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Sample records for maire ratassepp ervi

  1. Larval competition between Aphidius ervi and Praon volucre (Hymenoptera: Braconidae: Aphidiinae) in Macrosiphum euphorbiae (Hemiptera: Aphididae).

    PubMed

    Sidney, Lívia Alvarenga; Bueno, Vanda Helena Paes; Lins, Juracy Caldeira; Sampaio, Marcus Vinicius; Silva, Diego Bastos

    2010-10-01

    Interspecific competition between parasitoid larvae may influence the size, structure, and stability of the population, leading to a reduction in total parasitism and thus restricting the pest control. Aphidius ervi (Haliday) and Praon volucre (Haliday) are endoparasitoids that possess a wide host range and present considerable potential for the biological control of the aphid Macrosiphum euphorbiae (Thomas). The larval competition between A. ervi and P. volucre, and the possible intrinsic competitive superiority of one of the parasitoids in M. euphorbiae, have been studied. In single parasitism experiments, mated parasitoid females (n=10) were maintained individually in contact with M. euphorbiae hosts (n=30) inside petri dishes containing lettuce leaf discs and maintained in environmental chamber at 22 ± 1°C, 70 ± 10% RH, and 12-h photophase. The multiple parasitism experiments consisted of exposing single parasitized aphids (n=120) to the second parasitoid species. Two oviposition events were performed with a 4-h interval between them, namely the following: sequence A (oviposition by A. ervi, followed by P. volucre) and sequence B (oviposition by P. volucre, followed by A. ervi). Oviposition sequence A generated 24 A. ervi and 55 P. volucre adults, whereas oviposition sequence B generated 23 and 49 adults. P. volucre is an intrinsically superior competitor compared with A. ervi, and the use of the two species simultaneously may result in competitive exclusion and influence the stability of the parasitoid population.

  2. [Quality of different aphids species as hosts for the parasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae: Aphidiinae)].

    PubMed

    Sidney, Lívia A; Bueno, Vanda H P; Lins, Juracy C; Silva, Diego B; Sampaio, Marcus V

    2010-01-01

    The suitability of Macrosiphum euphorbiae (Thomas), Aulacorthum solani (Kaltenbach) and Acyrthosiphon kondoi Shinji (Hemiptera: Aphididae) as hosts for the aphid parasitoid Aphidius ervi Haliday was evaluated by assessing host size, host preference, and host quality. Tests were carried out in an environmental chamber at 22±1ºC, 70±10% RH and 12h photophase. Replicates (11) consisted of one 24h-old mated female of A. ervi without a previous oviposition experience. Female was released into a Petri dish (5 cm) with 20 2nd and 3rd instars of one of each aphid species tested on a leaf disc of the host plant onto a 1% water-agar layer. Parasitoid emergency was lower in A. kondoi (78.7%) compared to M. euphorbiae (92.2%) and A. solani (91.7%). Acyrthosiphon kondoi (0.36 mm) was the smallest host. The parasitoid showed preference (74.0% parasitism) for M. euphorbiae, the largest host (hind tibia length=0.73 mm), which in turn yielded larger A. ervi females (0.75 mm).

  3. Heme-binding activity of methoxyflavones from Pentzia monodiana Maire (Asteraceae).

    PubMed

    Ortiz, Sergio; Dali-Yahia, Kamel; Vasquez-Ocmin, Pedro; Grougnet, Raphaël; Grellier, Philippe; Michel, Sylvie; Maciuk, Alexandre; Boutefnouchet, Sabrina

    2017-04-01

    A heme-binding assay based on mass spectrometry was performed on P. monodiana Maire (Asteraceae) extracts to identify metabolites able to form adducts with heminic part of haemoglobin, as potential antimalarial drugs. Main adducts were characterized and their stability was measured. Isolation of main constituents of P. monodiana Maire lead to identification of the two methoxyflavones 3'-O-methyleupatorin (7) and artemetin (8) involved in the adducts formation. Four seco-tanapartholides (1-4), a guaianolide (5), a germacranolide (6) and two other methoxyflavones (9, 10) were also characterized. Evaluation of isolated compounds on P. falciparum and T. brucei brucei showed a moderate antiprotozoal activity of the two methoxyflavones.

  4. Placenta-Like Structure of the Aphid Endoparasitic Wasp Aphidius ervi: A Strategy of Optimal Resources Acquisition

    PubMed Central

    Sabri, Ahmed; Hance, Thierry; Leroy, Pascal D.; Frère, Isabelle; Haubruge, Eric; Destain, Jacqueline; Compère, Philippe; Thonart, Philippe

    2011-01-01

    Aphidius ervi (Hymenoptera: Braconidae) is an entomophagous parasitoid known to be an effective parasitoid of several aphid species of economic importance. A reduction of its production cost during mass rearing for inundative release is needed to improve its use in biological control of pests. In these contexts, a careful analysis of its entire development phases within its host is needed. This paper shows that this parasitoid has some characteristics in its embryological development rather complex and different from most other reported insects, which can be phylogenetically very close. First, its yolkless egg allows a high fecundity of the female but force them to hatch from the egg shell rapidly to the host hemocoel. An early cellularisation allowing a rapid differentiation of a serosa membrane seems to confirm this hypothesis. The serosa wraps the developing embryo until the first instar larva stage and invades the host tissues by microvilli projections and form a placenta like structure able to divert host resources and allowing nutrition and respiration of embryo. Such interspecific invasion, at the cellular level, recalls mammal's trophoblasts that anchors maternal uterine wall and underlines the high adaptation of A. ervi to develop in the host body. PMID:21526196

  5. Potential effects of plant protease inhibitors, oryzacystatin I and soybean Bowman-Birk inhibitor, on the aphid parasitoid Aphidius ervi Haliday (Hymenoptera, Braconidae).

    PubMed

    Azzouz, H; Campan, E D M; Cherqui, A; Saguez, J; Couty, A; Jouanin, L; Giordanengo, P; Kaiser, L

    2005-08-01

    Protease inhibitors (PIs) have been shown to cause lethal and sublethal effects on aphids depending on the kind of PI and aphid species. Therefore, these proteins might affect aphid parasitoids directly by inhibiting their digestive proteolysis or indirectly via their development in a less suitable host. In our study, the risk of exposure and the potential effects of soybean Bowman-Birk inhibitor (SbBBI) and oryzacystatin I (OCI) on the aphid endoparasitoid Aphidius ervi were investigated using artificial diet to deliver PIs. Immunoassays showed that both SbBBI and OCI were detected in the honeydew of aphids reared on artificial diet containing these recombinant proteins at 100 microg/mL. However, only SbBBI was detected in parasitoid larvae, while this PI could not be detected in adult parasitoids emerged from PI-intoxicated aphids. Enzymatic inhibition assays showed that digestive proteolytic activity of larvae and adults of A. ervi predominantly relies on serine proteases and especially on chymotrypsin-like activity. Bioassays using SbBBI and OCI on artificial diet were performed. A. ervi that developed on intoxicated aphids had impaired fitness. Thus development and parasitism success of parasitoids exposed to OCI were severely affected. On the contrary, SbBBI only altered significantly female size and sex ratio. Direct exposure to PIs through adult food intake did not affect female's longevity, while SbBBI and OCI (100 microg/mL) induced 69% and 30% inhibition of digestive protease activity, respectively. These studies made it possible to estimate the risk of exposure to plant PIs and the sensitivity of the aphid parasitoid A. ervi to these entomotoxins, by combining immunological, biochemical and biological approaches. First it pointed out that only immature stages are affected by PIs. Secondly, it documented two different modes of effect, according to the nature of the PIs and both host and parasitoid susceptibility. OCI prevented the development of A. ervi

  6. The effect of larval and early adult experience on behavioural plasticity of the aphid parasitoid Aphidius ervi (Hymenoptera, Braconidae, Aphidiinae)

    NASA Astrophysics Data System (ADS)

    Villagra, Cristian A.; Pennacchio, Francesco; Niemeyer, Hermann M.

    2007-11-01

    The relevance of the integration of preimaginal and eclosion experiences on the subsequent habitat preferences and mate finding by the adult has been rarely tested in holometabolous insects. In this work, the effect of larval and early adult experiences on the behavioural responses of adult males of the aphid parasitoid, Aphidius ervi, towards volatiles from the host-plant complex (HPC) and from conspecific females were evaluated. Two experience factors were considered: host diet (normal diet=ND; artificial diet=AD), and eclosion, i.e. extraction or non-extraction of the parasitoid larva from the parasitised aphid (extracted=EX; non-extracted=NE). Thus, four treatments were set up: ND/NE, ND/EX, AD/NE and AD/EX. Glass Y-tube olfactometers were used to investigate the responses of adult A. ervi males to the odour sources used. Males from the ND/NE treatment showed a shorter latency to the first choice of olfactometer arms, displayed a marked preference towards the HPC olfactometer arm, and spent more time in the HPC arm than males from the other treatments. Only the interaction of host diet and eclosion experiences proved to be relevant in explaining the differences in latency to first choice, time spent in olfactometers arms, and behaviours displayed in the olfactometer arms. These results show the importance of the integration of larval and eclosion experiences in the development of stereotyped responses of the adults. This process may involve memory retention from the preimaginal and emergence period, but further research is needed to disentangle the contribution of each stage. The response to conspecific females was much less affected by the treatments in relation to first arm choice and times in olfactometer arms, suggesting a pheromone-mediated behaviour, even though a prompter and more intense wing fanning courtship behaviour was registered in the ND/NE males compared to males from the AD/NE treatment. These results show that sexual behaviours are less

  7. Optimal Experimental Condition of IR pMAIRS Calibrated by Using an Optically Isotropic Thin Film Exhibiting the Berreman Effect.

    PubMed

    Shioya, Nobutaka; Norimoto, Shingo; Izumi, Naoki; Hada, Miyako; Shimoaka, Takafumi; Hasegawa, Takeshi

    2016-07-08

    Infrared (IR) p-polarized multiple-angle incidence resolution spectrometry (pMAIRS) is a useful spectroscopic tool for revealing the molecular anisotropic structure in a thin film, which is used for the molecular orientation analysis of many functionalized organic thin films. Infrared pMAIRS provides both in-plane (IP) and out-of-plane (OP) vibrational mode spectra, which are influenced by the choice of the angles of incidence, i.e., angle set. To obtain quantitatively reliable pMAIRS spectra, therefore, the optimal angle set must be revealed. In a former study, an optimization study was carried out on a silicon substrate by using the band intensity ratio of the IP and OP spectra of highly oriented molecules in a thin film, which has a problem that the optimized results cannot be used for another substrate. In the present study, a totally new idea using an optically isotropic thin film as a standard sample is proposed to comprehensively explore the optimal angle set on various substrates: the band shift due to the Berreman effect of a strongly absorbing compound is used, instead of the band intensity. This new approach makes the pMAIRS calibration for various substrates a much easier task. With the optimal angle set, the molecular orientation angle in the film calculated by the pMAIRS spectra is also found to be reliable quantitatively. This technique opens a user-friendly way to a reliable molecular orientation analysis in an ultrathin film using IR pMAIRS.

