shrub Betula nana litter on litter decomposition from two evergreen shrubs (Ledum palustre, and Vaccinium vitis-idaea) and one graminoid (Eriophorum vaginatum) species. Additionally, we investigated how decomposition was affected by nutrient availability by placing the litterbags in an ambient and a fertilized moist acidic tundra environment. Measurements were carried out seasonally over 2 years (after snow melt, mid-growing season, end growing season). We measured litter mass loss over time, as well as the respiration rates (standardized for temperature and moisture) and temperature sensitivity of litter respiration at the time of harvesting the litter bags. For leaves, Betula litter decomposed faster than the other three species, with Eriophorum leaves decomposing the slowest. This pattern was observed for both mass loss and litter respiration rates, although the differences in respiration became smaller over time. Surprisingly, combining Betula with any other species resulted in slower overall weight loss rates than would be predicted based on monoculture weight loss rates. This contrasted with litter respiration at the time of sampling, which showed a positive mixing effect of adding Betula leaf liter to the other species. Apparently, during the first winter months (September - May) Betula litter decomposition is negatively affected by mixing the species and this legacy can still be observed in the total mass loss results later in the year. For root litter there were fewer effects of species identity on root

  1. Frequent Occurrence of Tomato Leaf Curl New Delhi Virus in Cotton Leaf Curl Disease Affected Cotton in Pakistan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton leaf curl disease (CLCuD) in the Indian subcontinent is associated with several distinct monopartite begomoviruses and DNA satellites. However, only a single begomovirus was associated with breakdown of resistance against CLCuD in previously resistant cotton varieties. The monopartite begomov...

  2. Does Initial Leaf Chemistry Affect the Contribution of Insects, Fungi, and Bacteria to Leaf Breakdown in a Lowland Tropical Stream?

    NASA Astrophysics Data System (ADS)

    Ardon, M.; Pringle, C. M.

    2005-05-01

    We examined effects of initial leaf chemistry of six common riparian species on the relative contribution of fungi, bacteria, and invertebrates to leaf breakdown in a lowland stream in Costa Rica. We hypothesized that fungi and bacteria would contribute more to the breakdown of species with low concentrations of secondary (tannins and phenolics) and structural (cellulose and lignin) compounds, while invertebrates would be more important in the processing of species with high concentrations of secondary and structural compounds. We incubated single species leaf bags of six common riparian species, representing a range in secondary and structural compounds, in a third-order stream at La Selva Biological Station, Costa Rica. We measured leaf chemistry during the breakdown process. We determined fungal biomass using ergosterol methods, bacteria using DAPI counts, and invertebrate biomass using length-weight regressions. We then used biomass estimates for each group to determine their contribution to the overall breakdown process. Breakdown rates ranged from very fast (Trema integerima, k = 0.23 day-1) to slow (Zygia longifolia , k = 0.011 day-1). While analyses are still under way, preliminary results support our initial hypothesis that fungi contribute more to the break down of leaves from tree species with low concentrations of secondary and structural compounds.

  3. Diversity and Composition of the Leaf Mycobiome of Beech (Fagus sylvatica) Are Affected by Local Habitat Conditions and Leaf Biochemistry

    PubMed Central

    Unterseher, Martin; Siddique, Abu Bakar; Brachmann, Andreas; Peršoh, Derek

    2016-01-01

    Comparative investigations of plant-associated fungal communities (mycobiomes) in distinct habitats and under distinct climate regimes have been rarely conducted in the past. Nowadays, high-throughput sequencing allows routine examination of mycobiome responses to environmental changes and results at an unprecedented level of detail. In the present study, we analysed Illumina-generated fungal ITS1 sequences from European beech (Fagus sylvatica) originating from natural habitats at two different altitudes in the German Alps and from a managed tree nursery in northern Germany. In general, leaf-inhabiting mycobiome diversity and composition correlated significantly with the origin of the trees. Under natural condition the mycobiome was more diverse at lower than at higher elevation, whereas fungal diversity was lowest in the artificial habitat of the tree nursery. We further identified significant correlation of leaf chlorophylls and flavonoids with both habitat parameters and mycobiome biodiversity. The present results clearly point towards a pronounced importance of local stand conditions for the structure of beech leaf mycobiomes and for a close interrelation of phyllosphere fungi and leaf physiology. PMID:27078859

  4. Diversity and Composition of the Leaf Mycobiome of Beech (Fagus sylvatica) Are Affected by Local Habitat Conditions and Leaf Biochemistry.

    PubMed

    Unterseher, Martin; Siddique, Abu Bakar; Brachmann, Andreas; Peršoh, Derek

    2016-01-01

    Comparative investigations of plant-associated fungal communities (mycobiomes) in distinct habitats and under distinct climate regimes have been rarely conducted in the past. Nowadays, high-throughput sequencing allows routine examination of mycobiome responses to environmental changes and results at an unprecedented level of detail. In the present study, we analysed Illumina-generated fungal ITS1 sequences from European beech (Fagus sylvatica) originating from natural habitats at two different altitudes in the German Alps and from a managed tree nursery in northern Germany. In general, leaf-inhabiting mycobiome diversity and composition correlated significantly with the origin of the trees. Under natural condition the mycobiome was more diverse at lower than at higher elevation, whereas fungal diversity was lowest in the artificial habitat of the tree nursery. We further identified significant correlation of leaf chlorophylls and flavonoids with both habitat parameters and mycobiome biodiversity. The present results clearly point towards a pronounced importance of local stand conditions for the structure of beech leaf mycobiomes and for a close interrelation of phyllosphere fungi and leaf physiology. PMID:27078859

  5. Do variations in leaf phenology affect radial growth variations in Fagus sylvatica?

    NASA Astrophysics Data System (ADS)

    Čufar, Katarina; De Luis, Martin; Prislan, Peter; Gričar, Jožica; Črepinšek, Zalika; Merela, Maks; Kajfež-Bogataj, Lučka

    2015-08-01

    We used a dendrochronological and leaf phenology network of European beech ( Fagus sylvatica) in Slovenia, a transitional area between Mediterranean, Alpine and continental climatic regimes, for the period 1955-2007 to test whether year to year variations in leaf unfolding and canopy duration (i.e. time between leaf unfolding and colouring) influence radial growth (annual xylem production and tree ring widths) and if such influences are more pronounced at higher altitudes. We showed that variability in leaf phenology has no significant effect on variations in radial growth. The results are consistent in the entire region, irrespective of the climatic regime or altitude, although previous studies have shown that leaf phenology and tree ring variation depend on altitude. The lack of relationship between year to year variability in leaf phenology and radial growth may suggest that earlier leaf unfolding—as observed in a previous study—probably does not cause increased tree growth rates in beech in Slovenia.

  6. Prior Hydrologic Disturbance Affects Competition between Aedes Mosquitoes via Changes in Leaf Litter.

    PubMed

    Smith, Cassandra D; Freed, T Zachary; Leisnham, Paul T

    2015-01-01

    Allochthonous leaf litter is often the main resource base for invertebrate communities in ephemeral water-filled containers, and detritus quality can be affected by hydrologic conditions. The invasive mosquito Aedes albopictus utilizes container habitats for its development where it competes as larvae for detritus and associated microorganisms with the native Aedes triseriatus. Different hydrologic conditions that containers are exposed to prior to mosquito utilization affect litter decay and associated water quality. We tested the hypothesis that larval competition between A. albopictus and A. triseriatus would be differentially affected by prior hydrologic conditions. Experimental microcosms provisioned with Quercus alba L. litter were subjected to one of three different hydrologic treatments prior to the addition of water and mosquito larvae: dry, flooded, and a wet/dry cycle. Interspecific competition between A. albopictus and A. triseriatus was mediated by hydrologic treatment, and was strongest in the dry treatment vs. the flooded or wet/dry treatments. Aedes triseriatus estimated rate of population change (λ') was lowest in the dry treatment. Aedes albopictus λ' was unaffected by hydrologic treatment, and was on average always increasing (i.e., > 1). Aedes triseriatus λ' was affected by the interaction of hydrologic treatment with interspecific competition, and was on average declining (i.e., < 1.0), at the highest interspecific densities in the dry treatment. Dry treatment litter had the slowest decay rate and leached the highest concentration of tannin-lignin, but supported more total bacteria than the other treatments. These results suggest that dry conditions negatively impact A. triseriatus population performance and may result in the competitive exclusion of A. triseriatus by A. albopictus, possibly by reducing microbial taxa that Aedes species browse. Changing rainfall patterns with climate change are likely to affect competition between A

  7. Prior Hydrologic Disturbance Affects Competition between Aedes Mosquitoes via Changes in Leaf Litter

    PubMed Central

    Smith, Cassandra D.; Freed, T. Zachary; Leisnham, Paul T.

    2015-01-01

    Allochthonous leaf litter is often the main resource base for invertebrate communities in ephemeral water-filled containers, and detritus quality can be affected by hydrologic conditions. The invasive mosquito Aedes albopictus utilizes container habitats for its development where it competes as larvae for detritus and associated microorganisms with the native Aedes triseriatus. Different hydrologic conditions that containers are exposed to prior to mosquito utilization affect litter decay and associated water quality. We tested the hypothesis that larval competition between A. albopictus and A. triseriatus would be differentially affected by prior hydrologic conditions. Experimental microcosms provisioned with Quercus alba L. litter were subjected to one of three different hydrologic treatments prior to the addition of water and mosquito larvae: dry, flooded, and a wet/dry cycle. Interspecific competition between A. albopictus and A. triseriatus was mediated by hydrologic treatment, and was strongest in the dry treatment vs. the flooded or wet/dry treatments. Aedes triseriatus estimated rate of population change (λ') was lowest in the dry treatment. Aedes albopictus λ' was unaffected by hydrologic treatment, and was on average always increasing (i.e., > 1). Aedes triseriatus λ' was affected by the interaction of hydrologic treatment with interspecific competition, and was on average declining (i.e., < 1.0), at the highest interspecific densities in the dry treatment. Dry treatment litter had the slowest decay rate and leached the highest concentration of tannin-lignin, but supported more total bacteria than the other treatments. These results suggest that dry conditions negatively impact A. triseriatus population performance and may result in the competitive exclusion of A. triseriatus by A. albopictus, possibly by reducing microbial taxa that Aedes species browse. Changing rainfall patterns with climate change are likely to affect competition between A

  8. Epigenetic Mutation of RAV6 Affects Leaf Angle and Seed Size in Rice.

    PubMed

    Zhang, Xiangqian; Sun, Jing; Cao, Xiaofeng; Song, Xianwei

    2015-11-01

    Heritable epigenetic variants of genes, termed epialleles, can broaden genetic and phenotypic diversity in eukaryotes. Epialleles may also provide a new source of beneficial traits for crop breeding, but very few epialleles related to agricultural traits have been identified in crops. Here, we identified Epi-rav6, a gain-of-function epiallele of rice (Oryza sativa) RELATED TO ABSCISIC ACID INSENSITIVE3 (ABI3)/VIVIPAROUS1 (VP1) 6 (RAV6), which encodes a B3 DNA-binding domain-containing protein. The Epi-rav6 plants show larger lamina inclination and smaller grain size; these agronomically important phenotypes are inherited in a semidominant manner. We did not find nucleotide sequence variation of RAV6. Instead, we found hypomethylation in the promoter region of RAV6, which caused ectopic expression of RAV6 in Epi-rav6 plants. Bisulfite analysis revealed that cytosine methylation of four CG and two CNG loci within a continuous 96-bp region plays essential roles in regulating RAV6 expression; this region contains a conserved miniature inverted repeat transposable element transposon insertion in cultivated rice genomes. Overexpression of RAV6 in the wild type phenocopied the Epi-rav6 phenotype. The brassinosteroid (BR) receptor BR INSENSITIVE1 and BR biosynthetic genes EBISU DWARF, DWARF11, and BR-DEFICIENT DWARF1 were ectopically expressed in Epi-rav6 plants. Also, treatment with a BR biosynthesis inhibitor restored the leaf angle defects of Epi-rav6 plants. This indicates that RAV6 affects rice leaf angle by modulating BR homeostasis and demonstrates an essential regulatory role of epigenetic modification on a key gene controlling important agricultural traits. Thus, our work identifies a unique rice epiallele, which may represent a common phenomenon in complex crop genomes. PMID:26351308

  9. Alterations in lignin content and phenylpropanoids pathway in date palm (Phoenix dactylifera L.) tissues affected by brittle leaf disease.

    PubMed

    Saidi, Mohammed Najib; Bouaziz, Donia; Hammami, Ines; Namsi, Ahmed; Drira, Noureddine; Gargouri-Bouzid, Radhia

    2013-10-01

    Brittle leaf disease or Maladie de la Feuille Cassante (MFC) is a lethal disorder of date palm that has assumed epidemic proportions in the oases of Tunisia and Algeria. No pathogen could ever be associated with the disease, while leaflets of affected palms have been previously shown to be deficient in manganese. The work reported here aims to understand the biochemical basis of the date palm response to this disorder. Since the typical disease symptom is the leaf fragility, we have investigated lignin content in leaves and roots. Strong decrease in total lignin content was observed in affected leaves, while lignin content increased in affected roots. Histochemical analyses showed hyperlignification thicker suberin layer in roots cortical cells. The phenylpropanoids pathway was also disrupted in leaves and roots, cinnamoyl-CoA reductase and cinnamyl-alcohol dehydrogenase gene expression was affected by the disease which severely affects the cell wall integrity. PMID:23987806

  10. The ASYMMETRIC LEAVES Complex Employs Multiple Modes of Regulation to Affect Adaxial-Abaxial Patterning and Leaf Complexity[OPEN

    PubMed Central

    Husbands, Aman Y.; Benkovics, Anna H.; Nogueira, Fabio T.S.; Lodha, Mukesh; Timmermans, Marja C.P.

    2015-01-01

    Flattened leaf architecture is not a default state but depends on positional information to precisely coordinate patterns of cell division in the growing primordium. This information is provided, in part, by the boundary between the adaxial (top) and abaxial (bottom) domains of the leaf, which are specified via an intricate gene regulatory network whose precise circuitry remains poorly defined. Here, we examined the contribution of the ASYMMETRIC LEAVES (AS) pathway to adaxial-abaxial patterning in Arabidopsis thaliana and demonstrate that AS1-AS2 affects this process via multiple, distinct regulatory mechanisms. AS1-AS2 uses Polycomb-dependent and -independent mechanisms to directly repress the abaxial determinants MIR166A, YABBY5, and AUXIN RESPONSE FACTOR3 (ARF3), as well as a nonrepressive mechanism in the regulation of the adaxial determinant TAS3A. These regulatory interactions, together with data from prior studies, lead to a model in which the sequential polarization of determinants, including AS1-AS2, explains the establishment and maintenance of adaxial-abaxial leaf polarity. Moreover, our analyses show that the shared repression of ARF3 by the AS and trans-acting small interfering RNA (ta-siRNA) pathways intersects with additional AS1-AS2 targets to affect multiple nodes in leaf development, impacting polarity as well as leaf complexity. These data illustrate the surprisingly multifaceted contribution of AS1-AS2 to leaf development showing that, in conjunction with the ta-siRNA pathway, AS1-AS2 keeps the Arabidopsis leaf both flat and simple. PMID:26589551

  11. Degradation of monumental bronzes

    NASA Astrophysics Data System (ADS)

    Meakin, John D.; Ames, David L.; Dolske, Donald A.

    Under the United States National Acid Precipitation Assessment Program a metallurgical and corrosion study has been made of sample of the 50 bronze replicas of the Hiker statue cast by the Gorham Foundry, Providence, Rhode Island, between 1906 and 1966. To study corrosion damage on a microscopic scale a technique was developed to take molds of selected features on the statue. The molds were examined by optical and scanning electron microscopy and surface profilometry. The overall approach has the potential for quantitatively monitoring the local corrosion at selected sites over a period of years and also characterizing the impact of conservation procedures. In a parallel research program, run-off samples were taken from selected Brigade Markers in a series of bronze tablets in the Gettysburg National Military Park; parallel rainwater samples were collected. Analysis for pH, metal content and various ion species in the run off yields information on the total rate of corrosion as a function of dry and wet precipitation.

  12. 75 FR 14257 - Pricing for Bronze Medals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-24

    .... ACTION: Notice. SUMMARY: The United States Mint is announcing the price of the 1\\5/16\\- inch bronze medals, 1\\1/2\\-inch bronze medals and three-inch bronze medals. Beginning March 25, 2010, the 1\\5/16\\-inch bronze medals will be priced at $5.50 each; 1\\1/2\\-inch bronze medals will be priced at $6.00...

  13. Leaf Associated Microbial Activities in a Stream Affected by Acid Mine Drainage

    NASA Astrophysics Data System (ADS)

    Schlief, Jeanette

    2004-11-01

    Microbial activity was assessed on birch leaves and plastic strips during 140 days of exposure at three sites in an acidic stream of the Lusatian post-mining landscape, Germany. The sites differed in their degrees of ochre deposition and acidification. The aim of the study was (1) to follow the microbial activities during leaf colonization, (2) to compare the effect of different environmental conditions on leaf associated microbial activities, and (3) to test the microbial availability of leaf litter in acidic mining waters. The activity peaked after 49 days and subsequently decreased gradually at all sites. A formation of iron plaques on leaf surfaces influenced associated microbial activity. It seemed that these plaques inhibit the microbial availability of leaf litter and serve as a microbial habitat by itself. (

  14. Rolling-leaf14 is a 2OG-Fe (II) oxygenase family protein that modulates rice leaf rolling by affecting secondary cell wall formation in leaves.

    PubMed

    Fang, Likui; Zhao, Fangming; Cong, Yunfei; Sang, Xianchun; Du, Qing; Wang, Dezhong; Li, Yunfeng; Ling, Yinghua; Yang, Zhenglin; He, Guanghua

    2012-06-01

    As an important agronomic trait, leaf rolling in rice (Oryza sativa L.) has attracted much attention from plant biologists and breeders. Moderate leaf rolling increases the amount of photosynthesis in cultivars and hence raises grain yield. Here, we describe the map-based cloning of the gene RL14, which was found to encode a 2OG-Fe (II) oxygenase of unknown function. rl14 mutant plants had incurved leaves because of the shrinkage of bulliform cells on the adaxial side. In addition, rl14 mutant plants displayed smaller stomatal complexes and decreased transpiration rates, as compared with the wild type. Defective development could be rescued functionally by the expression of wild-type RL14. RL14 was transcribed in sclerenchymatous cells in leaves that remained wrapped inside the sheath. In mature leaves, RL14 accumulated mainly in the mesophyll cells that surround the vasculature. Expression of genes related to secondary cell wall formation was affected in rl14-1 mutants, and cellulose and lignin content were altered in rl14-1 leaves. These results reveal that the RL14 gene affects water transport in leaves by affecting the composition of the secondary cell wall. This change in water transport results in water deficiency, which is the major reason for the abnormal shape of the bulliform cells. PMID:22329407

  15. Herbivore-induced maize leaf volatiles affect attraction and feeding behavior of Spodoptera littoralis caterpillars.

    PubMed

    von Mérey, Georg E; Veyrat, Nathalie; D'Alessandro, Marco; Turlings, Ted C J

    2013-01-01

    Plants under herbivore attack emit volatile organic compounds (VOCs) that can serve as foraging cues for natural enemies. Adult females of Lepidoptera, when foraging for host plants to deposit eggs, are commonly repelled by herbivore-induced VOCs, probably to avoid competition and natural enemies. Their larval stages, on the other hand, have been shown to be attracted to inducible VOCs. We speculate that this contradicting behavior of lepidopteran larvae is due to a need to quickly find a new suitable host plant if they have fallen to the ground. However, once they are on a plant they might avoid the sites with fresh damage to limit competition and risk of cannibalism by conspecifics, as well as exposure to natural enemies. To test this we studied the effect of herbivore-induced VOCs on the attraction of larvae of the moth Spodoptera littoralis and on their feeding behavior. The experiments further considered the importance of previous feeding experience on the responses of the larvae. It was confirmed that herbivore-induced VOCs emitted by maize plants are attractive to the larvae, but exposure to the volatiles decreased the growth rate of caterpillars at early developmental stages. Larvae that had fed on maize previously were more attracted by VOCs of induced maize than larvae that had fed on artificial diet. At relatively high concentrations synthetic green leaf volatiles, indicative of fresh damage, also negatively affected the growth rate of caterpillars, but not at low concentrations. In all cases, feeding by the later stages of the larvae was not affected by the VOCs. The results are discussed in the context of larval foraging behavior under natural conditions, where there may be a trade-off between using available host plant signals and avoiding competitors and natural enemies. PMID:23825475

  16. Leaf biomechanical properties in Arabidopsis thaliana polysaccharide mutants affect drought survival.

    PubMed

    Balsamo, Ronald; Boak, Merewyn; Nagle, Kayla; Peethambaran, Bela; Layton, Bradley

    2015-11-26

    Individual sugars are the building blocks of cell wall polysaccharides, which in turn comprise a plant׳s overall architectural structure. But which sugars play the most prominent role in maintaining a plant׳s mechanical stability during large cellular deformations induced by drought? We investigated the individual contributions of several genes that are involved in the synthesis of monosaccharides which are important for cell wall structure. We then measured drought tolerance and mechanical integrity during simulated drought in Arabidopsis thaliana. To assess mechanical properties, we designed a small-scale tensile tester for measuring failure strain, ultimate tensile stress, work to failure, toughness, and elastic modulus of 6-week-old leaves in both hydrated and drought-simulated states. Col-0 mutants used in this study include those deficient in lignin, cellulose, components of hemicellulose such as xylose and fucose, the pectic components arabinose and rhamnose, as well as mutants with enhanced arabinose and total pectin content. We found that drought tolerance is correlated to the mechanical and architectural stability of leaves as they experience dehydration. Of the mutants, S096418 with mutations for reduced xylose and galactose was the least drought tolerant, while the arabinose-altered CS8578 mutants were the least affected by water loss. There were also notable correlations between drought tolerance and mechanical properties in the diminished rhamnose mutant, CS8575 and the dehydrogenase-disrupted S120106. Our findings suggest that components of hemicellulose and pectins affect leaf biomechanical properties and may play an important role in the ability of this model system to survive drought. PMID:26520913

  17. Corrosion and Preservation of Bronze Artifacts.

    ERIC Educational Resources Information Center

    Walker, Robert

    1980-01-01

    Reviews chemical information relating to the corrosion of bronze artifacts. Properties of copper alloys are reviewed, with a thorough discussion of the specialized properties of bronze. Techniques to reduce or eliminate corrosion are listed. (CS)

  18. 21 CFR 73.1646 - Bronze powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Bronze powder. 73.1646 Section 73.1646 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1646 Bronze powder. (a) Identity. (1) The color additive bronze powder is a very fine metallic...

  19. 21 CFR 73.1646 - Bronze powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Bronze powder. 73.1646 Section 73.1646 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1646 Bronze powder. (a) Identity. (1) The color additive bronze powder is a very fine metallic powder prepared from alloys consisting principally of...

  20. 21 CFR 73.1646 - Bronze powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Bronze powder. 73.1646 Section 73.1646 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1646 Bronze powder. (a) Identity. (1) The color additive bronze powder is a very fine metallic...

  1. 21 CFR 73.1646 - Bronze powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Bronze powder. 73.1646 Section 73.1646 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1646 Bronze powder. (a) Identity. (1) The color additive bronze powder is a very fine metallic powder prepared from alloys consisting principally of...

  2. 21 CFR 73.1646 - Bronze powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Bronze powder. 73.1646 Section 73.1646 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1646 Bronze powder. (a) Identity. (1) The color additive bronze powder is a very fine metallic powder prepared from alloys consisting principally of...

  3. 21 CFR 73.2646 - Bronze powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Bronze powder. 73.2646 Section 73.2646 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2646 Bronze powder. (a) Identity and specifications. The color additive bronze powder shall conform in identity and specifications to the requirements of §...

  4. 21 CFR 73.2646 - Bronze powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Bronze powder. 73.2646 Section 73.2646 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2646 Bronze powder. (a) Identity and specifications. The color additive bronze powder shall conform in identity and specifications to the requirements of §...

  5. KINETICS OF LEAF TEMPERATURE FLUCTUATION AFFECT ISOPRENE EMISSION FROM RED OAK (QUERCUS RUBRA) LEAVES

    EPA Science Inventory

    Because the rate of isoprene (2-methyl-1,3-butadiene) emission from plants is highly temperature-dependent, we investigated the natural fluctuations on leaf temperature and the effects of rapid temperature change on isoprene emission of red oak (Quercus rubra L.) leaves at the to...

  6. Dynamic spatial patterns of leaf traits affect total respiration on the crown scale

    NASA Astrophysics Data System (ADS)

    Wang, Xiaolin; Zhou, Hongxuan; Han, Fengsen; Li, Yuanzheng; Hu, Dan

    2016-05-01

    Temporal and spatial variations of leaf traits caused conflicting conclusions and great estimating errors of total carbon budget on crown scales. However, there is no effective method to quantitatively describe and study heterogeneous patterns of crowns yet. In this study, dynamic spatial patterns of typical ecological factors on crown scales were investigated during two sky conditions, and CEZs (crown ecological zones) method was developed for spatial crown zoning, within which leaf traits were statistically unchanged. The influencing factors on hourly and spatial variations of leaf dark respiration (Rd) were analysed, and total crown respiration (Rt) was estimated based on patterns of CEZs. The results showed that dynamic spatial patterns of air temperature and light intensity changed significantly by CEZs in special periods and positions, but not continuously. The contributions of influencing factors on variations of Rd changed with crown depth and sky conditions, and total contributions of leaf structural and chemical traits were higher during sunny days than ecological factors, but lower during cloudy days. The estimated errors of Rt may be obviously reduced with CEZs. These results provided some references for scaling from leaves to crown, and technical foundations for expanding lab-control experiments to open field ones.

  7. Dynamic spatial patterns of leaf traits affect total respiration on the crown scale

    PubMed Central

    Wang, Xiaolin; Zhou, Hongxuan; Han, Fengsen; Li, Yuanzheng; Hu, Dan

    2016-01-01

    Temporal and spatial variations of leaf traits caused conflicting conclusions and great estimating errors of total carbon budget on crown scales. However, there is no effective method to quantitatively describe and study heterogeneous patterns of crowns yet. In this study, dynamic spatial patterns of typical ecological factors on crown scales were investigated during two sky conditions, and CEZs (crown ecological zones) method was developed for spatial crown zoning, within which leaf traits were statistically unchanged. The influencing factors on hourly and spatial variations of leaf dark respiration (Rd) were analysed, and total crown respiration (Rt) was estimated based on patterns of CEZs. The results showed that dynamic spatial patterns of air temperature and light intensity changed significantly by CEZs in special periods and positions, but not continuously. The contributions of influencing factors on variations of Rd changed with crown depth and sky conditions, and total contributions of leaf structural and chemical traits were higher during sunny days than ecological factors, but lower during cloudy days. The estimated errors of Rt may be obviously reduced with CEZs. These results provided some references for scaling from leaves to crown, and technical foundations for expanding lab-control experiments to open field ones. PMID:27225586

  8. Dynamic spatial patterns of leaf traits affect total respiration on the crown scale.

    PubMed

    Wang, Xiaolin; Zhou, Hongxuan; Han, Fengsen; Li, Yuanzheng; Hu, Dan

    2016-01-01

    Temporal and spatial variations of leaf traits caused conflicting conclusions and great estimating errors of total carbon budget on crown scales. However, there is no effective method to quantitatively describe and study heterogeneous patterns of crowns yet. In this study, dynamic spatial patterns of typical ecological factors on crown scales were investigated during two sky conditions, and CEZs (crown ecological zones) method was developed for spatial crown zoning, within which leaf traits were statistically unchanged. The influencing factors on hourly and spatial variations of leaf dark respiration (Rd) were analysed, and total crown respiration (Rt) was estimated based on patterns of CEZs. The results showed that dynamic spatial patterns of air temperature and light intensity changed significantly by CEZs in special periods and positions, but not continuously. The contributions of influencing factors on variations of Rd changed with crown depth and sky conditions, and total contributions of leaf structural and chemical traits were higher during sunny days than ecological factors, but lower during cloudy days. The estimated errors of Rt may be obviously reduced with CEZs. These results provided some references for scaling from leaves to crown, and technical foundations for expanding lab-control experiments to open field ones. PMID:27225586

  9. The Liguleless narrow mutation affects proximal distal signaling and leaf growth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    How cells acquire competence to differentiate according to position is an essential question in developmental biology. Maize leaves provide a unique opportunity to study positional information. In the developing leaf primordium, a line is drawn across a field of seemingly identical cells. Above the ...

