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Sample records for ageratum conyzoides leaves

  1. Ageratum conyzoides essential oil as aflatoxin suppressor of Aspergillus flavus.

    PubMed

    Nogueira, Juliana H C; Gonçalez, Edlayne; Galleti, Silvia R; Facanali, Roseane; Marques, Márcia O M; Felício, Joana D

    2010-01-31

    Aflatoxin B(1) (AFB(1)) is a highly toxic and carcinogenic metabolite produced by Aspergillus species on food and agricultural commodities. Inhibitory effects of essential oil of Ageratum conyzoides, on the mycelial growth and aflatoxin B(1) production by Aspergillus flavus were studied. Cultures were incubated in yeast extract-sucrose (YES) broth for days at 25 degrees C at the following different concentrations of the essential oil (from 0.0 to 30mug/mL). The essential oil inhibited fungal growth to different extents depending on the concentration, and completely inhibited aflatoxin production at concentrations above 0.10microg/mL. The analysis of the oil by GC/MS showed that its main components are precocene II (46.35%), precocene I (42.78%), cumarine (5.01%) and Trans-caryophyllene (3.02%). Comparison by transmission electron microscopy of the fungal cells, control and those incubated with different concentrations of essential oil, showed ultra-structural changes which were concentration dependent of the essential oil of A. conyzoides. Such ultra-structural changes were more evident in the endomembrane system, affecting mainly the mitochondria. Degradation was also observed in both surrounding fibrils. The ability to inhibit aflatoxin production as a new biological activity of A.conyzoides L. indicates that it may be considered as a useful tool for a better understanding of the complex pathway of aflatoxin biosynthesis.

  2. A comparative study of the wound healing properties of honey and Ageratum conyzoides.

    PubMed

    Oladejo, O W; Imosemi, I O; Osuagwu, F C; Oyedele, O O; Oluwadara, O O; Ekpo, O E; Aiku, A; Adewoyin, O; Akang, E E U

    2003-06-01

    The present study investigates the wound healing properties of methanolic extracts of Ageratum conyzoides leaves compared with those of honey. Thirty Wistar rats were randomized into 3 groups of 10 animals each. They were fed with standard rat cubes and Tap water weighed and acclimatized to laboratory conditions for one week. Under anesthesia, each animal had the skin of its dorsolateral flank shaved after which an area of the skin was excised. On achieving haemostasis, the wounds were packed with gauze soaked in the appropriate dressing for each group. Measurement of wound size, and wound biopsies were taken on the 10th day post-wound creation. Together with healed wound samples, these were processed for histology. Fibroblast and blood vessel densities per unit area of wound were determined for the healed wound samples. Histologically, the day 10 Ageratum sections showed fewer inflammatory cells compared with similar honey and Control sections. Also, healed scar sections of wounds dressed with the herb extract showed more fibrosis. Honey and Ageratum caused significant greater wound contraction than controls (p = 0.001 and 0.005 respectively). Healed wounds from the Ageratum group had significantly fewer fibroblasts than honey and controls (p = 0.012 and 0.036 respectively).

  3. Ageratum conyzoides: a host to a unique begomovirus disease complex in Cameroon.

    PubMed

    Leke, Walter N; Brown, Judith K; Ligthart, Maaike E; Sattar, Naaem; Njualem, Dominic K; Kvarnheden, Anders

    2012-01-01

    Ageratum conyzoides (goat weed) is a widespread uncultivated species in Cameroon that exhibits leaf curl disease (LCD) symptoms suggestive of begomovirus infection. In Asia, different begomovirus-satellite complexes have been identified in A. conyzoides. The objective of this study was to determine the identity of the suspect begomoviruses and their associated satellites in A. conyzoides in Cameroon. The results indicated that all three symptomatic A. conyzoides plants examined were infected with a new begomovirus species, herein named Ageratum leaf curl Cameroon virus (ALCCMV). The ALCCMV genome sequences shared their highest identity, at 84.3-88.5%, with a group of tomato-infecting begomoviruses from West Africa. In addition, a betasatellite and an alphasatellite were cloned from the same symptomatic A. conyzoides plants. The betasatellite sequences shared limited sequence identity at 37% or less with the betasatellite Cotton leaf curl Gezira betasatellite, and the new betasatellite species is herein named Ageratum leaf curl Cameroon betasatellite (ALCCMB). The alphasatellite shared 80% nt identity with Tomato leaf curl Cameroon alphasatellite (ToLCCMA), and the new alphasatellite species is herein named Ageratum leaf curl Cameroon alphasatellite (ALCCMA). In addition, two fragments containing begomovirus-alphasatellite sequences were cloned from sample AGLI4, and they were related to the defecting interfering molecule (Y14167) associated with Ageratum yellow vein virus from Asia. These results suggest that the begomoviral-satellite complexes infecting A. conyzoides in Cameroon may be as complex or more so, to species and strains reported thus far from Asia.

  4. Removal of methylene blue from dye effluent using ageratum conyzoide leaf powder (ACLP)

    NASA Astrophysics Data System (ADS)

    Ezechi, Ezerie Henry; Kutty, Shamsul Rahman bin Mohamed; Malakahmad, Amirhossein; Isa, Mohamed Hasnain; Aminu, Nasiru; Salihi, Ibrahim Umar

    2015-07-01

    Methylene blue (MB), a common environmental pollutant discharged from dye effluents were removed from synthetic effluents in this study using ageratum conyzoide leaf powder. Effects of operating parameters such as pH, initial Methylene blue concentration, adsorbent weight and contact time were examined on methylene blue removal whereas stirring speed was constant at 100 rpm. Results show that low pH (3-4) had more Methylene blue removal than high pH. Methylene blue removal decreased when initial concentration was increased but increased when adsorbent weight was increased. Removal of Methylene blue by Ageratum conyzoide leaf powder was rapid and significantly above 80% in all initial concentrations examined. At optimum conditions of pH 3, 20 minutes contact time and adsorbent weight of 60 mg for Methylene blue initial concentration of 20 mg/L, 40 mg/L and 60 mg/L, Methylene blue removal of 84.7%, 83.9% and 81.2% were obtained respectively. Results suggest that Ageratum conyzoide leaf powder could be potential adsorbents for Methylene blue removal from dye effluents.

  5. Volatile oils from the plant and hairy root cultures of Ageratum conyzoides L.

    PubMed

    Abdelkader, Mohamed Salaheldin A; Lockwood, George B

    2011-05-01

    Two lines of hairy root culture of Ageratum conyzoides L. induced by Agrobacterium rhizogenes ATCC 15834 were established under either complete darkness or 16 h light/8 h dark photoperiod conditions. The volatile oil yields from aerial parts and roots of the parent plant, the hairy root culture photoperiod line and the hairy root culture dark line were 0.2%, 0.08%, 0.03% and 0.02%, (w/w), respectively. The compositions of the volatiles from the hairy roots, plant roots and aerial parts were analysed by GC and GC-MS. The main components of the volatiles from the hairy root cultures were β-farnesene, precocene I and β-caryophyllene, in different amounts, depending on light conditions and also on the age of cultures. Precocene I, β-farnesene, precocene II and β-caryophyllene were the main constituents of the volatile oils from the parent plant roots, whereas precocene I, germacrene D, β-caryophyllene and precocene II were the main constituents of the aerial parts of the parent plant. Growth and time-course studies of volatile constituents of the two hairy root lines were compared. Qualitative and quantitative differences were found between the volatile oils from the roots of the parent plant and those from the hairy roots.

  6. Acute Sodium Arsenite-Induced Hematological and Biochemical Changes in Wistar Rats: Protective Effects of Ethanol Extract of Ageratum conyzoides

    PubMed Central

    Ola-Davies, Olufunke Eunice; Akinrinde, Akinleye Stephen

    2016-01-01

    Background: Ageratum conyzoides L. (Asteraceae) is an annual herbaceous plant used in folklore medicine for the treatment of a wide range of diseases. Objective: To investigate the protective effect of the ethanol leaf extract of A. conyzoides (EEAC) against hematological, serum biochemical and histological alterations induced by Sodium arsenite administration to Wistar rats. Materials and Methods: Twenty male Wistar rats were randomly assigned into four groups of five rats each. Group I received propylene glycol and Group II rats were given the (EEAC, 100 mg/kg b.w.) orally for 7 days. Group III were given a single oral dose of sodium arsenite (NaAsO2, 2.5 mg/kg b.w.). Animals in Group IV were pretreated with 100 mg/kg EEAC for 7 days followed by a single oral dose of sodium arsenite. Results: Arsenic exposure resulted in significant reductions (P < 0.05) in values of packed cell volume (PCV), hemoglobin concentration (Hb) and red blood cell (RBC) count, and elevation in total white blood cell (WBC) count with insignificant reductions in serum total protein, albumin, and globulin levels. Alterations in aspartate aminotransferase, alanine transferase, alkaline phosphatase, and gamma glutamyl transferase activities, as well as in serum levels of urea, creatinine, glucose, cholesterol, and triglyceride levels, were not statistically significant. EEAC significantly restored (P < 0.05) the PCV, Hb, RBC, and WBC as well as serum albumin, globulin, and total protein to normal values. Conclusion: The results of this study indicate that EEAC possess strong potentials to protect against toxicities induced by sodium arsenite. SUMMARY Ageratum conyzoides produced significant reversal of the reduction in the erythrocytic indices (packed cell volume, red blood cell, and Hb) caused by sodium arseniteSodium arsenite-induced slight elevations in serum aspartate aminotransferase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP), correlating with the

  7. Evaluation of quality and efficacy of an ethnomedicinal plant Ageratum conyzoides L. in the management of pediculosis

    PubMed Central

    Shailajan, Sunita; Wadke, Priyanka; Joshi, Harshvardhan; Tiwari, Bhavesh

    2013-01-01

    Background Infestation with the head louse, Pediculus humanus capitis, is one of the most common parasitic infestations of human worldwide. Traditionally, the main treatment for control of head lice is chemical control that includes wide variety of neurotoxic synthetic insecticides. The main difficulty posed in controlling the head louse infestation is increasing lice resistance to synthetic pediculicidal drugs. Plant-based drugs; especially essential oil components and standardized extracts have been suggested as an alternative source of materials for insect control. Ageratum conyzoides L. (Asteraceae) has been reported to possess antifungal and insecticidal properties. In the present research work, an attempt has been made to evaluate in vitro pediculicidal activity of A. conyzoides. Methods A filter paper diffusion bioassay was carried out in order to determine the pediculicidal activity of different extracts of A. conyzoides. Results The study elucidates the active plant part and suitable extract responsible for the therapeutic efficacy of this plant in the management of pediculosis. Conclusion Findings of the present study indicate the potential of A. conyzoides extract to be included in the formulations as a pediculicidal agent. PMID:24563592

  8. Do Aloe vera and Ageratum conyzoides enhance the anti-microbial activity of traditional medicinal soft soaps (Osedudu)?

    PubMed

    Moody, J O; Adebiyi, O A; Adeniyi, B A

    2004-05-01

    The Nigerian traditional soft soaps prepared using varied locally sourced raw materials such as cocoa pod ash (Theobroma cacao) palm kernel shaft ash (Elaies guineensis) have been evaluated for their physico-chemical properties and anti-microbial activities using standard pharmacopoeia protocols and an in-vitro agar diffusion bioassay method. The anti-microbial evaluation was done with and without incorporation of Aloe vera and Ageratum conyzoides extractives into the soap samples. Results showed that the physico-chemical properties of the soaps are dependent on the raw materials utilised. The incorporated medicinal plants used in this study, however, did not show any significant effect on the anti-microbial activities exhibited by the various soaps against the bacterial and fungal test organisms.

  9. Insecticidal activity of Ageratum conyzoides L., Coleus aromaticus Benth. and Hyptis suaveolens (L.) Poit essential oils as fumigant against storage grain insect Tribolium castaneum Herbst.

    PubMed

    Jaya; Singh, Priyanka; Prakash, Bhanu; Dubey, N K

    2014-09-01

    Essential oils (EOs) from Ageratum conyzoides L., Coleus aromaticus Benth. and Hyptis suaveolens (L.) Poit were extracted and tested against Tribolium castaneum Herbst, the storage grain insect. The EOs were found effective against Tribolium castaneum during in vitro as well as in vivo fumigant testing. The EOs of H. suaveolens and A. conyzoides showed 100 % mortality of test insect at 250 ppm while C. aromaticus at 350 ppm. During in vivo fumigant testing of wheat samples against Tribolium castaneum, the essential oils of A. conyzoides and C. aromaticus completely checked the damage of wheat grains by the insect at 1000 ppm while essential oil of H. suaveolens checked the grain damage completely even at 500 ppm concentration. There was no adverse effect on seed germination as well as on seedling growth of EOs treated seeds showing non-phytotoxic nature of the oils. Hence, these EOs may be recommended as botanical insecticide against insect invasion of stored food commodities, thereby enhancing their shelf life.

  10. Isolation, partial purification and evaluation of bioactive compounds from leaves of Ageratum houstonianum

    PubMed Central

    Zeeshan, M.; Rizvi, S.M.D.; Khan, M.S.; Kumar, A.

    2012-01-01

    The present study deals with the isolation and partial purification of bioactive compounds from the crude methanol extracts of the leaves of Ageratum houstonianum (Asteraceae). The quantification and the identification of compounds in the crude extract and active bands isolated by preparative TLC were accomplished using GC-MS analysis. The most important compounds identified in the crude extract and active bands (AB-1 and AB-2) were 6-acetyl-7-methoxy-2, 2-dimethylchromene, hexadecanoic acid and squalene, respectively. Crude extract and active bands (AB-1 and AB-2) were investigated for their antibacterial activity against Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The crude extract, AB-1 and AB-2 showed maximum zone of inhibition (10-13 mm) against Staphylococcus epidermidis, however, the antibacterial potential of active bands was slightly higher as compared to the crude extract. Dose-dependant increase in antioxidant potential was noticed in crude extract as well as with both active bands measured by DPPH free radicals, ion chelation and total antioxidants capacity. Our study reports various bioactive compounds in the leaves of the A. houstonianum with significant antioxidant and antibacterial potential. PMID:27350770

  11. A study of the acaricidal properties of an essential oil extracted from the leaves of Ageratum houstonianum.

    PubMed

    Tedonkeng Pamo, E; Tendonkeng, F; Kana, J R; Khan Payne, V; Boukila, B; Lemoufouet, J; Miegoue, E; Nanda, A S

    2005-03-31

    Study on acaricide property of foam soap containing essential oil of Ageratum houstonianum leaves was tested on Rhipicephalus lunulatus. Four doses of the oil (0.00, 0.02, 0.025 and 0.03 microl/g) with four replications for each dose were used in vitro. Each replication consisted of 10 ticks in a Petri dish with filter paper impregnated uniformly with the foam soap on the bottom. The same four doses in three replications were used in vivo. Each replication was made up of 10 naturally ticks infested goats. Results of this study indicate that foam soap containing essential oil of A. houstonianum leaves is toxic to R. lunulatus. The in vitro mortality rate was observed to vary from 0 to 50% on day 8 after treatment with the controls as compared to 95% with the lowest dose (0.02 microl/g) on day 8 and 100% with the highest dose (0.03 microl/g) on day 3. Meanwhile, the in vivo mortality rate was observed to be 23.4% with the control on day 8 after treatment whereas the highest dose killed 95.1% of the ticks by this day. The LD50 of the foam soap containing essential oil of this plant was 0.0259 and 0.0173 microl/g on day 2 after treatment, in the laboratory and on the farm, respectively. This indicates a potentially high efficiency of this medicated soap on this parasite.

  12. A begomovirus associated with Ageratum yellow vein disease in Indonesia: evidence for natural recombination between tomato leaf curl Java virus and Ageratum yellow vein virus-[Java].

    PubMed

    Kon, T; Kuwabara, K; Hidayat, S H; Ikegami, M

    2007-01-01

    A begomovirus (2747 nucleotides) and a satellite DNA beta component (1360 nucleotides) have been isolated from Ageratum conyzoides L. plants with yellow vein symptoms growing in Java, Indonesia. The begomovirus is most closely related to Tomato leaf curl Java virus (ToLCJV) (91 and 98% in the total nucleotide and coat protein amino acid sequences, respectively), although the products of ORFs C1 and C4 are more closely related to those of Ageratum yellow vein virus-[Java] (91 and 95% identity, respectively). For this reason, the begomovirus it is considered to be a strain of ToLCJV and is referred to as ToLCJV-Ageratum. The virus probably derives from a recombination event in which nucleotides 2389-2692 of ToLCJV have been replaced with the corresponding region of the AYVV-[Java] genome, which includes the 5' part of the intergenic region and the C1 and C4 ORFs. Infection of A. conyzoides with ToLCJV-Ageratum alone produced no symptoms, but co-infection with DNAbeta induced yellow vein symptoms. Symptoms induced in Nicotiana benthamiana by ToLCJV-Ageratum, ToLCJV and AYVV-[Java] are consistent with the exchange of pathogenicity determinant ORF C4 during recombination.

  13. An enzoinformatics study targeting polo-like kinases-1 enzyme: Comparative assessment of anticancer potential of compounds isolated from leaves of Ageratum houstonianum

    PubMed Central

    Rizvi, Syed Mohd. Danish; Shakil, Shazi; Zeeshan, Mohd.; Khan, Mohd. Sajid; Shaikh, Sibhghatulla; Biswas, Deboshree; Ahmad, Adnan; Kamal, Mohammad Amjad

    2014-01-01

    Natural products from plant sources, embracing inherently ample structural diversity than synthetic ones are the major sources of anticancer agents and will constantly play as protagonists for discovering new drugs. Polo-like kinases (PLKs) play a leading role in the ordered execution of mitotic events and 4 mammalian PLK family members have been identified. PLK1 is an attractive target for anticancer drugs in mammalian cells, among the four members of PLKs. The present study expresses the molecular interaction of compounds (1,2-Benzenedicarboxylic acid bis (2 ethylhexyl) ester, squalene, 3,5-bis (1,1-dimethylethyl) phenol, Pentamethyl tetrahydro-5H-chromene, (1,4-Cyclohexylphenyl) ethanone and 6-Vinyl-7-methoxy-2,2-dimethylchromene) isolated from methanolic extract of leaves of Ageratum houstonianum with PLK1 enzyme. Docking between PLK1 and each of these compounds (separately) was performed using “Auto dock 4.2.” (1,4-Cyclohexylphenyl) ethanone showed the maximum potential as a promising inhibitor of PLK1 enzyme with reference to ∆G (−6.84 kcal/mol) and Ki (9.77 μM) values. This was sequentially followed by Pentamethyl tetrahydro-5H-chromene (∆G = −6.60 kcal/mol; Ki = 14.58 μM), squalene (∆G = −6.17 kcal/mol; Ki = 30.12 μM), 6-Vinyl-7-methoxy-2,2-dimethylchromene (∆G = −5.91 kcal/mol; Ki = 46.68 μM), 3, 5-bis (1,1-dimethylethyl) phenol (∆G = −5.70 kcal/mol; Ki = 66.68 μM) and 1,2-Benzenedicarboxylic acid bis (2 ethylhexyl) ester (∆G = −5.58 kcal/mol; Ki = 80.80 μM). These results suggest that (1,4-Cyclohexylphenyl) ethanone might be a potent PLK1 inhibitor. Further, in vitro and in vivo rumination are warranted to validate the anticancer potential of (1,4-Cyclohexylphenyl) ethanone. PMID:24914294

  14. Ageratum enation virus-a begomovirus of weeds with the potential to infect crops.

    PubMed

    Tahir, Muhammad; Amin, Imran; Haider, Muhammad Saleem; Mansoor, Shahid; Briddon, Rob W

    2015-02-10

    Samples of two Ageratum conyzoides, one Sonchus oleraceus and one turnip (Brassica rapa var. rapa) exhibiting virus-like symptoms were collected from Pakistan and Nepal. Full-length begomovirus clones were obtained from the four plant samples and betasatellite clones from three of these. The begomovirus sequences were shown to be isolates of Ageratum enation virus (AEV) with greater than 89.1% nucleotide sequence identity to the 26 AEV sequences available in the databases. The three betasatellite sequences were shown to be isolates of Ageratum yellow leaf curl betasatellite (AYLCB) with greater than 90% identity to the 18 AYLCB sequences available in the databases. The AEV sequences were shown to fall into two distinct strains, for which the names Nepal (consisting of isolates from Nepal, India, and Pakistan-including the isolates identified here) and India (isolates occurring only in India) strains are proposed. For the clones obtained from two AEV isolates, with their AYLCB, infectivity was shown by Agrobacterium-mediated inoculation to Nicotiana benthamiana, N. tabacum, Solanum lycopersicon and A. conyzoides. N. benthamiana plants infected with AEV alone or betasatellite alone showed no symptoms. N. benthamiana plants infected with AEV with its associated betasatellite showed leaf curl symptoms. The findings show that AEV is predominantly a virus of weeds that has the capacity to infect crops. AYLCB appears to be the common partner betasatellite of AEV and is associated with diseases with a range of very different symptoms in the same plant species. The inability to satisfy Koch's postulates with the cloned components of isolate SOL in A. conyzoides suggests that the etiology may be more complex than a single virus with a single betasatellite.

  15. Ageratum enation virus—A Begomovirus of Weeds with the Potential to Infect Crops

    PubMed Central

    Tahir, Muhammad; Amin, Imran; Haider, Muhammad Saleem; Mansoor, Shahid; Briddon, Rob W.

    2015-01-01

    Samples of two Ageratum conyzoides, one Sonchus oleraceus and one turnip (Brassica rapa var. rapa) exhibiting virus-like symptoms were collected from Pakistan and Nepal. Full-length begomovirus clones were obtained from the four plant samples and betasatellite clones from three of these. The begomovirus sequences were shown to be isolates of Ageratum enation virus (AEV) with greater than 89.1% nucleotide sequence identity to the 26 AEV sequences available in the databases. The three betasatellite sequences were shown to be isolates of Ageratum yellow leaf curl betasatellite (AYLCB) with greater than 90% identity to the 18 AYLCB sequences available in the databases. The AEV sequences were shown to fall into two distinct strains, for which the names Nepal (consisting of isolates from Nepal, India, and Pakistan—including the isolates identified here) and India (isolates occurring only in India) strains are proposed. For the clones obtained from two AEV isolates, with their AYLCB, infectivity was shown by Agrobacterium-mediated inoculation to Nicotiana benthamiana, N. tabacum, Solanum lycopersicon and A. conyzoides. N. benthamiana plants infected with AEV alone or betasatellite alone showed no symptoms. N. benthamiana plants infected with AEV with its associated betasatellite showed leaf curl symptoms. The findings show that AEV is predominantly a virus of weeds that has the capacity to infect crops. AYLCB appears to be the common partner betasatellite of AEV and is associated with diseases with a range of very different symptoms in the same plant species. The inability to satisfy Koch’s postulates with the cloned components of isolate SOL in A. conyzoides suggests that the etiology may be more complex than a single virus with a single betasatellite. PMID:25674770

  16. Buffalo calves intoxicated with Ageratum houstonianum mill

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ageratum houstonianum Mill, a noxious weed has been reported to contain pyrrolizidine alkaloids, saponins, triterpens and coumarin. It is an invasive weed that is commonly found in the pasturelands of tropical and subtropical regions. The objectives of this work were to verify the toxicity of A. ho...

  17. Antimony accumulation in Achillea ageratum, Plantago lanceolata and Silene vulgaris growing in an old Sb-mining area.

    PubMed

    Baroni, F; Boscagli, A; Protano, G; Riccobono, F

    2000-08-01

    Preliminary data of a biogeochemical survey concerning antimony transfer from soil to plants in an abandoned Sb-mining area are presented. Achillea ageratum, Plantago lanceolata and Silene vulgaris can strongly accumulate antimony when its extractable fraction in the soil is high (139-793 mg/kg). A. ageratum accumulates in basal leaves (1367 mg/kg) and inflorescences (1105 mg/kg), P. lanceolata in roots (1150 mg/kg) and S. vulgaris in shoots (1164 mg/kg). In these plant species, the efficiency of antimony accumulation decreases when the antimony availability in the soil is high. In A. ageratum and S. vulgaris, the death of the epigeal target part at the end of the growing season contributes to a reduction of the antimony load in the plant. A study to test the use of these species as bioindicators of antimony availability in soil is suggested by our results.

  18. Essential oil composition and antimicrobial activity of wild and cultivated Moroccan Achillea ageratum L.: a rare and threatened medicinal species.

    PubMed

    El Bouzidi, Laila; Abbad, Abdelaziz; Hassani, Lahcen; Fattarsi, Karine; Leach, David; Markouk, Mohammed; Legendre, Laurent; Bekkouche, Khalid

    2012-03-01

    The essential oils of leaves and flowers of the wild and cultivated Moroccan Achillea ageratum L., a rare and threatened medicinal species, were examined by GC/MS, and their chemical compositions were compared. At least nine components were identified in both wild and cultivated A. ageratum oils, representing more than 95% of the oils. Artemisyl acetate (62.34-78.79%), yomogi alcohol (4.89-12.40%), santolina alcohol (4.86-11.77%), and artemisia alcohol (3.36-7.04%) were the major compounds. Terpene-alcohol proportion was higher in wild A. ageratum than in cultivated A. ageratum. The antibacterial analysis showed that both oils presented high activity against all the studied Gram-positive strains in a range of MIC values from 2.55 to 7.02 mg/ml, but they appeared not effective against the tested Gram-negative ones (MIC values 20.40-41.10 mg/ml). They also exhibited remarkable antifungal activities against Candida species with MIC values ranging from 5.83 to 8.42 mg/ml. From these results, it was concluded that domestication of this threatened medicinal species using clonal propagation did not significantly affect its chemical composition and consequently its antimicrobial properties.

  19. Ageratum houstonianum toxicosis in zebu cattle.

    PubMed

    Noa, Mario; Sánchez, Luz María; Durand, Reina

    2004-08-01

    Ageratum houstonianum (Ageratum, flossflower, blue billygoat weed) is an annual plant that tends to become a pest in gardens and pastures. Clinical signs for A. houstonianum toxicosis in cattle are characterized by either an acute hemorrhagic course or sub-acute photodynamic dermatitis. The toxicosis has often been associated with Holstein-Friesian or crossbreed Holstein cattle less resistant to tropical climate conditions. During a recent especially dry spring about 40 adult Zebu cattle were found dead, while another 40/800 animals were sacrificed. The animals had been relocated to the problem area about 4 mo before, where due to the prolonged drought, A. houstonianum was almost exclusively the only pasture available. The intoxicated cattle did not show the characteristic toxic dermatitis reported for A. houstonianum acute toxicosis; but post-mortem examination revealed bloody serous fluid in coccyx-femoral joints and hemorrhages in the large muscle tissues, while liver, kidney and heart also had hemorrhages. To confirm the toxic plant as cause of the toxicosis, phytochemical Qualitative screening and a novel thin-layer chromatographic characterization of plant extracts were done. The chromatographic profiles of coumarin compounds, alkaloids and triterpens in ruminal and intestinal contents were similar to those obtained from A. houstonianum plants from the same area, confirming ingestion of A. houstonianum as cause of the toxicosis. The coincidence of adverse nutritional conditions together with the cattle's ignorance of the grazing area predisposed the plant toxicosis.

  20. Leaving

    ERIC Educational Resources Information Center

    Jones, Robyn L.

    2011-01-01

    Within this article, the author presents a personal story, "Leaving," which highlights the problematic experience of opposing established practice. The tale tells of the difficulty faced by creative agency when confronted by a constraining structural hegemony. Specifically, it draws attention to the professionalization of academic life through a…

  1. Mixed infection by two West African tomato-infecting begomoviruses and ageratum leaf curl Cameroon betasatellite in tomato in Cameroon.

    PubMed

    Leke, Walter N; Kvarnheden, Anders

    2014-11-01

    Begomovirus isolates ToF3B2 and ToF3B17 and betasatellite isolate SatBToF3 were obtained from the same infected tomato plant showing begomovirus disease symptoms in Fontem, Cameroon. The full-length nucleotide sequences of ToF3B2, ToF3B17 and SatBToF3 were cloned and sequenced and were determined to be 2,797 nt, 2,794 and 1,373 nt long respectively. When compared with other begomovirus and betasatellite sequences, ToF3B2 was 93.5 % identical to Tomato leaf curl Togo virus, ToF3B17 was 95 % identical to Tomato leaf curl Cameroon virus and SatBToF3 was 92 % identical to Ageratum leaf curl Cameroon betasatellite (ALCCMB), respectively. The identification of ALCCMB in Ageratum and now in tomato strongly suggests Ageratum may be an alternative host to these viruses and that ALCCMB is non host specific and may cause severe diseases when transmitted to other crops.

  2. Chemical composition and antibacterial activity of essential oils of Lantana camara, Ageratum houstonianum and Eupatorium adenophorum.

    PubMed

    Kurade, Nitin P; Jaitak, Vikas; Kaul, Vijay K; Sharma, Om P

    2010-05-01

    Essential oils have applications in folk medicine, food preservation, and as feed additives. The essential oils of Lantana camara Linn. (Verbenaceae), Ageratum houstonianum Mill. (Asteraceae) and Eupatorium adenophorum Spreng. (Asteraceae) were analyzed by Gas chromatography-mass spectrometry (GCMS). In L. camara oil, of the total identified (83.91%) volatile constituents, five constituents [3,7,11-trimethyl-1,6,10-dodecatriene (28.86%), beta-caryophyllene (12.28%), zingiberene (7.63%), gamma-curcumene (7.50%) and alpha-humulene (3.99%)] represented the major ones. In A. houstonianum oil, among the total identified volatile constituents (94.51%), three [precocene-II (52.64%), precocene-I (22.45%) and beta-caryophyllene (9.66%)] represented the major ones. In E. adenophorum oil, of the total identified volatile constituents (84.95%), six [1-napthalenol (17.50%), alpha-bisabolol (9.53%), bornyl acetate (8.98%), beta-bisabolene (6.16%), germacrene-D (5.74%) and alpha- phellandrene (3.85%)] represented the major ones. The antibacterial activity expressed as Minimum Bactericidal Concentration (MBC) (microg/mL) was determined by the broth dilution method. The essential oil of E. adenophorum had antibacterial activity against Arthrobacter protophormiae, Escherichia coli, Micrococcus luteus, Rhodococcus rhodochrous, and Staphylococcus aureus with MBC values of 200, 100, 100, 12.5, and 200, respectively. The essential oil of A. houstonianum showed antibacterial activity against M. luteus and R. rhodochrous with MBC of 100 and 12.5, but not against A. protophormiae, E. coli, and S. aureus. The essential oil of L. camara showed antibacterial activity against A. protophormiae, M. luteus, R. rhodochrous and S. aureus with MBC of 50, 25, 12.5, and 200, respectively, but not against E. coli. MBC was lowest for R. rhodochrous for all the three essential oils.

  3. Effect of Ageratum houstonianum Mill. (Asteraceae) leaf extracts on the oviposition activity of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae).

    PubMed

    Tennyson, Samuel; Ravindran, K John; Eapen, Alex; William, S John

    2012-12-01

    Plant extracts have been studied extensively for their insecticidal activity against immature stages and adult mosquitoes. They have also been reported to influence the habitat preference of ovipositing mosquitoes. Ageratum houstonianum, a medicinal plant belonging to the family Asteraceae, has been reported to possess insecticidal activity, and in the present study, the ovipositional attractant/deterrent activity was studied. The effect of Ageratum houstonianum crude leaf extracts on the oviposition of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus was studied at 0.1 % concentration in laboratory. Among hexane, ethyl acetate and methanol crude leaf extracts, methanol showed an effective deterrent activity against all the three vector species with an oviposition active index of -0.8, -0.8 and -0.9, respectively. Field trials carried out to study the effect of 0.1 % methanol extract on oviposition of Aedes species indicated effective deterrence ranging from 79.0 to 100.0 % in indoor and 74.6 to 100.0 % in outdoor ovitraps. The potential oviposition deterrent property of Ageratum houstonianum crude leaf extracts observed in both laboratory and field studies indicates the presence of phytocompounds that act as effective contact deterrent. Further, isolation, identification and preparation of suitable formulation of the effective phytocompounds of Ageratum houstonianum that act as a contact deterrent are required.

  4. Molecular identification of Ageratum enation virus, betasatellite and alphasatellite molecules isolated from yellow vein diseased Amaranthus cruentus in India.

    PubMed

    Srivastava, Ashish; Raj, Shri Krishana; Kumar, Susheel; Snehi, Sunil Kumar; Kulshreshtha, Aditya; Hallan, Vipin; Pande, Sunil Sohanlal

    2013-12-01

    Natural occurrence of yellow vein disease on Amaranthus cruentus was observed at Lucknow, India in the year 2008. The causal virus was successfully transmitted through whiteflies (Bemisia tabaci) from diseased A. cruentus to healthy seedlings of A. cruentus and other test species which indicated begomovirus infection. The begomovirus DNA-A, betasatellite, and alphasatellite components associated with yellow vein disease were amplified by rolling circle amplification using Ø-29 DNA polymerase from diseased A. cruentus and characterized by their sequence analyses. The begomovirus DNA-A genome contained six ORFs: AV2 and AV1 in virion sense and AC3, AC2, AC1, and AC4 in complementary sense strand; and a non-translated intergenic region having the conserved geminiviral nonanucleotide sequence. The virus isolate showed 97-99% sequence identities and close phylogenetic relationships with various isolates of Ageratum enation virus (AgEV); therefore, the isolate under study was identified as AgEV. The beta- and alphasatellite molecules were also identified to be associated with the disease based on their high sequence identities and close phylogenetic relationships with the respective molecules reported worldwide. Co-infiltration of agro-infectious clones of AgEV DNA-A and its betasatellite DNA induced leaf curl and enation symptoms after 25-35 days on A. cruentus, Nicotiana benthamiana, and N. glutinosa plants. We report the association of AgEV, betasatellite and alphasatellite components with yellow vein disease of A. cruentus from India.

  5. Repellent activity of plant-derived compounds against Amblyomma cajennense (Acari: Ixodidae) nymphs.

    PubMed

    Soares, Sara Fernandes; Borges, Lígia Miranda Ferreira; de Sousa Braga, Raquel; Ferreira, Lorena Lopes; Louly, Carla Cristina Braz; Tresvenzol, Leonice Manrique Faustino; de Paula, José Realino; Ferri, Pedro Henrique

    2010-01-20

    Repellence responses of Amblyomma cajennense nymphs to callicarpenal, intermedeol, Hyptis suaveolens essential oil, extract of Melia azedarach, Cymbopogon nardus, Spiranthera odoratissima, Chenopodium ambrosioides, Ageratum conyzoides, Mentha pulegium, Ruta graveolens, and Memora nodosa were studied. Among these the extract of C. nardus stood out because of the long-lasting repellence, maintaining, in the highest concentration, 35h of protection against 90% of the nymphs. The essential oil of H. suaveolens and the extracts of C. ambrosioides and A. conyzoides showed good repellence index (66%) when applied in high concentrations. However, greater protection could be obtained at higher concentrations but with a shorter repellence time. Callicarpenal, intermedeol, extract of M. Pulegium, and M. nodosa leaves showed moderate repellence in high concentrations. Extracts from M. azedarach, R. graveolens, S. odoratissima, and M. nodosa roots showed little or no repellent effect. These results show that some plant extracts may represent a promising alternative in the control of infestations by A. cajennense.

  6. Association of an Alphasatellite with Tomato Yellow Leaf Curl Virus and Ageratum Yellow Vein Virus in Japan is Suggestive of a Recent Introduction

    PubMed Central

    Shahid, Muhammad Shafiq; Ikegami, Masato; Waheed, Abdul; Briddon, Rob W.; Natsuaki, Keiko T.

    2014-01-01

    Samples were collected in 2011 from tomato plants exhibiting typical tomato leaf curl disease symptoms in the vicinity of Komae, Japan. PCR mediated amplification, cloning and sequencing of all begomovirus components from two plants from different fields showed the plants to be infected by Tomato yellow leaf curl virus (TYLCV) and Ageratum yellow vein virus (AYVV). Both viruses have previously been shown to be present in Japan, although this is the first identification of AYVV on mainland Japan; the virus previously having been shown to be present on the Okinawa Islands. The plant harboring AYVV was also shown to contain the betasatellite Tomato leaf curl Java betasatellite (ToLCJaB), a satellite not previously shown to be present in Japan. No betasatellite was associated with the TYLCV infected tomato plants analyzed here, consistent with earlier findings for this virus in Japan. Surprisingly both plants were also found to harbor an alphasatellite; no alphasatellites having previously been reported from Japan. The alphasatellite associated with both viruses was shown to be Sida yellow vein China alphasatellite which has previously only been identified in the Yunnan Province of China and Nepal. The results suggest that further begomoviruses, and their associated satellites, are being introduced to Japan. The significance of these findings is discussed. PMID:24424499

  7. Association of an alphasatellite with tomato yellow leaf curl virus and ageratum yellow vein virus in Japan is suggestive of a recent introduction.

    PubMed

    Shahid, Muhammad Shafiq; Ikegami, Masato; Waheed, Abdul; Briddon, Rob W; Natsuaki, Keiko T

    2014-01-14

    Samples were collected in 2011 from tomato plants exhibiting typical tomato leaf curl disease symptoms in the vicinity of Komae, Japan. PCR mediated amplification, cloning and sequencing of all begomovirus components from two plants from different fields showed the plants to be infected by Tomato yellow leaf curl virus (TYLCV) and Ageratum yellow vein virus (AYVV). Both viruses have previously been shown to be present in Japan, although this is the first identification of AYVV on mainland Japan; the virus previously having been shown to be present on the Okinawa Islands. The plant harboring AYVV was also shown to contain the betasatellite Tomato leaf curl Java betasatellite (ToLCJaB), a satellite not previously shown to be present in Japan. No betasatellite was associated with the TYLCV infected tomato plants analyzed here, consistent with earlier findings for this virus in Japan. Surprisingly both plants were also found to harbor an alphasatellite; no alphasatellites having previously been reported from Japan. The alphasatellite associated with both viruses was shown to be Sida yellow vein China alphasatellite which has previously only been identified in the Yunnan Province of China and Nepal. The results suggest that further begomoviruses, and their associated satellites, are being introduced to Japan. The significance of these findings is discussed.

  8. Leaving liza.

    PubMed

    Futcher, Jane

    2004-01-01

    Abstract This is Chapter Thirteen of Leaving Liza, a novel about life, death, love, friendship, jealousy and lesbian ex-lovers. In the novel, six women are spending the weekend at a beach house in Long Island's Hamptons, where they have gathered to be with their friend Liza, who is battling terminal ovarian cancer. Liza's lover, Jill, has agreed to the house party and helped plan the guest list. But, as she smolders with resentment at the attention Liza is getting and the depth of the women's friendships, she begins to come unraveled. After a severe asthma attack that requires an emergency room visit the day before, Jill conducts a seance, purporting to have contacted another of Liza's ex-lovers, who died a few months earlier. Now, on this last night of the house party, she lets Liza and her friends know what she's really feeling. The editors have asked me to add some "commentary" on the questions this story raises about the roles of ex-lovers. I would hope the scene reflects some of the tensions that can occur when ex-lovers choose to remain friends, particularly when those bonds provoke profound jealousy in both current and ex-lovers. For many of us, the job of assuaging and reassuring the current lover while maintaining intimate friendships with an ex-lover is simply too exhausting and prickly to endure. For others, it is worth the struggle. Liza and her friends clearly think it is. But at what point, they all wonder at this house party, does their hunger for honesty and their anger at being insulted and manipulated become more important than keeping the peace, and possibly their friendship with Liza? Perhaps only Liza's death will free them from this compromising coexistence.

  9. 5 CFR 630.503 - Leave from former leave systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Leave from former leave systems. 630.503... AND LEAVE Recredit of Leave § 630.503 Leave from former leave systems. An employee who earned leave under the leave acts of 1936 or any other leave system merged under subchapter I of chapter 63 of...

  10. Chemical Composition, Antioxidant, Anti-Inflammatory and Anti-Proliferative Activities of Essential Oils of Plants from Burkina Faso

    PubMed Central

    Bayala, Bagora; Bassole, Imaël Henri Nestor; Gnoula, Charlemagne; Nebie, Roger; Yonli, Albert; Morel, Laurent; Figueredo, Gilles; Nikiema, Jean-Baptiste; Lobaccaro, Jean-Marc A.; Simpore, Jacques

    2014-01-01

    This research highlights the chemical composition, antioxidant, anti-inflammatory and anti-proliferative activities of essential oils from leaves of Ocimum basilicum, Ocimum americanum, Hyptis spicigera, Lippia multiflora, Ageratum conyzoides, Eucalyptus camaldulensis and Zingiber officinale. Essential oils were analyzed by gas chromatography–mass spectrometry and gas chromatography–flame ionization detector. Major constituents were α-terpineol (59.78%) and β-caryophyllene (10.54%) for Ocimum basilicum; 1, 8-cineol (31.22%), camphor (12.730%), α-pinene (6.87%) and trans α-bergamotene (5.32%) for Ocimum americanum; β-caryophyllene (21%), α-pinene (20.11%), sabinene (10.26%), β-pinene (9.22%) and α-phellandrene (7.03%) for Hyptis spicigera; p-cymene (25.27%), β-caryophyllene (12.70%), thymol (11.88), γ-terpinene (9.17%) and thymyle acetate (7.64%) for Lippia multiflora; precocene (82.10%)for Ageratum conyzoides; eucalyptol (59.55%), α-pinene (9.17%) and limonene (8.76%) for Eucalyptus camaldulensis; arcurcumene (16.67%), camphene (12.70%), zingiberene (8.40%), β-bisabolene (7.83%) and β-sesquiphellandrène (5.34%) for Zingiber officinale. Antioxidant activities were examined using 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) methods. O. basilicum and L. multiflora exhibited the highest antioxidant activity in DPPH and ABTS tests, respectively. Anti-inflammatory properties were evaluated by measuring the inhibition of lipoxygenase activity and essential oil of Z. officinale was the most active. Anti-proliferative effect was assayed by the measurement of MTT on LNCaP and PC-3 prostate cancer cell lines, and SF-763 and SF-767 glioblastoma cell lines. Essential oils from A. conyzoides and L. multiflora were the most active on LNCaP and PC-3 cell lines, respectively. The SF-767 glioblastoma cell line was the most sensitive to O. basilicum and L. multiflora EOs while essential oil of A. conyzoides

  11. Problematising Early School Leaving

    ERIC Educational Resources Information Center

    Ross, Alistair; Leathwood, Carole

    2013-01-01

    Early school leaving has been identified as a key policy priority across Europe. In this article, we critically discuss the underpinning assumptions and rationale for this policy focus, challenging the association that is made between early school leaving, economic growth and employment. We suggest that ESL is important, not because it is…

  12. Falling for Clay Leaves.

    ERIC Educational Resources Information Center

    Kernan, Christine

    2002-01-01

    Describes an art project that integrated science and art education. Explains that students create ceramic bowls by using real leaves. Discusses the process of creating the ceramic bowls, including how to glaze the bowls. Includes a list of materials. (CMK)

  13. Icephobicity of Leaves

    NASA Astrophysics Data System (ADS)

    Kavehpour, H. Pirouz; Shirazi, Elika T.; Alizadeh-Birjandi, Elaheh

    2016-11-01

    Ice adhesion and excessive accumulation on exposed structures and equipment are well known to cause serious problems in cold-climate regions; therefore, the development of coatings that can resist icing can solve many challenges in various areas of industry. This work was inspired by nature and ice-resistivity and superhydrophobicity of plants leaves. Kale is an example of a plant that can be harvested in winter. It shows superhydrophobic behavior, which is normally known as an advantage for cleaning the leaves, but we were able to show that its surface structure and high contact angle of water drops on kale leaves could delay the ice formation process making it a good candidate for an ice-repellent coating. We have performed in-depth experimental analyses on how different plants can prevent icing, and contact angle measurements and scanning electron microscopy (SEM) of the leaves were taken to further mimic their surface morphology.

  14. 75 FR 75363 - Absence and Leave; Sick Leave

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-03

    ...The U.S. Office of Personnel Management is issuing final regulations on the use of sick leave and advanced sick leave for serious communicable diseases, including pandemic influenza when appropriate. We are also permitting employees to substitute up to 26 weeks of accrued or accumulated sick leave for unpaid Family and Medical Leave Act (FMLA) leave to care for a seriously injured or ill......

  15. Leaves: Nature's Solar Collectors

    ERIC Educational Resources Information Center

    Isabelle, Aaron D.; de Groot, Cornelis

    2009-01-01

    One of the most captivating things about plants is the way they capture the Sun's energy, but this can be a difficult topic to cover with elementary students. Therefore, to help students to make a concrete connection to this abstract concept, this series of solar-energy lessons focuses on leaves and how they act as "solar collectors." As students…

  16. Identifying Early School Leaving

    ERIC Educational Resources Information Center

    Poole, Millicent E.

    1978-01-01

    Using a matched sample of students who stay in school and those who drop out, or leave early, an attempt was made, via multiple discriminant analysis, to identify the significant characteristics which distinguish "drop outs" from their peers who remain at school. Results indicated that both types of students have similar value orientations and…

  17. Maternity Leave in Taiwan

    ERIC Educational Resources Information Center

    Feng, Joyce Yen; Han, Wen-Jui

    2010-01-01

    Using the first nationally representative birth cohort study in Taiwan, this paper examines the role that maternity leave policy in Taiwan plays in the timing of mothers returning to work after giving birth, as well as the extent to which this timing is linked to the amount of time mothers spend with their children and their use of breast milk…

  18. Maternity Leave in Taiwan

    PubMed Central

    Feng, Joyce Yen; Han, Wen-Jui

    2011-01-01

    Using the first nationally representative birth cohort study in Taiwan, this paper examines the role that maternity leave policy in Taiwan plays in the timing of mothers returning to work after giving birth, as well as the extent to which this timing is linked to the amount of time mothers spend with their children and their use of breast milk versus formula. We found that the time when mothers returned to work coincided with the duration of guaranteed leave. In particular, mothers with a labor pension plan resumed work significantly earlier than mothers with no pension plan, and mothers with no pension plan returned to work significantly later than those with pension plans. The short leave of absence guaranteed under existing policies translated into mothers spending less time with their children and being more likely to exclusively use formula by 6 months after birth. In contrast, mothers who resumed work later than 6 months after birth were more likely to have not worked before birth or to have quit their jobs during pregnancy. Implications and recommendations for parental leave policy in Taiwan are discussed. PMID:21603074

  19. Water isotopologues in leaves

    NASA Astrophysics Data System (ADS)

    Cuntz, M.; Ogée, J.; Farquhar, G. D.; Cernusak, L. A.; Peylin, P.; Bariac, T.

    2007-12-01

    Leaf water isotope enrichment is a cornerstone of a variety of isotopic applications. It imprints on different substances such as atmospheric CO2, O2, and plant organic matter. But different applications use enrichment in different parts of the leaf and weighted by different fluxes. For example, leaf organic matter is determined by the assimilation-weighted average bulk water enrichment. Atmospheric CO2 and O2 are determined by the enrichment near the evaporating sites, either weighted by the one-way CO2 flux from the stomata to the atmosphere or by electron transport, resp. These applications of leaf water enrichment are used from the leaf level up to global scales. It is therefore essential to understand the time course of leaf water enrichment at both the evaporating sites and in the mesophyll but also to asses the suitability of simple models such as the Craig & Gordon (1965) steady-state prediction or the Dongmann et al. (1974) non-steady-state model. We describe here advection and diffusion of water isotopologues in leaves in the non-steady state. We first show how this relates to earlier non-steady state bulk leaf water enrichment models. The adv.-diff. model compares very well with observations of bulk mesophyll water during the whole diel cycle. It compares well with the enrichment at the evaporative sites during the day but shows some deviations at night. It is clear that night-time stomatal conductance should be measured in the future. However, varying mesophyll water volume did not seem critical for a good prediction. In addition, observations of single diurnal cycles do not constrain the effective length in the mesophyll. Finally, we show when simpler models of leaf water enrichment are suitable for applications of leaf water isotopes once weighted with the appropriate gas exchange flux. We then present a two-dimensional adv.-diff. description of leaf water enrichment along monocot leaves. The model reproduces well all published measurements along

  20. [Precautionary maternity leave in Tirol].

    PubMed

    Ludescher, K; Baumgartner, E; Roner, A; Brezinka, C

    1998-01-01

    Under Austrian law, precautionary maternity leave is a decree issued by the district public health physician. It forbids a pregnant woman to work and mandates immediate maternity leave. Regular maternity leave for all women employed in all jobs begins at 32 weeks of gestation. Women who work in workplaces deemed dangerous and women with a history of obstetric problems such as premature or growth-retarded babies from previous pregnancies are regularly 'sent' into precautionary maternity leave. The public health physicians of Tirol's nine administrative districts were interviewed and supplied data on precautionary maternity leave from their districts. In 100 women who attended the clinic for pregnancies at risk of the Obstetrics/Gynecology Department of Innsbruck University Hospital and who had already obtained precautionary maternity leave, the medical/administrative procedure was studied in each case and correlated with pregnancy outcome. The town district of Innsbruck and the district that comprises the suburbs of the provincial capital had the highest rates of precautionary maternity leave. The town district of Innsbruck had a rate of 24.3% of all pregnant women (employed and not employed) in precautionary maternity leave in 1997, whereas the whole province of Tirol had 13.4%. More than 80% of decrees for precautionary maternity leave are issued by district public health physicians on the basis of written recommendations from gynecologists. One third of women who are sent into precautionary maternity leave are issued the decree prior to 12 weeks of gestation - mostly cases of multiple pregnancies and women with previous miscarriages. The present system of precautionary maternity leave appears to work in the sense that most working pregnant women with risk factors are correctly identified - with most errors on the side of caution. As the system also helps employers - the employee's pay is paid from the federal family support fund and state insurance once she is in

  1. Starch metabolism in leaves.

    PubMed

    Orzechowski, Sławomir

    2008-01-01

    Starch is the most abundant storage carbohydrate produced in plants. The initiation of transitory starch synthesis and degradation in plastids depends mainly on diurnal cycle, post-translational regulation of enzyme activity and starch phosphorylation. For the proper structure of starch granule the activities of all starch synthase isoenzymes, branching enzymes and debranching enzymes are needed. The intensity of starch biosynthesis depends mainly on the activity of AGPase (adenosine 5'-diphosphate glucose pyrophosphorylase). The key enzymes in starch degradation are beta-amylase, isoamylase 3 and disproportionating enzyme. However, it should be underlined that there are some crucial differences in starch metabolism between heterotrophic and autotrophic tissues, e.g. is the ability to build multiprotein complexes responsible for biosynthesis and degradation of starch granules in chloroplasts. The observed huge progress in understanding of starch metabolism was possible mainly due to analyses of the complete Arabidopsis and rice genomes and of numerous mutants with altered starch metabolism in leaves. The aim of this paper is to review current knowledge on transient starch metabolism in higher plants.

  2. Key Obama officials leave administration

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2013-01-01

    Secretary of the Interior Ken Salazar is one of the latest members of the Obama administration to announce that he is leaving his position near the start of President Obama's second term in office. Salazar, who has served as interior secretary since January 2009, intends to leave the department by the end of March, the department noted on 16 January. Salazar joins a number of other key officials who are planning to leave the administration. They include Environmental Protection Agency administrator Lisa Jackson, National Oceanic and Atmospheric Administration administrator Jane Lubchenco, and U.S. Geological Survey director Marcia McNutt.

  3. Professional Development Leave: The Florida Model.

    ERIC Educational Resources Information Center

    Perdue, Robert W.

    The history of professional development leave for librarians in the Florida State University System was examined, and an inventory was made of all leaves taken in the state's nine universities. The state's leave policy was judged to be generous when compared to the policies of other libraries in the nation. The leaves were examined for their…

  4. Leaves: Elevated CO2 levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Burning fossil fuels and land use changes such as deforestation and urbanization have led to a dramatic rise in the concentration of carbon dioxide (CO2) in the atmosphere since the onset of the Industrial Revolution. The highly dilute CO2 from the atmosphere enters plant leaves where it is concentr...

  5. The thermal conductivity of leaves.

    PubMed

    Hays, R L

    1975-01-01

    Thermal conductivities of fresh leaves, both unmodified and infiltrated with water, were measured. Samples were placed between silver plates of known and differing temperatures, and the time required to boil off a constant volume of liquid was measured. The species used are evergreens: Eucalyptus globulus Labill. (sclerophyllous) with isolateral leaf symmetry; and Peperomia obtusifolia A. Dietr. (succulent), Citrus limon Burm. f. (mesophyllous), Arbutus menziessii Pursh. (sclerophyllous), and Heteromeles arbutifolia M. Roem. (sclerophyllous), all with bilateral leaf symmetry. Mean values found were in the range of 0.268 to 0.573 W/m · °C for fresh leaves, and 0.540 to 0.548 W/m · °C for leaves infiltrated with water. An analysis of errors in the technique indicated that these values may be somewhat low. These results are several times higher than previously reported values. It is concluded that ordinary mesophytic and xerophytic leaves will not develop large gradients in temperature between the surfaces.

  6. 5 CFR 630.1015 - Movement between voluntary leave bank and leave transfer programs.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1015 Movement... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Movement between voluntary leave bank and... with the employee's right to submit an application to become a leave donor (or leave contributor,...

  7. 5 CFR 630.1015 - Movement between voluntary leave bank and leave transfer programs.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1015 Movement... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Movement between voluntary leave bank and... with the employee's right to submit an application to become a leave donor (or leave contributor,...

  8. 5 CFR 630.1015 - Movement between voluntary leave bank and leave transfer programs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1015 Movement... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Movement between voluntary leave bank and... with the employee's right to submit an application to become a leave donor (or leave contributor,...

  9. 5 CFR 630.1015 - Movement between voluntary leave bank and leave transfer programs.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1015 Movement... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Movement between voluntary leave bank and... with the employee's right to submit an application to become a leave donor (or leave contributor,...

  10. 5 CFR 630.1015 - Movement between voluntary leave bank and leave transfer programs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1015 Movement... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Movement between voluntary leave bank and... with the employee's right to submit an application to become a leave donor (or leave contributor,...