  8. NASA Satellite and Model Data and Services to Support NEESPI and MAIRS

    NASA Astrophysics Data System (ADS)

    Shen, S.; Leptoukh, G. G.; Gerasimov, I.

    2009-12-01

    During the past two to three decades, the Northern Eurasia and Asian Monsoon regions have experienced significant changes in agriculture, industry and economics. Studies have indicated that land use and land cover changes due to climate change and human activities not only changes local climate but also influence global climate system. However, the interaction between human activity, land processes, and climate change are not fully understood. Having integrated interdisciplinary multi-sensor data are important for speeding up studies of climate and environmental changes. During the past three years, more than thirty monthly and daily global satellite datasets for atmospheric, land surface, and cryosphere were collected and an automated data processing, archive, and distribution system was established in supporting the Northern Eurasia Earth Science Partnership Initiative (NEESPI) project. Data tools and services, such as temporal and spatial search, parameter and spatial subsetting, advanced data downloading, are available. Most data have been integrated into the Web-based online data analyses and visualizations system, Giovanni (Goddard Interactive Online Visualization ANd aNalysis Infrastructure). The established data services infrastructure will be used and improved further for supporting Monsoon Asia Integrated Regional Study (MARIS) project. We plan to integrate higher resolution land process data into the Giovanni system, such as vegetation index, land surface temperature, and active fire at 5km and 1km from the standard MODIS products. About 30 years (since 1979) simulated land products from the NASA Global Land Data Assimilation System (GLDAS), and simulated atmospheric products from the NASA MERRA project will be available through the NASA MAIRS data portal. Due to large overlap of the geographic coverage and many similar interesting of NEESPI and MAIRS, collected data will serve for both projects. In this presentation, in addition to the introduction of

  9. Pre-pupation behaviour of the aphid parasitoid Aphidius ervi (Haliday) and its consequences for pre-imaginal learning

    NASA Astrophysics Data System (ADS)

    Gutiérrez-Ibáñez, Cristián; Villagra, Cristian A.; Niemeyer, Hermann M.

    2007-07-01

    Olfactory learning may occur at different stages of insect ontogeny. In parasitoid wasps, it has been mostly shown at adult emergence, whilst it remains controversial at pre-imaginal stages. We followed larval growth of the parasitoid wasp, Aphidius ervi Haliday, inside the host aphid, Acyrthosiphom pisum Harris, and characterised in detail the behaviour of third instar larvae. We found that just before cocoon spinning begins, the third instar larva bites a hole through the ventral side of the mummified aphid exoskeleton. We then evaluated whether this period of exposure to the external environment represented a sensitive stage for olfactory learning. In our first experiment, the third instar larvae were allowed to spin their cocoon on the host plant ( Vicia faba L.) surface or on a plastic plate covering the portion of the host plant exposed to the ventral opening. Recently emerged adults of the first group showed a preference for plant volatiles in a glass Y-olfactometer, whereas no preference was found in adults of the second group. In a second experiment, during the period in which the aphid carcass remains open or is being sealed by cocoon spinning, third instar larvae were exposed for 24 h to either vanilla odours or water vapours as control. In this experiment, half of the parasitoid larvae were later excised from the mummy to avoid further exposure to vanilla. Adult parasitoids exposed to vanilla during the larval ventral opening of the mummy showed a significant preference for vanilla odours in the olfactometer, regardless of excision from the mummy. The larval behaviour described and the results of the manipulations performed are discussed as evidences for the acquisition of olfactory memory during the larval stage and its persistence through metamorphosis.

  10. Parasitic Wasps Aphidius ervi are More Attracted to a Blend of Host-Induced Plant Volatiles than to the Independent Compounds.

    PubMed

    Takemoto, Hiroyuki; Takabayashi, Junji

    2015-09-01

    Arthropodal natural enemies respond to volatiles from plants infested by their prey/host herbivores (herbivore-induced plant volatiles; HIPVs). However, the relative importance of HIPV blends vs. each compound in the blend in attracting natural enemies is not fully understood. In this study, we investigated the response of a parasitic wasp, Aphidius ervi, to HIPVs that were specific or nonspecific to infestations by its host aphid, Acyrthosiphon pisum. To select such compounds, we compared the volatiles emitted from broad bean plants infested by either A. pisum (host) or by Aphis craccivora (nonhost), and selected the host-specific HIPVs β-myrcene, n-octanal, and α-phellandrene, and host-nonspecific HIPVs (E)-β-ocimene, γ-terpinene, and linalool as test compounds. For each compound, we used a range that covered the amounts emitted from infested broad bean plants for bioassays. Female wasps preferred n-octanal and (E)-β-ocimene at 10-ng and 30-ng doses over clean air. Interestingly, the wasps preferred α-phellandrene at 0.1-ng and 30-ng doses, but not at 1-ng and 10-ng doses. The wasps repelled linalool over clean air at 1-ng and 0.1-ng doses. We then mixed the equivalent amounts of the six compounds to test the effect of the blend. The wasps responded to a blend of six HIPV components at all concentrations tested (0.001 ng each to 5 ng each). These results suggested that the blend provided more useful information for female wasps than the individual compounds. The possible use of the single component and the blend for the biological control of A. ervi is discussed.

  11. New bioactive dihydrofuranocoumarins from the roots of the Tunisian Ferula lutea (Poir.) Maire.

    PubMed

    Ben Salem, Saoussen; Jabrane, Aymen; Harzallah-Skhiri, Fethia; Ben Jannet, Hichem

    2013-07-15

    A phytochemical investigation of the roots of Ferula lutea (Poir.) Maire led to the isolation of new dihydrofuranocoumarins as two inseparable isomers, (-)-5-hydroxyprantschimgin 1 and (-)-5-hydroxydeltoin 2, together with eight known compounds, (-)-prantschimgin 3, (-)-deltoin 4, psoralen 5, xanthotoxin 6, umbelliferone 7, caffeic acid 8, β-sitosterol 9 and stigmasterol 10. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D and 2D NMR experiments and mass spectroscopy analysis, as well as by comparison with literature data. The anti-acetylcholinesterase and cytotoxic effects of the isolates and antioxidant activities of the mixture (1+2) were also evaluated in this work. Results showed that the mixture (1+2) has the most cytotoxic activity with IC50 values 0.29±0.05 and 1.61±0.57μM against the cell lines HT-29 and HCT 116, respectively. The greatest acetylcholinesterase inhibitory activity (IC50=0.76±0.03) was exhibited by the xanthotoxin 6. In addition, the mixture (1+2) was investigated for its antioxidant activity and showed IC50 values 18.56, 13.06, 7.59, and 4.81μM towards DPPH free radical scavenging, ABTS radical monocation, singlet oxygen and hydrogen peroxide, respectively.

  12. [Analgesic activity of different nonvolatile extracts of Nepeta atlantica Ball and Nepeta Tuberosa L. ssp. reticulata (Desf.) Maire].

    PubMed

    Bouidida, El Houcine; Alaoui, Katim; Cherrah, Yahia; Chammache, Malika; Il Idrissi, Abdelkader

    2008-01-01

    Different extracts of Nepeta atlantica Ball and Nepeta tuberosa L. ssp. reticulata (Desf.) Maire contain mainly secondary metabolites with iridoïd lactonic and glucosidic type, also with triterpine lupan type.The aerial part of each species is crushed, then extracted in methanol by cold maceration, called global extracts. The global extracts will be extracted through various solvents: initially by hexane, then by dichloromethane, after that by ethyl acetate and at the end by buthanol. Each one of the obtained extracts will be used for the following trials: i) Tail flick trial on the rat for central morphine-like analgesic activity; ii) Koster trial on the mouse for peripheral analgesic activity. The evaluation of the central and peripheral analgesic activities for the pre-cited extracts was realized after optimal doses determination of the global extracts activities for both species.The peripheral analgesic activity test on the mouse showed that, for 60 mg/kg intra peritoneum (IP), the hexanic, dichloromethanic, ethyl acetate and butanic extracts have a protection power against abdominal cramp respectively around 89.78%, 81.73%, 70.9% et 69.05% for Nepeta atlantica Ball, and around 89.16%, 82.98%, 71.52% et 70.27% for Nepeta tuberosa L. ssp. reticulata.Central morphine-like analgesic activity on the rat showed that, for both spices under 60 mg/kg IP, the central analgesic activity effect is significantly for two extracts only: dichloromethane and ethyl acetate.

  13. Protective Activity of Total Polyphenols from Genista quadriflora Munby and Teucrium polium geyrii Maire in Acetaminophen-Induced Hepatotoxicity in Rats.

    PubMed

    Baali, Nacera; Belloum, Zahia; Baali, Samiya; Chabi, Beatrice; Pessemesse, Laurence; Fouret, Gilles; Ameddah, Souad; Benayache, Fadila; Benayache, Samir; Feillet-Coudray, Christine; Cabello, Gérard; Wrutniak-Cabello, Chantal

    2016-04-01

    Oxidative stress is a major cause of drug-induced hepatic diseases and several studies have demonstrated that diet supplementation with plants rich in antioxidant compounds provides a variety of health benefits in these circumstances. Genista quadriflora Munby (Gq) and Teucrium polium geyrii Maire (Tp) are known to possess antioxidant and numerous biological properties and these endemic plants are often used for dietary or medicinal applications. Herein, we evaluated the beneficial effect of rich-polyphenol fractions of Gq and Tp to prevent Acetaminophen-induced liver injury and investigated the mechanisms involved in this protective action. Rats were orally administered polyphenolic extracts from Gq or Tp (300 mg/kg) or N-acetylcysteine (NAC: 200 mg/kg) once daily for ten days prior to the single oral administration of Acetaminophen (APAP: 1 g/kg). The results show that preventive administration of polyphenolic extracts from Gq or Tp exerts a hepatoprotective influence during APAP treatment by improving transaminases leakage and liver histology and stimulating antioxidant defenses. Besides, suppression of liver CYP2E1, GSTpi and TNF-α mRNA levels, with enhancement of mitochondrial bioenergetics may contribute to the observed hepatoprotection induced by Gq and Tp extracts. The effect of Tp extract is significantly higher (1.5-2 fold) than that of Gq extract and NAC regarding the enhancement of mitochondrial functionality. Overall, this study brings the first evidence that pretreatment with these natural extracts display in vivo protective activity against APAP hepatotoxicity through improving mitochondrial bioenergetics, oxidant status, phase I and II enzymes expression and inflammatory processes probably by virtue of their high total polyphenols content.