  10. Genome-wide association study of maize identifies genes affecting leaf architecture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    U.S. maize yield has increased eightfold in the past 80 years with half of the improvement attributed to genetics. Changes in maize leaf angle and size provided a basis for more efficient light capture as plant densities increased. Through a genome wide association study (GWAS) of the maize nested a...

  11. Leaf litter quality affects aquatic insect emergence: contrasting patterns from two foundation trees.

    PubMed

    Compson, Zacchaeus G; Adams, Kenneth J; Edwards, Joeseph A; Maestas, Jesse M; Whitham, Thomas G; Marks, Jane C

    2013-10-01

    Reciprocal subsidies between rivers and terrestrial habitats are common where terrestrial leaf litter provides energy to aquatic invertebrates while emerging aquatic insects provide energy to terrestrial predators (e.g., birds, lizards, spiders). We examined how aquatic insect emergence changed seasonally with litter from two foundation riparian trees, whose litter often dominates riparian streams of the southwestern United States: Fremont (Populus fremontii) and narrowleaf (Populus angustifolia) cottonwood. P. fremontii litter is fast-decomposing and lower in defensive phytochemicals (i.e., condensed tannins, lignin) relative to P. angustifolia. We experimentally manipulated leaf litter from these two species by placing them in leaf enclosures with emergence traps attached in order to determine how leaf type influenced insect emergence. Contrary to our initial predictions, we found that packs with slow-decomposing leaves tended to support more emergent insects relative to packs with fast-decomposing leaves. Three findings emerged. Firstly, abundance (number of emerging insects m(-2) day(-1)) was 25% higher on narrowleaf compared to Fremont leaves for the spring but did not differ in the fall, demonstrating that leaf quality from two dominant trees of the same genus yielded different emergence patterns and that these patterns changed seasonally. Secondly, functional feeding groups of emerging insects differed between treatments and seasons. Specifically, in the spring collector-gatherer abundance and biomass were higher on narrowleaf leaves, whereas collector-filterer abundance and biomass were higher on Fremont leaves. Shredder abundance and biomass were higher on narrowleaf leaves in the fall. Thirdly, diversity (Shannon's H') was higher on Fremont leaves in the spring, but no differences were found in the fall, showing that fast-decomposing leaves can support a more diverse, complex emergent insect assemblage during certain times of the year. Collectively, these

  12. Hormonal activity in detached lettuce leaves as affected by leaf water content.

    PubMed

    Aharoni, N; Blumenfeld, A; Richmond, A E

    1977-06-01

    The interrelationship between water deficiency and hormonal makeup in plants was investigated in detached leaves of romaine lettuce (Lactuca sativa L. cv. ;Hazera Yellow'). Water stress was imposed by desiccating the leaves for several hours in light or darkness at different air temperatures and relative humidity. In the course of desiccation, a rise in abscisic acid content and a decline in gibberellin and cytokinin activity were observed by gas-liquid chromatography, by both the barley endosperm bioassay and radioimmunoassay and by the soybean callus bioassay. Gibberellin activity began to decline in the stressed leaves before the rise in abscisic acid, the rate of this decline being positively correlated with the rate of increase in leaf water saturation deficit. Recovery from water stress was effected by immersing the leaf petioles in water while exposing the blades to high relative humidity. This resulted in a decrease in leaf water saturation deficit, a reduction in abscisic acid content, and an increase in gibberellin and cytokinin activity.Application of abscisic acid to the leaves caused partial stomatal closure in turgid lettuce leaves, whereas treatment with gibberellic acid and kinetin of such leaves had no effect on the stomatal aperture. In desiccating leaves, however, gibberellic acid and kinetin treatment considerably retarded stomatal closure, thus enhancing the increase in leaf water saturation deficit. These results suggest that the effect of desiccation in changing leaf hormonal make-up, i.e. a rapid increase in abscisic acid and a decrease in both cytokinin and gibberellin activity, is related to a mechanism designed to curtail water loss under conditions inducing water deficiency. PMID:16660015

  13. Leaf surface chemicals fromNicotiana affecting germination ofPeronospora tabacina (adam) sporangia.

    PubMed

    Kennedy, B S; Nielsen, M T; Severson, R F; Sisson, V A; Stephenson, M K; Jackson, D M

    1992-09-01

    A bioassay was used to evaluate the effects of cuticular leaf components, isolated fromN. tabacum, N. glutinosa (accessions 24 and 24a), and 23other Nicotiana species, on germinationof P. tabacina (blue mold). The leaf surface compounds includedα- andβ-4,8,13,-duvatriene-l,3-diols (DVT-diols), (13-E)-labda-13-ene-8α-,15-diol (labdenediol), (12-Z)-labda-12,14-diene-8α-ol (cis-abienol), (13-R)-labda-8,14-diene-13-ol (manool), 2-hydroxymanool, a mixture of (13-R)-labda-14-ene-8α,13-diol (sclareol), and (13-S)-labda-14-ene-8α,13-diol (episclareol), and various glucose and/or sucrose ester isolates. The above in acetone were applied onto leaf disks of the blue moldsusceptibleN. tabacum cv. TI 1406, which was then inoculated with blue mold sporangia. Estimated IC50 values (inhibitory concentration) were 3.0μg/cm(2) forα-DVT-diol, 2.9μ/cm(2) forβ-DVT-diol, 0.4μg/cm(2) for labdenediol and 4.7μg/cm(2) for the sclareol mixture. Manool, 2-hydroxymanool, andcis-abienol at application rates up to 30μg/cm(2) had little or no effect on sporangium germination. Glucose and/or sucrose ester isolates from the cuticular leaf extracts of 23Nicotiana species and three different fractions fromN. bigelovii were also evaluated for antimicrobial activity at a concentration of 30μg/cm(2). Germination was inhibited by >20% when exposed to sugar esters isolated fromN. acuminata, N. benthamiana, N. attenuata, N. clevelandii, andN. miersii, and accessions 10 and 12 ofN. bigelovii. These results imply that a number of compounds may influence resistance to blue mold in tobacco. PMID:24254279

  14. Leaf damage and gender but not flower damage affect female fitness in Nemophila menziesii (Hydrophyllaceae).

    PubMed

    McCall, Andrew C

    2007-03-01

    Researchers can answer questions about the evolution or maintenance of separate sexes using dioecious plant systems. Because females in these species typically put more resources into reproductive effort than male plants, researchers have hypothesized that females may be less tolerant of the stresses found in marginal habitats. Herbivory can act as a biotic stressor that reduces resources in plants much like a marginal habitat can. Females may be limited by resources, and may thus be less tolerant to herbivory than males. Here, I explore the relationships between florivory, leaf herbivory, and gender in a gynodioecious, annual plant, Nemophila menziesii (Hydrophyllaceae, senso lato). I performed a crossed design experiment examining the main effects and interactions of plant gender, artificial leaf damage, and artificial flower damage on components of female plant fitness. Leaf damage decreased fruit set and females made significantly more fruit than hermaphrodites. However, contrary to theory, I found little evidence for a gender by damage interaction for either type of artificial herbivory. Based on these results, I propose more work exploring the effects of both source and sink damage in dioecious species to help elucidate where and when different sexual morphs are favored by natural selection. PMID:21636414

  15. How environmental conditions affect canopy leaf-level photosynthesis in four deciduous tree species

    SciTech Connect

    Bassow, S.L.; Bazzaz, F.A.

    1998-12-01

    Species composition of temperate forests vary with successional age and seems likely to change in response to significant global climate change. Because photosynthesis rates in co-occurring tree species can differ in their sensitivity to environmental conditions, these changes in species composition are likely to alter the carbon dynamics of temperate forests. To help improve their understanding of such atmosphere-biosphere interactions, the authors explored changes in leaf-level photosynthesis in a 60--70 yr old temperate mixed-deciduous forest in Petersham, Massachusetts (USA). Diurnally and seasonally varying environmental conditions differentially influenced in situ leaf-level photosynthesis rates in the canopies of four mature temperate deciduous tree species: red oak (Quercus rubra), red maple (Acer rubrum), white birch (Betula papyrifera), and yellow birch (Betula alleghaniensis). The authors measured in situ photosynthesis at two heights within the canopies through a diurnal time course on 7 d over two growing seasons. They simultaneously measured a suite of environmental conditions surrounding the leaf at the time of each measurement. The authors used path analysis to examine the influence of environmental factors on in situ photosynthesis in the tree canopies.

  16. Gold, Silver and Bronze Citations.

    ERIC Educational Resources Information Center

    American School & University, 2003

    2003-01-01

    Presents the gold, silver, and bronze winners of a competition, which judged the most outstanding learning environments at educational institutions nationwide. Jurors spent two days reviewing projects, focusing on concepts and ideas that made them exceptional. For each citation, the article offers information on the firm, client, total area, total…

  17. Ancient Chinese Bronzes: Teacher's Packet.

    ERIC Educational Resources Information Center

    Smithsonian Institution, Washington, DC. Arthur M. Sackler Gallery.

    The focus of this teacher's packet is the bronze vessels made for the kings and great families of the early Chinese dynasties between 1700 B.C. and 200 A.D. The materials in the guide are intended for use by teachers and students visiting the exhibition, "The Arts of China," at the Arthur M. Sackler Gallery of the Smithsonian Institution in…

  18. Oral administration of leaf extracts of Momordica charantia affect reproductive hormones of adult female Wistar rats

    PubMed Central

    Adewale, Osonuga Odusoga; Oduyemi, Osonuga Ifabunmi; Ayokunle, Osonuga

    2014-01-01

    Objective To determine the effect of graded doses of aqueous leaf extracts of Momordica charantia on fertility hormones of female albino rats. Methods Twenty adult, healthy, female Wistar rats were divided into four groups: low dose (LD), moderate dose (MD) and high dose (HD) groups which received 12.5 g, 25.0 g, 50.0 g of the leaf extract respectively and control group that was given with water ad libatum. Result Estrogen levels reduced by 6.40 nmol/L, 10.80 nmol/L and 28.00 nmol/L in the LD, MD and HD groups respectively while plasma progesterone of rats in the LD, MD and HD groups reduced by 24.20 nmol/L, 40.8 nmol/L and 59.20 nmol/L respectively. Conclusion Our study has shown that the antifertility effect of Momordica charantia is achieved in a dose dependent manner. Hence, cautious use of such medication should be advocated especially when managing couples for infertility. PMID:25183143

  19. Phragmites australis and Quercus robur leaf extracts affect antioxidative system and photosynthesis of Ceratophyllum demersum.

    PubMed

    Kamara, Sheku; Pflugmacher, Stephan

    2007-06-01

    During senescence, leaves are deposited on aquatic bodies and decay under water releasing chemical substances that might exert physiological stress to aquatic organisms. Leaf litter alone contributes 30% of the total dissolved organic carbon (DOC) in streams. We investigated the impact of leaves extract from Phragmites australis and Quercus robur on the antioxidative system and photosynthetic rate of the aquatic macrophyte Ceratophyllum demersum exposed for 24h. Rate of photosynthetic oxygen release and antioxidant enzyme activity (glutathione S-transferases, glutathione reductases and peroxidases) as well as lipid peroxidation in C. demersum were measured. Significant (P<0.01) elevations of antioxidative enzyme activity in C. demersum which tends to plateau at high DOC concentrations were observed. There was no detectable effect on lipid peroxidation. A significant dose-dependent reduction in photosynthetic oxygen production was measured. PMID:16996134

  20. Neutron Imaging of Archaeological Bronzes

    SciTech Connect

    Ryzewski, Krysta; Herringer, Susan; Bilheux, Hassina Z; Walker, Lakeisha MH; Sheldon, Brian; Voisin, Sophie; Bilheux, Jean-Christophe; Finocchiaro, Vincenzo

    2013-01-01

    This article presents the initial results of 2-D and 3-D neutron imaging of bronze artifacts using the CG-1D prototype beamline at the High Flux Isotope Reactor (HFIR) located at the Oak Ridge National Laboratory (ORNL). Neutron imaging is a non-destructive technique capable of producing unprecedented three-dimensional information on archaeomaterials, including qualitative, quantitative, and visual data on impurities, composition change, voids, and c

  1. Differences in the sensitivity of fungi and bacteria to season and invertebrates affect leaf litter decomposition in a Mediterranean stream.

    PubMed

    Mora-Gómez, Juanita; Elosegi, Arturo; Duarte, Sofia; Cássio, Fernanda; Pascoal, Cláudia; Romaní, Anna M

    2016-08-01

    Microorganisms are key drivers of leaf litter decomposition; however, the mechanisms underlying the dynamics of different microbial groups are poorly understood. We investigated the effects of seasonal variation and invertebrates on fungal and bacterial dynamics, and on leaf litter decomposition. We followed the decomposition of Populus nigra litter in a Mediterranean stream through an annual cycle, using fine and coarse mesh bags. Irrespective of the season, microbial decomposition followed two stages. Initially, bacterial contribution to total microbial biomass was higher compared to later stages, and it was related to disaccharide and lignin degradation; in a later stage, bacteria were less important and were associated with hemicellulose and cellulose degradation, while fungi were related to lignin decomposition. The relevance of microbial groups in decomposition differed among seasons: fungi were more important in spring, whereas in summer, water quality changes seemed to favour bacteria and slowed down lignin and hemicellulose degradation. Invertebrates influenced litter-associated microbial assemblages (especially bacteria), stimulated enzyme efficiencies and reduced fungal biomass. We conclude that bacterial and fungal assemblages play distinctive roles in microbial decomposition and differ in their sensitivity to environmental changes, ultimately affecting litter decomposition, which might be particularly relevant in highly seasonal ecosystems, such as intermittent streams. PMID:27288197

  2. Vertical Chlorophyll Canopy Structure Affects the Remote Sensing Based Predictability of LAI, Chlorophyll and Leaf Nitrogen in Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Boegh, E.; Houborg, R.; Bienkowski, J.; Braban, C. F.; Dalgaard, T.; van Dijk, N.; Dragosits, U.; Holmes, E.; Magliulo, V.; Schelde, K.; Di Tommasi, P.; Vitale, L.; Theobald, M.; Cellier, P.; Sutton, M.

    2012-12-01

    SVIs require field data for empirical model building, the REGFLEC model was applied without calibration. LAI and SPAD meter data were measured in 93 fields representing 10 crop types of the five European landscapes. SPAD meter data were measured at five canopy height levels and converted to CHL and N using laboratory calibration. The data showed strong vertical leaf chlorophyll gradient profiles in 20 % of fields. This affected the predictability of SVIs and REGFLEC. However, selecting only homogeneous canopies with uniform CHL distributions as reference data for statistical evaluation, significant predictions were achieved for all landscapes, by all methods, with the best overall results given by REGFLEC. Predictabilities of SVIs and REGFLEC simulations improved when constrained to single land use categories across the European landscapes, reflecting sensitivity to canopy structures, and predictabilities further improved when constrained to local (10 x 10 km2) landscapes, thereby reflecting sensitivity to local environmental conditions. The Enhanced Vegetation Index-2 tended to be the best method in landscapes with high vegetation densities, REGFLEC worked best in a landscape with large contrasts in vegetation density, and the Simple Ratio worked best in a landscape characterized by low vegetation density.

  3. Oleuropein-Enriched Olive Leaf Extract Affects Calcium Dynamics and Impairs Viability of Malignant Mesothelioma Cells.

    PubMed

    Marchetti, Carla; Clericuzio, Marco; Borghesi, Barbara; Cornara, Laura; Ribulla, Stefania; Gosetti, Fabio; Marengo, Emilio; Burlando, Bruno

    2015-01-01

    Malignant mesothelioma is a poor prognosis cancer in urgent need of alternative therapies. Oleuropein, the major phenolic of olive tree (Olea europaea L.), is believed to have therapeutic potentials for various diseases, including tumors. We obtained an oleuropein-enriched fraction, consisting of 60% w/w oleuropein, from olive leaves, and assessed its effects on intracellular Ca(2+) and cell viability in mesothelioma cells. Effects of the oleuropein-enriched fraction on Ca(2+) dynamics and cell viability were studied in the REN mesothelioma cell line, using fura-2 microspectrofluorimetry and MTT assay, respectively. Fura-2-loaded cells, transiently exposed to the oleuropein-enriched fraction, showed dose-dependent transient elevations of cytosolic Ca(2+) concentration ([Ca(2+)]i). Application of standard oleuropein and hydroxytyrosol, and of the inhibitor of low-voltage T-type Ca(2+) channels NNC-55-0396, suggested that the effect is mainly due to oleuropein acting through its hydroxytyrosol moiety on T-type Ca(2+) channels. The oleuropein-enriched fraction and standard oleuropein displayed a significant antiproliferative effect, as measured on REN cells by MTT cell viability assay, with IC50 of 22 μg/mL oleuropein. Data suggest that our oleuropein-enriched fraction from olive leaf extract could have pharmacological application in malignant mesothelioma anticancer therapy, possibly by targeting T-type Ca(2+) channels and thereby dysregulating intracellular Ca(2+) dynamics. PMID:26693247

  4. Oleuropein-Enriched Olive Leaf Extract Affects Calcium Dynamics and Impairs Viability of Malignant Mesothelioma Cells

    PubMed Central

    Marchetti, Carla; Clericuzio, Marco; Borghesi, Barbara; Cornara, Laura; Ribulla, Stefania; Gosetti, Fabio; Marengo, Emilio; Burlando, Bruno

    2015-01-01

    Malignant mesothelioma is a poor prognosis cancer in urgent need of alternative therapies. Oleuropein, the major phenolic of olive tree (Olea europaea L.), is believed to have therapeutic potentials for various diseases, including tumors. We obtained an oleuropein-enriched fraction, consisting of 60% w/w oleuropein, from olive leaves, and assessed its effects on intracellular Ca2+ and cell viability in mesothelioma cells. Effects of the oleuropein-enriched fraction on Ca2+ dynamics and cell viability were studied in the REN mesothelioma cell line, using fura-2 microspectrofluorimetry and MTT assay, respectively. Fura-2-loaded cells, transiently exposed to the oleuropein-enriched fraction, showed dose-dependent transient elevations of cytosolic Ca2+ concentration ([Ca2+]i). Application of standard oleuropein and hydroxytyrosol, and of the inhibitor of low-voltage T-type Ca2+ channels NNC-55-0396, suggested that the effect is mainly due to oleuropein acting through its hydroxytyrosol moiety on T-type Ca2+ channels. The oleuropein-enriched fraction and standard oleuropein displayed a significant antiproliferative effect, as measured on REN cells by MTT cell viability assay, with IC50 of 22 μg/mL oleuropein. Data suggest that our oleuropein-enriched fraction from olive leaf extract could have pharmacological application in malignant mesothelioma anticancer therapy, possibly by targeting T-type Ca2+ channels and thereby dysregulating intracellular Ca2+ dynamics. PMID:26693247

  5. The bacterial pathogen Xylella fastidiosa affects the leaf ionome of plant hosts during infection.

    PubMed

    De La Fuente, Leonardo; Parker, Jennifer K; Oliver, Jonathan E; Granger, Shea; Brannen, Phillip M; van Santen, Edzard; Cobine, Paul A

    2013-01-01

    Xylella fastidiosa is a plant pathogenic bacterium that lives inside the host xylem vessels, where it forms biofilm believed to be responsible for disrupting the passage of water and nutrients. Here, Nicotiana tabacum was infected with X. fastidiosa, and the spatial and temporal changes in the whole-leaf ionome (i.e. the mineral and trace element composition) were measured as the host plant transitioned from healthy to diseased physiological status. The elemental composition of leaves was used as an indicator of the physiological changes in the host at a specific time and relative position during plant development. Bacterial infection was found to cause significant increases in concentrations of calcium prior to the appearance of symptoms and decreases in concentrations of phosphorous after symptoms appeared. Field-collected leaves from multiple varieties of grape, blueberry, and pecan plants grown in different locations over a four-year period in the Southeastern US showed the same alterations in Ca and P. This descriptive ionomics approach characterizes the existence of a mineral element-based response to X. fastidiosa using a model system suitable for further manipulation to uncover additional details of the role of mineral elements during plant-pathogen interactions. This is the first report on the dynamics of changes in the ionome of the host plant throughout the process of infection by a pathogen. PMID:23667547

  6. A mutation, tl2, in pea (Pisum sativum L.) affects leaf development only in the heterozygous state.

    PubMed

    Berdnikov, V A; Gorel, F L

    2005-04-01

    After gamma irradiation of pea seeds, a mutation designated as tendril-less2 (tl2) was induced. In the heterozygous state, it transforms tendrils into very narrow leaflets that resemble the heterozygote phenotype of the classic tl mutation. The tendrils of the double heterozygote tl2/+, tl/+ are converted into oval leaflets. Unlike tl, the novel mutation in the homozygous state does not affect tendrils. The leaf phenotype of homozygotes tl2/tl2 and Tl2/Tl2 do not differ in the tl/+ background. However, the anthocyanin pigmentation is strongly suppressed in petals of tl2/tl2 plants. Some hypotheses to explain the unusual phenotypic manifestation of tl2 are suggested. PMID:15714325

  7. Heat-induced electrical signals affect cytoplasmic and apoplastic pH as well as photosynthesis during propagation through the maize leaf.

    PubMed

    Grams, Thorsten E E; Lautner, Silke; Felle, Hubert H; Matyssek, Rainer; Fromm, Jörg

    2009-04-01

    Combining measurements of electric potential and pH with such of chlorophyll fluorescence and leaf gas exchange showed heat stimulation to evoke an electrical signal (propagation speed: 3-5 mm s(-1)) that travelled through the leaf while reducing the net CO(2) uptake rate and the photochemical quantum yield of both photosystems (PS). Two-dimensional imaging analysis of the chlorophyll fluorescence signal of PS II revealed that the yield reduction spread basipetally via the veins through the leaf at a speed of 1.6 +/- 0.3 mm s(-1) while the propagation speed in the intervein region was c. 50 times slower. Propagation of the signal through the veins was confirmed because PS I, which is present in the bundle sheath cells around the leaf vessels, was affected first. Hence, spreading of the signal along the veins represents a path with higher travelling speed than within the intervein region of the leaf lamina. Upon the electrical signal, cytoplasmic pH decreased transiently from 7.0 to 6.4, while apoplastic pH increased transiently from 4.5 to 5.2. Moreover, photochemical quantum yield of isolated chloroplasts was strongly affected by pH changes in the surrounding medium, indicating a putative direct influence of electrical signalling via changes of cytosolic pH on leaf photosynthesis. PMID:19054346

  8. Tree Species Composition and Harvest Intensity Affect Herbivore Density and Leaf Damage on Beech, Fagus sylvatica, in Different Landscape Contexts.

    PubMed

    Mangels, Jule; Blüthgen, Nico; Frank, Kevin; Grassein, Fabrice; Hilpert, Andrea; Mody, Karsten

    2015-01-01

    Most forests are exposed to anthropogenic management activities that affect tree species composition and natural ecosystem processes. Changes in ecosystem processes such as herbivory depend on management intensity, and on regional environmental conditions and species pools. Whereas influences of specific forest management measures have already been addressed for different herbivore taxa on a local scale, studies considering effects of different aspects of forest management across different regions are rare. We assessed the influence of tree species composition and intensity of harvesting activities on arthropod herbivores and herbivore-related damage to beech trees, Fagus sylvatica, in 48 forest plots in three regions of Germany. We found that herbivore abundance and damage to beech trees differed between regions and that - despite the regional differences - density of tree-associated arthropod taxa and herbivore damage were consistently affected by tree species composition and harvest intensity. Specifically, overall herbivore damage to beech trees increased with increasing dominance of beech trees - suggesting the action of associational resistance processes - and decreased with harvest intensity. The density of leaf chewers and mines was positively related to leaf damage, and several arthropod groups responded to beech dominance and harvest intensity. The distribution of damage patterns was consistent with a vertical shift of herbivores to higher crown layers during the season and with higher beech dominance. By linking quantitative data on arthropod herbivore abundance and herbivory with tree species composition and harvesting activity in a wide variety of beech forests, our study helps to better understand the influence of forest management on interactions between a naturally dominant deciduous forest tree and arthropod herbivores. PMID:25938417

  9. Tree Species Composition and Harvest Intensity Affect Herbivore Density and Leaf Damage on Beech, Fagus sylvatica, in Different Landscape Contexts

    PubMed Central

    Mangels, Jule; Blüthgen, Nico; Frank, Kevin; Grassein, Fabrice; Hilpert, Andrea; Mody, Karsten

    2015-01-01

    Most forests are exposed to anthropogenic management activities that affect tree species composition and natural ecosystem processes. Changes in ecosystem processes such as herbivory depend on management intensity, and on regional environmental conditions and species pools. Whereas influences of specific forest management measures have already been addressed for different herbivore taxa on a local scale, studies considering effects of different aspects of forest management across different regions are rare. We assessed the influence of tree species composition and intensity of harvesting activities on arthropod herbivores and herbivore-related damage to beech trees, Fagus sylvatica, in 48 forest plots in three regions of Germany. We found that herbivore abundance and damage to beech trees differed between regions and that – despite the regional differences - density of tree-associated arthropod taxa and herbivore damage were consistently affected by tree species composition and harvest intensity. Specifically, overall herbivore damage to beech trees increased with increasing dominance of beech trees – suggesting the action of associational resistance processes – and decreased with harvest intensity. The density of leaf chewers and mines was positively related to leaf damage, and several arthropod groups responded to beech dominance and harvest intensity. The distribution of damage patterns was consistent with a vertical shift of herbivores to higher crown layers during the season and with higher beech dominance. By linking quantitative data on arthropod herbivore abundance and herbivory with tree species composition and harvesting activity in a wide variety of beech forests, our study helps to better understand the influence of forest management on interactions between a naturally dominant deciduous forest tree and arthropod herbivores. PMID:25938417

  10. TCP14 and TCP15 affect internode length and leaf shape in Arabidopsis

    PubMed Central

    Kieffer, Martin; Master, Vera; Waites, Richard; Davies, Brendan

    2011-01-01

    TCP transcription factors constitute a small family of plant-specific bHLH-containing, DNA-binding proteins that have been implicated in the control of cell proliferation in plants. Despite the significant role that is likely to be played by genes that control cell division in the elaboration of plant architecture, functional analysis of this family by forward and reverse genetics has been hampered by genetic redundancy. Here we show that mutants in two related class I TCP genes display a range of growth-related phenotypes, consistent with their dynamic expression patterns; these phenotypes are enhanced in the double mutant. Together, the two genes influence plant stature by promoting cell division in young internodes. Reporter gene analysis and use of SRDX fusions suggested that TCP14 and TCP15 modulate cell proliferation in the developing leaf blade and specific floral tissues; a role that was not apparent in our phenotypic analysis of single or double mutants. However, when the relevant mutants were subjected to computer-aided morphological analysis of the leaves, the consequences of loss of either or both genes became obvious. The effects on cell proliferation of perturbing the function of TCP14 and TCP15 vary with tissue, as has been suggested for other TCP factors. These findings indicate that the precise elaboration of plant form is dependent on the cumulative influence of many TCP factors acting in a context-dependent fashion. The study highlights the need for advanced methods of phenotypic analysis in order to characterize phenotypes and to construct a dynamic model for TCP gene function. PMID:21668538

  11. 21 CFR 73.2646 - Bronze powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2646 Bronze powder. (a) Identity and specifications. The....1646 (a)(1) and (b). (b) Uses and restrictions. Bronze powder may be safely used in coloring cosmetics generally, including cosmetics intended for use in the area of the eye, in amounts consistent with...

  12. 21 CFR 73.2646 - Bronze powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2646 Bronze powder. (a) Identity and specifications. The....1646 (a)(1) and (b). (b) Uses and restrictions. Bronze powder may be safely used in coloring cosmetics generally, including cosmetics intended for use in the area of the eye, in amounts consistent with...

  13. 21 CFR 73.2646 - Bronze powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2646 Bronze powder. (a) Identity and specifications. The....1646 (a)(1) and (b). (b) Uses and restrictions. Bronze powder may be safely used in coloring cosmetics generally, including cosmetics intended for use in the area of the eye, in amounts consistent with...