  11. Carnivorous leaves from Baltic amber.

    PubMed

    Sadowski, Eva-Maria; Seyfullah, Leyla J; Sadowski, Friederike; Fleischmann, Andreas; Behling, Hermann; Schmidt, Alexander R

    2015-01-06

    The fossil record of carnivorous plants is very scarce and macrofossil evidence has been restricted to seeds of the extant aquatic genus Aldrovanda of the Droseraceae family. No case of carnivorous plant traps has so far been reported from the fossil record. Here, we present two angiosperm leaves enclosed in a piece of Eocene Baltic amber that share relevant morphological features with extant Roridulaceae, a carnivorous plant family that is today endemic to the Cape flora of South Africa. Modern Roridula species are unique among carnivorous plants as they digest prey in a complex mutualistic association in which the prey-derived nutrient uptake depends on heteropteran insects. As in extant Roridula, the fossil leaves possess two types of plant trichomes, including unicellular hairs and five size classes of multicellular stalked glands (or tentacles) with an apical pore. The apices of the narrow and perfectly tapered fossil leaves end in a single tentacle, as in both modern Roridula species. The glandular hairs of the fossils are restricted to the leaf margins and to the abaxial lamina, as in extant Roridula gorgonias. Our discovery supports current molecular age estimates for Roridulaceae and suggests a wide Eocene distribution of roridulid plants.

  12. Carnivorous leaves from Baltic amber

    PubMed Central

    Sadowski, Eva-Maria; Seyfullah, Leyla J.; Sadowski, Friederike; Fleischmann, Andreas; Behling, Hermann; Schmidt, Alexander R.

    2015-01-01

    The fossil record of carnivorous plants is very scarce and macrofossil evidence has been restricted to seeds of the extant aquatic genus Aldrovanda of the Droseraceae family. No case of carnivorous plant traps has so far been reported from the fossil record. Here, we present two angiosperm leaves enclosed in a piece of Eocene Baltic amber that share relevant morphological features with extant Roridulaceae, a carnivorous plant family that is today endemic to the Cape flora of South Africa. Modern Roridula species are unique among carnivorous plants as they digest prey in a complex mutualistic association in which the prey-derived nutrient uptake depends on heteropteran insects. As in extant Roridula, the fossil leaves possess two types of plant trichomes, including unicellular hairs and five size classes of multicellular stalked glands (or tentacles) with an apical pore. The apices of the narrow and perfectly tapered fossil leaves end in a single tentacle, as in both modern Roridula species. The glandular hairs of the fossils are restricted to the leaf margins and to the abaxial lamina, as in extant Roridula gorgonias. Our discovery supports current molecular age estimates for Roridulaceae and suggests a wide Eocene distribution of roridulid plants. PMID:25453067

  13. 46 CFR 310.8 - Leave.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... hospitalized, sick at home, or confined in the sick bay, leave shall not exceed four (4) months. (2) For an... may be granted leaves of absence without pay, as approved by the Superintendent, for periods not...

  14. 46 CFR 310.8 - Leave.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... hospitalized, sick at home, or confined in the sick bay, leave shall not exceed four (4) months. (2) For an... may be granted leaves of absence without pay, as approved by the Superintendent, for periods not...

  15. 46 CFR 310.8 - Leave.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... hospitalized, sick at home, or confined in the sick bay, leave shall not exceed four (4) months. (2) For an... may be granted leaves of absence without pay, as approved by the Superintendent, for periods not...

  16. 46 CFR 310.8 - Leave.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... hospitalized, sick at home, or confined in the sick bay, leave shall not exceed four (4) months. (2) For an... may be granted leaves of absence without pay, as approved by the Superintendent, for periods not...

  17. Pregnancy, Teaching, and Leaving before Year's End.

    ERIC Educational Resources Information Center

    Abdulrashid, Jamila

    This essay highlights one pregnant middle school teacher's experiences with taking a mid-year leave. She used entries from her personal diary to reflect on how she felt about her leave, while her students wrote letters and notes expressing their anxieties about her leaving. The discussion of planning a pregnancy and the stages of pregnancy, along…

  18. Parental Leave and Productivity. Current Research.

    ERIC Educational Resources Information Center

    Friedman, Dana E., Ed.; And Others

    This report consists of papers, commissioned by the Family Work Institute, by expert policy makers in the area of parental leave. The report consists of eight papers: (1) "The Impact of Childbearing on Employment" (James T. Bond); (2) "Fathers and Parental Leave: A Perspective" (Joseph H. Pleck); (3) Parental Leave and…

  19. Compassionate Care Leave & Benefits. CAUT Briefing Note

    ERIC Educational Resources Information Center

    Canadian Association of University Teachers, 2016

    2016-01-01

    Compassionate care leave and benefits were introduced in 2003/04 to help employees cope with this difficult work-life balance challenge. Employment Standards legislation and the Employment Insurance program (EI) were amended to provide leave without pay, with payment of EI benefits for compassionate care leave. Collective agreements have been…

  20. Exploring Why Career Changers Leave Teaching

    ERIC Educational Resources Information Center

    Cuddapah, Jennifer L.; Beaty-O'Ferrall, Mary Ellen; Masci, Frank J.; Hetrick, Monica

    2011-01-01

    Survey data were used to explore the current teaching status and reasons for leaving or considering leaving teaching for 154 career changers who all graduated from a Master of Arts in Teaching (MAT) program over a 9-year time period. Respondents provided information about reasons for leaving teaching, indicating personal/family, career, and school…

  1. 5 CFR 630.1104 - Donations from a leave bank to an emergency leave transfer program.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Donations from a leave bank to an emergency leave transfer program. 630.1104 Section 630.1104 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Emergency Leave Transfer Program § 630.1104...

  2. Resource capture by single leaves

    SciTech Connect

    Long, S.P.

    1992-05-01

    Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfully considered without simultaneous understanding of implications at the canopy level. 36 refs., 5 figs., 1 tab.

  3. Mercury uptake into poplar leaves.

    PubMed

    Assad, Mohamad; Parelle, Julien; Cazaux, David; Gimbert, Frédéric; Chalot, Michel; Tatin-Froux, Fabienne

    2016-03-01

    Tailings dumps require mercury stabilization to prevent air pollution by evaporated mercury, which can be achieved through plant covers. Plants are considered a net sink for atmospheric Hg via incorporation into leaf tissues. However, most studies related to Hg uptake by plants have considered plants exposed to only atmospheric Hg, whereas in the case of tailings dumps, plants are potentially exposed to both soil and atmospheric Hg. The goal of this work is to evaluate the relative contributions of root and atmospheric pathways by growing poplar (Populus trichocarpa X Populus maximowiczii/var Skado) cuttings on either control or polluted substrates and under either natural or controlled exposure conditions. We showed that foliar Hg concentrations significantly increased with age, reaching 120 ng g(-1) dry mass when poplars were exposed to Hg-contaminated substrate under natural exposure. Remarkably, we did not observe significantly different Hg concentrations in poplar leaves grown on either the control or polluted substrates when cultivated together in growth chambers. Our set of data prompted us to conclude that Hg entry into poplar leaves is exclusively through an atmospheric pathway. Our results are discussed in line with existing literature.

  4. Phytic acid in green leaves.

    PubMed

    Hadi Alkarawi, H; Zotz, G

    2014-07-01

    Phytic acid or phytate, the free-acid form of myo-inositolhexakiphosphate, is abundant in many seeds and fruits, where it represents the major storage form of phosphorus. Although also known from other plant tissues, available reports on the occurrence of phytic acid, e.g. in leaves, have never been compiled, nor have they been critically reviewed. We found 45 published studies with information on phytic acid content in leaves. Phytic acid was almost always detected when studies specifically tried to detect it, and accounted for up to 98% of total P. However, we argue that such extreme values, which rival findings from storage organs, are dubious and probably result from measurement errors. Excluding these high values from further quantitative analysis, foliar phytic acid-P averaged 2.3 mg·g(-1) , and represented, on average, 7.6% of total P. Remarkably, the ratio of phytic acid-P to total P did not increase with total P, we even detected a negative correlation of the two variables within one species, Manihot esculenta. This enigmatic finding warrants further attention.

  5. The cardioprotective power of leaves

    PubMed Central

    Boncler, Magdalena; Watala, Cezary

    2015-01-01

    Lack of physical activity, smoking and/or inappropriate diet can contribute to the increase of oxidative stress, in turn affecting the pathophysiology of cardiovascular diseases. Strong anti-oxidant properties of plant polyphenolic compounds might underlie their cardioprotective activity. This paper reviews recent findings on the anti-oxidant activity of plant leaf extracts and emphasizes their effects on blood platelets, leukocytes and endothelial cells – the targets orchestrating the development and progression of cardiovascular diseases. We also review the evidence linking supplementation with plant leaf extracts and the risk factors defining the metabolic syndrome. The data point to the importance of leaves as an alternative source of polyphenolic compounds in the human diet and their role in the prevention of cardiovascular diseases. PMID:26322095

  6. Adolescent mothers leaving multigenerational households.

    PubMed

    Oberlander, Sarah E; Shebl, Fatma M; Magder, Laurence S; Black, Maureen M

    2009-01-01

    This study examined how the developmental processes of autonomy and relatedness are related to changes in the residential status of 181 first-time, adolescent, urban, low-income, African American mothers over the first 24 months postpartum. Although adolescent mothers were eager to live independently, few made a clear transition out of the multigenerational household; 56% lived in the household of origin continuously (IN), 21% left and never returned (OUT), and 23% had multiple moves in and out of the household (IN/OUT). Older adolescent maternal age, less supportive adolescent mother-grandmother relations, and high household density were associated with leaving the household of origin. The IN/OUT group had difficulty adopting the roles of adult and parent. Helping adolescent mothers and grandmothers negotiate roles to reduce conflict may promote autonomy and relatedness, allowing mothers to learn parenting skills, qualify for public assistance, and continue their education.

  7. Cooling experiments using dummies covered by leaves.

    PubMed

    Althaus, L; Stückradt, S; Henssge, C; Bajanowski, T

    2007-03-01

    One main method to estimate the time of death is the measurement of the body temperature. The cooling of a corpse depends on a number of conditions including the surroundings. In cases where the cooling conditions differ from the defined standard, a corrective factor is used to characterise the influence of clothing, air movement, the properties of the supporting base and the humidity. Nothing is known about the significance of other circumstances, for example of a tegument by leaves or wet leaves. Therefore, the cooling of dummies which were placed on a 2-cm-thick layer of wet/dry leaves and covered by a 10-cm-thick layer of leaves was investigated. Corrective factors of 1.0 for wet leaves on the ground and of 1.3 and 1.5 for drier leaves were found. If the dummies were additionally covered, corrective factors ranged between 1.8 and 2.7.

  8. Paid Sick Leave and Job Stability.

    PubMed

    Hill, Heather D

    2013-05-01

    A compelling, but unsubstantiated, argument for paid sick leave legislation is that workers with leave are better able to address own and family member health needs without risking a voluntary or involuntary job separation. This study tests that claim using the Medical Expenditure Panel Survey and regression models controlling for a large set of worker and job characteristics, as well as with propensity score techniques. Results suggest that paid sick leave decreases the probability of job separation by at least 2.5 percentage points, or 25%. The association is strongest for workers without paid vacation leave and for mothers.

  9. Paid Sick Leave and Job Stability

    PubMed Central

    Hill, Heather D.

    2013-01-01

    A compelling, but unsubstantiated, argument for paid sick leave legislation is that workers with leave are better able to address own and family member health needs without risking a voluntary or involuntary job separation. This study tests that claim using the Medical Expenditure Panel Survey and regression models controlling for a large set of worker and job characteristics, as well as with propensity score techniques. Results suggest that paid sick leave decreases the probability of job separation by at least 2.5 percentage points, or 25%. The association is strongest for workers without paid vacation leave and for mothers. PMID:24235780

  10. Leaving home in Spain: a regional analysis.

    PubMed

    Holdsworth, C

    1998-12-01

    "This paper compares regional patterns of leaving home in Spain during the 1970s and 1980s based on analysis of the 1991 Spanish Sociodemographic Survey. The purpose of this analysis is to demonstrate that while nationally Spain is representative of a southern European pattern of leaving home, (i.e. relatively late and closely associated with partnership formation), there is considerable regional variation in timing, incidence and initial destinations on leaving home. These differences are explored using hazard rates of leaving home by destination and birth cohort for 11 Spanish regions."

  11. Ensiling Characteristics of Alfalfa Leaves and Stems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The separate harvesting of alfalfa leaves and stems would provide farmers more flexibility in the harvesting and utilization of alfalfa, but a key issue is storage. In three trials, unwilted alfalfa leaves were ensiled alone or with cell wall degrading enzymes, formic acid or lactic acid bacterial i...

  12. A Feminist Perspective on Parental Leave Policies

    ERIC Educational Resources Information Center

    Sallee, Margaret W.

    2008-01-01

    This article focuses on the ways that three feminist theories--liberal feminism, cultural feminism, and feminist poststructuralism--might be used to craft parental leave policies. After examining each theory in detail, the article concludes by offering one example of an ideal parental leave policy that combines the best features of each theory to…

  13. When and Why Dropouts Leave High School

    ERIC Educational Resources Information Center

    Stearns, Elizabeth; Glennie, Elizabeth J.

    2006-01-01

    Teens may leave school because of academic failure, disciplinary problems, or employment opportunities. In this article, the authors test whether the reasons dropouts leave school differ by grade level and age. We compare dropout rates and reasons across grade levels and ages for all high school students, ethnic groups, and gender groups. Across…

  14. Developments in Educational Leave of Absence.

    ERIC Educational Resources Information Center

    Organisation for Economic Cooperation and Development, Paris (France). Centre for Educational Research and Innovation.

    The document evaluates present international developments in the area of leave of absence during working hours for educational purposes. Part 1, Educational Leave of Absence: A Comparative Analysis, contains five chapters: (1) Towards a New Right to Education, discussing recurrent education, the world of work, the International Labor Organization,…

  15. Late Adolescents' Conceptualizations of Home-Leaving.

    ERIC Educational Resources Information Center

    Moore, DeWayne; Hotch, Deborah F.

    1981-01-01

    An initial attempt to obtain normative data on adolescent home-leaving is represented. Young adults defined home-leaving as personal control, economic independence, residence, physical separation, school affiliation, dissociation, emotional separation, or graduation. The subjective meaning of these definitions is discussed. (Author/GK)

  16. Changes in spectral properties of detached leaves

    NASA Technical Reports Server (NTRS)

    Daughtry, C. S. T.; Biehl, L. L.

    1984-01-01

    If leaf senescence can be delayed for several days without significant changes in spectral properties, then samples of leaves at remote test sites could be prepared and shipped to laboratories to measure spectral properties. The changes in spectral properties of detached leaves were determined. Leaves from red birch and red pine were immersed in water or 0.001 M benzylaminopurine (BAP) and stored in plastic bags in the dark at either 5 or 25 C. Total directional-hemispherical reflectance and transmittance of the adaxial surface of birch leaves were measured over the 400 to 1100 nm wavelength region with a spectroradiometer and integrating sphere. Pine needles were taped together and reflectance of the mat of needles was measured. Spectral properties changed less than 5% of initial values during the first week when leaves were stored at 5 C. Storage at 25 C promoted rapid senescence and large changes in spectral properties. BAP delayed, but did not stop, senescence at 25 C.

  17. Influence of pesticides on yeasts colonizing leaves.

    PubMed

    Vadkertiová, Renata; Sláviková, Elena

    2011-01-01

    The effect of nine different pesticides on the growth of yeasts isolated from the leaves of fruit and forest trees was investigated. Four insecticides (with the active ingredients: thiacloprid, deltamethrin, lambdacyhalothrin, and thiamethoxam) and five fungicides (with the effective substances: bitertanol, kresoxim-methyl, mancozeb, trifloxystrobin, and cupric oxychloride) were tested. The concentrations of chemicals were those recommended by the manufacturers for the spraying of trees. The yeast strains isolated from the leaves of fruit trees were not sensitive to any of the insecticides. The majority of yeast strains isolated from the leaves of forest trees were either not sensitive or only to a small extent. While Rhodotorula mucilaginosa and Pichia anomala were not affected by any insecticide, the strains of Cryptococcus laurentii and Rhodotorula glutinis showed the highest sensitivity. The effects of fungicides on the growth of isolated yeasts were more substantial. The fungicide Dithane DG (mancozeb) completely inhibited the growth of all yeasts. All strains isolated from fruit tree leaves were more resistant to the tested fungicides than those isolated from the leaves of forest trees. The most resistant strains from the leaves of fruit trees belonged to the species Metschnikowia pulcherrima, Pichia anomala, and Saccharomyces cerevisiae, whereas Cryptococcus albidus and C. laurentii, originating from the leaves of forest trees, showed the highest sensitivity to fungicides.

  18. 5 CFR 550.1207 - Recrediting annual leave.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... of title 5, United States Code, but is covered by a different leave system, the employing agency must... leave than can be recredited under the different leave system, the employee must refund only the amount... formal leave system to which his or her annual leave can be recredited, the employing agency...

  19. 5 CFR 630.502 - Sick leave recredit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... different leave systems under section 6308 of title 5, United States Code, 7 calendar days of sick leave are... leave system to which he or she can transfer only a part of his or her sick leave is entitled to a... employee returns to the leave system under which it was earned on or after December 2, 1994. (f)...

  20. Phytochemical and antifungal activities of Uvaria. chamae leaves and roots, Spondias mombin leaves and bark and Combretum racemosum leaves.

    PubMed

    Okwuosa, O M T B; Chukwura, E I; Chukwuma, G O; Okwuosa, C N; Enweani, I B; Agbakoba, N R; Chukwuma, C M; Manafa, P O; Umedum, C U

    2012-12-01

    The effects of crude and dilutions of aqueous, methanolic and n-hexane extracts of Uvaria chamae (roots and leaves), Spondias mombin (leaves and bark) and Combretum racemosum (Leaves), on pathogenic candida albicans and aspergillus niger was studied. The aim was to contribute to the search for a cheaper, conventional cure for both fungi. Phytochemical analysis revealed varying degrees of alkaloids, glycosides, saponin, lipid and oil, tannins, flavonoids, terpenoids and acids. Agar diffusion method was used for anti fungal assay. Minimum inhibitory concentration (mic) used was 10 mg/ml of extract and dilutions of the non polar solvents of 10 (-1) and 10(-2) was used. Results showed that none of the plant parts was active against aspergillus niger. Combretum racemosum had no antifungal effect on tested organisms as well as the different dilutions. However crude methanolic extract of uvaria (roots and leaves), spondias ( bark and leaves ), and n-hexane extracts of uvaria (leaves and roots), produced anti candidal effects with diameters in this order 14.67 +/- 0.72mm, 10.67 +/- 0.52 mm, 11.00 +/- 0.47 mm, 15.00 +/- 0.47 mm, and 14.67 +/- 0.72 mm respectively. Some of the plant parts especially uvaria had zones of inhibition at a confidence limit comparable with control drug which is ketoconazole and it had inhibitory effects at a diameter of 20.06 +/- 0.40 mm.

  1. Auxin level and regeneration of Begonia leaves.

    PubMed

    Heide, O M

    1968-06-01

    As previously found, both the level of ether-extractable auxin (presumably indole-3-acetic acid) and the root-forming ability of B.xcheimantha leaves are increased under long-day conditions by high temperature, whereas the capacity for adventitious bud formation is reduced. However, this relation is present under relatively high light intensity only. Under the low light intensities in late fall neither auxin level nor regeneration ability were significantly affected by temperature.Dark treatment of detached leaves for 2 to 16 days greatly counteracted the inhibitory effect of high temperature on bud formation and reduced both the auxin level and the root-forming ability of the leaves.The great seasonal changes in the regeneration ability of Begonia leaves seem to be the result of a complex interaction of temperature, day-length, and daily light energy on the level of endogenous auxin and other growth regulators.

  2. 46 CFR 310.8 - Leave.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... emergency due to the serious illness, injury or death of a very near relative, leave shall not exceed seven... absence if they continue to meet all requirements for graduation in this part, including age requirements....

  3. Anthelmintic activity of leaves of justicia beddomei.

    PubMed

    Srinivasa, U; Rao, J Venkateshwara; Krupanidhi, A M; Shanmukhappa, S

    2007-01-01

    Ethanolic and Chloroform extract of leaves of Justicia beddomei were evaluated separately for anthelmintic activity on adult Indian earthworms Pheretima posthuma, using Piperazine citrate as reference standard. The results indicated that ethanolic extract was more potent than the chloroform extract.

  4. The Chromatography of Leaves and Inks.

    ERIC Educational Resources Information Center

    Chemecology, 1997

    1997-01-01

    Describes the use of a simple process known as chromatography to separate and observe the color pigments in leaves, inks, and other materials. Provides some historical background and detailed procedures. (DDR)

  5. Pharmacognostical studies on Zanthoxylum armatum leaves

    PubMed Central

    Verma, Nitin; Khosa, R. L.

    2009-01-01

    The present study deals with the Pharmacognostical investigations on the leaves of Zanthoxylum armatum along with fluorescence characteristics ash and extractive values with an aim to identify and differentiate if from its possible adulterants and / or substitutes. PMID:22557335

  6. Potential therapeutic use of herbal extracts in trypanosomiasis.

    PubMed

    Teixeira, Thaise L; Teixeira, Samuel Cota; da Silva, Claudio Vieira; de Souza, Maria A

    2014-01-01

    The aim of the present study was to evaluate the effects of crude extracts from Handroanthus impetiginosa, Ageratum conyzoides, and Ruta graveolens on Leishmania amazonensis and Trypanosoma cruzi infection in vitro. The results showed that the extracts caused significant toxicity in promastigotes and trypomastigotes. A significant decrease in the rate of cell invasion by pretreated trypomastigotes and promastigotes was also observed. The extracts caused a significant reduction of the multiplication of intracellular amastigotes of both parasites. Therefore, these herbal extracts may be potential candidates for the development of drugs for the treatment of leishmaniasis and Chagas disease.

  7. Fossil pollen as a guide to conservation in the Galapagos.

    PubMed

    van Leeuwen, Jacqueline F N; Froyd, Cynthia A; van der Knaap, W O; Coffey, Emily E; Tye, Alan; Willis, Katherine J

    2008-11-21

    Paleoecological evidence from the past 8000 years in the Galápagos Islands shows that six presumed introduced or doubtfully native species (Ageratum conyzoides, Borreria laevis/Diodia radula-type, Brickellia diffusa, Cuphea carthagenensis, Hibiscus diversifolius, and Ranunculus flagelliformis) are in fact native to the archipelago. Fossil pollen and macrofossils from four sites in the highlands of Santa Cruz Island reveal that all were present thousands of years before the advent of human impact, refuting their classification as introduced species. These findings have substantial implications not only for conservation in Galápagos but for the management of introduced species and pantropical weeds in general.

  8. Potential therapeutic use of herbal extracts in trypanosomiasis

    PubMed Central

    Teixeira, Thaise L; Teixeira, Samuel Cota; da Silva, Claudio Vieira; de Souza, Maria A

    2014-01-01

    The aim of the present study was to evaluate the effects of crude extracts from Handroanthus impetiginosa, Ageratum conyzoides, and Ruta graveolens on Leishmania amazonensis and Trypanosoma cruzi infection in vitro. The results showed that the extracts caused significant toxicity in promastigotes and trypomastigotes. A significant decrease in the rate of cell invasion by pretreated trypomastigotes and promastigotes was also observed. The extracts caused a significant reduction of the multiplication of intracellular amastigotes of both parasites. Therefore, these herbal extracts may be potential candidates for the development of drugs for the treatment of leishmaniasis and Chagas disease. PMID:24548158

  9. Phytotoxicity of the volatile monoterpene citronellal against some weeds.

    PubMed

    Singh, Harminder Pal; Batish, Daizy R; Kaur, Shalinder; Kohli, Ravinder K; Arora, Komal

    2006-01-01

    A study was undertaken to assess the phytotoxicity of citronellal, an oxygenated monoterpenoid with an aldehyde group, towards some weedy species [Ageratum conyzoides L., Chenopodium album L., Parthenium hysterophorus L., Malvastrum coromandelianum (L.), Garcke, Cassia occidentalis L. and Phalaris minor Retz.]. A significant effect on weed emergence and early seedling growth was observed in a dose-response based laboratory bioassay in a sand culture. Emergence of all test weeds was completely inhibited at 100 micro/g sand content of citronellal. Seeds of A. conyzoides and P. hysterophorus failed to emerge even at 50 microg/g content. Root length was inhibited more compared to shoot length. The failure of root growth was attributed to the effect of citronellal on the mitotic activity of growing root tips cells as ascertained by the onion root tip bioassay. At 2.5 mM treatment of citronellal, mitosis was completely suppressed and at higher concentrations cells showed various degrees of distortion and were even enucleated. The post-emergent application of citronellal also caused visible injury in the form of chlorosis and necrosis, leading to wilting and even death of test weeds. Among the test weeds, the effect was severe on C. album and P. hysterophorus. There was loss of chlorophyll pigment and reduction in cellular respiration upon citronellal treatment indicating the impairment of photosynthetic and respiratory metabolism. Scanning electron microscopic studies in C. occidentalis leaves upon treatment of citronellal revealed disruption of cuticular wax, clogging of stomata and shrinkage of epidermal cells at many places. There was a rapid electrolyte leakage in the leaf tissue upon exposure to citronellal during the initial few hours. In P. minor electrolyte leakage in response to 2 mM citronellal was closer to the maximum leakage that was obtained upon boiling the tissue. The rapid ion leakage is indicative of the severe effect of citronellal on the membrane

  10. Cadmium accumulation in leaves of leafy vegetables.

    PubMed

    Baldantoni, Daniela; Morra, Luigi; Zaccardelli, Massimo; Alfani, Anna

    2016-01-01

    Leafy vegetables have a relatively high potential for Cd uptake and translocation, and are thus considered Cd accumulators. For this reason, leaves and roots of lettuce (Lactuca sativa L.) and endive (Cichorium endivia L.) plants, grown on different agricultural soils in Campania region (southern Italy), subjected to different fertilisation treatments (unfertilisation, compost amendment and mineral fertilisation), were analysed for Cd concentrations. Moreover, to clarify if the highest concentrations found are linked to older and inedible or to younger and edible leaves, external and internal endive leaves were separately analysed. All the leafy vegetables analysed showed on average 2-fold higher Cd concentrations in leaves than in roots. Leaf Cd concentrations in both lettuce and endive plants significantly differed among fertilisation treatments, with values highest in the plants grown on mineral fertilised soils. Apart from the soil fertilisation treatments, however, Cd leaf concentrations were often higher (up to 4-fold) than the threshold deduced by the EU 420/2011 Regulation, although the plants grew on unpolluted soils. Anyway, external leaves of endive plants showed significantly higher concentrations than internal leaves (in some cases the values were 3-fold higher), partly reassuring on the consumption of the younger leaves. Moreover, this study points out two major drawbacks in the Italian and European regulatory frameworks: (1) metal concentration (as total and/or available fraction) limits in agricultural soils are lacking; (2) metal concentration thresholds (currently existing only for Cd and Pb in crops) reported in the EU 420/2011 Regulation, expressed on the fresh weight basis rather than on the dry weight basis, appear not suitable.

  11. Parenthood and Leaving Home in Young Adulthood

    PubMed Central

    Hofferth, Sandra L.; Curtin, Sally C.

    2014-01-01

    With increases in nonmarital fertility, the sequencing of transitions in early adulthood has become even more complex. Once the primary transition out of the parental home, marriage was first replaced by nonfamily living and cohabitation; more recently, many young adults have become parents before entering a coresidential union. Studies of leaving home, however, have not examined the role of early parenthood. Using the Young Adult Study of the 1979 National Longitudinal Survey of Youth (n = 4,674), we use logistic regression to analyze parenthood both as a correlate of leaving home and as a route from the home. We find that even in mid-adolescence, becoming a parent is linked with leaving home. Coming from a more affluent family is linked with leaving home via routes that do not involve children rather than those that do, and having a warm relationship with either a mother or a father retards leaving home, particularly to nonfamily living, but is not related to parental routes out of the home. PMID:25544790

  12. Maize Leaves Turn Away from Neighbors1

    PubMed Central

    Maddonni, Gustavo Angel; Otegui, María Elena; Andrieu, Bruno; Chelle, Michael; Casal, Jorge J.

    2002-01-01

    In commercial crops, maize (Zea mays) plants are typically grown at a larger distance between rows (70 cm) than within the same row (16–23 cm). This rectangular arrangement creates a heterogeneous environment in which the plants receive higher red light (R) to far-red light (FR) ratios from the interrow spaces. In field crops, the hybrid Dekalb 696 (DK696) showed an increased proportion of leaves toward interrow spaces, whereas the experimental hybrid 980 (Exp980) retained random leaf orientation. Mirrors reflecting FR were placed close to isolated plants to simulate the presence of neighbors in the field. In addition, localized FR was applied to target leaves in a growth chamber. During their expansion, the leaves of DK696 turned away from the low R to FR ratio signals, whereas Exp980 leaves remained unaffected. On the contrary, tillering was reduced and plant height was increased by low R to FR ratios in Exp980 but not in DK696. Isolated plants preconditioned with low R/FR-simulating neighbors in a North-South row showed reduced mutual shading among leaves when the plants were actually grouped in North-South rows. These observations contradict the current view that phytochrome-mediated responses to low R/FR are a relic from wild conditions, detrimental for crop yield. PMID:12427985

  13. [Morphogenesis of proximal branch leaves in mosses].

    PubMed

    Ignatov, M S; Spirina, U N

    2012-01-01

    The formation of deeply dissected and compound leaves at the bases of branches, their homology between different groups of mosses, and probable factors responsible for their development are considered. Previous authors differ in the interpretation of such leaves and in most cases describe them as special morphological structures named pseudoparaphyllia. It is shown, however, that this term has been applied both to whole leaves and to separate leaf parts. Among the patterns of leaf formation deviating from the basic type, a special place belongs to the Hampeella variant, where deeply dissected and compound leaves are formed due to the delayed development of branch primordia. The families representing this variant occupy a basal position in the phylogenetic tree of pleurocarpous mosses. The Leucodon variant, where splitting of leaves into lobes is apparently explained by strong stem extension, is not specific for any definite phylogenetic group and manifests itself in different families. The Hypnum variant is also not associated with certain phylogenetic lineages, but it provides an example of more profound specialization.

  14. Maize leaves turn away from neighbors.

    PubMed

    Maddonni, Gustavo Angel; Otegui, María Elena; Andrieu, Bruno; Chelle, Michael; Casal, Jorge J

    2002-11-01

    In commercial crops, maize (Zea mays) plants are typically grown at a larger distance between rows (70 cm) than within the same row (16-23 cm). This rectangular arrangement creates a heterogeneous environment in which the plants receive higher red light (R) to far-red light (FR) ratios from the interrow spaces. In field crops, the hybrid Dekalb 696 (DK696) showed an increased proportion of leaves toward interrow spaces, whereas the experimental hybrid 980 (Exp980) retained random leaf orientation. Mirrors reflecting FR were placed close to isolated plants to simulate the presence of neighbors in the field. In addition, localized FR was applied to target leaves in a growth chamber. During their expansion, the leaves of DK696 turned away from the low R to FR ratio signals, whereas Exp980 leaves remained unaffected. On the contrary, tillering was reduced and plant height was increased by low R to FR ratios in Exp980 but not in DK696. Isolated plants preconditioned with low R/FR-simulating neighbors in a North-South row showed reduced mutual shading among leaves when the plants were actually grouped in North-South rows. These observations contradict the current view that phytochrome-mediated responses to low R/FR are a relic from wild conditions, detrimental for crop yield.

  15. School Involvement Leave: Providing Leave for Parental Involvement in School Activities. Policy Briefing Series. Issue 18

    ERIC Educational Resources Information Center

    Curlew, Mary; Weber, Julie

    2009-01-01

    One of the most important factors in school performance is parental involvement. However, many parents do not have the flexibility in their work schedules or the leave policies necessary to attend school functions. As a result, legislators are creating policies to address this issue. School involvement leave policies provide parents with…

  16. University Students Leaving Relationships (USLR): Scale Development and Gender Differences in Decisions to Leave Romantic Relationships

    ERIC Educational Resources Information Center

    Hendy, Helen M.; Can, S. Hakan; Joseph, Lauren J.; Scherer, Cory R.

    2013-01-01

    The University Students Leaving Relationships scale was developed to identify student concerns when contemplating dissolution of romantic relationships. Participants included 1,106 students who rated the importance of issues when deciding to leave relationships. Factor analysis produced three dimensions: Missing the Relationship, Social…

  17. Uptake of perfluoroalkyl acids in the leaves of coniferous and deciduous broad-leaved trees.

    PubMed

    Zhang, Huanhuan; Liu, Wei; He, Xin; Wang, Yu; Zhang, Qian

    2015-07-01

    Analytical methods for determining perfluoroalkyl acids (PFAAs) in leaves were developed to quantify a suite of analytes in both coniferous and deciduous broad-leaved trees. Sodium hydroxide-methanol and solid-phase extraction was selected as the extracting and cleanup strategy for PFAA analysis. Ten perfluorocarboxylic acids (PFCAs) and 4 perfluorosulfonic acids (PFSAs) were monitored in 7 kinds of leaves grown in the urban areas of Dalian, China. The results show that coniferous tree leaves take up more PFAAs than broad-leaved tree leaves, with the highest amount of 150 ng/g in pine needles. Leaf PFCA levels were much higher than PFSAs level. Short carbon-chain PFCAs with 3 to 6 perfluorinated carbons account for approximately 40% to 80% of the total leaf PFAAs, where uptake decreased with increasing carbon chain length. Temporal observation of leaf PFAAs revealed no significant variation of concentrations in the leaves over a weekly interval and the absence of significant seasonal change in pine needles and sophora. The present study provides some evidence for the accumulation of PFAAs in leaves, which is valuable for understanding their environmental behavior and the development of alternative bioindicator.

  18. 29 CFR 825.207 - Substitution of paid leave.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... that the paid leave provided by the employer, and accrued pursuant to established policies of the... to the employer's applicable paid leave policy during the period of otherwise unpaid FMLA leave. An... employer's normal leave policy. When an employee chooses, or an employer requires, substitution of...

  19. 29 CFR 825.207 - Substitution of paid leave.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... that the paid leave provided by the employer, and accrued pursuant to established policies of the... to the employer's applicable paid leave policy during the period of otherwise unpaid FMLA leave. An... employer's normal leave policy. When an employee chooses, or an employer requires, substitution of...

  20. 38 CFR 21.342 - Leave accounting policy.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2013-07-01 2013-07-01 false Leave accounting policy. 21.342 Section 21.342 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS.... Chapter 31 Leaves of Absence § 21.342 Leave accounting policy. (a) Amount of leave. A veteran pursuing...

  1. 38 CFR 21.342 - Leave accounting policy.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2014-07-01 2014-07-01 false Leave accounting policy. 21.342 Section 21.342 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS.... Chapter 31 Leaves of Absence § 21.342 Leave accounting policy. (a) Amount of leave. A veteran pursuing...

  2. 5 CFR 831.302 - Unused sick leave.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... annuity is increased by the days of unused sick leave to his credit under a formal leave system. (b) An...) A formal leave system is one which is provided by law or regulation or operates under written rules... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Unused sick leave. 831.302 Section...

  3. 5 CFR 630.501 - Annual leave recredit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... annual leave is transferred between different leave systems under section 6308 of title 5, United States Code, or is recredited under a different leave system as the result of a refund under section 6306 of... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Annual leave recredit. 630.501...

  4. 5 CFR 630.1210 - Greater leave entitlements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AND LEAVE Family and Medical Leave § 630.1210 Greater leave entitlements. (a) An agency shall comply... greater family or medical leave entitlements to employees than those provided under this subpart. Nothing... or regulation. (d) The entitlements under sections 6381 through 6387 of title 5, United States...

  5. 38 CFR 21.342 - Leave accounting policy.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Leave accounting policy. 21.342 Section 21.342 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS.... Chapter 31 Leaves of Absence § 21.342 Leave accounting policy. (a) Amount of leave. A veteran pursuing...

  6. Why Promotable Female Officers Leave the Army

    DTIC Science & Technology

    1993-07-01

    34AD-A268 946 Study l Report 93-04 Why Promotable Female Officers Leave the Army Alma G. Steinberg, Beverly C. Harris, and Jacquelyn Scarville U.S...DATE 3 REPORT TYPE AND DATES COVERED I 1993, July Final Jul 92 - Oct 92 4 TITLE AND SUBTITLE S. FUNDING NUMBERS ;T,’hy Promotable Female Officers Leave...13. ABSTRACT (Maximuhm 200 words) This paper presents the findings of a study designed to identify the reasons female Captains who were eligible for

  7. Arylsulfonate-Based Nucleophile Assisting Leaving Groups

    PubMed Central

    Lepore, Salvatore D.; Bhunia, Anjan K.; Cohn, Pamela

    2013-01-01

    The synthesis and unique reactivity of a series of arylsulfonate-based nucleophile assisting leaving groups (NALG) containing oligomeric ether units (including crown ethers) attached to the arylsulfonyl ring in the ortho orientation are described. The reactions of a variety of these ether-containing alkyl sulfonates with metal halides proceeded at substantially greater rates than electronically similar sulfonates. These ether-containing leaving groups also displayed marked selectivity for lithium halides relative to the corresponding sodium and potassium salts in nucleophilic displacement reactions. PMID:16277337

  8. Leaving Welfare: Independence or Continued Vulnerability?

    ERIC Educational Resources Information Center

    Litt, Jacquelyn; Gaddis, Barbara J.; Fletcher, Cynthia Needles; Winter, Mary

    2000-01-01

    Interviews with seven women before and 6 months after leaving welfare revealed barriers to self-sufficiency (low wages, lack of advancement opportunities in jobs, confusion about program regulations) and survival strategies (continued reliance on income and family support, banking of care benefits under the 5-year limit as a safety net). (SK)

  9. Sabbatical Leave: Who Gains and How Much?

    ERIC Educational Resources Information Center

    Davidson, Oranit B.; Eden, Dov; Westman, Mina; Cohen-Charash, Yochi; Hammer, Leslie B.; Kluger, Avraham N.; Krausz, Moshe; Maslach, Christina; O'Driscoll, Michael; Perrewe, Pamela L.; Quick, James Campbell; Rosenblatt, Zehava; Spector, Paul E.

    2010-01-01

    A rigorous quasi-experiment tested the ameliorative effects of a sabbatical leave, a special case of respite from routine work. We hypothesized that (a) respite increases resource level and well-being and (b) individual differences and respite features moderate respite effects. A sample of 129 faculty members on sabbatical and 129 matched controls…

  10. Why Do Students Leave the University? Draft.

    ERIC Educational Resources Information Center

    Curran, Jay; And Others

    Student withdrawal from the University of Iowa was studied using an exit survey. Students' reasons for leaving the university, their future plans, and possible interventions that would have assisted the student to remain in school were assessed, along with the validity of the survey. Although there was only 62 percent agreement between the exit…

  11. Geometric Probability and the Areas of Leaves

    ERIC Educational Resources Information Center

    Hoiberg, Karen Bush; Sharp, Janet; Hodgson, Ted; Colbert, Jim

    2005-01-01

    This article describes how a group of fifth-grade mathematics students measured irregularly shaped objects using geometric probability theory. After learning how to apply a ratio procedure to find the areas of familiar shapes, students extended the strategy for use with irregularly shaped objects, in this case, leaves. (Contains 2 tables and 8…

  12. Leave no trace in the outdoors

    USGS Publications Warehouse

    Marion, Jeffrey L.

    2014-01-01

    The essential guide for enjoying the outdoors without harming the environment. - Details the seven core principles of Leave No Trace ethics and practices - Covers hiking, campfires, food storage, and personal hygiene - Endorsed by the USDI National Park Service, Bureau of Land Management, Fish & Wildlife Service, U.S. Geological Survey, and the USDA Forest Service

  13. Ladybugs and Lettuce Leaves. Teachers' Manual.

    ERIC Educational Resources Information Center

    Barnes, Tracy; And Others

    This is a guide for use with "Ladybugs and Lettuce Leaves" activity cards which are activities for elementary school students (grades 4 to 6) focusing on gardening. It includes educational objectives for each topic as well as lists of vocabulary words, comments, questions for discussion, additional activities, and resources. An interdisciplinary…

  14. Sun and Shade Leaves: Some Field Investigations.

    ERIC Educational Resources Information Center

    Tomley, David

    1983-01-01

    Several simple experiments illustrating how the light regime affects the final form of dog's mercury (Mercurialis perennis) are provided. These experiments, which can also be done with other plants, focus on differences in the anatomy, morphology, and physiology of sun and shade leaves. (JN)

  15. Diterpenoids from Leaves of Rubus chingii.

    PubMed

    Shu, Jicheng; Huang, Yingzheng; Cui, Hangqing; Peng, Caiying; Liu, Jianqun; Huang, Huilian

    2016-03-01

    The leaves of Rubus chingii were examined for their phytochemical composition and anti-yeast activity. In the process, seven diterpenoids (compounds 1-7), including a new natural compound (14β, 16-epoxy-7-pimarene-3α, 15β-diol, 1), were isolated and elucidated. Compound 1 exhibited moderate anti-Candida activity.

  16. The Biology of Ageing in Leaves.

    ERIC Educational Resources Information Center

    Gill, John; And Others

    1988-01-01

    Describes laboratory procedures for observing the progressive change deciduous leaves undergo prior to abscission. Outlines the starch test, sugar test, extraction and chromatography of pigments, and experimental results. States that obtained results enable the events of leaf senescence to be correlated with the carbohydrate economy of a tree in…

  17. Ecojustice in Science Education: Leaving the Classroom

    ERIC Educational Resources Information Center

    Mueller, Michael P.

    2011-01-01

    Eduardo Dopico and Eva Garcia-Vazquez's article enriched the ecojustice literature with an interesting metaphor of leaving the classroom, which I argue for here. Glasson and Boggs help to highlight the challenges and fortitude of working ecojustice perspectives in science education and the ways that a dialogical conversation addresses the world at…

  18. Leaving Care: The Need to Make Connections

    ERIC Educational Resources Information Center

    Coyle, Deirdre; Pinkerton, John

    2012-01-01

    For too many years the phrase "after care, an after thought" summed up the lack of attention given to preparing young people in care for adult life and to the development of leaving-care and aftercare services. That stance has changed in the United Kingdom, however, and indeed has shifted positively and dramatically over the last decade.…

  19. Practical Approaches for Teaching Leave No Trace.

    ERIC Educational Resources Information Center

    Attarian, Aram

    As participation in outdoor recreation grows, natural resources suffer a variety of environmental and social impacts. A minimum-impact back country educational program first developed during the 1970s, Leave No Trace (LNT), has been revitalized by the National Outdoor Leadership School, six federal agencies, and members of the outdoor products…

  20. 29 CFR 825.205 - Increments of FMLA leave for intermittent or reduced schedule leave.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... commence or end work mid-way through a shift, such as where a flight attendant or a railroad conductor is... leave at any particular hourly rate. An eligible employee is entitled to up to a total of 12...

  1. Atmospheric ammonia: absorption by plant leaves.

    PubMed

    Hutchinson, G L; Millington, R J; Peters, D B

    1972-02-18

    By monitoring the disappearance of ammonia from an airstream flowing through a small growth chamber containing a single plant seedling, it was discovered that plant leaves absorb significant quantities of ammonia from the air, even at naturally occurring low atmospheric concentrations. The measured absorption rates of ammonia showed large diurnal fluctuations and varied somewhat among species, but differed little with the nitrogen fertility level of plants within a species.

  2. Constituents of the leaves of Verbascum blattaria.

    PubMed

    Youn, I-Soo; Han, Ah-Reum; Roh, Mark S; Seo, Eun-Kyoung

    2015-03-01

    Phytochemical investigation of the dried leaves of Verbascum blattaria L. (Scrophulariaceae) led to the isolation and identification of five known compounds, E-harpagoside, laterioside, kaempferol 3-O-β-D-glucopyranoside, bis(2-ethylhexyl)phthalate, and (2S)-liquiritigenin. The structures of these compounds were determined by physical and spectroscopic data analysis. All compounds were isolated from V blattaria for the first time.

  3. A new sesquiterpene lactone from yacon leaves.

    PubMed

    Yuan, Ying; Win Aung, Khin Khin; Ran, Xiao-Ku; Wang, Xiao-Tong; Dou, De-Qiang; Dong, Feng

    2017-01-01

    The chemical constituents of 60% EtOH extract of yacon leaves were separated to yield a new compound, together with four known compounds, which were isolated for the first time from yacon. The new compound was characterised and named as chlorodalin (1) on the basis of NMR (1D and 2D), HR-MS and other spectral methods. The cytotoxic activities of 1-5 were evaluated on two human tumour cell lines and the new compound showed significant cytotoxic activity.

  4. Morphology of leaves cuticle by fringe projection

    NASA Astrophysics Data System (ADS)

    Martínez, Amalia; Rayas Alvarez, J. A.; Cordero, Raúl; Balieiro R., Daniela

    2011-10-01

    The development of this work is important in the morphological study of plant parts, specifically in the study of the cuticle of fruits or leaves. The implemented optical technique for fringe projection can identify potential fracture zones which damage the presentation of the fruits impacting business as well as producing them. Specifically, we obtained information on the thickness of a cuticle corresponding to the abaxial surface of a leaf of apple (Malus domestica) of the variety Golden Delicious.

  5. Sick leave patterns in common musculoskeletal disorders – a study of doctor prescribed sick leave

    PubMed Central

    2014-01-01

    Background Comparative data on sick leave within musculoskeletal disorders (MSDs) is limited. Our objective was to give a descriptive overview of sick leave patterns in different MSDs. Methods Using electronic medical records, we collected information on dates and diagnostic codes for all available sick leave certificates, during 2 years (2009–2010), in the North Western part of the Skåne region in Sweden (22 public primary health care centres and two general hospitals). Using the International Classification of Diseases (ICD) 10 codes on the certificates we studied duration, age and sex distribution and recurrent periods of sick leave for six strategically chosen MSDs; low back pain (M54) disc disorders (M51), knee osteoarthritis (M17) hip osteoarthritis (M16) rheumatoid arthritis (M05-M06) and myalgia (M79). Results All together 20 251 sick leave periods were issued for 16 673 individuals 16–64 years of age (53% women). Out of the selected disorders, low back pain and myalgia had the shortest sick leave periods, with a mean of 26 and 27 days, respectively, while disc disorders and rheumatoid arthritis had the longest periods with a mean of 150 and 147 days. For low back pain and myalgia 27% and 26% of all sick leave was short (8–14 days) and only 11% and 13%, were long (≥90 days). For the other selected MSDs, less than 5% of the periods were short. For disc disorders, hip osteoarthritis and rheumatoid arthritis, more than 60% of the periods were long (p > 0.001). For back disorders and myalgia most periods were issued in the age groups between 40–49, with similar patterns for women and men. Osteoarthritis and rheumatoid arthritis had most periods in the age groups of 50–64, and patterns for women and men differed. Low back pain, rheumatoid arthritis and myalgia had the greatest share of recurrent sick leave (31%, 34% and 32% respectively). Conclusion Duration, age and sex distribution and numbers of recurrent sick leave varies considerably

  6. The cost of sickness: on the effect of the duration of sick leave on post-sick leave earnings.

    PubMed

    Andersen, Signe Hald

    2010-05-01

    Studies analysing the effect of the duration of sick leave on subsequent labour market outcomes do not consider the potential endogenous relationship between duration and labour market outcomes. This paper deals with this shortcoming by using a consistent estimator attained through Instrumental Variables methods for estimating the effect of the duration of a sick leave spell on post-sick leave earnings. I use Danish administrative data and a major 2001 reform of the sick leave system as the instrument for duration. I find that the duration of a sick leave spell has both short and long term effects on post-sick leave earnings.

  7. 38 CFR 21.6340 - Leaves of absence.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 21.6074. Leave may only be authorized for a veteran during a period of rehabilitation to the point of employability. (Authority: 38 U.S.C. 1524(b)) (b) Purpose. The purpose of the leave system is to enable...

  8. Interaction of Salmonella enterica with Fresh Produce Leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Attachment and colonization of Salmonella enterica serovars to fresh produce leaves was investigated. Biofilm assay and attachment of Salmonella serovars to intact and cut leaves were determined. Salmonella Tennessee and Salmonella Thompson produced stronger biofilms compared to Salmonella Newpor...

  9. 29 CFR 825.301 - Designation of FMLA leave.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the employer's failure to timely designate leave does not cause harm or injury to the employee. In all... alternative caregiver for the seriously-ill son or daughter if the leave had been designated timely....

  10. Keep on growing: building and patterning leaves in the grasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Monocot leaves have unique features that arise early in their development. Maturing leaves protectively enclose younger leaves and the meristem, the pool of founder cells from which a leaf emerges. Through the maturation process, proximal sheath and distal blade tissues differentiate and are separat...

  11. Why Band Directors Leave: From the Mouths of Maestros

    ERIC Educational Resources Information Center

    Scheib, John W.

    2004-01-01

    This article discusses the results of a survey conducted by the author asking music teachers why they leave their jobs. The author compiled an e-mail survey and sent it to instrumental music teachers who were making plans to leave their jobs for new positions or to leave the music education profession entirely. In order to widen the pool of…

  12. 5 CFR 630.911 - Restoration of transferred annual leave.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Restoration of transferred annual leave. 630.911 Section 630.911 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Transfer Program § 630.911 Restoration of transferred...

  13. 5 CFR 630.911 - Restoration of transferred annual leave.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Restoration of transferred annual leave. 630.911 Section 630.911 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Transfer Program § 630.911 Restoration of transferred...

  14. 5 CFR 630.911 - Restoration of transferred annual leave.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Restoration of transferred annual leave. 630.911 Section 630.911 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Transfer Program § 630.911 Restoration of transferred...

  15. 5 CFR 630.911 - Restoration of transferred annual leave.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Restoration of transferred annual leave. 630.911 Section 630.911 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Transfer Program § 630.911 Restoration of transferred...

  16. 5 CFR 630.911 - Restoration of transferred annual leave.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Restoration of transferred annual leave. 630.911 Section 630.911 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Transfer Program § 630.911 Restoration of transferred...

  17. 5 CFR 630.402 - Requesting sick leave.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... employee must request advance approval for sick leave for the purpose of receiving medical, dental, or... user, the added text is set forth as follows: § 630.402 Advanced sick leave. (a) At the beginning of a... grant advanced sick leave in the amount of: (1) Up to 240 hours to a full-time employee— (i) Who...

  18. 48 CFR 752.7031 - Leave and holidays.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... (e) Military leave. Military leave of not more than 15 calendar days in any calendar year may be... not limited to 1 year or less and who is a reservist of the United States Armed Forces, provided that such military leave has been approved in advance by the cognizant Mission Director or...

  19. 5 CFR 630.208 - Reduction in leave credits.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Reduction in leave credits. 630.208... credits. (a) When the number of hours in a nonpay status in a full-time employee's leave year equals the number of basepay hours in a pay period, the agency shall reduce his credits for leave by an amount...

  20. 5 CFR 630.208 - Reduction in leave credits.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Reduction in leave credits. 630.208... credits. (a) When the number of hours in a nonpay status in a full-time employee's leave year equals the number of basepay hours in a pay period, the agency shall reduce his credits for leave by an amount...

  1. Sabbatical Leave for Teachers. PAR Analysis Number 211.

    ERIC Educational Resources Information Center

    Public Affairs Research Council of Louisiana, Inc., Baton Rouge.

    Louisiana's sabbatical leave law for public school teachers and state college faculty is one of the most liberal in the nation. Teachers are granted the right to sabbatical leave for purposes of professional or cultural development, and for rest and recuperation. While on leave, they receive partial salary compensation. The state of Louisiana…

  2. Self-Funded Leave and Life Role Development

    ERIC Educational Resources Information Center

    Furbish, Dale S.

    2009-01-01

    Self-funded leave is an employee benefit that provides a time resource to those who wish to develop interests and other life roles. Semistructured interviews were used for this qualitative study to explore the motivations for enrolling in the self-funded leave program, how the leave contributed to work-life balance through development of other…

  3. 38 CFR 21.8340 - Leaves of absence.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) VOCATIONAL REHABILITATION AND EDUCATION Vocational Training and Rehabilitation for Certain Children of...) Purpose of leave of absence. The purpose of the leave system is to enable the child to maintain his or her... absence. The VR&E case manager may grant the child leaves of absence for periods during which the...

  4. 29 CFR 825.310 - Certification for leave taken to care for a covered servicemember (military caregiver leave).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee and Employer Rights and Obligations Under the Act § 825.310 Certification for leave taken to...

  5. 29 CFR 825.310 - Certification for leave taken to care for a covered servicemember (military caregiver leave).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee and Employer Rights and Obligations Under the Act § 825.310 Certification for leave taken to...

  6. 29 CFR 825.310 - Certification for leave taken to care for a covered servicemember (military caregiver leave).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... servicemember (military caregiver leave). 825.310 Section 825.310 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993... for a covered servicemember (military caregiver leave). (a) Required information from health...

  7. 29 CFR 825.310 - Certification for leave taken to care for a covered servicemember (military caregiver leave).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... servicemember (military caregiver leave). 825.310 Section 825.310 Labor Regulations Relating to Labor (Continued... for a covered servicemember (military caregiver leave). (a) Required information from health care provider. When leave is taken to care for a covered servicemember with a serious injury or illness,...

  8. Antinociceptive activity of Ricinus communis L. leaves

    PubMed Central

    Taur, Dnyaneshwar J; Waghmare, Maruti G; Bandal, Rajendra S; Patil, Ravindra Y

    2011-01-01

    Objective To evaluate the antinociceptive activity of the methanol extract of Ricinus communis leaves (MRCL). Methods Antinociceptive activity was evaluated using acetic acid induced writhing test, formalin induced paw licking and tail immersion method in mice at doses of 100, 125 and 150 mg/kg bw. Results The results indicated that MRCL exhibited considerable antinociceptive activity against three classical models of pain in mice. Preliminary phytochemical analysis suggested the presence of saponin, steroids and alkaloids. Conclusions It can be concluded that MRCL possesses antinociceptive potential that may be due to saponin, steroids and alkaloids in it. PMID:23569744

  9. [Chemical constituents from leaves of Ilex latifolia].