  14. [Acute toxicity and analgesic activity of the global extracts of Nepeta atlantica Ball and Nepeta tuberosa L. ssp. reticulata (Desf.) Maire].

    PubMed

    Bouidida, El Houcine; Alaoui, Katim; Cherrah, Yahia; Fkih-Tetouani, Souad; Idrissi, Abdelkader Il

    2006-01-01

    The global extracts of Nepeta atlantica Ball and Nepeta tuberosa L. ssp. reticulata (Desf.) Maire are especially rich in secondary metabolites of the type iridoid lactonique and glucosidique and of type lupane triterpine. The aerial part of each species is crushed, and then extracted by cold maceration in methanol. These total extracts are in the form of suspension in Arabic gum with 5%, they are tested on the mice for the tests of acute toxicity like for the peripheral analgesic activity according to the test of Koster; and also on the rats for the central analgesic activity of the morphine type based on the test "Tail Flick". The acute toxicity evaluation of these extracts follows upon the determination of the lethal amounts 50% of essential oils from these two species, already given it is specified here by the lethal dose 50% (DL50) of 1672 +/- 232 mg/kg with confidence limits [1030 - 2320] mg/kg for Nepeta atlantica and 1401 +/- 97.29 mg/kg with confidence limits [1130 - 1670] mg/kg for Nepeta tuberosa L. ssp. reticulata. The tests of Koster in the mouse and the "Tail Flik" in the rat showed that the global extracts of the studied species have all two greatly peripheral analgesic activity with an important protection against abdominal cramp 67.91% and 75.53% for 60 mg/kg IP respectively for Nepeta atlantica and Nepeta tuberosa L. ssp. Reticulata, which rise up to 90.10% and 92.89% for 120 mg/kg IP. A central morphine like analgesic activity is record with 120 mg/kg IP for the two species.

  15. Protective Activity of Total Polyphenols from Genista quadriflora Munby and Teucrium polium geyrii Maire in Acetaminophen-Induced Hepatotoxicity in Rats

    PubMed Central

    Baali, Nacera; Belloum, Zahia; Baali, Samiya; Chabi, Beatrice; Pessemesse, Laurence; Fouret, Gilles; Ameddah, Souad; Benayache, Fadila; Benayache, Samir; Feillet-Coudray, Christine; Cabello, Gérard; Wrutniak-Cabello, Chantal

    2016-01-01

    Oxidative stress is a major cause of drug-induced hepatic diseases and several studies have demonstrated that diet supplementation with plants rich in antioxidant compounds provides a variety of health benefits in these circumstances. Genista quadriflora Munby (Gq) and Teucrium polium geyrii Maire (Tp) are known to possess antioxidant and numerous biological properties and these endemic plants are often used for dietary or medicinal applications. Herein, we evaluated the beneficial effect of rich-polyphenol fractions of Gq and Tp to prevent Acetaminophen-induced liver injury and investigated the mechanisms involved in this protective action. Rats were orally administered polyphenolic extracts from Gq or Tp (300 mg/kg) or N-acetylcysteine (NAC: 200 mg/kg) once daily for ten days prior to the single oral administration of Acetaminophen (APAP: 1 g/kg). The results show that preventive administration of polyphenolic extracts from Gq or Tp exerts a hepatoprotective influence during APAP treatment by improving transaminases leakage and liver histology and stimulating antioxidant defenses. Besides, suppression of liver CYP2E1, GSTpi and TNF-α mRNA levels, with enhancement of mitochondrial bioenergetics may contribute to the observed hepatoprotection induced by Gq and Tp extracts. The effect of Tp extract is significantly higher (1.5–2 fold) than that of Gq extract and NAC regarding the enhancement of mitochondrial functionality. Overall, this study brings the first evidence that pretreatment with these natural extracts display in vivo protective activity against APAP hepatotoxicity through improving mitochondrial bioenergetics, oxidant status, phase I and II enzymes expression and inflammatory processes probably by virtue of their high total polyphenols content. PMID:27043622

  16. Thermal and pressure stability of myrosinase enzymes from black mustard (Brassica nigra L. W.D.J. Koch. var. nigra), brown mustard (Brassica juncea L. Czern. var. juncea) and yellow mustard (Sinapsis alba L. subsp. maire) seeds.

    PubMed

    Okunade, Olukayode Adediran; Ghawi, Sameer Khalil; Methven, Lisa; Niranjan, Keshavan

    2015-11-15

    This study investigates the effects of temperature and pressure on inactivation of myrosinase extracted from black, brown and yellow mustard seeds. Brown mustard had higher myrosinase activity (2.75 un/mL) than black (1.50 un/mL) and yellow mustard (0.63 un/mL). The extent of enzyme inactivation increased with pressure (600-800 MPa) and temperature (30-70° C) for all the mustard seeds. However, at combinations of lower pressures (200-400 MPa) and high temperatures (60-80 °C), there was less inactivation. For example, application of 300 MPa and 70 °C for 10 min retained 20%, 80% and 65% activity in yellow, black and brown mustard, respectively, whereas the corresponding activity retentions when applying only heat (70° C, 10 min) were 0%, 59% and 35%. Thus, application of moderate pressures (200-400 MPa) can potentially be used to retain myrosinase activity needed for subsequent glucosinolate hydrolysis.

  17. Linear Logistic Test Modeling with R

    ERIC Educational Resources Information Center

    Baghaei, Purya; Kubinger, Klaus D.

    2015-01-01

    The present paper gives a general introduction to the linear logistic test model (Fischer, 1973), an extension of the Rasch model with linear constraints on item parameters, along with eRm (an R package to estimate different types of Rasch models; Mair, Hatzinger, & Mair, 2014) functions to estimate the model and interpret its parameters. The…

  18. Analytical understanding of multiple-angle incidence resolution spectrometry based on a classical electromagnetic theory.

    PubMed

    Itoh, Yuki; Kasuya, Akiyoshi; Hasegawa, Takeshi

    2009-07-09

    Infrared multiple-angle incidence resolution spectrometry (IR-MAIRS) is a unique spectroscopic technique to retrieve both surface-parallel (in-plane; IP) and -perpendicular (out-of-plane; OP) molecular vibration spectra simultaneously from an identical thin-film deposited on a high refractive index substrate, and the measurement theory was constructed by the use of a theoretical framework of regression equation. The core part of the MAIRS theory is found in the weighting factor matrix, R, used for a linear combination, which was constructed in an unusual manner. Because a regression equation does not strictly correlate the left- and right-hand sides of the equation, R matrix cannot directly be deduced from Maxwell's equation. Although the conventional studies using IR-MAIRS gave excellent empirical results, a strict physical understanding of MAIRS is necessary; otherwise, we cannot rely on it at least quantitatively. In the present study, the MAIRS theory has first been analyzed by the use of Maxwell's equations inductively. As a result, both MAIRS-IP and -OP spectra have readily been expressed as a linear combination of the Im(epsilon(x)) and Im(-1/epsilon(z)) functions that correspond to the conventional transmission and reflection-absorption spectra. Through the analysis of coefficients of the linear combination, MAIRS has proved to be reliably useful for analysis of thin film on a high refractive index substrate.

  19. Parasitic wasp responses to symbiont-based defense in aphids

    PubMed Central

    2012-01-01

    Background Recent findings indicate that several insect lineages receive protection against particular natural enemies through infection with heritable symbionts, but little is yet known about whether enemies are able to discriminate and respond to symbiont-based defense. The pea aphid, Acyrthosiphon pisum, receives protection against the parasitic wasp, Aphidius ervi, when infected with the bacterial symbiont Hamiltonella defensa and its associated bacteriophage APSE (Acyrthosiphon pisum secondary endosymbiont). Internally developing parasitoid wasps, such as A. ervi, use maternal and embryonic factors to create an environment suitable for developing wasps. If more than one parasitoid egg is deposited into a single aphid host (superparasitism), then additional complements of these factors may contribute to the successful development of the single parasitoid that emerges. Results We performed experiments to determine if superparasitism is a tactic allowing wasps to overcome symbiont-mediated defense. We found that the deposition of two eggs into symbiont-protected aphids significantly increased rates of successful parasitism relative to singly parasitized aphids. We then conducted behavioral assays to determine whether A. ervi selectively superparasitizes H. defensa-infected aphids. In choice tests, we found that A. ervi tends to deposit a single egg in uninfected aphids, but two or more eggs in H. defensa-infected aphids, indicating that oviposition choices may be largely determined by infection status. Finally, we identified differences in the quantity of the trans-β-farnesene, the major component of aphid alarm pheromone, between H. defensa-infected and uninfected aphids, which may form the basis for discrimination. Conclusions Here we show that the parasitic wasp A. ervi discriminates among symbiont-infected and uninfected aphids, and changes its oviposition behavior in a way that increases the likelihood of overcoming symbiont-based defense. More generally

  20. Specialization of bacterial endosymbionts that protect aphids from parasitoids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infection by the bacterial endosymbiont HAMILTONELLA DEFENSA is capable of protecting the pea aphid from parasitism by APHIDIUS ERVI and the black bean aphid from parasitism by LYSIPHLEBUS FABARUM. Here we investigate protection of a third aphid species, the cowpea aphid, APHIS CRACCIVORA, from 4 p...

  1. Diagnosis of diabetes diseases using an Artificial Immune Recognition System2 (AIRS2) with fuzzy K-nearest neighbor.

    PubMed

    Chikh, Mohamed Amine; Saidi, Meryem; Settouti, Nesma

    2012-10-01

    The use of expert systems and artificial intelligence techniques in disease diagnosis has been increasing gradually. Artificial Immune Recognition System (AIRS) is one of the methods used in medical classification problems. AIRS2 is a more efficient version of the AIRS algorithm. In this paper, we used a modified AIRS2 called MAIRS2 where we replace the K- nearest neighbors algorithm with the fuzzy K-nearest neighbors to improve the diagnostic accuracy of diabetes diseases. The diabetes disease dataset used in our work is retrieved from UCI machine learning repository. The performances of the AIRS2 and MAIRS2 are evaluated regarding classification accuracy, sensitivity and specificity values. The highest classification accuracy obtained when applying the AIRS2 and MAIRS2 using 10-fold cross-validation was, respectively 82.69% and 89.10%.