  14. Satellite based remote sensing technique as a tool for real time monitoring of leaf retention in natural rubber plantations affected by abnormal leaf fall disease

    NASA Astrophysics Data System (ADS)

    Pradeep, B.; Meti, S.; James, J.

    2014-11-01

    Most parts of the traditional natural rubber growing regions of India, extending from Kanyakumari district of Tamil Nadu in the South to Kasaragod district of Kerala in the North received excess and prolonged rains during 2013. This led to severe incidence of Abnormal Leaf Fall (ALF) disease caused by the fungus, Phytophthora sp. The present study demonstrated the first time use of satellite remote sensing technique to monitor ALF disease by estimating Leaf Area Index (LAI) in natural rubber holdings in near real time. Leaf retention was monitored in between April and December 2012 and 2013 by estimating LAI using MODIS 15A2 product covering rubber holdings spread across all districts in the traditional rubber growing region of the country that was mapped using Resourcesat LISS III 2012 and 2013 data. It was found that as the monsoon advanced, LAI decreased substantially in both years, but the reduction was much more substantial and prolonged in many districts during 2013 than 2012 reflecting increased leaf fall due to ALF disease in 2013. The decline was more pronounced in central and northern Kerala than in the South. Kanyakumari district of Tamil Nadu is generally known to be free from ALF disease, but there was considerable leaf loss due to ALF in June 2012 and June and July 2013 even as the monsoon was unusually severe in 2013. Weighted mean LAI during for the entire period of April to December was estimated as a weighted average of LAI and per cent of total area under rubber in each district in the study area for the two years. This was markedly less in 2013 than 2012. The implications of poor leaf retention for biomass production (net primary productivity), carbon sequestration and rubber yield are discussed.

  15. Edge type affects leaf-level water relations and estimated transpiration of Eucalyptus arenacea.

    PubMed

    Wright, Thomas E; Tausz, Michael; Kasel, Sabine; Volkova, Liubov; Merchant, Andrew; Bennett, Lauren T

    2012-03-01

    While edge effects on tree water relations are well described for closed forests, they remain under-examined in more open forest types. Similarly, there has been minimal evaluation of the effects of contrasting land uses on the water relations of open forest types in highly fragmented landscapes. We examined edge effects on the water relations and gas exchange of a dominant tree (Eucalyptus arenacea Marginson & Ladiges) in an open forest type (temperate woodland) of south-eastern Australia. Edge effects in replicate woodlands adjoined by cleared agricultural land (pasture edges) were compared with those adjoined by 7- to 9-year-old eucalypt plantation with a 25m fire break (plantation edges). Consistent with studies in closed forest types, edge effects were pronounced at pasture edges where photosynthesis, transpiration and stomatal conductance were greater for edge trees than interior trees (75m into woodlands), and were related to greater light availability and significantly higher branch water potentials at woodland edges than interiors. Nonetheless, gas exchange values were only ∼50% greater for edge than interior trees, compared with ∼200% previously found in closed forest types. In contrast to woodlands adjoined by pasture, gas exchange in winter was significantly lower for edge than interior trees in woodlands adjoined by plantations, consistent with shading and buffering effects of plantations on edge microclimate. Plantation edge effects were less pronounced in summer, although higher water use efficiency of edge than interior woodland trees indicated possible competition for water between plantation trees and woodland edge trees in the drier months (an effect that might have been more pronounced were there no firebreak between the two land uses). Scaling up of leaf-level water relations to stand transpiration using a Jarvis-type phenomenological model indicated similar differences between edge types. That is, transpiration was greater at pasture than

  16. Solar UV-B radiation affects leaf quality and insect herbivory in the southern beech tree Nothofagus antarctica.

    PubMed

    Rousseaux, M Cecilia; Julkunen-Tiitto, Riitta; Searles, Peter S; Scopel, Ana L; Aphalo, Pedro J; Ballaré, Carlos L

    2004-03-01

    We examined the effects of solar ultraviolet-B (UV-B) radiation on plant-insect interactions in Tierra del Fuego (55 degrees S), Argentina, an area strongly affected by ozone depletion because of its proximity to Antarctica. Solar UV-B under Nothofagus antarctica branches was manipulated using a polyester plastic film to attenuate UV-B (uvb-) and an Aclar film to provide near-ambient UV-B (uvb+). The plastic films were placed on both north-facing (i.e., high solar radiation in the Southern Hemisphere) and south-facing branches. Insects consumed 40% less leaf area from north- than from south-facing branches, and at least 30% less area from uvb+ branches than from uvb- branches. The reduced herbivory on leaves from uvb+ branches occurred for both branch orientations. Leaf mass per area increased and relative water content decreased on north- versus south-facing branches, while no differences were apparent between the UV-B treatments. Solar UV-B did lead to lower gallic acid concentration and higher flavonoid aglycone concentration in uvb+ leaves relative to uvb- leaves. Both the flavonoid aglycone and quercetin-3-arabinopyranoside were higher on north-facing branches. In laboratory preference experiments, larvae of the dominant insect in the natural community, Geometridae "Brown" (Lepidoptera), consumed less area from field-grown uvb+ leaves than from uvb- leaves in 1996-97, but not in 1997-98. Correlation analyses suggested that the reduction in insect herbivory in the field under solar UV-B may be mediated in part by the UV-B effects on gallic acid and flavonoid aglycone. PMID:14740287

  17. Laser fusing of HVOF thermal sprayed alloy 625 on nickel-aluminum bronze

    SciTech Connect

    Brenna, R.T.; Pugh, J.L.; Denney, P.E.

    1994-12-31

    A preliminary study has been conducted to determine the feasibility of laser fusing alloy 625 onto nickel-aluminum-bronze base metal. Laser fusing was performed by melting a pre-coated surface of alloy 625 that had been applied by the high velocity oxyfuel (HVOF) thermal spray process. The laser fusing was successful in producing a metallurigical bond between alloy 625 and the substrate. Minor modification to the heat-affected zone of the base metal was observed by microhardness measurements, and defect-free interfaces were produced between alloy 625 and nickel-aluminum-bronze by the process. The laser is a high energy density source that can be used for precise thermal processing of materials including surface modification. Laser fusing is the full or partial melting of a coating material that has been previously applied in some fashion to the substrate. Thermal spray coating of nickel-aluminum-bronze material with alloy 625 was conducted at the David Taylor Research Center. Nickel-aluminum-bronze specimens 2 x 3-in. by 1/2-in. thick were coated with alloy 25 utilizing the HVOF equipment. Coating thicknesses of approximately 0.014-in. (0.3 mm) were produced for subsequent laser fusing experiments. A preliminary study has been conducted to determine the feasibility of laser fusing a HVOF thermal sprayed alloy 625 coating onto nickel-aluminum-bronze base metal. Conclusions of this investigation were as follows: (1) Laser fusing was successful in producing a metallurgical bond between HVOF thermal sprayed alloy 625 and the nickel-aluminum-bronze. (2) Only minor microstructural modification to the heat-affected zone of the base metal ws observed by microhardness measurements. (3) Defect-free interfaces were produced between thermal sprayed alloy 625 and nickel-aluminum-bronze by laser fusing.

  18. Natural enemies of Atta vollenweideri (Hymenoptera: Formicidae) leaf-cutter ants negatively affected by synthetic pesticides, chlorpyrifos and fipronil.

    PubMed

    Guillade, Andrea C; Folgarait, Patricia J

    2014-02-01

    In southern South America, Ada vollenweideri Forel (Hymenoptera: Formicidae) is a significant pest of several crops and forestry, also considered to reduce the carrying capacity of pastures. The most usual control method used in Latin America is the application of synthetic pesticides, mainly chlorpyrifos and fipronil. However, no studies have assessed the effects of these agrochemicals on natural enemies of ants. We aimed to evaluate the efficiency of these pesticides on leaf-cutter ants' control and to test their effect on phorid fly parasitoids. Chlorpyrifos failed to exert complete control over ant colonies in the field and was gravely detrimental to specific parasitoids, reducing their percentage of parasitism, pupal survivorship, and adult longevity. Fipronil, however, exerted complete control over the treated colonies. Laboratory tests using both pesticides, either on ants from foraging trails or on pupariae, showed that chlorpyrifos and fipronil decreased larval and pupal survivorship, as well as adult longevity of parasitoids, in comparison to controls. In conclusion, these pesticides will likely affect parasitoids with regard to their reproductive capacity, leading to the decreased levels of natural parasitism observed in the field after treatments. We discuss why neither pesticide should be taken into account for integrated pest management programs. PMID:24665691

  19. A high proportion of blue light increases the photosynthesis capacity and leaf formation rate of Rosa × hybrida but does not affect time to flower opening.

    PubMed

    Terfa, Meseret Tesema; Solhaug, Knut Asbjørn; Gislerød, Hans Ragnar; Olsen, Jorunn Elisabeth; Torre, Sissel

    2013-05-01

    Alterations in light quality affect plant morphogenesis and photosynthetic responses but the effects vary significantly between species. Roses exhibit an irradiance-dependent flowering control but knowledge on light quality responses is scarce. In this study we analyzed, the responses in morphology, photosynthesis and flowering of Rosa × hybrida to different blue (B) light proportions provided by light-emitting diodes (LED, high B 20%) and high pressure sodium (HPS, low B 5%) lamps. There was a strong morphological and growth effect of the light sources but no significant difference in total dry matter production and flowering. HPS-grown plants had significantly higher leaf area and plant height, yet a higher dry weight proportion was allocated to leaves than stems under LED. LED plants showed 20% higher photosynthetic capacity (Amax ) and higher levels of soluble carbohydrates. The increase in Amax correlated with an increase in leaf mass per unit leaf area, higher stomata conductance and CO2 exchange, total chlorophyll (Chl) content per area and Chl a/b ratio. LED-grown leaves also displayed a more sun-type leaf anatomy with more and longer palisade cells and a higher stomata frequency. Although floral initiation occurred at a higher leaf number in LED, the time to open flowers was the same under both light conditions. Thereby the study shows that a higher portion of B light is efficient in increasing photosynthesis performance per unit leaf area, enhancing growth and morphological changes in roses but does not affect the total Dry Matter (DM) production or time to open flower. PMID:23020549

  20. Population genomics of Bronze Age Eurasia.

    PubMed

    Allentoft, Morten E; Sikora, Martin; Sjögren, Karl-Göran; Rasmussen, Simon; Rasmussen, Morten; Stenderup, Jesper; Damgaard, Peter B; Schroeder, Hannes; Ahlström, Torbjörn; Vinner, Lasse; Malaspinas, Anna-Sapfo; Margaryan, Ashot; Higham, Tom; Chivall, David; Lynnerup, Niels; Harvig, Lise; Baron, Justyna; Della Casa, Philippe; Dąbrowski, Paweł; Duffy, Paul R; Ebel, Alexander V; Epimakhov, Andrey; Frei, Karin; Furmanek, Mirosław; Gralak, Tomasz; Gromov, Andrey; Gronkiewicz, Stanisław; Grupe, Gisela; Hajdu, Tamás; Jarysz, Radosław; Khartanovich, Valeri; Khokhlov, Alexandr; Kiss, Viktória; Kolář, Jan; Kriiska, Aivar; Lasak, Irena; Longhi, Cristina; McGlynn, George; Merkevicius, Algimantas; Merkyte, Inga; Metspalu, Mait; Mkrtchyan, Ruzan; Moiseyev, Vyacheslav; Paja, László; Pálfi, György; Pokutta, Dalia; Pospieszny, Łukasz; Price, T Douglas; Saag, Lehti; Sablin, Mikhail; Shishlina, Natalia; Smrčka, Václav; Soenov, Vasilii I; Szeverényi, Vajk; Tóth, Gusztáv; Trifanova, Synaru V; Varul, Liivi; Vicze, Magdolna; Yepiskoposyan, Levon; Zhitenev, Vladislav; Orlando, Ludovic; Sicheritz-Pontén, Thomas; Brunak, Søren; Nielsen, Rasmus; Kristiansen, Kristian; Willerslev, Eske

    2015-06-11

    The Bronze Age of Eurasia (around 3000-1000 BC) was a period of major cultural changes. However, there is debate about whether these changes resulted from the circulation of ideas or from human migrations, potentially also facilitating the spread of languages and certain phenotypic traits. We investigated this by using new, improved methods to sequence low-coverage genomes from 101 ancient humans from across Eurasia. We show that the Bronze Age was a highly dynamic period involving large-scale population migrations and replacements, responsible for shaping major parts of present-day demographic structure in both Europe and Asia. Our findings are consistent with the hypothesized spread of Indo-European languages during the Early Bronze Age. We also demonstrate that light skin pigmentation in Europeans was already present at high frequency in the Bronze Age, but not lactose tolerance, indicating a more recent onset of positive selection on lactose tolerance than previously thought. PMID:26062507

  1. Molecular genetics of growth and development in Populus (Salicaceae). V. Mapping quantitative trait loci affecting leaf variation

    SciTech Connect

    Wu, R.; Bradshaw, H.D. Jr.; Stettler, R.F.

    1997-02-01

    The genetic variation of leaf morphology and development was studied in the 2-yr-old replicated plantation of an interspecific hybrid pedigree of Populus trichocarpa T. & G. and P. deltoides Marsh. via both molecular and quantitative genetic methods. Leaf traits chosen showed pronounced differences between the original parents, including leaf size, shape, orientation, color, structure, petiole size, and petiole cross section. In the F{sub 2} generation, leaf traits were all significantly different among genotypes, but with significant effects due to genotype X crown-position interaction. Variation in leaf pigmentation, petiole length, and petiole length proportion appeared to be under the control of few quantitative trait loci (QTLs). More QTLs were associated with single leaf area, leaf shape, lamina angle, abaxial color, and petiole flatness, and in these traits the number of QTLs varied among crown positions. In general the estimates of QTL numbers from Wright`s biometric method were close to those derived from molecular markers. For those traits with few underlying QTLs, a single marker interval could explain from 30-60% of the observed phenotypic variance. For multigenic traits, certain markers contributed more substantially to the observed variation than others. Genetic cluster analysis showed developmentally related traits to be more strongly associated with each other than with unrelated traits. This finding was also supported by the QTL mapping. For example, the same chromosomal segment of linkage group L seemed to account for 20% of the phenotypic variation of all dimension-related traits, leaf size, petiole length, and midrib angle. In both traits, the P. deltoides alleles had positive effects and were dominant to the P. trichocarpa alleles. Similar relationships were also found for lamina angle, abaxial greenness, and petiole flatness. 72 refs., 3 figs., 2 tabs.

  2. Antiphase Light and Temperature Cycles Affect PHYTOCHROME B-Controlled Ethylene Sensitivity and Biosynthesis, Limiting Leaf Movement and Growth of Arabidopsis1[C][W

    PubMed Central

    Bours, Ralph; van Zanten, Martijn; Pierik, Ronald; Bouwmeester, Harro; van der Krol, Alexander

    2013-01-01

    In the natural environment, days are generally warmer than the night, resulting in a positive day/night temperature difference (+DIF). Plants have adapted to these conditions, and when exposed to antiphase light and temperature cycles (cold photoperiod/warm night [−DIF]), most species exhibit reduced elongation growth. To study the physiological mechanism of how light and temperature cycles affect plant growth, we used infrared imaging to dissect growth dynamics under +DIF and −DIF in the model plant Arabidopsis (Arabidopsis thaliana). We found that −DIF altered leaf growth patterns, decreasing the amplitude and delaying the phase of leaf movement. Ethylene application restored leaf growth in −DIF conditions, and constitutive ethylene signaling mutants maintain robust leaf movement amplitudes under −DIF, indicating that ethylene signaling becomes limiting under these conditions. In response to −DIF, the phase of ethylene emission advanced 2 h, but total ethylene emission was not reduced. However, expression analysis on members of the 1-aminocyclopropane-1-carboxylic acid (ACC) synthase ethylene biosynthesis gene family showed that ACS2 activity is specifically suppressed in the petiole region under −DIF conditions. Indeed, petioles of plants under −DIF had reduced ACC content, and application of ACC to the petiole restored leaf growth patterns. Moreover, acs2 mutants displayed reduced leaf movement under +DIF, similar to wild-type plants under −DIF. In addition, we demonstrate that the photoreceptor PHYTOCHROME B restricts ethylene biosynthesis and constrains the −DIF-induced phase shift in rhythmic growth. Our findings provide a mechanistic insight into how fluctuating temperature cycles regulate plant growth. PMID:23979970

  3. Factors affecting the abundance of leaf-litter arthropods in unburned and thrice-burned seasonally-dry Amazonian forests.

    PubMed

    Silveira, Juliana M; Barlow, Jos; Louzada, Julio; Moutinho, Paulo

    2010-01-01

    Fire is frequently used as a land management tool for cattle ranching and annual crops in the Amazon. However, these maintenance fires often escape into surrounding forests, with potentially severe impacts for forest biodiversity. We examined the effect of experimental fires on leaf-litter arthropod abundance in a seasonally-dry forest in the Brazilian Amazon. The study plots (50 ha each) included a thrice-burned forest and an unburned control forest. Pitfall-trap samples were collected at 160 randomly selected points in both plots, with sampling stratified across four intra-annual replicates across the dry and wet seasons, corresponding to 6, 8, 10 and 12 months after the most recent fire. Arthropods were identified to the level of order (separating Formicidae). In order to better understand the processes that determine arthropod abundance in thrice-burned forests, we measured canopy openness, understory density and litter depth. All arthropod taxa were significantly affected by fire and season. In addition, the interactions between burn treatment and season were highly significant for all taxa but Isoptera. The burned plot was characterized by a more open canopy, lower understory density and shallower litter depth. Hierarchical partitioning revealed that canopy openness was the most important factor explaining arthropod order abundances in the thrice-burned plot, whereas all three environmental variables were significant in the unburned control plot. These results reveal the marked impact of recurrent wildfires and seasonality on litter arthropods in this transitional forest, and demonstrate the overwhelming importance of canopy-openness in driving post-fire arthropod abundance. PMID:20877720

  4. Factors Affecting the Abundance of Leaf-Litter Arthropods in Unburned and Thrice-Burned Seasonally-Dry Amazonian Forests

    PubMed Central

    Silveira, Juliana M.; Barlow, Jos; Louzada, Julio; Moutinho, Paulo

    2010-01-01

    Fire is frequently used as a land management tool for cattle ranching and annual crops in the Amazon. However, these maintenance fires often escape into surrounding forests, with potentially severe impacts for forest biodiversity. We examined the effect of experimental fires on leaf-litter arthropod abundance in a seasonally-dry forest in the Brazilian Amazon. The study plots (50 ha each) included a thrice-burned forest and an unburned control forest. Pitfall-trap samples were collected at 160 randomly selected points in both plots, with sampling stratified across four intra-annual replicates across the dry and wet seasons, corresponding to 6, 8, 10 and 12 months after the most recent fire. Arthropods were identified to the level of order (separating Formicidae). In order to better understand the processes that determine arthropod abundance in thrice-burned forests, we measured canopy openness, understory density and litter depth. All arthropod taxa were significantly affected by fire and season. In addition, the interactions between burn treatment and season were highly significant for all taxa but Isoptera. The burned plot was characterized by a more open canopy, lower understory density and shallower litter depth. Hierarchical partitioning revealed that canopy openness was the most important factor explaining arthropod order abundances in the thrice-burned plot, whereas all three environmental variables were significant in the unburned control plot. These results reveal the marked impact of recurrent wildfires and seasonality on litter arthropods in this transitional forest, and demonstrate the overwhelming importance of canopy-openness in driving post-fire arthropod abundance. PMID:20877720

  5. Standard methods for chemical analysis of special brasses and bronzes

    SciTech Connect

    Not Available

    1980-01-01

    These methods cover procedures for the chemical analysis of the commercial alloys known as copper-base alloy ingots for sand castings, forging rods, bars, and shapes; aluminum brass; manganese bronze; phosphor bronze; copper-silicon alloys; and similar alloys.

  6. BRASS FOUNDRY MACHINE ROOM USED TO MACHINE CAST BRONZE PIECES ...

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

    BRASS FOUNDRY MACHINE ROOM USED TO MACHINE CAST BRONZE PIECES FOR VALVES AND PREPARE BRONZE VALVE BODIES FOR ASSEMBLY. - Stockham Pipe & Fittings Company, Brass Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  7. Magnitude and Timing of Leaf Damage Affect Seed Production in a Natural Population of Arabidopsis thaliana (Brassicaceae)

    PubMed Central

    Akiyama, Reiko; Ågren, Jon

    2012-01-01

    Background The effect of herbivory on plant fitness varies widely. Understanding the causes of this variation is of considerable interest because of its implications for plant population dynamics and trait evolution. We experimentally defoliated the annual herb Arabidopsis thaliana in a natural population in Sweden to test the hypotheses that (a) plant fitness decreases with increasing damage, (b) tolerance to defoliation is lower before flowering than during flowering, and (c) defoliation before flowering reduces number of seeds more strongly than defoliation during flowering, but the opposite is true for effects on seed size. Methodology/Principal Findings In a first experiment, between 0 and 75% of the leaf area was removed in May from plants that flowered or were about to start flowering. In a second experiment, 0, 25%, or 50% of the leaf area was removed from plants on one of two occasions, in mid April when plants were either in the vegetative rosette or bolting stage, or in mid May when plants were flowering. In the first experiment, seed production was negatively related to leaf area removed, and at the highest damage level, also mean seed size was reduced. In the second experiment, removal of 50% of the leaf area reduced seed production by 60% among plants defoliated early in the season at the vegetative rosettes, and by 22% among plants defoliated early in the season at the bolting stage, but did not reduce seed output of plants defoliated one month later. No seasonal shift in the effect of defoliation on seed size was detected. Conclusions/Significance The results show that leaf damage may reduce the fitness of A. thaliana, and suggest that in this population leaf herbivores feeding on plants before flowering should exert stronger selection on defence traits than those feeding on plants during flowering, given similar damage levels. PMID:22276140

  8. EPIDEMIOLOGY OF ALMOND LEAF SCORCH DISEASE IN THE SAN JOAQUIN VALLEY OF CALIFORNIA: FACTORS AFFECTING PATHOGEN DISTRIBUTION AND MOVEMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Almond leaf scorch disease (ALSD) has recently reemerged as a serious threat to almond production areas throughout California’s San Joaquin Valley. This disease, which is caused by the xylem-limited bacterium Xylella fastidiousa, is vectored by xylophagous insects including sharpshooter leafhoppers ...

  9. RNAi-mediated downregulation of poplar plasma membrane intrinsic proteins (PIPs) changes plasma membrane proteome composition and affects leaf physiology.

    PubMed

    Bi, Zhen; Merl-Pham, Juliane; Uehlein, Norbert; Zimmer, Ina; Mühlhans, Stefanie; Aichler, Michaela; Walch, Axel Karl; Kaldenhoff, Ralf; Palme, Klaus; Schnitzler, Jörg-Peter; Block, Katja

    2015-10-14

    Plasma membrane intrinsic proteins (PIPs) are one subfamily of aquaporins that mediate the transmembrane transport of water. To reveal their function in poplar, we generated transgenic poplar plants in which the translation of PIP genes was downregulated by RNA interference investigated these plants with a comprehensive leaf plasma membrane proteome and physiome analysis. First, inhibition of PIP synthesis strongly altered the leaf plasma membrane protein composition. Strikingly, several signaling components and transporters involved in the regulation of stomatal movement were differentially regulated in transgenic poplars. Furthermore, hormonal crosstalk related to abscisic acid, auxin and brassinosteroids was altered, in addition to cell wall biosynthesis/cutinization, the organization of cellular structures and membrane trafficking. A physiological analysis confirmed the proteomic results. The leaves had wider opened stomata and higher net CO2 assimilation and transpiration rates as well as greater mesophyll conductance for CO2 (gm) and leaf hydraulic conductance (Kleaf). Based on these results, we conclude that PIP proteins not only play essential roles in whole leaf water and CO2 flux but have important roles in the regulation of stomatal movement. PMID:26248320

  10. Upper limit for magnetoresistance in silicon bronze and phosphor bronze wire

    NASA Technical Reports Server (NTRS)

    Feldman, R.; Talley, L.; Rojeski, M.; Vold, T.; Woollam, J. A.

    1977-01-01

    The electrical resistivity of silicon bronze and phosphor bronze was measured in magnetic fields from 0 to 14 T and at temperatures between 2 and 300 K. At any fixed temperature, the change in resistivity to 14 T was less than a few parts in 100,000. Thus, these bronzes are excellent for use in high magnetic fields where constant resistance is required. Welding leads to the sample was found to be superior to soldering. The soldered contacts were subject to spurious resistivity changes that resulted from superconducting transitions in the solder.

  11. Scrotal asymmetry, varicocoele and the Riace Bronzes.

    PubMed

    Bonafini, B; Pozzilli, P

    2012-04-01

    In 1972, a pair of remarkably attractive Greek statues, later named Riace Bronzes, were found along the Mediterranean coast in the province of Reggio Calabria, Italy. We analyse the Riace Bronzes in the context of previous research on scrotal asymmetry in Greek statues. By examining their testis, one can define a more exact time of their dating by placing them beside previous observations of scrotal asymmetry, and possibly by taking a pathological condition, varicocoele, as an influencing factor in determining the appearance of the testis. In statue A of the Riace Bronzes, the left testicle is remarkably lower compared with the right one; it also appears as it looks when under physical examination varicocoele is suspected. Being located on the left testicle (as in 90% of cases) and by sight, we feel sufficiently confident to affirm that varicocoele might be diagnosed. PMID:22288773

  12. Crystal chemistry of the natural vanadium bronzes

    USGS Publications Warehouse

    Evans, H.T., Jr.; Hughes, J.M.

    1990-01-01

    The crystal chemistry of the natural vanadium bronze minerals is reviewed on the basis of published information and new studies (mainly by X-ray powder-diffraction methods) using type material wherever possible. The known V bronze minerals are divided into three categories: 1) the hewettite group, 2) the straczekite group, 3) other structure types including navajoite, schubnelite, fervanite, shcherbinaite, bannermanite, and melanovanadite. All known structures associated with the fibrous V bronzes (fiber spacing 3.6 A??) can be considered as various lateral linkages (into sheets or networks) of only two types of polyvanadate chains: 1) a divanadate chain (V2O6)n consisting of alternating square pyramids, and 2) a tetravanadate chain (V4O12)n consisting of four highly condensed single octahedral chains. -from Authors

  13. Clay Corner: Recreating Chinese Bronze Vessels.

    ERIC Educational Resources Information Center

    Gamble, Harriet

    1998-01-01

    Presents a lesson where students make faux Chinese bronze vessels through slab or coil clay construction after they learn about the history, function, and design of these vessels. Utilizes a variety of glaze finishes in order to give the vessels an aged look. Gives detailed guidelines for creating the vessels. (CMK)

  14. Viroid-like RNAs from cherry trees affected by leaf scorch disease: further data supporting their association with mycoviral double-stranded RNAs.

    PubMed

    Minoia, S; Navarro, B; Covelli, L; Barone, M; García-Becedas, M T; Ragozzino, A; Alioto, D; Flores, R; Di Serio, F

    2014-03-01

    Cherry trees from Spain affected by cherry leaf scorch (CLS), a fungal disease proposed to be caused by Apiognomonia erythrostoma, show symptoms (translucent-chlorotic leaf spots evolving into rusty areas) very similar to those of cherry chlorotic rusty spot disease (CCRS) and Amasya cherry disease, reported in Italy and Turkey, respectively. The three maladies are closely associated with 10-12 double-stranded viral RNAs, and CCRS is additionally associated with two cherry small circular RNAs (cscRNA1 and cscRNA2). Here, we report that a small viroid-like RNA similar to the CCRS-associated cscRNA1 is also present in CLS-affected trees, thus extending the link between the two diseases. Both CLS and CCRS cscRNA1 elements have common features, including sequence identity (88%), a predicted quasi rod-like conformation with short bifurcations at both termini, and the presence of hammerhead ribozymes in the strands of both polarities. However, cscRNA2, apparently derived from cscRNA1 by deletion of a short hairpin, was not detected in CLS-affected material. Although the biological nature of cscRNAs is unknown, the identification of at least cscRNA1 in different cherry cultivars and in two distinct geographic areas (Spain and Italy), always in close association with the same mycoviral dsRNAs, supports that these viroid-like RNAs could be satellite RNAs. PMID:24077656

  15. Viroid-like RNAs from cherry trees affected by leaf scorch disease: further data supporting their association with mycoviral double-stranded RNAs.