    PubMed

    Wang, Cun-Qin; Wang, Lei; Li, Bao-Jing; Fan, Chun-Lin; Huang, Xiao-Jun; Ye, Wen-Cai

    2014-01-01

    Nine compounds were isolated from the leaves of Ilex latifolia. Their structures were respectively identified as 5-hydroxy-6, 7, 8, 4'-tetramethoxyflavone (1), tangeretin (2), nobiletin (3), 5-hydroxy-6, 7, 8, 3', 4'-pentamethoxyflavone (4), 5, 6, 7, 8, 4'-pentamethoxyflavonol (5), 5, 6, 7, 8, 3', 4'-hexamethoxy-flavonol (6), 5-hydroxy-3', 4', 7-trimethoxyflavanone (7), soyacerebroside I (8), and soyacerebroside II (9) by their physicochemical properties and spectroscopic data Compounds 1-9 were isolated from this plant for the first time.

  10. Evolutionary biology. Chewed leaves reveal ancient relationship.

    PubMed

    Pennisi, E

    2000-07-14

    On page 291, researchers describe a new beetle fossil based not on traces of the insect skeleton but on the distinctive gouges the beetles left when they munched on 11 ginger leaves many millions of years ago. The chew marks of the newly described Cephaloleichnites strongi prove that leaf beetles underwent rapid evolution and diversification more than 65 million years ago, possibly taking advantage of (and perhaps influencing) the rapid diversification among flowering plants occurring at the same time. What's more, C. strongi represents the earliest known rolled-leaf beetle species, hundreds of which today still prefer just one of the ginger- and heliconia-like plants in the Zingiberales order.

  11. Reconfiguration of broad leaves into cones

    NASA Astrophysics Data System (ADS)

    Miller, Laura

    2013-11-01

    Flexible plants, fungi, and sessile animals are thought to reconfigure in the wind and water to reduce the drag forces that act upon them. Simple mathematical models of a flexible beam immersed in a two-dimensional flow will also exhibit this behavior. What is less understood is how the mechanical properties of a leaf in a three-dimensional flow will passively allow roll up and reduce drag. This presentation will begin by examining how leaves roll up into drag reducing shapes in strong flow. The dynamics of the flow around the leaf of the wild ginger Hexastylis arifolia are described using particle image velocimetry. The flows around the leaves are compared with those of simplified sheets using 3D numerical simulations and physical models. For some reconfiguration shapes, large forces and oscillations due to strong vortex shedding are produced. In the actual leaf, a stable recirculation zone is formed within the wake of the reconfigured cone. In physical and numerical models that reconfigure into cones, a similar recirculation zone is observed with both rigid and flexible tethers. These results suggest that the three-dimensional cone structure in addition to flexibility is significant to both the reduction of vortex-induced vibrations and the forces experienced by the leaf.

  12. Superexpression of tuberculosis antigens in plant leaves.

    PubMed

    Dorokhov, Yuri L; Sheveleva, Anna A; Frolova, Olga Y; Komarova, Tatjana V; Zvereva, Anna S; Ivanov, Peter A; Atabekov, Joseph G

    2007-05-01

    Recent developments in genetic engineering allow the employment of plants as factories for 1/foreign protein production. Thus, tuberculosis (TB) ESAT6 antigen was expressed in different plant systems, but the level of vaccine protein accumulation was extremely low. We describe the technology for superexpression of TB vaccine proteins (Ag85B, ESAT6, and ESAT6:Ag85B fusion) in plant leaves which involves: (i) construction of tobacco mosaic virus-based vectors with the coat protein genes substituted by those for TB antigens; (ii) Agrobacterium-mediated delivery to plant leaf tissues of binary vectors containing the cDNA copy of the vector virus genome; and (iii) replication of virus vectors in plant cells under conditions suppressing the virus-induced gene silencing. This technology enables efficient production of the TB vaccine proteins in plants; in particular, the level of Ag85B antigen accumulation was not less than 800 mg/kg of fresh leaves. Expression of TB antigens in plant cells as His(6)-tagged proteins promoted their isolation and purification by Ni-NTA affinity chromatography. Deletion of transmembrane domains from Ag85B caused a dramatic increase in its intracellular stability. We propose that the strategy of TB antigens superproduction in a plant might be used as a basis for the creation of prophylactic and therapeutic vaccine against TB.

  13. Immunostimulant effects of Capparis zeylanica Linn. leaves.

    PubMed

    Ghule, B V; Murugananthan, G; Nakhat, P D; Yeole, P G

    2006-11-24

    The present study was undertaken to explore the immunomodulatory activity of ethanolic and water extracts of Capparis zeylanica Linn. (family: Capparidaceae) leaves on neutrophil adhesion test, humoral response to sheep red blood cells, delayed-type hypersensitivity, phagocytic activity and cyclophosphamide-induced myelosuppression. Pre-treatment of water extract (300 mg/kg, oral) of Capparis zeylanica evoked a significant increase in neutrophil adhesion to nylon fibres. The augmentation of humoral immune response to sheep red blood cells by ethanolic and water extracts (150-300 mg/kg) is evidenced by increase in antibody titres in mice. A dose-related increase in both primary and secondary antibody titre was observed. Oral administration of ethanolic and water extracts of Capparis zeylanica leaves, at doses of 150 and 300 mg/kg in mice, dose dependently potentiated the delayed-type hypersensitivity reaction induced by sheep red blood cells. Immunomodulatory activity was also assessed by serological and haematological tests. Capparis zeylanica extracts prevented myelosuppression in mice treated with cyclophosphamide drug. The study comprised the acute toxicity and preliminary phytochemical screening of the ethanol and water extracts.

  14. Biophotonic in situ sensor for plant leaves

    SciTech Connect

    Conejo, Elian; Frangi, Jean-Pierre; Rosny, Gilles de

    2010-04-01

    Knowledge of the water concentration of plants can be helpful in several environmental and agricultural domains. There are many methods for the determination of water content in plant leaves; however, most of them give a relative moisture level or an analytical measure after a previous calibration procedure. Even for other biochemical compounds such as dry matter or chlorophyll, the measurement techniques could be destructive. For this reason, a nondestructive method has been developed to measure the biochemical compounds of a plant leaf, using an infrared spectroscopy technique. One important advantage is the simplicity of the device (RAdiometre portatif de Mesure In Situ, RAMIS) and its capability to perform measurements in situ. The prototype is a leaf-clip configuration and is made of LEDs at five wavelengths (656, 721, 843, 937, and 1550 nm), and a silicon/germanium photosensor. To compute the water content of vegetative leaves, the radiative transfer model PROSPECT was implemented. This model can accurately predict spectral transmittances in the 400 nm to 2500 nm spectral region as a function of the principal leaf biochemical contents: water, dry matter, and chlorophyll. Using the transmittance measured by RAMIS into an inversion procedure of PROSPECT: A Model of Leaf Optical Properties Spectra, we are able to compute the values of water contents that show an agreement with the water contents measured directly using dry weight procedures. This method is presented as a possibility to estimate other leaf biochemical compounds using appropriate wavelengths.

  15. Synthetic Leaves: Pumping at Negative Pressures

    NASA Astrophysics Data System (ADS)

    Wheeler, Tobias; Stroock, Abraham; Havenstrite, Karen

    2004-03-01

    A common process that is rarely considered in detail is the circulation of fluid in trees. As with most multi-cellular organisms, the internal convective transport of nutrients and the evacuation of waste are essential to their survival. What is unique to flowering plants is that the convectively transported fluid (water) is under tension. According to the Cohesion-Tension Theory (Dixon & Joly), this tension is induced by siphoning: capillary forces replenish water lost to evaporation at the air-water interface in leaves. Intermolecular forces between water molecules ensure that the column of water suspended from the air-water interface remains continuous. Integral to this passive pumping is a dynamic meniscus, which changes curvature and thereby the capillary pressure at the interface to allow the leaf to pump against variable loads as environmental conditions (convection, relative humidity) change. I will present our efforts to harness the capabilities of dynamic menisci in a synthetic system. We use hydraulic resistances as loads to assess the pumping ability of these systems and their susceptibility to cavitation. The goal is to understand the physico-chemical aspects of pumping in plants and the design constraints of vascular networks of leaves.

  16. Ecojustice in science education: leaving the classroom

    NASA Astrophysics Data System (ADS)

    Mueller, Michael P.

    2011-06-01

    Eduardo Dopico and Eva Garcia-Vázquez's article enriched the ecojustice literature with an interesting metaphor of leaving the classroom, which I argue for here. Glasson and Boggs help to highlight the challenges and fortitude of working ecojustice perspectives in science education and the ways that a dialogical conversation addresses the world at large rather than focusing narrowly and exclusively on science education. Considering the metaphor of `leaving the classroom' I want to explore the tensions that can be experienced by science educators who do research focused on ecosocial justice. While it is not a new idea to suggest that there are gatekeepers in science education who try to maintain what counts in terms of impact in the classroom and what counts or not for the purposes of doing good work in science education, I anticipate highlighting the tensions that ecojustice educators may experience and why they can and should persevere with the incisive work that they are doing to conserve the prospects of future generations. Ecojustice no longer belongs constrained under the confines of environmental sciences or environmental education in science education. It is a separate and distinct field of study that should be generally accepted for the ways it brings clarity and conversation to ideas, curriculum studies, and thick descriptions of how people engage in eco-justice and ethics.

  17. Bioactivities examination of Cinchona leaves ethanol extracts

    NASA Astrophysics Data System (ADS)

    Artanti, Nina; Udin, Linar Z.; Hanafi, M.; Jamilah, Kurniasih, Ida Rahmi; Primahana, Gian; Anita, Yulia; Sundowo, Andini; Kandace, Yoice Sri

    2017-01-01

    Cinchona species especially the barks are commonly known for commercial production of quinine as antimalarial. Although it is also reported for treatment of depurative, whooping cough, influenza and dysentery. In this paper we reported in vitro examination of other bioactivities (antidiabetes, antioxidant and in vitro cytotoxicity) of 70% ethanol extract of Cinchona ledgeriana and C. succirubra leaves as well as qunine, quinidine, and cinchonine the major alkaloids found in Cinchona species. Antidiabetes was conducted using α-glucosidase inhibitory activity assay. Antioxidant was conducted using DPPH free radical scavenging activity assay. In vitro cytotoxic activity was concucted by microscopic observation on growth of breast cancer cell line MCF-7. The results showed that at concentration of 100 µg/ml, C. ledgeriana leaves ethanol extracts showed the best activity as antidiabetes (98% inhibitory of α-glucosidase activity) and antioxidant (92% DPPH free radical scavenging activity), whereas at the same concentration C. succirubra, quinine, quinidine and cinchonine showed very low activities of antidiabetes and antioxidant. Microscopic observation of in vitro cytotoxicity showed that C. ledgeriana also has excellent cytotoxicity to breast cancer cell line MCF-7 which better than quinine, quinidine and cinchonine, whereas C. succirubra showed low cytotoxicity. These results suggest that cinchona species have many potential as the source of drugs discovery and development other than just for malaria treatment. Therefore it is important to conduct further studies and to maintain the available Cinchona plantation in Indonesia.

  18. 29 CFR 825.202 - Intermittent leave or reduced leave schedule.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... period of six months, such as for chemotherapy. A pregnant employee may take leave intermittently for... serious health condition and is not strong enough to work a full-time schedule. (2) Intermittent or... schedule reduction might occur, for example, where an employee, with the employer's agreement, works...

  19. 29 CFR 825.202 - Intermittent leave or reduced leave schedule.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... period of six months, such as for chemotherapy. A pregnant employee may take leave intermittently for... serious health condition and is not strong enough to work a full-time schedule. (2) Intermittent or... schedule reduction might occur, for example, where an employee, with the employer's agreement, works...

  20. 29 CFR 825.202 - Intermittent leave or reduced leave schedule.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... period of six months, such as for chemotherapy. A pregnant employee may take leave intermittently for... serious health condition and is not strong enough to work a full-time schedule. (2) Intermittent or... schedule reduction might occur, for example, where an employee, with the employer's agreement, works...

  1. Environmental controls over methanol emission from leaves

    NASA Astrophysics Data System (ADS)

    Harley, P.; Greenberg, J.; Niinemets, É.; Guenther, A.

    2007-12-01

    Methanol is found throughout the troposphere, with average concentrations second only to methane among atmospheric hydrocarbons. Proposed global methanol budgets are highly uncertain, but all agree that at least 60% of the total source arises from the terrestrial biosphere and primary emissions from plants. However, the magnitude of these emissions is also highly uncertain, and the environmental factors which control them require further elucidation. Using a temperature-controlled leaf enclosure, we measured methanol emissions from leaves of six plant species by proton transfer reaction mass spectrometry, with simultaneous measurements of leaf evapotranspiration and stomatal conductance. Rates of emission at 30°C varied from 0.2 to 38 μg g (dry mass)-1 h-1, with higher rates measured on young leaves, consistent with the production of methanol via pectin demethylation in expanding foliage. On average, emissions increased by a factor of 2.3 for each 10°C increase in leaf temperature. At constant temperature, emissions were also correlated with co-varying incident photosynthetic photon flux density and rates of stomatal conductance. The data were analyzed using the emission model developed by Niinemets and Reichstein (2003a, b), with the incorporation of a methanol production term that increased exponentially with temperature. It was concluded that control of emissions, during daytime, was shared by leaf temperature and stomatal conductance, although rates of production may also vary diurnally in response to variations in leaf growth rate in expanding leaves. The model, which generally provided reasonable simulations of the measured data during the day, significantly overestimated emissions on two sets of measurements made through the night, suggesting that production rates of methanol were reduced at night, perhaps because leaf growth was reduced or possibly through a direct effect of light on production. Although the short-term dynamics of methanol emissions can

  2. Steroids from Dysoxylum grande (Meliaceae) leaves.

    PubMed

    Wah, Low Kok; Abas, Faridah; Cordell, Geoffrey A; Ito, Hideyuki; Ismail, Intan Safinar

    2013-02-01

    Seven new 23-oxo-cholestane derivatives named as grandol A (1), B (2), C (3), D (4), E (5), F (6), and G (7) were isolated from Dysoxylum grande leaves alongside with a new 3,4-secodammar-4(28)-en-3-oic acid derivative (8). The structures of the compounds were elucidated based on the interpretation of spectroscopic data, and their relative configurations were established by NOESY 2D NMR data. All of the isolates were tested for anti-acetylcholinesterase activity using thin layer chromatography (TLC)-bioautography with fast blue B salt. Only grandol A (1) and B (2) showed positive results, with clear discoloration at a concentration of 12.5 ppm. However, the obtained IC(50) values for grandol A and B, when using Ellman's method, were not significant (>200 μg/ml).

  3. New jacaranone glucoside from Jacaranda oxyphylla leaves.

    PubMed

    Pereira, V V; Duarte, L P; Silva, R R; Takahashi, J A

    2016-11-01

    Jacaranda oxyphylla Cham. is popularly known as 'caroba-de-São-Paulo' and it is used in traditional medicine for microbial infections. A new phytoquinoid (α/β-glucoside-4-phenylacetate-6-(1-hydroxy-4-oxo-2,5-cyclohexadiene-1-acetate) (1) was isolated from J. oxyphylla leaves, together with three known compounds: quercetin-3-O-β-d-galactoside (2), verbascoside (3) and polystyrene (4). Their chemical structures were elucidated using spectroscopic techniques and by comparison with the related known compounds. In addition, it was found a pronounced acetylcholinesterase inhibitory activity for the quinoid 1 (100.0 ± 0.8%) and phenolic compounds 2 and 3 (99.9 ± 0.7 and 99.3 ± 0.5%, respectively), if compared to the standard eserine (92.7 ± 0.4%), that was analysed by a microplate spectrophotometer.

  4. Volatile organic compounds from leaves litter.

    PubMed

    Isidorov, Valery; Jdanova, Maria

    2002-09-01

    Qualitative composition of volatile emissions of litter of five species of deciduous trees was investigated by GC-MS. The list of identified substances contains more than 70 organic compounds of various classes. It was established that the composition of components emitted by the litter into the gas phase greatly differs from that of essential oils extracted by hydrodistillation from turned leaves collected from trees during fall. It is suggested that most compounds found in litter emissions are products of vital activity of microorganisms decomposing it. The reported data indicate that after the vegetative period is over the decomposition processes of litter are important seasonal sources of reactive organic compounds under the forest canopy.

  5. Volume penalization to model falling leaves

    NASA Astrophysics Data System (ADS)

    Kolomenskiy, Dmitry; Schneider, Kai

    2007-11-01

    Numerical modeling of solid bodies moving through viscous incompressible fluid is considered. The 2D Navier-Stokes equations, written in the vorticity-streamfunction formulation, are discretized using a Fourier pseudo-spectral scheme with adaptive time-stepping. Solid obstacles of arbitrary shape are taken into account using the volume penalization method. Time- dependent penalization is implemented, making the method capable of solving problems where the obstacle follows an arbitrary motion. Numerical simulations of falling leaves are performed, using the above model supplemented by the discretized ODEs describing the motion of a solid body subjected to external forces and moments. Various regimes of the free fall are explored, depending on the physical parameters and initial conditions. The influence of the Reynolds number on the transition between fluttering and tumbling is investigated, showing the stabilizing effect of viscosity.

  6. Photoperiodic flowering: time measurement mechanisms in leaves.

    PubMed

    Song, Young Hun; Shim, Jae Sung; Kinmonth-Schultz, Hannah A; Imaizumi, Takato

    2015-01-01

    Many plants use information about changing day length (photoperiod) to align their flowering time with seasonal changes to increase reproductive success. A mechanism for photoperiodic time measurement is present in leaves, and the day-length-specific induction of the FLOWERING LOCUS T (FT) gene, which encodes florigen, is a major final output of the pathway. Here, we summarize the current understanding of the molecular mechanisms by which photoperiodic information is perceived in order to trigger FT expression in Arabidopsis as well as in the primary cereals wheat, barley, and rice. In these plants, the differences in photoperiod are measured by interactions between circadian-clock-regulated components, such as CONSTANS (CO), and light signaling. The interactions happen under certain day-length conditions, as previously predicted by the external coincidence model. In these plants, the coincidence mechanisms are governed by multilayered regulation with numerous conserved as well as unique regulatory components, highlighting the breadth of photoperiodic regulation across plant species.

  7. Medicinal properties of neem leaves: a review.

    PubMed

    Subapriya, R; Nagini, S

    2005-03-01

    Azadirachta indica, commonly known as neem, has attracted worldwide prominence in recent years, owing to its wide range of medicinal properties. Neem has been extensively used in Ayurveda, Unani and Homoeopathic medicine and has become a cynosure of modern medicine. Neem elaborates a vast array of biologically active compounds that are chemically diverse and structurally complex. More than 140 compounds have been isolated from different parts of neem. All parts of the neem tree- leaves, flowers, seeds, fruits, roots and bark have been used traditionally for the treatment of inflammation, infections, fever, skin diseases and dental disorders. The medicinal utilities have been described especially for neem leaf. Neem leaf and its constituents have been demonstrated to exhibit immunomodulatory, anti-inflammatory, antihyperglycaemic, antiulcer, antimalarial, antifungal, antibacterial, antiviral, antioxidant, antimutagenic and anticarcinogenic properties. This review summarises the wide range of pharmacological activities of neem leaf.

  8. Adolescent home-leaving and the transition to adulthood

    PubMed Central

    Egondi, Thaddaeus; Kabiru, Caroline; Beguy, Donatien; Kanyiva, Muindi; Jessor, Richard

    2013-01-01

    Home-leaving is considered an important marker of the transition to adulthood and is usually framed as an individual decision. We move beyond this limited assumption to examine a broader conceptualization that might better illuminate home-leaving among youth in impoverished circumstances. We adopt the Problem Behavior Theory-framework to investigate the association of home-leaving with behavioral and psychosocial variables and with other transitions. We use data on adolescents aged 14–22 years from a three-wave study conducted between 2007 and 2010. We used variable- and person-centered cross-sectional analyses, as well as predictive analysis of home-leaving by subsequent waves. Parental controls protection predicted home-leaving by subsequent waves. Overall, protective factors moderated the association of problem behavior involvement with leaving home in Nairobi’s slums. PMID:24089582

  9. 78 FR 8833 - The Family and Medical Leave Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ...This Final Rule amends certain regulations of the Family and Medical Leave Act of 1993 (the FMLA or the Act) to implement amendments to the military leave provisions of the Act made by the National Defense Authorization Act for Fiscal Year 2010, which extends the availability of FMLA leave to family members of members of the Regular Armed Forces for qualifying exigencies arising out of the......

  10. 5 CFR 630.605 - Computation of home leave.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 1 0 0 2 2 1 0 3 3 2 1 4 5 3 1 5 6 4 2 6 7 5 2 7 8 5 2 8 10 6 3 9 11 7 3 10 12 8 4 11 13 9 4 12 15... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Computation of home leave. 630.605... AND LEAVE Home Leave § 630.605 Computation of home leave. (a) For each month of service abroad,...

  11. 5 CFR 630.605 - Computation of home leave.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 1 0 0 2 2 1 0 3 3 2 1 4 5 3 1 5 6 4 2 6 7 5 2 7 8 5 2 8 10 6 3 9 11 7 3 10 12 8 4 11 13 9 4 12 15... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Computation of home leave. 630.605... AND LEAVE Home Leave § 630.605 Computation of home leave. (a) For each month of service abroad,...

  12. Oil from Tobacco Leaves: FOLIUM - Installation of Hydrocarbon Accumulating Pathways in Tobacco Leaves

    SciTech Connect

    2012-01-01

    PETRO Project: LBNL is modifying tobacco to enable it to directly produce fuel molecules in its leaves for use as a biofuel. Tobacco is a good crop for biofuels production because it is an outstanding biomass crop, has a long history of cultivation, does not compete with the national food supply, and is highly responsive to genetic manipulation. LBNL will incorporate traits for hydrocarbon biosynthesis from cyanobacteria and algae, and enhance light utilization and carbon uptake in tobacco, improving the efficiency of photosynthesis so more fuel can be produced in the leaves. The tobacco-generated biofuels can be processed for gasoline, jet fuel or diesel alternatives. LBNL is also working to optimize methods for planting, cultivating and harvesting tobacco to increase biomass production several-fold over the level of traditional growing techniques.

  13. Male bumblebees perform learning flights on leaving a flower but not when leaving their nest.

    PubMed

    Robert, Théo; Frasnelli, Elisa; Collett, Thomas S; Hempel de Ibarra, Natalie

    2017-03-01

    Female bees and wasps demonstrate, through their performance of elaborate learning flights, when and where they memorise features of a significant site. An important feature of these flights is that the insects look back to fixate the site that they are leaving. Females, which forage for nectar and pollen and return with it to the nest, execute learning flights on their initial departure from both their nest and newly discovered flowers. To our knowledge, these flights have so far only been studied in females. Here, we describe and analyse putative learning flights observed in male bumblebees Bombus terrestris L. Once male bumblebees are mature, they leave their nest for good and fend for themselves. We show that, unlike female foragers, males always fly directly away from their nest, without looking back, in keeping with their indifference to their natal nest. In contrast, after males have drunk from artificial flowers, their flights on first leaving the flowers resemble the learning flights of females, particularly in their fixation of the flowers. These differences in the occurrence of female and male learning flights seem to match the diverse needs of the two sexes to learn about disparate, ecologically relevant places in their surroundings.

  14. Work-family balance after childbirth: the association between employer-offered leave characteristics and maternity leave duration.

    PubMed

    Guendelman, Sylvia; Goodman, Julia; Kharrazi, Martin; Lahiff, Maureen

    2014-01-01

    Early return to work after childbirth has been increasing among working mothers in the US. We assessed the relationship between access to employer-offered maternity leave (EOML) (both paid and unpaid) and uptake and duration of maternity leave following childbirth in a socio-economically diverse sample of full-time working women. We focus on California, a state that has long provided more generous maternity leave benefits than those offered by federal maternity leave policies through the State Disability Insurance program. The sample included 691 mothers who gave birth in Southern California in 2002-2003. Using weighted logistic regression, we examined the EOML-maternity leave duration relationship, controlling for whether the leave was paid, as well as other occupational, personality and health-related covariates. Compared with mothers who were offered more than 12 weeks of maternity leave, mothers with <6 weeks of EOML and those offered 6-12 weeks had five times higher odds of returning to work within 12 weeks; those offered no leave had six times higher odds of an early return. These relationships were similar after controlling for whether the leave was paid and after controlling for other occupational and health characteristics. Access to and duration of employer-offered maternity leave significantly determine timing of return to work following childbirth, potentially affecting work-family balance. Policy makers should recognize the pivotal role of employers in offering job security during and after maternity leave and consider widening the eligibility criteria of the Family and Medical Leave Act.

  15. Parental leave for residents and pediatric training programs.

    PubMed

    2013-02-01

    The American Academy of Pediatrics (AAP) is committed to the development of rational, equitable, and effective parental leave policies that are sensitive to the needs of pediatric residents, families, and developing infants and that enable parents to spend adequate and good-quality time with their young children. It is important for each residency program to have a policy for parental leave that is written, that is accessible to residents, and that clearly delineates program practices regarding parental leave. At a minimum, a parental leave policy for residents and fellows should conform legally with the Family Medical Leave Act as well as with respective state laws and should meet institutional requirements of the Accreditation Council for Graduate Medical Education for accredited programs. Policies should be well formulated and communicated in a culturally sensitive manner. The AAP advocates for extension of benefits consistent with the Family Medical Leave Act to all residents and interns beginning at the time that pediatric residency training begins. The AAP recommends that regardless of gender, residents who become parents should be guaranteed 6 to 8 weeks, at a minimum, of parental leave with pay after the infant's birth. In addition, in conformance with federal law, the resident should be allowed to extend the leave time when necessary by using paid vacation time or leave without pay. Coparenting, adopting, or fostering of a child should entitle the resident, regardless of gender, to the same amount of paid leave (6-8 weeks) as a person who takes maternity/paternity leave. Flexibility, creativity, and advanced planning are necessary to arrange schedules that optimize resident education and experience, cultivate equity in sharing workloads, and protect pregnant residents from overly strenuous work experiences at critical times of their pregnancies.

  16. [Pregnant women's sick leave is behind the increased sick leave among women of fertile age. A study of pregnant women's sick leave 1978-1997].

    PubMed

    Sydsjö, A; Sydsjö, G

    2001-08-08

    Sick leave rates among pregnant women have been found to vary substantially over time. 8,884 woman delivered at Linköping and Värnamo Women's Clinics in 1978, 1986, 1988, 1992, 1995 and 1997 were studied. Sick leave nearly doubled between 1978 and 1986, and dropped back to the 1978 level in 1997. The somewhat paradoxical findings in our surveys indicate that attitudes, especially as observed in the youngest age groups, together with a sensible adaptation to the prevailing terms of the social security system, may well be the most plausible explanation. Studies on sick leave among women of fertile age should preferably also contain information on the proportion of sick-listed pregnant women, as a small proportion of pregnant women may have a profound impact on sick leave statistics among all insured women of fertile age.

  17. Phytotoxins from the leaves of Ruta graveolens.

    PubMed

    Hale, Amber L; Meepagala, Kumudini M; Oliva, Anna; Aliotta, Giovanni; Duke, Stephen O

    2004-06-02

    Bioassay-guided fractionation of the ethyl acetate extract of Ruta graveolens (common rue) leaves led to the isolation of the furanocoumarins 5-methoxypsoralen (5-MOP), 8-methoxypsoralen (8-MOP), and the quinolone alkaloid graveoline as phytotoxic constituents. Graveoline and 8-MOP substantially inhibited growth of Lactuca sativa (lettuce) seedlings and reduced chlorophyll content at 100 microM; this effect was not due to a direct effect on chlorophyll synthesis. Radical growth of L. sativa was inhibited by 10 microM 8-MOP. Graveoline inhibited growth of Lemna paucicostata (duckweed) at 100 microM. This is the first report of the phytotoxic activity of graveoline. Growth of Agrostis stolonifera (bentgrass) was inhibited by 5-MOP at 30 microM. All three compounds substantially reduced cell division in Allium cepa (onion) at or below 100 microM. None of the compounds caused significant cellular leakage of Cucumis sativus (cucumber) cotyledon disks at 100 microM. All three compounds inhibit plant growth, at least partially through inhibition of cell division.

  18. The energetic characterization of pineapple crown leaves.

    PubMed

    Braga, R M; Queiroga, T S; Calixto, G Q; Almeida, H N; Melo, D M A; Melo, M A F; Freitas, J C O; Curbelo, F D S

    2015-12-01

    Energetic characterization of biomass allows for assessing its energy potential for application in different conversion processes into energy. The objective of this study is to physicochemically characterize pineapple crown leaves (PC) for their application in energy conversion processes. PC was characterized according to ASTM E871-82, E1755-01, and E873-82 for determination of moisture, ash, and volatile matter, respectively; the fixed carbon was calculated by difference. Higher heating value was determined by ASTM E711-87 and ash chemical composition was determined by XRF. The thermogravimetric and FTIR analyses were performed to evaluate the thermal decomposition and identify the main functional groups of biomass. PC has potential for application in thermochemical processes, showing high volatile matter (89.5%), bulk density (420.8 kg/m(3)), and higher heating value (18.9 MJ/kg). The results show its energy potential justifying application of this agricultural waste into energy conversion processes, implementing sustainability in the production, and reducing the environmental liabilities caused by its disposal.

  19. Maltose Biochemistry and Transport in Plant Leaves

    SciTech Connect

    Weber, Andreas P.M.

    2008-04-25

    Transitory starch builds up in photosynthesizing leaves during the day and is then degraded each night. It has recently been shown through mutant analysis and genetically engineered plants that transitory starch is required for maximal rates of photosynthesis, especially in high carbon dioxide atmospheres. Understanding the pathway by which carbon is exported from chloroplasts at night is limited. Previous work has shown that starch conversion to sucrose at night involves maltose export from chloroplasts. This pathway for carbon export from chloroplasts normally does not occur during the day. The regulation of maltose formation, the transporters that allow export of maltose from the chloroplast, and the cytosolic reactions by which maltose is converted to sucrose remain obscure. Genomic and biochemical approaches are proposed here to address maltose metabolism and transport. The research will cover three areas (1) how are hydrolytic and phosphorylytic starch degradation regulated, (2) how is maltose exported from chloroplasts, and (3) how is maltose converted to sucrose in the cytosol? It is expected that this research will lead to new insights about photosynthesis at high carbon dioxide levels, how carbon is partitioned in plants, and how partitioning can be altered to adapt plants to human needs.

  20. Ensilage of cardboard and date palm leaves.

    PubMed

    Baroon, Z; El-Nawawy, A S; Al-Othman, A

    2004-01-01

    Eight treatments of cardboard (CB) and date palm leaves (DPL) with or without alkali treatments plus molasses, dates, and ammonium sulfate were ensiled in laboratory silos. Latobacillus plantarum and Saccharomyces cerevisiae inoculants were added at an application rate of 10(5) cfu/g of silage to study their possible influence on the fermentation process. Silos were sealed and incubated at 30 degrees C. The anaerobic ensiling was evaluated for chemical and microbiological variables by opening the silos after 30, 60, and 90 days. After 90 days, significantly low pH values (5.2-3.5) were obtained. The percentages of hemicellulose, cellulose, lignin, and ash were determined. Concentrations of reducing sugars, ether extract, and crude protein tended to be acceptable among treatments. Silages showed a significantly high lactic acid concentration (up to 4.3%) and only traces of butyric acid (below 1%). Also changes in acetic and propionic acids concentrations were determined. Lactobacillus populations remained almost static while yeast and molds populations tended to be lower after 90 days of ensilage. Neither alkali treatment nor microbial inoculants showed a relationship with the ensiling process. Thus, overall, it was concluded that CB and DPL can be effectively ensiled and the resultant silages are acceptable to merit their use as ruminant feed in arid regions.

  1. 29 CFR 825.207 - Substitution of paid leave.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... employer, will run concurrently with the unpaid FMLA leave. Accordingly, the employee receives pay pursuant... condition may result from injury to the employee “on or off” the job. If the employer designates the leave... (FLSA) permits public employers under prescribed circumstances to substitute compensatory time...

  2. 29 CFR 825.207 - Substitution of paid leave.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... employer, will run concurrently with the unpaid FMLA leave. Accordingly, the employee receives pay pursuant... condition may result from injury to the employee “on or off” the job. If the employer designates the leave... (FLSA) permits public employers under prescribed circumstances to substitute compensatory time...

  3. PHARMACOGNOSY OF LEAVES OF WRIGHTIA TINCTORIA R. BR.

    PubMed Central

    Mahadevan, N.; Moorthy, K.; Perumal, P.; Raju, S. Varadha

    1998-01-01

    Wrightia tinctora is a tree widely used by the peoples of Tamil Nadu as a traditional medicine for pain and inflammations. Latex form the plant especially from leaves is directly applied on inflammation. This plant is very closely related to other species of Wrightia and hence pharmacognostical and preliminary phytochemical studies of Wrightia tinctoria leaves were carried out. PMID:22556873

  4. Leaves as composites of latent developmental and evolutionary shapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Across plants, leaves exhibit profound diversity in shape. As a single leaf expands, its shape is in constant flux. Additionally, plants may also produce leaves with different shapes at successive nodes. Because leaf shape can vary in many different ways, theoretically the effects of distinct proces...

  5. Why Do New Teachers Leave? How Could They Stay?

    ERIC Educational Resources Information Center

    Simos, Elaine

    2013-01-01

    The author of this article posits that some teachers leave the profession because they entered it with unrealistic expectations, and that the reality of multiple preparations, unpaid orientation sessions, and large student loads is overburdening.for new teachers. Many new teachers leave their positions because of the dissonance between their…

  6. Postharvest quarantine treatments for Diaphorina citri on infested curry leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies were conducted to evaluate treatments that reduce survival and attachment of Diaphorina citri nymphs on infested curry leaves (Bergera koenigii). Decontamination of curry leaves infested with D. citri in relation to disinfectant (none or Pro-San), temperature (0, 40, and 50°C), and treatment...

  7. 38 CFR 21.8340 - Leaves of absence.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) VOCATIONAL REHABILITATION AND EDUCATION Vocational Training and Rehabilitation for Certain Children of...: 38 U.S.C. 1804(c), 1814) (b) Basis for leave of absence. The VR&E case manager may grant the child... prolonged periods of absence, the VR&E case manager may approve leaves of absence only if the case...

  8. 29 CFR 825.120 - Leave for pregnancy or birth.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... pregnancy or birth. (a) General rules. Eligible employees are entitled to FMLA leave for pregnancy or birth... condition. Note, too, that many State pregnancy disability laws specify a period of disability either...

  9. 29 CFR 825.120 - Leave for pregnancy or birth.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... pregnancy or birth. (a) General rules. Eligible employees are entitled to FMLA leave for pregnancy or birth..., that many State pregnancy disability laws specify a period of disability either before or after...

  10. 29 CFR 825.120 - Leave for pregnancy or birth.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... pregnancy or birth. (a) General rules. Eligible employees are entitled to FMLA leave for pregnancy or birth..., that many State pregnancy disability laws specify a period of disability either before or after...

  11. 29 CFR 825.120 - Leave for pregnancy or birth.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... pregnancy or birth. (a) General rules. Eligible employees are entitled to FMLA leave for pregnancy or birth... condition. Note, too, that many State pregnancy disability laws specify a period of disability either...

  12. 29 CFR 825.120 - Leave for pregnancy or birth.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... pregnancy or birth. (a) General rules. Eligible employees are entitled to FMLA leave for pregnancy or birth... condition. Note, too, that many State pregnancy disability laws specify a period of disability either...

  13. The Meaning of Korean Women's Career-Leaving Experience

    ERIC Educational Resources Information Center

    Lee, Yu-Jin

    2010-01-01

    What is the meaning of Korean women's career-leaving experience? To answer this question, this study adopted a hermeneutic phenomenology approach. My intention was to search for the deeper meaning of Korean women's career-leaving experience from their perspective. Ten Korean women who had left their careers due to their domestic roles in their…

  14. 5 CFR 630.909 - Use of transferred annual leave.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... purpose of a medical emergency for which the leave recipient was approved. (b) Except as provided in § 630.907, during each biweekly pay period that a leave recipient is affected by a medical emergency, he or... and requirements imposed by chapter 63 of title 5, United States Code, part 630 of this chapter,...

  15. Early Effects of the San Francisco Paid Sick Leave Policy

    PubMed Central

    Colla, Carrie H.; Dow, William H.; Dube, Arindrajit; Lovell, Vicky

    2014-01-01

    Objectives. We examined employers’ responses to San Francisco, California’s 2007 Paid Sick Leave Ordinance. Methods. We used the 2009 Bay Area Employer Health Benefits Survey to describe sick leave policy changes and the policy’s effects on firm (n = 699) operations. Results. The proportion of firms offering paid sick leave in San Francisco grew from 73% in 2006 to 91% in 2009, with large firms (99%) more likely to offer sick leave than are small firms (86%) in 2009. Most firms (57%) did not make any changes to their sick leave policy, although 17% made a major change to sick leave policy to comply with the law. Firms beginning to offer sick leave reported reductions in other benefits (39%), worse profitability (32%), and increases in prices (18%) but better employee morale (17%) and high support for the policy (71%). Many employers (58%) reported some difficulty understanding legal requirements, complying administratively, or reassigning work responsibilities. Conclusions. There was a substantial increase in paid sick leave coverage after the mandate. Employers reported some difficulties in complying with the law but supported the policy overall. PMID:24432927

  16. 29 CFR 825.301 - Designation of FMLA leave.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... employment, reinstatement, promotion, or any other relief tailored to the harm suffered. See § 825.400(c... designate the leave properly, but the employee's own serious health condition prevented him or her from... leave to provide care for a son or daughter with a serious health condition believing it would not...

  17. 29 CFR 825.301 - Designation of FMLA leave.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... employment, reinstatement, promotion, or any other relief tailored to the harm suffered (see § 825.400(c... designate the leave properly, but the employee's own serious health condition prevented him or her from... leave to provide care for a son or daughter with a serious health condition believing it would not...

  18. Towards a More Telling Way of Understanding Early School Leaving

    ERIC Educational Resources Information Center

    Hodgson, David

    2007-01-01

    This paper is concerned with research into early school leaving. A narrative interview approach was used to document and analyse the experiences, processes and decisions that a small sample of boys made prior to leaving school, in this case, before completing year 10 and 11. Data collected in 2004 indicate that schools along with students…

  19. Organizational Justice and Social Workers' Intentions to Leave Agency Positions

    ERIC Educational Resources Information Center

    Kim, Tae Kuen; Solomon, Phyllis; Jang, Cinjae

    2012-01-01

    The authors investigated the impact of organizational justice on social workers' intention to leave Korean social service agencies. Specifically, this study concentrated on the moderating effect of organizational justice on the relationship between burnout and intention to leave. The authors surveyed 218 front-line social workers from 51 social…

  20. Chicoric Acid Found in Basil (Ocimum basilicum L.) Leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is the first report to identify the presence of chicoric acid (cichoric acid; also known as dicaffeoyltartaric acid) in basil leaves. Rosmarinic acid, chicoric acid, and caftaric acid (in the order of most abundant to least; all derivatives of caffeic acid) were identified in fresh basil leaves...

  1. 48 CFR 752.7031 - Leave and holidays.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... requirements of the project precluded the employee from taking such leave, and the Contracting Officer (with... for home leave will be limited to the time required for travel by the most expeditious air route. The... control as determined by the Contracting Officer, does not return overseas and complete the...

  2. Leaving the Parental Home: Patterns in Six Latin American Countries.

    ERIC Educational Resources Information Center

    De Vos, Susan

    1989-01-01

    Used mid-1970s World Fertility Survey cross-sectional data to analyze sociodemographic determinants of home-leaving by young Latin American adults (N=68,534). Found marriage as major reason for home-leaving and sex, urban/rural residence, education, and work as other important determinants. Noted international differences. (Author/CM))

  3. Predicting Turnover: Validating the Intent to Leave Child Welfare Scale

    ERIC Educational Resources Information Center

    Auerbach, Charles; Schudrich, Wendy Zeitlin; Lawrence, Catherine K.; Claiborne, Nancy; McGowan, Brenda G.

    2014-01-01

    A number of proxies have been used in child welfare workforce research to represent actual turnover; however, there have been no psychometric studies to validate a scale specifically designed for this purpose. The Intent to Leave Child Welfare Scale is a proxy for actual turnover that measures workers' intention to leave. This scale was validated…

  4. Reasons that Orthodontic Faculty Teach and Consider Leaving Teaching.

    ERIC Educational Resources Information Center

    Kula, Katherine; Glaros, Alan; Larson, Brent; Tuncay, Orhan

    2000-01-01

    Surveyed full-time (FT) and part-time (PT) orthodontic faculty about reasons for considering leaving academia. About 38 percent FT and 25 percent PT were currently considering leaving. The factors most important for FT were work-related: salary support, financial support of department, and control over work or destiny. For PTs, the reasons were:…

  5. Early iron deficiency stress response in leaves of sugar beet.

    PubMed Central

    Winder, T L; Nishio, J N

    1995-01-01

    Iron nutrient deficiency was investigated in leaves of hydroponically grown sugar beets (Beta vulgaris) to determine how ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) gene expression is affected when thylakoid components of photosynthesis are diminished. Rubisco polypeptide content was reduced by 60% in severely iron-stressed leaves, and the reduction was directly correlated to chlorophyll content. The concentration of Rubisco protein in iron-stressed leaves was found to be regulated by availability of mRNAs, and CO2 fixation by Rubisco was reduced from 45 mumol CO2 m-2 s-1 in extracts from iron-sufficient leaves to 20 mumol CO2 m-2 s-1 in extracts from severely stressed leaves. The rate of CO2 fixation was directly correlated to leaf chlorophyll content. Rubisco in iron-sufficient control leaves was 59% activated, whereas in severely stressed leaves grown under the same light, Rubisco was 43% activated. RNA synthesis was reduced by about 50% in iron-deficient leaves, but 16S and 25S rRNA and ctDNA were essentially unaffected by iron stress. PMID:7659749

  6. Carbon monoxide photoproduction from rice and maize leaves

    NASA Astrophysics Data System (ADS)

    Yonemura, S.; Morokuma, M.; Kawashima, S.; Tsuruta, H.

    We investigated CO photoproduction from intact leaves of rice ( Oryza sativa L.) and maize ( Zea mays L.) by laboratory experiments. CO photoproduction showed positive correlation with light intensity and was positively dependent on oxygen concentration. The average CO photoproduction was 2.6±0.3×10 10 molecules cm -2 s -1 from rice leaves and 2.2±0.1×10 10 molecules cm -2 s -1 from maize leaves ( n=5) at a radiation intensity of 49 mW cm -2. CO photoproduction from senescent rice leaves was 9 times greater (25.7±1.5×10 10 molecules cm -2 s -1, n=2) at the same radiation intensity than from live leaves, and responded slowly to changes in oxygen concentration and light intensity. CO photoproduction showed no correlation with CO 2 concentration or humidity. This indicates that CO photoproduction in leaves is not directly controlled by carbon metabolism or stomatal conductance. The lack of dependence on stomatal conductance leads to the conclusion that the diffusion of CO from inside the leaves to the atmosphere is not a controlling factor for CO photoproduction from rice and maize leaves.

  7. Early School-Leaving in Spain: Evolution, Intensity and Determinants

    ERIC Educational Resources Information Center

    Fernandez-Macias, Enrique; Anton, Jose-Ignacio; Brana, Francisco-Javier; De Bustillo, Rafael Munoz

    2013-01-01

    Spain has one of the highest levels of early school leaving and educational failure of the European Union. The purpose of this paper is to analyse the anatomy of early school leaving in Spain and its characteristics. In order to do so, in the first part we discuss the measurement problems related with this concept and the evolution of drop-out…

  8. 77 FR 22519 - The Family and Medical Leave Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-16

    ... Hour Division 29 CFR Part 825 RIN 1215-AB76 and RIN 1235-AA03 The Family and Medical Leave Act AGENCY... certain regulations of the Family and Medical Leave Act of 1993 (FMLA). On February 15, 2012, the... for Comment The Notice of Proposed Rulemaking (NPRM) proposes revisions to the Family and Medical...

  9. Carbon balance in leaves of young poplar trees.

    PubMed

    Mayrhofer, S; Heizmann, U; Magel, E; Eiblmeier, M; Müller, A; Rennenberg, H; Hampp, R; Schnitzler, J-P; Kreuzwieser, J

    2004-11-01

    In the present study, important components of carbon metabolism of mature leaves of young poplar trees (Populus x canescens) were determined. Carbohydrate concentrations in leaves and xylem sap were quantified at five different times during the day and compared with photosynthetic gas exchange measurements (net assimilation, transpiration and rates of isoprene emission). Continuously measured xylem sap flow rates, with a time resolution of 15 min, were used to calculate diurnal balances of carbon metabolism of whole mature poplar leaves on different days. Loss of photosynthetically fixed carbon by isoprene emission and dark respiration amounted to 1% and 20%. The most abundant soluble carbohydrates in leaves and xylem sap were glucose, fructose and sucrose, with amounts of approx. 2 to 12 mmol m(-2) leaf area in leaves and about 0.2 to 15 mM in xylem sap. Clear diurnal patterns of carbohydrate concentration in xylem sap and leaves, however, were not observed. Calculations of the carbon transport rates in the xylem to the leaves were based on carbohydrate concentrations in xylem sap and xylem sap flow rates. This carbon delivery amounted to about 3 micromol C m(-2) s(-1) during the day and approx. 1 micromol C m(-2) s(-1) at night. The data demonstrated that between 9 and 28 % of total carbon delivered to poplar leaves during 24 h resulted from xylem transport and, hence, provide a strong indication for a significant rate of carbon cycling within young trees.

  10. Phenolic composition and antioxidant activity of Malus domestica leaves.

    PubMed

    Liaudanskas, Mindaugas; Viškelis, Pranas; Raudonis, Raimondas; Kviklys, Darius; Uselis, Norbertas; Janulis, Valdimaras

    2014-01-01

    The aim of this study was to determine the composition and content of phenolic compounds in the ethanol extracts of apple leaves and to evaluate the antioxidant activity of these extracts. The total phenolic content was determined spectrophotometrically, as well as the total flavonoid content in the ethanol extracts of apple leaves and the antioxidant activity of these extracts, by the ABTS, DPPH, and FRAP assays. The highest amount of phenolic compounds and flavonoids as well as the highest antioxidant activity was determined in the ethanol extracts obtained from the apple leaves of the cv. Aldas. The analysis by the HPLC method revealed that phloridzin was a predominant component in the ethanol extracts of the apple leaves of all cultivars investigated. The following quercetin glycosides were identified and quantified in the ethanol extracts of apple leaves: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Quercitrin was the major compound among quercetin glycosides.

  11. Composition of epiphytic bacterial communities differs on petals and leaves.

    PubMed

    Junker, R R; Loewel, C; Gross, R; Dötterl, S; Keller, A; Blüthgen, N

    2011-11-01

    The epiphytic bacterial communities colonising roots and leaves have been described for many plant species. In contrast, microbiologists have rarely considered flowers of naturally growing plants. We identified bacteria isolated from the surface of petals and leaves of two plant species, Saponaria officinalis (Caryophyllaceae) and Lotus corniculatus (Fabaceae). The bacterial diversity was much lower on petals than on leaves of the same plants. Moreover, the bacterial communities differed strongly in composition: while Pseudomonadaceae and Microbacteriaceae were the most abundant families on leaves, Enterobacteriaceae dominated the floral communities. We hypothesise that antibacterial floral volatiles trigger the low diversity on petals, which is supported by agar diffusion assays using substances emitted by flowers and leaves of S. officinalis. These results suggest that bacteria should be included in the interpretation of floral traits, and possible effects of bacteria on pollination are proposed and discussed.

  12. The health effects of leaving school in a bad economy.

    PubMed

    Maclean, Johanna Catherine

    2013-09-01

    This study investigates the lasting health effects of leaving school in a bad economy. Three empirical patterns motivate this study: Leaving school in a bad economy has persistent and negative career effects, career and health outcomes are correlated, and fluctuations in contemporaneous economic conditions affect health in the short-run. I draw data from the National Longitudinal Survey of Youth 1979 Age 40 Health Supplement. Members of my sample left school between 1976 and 1992. I find that men who left school when the school-leaving state unemployment rate was high have worse health at age 40 than otherwise similar men, while leaving school in a bad economy lowers depressive symptoms at age 40 among women. A 1 percentage point increase in the school-leaving state unemployment rate leads to a 0.5% to 18% reduction in the measured health outcomes among men and a 6% improvement in depressive symptoms among women.

  13. Phenolic Composition and Antioxidant Activity of Malus domestica Leaves

    PubMed Central

    Viškelis, Pranas; Uselis, Norbertas

    2014-01-01

    The aim of this study was to determine the composition and content of phenolic compounds in the ethanol extracts of apple leaves and to evaluate the antioxidant activity of these extracts. The total phenolic content was determined spectrophotometrically, as well as the total flavonoid content in the ethanol extracts of apple leaves and the antioxidant activity of these extracts, by the ABTS, DPPH, and FRAP assays. The highest amount of phenolic compounds and flavonoids as well as the highest antioxidant activity was determined in the ethanol extracts obtained from the apple leaves of the cv. Aldas. The analysis by the HPLC method revealed that phloridzin was a predominant component in the ethanol extracts of the apple leaves of all cultivars investigated. The following quercetin glycosides were identified and quantified in the ethanol extracts of apple leaves: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Quercitrin was the major compound among quercetin glycosides. PMID:25302319

  14. The phenotype of grape leaves caused by acetochlor or fluoroglycofen, and effects of latter herbicide on grape leaves.

    PubMed

    Tan, Wei; Liang, Ting; Li, Qingliang; Du, Yuanpeng; Zhai, Heng

    2014-09-01

    Fluoroglycofen and acetochlor are two different herbicides used in vineyards to eradicate weeds. This present study first characterized the effects of these chemicals on phenotype of grape leaves. Results showed that acetochlor caused the middle- and upper-node grape leaves become yellow at 60th day after treatment, while fluoroglycofen caused the ones became dark green. Then the effects of fluoroglycofen on photosynthetic pigments and chloroplast ultrastructure were characterized. Results showed that fluoroglycofen increased the chlorophyll and carotenoid contents by different extent in different node leaves, while it did not affect the net photosynthesis rate significantly. Chloroplast ultrastructure analysis showed that the gap between thylakoids layers in few chloroplasts of middle-node leaves increased, which was also observed in ones of upper-node leaves; the number and size of chloroplast increased. Analysis on the deformed leaves of grapevines treated with 375 g ai ha(-1) fluoroglycofen showed that the starch grain per cell was much more and larger than that in the same size control leaves; the dark green and yellow parts had more or fewer chloroplast than the control, respectively, but both with more grana per chloroplast and less layers per granum. Chloroplasts went larger and round. Taken together, these results suggested that fluoroglycofen caused the grape leaves become dark green, which might be associated with the changes of chloroplast; the growth inhibition in the second year might be due to accumulation of starch.

  15. Paid Educational Leave and Self-Directed Learning: Implications for Legislation on the Learning Leave Scheme in South Korea

    ERIC Educational Resources Information Center

    Oh, Jeong Rok; Park, Cho Hyun; Jo, Sung Jun

    2016-01-01

    Purpose: The purposes of this study are to explore paid educational leave (PEL), self-directed learning (SDL) and the relationship between them; and to identify the implications for legislation on the learning leave scheme in South Korea. Design/Methodology/Approach: The research method of the study is a literature review. Articles were identified…

  16. Review of Leaving it at the office.

    PubMed

    Hays, Kate F

    2008-06-01

    Reviews the book, Leaving it at the office by John C. Norcross and James D. Guy (2007). This book is filled with compassionate fervor and recognition of the satisfactions of our professional lives. Twelve central elements to therapist self-care form the base for the 12 chapters of the book. Describing themselves as "integrative psychotherapists," Norcross and Guy begin from the perspective of seeing the person of the psychotherapist as a valued human being. They encourage us to refocus on the rewards of our profession, while recognizing its hazards. Body, mind, and soul or spirit are each given their due: attending to activity, awareness and restructuring of our own cognitions (regardless of theoretical perspective), engaging in personal therapy of one kind or another, and cultivating spirituality or mission, creativity and growth. Each chapter sets out information that is described as a field guide rather than an instructional manual, a "curious mix of 'how to,' 'you should,' and 'chill-out.'" Information is culled from many types of sources: the authors' own research and that of a wide variety of others' with respect to self-care; workshops that the authors have offered regarding self-care; and clinical wisdom derived in part from interviews with master clinicians. Chapters are structured into sections focused on self-care both at the office and away from the office. (Yes, sometimes our not-great self-care extends outside of the office setting.) A summary self-care list ends each chapter, one that could serve as a wellness reminder or checklist for any individual. Further, the authors offer specific recommended reading at the end of each chapter, as well as an extensive full reference section at the end of the book. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  17. Maltose Biochemistry and Transport in Plant Leaves

    SciTech Connect

    Sharkey, Thomas D

    2012-05-03

    Starch is a desirable plant product for both food and biofuel. Leaf starch is ideal for use in biofuels because it does not compete with grain starch, which is used for food. Starch is accumulated in plant leaves during the day and broken down at night. If we can manipulate leaf starch breakdown it may be possible to design a plant that provides both grain starch for food and leaf starch for biofuel. The pathway of leaf starch breakdown was not known when this work started. Preliminary evidence had shown that maltose was the primary product of leaf starch breakdown (Weise, Weber & Sharkey, 2004) and that it was metabolized by a disproportionating enzyme called amylomaltase but given the initials DPE2 (Lu & Sharkey, 2004). In this work we showed that only one form of maltose was metabolically active (Weise et al., 2005a) and that maltose was located in two different places when the amylomaltase was knocked out but only inside the chloroplast when the maltose transporter was knocked out (Lu et al., 2006a). This allowed us to estimate the energetics of maltose export and to show that maltose export is more efficient than glucose export (Weise et al., 2005b). We examined how daylength affected starch breakdown rate and found that starch breakdown rate could respond to changes in daylength within one day (Lu, Gehan & Sharkey, 2005). We also were able to show a second starch breakdown pathway by chloroplastic starch phosphorylase (Weise et al., 2006). Work to this point was summarized in a review (Lu & Sharkey, 2006). We were able to show that the amylomaltase in plants could substitute for the amylomaltase in bacteria (Lu et al., 2006b). In this paper we also showed the importance of a second enzyme called alpha-glucan phosphorylase in starch breakdown. Finally, we were able to determine the enzymatic mechanism of the amylomaltase (Steichen, Petty & Sharkey, 2008). These results have laid the groundwork for manipulating plants for improved biofuel production.