  2. Utilizing Higher Resolution Land Surface Remote Sensing Data for Assessing Recent Trends over Asia Monsoon Region

    NASA Technical Reports Server (NTRS)

    Shen, Suhung; Leptoukh, Gregory

    2010-01-01

    The slide presentation discusses the integration of 1-kilometer spatial resolution land temperature data from the Moderate Resolution Imaging Spectroradiometer (MODIS), with 8-day temporal resolution, into the NASA Monsoon-Asia Integrated Regional Study (MAIRS) Data Center. The data will be available for analysis and visualization in the Giovanni data system. It discusses the NASA MAIRS Data Center, presents an introduction to the data access tools, and an introduction of Products available from the service, discusses the higher resolution Land Surface Temperature (LST) and presents preliminary results of LST Trends over China.

  3. Expectations About Civilian Labor Markets and Army Officer Retention

    DTIC Science & Technology

    2011-01-01

    Design and Structure: New Lessons from Behavioral Finance , Oxford: Oxford University Press, 2004, pp. 137–153. Feldman, Daniel C., “The Nature...from Behavioral Finance , Oxford: Oxford University Press, 2004, pp. 157–184. Mackin, Patrick C., Paul F. Hogan, and Lee S. Mairs, A Multiperiod Model

  4. Generalized Disjunctive Well-Founded Semantics for Logic Programs

    DTIC Science & Technology

    1990-03-01

    0 e, -o’se ’Mair t?’* te- ’r 0’e’"A #w ’ ntre. .. rnn ir 141* vo~rc, 1 pnec "’ 1"a -I ! 9!e ata leea.. 1"d :Cn’a.0ting Jrnc I*..... q -..e IIcCti on

  5. Beyond Mastery: Postmodern College Composition.

    ERIC Educational Resources Information Center

    Juncker, Clara

    1990-01-01

    Describes a modestly postmodern experiment (in an Advanced Composition course) with feminine linguistic spaces (Woolf, Welty, and Mairs) crisscrossing academic borders and existing simultaneously within and without traditional institutional modes. Uses Luce Irigaray's essay "Is the Subject of Science Sexed?" to comment on this undertaking. (SR)

  6. Toward a Rhetorical Theory of Metaphor: A Transactive Analysis of Metaphor in the Arts.

    ERIC Educational Resources Information Center

    Bannister, Linda; And Others

    Three professors at Loyola Marymount University, Los Angeles, reflected about a course they taught together on the use of metaphor in language, art and literature. In examining a wide range of art works with their students, including prose by E. A. Poe, Nancy Mairs, Henry James, and Woody Allen and movies such as "Dr.…

  7. Understanding China. Footnotes. Volume 12, Number 1

    ERIC Educational Resources Information Center

    Kuehner, Trudy

    2007-01-01

    On October 21-22, 2006, FPRI's Marvin Wachman Fund for International Education hosted 46 teachers from 26 states across the country for a weekend of discussion on teaching about China. Sessions included: (1) Classical Chinese Thought and Culture and Early Chinese History (Victor Mair); (2) State and Society in Late Imperial China (Matthew Sommer);…

  8. The `Alice in Wonderland' Experience—Ergot Alkaloid Therapy for Prolactin-Secreting Pituitary Tumors

    PubMed Central

    Williams, Ralph C.; Sherman, Charles; Buckman, Maire T.

    1983-01-01

    This discussion was selected from the weekly Grand Rounds in the Department of Medicine, University of New Mexico School of Medicine and Veterans Administration Medical Center, Albuquerque. Taken from a transcription, it has been edited by Drs Charles Sherman, Resident in Medicine, and Maire T. Buckman, Associate Professor of Medicine and Chief, Endocrinology Section, Veterans Administration Medical Center, Alburquerque. Images PMID:6858128

  9. Influence of temperature on patch residence time in parasitoids: physiological and behavioural mechanisms.

    PubMed

    Moiroux, Joffrey; Abram, Paul K; Louâpre, Philippe; Barrette, Maryse; Brodeur, Jacques; Boivin, Guy

    2016-04-01

    Patch time allocation has received much attention in the context of optimal foraging theory, including the effect of environmental variables. We investigated the direct role of temperature on patch time allocation by parasitoids through physiological and behavioural mechanisms and its indirect role via changes in sex allocation and behavioural defences of the hosts. We compared the influence of foraging temperature on patch residence time between an egg parasitoid, Trichogramma euproctidis, and an aphid parasitoid, Aphidius ervi. The latter attacks hosts that are able to actively defend themselves, and may thus indirectly influence patch time allocation of the parasitoid. Patch residence time decreased with an increase in temperature in both species. The increased activity levels with warming, as evidenced by the increase in walking speed, partially explained these variations, but other mechanisms were involved. In T. euproctidis, the ability to externally discriminate parasitised hosts decreased at low temperature, resulting in a longer patch residence time. Changes in sex allocation with temperature did not explain changes in patch time allocation in this species. For A. ervi, we observed that aphids frequently escaped at intermediate temperature and defended themselves aggressively at high temperature, but displayed few defence mechanisms at low temperature. These defensive behaviours resulted in a decreased patch residence time for the parasitoid and partly explained the fact that A. ervi remained for a shorter time at the intermediate and high temperatures than at the lowest temperature. Our results suggest that global warming may affect host-parasitoid interactions through complex mechanisms including both direct and indirect effects on parasitoid patch time allocation.

  10. Survival to parasitoids in an insect hosting defensive symbionts: a multivariate approach to polymorphic traits affecting host use by its natural enemy.

    PubMed

    Bilodeau, Emilie; Guay, Jean-Frédéric; Turgeon, Julie; Cloutier, Conrad

    2013-01-01

    Insect parasitoids and their insect hosts represent a wide range of parasitic trophic relations that can be used to understand the evolution of biotic diversity on earth. Testing theories of coevolution between hosts and parasites is based on factors directly involved in host susceptibility and parasitoid virulence. We used controlled encounters with potential hosts of the Aphidius ervi wasp to elucidate behavioral and other phenotypic traits of host Acyrthosiphon pisum that most contribute to success or failure of parasitism. The host aphid is at an advanced stage of specialization on different crop plants, and exhibits intra-population polymorphism for traits of parasitoid avoidance and resistance based on clonal variation of color morph and anti-parasitoid bacterial symbionts. Randomly selected aphid clones from alfalfa and clover were matched in 5 minute encounters with wasps of two parasitoid lineages deriving from hosts of each plant biotype in a replicated transplant experimental design. In addition to crop plant affiliation (alfalfa, clover), aphid clones were characterized for color morph (green, pink), Hamiltonella defensa and Regiella insecticola symbionts, and frequently used behaviors in encounters with A. ervi wasps. A total of 12 explanatory variables were examined using redundancy analysis (RDA) to predict host survival or failure to A. ervi parasitism. Aphid color was the best univariate predictor, but was poorly predictive in the RDA model. In contrast, aphid host plant and symbionts were not significant univariate predictors, but significant predictors in the multivariate model. Aphid susceptibility to wasp acceptance as reflected in host attacks and oviposition clearly differed from its suitability to parasitism and progeny development. Parasitoid progeny were three times more likely to survive on clover than alfalfa host aphids, which was compensated by behaviorally adjusting eggs invested per host. Strong variation of the predictive power of

  11. Influence of temperature on patch residence time in parasitoids: physiological and behavioural mechanisms

    NASA Astrophysics Data System (ADS)

    Moiroux, Joffrey; Abram, Paul K.; Louâpre, Philippe; Barrette, Maryse; Brodeur, Jacques; Boivin, Guy

    2016-04-01

    Patch time allocation has received much attention in the context of optimal foraging theory, including the effect of environmental variables. We investigated the direct role of temperature on patch time allocation by parasitoids through physiological and behavioural mechanisms and its indirect role via changes in sex allocation and behavioural defences of the hosts. We compared the influence of foraging temperature on patch residence time between an egg parasitoid, Trichogramma euproctidis, and an aphid parasitoid, Aphidius ervi. The latter attacks hosts that are able to actively defend themselves, and may thus indirectly influence patch time allocation of the parasitoid. Patch residence time decreased with an increase in temperature in both species. The increased activity levels with warming, as evidenced by the increase in walking speed, partially explained these variations, but other mechanisms were involved. In T. euproctidis, the ability to externally discriminate parasitised hosts decreased at low temperature, resulting in a longer patch residence time. Changes in sex allocation with temperature did not explain changes in patch time allocation in this species. For A. ervi, we observed that aphids frequently escaped at intermediate temperature and defended themselves aggressively at high temperature, but displayed few defence mechanisms at low temperature. These defensive behaviours resulted in a decreased patch residence time for the parasitoid and partly explained the fact that A. ervi remained for a shorter time at the intermediate and high temperatures than at the lowest temperature. Our results suggest that global warming may affect host-parasitoid interactions through complex mechanisms including both direct and indirect effects on parasitoid patch time allocation.

  12. Fort Sill Oklahoma/Post Field. Revised Uniform Summary of Surface Weather Observations

    DTIC Science & Technology

    1975-06-23

    uvious Willows ow Tnil bIA MI oIW U ~-A -- j f ;746 Y -imir,- 77---~ ( DATA PROCESSING qRAN;C4 1 ~ 1 C/UAF ERVIE/~AC INDSURFACE WINDSARWEATHER EVC /NA...PR "CESS.U 8Ak C ETAC/USAF- SURFACE WINDSAI ETE EVC /A ERETG RQEC FWN DIRECTION AND SPEED (FROM HOURLY OBSERVATIONS) 1J94 FidAT SILL QKLAIH0M4/P0ST FLO...FcIm An Iomei, -.1- 1 1; X. - ! ;; -~i m *v ’g. i DATA PRUCESSLMG BRAfCri USAF ETAC SIFMC CEILING VERSUS VISIBILITY AIR WEATHER EVC /A 13945 FORT SILL

  13. Reinnervation of Paralyzed Muscle by Nerve-Muscle-Endplate Band Grafting

    DTIC Science & Technology

    2015-10-01

    deficits. Plast Reconstr Surg. 2000;105(6):2003- 2009. 49. Goding GS Jr, Cummings CW, Bright DA. Extension of neuromuscular pedicles and direct nerve...Majed AA, Neumann CM, Brushart TM, Gordon T. Brief electrical stimulation promotes the speed and accuracy of motor axonal regeneration. J Neurosci... CT S.A. LeMaire, MD Editor of the Journal of Surgical Research Baylor College of Medicine, Houston, Texas, USA Dear Drs. McFadden and