    PubMed

    Minoia, S; Navarro, B; Covelli, L; Barone, M; García-Becedas, M T; Ragozzino, A; Alioto, D; Flores, R; Di Serio, F

    2014-03-01

    Cherry trees from Spain affected by cherry leaf scorch (CLS), a fungal disease proposed to be caused by Apiognomonia erythrostoma, show symptoms (translucent-chlorotic leaf spots evolving into rusty areas) very similar to those of cherry chlorotic rusty spot disease (CCRS) and Amasya cherry disease, reported in Italy and Turkey, respectively. The three maladies are closely associated with 10-12 double-stranded viral RNAs, and CCRS is additionally associated with two cherry small circular RNAs (cscRNA1 and cscRNA2). Here, we report that a small viroid-like RNA similar to the CCRS-associated cscRNA1 is also present in CLS-affected trees, thus extending the link between the two diseases. Both CLS and CCRS cscRNA1 elements have common features, including sequence identity (88 %), a predicted quasi rod-like conformation with short bifurcations at both termini, and the presence of hammerhead ribozymes in the strands of both polarities. However, cscRNA2, apparently derived from cscRNA1 by deletion of a short hairpin, was not detected in CLS-affected material. Although the biological nature of cscRNAs is unknown, the identification of at least cscRNA1 in different cherry cultivars and in two distinct geographic areas (Spain and Italy), always in close association with the same mycoviral dsRNAs, supports that these viroid-like RNAs could be satellite RNAs. PMID:24757711

  16. The Umm Al Binni Structure and Bronze Age Catastrophes

    NASA Astrophysics Data System (ADS)

    Hamacher, Duane W.

    Archaeological excavations of sites dating from 2200 BCE and 1200 BCE in the Middle East, Asia Minor, and southeast Europe provide evidence that a large scale disaster affected Bronze Age civilizations. There are numerous debates as to whether this was caused by warfare, a large-scale natural disaster, or some other factor. In 2001, Sharad Master used satellite images to discover a possible Holocene impact structure in the Al 'Amarah marshes of southern Iraq, known as Umm al Binni lake. With an estimated age of < 5000 years and a diameter of ~3.4 km, this structure may help explain this disaster. Using numerical models and scaling equations for a cosmic impact, I show that although destructive forces would have damaged Sumerian cities within a few hundred km of the coast, it is unlikely that this single impact would have caused the large-scale destruction seen over the larger region. The impact origin of the structure is unconfirmed and any connection to Bronze Age catastrophes remains speculative. Errata: Table 4 provides a list of impact sites, three of which are associated with nickel-iron impactors and therefore cannot be from a "fragmented comet".

  17. Elevated CO(2) concentration affects leaf photosynthesis-nitrogen relationships in Pinus taeda over nine years in FACE.

    PubMed

    Crous, Kristine Y; Walters, Michael B; Ellsworth, David S

    2008-04-01

    To investigate whether long-term elevated carbon dioxide concentration ([CO(2)]) causes declines in photosynthetic enhancement and leaf nitrogen (N) owing to limited soil fertility, we measured photosynthesis, carboxylation capacity and area-based leaf nitrogen concentration (N(a)) in Pinus taeda L. growing in a long-term free-air CO(2) enrichment (FACE) facility at an N-limited site. We also determined how maximum rates of carboxylation (V(cmax)) and electron transport (J(max)) varied with N(a) under elevated [CO(2)]. In trees exposed to elevated [CO(2)] for 5 to 9 years, the slope of the relationship between leaf photosynthetic capacity (A(net-Ca)) and N(a) was significantly reduced by 37% in 1-year-old needles, whereas it was unaffected in current-year needles. The slope of the relationships of both V(cmax) and J(max) with N(a) decreased in 1-year-old needles after up to 9 years of growth in elevated [CO(2)], which was accompanied by a 15% reduction in N allocation to the carboxylating enzyme. Nitrogen fertilization (110 kg N ha(-1)) in the ninth year of exposure to elevated [CO(2)] restored the slopes of the relationships of V(cmax) and J(max) with N(a) to those of control trees (i.e., in ambient [CO(2)]). The J(max):V(cmax) ratio was unaffected by either [CO(2)] or N fertilization. Changes in the apparent allocation of N to photosynthetic components may be an important adjustment in pines exposed to elevated [CO(2)] on low-fertility sites. We conclude that fundamental relationships between photosynthesis or its component processes with N(a) may be altered in aging pine needles after more than 5 years of exposure to elevated atmospheric [CO(2)]. PMID:18244946

  18. Canopy position affects the relationships between leaf respiration and associated traits in a tropical rainforest in Far North Queensland.

    PubMed

    Weerasinghe, Lasantha K; Creek, Danielle; Crous, Kristine Y; Xiang, Shuang; Liddell, Michael J; Turnbull, Matthew H; Atkin, Owen K

    2014-06-01

    We explored the impact of canopy position on leaf respiration (R) and associated traits in tree and shrub species growing in a lowland tropical rainforest in Far North Queensland, Australia. The range of traits quantified included: leaf R in darkness (RD) and in the light (RL; estimated using the Kok method); the temperature (T)-sensitivity of RD; light-saturated photosynthesis (Asat); leaf dry mass per unit area (LMA); and concentrations of leaf nitrogen (N), phosphorus (P), soluble sugars and starch. We found that LMA, and area-based N, P, sugars and starch concentrations were all higher in sun-exposed/upper canopy leaves, compared with their shaded/lower canopy and deep-shade/understory counterparts; similarly, area-based rates of RD, RL and Asat (at 28 °C) were all higher in the upper canopy leaves, indicating higher metabolic capacity in the upper canopy. The extent to which light inhibited R did not differ significantly between upper and lower canopy leaves, with the overall average inhibition being 32% across both canopy levels. Log-log RD-Asat relationships differed between upper and lower canopy leaves, with upper canopy leaves exhibiting higher rates of RD for a given Asat (both on an area and mass basis), as well as higher mass-based rates of RD for a given [N] and [P]. Over the 25-45 °C range, the T-sensitivity of RD was similar in upper and lower canopy leaves, with both canopy positions exhibiting Q10 values near 2.0 (i.e., doubling for every 10 °C rise in T) and Tmax values near 60 °C (i.e., T where RD reached maximal values). Thus, while rates of RD at 28 °C decreased with increasing depth in the canopy, the T-dependence of RD remained constant; these findings have important implications for vegetation-climate models that seek to predict carbon fluxes between tropical lowland rainforests and the atmosphere. PMID:24722001

  19. Protection of bronze artefacts through polymeric coatings based on nanocarriers filled with corrosion inhibitors

    NASA Astrophysics Data System (ADS)

    de Luna, Martina Salzano; Buonocore, Giovanna; Di Carlo, Gabriella; Giuliani, Chiara; Ingo, Gabriel M.; Lavorgna, Marino

    2016-05-01

    Protective coatings based on polymers synthesized from renewable sources (chitosan or an amorphous vinyl alcohol based polymer) have been prepared for the protection of bronze artifacts from corrosion. Besides acting as an effective barrier against corrosive species present in the environment, the efficiency of the coatings has been improved by adding corrosion inhibitor compounds (benzotriazole or mercaptobenzothiazole) to the formulations. The liquid medium of the formulations has been carefully selected looking at maximizing the wettability on the bronze substrate and optimizing the solvent evaporation rate. The minimum amount of inhibitor compounds has been optimized by performing accelerated corrosion tests on coated bronze substrates. The inhibitors have been directly dissolved in the coating-forming solutions and/or introduced by means of nanocarriers, which allow to control the release kinetics. The free dissolved inhibitor molecules immediately provide a sufficient protection against corrosion. On the other hand, the inhibitor molecules contained in the nanocarriers serve as long-term reservoir, which can be activated by external corrosion-related stimuli in case of particularly severe conditions. Particular attention has been paid to other features which affect the coating performances. Specifically, the adhesion of the protective polymer layer to the bronze substrate has been assessed, as well as its permeability properties and transparency, the latter being a fundamental feature of protective coating for cultural heritages. Finally, the protective efficiency of the produced smart coatings has been assessed through accelerated corrosion tests.

  20. Corrosion investigation of fire-gilded bronze involving high surface resolution spectroscopic imaging

    NASA Astrophysics Data System (ADS)

    Masi, G.; Chiavari, C.; Avila, J.; Esvan, J.; Raffo, S.; Bignozzi, M. C.; Asensio, M. C.; Robbiola, L.; Martini, C.

    2016-03-01

    Gilded bronzes are often affected by severe corrosion, due to defects in the Au layer and Au/Cu alloy galvanic coupling, stimulated by large cathodic area of the gilded layer. Galvanic corrosion, triggered by gilding defects, leads to products growth at the Au/bronze interface, inducing blistering or break-up of the Au layer. In this context, fire-gilded bronze replicas prepared by ancient methods (use of spreadable Au-Hg paste) was specifically characterised by compiling complementary spectroscopic and imaging information before/after accelerated ageing with synthetic rain. Fire-gilded bronze samples were chemically imaged in cross-section at nano-metric scale (<200 nm) using high energy and lateral resolution synchrotron radiation photoemission (HR-SRPES) of core levels and valence band after conventional characterisation of the samples by Glow Discharge optical Emission Spectroscopy (GD-OES) and conventional X-ray photoelectron spectroscopy (XPS). We have found a net surface enrichment in Zn and Sn after fire-gilding and presence of metallic Hg, Pb and Cu within the Au layer. Moreover, the composition distribution of the elements together with their oxidation has been determined. It was also revealed that metallic phases including Hg and Pb remain in the gilding after corrosion. Moreover, selective dissolution of Zn and Cu occurs in the crater due to galvanic coupling, which locally induces relative Sn species enrichment (decuprification). The feasibility advantages and disadvantages of chemical imaging using HR-SRPES to study artworks have been investigated on representative replicas.

  1. PGL, encoding chlorophyllide a oxygenase 1, impacts leaf senescence and indirectly affects grain yield and quality in rice.

    PubMed

    Yang, Yaolong; Xu, Jie; Huang, Lichao; Leng, Yujia; Dai, Liping; Rao, Yuchun; Chen, Long; Wang, Yuqiong; Tu, Zhengjun; Hu, Jiang; Ren, Deyong; Zhang, Guangheng; Zhu, Li; Guo, Longbiao; Qian, Qian; Zeng, Dali

    2016-03-01

    Chlorophyll (Chl) b is a ubiquitous accessory pigment in land plants, green algae, and prochlorophytes. This pigment is synthesized from Chl a by chlorophyllide a oxygenase and plays a key role in adaptation to various environments. This study characterizes a rice mutant, pale green leaf (pgl), and isolates the gene PGL by using a map-based cloning approach. PGL, encoding chlorophyllide a oxygenase 1, is mainly expressed in the chlorenchyma and activated in the light-dependent Chl synthesis process. Compared with wild-type plants, pgl exhibits a lower Chl content with a reduced and disorderly thylakoid ultrastructure, which decreases the photosynthesis rate and results in reduced grain yield and quality. In addition, pgl exhibits premature senescence in both natural and dark-induced conditions and more severe Chl degradation and reactive oxygen species accumulation than does the wild-type. Moreover, pgl is sensitive to heat stress. PMID:26709310

  2. PGL, encoding chlorophyllide a oxygenase 1, impacts leaf senescence and indirectly affects grain yield and quality in rice

    PubMed Central

    Yang, Yaolong; Xu, Jie; Huang, Lichao; Leng, Yujia; Dai, Liping; Rao, Yuchun; Chen, Long; Wang, Yuqiong; Tu, Zhengjun; Hu, Jiang; Ren, Deyong; Zhang, Guangheng; Zhu, Li; Guo, Longbiao; Qian, Qian; Zeng, Dali

    2016-01-01

    Chlorophyll (Chl) b is a ubiquitous accessory pigment in land plants, green algae, and prochlorophytes. This pigment is synthesized from Chl a by chlorophyllide a oxygenase and plays a key role in adaptation to various environments. This study characterizes a rice mutant, pale green leaf (pgl), and isolates the gene PGL by using a map-based cloning approach. PGL, encoding chlorophyllide a oxygenase 1, is mainly expressed in the chlorenchyma and activated in the light-dependent Chl synthesis process. Compared with wild-type plants, pgl exhibits a lower Chl content with a reduced and disorderly thylakoid ultrastructure, which decreases the photosynthesis rate and results in reduced grain yield and quality. In addition, pgl exhibits premature senescence in both natural and dark-induced conditions and more severe Chl degradation and reactive oxygen species accumulation than does the wild-type. Moreover, pgl is sensitive to heat stress. PMID:26709310

  3. Leaf biochemistry of Lycopersicon esculentum Mill. at different stages of plant development as affected by mercury treatment.

    PubMed

    Gauba, Nidhi; Mahmooduzzafar; Siddiqi, T O; Umar, S; Iqbal, Muhammad

    2007-04-01

    The effect of mercury (Hg) on the biochemical parameters of Lycopersicon esculentum Mill leaf was studied. Application of mercuric chloride in varying concentrations (0.5, 1.0, 1.5 and 2.0 mM HgCl2 kg(-1) sand) caused significant reduction that went up to 89% and 72% chlorophyll a and chlorophyll b contents respectively (at flowering stage), 69% in carotenoid content, 64% in total soluble protein content and 91% in nitrate reductase activity (all at post-flowering stage). The amounts of nitrate and proline increased maximally (151% and 143% respectively) at the flowering stage, whereas total soluble sugar enhanced by 57% at the post-flowering stage. Changes observed in most of the parameters, were concentration dependent. Such studies seem to be able to discover suitable bioindicators of heavy metal pollution. PMID:17915770

  4. Hydrothermal synthesis of potassium molybdenum oxide bronzes: structure-inheriting solid-state route to blue bronze and dissolution/deposition route to red bronze

    SciTech Connect

    Eda, Kazuo . E-mail: eda@kobe-u.ac.jp; Chin, Kin; Sotani, Noriyuki; Stanley Whittingham, M.

    2005-01-15

    The hydrothermal syntheses of the alkali metal molybdenum bronzes from starting solids (H{sub x}MoO{sub 3}) with structural affinities to the desired products were investigated. Single-phase potassium blue and red bronzes were prepared by the hydrothermal treatments at around 430K, and characterized by powder X-ray diffraction, IR spectroscopy, and SEM. The formation processes of these two bronzes during the hydrothermal treatments were found to differ. The blue bronze was formed by a structure-inheriting solid-state route from H{sub x}MoO{sub 3} with x<0.3, whereas the red bronze was formed for x>0.3 through a solution dissolution/deposition route via the formation of MoO{sub 3}+MoO{sub 2}.

  5. Knockdown of WHIRLY1 Affects Drought Stress-Induced Leaf Senescence and Histone Modifications of the Senescence-Associated Gene HvS40.

    PubMed

    Janack, Bianka; Sosoi, Paula; Krupinska, Karin; Humbeck, Klaus

    2016-01-01

    The plastid-nucleus located protein WHIRLY1 has been described as an upstream regulator of leaf senescence, binding to the promoter of senescence-associated genes like HvS40. To investigate the impact of WHIRLY1 on drought stress-induced, premature senescence, transgenic barley plants with an RNAi-mediated knockdown of the HvWHIRLY1 gene were grown under normal and drought stress conditions. The course of leaf senescence in these lines was monitored by physiological parameters and studies on the expression of senescence- and drought stress-related genes. Drought treatment accelerated leaf senescence in WT plants, whereas WHIRLY 1 knockdown lines (RNAi-W1) showed a stay-green phenotype. Expression of both senescence-associated and drought stress-responsive genes, was delayed in the transgenic plants. Notably, expression of transcription factors of the WRKY and NAC families, which are known to function in senescence- and stress-related signaling pathways, was affected in plants with impaired accumulation of WHIRLY1, indicating that WHIRLY1 acts as an upstream regulator of drought stress-induced senescence. To reveal the epigenetic indexing of HvS40 at the onset of drought-induced senescence in WT and RNAi-W1 lines, stress-responsive loading with histone modifications of promoter and coding sequences of HvS40 was analyzed by chromatin immunoprecipitation and quantified by qRT-PCR. In the wildtype, the euchromatic mark H3K9ac of the HvS40 gene was low under control conditions and was established in response to drought treatment, indicating the action of epigenetic mechanisms in response to drought stress. However, drought stress caused no significant increase in H3K9ac in plants impaired in accumulation of WHIRLY1. The results show that WHIRLY1 knockdown sets in motion a delay in senescence that involves all aspects of gene expression, including changes in chromatin structure. PMID:27608048

  6. Proteins associated with heat-induced leaf senescence in creeping bentgrass as affected by foliar application of nitrogen, cytokinins, and an ethylene inhibitor.

    PubMed

    Jespersen, David; Huang, Bingru

    2015-02-01

    Heat stress causes premature leaf senescence in cool-season grass species. The objective of this study was to identify proteins regulated by nitrogen, cytokinins, and ethylene inhibitor in relation to heat-induced leaf senescence in creeping bentgrass (Agrostis stolonifera). Plants (cv. Penncross) were foliar sprayed with 18 mM carbonyldiamide (N source), 25 μM aminoethoxyvinylglycine (AVG, ethylene inhibitor), 25 μM zeatin riboside (ZR, cytokinin), or a water control, and then exposed to 20/15°C (day/night) or 35/30°C (heat stress) in growth chambers. All treatments suppressed heat-induced leaf senescence, as shown by higher turf quality and chlorophyll content, and lower electrolyte leakage in treated plants compared to the untreated control. A total of 49 proteins were responsive to N, AVG, or ZR under heat stress. The abundance of proteins in photosynthesis increased, with ribulose-1,5-bisphosphate carboxylase/oxygenase affected by all three treatments, chlorophyll a/b-binding protein by AVG and N or Rubisco activase by AVG. Proteins for amino acid metabolism were upregulated, including alanine aminotransferase by three treatments and ferredoxin-dependent glutamate synthase by AVG and N. Upregulated proteins also included catalase by AVG and N and heat shock protein by ZR. Exogenous applications of AVG, ZR, or N downregulated proteins in respiration (enolase, glyceraldehyde 3-phosphate dehydrogenase, and succinate dehygrogenase) under heat stress. Alleviation of heat-induced senescence by N, AVG, or ZR was associated with enhanced protein abundance in photosynthesis and amino acid metabolism and stress defense systems (heat shock protection and antioxidants), as well as suppression of those imparting respiration metabolism. PMID:25407697

  7. Microstructure and wear property of spray formed high leaded bronze

    NASA Astrophysics Data System (ADS)

    Yan, Pengfei; Wang, Deping; Yan, Biao

    2015-03-01

    In this research, Cu-9Pb high leaded bronze were prepared by spray forming. The microstructure and wear properties of this bronze alloy were systematically investigated. The results show that although the hardness of spray formed alloy was not increased comparing with the cast alloy, it still presented a lower wear rate and a lower friction coefficient in dry sliding wear tests as shallower grooves and more lubricating films were observed in the spray formed bronze (BSF14). Spray forming also refined the lead phase microstructure of Cu-9Pb bronze and improved its wear properties.

  8. Enzymatic activities in different strains isolated from healthy and brittle leaf disease affected date palm leaves: study of amylase production conditions.

    PubMed

    Mouna, Jrad; Imen, Fendri; Choba Ines, Ben; Nourredine, Drira; Adel, Kadri; Néji, Gharsallah

    2015-02-01

    The present study aimed to investigate and compare the enzymatic production of endophytic bacteria isolated from healthy and brittle leaf disease affected date palm leaves (pectinase, cellulase, lipase, and amylase). The findings revealed that the enzymatic products from the bacterial isolates of healthy date palm leaves were primarily 33% amylolytic enzyme, 33 % cellulase, 25 % pectinase, and 25 % lipase. The isolates from brittle leaf disease date palm leaves, on the other hand, were noted to produce 16 % amylolytic enzyme, 20 % cellulose, 50 % pectinase, and 50 % lipase. The effects of temperature and pH on amylase, pectinase, and cellulose activities were investigated. The Bacillus subtilis JN934392 strain isolated from healthy date palm leaves produced higher levels of amylase activity at pH 7. A Box Behnken Design (BBD) was employed to optimize amylase extraction. Maximal activity was observed at pH and temperature ranges of pH 6-6.5 and 37-39 °C, respectively. Under those conditions, amylase activity was noted to be attained 9.37 U/ml. The results showed that the enzyme was able to maintain more than 50 % of its activity over a temperature range of 50-80 °C, with an optimum at 70 °C. This bacterial amylase showed high activity compared to other bacteria, which provides support for its promising candidacy for future industrial application. PMID:25432343

  9. Transmission of Tomato Yellow Leaf Curl Virus by Bemisia tabaci as Affected by Whitefly Sex and Biotype

    PubMed Central

    Ning, Wenxi; Shi, Xiaobin; Liu, Baiming; Pan, Huipeng; Wei, Wanting; Zeng, Yang; Sun, Xinpei; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Cheng, Jiaxu; Peng, Zhengke; Zhang, Youjun

    2015-01-01

    Bemisia tabaci is a serious pest of vegetables and other crops worldwide. The most damaging and predominant B. tabaci biotypes are B and Q, and both are vectors of tomato yellow leaf curl virus (TYLCV). Previous research has shown that Q outperforms B in many respects but comparative research is lacking on the ability of B and Q to transmit viruses. In the present study, we tested the hypothesis that B and Q differ in their ability to transmit TYLCV and that this difference helps explain TYLCV outbreaks. We compared the acquisition, retention, and transmission of TYLCV by B and Q females and males. We found that Q females are more efficient than Q males, B females, and B males at TYLCV acquisition and transmission. Although TYLCV acquisition and transmission tended to be greater for B females than B males, the differences were not statistically significant. Based on electrical penetration graphs determination of phloem sap ingestion parameters, females fed better than males, and Q females fed better than Q males, B females, or B males. These results are consistent with the occurrences of TYLCV outbreaks in China, which have been associated with the spread of Q rather than B. PMID:26021483

  10. Transmission of Tomato Yellow Leaf Curl Virus by Bemisia tabaci as Affected by Whitefly Sex and Biotype.

    PubMed

    Ning, Wenxi; Shi, Xiaobin; Liu, Baiming; Pan, Huipeng; Wei, Wanting; Zeng, Yang; Sun, Xinpei; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Cheng, Jiaxu; Peng, Zhengke; Zhang, Youjun

    2015-01-01

    Bemisia tabaci is a serious pest of vegetables and other crops worldwide. The most damaging and predominant B. tabaci biotypes are B and Q, and both are vectors of tomato yellow leaf curl virus (TYLCV). Previous research has shown that Q outperforms B in many respects but comparative research is lacking on the ability of B and Q to transmit viruses. In the present study, we tested the hypothesis that B and Q differ in their ability to transmit TYLCV and that this difference helps explain TYLCV outbreaks. We compared the acquisition, retention, and transmission of TYLCV by B and Q females and males. We found that Q females are more efficient than Q males, B females, and B males at TYLCV acquisition and transmission. Although TYLCV acquisition and transmission tended to be greater for B females than B males, the differences were not statistically significant. Based on electrical penetration graphs determination of phloem sap ingestion parameters, females fed better than males, and Q females fed better than Q males, B females, or B males. These results are consistent with the occurrences of TYLCV outbreaks in China, which have been associated with the spread of Q rather than B. PMID:26021483

  11. Solanum tuberosum and Lycopersicon esculentum Leaf Extracts and Single Metabolites Affect Development and Reproduction of Drosophila melanogaster

    PubMed Central

    Ventrella, Emanuela; Adamski, Zbigniew; Chudzińska, Ewa; Miądowicz-Kobielska, Mariola; Marciniak, Paweł; Büyükgüzel, Ender; Büyükgüzel, Kemal; Erdem, Meltem; Falabella, Patrizia; Scrano, Laura; Bufo, Sabino Aurelio

    2016-01-01

    Glycoalkaloids are secondary metabolites commonly found in Solanaceae plants. They have anti-bacterial, anti-fungal and insecticidal activities. In the present study we examine the effects of potato and tomato leaf extracts and their main components, the glycoalkaloids α-solanine, α-chaconine and α-tomatine, on development and reproduction of Drosophila melanogaster wild-type flies at different stages. Parental generation was exposed to five different concentrations of tested substances. The effects were examined also on the next, non-exposed generation. In the first (exposed) generation, addition of each extract reduced the number of organisms reaching the pupal and imaginal stages. Parent insects exposed to extracts and metabolites individually applied showed faster development. However, the effect was weaker in case of single metabolites than in case of exposure to extracts. An increase of developmental rate was also observed in the next, non-exposed generation. The imagoes of both generations exposed to extracts and pure metabolites showed some anomalies in body size and malformations, such as deformed wings and abdomens, smaller black abdominal zone. Our results further support the current idea that Solanaceae can be an impressive source of molecules, which could efficaciously be used in crop protection, as natural extract or in formulation of single pure metabolites in sustainable agriculture. PMID:27213896

  12. Rosmarinus officinalis L. leaf extract improves memory impairment and affects acetylcholinesterase and butyrylcholinesterase activities in rat brain.

    PubMed

    Ozarowski, Marcin; Mikolajczak, Przemyslaw L; Bogacz, Anna; Gryszczynska, Agnieszka; Kujawska, Malgorzata; Jodynis-Liebert, Jadwiga; Piasecka, Anna; Napieczynska, Hanna; Szulc, Michał; Kujawski, Radoslaw; Bartkowiak-Wieczorek, Joanna; Cichocka, Joanna; Bobkiewicz-Kozlowska, Teresa; Czerny, Boguslaw; Mrozikiewicz, Przemyslaw M

    2013-12-01

    Rosmarinus officinalis L. leaf as part of a diet and medication can be a valuable proposal for the prevention and treatment of dementia. The aim of the study was to assess the effects of subchronic (28-fold) administration of a plant extract (RE) (200 mg/kg, p.o.) on behavioral and cognitive responses of rats linked with acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activity and their mRNA expression level in the hippocampus and frontal cortex. The passive avoidance test results showed that RE improved long-term memory in scopolamine-induced rats. The extract inhibited the AChE activity and showed a stimulatory effect on BuChE in both parts of rat brain. Moreover, RE produced a lower mRNA BuChE expression in the cortex and simultaneously an increase in the hippocampus. The study suggests that RE led to improved long-term memory in rats, which can be partially explained by its inhibition of AChE activity in rat brain. PMID:24080468

  13. Solanum tuberosum and Lycopersicon esculentum Leaf Extracts and Single Metabolites Affect Development and Reproduction of Drosophila melanogaster.

    PubMed

    Ventrella, Emanuela; Adamski, Zbigniew; Chudzińska, Ewa; Miądowicz-Kobielska, Mariola; Marciniak, Paweł; Büyükgüzel, Ender; Büyükgüzel, Kemal; Erdem, Meltem; Falabella, Patrizia; Scrano, Laura; Bufo, Sabino Aurelio

    2016-01-01

    Glycoalkaloids are secondary metabolites commonly found in Solanaceae plants. They have anti-bacterial, anti-fungal and insecticidal activities. In the present study we examine the effects of potato and tomato leaf extracts and their main components, the glycoalkaloids α-solanine, α-chaconine and α-tomatine, on development and reproduction of Drosophila melanogaster wild-type flies at different stages. Parental generation was exposed to five different concentrations of tested substances. The effects were examined also on the next, non-exposed generation. In the first (exposed) generation, addition of each extract reduced the number of organisms reaching the pupal and imaginal stages. Parent insects exposed to extracts and metabolites individually applied showed faster development. However, the effect was weaker in case of single metabolites than in case of exposure to extracts. An increase of developmental rate was also observed in the next, non-exposed generation. The imagoes of both generations exposed to extracts and pure metabolites showed some anomalies in body size and malformations, such as deformed wings and abdomens, smaller black abdominal zone. Our results further support the current idea that Solanaceae can be an impressive source of molecules, which could efficaciously be used in crop protection, as natural extract or in formulation of single pure metabolites in sustainable agriculture. PMID:27213896

  14. Factors affecting population dynamics of leaf beetles in a subarctic region: The interplay between climate warming and pollution decline.