  18. Isoprene Emission from Aspen Leaves 1

    PubMed Central

    Monson, Russell K.; Fall, Ray

    1989-01-01

    Isoprene emission rates from quaking aspen (Populus tremuloides Michx.) leaves were measured simultaneously with photosynthesis rate, stomatal conductance, and intercellular CO2 partial pressure. Isoprene emission required the presence of CO2 or O2, but not both. The light response of isoprene emission rate paralleled that of photosynthesis. Isoprene emission was inhibited by decreasing ambient O2 from 21% to 2%, only when there was oxygen insensitive photosynthesis. Mannose (10 millimolar) fed through cut stems resulted in strong inhibition of isoprene emission rate and is interpreted as evidence that isoprene biosynthesis requires either the export of triose phosphates from the chloroplast, or the continued synthesis of ATP. Light response experiments suggest that photosynthetically generated reductant or ATP is required for isoprene biosynthesis. Isoprene biosynthesis and emission are not directly linked to glycolate production through photorespiration, contrary to previous reports. Isoprene emission rate was inhibited by above-ambient CO2 partial pressures (640 microbar outside and 425 microbar inside the leaf). The inhibition was not due to stomatal closure. This was established by varying ambient humidity at normal and elevated CO2 partial pressures to measure isoprene emission rates over a range of stomatal conductances. Isoprene emission rates were inhibited at elevated CO2 despite no change in stomatal conductance. Addition of abscisic acid to the transpiration stream dramatically inhibited stomatal conductance and photosynthesis rate, with a slight increase in isoprene emission rate. Thus, isoprene emission is independent of stomatal conductance, and may occur through the cuticle. Temperature had an influence on isoprene emission rate, with the Q10 being 1.8 to 2.4 between 35 and 45°C. At these high temperatures the amount of carbon lost through isoprene emission was between 2.5 and 8% of that assimilated through photosynthesis. This represents a

  19. Maltose Biochemistry and Transport in Plant Leaves

    SciTech Connect

    Thomas D. Sharkey

    2010-01-28

    Final Technical Report for DOE grant DE-FG02-04ER15565 Maltose Biochemistry and Transport in Plant Leaves PI Thomas D. Sharkey University of Wisconsin-Madison Starch is a desirable plant product for both food and biofuel. Leaf starch is ideal for use in biofuels because it does not compete with grain starch, which is used for food. Starch is accumulated in plant leaves during the day and broken down at night. If we can manipulate leaf starch breakdown it may be possible to design a plant that provides both grain starch for food and leaf starch for biofuel. The pathway of leaf starch breakdown was not known when this work started. Preliminary evidence had shown that maltose was the primary product of leaf starch breakdown (Weise, Weber & Sharkey, 2004) and that it was metabolized by a disproportionating enzyme called amylomaltase but given the initials DPE2 (Lu & Sharkey, 2004). In this work we showed that only one form of maltose was metabolically active (Weise et al., 2005a) and that maltose was located in two different places when the amylomaltase was knocked out but only inside the chloroplast when the maltose transporter was knocked out (Lu et al., 2006a). This allowed us to estimate the energetics of maltose export and to show that maltose export is more efficient than glucose export (Weise et al., 2005b). We examined how daylength affected starch breakdown rate and found that starch breakdown rate could respond to changes in daylength within one day (Lu, Gehan & Sharkey, 2005). We also were able to show a second starch breakdown pathway by chloroplastic starch phosphorylase (Weise et al., 2006). Work to this point was summarized in a review (Lu & Sharkey, 2006). We were able to show that the amylomaltase in plants could substitute for the amylomaltase in bacteria (Lu et al., 2006b). In this paper we also showed the importance of a second enzyme called alpha-glucan phosphorylase in starch breakdown. Finally, we were able to determine the enzymatic mechanism of

  20. Green synthesis of gold nanoparticles using extracts of Artocarpus Lakoocha fruit and its leaves, and Eriobotrya Japonica leaves

    NASA Astrophysics Data System (ADS)

    Sharma, Ankita; Dhiman, Naresh; Singh, Bhanu P.; Gathania, Arvind K.

    2014-04-01

    Gold nanoparticles (AuNPs) synthesis is demonstrated successfully using fresh young leaves of Artocarpus Lakoocha (A. Lakoocha), fruit pulp of A. Lakoocha and loquat (Eriobotrya Japonica) leaves. We have also compared green synthesis with chemical assisted tri-n-octyl-phosphine (TOP) stabilized gold nanoparticles. Samples were characterized with transmission electron microscopy (TEM), Fourier transform infrared spectroscopy and UV-Visible spectroscopy. TEM images have shown that the average size of the particles is 15.06, 36.8 and 25.08 nm for A. Lakoocha fruits, A. Lakoocha leaves and loquat leaves assisted gold nanoparticles, respectively. Hydrogen tetrachloroaurate is reduced and AuNPs are stabilized by phenols, hydroxyls and carboxyls groups such as terpenoids, flavonoids, tannins etc, present in young leaves and fruit extracts. It was observed that green synthesis using botanical extracts is a cost effective and non- toxic way for nanoparticle preparation.

  1. Phloem unloading in developing leaves of sugar beet

    SciTech Connect

    Schmalstig, J.G.

    1985-01-01

    Physiological and transport data support a symplastic pathway for phloem unloading in developing leaves of sugar beet (Beta vulgaris L. Klein E, multigerm). The sulfhydryl inhibitor parachloromercuribenzene sulfonic acid (PCMBS) inhibited uptake of (/sup 14/C)-sucrose added to the free space of developing leaves, but did not affect import of (/sup 14/C)-sucrose during steady-state /sup 14/CO/sub 2/ labeling of a source leaf. The passively-transported xenobiotic sugar, (/sup 14/C)-L-glucose did not readily enter mesophyll cells when supplied through the cut end of the petiole of a sink leaf as determined by whole leaf autoradiography. In contrast, (/sup 14/C)-L-glucose translocated through the phloem from a mature leaf, rapidly entered mesophyll cells, and was evenly distributed between mesophyll and veins. Autoradiographs of developing leaves following a pulse of /sup 14/CO/sub 2/ to a source leaf revealed rapid passage of phloem translocated into progressively higher order veins as the leaf developed. Entry into V order veins occurred during the last stage of import through the phloem. Import into developing leaves was inhibited by glyphosate (N-phosphomethylglycine), a herbicide which inhibits the aromatic amino acid pathway and hence protein synthesis. Glyphosate also stopped net starch accumulation in sprayed mature leaves, but did not affect export of carbon from treated leaves during the time period that import into developed leaves was inhibited.

  2. Ingress of Salmonella enterica Typhimurium into tomato leaves through hydathodes.

    PubMed

    Gu, Ganyu; Cevallos-Cevallos, Juan M; van Bruggen, Ariena H C

    2013-01-01

    Internal contamination of Salmonella in plants is attracting increasing attention for food safety reasons. In this study, three different tomato cultivars "Florida Lanai", "Crown Jewel", "Ailsa Craig" and the transgenic line Sp5 of "Ailsa Craig" were inoculated with 1 µl GFP-labeled Salmonella Typhimurium through guttation droplets at concentrations of 10(9) or 10(7) CFU/ml. Survival of Salmonella on/in tomato leaves was detected by both direct plating and enrichment methods. Salmonella cells survived best on/in the inoculated leaves of cultivar "Ailsa Craig" and decreased fastest on/in "Florida Lanai" leaves. Increased guttation in the abscisic acid over-expressing Sp5 plants may have facilitated the entrance of Salmonella into leaves and the colonization on the surface of tomato leaves. Internalization of Salmonella Typhimurium in tomato leaves through guttation drop inoculation was confirmed by confocal laser microscopy. For the first time, convincing evidence is presented that S. enterica can enter tomato leaves through hydathodes and move into the vascular system, which may result in the internal translocation of the bacteria inside plants.

  3. Abscisic Acid Biosynthesis in Leaves and Roots of Xanthium strumarium.

    PubMed

    Creelman, R A; Gage, D A; Stults, J T; Zeevaart, J A

    1987-11-01

    RESEARCH ON THE BIOSYNTHESIS OF ABSCISIC ACID (ABA) HAS FOCUSED PRIMARILY ON TWO PATHWAYS: (a) the direct pathway from farnesyl pyrophosphate, and (b) the indirect pathway involving a carotenoid precursor. We have investigated which biosynthetic pathway is operating in turgid and stressed Xanthium leaves, and in stressed Xanthium roots using long-term incubations in (18)O(2). It was found that in stressed leaves three atoms of (18)O from (18)O(2) are incorporated into the ABA molecule, and that the amount of (18)O incorporated increases with time. One (18)O atom is incorporated rapidly into the carboxyl group of ABA, whereas the other two atoms are very slowly incorporated into the ring oxygens. The fourth oxygen atom in the carboxyl group of ABA is derived from water. ABA from stressed roots of Xanthium incubated in (18)O(2) shows a labeling pattern similar to that of ABA in stressed leaves, but with incorporation of more (18)O into the tertiary hydroxyl group at C-1' after 6 and 12 hours than found in ABA from stressed leaves. It is proposed that the precursors to stress-induced ABA are xanthophylls, and that a xanthophyll lacking an oxygen function at C-6 (carotenoid numbering scheme) plays a crucial role in ABA biosynthesis in Xanthium roots. In turgid Xanthium leaves, (18)O is incorporated into ABA to a much lesser extent than it is in stressed leaves, whereas exogenously applied (14)C-ABA is completely catabolized within 48 hours. This suggests that ABA in turgid leaves is either (a) made via a biosynthetic pathway which is different from the one in stressed leaves, or (b) has a half-life on the order of days as compared with a half-life of 15.5 hours in water-stressed Xanthium leaves. Phaseic acid showed a labeling pattern similar to that of ABA, but with an additional (18)O incorporated during 8'-hydroxylation of ABA to phaseic acid.

  4. 29 CFR 825.100 - The Family and Medical Leave Act.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false The Family and Medical Leave Act. 825.100 Section 825.100... THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Coverage Under the Family and Medical Leave Act § 825.100 The Family and Medical Leave Act. (a) The Family and Medical Leave Act of 1993, as amended, (FMLA or...

  5. 5 CFR 630.908 - Limitations on donation of annual leave.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Limitations on donation of annual leave... REGULATIONS ABSENCE AND LEAVE Voluntary Leave Transfer Program § 630.908 Limitations on donation of annual... amount of annual leave he or she would be entitled to accrue during the leave year in which the...

  6. 29 CFR 825.100 - The Family and Medical Leave Act.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false The Family and Medical Leave Act. 825.100 Section 825.100... THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Coverage Under the Family and Medical Leave Act § 825.100 The Family and Medical Leave Act. (a) The Family and Medical Leave Act of 1993, as amended, (FMLA or...

  7. 29 CFR 825.100 - The Family and Medical Leave Act.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false The Family and Medical Leave Act. 825.100 Section 825.100... THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Coverage Under the Family and Medical Leave Act § 825.100 The Family and Medical Leave Act. (a) The Family and Medical Leave Act of 1993, as amended, (FMLA or...

  8. Phytotoxic steroidal saponins from Agave offoyana leaves.

    PubMed

    Pérez, Andy J; Simonet, Ana M; Calle, Juan M; Pecio, Łukasz; Guerra, José O; Stochmal, Anna; Macías, Francisco A

    2014-09-01

    A bioassay-guided fractionation of Agave offoyana leaves led to the isolation of five steroidal saponins (1-5) along with six known saponins (6-11). The compounds were identified as (25R)-spirost-5-en-2α,3β-diol-12-one 3-O-{α-l-rhamnopyranosyl-(1→3)-O-β-d-glucopyranosyl-(1→2)-O-[β-d-xylopyranosyl-(1→3)]-O-β-d-glucopyranosyl-(1→4)-O-β-d-galactopyranoside} (1), (25R)-spirost-5-en-3β-ol-12-one 3-O-{α-l-rhamnopyranosyl-(1→3)-O-β-d-glucopyranosyl-(1→2)-O-[β-d-xylopyranosyl-(1→3)]-O-β-d-glucopyranosyl-(1→4)-O-β-d-galactopyranoside} (2), (25R)-spirost-5-en-3β-ol-12-one 3-O-{β-d-xylopyranosyl-(1→3)-O-β-d-glucopyranosyl-(1→2)-O-[β-d-xylopyranosyl-(1→3)]-O-β-d-glucopyranosyl-(1→4)-O-β-d-galactopyranoside} (3), (25R)-26-O-β-d-glucopyranosylfurost-5-en-3β,22α,26-triol-12-one 3-O-{α-l-rhamnopyranosyl-(1→3)-O-β-d-glucopyranosyl-(1→2)-O-[β-d-xylopyranosyl-(1→3)]-O-β-d-glucopyranosyl-(1→4)-O-β-d-galactopyranoside} (4) and (25R)-26-O-β-d-glucopyranosylfurost-5-en-3β,22α,26-triol-12-one 3-O-{β-d-xylopyranosyl-(1→3)-O-β-d-glucopyranosyl-(1→2)-O-[β-d-xylopyranosyl-(1→3)]-O-β-d-glucopyranosyl-(1→4)-O-β-d-galactopyranoside} (5) by comprehensive spectroscopic analysis, including one- and two-dimensional NMR techniques, mass spectrometry and chemical methods. The phytotoxicity of the isolated compounds on the standard target species Lactuca sativa was evaluated.

  9. Setting trouble-free policies for parental and sick leave.

    PubMed

    Hills, Laura Sachs

    2002-01-01

    Parental and sick leave are medical staff benefits that can lead to all kinds of problems. This article offers specific guidance for heading off the most common and difficult problems, focusing particularly on ways to provide fair benefits to employees who need them without inviting unnecessary absences and policy abuse. It reviews typical medical practice sick leave policies as well as four creative strategies for encouraging and rewarding excellent attendance and deterring abuse. In addition, this article suggests ways to structure a parental leave policy that will not only be fair to employees but also help the practice fulfill its legal obligations.

  10. [Improvement on microwave technology of extracting polysaccharide from yacon leaves].

    PubMed

    Li, Jing-wei; Liu, Jian; Yang, Yong; Zheng, Ming-min; Rong, Ting-zhao

    2007-11-01

    According to the extraction ratio of polysaccharide in yacon leaves, the comparison between microwave extraction and traditional hot water extraction was conducted, and the two-factor and three-level experiment on the microwave extraction of polysaccharide from yacon leaves was investigated. The result showed that the extraction ratio of polysaccharide by using microwave extraction was better than that by using traditional hot water extraction. Moreover, according to the result of variance analysis and multiple comparison, the optimum conditions for extraction of polysaccharide by using microwave technology from yacon leaves were as follows: 280W microwave power for 2 times and 15 minutes at every time.

  11. Why leaves turn red in autumn. The role of anthocyanins in senescing leaves of red-osier dogwood.

    PubMed

    Feild, T S; Lee, D W; Holbrook, N M

    2001-10-01

    Why the leaves of many woody species accumulate anthocyanins prior to being shed has long puzzled biologists because it is unclear what effects anthocyanins may have on leaf function. Here, we provide evidence for red-osier dogwood (Cornus stolonifera) that anthocyanins form a pigment layer in the palisade mesophyll layer that decreases light capture by chloroplasts. Measurements of leaf absorbance demonstrated that red-senescing leaves absorbed more light of blue-green to orange wavelengths (495-644 nm) compared with yellow-senescing leaves. Using chlorophyll a fluorescence measurements, we observed that maximum photosystem II (PSII) photon yield of red-senescing leaves recovered from a high-light stress treatment, whereas yellow-senescing leaves failed to recover after 6 h of dark adaptation, which suggests photo-oxidative damage. Because no differences were observed in light response curves of effective PSII photon yield for red- and yellow-senescing leaves, differences between red- and yellow-senescing cannot be explained by differences in the capacities for photochemical and non-photochemical light energy dissipation. A role of anthocyanins as screening pigments was explored further by measuring the responses PSII photon yield to blue light, which is preferentially absorbed by anthocyanins, versus red light, which is poorly absorbed. We found that dark-adapted PSII photon yield of red-senescing leaves recovered rapidly following illumination with blue light. However, red light induced a similar, prolonged decrease in PSII photon yield in both red- and yellow-senescing leaves. We suggest that optical masking of chlorophyll by anthocyanins reduces risk of photo-oxidative damage to leaf cells as they senesce, which otherwise may lower the efficiency of nutrient retrieval from senescing autumn leaves.

  12. Transcriptome phase distribution analysis reveals diurnal regulated biological processes and key pathways in rice flag leaves and seedling leaves.

    PubMed

    Xu, Wenying; Yang, Rendong; Li, Meina; Xing, Zhuo; Yang, Wenqiang; Chen, Guang; Guo, Han; Gong, Xiaojie; Du, Zhou; Zhang, Zhenhai; Hu, Xingming; Wang, Dong; Qian, Qian; Wang, Tai; Su, Zhen; Xue, Yongbiao

    2011-03-02

    Plant diurnal oscillation is a 24-hour period based variation. The correlation between diurnal genes and biological pathways was widely revealed by microarray analysis in different species. Rice (Oryza sativa) is the major food staple for about half of the world's population. The rice flag leaf is essential in providing photosynthates to the grain filling. However, there is still no comprehensive view about the diurnal transcriptome for rice leaves. In this study, we applied rice microarray to monitor the rhythmically expressed genes in rice seedling and flag leaves. We developed a new computational analysis approach and identified 6,266 (10.96%) diurnal probe sets in seedling leaves, 13,773 (24.08%) diurnal probe sets in flag leaves. About 65% of overall transcription factors were identified as flag leaf preferred. In seedling leaves, the peak of phase distribution was from 2:00am to 4:00am, whereas in flag leaves, the peak was from 8:00pm to 2:00am. The diurnal phase distribution analysis of gene ontology (GO) and cis-element enrichment indicated that, some important processes were waken by the light, such as photosynthesis and abiotic stimulus, while some genes related to the nuclear and ribosome involved processes were active mostly during the switch time of light to dark. The starch and sucrose metabolism pathway genes also showed diurnal phase. We conducted comparison analysis between Arabidopsis and rice leaf transcriptome throughout the diurnal cycle. In summary, our analysis approach is feasible for relatively unbiased identification of diurnal transcripts, efficiently detecting some special periodic patterns with non-sinusoidal periodic patterns. Compared to the rice flag leaves, the gene transcription levels of seedling leaves were relatively limited to the diurnal rhythm. Our comprehensive microarray analysis of seedling and flag leaves of rice provided an overview of the rice diurnal transcriptome and indicated some diurnal regulated biological

  13. A new prenylated biflavonoid from the leaves of Garcinia dulcis.

    PubMed

    Saelee, Arun; Phongpaichit, Souwalak; Mahabusarakam, Wilawan

    2015-01-01

    A new prenylated biflavonoid, named dulcisbiflavonoid A, together with five biflavonoids were isolated from the leaves of Garcinia dulcis. Their structures were elucidated by analysing their spectroscopic data, especially 1D and 2D NMR.

  14. Changes in spectral properties of detached birch leaves

    NASA Technical Reports Server (NTRS)

    Daughtry, C. S. T.; Biehl, L. L.

    1985-01-01

    A study conducted in order to determine the rate of changes in spectral properties of detached leaves and to evaluate the effectiveness of low temperature and cytokinins for delaying the changes, is examined. For five minutes, leaves from red birch are immersed in water or 0.001 M BAP, and then stored in plastic bags in the dark at either 5 or 25 C. Using a spectroradiometer and an integrating sphere, total directional-hemispherical reflectance and transmittance of the adaxial surface of the leaves are measured over the 400-1100 nm wavelength region. The results indicate that for leaves stored at 5 C for one week, the changes in the spectral properties are less than 5 percent of the initial values, whereas storage at 25 C promotes rapid senescence and large changes in the spectral properties. It is shown that low temperature is more effective than BAP in delaying senescence.

  15. A Legal Embarrassment: Paid Sick Leave for Pregnant Teachers

    ERIC Educational Resources Information Center

    Flygare, Thomas J.

    1978-01-01

    Although the denial of accrued sick leave for pregnancy is not per se illegal, school districts could make a very positive step toward equal opportunity by treating pregnancy the same as all other temporary disabilities. (Author/IRT)

  16. Eczema May Leave Some Flu Shots Less Effective, Study Finds

    MedlinePlus

    ... news/fullstory_163564.html Eczema May Leave Some Flu Shots Less Effective, Study Finds Vaccine should be ... MONDAY, Feb. 13, 2017 (HealthDay News) -- It's still flu season, and not too late to get your ...

  17. Phytochemical and termiticidal study of Lantana camara var. aculeata leaves.

    PubMed

    Verma, Rajesh K; Verma, Suman K

    2006-09-01

    Extracts of Lantana camara var. aculeata leaves were studied for their phytochemical constituents and termiticidal effects against adult termite workers. The 5% chloroform extract was found to be significantly effective against termite workers.

  18. Furoquinolines with antiplatelet aggregation activity from leaves of Melicope confusa.

    PubMed

    Chen, K S; Chang, Y L; Teng, C M; Chen, C F; Wu, Y C

    2000-02-01

    Using antiplatelet aggregation as a guide for fractionation, four furoquinoline-type alkaloids, confusameline (1), skimmianine (2), kokusaginine (3), and O-methylconfusameline (4), were isolated from the leaves of Melicope confusa. All compounds showed significant antiplatelet aggregation activity.

  19. Vine tendrils use contact chemoreception to avoid conspecific leaves.

    PubMed

    Fukano, Yuya

    2017-03-15

    Movement and growth habit of climbing plants have attracted attention since the time of Charles Darwin; however, there are no reports on whether plants can choose suitable hosts or avoid unsuitable ones based on chemoreception. Here, I show that the tendrils of Cayratia japonica (Vitaceae) appear to avoid conspecific leaves using contact chemoreception for oxalates, which are highly concentrated in C. japonica leaves. The coiling experiments show that C. japonica has a flexible plastic response to avoid coiling around conspecific leaves. The coiling response is negatively correlated with the oxalate content in the contacted leaves. Experiments using laboratory chemicals indicate that the tendrils avoid oxalate-coated plastic sticks. These results indicate that the tendrils of C. japonica avoid coiling around a conspecific leaf based on contact chemoreception for oxalate compounds. The tendrils of climbing plants may function as a chemoreceptor system to detect the chemical cues of a contacted plant.

  20. Effect of microbial fermentation on caffeine content of tea leaves.

    PubMed

    Wang, Xiaogang; Hu, Shuxia; Wan, Xiaochun; Pan, Caiyuan

    2005-09-07

    Caffeine is widely used in the food and pharmaceutical industries. For safety concerns, natural caffeine is preferred over synthetic products despite of its high cost. To explore more economical methods of acquiring natural caffeine, we adopted a microbial fermentation technique to increase the caffeine content of tea leaves. Our studies showed that the caffeine content in tea leaves increased reasonably after treating leaves with microorganisms for a period of time (i.e. orthodox pile-fermentation), and the amount of caffeine content increase varied significantly between black and green teas (27.57% and 86.41%). These results suggested that the change of caffeine content in tea leaves during the pile-fermentation depended not only on the growth and reproduction of microorganisms, but also on the tea composition.

  1. 29 CFR 825.301 - Designation of FMLA leave.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-qualifying must be based only on information received from the employee or the employee's spokesperson (e.g... should inquire further of the employee or the spokesperson to ascertain whether leave is potentially...

  2. Pharmacognostical studies on leaves of commiphora caudata (wight & arn) engl.

    PubMed

    Latha, S; Selvamani, P; Pal, T K; Gupta, J K; Ghosh, L K

    2006-07-01

    Commiphora caudata (Wight & Arn) is a potential medicinal plant used for its antispasmodic activity, cytotoxic activity and hypothermic activity. Owing to its medicinal importance, macroscopic and microscopic characters of leaves of Commiphora caudata were studied.

  3. Anti-diabetes constituents in leaves of Smallanthus sonchifolius.

    PubMed

    Xiang, Zheng; He, Fan; Kang, Ting-Guo; Dou, De-Qiang; Gai, Kuo; Shi, Yu-Yuan; Kim, Young-Ho; Dong, Feng

    2010-01-01

    The inhibitory effect of smallanthaditerpenic acids A, B, C and D previously isolated from leaves of Smallanthus sonchifolius (yacon) on alpha-glucosidase were examined and their IC50 were determined to be 0.48 mg/mL, 0.59 mg/mL, 1.00 mg/mL, and 1.17 mg/mL respectively. In addition, a rapid, reliable RP-HPLC method for the analysis of chlorogenic acid, caffeic acid, and smallanthaditerpenic acids A and C in yacon leaves was established, and the variation in their contents in leaves from plants cultivated in different places and collected at different times of the year were compared. The established analytical method for determining smallanthaditerpenic acids A and C, chlorogenic acid and caffeic acid presented good results and could be used as a method for the quality control of S. sonchifolius leaves.

  4. Keep on growing: building and patterning leaves in the grasses.

    PubMed

    Lewis, Michael W; Hake, Sarah

    2016-02-01

    Monocot leaves have unique features that arise early in their development. Maturing leaves protectively enclose younger leaves and the meristem, the pool of founder cells from which a leaf emerges. Through the maturation process, proximal sheath and distal blade tissues differentiate and are separated by the ligule and auricle structures. Here we review current research focusing on the contribution of gene regulatory factors and phytohormones on the patterning and differentiation of monocot leaves primarily focusing on research in the grasses (Poaceae). The 10000 members of the grasses include the true grain cereals (wheat, rice, maize, etc.), biofuel crops such as sugarcane, pasture grasses, and bamboo. They are the most studied of the monocots due to their tremendous agricultural and agronomic importance.

  5. Detail view of gauges that record pressure of gas leaving ...

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

    Detail view of gauges that record pressure of gas leaving the engine house. - Burnsville Natural Gas Pumping Station, Saratoga Avenue between Little Kanawha River & C&O Railroad line, Burnsville, Braxton County, WV

  6. Want to Leave Dinner Feeling Full? Bring on The Beans

    MedlinePlus

    ... to Leave Dinner Feeling Full? Bring on the Beans Vegetable patties make diners feel fuller than meat ... Jan. 11, 2016 (HealthDay News) -- Legumes such as beans and peas make people feel fuller after a ...

  7. Guajadial: an unusual meroterpenoid from guava leaves Psidium guajava.

    PubMed

    Yang, Xiao-Long; Hsieh, Kun-Lung; Liu, Ji-Kai

    2007-11-22

    Guajadial (1), a novel caryophyllene-based meroterpenoid, was isolated from the Leaves of Psidium guajava (guava). The structure and relative stereochemistry of guajadial (1) were elucidated by extensive spectroscopic analysis. A possible biosynthetic pathway for 1 was proposed.

  8. Compound leaves: equal to the sum of their parts?

    PubMed

    Champagne, Connie; Sinha, Neelima

    2004-09-01

    The leaves of seed plants can be classified as being either simple or compound according to their shape. Two hypotheses address the homology between simple and compound leaves, which equate either individual leaflets of compound leaves with simple leaves or the entire compound leaf with a simple leaf. Here we discuss the genes that function in simple and compound leaf development, such as KNOX1 genes, including how they interact with growth hormones to link growth regulation and development to cause changes in leaf complexity. Studies of transcription factors that control leaf development, their downstream targets, and how these targets are regulated are areas of inquiry that should increase our understanding of how leaf complexity is regulated and how it evolved through time.

  9. Managing overlapping federal FMLA and state leave regulations.

    PubMed

    Grebowski, Lucinda S

    2002-03-01

    The overlap between the Family and Medical Leave Act and state leave laws can create complications. Employers, particularly those with multistate operations, may wish to consider an outsourced absence management system, which can remove the burden of day-to-day administration and the need to stay abreast of changing state regulations. However, employers cannot outsource the responsibility to set broad policy toward absence management.

  10. Antibacterial Activity of Leaves of Cadaba trifoliata (Roxb.) Wt. & Arn.

    PubMed

    Mythreyi, R; Sasikala, E; Geetha, A; Madhavan, V

    2009-03-01

    Antibacterial activity of aqueous and ethanol leaf extracts of Cadaba trifoliata was evaluated by cup plate method against bacterial strains such as Staphylococcus aureus, Bacillus subtilis, Acinetobacter, Enterobacter aerogenes, Erwinia and Escherichia coli. The ethanol extract of the leaves demonstrated a high degree of activity against all the tested bacterial strains except Erwinia and Acinetobacter, whereas the aqueous extract of the leaves showed moderate activity against E. coli, B. subtilis and Staph. aureus and Enterobacter aerogenes.

  11. Thermal emissivity of leaves from trees cultivated using processed wastewater

    SciTech Connect

    Drakatos, P.A.; Kalavrouziotis, I.K.; Skuras, D.G.; Drakatos, S.P.

    1997-07-01

    Wastewater and sludge from wastewater treatment plans were discharged on experimental plantations of the species Nerium oleander, Eucalyptus sp. and Populus tremula. An emissiometer was used to measure the thermal emissitivity of the leaves of the different species. Comparison of thermal emissitivity between control and treatment leaves showed significant differences. There are clear indications that, land disposal of wastewater and sludge affects emissivity of different plant-species.

  12. 29 CFR 825.220 - Protection for employees who request leave or otherwise assert FMLA rights.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... FMLA leave, but discouraging an employee from using such leave. It would also include manipulation by a... to preclude the taking of leave; (3) Reducing hours available to work in order to avoid...

  13. 29 CFR 825.220 - Protection for employees who request leave or otherwise assert FMLA rights.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... FMLA leave, but discouraging an employee from using such leave. It would also include manipulation by a... to preclude the taking of leave; (3) Reducing hours available to work in order to avoid...

  14. Temporal heterogeneity of cold acclimation phenotypes in Arabidopsis leaves.

    PubMed

    Gorsuch, Peter A; Pandey, Subedar; Atkin, Owen K

    2010-02-01

    To predict the effects of temperature changes on plant growth and performance, it is crucial to understand the impact of thermal history on leaf morphology, anatomy and physiology. Here, we document a comprehensive range of leaf phenotypes in 25/20 degrees C-grown Arabidopsis thaliana plants that were shifted to 5 degrees C for up to 2 months. When warm-grown, pre-existing (PE) leaves were exposed to cold, leaf thickness increased due to an increase in mesophyll cell size. Leaves that were entirely cold-developed (CD) were twice as thick (eight cell layers) as their warm-developed (WD) counterparts (six layers), and also had higher epidermal and stomatal cell densities. After 4 d of cold, PE leaves accumulated high levels of total non-structural carbohydrates (TNC). However, glucose and starch levels declined thereafter, and after 45 d in the cold, PE leaves exhibited similar TNC to CD leaves. A similar phenomenon was observed in delta(13)C and a range of photosynthetic parameters. In cold-treated PE leaves, an increase in respiration (R(dark)) with cold exposure time was evident when measured at 25 degrees C but not 5 degrees C. Cold acclimation was associated with a large increase in the ratio of leaf R(dark) to photosynthesis. The data highlight the importance of understanding developmental thermal history in determining individual phenotypic traits.

  15. Detecting red blotch disease in grape leaves using hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Mehrubeoglu, Mehrube; Orlebeck, Keith; Zemlan, Michael J.; Autran, Wesley

    2016-05-01

    Red blotch disease is a viral disease that affects grapevines. Symptoms appear as irregular blotches on grape leaves with pink and red veins on the underside of the leaves. Red blotch disease causes a reduction in the accumulation of sugar in grapevines affecting the quality of grapes and resulting in delayed harvest. Detecting and monitoring this disease early is important for grapevine management. This work focuses on the use of hyperspectral imaging for detection and mapping red blotch disease in grape leaves. Grape leaves with known red blotch disease have been imaged with a portable hyperspectral imaging system both on and off the vine to investigate the spectral signature of red blotch disease as well as to identify the diseased areas on the leaves. Modified reflectance calculated at spectral bands corresponding to 566 nm (green) and 628 nm (red), and modified reflectance ratios computed at two sets of bands (566 nm / 628 nm, 680 nm / 738 nm) were selected as effective features to differentiate red blotch from healthy-looking and dry leaf. These two modified reflectance and two ratios of modified reflectance values were then used to train the support vector machine classifier in a supervised learning scheme. Once the SVM classifier was defined, two-class classification was achieved for grape leaf hyperspectral images. Identification of the red blotch disease on grape leaves as well as mapping different stages of the disease using hyperspectral imaging are presented in this paper.

  16. Spectra of normal and nutrient-deficient maize leaves

    NASA Technical Reports Server (NTRS)

    Al-Abbas, A. H.; Barr, R.; Hall, J. D.; Crane, F. L.; Baumgardner, M. F.

    1973-01-01

    Reflectance, transmittance and absorptance spectra of normal and six types of nutrient-deficient (N, P, K, S, Mg, and Ca) maize (Zea mays L.) leaves were analyzed at 30 selected wavelengths from 500 to 2600 nm. The analysis of variance showed significant differences in reflectance, transmittance and absorptance in the visible wavelengths among leaf numbers 3, 4, and 5, among the seven treatments, and among the interactions of leaf number and treatments. In the infrared wavelengths only treatments produced significant differences. The chlorophyll content of leaves was reduced in all nutrient-deficient treatments. Percent moisture was increased in S-, Mg-, and N-deficiencies. Polynomial regression analysis of leaf thickness and leaf moisture content showed that these two variables were significantly and directly related. Leaves from the P- and Ca-deficient plants absorbed less energy in the near infrared than the normal plants; S-, Mg-, K-, and N-deficient leaves absorbed more than the normal. Both S- and N-deficient leaves had higher temperatues than normal maize leaves.

  17. Nurse manager job satisfaction and intent to leave

    PubMed Central

    Warshawsky, Nora E.; Havens, Donna S.

    2015-01-01

    Background The nurse manager role is critical to staff nurse retention and often the portal to senior nursing leadership, yet little is known about nurse managers' job satisfaction and career plans. The purpose of this study was to describe nurse managers' job satisfaction and intent to leave. Methods An electronic survey was used to collect data from 291 nurse managers working in U.S. hospitals. Findings Seventy percent were satisfied or very satisfied with their jobs and 68% were either likely or very likely to recommend nursing management as a career choice. Seventy-two percent of these nurse managers were also planning to leave their positions in the next five years. The four most common reasons reported for intent to leave included burnout, career change, retirement, and promotion. Burnout was the most common reason cited by the entire sample but the fourth most common reason for leaving cited by those nurse managers who were planning to leave and also satisfied or very satisfied with their positions. Conclusions Recommendations for nursing leaders include evaluating the workload of nurse managers, providing career counseling, and developing succession plans. Additional research is needed to understand the determinants and consequences of nurse manager job satisfaction, intent to leave, and turnover. PMID:24689156

  18. Propensity to Leave versus Probability of Leaving: The Relationship between Intrinsic and Extrinsic Satisfaction in the Voluntary Leaving Behavior of IT Professionals

    ERIC Educational Resources Information Center

    King, Christopher S.

    2013-01-01

    This dissertation presents a quantitative analysis of the relationship between intrinsic and extrinsic job satisfaction and the voluntary leaving behavior of IT professionals. In addition, the study adds to the validity and reliability of the Udechukwu and Mujtaba Mathematical Turnover Model. Surveyed within the study for their intrinsic and…

  19. [Mechanism of cooked blanched garlic leaves against platelet aggregation].

    PubMed

    Wang, Xin-Hua; Di, Yan-Hui

    2014-06-01

    This study was purposed to explore the mechanism of cooked blanched garlic leave juice against platelet aggregation. The juice of blanched garlic leaves was mixed with platelet rich plasma (PRP), the human platelet aggregation, the activation of human platelets induced by adenosine diphosphate (ADP) and collagen were observed; the expression levels of the activated platelets (Fib-R) and P-selectin (CD62P), and the amount of platelet fibrinogen binding were detected by flow cytometry; 10 rabbits were randomly divided into two groups, in addition to the normal diet, they were fed with physiologic saline and cooked blanched garlic leave juice respectively. After 1, 3, 5 , 8 weeks, the maximum ratio of rabbit platelet aggregation induced by ADP and collagen were observed . The results showed that the cooked blanched garlic leave juice could significantly inhibit human platelet aggregation induced by ADP and collagen (P < 0.05), the inhibitory ratio were 87.37% and 86.24% respectively; the juice could not inhibit activated platelets Fib-R and CD62P expression levels (P > 0.05), but was able to inhibit platelet fibrinogen binding capacity (P < 0.05); the rabbit platelet aggregation rate in the group given cooked blanched garlic leave juice was significantly lower than that in control group (P < 0.05). It is concluded that the cooked blanched garlic leave juice can inhibit platelet aggregation in vitro and in vivo, the inhibition of aggregation pathway mainly is blocking the combination of fibrinogen with Fib-R, which finally results in the inhibition of platelet aggregation. Therefore, regular consumption of cooked blanched garlic leaves may prevent cardiovascular thrombotic diseases.

  20. Expanding leaves of mature deciduous forest trees rapidly become autotrophic.

    PubMed

    Keel, Sonja G; Schädel, Christina

    2010-10-01

    Emerging leaves in evergreen tree species are supplied with carbon (C) from the previous year's foliage. In deciduous trees, no older leaves are present, and the early phase of leaf development must rely on C reserves from other tissues. How soon developing leaves become autotrophic and switch from being C sinks to sources has rarely been studied in mature forest trees, and simultaneous comparisons of species are scarce. Using a canopy crane and a simple (13)CO(2)-pulse-labelling technique, we demonstrate that young leaves of mature trees in three European deciduous species (Fagus sylvatica L., Quercus petraea (Matt.) Liebl., Tilia platyphyllos Scop.) start assimilating CO(2) at a very early stage of development (10-50% expanded). One month after labelling, all leaves were still strongly (13)C enriched, suggesting that recent photosynthates had been incorporated into slow turnover pools such as cellulose or lignin and thus had contributed to leaf growth. In line with previous studies performed at the same site, we found stronger incorporation of recent photosynthates into growing tissues of T. platyphyllos compared with F. sylvatica and Q. petraea. Non-structural carbohydrate (NSC) concentrations analysed for one of the three study species (F. sylvatica) showed that sugar and starch pools rapidly increased during leaf development, suggesting that newly developed leaves soon produce more NSC than can be used for growth. In conclusion, our findings indicate that expanding leaves of mature deciduous trees become C autonomous at an early stage of development despite the presence of vast amounts of mobile carbohydrate reserves.

  1. GPs’ negotiation strategies regarding sick leave for subjective health complaints

    PubMed Central

    Malterud, Kirsti; Werner, Erik L; Maeland, Silje; Magnussen, Liv Heide

    2015-01-01

    Abstract Objectives. To explore general practitioners’ (GPs’) specific negotiation strategies regarding sick-leave issues with patients suffering from subjective health complaints. Design. Focus-group study. Setting. Nine focus-group interviews in three cities in different regions of Norway. Participants. 48 GPs (31 men, 17 women; age 32–65), participating in a course dealing with diagnostic practice and assessment of sickness certificates related to patients with subjective health complaints. Results. The GPs identified some specific strategies that they claimed to apply when dealing with the question of sick leave for patients with subjective health complaints. The first step would be to build an alliance with the patient by complying with the wish for sick leave, and at the same time searching for information to acquire the patient's perspective. This position would become the basis for the main goal: motivating the patient for a rapid return to work by pointing out the positive effects of staying at work, making legal and moral arguments, and warning against long-term sick leave. Additional solutions might also be applied, such as involving other stakeholders in this process to provide alternatives to sick leave. Conclusions and implications. GPs seem to have a conscious approach to negotiations of sickness certification, as they report applying specific strategies to limit the duration of sick leave due to subjective health complaints. This give-and-take way of handling sick-leave negotiations has been suggested by others to enhance return to work, and should be further encouraged. However, specific effectiveness of this strategy is yet to be proven, and further investigation into the actual dealings between doctor and patients in these complex encounters is needed. PMID:25602364

  2. A Global Regulation Inducing the Shape of Growing Folded Leaves

    PubMed Central

    Couturier, Etienne; Courrech du Pont, Sylvain; Douady, Stéphane

    2009-01-01

    Shape is one of the important characteristics for the structures observed in living organisms. Whereas biologists have proposed models where the shape is controlled on a molecular level [1], physicists, following Turing [2] and d'Arcy Thomson [3], have developed theories where patterns arise spontaneously [4]. Here, we propose that volume constraints restrict the possible shapes of leaves. Focusing on palmate leaves (with lobes), the central observation is that developing leaves first grow folded inside a bud, limited by the previous and subsequent leaves. We show that the lobe perimeters end at the border of this small volume. This induces a direct relationship between the way it was folded and the final unfolded shape of the leaf. These dependencies can be approximated as simple geometrical relationships that we confirm on both folded embryonic and unfolded mature leaves. We find that independent of their position in the phylogenetic tree, these relationships work for folded species, but do not work for non-folded species. This global regulation for the leaf growth could come from a mechanical steric constraint. Such steric regulation should be more general and considered as a new simple means of global regulation. PMID:19956690

  3. Degradation of phenanthrene on plant leaves by phyllosphere bacteria.

    PubMed

    Waight, Karen; Pinyakong, Onruthai; Luepromchai, Ekawan

    2007-10-01

    The activity of phyllosphere bacteria in the degradation of phenanthrene was investigated as a mechanism for the removal of atmospheric phenanthrene after its deposition on plant leaves. Initially, leaf samples of six plant species were collected from two roadsides in Bangkok to determine the presence of phenanthrene-degrading bacteria. The numbers of phenanthrene-degrading phyllosphere bacteria were varied and ranged from 3.5 x 10(4) to 1.95 x 10(7) CFU/g, in which the highest number was found from Ixora sp. Further studies were carried out in the laboratory by spraying phenanthrene on Ixora sp. leaves and then monitoring the amount of deposited phenanthrene and number of phenanthrene-degrading bacteria after incubation. The results showed that the amount of phenanthrene was significantly reduced on leaves containing phenanthrene-degrading bacteria. These were detected along with a rapid increase in the number of bacteria on leaves. The results indicated that many phyllosphere bacteria could utilize phenanthrene to support their growth and thereby reduce the amount of deposited phenanthrene on leaf surfaces. Several phenanthrene-degrading bacteria were later isolated from the leaves and identified with a high 16S rDNA sequence similarity to the genera Pseudomonas, Microbacterium, Rhizobium, and Deinococcus.

  4. [Origin of sennosides in health teas including Malva leaves].

    PubMed

    Kojima, T; Kishi, M; Sekita, S; Satake, M

    2001-06-01

    The aim of this study is to clarify whether sennosides are contained in the leaf of Malva verticillata L., and then to clarify the source of sennosides in health teas including malva leaves. The identification and determination of sennosides were performed with thin layer chromatography and high performance liquid chromatography. The leaf of Malva verticillata L. did not contain sennosides A or B and could be easily distinguished from senna leaf. Our previous report showed that sennosides are contained in weight-reducing herbal teas including malva leaves, and that senna leaf is a herbal component in some teas. Furthermore, in 10 samples of health tea including malva leaves that were bought last year, the smallest amount of sennosides was 6.1 mg/bag, and all health teas including malva leaves contained the leaf and midrib of senna. We suggest that sennosides A and B are not contained in the leaf of Malva verticillata L., and that the sennosides in health teas including malva leaves are not derived from malva leaf but from senna leaf.

  5. Oxalate Content of Taro Leaves Grown in Central Vietnam.

    PubMed

    Du Thanh, Hang; Phan Vu, Hai; Vu Van, Hai; Le Duc, Ngoan; Le Minh, Tuan; Savage, Geoffrey

    2017-01-01

    Leaves were harvested from four different cultivars of Colocasia esculenta and three cultivars of Alocasia odora that were growing on nine different farms in central Vietnam. The total, soluble and insoluble oxalate contents of the leaves were extracted and measured using HPLC chromatography. Total calcium determinations were also carried out on the same samples. The total oxalate content of the leaves ranged from 433.8 to 856.1 mg/100 g wet matter (WM) while the soluble oxalate ranged from 147.8 to 339.7 mg/100 g WM. The proportion of soluble oxalate ranged from 28% to 41% (overall mean 35%) of the total oxalate content of the leaves. The equivalent insoluble oxalate proportion ranged from 59% to 72% of the total (overall mean 65%). There was little difference between the Colocasia esculenta and Alocasia odora taro cultivars, although the total oxalate content was significantly higher in Alocasia odora cultivars. The overall mean total calcium content was 279.5 mg/100 WM and the percentage of insoluble calcium bound as calcium oxalate ranged from 31.7% to 57.3% of the total calcium content (overall mean 47.1%). The oxalate content in taro leaves is a major factor to consider when different cultivars of taro are recommended for human or animal consumption.

  6. Proteomic analysis of strawberry leaves infected with Colletotrichum fragariae.

    PubMed

    Fang, Xianping; Chen, Wenyue; Xin, Ya; Zhang, Hengmu; Yan, Chengqi; Yu, Hong; Liu, Hui; Xiao, Wenfei; Wang, Shuzhen; Zheng, Guizhen; Liu, Hongbo; Jin, Liang; Ma, Huasheng; Ruan, Songlin

    2012-07-16

    Understanding the defense mechanisms used by anthracnose-resistant strawberries against Colletotrichum infection is important for breeding purposes. To characterize cell responses to Colletotrichum infection, proteomes from strawberry seedling leaves that had or had not been infected with Colletotrichum fragariae were characterized at different time points post infection by 2-DE and by MALDI-TOF/TOF MS/MS and database-searching protein identification. Mass spectrometry identified 49 differentially expressed proteins with significant intensity differences (>1.5-fold, p<0.05) in mock- and C. fragariae-infected leaves at least at one time point. Notably, 2-DE analysis revealed that C. fragariae infection increased the expression of well-known and novel pathogen-responsive proteins whose expression patterns tended to correlate with physiological changes in the leaves. Quantitative real-time PCR was used to examine the transcriptional profiles of infected and uninfected strawberry leaves, and western blotting confirmed the induction of β-1,3-glucanase and a low-molecular-weight heat shock protein in response to C. fragariae infection. During the late phase of infection, proteins involved in the Calvin cycle and glycolysis pathway had suppressed expression. The abundance changes, putative functions, and participation in physiological reactions for the identified proteins produce a pathogen-responsive protein network in C. fragariae-infected strawberry leaves. Together, these findings increase our knowledge of pathogen resistance mechanisms, especially those found in non-model plant species.

  7. Drying kinetics of dill leaves in a convective dryer

    NASA Astrophysics Data System (ADS)

    Motevali, A.; Younji, S.; Chayjan, R. Amiri; Aghilinategh, N.; Banakar, A.

    2013-01-01

    Thin layer drying characteristics of dill leaves under fixed, semi-fluidized, and fluidized bed conditions were studied at air temperatures of 30, 40, 50, and 60°C. In order to find a suitable drying curve, 12 thin layer-drying models were fitted to the experimental data of the moisture ratio. Among the applied mathematical models, the Midilli et al. model was the best for drying behavior prediction in thin layer drying of dill leaves. To obtain the optimum network for drying of dill leaves, various numbers of multilayer feed-forward neural networks were made and tested with different numbers of hidden layers and neurons. The best neural network feed-forward back-propagation topology for the prediction of drying of dill leaves (moisture ratio and drying rate) was the 3-45-2 structure with the training algorithm trainlm and threshold functions logsig and purelin. The coefficient of determination for this topology for training, validation, and testing patterns was 0.9998, 0.9981, and 0.9990, respectively. Effective moisture diffusivity of dill leaves during the drying process in different bed types was found to be in the range from 7.10 10-12 to 1.62 10-10 m2 s-1. Also, the values of activation energy were determined to be between 75.435 and 80.118 kJ mol-1

  8. Oxalate Content of Taro Leaves Grown in Central Vietnam

    PubMed Central

    Du Thanh, Hang; Phan Vu, Hai; Vu Van, Hai; Le Duc, Ngoan; Le Minh, Tuan; Savage, Geoffrey

    2017-01-01

    Leaves were harvested from four different cultivars of Colocasia esculenta and three cultivars of Alocasia odora that were growing on nine different farms in central Vietnam. The total, soluble and insoluble oxalate contents of the leaves were extracted and measured using HPLC chromatography. Total calcium determinations were also carried out on the same samples. The total oxalate content of the leaves ranged from 433.8 to 856.1 mg/100 g wet matter (WM) while the soluble oxalate ranged from 147.8 to 339.7 mg/100 g WM. The proportion of soluble oxalate ranged from 28% to 41% (overall mean 35%) of the total oxalate content of the leaves. The equivalent insoluble oxalate proportion ranged from 59% to 72% of the total (overall mean 65%). There was little difference between the Colocasia esculenta and Alocasia odora taro cultivars, although the total oxalate content was significantly higher in Alocasia odora cultivars. The overall mean total calcium content was 279.5 mg/100 WM and the percentage of insoluble calcium bound as calcium oxalate ranged from 31.7% to 57.3% of the total calcium content (overall mean 47.1%). The oxalate content in taro leaves is a major factor to consider when different cultivars of taro are recommended for human or animal consumption. PMID:28231080

  9. Antioxidant Activity of Leaves and Fruits of Iranian Conifers

    PubMed Central

    Emami, S. A.; Asili, J.; Mohagheghi, Z.

    2007-01-01

    Cupressus semipervirens var. horizontalis, Cupressus semipervirens var. semipervirens, Cupressus semipervirens cv. Cereifeormis, Juniperus communis subsp. hemisphaerica, Juniperus excelsa subsp. excelsa, Juniperus excelsa subsp. polycarpos, Juniperus foetidissima, Juniperus oblonga, Juniperus sabina, Platycladus orientalis and Taxus baccata are Iranian conifers. The antioxidant activity of leaves and fruits of these 11 different taxons were evaluated. The leaves of both male and female, and fruits of these plants were collected from different areas of the country. Methanol extract of leaves and fruits of these taxons were prepared. Antioxidant activity of each extracts was measured using two different tests of the ferric thiocyanate method and thiobarbituric acid. Results indicated that the methanol extracts of leaves, of male and female, and fruits of all these species (27 samples) possessed antioxidant activity when tested with both methods. The antioxidant activity was then compared with those of α-tocopherol (a natural antioxidant) and butylated hydroxytoluene (a synthetic antioxidant). Methanol extract of fruits of C. semipervirens cv. Cereifeormis showed the highest antioxidant activity while the methanol extract of leaves of C. semipervirens var. semipervirens possessed the lowest antioxidant activity. However, our finding showed that most of the tested extracts were showing strong antioxidant activity even higher than α-tocopherol. PMID:17965761

  10. Isoprene increases thermotolerance of fosmidomycin-fed leaves.

    PubMed

    Sharkey, T D; Chen, X; Yeh, S

    2001-04-01

    Isoprene is synthesized and emitted in large amounts by a number of plant species, especially oak (Quercus sp.) and aspen (Populus sp.) trees. It has been suggested that isoprene improves thermotolerance by helping photosynthesis cope with high temperature. However, the evidence for the thermotolerance hypothesis is indirect and one of three methods used to support this hypothesis has recently been called into question. More direct evidence required new methods of controlling endogenous isoprene. An inhibitor of the deoxyxylulose 5-phosphate pathway, the alternative pathway to the mevalonic acid pathway and the pathway by which isoprene is made, is now available. Fosmidomycin eliminates isoprene emission without affecting photosynthesis for several hours after feeding to detached leaves. Photosynthesis of fosmidomycin-fed leaves recovered less following a 2-min high-temperature treatment at 46 degrees C than did photosynthesis of leaves fed water or fosmidomycin-fed leaves in air supplemented with isoprene. Photosynthesis of Phaseolus vulgaris leaves, which do not make isoprene, exhibited increased thermotolerance when isoprene was supplied in the airstream flowing over the leaf. Other short-chain alkenes also improved thermotolerance, whereas alkanes reduced thermotolerance. It is concluded that thermotolerance of photosynthesis is a substantial benefit to plants that make isoprene and that this benefit explains why plants make isoprene. The effect may be a general hydrocarbon effect and related to the double bonds in the isoprene molecule.

  11. Persistence and metabolism of fipronil in sugarcane leaves and juice.

    PubMed

    Mandal, Kousik; Singh, Balwinder

    2014-02-01

    Fipronil gives effective control of early shoot borer and termites in sugarcane. The persistence and metabolism of fipronil in sugarcane leaves and juice were studied following application of fipronil (Regent 0.3 G) at 75 and 300 g a.i. ha(-1). Samples of sugarcane leaves were collected at various time intervals. Samples of sugarcane juice were collected at harvest. Residues of fipronil and its metabolites were quantified by gas liquid chromatograph. The limit of quantification of fipronil and its metabolites was 0.01 mg kg(-1) for sugarcane leaves and juice. Total residues of fipronil and its metabolites in sugarcane leaves after 7 days of its application at 75 and 300 g a.i. ha(-1) were 0.26 and 0.66 mg kg(-1), respectively. Residues could not be detected after 60 and 90 following fipronil application at either concentration. In sugarcane leaves, fipronil was found to be the main constituent, followed by its metabolites amide, desulfinyl, sulfone and sulfide. Samples of sugarcane juice did not reveal the presence of fipronil or its metabolites following its application at both the dosages at harvest.

  12. Iprodione residues and dissipation rates in tobacco leaves and soil.

    PubMed

    Wang, Xiuguo; Xu, Guangjun; Wang, Fenglong; Sun, Huiqing; Li, Yiqiang

    2012-10-01

    Field experiments were conducted in two different locations to determine the residue levels and dissipation rates of iprodione in tobacco leaves and soil. Iprodione 50% wettable powder formulation was sprayed once at 12.50 g/ha to study the dissipation behavior and three to four times at 8.33 g/ha (recommended dose) and 12.50 g/ha (1.5 times the recommended field dose) to determine the residue levels of iprodione in tobacco leaves and soil after repeated applications. Iprodione residues in both green tobacco leaves and soil dissipated to about 50% of the initial deposits after 7 days and then further dissipated to more than 90% after 35 days.The dissipation of iprodione followed first order kinetics and the calculated half-life values (T (1/2)) were 5.64-8.80 days in green tobacco leaves and 7.50-9.93 days in soil, respectively. Iprodione residue levels in flue-cured tobacco leaves 21 days after the third and fourth applications ranged from 7.61 to 40.98 mg/kg. Meanwhile, the residues detected in soil decreased to 0.010-0.117 mg/kg 21 days after the last treatment.