  14. Learning to Lead: J. Lawton Collin’s Mastery of Large-Unit Command

    DTIC Science & Technology

    2015-05-21

    Approved for Public Release; Distribution is Unlimited Learning to Lead: J. Lawton Collins’ Mastery of Large- Unit Command A Monograph by MAJ...2. REPORT TYPE SAMS Monograph 3. DATES COVERED (From - To) Jun 2014-May 2015 4. TITLE AND SUBTITLE Learning to Lead: J. Lawton Collins’ Mastery...Name of Candidate: MAJ Alphonse J. LeMaire III Monograph Title: Learning to Lead: J. Lawton Collins’ Mastery of Large-Unit Command Approved by

  15. A Quantitative Methodology for Vetting Dark Network Intelligence Sources for Social Network Analysis

    DTIC Science & Technology

    2012-06-01

    introduced by Granovetter ( 1976 ) as a method to hurdle the requisite data collection efforts common to Social Network Analysis . His sampling method... 1976 ). Factor Regression Analysis : A New Method for Weighting Predictors. Defense Technical Information Center. de Leeuw, J., & Mair, P. (2009... ANALYSIS DISSERTATION James F. Morris AFIT/DS/ENS/12-05 The views expressed in this dissertation are those of the author and do not

  16. Development of Methodology and Technology for Identifying and Quantifying Emission Products from Open Burning and Open Detonation Thermal Treatment Methods. Bangbox Test Series. Volume 2. Test Development

    DTIC Science & Technology

    1992-01-01

    Mair.tenance Management Division Demilitarization and Technology Branch Rock Island, Illinois 61299-0t•00 S,3DSN: 79)-39•0o/,55 92313477 Commercial...Division, ELEMENT NO NO NO ACCESSION NO Dcmilita1izadon and’ Technology Branch Rnck ’sland. Illinnis 61299-6,00 I .TTLF (inLAude Security...Evaluation Branch , I Research Triangle Park, North Carolina. provided planning guidance, quality assurance/quality contro! support. and field and laboratory

  17. Adaptive evolution of a generalist parasitoid: implications for the effectiveness of biological control agents

    PubMed Central

    Zepeda-Paulo, Francisca A; Ortiz-Martínez, Sebastián A; Figueroa, Christian C; Lavandero, Blas

    2013-01-01

    The use of alternative hosts imposes divergent selection pressures on parasitoid populations. In response to selective pressures, these populations may follow different evolutionary trajectories. Divergent natural selection could promote local host adaptation in populations, translating into direct benefits for biological control, thereby increasing their effectiveness on the target host. Alternatively, adaptive phenotypic plasticity could be favored over local adaptation in temporal and spatially heterogeneous environments. We investigated the existence of local host adaptation in Aphidius ervi, an important biological control agent, by examining different traits related to infectivity (preference) and virulence (a proxy of parasitoid fitness) on different aphid-host species. The results showed significant differences in parasitoid infectivity on their natal host compared with the non-natal hosts. However, parasitoids showed a similar high fitness on both natal and non-natal hosts, thus supporting a lack of host adaptation in these introduced parasitoid populations. Our results highlight the role of phenotypic plasticity in fitness-related traits of parasitoids, enabling them to maximize fitness on alternative hosts. This could be used to increase the effectiveness of biological control. In addition, A. ervi females showed significant differences in infectivity and virulence across the tested host range, thus suggesting a possible host phylogeny effect for those traits. PMID:24062806

  18. Adaptive evolution of a generalist parasitoid: implications for the effectiveness of biological control agents.

    PubMed

    Zepeda-Paulo, Francisca A; Ortiz-Martínez, Sebastián A; Figueroa, Christian C; Lavandero, Blas

    2013-09-01

    The use of alternative hosts imposes divergent selection pressures on parasitoid populations. In response to selective pressures, these populations may follow different evolutionary trajectories. Divergent natural selection could promote local host adaptation in populations, translating into direct benefits for biological control, thereby increasing their effectiveness on the target host. Alternatively, adaptive phenotypic plasticity could be favored over local adaptation in temporal and spatially heterogeneous environments. We investigated the existence of local host adaptation in Aphidius ervi, an important biological control agent, by examining different traits related to infectivity (preference) and virulence (a proxy of parasitoid fitness) on different aphid-host species. The results showed significant differences in parasitoid infectivity on their natal host compared with the non-natal hosts. However, parasitoids showed a similar high fitness on both natal and non-natal hosts, thus supporting a lack of host adaptation in these introduced parasitoid populations. Our results highlight the role of phenotypic plasticity in fitness-related traits of parasitoids, enabling them to maximize fitness on alternative hosts. This could be used to increase the effectiveness of biological control. In addition, A. ervi females showed significant differences in infectivity and virulence across the tested host range, thus suggesting a possible host phylogeny effect for those traits.

  19. Protection of Pea Aphids Associated with Coinfecting Bacterial Symbionts Persists During Superparasitism by a Braconid Wasp.

    PubMed

    Donald, K J; Clarke, H V; Mitchell, C; Cornwell, R M; Hubbard, S F; Karley, A J

    2016-01-01

    Bacterial endosymbionts that associate facultatively with insect herbivores can influence insect fitness and trophic interactions. The pea aphid, Acyrthosiphon pisum, can be protected from parasitism by the braconid wasp Aphidius ervi when harbouring particular symbiotic bacteria, with specific endosymbiont coinfections providing almost complete protection. However, studies often quantify aphid mummification with no control over parasitoid oviposition per aphid; thus, if mummy production fails or is low, the causes are often unclear. Here, we show that the high level of protection associated with the coinfecting endosymbionts Hamiltonella defensa and X-type is maintained even when pea aphids are superparasitised. This contrasts strongly with the protection provided by H. defensa alone, which has been shown by others to be overcome by superparasitism. By dissecting aphids exposed to two parasitoid attacks, we reveal that A. ervi deposits eggs equally freely in endosymbiont-infected and uninfected nymphs, and lack of mummification in endosymbiont-protected nymphs arises from failure of the wasp eggs to hatch or emerging larvae to develop.

  20. Partial aphid resistance in lettuce negatively affects parasitoids.

    PubMed

    Lanteigne, Marie-Eve; Brodeur, Jacques; Jenni, Sylvie; Boivin, Guy

    2014-10-01

    This study investigated the effects of partial plant resistance on the lettuce aphid Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae), a major pest of cultivated lettuce (Lactuca sativa L.), and one of its parasitoids, Aphidius ervi Haliday (Hymenoptera: Braconidae). Aphids were reared on susceptible (L. sativa variety Estival; S) or partially resistant (Lactuca serriola L. PI 491093; PR) lettuce, and next parasitized by A. ervi females. Fitness proxies were measured for both aphids and parasitoids. Developmental time to adult stage took longer for alate and apterous aphids (an average of 3.5 and 1.5 additional days, respectively) on PR than on S lettuce, and fecundity of alate aphids reared on PR lettuce was reduced by 37.8% relative to those reared on S lettuce. Size (tibia length) and weight of aphids reared on PR lettuce were lower than for aphids reared on S lettuce from the third and second instar onward, respectively. Parasitism of aphids reared on PR plants resulted in lower parasitoid offspring emergence (-49.9%), lower adult female (-30.3%) and male (-27.5%) weight, smaller adult female (-17.5%) and male (-11.9%) size, and lower female fecundity (37.8% fewer eggs) than when parasitoids developed from aphids reared on S plants. Our results demonstrate that partial aphid resistance in lettuce negatively affects both the second and third trophic levels. Host plant resistance in cultivated lettuce may therefore create an ecological sink for aphid parasitoids.

  1. Tobacco overexpressing β-ocimene induces direct and indirect responses against aphids in receiver tomato plants.

    PubMed

    Cascone, Pasquale; Iodice, Luigi; Maffei, Massimo E; Bossi, Simone; Arimura, Gen-Ichiro; Guerrieri, Emilio

    2015-01-15

    In the last decade plant-to-plant communication has received an increasing attention, particularly for the role of Volatile Organic Compounds as possible elicitors of plant defense. The role of β-ocimene as an interspecific elicitor of plant defense has been recently assessed in multitrophic systems including different plant species (Solanaceae, Poaceae, legumes) and different pest species including chewer insects and phytophagous mites. Both chewer insects and phytophagous mites are known to elicit specific plant defensive pathways which are different (at least in part) from those elicited by sap feeders. The aim of this research was to fill this gap of knowledge and to assess the role of β-ocimene as an elicitor of plant defense against aphid pests, which are sap feeders. For this purpose we used as transgenic tobacco plant releasing an odour plume enriched in this compound as emitter and a tomato plant as receiver. We selected the aphid Macrosiphum euphorbiae and its natural enemy, the parasitoid Aphidius ervi, as the targets of plant induced defense. Tomato plant defense induced by β-ocimene was assessed by characterizing the aphid performance in terms of fixing behaviour, development and reproduction (direct plant defense) and the parasitoid performance in terms of attraction towards tomato plants (indirect plant defense). The characterization of tomato response to β-ocimene was completed by the identification of Volatile Organic Compounds as released by conditioned tomato plants. Tomato plants that were exposed to the volatiles of transgenic tobacco enriched in β-ocimene resulted in less suitable for the aphids in respect to control ones (direct defense). On tomato plants "elicited" by β-ocimene we recorded: a significant lower number of aphids settled; a significant lower number newborn nymphs; a significant lower weight of aphids feeding. In addition, tomato plants "elicited" by β-ocimene resulted became more attractive towards the parasitoid A. ervi

  2. Does sex-biased dispersal account for the lack of geographic and host-associated differentiation in introduced populations of an aphid parasitoid?

    PubMed

    Zepeda-Paulo, Francisca; Lavandero, Blas; Mahéo, Frédérique; Dion, Emilie; Outreman, Yannick; Simon, Jean-Christophe; Figueroa, Christian C

    2015-06-01

    Host recognition and use in female parasitoids strongly relies on host fidelity, a plastic behavior which can significantly restrict the host preferences of parasitoids, thus reducing the gene flow between parasitoid populations attacking different insect hosts. However, the effect of migrant males on the genetic differentiation of populations has been frequently ignored in parasitoids, despite its known impact on gene flow between populations. Hence, we studied the extent of gene flow mediated by female and male parasitoids by assessing sibship relationships among parasitoids within and between populations, and its impact on geographic and host-associated differentiation in the aphid parasitoid Aphidius ervi. We report evidences of a high gene flow among parasitoid populations on different aphid hosts and geographic locations. The high gene flow among parasitoid populations was found to be largely male mediated, suggested by significant differences in the distribution of full-sib and paternal half-sib dyads of parasitoid populations.