    PubMed

    Zvereva, Elena L; Hunter, Mark D; Zverev, Vitali; Kozlov, Mikhail V

    2016-10-01

    Understanding the mechanisms by which abiotic drivers, such as climate and pollution, influence population dynamics of animals is important for our ability to predict the population trajectories of individual species under different global change scenarios. We monitored four leaf beetle species (Coleoptera: Chrysomelidae) feeding on willows (Salix spp.) in 13 sites along a pollution gradient in subarctic forests of north-western Russia from 1993 to 2014. During a subset of years, we also measured the impacts of natural enemies and host plant quality on the performance of one of these species, Chrysomela lapponica. Spring and fall temperatures increased by 2.5-3°C during the 21-year observation period, while emissions of sulfur dioxide and heavy metals from the nickel-copper smelter at Monchegorsk decreased fivefold. However, contrary to predictions of increasing herbivory with climate warming, and in spite of discovered increase in host plant quality with increase in temperatures, none of the beetle species became more abundant during the past 20years. No directional trends were observed in densities of either Phratora vitellinae or Plagiodera versicolora, whereas densities of both C. lapponica and Gonioctena pallida showed a simultaneous rapid 20-fold decline in the early 2000s, remaining at very low levels thereafter. Time series analysis and model selection indicated that these abrupt population declines were associated with decreases in aerial emissions from the smelter. Observed declines in the population densities of C. lapponica can be explained by increases in mortality from natural enemies due to the combined action of climate warming and declining pollution. This pattern suggests that at least in some tri-trophic systems, top-down factors override bottom-up effects and govern the impacts of environmental changes on insect herbivores. PMID:27266523

  15. Thermal and Electrical Conductivity Measurements of CDA 510 Phosphor Bronze

    NASA Technical Reports Server (NTRS)

    Tuttle, James E.; Canavan, Edgar; DiPirro, Michael

    2009-01-01

    Many cryogenic systems use electrical cables containing phosphor bronze wire. While phosphor bronze's electrical and thermal conductivity values have been published, there is significant variation among different phosphor bronze formulations. The James Webb Space Telescope (JWST) will use several phosphor bronze wire harnesses containing a specific formulation (CDA 510, annealed temper). The heat conducted into the JWST instrument stage is dominated by these harnesses, and approximately half of the harness conductance is due to the phosphor bronze wires. Since the JWST radiators are expected to just keep the instruments at their operating temperature with limited cooling margin, it is important to know the thermal conductivity of the actual alloy being used. We describe an experiment which measured the electrical and thermal conductivity of this material between 4 and 295 Kelvin.

  16. 77 FR 14600 - Pricing for 2012 Kennedy Half-Dollar Bags and Rolls, Bronze Medals, the First Spouse Bronze Medal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-12

    ... United States Mint Pricing for 2012 Kennedy Half-Dollar Bags and Rolls, Bronze Medals, the First Spouse Bronze Medal Set and the Birth Set AGENCY: United States Mint, Department of the Treasury. ACTION: Notice. SUMMARY: The United States Mint is announcing 2012 pricing for Kennedy Half-Dollar bags and rolls,...

  17. [Sound duration and sound pattern affect the recovery cycles of inferior collicular neurons in leaf-nosed bat, Hipposideros armiger].

    PubMed

    Tang, Jia; Fu, Zi-Ying; Wu, Fei-Jian

    2010-10-25

    The effects of sound duration and sound pattern on the recovery cycles of inferior collicular (IC) neurons in constant frequency-frequency modulation (CF-FM) bats were explored in this study. Five leaf-nosed bats, Hipposideros armiger (4 males, 1 female, 43-50 g body weight), were used as subjects. The extracellular responses of IC neurons to paired sound stimuli with different duration and patterns were recorded, and the recovery was counted as the ratio of the second response to the first response. Totally, 169 sound-sensitive IC neurons were recorded in the experiment. According to the interpulse interval (IPI) of paired sounds when neurons reached 50% recovery (50% IPI), the recovery cycles of these IC neurons were classified into 3 types: fast recovery (F, the 50% IPI was less than 15 ms), short recovery (S, the 50% IPI was between 15.1 and 30 ms) and long recovery (L, the 50% IPI was more than 30 ms). When paired CF stimuli with 2 ms duration was used, the ratio of F neurons was 32.3%, and it decreased to 18.1% and 18.2% respectively when 5 and 7 ms CF stimuli were used. The ratios of S and L neurons were 41.5%, 33.7%, 29.1% and 26.2%, 48.2%, 52.7% respectively when 2, 5 and 7 ms CF stimuli were used. The average 50% IPI determined after stimulation with paired 2 ms, 5 ms and 7 ms CF sounds were (30.2 ± 27.6), (39.9 ± 29.1) and (49.4 ± 34.7) ms, respectively, and the difference among them was significant (P< 0.01). When the stimuli of paired 2 ms CF sounds were shifted to paired 2 ms FM sounds, the proportion of F, S and L neurons changed from 32.3%, 41.5%, 26.2% to 47.7%, 24.6%, 27.7%, respectively, and the average 50% IPI decreased from (30.2 ± 27.6) to (23.9 ± 19.0) ms (P< 0.05, n = 65). When paired 5+2 ms CF-FM pulses were used instead of 7 ms CF sounds, the proportion of F, S and L neurons changed from 18.2%, 29.1%, 52.7% to 29.1%, 27.3%, 43.6%, respectively, and the average 50% IPI decreased from (49.4 ± 34.7) to (36.3 ± 29.4) ms (P< 0.05, n = 55

  18. Waterlogging in late dormancy and the early growth phase affected root and leaf morphology in Betula pendula and Betula pubescens seedlings.

    PubMed

    Wang, Ai-Fang; Roitto, Marja; Sutinen, Sirkka; Lehto, Tarja; Heinonen, Jaakko; Zhang, Gang; Repo, Tapani

    2016-01-01

    The warmer winters of the future will increase snow-melt frequency and rainfall, thereby increasing the risk of soil waterlogging and its effects on trees in winter and spring at northern latitudes. We studied the morphology of roots and leaves of 1-year-old silver birch (Betula pendula Roth) and pubescent birch (Betula pubescens Ehrh.) seedlings exposed to waterlogging during dormancy or at the beginning of the growing season in a growth-chamber experiment. The experiment included 4-week dormancy (Weeks 1-4), a 4-week early growing season (Weeks 5-8) and a 4-week late growing season (Weeks 9-12). The treatments were: (i) no waterlogging, throughout the experiment ('NW'); (ii) 4-week waterlogging during dormancy (dormancy waterlogging 'DW'); (iii) 4-week waterlogging during the early growing season (growth waterlogging 'GW'); and (iv) 4-week DW followed by 4-week GW during the early growing season ('DWGW'). Dormancy waterlogging affected the roots of silver birch and GW the roots and leaf characteristics of both species. Leaf area was reduced in both species by GW and DWGW. In pubescent birch, temporarily increased formation of thin roots was seen in root systems of GW seedlings, which suggests an adaptive mechanism with respect to excess soil water. Additionally, the high density of non-glandular trichomes and their increase in DWGW leaves were considered possible morphological adaptations to excess water in the soil, as was the constant density of stem lenticels during stem-diameter growth. The higher density in glandular trichomes of DWGW silver birch suggests morphological acclimation in that species. The naturally low density of non-glandular trichomes, low density of stem lenticels in waterlogged seedlings and decrease in root growth seen in DWGW and DW silver birch seedlings explain, at least partly, why silver birch grows more poorly relative to pubescent birch in wet soils. PMID:26420790

  19. Summer (subarctic) versus winter (subtropic) production affects spinach (Spinacia oleracea L.) leaf bionutrients: vitamins (C, E, Folate, K1, provitamin A), lutein, phenolics, and antioxidants.

    PubMed

    Lester, Gene E; Makus, Donald J; Hodges, D Mark; Jifon, John L

    2013-07-24

    Comparison of spinach (Spinacia oleracea L.) cultivars Lazio and Samish grown during the summer solstice in the subarctic versus the winter solstice in the subtropics provided insight into interactions between production environment (light intensity), cultivar, and leaf age/maturity/position affecting bionutrient concentrations of vitamins (C, E, folate, K1, provitamin A), lutein, phenolics, and antioxidants. Growing spinach during the winter solstice in the subtropics resulted in increased leaf dry matter %, oxidized (dehydro) ascorbic acid (AsA), α- and γ-tocopherol, and total phenols but lower reduced (free) AsA, α-carotene, folate, and antioxidant capacity compared to summer solstice-grown spinach in the subarctic. Both cultivars had similar bionutrients, except for higher dehydroAsA, and lower α- and γ-tocopherol in 'Samish' compared to 'Lazio'. For most bionutrients measured, there was a linear, and sometimes quadratic, increase in concentrations from bottom to top canopy leaves. However, total phenolics and antioxidant capacity increased basipetally. The current study has thus demonstrated that dehydroAsA, α-tocopherol, and γ-tocopherol were substantially lower in subarctic compared to subtropical-grown spinach, whereas the opposite relationship was found for antioxidant capacity, α-carotene, and folates (vitamin B9). The observations are consistent with previously reported isolated effects of growth environment on bionutrient status of crops. The current results clearly highlight the effect of production environment (predominantly radiation capture), interacting with genetics and plant phenology to alter the bionutrient status of crops. While reflecting the effects of changing growing conditions, these results also indicate potential alterations in the nutritive value of foods with anticipated shifts in global climatic conditions. PMID:23834651

  20. Endocarp thickness affects seed removal speed by small rodents in a warm-temperate broad-leafed deciduous forest, China

    NASA Astrophysics Data System (ADS)

    Zhang, Hongmao; Zhang, Zhibin

    2008-11-01

    Seed traits are important factors affecting seed predation by rodents and thereby the success of recruitment. Seeds of many tree species have hard hulls. These are thought to confer mechanical protection, but the effect of endocarp thickness on seed predation by rodents has not been well investigated. Wild apricot ( Prunus armeniaca), wild peach ( Amygdalus davidiana), cultivated walnut ( Juglans regia), wild walnut ( Juglans mandshurica Maxim) and Liaodong oak ( Quercus liaotungensis) are very common tree species in northwestern Beijing city, China. Their seeds vary greatly in size, endocarp thickness, caloric value and tannin content. This paper aims to study the effects of seed traits on seed removal speed of these five tree species by small rodents in a temperate deciduous forest, with emphasis on the effect of endocarp thickness. The results indicated that speed of removal of seeds released at stations in the field decreased significantly with increasing endocarp thickness. We found no significant correlations between seed removal speed and other seed traits such as seed size, caloric value and tannin content. In seed selection experiments in small cages, Père David's rock squirrel ( Sciurotamias davidianus), a large-bodied, strong-jawed rodent, selected all of the five seed species, and the selection order among the five seed species was determined by endocarp thickness and the ratio of endocarp mass/seed mass. In contrast, the Korean field mouse ( Apodemus peninsulae) and Chinese white-bellied rat ( Niviventer confucianus), with relatively small bodies and weak jaws, preferred to select small seeds like acorns of Q. liaotungensis and seeds of P. armeniaca, indicating that rodent body size is also an important factor affecting food selection based on seed size. These results suggest endocarp thickness significantly reduces seed removal speed by rodents and then negatively affects dispersal fitness of seeds before seed removal of tree species in the study

  1. Silencing of the tomato sugar partitioning affecting protein (SPA) modifies sink strength through a shift in leaf sugar metabolism.

    PubMed

    Bermúdez, Luisa; de Godoy, Fabiana; Baldet, Pierre; Demarco, Diego; Osorio, Sonia; Quadrana, Leandro; Almeida, Juliana; Asis, Ramón; Gibon, Yves; Fernie, Alisdair R; Rossi, Magdalena; Carrari, Fernando

    2014-03-01

    Limitations in our understanding about the mechanisms that underlie source-sink assimilate partitioning are increasingly becoming a major hurdle for crop yield enhancement via metabolic engineering. By means of a comprehensive approach, this work reports the functional characterization of a DnaJ chaperone related-protein (named as SPA; sugar partition-affecting) that is involved in assimilate partitioning in tomato plants. SPA protein was found to be targeted to the chloroplast thylakoid membranes. SPA-RNAi tomato plants produced more and heavier fruits compared with controls, thus resulting in a considerable increment in harvest index. The transgenic plants also displayed increased pigment levels and reduced sucrose, glucose and fructose contents in leaves. Detailed metabolic and enzymatic activities analyses showed that sugar phosphate intermediates were increased while the activity of phosphoglucomutase, sugar kinases and invertases was reduced in the photosynthetic organs of the silenced plants. These changes would be anticipated to promote carbon export from foliar tissues. The combined results suggested that the tomato SPA protein plays an important role in plastid metabolism and mediates the source-sink relationships by affecting the rate of carbon translocation to fruits. PMID:24372694

  2. Acclimations to light quality on plant and leaf level affect the vulnerability of pepper (Capsicum annuum L.) to water deficit.

    PubMed

    Hoffmann, Anna M; Noga, Georg; Hunsche, Mauricio

    2015-03-01

    We investigated the influence of light quality on the vulnerability of pepper plants to water deficit. For this purpose plants were cultivated either under compact fluorescence lamps (CFL) or light-emitting diodes (LED) providing similar photon fluence rates (95 µmol m(-2) s(-1)) but distinct light quality. CFL emit a wide-band spectrum with dominant peaks in the green and red spectral region, whereas LEDs offer narrow band spectra with dominant peaks at blue (445 nm) and red (665 nm) regions. After one-week acclimation to light conditions plants were exposed to water deficit by withholding irrigation; this period was followed by a one-week regeneration period and a second water deficit cycle. In general, plants grown under CFL suffered more from water deficit than plants grown under LED modules, as indicated by the impairment of the photosynthetic efficiency of PSII, resulting in less biomass accumulation compared to respective control plants. As affected by water shortage, plants grown under CFL had a stronger decrease in the electron transport rate (ETR) and more pronounced increase in heat dissipation (NPQ). The higher amount of blue light suppressed plant growth and biomass formation, and consequently reduced the water demand of plants grown under LEDs. Moreover, pepper plants exposed to high blue light underwent adjustments at chloroplast level (e.g., higher Chl a/Chl b ratio), increasing the photosynthetic performance under the LED spectrum. Differently than expected, stomatal conductance was comparable for water-deficit and control plants in both light conditions during the stress and recovery phases, indicating only minor adjustments at the stomatal level. Our results highlight the potential of the target-use of light quality to induce structural and functional acclimations improving plant performance under stress situations. PMID:25626402

  3. Investigation on a "tentacle-like" corrosion feature on Bronze Age tin-bronze objects

    NASA Astrophysics Data System (ADS)

    Piccardo, Paolo; Mödlinger, Marianne; Ghiara, Giorgia; Campodonico, Serena; Bongiorno, Valeria

    2013-12-01

    Studying the micro-structure of Austrian, Bosnian and Croatian Bronze Age objects made of tin bronze, a rare kind of corrosion feature, called in the following "tentacle-like" according to its specific way of penetrating the metallic matrix, was noted and investigated. Differing from the more classical intergranular, pitting, or crevice corrosion features, the "tentacle-like" corrosion is not following the grain boundaries, nor precisely positioned under the etching area, but penetrates mainly the crystal matrix without any apparent order. This paper discusses the first results achieved and the following hypotheses formulated in respect of the typology of this corrosion. The analyses were carried out by optical microscopy, Raman microspectroscopy, and scanning electron microscopy equipped with EDX spectroscopy for quantitative analyses.

  4. VIEW TO THE SOUTHEAST. MEMORIAL WITH BRONZE PLAQUE IN HONOR ...

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

    VIEW TO THE SOUTHEAST. MEMORIAL WITH BRONZE PLAQUE IN HONOR OF KELLER, MARKS THE CENTER OF THE BRIDGE. - Keller Memorial Bridge, Spanning Tennessee River at U.S. Highway 31, Decatur, Morgan County, AL

  5. 52. photocopy of bronze eagle which later was mounted on ...

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

    52. photocopy of bronze eagle which later was mounted on Tower. Photograph taken at Tacony Iron and Metal Co. works, c. 1892. PCA - The New Public Buildings, Penn Square, Broad & Market Streets, Philadelphia, Philadelphia County, PA

  6. Detail of bronze door on south side of unused section ...

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

    Detail of bronze door on south side of unused section of main lobby. Door accessed stairway leading to Federal Street entrance - Stamford Post Office, 421 Atlantic Street, Stamford, Fairfield County, CT

  7. Limestone and bronze "Mississippi River Crossing" Bridge plaque located at ...

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

    Limestone and bronze "Mississippi River Crossing" Bridge plaque located at North corner of Administration Building site - Huey P. Long Bridge, Administration Building, 5100 Jefferson Highway, Jefferson, Jefferson Parish, LA

  8. Detail view of the bronze gates, lit from behind by ...

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

    Detail view of the bronze gates, lit from behind by the sun - United States Department of Commerce, Bounded by Fourteenth, Fifteenth, and E streets and Constitution Avenue, Washington, District of Columbia, DC

  9. 45. VIEW OF BRONZE BUILDERS PLATE LOCATED ON NORTH SIDE ...

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

    45. VIEW OF BRONZE BUILDERS PLATE LOCATED ON NORTH SIDE AT OUTERMOST END OF WESTERN APPROACH WALL - Tomlinson Bridge, Spanning Quinnipiac River at Forbes Street (U.S. Route 1), New Haven, New Haven County, CT

  10. 25. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, LOBBY, DETAIL OF BRONZE ...

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

    25. INTERIOR, FIRST FLOOR, SOUTH ENTRANCE, LOBBY, DETAIL OF BRONZE AND GLASS DOORS (4' x 5' negative; 8' x 10' print) - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  11. 18. Photocopy of drawing of bronze dedication plaque, circa 1903 ...

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

    18. Photocopy of drawing of bronze dedication plaque, circa 1903 (original drawing in possession of City Engineer's Office Grand Rapids, Michigan) DEDICATION PLAQUE. - Bridge Street Bridge, Spanning Grand River, Michigan & Bridge Streets, Grand Rapids, MI

  12. 30. Bronze plaque located on southern inner wall at east ...

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

    30. Bronze plaque located on southern inner wall at east end of south pier taken looking southeast - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  13. Interior view, detail to show the ornate bronze doors to ...

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

    Interior view, detail to show the ornate bronze doors to the entrance lobby elevators - United States Department of Commerce, Bounded by Fourteenth, Fifteenth, and E streets and Constitution Avenue, Washington, District of Columbia, DC

  14. 9. Bronze slide expansion plate at Pier 3, on right, ...

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

    9. Bronze slide expansion plate at Pier 3, on right, fixed end left. - Monongahela Connecting Railroad Company, Hot Metal Bridge, Spanning Monongahela River at mile post 3.1, Pittsburgh, Allegheny County, PA

  15. Detail view of bronze door. Note oak branches with acorns ...

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

    Detail view of bronze door. Note oak branches with acorns in the left panels and olive branches with olives in right. - Flanders Field American Cemetery & Memorial, Chapel, Wortegemseweg 117, Waregem, West Flanders (Belgium)

  16. 12. DETAIL VIEW OF CIRCULAR BRONZE ROLLER GATE POSITION GAUGE, ...

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

    12. DETAIL VIEW OF CIRCULAR BRONZE ROLLER GATE POSITION GAUGE, ROLLER GATE PIER HOUSE, TYPE 2A, DAM - Mississippi River 9-Foot Channel Project, Lock & Dam No. 11, Upper Mississippi River, Dubuque, Dubuque County, IA

  17. 14. DETAIL VIEW OF BRONZE ROLLER GATE GAUGE, LOOKING SOUTHEAST ...

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

    14. DETAIL VIEW OF BRONZE ROLLER GATE GAUGE, LOOKING SOUTHEAST INSIDE ROLLER GATE OPERATING MACHINERY HOUSE - Upper Mississippi River Nine-Foot Channel Project, Lock & Dam No. 25, Cap au Gris, Lincoln County, MO

  18. Preparation and evaluation of thin-film sodium tungsten bronzes

    NASA Technical Reports Server (NTRS)

    Kautz, H. E.; Fielder, W. L.; Singer, J.; Fordyce, J. S.

    1974-01-01

    Thin films of sodium tungsten bronze (NaxWO3) were investigated as reversible sodium ion electrodes for solid electrolytes. The films were made by electron beam evaporation of the three phases, W metal, Na2WO4, and WO3, followed by sintering. The substrates were sodium beta alumina disks and glass slides. X-ray diffraction analyses of the films showed that sintering in dry nitrogen with prior exposure to air lead to mixed phases. Sintering in vacuum with no air exposure produced tetragonal I bronze with a nominal composition of Na0.31WO3, single phase within the limits of X-ray diffraction detectability. The films were uniform and adherent on sodium beta alumina substrates. The ac and dc conductivities of the beta alumina were measured with the sodium tungsten bronze films as electrodes. These experiments indicated that the tetragonal I bronze electrodes were not completely reversible. This may have resulted from sodium ion blocking within the bronze film or at the bronze beta alumina interface. Methods for attempting to make more completely reversible electrodes are suggested.

  19. The Decreased apical dominance1/Petunia hybrida CAROTENOID CLEAVAGE DIOXYGENASE8 Gene Affects Branch Production and Plays a Role in Leaf Senescence, Root Growth, and Flower Development

    PubMed Central

    Snowden, Kimberley C.; Simkin, Andrew J.; Janssen, Bart J.; Templeton, Kerry R.; Loucas, Holly M.; Simons, Joanne L.; Karunairetnam, Sakuntala; Gleave, Andrew P.; Clark, David G.; Klee, Harry J.

    2005-01-01

    Carotenoids and carotenoid cleavage products play an important and integral role in plant development. The Decreased apical dominance1 (Dad1)/PhCCD8 gene of petunia (Petunia hybrida) encodes a hypothetical carotenoid cleavage dioxygenase (CCD) and ortholog of the MORE AXILLARY GROWTH4 (MAX4)/AtCCD8 gene. The dad1-1 mutant allele was inactivated by insertion of an unusual transposon (Dad-one transposon), and the dad1-3 allele is a revertant allele of dad1-1. Consistent with its role in producing a graft-transmissible compound that can alter branching, the Dad1/PhCCD8 gene is expressed in root and shoot tissue. This expression is upregulated in the stems of the dad1-1, dad2, and dad3 increased branching mutants, indicating feedback regulation of the gene in this tissue. However, this feedback regulation does not affect the root expression of Dad1/PhCCD8. Overexpression of Dad1/PhCCD8 in the dad1-1 mutant complemented the mutant phenotype, and RNA interference in the wild type resulted in an increased branching phenotype. Other differences in phenotype associated with the loss of Dad1/PhCCD8 function included altered timing of axillary meristem development, delayed leaf senescence, smaller flowers, reduced internode length, and reduced root growth. These data indicate that the substrate(s) and/or product(s) of the Dad1/PhCCD8 enzyme are mobile signal molecules with diverse roles in plant development. PMID:15705953

  20. The effect of uric acid on outdoor copper and bronze.

    PubMed

    Bernardi, E; Bowden, D J; Brimblecombe, P; Kenneally, H; Morselli, L

    2009-03-15

    Bird droppings are often quoted as a decay agent for outdoor goods, in particular buildings and statues. Undoubtedly, they represent one of the major causes of aesthetic damage on outdoor materials, but the real chemical damage they are able to induce, in particular on metals, is not so well studied. This work focused on the short term role of uric acid, the main constituent of bird urine, with respect to copper, which make such an important contribution to architectural elements of buildings and outdoor sculpture. Preliminary results of laboratory tests and analyses on real exposed samples showed that uric acid chemically affects copper and bronzes: the surface of the metal is modified and copper urates formed. Also natural patina, formed on statues and roof, react with uric acid, even if it seems to afford some protection toward bird droppings. In general, experimental results confirm that the potential chemical damage by bird droppings is significant when considering external cultural heritage such as statues, metal monuments and buildings with historic copper roofs. PMID:19157513

  1. European Bronze Age Sheet Metal Objects: 3,000 Years of High-Level Bronze Manufacture

    NASA Astrophysics Data System (ADS)

    Mödlinger, Marianne; El Morr, Ziad

    2014-01-01

    This article focuses on the manufacture and usage of selected sheet metal objects from helmets, a vessel, and two shields from the European Bronze Age and Early Iron Age, which date from the thirteenth to seventh centuries BC. Manufacturing traces on the surface, as well as metallographic investigations and the analyses of the alloy composition with scanning electron microscope-energy-dispersive x-ray spectroscopy, provided an insight into the manufacturing techniques and the production of valuable, high-status objects, and highlighted the potential changes in manufacturing techniques and alloys used during different time periods.

  2. Does leaf position within a canopy affect acclimation of photosynthesis to elevated CO{sub 2}? Analysis of a wheat crop under free-air CO{sub 2} enrichment

    SciTech Connect

    Osborne, C.P.; LaRoche, J.; Hendrey, G.R.; Garcia, R.L.; Kimball, B.A.; Wall, G.W.; Pinter, P.J. Jr.; LaMorte, R.L.; Long, S.P. |

    1998-07-01

    Previous studies of photosynthetic acclimation to elevated CO{sub 2} have focused on the most recently expanded, sunlit leaves in the canopy. The authors examined acclimation in a vertical profile of leaves through a canopy of wheat (Triticum aestivum L.). The crop was grown at an elevated CO{sub 2} partial pressure of 55 Pa within a replicated field experiment using free-air CO{sub 2} enrichment. Gas exchange was used to estimate in vivo carboxylation capacity and the maximum rate of ribulose-1,5-bisphosphate-limited photosynthesis. Net photosynthetic CO{sub 2} uptake was measured for leaves in situ within the canopy. Leaf contents of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), light-harvesting-complex (LHC) proteins, and total N were determined. Elevated CO{sub 2} did not affect carboxylation capacity in the most recently expanded leaves but led to a decrease in lower, shaded leaves during grain development. Despite this acclimation, in situ photosynthetic CO{sub 2} uptake remained higher under elevated CO{sub 2}. Acclimation at elevated CO{sub 2} was accompanied by decreases in both Rubisco and total leaf N contents and an increase in LHC content. Elevated CO{sub 2} led to a larger increase in LHC/Rubisco in lower canopy leaves than in the uppermost leaf. Acclimation of leaf photosynthesis to elevated CO{sub 2} therefore depended on both vertical position within the canopy and the developmental stage.

  3. Release of copper from sintered tungsten-bronze shot under different pH conditions and its potential toxicity to aquatic organisms.

    PubMed

    Thomas, Vernon G; Santore, Robert C; McGill, Ian

    2007-03-01

    Sintered tungsten-bronze is a new substitute for lead shot, and is about to be deposited in and around the wetlands of North America. This material contains copper in the alloyed form of bronze. This in vitro study was performed according to U.S. Fish and Wildlife Service criteria to determine the dissolution rate of copper from the shot, and to assess the toxic risk that it may present to aquatic organisms. The dissolution of copper from tungsten-bronze shot, pure copper shot, and glass beads was measured in a buffered, moderately hard, synthetic water of pH 5.5, 6.6, and 7.8 over a 28-day period. The dissolution of copper from both the control copper shot and the tungsten-bronze shot was affected significantly by the pH of the water and the duration of dissolution (all p values<0.000). The rate of copper release from tungsten bronze shot was 30 to 50 times lower than that from the copper shot, depending on pH (p<0.0000). The observed expected environmental concentration of copper released from tungsten-bronze shot after 28 days was 0.02 microg/L at pH 7.8, and 0.4 microg/L at pH 5.6, using a loading and exposure scenario specific in a U.S. Fish and Wildlife Service protocol. Ratio Quotient values derived from the highest EEC observed in this study (0.4 microg/L), and the copper toxic effect levels for all aquatic species listed in the U.S. Environmental Protection Agency ambient water quality criteria database, were all far less than the 0.1 criterion value. Given the conditions stipulated by the U.S. Fish and Wildlife Service and the U.S. Environmental Protection Agency, heavy loading from discharged tungsten-bronze shot would not pose a toxic risk to potable water, or to soil. Consequently, it would appear that no toxic risks to aquatic organisms will attend the use of tungsten-bronze shot of the approved composition. Given the likelihood that sintered tungsten-bronze of the same formula will be used for fishing weights, bullets, and wheel balance weights, it

  4. Emptying and filling a tunnel bronze

    SciTech Connect

    Marley, Peter M.; Abtew, Tesfaye A.; Farley, Katie E.; Horrocks, Gregory A.; Dennis, Robert V.; Zhang, Peihong; Banerjee, Sarbajit

    2015-01-13

    The classical orthorhombic layered phase of V2O5 has long been regarded as the thermodynamic sink for binary vanadium oxides and has found great practical utility as a result of its open framework and easily accessible redox states. Herein, we exploit a cation-exchange mechanism to synthesize a new stable tunnel-structured polymorph of V2O5 (ζ-V2O5) and demonstrate the subsequent ability of this framework to accommodate Li and Mg ions. The facile extraction and insertion of cations and stabilization of the novel tunnel framework is facilitated by the nanometer-sized dimensions of the materials, which leads to accommodation of strain without amorphization. The topotactic approach demonstrated here indicates not just novel intercalation chemistry accessible at nanoscale dimensions but also suggests a facile synthetic route to ternary vanadium oxide bronzes (MxV2O5) exhibiting intriguing physical properties that range from electronic phase transitions to charge ordering and superconductivity.