  13. Uptake and transformation of benzene and toluene by plant leaves.

    PubMed

    Ugrekhelidze, D; Korte, F; Kvesitadze, G

    1997-06-01

    The [1-6(14)C]benzene and [1-(14)C]toluene vapors penetrate into hypostomatous leaves of Acer campestre, Malus domestica, and Vitis vinifera from both sides, whereas hydrocarbons are more intensively absorbed by the stomatiferous side and more actively taken up by young leaves. Benzene and toluene conversion in leaves occurs with the aromatic ring cleavage and their carbon atoms are mainly incorporated into nonvolatile organic acids, while their incorporation into amino acids is less intensive. Intact spinach chloroplasts oxidize benzene, and this process is strongly stimulated in light. Oxidation of benzene by spinach chloroplasts or by enzyme preparation from spinach leaves is almost completely inhibited by 8-oxyquinoline or sodium diethyldithiocarbamate, and slightly affected by alpha, alpha'-dipyridyl. Benzene oxidation by enzyme preparation is significantly stimulated by NADH and NADPH; in their presence, the benzene hydroxylation product, phenol, is formed in a determinable amount. It is supposed that the enzyme performing the first step of oxidative transformation of benzene in plant leaves contains copper as the prosthetic group.

  14. Antimicrobial activity of extracts from Tamarindus indica L. leaves

    PubMed Central

    Escalona-Arranz, Julio César; Péres-Roses, Renato; Urdaneta-Laffita, Imilci; Camacho-Pozo, Miladis Isabel; Rodríguez-Amado, Jesús; Licea-Jiménez, Irina

    2010-01-01

    Tamarindus indica L. leaves are reported worldwide as antibacterial and antifungal agents; however, this observation is not completely accurate in the case of Cuba. In this article, decoctions from fresh and sun dried leaves, as well as fluid extracts prepared with 30 and 70% ethanol-water and the pure essential oil from tamarind leaves were microbiologically tested against Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Pseudomona aeruginosa and Candida albicans. Aqueous and fluid extracts were previously characterized by spectrophotometric determination of their total phenols and flavonoids, while the essential oil was chemically evaluated by gas chromatography/mass spectroscopy (GC/MS). Experimental data suggest phenols as active compounds against B. subtilis cultures, but not against other microorganisms. On the other hand, the essential oil exhibited a good antimicrobial spectrum when pure, but its relative low concentrations in common folk preparations do not allow for any good activity in these extracts. PMID:20931087

  15. Genetic variation in alkaloid accumulation in leaves of Nicotiana.

    PubMed

    Sun, Bo; Zhang, Fen; Zhou, Guo-jun; Chu, Guo-hai; Huang, Fang-fang; Wang, Qiao-mei; Jin, Li-feng; Lin, Fu-cheng; Yang, Jun

    2013-12-01

    Alkaloids are plant secondary metabolites that are widely distributed in Nicotiana species and contribute greatly to the quality of tobacco leaves. Some alkaloids, such as nornicotine and myosmine, have adverse effects on human health. To reduce the content of harmful alkaloids in tobacco leaves through conventional breeding, a genetic study of the alkaloid variation among different genotypes is required. In this study, alkaloid profiles in leaves of five Nicotiana tabacum cultivars and Nicotiana tomentosiformis were investigated. Six alkaloids were identified from all six genotypes via gas chromatograph-mass spectrometry (GC-MS). Significant differences in alkaloid content were observed both among different leaf positions and among cultivars. The contents of nornicotine and myosmine were positively and significantly correlated (R(2)=0.881), and were also separated from those of other alkaloids by clustering. Thus, the genotype plays a major role in alkaloid accumulation, indicating a high potential for manipulation of alkaloid content through traditional breeding.

  16. Ginkgo biloba leave extract: biological, medicinal, and toxicological effects.

    PubMed

    Chan, Po-Chuen; Xia, Qingsu; Fu, Peter P

    2007-01-01

    Ginkgo biloba leave extract is among the most widely sold herbal dietary supplements in the United States. Its purported biological effects include: scavenging free radical; lowering oxidative stress; reducing neural damages, reducing platelets aggregation; anti-inflammation; anti-tumor activities; and anti-aging. Clinically, it has been prescribed to treat CNS disorders such as Alzheimer's disease and cognitive deficits. It exerts allergy and changes in bleeding time. While its mutagenicity or carcinogenic activity has not been reported, its components, quercetin, kaempferol and rutin have been shown to be genotoxic. There are no standards or guidelines regulating the constituent components of Ginkgo biloba leave extract nor are exposure limits imposed. Safety evaluation of Ginkgo biloba leave extract is being conducted by the U.S. National Toxicology Program.

  17. Falling Leaves, Flapping Flight, and Making a Virtual Insect

    NASA Astrophysics Data System (ADS)

    Wang, Z. Jane

    2004-03-01

    Insects are fascinating to watch but difficult to catch, so are falling leaves. The diverse maneuver executed by insects and the flutter and tumbling motion of leaves are manifestations of complex interactions between the moving surfaces and the surrounding unsteady air. Despite the long tradition in fluid dynamics, relatively few quantitative descriptions and basic mechanisms are known about these two everyday phenomena. In this talk, I will describe some of the lessons we learned by analyzing them. In particular, I will show 1)a basic two dimensional mechanism of insect hovering and the associated vortical flow and forces, 2) the use of drag in insect hovering, in contrast to helicopter,3) the rise of falling leaves and the lift mechanism which is responsible for the center of mass elevation, 4) a model of fluid forces, different from the classical theory, for falling objects in fluid, and 5) computer experiments of three dimensional elastic flapping wings driven by muscles.

  18. PROFILE OF PATIENTS ON SICK LEAVE WITH CARPAL TUNNEL SYNDROME

    PubMed Central

    de Azevedo, Judson Welber Veríssimo; de Oliveira, Alexandre Barbosa; Nascimento, Valdênia das Graças; de Paiva, Henver Ribeiro; Viecili, Leandro; Rocha, Murilo Antonio

    2015-01-01

    ABSTRACT Objective: To report clinical and epidemiological characteristics and risk factors of patients with Carpal Tunnel Syndrome (CTS) on sick leave admitted in a University Hospital. Methods: This is a transversal study conducted with patients admitted sequentially over 18 years of age, without distinction of gender and race in the period between September and November 2014. Patients answered a questionnaire and underwent physical examination carried out by the authors. Results: Twenty-five patients were admitted within three months, all females, the mean age was 50.24 years old (standard deviation 10,39) . Among the professions they performed, general and cleaning services were the most prevalent. Most patients featured obesity, followed by depression and systemic arterial hypertension. Approximately half of them were on sick leave. Sleep disorders were also a frequent complaint. Conclusion: CTS is a frequent cause of sick leave and it is related to obesity, dyslipidemia and depression. Level of Evidence IV, Series of Cases. PMID:26981030

  19. Effects of exogenous glucose on carotenoid accumulation in tomato leaves.

    PubMed

    Mortain-Bertrand, Anne; Stammitti, Linda; Telef, Nadège; Colardelle, Patrice; Brouquisse, Renaud; Rolin, Dominique; Gallusci, Philippe

    2008-10-01

    To investigate the effect of carbohydrate on carotenoid accumulation in leaves, excised plants of tomato (Lycopersicum esculentum var. cerasiformae, wva 106) were supplied with glucose through the transpiration stream for 48 h. We report here that sugar accumulation in leaves led to a decrease of carotenoid content, which was related to the reduction of Chl. The decrease in carotenoid amount correlated with a sugar-induced repression of genes encoding enzymes of the carotenoid and of the Rohmer pathways. The lower 1-deoxy-D-xylulose-5-phosphate synthase transcript level probably leads to a decreased metabolic flux through the methylerythritol pathway and subsequently to a lower amount of substrate available for plastidic isoprenoid synthesis. Differences between responses of young (sink) and mature (source) leaves to carbohydrate accumulation are discussed.

  20. Confirmation of a purple-leaved plum graft hybrid.

    PubMed

    Zhou, X M; Liu, Y S; Li, X J

    2013-03-11

    Fifty-seven scions from an adult purple-leaved plum tree were grafted onto the crown of a 6-year-old Yuhuang plum tree and compared to the control of a non-grafted tree. The floral buds of the purple-leaved plum were fully removed before blossoming to avoid sexual hybridization between the two species. The seeds of the Yuhuang plum were picked in July and sown in the spring after stratification. Three, eleven and eight variants with purplish red leaves were found among the seedlings that grew from the seeds picked in 1999, 2000, and 2001, respectively. The ratio of variant occurrence ranged from 2.3 to 15.8%. Our results confirmed the observation of a graft hybrid by Luther Burbank.

  1. Anticomplement activity of polyacetylenes from leaves of Dendropanax morbifera Leveille.

    PubMed

    Chung, Ill-Min; Song, Hong-Keun; Kim, Sun-Jin; Moon, Hyung-In

    2011-05-01

    The present study evaluated the anticomplement effect of polyacetylenes from Dendropanax morbifera (Araliaceae) in the classical pathway complement system. The leaves of D. morbifera were evaluated with regard to its anticomplement activity, and its active principles identified following activity-guided isolation. An aqueous CCl(4) fraction of the leaves of D. morbifera exhibited significant anticomplement activity on the classical pathway complement system, which was expressed as total hemolytic activity. Three polyacetylenes isolated from the leaves of D. morbifera, namely (3S)-falcarinol (1), (3S,8S)-falcarindiol (2) and (3S)-diynene (3). Compounds 1, 2 and 3 showed inhibitory activity against complement system with 50% inhibitory concentrations (IC(50)) values of 87.3 µM, 15.2 µM and 39.8 µM. Among the compounds tested, 2 showed the most potent anticomplement activity (IC(50), 15.2 µM).

  2. Secondary Metabolites from Leaves of Manilkara subsericea (Mart.) Dubard

    PubMed Central

    de Almeida, Fernanda Borges; Fernandes, Caio Pinho; Romao, Wanderson; Vanini, Gabriela; Costa, Helber Barcelos; França, Hildegardo Seibert; Santos, Marcelo Guerra; Carvalho, José Carlos Tavares; Falcão, Deborah Quintanilha; Rocha, Leandro

    2015-01-01

    Background: Manilkara subsericea (Sapotaceae) is a species widely spread in the sandbanks of Restinga de Jurubatiba National Park (Rio de Janeiro, Brazil). It is commonly known as “maçaranduba”, “maçarandubinha” and “guracica”, being used in this locality as food, and timber. However, M. subsericea remains almost unexplored regarding its chemical constituents, including secondary metabolites from the leaves. Objective: Identify the chemical constituents from the leaves of M. subsericea. Materials and Methods: Leaves were macerated with ethanol (96% v/v), and dried crude ethanolic extract was sequentially washed with the organic solvents in order to obtain an ethyl acetate fraction. Substances from this fraction were identified by different techniques, such as negative-ion electrospray ionization Fourier and 1H and 13C nuclear magnetic resonance (NMR). Fresh leaves from M. subsericea were also submitted to hydrodistillation in order to obtain volatile substances, which were identified by gas chromatograph coupled to mass spectrometer. Results: NMR1H and 13C spectra allowed for the identification of the compounds myricetin, quercetin, and kaempferol from the ethyl acetate fraction. The negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry mass spectrum also revealed the presence in this fraction of a polyhydroxytriterpene acid (pomolic acid), and some flavonoids, such as quercitrin, and myricitrin. In all 34 volatile compounds were identified by gas chromatography-mass spectrometry, including monoterpenes, sesquiterpenes, and long chain hydrocarbons. Conclusion: This study describes the first reports concerning the phytochemical information about leaves from M. subsericea. SUMMARY Manilkara subsericea fruits proved to be a rich source of triterpenes. However, no phytochemical studies were carried out with leaves. Thus, we described identification of volatile substances from its essential oils, in addition to

  3. International policies toward parental leave and child care.

    PubMed

    Waldfogel, J

    2001-01-01

    The pleasures and pressures of parenting a newborn are universal, but the supports surrounding parents vary widely from country to country. In many nations, decades of attention to benefits and services for new parents offer lessons worthy of attention in this country. This article describes policies regarding parental leave, child care, and early childhood benefits here and in 10 industrial nations in North America and Europe. The sharpest contrast separates the United States from the other countries, although differences among the others also are instructive: The right to parental leave is new to American workers; it covers one-half of the private-sector workforce and is relatively short and unpaid. By contrast, other nations offer universal, paid leaves of 10 months or more. Child care assistance in Europe is usually provided through publicly funded programs, whereas the United States relies more on subsidies and tax credits to reimburse parents for part of their child care expenses. Nations vary in the emphasis they place on parental leave versus child care supports for families with children under age three. Each approach creates incentives that influence parents' decisions about employment and child care. Several European nations, seeking flexible solutions for parents, are testing "early childhood benefits" that can be used to supplement income or pay for private child care. Based on this review, the author urges that the United States adopt universal, paid parental leave of at least 10 months; help parents cover more child care costs; and improve the quality of child care. She finds policy packages that support different parental choices promising, because the right mix of leave and care will vary from family to family, and child to child.

  4. [Beijing common green tree leaves' accumulation capacity for heavy metals].

    PubMed

    Li, Shao-Ning; Kong, Ling-Wei; Lu, Shao-Wei; Chen, Bo; Gao, Chen; Shi, Yuan

    2014-05-01

    Seasonal variation of heavy metal contents in leaves and their relationships with soil heavy metal pollution levels were studied through measuring and analyzing the leaves of the common tree species in Beijing and soil heavy metal contents, to detect heavy metal accumulation ability of plant leaves. The results showed that: (1) the contents of Cu, Pb, Zn in plant leaves first decreased and then increased, again declined with changing the seasons (from spring to winter). Cr concentration showed the trend of first increase and then decrease from spring to winter, and the highest in the autumn; the accumulation capacities of Cu for Babylonica and Japonica were higher in the spring, summer and autumn, while Tabuliformis was in winter; the higher accumulation capacities for Cr, Pb were Japonica and Platycladus, and in winter were Platycladus and Bungeana; the higher accumulation capacities for Zn were Babylonica and Bungeana, while Platycladus in winter; (2) the pollution degree of four kinds of heavy metals (Cu, Cr, Pb, Zn) from downtown to suburbs showed that: Jingshan (C =2.48, C is contamination factor) > Olympic (C = 1.27) > Songshan (C = 1.20) > Shuiguan (C = 1. 18); (3) the heavy metals concentration of same plant leaves in the water of the Great Wall changed larger, but those in the other three areas showed that: Jingshan > Olympic > Songshan; the ability of same species leaf to absorb different sorts of heavy metals showed that: Zn >Cu >Pb >Cr; the difference between Zn content and Cr content was significant (P <0.01); (4) the relationship between heavy metal content in plant leaves and soil heavy metal pollution levels presented a quadratic polynomial relation; the significant correlation was found between other three heavy metal contents of plant samples and soil samples, but they were not the case for the Cu, and the correlation coefficients were above 0. 9.

  5. To Stay or to Leave: Factors Influencing Victims' Decisions to Stay or Leave a Domestic Violence Emergency Shelter.

    PubMed

    Fisher, Elisa M; Stylianou, Amanda M

    2016-04-28

    Domestic violence (DV) emergency shelters play a vital role in supporting victims who seek to leave abusive partners and gain independence. Research indicates that numerous positive outcomes for victims and their children are associated with utilization of DV shelter programs. Yet, research also suggests that DV shelter programs may be unable to comprehensively meet the needs of all victims, and many choose to leave shelters soon after their arrival. To better understand the ways in which DV shelter programs support victims but also fail to meet their needs, this article explores the factors that influence victims' decisions to stay or leave a DV emergency shelter program through qualitative interviews with 33 DV shelter residents. Study participants indicate that three types of factors influence their decision to stay or leave the shelter program: (a) contextual factors, (b) partner or family relationship factors, and (c) shelter-specific factors. Shelter-specific factors cited as important contributors to satisfaction or dissatisfaction with shelter living include policies, staff and services, displacement from one's home community, and facilities. Findings provide information from the perspective of victims on the factors that influence one's decision to stay or leave a DV program and can be used to support service providers and advocates in building programs that are both supportive of victims' needs and conductive to longer shelter stays.

  6. Nest Leaving in Sweden: The Importance of Early Educational and Labor Market Careers.

    ERIC Educational Resources Information Center

    Nilsson, Karina; Strandh, Mattias

    1999-01-01

    Study looked at the importance of early education and labor market careers for nest leaving and returning to the parental home. The data determined that employment means a high probability of nest leaving but less stability of independent living. The early career was more important for structuring women's nest leaving than men's nest leaving.…

  7. Students with Special Educational Needs in Secondary Education: Are They Intending to Learn or to Leave?

    ERIC Educational Resources Information Center

    Pijl, Sip Jan; Frostad, Per; Mjaavatn, Per Egil

    2014-01-01

    During their secondary school years, a considerable number of students seriously consider choosing between learning and leaving. Leaving school early means that students do not complete their education. Early school leaving is the last step in a process in which students gradually lose interest and develop the intention to leave school. This study…

  8. 5 CFR 630.1014 - Movement between voluntary leave bank programs.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Movement between voluntary leave bank programs. 630.1014 Section 630.1014 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1014 Movement between voluntary leave...

  9. 5 CFR 630.1014 - Movement between voluntary leave bank programs.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Movement between voluntary leave bank programs. 630.1014 Section 630.1014 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1014 Movement between voluntary leave...

  10. 5 CFR 630.1014 - Movement between voluntary leave bank programs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Movement between voluntary leave bank programs. 630.1014 Section 630.1014 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1014 Movement between voluntary leave...

  11. 5 CFR 630.1014 - Movement between voluntary leave bank programs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Movement between voluntary leave bank programs. 630.1014 Section 630.1014 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1014 Movement between voluntary leave...

  12. 5 CFR 630.1014 - Movement between voluntary leave bank programs.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Movement between voluntary leave bank programs. 630.1014 Section 630.1014 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1014 Movement between voluntary leave...

  13. Bioethanol production from Ficus religiosa leaves using microwave irradiation.

    PubMed

    Klein, Miri; Griess, Ofir; Pulidindi, Indra Neel; Perkas, Nina; Gedanken, Aharon

    2016-07-15

    A microwave assisted feasible process for the production of bioethanol from Ficus religiosa leaves was developed. Under the process conditions (8 min. microwave irradiation, 1 M HCl), 10.1 wt% glucose yield was obtained from the leaves. Microwave based hydrolysis process yielded higher glucose content (10.1 wt%) compared to the conventional hydrothermal process (4.1 wt%). Upon fermentation of the hydrolysate using Baker's yeast, 3 wt% (dry wt. basis) of bioethanol was produced.

  14. Is There Spectral Variation in the Polarized Reflectance of Leaves?

    NASA Technical Reports Server (NTRS)

    Vanderbilt, V. C.; Daughtry, C. S. T.; Biehl, L. L.

    2014-01-01

    The light scattered by plant canopies depends in part on the light scattering/absorbing properties of the leaves and is key to understanding the remote sensing process in the optical domain. Here we specifically looked for evidence of fine spectral detail in the polarized portion of the light reflected from the individual leaves of five species of plants measured at Brewsters angle over the wavelength range 450 to 2300nm. Our results show no strong, unambiguous evidence of narrow band spectral variation of the polarized portion of the reflectance factor.

  15. Is there Spectral Variation in the Polarized Reflectance of Leaves?

    NASA Technical Reports Server (NTRS)

    Vanderbilt, V. C.; Daughtry, C. S. T.; Biehl, L. L.

    2014-01-01

    The light scattered by plant canopies depends in part on the light scattering/absorbing properties of the leaves and is key to understanding the remote sensing process in the optical domain. Here we specifically looked for evidence of fine spectral detail in the polarized portion of the light reflected from the individual leaves of five species of plants measured at Brewsters angle over the wavelength range 450 to 2300nm. Our results show no strong, unambiguous evidence of narrow band spectral variation of the polarized portion of the reflectance factor.

  16. Immediate IPTV channel leave by explicit user tracking in PON

    NASA Astrophysics Data System (ADS)

    Zhu, Peng; Yoshiuchi, Hideya; Yoshizawa, Satoshi

    2007-11-01

    In this paper, we propose a novel IPTV channel leave mechanism for Passive Optical Network (PON). By explicit user tracking and automatic differentiation of IGMP v2 and v3 users, the proposed mechanism can realize immediate channel leave in both Optical Line Terminal (OLT) and Optical Network Unit (ONU) while avoiding removing the channel which still has users. Simulation results show that the proposed mechanism can significantly save the bandwidth consumption during "channel surf" by users, compared to the standard IGMP timeout mechanism.

  17. Cyanide-induced death of cells in plant leaves.

    PubMed

    Vasil'ev, L A; Vorobyov, A A; Dzyubinskaya, E V; Nesov, A V; Shestak, A A; Samuilov, V D

    2007-05-01

    Destruction of guard cell nuclei in epidermis isolated from leaves of pea, maize, sunflower, and haricot bean, as well as destruction of cell nuclei in leaves of the aquatic plants waterweed and eelgrass were induced by cyanide. Destruction of nuclei was strengthened by illumination, prevented by the antioxidant alpha-tocopherol and an electron acceptor N,N,N ,N -tetramethyl-p-phenylenediamine, and removed by quinacrine. Photosynthetic O2 evolution by the leaf slices of a C3 plant (pea), or a C4 plant (maize) was inhibited by CN- inactivating ribulose-1,5-bisphosphate carboxylase, and was renewed by subsequent addition of the electron acceptor p-benzoquinone.

  18. The uptake of elemental iodine vapour by bean leaves

    NASA Astrophysics Data System (ADS)

    Garland, J. A.; Cox, L. C.

    Deposition of iodine vapour to leaves of phaseolus vulgaris was measured over a range of conditions of humidity, temperature and illumination. Transpiration measurements were used to deduce stomatal opening. The results showed that stomatal resistance controlled iodine absorption at relative humidities below 40 per cent, but that the rate of absorption of iodine increased by an order of magnitude when the relative humidity was raised to 80 per cent, presumably due to cuticular absorption. After exposure to iodine at high humidity, a substantial fraction of the iodine could be washed from the leaves. In Britain, cuticular uptake would probably dominate stomatal uptake of iodine on most occasions.

  19. Extraction and identification of bioactive compounds from agarwood leaves

    NASA Astrophysics Data System (ADS)

    Lee, N. Y.; Yunus, M. A. C.; Idham, Z.; Ruslan, M. S. H.; Aziz, A. H. A.; Irwansyah, N.

    2016-11-01

    Agarwood commonly known as gaharu, aloeswood or eaglewood have been used as traditional medicine for centuries and its essential oil also being used as perfumery ingredients and aroma enhancers in food products. However, there is least study on the agarwood leaves though it contains large number of biomolecules component that show diverse pharmacological activity. Previous study showed that the extracted compounds from the leaves possess activities like anti-mutagenic, anti-tumor and anti-helminthic. The main objectives of this research were to determine bioactive compounds in agarwood leaves; leaves extract and oil yield obtained from maceration and soxhlet extraction methods respectively. The maceration process was performed at different operating temperature of 25°C, 50°C and 75°C and different retention time at 30, 60, 90 and 120 minutes. Meanwhile, various solvents were used to extract the oil from agarwood leaves using soxhlet method which are hexane, water, isopropanol and ethanol. The extracted oil from agarwood leaves by soxhlet extraction was analyzed using gas chromatography mass spectrometry. The results showed that the highest extract of 1.53% was obtained when increase the temperature to 75 °C and longest retention time of 120 minutes gave the highest oil yield of 2.10 % by using maceration. This is because at higher temperature enhances the solubility solute and diffusivity coefficient, thus increase the extract yield while longer retention time allow the reaction between solvent and solute occurred more rapidly giving higher extract. Furthermore, the soxhlet extraction using n-hexane as the solvent gave the highest oil yield as compared to other solvent due to the non-polar properties of n-hexane increase the efficiency of oil which is also non-polar to soluble in the solvent. In addition, the results also reported that the oil extracted from agarwood leaves contains bioactive compounds which are phytol, squalene, n-hexadecanoic acid and

  20. Treatment for burn blisters: debride or leave intact?

    PubMed

    Murphy, Faye; Amblum, Jeshi

    2014-05-01

    This article presents findings from a systematic literature review of whether blisters arising from minor burns should be de-roofed or left intact. It discusses the risks of infection, healing outcomes, discomfort, choice of dressings and costs associated with each method, and reveals that debriding blisters larger than the patient's little fingernail while leaving smaller ones intact is generally agreed to be the best option. The article also explains external factors that influence the choice of whether to debride or leave blisters intact, reviews policy at the trust where one of the authors works in the context of the research and makes recommendations for practice.

  1. Family and Medical Leave Act; Definition of Spouse. Final rule.

    PubMed

    2016-04-08

    The U.S. Office of Personnel Management (OPM) is revising the definition of spouse in its regulations on the Family and Medical Leave Act (FMLA) as a result of the decision by the United States Supreme Court holding section 3 of the Defense of Marriage Act (DOMA) unconstitutional. The new definition replaces the existing definition, which contains language from DOMA that refers to "a legal union between one man and one woman.'' The new definition permits Federal employees with same-sex spouses to use FMLA leave in the same manner as Federal employees with opposite-sex spouses.

  2. The effects of California's paid family leave program on mothers' leave-taking and subsequent labor market outcomes.

    PubMed

    Rossin-Slater, Maya; Ruhm, Christopher J; Waldfogel, Jane

    2013-01-01

    This analysis uses March Current Population Survey data from 1999 to 2010 and a differences-in-differences approach to examine how California's first in the nation paid family leave (PFL) program affected leave-taking by mothers following childbirth, as well as subsequent labor market outcomes. We obtain robust evidence that the California program doubled the overall use of maternity leave, increasing it from an average of three to six weeks for new mothers--with some evidence of particularly large growth for less advantaged groups. We also provide evidence that PFL increased the usual weekly work hours of employed mothers of 1- to 3-year-old children by 10 to 17 percent and that their wage incomes may have risen by a similar amount.

  3. The Effects of California’s Paid Family Leave Program on Mothers’ Leave-Taking and Subsequent Labor Market Outcomes

    PubMed Central

    Rossin-Slater, Maya; Ruhm, Christopher; Waldfogel, Jane

    2013-01-01

    This analysis uses March Current Population Survey data from 1999–2010 and a differences-in-differences approach to examine how California’s first in the nation paid family leave (PFL) program affected leave-taking by mothers following childbirth, as well as subsequent labor market outcomes. We obtain robust evidence that the California program doubled the overall use of maternity leave, increasing it from an average of three to six weeks for new mothers – with some evidence of particularly large growth for less advantaged groups. We also provide evidence that PFL increased the usual weekly work hours of employed mothers of one-to-three year-old children by 10 to 17% and that their wage incomes may have risen by a similar amount. PMID:23547324

  4. Effects of organic extracts of six Bangladeshi plants on in vitro thrombolysis and cytotoxicity

    PubMed Central

    2013-01-01

    Background Thrombus formed in blood vessels lead to atherothrombotic diseases such as myocardial or cerebral infarction. Thrombolytic agents are used to dissolve the already formed clots in the blood vessels; however, these drugs sometimes cause serious and fatal consequences. Herbal preparations have been used since ancient times for the treatment of several diseases although they show little toxicity in some cases. Aqueous extracts of herbs used in thrombolysis have been reported before with cytotoxic data, however, the organic extracts of herbs have not been documented. This study aims to investigate whether organic extracts possess thrombolytic properties with minimal or no toxicity. Methods An in vitro thrombolytic model was used to check the clot lysis effect of six Bangladeshi herbal extracts viz., Ageratum conyzoides L., Clausena suffruticosa, Leea indica (Burm.f.) Merr., Leucas aspera Willd., Senna sophera L. Roxb., and Solanum torvum Swartz. using streptokinase as a positive control and water as a negative control. Briefly, venous blood drawn from twenty healthy volunteers was allowed to form clots which were weighed and treated with the test plant materials to disrupt the clots. Weight of clot after and before treatment provided a percentage of clot lysis. Cytotoxicity was screened by brine shrimp lethality bioassay using vincristine sulfate as positive control. Results Using an in vitro thrombolytic model, Ageratum conyzoides, Clausena suffruticosa, Leea indica, Leucas aspera, Senna sophera and Solanum torvum showed 18.12 ± 2.34%, 48.9 ± 2.44%, 39.30 ± 0.96%, 37.32 ± 2.00%, 31.61 ± 2.97% and 31.51 ± 0.57% and clot lysis respectively. Among the herbs studied Clausena suffruticosa, Leea indica and Leucas aspera showed very significant (p < 0.0001) percentage (%) of clot lysis compared to reference drug streptokinase (75.00 ± 3.04%). In brine shrimp cytotoxic assay, the extracts Ageratum conyzoides, Clausena suffruticosa, Leea indica, Leucas aspera

  5. Rapid and Pervasive Occupation of Fallen Mangrove Leaves by a Marine Zoosporic Fungus †

    PubMed Central

    Newell, S. Y.; Miller, J. D.; Fell, J. W.

    1987-01-01

    Samples of leaves of red mangrove (Rhizophora mangle) were incubated on an agar medium selective for pythiaceous oomycetes. Leaves on trees above the water did not contain oomycetes. Marine oomycetes, principally Phytophthora vesicula, had colonized leaves within 2 h of leaf submergence, probably finding them by chemotaxis. The frequency of occurrence of P. vesicula in submerged leaves reached 100% within 30 h of submergence. By 43 h most, if not all, parts of leaves were occupied, and surface treatment with a biocide indicated that leaves were occupied internally. Frequencies of P. vesicula remained near 100% through about 2 weeks of submergence and then declined to about 60% in older (≥4 weeks) leaves. Leaves of white mangrove (Laguncularia racemosa) were also extensively occupied by P. vesicula after falling into the water column, but decaying leaves of turtlegrass (Thalassia testudinum) were not colonized by oomycetes. Ergosterol analysis indicated that the standing crop of living, non-oomycete (ergosterol-containing) fungal mass in submerged red-mangrove leaves did not rise above that which had been present in senescent leaves on the tree; decaying turtlegrass leaves had an ergosterol content that was only about 2% of the maximum concentration detected for red-mangrove leaves. These results suggest that oomycetes are the predominant mycelial eucaryotic saprotrophs of mangrove leaves that fall into the water column and that for turtlegrass leaves which live, die, and decompose under submerged conditions, mycelial eucaryotes make no substantial contribution to decomposition. PMID:16347463

  6. Chromatographic Profiles of Ginkgo biloba Leaves and Selected Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ginkgo biloba leaves and their extracts are one of the most widely used herbal products or dietary supplements in the world. Their flavonoids and terpene lactones are considered to be the main beneficial components. Many previous studies have focused on specific components, or families of component...

  7. Why Some Students Leave College during Their Senior Year

    ERIC Educational Resources Information Center

    Hunt, Patricia F.; Boyd, Vivian S.; Gast, Linda K.; Mitchell, Alice; Wilson, Wendy

    2012-01-01

    Although many studies have examined college student attrition, no extant literature examines the phenomenon of undergraduates who discontinue their enrollment in college during a semester of their senior year. This study used both institutional and self-reported survey data to examine the rationale behind seniors' decision to leave college during…

  8. Using hyperspectral imaging technology to identify diseased tomato leaves

    NASA Astrophysics Data System (ADS)

    Li, Cuiling; Wang, Xiu; Zhao, Xueguan; Meng, Zhijun; Zou, Wei

    2016-11-01

    In the process of tomato plants growth, due to the effect of plants genetic factors, poor environment factors, or disoperation of parasites, there will generate a series of unusual symptoms on tomato plants from physiology, organization structure and external form, as a result, they cannot grow normally, and further to influence the tomato yield and economic benefits. Hyperspectral image usually has high spectral resolution, not only contains spectral information, but also contains the image information, so this study adopted hyperspectral imaging technology to identify diseased tomato leaves, and developed a simple hyperspectral imaging system, including a halogen lamp light source unit, a hyperspectral image acquisition unit and a data processing unit. Spectrometer detection wavelength ranged from 400nm to 1000nm. After hyperspectral images of tomato leaves being captured, it was needed to calibrate hyperspectral images. This research used spectrum angle matching method and spectral red edge parameters discriminant method respectively to identify diseased tomato leaves. Using spectral red edge parameters discriminant method produced higher recognition accuracy, the accuracy was higher than 90%. Research results have shown that using hyperspectral imaging technology to identify diseased tomato leaves is feasible, and provides the discriminant basis for subsequent disease control of tomato plants.

  9. 29 CFR 825.200 - Amount of leave.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... spouse, son, daughter, or parent is a military member on covered active duty status (or has been notified of an impending call or order to covered active duty). (b) An employer is permitted to choose any one... any FMLA leave as described in paragraph (a). (c) Under methods in paragraphs (b)(1) and (b)(2)...

  10. New cytotoxic steroids from the leaves of Clerodendrum trichotomum.

    PubMed

    Xu, Rui-Lan; Wang, Rui; Ding, Lan; Shi, Yan-Ping

    2013-07-01

    A phytochemical investigation of the leaves of Clerodendrum trichotomum led to the isolation of five new (2-6) and two known (1 and 7) steroids, whose structures and relative configurations were elucidated by comprehensive spectroscopic analysis and by comparison of their NMR data with those of related compounds. Steroids 2 and 5 exhibited moderate cytotoxicity in vitro against HeLa cell line.

  11. Isolation and Characterization of Phosphatidyl Choline from Spinach Leaves.

    ERIC Educational Resources Information Center

    Devor, Kenneth A.

    1979-01-01

    This inexpensive but informative experiment for undergraduate biochemistry students involves isolating phosphatidyl choline from spinach leaves. Emphasis is on introducing students to techniques of lipid extraction, separation of lipids, identification using thin layer chromatography, and identification of fatty acids. Three periods of three hours…

  12. Two new sphingolipids from the leaves of Piper betle L.

    PubMed

    Chen, Duo-Zhi; Xiong, Hua-Bin; Tian, Kai; Guo, Jun-Ming; Huang, Xiang-Zhong; Jiang, Zhi-Yong

    2013-09-12

    Two new sphingolipids, pipercerebrosides A (1) and B (2), were isolated from the leaves of Piper betle L. Their structures, including absolute configurations, were determined by spectroscopic analysis and chemical degradation. These two compounds did not show significant cytotoxic activity against the cancer cell lines K562 and HL-60 in a MTT assay.

  13. Maintenance Carbon Cycle in Crassulacean Acid Metabolism Plant Leaves 1

    PubMed Central

    Kenyon, William H.; Severson, Ray F.; Black, Clanton C.

    1985-01-01

    The reciprocal relationship between diurnal changes in organic acid and storage carbohydrate was examined in the leaves of three Crassulacean acid metabolism plants. It was found that depletion of leaf hexoses at night was sufficient to account quantitatively for increase in malate in Ananas comosus but not in Sedum telephium or Kalanchoë daigremontiana. Fructose and to a lesser extent glucose underwent the largest changes. Glucose levels in S. telephium leaves oscillated diurnally but were not reciprocally related to malate fluctuations. Analysis of isolated protoplasts and vacuoles from leaves of A. comosus and S. telephium revealed that vacuoles contain a large percentage (>50%) of the protoplast glucose, fructose and malate, citrate, isocitrate, ascorbate and succinate. Sucrose, a major constituent of intact leaves, was not detectable or was at extremely low levels in protoplasts and vacuoles from both plants. In isolated vacuoles from both A. comosus and S. telephium, hexose levels decreased at night at the same time malate increased. Only in A. comosus, however, could hexose metabolism account for a significant amount of the nocturnal increase in malate. We conclude that, in A. comosus, soluble sugars are part of the daily maintenance carbon cycle and that the vacuole plays a dynamic role in the diurnal carbon assimilation cycle of this Crassulacean acid metabolism plant. PMID:16664005

  14. [Thermal dissipation pathway in cucumber seedling leaves under hypoxia stress].

    PubMed

    Jia, Yong-xi; Sun, Jin; Wang, Li-ping; Shu, Sheng; Guo, Shi-rong

    2011-03-01

    A water culture experiment was conducted to study the relationship between photosynthetic thermal dissipation and xanthophyll cycle in cucumber seedling leaves under hypoxia stress (the dissolved oxygen concentration in nutrient solution was 0.9-1.1 mg x L(-1)). Under the hypoxia stress, there was a significant decrease in the quantum yield of PS II photochemistry rate (phi(PS II)), net photosynthetic rate (Pn) under saturation light intensity, quanta yield (AQY), and maximal photochemical efficiency (Fv/Fm), suggesting that the photoinhibition of the seedling leaves was induced. Meanwhile, the thermal dissipation (NPQ) and the allocation of dissipation energy (D) by antenna increased, but the photochemical quenching apparent (q(p)) decreased, suggesting the enhancement of thermal dissipation in cucumber leaves under hypoxia stress. A positive correlation was observed between NPQ and xanthophyll de-epoxidation state (DEPS), and both of them were promoted by ascorbic acid (AsA) and inhibited by 1,4-dithiothreitol (DTT), suggesting that xanthophyll cycle was the major pathway of photosynthetic thermal dissipation in cucumber seedling leaves under hypoxia stress.

  15. The evolution, morphology, and development of fern leaves

    PubMed Central

    Vasco, Alejandra; Moran, Robbin C.; Ambrose, Barbara A.

    2013-01-01

    Leaves are lateral determinate structures formed in a predictable sequence (phyllotaxy) on the flanks of an indeterminate shoot apical meristem. The origin and evolution of leaves in vascular plants has been widely debated. Being the main conspicuous organ of nearly all vascular plants and often easy to recognize as such, it seems surprising that leaves have had multiple origins. For decades, morphologists, anatomists, paleobotanists, and systematists have contributed data to this debate. More recently, molecular genetic studies have provided insight into leaf evolution and development mainly within angiosperms and, to a lesser extent, lycophytes. There has been recent interest in extending leaf evolutionary developmental studies to other species and lineages, particularly in lycophytes and ferns. Therefore, a review of fern leaf morphology, evolution and development is timely. Here we discuss the theories of leaf evolution in ferns, morphology, and diversity of fern leaves, and experimental results of fern leaf development. We summarize what is known about the molecular genetics of fern leaf development and what future studies might tell us about the evolution of fern leaf development. PMID:24027574

  16. Caregiver Leave-Taking in Spain: Rate, Motivations, and Barriers.

    PubMed

    Rogero-García, Jesús; García-Sainz, Cristina

    2016-01-01

    This paper aims to (1) determine the rate of (full- and part-time) caregiver leave-taking in Spain, (2) identify the reasons conducive to a more intense use of this resource, and (3) ascertain the main obstacles to its use, as perceived by caregivers. All 896 people covered by the sample were engaging in paid work and had cared for dependent adults in the last 12 years. This resource, in particular the full-time alternative, was found to be a minority option. The data showed that legal, work-related, and family and gender norm issues are the four types of factors that determine the decision to take such leaves. The most significant obstacles to their use are the forfeiture of income and the risk of losing one's job. Our results suggest that income replacement during a leave would increase the take-up of these resources. Moreover, enlargement of public care services would promote the use of leave as a free choice of caregivers.

  17. Why Do Student Nurses Leave? Suggestions from a Delphi Study.

    ERIC Educational Resources Information Center

    Last, Lynn; Fulbrook, Paul

    2003-01-01

    Focus groups and interviews gathered professional opinions about why students leave nursing; results were formulated into a questionnaire administered to 32 students in a three-round Delphi. Factors contributing to attrition included theory-practice gap, university-clinical site relationships, unmet expectations, stress, and not feeling valued.…

  18. Antecedents and Consequences of Early School Leaving. I. Introduction

    ERIC Educational Resources Information Center

    Educational Documentation and Information, 1972

    1972-01-01

    Developing nations have placed high priorities on budgeting for education expenditures so reflect concern over early school leaving and its consequences to their economy. An analysis can give a basis for assessing the relevance or effectiveness of a school system. Here the purpose, scope, previous surveys, sources, organization, and terms are…

  19. 50. STARBOARD VIEW LEAVING HOMEPORT IN MEMPHIS TO TRAVEL TO ...

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

    50. STARBOARD VIEW LEAVING HOMEPORT IN MEMPHIS TO TRAVEL TO CURTIS BAY, MARYLAND. PRIOR TO CONVERSION TO NEW HOISTING SYSTEM, 1962. - U.S. Coast Guard Cutter WHITE PINE, U.S. Coast Guard 8th District Base, South Broad Street, Mobile, Mobile County, AL

  20. Faculty Sabbatical Leaves: Evidence from NSOPF, 1999 and 2004

    ERIC Educational Resources Information Center

    Mamiseishvili, Ketevan; Miller, Michael T.

    2010-01-01

    In the context of increased expectations for accountability and growing controversy surrounding sabbatical leave programs, it is important to address seemingly simple questions of who is or should be awarded a sabbatical and what the rationale is for the award. The study attempted to offer some insight on these issues by examining the factors that…

  1. Three new hecogenin glycosides from fermented leaves of Agave americana.

    PubMed

    Jin, Jian-Ming; Liu, Xi-Kui; Yang, Chong-Ren

    2003-06-01

    Eight steroidal compounds, including three new hecogenin glycosides, agamenosides D-F, were isolated from the fermented leaves of Agave americana. The structures of the new steroidal saponins were elucidated by spectroscopic data and chemical methods. The activity of the isolated compounds on deformations of mycelia germinated from conidia of Pyricularia oaryzae P-2b was evaluated.

  2. Triterpenoid glycosides from the leaves of Meliosma henryi.

    PubMed

    Alabdul Magid, Abdulmagid; Morjani, Hamid; Harakat, Dominique; Madoulet, Claudie; Dumontet, Vincent; Lavaud, Catherine

    2015-01-01

    Seven triterpenoid glycosides, named meliosmosides A-G, were isolated from the leaves of Meliosma henryi Diels (Sabiaceae). Their structures were elucidated by different spectroscopic methods including 1D and 2D NMR experiments as well as HRESIMS analysis. Isolated compounds were evaluated for their cytotoxic activity against KB cell line.

  3. Leaving College: Rethinking the Causes and Cures of Student Attrition.

    ERIC Educational Resources Information Center

    Tinto, Vincent

    The dimensions and consequences of college student attrition and features of institutional action to deal with attrition are discussed. Patterns of student departure from individual colleges as opposed to permanent college withdrawal are addressed. After synthesizing the research on multiple causes of student leaving, a theory of student departure…

  4. Syncom IV-1 satellite leaving Discovery's payload bay

    NASA Technical Reports Server (NTRS)

    1984-01-01

    In a frisbee-type method, the Syncom IV-1 satellite leaves the Discovery's payload bay on its way into service for the U.S. Navy. Retrieval hardware and part of the pallet for securing the Palapa B-2 are pictured near the protective shield for the now vacated Telest-H/PAM-B.

  5. Cytology of infection of apple leaves by Diplocarpon mali

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diplocarpon mali, the causal agent of Marssonina leaf blotch of apple, causes severe defoliation during the growing season. Little information is available on the mode of infection and infection process. In this study, the infection strategies of D. mali in apple leaves were investigated using fluor...

  6. "Who Leaves?" Teacher Attrition and Student Achievement. Working Paper 23

    ERIC Educational Resources Information Center

    Boyd, Donald; Grossman, Pamela; Lankford, Hamilton; Loeb, Susanna; Wyckoff, James

    2009-01-01

    This paper analyzes attrition patterns among teachers in New York City public elementary and middle schools and explores whether teachers who transfer among schools, or leave teaching entirely, are more or less effective than those who remain. We find that the first-year teachers who are less effective in improving student math scores have higher…

  7. LEAVES AS INDICATORS OF EXPOSURE TO AIRBORNE VOLATILE ORGANIC COMPOUNDS

    EPA Science Inventory

    The concentration of volatile organic compounds (VOCs) in leaves is primarily a product of airborne exposures and dependent upon bioconcentration factors and release rates. The bioconcentration factors for VOCs in grass are found to be related to their partitioning between octan...

  8. Einstein's Tea Leaves and Pressure Systems in the Atmosphere

    ERIC Educational Resources Information Center

    Tandon, Amit; Marshall, John

    2010-01-01

    Tea leaves gather in the center of the cup when the tea is stirred. In 1926 Einstein explained the phenomenon in terms of a secondary, rim-to-center circulation caused by the fluid rubbing against the bottom of the cup. This explanation can be connected to air movement in atmospheric pressure systems to explore, for example, why low-pressure…

  9. The reconfiguration of broad leaves in strong winds and currents

    NASA Astrophysics Data System (ADS)

    Miller, Laura; Hoover, Alex; Marzuola, Jeremy

    2015-11-01

    Flexible plants, fungi, and sessile animals are thought to reconfigure in the wind and water to reduce the drag forces that act upon them. In strong winds, for example, leaves roll up into cone shapes that reduce flutter and drag when compared to paper cut-outs with similar shape and flexibility. Simple mathematical models of a flexible beam immersed in a two-dimensional flow will also exhibit this behavior. What is less understood is how the mechanical properties of a two-dimensional leaf in a three-dimensional flow will passively allow roll up and reduce drag and flutter. In this project, we use computational fluid dynamics and particle image velocimetry to determine how leaves roll up into drag reducing shapes in extreme conditions. Force and flow measurements are taken on real broad leaves and simplified physical models. Corresponding numerical simulations using the immersed boundary method are used to understand which features of the flexible leaves result in proper reconfiguration and drag reduction.

  10. Organizational Ethics and Teachers' Intent to Leave: An Integrative Approach

    ERIC Educational Resources Information Center

    Shapira-Lishchinsky, Orly; Rosenblatt, Zehava

    2009-01-01

    Purpose: The present study focuses on developing a conceptual framework that explores the relationships between teachers' intent to leave and a spectrum of ethics perceptions. The authors argue that these relationships are mediated by organizational commitment (affective and normative). Research Design: Organizational ethics was measured by…

  11. Chromatographic profiles of Ginkgo biloba leaves and selected products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An LC-DAD-ESI/MS method was developed to obtain chromatographic profiles for the flavonoids and terpene lactones of Ginkgo biloba leaves and selected G. biloba products. The method was used to identify 46 glycosylated flavonols and flavones, 3 free flavonol aglycones, catechin, 10 biflavones, a dihy...

  12. 29 CFR 825.301 - Designation of FMLA leave.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee and Employer Rights and Obligations Under the Act § 825.301... the Act or even mention the FMLA to meet his or her obligation to provide notice, though the...

  13. Dengue fever treatment with Carica papaya leaves extracts

    PubMed Central

    Ahmad, Nisar; Fazal, Hina; Ayaz, Muhammad; Abbasi, Bilal Haider; Mohammad, Ijaz; Fazal, Lubna

    2011-01-01

    The main objective of the current study is to investigate the potential of Carica papaya leaves extracts against Dengue fever in 45 year old patient bitten by carrier mosquitoes. For the treatment of Dengue fever the extract was prepared in water. 25 mL of aqueous extract of C. papaya leaves was administered to patient infected with Dengue fever twice daily i.e. morning and evening for five consecutive days. Before the extract administration the blood samples from patient were analyzed. Platelets count (PLT), White Blood Cells (WBC) and Neutrophils (NEUT) decreased from 176×103/µL, 8.10×103/µL, 84.0% to 55×103/µL, 3.7×103/µL and 46.0%. Subsequently, the blood samples were rechecked after the administration of leaves extract. It was observed that the PLT count increased from 55×103/µL to 168×103/µL, WBC from 3.7×103/µL to 7.7×103/µL and NEUT from 46.0% to 78.3%. From the patient feelings and blood reports it showed that Carica papaya leaves aqueous extract exhibited potential activity against Dengue fever. Furthermore, the different parts of this valuable specie can be further used as a strong natural candidate against viral diseases. PMID:23569787

  14. Physical Education, Liberal Education and the Leaving Certificate Examination

    ERIC Educational Resources Information Center

    Mulcahy, D. G.

    2012-01-01

    This article considers the conceptualization of physical education as a Leaving Certificate Examination subject and the place of physical education in a liberal education. Special attention is given to the conceptual evolution of physical education and its intrinsic educational values and to the developments in the idea of a liberal education over…

  15. "Hello, Goodbye": Exploring the Phenomenon of Leaving Teaching Early

    ERIC Educational Resources Information Center

    Torres, Aubrey Scheopner

    2012-01-01

    High teacher attrition rates hinder schools in their ability to provide quality instruction. This study seeks to understand why teachers leave early in their careers (within the first 5 years) using a mixed methods approach that combined 50 in-depth interviews with 15 public and 10 Catholic school teachers in the United States who left early with…

  16. Is Your Sick Leave Bank in Good Health?

    ERIC Educational Resources Information Center

    Hoover, James P.

    2012-01-01

    Sick leave banks are a common staple of teacher contracts. Although these banks may benefit employees, they expose school districts to a variety of complications and unintended consequences, including administrative complexity, potential cash flow implications, cost disparities, increased absenteeism, instructional instability, privacy issues, and…

  17. Factors Related to Teachers' Intention to Leave the Classroom Early

    ERIC Educational Resources Information Center

    Tippens, Abby; Ricketts, John C.; Morgan, A. Christian; Navarro, Marie; Flanders, Frank B.

    2013-01-01

    The challenge of retaining teachers in the profession of agricultural education is a prevalent and growing problem in the United States. The purpose of this study was to determine the primary factors contributing to intention to leave the profession among Georgia agriculture teachers. Teacher-participants responded to a web-based survey which…

  18. 77 FR 8959 - The Family and Medical Leave Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ... spouse, parent, son, or daughter with a serious health condition; or when the employee is unable to work due to the employee's own serious health condition. The FMLA was amended in January 2008 by enactment... protected family and medical leave, employers must also maintain any preexisting group health plan...

  19. Antioxidant Potential and Oil Composition of Callistemon viminalis Leaves

    PubMed Central

    Zubair, Muhammad; Hassan, Sadia; Rizwan, Komal; Rasool, Nasir; Riaz, Muhammad; Zia-Ul-Haq, M.; De Feo, Vincenzo

    2013-01-01

    The present study was designed to investigate the antioxidant potential and oil composition of Callistemon viminalis leaves. GC-MS analysis of the n-hexane extract revealed the presence of 40 compounds. Leaves contained appreciable levels of total phenolic contents (0.27–0.85 GAE mg/g) and total flavonoid contents (2.25–7.96 CE mg/g). DPPH radical scavenging IC50 and % inhibition of linoleic acid peroxidation were found to be in the ranges of 28.4–56.2 μg/ml and 40.1–70.2%, respectively. The haemolytic effect of the plant leaves was found in the range of 1.79–4.95%. The antioxidant activity of extracts was also studied using sunflower oil as an oxidative substrate and found that it stabilized the oil. The correlation between the results of different antioxidant assays and oxidation parameters of oil indicated that leaves' methanolic extract, exhibiting higher TPC and TFC and scavenging power, was also more potent for enhancing the oxidative stability of sunflower oil. PMID:23818824

  20. McCallen Professional Research and Teaching Leave Report

    SciTech Connect

    McCallen, R.

    2015-10-16

    This end of assignment report for a Professional Research and Teaching (PRT) Leave award includes the attached assessment of success by the host organization, University of California Davis (UCD). The following summarizes the accomplishments and attached are a selection of documented items.

  1. Photosynthesis in Plants with Non-Green Leaves

    ERIC Educational Resources Information Center

    Vartak, Rehka

    2006-01-01

    Enquiry based learning is an important tool in science teaching. Students of Class XI (16-17 years old) were asked to hypothesise on the role of different pigments found in plants with non-green leaves. The majority hypothesised that these plants were devoid of chlorophylls and some other pigments performed the function of photosynthesis. Their…

  2. Spectral characteristics of normal and nutrient-deficient maize leaves

    NASA Technical Reports Server (NTRS)

    Al-Abbas, A. H.; Barr, R.; Hall, J. D.; Crane, F. L.; Baumgardner, M. F.

    1972-01-01

    Reflectance, transmittance and absorbance spectra of normal and six types of mineral-deficient (N,P,K,S,Mg and Ca) maize (Zea mays L.) leaves were analyzed at 30 selected wavelengths along the electromagnetic spectrum from 500 to 2600 nm. Chlorophyll content and percent leaf moisture were also determined. Leaf thermograms were obtained for normal, N- and S- deficient leaves. The results of the analysis of variance showed significant differences in reflectance, transmittance and absorbance in the visible wavelengths among leaf numbers 3, 4, and 5, among the seven nutrient treatments, and among the interactions of leaves and treatments. In the reflective infrared wavelengths only treatments produced significant differences. The chlorophyll content of leaves was reduced in all deficiencies in comparison to controls. Percent moisture was increased in S-, Mg- and N- deficiencies. Positive correlation (r = 0.707) between moisture content and percent absorption at both 1450 and 1930 nm were obtained. Polynomial regression analysis of leaf thickness and leaf moisture content showed that these two variables were significantly and directly related (r = 0.894).

  3. When the Leader Leaves: Sustaining Success at Romero High School

    ERIC Educational Resources Information Center

    Johnson, Lauri; Sillman, Kathryn

    2012-01-01

    This case study asks readers to consider what leadership actions might help to sustain success for immigrant students in a small urban high school when the leader leaves. Principal Michael Perez, the founding principal of Romero High School, has been recruited to become the superintendent of a first-ring suburban district with rapidly changing…

  4. Students Matter in School Reform: Leaving Fingerprints and Becoming Leaders

    ERIC Educational Resources Information Center

    Osberg, Jerusha; Pope, Denise; Galloway, Mollie

    2006-01-01

    Our examination of three schools demonstrates how students can be involved in school reform by giving input about problems, helping design the reform, and sharing implementation responsibilities with adult leaders. Their involvement affects both the reform--as students leave their fingerprints on it--and the students themselves, who show signs of…

  5. Physiological responses of plant leaves to atmospheric ammonia and ammonium

    NASA Astrophysics Data System (ADS)

    Pearson, J.; Soares, A.