  3. Does sex-biased dispersal account for the lack of geographic and host-associated differentiation in introduced populations of an aphid parasitoid?

    PubMed Central

    Zepeda-Paulo, Francisca; Lavandero, Blas; Mahéo, Frédérique; Dion, Emilie; Outreman, Yannick; Simon, Jean-Christophe; Figueroa, Christian C

    2015-01-01

    Host recognition and use in female parasitoids strongly relies on host fidelity, a plastic behavior which can significantly restrict the host preferences of parasitoids, thus reducing the gene flow between parasitoid populations attacking different insect hosts. However, the effect of migrant males on the genetic differentiation of populations has been frequently ignored in parasitoids, despite its known impact on gene flow between populations. Hence, we studied the extent of gene flow mediated by female and male parasitoids by assessing sibship relationships among parasitoids within and between populations, and its impact on geographic and host-associated differentiation in the aphid parasitoid Aphidius ervi. We report evidences of a high gene flow among parasitoid populations on different aphid hosts and geographic locations. The high gene flow among parasitoid populations was found to be largely male mediated, suggested by significant differences in the distribution of full-sib and paternal half-sib dyads of parasitoid populations. PMID:26078852

  4. Aphid-encoded variability in susceptibility to a parasitoid

    PubMed Central

    2014-01-01

    Background Many animals exhibit variation in resistance to specific natural enemies. Such variation may be encoded in their genomes or derived from infection with protective symbionts. The pea aphid, Acyrthosiphon pisum, for example, exhibits tremendous variation in susceptibility to a common natural enemy, the parasitic wasp Aphidius ervi. Pea aphids are often infected with the heritable bacterial symbiont, Hamiltonella defensa, which confers partial to complete resistance against this parasitoid depending on bacterial strain and associated bacteriophages. That previous studies found that pea aphids without H. defensa (or other symbionts) were generally susceptible to parasitism, together with observations of a limited encapsulation response, suggested that pea aphids largely rely on infection with H. defensa for protection against parasitoids. However, the limited number of uninfected clones previously examined, and our recent report of two symbiont-free resistant clones, led us to explicitly examine aphid-encoded variability in resistance to parasitoids. Results After rigorous screening for known and unknown symbionts, and microsatellite genotyping to confirm clonal identity, we conducted parasitism assays using fifteen clonal pea aphid lines. We recovered significant variability in aphid-encoded resistance, with variation levels comparable to that contributed by H. defensa. Because resistance can be costly, we also measured aphid longevity and cumulative fecundity of the most and least resistant aphid lines under permissive conditions, but found no trade-offs between higher resistance and these fitness parameters. Conclusions These results indicate that pea aphid resistance to A. ervi is more complex than previously appreciated, and that aphids employ multiple tactics to aid in their defense. While we did not detect a tradeoff, these may become apparent under stressful conditions or when resistant and susceptible aphids are in direct competition. Understanding

  5. Primary and secondary parasitoids (Hymenoptera) of aphids (Hemiptera: Aphididae) on blueberry and other Vaccinium in the Pacific Northwest.

    PubMed

    Raworth, D A; Pike, K S; Tanigoshi, L K; Mathur, S; Graf, G

    2008-04-01

    Blueberry scorch virus, a commercially important Carlavirus in highbush blueberry, Vaccinium corymbosum L., is vectored by aphids (Hemiptera: Aphididae). We surveyed the aphids, primary parasitoids (Hymenoptera: Aphelinidae, Braconidae), and associated secondary parasitoids (Hymenoptera: Charipidae, Megaspilidae, Pteromalidae) on highbush blueberry and other Vaccinium in the Pacific Northwest from 1995 to 2006, with samples concentrated in 2005 and 2006, to lay the groundwork for augmentative biological control. Ericaphis fimbriata (Richards) was the principal aphid. The dominant parasitoid species were Praon unicum Smith, Aphidius n. sp., A. sp., and Aphidius ervi Haliday. Their frequency in relation to the other primary parasitoids varied significantly with geographical area; P. unicum dominated the frequency distribution in southwestern British Columbia, A. n. sp., west of the Cascades, and A. sp. and A. ervi east of the Cascades. Among the secondary parasitoids, pteromalids dominated, and their frequency in relation to the other secondary parasitoids was lowest in southwestern British Columbia. The parasitization rate for P. unicum and A. n. sp. in southwestern British Columbia increased from May or June to a maximum of 0.080 +/- 0.024 and 0.090 +/- 0.084 (SD), respectively, in late July or early August. P. unicum emerged in the spring 4 wk before A. n. sp. The parasitization rate for P. unicum was lower in conventional than organic fields. Whereas aphid density increased monotonically, P. unicum had two spring peaks. A simulation model showed that these peaks could reflect discrete generations. Releases of insectary-reared P. unicum at 150 or 450 DD above 5.6 degrees C, summing from 1 January, may effectively augment the natural spring populations by creating overlapping generations.

  6. Analog earthquakes: Friction experiments with bulk solids and implications for fault dynamics

    NASA Astrophysics Data System (ADS)

    Rosenau, M.; Klinkmueller, M.; Oppelt, A.; Kemnitz, H.; Oncken, O.; Schreurs, G.

    2008-12-01

    We report on friction experiments on dry bulk solids used to simulate slow ("aseismic") and fast ("seismic") slip in analog laboratory experiments. Ring shear tests have been performed at typical experimental conditions, i.e. in the very low stress regime (normal loads < 0.02 MPa, shear velocities 0.05 - 25 mm/min, T = 23°), and compared to similar tests at higher stresses (Mair and Marone 1999; Mair et al., 2002). Friction tests have been complemented with scanning electron microscope analysis to explore the control of particle characteristics (size, shape, sorting, roughness) on the strength and stability of frictional deformation. By varying the ratio between particle size and displacement we aim at simulating different brittle deformation mechanisms: Fine-grained material (sand, glass beads, sugar, salt) exposed to relatively fast shear undergoes distributed granular flow (DGF) including particle rotation, dilation and sliding. Rather slow shear of coarse material (rice) is accommodated mainly by localized particle boundary sliding (LBS). Both mechanisms are capable to produce frictional instabilities resulting in stick-slip motion. We found that frictional strength during DGF is controlled by particle shape: the frictional coefficient increases with the amount of angular particles consistent with previous findings by Mair et al. (2002) in the high stress regime (> 5 MPa). Also consistent with their work, unstable slip during DGF occurs if well-sorted and isometric particles dominate presumably controlled by the breakdown of force bridges. Frictional strength and stability during LBS seems to be controlled by surface roughness consistent with the concept of asperities. For particle surfaces with a scale-invariant roughness similar to natural faults, the critical distance over which slip has to accelerate to become unstable is not constant but increases with "interseismic" sliding velocity both during LBS (this study) and DGF (Mair and Marone, 1999). We found

  7. Robins AFB, Warner Robins, Georgia. Revised Uniform Summary of Surface Weather Observations (RUSSWO). Parts A-F

    DTIC Science & Technology

    1979-08-31

    73 - FED 79 POR FROM DAILY OBS: MAIR 49 - FEB 79 - AUG 3 11979- j FEDERAL BUILDING ASHEVILLE, N. C . - t~ 10 02 057j$9.tO J" *~-X* 33,... *,i 7...IZY WOflOS ( C oiliu ove.’o old. It . coory and lIdentify by block Ooosb.r)- *RUSSWO Daily temperature Atmospheric pressure Snowfall Extreme Snow depth...Phenomena; (8) Precipitation, Snowfall and Snow Depth (daily amounts and extreme values); ( C ) Surface winds; (D) Ceiling Versus Visibility; Sky Cover; (E

  8. Dominant gene for rust resistance in pearl millet

    SciTech Connect

    Hanna, W.W.; Wells, H.D.; Burton, G.W.

    1985-01-01

    Rust (Puccinia substriata var. indica) resistance was discovered in three Pennisetum americanum (L.) Leeke subspecies monodii (Maire) Brunken accessions from Senegal. Resistant plant were free of rust, although the bottom one or two leaves of some plants did develop a brown discoloration without pustules. Resistance was controlled by a dominant gene assigned the gene symbol Rr1. Backcrossing has been effective in transferring resistance from the wild grassy, monodii to cultivated pearl millet. The Rr1 gene should be useful in the production of rust resistant pearl millet hybrids and cultivars. 6 references, 1 table.

  9. International Conference on Photochemistry (15th) Abstracts of Invited Lectures and Oral and Poster Contributions Held in Paris, France on 28 July-2 August 1991 (XVeme Conference Internationale de Photochimie, Paris, France 28 Juillet-2 Aout 1991)

    DTIC Science & Technology

    1991-08-01

    RICIHARD and Pierre BDOULC Laboratolre de Photochimie 1ol6culalre et Hacromolculalire, Uh CHRS 433, Universit Blaise Pascal (Clermont-Ferrand), F...PROCESSES IN SATURAiLE DYES STUDIED BY TIME RESOLVED SPECTROSCOPY Monique M. MARTIN, Pascal PLAZA, Nguyen DAI HUNG, Yves i1. MEYER Laboratoire dc...CONFOIINATIONNELLEH ULT’RARAPI)E D)ES COLORANTS SATURAIILES ET’UIEI P’AR SPEVUEROSCOPIE RESOLUI’ EN TEMI’S Monique M. MAirIN, Pascal PLAZA, Nguyen DAI I UNG

  10. A new schematic for poly(3-alkylthiophene) in an amorphous film studied using a novel structural index in infrared spectroscopy.

    PubMed

    Shioya, N; Shimoaka, T; Eda, K; Hasegawa, T

    2015-05-28

    The molecular structure of poly(3-alkylthiophene-2,5-diyl) in an amorphous film reveals that the short axis of the thiophene ring is kept highly oriented parallel to the substrate, whereas the long axis along the polymer chain is largely disordered. This is unveiled by infrared p-polarized multiple-angle incidence resolution spectroscopy (pMAIRS), achieved by analyzing the orientation angles of three mutually orthogonal vibrational modes localized on the thiophene ring with the aid of a newly developed structural index. This new analytical technique is useful irrespective of the crystallinity of the thin film. As a result, the intrinsic chemical parameters controlling the molecular orientation are understood in a unified manner, and the reason that the hexyl group gives the best results for a photovoltaic cell is also revealed.

  11. Closed form analysis of a gamma, back-to-back free displacer Stirling engine

    SciTech Connect

    Lewis, K.L.; Kilgour, D.B.; Lazarides, Y.G.; Rallis, C.J.