  5. Emptying and filling a tunnel bronze

    DOE PAGESBeta

    Marley, Peter M.; Abtew, Tesfaye A.; Farley, Katie E.; Horrocks, Gregory A.; Dennis, Robert V.; Zhang, Peihong; Banerjee, Sarbajit

    2015-01-13

    The classical orthorhombic layered phase of V2O5 has long been regarded as the thermodynamic sink for binary vanadium oxides and has found great practical utility as a result of its open framework and easily accessible redox states. Herein, we exploit a cation-exchange mechanism to synthesize a new stable tunnel-structured polymorph of V2O5 (ζ-V2O5) and demonstrate the subsequent ability of this framework to accommodate Li and Mg ions. The facile extraction and insertion of cations and stabilization of the novel tunnel framework is facilitated by the nanometer-sized dimensions of the materials, which leads to accommodation of strain without amorphization. The topotacticmore » approach demonstrated here indicates not just novel intercalation chemistry accessible at nanoscale dimensions but also suggests a facile synthetic route to ternary vanadium oxide bronzes (MxV2O5) exhibiting intriguing physical properties that range from electronic phase transitions to charge ordering and superconductivity.« less

  6. Preparation of hydrated potassium molybdenum bronzes and their thermal decomposition

    SciTech Connect

    Sotani, Noriyuki; Suzuki, Takashi; Eda, Kazuo

    1997-09-01

    Three kinds of hydrated potassium bronze, K{sub 0.23}(H{sub 2}O){sub 0.65} MoO{sub 3.00} (HyK-AD), K{sub 0.23}(H{sub 2}O){sub 0.43}MoO{sub 3.00}(HyK-H2), and K{sub 0.23}(H{sub 2}O){sub 0.27}MoO{sub 3.00}(HyK-H1), were obtained from hydrated sodium bronzes by cation exchange. Hydrated potassium bronzes dried under vacuum are of two types. The first, HyK-H2 belongs to the six-coordination type and the second, HyK-H1, belongs to the eight-coordination type. When hydrated bronzes were heated in nitrogen, they turned into a mixture of the blue potassium bronze, K{sub 0.3}MoO{sub 3}, and MoO{sub 3}. In contrast, those heated in air decomposed to K{sub 2}Mo{sub 4}O{sub 13} and MoO{sub 3}.

  7. Setup of Galvanic Sensors for the Monitoring of Gilded Bronzes

    PubMed Central

    Goidanich, Sara; Gulotta, Davide; Brambilla, Laura; Beltrami, Ruben; Fermo, Paola; Toniolo, Lucia

    2014-01-01

    Traditional electrochemical techniques, such as linear polarization resistance (Rp), and electrochemical impedance spectroscopy (EIS), cannot be applied to gilded bronzes, as it may not be possible to interpret the results obtained due to the bimetallic nature of the studied material. The measurement of the macrocouple current generated by the gold/bronze galvanic couple can be used as an indicator of degradation processes. Nevertheless, this measurement cannot be performed directly on the original artifacts due to the systematic presence of short-circuits between the two metals. In the present work the use of galvanic sensors is proposed as a possible solution for the monitoring of gilded bronze artefacts. The sensors have been designed to simulate real gilded bronze surfaces in terms of composition and stratigraphy and have proved to be a reliable diagnostic tool for the in situ monitoring of the rates of deterioration of gilded bronze surfaces and to test new conservation treatments. Their set-up and application is reported and their performances discussed. PMID:24759110

  8. 76 FR 40402 - Matthews International Corporation, Bronze Division, Kingwood, WV; Notice of Negative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-08

    ..., 2011 (76 FR 7584). Workers were engaged in the production of cast bronze memorial products. The initial... Employment and Training Administration TA-W-72,953 Matthews International Corporation, Bronze Division... former workers of Matthews International Corporation, Bronze ] Division, Kingwood, West Virginia...

  9. Octahedral tilting in the tungsten bronzes.

    PubMed

    Whittle, Thomas A; Schmid, Siegbert; Howard, Christopher J

    2015-06-01

    Possibilities for 'simple' octahedral tilting in the hexagonal and tetragonal tungsten bronzes (HTB and TTB) have been examined, making use of group theory as implemented in the computer program ISOTROPY. For HTB, there is one obvious tilting pattern, leading to a structure in space group P6₃/mmc. This differs from the space group P6₃/mcm frequently quoted from X-ray studies – these studies have in effect detected only displacements of the W cations from the centres of the WO6 octahedra. The correct space group, taking account of both W ion displacement and the octahedral tilting, is P6₃22 – structures in this space group and matching this description have been reported. A second acceptable tilting pattern has been found, leading to a structure in P6/mmm but on a larger '2 × 2 × 2' unit cell – however, no observations of this structure have been reported. For TTB, a search at the special points of the Brillouin zones revealed only one comparable tilting pattern, in a structure with space-group symmetry I4/m on a '2(1/2) × 2(1/2) by 2' unit cell. Given several literature reports of larger unit cells for TTB, we conducted a limited search along the lines of symmetry and found structures with acceptable tilt patterns in Bbmm on a '2(1/2)2 × 2(1/2) × 2' unit cell. A non-centrosymmetric version has been reported in niobates, in Bbm2 on the same unit cell. PMID:26027010

  10. Leaf Development

    PubMed Central

    2013-01-01

    Leaves are the most important organs for plants. Without leaves, plants cannot capture light energy or synthesize organic compounds via photosynthesis. Without leaves, plants would be unable perceive diverse environmental conditions, particularly those relating to light quality/quantity. Without leaves, plants would not be able to flower because all floral organs are modified leaves. Arabidopsis thaliana is a good model system for analyzing mechanisms of eudicotyledonous, simple-leaf development. The first section of this review provides a brief history of studies on development in Arabidopsis leaves. This history largely coincides with a general history of advancement in understanding of the genetic mechanisms operating during simple-leaf development in angiosperms. In the second section, I outline events in Arabidopsis leaf development, with emphasis on genetic controls. Current knowledge of six important components in these developmental events is summarized in detail, followed by concluding remarks and perspectives. PMID:23864837

  11. Early Bronze Age Dolmens in Jordan and their orientations

    NASA Astrophysics Data System (ADS)

    Polcaro, A.; Polcaro, F.

    This work presents the results of a survey of dolmen fields of the Early Bronze I in Jordan, in the Wadi Zarqa Valley, started in October 2004 and still in progress. Our data show, with a very high statistical significance, that in many sites of the Early Bronze IA a large majority of dolmens were built oriented along the N-S direction. A first interpretative hypothesis of these results, based on the astronomical contents of the mythology of the nearby civilizations culturally connected to the Palestinian area, is suggested.

  12. Electronic band structure and charge density wave transition in quasi-2D KMo6O17 purple bronze

    NASA Astrophysics Data System (ADS)

    Valbuena, M. A.; Avila, J.; Vyalikh, D. V.; Guyot, H.; Laubschat, C.; Molodtsov, S. L.; Asensio, M. C.

    2008-03-01

    High resolution angle-resolved photoemission of quasi-2D KMo6O17 purple bronze has been performed in the range from room temperature to 130 K, slightly above the charge density wave (CDW) transition (Tc = 110 K), and down to 35 K (well below Tc). In this paper we report a detailed study of how electronic band structure is affected by this transition driven by the hidden nesting scenario. The expected spectroscopic fingerprints of the CDW phase transition have been found and discussed according to the hidden one dimension and the development of a quasi-commensurate CDW. The excellent agreement between theory and our experimental results makes of potassium purple bronze a reference system for studying this type of instabilities.

  13. Effect of herbivore damage on broad leaf motion in wind

    NASA Astrophysics Data System (ADS)

    Burnett, Nicholas; Kothari, Adit

    2015-11-01

    Terrestrial plants regularly experience wind that imposes aerodynamic forces on the plants' leaves. Passive leaf motion (e.g. fluttering) and reconfiguration (e.g. rolling into a cone shape) in wind can affect the drag on the leaf. In the study of passive leaf motion in wind, little attention has been given to the effect of herbivory. Herbivores may alter leaf motion in wind by making holes in the leaf. Also, a small herbivore (e.g. snail) on a leaf can act as a point mass, thereby affecting the leaf's motion in wind. Conversely, accelerations imposed on an herbivore sitting on a leaf by the moving leaf may serve as a defense by dislodging the herbivore. In the present study, we investigated how point masses (>1 g) and holes in leaves of the tuliptree affected passive leaf motion in turbulent winds of 1 and 5 m s-1. Leaf motion was unaffected by holes in the leaf surface (about 10% of leaf area), but an herbivore's mass significantly damped the accelerations of fluttering leaves. These results suggest that an herbivore's mass, but not the damage it inflicts, can affect leaf motion in the wind. Furthermore, the damping of leaf fluttering from an herbivore's mass may prevent passive leaf motions from being an effective herbivore defense.

  14. SPAD-based leaf nitrogen estimation is impacted by environmental factors and crop leaf characteristics

    PubMed Central

    Xiong, Dongliang; Chen, Jia; Yu, Tingting; Gao, Wanlin; Ling, Xiaoxia; Li, Yong; Peng, Shaobing; Huang, Jianliang

    2015-01-01

    Chlorophyll meters are widely used to guide nitrogen (N) management by monitoring leaf N status in agricultural systems, but the effects of environmental factors and leaf characteristics on leaf N estimations are still unclear. In the present study, we estimated the relationships among SPAD readings, chlorophyll content and leaf N content per leaf area for seven species grown in multiple environments. There were similar relationships between SPAD readings and chlorophyll content per leaf area for the species groups, but the relationship between chlorophyll content and leaf N content per leaf area, and the relationship between SPAD readings and leaf N content per leaf area varied widely among the species groups. A significant impact of light-dependent chloroplast movement on SPAD readings was observed under low leaf N supplementation in both rice and soybean but not under high N supplementation. Furthermore, the allocation of leaf N to chlorophyll was strongly influenced by short-term changes in growth light. We demonstrate that the relationship between SPAD readings and leaf N content per leaf area is profoundly affected by environmental factors and leaf features of crop species, which should be accounted for when using a chlorophyll meter to guide N management in agricultural systems. PMID:26303807

  15. Origin of the mysterious Yin-Shang bronzes in China indicated by lead isotopes

    PubMed Central

    Sun, Wei-dong; Zhang, Li-peng; Guo, Jia; Li, Cong-ying; Jiang, Yu-hang; Zartman, Robert E.; Zhang, Zhao-feng

    2016-01-01

    Fine Yin-Shang bronzes containing lead with puzzlingly highly radiogenic isotopic compositions appeared suddenly in the alluvial plain of the Yellow River around 1400 BC. The Tongkuangyu copper deposit in central China is known to have lead isotopic compositions even more radiogenic and scattered than those of the Yin-Shang bronzes. Most of the Yin-Shang bronzes are tin-copper alloys with high lead contents. The low lead and tin concentrations, together with the less radiogenic lead isotopes of bronzes in an ancient smelting site nearby, however, exclude Tongkuangyu as the sole supplier of the Yin-Shang bronzes. Interestingly, tin ingots/prills and bronzes found in Africa also have highly radiogenic lead isotopes, but it remains mysterious as to how such African bronzes may have been transported to China. Nevertheless, these African bronzes are the only bronzes outside China so far reported that have lead isotopes similar to those of the Yin-Shang bronzes. All these radiogenic lead isotopes plot along ~2.0–2.5 Ga isochron lines, implying that deposits around Archean cratons are the most likely candidates for the sources. African cratons along the Nile and even micro-cratons in the Sahara desert may have similar lead signatures. These places were probably accessible by ancient civilizations, and thus are the most favorable suppliers of the bronzes. PMID:26988425

  16. Origin of the mysterious Yin-Shang bronzes in China indicated by lead isotopes.

    PubMed

    Sun, Wei-Dong; Zhang, Li-Peng; Guo, Jia; Li, Cong-Ying; Jiang, Yu-Hang; Zartman, Robert E; Zhang, Zhao-Feng

    2016-01-01

    Fine Yin-Shang bronzes containing lead with puzzlingly highly radiogenic isotopic compositions appeared suddenly in the alluvial plain of the Yellow River around 1400 BC. The Tongkuangyu copper deposit in central China is known to have lead isotopic compositions even more radiogenic and scattered than those of the Yin-Shang bronzes. Most of the Yin-Shang bronzes are tin-copper alloys with high lead contents. The low lead and tin concentrations, together with the less radiogenic lead isotopes of bronzes in an ancient smelting site nearby, however, exclude Tongkuangyu as the sole supplier of the Yin-Shang bronzes. Interestingly, tin ingots/prills and bronzes found in Africa also have highly radiogenic lead isotopes, but it remains mysterious as to how such African bronzes may have been transported to China. Nevertheless, these African bronzes are the only bronzes outside China so far reported that have lead isotopes similar to those of the Yin-Shang bronzes. All these radiogenic lead isotopes plot along ~2.0-2.5 Ga isochron lines, implying that deposits around Archean cratons are the most likely candidates for the sources. African cratons along the Nile and even micro-cratons in the Sahara desert may have similar lead signatures. These places were probably accessible by ancient civilizations, and thus are the most favorable suppliers of the bronzes. PMID:26988425

  17. Origin of the mysterious Yin-Shang bronzes in China indicated by lead isotopes

    NASA Astrophysics Data System (ADS)

    Sun, Wei-Dong; Zhang, Li-Peng; Guo, Jia; Li, Cong-Ying; Jiang, Yu-Hang; Zartman, Robert E.; Zhang, Zhao-Feng

    2016-03-01

    Fine Yin-Shang bronzes containing lead with puzzlingly highly radiogenic isotopic compositions appeared suddenly in the alluvial plain of the Yellow River around 1400 BC. The Tongkuangyu copper deposit in central China is known to have lead isotopic compositions even more radiogenic and scattered than those of the Yin-Shang bronzes. Most of the Yin-Shang bronzes are tin-copper alloys with high lead contents. The low lead and tin concentrations, together with the less radiogenic lead isotopes of bronzes in an ancient smelting site nearby, however, exclude Tongkuangyu as the sole supplier of the Yin-Shang bronzes. Interestingly, tin ingots/prills and bronzes found in Africa also have highly radiogenic lead isotopes, but it remains mysterious as to how such African bronzes may have been transported to China. Nevertheless, these African bronzes are the only bronzes outside China so far reported that have lead isotopes similar to those of the Yin-Shang bronzes. All these radiogenic lead isotopes plot along ~2.0–2.5 Ga isochron lines, implying that deposits around Archean cratons are the most likely candidates for the sources. African cratons along the Nile and even micro-cratons in the Sahara desert may have similar lead signatures. These places were probably accessible by ancient civilizations, and thus are the most favorable suppliers of the bronzes.

  18. BRONZE WILT AS A CAUSE OF YIELD STAGNATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cultivars and breeding lines submitted for the 2000 Uniform Variety Trials were inoculated with Agrobacterium tumefaciens isolate 25A, grown in the greenhouse, and observed for plant development, yield, seed quality, bronze wilt, root necrosis, and bacterial concentration in roots. Losses from bron...

  19. Reporting Casting Bronze Plaque Becomes Advisers Class Project

    ERIC Educational Resources Information Center

    Ross, Charlie

    1977-01-01

    Describes an advisers' class project (at the University of Oklahoma) which consisted of reporting on the casting of a bronze plaque bearing the names of the first school newspaper, "The Students Gazette," and its editor, Samuel M. Fox, for presentation in Philadelphia to commemorate scholastic journalism's Bicentennial. (MB)

  20. INTERIOR DETAIL, EASTERN HEMICYCLE, SALOON. WILLIAM HAMILTON PLACED BRONZE AND ...

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

    INTERIOR DETAIL, EASTERN HEMICYCLE, SALOON. WILLIAM HAMILTON PLACED BRONZE AND MARBLE SCULPTURE IN SOME OF THE HEMICYCLE NICHES. ONE OF THE NICHES HOUSED A “CANNON STOVE” FOR HEATING THE ROOM IN THE COLDER MONTHS - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

  1. DETAIL OF ORIGINAL PHOSPHOR BRONZE PLATE PLACED OVER A BULLSEYE ...

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

    DETAIL OF ORIGINAL PHOSPHOR BRONZE PLATE PLACED OVER A BULLSEYE REFLECTOR THAT WAS AIMED AT ONCOMING TRAFFIC. THE TOP OF A CIRCULAR VOID CAN BE SEEN BELOW THE PLATE WHERE THE REFLECTOR WAS REMOVED. VIEW FACING SOUTHWEST. - Waikele Canal Bridge and Highway Overpass, Farrington Highway and Waikele Stream, Waipahu, Honolulu County, HI

  2. Detail view to show the bronze gates hanging in the ...

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

    Detail view to show the bronze gates hanging in the driveway portals; the open grille is foliated and crowned with patriotic eagle emblems - United States Department of Commerce, Bounded by Fourteenth, Fifteenth, and E streets and Constitution Avenue, Washington, District of Columbia, DC

  3. BRONZE FOUNDRY SCRAP STORED IN THE BINS TO THE RIGHT ...

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

    BRONZE FOUNDRY SCRAP STORED IN THE BINS TO THE RIGHT ARE LOADED INTO THE BOTTOM DROPPING CHARGE BUCKET IN THE BACKGROUND BEFORE BEING CHARGED INTO ONE OF THE ELECTRIC ARC FURNACES. - Stockham Pipe & Fittings Company, Brass Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  4. VIEW OF A BRONZE PLAQUE LOCATED AT THE FRONT OF ...

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

    VIEW OF A BRONZE PLAQUE LOCATED AT THE FRONT OF BUILDING 708. PLAQUE IS MOUNTED ON THE WALL JUST TO THE RIGHT SIDE OF THE CHAPEL'S ENTRANCE. - U.S. Naval Base, Pearl Harbor, Chapel, Corner of Oakley & Nimitz Street, Pearl City, Honolulu County, HI

  5. TILTING ELECTRIC ARC FURNACE USED TO MELT BRONZE IN THE ...

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

    TILTING ELECTRIC ARC FURNACE USED TO MELT BRONZE IN THE BRASS FOUNDRY BY MEANS OF AN ARC CREATED BETWEEN TWO HORIZONTAL ELECTRODES. WHEN MELTED, THE FURNACE TILTS, FILLING MOBILE LADLES FROM THE SPOUT. - Stockham Pipe & Fittings Company, Brass Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  6. Formation of tetragonal hydrogen tungsten bronze by reactive mechanical alloying

    SciTech Connect

    Urretavizcaya, G. Tonus, F.; Gaudin, E.; Bobet, J.-L.; Castro, F.J.

    2007-10-15

    Hydrogen tungsten bronzes have been synthesized by reactive mechanical alloying monoclinic tungsten (VI) oxide under hydrogen atmosphere. Two milling devices with different energy ranges were used. Regardless of the distinct reaction times, a similar phase evolution was observed with both apparatus. The characterization of the materials was performed by XRD, SEM, DSC and total hydrogen content determination. The final product obtained was a mixture of tetragonal H{sub 0.33}WO{sub 3} and H{sub 0.23}WO{sub 3} bronzes. - Graphical abstract: Hydrogen tungsten bronzes have been synthesized by reactive mechanical alloying (RMA) monoclinic WO{sub 3} under H{sub 2} atmosphere. By using two milling devices with different energy ranges a similar phase evolution with distinct reaction times was observed. The materials were characterized by XRD, SEM, DSC and total hydrogen content determination. The final product obtained was a mixture of tetragonal H{sub 0.33}WO{sub 3} and H{sub 0.23}WO{sub 3} bronzes. Display Omitted.

  7. Going for the Bronze: A Study of Frederic Remington's Sculptures.

    ERIC Educational Resources Information Center

    Turner, Dianne

    2002-01-01

    Provides background information on the artist Frederic Remington who was fascinated with the Old West in the United States. Discusses how students can learn about Remington, his art, and the Old West. Presents an art lesson where students create their own bronze horse sculptures in the style of Remington. (CMK)

  8. 17. DETAIL OF THE BRONZE INSCRIPTION PLACQUE, LOCATED IN A ...

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

    17. DETAIL OF THE BRONZE INSCRIPTION PLACQUE, LOCATED IN A NEWEL ON THE SOUTH END OF THE BRIDGE. ALTHOUGH THE DATE ON THE PLACQUE IS 1929, THE BRIDGE WAS NOT DEDICATED UNTIL 1930. - County Line Bridge, Spanning St. Joseph River at State Route 219, 0.6 mile south of U.S. Route 20, Osceola, St. Joseph County, IN

  9. 26. A PHOTOGRAPH OF ONE OF THE TWO BRONZE, LOWRELIEF ...

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

    26. A PHOTOGRAPH OF ONE OF THE TWO BRONZE, LOW-RELIEF COMMEMORATIVE PLACQUES WHICH ARE MOUNTED ON PEDESTALS AT THE NORTHEAST AND SOUTHWEST ENDS OF THE BRIDGE. NOTE THE PRONOUNCED PEBBLE-DASH FINISH ON THE CONCRETE WHICH WAS CREATED, IN PART, BY WASHING THE DAMP CASTINGS. - Main Street Bridge, Spanning East Fork Whitewater River, Richmond, Wayne County, IN

  10. BRASS FOUNDRY BUILDING WHERE STOCKHAM MANUFACTURED ITS BRONZE VALVES AND ...

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

    BRASS FOUNDRY BUILDING WHERE STOCKHAM MANUFACTURED ITS BRONZE VALVES AND VALVE PARTS. ALTHOUGH THE COMPANY DID NOT PRODUCE BRASS CASTINGS, ITS EQUIPMENT WAS SIMILAR TO THAT USED IN BRASS FOUNDRIES AND MAY HAVE BEEN PART OF LONG RANGE PLAN TO CAST BRASS. - Stockham Pipe & Fittings Company, Brass Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  11. Community Geothermal Technology Program: Silica bronze project. Final report

    SciTech Connect

    Bianchini, H.

    1989-10-01

    Objective was to incorporate waste silica from the HGP-A geothermal well in Pohoiki with other refractory materials for investment casting of bronze sculpture. The best composition for casting is about 50% silica, 25% red cinders, and 25% brick dust; remaining ingredient is a binder, such as plaster and water.

  12. Prehistoric contacts over the Straits of Gibraltar indicated by genetic analysis of Iberian Bronze Age cattle

    PubMed Central

    Anderung, Cecilia; Bouwman, Abigail; Persson, Per; Carretero, José Miguel; Ortega, Ana Isabel; Elburg, Rengert; Smith, Colin; Arsuaga, Juan Luis; Ellegren, Hans; Götherström, Anders

    2005-01-01

    The geographic situation of the Iberian Peninsula makes it a natural link between Europe and North Africa. However, it is a matter of debate to what extent African influences via the Straits Gibraltar have affected Iberia's prehistoric development. Because early African pastoralist communities were dedicated to cattle breeding, a possible means to detect prehistoric African–Iberian contacts might be to analyze the origin of cattle breeds on the Iberian Peninsula. Some contemporary Iberian cattle breeds show a mtDNA haplotype, T1, that is characteristic to African breeds, generally explained as being the result of the Muslim expansion of the 8th century A.D., and of modern imports. To test a possible earlier African influence, we analyzed mtDNA of Bronze Age cattle from the Portalón cave at the Atapuerca site in northern Spain. Although the majority of samples showed the haplotype T3 that dominates among European breeds of today, the T1 haplotype was found in one specimen radiocarbon dated 1800 calibrated years B.C. Accepting T1 as being of African origin, this result indicates prehistoric African–Iberian contacts and lends support to archaeological finds linking early African and Iberian cultures. We also found a wild ox haplotype in the Iberian Bronze Age sample, reflecting local hybridization or backcrossing or that aurochs were hunted by these farming cultures. PMID:15941827

  13. Alterations of the gut microbiome of largemouth bronze gudgeon (Coreius guichenoti) suffering from furunculosis

    PubMed Central

    Li, Tongtong; Long, Meng; Ji, Cheng; Shen, Zhixin; Gatesoupe, François-Joël; Zhang, Xujie; Zhang, Qianqian; Zhang, Lanli; Zhao, Yuanli; Liu, Xinhua; Li, Aihua

    2016-01-01

    High-throughput sequencing was applied to compare the intestinal microbiota in largemouth bronze gudgeon either healthy or affected by furunculosis. Proteobacteria, Actinobacteria, Tenericutes, Firmicutes and Bacteroidetes were detected as the predominant bacterial phyla in the gut of both diseased and healthy fish. The abundance of Proteobacteria differed significantly between the two groups of fish, mainly due to the overwhelming prevalence of Aeromonas in the diseased fish (81% ± 17%), while the genus was unevenly spread among the apparently healthy fish (33% ± 33%). The bacterial diversity in the intestine of diseased fish was markedly lower than in healthy fish. Analysis revealed the significant dissimilarity between the gut microbiota of diseased and healthy fish. The bacterial profiles in the gut were further characterized with the 28 phylotypes that were shared by the two groups. In diseased fish, two shared OTUs (OTU0001 and OTU0013) were closely related to Aeromonas salmonicida, their total proportion exceeding 70% of the sequences in diseased fish, while averaging 5.2% ± 4.6% in the healthy fish. This result suggested the presence of healthy carriers of pathogenic A. salmonicida among the farmed fish, and the gut appeared as a probable infection source for furunculosis in largemouth bronze gudgeon. PMID:27465687

  14. Alterations of the gut microbiome of largemouth bronze gudgeon (Coreius guichenoti) suffering from furunculosis.

    PubMed

    Li, Tongtong; Long, Meng; Ji, Cheng; Shen, Zhixin; Gatesoupe, François-Joël; Zhang, Xujie; Zhang, Qianqian; Zhang, Lanli; Zhao, Yuanli; Liu, Xinhua; Li, Aihua

    2016-01-01

    High-throughput sequencing was applied to compare the intestinal microbiota in largemouth bronze gudgeon either healthy or affected by furunculosis. Proteobacteria, Actinobacteria, Tenericutes, Firmicutes and Bacteroidetes were detected as the predominant bacterial phyla in the gut of both diseased and healthy fish. The abundance of Proteobacteria differed significantly between the two groups of fish, mainly due to the overwhelming prevalence of Aeromonas in the diseased fish (81% ± 17%), while the genus was unevenly spread among the apparently healthy fish (33% ± 33%). The bacterial diversity in the intestine of diseased fish was markedly lower than in healthy fish. Analysis revealed the significant dissimilarity between the gut microbiota of diseased and healthy fish. The bacterial profiles in the gut were further characterized with the 28 phylotypes that were shared by the two groups. In diseased fish, two shared OTUs (OTU0001 and OTU0013) were closely related to Aeromonas salmonicida, their total proportion exceeding 70% of the sequences in diseased fish, while averaging 5.2% ± 4.6% in the healthy fish. This result suggested the presence of healthy carriers of pathogenic A. salmonicida among the farmed fish, and the gut appeared as a probable infection source for furunculosis in largemouth bronze gudgeon. PMID:27465687

  15. LeafJ: an ImageJ plugin for semi-automated leaf shape measurement.

    PubMed

    Maloof, Julin N; Nozue, Kazunari; Mumbach, Maxwell R; Palmer, Christine M

    2013-01-01

    High throughput phenotyping (phenomics) is a powerful tool for linking genes to their functions (see review and recent examples). Leaves are the primary photosynthetic organ, and their size and shape vary developmentally and environmentally within a plant. For these reasons studies on leaf morphology require measurement of multiple parameters from numerous leaves, which is best done by semi-automated phenomics tools. Canopy shade is an important environmental cue that affects plant architecture and life history; the suite of responses is collectively called the shade avoidance syndrome (SAS). Among SAS responses, shade induced leaf petiole elongation and changes in blade area are particularly useful as indices. To date, leaf shape programs (e.g. SHAPE, LAMINA, LeafAnalyzer, LEAFPROCESSOR) can measure leaf outlines and categorize leaf shapes, but can not output petiole length. Lack of large-scale measurement systems of leaf petioles has inhibited phenomics approaches to SAS research. In this paper, we describe a newly developed ImageJ plugin, called LeafJ, which can rapidly measure petiole length and leaf blade parameters of the model plant Arabidopsis thaliana. For the occasional leaf that required manual correction of the petiole/leaf blade boundary we used a touch-screen tablet. Further, leaf cell shape and leaf cell numbers are important determinants of leaf size. Separate from LeafJ we also present a protocol for using a touch-screen tablet for measuring cell shape, area, and size. Our leaf trait measurement system is not limited to shade-avoidance research and will accelerate leaf phenotyping of many mutants and screening plants by leaf phenotyping. PMID:23380664

  16. Identification of Plants That Inhibit Lipid Droplet Formation in Liver Cells: Rubus suavissimus Leaf Extract Protects Mice from High-Fat Diet-Induced Fatty Liver by Directly Affecting Liver Cells

    PubMed Central

    Takahashi, Tomohiro; Sugawara, Wataru; Takiguchi, Yuya; Takizawa, Kento; Nakabayashi, Ami; Nakamura, Mitsuo; Nagano-Ito, Michiyo; Ichikawa, Shinichi

    2016-01-01

    Fatty liver disease is a condition in which abnormally large numbers of lipid droplets accumulate in liver cells. Fatty liver disease induces inflammation under conditions of oxidative stress and may result in cancer. To identify plants that protect against fatty liver disease, we examined the inhibitory effects of plant extracts on lipid droplet formation in mouse hepatoma cells. A screen of 98 water extracts of plants revealed 4 extracts with inhibitory effects. One of these extracts, Rubus suavissimus S. Lee (Tien-cha or Chinese sweet tea) leaf extract, which showed strong inhibitory effects, was tested in a mouse fatty liver model. In these mouse experiments, intake of the plant extract significantly protected mice against fatty liver disease without affecting body weight gain. Our results suggest that RSE directly affects liver cells and protects them from fatty liver disease. PMID:27429636

  17. Identification of Plants That Inhibit Lipid Droplet Formation in Liver Cells: Rubus suavissimus Leaf Extract Protects Mice from High-Fat Diet-Induced Fatty Liver by Directly Affecting Liver Cells.