    Misting of leaves of several plant species with 3 mM aqueous NH +4 at pH 5, or fumigation with 3000 μg m -3 gaseous NH 3 for 1 h, elicits similar biochemical and physiological changes in the species tested. The enzyme glutamine synthetase (GS) was shown to increase its activity in all species, while that of nitrate reductase (NR) was inhibited, at least in those species which possessed the ability to induce foliar NR. At the same time there were marked changes in organic anion concentrations, with malate and citrate in particular being reduced in concentration, following either NH +4 or NH 3 application to leaves. The changes in organic anions are also discussed in the light of pH regulation by the cell. A stimulation of photosynthesis was also evident when leaves were treated with either NH 3 or NH +4. It is argued that, because of the differences in solution chemistry of the two ammonia forms, the aqueous form applied at pH 5 and the gaseous form being an alkali in solution, these changes can only have occurred through the ability of the leaves to readily assimilate both forms of the ammonia. The biochemical changes might have potential as markers for the onset of physiological perturbation by atmospheric ammonia pollution, particularly changes in organic acid concentration; their use in an index of pollution stress is briefly discussed.

  6. In vitro antiprotozoal activity of the leaves of Artemisia ludoviciana.

    PubMed

    Said Fernández, Salvador; Ramos Guerra, Monica Celina; Mata Cárdenas, Benito David; Vargas Villarreal, Javier; Villarreal Treviño, Licet

    2005-07-01

    The inhabitants of Northeast of Mexico use an infusion of leaves from Artemisia ludoviciana as an antidiarrheal remedy. The aqueous, methanol, acetone and hexane leaf extracts from mature plants were found to be active in vitro against the parasitic protozoa Entamoeba histolytica and Giardia lamblia.

  7. 5 CFR 630.401 - Granting sick leave.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... section, an agency must grant sick leave to an employee when he or she— (1) Receives medical, dental, or..., dental, or optical examination or treatment; or (ii) Provides care for a family member with a serious... section must be recalculated based on the new tour of duty. (f) An agency may advance a maximum of 30...

  8. 5 CFR 630.401 - Granting sick leave.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... section, an agency must grant sick leave to an employee when he or she— (1) Receives medical, dental, or..., dental, or optical examination or treatment; or (ii) Provides care for a family member with a serious... section must be recalculated based on the new tour of duty. (f) An agency may advance a maximum of 30...

  9. 25 CFR 38.12 - Leave system for education personnel.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... will request the use of this leave in advance when it is for personal use or personal business (e.g...-job and not covered by the Federal Employee's Compensation Act Regulations. Medical and dental appointments may be included under this part. However, whenever possible, medical and dental...

  10. 25 CFR 38.12 - Leave system for education personnel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... will request the use of this leave in advance when it is for personal use or personal business (e.g...-job and not covered by the Federal Employee's Compensation Act Regulations. Medical and dental appointments may be included under this part. However, whenever possible, medical and dental...

  11. Dengue fever treatment with Carica papaya leaves extracts.

    PubMed

    Ahmad, Nisar; Fazal, Hina; Ayaz, Muhammad; Abbasi, Bilal Haider; Mohammad, Ijaz; Fazal, Lubna

    2011-08-01

    The main objective of the current study is to investigate the potential of Carica papaya leaves extracts against Dengue fever in 45 year old patient bitten by carrier mosquitoes. For the treatment of Dengue fever the extract was prepared in water. 25 mL of aqueous extract of C. papaya leaves was administered to patient infected with Dengue fever twice daily i.e. morning and evening for five consecutive days. Before the extract administration the blood samples from patient were analyzed. Platelets count (PLT), White Blood Cells (WBC) and Neutrophils (NEUT) decreased from 176×10(3)/µL, 8.10×10(3)/µL, 84.0% to 55×10(3)/µL, 3.7×10(3)/µL and 46.0%. Subsequently, the blood samples were rechecked after the administration of leaves extract. It was observed that the PLT count increased from 55×10(3)/µL to 168×10(3)/µL, WBC from 3.7×10(3)/µL to 7.7×10(3)/µL and NEUT from 46.0% to 78.3%. From the patient feelings and blood reports it showed that Carica papaya leaves aqueous extract exhibited potential activity against Dengue fever. Furthermore, the different parts of this valuable specie can be further used as a strong natural candidate against viral diseases.

  12. Methyl carnosate, an antibacterial diterpene isolated from Salvia officinalis leaves.

    PubMed

    Climati, Elisa; Mastrogiovanni, Fabio; Valeri, Maria; Salvini, Laura; Bonechi, Claudia; Mamadalieva, Nilufar Zokirzhonovna; Egamberdieva, Dilfuza; Taddei, Anna Rita; Tiezzi, Antonio

    2013-04-01

    Ethanolic extracts of Salvia officinalis leaves demonstrated antibacterial activity against Bacillus cereus. Fractionation of the extracts led to the isolation of the most active antibacterial compound, which, from spectroscopic and LC-MS evidence, was proved to be the diterpene, methyl carnosate.

  13. Rapid isolation of intact chloroplasts from spinach leaves.

    PubMed

    Joly, David; Carpentier, Robert

    2011-01-01

    In this chapter, a rapid method to isolate intact chloroplasts from spinach leaves is described. Intact chloroplasts are isolated using two short centrifugation steps and avoiding the use of percoll gradient. Intactness of chloroplast is evaluated by the inability of potassium ferricyanide to enter inside the chloroplasts and to act as an electron acceptor for photosystem II.

  14. "Ya Me Fui" When English Learners Consider Leaving School

    ERIC Educational Resources Information Center

    Boone, Jeanmarie Hamilton

    2013-01-01

    This study examines narratives of English learners who have either dropped out or considered dropping out as a result of their experience in high school. This research seeks to determine at which point students left or considered leaving school, which often goes undetected in traditional quantitative data collection methods. The common themes that…

  15. High throughput sequencing of small RNAs in Potato Leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding the role of small RNAs (sRNAs) in gene regulation, function and development is a rapidly evolving field. sRNAs result from transcript degradation and to regulatory micro RNA (miRNA) and small inhibitory RNA (siRNA) classes involved in gene regulation. The sRNAs from potato leaves were...

  16. Efficiency of removal of cadmium from aqueous solutions by plant leaves and the effects of interaction of combinations of leaves on their removal efficiency.

    PubMed

    Salim, R; Al-Subu, M; Dawod, E

    2008-05-01

    Removal of cadmium from aqueous solutions using 20 species of plant leaves and combinations of these leaves have been studied. Several factors affecting the removal efficiency have been studied. The most efficient types of plant leaves for the removal of cadmium are those of styrax, plum, pomegranate and walnut. The interaction effect of the combined leaf samples on the efficiency of removal of cadmium has been found to be additive in combinations involving styrax plant leaves but seems to be antagonistic in all other combinations. The optimum experimental conditions for removal of cadmium have been found to be at pH 4.1, using high concentrations of naturally dried plant leaves, using ground leaves and to remove cadmium from agitated aqueous solutions. The percentage of metal removed at an initial cadmium concentration of 10mg/l by the most efficient types of leaves have been found to be 85% for styrax leaves, 85% for plum leaves, 80% for pomegranate leaves, 78% for walnut leaves and 77% for meddler leaves. The presence of foreign ions or complexing agents has been found to reduce the efficiency of removal of cadmium by plant leaves. About 80-85% of the cadmium in charged plant leaves has been released under the influence of changing the pH of the solution, addition of competing ions and the addition of EDTA. The results of removal of cadmium by plant leaves have been found to follow the Freundlich adsorption isotherm, first-order reaction with respect to cadmium and to have intra-pore diffusion as the rate-limiting step.

  17. Incidence of naturally internalized bacteria in lettuce leaves.

    PubMed

    Hou, Zhe; Fink, Ryan C; Radtke, Christie; Sadowsky, Michael J; Diez-Gonzalez, Francisco

    2013-04-01

    Lettuce is the fresh leafy vegetable most frequently involved in foodborne disease outbreaks. Human bacterial pathogens may be experimentally internalized into lettuce plants, but the occurrence of natural microflora inside lettuce leaves has not been elucidated. To characterize the endophytic microorganism residing in commercial lettuce leaves, two separate studies were conducted. First, a total of 30 and 25 heads of romaine and red leaf lettuce, respectively, served as the source of individual leaves which were surface sterilized, stomached, enriched in BHI broth for 24h and plated onto BHI agar for non-selective isolation of internalized microorganism. In a separate survey, 80 heads of each of the two types of lettuce were similarly processed, except that GN broth and MacConkey agar (MCA) were used for isolation of Gram negative bacteria. Thirty-eight out of 100 leaves were positive for internalized microorganisms, and Bacillus, Pseudomonas and Pantoea were the genera most frequently found in both types of lettuce. Members of the genus Erwinia were isolated from romaine lettuce only. In the second study, 21 and 60% of romaine and red leaf lettuce heads, respectively, had internalized bacteria capable of growing on MCA. Among the Gram negative strains, Pseudomonas and Pantoea genera were most frequently isolated. Enterobacter isolates were obtained from three red leaf samples. In summary, spore-forming bacteria and traditional epiphytic bacterial genera were frequently detected in surface-sterilized commercial lettuce leaves. Despite the common occurrence of internalized bacteria, only Enterobacter was related to Escherichia coli O157:H7 and Salmonella.

  18. Isolation of Mesophyll Cells from Sedum telephium Leaves 1

    PubMed Central

    Rouhani, I.; Vines, H. M.; Black, C. C.

    1973-01-01

    A technique is described for mechanically isolating metabolically active individual spongy mesophyll cells from the Crassulacean acid metabolism plant, Sedum telephium. Mature leaves are selected at about 2 PM when acidity is low, and three different media are used to reduce the problem of leaf acidity and to maintain isotonic conditions. The upper and lower epidermis is peeled from chilled leaves and the leaves are suspended in a buffered “soaking medium,” then gently ground with a mortar and pestle. Cells and debris are separated using a “washing medium,” with cells being filtered through a 136 micron net and collected on an 80 micron net. Cells then are suspended in a “cell suspension medium” and concentrated by centrifugation. Approximately 2 hours are required for the isolation procedure, and activity in CO2 fixation is constant for up to 4 hours after isolation. Microscopic examination shows about 65% of the isolated cells appear intact and unplasmolyzed and are similar to leaf msophyll cells. The yield of cells on a leaf chlorophyll basis is about 1%. A light micrograph of the isolated cells is given. The isolated cells upon addition of phosphoenolpyruvate, 2-phosphoglycerate, and ribulose-1, 5-diphosphate fix CO2 as rapidly as intact leaves; however, without exogenous substrate the cells only fix CO2 between 10 and 20% of intact leaves. The temperature and pH optima for cellular CO2 fixation in the presence of phosphoenolpyruvate is 35 to 45 C and 7.5 to 9.0, respectively. The light and dark portions of CO2 fixation with the isolated cells are considered in relation to a scheme for net CO2 fixation by Crassulacean acid metabolism plants. Images PMID:16658305

  19. Structure of fructans from excised leaves of New Zealand flax.

    PubMed

    Sims, I M; Cairns, A J; Furneaux, R H

    2001-07-01

    The accumulation of total water-soluble carbohydrate, and specifically sucrose and fructan, by excised leaves of Phormium tenax and P. cookianum (family Phormiaceae J. G. Agardh, order Asparagales) was investigated. Total water-soluble carbohydrate content of excised leaves of P. tenax and P. cookianum increased during 48 h of continuous illumination at an average rate of 1.3 and 0.9 mg g(-1) fresh weight leaf per hour, respectively. The sucrose content of excised leaves increased throughout the experimental period. The fructan content of excised leaves of P. tenax increased slightly throughout the experimental period, whilst that of P. cookianum was variable and showed no overall change. Chemical and spectroscopic analysis of the fructans obtained from the two Phormium species showed that they were similar to each other and contained mostly 1-linked and terminal fructofuranosyl (Fruf) residues, together with smaller amounts of 6-linked Fruf, 1,6-branched Fruf, terminal and 6-linked glucopyranosyl residues. Separation of the fructans by thin-layer and high-performance anion-exchange chromatography revealed the presence of a complex mixture of fructo-oligosaccharides and higher molecular weight fructan. The branched structure of the fructans isolated from excised leaves of Phormium resembles that of fructans and fructo-oligosaccharides isolated from some related species within the order Asparagales (Agave vera cruz, Cordyline australis and Urginea maritima), but is distinct from the linear structure of fructans from others (Allium cepa and Asparagus officinalis). The structural heterogeniety of fructans within both the order Asparagales and superorder Liliiflorae may be a useful chemotaxonomic aid.

  20. Tracking synthesis and turnover of triacylglycerol in leaves.

    PubMed

    Tjellström, Henrik; Strawsine, Merissa; Ohlrogge, John B

    2015-03-01

    Triacylglycerol (TAG), typically represents <1% of leaf glycerolipids but can accumulate under stress and other conditions or if leaves are supplied with fatty acids, or in plants transformed with regulators or enzymes of lipid metabolism. To better understand the metabolism of TAG in leaves, pulse-chase radiolabelling experiments were designed to probe its synthesis and turnover. When Arabidopsis leaves were incubated with [(14)C]lauric acid (12:0), a major initial product was [(14)C]TAG. Thus, despite low steady-state levels, leaves possess substantial TAG biosynthetic capacity. The contributions of diacylglycerol acyltransferase1 and phospholipid:diacylglycerol acyltransferase1 to leaf TAG synthesis were examined by labelling of dgat1 and pdat1 mutants. The dgat1 mutant displayed a major (76%) reduction in [(14)C]TAG accumulation whereas pdat1 TAG labelling was only slightly reduced. Thus, DGAT1 has a principal role in TAG biosynthesis in young leaves. During a 4h chase period, radioactivity in TAG declined 70%, whereas the turnover of [(14)C]acyl chains of phosphatidylcholine (PC) and other polar lipids was much lower. Sixty percent of [(14)C]12:0 was directly incorporated into glycerolipids without modification, whereas 40% was elongated and desaturated to 16:0 and 18:1 by plastids. The unmodified [(14)C]12:0 and the plastid products of [(14)C]12:0 metabolism entered different pathways. Although plastid-modified (14)C-labelled products accumulated in monogalactosyldiacylglycerol, PC, phosphatidylethanolamine, and diacylglcerol (DAG), there was almost no accumulation of [(14)C]16:0 and [(14)C]18:1 in TAG. Because DAG and acyl-CoA are direct precursors of TAG, the differential labelling of polar glycerolipids and TAG by [(14)C]12:0 and its plastid-modified products provides evidence for multiple subcellular pools of both acyl-CoA and DAG.

  1. Circular spectropolarimetric sensing of chiral photosystems in decaying leaves

    NASA Astrophysics Data System (ADS)

    Patty, C. H. Lucas; Visser, Luuk J. J.; Ariese, Freek; Buma, Wybren Jan; Sparks, William B.; van Spanning, Rob J. M.; Röling, Wilfred F. M.; Snik, Frans

    2017-03-01

    Circular polarization spectroscopy has proven to be an indispensable tool in photosynthesis research and (bio)molecular research in general. Oxygenic photosystems typically display an asymmetric Cotton effect around the chlorophyll absorbance maximum with a signal ≤ 1 % . In vegetation, these signals are the direct result of the chirality of the supramolecular aggregates. The circular polarization is thus directly influenced by the composition and architecture of the photosynthetic macrodomains, and is thereby linked to photosynthetic functioning. Although ordinarily measured only on a molecular level, we have developed a new spectropolarimetric instrument, TreePol, that allows for both laboratory and in-the-field measurements. Through spectral multiplexing, TreePol is capable of fast measurements with a sensitivity of ∼ 1 *10-4 and is therefore suitable of non-destructively probing the molecular architecture of whole plant leaves. We have measured the chiroptical evolution of Hedera helix leaves for a period of 22 days. Spectrally resolved circular polarization measurements (450-900 nm) on whole leaves in transmission exhibit a strong decrease in the polarization signal over time after plucking, which we accredit to the deterioration of chiral macro-aggregates. Chlorophyll a levels measured over the same period by means of UV-vis absorption and fluorescence spectroscopy showed a much smaller decrease. With these results we are able to distinguish healthy from deteriorating leaves. Hereby we indicate the potency of circular polarization spectroscopy on whole and intact leaves as a nondestructive tool for structural and plant stress assessment. Additionally, we underline the establishment of circular polarization signals as remotely accessible means of detecting the presence of extraterrestrial life.

  2. Tracking synthesis and turnover of triacylglycerol in leaves

    DOE PAGES

    Tjellstrom, Henrik; Strawsine, Merissa; Ohlrogge, John B.

    2015-01-21

    Triacylglycerol (TAG), typically represents <1% of leaf glycerolipids but can accumulate under stress and other conditions or if leaves are supplied with fatty acids, or in plants transformed with regulators or enzymes of lipid metabolism. To better understand the metabolism of TAG in leaves, pulse-chase radiolabelling experiments were designed to probe its synthesis and turnover. When Arabidopsis leaves were incubated with [14C]lauric acid (12:0), a major initial product was [14C]TAG. Thus, despite low steady-state levels, leaves possess substantial TAG biosynthetic capacity. The contributions of diacylglycerol acyltransferase1 and phospholipid:diacylglycerol acyltransferase1 to leaf TAG synthesis were examined by labelling of dgat1 andmore » pdat1 mutants. The dgat1 mutant displayed a major (76%) reduction in [14C]TAG accumulation whereas pdat1 TAG labelling was only slightly reduced. Thus, DGAT1 has a principal role in TAG biosynthesis in young leaves. During a 4h chase period, radioactivity in TAG declined 70%, whereas the turnover of [14C]acyl chains of phosphatidylcholine (PC) and other polar lipids was much lower. Sixty percent of [14C]12:0 was directly incorporated into glycerolipids without modification, whereas 40% was elongated and desaturated to 16:0 and 18:1 by plastids. The unmodified [14C]12:0 and the plastid products of [14C]12:0 metabolism entered different pathways. Although plastid-modified 14C-labelled products accumulated in monogalactosyldiacylglycerol, PC, phosphatidylethanolamine, and diacylglcerol (DAG), there was almost no accumulation of [14C]16:0 and [14C]18:1 in TAG. Lastly, because DAG and acyl-CoA are direct precursors of TAG, the differential labelling of polar glycerolipids and TAG by [14C]12:0 and its plastid-modified products provides evidence for multiple subcellular pools of both acyl-CoA and DAG.« less

  3. Potential of essential oils for protection of grains contaminated by aflatoxin produced by Aspergillus flavus

    PubMed Central

    Esper, Renata H.; Gonçalez, Edlayne; Marques, Marcia O. M.; Felicio, Roberto C.; Felicio, Joana D.

    2014-01-01

    Aflatoxin B1 (AFB1) is a highly toxic and carcinogenic metabolite produced by Aspergillus species on food and agricultural commodities. Inhibitory effects of essential oils of Ageratum conyzoides (mentrasto) and Origanum vulgare (oregano) on the mycelial growth and aflatoxin B1 production by Aspergillus flavus have been studied previously in culture medium. The aim of this study was to evaluate aflatoxin B1 production by Aspergillus flavus in real food systems (corn and soybean) treated with Ageratum conyzoides (mentrasto) and Origanum vulgare (oregano) essential oils. Samples with 60 g of the grains were treated with different volumes of essential oils, 200, 100, 50, and 10 μL for oregano and 50, 30, 15, and 10 μL for mentrasto. Fungal growth was evaluated by disk diffusion method. Aflatoxin B1 production was evaluated inoculating suspensions of A. flavus containing 1.3 × 105 spores/mL in 60 g of grains (corn and soybeans) after adjusting the water activity at 0.94. Aflatoxin was quantified by photodensitometry. Fungal growth and aflatoxin production were inhibited by essential oils, but the mentrasto oil was more effective in soybeans than that of oregano. On the other hand, in corn samples, the oregano essential oil was more effective than that of mentrasto. Chemical compositions of the essential oils were also investigated. The GC/MS oils analysis showed that the main component of mentrasto essential oil is precocene I and of the main component of oregano essential oil is 4-terpineol. The results indicate that both essential oils can become an alternative for the control of aflatoxins in corn and soybeans. PMID:24926289

  4. Potential of essential oils for protection of grains contaminated by aflatoxin produced by Aspergillus flavus.

    PubMed

    Esper, Renata H; Gonçalez, Edlayne; Marques, Marcia O M; Felicio, Roberto C; Felicio, Joana D

    2014-01-01

    Aflatoxin B1 (AFB1) is a highly toxic and carcinogenic metabolite produced by Aspergillus species on food and agricultural commodities. Inhibitory effects of essential oils of Ageratum conyzoides (mentrasto) and Origanum vulgare (oregano) on the mycelial growth and aflatoxin B1 production by Aspergillus flavus have been studied previously in culture medium. The aim of this study was to evaluate aflatoxin B1 production by Aspergillus flavus in real food systems (corn and soybean) treated with Ageratum conyzoides (mentrasto) and Origanum vulgare (oregano) essential oils. Samples with 60 g of the grains were treated with different volumes of essential oils, 200, 100, 50, and 10 μL for oregano and 50, 30, 15, and 10 μL for mentrasto. Fungal growth was evaluated by disk diffusion method. Aflatoxin B1 production was evaluated inoculating suspensions of A. flavus containing 1.3 × 10(5) spores/mL in 60 g of grains (corn and soybeans) after adjusting the water activity at 0.94. Aflatoxin was quantified by photodensitometry. Fungal growth and aflatoxin production were inhibited by essential oils, but the mentrasto oil was more effective in soybeans than that of oregano. On the other hand, in corn samples, the oregano essential oil was more effective than that of mentrasto. Chemical compositions of the essential oils were also investigated. The GC/MS oils analysis showed that the main component of mentrasto essential oil is precocene I and of the main component of oregano essential oil is 4-terpineol. The results indicate that both essential oils can become an alternative for the control of aflatoxins in corn and soybeans.

  5. Allelopathic assessment of selected common weeds in Malaysia

    NASA Astrophysics Data System (ADS)

    Nurul Ain, M. B.; Nornasuha, Y.; Ismail, B. S.

    2016-11-01

    A laboratory study was conducted to evaluate the allelopathic potential of eight common weed species in Malaysia, namely, Ageratum conyzoides, Tridax procumbens, Cyperus iria, Fimbristylis miliacea, Eleusine indica, Imperata cylindrica, Lygodium flexuosum and Nephrolepis biserrata of different morphological characteristics (broadleaves, sedges, grasses and ferns). The allelopathic study of these weeds was carried out by testing the leaf litter leachate through the Sandwich method and the volatile compounds of these weeds through the Dish pack method with three replicates for each donor species. The results obtained from both methods were statistically analyzed and the means had converted to percentage growth inhibition to determine the inhibition pattern on the radicle and hypocotyl growth of lettuce seedlings. Among the eight weed species tested, Ageratum conyzoides showed the strongest growth inhibition on lettuce radicle elongation (86%) in the sandwich bioassay compared to the control, followed by Tridax procumbens (71%), which both species being broadleaves weeds. In the dish pack bioassay Lygodium flexuosum (fern) demonstrated maximum inhibition on the growth the radicle and hypocotyl for each different distance from the source well. On the other hand, two weed species exhibited enhanced on the growth radicle and hypocotyl when compared to that of the control in dish pack bioassay. Nephrolepis biserrata and Fimbristylis miliacea were the species that showed the highest growth stimulatory effect. The results presented can be utilized as benchmark information for further research on the elucidation of leachates and volatile chemicals involved in allelopathy in nature. The information can also be helpful in the development of new bioactive chemicals from natural products in weed control strategies.

  6. Family Leave Legislation in the U.S. House: Voting on the Family and Medical Leave Act of 1990.

    ERIC Educational Resources Information Center

    Monroe, Pamela A.; And Others

    1995-01-01

    A model of roll call voting by House members on the Family and Medial Leave Act (FMLA) of 1990 was tested. Found that support for the FMLA was tied to a range of dispositional and contextual demand variables: conservatism, presidential support, etc. The model accurately predicted 90% of the votes. (RJM)

  7. 29 CFR 825.310 - Certification for leave taken to care for a covered servicemember (military caregiver leave).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., whether the covered servicemember's injury or illness existed before the beginning of the servicemember's... therapy for an injury or illness that is a physical or mental condition that substantially impairs the... provider. When leave is taken to care for a covered servicemember with a serious injury or illness,...

  8. Movement of Water from Old to Young Leaves in Three Species of Succulents

    PubMed Central

    RABAS, A. R.; MARTIN, C. E.

    2003-01-01

    A hypothetical adaptive response of succulent plants to drought‐stress is the redistribution of water from old to young leaves. We examined the effects of possible movement of water from old to young leaves in three succulent species, Carpobrotus edulis (weak CAM‐inducible), Kalanchoe tubiflora (CAM) and Sedum spectabile (possibly a CAM‐cycler or CAM‐inducible). Old leaves were removed from plants, and photosynthesis, transpiration, f. wt : d. wt ratios, diurnal acid fluctuations, stomatal conductance and internal CO2 concentrations of the remaining young leaves were measured during drought‐stress. Comparison was made with plants retaining old leaves. There was no evidence that water moved from old to young leaves during drought‐stress as previously hypothesized. Only in drought‐stressed plants of K. tubiflora, were photosynthetic and transpiration rates of young leaves greater on shoots with old leaves removed compared with attached. There was a trend in all species for greater fluctuations in acidity in young leaves on shoots that lacked older leaves. For two of the three species studied, the f. wt : d. wt ratios of young leaves were greater under drought‐stress, on shoots with old leaves removed than with them attached. Absence of old leaves may reduce competition for water with young leaves, which consequently have higher water content and greater photosynthetic rates. PMID:12907468

  9. Movement of water from old to young leaves in three species of succulents.

    PubMed

    Rabas, A R; Martin, C E

    2003-10-01

    A hypothetical adaptive response of succulent plants to drought-stress is the redistribution of water from old to young leaves. We examined the effects of possible movement of water from old to young leaves in three succulent species, Carpobrotus edulis (weak CAM-inducible), Kalanchoe tubiflora (CAM) and Sedum spectabile (possibly a CAM-cycler or CAM-inducible). Old leaves were removed from plants, and photosynthesis, transpiration, f. wt : d. wt ratios, diurnal acid fluctuations, stomatal conductance and internal CO2 concentrations of the remaining young leaves were measured during drought-stress. Comparison was made with plants retaining old leaves. There was no evidence that water moved from old to young leaves during drought-stress as previously hypothesized. Only in drought-stressed plants of K. tubiflora, were photosynthetic and transpiration rates of young leaves greater on shoots with old leaves removed compared with attached. There was a trend in all species for greater fluctuations in acidity in young leaves on shoots that lacked older leaves. For two of the three species studied, the f. wt : d. wt ratios of young leaves were greater under drought-stress, on shoots with old leaves removed than with them attached. Absence of old leaves may reduce competition for water with young leaves, which consequently have higher water content and greater photosynthetic rates.

  10. Pharmacognostic Specifications and Lawsone Content of Lawsonia inermis Leaves

    PubMed Central

    Charoensup, Rawiwan; Duangyod, Thidarat; Palanuvej, Chanida; Ruangrungsi, Nijsiri

    2017-01-01

    Background: Lawsonia inermis L. has been used as a traditional or folk medicine for the treatment of a wide range of skin infectious diseases. Objective: The objective of this study was to determine the pharmacognostic specifications and lawsone contents of L. inermis leaves. Materials and Methods: The pharmacognostic specifications of L. inermis leaves from 12 sources were evaluated according to the WHO guideline of quality control method for medicinal plant materials. The lawsone contents were analyzed by thin-layer chromatography (TLC) coupled with densitometry and image analysis. Results: Microscopic evaluation of L. inermis powders showed the fragment of mesophyll, fragment of parenchyma, epidermis layer with stomata, and the rosette crystal of calcium oxalate. Physicochemical parameters revealed that total ash, acid-insoluble ash, loss on drying, and water content should be not <6.98, 1.12, 8.08, and 9.86% of dried weight, respectively, whereas ethanol and water extractive values should be not < 19.67 and 23.06% of dried weight, respectively. The content of lawsone in L. inermis leaves by TLC-densitometry was found to be 0.76 ± 0.05 g/100 g of dried crude drug, whereas the lawsone content evaluation by TLC image analysis was found to be 0.87 ± 0.11 g/100 g of dried crude drug. The validation of the methods revealed that both TLC-densitometry and TLC image analysis showed a good sensitivity and accuracy for lawsone quantitation in L. inermis. Conclusion: The pharmacognostic specifications could be used as the standardization data of L. inermis leaves, and the development of TLC method could be applied to determine lawsone content in this plant material. SUMMARY The pharmacognostic specification of Lawsonia inermis leaves could be used as the standardization data of L. inermis leaves in Thailand.Both TLC-densitometry and TLC image analysis showed a good sensitivity and accuracy for lawsone quantitation. Abbreviations Used: LOD: Limit of detection; LOQ: Limit

  11. Commentary: what role for the family and Medical Leave Act in long-term care policy?

    PubMed

    Wisensale, Steven K

    2006-01-01

    The Family and Medical Leave Act provides unpaid leave but a key component is its intergenerational structure, permitting employees to take time off from work to care for an infant as well as an ill elderly parent. However, in an effort to provide paid leave, 23 of 28 states dropped the elder care provision in new initiatives introduced between 2000 and 2003. This article argues that in reforming leave policy in the future, the leave should be paid, remain intergenerational, cover more workers, and be adaptable to changing family patterns in an aging society. Also discussed is California's paid leave law, which meets these criteria.

  12. Oriented cell division shapes carnivorous pitcher leaves of Sarracenia purpurea.

    PubMed

    Fukushima, Kenji; Fujita, Hironori; Yamaguchi, Takahiro; Kawaguchi, Masayoshi; Tsukaya, Hirokazu; Hasebe, Mitsuyasu

    2015-03-16

    Complex morphology is an evolutionary outcome of phenotypic diversification. In some carnivorous plants, the ancestral planar leaf has been modified to form a pitcher shape. However, how leaf development was altered during evolution remains unknown. Here we show that the pitcher leaves of Sarracenia purpurea develop through cell division patterns of adaxial tissues that are distinct from those in bifacial and peltate leaves, subsequent to standard expression of adaxial and abaxial marker genes. Differences in the orientation of cell divisions in the adaxial domain cause bifacial growth in the distal region and adaxial ridge protrusion in the middle region. These different growth patterns establish pitcher morphology. A computer simulation suggests that the cell division plane is critical for the pitcher morphogenesis. Our results imply that tissue-specific changes in the orientation of cell division underlie the development of a morphologically complex leaf.

  13. Diuretic activity of leaves of garcinia cambogia in rats.

    PubMed

    Mathew, Githa E; Mathew, B; Shaneeb, M M; Nyanthara, B

    2011-03-01

    The present study was undertaken to establish the diuretic activity of ethanol and aqueous extract of dried leaves of Garcinia cambogia in rats. Aqueous and ethanol extracts of leaves were administered to experimental rats orally at doses of 100 and 200 mg/kg and compared with furosemide (20 mg/kg, intraperitoneally) as the standard. The parameters measured for diuretic activity were total urine volume, urine concentration electrolytes such as sodium, potassium and chloride have been evaluated . The rats treated with ethanol extract of Garcinia cambogia and aqueous extract of Garcinia cambogia in a dose of 100 and 200 mg/kg showed higher urine output when compared to the respective control. Both ethanol and aqueous extracts have showed a significant dose-dependent increase in the excretion of electrolytes when compared to the control group.

  14. Antimicrobial acylphloroglucinols from the leaves of Rhodomyrtus tomentosa.

    PubMed

    Liu, Hong-Xin; Tan, Hai-Bo; Qiu, Sheng-Xiang

    2016-06-01

    Phytochemical study on the leaves of Rhodomyrtus tomentosa resulted in the isolation of fourteen compounds including a new acylphloroglucinol, named tomentosone C (1), and a new flavonol glycoside, namely myricetin-3,7,3'-trimethyl ether-5'-O-β-glucopyranoside (2). Their structures were characterized by spectral data interpretation for new structures and in comparison with published data for known compounds. The antimicrobial activity evaluation revealed that 1 and the known acylphloroglucinol rhodomyrtone (3) exhibited significant antimicrobial activity with MIC 3.66 and 1.83 μg ml(-1), respectively, toward Staphylococcus aureus, responsible for the antimicrobial activity observed with the n-hexane and EtOAc-soluble fraction of the ethanol extract of R. tomentosa leaves.

  15. Optimization of pressurized liquid extraction of Piper gaudichaudianum Kunth leaves.

    PubMed

    Péres, Valéria Flores; Saffi, Jenifer; Melecchi, Maria Inês S; Abad, Fernanda C; Martinez, Migdalia M; Oliveira, Eniz Conceição; Jacques, Rosângela Assis; Caramão, Elina B

    2006-02-10

    Piperaceae family is original from tropical regions and it shows more than 700 species around the world. Piper gaudichaudianum Kunth is the specie more abundant in Brazil, occurring from Northeast to South Brazil. In this paper, it was investigated the influence of some experimental parameters on the pressurized liquid extraction (PLE) of P. gaudichaudianum Kunth leaves, using petroleum ether as extractor solvent. The optimization of the main variables involved in the PLE process (extraction temperature and time) has been done by response surface methodology (RSM) using, as responses, the extraction yield and the chromatographic profile (GC/MS) of the extracts. The optimized procedure employed 3 g of ground leaves, 10 min of extraction and one cycle of extraction at 85 degrees C. The major compounds present in the petroleum ether extracts were: palmitic acid, stearic acid and nerolidol. The results presented in this work show the possibility of using a fast and easy process to recover compounds from P. gaudichaudianum Kunth.

  16. A potential low-coumarin cinnamon substitute: Cinnamomum osmophloeum leaves.

    PubMed

    Yeh, Ting-Feng; Lin, Chun-Ya; Chang, Shang-Tzen

    2014-02-19

    The essential oils from leaves of Taiwan's indigenous cinnamon (Cinnamomum osmophloeum ct. cinnamaldehyde) have similar constituents as compared to that from commercial bark cinnamons. This indigenous cinnamon has been proven to have excellent bioactivities. To understand whether this indigenous cinnamon contains a high level of the hepatotoxic compound, coumarin, as often seen in Cassia cinnamons, current research focused on determining the coumarin content in this indigenous cinnamon and screening the low-coumarin clones. The results demonstrated that the coumarin contents in all tested indigenous cinnamon clones were much lower than that found in Cassia cinnamons. In addition, this indigenous cinnamon contains about 80% (w/w) of cinnamaldehyde and 0.4-2.7% (w/w) of eugenol in its leaf essential oils. This combination could provide this indigenous cinnamon a better shelf life compared to that of regular commercial cinnamons. These results suggested that leaves of this indigenous cinnamon could be a potential resource for a safer cinnamon substitute.

  17. Drought-Responsive Mechanisms in Plant Leaves Revealed by Proteomics.

    PubMed

    Wang, Xiaoli; Cai, Xiaofeng; Xu, Chenxi; Wang, Quanhua; Dai, Shaojun

    2016-10-18

    Plant drought tolerance is a complex trait that requires a global view to understand its underlying mechanism. The proteomic aspects of plant drought response have been extensively investigated in model plants, crops and wood plants. In this review, we summarize recent proteomic studies on drought response in leaves to reveal the common and specialized drought-responsive mechanisms in different plants. Although drought-responsive proteins exhibit various patterns depending on plant species, genotypes and stress intensity, proteomic analyses show that dominant changes occurred in sensing and signal transduction, reactive oxygen species scavenging, osmotic regulation, gene expression, protein synthesis/turnover, cell structure modulation, as well as carbohydrate and energy metabolism. In combination with physiological and molecular results, proteomic studies in leaves have helped to discover some potential proteins and/or metabolic pathways for drought tolerance. These findings provide new clues for understanding the molecular basis of plant drought tolerance.

  18. Drought-Responsive Mechanisms in Plant Leaves Revealed by Proteomics

    PubMed Central

    Wang, Xiaoli; Cai, Xiaofeng; Xu, Chenxi; Wang, Quanhua; Dai, Shaojun

    2016-01-01

    Plant drought tolerance is a complex trait that requires a global view to understand its underlying mechanism. The proteomic aspects of plant drought response have been extensively investigated in model plants, crops and wood plants. In this review, we summarize recent proteomic studies on drought response in leaves to reveal the common and specialized drought-responsive mechanisms in different plants. Although drought-responsive proteins exhibit various patterns depending on plant species, genotypes and stress intensity, proteomic analyses show that dominant changes occurred in sensing and signal transduction, reactive oxygen species scavenging, osmotic regulation, gene expression, protein synthesis/turnover, cell structure modulation, as well as carbohydrate and energy metabolism. In combination with physiological and molecular results, proteomic studies in leaves have helped to discover some potential proteins and/or metabolic pathways for drought tolerance. These findings provide new clues for understanding the molecular basis of plant drought tolerance. PMID:27763546

  19. Fern leaves and cauliflower curds are not fractals.

    PubMed

    Lev-Yadun, Simcha

    2012-05-01

    The popular demonstration of drawing a mature fern leaf as expressed by Barnsley's fractal method is mathematically and visually very attractive but anatomically and developmentally misleading, and thus has limited, if any, biological significance. The same is true for the fractal demonstration of the external features of cauliflower curds. Actual fern leaves and cauliflower curds have a very small number of anatomically variable and non-iterating bifurcations, which superficially look self-similar, but do not allow for scaling down of their structure as real fractals do. Moreover, fern leaves and cauliflower curds develop from the inside out through a process totally different from fractal drawing procedures. The above cases demonstrate a general problem of using mathematical tools to investigate or illustrate biological phenomena in an irrelevant manner. A realistic set of mathematical equations to describe fern leaf or cauliflower curd development is needed.

  20. Underground leaves of Philcoxia trap and digest nematodes

    PubMed Central

    Pereira, Caio G.; Almenara, Daniela P.; Winter, Carlos E.; Fritsch, Peter W.; Lambers, Hans; Oliveira, Rafael S.

    2012-01-01

    The recently described genus Philcoxia comprises three species restricted to well lit and low-nutrient soils in the Brazilian Cerrado. The morphological and habitat similarities of Philcoxia to those of some carnivorous plants, along with recent observations of nematodes over its subterranean leaves, prompted the suggestion that the genus is carnivorous. Here we report compelling evidence of carnivory in Philcoxia of the Plantaginaceae, a family in which no carnivorous members are otherwise known. We also document both a unique capturing strategy for carnivorous plants and a case of a plant that traps and digests nematodes with underground adhesive leaves. Our findings illustrate how much can still be discovered about the origin, distribution, and frequency of the carnivorous syndrome in angiosperms and, more generally, about the diversity of nutrient-acquisition mechanisms that have evolved in plants growing in severely nutrient-impoverished environments such as the Brazilian Cerrado, one of the world's 34 biodiversity hotspots. PMID:22232687

  1. Low Reynolds number flow near tiny leaves, stems, and trichomes

    NASA Astrophysics Data System (ADS)

    Strickland, Christopher; Pasour, Virginia; Miller, Laura

    2016-11-01

    In terrestrial and aquatic environments such as forest canopies, grass fields, and seagrass beds, the density and shape of trunks, branches, stems, leaves and trichomes (the hairs or fine outgrowths on plants) can drastically alter both the average wind speed and profile through these environments and near each plant. While many studies of flow in these environments have focused on bulk properties of the flow at scales on the order of meters, the low Reynolds number flow close to vegetative structures is especially complex and relevant to nutrient exchange. Using three-dimensional immersed boundary simulations, we resolve the flow around trichomes and small leaves and quantify velocities, shear stresses, and mixing while varying the height and density of idealized structures. National Science Foundation Grant DMS-1127914 to the Statistical and Applied Mathematical Sciences Institute, and the Army Research Office.

  2. Utilization of Anting-Anting (Acalypha indica) Leaves as Antibacterial

    NASA Astrophysics Data System (ADS)

    Batubara, Irmanida; Wahyuni, Wulan Tri; Firdaus, Imam

    2016-01-01

    Anting-anting (Acalypha indica) plants is a species of plant having catkin type of inflorescence. This research aims to utilize anting-anting as antibacterial toward Streptococcus mutans and degradation of biofilm on teeth. Anting-anting leaves were extracted by maceration technique using methanol, chloroform, and n-hexane. Antibacterial and biofilm degradation assays were performed using microdilution technique with 96 well. n-Hexane extracts of anting-anting leaves gave the best antibacterial potency with minimum inhibitory concentration and minimum bactericidal concentration value of 500 μg/mL and exhibited good biofilm degradation activity. Fraction of F3 obtained from fractionation of n-hexane's extract with column chromatography was a potential for degradation of biofilm with IC50 value of 56.82 μg/mL. Alkaloid was suggested as antibacterial and degradation of biofilm in the active fraction.

  3. Droplet fragmentation on leaves shapes foliar disease dispersal

    NASA Astrophysics Data System (ADS)

    Bourouiba, Lydia; Gilet, Tristan

    2015-11-01

    Although the dispersal of pathogens from plant to plant remains poorly understood, a strong statistical correlation exists between rainfall patterns and plant disease outbreaks. This correlation suggests that rain is a culprit in the dispersal of foliar pathogens. In this combined experimental and theoretical study, we unveil the mechanisms at play when a raindrop impacts an infected plant leaf. We identify two main fragmentation processes that shape rain-induced dispersal mechanisms. In both, pathogens are initially contained in water residues left on leaves by previous raindrops. As most leaves are partially wetting, residues take the shape of sessile drops. The impact of another raindrop in the vicinity triggers fragmentation of the sessile drop and subsequent ejection of contaminated droplets towards neighboring plants. Each scenario yields a different distribution of ejected droplets and brings a distinct contribution to the epidemic onset pattern. We show that leaf mechanical properties govern both fragmentation scenarios. Dimensionless parameters and scaling laws are provided to rationalize our observations.

  4. Oriented cell division shapes carnivorous pitcher leaves of Sarracenia purpurea

    PubMed Central

    Fukushima, Kenji; Fujita, Hironori; Yamaguchi, Takahiro; Kawaguchi, Masayoshi; Tsukaya, Hirokazu; Hasebe, Mitsuyasu

    2015-01-01

    Complex morphology is an evolutionary outcome of phenotypic diversification. In some carnivorous plants, the ancestral planar leaf has been modified to form a pitcher shape. However, how leaf development was altered during evolution remains unknown. Here we show that the pitcher leaves of Sarracenia purpurea develop through cell division patterns of adaxial tissues that are distinct from those in bifacial and peltate leaves, subsequent to standard expression of adaxial and abaxial marker genes. Differences in the orientation of cell divisions in the adaxial domain cause bifacial growth in the distal region and adaxial ridge protrusion in the middle region. These different growth patterns establish pitcher morphology. A computer simulation suggests that the cell division plane is critical for the pitcher morphogenesis. Our results imply that tissue-specific changes in the orientation of cell division underlie the development of a morphologically complex leaf. PMID:25774486

  5. Antibacterial Constituents of Hainan Morinda citrifolia (Noni) Leaves.

    PubMed

    Zhang, Wei-Min; Wang, Wei; Zhang, Jing-Jing; Wang, Zhi-Rong; Wang, Yu; Hao, Wang-Jun; Huang, Wu-Yang

    2016-05-01

    Noni (Morinda citrifolia L.) is an edible and medicinal plant distributed in Hainan, China. The antibacterial activities of the extracts of water (WE), petroleum ether (PEE), ethyl acetate (EAE), chloroform (CE), and n-butanol (BE) were assayed by the disk diffusion method. The results showed that the extracts from Noni leaves possessed antibacterial effects against Bacillus subtilis, Escherichia coli, Proteus vulgaris, and Staphylococcus aureus. Among 5 different extracts, the BE produced the best antibacterial activity. The samples were first extracted by ethanol, and the primary compounds in the BE fraction of ethanol extract was further isolated and identified. Six phenolic compounds, including 5, 15-dimethylmorindol, ferulic acid, p-hydroxycinamic acid, methyl 4-hydroxybenzoate, methyl ferulate, and methyl 4-hydroxycinnamate, were identifiedby NMR. The results indicated that the phenolic compounds might significantly contribute to antibacterial activities of Noni leaves.

  6. Identification of phenylpropanoids in fig (Ficus carica L.) leaves.

    PubMed

    Takahashi, Toru; Okiura, Aya; Saito, Keita; Kohno, Masahiro

    2014-10-15

    In this study, the phenylpropanoid composition and antioxidant activity of identified components in fig (Ficus carica L.) leaves were examined. Known polyphenols rutin, isoschaftoside, isoquercetin, and chlorogenic acid were identified. Furthermore, caffeoylmalic acid (CMA) was the most abundant polyphenol and was identified for the first time. CMA exhibited antioxidant activity similar to that of vitamin C or catechin. Psoralen and bergapten were identified as known furanocoumarins, with psoralen being the most abundant. Moreover, psoralic acid glucoside (PAG) was identified for the first time. As a precursor of psoralen, PAG content was equivalent to the psoralen content in moles. Notably, the content of these compounds varied between the five fig varieties, and the furanocoumarin and PAG contents varied more than that of the polyphenols. Further investigations concerning the influence of CMA and PAG on human health are necessary to elucidate functionalities of fig leaves.

  7. Effects of Raman scattering on the water-leaving radiance

    NASA Technical Reports Server (NTRS)

    Waters, Kirk J.

    1995-01-01

    The contribution of Raman scattering to the water-leaving radiance is examined using Monte Carlo simulations. Exit angle information is retained, allowing a comparison of different satellite viewing directions. Chlorophyll values of 0.0, 0.01, 0.1, and 1.0 mg Chl/cu m are simulated. Little directional variability is found, with the exception of the direct solar backscatter direction. The wavelength variability is greatest for low chlorophyll concentrations and is negligible for 1.0 mg Chl/cu m. At 550 nm the Raman contribution ranges from approximately 18% of the total water-leaving radiance for pure water to 3% for 1.0 mg Chl/cu m. At 440 nm the range is from 6% to 2%, indicating that Raman scattering will impact radiance ratios for ocean color satellite algorithms.

  8. Phomalactone from a Phytopathogenic Fungus Infecting ZINNIA elegans (ASTERACEAE) Leaves.

    PubMed

    Meepagala, Kumudini M; Johnson, Robert D; Techen, Natascha; Wedge, David E; Duke, Stephen O

    2015-07-01

    Zinnia elegans Jacq. plants are infected by a fungus that causes dark red spots with necrosis on leaves, particularly in late spring to the middle of summer in the Mid-South of the United States. This fungal disease causes the leaves to wilt and eventually kills the plant. The fungus was isolated, cultured in potato dextrose broth, and identified as Nigrospora sphaerica by molecular techniques. Two major lactone metabolites (phomalactone and catenioblin A) were isolated from liquid culture of N. sphaerica isolated from Z. elegans. When injected into leaves of Z. elegans, phomalactone caused lesions similar to those of the fungus. The lesion sizes were proportional to the concentration of the phomalactone. Phomalactone, but not catenioblin A, was phytotoxic to Z. elegans and other plant species by inhibition of seedling growth and by causing electrolyte leakage from photosynthetic tissues of both Z. elegans leaves and cucumber cotyledons. This latter effect may be related to the wilting caused by the fungus in mature Z. elegans plants. Phomalactone was moderately fungicidal to Coletotrichum fragariae and two Phomopsis species, indicating that the compound may keep certain other fungi from encroaching into plant tissue that N. sphaerica has infected. Production of large amounts of phomalactone by N. sphaerica contributes to the pathogenic behavior of this fungus, and may have other ecological functions in the interaction of N. sphaerica with other fungi. This is the first report of isolation of catenioblin A from a plant pathogenic fungus. The function of catenioblin A is unclear, as it was neither significantly phyto- nor fungitoxic.

  9. Extraction of high-quality RNA from rubber tree leaves.

    PubMed

    Deng, Liu-Hong; Luo, Ming-Wu; Zhang, Chun-Fa; Zeng, Hui-Cai

    2012-01-01

    A specific technique capable of producing high-quality RNA for rapid amplification of cDNA ends (RACE) was established for challenging tissues: leaves of the rubber tree. Total RNA was extracted by cetyltrimethylammonium bromide (CTAB)-LiCl combined with TRIzol reagent. The isolated RNA was highly intact. With RNA as template, full-length cDNA was obtained (NCBI, AY461413) by RACE.

  10. IEQ and the impact on employee sick leave

    SciTech Connect

    Kumar, Satish; Fisk, William J.

    2002-08-01

    When selecting minimum ventilation rates, employers should balance the well-recognized energy costs of providing higher minimum ventilation rates with the expected, but less well quantified, health benefits from a higher ventilation rate. This is a summary of the paper by Milton, et al. that found low employee sick leave associated with high ventilation rates in a set of buildings located in Massachusetts. A simple cost-benefit analysis also is presented.

  11. Malate synthesis by dark carbon dioxide fixation in leaves.

    PubMed

    Levi, C; Perchorowicz, J T; Gibbs, M

    1978-04-01

    The rates of dark CO(2) fixation and the label distribution in malate following dark (14)CO(2) fixation in a C-4 plant (maize), a C-3 plant (sunflower), and two Crassulacean acid metabolism plants (Bryophyllum calycinum and Kalanchoë diagremontianum leaves and plantlets) are compared. Within the first 30 minutes of dark (14)CO(2) fixation, leaves of maize, B. calycinum, and sunflower, and K. diagremontianum plantlets fix CO(2) at rates of 1.4, 3.4, 0.23, and 1.0 mumoles of CO(2)/mg of chlorophyll. hour, respectively. Net CO(2) fixation stops within 3 hours in maize and sunflower, but Crassulaceans continue fixing CO(2) for the duration of the 23-hour experiment.A bacterial procedure using Lactobacillus plantarum ATCC No. 8014 and one using malic enzyme to remove the beta-carboxyl (C(4)) from malate are compared. It is reported that highly purified malic enzyme and the bacterial method provide equivalent results. Less purified malic enzyme may overestimate the label in C(4) as much as 15 to 20%.The contribution of carbon atom 1 of malate is between 18 and 21% of the total carboxyl label after 1 minute of dark CO(2) fixation. Isotopic labeling in the two carboxyls approached unity with time. The rate of increase is greatest in sunflower leaves and Kalanchoë plantlets. In addition, Kalanchoë leaves fix (14)CO(2) more rapidly than Kalanchoë plantlets and the equilibration of the malate carboxyls occurs more slowly. The rates of fixation and the randomization are tissue-specific. The rate of fixation does not correlate with the rate of randomization of isotope in the malate carboxyls.

  12. Malate Synthesis by Dark Carbon Dioxide Fixation in Leaves 1

    PubMed Central

    Levi, Carolyn; Perchorowicz, John T.; Gibbs, Martin

    1978-01-01

    The rates of dark CO2 fixation and the label distribution in malate following dark 14CO2 fixation in a C-4 plant (maize), a C-3 plant (sunflower), and two Crassulacean acid metabolism plants (Bryophyllum calycinum and Kalanchoë diagremontianum leaves and plantlets) are compared. Within the first 30 minutes of dark 14CO2 fixation, leaves of maize, B. calycinum, and sunflower, and K. diagremontianum plantlets fix CO2 at rates of 1.4, 3.4, 0.23, and 1.0 μmoles of CO2/mg of chlorophyll· hour, respectively. Net CO2 fixation stops within 3 hours in maize and sunflower, but Crassulaceans continue fixing CO2 for the duration of the 23-hour experiment. A bacterial procedure using Lactobacillus plantarum ATCC No. 8014 and one using malic enzyme to remove the β-carboxyl (C4) from malate are compared. It is reported that highly purified malic enzyme and the bacterial method provide equivalent results. Less purified malic enzyme may overestimate the label in C4 as much as 15 to 20%. The contribution of carbon atom 1 of malate is between 18 and 21% of the total carboxyl label after 1 minute of dark CO2 fixation. Isotopic labeling in the two carboxyls approached unity with time. The rate of increase is greatest in sunflower leaves and Kalanchoë plantlets. In addition, Kalanchoë leaves fix 14CO2 more rapidly than Kalanchoë plantlets and the equilibration of the malate carboxyls occurs more slowly. The rates of fixation and the randomization are tissue-specific. The rate of fixation does not correlate with the rate of randomization of isotope in the malate carboxyls. PMID:16660319

  13. Effects of gravity on transpiration of plant leaves.

    PubMed

    Hirai, Hiroaki; Kitaya, Yoshiaki

    2009-04-01

    To clarify effects of gravity on the water vapor exchange between plants and the ambient air, we evaluated the transpiration rate of plant leaves at 0.01, 1.0, and 2.0 g for 20 s each during parabolic airplane flights. The transpiration rates of a strawberry leaf and a replica leaf made of wet cloth were determined using a chamber method with humidity sensors. Absolute humidity at 3 and 8 mm below the lower surface of leaves was measured to evaluate the effect of gravity on humidity near leaves and estimate their transpiration rate. The transpiration rate of the replica leaf decreased by 42% with decreasing gravity levels from 1.0 to 0.01 g and increased by 31% with increasing gravity levels from 1.0 to 2.0 g. Absolute humidity near the intact strawberry leaf was 5 g m(-3) at ambient absolute humidity of 2.3 g m(-3) and gravity of 1.0 g. The absolute humidity increased by 2.5 g m(-3) with decreasing gravity levels from 1.0 to 0.01 g. The transpiration rate of the intact leaf decreased by 46% with decreasing gravity levels from 1.0 to 0.01 g and increased by 32% with increasing gravity levels from 1.0 to 2.0 g. We confirmed that the transpiration rate of leaves was suppressed by retarding the water vapor transfer due to restricted free air convection under microgravity conditions.

  14. Variegation in Arum italicum leaves. A structural-functional study.

    PubMed

    La Rocca, Nicoletta; Rascio, Nicoletta; Pupillo, Paolo

    2011-12-01

    The presence of pale-green flecks on leaves (speckling) is a frequent character among herbaceous species from shady places and is usually due to local loosening of palisade tissue (air space type of variegation). In the winter-green Arum italicum L. (Araceae), dark-green areas of variegated leaf blades are ca. 400 μm thick with a chlorophyll content of 1080 mg m⁻² and a palisade parenchyma consisting of a double layer of oblong cells. Pale-green areas are 25% thinner, have 26% less chlorophyll and contain a single, loose layer of short palisade cells. Full-green leaves generally present only one compact layer of cylindrical palisade cells and the same pigment content as dark-green sectors, but the leaf blade is 13% thinner. A spongy parenchyma with extensive air space is present in all leaf types. Green cells of all tissues have normal chloroplasts. Assays of photosynthetic activities by chlorophyll fluorescence imaging and O₂ exchange measurements showed that variegated pale-green and dark-green sectors as well as full-green leaves have comparable photosynthetic activities on a leaf area basis at saturating illumination. However, full-green leaves require a higher saturating light with respect to variegated sectors, and pale-green sectors support relatively higher photosynthesis rates on a chlorophyll basis. We conclude that i) variegation in this species depends on number and organization of palisade cell layers and can be defined as a "variable palisade" type, and ii) the variegated habit has no limiting effects on the photosynthetic energy budget of A. italicum, consistent with the presence of variegated plants side by side to full-green ones in natural populations.