    1983-08-01

    A back-to-back, free displacer, gamma type Stirling engine has been designed and is currently under manufacture and development at the University of the Witwatersrand. This paper presents a simple idealized analysis for such an engine. It involves the coupling together of the thermodynamic and mechanical equations, and by the use of classical control and vibration theory, closed form solutions are obtained. This work follows up on previous methods of analysis developed by Berchowitz, WyattMair and Goldberg for similar types of engines. A numerical application of the analysis has been carried out for the design in order to evaluate the operating frequency, phase displacements, amplitude of oscillation and basic output power. Performance characteristics are obtained and detailed in the paper. The analysis has provided analytic proof of the viability of the proposed engine configuration, highlighted weak areas and provided a background to higher order analysis. A programme of experimental validation is under way.

  12. Mediation and causality at the individual level.

    PubMed

    Bergman, Lars R

    2009-09-01

    Within a person-oriented research paradigm the focus is on individuals characterized by patterns of information that are regarded as indivisible wholes. It is then not sufficient to carry out standard variable-oriented mediation analysis. The procedure suggested by von Eye, Mun, and Mair (2009) for pattern-oriented mediation analysis is much better aligned to this person-oriented framework. An important new feature in their approach is that it can detect mediator configurations that prohibit predictor and outcome connections at a pattern level. Two extensions of their procedure are suggested, namely (1) the use of cluster analysis to arrive at the categories and (2) the use of other models for estimating the expected frequencies. It is pointed out that in their context a functional relations perspective might be more relevant than the standard causality perspective.

  13. Surface proton transport of fully protonated poly(aspartic acid) thin films on quartz substrates

    NASA Astrophysics Data System (ADS)

    Nagao, Yuki; Kubo, Takahiro

    2014-12-01

    Thin film structure and the proton transport property of fully protonated poly(aspartic acid) (P-Asp100) have been investigated. An earlier study assessed partially protonated poly(aspartic acid), highly oriented thin film structure and enhancement of the internal proton transport. In this study of P-Asp100, IR p-polarized multiple-angle incidence resolution (P-MAIR) spectra were measured to investigate the thin film structure. The obtained thin films, with thicknesses of 120-670 nm, had no oriented structure. Relative humidity dependence of the resistance, proton conductivity, and normalized resistance were examined to ascertain the proton transport property of P-Asp100 thin films. The obtained data showed that the proton transport of P-Asp100 thin films might occur on the surface, not inside of the thin film. This phenomenon might be related with the proton transport of the biological system.

  14. A numerical taxonomic study of Actinobacillus, Pasteurella and Yersinia.

    PubMed

    Sneath, P H; Stevens, M

    1985-10-01

    A numerical taxonomic study of strains of Actinobacillus, Pasteurella and Yersinia, with some allied bacteria, showed 23 reasonably distinct groups. These fell into three major areas. Area A contained species of Actinobacillus and Pasteurella: A. suis, A. equuli, A. lignieresii, P. haemolytica biovar A, P. haemolytica biovar T, P. multocida, A. actinomycetemcomitans, 'P. bettii', 'A. seminis', P. ureae and P. aerogenes. Also included in A was a composite group of Pasteurella pneumotropica and P. gallinarum, together with unnamed groups referred to as 'BLG', 'Mair', 'Ross' and 'aer-2'. Area B contained species of Yersinia: Y. enterocolitica, Y. pseudotuberculosis, Y. pestis and a group 'ent-b' similar to Y. enterocolitica. Area C contained non-fermenting strains: Y. philomiragia, Moraxella anatipestifer and a miscellaneous group 'past-b'. There were also a small number of unnamed single strains.

  15. Climate Change Studies over Bangalore using Multi-source Remote Sensing Data and GIS

    NASA Astrophysics Data System (ADS)

    B, S.; Gouda, K. C.; Laxmikantha, B. P.; Bhat, N.

    2014-12-01

    Urbanization is a form of metropolitan growth that is a response to often bewildering sets of economic, social, and political forces and to the physical geography of an area. Some of the causes of the sprawl include - population growth, economy, patterns of infrastructure initiatives like the construction of roads and the provision of infrastructure using public money encouraging development. The direct implication of such urban sprawl is the change in land use and land cover of the region. In this study the long term climate data from multiple sources like NCEP reanalysis, IMD observations and various satellite derived products from MAIRS, IMD, ERSL and TRMM are considered and analyzed using the developed algorithms for the better understanding of the variability in the climate parameters over Bangalore. These products are further mathematically analyzed to arrive at desired results by extracting land surface temperature (LST), Potential evapo-transmission (PET), Rainfall, Humidity etc. Various satellites products are derived from NASA (National Aeronautics Space Agency), Indian meteorological satellites and global satellites are helpful in massive study of urban issues at global and regional scale. Climate change analysis is well studied by using either single source data such as Temperature or Rainfall from IMD (Indian Meteorological Department) or combined data products available as in case of MAIRS (Monsoon Asia Integrated Regional Scale) program to get rainfall at regional scale. Finally all the above said parameters are normalized and analyzed with the help of various open source available software's for pre and post processing our requirements to obtain desired results. A sample of analysis i.e. the Inter annual variability of annual averaged Temperature over Bangalore is presented in figure 1, which clearly shows the rising trend of the temperature (0.06oC/year). Also the Land use and land cover (LULC) analysis over Bangalore, Day light hours from

  16. The heuristic value of redundancy models of aging.

    PubMed

    Boonekamp, Jelle J; Briga, Michael; Verhulst, Simon

    2015-11-01

    Molecular studies of aging aim to unravel the cause(s) of aging bottom-up, but linking these mechanisms to organismal level processes remains a challenge. We propose that complementary top-down data-directed modelling of organismal level empirical findings may contribute to developing these links. To this end, we explore the heuristic value of redundancy models of aging to develop a deeper insight into the mechanisms causing variation in senescence and lifespan. We start by showing (i) how different redundancy model parameters affect projected aging and mortality, and (ii) how variation in redundancy model parameters relates to variation in parameters of the Gompertz equation. Lifestyle changes or medical interventions during life can modify mortality rate, and we investigate (iii) how interventions that change specific redundancy parameters within the model affect subsequent mortality and actuarial senescence. Lastly, as an example of data-directed modelling and the insights that can be gained from this, (iv) we fit a redundancy model to mortality patterns observed by Mair et al. (2003; Science 301: 1731-1733) in Drosophila that were subjected to dietary restriction and temperature manipulations. Mair et al. found that dietary restriction instantaneously reduced mortality rate without affecting aging, while temperature manipulations had more transient effects on mortality rate and did affect aging. We show that after adjusting model parameters the redundancy model describes both effects well, and a comparison of the parameter values yields a deeper insight in the mechanisms causing these contrasting effects. We see replacement of the redundancy model parameters by more detailed sub-models of these parameters as a next step in linking demographic patterns to underlying molecular mechanisms.

  17. Mechanisms for stable coexistence in an insect community.

    PubMed

    Fan, Meng; Zhang, Bingbing; Li, Michael Yi

    2010-07-01

    In this paper, we formulate a three-species ecological community model consisting of two aphid species (Acyrthosiphon pisum and Megoura viciae) and a specialist parasitoid (Aphidius ervi) that attacks only one of the aphids (A pisum). The model incorporates both density-mediated and trait-mediated host-parasitoid interactions. Our analysis shows that the model possesses much richer and more realistic dynamics than earlier models. Our theoretical results reveal a new mechanism for stable coexistence in a three-species community in which any two species alone do not co-exist. More specifically, it is known that, when a predator is introduced into a community of two competing species, if the predator only predates on the strong competitor, it can allow the weak competitor to survive, but may drive the strong competitor to extinction through over-exploitation. We show that if the weak competitor interferes the predation on the strong competitor through trait-mediated indirect effects, then all three species can stably co-exist.

  18. Covariance of phenotypically plastic traits induces an adaptive shift in host selection behaviour

    PubMed Central

    Henry, Lee M; Roitberg, Bernard D; Gillespie, David R

    2006-01-01

    Flexibility in adult body size allows generalist parasitoids to use many host species at a cost of producing a range of adult sizes. Consequently, host selection behaviour must also maintain a level of flexibility as adult size is related to capture efficiency. In the present study, we investigated covariance of two plastic traits—size at pupation and host size selection behaviour—using Aphidius ervi reared on either Acyrthosiphon pisum or Aulacorthum solani, generating females of disparate sizes. Natal host was shown to change the ranking of perceived host quality with relation to host size. Parasitoids preferentially attacked hosts that corresponded to the size of the second instar of their natal host species. This resulted in optimal host selection behaviour when parasitoids were exposed to the same host species from which they emerged. Parasitoid size was positively correlated with host size preference, indicating that females use relative measurements when selecting suitable hosts. These coadapted gene complexes allow generalist parasitoids to effectively use multiple host species over several generations. However, the fixed nature of the behavioural response, within a parasitoid's lifetime, suggests that these traits may have evolved in a patchy host species environment. PMID:17015365

  19. A facultative endosymbiont in aphids can provide diverse ecological benefits.

    PubMed

    Heyworth, E R; Ferrari, J

    2015-10-01

    Ecologically important traits of insects are often affected by facultative bacterial endosymbionts. This is best studied in the pea aphid Acyrthosiphon pisum, which is frequently infected by one or more of eight facultative symbiont species. Many of these symbiont species have been shown to provide one ecological benefit, but we have little understanding of the range of effects that a single strain can have. Here, we describe the phenotypes conferred by three strains of the recently discovered bacterium known as X-type (Enterobacteriaceae), each in their original aphid genotype which also carries a Spiroplasma symbiont. All comparisons are made between aphids that are coinfected with Spiroplasma and X-type and aphids of the same genotype that harbour only Spiroplasma. We show that in all cases, infection with X-type protects aphids from the lethal fungal pathogen Pandora neoaphidis, and in two cases, resistance to the parasitoid Aphidius ervi also increases. X-type can additionally affect aphid stress responses--the presence of X-type increased reproduction after the aphids were heat-stressed. Two of the three strains of X-type are able to provide all of these benefits. Under benign conditions, the aphids tended to suffer from reduced fecundity when harbouring X-type, a mechanism that might maintain intermediate frequencies in field populations. These findings highlight that a single strain of a facultative endosymbiont has the potential to provide diverse benefits to its aphid host.

  20. Facultative bacterial symbionts in aphids confer resistance to parasitic wasps

    PubMed Central

    Oliver, Kerry M.; Russell, Jacob A.; Moran, Nancy A.; Hunter, Martha S.