    PubMed

    Takahashi, Tomohiro; Sugawara, Wataru; Takiguchi, Yuya; Takizawa, Kento; Nakabayashi, Ami; Nakamura, Mitsuo; Nagano-Ito, Michiyo; Ichikawa, Shinichi

    2016-01-01

    Fatty liver disease is a condition in which abnormally large numbers of lipid droplets accumulate in liver cells. Fatty liver disease induces inflammation under conditions of oxidative stress and may result in cancer. To identify plants that protect against fatty liver disease, we examined the inhibitory effects of plant extracts on lipid droplet formation in mouse hepatoma cells. A screen of 98 water extracts of plants revealed 4 extracts with inhibitory effects. One of these extracts, Rubus suavissimus S. Lee (Tien-cha or Chinese sweet tea) leaf extract, which showed strong inhibitory effects, was tested in a mouse fatty liver model. In these mouse experiments, intake of the plant extract significantly protected mice against fatty liver disease without affecting body weight gain. Our results suggest that RSE directly affects liver cells and protects them from fatty liver disease. PMID:27429636

  18. Rewriting the Central European Early Bronze Age Chronology: Evidence from Large-Scale Radiocarbon Dating.

    PubMed

    Stockhammer, Philipp W; Massy, Ken; Knipper, Corina; Friedrich, Ronny; Kromer, Bernd; Lindauer, Susanne; Radosavljević, Jelena; Wittenborn, Fabian; Krause, Johannes

    2015-01-01

    The transition from the Neolithic to the Early Bronze Age in Central Europe has often been considered as a supra-regional uniform process, which led to the growing mastery of the new bronze technology. Since the 1920s, archaeologists have divided the Early Bronze Age into two chronological phases (Bronze A1 and A2), which were also seen as stages of technical progress. On the basis of the early radiocarbon dates from the cemetery of Singen, southern Germany, the beginning of the Early Bronze Age in Central Europe was originally dated around 2300/2200 BC and the transition to more complex casting techniques (i.e., Bronze A2) around 2000 BC. On the basis of 140 newly radiocarbon dated human remains from Final Neolithic, Early and Middle Bronze Age cemeteries south of Augsburg (Bavaria) and a re-dating of ten graves from the cemetery of Singen, we propose a significantly different dating range, which forces us to re-think the traditional relative and absolute chronologies as well as the narrative of technical development. We are now able to date the beginning of the Early Bronze Age to around 2150 BC and its end to around 1700 BC. Moreover, there is no transition between Bronze (Bz) A1 and Bronze (Bz) A2, but a complete overlap between the type objects of the two phases from 1900-1700 BC. We thus present a revised chronology of the assumed diagnostic type objects of the Early Bronze Age and recommend a radiocarbon-based view on the development of the material culture. Finally, we propose that the traditional phases Bz A1 and Bz A2 do not represent a chronological sequence, but regionally different social phenomena connected to the willingness of local actors to appropriate the new bronze technology. PMID:26488413

  19. Rewriting the Central European Early Bronze Age Chronology: Evidence from Large-Scale Radiocarbon Dating

    PubMed Central

    Knipper, Corina; Friedrich, Ronny; Kromer, Bernd; Lindauer, Susanne; Radosavljević, Jelena; Wittenborn, Fabian; Krause, Johannes

    2015-01-01

    The transition from the Neolithic to the Early Bronze Age in Central Europe has often been considered as a supra-regional uniform process, which led to the growing mastery of the new bronze technology. Since the 1920s, archaeologists have divided the Early Bronze Age into two chronological phases (Bronze A1 and A2), which were also seen as stages of technical progress. On the basis of the early radiocarbon dates from the cemetery of Singen, southern Germany, the beginning of the Early Bronze Age in Central Europe was originally dated around 2300/2200 BC and the transition to more complex casting techniques (i.e., Bronze A2) around 2000 BC. On the basis of 140 newly radiocarbon dated human remains from Final Neolithic, Early and Middle Bronze Age cemeteries south of Augsburg (Bavaria) and a re-dating of ten graves from the cemetery of Singen, we propose a significantly different dating range, which forces us to re-think the traditional relative and absolute chronologies as well as the narrative of technical development. We are now able to date the beginning of the Early Bronze Age to around 2150 BC and its end to around 1700 BC. Moreover, there is no transition between Bronze (Bz) A1 and Bronze (Bz) A2, but a complete overlap between the type objects of the two phases from 1900–1700 BC. We thus present a revised chronology of the assumed diagnostic type objects of the Early Bronze Age and recommend a radiocarbon-based view on the development of the material culture. Finally, we propose that the traditional phases Bz A1 and Bz A2 do not represent a chronological sequence, but regionally different social phenomena connected to the willingness of local actors to appropriate the new bronze technology. PMID:26488413

  20. Hormonal regulation of leaf senescence in Lilium.

    PubMed

    Arrom, Laia; Munné-Bosch, Sergi

    2012-10-15

    In addition to floral senescence and longevity, the control of leaf senescence is a major factor determining the quality of several cut flowers, including Lilium, in the commercial market. To better understand the physiological process underlying leaf senescence in this species, we evaluated: (i) endogenous variation in the levels of phytohormones during leaf senescence, (ii) the effects of leaf darkening in senescence and associated changes in phytohormones, and (iii) the effects of spray applications of abscisic acid (ABA) and pyrabactin on leaf senescence. Results showed that while gibberellin 4 (GA(4)) and salicylic acid (SA) contents decreased, that of ABA increased during the progression of leaf senescence. However, dark-induced senescence increased ABA levels, but did not affect GA(4) and SA levels, which appeared to correlate more with changes in air temperature and/or photoperiod than with the induction of leaf senescence. Furthermore, spray applications of pyrabactin delayed the progression of leaf senescence in cut flowers. Thus, we conclude that (i) ABA plays a major role in the regulation of leaf senescence in Lilium, (ii) darkness promotes leaf senescence and increases ABA levels, and (iii) exogenous applications of pyrabactin inhibit leaf senescence in Lilium, therefore suggesting that it acts as an antagonist of ABA in senescing leaves of cut lily flowers. PMID:22854182

  1. Casting Simulation of an Austrian Bronze Age Sword Hilt

    NASA Astrophysics Data System (ADS)

    Pola, Annalisa; Mödlinger, Marianne; Piccardo, Paolo; Montesano, Lorenzo

    2015-07-01

    Bronze Age swords with a metal hilt can be considered the peak of Bronze Age casting technologies. To reconstruct the casting techniques used more than 3000 years ago, a metal hilted sword of the Schalenknauf type from Lower Austria was studied with the aid of macroscopic analyses and simulation of mold filling and casting solidification. A three-dimensional model of the hilt was created based on optical scanner measurements performed on a hilt recently discovered during archaeological excavations. Three different configurations of the gating system were considered, two on the pommel disk and one on the knob, and the effect of its location on the formation of casting defects was investigated. Three-dimensional computed tomography was used to detect internal defects, such as gas and shrinkage porosity, which were then compared with those calculated by simulation. The best match between actual and predicted hilt quality demonstrated the location of the gating system, which turned out to be on the pommel disk.

  2. Effectiveness of copper and bronze for zinc capture

    SciTech Connect

    Korinko, P. S.

    2012-10-15

    A series of experiments was conducted to determine the efficacy of using copper and bronze sheet and screen under high vacuum conditions to capture zinc vapor. The experiments were conducted in a parametric manner using a fixed zinc vaporization temperature (350°C) but varying the filter temperature from ambient to 550°C. Consistent with previous work, metallic zinc was deposited at low temperatures, but the deposit was non-adherent. At an intermediate temperature range (350-450°C), the deposit formed an alloy with both copper and bronze materials. At higher temperatures (> 500°C) the zinc did not deposit on the surfaces likely due to its high vapor pressure. Additional testing to optimize the zinc 'getter' chemistry and surface condition is warranted.

  3. Nettle as a distinct Bronze Age textile plant

    PubMed Central

    Bergfjord, C.; Mannering, U.; Frei, K. M.; Gleba, M.; Scharff, A. B.; Skals, I.; Heinemeier, J.; Nosch, M. -L; Holst, B.

    2012-01-01

    It is generally assumed that the production of plant fibre textiles in ancient Europe, especially woven textiles for clothing, was closely linked to the development of agriculture through the use of cultivated textile plants (flax, hemp). Here we present a new investigation of the 2800 year old Lusehøj Bronze Age Textile from Voldtofte, Denmark, which challenges this assumption. We show that the textile is made of imported nettle, most probably from the Kärnten-Steiermark region, an area which at the time had an otherwise established flax production. Our results thus suggest that the production of woven plant fibre textiles in Bronze Age Europe was based not only on cultivated textile plants but also on the targeted exploitation of wild plants. The Lusehøj find points to a hitherto unrecognized role of nettle as an important textile plant and suggests the need for a re-evaluation of textile production resource management in prehistoric Europe. PMID:23024858

  4. Possible toxic metal exposure of prehistoric bronze workers.

    PubMed Central

    Harper, M

    1987-01-01

    An attempt has been made to assess the possible occupational exposure to arsenic, lead, and mercury during the Bronze Age. Archaeological, metallurgical, and historical evidence is combined to form a picture of the potential toxic hazards. In the case of arsenic a definite picture emerges of the effect of toxicity as a useful material is abandoned for health reasons on discovery of an acceptable alternative. Images PMID:3314977

  5. Effect of alloying elements on the physicomechanical properties of copper and tin bronze

    NASA Astrophysics Data System (ADS)

    Ri, Kh.; Komkov, V. G.; Ri, E. Kh.

    2014-09-01

    The effect of alloying elements (Al, Si, Mn, Zn, Ni, As) on the physicomechanical properties of copper and tin bronze (6 wt % Sn) is studied. These alloying elements are found to increase the hardness and the microhardness of the structural constituents of Cu- X alloys due to hardening the α solid solution and eutectoid, and this effect of alloying elements is most effective in tin bronze. Alloyed copper and tin bronze have a lower thermal conductivity and corrosion resistance as compared to plain copper and tin bronze.

  6. Tamil Chola Bronzes and Swamimalai Legacy: Metal Sources and Archaeotechnology

    NASA Astrophysics Data System (ADS)

    Srinivasan, Sharada

    2016-05-01

    This review explores the great copper alloy image casting traditions of southern India from archaeometallurgical and ethnometallurgical perspectives. The usefulness of lead isotope ratio and compositional analysis in the finger-printing and art historical study of more than 130 early historic, Pallava, Chola, later Chola, and Vijayanagara sculptures (fifth-eighteenth centuries) is highlighted, including Nataraja, Buddha, Parvati, and Rama images made of copper, leaded bronze, brass, and gilt copper. Image casting traditions at Swamimalai in Tamil Nadu are compared with artistic treatises and with the technical examination of medieval bronzes, throwing light on continuities and changes in foundry practices. Western Indian sources could be pinpointed for a couple of medieval images from lead isotope analysis. Slag and archaeometallurgical investigations suggest the exploitation of some copper and lead-silver sources in the Andhra and Karnataka regions in the early historic Satavahana period and point to probable copper sources for the medieval images in Karnataka, Tamil Nadu, and Andhra Pradesh. The general lower iron content in southern Indian bronzes perhaps renders the proximal copper-magnetite reserves of Seruvila in Sri Lanka as a less likely source. Given the lack of lead deposits in Sri Lanka, however, the match of the lead isotope signatures of a well-known Ceylonese Buddhist Tara in British Museum with a Buddha image from Nagapattinam in Tamil Nadu may underscore ties between the island nation and the southern Indian Tamil regions.

  7. Lithium vanadium bronze thin films for electrochromic applications

    SciTech Connect

    Green, M.; Pita, K.

    1997-04-01

    Thin films of fine grained polycrystalline stoichiometric vanadium pentoxide (85{percent} of bulk density) have been prepared by vacuum evaporation. These films have been made into lithium vanadium bronze, Li{sub x}V{sub 2}O{sub 5}, by inserting lithium, either electrochemically or chemically. In addition, lithium vanadium bronze thin films have been prepared by co-evaporation of Li and V{sub 2}O{sub 5}. The optical properties, absorption and refractive index, have been measured from 2000 to about 200 nm. Strong absorption arises from indirect transitions across the main gap and is {approx}2.2 eV for x=0. The variation of the energy gap up to an x value of 2 has been obtained from the absorption data and the importance of irreversible phase changes noted. High x value bronze is useful as a counter electrode material in glazings, having an energy gap of about 3 eV. There is a considerable, technologically significant, band tail in the absorption spectrum thought to arise from polaronic-type states, perhaps modified by the presence of guest species ions. The optical behavior upon lithium electrochemical insertion has also been examined. It is found that nonstoichiometry gives rise to an overall reduction in optical change per guest atom inserted. These effects are fast compared with electrochemical insertion times. {copyright} {ital 1997 American Institute of Physics.}

  8. Portable EDXRF investigation of the patinas on the Riace Bronzes

    NASA Astrophysics Data System (ADS)

    Buccolieri, Giovanni; Buccolieri, Alessandro; Donati, Paola; Marabelli, Maurizio; Castellano, Alfredo

    2015-01-01

    This paper summarizes the experimental results concerning the Energy Dispersive X-ray Fluorescence (EDXRF) analysis of patinas on two Riace Bronzes, kept in the National Archaeological Museum of Reggio Calabria (Calabria, Southern Italy). The two large Greek sculptures, famous nude bearded warriors both dated in the fifth century BC, are without a doubt, two masterpieces of inestimable historic and artistic value. EDXRF survey had the aim to determinate the chemical composition of the surface of these two bronze statues and to discriminate their different patinas. In particular, the concentration of sulphur, chlorine, tin, manganese, iron, copper, zinc and lead was determined by using a portable apparatus. Multivariate statistical analysis was carried out in order to identify possible correlations and/or differences of elemental composition among the patinas of these two statues. The information obtained made it possible to improve knowledge about the patinas of the Riace Bronzes, and this may help further studies and subsequent methods of restoration and/or of preservation of the two celebrated Greek sculptures.

  9. Effect of Thermally Softened Bronze Matrix on the Fracturing Behavior of Diamond Particles in Hybrid Sprayed Bronze/Diamond Composite

    NASA Astrophysics Data System (ADS)

    Na, Hyuntaek; Bae, Gyuyeol; Kang, Kicheol; Kim, Hyungjun; Kim, Jay-Jung; Lee, Changhee

    2010-09-01

    In our previous study (Na et al., Compos Sci Technol 69:463-468, 2009), optimized thickness of protective nickel film was proposed for smaller diamond feedstock to obtain reduced impact stress and uniform flight behavior of particles during kinetic (or cold) spraying. However, in this study, nickel-coated diamond particles were severely fractured with increasing particle size due to high kinetic energy. Hence, an innovative hybrid spraying technique (a combination of kinetic and thermal spraying) was introduced to embed relatively large diamond particles into the bronze matrix. Size distributions of the diamond particles in the composite coatings were analyzed by scanning electron microscopy, an electron probe micro analyzer, and image analysis methods. In addition, impact behaviors of diamond particles in kinetic and hybrid gas flows were simulated through finite element analysis (ABAQUS/Explicit 6.7-2). Diamond fracturing was significantly minimized by the reduced impact energy afforded by the thermally softened bronze matrix through hybrid spraying.

  10. Mutation of the Light-Induced Yellow Leaf 1 Gene, Which Encodes a Geranylgeranyl Reductase, Affects Chlorophyll Biosynthesis and Light Sensitivity in Rice

    PubMed Central

    Yuan, Yuan; Zhu, Jinyan; Wang, Man; Yuan, Fuhai; Wu, Shujun; Wang, Zhiqin; Yi, Chuandeng; Xu, Tinghua; Ryom, MyongChol; Gu, Minghong; Liang, Guohua

    2013-01-01

    Chlorophylls (Chls) are crucial for capturing light energy for photosynthesis. Although several genes responsible for Chl biosynthesis were characterized in rice (Oryza sativa), the genetic properties of the hydrogenating enzyme involved in the final step of Chl synthesis remain unknown. In this study, we characterized a rice light-induced yellow leaf 1-1 (lyl1-1) mutant that is hypersensitive to high-light and defective in the Chl synthesis. Light-shading experiment suggested that the yellowing of lyl1-1 is light-induced. Map-based cloning of LYL1 revealed that it encodes a geranylgeranyl reductase. The mutation of LYL1 led to the majority of Chl molecules are conjugated with an unsaturated geranylgeraniol side chain. LYL1 is the firstly defined gene involved in the reduction step from Chl-geranylgeranylated (ChlGG) and geranylgeranyl pyrophosphate (GGPP) to Chl-phytol (ChlPhy) and phytyl pyrophosphate (PPP) in rice. LYL1 can be induced by light and suppressed by darkness which is consistent with its potential biological functions. Additionally, the lyl1-1 mutant suffered from severe photooxidative damage and displayed a drastic reduction in the levels of α-tocopherol and photosynthetic proteins. We concluded that LYL1 also plays an important role in response to high-light in rice. PMID:24058671

  11. Resource quality affects weapon and testis size and the ability of these traits to respond to selection in the leaf-footed cactus bug, Narnia femorata.

    PubMed

    Sasson, Daniel A; Munoz, Patricio R; Gezan, Salvador A; Miller, Christine W

    2016-04-01

    The size of weapons and testes can be central to male reproductive success. Yet, the expression of these traits is often extremely variable. Studies are needed that take a more complete organism perspective, investigating the sources of variation in both traits simultaneously and using developmental conditions that mimic those in nature. In this study, we investigated the components of variation in weapon and testis sizes using the leaf-footed cactus bug, Narnia femorata (Hemiptera: Coreidae) on three natural developmental diets. We show that the developmental diet has profound effects on both weapon and testis expression and scaling. Intriguingly, males in the medium-quality diet express large weapons but have relatively tiny testes, suggesting complex allocation decisions. We also find that heritability, evolvability, and additive genetic variation are highest in the high-quality diet for testis and body mass. This result suggests that these traits may have an enhanced ability to respond to selection during a small window of time each year when this diet is available. Taken together, these results illustrate that normal, seasonal fluctuations in the nutritional environment may play a large role in the expression of sexually selected traits and the ability of these traits to respond to selection. PMID:27066225

  12. Climate change conditions (elevated CO2 and temperature) and UV-B radiation affect grapevine (Vitis vinifera cv. Tempranillo) leaf carbon assimilation, altering fruit ripening rates.

    PubMed

    Martínez-Lüscher, J; Morales, F; Sánchez-Díaz, M; Delrot, S; Aguirreolea, J; Gomès, E; Pascual, I

    2015-07-01

    The increase in grape berry ripening rates associated to climate change is a growing concern for wine makers as it rises the alcohol content of the wine. The present work studied the combined effects of elevated CO2, temperature and UV-B radiation on leaf physiology and berry ripening rates. Three doses of UV-B: 0, 5.98, 9.66 kJm(-2)d(-1), and two CO2-temperature regimes: ambient CO2-24/14 °C (day/night) (current situation) and 700 ppm CO2-28/18 °C (climate change) were imposed to grapevine fruit-bearing cuttings from fruit set to maturity under greenhouse-controlled conditions. Photosynthetic performance was always higher under climate change conditions. High levels of UV-B radiation down regulated carbon fixation rates. A transient recovery took place at veraison, through the accumulation of flavonols and the increase of antioxidant enzyme activities. Interacting effects between UV-B and CO2-temperature regimes were observed for the lipid peroxidation, which suggests that UV-B may contribute to palliate the signs of oxidative damage induced under elevated CO2-temperature. Photosynthetic and ripening rates were correlated. Thereby, the hastening effect of climate change conditions on ripening, associated to higher rates of carbon fixation, was attenuated by UV-B radiation. PMID:26025530

  13. Extraction of bioactive compounds and free radical scavenging activity of purple basil (Ocimum basilicum L.) leaf extracts as affected by temperature and time.

    PubMed

    Pedro, Alessandra C; Moreira, Fernanda; Granato, Daniel; Rosso, Neiva D

    2016-05-13

    In the current study, response surface methodology (RSM) was used to assess the effects of extraction time and temperature on the content of bioactive compounds and antioxidant activity of purple basil leaf (Ocimum basilicum L.) extracts. The stability of anthocyanins in relation to temperature, light and copigmentation was also studied. The highest anthocyanin content was 67.40 mg/100 g extracted at 30 °C and 60 min. The degradation of anthocyanins with varying temperatures and in the presence of light followed a first-order kinetics and the activation energy was 44.95 kJ/mol. All the extracts exposed to light showed similar half-lives. The extracts protected from light, in the presence of copigments, showed an increase in half-life from 152.67 h for the control to 856.49 and 923.17 h for extract in the presence of gallic acid and phytic acid, respectively. These results clearly indicate that purple basil is a potential source of stable bioactive compounds. PMID:27192193

  14. Association of tomato leaf curl Sudan virus with leaf curl disease of tomato in Jeddah, Saudi Arabia.

    PubMed

    Sohrab, Sayed Sartaj; Yasir, Muhammad; El-Kafrawy, Sherif Ali; Abbas, Ayman T; Mousa, Magdi Ali Ahmed; Bakhashwain, Ahmed A

    2016-06-01

    Tomato is an important vegetable crop and its production is adversely affected by leaf curl disease caused by begomovirus. Leaf curl disease is a serious concern for tomato crops caused by begomovirus in Jeddah, Kingdom of Saudi Arabia. Tomato leaf curl disease has been shown to be mainly caused either by tomato leaf curl Sudan virus or tomato yellow leaf curl virus as well as tomato leaf curl Oman virus. Many tomato plants infected with monopartite begomoviruses were also found to harbor a symptom enhancing betasatellites. Here we report the association of tomato leaf curl Sudan virus causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia. The complete genome sequence analysis showed highest (99.9 %) identity with tomato leaf curl Sudan virus causing leaf curl disease in Arabian Peninsula. In phylogenetic relationships analysis, the identified virus formed closest cluster with tomato leaf curl Sudan virus. In recombination analysis study, the major parent was identified as tomato leaf curl Sudan virus. Findings of this study strongly supports the associated virus is a variant of tomato leaf curl Sudan virus causing disease in Sudan, Yemen and Arabian Peninsula. The betasatellites sequence analysis showed highest identity (99.8 %) with tomato leaf curl betasatellites-Amaranthus-Jeddah. The phylogenetic analysis result based on betasatellites formed closed cluster with tomato yellow leaf curl Oman betasatellites. The importance of these findings and occurrence of begomovirus in new geographic regions causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia are discussed. PMID:27366765

  15. Earthquake and the Catastrophic End of the Late Bronze Age in the Eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Nur, A.

    2009-04-01

    The reasons for the catastrophic and wide spread political as well as physical collapse in the Aegean and Eastern Mediterranean areas that define the end of the Bronze age ca. 1225 BC to 1175 BC remain a major enigma. It has been attributed by historian to attacks by outsiders with the most favored group being the (enigmatic) so-called sea people. Unfortunately there is no real evidence for this. However combined geological, geophysical and archaeological evidence suggests that earthquakes may have played a key role in this extraordinary collapse during the late 13th and early 12th centuries . Based on the instrumentally recorded earthquakes occurring in the Aegean and Eastern Mediterranean region during the 20th century, several events that have clear historical information, and the geography of seismically active faults it is obvious that numerous earthquakes of magnitude 6·5 or greater (enough to destroy modern buildings, let alone those of antiquity) occurred here frequently in the past. Furthermore major earthquakes often occur in this region in groups, known as ‘‘sequences'' or ‘‘storms'', in which one large quake is followed days, months, or a few years later by others elsewhere on the plate boundary fault lines. When a map of the areas in the Aegean and Eastern Mediterranean region shaken by 20th century  earthquakes of magnitude 6·5 and greater and with an intensity of VII or greater is overlaid on Robert Drews' map of sites destroyed in these same regions during the so-called ‘‘Catastrophe'' near the end of the Late Bronze Age, it is readily apparent that virtually all of these LBA sites lie within the affected (‘‘high-shaking'') areas. This would suggest that a major ‘‘earthquake storm'' may have occurred in the Late Bronze Age Aegean and Eastern Mediterranean during the years 1225-1175 . This ‘‘storm'' may have interacted with societal, political and economic forces at work in these areas c. 1200  and

  16. 48 CFR 252.216-7000 - Economic price adjustment-basic steel, aluminum, brass, bronze, or copper mill products.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-basic steel, aluminum, brass, bronze, or copper mill products. 252.216-7000 Section 252.216-7000 Federal... adjustment—basic steel, aluminum, brass, bronze, or copper mill products. As prescribed in 216.203-4-70(a), use the following clause: Economic Price Adjustment—Basic Steel, Aluminum, Brass, Bronze, or...

  17. 48 CFR 252.216-7000 - Economic price adjustment-basic steel, aluminum, brass, bronze, or copper mill products.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-basic steel, aluminum, brass, bronze, or copper mill products. 252.216-7000 Section 252.216-7000 Federal... adjustment—basic steel, aluminum, brass, bronze, or copper mill products. As prescribed in 216.203-4-70(a), use the following clause: Economic Price Adjustment—Basic Steel, Aluminum, Brass, Bronze, or...

  18. 48 CFR 252.216-7007 - Economic price adjustment-basic steel, aluminum, brass, bronze, or copper mill products...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-basic steel, aluminum, brass, bronze, or copper mill products-representation. 252.216-7007 Section 252....216-7007 Economic price adjustment—basic steel, aluminum, brass, bronze, or copper mill products... Steel, Aluminum, Brass, Bronze, or Copper Mill Products—Representation (MAR 2012) (a) Definitions....

  19. 48 CFR 252.216-7007 - Economic price adjustment-basic steel, aluminum, brass, bronze, or copper mill products...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-basic steel, aluminum, brass, bronze, or copper mill products-representation. 252.216-7007 Section 252....216-7007 Economic price adjustment—basic steel, aluminum, brass, bronze, or copper mill products... Steel, Aluminum, Brass, Bronze, or Copper Mill Products—Representation (MAR 2012) (a) Definitions....