  15. In vitro Evaluation of Anthelmintic Activity of Nauclea orientalis Leaves

    PubMed Central

    Raghavamma, S. T. V.; Rao, N. Rama

    2010-01-01

    Antianthelmintic activity of successive extracts (chloroform, acetone, ethanol and aqueous) of Nauclea orientalis leaves were evaluated separately on adult Indian earthworm (Pheretima posthuma) and compared with that of albendazole. It was found that the extracts exhibited, respectively dose-dependent action and inhibition of spontaneous motility (paralysis) and death of earthworms. The results indicated that the chloroform, ethyl acetate and ethanol extracts were more potent. PMID:21218070

  16. Some studies on anaerobic decomposition of leucaena leucocephala leaves

    SciTech Connect

    Torane, J.V.; Lokhande, C.D.; Pawar, S.H. )

    1990-01-01

    Batch type anaerobic decomposition process in leucaena leucocephala plant material (leaves) has been carried out under mesophilic conditions (below 35{degrees}C). The results of studies involving variations in pH, conductivity, temperature, and optical density of digester slurry for four weeks are reported. The gas production rate was also studied which reveals that the use of leucaena leucocephala for biogas production will be helpful.

  17. Spectral Dependence of Chlorophyll Biosynthesis Pathways in Plant Leaves.

    PubMed

    Belyaeva, O B; Litvin, F F

    2015-12-01

    This review covers studies on the dependence of chlorophyll photobiosynthesis reactions from protochlorophyllide on the spectral composition of actinic light. A general scheme of the reaction sequence for the photochemical stage in chlorophyll biosynthesis for etiolated plant leaves is presented. Comparative analysis of the data shows that the use of light with varied wavelengths for etiolated plant illumination reveals parallel transformation pathways of different protochlorophyllide forms into chlorophyllide, including a pathway for early photosystem II reaction center P-680 pigment formation.

  18. Pregnancy and employment leave: legal precedents and future policy.

    PubMed

    Gardin, S K; Richwald, G A

    1986-01-01

    An estimated 85% of female workers in the US become pregnant during their working lives; 62% of married US women were employed for some period during the 12 months preceding childbirth. Historically, US legislation has assumed a protectionist policy with regard to restricting prenatal and postpartum employment, yet this stance has not been backed up by protection of income, benefits, reinstatement, or seniority. The passage in 1964 of Title VII of the Federal Civil Rights Act banning discrimination on the basis of sex triggered a long string of legal battles fought on the premise that pregnancy is a disability. As a result of Congressional efforts, an amendment to Title VII--the Pregnancy Discrimination Act--was passed in 1978. This law requires that women disabled due to pregnancy or childbirth be provided with the same benefits as those provided other disabled employees. However, the law does not require an employer who does not provide disability benefits, paid sick leave, or medical benefits to other employees to provide them to pregnant women. A weakness of existing legislation is its failure to address the difficulties inherent in accommodating childbearing women in the labor force. Accommodation under the current employment system results in productivity disruption and financial losses for both employer and employee. In all other major industrial countries, maternity benefits such as paid leave before and after childbirth, reinstatement rights, and nursing breaks on the job are guaranteed through national legislation. Such benefits emanate from acknowledgment of women's essential participation in the labor force as well as their unique ability to give birth. Under a more flexible employment system, equal protection would not result in the denial of maternity leave to female employees, but rather the provision parental leave to male and female employees.

  19. Triterpenes and triterpenoid saponins from the leaves of Ilex kudincha.

    PubMed

    Zuo, Wen-Jian; Dai, Hao-Fu; Chen, Jing; Chen, Hui-Qin; Zhao, You-Xing; Mei, Wen-Li; Li, Xian; Wang, Jin-Hui

    2011-11-01

    One new triterpene, kudinchalactone A (1), and four new triterpenoid saponins, ilekudinchosides A-D (2- 5), were isolated from the leaves of Ilex kudincha C. J. Tseng along with eight known triterpenoids. These new compounds were elucidated by spectroscopic methods including 1D and 2D NMR, HR-TOF-MS, and CD spectra. Compounds 2, 3, 12, and 13 showed antibacterial activities against Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA).

  20. Bioactive limonoids from the leaves of Azaridachta indica (Neem).

    PubMed

    Gualtieri, Maria J; Malafronte, Nicola; Vassallo, Antonio; Braca, Alessandra; Cotugno, Roberta; Vasaturo, Michele; De Tommasi, Nunziatina; Dal Piaz, Fabrizio

    2014-03-28

    Eight new limonoids (1-8) and one new phenol glycoside (9), along with six known compounds, were isolated from the leaves of Azaridachta indica. The structures of 1-9 were elucidated on the basis of spectroscopic data analysis. Compounds isolated were assayed for their cytotoxicity against different cancer cell lines. Moreover, their ability to interact with the molecular chaperone Hsp90, affecting its biological activity, was tested.

  1. Ultrasonically assisted antioxidant extraction from grape stalks and olive leaves

    NASA Astrophysics Data System (ADS)

    Cárcel, Juan A.; García-Pérez, José V.; Mulet, Antonio; Rodríguez, Ligia; Riera, Enrique

    2010-01-01

    Grape stalks and olive leaves present high amount of phenolic compounds with antioxidant properties. The extraction of these compounds may be considered a way to increase in value both agro-food by-products. Ultrasound is widely applied in extraction due to its effects (cavitation, microstirring or sponge effect) over the process. The goal of this work was to address the application of ultrasound on the antioxidant extraction of olive leaves and grape stalk. For that purpose, the extraction of antioxidant compounds from grape stalks and olive leaves, previously dried at 100 °C, were carried out using a ethanolic solution (80 % v/v) at 60 °C. Extractions were carried out with (US; 30 kHz; 600W)) and agitation (AG) without ultrasound application. In the AG experiments, the solution was agitated with a stirrer. Samples were obtained at different extraction time (10, 30, 60, 120, 180, 240, 360, 480 and 1440 min) and their antioxidant capacity was measured using FRAP method. The Naik model was used to model the extraction kinetics, being identified the antioxidant capacity of extracts at the equilibrium (Y eq) and the initial velocity of extraction (Y eq/B). For grape stalks, the antioxidant capacity of extracts at the equilibrium (Y eq) and the initial velocity of extraction (Y eq/B) were higher in AG experiments than in US experiments. In the olive leaves extractions, the Y eq/B was of the same order for both treatments but Y eq was significantly higher for US experiments. The different influence of ultrasound for both by-products can be explained from their different geometry and structure.

  2. Triterpenoidal constituents of the leaves of Carissa carandas.

    PubMed

    Siddiqui, Bina S; Ghani, Usman; Ali, Syed Tahir; Usmani, Shahid Badar; Begum, Sabira

    2003-06-01

    Studies undertaken on the fresh leaves of Carissa carandas have led to the isolation of four pentacyclic triterpenoids (1-4) including one new constituent carissin (1) and two hitherto unreported compounds 2 and 3. The structure of the new triterpenoid has been elucidated as 3beta-hydroxy-27-E-feruloyloxyurs-12-en-28-oic acid. Compelete assignment of the protons of 2 has also been made based on 2D NMR studies.

  3. Is Leaving the Middle East a Viable Option

    DTIC Science & Technology

    2008-01-01

    Fellow Stephen Sloan Ph.D., Comparative Politics University of Central Florida Robert G. Spulak, Jr. Ph.D., Physics/Nuclear Engineering Sandia ...the Bush (Praeger, 1981); Soviet and Chinese Aid to African Nations (Praeger, 1980 ); and Mozam- bique: A History (Rex Collings, 1978). Additionally...taught history at the State University of New York from 1969, leaving in 1979 as a full professor. During the 1979- 1980 academic year, he was the Susan

  4. [Spectroscopic characteristics of novel Psidium meroterpenoids isolated from guava leaves].

    PubMed

    Ouyang, Wen; Zhu, Xiao-ai; Liu, Xiao-juan; Yie, Shu-min; Zhao, Litchao; Su, Lei; Cao, Yong

    2015-07-01

    Recently, novel Psidium meroterpenoids were reported in the guava leaves. According to careful analysis of the spectral data of literatures, the spectroscopic characteristics and biosynthetic pathway of Psidium meroterpenoids were summarized in this paper. The results showed that Psidium meroterpenoids had distinct spectroscopic features and reasonable biosynthetic routines, however the number order of carbon atoms was not consistent in the reported literatures. It was concluded that Psidium meroterpenoids were the characteristic chemical constituents of Psidium guajava Linn.

  5. Differential phenolic production in leaves of Vitis vinifera cv. Alvarinho affected with esca disease.

    PubMed

    Lima, Marta R M; Felgueiras, Mafalda L; Cunha, Ana; Chicau, Gisela; Ferreres, Federico; Dias, Alberto C P

    2017-03-01

    Esca is a destructive disease of complex etiology affecting grapevines worldwide. A major constraint to the study and control of esca is that the disease is not diagnosed until external leaf and/or fruit symptoms are visible; however external symptoms usually appear several years after infection onset. We studied the phenolic content of V. vinifera cv. Alvarinho leaves using high performance liquid chromatography-diode array detection-mass spectrometry (HPLC-DAD-MS)/LC-MS. Leaves from affected cordons with and without visible symptoms (diseased and apparently healthy leaves, respectively) and leaves from asymptomatic cordons (healthy leaves) were analyzed. Application of principal components analysis (PCA) to HPLC data showed a clear separation between diseased, apparently healthy, and healthy leaves, with the apparently healthy leaves clustered in a medial position. Several compounds were highly correlated with diseased leaves indicating a differential phenolic production due to esca disease in V. vinifera cv. Alvarinho leaves. Total phenolic production was shown to significantly increase in diseased leaves, compared to healthy leaves, with apparently healthy leaves containing a medial amount. Trans-caffeoyltartaric acid, trans-coumaroyl-tartaric acid, quercetin-3-O-glucoside, quercetin-3-O-galactoside, kaempferol-3-glucoside and myricetin were identified among the compounds associated with disease and their content shown to change similarly to total phenolic production. This study shows that it is possible to discriminate between diseased, healthy and apparently healthy leaves by applying PCA to HPLC data.

  6. Bioavailability of zinc from sweet potato roots and leaves

    SciTech Connect

    Baiden, H.N.; Ercanli-Huffman, F.G.

    1986-03-05

    Bioavailability of zinc from sweet potato (SP) roots and leaves were determined, by extrinsic labeling technique, in rats fed control and zinc deficient diets. Weanling male Sprague Dawley (SD) rats (60-75g) were divided into 4 groups, and fed laboratory chow, a control diet (ad libitum and pair fed) and a zinc deficient diet, for 4 weeks. Each group then was divided into at least 2 sub groups, containing 6 rats, which were intubated with one of 3 tubing solutions extrinsically labeled with /sup 65/Zn; baked sweet potato roots (BSPR), raw sweet potato leaves (RSPL) and cooked sweet potato leaves (CSPL). Five hours after intubation the rats were sacrificed, blood, liver, testes, spleen, heart, brain, thymus and lungs were removed. Feces, urine, and GI tract contents were collected and their /sup 65/Zn activity was determined in a gamma counter. In all treatment groups zinc bioavailability from BSPR, RSPL or CSPL were not significantly different. Zinc deficient rats absorbed significantly more (P < 0.01) /sup 65/Zn (86-90% of the dose), regardless of type of tubing solution than the pairfed or control animals (35-58% of the dose). The highest retention of /sup 65/Zn was found in the liver (12-20% of absorbed dose), GI tract (6-17% of absorbed dose), kidney (2-8% of absorbed dose), and blood (1-5% of absorbed dose). The lowest retention was found in the brain, heart, thymus and testes. (< 1% of absorbed dose).

  7. Air pollution effects on the structure of Citrus aurantium leaves

    SciTech Connect

    Psaras, G.K.; Christodoulakis, N.S.

    1987-09-01

    Individual air pollutants cause acute and chronic plant injury, act on stomata and affect carbon dioxide exchange as well as plant growth and development. Inhibition of photosynthesis by several air pollutants has been reported repeatedly. Besides, structural modifications of cell organelles have been reported after fumigation by SO/sub 2/. Although chlorosis and subsequent necrosis are common phenomena caused by artificial treatment with pollutants, fine structural leaf characteristics of plants exposed to long-term air pollution in natural conditions are little explored. Light microscope examination of air pollution affected leaves of plants common in natural ecosystems of Athens' metropolitan area revealed chlorosis phenomena. Electron microscope examination of the leaves of a common subshrub of greek phryganic formations grown in a heavily air polluted natural ecosystem of Athens metropolitan area revealed pronounced ultrastructural anomalies of chloroplasts, mitochondria and microbodies of the mesophyll cells. This organelle destruction of the photosynthesizing tissue as well as the minimization of the ecosystem primary productivity are attributed to the compound action of several toxic air pollutants of the photochemical smog of Athens. This work describes the long-term air pollution effects on the structural features of the leaves of Citrus aurantium, a decorative species planted throughout the heavily air polluted city of Athens.

  8. Kinetics of mass and DNA decomposition in tomato leaves.

    PubMed

    Poté, John; Rossé, Patrick; Rosselli, Walter; Van, Van Tran; Wildi, Walter

    2005-11-01

    This laboratory study investigated the kinetics of leaf and DNA content decomposition in two varieties of tomato (Palmiro and Admiro) after incubation in soil for 35 days. Results revealed that the decrease of dry matter in leaves in both varieties did not follow a single exponential function and was better described by a double exponential model. Composite half-decrease times were 3.4 and 2.4 days for Palmiro and Admiro respectively. The same pattern was observed for DNA mass loss, although this was closer to a single exponential model with composite half-decrease times of 1.5 and 1.4 days. Genomic analysis showed that DNA in dried leaves at room temperature (not inoculated in the soil), remains intact or presents a weak degradation, and DNA extracted from leaves inoculated in non-sterile soil showed degradation after two days. These results indicate that before release an important quantity of DNA may be degraded inside plant tissues during decomposition in soil.

  9. Characterization and subcellular localization of aminopeptidases in senescing barley leaves

    NASA Technical Reports Server (NTRS)

    Thayer, S. S.; Choe, H. T.; Rausser, S.; Huffaker, R. C.

    1988-01-01

    Four aminopeptidases (APs) were separated using native polyacrylamide gel electrophoresis of cell-free extracts and the stromal fractions of isolated chloroplasts prepared from primary barley (Hordeum vulgare L., var Numar) leaves. Activities were identified using a series of aminoacyl-beta-naphthylamide derivatives as substrates. AP1, 2, and 3 were found in the stromal fraction of isolated chloroplasts with respective molecular masses of 66.7, 56.5, and 54.6 kilodaltons. AP4 was found only in the cytoplasmic fraction. No AP activity was found in vacuoles of these leaves. It was found that 50% of the L-Leu-beta-naphthylamide and 25% of the L-Arg-beta-naphthylamide activities were localized in the chloroplasts. Several AP activities were associated with the membranes of the thylakoid fraction of isolated chloroplasts. AP1, 2, and 4 reacted against a broad range of substrates, whereas AP3 hydrolyzed only L-Arg-beta-naphthylamide. Only AP2 hydrolyzed L-Val-beta-naphthylamide. Since AP2 and AP3 were the only ones reacting against Val-beta-naphthylamide and Arg-beta-naphthylamide, respectively, several protease inhibitors were tested against these substrates using a stromal fraction from isolated chloroplasts as the source of the two APs. Both APs were sensitive to both metallo and sulfhydryl type inhibitors. Although AP activity decreased as leaves senesced, no new APs appeared on gels during senescence and none disappeared.

  10. Mechanical Stress Induces Remodeling of Vascular Networks in Growing Leaves.

    PubMed

    Bar-Sinai, Yohai; Julien, Jean-Daniel; Sharon, Eran; Armon, Shahaf; Nakayama, Naomi; Adda-Bedia, Mokhtar; Boudaoud, Arezki

    2016-04-01

    Differentiation into well-defined patterns and tissue growth are recognized as key processes in organismal development. However, it is unclear whether patterns are passively, homogeneously dilated by growth or whether they remodel during tissue expansion. Leaf vascular networks are well-fitted to investigate this issue, since leaves are approximately two-dimensional and grow manyfold in size. Here we study experimentally and computationally how vein patterns affect growth. We first model the growing vasculature as a network of viscoelastic rods and consider its response to external mechanical stress. We use the so-called texture tensor to quantify the local network geometry and reveal that growth is heterogeneous, resembling non-affine deformations in composite materials. We then apply mechanical forces to growing leaves after veins have differentiated, which respond by anisotropic growth and reorientation of the network in the direction of external stress. External mechanical stress appears to make growth more homogeneous, in contrast with the model with viscoelastic rods. However, we reconcile the model with experimental data by incorporating randomness in rod thickness and a threshold in the rod growth law, making the rods viscoelastoplastic. Altogether, we show that the higher stiffness of veins leads to their reorientation along external forces, along with a reduction in growth heterogeneity. This process may lead to the reinforcement of leaves against mechanical stress. More generally, our work contributes to a framework whereby growth and patterns are coordinated through the differences in mechanical properties between cell types.

  11. The absence of phloem loading in willow leaves

    PubMed Central

    Turgeon, Robert; Medville, Richard

    1998-01-01

    Willow (Salix babylonica L.) is representative of a large group of plants that have extensive plasmodesmatal connections between minor vein phloem and adjoining cells. Because plasmodesmata provide a diffusion pathway for small molecules, it is unclear how sucrose could be loaded from the mesophyll into the phloem against a concentration gradient. In the studies reported here, the minor vein phloem of willow leaves plasmolyzed in approximately the same concentration of osmoticum as the mesophyll. Sucrose concentrations in mesophyll cells were greater than those reported in the literature for aphid stylet exudate from willow stems. Calculated turgor pressures in the mesophyll and minor vein phloem were greater than turgor reported in the literature for sieve elements in the stems of willow. Images of minor veins were not obtained in autoradiographs when attached leaves, or leaf pieces, were provided with 14CO2 or [14C]sucrose. Therefore, no evidence could be found for accumulation of sucrose against a concentration gradient in the minor vein phloem of willow. In these leaves, the mesophyll apparently acts as the “source” for long distance transport of sugar. The mechanism of translocation in willow, and the evolution of phloem loading, are discussed. PMID:9751789

  12. Transcriptome response of cassava leaves under natural shade.

    PubMed

    Ding, Zehong; Zhang, Yang; Xiao, Yi; Liu, Fangfang; Wang, Minghui; Zhu, Xinguang; Liu, Peng; Sun, Qi; Wang, Wenquan; Peng, Ming; Brutnell, Tom; Li, Pinghua

    2016-08-19

    Cassava is an important staple crop in tropical and sub-tropical areas. As a common farming practice, cassava is usually cultivated intercropping with other crops and subjected to various degrees of shading, which causes reduced productivity. Herein, a comparative transcriptomic analysis was performed on a series of developmental cassava leaves under both full sunlight and natural shade conditions. Gene expression profiles of these two conditions exhibited similar developmental transitions, e.g. genes related to cell wall and basic cellular metabolism were highly expressed in immature leaves, genes involved in lipid metabolism and tetrapyrrole synthesis were highly expressed during the transition stages, and genes related to photosynthesis and carbohydrates metabolism were highly expressed in mature leaves. Compared with the control, shade significantly induced the expression of genes involved in light reaction of photosynthesis, light signaling and DNA synthesis/chromatin structure; however, the genes related to anthocyanins biosynthesis, heat shock, calvin cycle, glycolysis, TCA cycle, mitochondrial electron transport, and starch and sucrose metabolisms were dramatically depressed. Moreover, the shade also influenced the expression of hormone-related genes and transcriptional factors. The findings would improve our understanding of molecular mechanisms of shade response, and shed light on pathways associated with shade-avoidance syndrome for cassava improvement.

  13. New subtilisin-like collagenase from leaves of common plantain.

    PubMed

    Bogacheva, A M; Rudenskaya, G N; Dunaevsky, Y E; Chestuhina, G G; Golovkin, B N

    2001-06-01

    A new subtilisin-like proteinase hydrolyzing chromogenic peptide substrate Glp-Ala-Ala-Leu-p-nitroanilide optimally at pH 8.1 was found in common plantain leaves. The protease named plantagolisin was isolated by ammonium sulfate precipitation of the leaves' extract followed by affinity chromatography on bacitracin-Sepharose and ion-exchange chromatography on Mono Q in FPLC regime. Its molecular mass is 19000 Da and pI 5.0. pH-stability range is 7-10 in the presence of 2 mM Ca(2+), temperature optimum is 40 degrees C. The substrate specificity of subtilase towards synthetic peptides and insulin B-chain is comparable with that of two other subtilisin-like serine proteinases: proteinase from leaves of the sunflower and taraxalisin. Besides, the proteinase is able to hydrolyze substrates with Pro in P(1) position. The enzyme hydrolyzes collagen. alpha and beta chains are hydrolyzed simultaneously in parallel; there are only low-molecular-mass hydrolysis products in the sample after 2 h of incubation. Pure serine proteinase was inactivated by specific serine proteinases inhibitors: diisopropylfluorophosphate, phenylmethylsulfonyl fluoride and Hg(2+). The plantagolisin N-terminal sequence ESNSEQETQTESGPGTAFL-, traced for 19 residues, revealed 37% homology with that of subtilisin from yeast Schizosaccharomyces pombe.

  14. Evaluation of acute toxicity potential of water hyacinth leaves.

    PubMed

    Wu, Wenbiao; Guo, Xiaoguang; Huang, Mingliang

    2014-06-01

    Although higher protein yield per hectare of water hyacinth than that of soy, high protein content of its leaves and good essential amino acid pattern have been proven, its dietary toxicity for human or animal consumption has not yet been evaluated. Therefore, the acute toxicity of water hyacinth leaves has been evaluated by an animal feeding test. The concentrations of common toxic metals including cadmium, lead, platinum, palladium, tin, mercury, barium, silver, stibium and aluminum in the water hyacinth leaf powder (WHLP) used for the animal feeding test were within their maximum limits in food additives as reported by the World Health Organization. The median lethal dose (LD50) of WHLP was more than 16 g kg(-1) body weight. In the study, after feeding for 7 and 28 days, the body weight of all the mice increased. The results of hematological analysis, clinical biochemical analysis, histopathological evaluation, general dissection or investigations of internal organs, appearance and behavior observations did not indicate any adverse effects from the diet containing WHLP. It is therefore concluded that water hyacinth leaves are not acutely toxic.

  15. Leaving Buprenorphine Treatment: Patients’ Reasons for Cessation of Care

    PubMed Central

    Gryczynski, Jan; Mitchell, Shannon Gwin; Jaffe, Jerome H.; O’Grady, Kevin E.; Olsen, Yngvild K.; Schwartz, Robert P.

    2013-01-01

    Many opioid-dependent patients leave treatment prematurely. This study is a planned secondary analysis from a randomized trial of counseling for African Americans (N=297) entering buprenorphine treatment at one of two outpatient programs. This study examines: (1) whether patients’ initial treatment duration intentions prospectively predict retention; and (2) patients’ reasons for leaving treatment. Participants were queried about their treatment duration intentions at treatment entry, and their reasons for leaving treatment at 6-month follow-up. At baseline, 28.0% reported wanting to stay in buprenorphine treatment less than 6 months, while 42.1% actually left buprenorphine treatment within 6 months. However, participants intending short-term buprenorphine at the outset were not at elevated risk of early treatment discontinuation (OR=1.15; p=.65). Participants attributed treatment cessation predominantly to conflicts with staff, involuntary discharge, and perceived inflexibility of the program. Future research should examine patient-centered models of buprenorphine treatment that could improve retention. PMID:24238714

  16. Leaving from and returning to nursing practice: contributing factors.

    PubMed

    Jamieson, Isabel; Taua, Chris

    2009-07-01

    Many nurses leave nursing and never return. Others return after a period of time. Given the global shortage of nurses a better understanding of these movements is needed. The present study focused on nurses who had been out of nursing for more than five years, and explored factors that influenced their leaving and return to practice. All the nurses who had undertaken a Competency Assessment Programme at a given New Zealand tertiary institution during 2005 were invited to participate. Of the 70 questionnaires mailed out 32 (44.5%) were completed and returned. Quantitative data were analysed using Microsoft Excel, and the qualitative data were coded and analysed by means of content analysis. For each, leaving and returning, three key issues emerged. Nurses left for personal reasons, to seek a career change, or because of poor working conditions. They returned when they had the personal freedom to do so, for fiscal reasons, or because they were motivated by some sense of unfinished business. These findings indicate that it is important for educators involved with Competency Assessment Programmes to collaborate with employers in ensuring that there are opportunities for re-entry to positive work environments, with a degree of flexibility that suits the demographic characteristics of those nurses returning to practice.

  17. Pathway of phloem unloading in tobacco sink leaves. [Nicotiana tabacum

    SciTech Connect

    Turgeon, R.

    1987-04-01

    Phloem unloading in transition sink leaves of tobacco (Nicotiana tabacum L.) was analyzed by quantitative autoradiography. Source leaves were labeled with /sup 14/CO/sub 2/ and experimental treatments were begun approximately 1 h later when label had entered the sink leaves. Autoradiographs were prepared from rapidly frozen, lyophilized sink tissue at the beginning and end of the treatments and the amount of label in veins and in surrounding cells was determined by microdensitometry. Photoassimilate unloaded from third order and larger, but not smaller, veins. Long-distance import and unloading did not respond the same way to all experimental treatments. Import was completely inhibited by cold, anaerobiosis or steam girdling the sink leaf petiole. Unloading was inhibited by cold but continued in an anaerobic atmosphere and after steam girdling. Uptake of exogenous (/sup 14/C)sucrose was inhibited by anaerobiosis. Since an apoplastic pathway of phloem unloading would involve solute uptake from the apoplast the results are most consistent with passive symplastic unloading of photoassimilates from phloem to surrounding cells.

  18. An Assessment of Wound Healing Potential of Argyreia speciosa Leaves

    PubMed Central

    Yadav, Narayan Prasad; Rawat, Bindu; Rai, Vineet Kumar; Shanker, Karuna; Venkateswara Rao, Chandana

    2014-01-01

    In North India, poultice of young unfolded leaves of Argyreia speciosa Linn. (Convolvulaceae) is used for healing wounds. In order to find scientific evidence for the traditional utilization of leaves of A. speciosa in wound healing, this investigation was carried out. A linear incision wound of about 3 cm in length and 2 mm in depth and circular excision wound of 177 mm2 full thickness were made on the dorsal region of separate groups (n = 5) of anesthetized Swiss albino mice. A simple ointment, developed by including ethanol, ethanol-water, and water extracts (10% each, separately) of A. speciosa, was applied topically to mice once daily for 14 days after wounding. To evaluate the effect of each extract, wound contraction, epithelization period, wound breaking strength, and hydroxyproline content were determined. The water extract of A. speciosa showed accelerated wound healing activity as evidenced by fast wound contraction (96.30 ± 0.52%; P < 0.01), rapid epithelization period (11.40 ± 0.60 days; P < 0.001), greater wound breaking strength (376.56 ± 21.16 g; P < 0.001), and higher hydroxyproline content (16.49 ± 1.12 mg/g; P < 0.05) of granulation tissue. The present report supports the traditional use of Argyreia speciosa leaves for wound healing and signify its relevant therapeutic potential. PMID:24688387

  19. Transcriptome response of cassava leaves under natural shade

    PubMed Central

    Ding, Zehong; Zhang, Yang; Xiao, Yi; Liu, Fangfang; Wang, Minghui; Zhu, Xinguang; Liu, Peng; Sun, Qi; Wang, Wenquan; Peng, Ming; Brutnell, Tom; Li, Pinghua

    2016-01-01

    Cassava is an important staple crop in tropical and sub-tropical areas. As a common farming practice, cassava is usually cultivated intercropping with other crops and subjected to various degrees of shading, which causes reduced productivity. Herein, a comparative transcriptomic analysis was performed on a series of developmental cassava leaves under both full sunlight and natural shade conditions. Gene expression profiles of these two conditions exhibited similar developmental transitions, e.g. genes related to cell wall and basic cellular metabolism were highly expressed in immature leaves, genes involved in lipid metabolism and tetrapyrrole synthesis were highly expressed during the transition stages, and genes related to photosynthesis and carbohydrates metabolism were highly expressed in mature leaves. Compared with the control, shade significantly induced the expression of genes involved in light reaction of photosynthesis, light signaling and DNA synthesis/chromatin structure; however, the genes related to anthocyanins biosynthesis, heat shock, calvin cycle, glycolysis, TCA cycle, mitochondrial electron transport, and starch and sucrose metabolisms were dramatically depressed. Moreover, the shade also influenced the expression of hormone-related genes and transcriptional factors. The findings would improve our understanding of molecular mechanisms of shade response, and shed light on pathways associated with shade-avoidance syndrome for cassava improvement. PMID:27539510

  20. Polarization of Light by Leaves and Plant Canopies

    NASA Technical Reports Server (NTRS)

    Vanderbilt, V. C.

    2006-01-01

    This talk will focus first on the information contained in the surface-scattered light from leaves, plant canopies and surface waters. This light is in general polarized and depends upon surface roughness. Thus, for example, - The surface reflection from shiny green leaves measured in the specular direction shows no chlorophyll absorption bands, no 'red edge.' - Conversely, the degree of linear polarization of such light displays marked variation with wavelength having local maxima in the chlorophyll absorption bands and an inverted red edge. - Plant canopies with shiny leaves distributed in angle like the area on a sphere, specularly reflect sunlight in the subsolar or specular direction- but also in every other view direction. - Canopies of green plants may appear white not green when viewed obliquely toward the sun. - In a light to moderate wind, the often blindingly bright glitter of sunlight off smooth water surfaces provides a strong, angularly narrow signature reflection characteristic of inundated vegetated areas that are big sources of atmospheric methane, a climatically important greenhouse gas. (Conversely, a blindingly bright glitter-type reflection is uncharacteristic of upland or wind ruffled open water areas that are poor sources of atmospheric methane.) Because some of these results may be 'head scratchers,' it's always important to properly calibrate ones instruments. Indeed, as the second portion of the talk will show, the characteristics of the light measuring instrument, particularly its entrance aperture, may affect the results and should be taken into account during across-instrument data comparisons.

  1. Photosynthetic quantum yield dynamics: from photosystems to leaves.

    PubMed

    Hogewoning, Sander W; Wientjes, Emilie; Douwstra, Peter; Trouwborst, Govert; van Ieperen, Wim; Croce, Roberta; Harbinson, Jeremy

    2012-05-01

    The mechanisms underlying the wavelength dependence of the quantum yield for CO(2) fixation (α) and its acclimation to the growth-light spectrum are quantitatively addressed, combining in vivo physiological and in vitro molecular methods. Cucumber (Cucumis sativus) was grown under an artificial sunlight spectrum, shade light spectrum, and blue light, and the quantum yield for photosystem I (PSI) and photosystem II (PSII) electron transport and α were simultaneously measured in vivo at 20 different wavelengths. The wavelength dependence of the photosystem excitation balance was calculated from both these in vivo data and in vitro from the photosystem composition and spectroscopic properties. Measuring wavelengths overexciting PSI produced a higher α for leaves grown under the shade light spectrum (i.e., PSI light), whereas wavelengths overexciting PSII produced a higher α for the sun and blue leaves. The shade spectrum produced the lowest PSI:PSII ratio. The photosystem excitation balance calculated from both in vivo and in vitro data was substantially similar and was shown to determine α at those wavelengths where absorption by carotenoids and nonphotosynthetic pigments is insignificant (i.e., >580 nm). We show quantitatively that leaves acclimate their photosystem composition to their growth light spectrum and how this changes the wavelength dependence of the photosystem excitation balance and quantum yield for CO(2) fixation. This also proves that combining different wavelengths can enhance quantum yields substantially.

  2. Inhibition of rat platelet aggregation by Urtica dioica leaves extracts.

    PubMed

    El Haouari, Mohammed; Bnouham, Mohamed; Bendahou, Mourad; Aziz, Mohammed; Ziyyat, Abderrahim; Legssyer, Abdelkhaleq; Mekhfi, Hassane

    2006-07-01

    Platelet hyperactivity plays an important role in arterial thrombosis and atherosclerosis. The present study was undertaken to investigate the effects of different extracts of Urtica dioica leaves on platelet aggregation. Rat platelets were prepared and incubated in vitro with different concentrations of the tested extracts and aggregation was induced by different agonists including thrombin (0.5 U/mL), ADP (10 microm), epinephrine (100 microm) and collagen (5 mg/mL). The crude aqueous extract inhibited thrombin-induced platelet aggregation in a dose-dependent manner. At 1 mg/mL, the percent inhibition was 17.1 +/- 4.2%. Soxhlet extraction of the plant leaves with different successive solvents showed that the ethyl acetate extract exhibited the most antiaggregant effect with an inhibition of 76.8 +/- 6.1% at 1 mg/mL. Flavonoids isolated from the plant leaves, produced a strong inhibitory effect on thrombin-induced platelet aggregation with an IC(50) of 0.25 +/- 0.05 and 0.40 +/- 0.04 mg/mL for genins and heterosidic flavonoids, respectively. Flavonoids also markedly inhibited platelet aggregation induced by ADP, collagen and epinephrine. It is concluded that Urtica dioica has an antiplatelet action in which flavonoids are mainly implicated. These results support the traditional use of Urtica dioica in the treatment and/or prevention of cardiovascular disease.

  3. Zinc deficiency affects physiological and anatomical characteristics in maize leaves.

    PubMed

    Mattiello, Edson M; Ruiz, Hugo A; Neves, Julio C L; Ventrella, Marília C; Araújo, Wagner L

    2015-07-01

    Zinc (Zn) is an essential microelement involved in several plant physiological processes. Therefore, it is important to identify Zn deficiencies promptly--before extensive damage occurs to the plant. The diagnostic tools that are used to identify Zn deficiencies are very important in areas where Zn deficiencies occur. Such diagnostic tools are vital for nutritional management and fertilizer recommendations. The current study investigated the effects of Zn deficiency on maize plants by recording a number of physiological and anatomical parameters. A Zn omission trial (from 0 to 22 days) was carried out to produce plants that had varying degrees of Zn deficiency. Typical symptoms of Zn deficiency (e.g. chlorotic stripes and purple shades on the edges and leaf sheath) appeared 16 days after the omission of Zn from nutrient solutions. As the time of Zn omission increased, there were significant decreases in net photosynthesis, stomatal conductance, maximal efficiency of photosystem I (evaluated by Fv/Fm), biomass (dry weight) and Zn concentrations in plants. Zinc-deficient plants also had a lower vascular bundle proportion coupled with a higher stomata density. These physiological and anatomical changes negatively impacted plant growth. Moreover, they occurred before visible symptoms of Zn deficiency were observed. Zinc concentrations were recorded for younger leaves, rather than for more mature leaves, which is usually recommended for plant analysis. The results demonstrate that the analysis of Zn in young leaves of maize is a very sensitive indicator of Zn status.

  4. Separation and identification of major plant sphingolipid classes from leaves.

    PubMed

    Markham, Jonathan E; Li, Jia; Cahoon, Edgar B; Jaworski, Jan G

    2006-08-11

    Sphingolipids are major components of the plasma membrane, tonoplast, and other endomembranes of plant cells. Previous compositional analyses have focused only on individual sphingolipid classes because of the widely differing polarities of plant sphingolipids. Consequently, the total content of sphingolipid classes in plants has yet to be quantified. In addition, the major polar sphingolipid class in the model plant Arabidopsis thaliana has not been previously determined. In this report, we describe the separation and quantification of sphingolipid classes from A. thaliana leaves using hydrolysis of sphingolipids and high performance liquid chromatography (HPLC) analysis of o-phthaldialdehyde derivatives of the released long-chain bases to monitor the separation steps. An extraction solvent that contained substantial proportions of water was used to solubilized >95% of the sphingolipids from leaves. Neutral and charged sphingolipids were then partitioned by anion exchange solid phase extraction. HPLC analysis of the charged lipid fraction from A. thaliana revealed only one major anionic sphingolipid class, which was identified by mass spectrometry as hexose-hexuronic-inositolphosphoceramide. The neutral sphingolipids were predominantly composed of monohexosylceramide with lesser amounts of ceramides. Extraction and separation of sphingolipids from soybean and tomato showed that, like A. thaliana, the neutral sphingolipids consisted of ceramide and monohexosylceramides; however, the major polar sphingolipid was found to be N-acetyl-hexosamine-hexuronic-inositolphosphoceramide. In extracts from A. thaliana leaves, hexosehexuronic-inositolphosphoceramides, monohexosylceramides, and ceramides accounted for approximately 64, 34, and 2% of the total sphingolipids, respectively, suggesting an important role for the anionic sphingolipids in plant membranes.

  5. Mechanical Stress Induces Remodeling of Vascular Networks in Growing Leaves

    PubMed Central

    Bar-Sinai, Yohai; Julien, Jean-Daniel; Sharon, Eran; Armon, Shahaf; Nakayama, Naomi; Adda-Bedia, Mokhtar; Boudaoud, Arezki

    2016-01-01

    Differentiation into well-defined patterns and tissue growth are recognized as key processes in organismal development. However, it is unclear whether patterns are passively, homogeneously dilated by growth or whether they remodel during tissue expansion. Leaf vascular networks are well-fitted to investigate this issue, since leaves are approximately two-dimensional and grow manyfold in size. Here we study experimentally and computationally how vein patterns affect growth. We first model the growing vasculature as a network of viscoelastic rods and consider its response to external mechanical stress. We use the so-called texture tensor to quantify the local network geometry and reveal that growth is heterogeneous, resembling non-affine deformations in composite materials. We then apply mechanical forces to growing leaves after veins have differentiated, which respond by anisotropic growth and reorientation of the network in the direction of external stress. External mechanical stress appears to make growth more homogeneous, in contrast with the model with viscoelastic rods. However, we reconcile the model with experimental data by incorporating randomness in rod thickness and a threshold in the rod growth law, making the rods viscoelastoplastic. Altogether, we show that the higher stiffness of veins leads to their reorientation along external forces, along with a reduction in growth heterogeneity. This process may lead to the reinforcement of leaves against mechanical stress. More generally, our work contributes to a framework whereby growth and patterns are coordinated through the differences in mechanical properties between cell types. PMID:27074136

  6. Characteristics of opiate users leaving detoxification treatment against medical advice.

    PubMed

    Kenne, Deric R; Boros, Alec P; Fischbein, Rebecca L

    2010-07-01

    Substance-dependent patients leaving against medical advice (AMA) pose a unique challenge to detoxification programs. Most notably, AMA patients fail to access residential or outpatient treatment needed after detoxification and often return to detoxification treatment multiple times which has deleterious results for the patient and is taxing to the healthcare system. Using retrospective data from 89 daily opiate-using detoxification patients completing detoxification and 95 patients leaving AMA, we sought to identify patient characteristics useful in predicting AMA discharges from detoxification. Bivariate analyses indicated that AMA patients reported drug use did not impair their health, were injection drug users, younger and had fewer previous treatment admissions. Binomial logistic regression indicated that AMA patients were more likely to be unemployed and report that drug use did not impair their health. Patients completing detoxification were less likely to be injection drug users and less likely to be self-referred to treatment. Identifying patients at risk of leaving AMA provides an opportunity for clinicians to intervene in an effort to increase treatment engagement for these patients.

  7. Radioactivity of Tobacco Leaves and Radiation Dose Induced from Smoking

    PubMed Central

    Papastefanou, Constantin

    2009-01-01

    The radioactivity in tobacco leaves collected from 15 different regions of Greece and before cigarette production was studied in order to find out any association between the root uptake of radionuclides from soil ground by the tobacco plants and the effective dose induced to smokers from cigarette tobacco due to the naturally occurring primordial radionuclides, such as 226Ra and 210Pb of the uranium series and 228Ra of the thorium series and/or man-made radionuclides, such as 137Cs of Chernobyl origin. Gamma-ray spectrometry was applied using Ge planar and coaxial type detectors of high resolution and high efficiency. It was concluded that the activities of the radioisotopes of radium, 226Ra and 228Ra in the tobacco leaves reflected their origin from the soil by root uptake rather than fertilizers used in the cultivation of tobacco plants. Lead-210 originated from the air and was deposited onto the tobacco leaves and trapped by the trichomes. Potassium-40 in the tobacco leaves was due to root uptake either from soil or from fertilizer. The cesium radioisotopes 137Cs and 134Cs in tobacco leaves were due to root uptake and not due to deposition onto the leaf foliage as they still remained in soil four years after the Chernobyl reactor accident, but were absent from the atmosphere because of the rain washout (precipitation) and gravitational settling. The annual effective dose due to inhalation for adults (smokers) for 226Ra varied from 42.5 to 178.6 μSv/y (average 79.7 μSv/y), while for 228Ra from 19.3 to 116.0 μSv/y (average 67.1 μSv/y) and for 210Pb from 47.0 to 134.9 μSv/y (average 104.7 μSv/y), that is the same order of magnitude for each radionuclide. The sum of the effective doses of the three radionuclides varied from 151.9 to 401.3 μSv/y (average 251.5 μSv/y). The annual effective dose from 137Cs of Chernobyl origin was three orders of magnitude lower as it varied from 70.4 to 410.4 nSv/y (average 199.3 nSv/y). PMID:19440399

  8. Tracking synthesis and turnover of triacylglycerol in leaves

    SciTech Connect

    Tjellstrom, Henrik; Strawsine, Merissa; Ohlrogge, John B.

    2015-01-21

    Triacylglycerol (TAG), typically represents <1% of leaf glycerolipids but can accumulate under stress and other conditions or if leaves are supplied with fatty acids, or in plants transformed with regulators or enzymes of lipid metabolism. To better understand the metabolism of TAG in leaves, pulse-chase radiolabelling experiments were designed to probe its synthesis and turnover. When Arabidopsis leaves were incubated with [14C]lauric acid (12:0), a major initial product was [14C]TAG. Thus, despite low steady-state levels, leaves possess substantial TAG biosynthetic capacity. The contributions of diacylglycerol acyltransferase1 and phospholipid:diacylglycerol acyltransferase1 to leaf TAG synthesis were examined by labelling of dgat1 and pdat1 mutants. The dgat1 mutant displayed a major (76%) reduction in [14C]TAG accumulation whereas pdat1 TAG labelling was only slightly reduced. Thus, DGAT1 has a principal role in TAG biosynthesis in young leaves. During a 4h chase period, radioactivity in TAG declined 70%, whereas the turnover of [14C]acyl chains of phosphatidylcholine (PC) and other polar lipids was much lower. Sixty percent of [14C]12:0 was directly incorporated into glycerolipids without modification, whereas 40% was elongated and desaturated to 16:0 and 18:1 by plastids. The unmodified [14C]12:0 and the plastid products of [14C]12:0 metabolism entered different pathways. Although plastid-modified 14C-labelled products accumulated in monogalactosyldiacylglycerol, PC, phosphatidylethanolamine, and diacylglcerol (DAG), there was almost no accumulation of [14C]16:0 and [14C]18:1 in TAG. Lastly, because DAG and acyl-CoA are direct precursors of TAG, the differential labelling of polar glycerolipids and TAG by [14C]12:0 and its plastid-modified products provides evidence for multiple subcellular pools of both acyl-CoA and DAG.

  9. Fluorescence parameters of leaves of trees and shrubs during period of adverse weather conditions in Krasnoyarsk

    NASA Astrophysics Data System (ADS)

    Zavorueva, E. N.; Zavoruev, V. V.

    2015-11-01

    The effect of adverse weather conditions (AWC) on the fluorescence parameters of leaves Prinsepia sinensis, Amelanchier florida, Crataegus chlorocarca is obtained. However, significant changes in the fluorescence of the leaves of Acer negundo, Betula pendula under AWC were not observed.

  10. Should I stay or should I go? The impact of age norms on leaving home.

    PubMed

    Billari, Francesco C; Liefbroer, Aart C

    2007-02-01

    This article studies the association between social norms and the timing of leaving home. Although largely overlooked by most recent studies on leaving home, life-course theory suggests that age norms and age grading influence life-course decisions in general and leaving home in particular. We use Fishbein and Ajzen's model of "reasoned behavior" to integrate this strand of research with the more individualistic view that dominates current thinking. Using data from a Dutch panel survey, we use a Cox regression model with a control for sample selection to estimate the association between perceived age norms and the timing of leaving home. We show that perceived opinions of parents are associated with the actual timing of leaving the parental home but that societal norms and friends' norms concerning the timing of leaving home are not. In addition, the timing of leaving home is also associated with the perceived costs and benefits of leaving home and with the perceived housing market situation.

  11. [Sick leave benefits for workers in the Brazilian meat and fish industries in 2008].

    PubMed

    Jakobi, Heinz Roland; Barbosa-Branco, Anadergh; Bueno, Luis Fernando; Ferreira, Ricardo de Godoi Mattos; Camargo, Luís Marcelo Aranha

    2015-01-01

    This study aims to analyze factors associated with sick leave rates among workers in the meat, fish, and seafood industries in Brazil. The study analyzed all sick leave benefits granted by the country's social security system to workers in these industries in 2008. Incidence of sick leave per 10 thousand jobs was stratified by sex, age, diagnosis, job position, State, and nature and length of benefits. The study analyzed 31,913 sick leaves, with an annual incidence of 788.7. Meat processing and packaging showed the highest incidence, and fish and seafood processing and packaging showed the longest mean length of sick leave. Women showed a higher sick leave incidence, while men received longer average sick leaves. Injuries, musculoskeletal disorders, and mental disorders accounted for 67.2% of sick leaves. The most common diagnoses were lower back pain, first-trimester bleeding in pregnancy, and depression. The data suggest poor job protection and adverse working conditions in these industries.

  12. Influence of harvest season on antioxidant activity and constituents of rabbiteye blueberry ( Vaccinium ashei ) leaves.

    PubMed

    Zhu, Liancai; Liu, Xi; Tan, Jun; Wang, Bochu

    2013-11-27

    To select rabbiteye blueberry leaves from an appropriate harvest season to develop functional foods, this paper studied the bioactive secondary metabolites and the antioxidant capacity of rabbiteye blueberry leaves from May, September, and November. The results showed the leaves from May had the highest content of total flavonoids (114.21 mg/g) and the leaves from November had the highest content of total polyphenols and proanthocyanidins (425.24 and 243.29 mg/g, respectively). It was further found that blueberry leaves from different seasons have similar bioactive constituents, but their contents are obviously different by HPLC. The rabbiteye blueberry leaves from November had the highest antioxidant capacity, which was well correlated with their highest proanthocyanidin content. The results clarify that the blueberry leaves from different seasons have different contents of bioactive secondary metabolites and different antioxidant activities, which implied that leaves from November should be selected first for utilization in functional foods.

  13. 29 CFR 825.309 - Certification for leave taken because of a qualifying exigency.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee and Employer Rights and Obligations Under the Act § 825.309 Certification for leave taken because of a qualifying exigency. (a)...

  14. 29 CFR 825.309 - Certification for leave taken because of a qualifying exigency.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee and Employer Rights and Obligations Under the Act § 825.309 Certification for leave taken because of a qualifying exigency. (a)...

  15. 29 CFR 825.309 - Certification for leave taken because of a qualifying exigency.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee and Employer Rights and Obligations Under the Act § 825.309 Certification for leave taken because of a qualifying exigency. (a)...

  16. 29 CFR 825.309 - Certification for leave taken because of a qualifying exigency.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee and Employer Rights and Obligations Under the Act § 825.309 Certification for leave taken because of a qualifying exigency. (a)...

  17. Comparing FAPAR by canopy, FAPAR by leaves, FAPAR by chlorophyll in leaves, NDVI, and EVI of Harvard Forest using MODIS data

    NASA Astrophysics Data System (ADS)

    Zhang, Q.; Xiao, X.; Braswell, B.; Aber, J.; Moore, B.

    2004-12-01

    Moderate Resolution Imaging Spectroradiometer (MODIS) provides an improved potential (more and finer spectral bands, and finer spatial resolution) for better characteristics of vegetation at global scale than AVHRR (advanced very high resolution radiometer). We calculated fraction of photosynthetically active radiation (PAR) absorbed (FAPAR) by canopy, by leaves, and by chlorophyll in leaves of Harvard Forest using the PROSPECT+SAIL (PROSAIL) model and MODIS daily data. The FAPAR by canopy, FAPAR by leaves, FAPAR by chlorophyll in leaves,normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) from the same MODIS daily data were compared. We concluded that, under atmospherically clear condition for Harvard Forest, EVI is closer to FAPAR by chlorophyll in leaves than other two FAPAR, and NDVI is closer to FAPAR by leaves than other two FAPAR, at the MODIS scale ( about 500m). We plan to investigate their relationships under both atmospherically polluted condition and atmospherically clear condition and for other forest sites in the future.

  18. Longevity of guard cell chloroplasts in falling leaves: implication for stomatal function and cellular aging

    SciTech Connect

    Zeiger, E.; Schwartz, A.

    1982-11-12

    Guard cell chloroplasts in senescing leaves from 12 species of perennial trees and three species of annual plants survived considerably longer than their mesophyll counterparts. In Ginkgo biloba, stomata from yellow leaves opened during the day and closed at night; guard cell chloroplasts from these leaves showed fluorescence transients associated with electron transport and photophosphorylation. These findings indicate that guard cell chloroplasts are highly conserved throughout the life-span of the leaf and that leaves retain stomatal control during senescence.

  19. Quantitation of chafurosides A and B in tea leaves and isolation of prechafurosides A and B from oolong tea leaves.

    PubMed

    Ishida, Hitoshi; Wakimoto, Toshiyuki; Kitao, Yukiko; Tanaka, Shimako; Miyase, Toshio; Nukaya, Haruo

    2009-08-12

    A procedure was developed for the quantitative determination of chafuroside A, a flavone C-glycoside with potent anti-inflammatory activity, and its regioisomer chafuroside B, as well as isovitexin and vitexin, by selected reaction monitoring liquid chromatography-tandem mass spectrometry (SRM LC-MS/MS) analysis. This method was successfully applied to commercial leaves of green tea, houji tea, oolong tea, and black tea. High levels of chafurosides A and B were found in oolong tea leaves that had been heated at >140 degrees C. Next, their precursors, prechafurosides A and B, were isolated from methanol extract of oolong tea leaves prepared from Shizu 7132, Camellia sinensis (L.) O. Kuntze, by partition with n-butanol and H2O and chromatography on Diaion SP-825, Sephadex LH-20, and ODS C-18, guided by assay of chafuroside formation. Prechafurosides A and B gave chafurosides A and B, respectively, in good yields when heated at 160 degrees C for 0.5 h. Solvolysis of prechafurosides A and B with pyridine and dioxane quantitatively afforded isovitexin and vitexin, respectively. On the basis of these results and physicochemical data (MS, UV, and NMR), prechafurosides A and B were concluded to be new flavone C-glycoside sulfates, isovitexin-2''-sulfate and vitexin-2''-sulfate, respectively.

  20. Tri-Trophic Insecticidal Effects of African Plants against Cabbage Pests

    PubMed Central

    Amoabeng, Blankson W.; Gurr, Geoff M.; Gitau, Catherine W.; Nicol, Helen I.; Stevenson, Phil C.

    2013-01-01

    Botanical insecticides are increasingly attracting research attention as they offer novel modes of action that may provide effective control of pests that have already developed resistance to conventional insecticides. They potentially offer cost-effective pest control to smallholder farmers in developing countries if highly active extracts can be prepared simply from readily available plants. Field cage and open field experiments were conducted to evaluate the insecticidal potential of nine common Ghanaian plants: goat weed, Ageratum conyzoides (Asteraceae), Siam weed, Chromolaena odorata (Asteraceae), Cinderella weed, Synedrella nodiflora (Asteraceae), chili pepper, Capsicum frutescens (Solanaceae), tobacco, Nicotiana tabacum (Solanaceae) cassia, Cassia sophera (Leguminosae), physic nut, Jatropha curcas (Euphorbiaceae), castor oil plant, Ricinus communis (Euphorbiaceae) and basil, Ocimum gratissimum (Lamiaceae). In field cage experiments, simple detergent and water extracts of all botanical treatments gave control of cabbage aphid, Brevicoryne brassicae and diamondback moth, Plutella xylostella, equivalent to the synthetic insecticide Attack® (emamectin benzoate) and superior to water or detergent solution. In open field experiments in the major and minor rainy seasons using a sub-set of plant extracts (A. conyzoides, C. odorata, S. nodiflora, N. tabacum and R. communis), all controlled B. brassicae and P. xylostella more effectively than water control and comparably with or better than Attack®. Botanical and water control treatments were more benign to third trophic level predators than Attack®. Effects cascaded to the first trophic level with all botanical treatments giving cabbage head weights, comparable to Attack® in the minor season. In the major season, R. communis and A conyzoides treatment gave lower head yields than Attack® but the remaining botanicals were equivalent or superior to this synthetic insecticide. Simply-prepared extracts from readily

  1. The correlation of the maximum intensity of fluorescence with pigment characteristics of leaves of Betula pendula

    NASA Astrophysics Data System (ADS)

    Zavoruev, V. V.; Zavorueva, E. N.

    2015-11-01

    Using fluorimeter Junior PAM (Heinz Walz GmbH, Germany) the fluorescence parameters of leaves of Betula pendula are investigated. A linear dependence of the maximum fluorescence (Fm) of leaves from the ratio of total chlorophylls concentration to concentration of carotenoids is obtained. Such dependence is found for samples collected during the period of vegetation and for simultaneous selection of colored leaves.

  2. Detection of honey mesquite leaves in cattle diets using fecal near infrared reflectance spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Honey mesquite (Prosopis glandulosa Torr.) is a common invasive shrub whose leaves contain secondary compounds that limit consumption by cattle. However, crude protein and fiber levels of mesquite leaves are similar to alfalfa hay. The ability to consume small quantities of mesquite leaves might mak...