  20. 48 CFR 252.216-7000 - Economic price adjustment-basic steel, aluminum, brass, bronze, or copper mill products.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-basic steel, aluminum, brass, bronze, or copper mill products. 252.216-7000 Section 252.216-7000 Federal... adjustment—basic steel, aluminum, brass, bronze, or copper mill products. As prescribed in 216.203-4-70(a)(1), use the following clause: Economic Price Adjustment—Basic Steel, Aluminum, Brass, Bronze, or...

  1. 48 CFR 252.216-7007 - Economic price adjustment-basic steel, aluminum, brass, bronze, or copper mill products...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-basic steel, aluminum, brass, bronze, or copper mill products-representation. 252.216-7007 Section 252....216-7007 Economic price adjustment—basic steel, aluminum, brass, bronze, or copper mill products... Steel, Aluminum, Brass, Bronze, or Copper Mill Products—Representation (MAR 2012) (a) Definitions....

  2. 48 CFR 252.216-7000 - Economic price adjustment-basic steel, aluminum, brass, bronze, or copper mill products.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-basic steel, aluminum, brass, bronze, or copper mill products. 252.216-7000 Section 252.216-7000 Federal... adjustment—basic steel, aluminum, brass, bronze, or copper mill products. As prescribed in 216.203-4-70(a)(1), use the following clause: Economic Price Adjustment—Basic Steel, Aluminum, Brass, Bronze, or...

  3. 48 CFR 252.216-7000 - Economic price adjustment-basic steel, aluminum, brass, bronze, or copper mill products.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-basic steel, aluminum, brass, bronze, or copper mill products. 252.216-7000 Section 252.216-7000 Federal... adjustment—basic steel, aluminum, brass, bronze, or copper mill products. As prescribed in 216.203-4-70(a)(1), use the following clause: Economic Price Adjustment—Basic Steel, Aluminum, Brass, Bronze, or...

  4. Factors affecting adventitious regeneration from in vitro leaf explants of 'Improved French' plum, the most important dried plum cultivar in the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An adventitious shoot regeneration protocol from leaves of the most important dried plum cultivar in the U.S., 'Improved French', has been established. Factors affecting regeneration were studied, and relatively high percentages have been obtained. The proliferation medium were shoots, used as the...

  5. 7 CFR 51.1814 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false U.S. No. 1 Bronze. 51.1814 Section 51.1814 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Florida Tangerines Grades § 51.1814 U.S. No. 1 Bronze. The requirements for...

  6. 7 CFR 51.684 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false U.S. No. 1 Bronze. 51.684 Section 51.684 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing..., California, and Arizona) Grades § 51.684 U.S. No. 1 Bronze. The requirements for this grade are the same...

  7. 7 CFR 51.684 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false U.S. No. 1 Bronze. 51.684 Section 51.684 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing....684 U.S. No. 1 Bronze. The requirements for this grade are the same as for U.S. No 1 except that...

  8. 7 CFR 51.754 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false U.S. No. 1 Bronze. 51.754 Section 51.754 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Florida Grapefruit Grades § 51.754 U.S. No. 1 Bronze. The requirements for...

  9. 7 CFR 51.754 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false U.S. No. 1 Bronze. 51.754 Section 51.754 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing.... 1 Bronze. The requirements for this grade are the same as for U.S. No. 1 except that at least...

  10. 7 CFR 51.684 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false U.S. No. 1 Bronze. 51.684 Section 51.684 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing....684 U.S. No. 1 Bronze. The requirements for this grade are the same as for U.S. No 1 except that...

  11. 7 CFR 51.623 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false U.S. No. 1 Bronze. 51.623 Section 51.623 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... § 51.623 U.S. No. 1 Bronze. The requirements for this grade are the same as for U.S. No. 1 except...

  12. 7 CFR 51.1814 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false U.S. No. 1 Bronze. 51.1814 Section 51.1814 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Florida Tangerines Grades § 51.1814 U.S. No. 1 Bronze. The requirements for...

  13. 7 CFR 51.684 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false U.S. No. 1 Bronze. 51.684 Section 51.684 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing....684 U.S. No. 1 Bronze. The requirements for this grade are the same as for U.S. No 1 except that...

  14. 7 CFR 51.623 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false U.S. No. 1 Bronze. 51.623 Section 51.623 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... § 51.623 U.S. No. 1 Bronze. The requirements for this grade are the same as for U.S. No. 1 except...

  15. 7 CFR 51.623 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false U.S. No. 1 Bronze. 51.623 Section 51.623 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Florida, California, and Arizona) Grades § 51.623 U.S. No. 1 Bronze. The requirements for this grade...

  16. 7 CFR 51.623 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false U.S. No. 1 Bronze. 51.623 Section 51.623 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... § 51.623 U.S. No. 1 Bronze. The requirements for this grade are the same as for U.S. No. 1 except...

  17. 7 CFR 51.1145 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false U.S. No. 1 Bronze. 51.1145 Section 51.1145 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing....1145 U.S. No. 1 Bronze. The requirements for this grade are the same as for U.S. No. 1 except at...

  18. 7 CFR 51.623 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false U.S. No. 1 Bronze. 51.623 Section 51.623 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Florida, California, and Arizona) Grades § 51.623 U.S. No. 1 Bronze. The requirements for this grade...

  19. 7 CFR 51.1145 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false U.S. No. 1 Bronze. 51.1145 Section 51.1145 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing....1145 U.S. No. 1 Bronze. The requirements for this grade are the same as for U.S. No. 1 except at...

  20. 7 CFR 51.1145 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false U.S. No. 1 Bronze. 51.1145 Section 51.1145 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Florida Oranges and Tangelos Grades § 51.1145 U.S. No. 1 Bronze. The...

  1. 7 CFR 51.1814 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false U.S. No. 1 Bronze. 51.1814 Section 51.1814 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Florida Tangerines Grades § 51.1814 U.S. No. 1 Bronze. The requirements for...

  2. 7 CFR 51.1814 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false U.S. No. 1 Bronze. 51.1814 Section 51.1814 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing.... 1 Bronze. The requirements for this grade are the same as for U.S. No. 1 except that at least...

  3. 7 CFR 51.754 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false U.S. No. 1 Bronze. 51.754 Section 51.754 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Florida Grapefruit Grades § 51.754 U.S. No. 1 Bronze. The requirements for...

  4. 7 CFR 51.754 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false U.S. No. 1 Bronze. 51.754 Section 51.754 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing.... 1 Bronze. The requirements for this grade are the same as for U.S. No. 1 except that at least...

  5. 7 CFR 51.754 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false U.S. No. 1 Bronze. 51.754 Section 51.754 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Florida Grapefruit Grades § 51.754 U.S. No. 1 Bronze. The requirements for...

  6. 7 CFR 51.684 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false U.S. No. 1 Bronze. 51.684 Section 51.684 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing..., California, and Arizona) Grades § 51.684 U.S. No. 1 Bronze. The requirements for this grade are the same...

  7. 7 CFR 51.1814 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false U.S. No. 1 Bronze. 51.1814 Section 51.1814 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing.... 1 Bronze. The requirements for this grade are the same as for U.S. No. 1 except that at least...

  8. 7 CFR 51.1145 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false U.S. No. 1 Bronze. 51.1145 Section 51.1145 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Florida Oranges and Tangelos Grades § 51.1145 U.S. No. 1 Bronze. The...

  9. 7 CFR 51.1145 - U.S. No. 1 Bronze.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false U.S. No. 1 Bronze. 51.1145 Section 51.1145 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Florida Oranges and Tangelos Grades § 51.1145 U.S. No. 1 Bronze. The...

  10. Metallography and microstructure interpretation of some archaeological tin bronze vessels from Iran

    SciTech Connect

    Oudbashi, Omid; Davami, Parviz

    2014-11-15

    Archaeological excavations in western Iran have recently revealed a significant Luristan Bronzes collection from Sangtarashan archaeological site. The site and its bronze collection are dated to Iron Age II/III of western Iran (10th–7th century BC) according to archaeological research. Alloy composition, microstructure and manufacturing technique of some sheet metal vessels are determined to reveal metallurgical processes in western Iran in the first millennium BC. Experimental analyses were carried out using Scanning Electron Microscopy–Energy Dispersive X-ray Spectroscopy and Optical Microscopy/Metallography methods. The results allowed reconstructing the manufacturing process of bronze vessels in Luristan. It proved that the samples have been manufactured with a binary copper–tin alloy with a variable tin content that may relates to the application of an uncontrolled procedure to make bronze alloy (e.g. co-smelting or cementation). The presence of elongated copper sulphide inclusions showed probable use of copper sulphide ores for metal production and smelting. Based on metallographic studies, a cycle of cold working and annealing was used to shape the bronze vessels. - Highlights: • Sangtarashan vessels are made by variable Cu-Sn alloys with some impurities. • Various compositions occurred due to applying uncontrolled smelting methods. • The microstructure represents thermo-mechanical process to shape bronze vessels. • In one case, the annealing didn’t remove the eutectoid remaining from casting. • The characteristics of the bronzes are similar to other Iron Age Luristan Bronzes.

  11. Metallurgical and Chemical Characterization of Bronze Remains Found at the Houhe Site in Shanxi Province, China

    NASA Astrophysics Data System (ADS)

    Mu, D.; Nan, P. H.; Wang, J. Y.; Song, G. D.; Luo, W. G.

    2015-07-01

    This study attempts to determine the metallurgical and chemical characteristics of Chinese bronze artifacts from the early Iron Age by taking the bronze artifacts from the Houhe site as an example. The bronze artifacts included vessels, buckles, mirrors, and bells. Elemental compositions of 10 Chinese bronze artifacts from the Houhe site were determined by an x-ray fluorescence system. Microstructures were observed by a polarizing microscope. Most of the artifacts were cast and lacked external evidence of secondary processing. The copper content of the vessels is higher than the other samples, and the copper content of buckles is the lowest. High tin content is a distinctive characteristic of the mirrors. Through comparisons, bells show a decline in the content of copper from the Western Zhou dynasty to the early Han dynasty, and the content of lead increased over time. Combined with historical studies, the findings show that there may have been industrial standards for bronze production during the Han dynasty.

  12. The study of bronze statuettes with the help of neutron-imaging techniques.

    PubMed

    Van Langh, R; Lehmann, E; Hartmann, S; Kaestner, A; Scholten, F

    2009-12-01

    Until recently fabrication techniques of Renaissance bronzes have been studied only with the naked eye, microscopically, videoscopically and with X-radiography. These techniques provide information on production techniques, yet much important detail remains unclear. As part of an interdisciplinary study of Renaissance bronzes undertaken by the Rijksmuseum Amsterdam, neutron-imaging techniques have been applied with the aim of obtaining a better understanding of bronze workmanship during the Renaissance period. Therefore, an explanation of the fabrication techniques is given to better understand the data collected by these neutron-imaging techniques. The data was used for tomography studies, which reveal hidden aspects that could not at all or scarcely be seen using X-radiography. For this specific study, the representative bronze 'Hercules Pomarius' of Willem van Tetrode (ca 1520-1588) has been examined, along with 20 other Renaissance bronzes from the Rijksmuseum collection. PMID:19756545

  13. Analysis of selective laser cleaning of patina on bronze coins

    NASA Astrophysics Data System (ADS)

    Buccolieri, G.; Nassisi, V.; Torrisi, L.; Buccolieri, A.; Castellano, A.; Di Giulio, M.; Giuffreda, E.; Delle Side, D.; Velardi, L.

    2014-04-01

    The patina, is the result of a large number of chemical, electrochemical and physical processes which occur spontaneously during interaction of metal surfaces with the environment. In this work we want to analyze and remove the patina in artefacts, exposed to atmosphere for various decades. Here, experimental results about the laser cleaning of bronze coins by KrF (248 nm) and Nd:YAG (532 nm) lasers are reported. Both laser wavelengths were efficient to reduce the chlorine concentration on the surface of the coins more than 80 %, as demonstrated by Energy Dispersive X-Ray Fluorescence analyses.

  14. Unified approach for determining tetragonal tungsten bronze crystal structures.

    PubMed

    Smirnov, M; Saint-Grégoire, P

    2014-05-01

    Tetragonal tungsten bronze (TTB) oxides are one of the most important classes of ferroelectrics. Many of these framework structures undergo ferroelastic transformations related to octahedron tilting deformations. Such tilting deformations are closely related to the rigid unit modes (RUMs). This paper discusses the whole set of RUMs in an ideal TTB lattice and possible crystal structures which can emerge owing to the condensation of some of them. Analysis of available experimental data for the TTB-like niobates lends credence to the obtained theoretical predictions. PMID:24815976

  15. Investigation of laser cleaning on bronze cultural relics

    NASA Astrophysics Data System (ADS)

    Ling, Xiulan; Wang, Gao; Zhang, Chen

    2016-05-01

    The effects of laser cleaning on the corrosion layers of bronze cultural relics were studied using a pulsed fiber laser. The laser cleaning threshold value of the corrosion layers was obtained. It was found that the corrosion layer was removed successfully by employing a laser fluence value of 0.32 J cm-2 and scanning for three times. To obtain experimental evidence, laser con-focal scanning microscopy, scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), laser induced breakdown spectroscopy (LIBS) and laser Raman spectroscopy were employed to investigate the cleaning efficiency of corrosion layers on specimens.

  16. Late Bronze Age glass production at Qantir-Piramesses, Egypt.

    PubMed

    Rehren, Thilo; Pusch, Edgar B

    2005-06-17

    It has been uncertain whether the glass produced during the Late Bronze Age (LBA) originated in Egypt or Mesopotamia. Here we present evidence for the production of glass from its raw materials in the eastern Nile Delta during the LBA. Glass was made in workshops that were separate from where the production of objects took place. The initial melting of the raw materials to semi-finished glass was done at temperatures of 900 degrees to 950 degrees C, followed by coloration and ingot production at 1000 degrees to 1100 degrees C. PMID:15961663

  17. Leaf litter decomposition in three Adirondack lakes

    SciTech Connect

    Francis, A.J.; Quinby, H.L.; Hendrey, G.R.; Hoogendyk, C.G.

    1983-04-01

    Decomposition of terrestrial leaf litter in three Adirondack lakes with water pH values approximately 5, 6, and 7 was studied. Litter bags containing leaves of American beech, sugar maple, red maple, leather leaf, and red spruce were placed in the lakes. Samples were removed periodically over a 3-year period and analyzed for loss in weight, changes in leaf surface area, carbon, nitrogen, and bacterial populations. The rate of decomposition of litter depended on the leaf species tested as well as on the lake water in which they were incubated. Of the five leaf species tested, red maple decomposed much faster and red spruce more slowly, i.e., red maple > sugar maple > beech > leather leaf > red spruce. Further, the data indicated that the rate of decomposition of the leaves differed among the lakes in the order Woods (pH approx. 5) < Sagamore (pH approx. 6) < Panther (pH approx. 7), and that the microbial colonization of some leaf species was affected. Accumulations of leaf litter in acid lakes due to reduction in microbial decomposition may affect nutrient recycling in lake ecosystems. 8 references, 4 tables.

  18. Chromatic instabilities in cesium-doped tungsten bronze nanoparticles

    SciTech Connect

    Adachi, Kenji Ota, Yosuke; Tanaka, Hiroyuki; Okada, Mika; Oshimura, Nobumitsu; Tofuku, Atsushi

    2013-11-21

    Nanoparticles of alkali-doped tungsten bronzes are an excellent near-infrared shielding material, but exhibit slight chromatic instabilities typically upon applications of strong ultra-violet light or heating in humid environment, which acts detrimentally to long-life commercial applications. Origin of the chromatic instabilities in cesium-doped tungsten bronze has been investigated, and it has been found that the coloration and bleaching processes comprised electronic exchanges which accelerate or depress the polaron excitation and the localized surface plasmon resonance. Coloration on UV illumination is evidenced by electron diffraction as due to the formation of H{sub x}WO{sub 3}, which is considered to take place in the surface Cs-deficient WO{sub 3} region via the double charge injection mechanism. On the other hand, bleaching on heating in air and in humid environment is shown to accompany the extraction of Cs and electrons from Cs{sub 0.33}WO{sub 3} by X-ray photoelectron spectroscopy and X-ray diffraction analysis and is concluded to be an oxidation of Cs{sub 0.33}WO{sub 3} on the particle surface.

  19. Environmental roots of the late bronze age crisis.

    PubMed

    Kaniewski, David; Van Campo, Elise; Guiot, Joël; Le Burel, Sabine; Otto, Thierry; Baeteman, Cecile

    2013-01-01

    The Late Bronze Age world of the Eastern Mediterranean, a rich linkage of Aegean, Egyptian, Syro-Palestinian, and Hittite civilizations, collapsed famously 3200 years ago and has remained one of the mysteries of the ancient world since the event's retrieval began in the late 19(th) century AD/CE. Iconic Egyptian bas-reliefs and graphic hieroglyphic and cuneiform texts portray the proximate cause of the collapse as the invasions of the "Peoples-of-the-Sea" at the Nile Delta, the Turkish coast, and down into the heartlands of Syria and Palestine where armies clashed, famine-ravaged cities abandoned, and countrysides depopulated. Here we report palaeoclimate data from Cyprus for the Late Bronze Age crisis, alongside a radiocarbon-based chronology integrating both archaeological and palaeoclimate proxies, which reveal the effects of abrupt climate change-driven famine and causal linkage with the Sea People invasions in Cyprus and Syria. The statistical analysis of proximate and ultimate features of the sequential collapse reveals the relationships of climate-driven famine, sea-borne-invasion, region-wide warfare, and politico-economic collapse, in whose wake new societies and new ideologies were created. PMID:23967146

  20. Environmental Roots of the Late Bronze Age Crisis

    PubMed Central

    Kaniewski, David; Van Campo, Elise; Guiot, Joël; Le Burel, Sabine; Otto, Thierry; Baeteman, Cecile

    2013-01-01

    The Late Bronze Age world of the Eastern Mediterranean, a rich linkage of Aegean, Egyptian, Syro-Palestinian, and Hittite civilizations, collapsed famously 3200 years ago and has remained one of the mysteries of the ancient world since the event’s retrieval began in the late 19th century AD/CE. Iconic Egyptian bas-reliefs and graphic hieroglyphic and cuneiform texts portray the proximate cause of the collapse as the invasions of the “Peoples-of-the-Sea” at the Nile Delta, the Turkish coast, and down into the heartlands of Syria and Palestine where armies clashed, famine-ravaged cities abandoned, and countrysides depopulated. Here we report palaeoclimate data from Cyprus for the Late Bronze Age crisis, alongside a radiocarbon-based chronology integrating both archaeological and palaeoclimate proxies, which reveal the effects of abrupt climate change-driven famine and causal linkage with the Sea People invasions in Cyprus and Syria. The statistical analysis of proximate and ultimate features of the sequential collapse reveals the relationships of climate-driven famine, sea-borne-invasion, region-wide warfare, and politico-economic collapse, in whose wake new societies and new ideologies were created. PMID:23967146

  1. Manual HVOF thermal spray repair of nickel aluminum bronze castings

    SciTech Connect

    Brenna, R.T.; McCaw, R.L.; Pugh, J.L.

    1994-12-31

    Manual high velocity oxyfuel (HVOF) thermal spray repairs were accomplished on a large nickel aluminum bronze propeller castings. The repairs were done on three different configurations of surface defects of up to 100 square inches and as deep as 90 mils. Nickel aluminum bronze alloy powder, sieve sized for the HVOF process, was sprayed. High quality, high coating density, repairs were achieved even on porous areas of the castings. Prior to performance of the repairs, a procedure was qualified in accordance with MIL-STD-1687 and a mock-up simulating the repair was produced. After HVOF spraying of the mock-up, the sprayed surface was sanded, milled, and drilled to determine how finishing of the actual castings would be done. After successful procedure qualification, the HVOF equipment was moved to the job site, metal masking was devised for the spray areas and grit blasting and manual HVOF spraying was done. Results of HVOF coating chemical analyses, bend tests, coating tensile bond strength tests, coating microscopic examinations, and mock-up evaluations are reported along with the spray procedures and techniques used in the repairs.

  2. Adult nutrition, but not inbreeding, affects male primary sexual traits in the leaf-footed cactus bug Narnia femorata (Hemiptera: Coreidae).

    PubMed

    Joseph, Paul N; Sasson, Daniel A; Allen, Pablo E; Somjee, Ummat; Miller, Christine W

    2016-07-01

    Adverse conditions may be the norm rather than the exception in natural populations. Many populations experience poor nutrition on a seasonal basis. Further, brief interludes of inbreeding can be common as population density fluctuates and because of habitat fragmentation. Here, we investigated the effects of poor nutrition and inbreeding on traits that can be very important to reproductive success and fitness in males: testes mass, sperm concentration, and sperm viability. Our study species was Narnia femorata, a species introduced to north-central Florida in the 1950s. This species encounters regular, seasonal changes in diet that can have profound phenotypic effects on morphology and behavior. We generated inbred and outbred individuals through a single generation of full-sibling mating or outcrossing, respectively. All juveniles were provided a natural, high-quality diet of Opuntia humifusa cactus cladode with fruit until they reached adulthood. New adult males were put on a high- or low-quality diet for at least 21 days before measurements were taken. As expected, the low-quality diet led to significantly decreased testes mass in both inbred and outbred males, although there were surprisingly no detectable effects on sperm traits. We did not find evidence that inbreeding affected testes mass, sperm concentration, and sperm viability. Our results highlight the immediate and overwhelming effects of nutrition on testes mass, while suggesting that a single generation of inbreeding might not be detrimental for primary sexual traits in this particular population. PMID:27547313

  3. History of a Bronze Age tell and its environment

    NASA Astrophysics Data System (ADS)

    Kovács, Gabriella; Füleky, György; Vicze, Magdolna

    2016-04-01

    Százhalombatta-Földvár is the most excessively researched Bronze Age tell site in Hungary. Parallel to the investigation of the settlement structure and activity patterns the changes of the landscape and the effect of human alteration is also studied. Significant changes of the landscape can be detected from the Bronze Age until the recent natural and cultural heritage protection of the area. Archaeological, soil analytical and thin section soil micromorphological methods are used to reconstruct the past 4000 years of the tell and its immediate surroundings. Prior to the Bronze Age the area was covered by forest vegetation, so the initial settling could only be realised after deforestation (2000 BC). The result of the soil corings and the prepared soil thin sections are solid proves of this action. It also became evident that at some areas - so far it seems that at locales where house floors were laid for the very first time - even the topsoil was removed so intensively that only the B horizon of the relict forest soil can be found. This observation needs to be further tested outside the habitation area to define the horizontal extension of the forest clearance and the topsoil removal. The northern side of the settlement is bordered by a natural erosion gully. At 2000 BC it was just a natural depression, but by 1500 BC it was deepened to serve as a fortification ditch. Around 1200 BC the ditch started to be filled in and by 1000 BC it was refilled to such an extent that its surface was utilised again. At about 600 BC (Late Iron Age) a smaller inner rampart was erected on the southern side of the ditch for inner separation. Not much is known about the Roman period of this area (200 AD) but the remnants of a watchtower indicate their presence. During the 18th century AD the area was used for grape cultivation and later for hobby gardens up until the protection of the area in the late 20th century. Since then species of the original vegetation started to grow back

  4. LAMQS analysis applied to ancient Egyptian bronze coins

    NASA Astrophysics Data System (ADS)

    Torrisi, L.; Caridi, F.; Giuffrida, L.; Torrisi, A.; Mondio, G.; Serafino, T.; Caltabiano, M.; Castrizio, E. D.; Paniz, E.; Salici, A.

    2010-05-01

    Some Egyptian bronze coins, dated VI-VII sec A.D. are analyzed through different physical techniques in order to compare their composition and morphology and to identify their origin and the type of manufacture. The investigations have been performed by using micro-invasive analysis, such as Laser Ablation and Mass Quadrupole Spectrometry (LAMQS), X-ray Fluorescence (XRF), Laser Induced Breakdown Spectroscopy (LIBS), Electronic (SEM) and Optical Microscopy, Surface Profile Analysis (SPA) and density measurements. Results indicate that the coins have a similar bulk composition but significant differences have been evidenced due to different constituents of the patina, bulk alloy composition, isotopic ratios, density and surface morphology. The results are in agreement with the archaeological expectations, indicating that the coins have been produced in two different Egypt sites: Alexandria and Antinoupolis. A group of fake coins produced in Alexandria in the same historical period is also identified.

  5. Coloration and structure of Taiwanese bronze scarab (Anomala expansa)

    NASA Astrophysics Data System (ADS)

    Wu, Min-Nan; Chen, Chien-Yen; Pan, Wei

    2015-12-01

    The structure and optical properties of the elytra of Taiwanese bronze scarabs (Anomala expansa) were investigated. The elytron is composed by a scale-like texture on the surface and a repeated bi-layers underneath. The reflectivity spectrum shows iridescence that the peaks shifts from yellow to green color regions as long as the incident angle (θ) increases. A shoulder peak at 600 nm (θ = 20o) is absent after gently scraping the surface, which indicates that the yellow color is contributed by the scale-like texture. The remaining peak at 550 nm (θ = 20o) in the spectrum resembles the simulated spectrum by assuming the refractive index of n = 1.54 and n = 1 for the adjacent bi-layered structure. This implies that the multi-layered structure contributes to the green coloration as well as the iridescent effect.

  6. Effect of Hydrogen Plasma on Model Corrosion Layers of Bronze

    NASA Astrophysics Data System (ADS)

    Fojtíková, P.; Sázavská, V.; Mika, F.; Krčma, F.

    2016-05-01

    Our work is about plasmachemical reduction of model corrosion layers. The model corrosion layers were produced on bronze samples with size of 10 × 10 × 5 mm3, containing Cu and Sn. Concentrated hydrochloric acid was used as a corrosive environment. The application of reduction process in low-pressure low-temperature hydrogen plasma followed. A quartz cylindrical reactor with two outer copper electrodes was used. Plasma discharge was generated in pure hydrogen by a RF generator. Each corroded sample was treated in different conditions (supplied power and a continual or pulsed regime with a variable duty cycle mode). Process monitoring was ensured by optical emission spectroscopy. After treatment, samples were analyzed by SEM and EDX.

  7. Microstructure characterization of hypereutectoid aluminium bronze composite coating

    NASA Astrophysics Data System (ADS)

    Kucita, P.; Wang, S. C.; Li, W. S.; Cook, R. B.; Starink, M. J.

    2015-10-01

    Hypereutectoid aluminium bronze coating was deposited onto an E.N. 10503 steel substrate using plasma transferred arc welding (PTA). Microstructure characterisation of the coating and a section near the steel substrate joint was carried out using SEM, EBSD, EDS in conjunction with XRD and depth-sensing nano-indentation. The constituent phases in the coating were identified as: martensitic Cu3Al β1' phase, solid solution of Al in Cu α phase and the intermetallic Fe3Al κ1 phase. The region near the steel substrate was characterised by high hardness, large grains and presence of Cu precipitates. No cracks were observed in this region. The coating has high hardness of 4.9GPa and Young's modulus of 121.7GPa. This is attributed to homogeneous distribution of sub microns size Fe3Al intermetallic phase. The implications of the coating to the engineering application of sheet metal forming are discussed.

  8. Microcrystalline sodium tungsten bronze nanowire bundles as efficient visible light-responsive photocatalysts.

    PubMed

    Wang, Lei; Zhan, Jinhua; Fan, Weiliu; Cui, Guanwei; Sun, Honggang; Zhuo, Linhai; Zhao, Xian; Tang, Bo

    2010-12-14

    Microcrystalline sodium tungsten bronze nanowire bundles were obtained via a facile hydrothermal synthesis, and were applied in water purification as visible-light-driven photocatalysts for the first time. PMID:20953497

  9. 46. VIEW OF BRONZE ENGINEERS/INSPECTORS PLAQUE LOCATED ON SOUTH SIDE ...

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

    46. VIEW OF BRONZE ENGINEERS/INSPECTORS PLAQUE LOCATED ON SOUTH SIDE OF WESTERN APPROACH WALL - Tomlinson Bridge, Spanning Quinnipiac River at Forbes Street (U.S. Route 1), New Haven, New Haven County, CT

  10. Growth and ion distribution is affected by irrigation with saline water in selected landscape species grown in two consecutive growing seasons: Spring - Summer and Fall – Winter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Landscape irrigation is the second largest user of reclaimed water in industrialized countries; however its high concentration of soluble salts, especially Na+ and Cl-, may induce growth reduction and leaf necrosis or bronzing in ornamental species. The present study was conducted to determine the g...