  3. 29 CFR 825.121 - Leave for adoption or foster care.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Leave for adoption or foster care. 825.121 Section 825.121... Leave for adoption or foster care. (a) General rules. Eligible employees are entitled to FMLA leave for placement with the employee of a son or daughter for adoption or foster care as follows: (1) Employees...

  4. 29 CFR 825.121 - Leave for adoption or foster care.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Leave for adoption or foster care. 825.121 Section 825.121... Leave for adoption or foster care. (a) General rules. Eligible employees are entitled to FMLA leave for placement with the employee of a son or daughter for adoption or foster care as follows: (1) Employees...

  5. 29 CFR 825.121 - Leave for adoption or foster care.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Leave for adoption or foster care. 825.121 Section 825.121... Leave for adoption or foster care. (a) General rules. Eligible employees are entitled to FMLA leave for placement with the employee of a son or daughter for adoption or foster care as follows: (1) Employees...

  6. 29 CFR 825.121 - Leave for adoption or foster care.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Leave for adoption or foster care. 825.121 Section 825.121... Leave for adoption or foster care. (a) General rules. Eligible employees are entitled to FMLA leave for placement with the employee of a son or daughter for adoption or foster care as follows: (1) Employees...

  7. 29 CFR 825.121 - Leave for adoption or foster care.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Leave for adoption or foster care. 825.121 Section 825.121... Leave for adoption or foster care. (a) General rules. Eligible employees are entitled to FMLA leave for placement with the employee of a son or daughter for adoption or foster care as follows: (1) Employees...

  8. Evidence from Maternity Leave Expansions of the Impact of Maternal Care on Early Child Development

    ERIC Educational Resources Information Center

    Baker, Michael; Milligan, Kevin

    2010-01-01

    We study the impact of maternal care on early child development using an expansion in Canadian maternity leave entitlements. Following the leave expansion, mothers who took leave spent 48-58 percent more time not working in their children's first year of life. This extra maternal care primarily crowded out home-based care by unlicensed…

  9. 29 CFR 825.302 - Employee notice requirements for foreseeable FMLA leave.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee and Employer Rights and Obligations Under the Act § 825.302 Employee notice requirements for foreseeable FMLA leave. (a) Timing of... further to determine for which qualifying reason the leave is needed. An employee has an obligation...

  10. A Report on the Status of Sabbatical Leaves for Administrators in California Junior Colleges.

    ERIC Educational Resources Information Center

    Bandley, Marion K.

    This recent study investigates sabbatical leave policy for administrators in 80 California Junior Colleges. Except for a few newly-formed colleges or those having boards generally unfavorable to the idea, most of the colleges responding to the survey indicated some type of policy for granting such leaves. Justification for these leaves ranges from…

  11. 29 CFR 825.112 - Qualifying reasons for leave, general rule.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Coverage Under the Family and Medical Leave Act...'s spouse, son, daughter, or parent is a military member on covered active duty (or has been notified... well as a mother, can take family leave for the birth, placement for adoption, or foster care of...

  12. 29 CFR 825.112 - Qualifying reasons for leave, general rule.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... employees. A father, as well as a mother, can take family leave for the birth, placement for adoption, or... OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Coverage Under the Family and Medical Leave Act...'s spouse, son, daughter, or parent is a covered military member on active duty (or has been...

  13. 29 CFR 825.112 - Qualifying reasons for leave, general rule.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... well as a mother, can take family leave for the birth, placement for adoption, or foster care of a... OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Coverage Under the Family and Medical Leave Act...'s spouse, son, daughter, or parent is a military member on covered active duty (or has been...

  14. 29 CFR 825.112 - Qualifying reasons for leave, general rule.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... employees. A father, as well as a mother, can take family leave for the birth, placement for adoption, or... OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Coverage Under the Family and Medical Leave Act...'s spouse, son, daughter, or parent is a covered military member on active duty (or has been...

  15. 29 CFR 825.112 - Qualifying reasons for leave, general rule.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... employees. A father, as well as a mother, can take family leave for the birth, placement for adoption, or... OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Coverage Under the Family and Medical Leave Act...'s spouse, son, daughter, or parent is a covered military member on active duty (or has been...

  16. Moderate Photoinhibition of Photosystem II Protects Photosystem I from Photodamage at Chilling Stress in Tobacco Leaves

    PubMed Central

    Huang, Wei; Yang, Ying-Jie; Hu, Hong; Zhang, Shi-Bao

    2016-01-01

    It has been indicated that photosystem I (PSI) is susceptible to chilling-light stress in tobacco leaves, but the effect of growth light intensity on chilling-induced PSI photoinhibition in tobacco is unclear. We examined the effects of chilling temperature (4°C) associated with moderate light intensity (300 μmol photons m-2 s-1) on the activities of PSI and photosystem II (PSII) in leaves from sun- and shade-grown plants of tobacco (Nicotiana tabacum cv. k326). The sun leaves had a higher activity of alternative electron flow than the shade leaves. After 4 h chilling treatment, the sun leaves showed significantly a higher PSI photoinhibition than the shade leaves. At chilling temperature the sun leaves showed a greater electron flow from PSII to PSI, accompanying with a lower P700 oxidation ratio. When leaves were pre-treated with lincomycin, PSII activity decreased by 42% (sun leaves) and 47% (shade leaves) after 2 h exposure to the chilling-light stress, but PSI activity remained stable during the chilling-light treatment, because the electron flow from PSII to PSI was remarkably depressed. These results indicated that the stronger chilling-induced PSI photoinhibition in the sun leaves was resulted from a greater electron flow from PSII to PSI. Furthermore, moderate PSII photoinhibition depressed electron flow to PSI and then protected PSI activity against further photodamage in chilled tobacco leaves. PMID:26941755

  17. Termination of Nutrient Import and Development of Vein Loading Capacity in Albino Tobacco Leaves

    PubMed Central

    Turgeon, Robert

    1984-01-01

    The sink-source conversion in developing leaves of tobacco (Nicotiana tabacum L.) was studied to determine whether import termination is caused by the onset of export or is related to achievement of positive carbon balance. Albino shoots were grown in vitro and grafted to detopped stems of green tobacco plants. Termination of import was studied by providing mature leaves of the stock plant with 14CO2 and detecting the presence of labeled nutrient in developing albino leaves by whole-leaf autoradiography. In albino leaves, import terminated progressively in the basipetal direction at the same stage of development as in leaves of green shoots. Starch was not present in the plastids of mesophyll cells of mature albino leaves but starch was synthesized when discs were cut from these leaves and incubated on 3 millimolar sucrose. Import ceased progressively in developing green leaves even when photosynthesis was prevented by darkening. It was concluded that cessation of import does not require achievement of positive carbon balance and is not the direct result of export initiation. To determine whether vein loading capacity develops in albino leaves, discs were cut from mature leaves and floated on [14C]sucrose solution. Uptake of label into the veins was detected by autoradiography and this uptake was sensitive to the phloem loading inhibitor p-chloromercuribenzenesulfonic acid. However, the amount of label taken up by veins in albino leaves was less than that taken up by veins of mature green leaves. Images Fig. 2 Fig. 4 Fig. 5 PMID:16663820

  18. Benefits and Harms of Sick Leave: Lack of Randomized, Controlled Trials

    ERIC Educational Resources Information Center

    Axelsson, Inge; Marnetoft, Sven-Uno

    2010-01-01

    The aim of this study was to try to identify those randomized controlled trials that compare sick leave with no sick leave or a different duration or degree of sick leave. A comprehensive, systematic, electronic search of Clinical Evidence, the Cochrane Library and PubMed, and a manual search of the Campbell Library and a journal supplement was…

  19. Monocot Leaves are Eaten Less than Dicot Leaves in Tropical Lowland Rain Forests: Correlations with Toughness and Leaf Presentation

    PubMed Central

    Grubb, Peter J.; Jackson, Robyn V.; Barberis, Ignacio M.; Bee, Jennie N.; Coomes, David A.; Dominy, Nathaniel J.; De La Fuente, Marie Ann S.; Lucas, Peter W.; Metcalfe, Daniel J.; Svenning, Jens-Christian; Turner, Ian M.; Vargas, Orlando

    2008-01-01

    Background and Aims In tropical lowland rain forest (TLRF) the leaves of most monocots differ from those of most dicots in two ways that may reduce attack by herbivores. Firstly, they are tougher. Secondly, the immature leaves are tightly folded or rolled until 50–100 % of their final length. It was hypothesized that (a) losses of leaf area to herbivorous invertebrates are generally greatest during leaf expansion and smaller for monocots than for dicots, and (b) where losses after expansion are appreciable any difference between monocots and dicots then is smaller than that found during expansion. Methods At six sites on four continents, estimates were made of lamina area loss from the four most recently mature leaves of focal monocots and of the nearest dicot shoot. Measurements of leaf mass per unit area, and the concentrations of water and nitrogen were made for many of the species. In Panama, the losses from monocots (palms) and dicots were also measured after placing fully expanded palm leaflets and whole dicot leaves on trails of leaf-cutter ants. Key Results At five of six sites monocots experienced significantly smaller leaf area loss than dicots. The results were not explicable in terms of leaf mass per unit area, or concentrations of water or nitrogen. At only one site was the increase in loss from first to fourth mature leaf significant (also large and the same in monocots and dicots), but the losses sustained during expansion were much smaller in the monocots. In the leaf-cutter ant experiment, losses were much smaller for palms than for dicots. Conclusions The relationship between toughness and herbivory is complex; despite the negative findings of some recent authors for dicots we hypothesize that either greater toughness or late folding can protect monocot leaves against herbivorous insects in tropical lowland rain forest, and that the relative importance varies widely with species. The difficulties of establishing unequivocally the roles of leaf

  20. Antioxidant and antityrosinase proanthocyanidins from Polyalthia longifolia leaves.

    PubMed

    Chen, Xiao-Xin; Liang, Ge; Chai, Wei-Ming; Feng, Hui-Ling; Zhou, Han-Tao; Shi, Yan; Chen, Qing-Xi

    2014-11-01

    In the present study the structure of proanthocyanidins from Polyalthia longifolia leaves was characterized with (13)C nuclear magnetic resonance, high performance liquid chromatography electrospray ionization mass spectrometry, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses. The results showed that the proanthocyanidins were mixture of homopolymers of B-type procyanidins with degree of polymerization up to 14-mer. Furthermore, the antioxidant activity of the proanthocyanidins was studied through 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) free-radical scavenging activities, and ferric reducing/antioxidant power assays. In addition, antityrosinase activity of the proanthocyanidins was investigated. The IC50 for 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) free-radical scavenging activity of the proanthocyanidins were 89.32 ± 12.07 and 76.79 ± 5.88 μg/mL, respectively; the ferric reducing/antioxidant power value was 710.54 ± 142.82 mg ascorbic acid equivalent/g dry weight. The IC50 for antityrosinase activity was 773.09 ± 1.47 μg/mL. In conclusion, the proanthocyanidins from P. longifolia leaves exhibited potent antioxidant and antityrosinase activities. This research would provide scientific evidence for the use of proanthocyanidins from P. longifolia leaves as antioxidant and antityrosinase agents.

  1. Associational resistance protects mangrove leaves from crab herbivory

    NASA Astrophysics Data System (ADS)

    Erickson, Amy A.; Bell, Susan S.; Dawes, Clinton J.

    2012-05-01

    While associational defenses have been well documented in many plant and algal ecosystems, this study is the first to document associational resistance in mangroves. Mangrove tree crab (Aratus pisonii) density and herbivory on three life-stages of the red mangrove (Rhizophora mangle) were documented in pure red versus mixed-species and predominantly non-red mangrove stands containing black (Avicennia germinans) and white (Laguncularia racemosa) mangroves in 1999-2000 in Tampa Bay, Florida. This study first established that R. mangle is the focal species in the context of associational resistance because it is damaged more than either of the other mangrove species. Next, it was hypothesized that crab density and leaf damage on R. mangle would be lower when in mixed-species and predominantly non-red versus red mangrove stands. A non-significant trend suggested that crab density varies among stands, and crab damage on R. mangle leaves was significantly lower in mixed-species and non-red stands. Mechanisms to explain associational resistance were examined. Positive Pearson correlations between the percent of adult R. mangle in a stand and both crab density and R. mangle leaf damage provided support for the resource concentration hypothesis. Limited support was found for the attractant-decoy hypothesis because the total amount of damaged leaves of all mangrove species combined typically differed among stands, suggesting that crabs were not shifting to alternative mangrove species to offset reduced availability of R. mangle leaves. Finally, while R. mangle seedlings were shorter in non-red stands compared to others, intra-specific differences in R. mangle leaf chemistry and sclerophylly among stands failed to explain associational patterns. These combined results argue for the need for additional experiments to elucidate mechanisms responsible for defensive plant associations in mangrove ecosystems and to determine whether such associations could be of use in mangrove

  2. Optical properties of intact leaves for estimating chlorophyll concentration.

    PubMed

    Carter, Gregory A; Spiering, Bruce A

    2002-01-01

    Changes in leaf chlorophyll content can serve as relative indicators of plant vigor and environmental quality. This study identified reflectance, transmittance, and absorptance wavebands and band ratios within the 400- to 850-nm range for intact leaves that could be used to estimate extracted leaf chlorophyll per unit leaf area (areal concentration) with minimal error. Leaf optical properties along with chlorophyll a, b, and a + b concentrations were measured for the planar-leaved sweetgum (Liquidambar styraciflua L.), red maple (Acer rubrum L.), wild grape (Vitis rotundifolia Michx.), and switchcane [Arundinaria gigantea (Walter) Muhl.], and for needles of longleaf pine (Pinus palustris Miller). Generally, reflectance, transmittance, and absorptance corresponded most precisely with chlorophyll concentrations at wavelengths near 700 nm, although regressions were also strong in the 550- to 625-nm range. A power function was superior to a simple linear function in yielding low standard deviations of the estimate (s). When data were combined among the planar-leaved species, s values were low at approximately 50 mumol/m2 out of a 940 mumol/m2 range in chlorophyll a + b at best-fit wavelengths of 707 to 709 nm. Minimal s values for chlorophyll a + b ranged from 32 to 62 mumol/m2 across species when band ratios having numerator wavelengths of 693 to 720 nm were used with the application of a power function. Optimal denominator wavelengths for the band ratios were 850 nm for reflectance and transmittance and 400 nm for absorptance. This information can be applied in designing field portable chlorophyll meters and in the landscape-scale remote sensing of plant responses to the environment.

  3. Optical properties of intact leaves for estimating chlorophyll concentration

    NASA Technical Reports Server (NTRS)

    Carter, Gregory A.; Spiering, Bruce A.

    2002-01-01

    Changes in leaf chlorophyll content can serve as relative indicators of plant vigor and environmental quality. This study identified reflectance, transmittance, and absorptance wavebands and band ratios within the 400- to 850-nm range for intact leaves that could be used to estimate extracted leaf chlorophyll per unit leaf area (areal concentration) with minimal error. Leaf optical properties along with chlorophyll a, b, and a + b concentrations were measured for the planar-leaved sweetgum (Liquidambar styraciflua L.), red maple (Acer rubrum L.), wild grape (Vitis rotundifolia Michx.), and switchcane [Arundinaria gigantea (Walter) Muhl.], and for needles of longleaf pine (Pinus palustris Miller). Generally, reflectance, transmittance, and absorptance corresponded most precisely with chlorophyll concentrations at wavelengths near 700 nm, although regressions were also strong in the 550- to 625-nm range. A power function was superior to a simple linear function in yielding low standard deviations of the estimate (s). When data were combined among the planar-leaved species, s values were low at approximately 50 mumol/m2 out of a 940 mumol/m2 range in chlorophyll a + b at best-fit wavelengths of 707 to 709 nm. Minimal s values for chlorophyll a + b ranged from 32 to 62 mumol/m2 across species when band ratios having numerator wavelengths of 693 to 720 nm were used with the application of a power function. Optimal denominator wavelengths for the band ratios were 850 nm for reflectance and transmittance and 400 nm for absorptance. This information can be applied in designing field portable chlorophyll meters and in the landscape-scale remote sensing of plant responses to the environment.

  4. Fungal epiphytes and endophytes of coffee leaves (Coffea arabica).

    PubMed

    Santamaría, Johanna; Bayman, Paul

    2005-07-01

    Plants harbor diverse communities of fungi and other microorganisms. Fungi are known to occur both on plant surfaces (epiphytes) and inside plant tissues (endophytes), but the two communities have rarely been compared. We compared epiphytic and endophytic fungal communities associated with leaves of coffee (Coffea arabica) in Puerto Rico. We asked whether the dominant fungi are the same in both communities, whether endophyte and epiphyte communities are equally diverse, and whether epiphytes and endophytes exhibit similar patterns of spatial heterogeneity among sites. Leaves of naturalized coffee plants were collected from six sites in Puerto Rico. Epiphytic and endophytic fungi were isolated by placing leaf pieces on potato dextrose agar without and with surface sterilization, respectively. A total of 821 colonies were isolated and grouped into 131 morphospecies. The taxonomic affinities of the four most common nonsporulating fungi were determined by sequencing the nuclear ribosomal internal transcribed spacer (ITS) region: two grouped with Xylaria and one each with Botryosphaeria and Guignardia. Of the most common genera, Pestalotia and Botryosphaeria were significantly more common as epiphytes; Colletotrichum, Xylaria, and Guignardia were significantly more common as endophytes. Suprisingly, more morphospecies occurred as endophytes than as epiphytes. Differences among sites in number of fungi per plant were significant. Thus epiphytic and endophytic communities differed greatly on a single leaf, despite living only millimeters apart, and both communities differed from site to site. Significant correlations between occurrence of fungal morphospecies suggested that fungi may have positive or negative effects on their neighbors. This is the first quantitative comparison of epiphytic and endophytic fungal floras in any plant, and the first to examine endophytic fungi or epiphytic fungi in leaves of coffee, one of the world's most valuable crops.

  5. Antigenotoxic activities of crude extracts from Acacia salicina leaves.

    PubMed

    Mansour, Hédi B; Boubaker, Jihed; Bouhlel, Inès; Mahmoud, Amor; Bernillon, Stéphane; Chibani, Jemni B; Ghedira, Kamel; Chekir-Ghedira, Leila

    2007-01-01

    For centuries, plants have been used in traditional medicines and there has been recent interest in the chemopreventive properties of compounds derived from plants. In the present study, we investigated the effects of extracts of Acacia salicina leaves on the genotoxicity of benzo[a]pyrene (B(a)P) and nifuroxazide in the SOS Chromotest. Aqueous, total oligomers flavonoids (TOF)-enriched, petroleum ether, chloroform, ethyl acetate, and methanol extracts were prepared from powdered Acacia leaves, and characterized qualitatively for the presence of tannins, flavonoids, and sterols. All the extracts significantly decreased the genotoxicity induced by 1 microg B(a)P (+S9) and 10 microg nifuroxazide (-S9). The TOF-enriched and methanol extracts decreased the SOS response induced by B(a)P to a greater extent, whereas the TOF-enriched and the ethyl acetate extracts exhibited increased activity against the SOS response produced by nifuroxazide. In addition, the aqueous, ethyl acetate, and methanol extracts showed increased activity in scavenging the 1,1-diphenyl- 2-picrylhydrazyl (DPPH) free radical, while 100-300 microg/ml of all the test extracts were active in inhibiting O2-production in a xanthine/xanthine oxidase system. In contrast, only the petroleum ether extract was effective at inhibiting nitroblue tetrazolium reduction by the superoxide radical in a nonenzymatic O2- -generating system. The present study indicates that extracts of A. salicina leaves are a significant source of compounds with antigenotoxic and antioxidant activity (most likely phenolic compounds and sterols), and thus may be useful for chemoprevention.

  6. Three new xanthones from the leaves of Garcinia lancilimba.

    PubMed

    Sun, Yating; Li, Dahong; Jia, Cuicui; Xue, Chunmei; Bai, Jiao; Li, Zhanlin; Hua, Huiming

    2016-04-01

    Three new prenylated xanthones, garcinexanthones G-I (1-3), together with fifteen known ones (4-18) were identified from the leaves of Garcinia lancilimba. Their structures were determined by extensive spectroscopic analyses. Most of the compounds exhibited inhibitory effects against HL-60 (human leukemia), A549 (human lung cancer), and MCF-7 (human breast cancer) cell lines. Among them, compounds 7, 17, and 13 exhibited the most pronounced growth inhibitory activity against HL-60, A549, and MCF-7 cell lines with GI50 values of 1.68, 4.88, and 6.28 μM, respectively.

  7. New glucose esters from the fresh leaves of Jacaranda mimosaefolia.

    PubMed

    Elusiyan, Christianah A; Olugbade, Tiwalade A

    2011-12-01

    From the fresh leaves of Jacaranda mimosaefolia were isolated Phytoquinoids 1-4 established as beta-D-glucopyranose 2-benzeneacetatel,6-bis(1-hydroxy-4-oxo-2,5-cyclohexadiene-1-acetate), for which the name Jacaranoside is proposed; beta-D-glucopyranose 2-(4-hydroxybenzeneacetate) 1,6-bis(1-hydroxy-4-oxo-2,5-cyclohexadiene-1-acetate), for which the name Jacarandol is proposed; beta-D-glucopyranose 2-benzeneacetate 1-(1-hydroxy-4-oxo-2,5-cyclohexadiene-1-acetate) and beta-D-glucopyranose 1,6-bis (1-hydroxy-4-oxo-2,5-cyclohexadiene-1-acetate) respectively.

  8. Bioactive sesquiterpene polyol esters from the leaves of Tripterygium wilfordii.

    PubMed

    Wang, Chao; Li, Chuang-Jun; Ma, Jie; Yang, Jing-Zhi; Chen, Xiao-Guang; Hou, Qi; Zhang, Dong-Ming

    2014-07-01

    Tripterygium wilfordii, a member of Celastraceae family, has been used as a traditional plant insecticide and a medicinal plant. Phytochemical investigation of the leaves of T. wilfordii has resulted in the isolation of eight sesquiterpene polyol esters triptersinines M-T (1-8) and one sesquiterpene pyridine alkaloid (9). The structures of the compounds were elucidated on the basis of spectroscopic data analyses, including UV, IR, MS, and NMR experiments. The inhibitory effects on nitric oxide production in LPS-induced macrophages of 1-9 were also evaluated.

  9. Analgesic and antipyretic effects of Capparis zeylanica leaves.

    PubMed

    Ghule, B V; Murugananthan, G; Yeole, P G

    2007-07-01

    The ethanol and water extracts of Capparis zeylanica leaves showed dose-dependent and significant (P<0.05) increases in pain threshold in tail-immersion test. Moreover, both the extracts (100-200 mg/kg) exhibited a dose-dependent inhibition of writhing and also showed a significant (P<0.001) inhibition of both phases of the formalin pain test. The water extract (200 mg/kg) significantly (P<0.01) reversed yeast-induced fever. Preliminary phytochemical screening of the extracts showed the presence of alkaloids, flavonoids, saponins glycosides, terpenoids, tannins, proteins and carbohydrates.

  10. 41-D crew leaves operations and checkout building at KSC

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The members of the 41-D crew leave operations and checkout building at Kennedy Space Center (KSC) to make their way to Launch Pad 39A. Leading the group is Henry W. Hartsfield Jr., commander; Michael L. Coats, pilot is left center. The mission specialists are Steven A. Hawley, second right, Richard M. (Mike) Mullane, right center, and Judith A. Resnik. Charles D. Walker, payload specialist, follows Resnik. Behind the blue-suited crewmembers are George W.S. Abbey, left, director of Flight Crew Operations and John W. Young, chief of the Astronaut Office.

  11. Polyphenolic compounds isolated from the leaves of Myrtus communis.

    PubMed

    Yoshimura, Morio; Amakura, Yoshiaki; Tokuhara, Mie; Yoshida, Takashi

    2008-07-01

    Four hydrolyzable tannins [oenothein B (1), eugeniflorin D(2) (2), and tellimagrandins I (3) and II (4)], two related polyphenolic compounds [gallic acid (5) and quinic acid 3,5-di-O-gallate (6)], and four myricetin glycosides [myricetins 3-O-beta-D-xyloside (7), 3-O-beta-D-galactoside (8), 3-O-beta-D-galactoside 6''-O-gallate (9), and 3-O-alpha-L-rhamnoside (10)] were isolated from the leaves of Myrtus communis. Antioxidant activities of the isolated compounds were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay.

  12. Cytotoxic phloroglucinols from the leaves of Myrtus communis.

    PubMed

    Cottiglia, Filippo; Casu, Laura; Leonti, Marco; Caboni, Pierluigi; Floris, Costantino; Busonera, Bernardetta; Farci, Pamela; Ouhtit, Aicha; Sanna, Giuseppina

    2012-02-24

    Bioactivity-guided fractionation of a dichloromethane extract of the leaves of Myrtus communis led to the isolation of phloroglucinol derivatives. The structures of the new myrtucommulones J, K, and L (1-3) and the previously known myrtucommulone A (4) were elucidated on the basis of extensive 1D and 2D NMR experiments as well as high-resolutionmass spectrometry. Myrtucommulone J was obtained as a tautomeric pair (1/1a). The compounds were tested in vitro for their cytotoxic and antibacterial activities.

  13. Characterization of Inositol-containing Phosphosphingolipids from Tobacco Leaves

    PubMed Central

    Kaul, Karan; Lester, Robert L.

    1975-01-01

    A method for a large scale extraction of phosphoglycosphingolipids from the leaves of Nicotiana tabacum L. has been developed. The phosphosphingolipid concentrate consists of a dozen or more polar lipids as judged by thin layer chromatography. Two of these lipids were purified by chromatography on porous silica beads and partially characterized. These lipids are formulated as: N-acetylglucosamidoglucuronidoinositol phosphorylceramide and glucosamidoglucuronidoinositol phosphorylceramide. Although not fully characterized, the other lipids in the concentrate are inositol-containing phosphosphingolipids with a higher carbohydrate content. PMID:16659016

  14. Chemical composition and analgesic activity of Calophyllum brasiliense leaves.

    PubMed

    da Silva, K L; dos Santos, A R; Mattos, P E; Yunes, R A; Delle-Monache, F; Cechinel-Filho, V

    2001-01-01

    This paper describes a phytochemical and pharmacological study with Calophyllum brasiliense leaves, a medicinal plant employed in folk medicine for the treatment of several ailments. Based on spectroscopic evidence, five phenolic compounds were identified as hyperin (hyperoside), amentoflavone, quercetin, gallic acid, and protocatechuic acid. The fractions and some phenolic compounds exhibited significant analgesic activity against the writhing test and in relation to the second phase (inflammatory pain) of the formalin test in mice, suggesting that this plant can be useful for the treatment of dolorous processes.

  15. What makes staff consider leaving the health service in Malawi?

    PubMed Central

    2014-01-01

    Background Malawi faces a severe shortage of health workers, a factor that has contributed greatly to high maternal mortality in the country. Most clinical care is performed by mid-level providers (MLPs). While utilization of these cadres in providing health care is a solution to the current shortages, demotivating factors within the Malawian health system are pushing them into private, non-governmental, and other non-health related positions. This study aims to highlight these demotivating factors by exploring the critical aspects that influence MLPs’ intention to leave their jobs. Methods This descriptive qualitative study formed part of the larger Health Systems Strengthening for Equity (HSSE) study. Data presented in this paper were collected in Malawi using the Critical Incident Analysis tool. Participants were asked to narrate an incident that had happened during the past three months which had made them seriously consider leaving their job. Data were subjected to thematic analysis using NVivo 8 software. Results Of the 84 respondents who participated in a Critical Incident Analysis interview, 58 respondents (69%) indicated they had experienced a demotivating incident in the previous three months that had made them seriously consider leaving their job. The most commonly cited critical factors were being treated unfairly or with disrespect, lack of recognition of their efforts, delays and inconsistencies in salary payments, lack of transparent processes and criteria for upgrading or promotion, and death of patients. Conclusion Staff motivation and an enabling environment are crucial factors for retaining MLPs in the Malawian health system. This study revealed key ‘tipping points’ that drive staff to seriously consider leaving their jobs. Many of the factors underlying these critical incidents can be addressed by improved management practices and the introduction of fair and transparent policies. Managers need to be trained and equipped with effective

  16. 11. CONTINUATION OF LATERAL LEAVING THE DIVERSION STRUCTURE WEST OF ...

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

    11. CONTINUATION OF LATERAL LEAVING THE DIVERSION STRUCTURE WEST OF LOWER DERBY LAKE (SECTION 2), SHOWING MEASURING GAUGE. - Highline Canal, Sand Creek Lateral, Beginning at intersection of Peoria Street & Highline Canal in Arapahoe County (City of Aurora), Sand Creek lateral Extends 15 miles Northerly through Araphoe County, City & County of Denver, & Adams County to its end point, approximately 1/4 mile Southest of intersectioin of D Street & Ninth Avenue in Adams County (Rocky Mountain Arsenal, Commerce City Vicinity), Commerce City, Adams County, CO

  17. A new benzophenone glycoside from the leaves of Mitracarpus villosus.

    PubMed

    Ngwoke, Kenneth G; Orame, Njideka; Liu, Shuai; Okoye, Festus B C; Daletos, Georgios; Proksch, Peter

    2017-03-22

    A new benzophenone glycoside, mitraphenone A (1), together with three known compounds (2-4) were isolated from the leaves of the traditionally used medicinal plant Mitracarpus villosus (Rubiaceae) collected in Nigeria. A combination of one- and two-dimensional NMR spectroscopic and mass spectrometric measurements were carried out to identify the structure of 1. All isolated compounds (1-4) were screened for their antibacterial activity against several Gram-positive and Gram-negative bacteria. Compound 1 exhibited moderate activity against Enterococcus faecium (strains ATCC 35667 and ATCC 700221) and Staphylococcus aureus ATCC 25923 with MIC values ranging from 25 to 50 μM.

  18. Flavonoids and triterpenes from the leaves of Artocarpus fulvicortex.

    PubMed

    Jamil, Shajarahtunnur; Taherb, Muhammad; Sirat, Hasnah M; Othman, Nur Azlin

    2012-12-01

    Five flavonoids, 5-hydroxy-(6:7,3':4')-di(2,2-dimethylpyrano)flavone 1, carpachromene 2, cycloartocarpesin 3, norartocarpetin 4 and 2'-hydroxy-4,4',6'-trimethoxychalcone 5, along with three triterpenes, friedelin 6, lupeol 7 and 13-sitosterol 8 were isolated for the first time from the leaves of Artocarpus fulvicortex F.M. Jarrett. The structures of these compounds were established by analysis of their spectroscopic (1D and 2D NMR) and spectrometric (MS) data, as well as by comparison of these with those reported in the literature.

  19. Studies of laser induced-breakdown spectroscopy of holly leaves

    NASA Astrophysics Data System (ADS)

    Zhang, D. C.; Ma, X.; Wen, W. Q.; Liu, H. P.; Zhang, P. J.

    2009-09-01

    The LIBS spectra of holly leaves produced by Nd:YAG nanosecond laser has been investigated. More than 20 elements and molecules were identified from the spectra. The influence of laser wavelength upon analysis of plant samples via LIBS technique has been investigated. The comparison of LIBS spectra shows that the spectrum for 1064 nm irradiation is more intense than the one for 266 nm irradiation by the same pulse energy in the near-UV region. Investigation of the influence of laser wavelength for LIBS can help to improve the analytical capabilities of LIBS.

  20. Cytotoxic alkaloids from stems, leaves and twigs of Dasymaschalon blumei.

    PubMed

    Chanakul, Waraporn; Tuchinda, Patoomratana; Anantachoke, Natthinee; Pohmakotr, Manat; Piyachaturawat, Pawinee; Jariyawat, Surawat; Suksen, Kanoknetr; Jaipetch, Tharworn; Nuntasaen, Narong; Reutrakul, Vichai

    2011-10-01

    Bioassay-guided fractionation of the cytotoxic ethyl acetate extract from the stems of Dasymaschalon blumei (Annonaceae) led to the isolation of four aristololactam alkaloids, including the hitherto unknown 3,5-dihydroxy-2,4-dimethoxyaristolactam (1), as well as the three known compounds, aristolactam BI, goniopedaline, and griffithinam. Additionally, the cytotoxic extract from the combined leaves and twigs of the same plant yielded three known oxoaporphine alkaloids, oxodiscoguattine, dicentrinone, and duguevalline. The structures of aristolactams and oxoaporphine alkaloids were elucidated on the basis of spectroscopic methods. All isolates were evaluated for cytotoxicity against a panel of mammalian cancer cell lines and a noncancerous human embryonic kidney cell Hek 293.

  1. Three novel compounds from the leaves of Smallanthus sonchifolius.

    PubMed

    Qiu, Ying-Kun; Kang, Ting-Guo; Dou, De-Qiang; Liang, Li; Dong, Feng

    2008-01-01

    Three novel compounds, together with five known ingredients, octacosanol, 3',4',5-trihydroxy-3,7-dimethoxyflavone, 3,4-dihydroxybenzaldehyde, isorhamnetin, and ent-kaurane-3beta,16beta,17-triol, were obtained from the leaves of Smallanthus sonchifolius (yacon), and their structures were elucidated as ent-kaurane-3beta,16beta,17,18-tertol (1), 3R,7E-9-butoxyl-megastigma-3-ol-3-O-beta-D-glucopyranoside (2), and 3S,5R,6Z-megastigma-6-en-3,5,8,9-tertol (3) on the basis of spectroscopic and chemical methods.

  2. Cucurbitacins from the Leaves of Citrullus colocynthis (L.) Schrad.

    PubMed

    Chawech, Rachid; Jarraya, Raoudha; Girardi, Cynthia; Vansteelandt, Marieke; Marti, Guillaume; Nasri, Imen; Racaud-Sultan, Claire; Fabre, Nicolas

    2015-09-30

    Two new tetracyclic cucurbitane-type triterpene glycosides were isolated from an ethyl acetate extract of Citrullus colocynthis leaves together with four known cucurbitacins. Their structures were established on the basis of their spectroscopic data (mainly NMR and mass spectrometry). Evaluation of the in vitro cytotoxic activity of the isolated compounds against two human colon cancer cell lines (HT29 and Caco-2) and one normal rat intestine epithelial cell line (IEC6), revealed that one of the isolated compounds presented interesting specific cytotoxic activity towards colorectal cell lines.

  3. New flavonol glycosides from the leaves of Caragana brachyantha.

    PubMed

    Perveen, Shagufta; Al-Taweel, Areej Mohammad; Al-Musayeib, Nawal; Fawzy, Ghada Ahmed; Khan, Afsar; Mehmood, Rashad; Malik, Abdul

    2015-01-01

    Two new flavonol glycosides, brachysides C and D, together with three known flavonol glycosides, were isolated from the leaves of Caragana brachyantha. The structures of brachysides C and D were elucidated on the basis of detailed spectroscopic analysis as quercetin 5-O-[α-L-rhamnopyranosyl-(1 → 6)-β-D-glucopyranoside]-7-O-[α-L-rhamnopyranoside] and quercetin 5-O-[α-L-rhamnopyranosyl-(1 → 6)-β-D-glucopyranoside]-7-O-[α-L-rhamnopyranoside]-4'-O-[α-L-rhamnopyranoside], respectively. The presence of flavonol tetra- and triglycosides bearing a sugar moiety at position 5 was the first report from this genus Caragana.

  4. Indole alkaloids from the leaves of Philippine Alstonia scholaris.

    PubMed

    Macabeo, Allan Patrick G; Krohn, Karsten; Gehle, Dietmar; Read, Roger W; Brophy, Joseph J; Cordell, Geoffrey A; Franzblau, Scott G; Aguinaldo, Alicia M

    2005-05-01

    The first seco-uleine alkaloids, manilamine (1) (18-hydroxy-19,20-dehydro-7,21-seco-uleine) and N4-methyl angustilobine B (2), were isolated from the (pH 5) alkaloid extract of Philippine Alstonia scholaris leaves together with the known indole alkaloids 19,20-(E)-vallesamine (3), angustilobine B N4-oxide (4), 20(S)-tubotaiwine (5), and 6,7-seco-angustilobine B (6). The structure of the alkaloids was established from MS and NMR experiments.

  5. Spasmolytic constituents from Eucalyptus camaldulensis var. obtusa leaves.

    PubMed

    Begum, S; Farhat, F; Sultana, I; Siddiqui, B S; Shaheen, F; Gilani, A H

    2000-09-01

    Phytochemical studies on the leaves of Eucalyptus camaldulensis var. obtusa have resulted in the isolation of a new triterpenoid camaldulin (3beta-formyloxyurs-11-en-28,13beta-olide) (1) along with ursolic acid lactone acetate (2), ursolic acid lactone (3), betulinic acid (4), and beta-sitosterol 3-O-beta-D-glucopyranoside (5). The structures were assigned on the basis of 1D and 2D NMR studies. Compounds 1-3 were tested for spasmolytic activity and were found to possess calcium antagonist activity.

  6. Steroidal glycosides from the leaves of Cestrum nocturnum.

    PubMed

    Mimaki, Yoshihiro; Watanabe, Kazuki; Sakagami, Hiroshi; Sashida, Yutaka

    2002-12-01

    Further phytochemical analysis aimed at the steroidal glycoside constituents of the leaves of Cestrum nocturnum has resulted in the isolation of eight new steroidal glycosides (1-8), which were classified into a spirostanol saponin (1), a furostanol saponin (2), a pseudo-furostanol saponin (3), two pregnane glycosides (4, 5), two cholestane glycosides (6, 7), and pregnane-carboxylic acid gamma-lactone glycoside (8), and of two known spirostanol glycosides (9, 10). The structures of the new compounds were elucidated on the basis of chemical and spectroscopic evidence.

  7. Phenylpropanoid Glycosides from the Leaves of Ananas comosus.

    PubMed

    Chen, Wen-Hao; Huang, Xiao-Juan; Shu, Huo-Ming; Hui, Yang; Guo, Fei-Yan; Song, Xiao-Ping; Ji, Ming-Hui; Chen, Guang-Ying

    2015-12-01

    Two new phenylpropanoid glycosides, named β-D-(1-O-acetyl-3,6-O-diferuloyl) fructofuranosyl β-D-6'-O-acetylglucopyranoside (1) and β-D-(1-O-acetyl-3,6-O-diferuloyl) fructofuranosyl α-D-glucopyranoside (2), along with two known analogues (3-4) and four glycerides (5-8), were isolated from the EtOAc extract of the leaves of Ananas comosus. Their structures were elucidated on the basis of 1D- and 2D-NMR analyses, as well as HR-ESI-MS experiments. Compounds 1-4 showed significant antibacterial activities against Staphylococcus aureus and Escherichia coli.

  8. Leave taking and overtime behavior as related to demographic, health, and job variables

    NASA Technical Reports Server (NTRS)

    Arnoldi, L. B.; Townsend, J. C.

    1969-01-01

    An intra-installation model is formulated that correlates demographic, health and job related variables to the various types and amounts of leave and overtime taking behavior of employees. Statistical comparison of composite health ratings assigned to subjects based upon clinical criteria and bio-statistical data show that those employees who take the most annual leave as well as sick leave are the ones that have the poorest health ratings; employees who put in the most overtime have also the poorest health records. Stress effects of peak activity periods increase use of sick leave immediately after peak activity but not the use of annual leave.

  9. Effect of Gibberellic Acid on Crown Gall Tumor Induction in Aging Primary Pinto Bean Leaves 1

    PubMed Central

    Anand, Vinod K.; Bauer, Chris; Heberlein, Gary T.

    1975-01-01

    Gibberellic acid was tested for its effect on tumor induction by Agrobacterium tumefaciens in primary pinto bean (Phaseolus vulgaris) leaves in various stages of development. The hormone was found to promote tumor induction in partially aged leaves but did not effect tumor induction in very young leaves or in fully matured leaves. It is suggested that the natural loss of susceptibility to tumor induction in maturing pinto bean leaves is associated with a concomitant loss of endogenous gibberellins and/or a sensitivity to gibberellins. PMID:16659201

  10. 18O enrichment in phosphorus pools extracted from soybean leaves.

    PubMed

    Pfahler, Verena; Dürr-Auster, Thilo; Tamburini, Federica; Bernasconi, M Stefano; Frossard, Emmanuel

    2013-01-01

    The objective of this study was to investigate the isotopic composition of oxygen bound to phosphate (δ(18)O-PO(4)) in different phosphorus (P) pools in plant leaves. As a model plant we used soybean (Glycine max cv Toliman) grown in the presence of ample P in hydroponic cultures. The leaf blades were extracted with 0.3 M trichloroacetic acid (TCA) and with 10 M nitric acid. These extractions allowed measurement of the TCA-soluble reactive P (TCA P) that is rapidly cycled within the cell and the total leaf P. The difference between total leaf P and TCA P yielded the structural P which includes organic P compounds not extractable by TCA. P uptake and its translocation and transformation within the soybean plants lead to an (18)O enrichment of TCA P (δ(18)O-PO(4) between 16.9 and 27.5‰) and structural P (δ(18)O-PO(4) between 42.6 and 68.0 ‰) compared with 12.4‰ in the phosphate in the nutrient solution. δ(18)O values of phosphate extracted from soybean leaves grown under optimal conditions are greater than the δ(18)O-PO(4) values of the provided P source. Furthermore, the δ(18)O-PO(4) of TCA P seems to be controlled by the δ(18)O of leaf water and the activity of inorganic pyrophosphatase or other pyrophosphatases.

  11. Coronatine Facilitates Pseudomonas syringae Infection of Arabidopsis Leaves at Night

    PubMed Central

    Panchal, Shweta; Roy, Debanjana; Chitrakar, Reejana; Price, Lenore; Breitbach, Zachary S.; Armstrong, Daniel W.; Melotto, Maeli

    2016-01-01

    In many land plants, the stomatal pore opens during the day and closes during the night. Thus, periods of darkness could be effective in decreasing pathogen penetration into leaves through stomata, the primary sites for infection by many pathogens. Pseudomonas syringae pv. tomato (Pst) DC3000 produces coronatine (COR) and opens stomata, raising an intriguing question as to whether this is a virulence strategy to facilitate bacterial infection at night. In fact, we found that (a) biological concentration of COR is effective in opening dark-closed stomata of Arabidopsis thaliana leaves, (b) the COR defective mutant Pst DC3118 is less effective in infecting Arabidopsis in the dark than under light and this difference in infection is reduced with the wild type bacterium Pst DC3000, and (c) cma, a COR biosynthesis gene, is induced only when the bacterium is in contact with the leaf surface independent of the light conditions. These findings suggest that Pst DC3000 activates virulence factors at the pre-invasive phase of its life cycle to infect plants even when environmental conditions (such as darkness) favor stomatal immunity. This functional attribute of COR may provide epidemiological advantages for COR-producing bacteria on the leaf surface. PMID:27446113

  12. Photosynthetic activity of vascular bundles in Plantago media leaves.

    PubMed

    Miszalski, Zbigniew; Skoczowski, Andrzej; Silina, Ekaterina; Dymova, Olga; Golovko, Tamara; Kornas, Andrzej; Strzalka, Kazimierz

    2016-10-01

    Photosynthetic processes in the leaf lamina and midribs of Plantago media were investigated using plants grown in high light (HL) or low light (LL) conditions. The fluorescence parameters, which indicate photochemical/photosynthetic activity, were different in HL and LL grown plants, but no major differences between lamina and midribs were found. An OJIP test (chlorophyll a fluorescence transient induction) of LL grown plants, indicative of the chloroplast electron transport chain, also showed both tissues to be similar. In HL plants, a partial blockage of electron flow between QA (the primary plastoquinone electron acceptor of PSII) and QB (the secondary plastoquinone acceptor of PSII) was found, and this was less visible in midribs. The effective dissipation of quantum energy per reaction center (DI0/RC) was similar in both tissues of HL grown plants, while in the midribs of LL leaves, this process seemed to be less effective. Measurements of (13)C discrimination showed that the midrib tissues of LL and HL leaves effectively used β-carboxylation products to accumulate their biomass. Thus, the well protected activity of electron transport in midribs with their limited capacity to fix CO2 from the air may indicate the involvement of this tissue in β-carboxylation, transport or signaling. Carbon accumulated in roots showed a lower (13)C discrimination value (more negative) than the values observed in lamina. This could indicate that roots are supplied with assimilates mostly during the light phase of the day cycle with intensive C3 photosynthesis.

  13. Anion and divalent cation activation of phosphoglycolate phosphatase from leaves.

    PubMed

    Husic, H D; Tolbert, N E

    1984-02-15

    Phosphoglycolate (P-glycolate) phosphatase was purified 223-fold from spinach leaves by (NH4)2SO4 fractionation, DEAE-cellulose chromatography, and Sephadex G-200 chromatography. The partially purified enzyme had a broad pH optimum between 5.6 and 8.0 and was specific for the hydrolysis of P-glycolate with a Km (P-glycolate) of 26 microM. The enzyme was activated by divalent cations including Mg2+, Co2+, Mn2+, and Zn2+, and by anions including Cl-, Br-, NO-3, and HCOO-. Neither anions nor divalent cations activated the enzyme without the other. The P-glycolate phosphatase activities from tobacco leaves or the green algae, Chlamydomonas reinhardtii, also required Mg2+ and were activated by chloride. In addition, the enzyme was allosterically inhibited by ribose 5-phosphate. The activation of P-glycolate phosphatase by both anions and divalent cations and the inhibition by ribose 5-phosphate may be involved in the in vivo regulation of P-glycolate phosphatase activity.

  14. Measurement of CA1P and CA in leaves

    SciTech Connect

    Moore, B.d.; Kobza, J.; Seemann, J.R. )

    1990-05-01

    Carboxyarabinitol-1-phosphate (CA1P) and carboxyarabinitol (CA) were assayed in leaves by isotope dilution. {sup 14}C-labeled standards were synthesized from (2-{sup 14}C) CABP using acid (CA1P) or alkaline (CA) phosphatase. Either was added to boiling 80% EtOH along with liquid N{sub 2}-killed leaves. Each was largely purified by anion exchange chromatography. CA1P samples were subjected to 2D-TLE/TLC. The specific activity of the {sup 14}C-containing spot was measured using alkaline phosphatase. CA samples were run on an HPLC and the specific activity was determined using a UV monitor and a flow-through radioisotope detector. In 3 of the tested species, light/dark amount of CA1P (nmol/mg Chl) were kidney bean, 0.7/67; sugar beet, 0.8/33; and Alocasia, 0/3.4. Light/dark CA levels (nmol/mg Chl) in these respective species were 897/653, 3.2/3.5, and 5.7/4.6. These results support the hypothesis that CA is a product of CA1P metabolism in vivo under high light, but also indicate that CA is not the only intermediate involved in CA1P synthesis under low light/dark conditions.

  15. Regulation of sucrose synthesis in water stressed leaves

    SciTech Connect

    Daie, J.; Aloni, B. )

    1991-05-01

    Alteration in carbon metabolism and carbohydrate partitioning occur in drought stressed plants. Some species accumulate large quantities of starch in the chloroplast, which may be used to support sucrose synthesis under conditions of limited carbon supply. The authors monitored chemical partitioning of carbon between sugars and starch and the activity of sucrose phosphate synthase (SPS) and fructose 1,6 bisphosphatase (FBPase) in the source leaves of water stressed tomatoes. Plants were stressed by withdrawing water for 10 days and rewatered for recovery. Water potential dropped from {minus}0.8 to {minus}2.2MPA in 10 days, but recovered to control level 2 days after rewatering. Photosynthetic rates as measured by the activity of Rubisco followed similar patterns to those of water potential. After 10 days, leaf starch levels decreased to less than 50% of control. Sucrose levels did not increase significantly, but hexose levels increased 3-4 fold during the stress period, and decreased to control levels 1 day after rewatering. FBPase activity decreased and SPS activity increased under stress conditions. Upon rewatering, the activity of FBPase and SPS returned to control levels. Presence of large quantities of hexose and activation of SPS in stressed leaves suggested that additional sucrose synthesized under stress was hydrolyzed to hexoses, presumably due to enhanced invertase activity.

  16. Wound healing activity of Argyreia nervosa leaves extract

    PubMed Central

    Singhal, AK; Gupta, H; Bhati, VS

    2011-01-01

    Background: Argyreia nervosa (Convolvulaceae) plant is an example of hallucinogenic plant. The antiseptic, anti-inflammatory, antispasmodic, antibacterial, antiviral, antifungal, anticonvulsant, nootropic, antifertility and aphrodisiac properties have already been reported for this plant. Aim: The aim of present work was to evaluate the wound healing property in normal and diabetic animals by oral and topical administration of ethanolic extract of leaves. Materials and Methods: Phytochemical investigations showed the presence of various biochemicals (alkaloids, flavonoids, carbohydrates, triterpenoids, proteins, saponins, steroids, tannins). A single injection of alloxan monohydrate (120 mg/kg, i.p.) prepared in citrate buffer (0.1 M, pH 4.5) was administered to produce diabetes in rats and mice, after overnight fasting. Excision wounds (sized 300 mm2 and of 2 mm depth) were used for the study of rate of contraction of wound and epithelization. The means of wound area measurement between groups at different time intervalswere compared using one-way analysis of variance (ANOVA), followed by Dunnet's test. Results: Extracts of A. nervosa showed significant wound healing effect in normal (topically treated) and diabetic (both topically and orally treated) rats. In diabetic rats, the topically treated group showed more significant effect than the orally treated groups. Conclusion: The present study demonstrates that A. nervosa leaves extract applied topically promotes healing of wounds more significantly as compared to oral application, in both normal rats and alloxan induced diabetic rats, where healing is otherwise delayed. PMID:23776770

  17. Taxanes from Shells and Leaves of Corylus avellana.

    PubMed

    Ottaggio, Laura; Bestoso, Federica; Armirotti, Andrea; Balbi, Alessandro; Damonte, Gianluca; Mazzei, Mauro; Sancandi, Monica; Miele, Mariangela

    2008-01-01

    Paclitaxel is an effective antineoplastic agent originally extracted in low yield from the bark of Taxus brevifolia. Although it was generally considered a particular metabolite of Taxus sp., paclitaxel was recently found in hazel cell cultures. The aim of the present work was to verify whether hazel differentiated tissues could be used as a commercial source of paclitaxel and other taxanes. Thus, shells and leaves of hazel plants were analyzed by ELISA and HPLC-MS. Both shell and leaf extracts contained taxanes. Among these, paclitaxel, 10-deacetylbaccatin III, baccatin III, paclitaxel C, and 7-epipaclitaxel were identified and quantified. Hazel extracts also showed biological activity, inhibiting metaphase to anaphase transition in a human tumor cell line. The level of total taxanes in leaves was higher than in shells collected in the same period from the same plants. However, the finding of these compounds in shells, which are considered discarded material and are mass produced by many food industries, is of interest for the future availability of paclitaxel and other antineoplastic compounds.

  18. Missed opportunity: patients who leave emergency departments without being seen.

    PubMed

    Baibergenova, Akerke; Leeb, Kira; Jokovic, Aleksandra; Gushue, Sharon

    2006-05-01

    The rate of patients who visit emergency departments (EDs) but leave before being evaluated and treated is an important indicator of ED performance. This study examines patient- and hospital-level characteristics that may increase the risk of patients leaving EDs before being seen. The data are from the National Ambulatory Care Reporting System, an administrative database, and represent 4.3 million patient visits made to 163 Ontario EDs between April 2003 and March 2004. Among these data, the proportion that left without being seen (LWBS) was 3.1% (136,805). The rate of LWBS was highest among patients aged 15 to 35 years, those with less acute conditions and facilities that handle the highest volume of patients. Facility rates were positively correlated with facility median ED length of stay, annual facility volume and percentage of inpatient admissions. Understanding patient and facility characteristics that increase rates of LWBS may inform the process of developing measures to ensure timely access to ED care for all who seek it.

  19. Antioxidant compounds from the leaves of Peucedanum japonicum thunb.

    PubMed

    Hisamoto, Masashi; Kikuzaki, Hiroe; Ohigashi, Hajime; Nakatani, Nobuji

    2003-08-27

    Seventeen compounds were isolated from the n-butanol soluble fraction of the leaves of Peucedanum japonicum Thunb. On the basis of MS and various NMR spectroscopic techniques, the structures of the isolated compounds were determined as isoquercitrin (1), rutin (2), 3-O-caffeoylquinic acid (3), 4-O-caffeoylquinic acid (4), 5-O-caffeoylquinic acid (5), cnidioside A (6), praeroside II (7), praeroside III (8), apterin (9), esculin (10), (R)-peucedanol (11), (R)-peucedanol 7-O-beta-d-glucopyranoside (12), l-tryptophan (13), uracil (14), guanosine (15), uridine (16), and thymidine (17). All compounds except 11 and 12 were isolated for the first time from P. japonicum. Several isolated compounds were quantified by high-performance liquid chromatography analysis. In addition, all isolated compounds were examined for radical scavenging on 1,1-diphenyl-2-picrylhydrazyl radical and for inhibition of oxidation of liposome induced by 2,2'-azobis(2-amidinopropane)dihydrochloride. Compounds 2-5 were found to be the major potent constituents, which contribute to the antioxidant activity of P. japonicum leaves.

  20. Photosynthetic strategies in leaves and stems of Egeria densa.

    PubMed

    Rascio, N; Mariani, P; Tommasini, E; Bodner, M; Larcher, W

    1991-10-01

    Photosynthetic mechanisms have been compared in leaves and, separately, in stems of Egeria densa Planch. In order to correlate the structural and functional characteristics of the two organs (1) the ultrastructural features of leaves and stems have been studied and (2) their photosynthetic activity has been evaluated by measuring in vivo both oxygen evolution and the kinetics of chlorophyll fluorescence. The results confirm the aquatic behaviour of the leaf which is able to utilize inorganic C supplied both as CO2 and HCO 3 (-) . In this respect, the different wall organization found in the two cell layers of the leaf is particularly interesting, since it could be related to the known polar mechanism of inorganic-C uptake. The stem, by contrast, behaves rather as an aerial organ, needing very high CO2 concentrations in the aquatic environment in order to carry out photosynthesis. In the stem, the aerenchyma plays a role in supplying the green cells with gaseous respiratory CO2, thus facilitating the photosynthetic activity of the submerged stems.