    2003-01-01

    Symbiotic relationships between animals and microorganisms are common in nature, yet the factors controlling the abundance and distributions of symbionts are mostly unknown. Aphids have an obligate association with the bacterium Buchnera aphidicola (the primary symbiont) that has been shown to contribute directly to aphid fitness. In addition, aphids sometimes harbor other vertically transmitted bacteria (secondary symbionts), for which few benefits of infection have been previously documented. We carried out experiments to determine the consequences of these facultative symbioses in Acyrthosiphon pisum (the pea aphid) for vulnerability of the aphid host to a hymenopteran parasitoid, Aphidius ervi, a major natural enemy in field populations. Our results show that, in a controlled genetic background, infection confers resistance to parasitoid attack by causing high mortality of developing parasitoid larvae. Compared with uninfected controls, experimentally infected aphids were as likely to be attacked by ovipositing parasitoids but less likely to support parasitoid development. This strong interaction between a symbiotic bacterium and a host natural enemy provides a mechanism for the persistence and spread of symbiotic bacteria. PMID:12563031

  1. Evidence for specificity in symbiont-conferred protection against parasitoids

    PubMed Central

    McLean, Ailsa H. C.; Godfray, H. Charles J.

    2015-01-01

    Many insects harbour facultative symbiotic bacteria, some of which have been shown to provide resistance against natural enemies. One of the best-known protective symbionts is Hamiltonella defensa, which in pea aphid (Acyrthosiphon pisum) confers resistance against attack by parasitoid wasps in the genus Aphidius (Braconidae). We asked (i) whether this symbiont also confers protection against a phylogenetically distant group of parasitoids (Aphelinidae) and (ii) whether there are consistent differences in the effects of bacteria found in pea aphid biotypes adapted to different host plants. We found that some H. defensa strains do provide protection against an aphelinid parasitoid Aphelinus abdominalis. Hamiltonella defensa from the Lotus biotype provided high resistance to A. abdominalis and moderate to low resistance to Aphidius ervi, while the reverse was seen from Medicago biotype isolates. Aphids from Ononis showed no evidence of symbiont-mediated protection against either wasp species and were relatively vulnerable to both. Our results may reflect the different selection pressures exerted by the parasitoid community on aphids feeding on different host plants, and could help explain the maintenance of genetic diversity in bacterial symbionts. PMID:26136451

  2. Shallot aphids, Myzus ascalonicus, in strawberry: biocontrol potential of three predators and three parasitoids.

    PubMed

    Enkegaard, Annie; Sigsgaard, Lene; Kristensen, Kristian

    2013-01-01

    The parasitization capacity of 3 parasitoids and the predation capacity of 3 predators towards the shallot aphid, Myzus ascalonicus Doncaster (Homoptera: Aphididae), on strawberry, Fragaria x ananassa Duchesne (Rosales: Rosaceae) cv. Honeoye, were examined in laboratory experiments. In Petri dish assays, both Aphidius colemani Viereck (Hymenoptera: Aphidiidae) and A. ervi Haliday readily stung shallot aphids, with no significant difference in stinging frequency between the two species. A. ervi induced a significantly higher mortality (79.0 ± 7.2%) in terms of stung aphids compared with A. colemani (55.3 ± 4.1%); however, only a minor fraction (2.7 ± 1.8% and 7.1 ± 3.1%, respectively) of the killed aphids resulted in formation of mummies, presumably due to a physiological response to parasitism. The low percentage of mummification precludes the use of either Aphidius species in anything but inundative biocontrol. In similar set-ups, Aphelinus abdominalis (Dalman) (Hymenoptera: Aphelinidae) killed almost half (49.6 ± 5.3%) of the exposed aphids through host feeding. In addition, 23.2 ± 7.3% of non-host-fed aphids developed into mummified aphids, and 38.1 ± 13.2% of non-host-fed aphids died from other parasitoid-induced causes. However, the host feeding rate was reduced to only 1.2 ± 0.8%, and no significant parasitization mortality was observed on strawberry plants, suggesting that host plants interfered with A. abdominalis activity. This parasitoid does not, therefore, seem to be suited to either inoculative or inundative biocontrol of shallot aphids in strawberry. The three predators studied were the green lacewing, Chrysoperla carnea Steph. (Neuroptera: Chrysopidae), the two-spotted lady beetle, Adalia bipunctata L. (Coleoptera: Coccinellidae), and the gall midge Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae). Third instars of all 3 predators readily preyed upon the shallot aphid in Petri dish set-ups with significant differences in daily

  3. Endotoxin removal by radio frequency gas plasma (glow discharge)

    NASA Astrophysics Data System (ADS)

    Poon, Angela

    2011-12-01

    Contaminants remaining on implantable medical devices, even following sterilization, include dangerous fever-causing residues of the outer lipopolysaccharide-rich membranes of Gram-negative bacteria such as the common gut microorganism E. coli. The conventional method for endotoxin removal is by Food & Drug Administration (FDA)-recommended dry-heat depyrogenation at 250°C for at least 45 minutes, an excessively time-consuming high-temperature technique not suitable for low-melting or heat-distortable biomaterials. This investigation evaluated the mechanism by which E. coli endotoxin contamination can be eliminated from surfaces during ambient temperature single 3-minute to cumulative 15-minute exposures to radio-frequency glow discharge (RFGD)-generated residual room air plasmas activated at 0.1-0.2 torr in a 35MHz electrodeless chamber. The main analytical technique for retained pyrogenic bio-activity was the Kinetic Chromogenic Limulus Amebocyte Lysate (LAL) Assay, sufficiently sensitive to document compliance with FDA-required Endotoxin Unit (EU) titers less than 20 EU per medical device by optical detection of enzymatic color development corresponding to < 0.5 EU/ml in sterile water extracts of each device. The main analytical technique for identification of chemical compositions, amounts, and changes during sequential reference Endotoxin additions and subsequent RFGD-treatment removals from infrared (IR)-transparent germanium (Ge) prisms was Multiple Attenuated Internal Reflection (MAIR) infrared spectroscopy sensitive to even monolayer amounts of retained bio-contaminant. KimaxRTM 60 mm x 15 mm and 50mm x 15mm laboratory glass dishes and germanium internal reflection prisms were inoculated with E. coli bacterial endotoxin water suspensions at increments of 0.005, 0.05, 0.5, and 5 EU, and characterized by MAIR-IR spectroscopy of the dried residues on the Ge prisms and LAL Assay of sterile water extracts from both glass and Ge specimens. The Ge prism MAIR

  4. Multitrophic interactions involving genetically modified potatoes, nontarget aphids, natural enemies and hyperparasitoids.

    PubMed

    Cowgill, S E; Danks, C; Atkinson, H J

    2004-03-01

    Genetically modified (GM) potatoes expressing a cysteine proteinase inhibitor (cystatin) have been developed as an option for the management of plant parasitic nematodes. The relative impact of such plants on predators and parasitoids (natural enemies) of nontarget insects was determined in a field trial. The trial consisted of GM plants, control plants grown in soil treated with a nematicide and untreated control plants. The quantity of nontarget aphids and their quality as hosts for natural enemies were studied. Aphid density was significantly reduced by nematicide treatment and few natural enemies were recorded from treated potatoes during the study. In contrast, similar numbers of aphids and their more abundant predators were recorded from the untreated control and the GM potatoes. The size of aphids on GM and control plants was recorded twice during the study. During the first sampling period (2-9 July) aphids clip-caged on GM plants were smaller than those on control plants. During the second sampling period (23-30 July) there was no difference in aphid size between those from the GM and control plants. Host size is an important component of host quality. It can affect the size and fecundity of parasitoid females and the sex ratio of their offspring. However, neither the fitness of females of Aphidius ervi, the most prevalent primary parasitoid, nor the sex ratio of their progeny, were affected when the parasitoids developed on aphids feeding on GM plants. Two guilds of secondary parasitoid were also recorded during the study. The fitness of the most abundant species, Aspahes vulgaris, was not affected when it developed on hosts from GM plants. The transgene product, OC I Delta D86, was not detected in aphids that had fed on GM plants in the field, suggesting that there is minimal secondary exposure of natural enemies to the inhibitor. The results indicate that transgenic nematode resistance is potentially more compatible with aphid biological control than is

  5. Heavy Metal Pollution in Urban Soils of Sopron

    NASA Astrophysics Data System (ADS)

    Horváth, Adrienn; Bidló, András

    2014-05-01

    Keywords: anthropogenic effects, land use types, heavy metal content, polluted urban soils, GIS methods Our aim was to identify the main feedback effects between the town and its environment. In the course of our investigation we have analysed the heavy metal contents of urban soil in Sopron town in Hungary. We collected 208 samples on 104 points from 0 to 10 and from 10 to 20 cm depth in a standard network and also at industrial territories. We have been represented our results in a GIS system. We analysed the soils with Lakanen-Erviö method and we measured 24 elements but we have been focused on Co, Cd, Cu, Pb and Zn. Using the data we observed the relationship between these elements in both layers. In the downtown the acidity of soils were alkaline by the greatest number of point, therefore the pollution of these soils is not leach in deeper layers yet. The lead was very high (> 100 mg Pb/kg) in both layers on the whole area of the town. Urban soils with high copper content (among 611 mg and 1221 mg Cu/kg) have been collected from garden and viticulture areas by us. Cadmium contents were the highest (6.14 mg Cd/kg) in traffic zones, where these values could be more than 3 mg Cd/kg according to the literature. The cobalt and zinc results were under the limits. According to our measurements we founded the highest average values in the soils of parks. This could be contamination of the lead from traffic, which bind in the soil of urban green spaces. Now we could continue our examinations with the investigations of these polluted green areas, which can effect to human health.

  6. Deriving leaf chlorophyll content of green-leafy vegetables from hyperspectral reflectance

    NASA Astrophysics Data System (ADS)

    Xue, Lihong; Yang, Linzhang

    Different nitrogen (N) treatments of four common green-leafy vegetable varieties with different leaf color: lettuce ( Lactuca sativa L. var. crispa L.) with yellow green leaves, pakchoi ( Brassica chinensis L.) var. aijiaohuang in Chinese (AJH) with middle green leaves, spinach ( Spinacia oleracea L.) with green leaves and pakchoi ( B. chinensis L.) var. shanghaiqing in Chinese (SHQ) with dark green leaves, were carried out to achieve a wide range of chlorophyll content. The relationship of vegetable leaf hyperspectral response to its chlorophyll content was examined in this study. Almost all reported successful leaf chlorophyll indices in the literature were evaluated for their ability to predict the chlorophyll content in vegetable leaves. Some new indices based on the first derivative curve were also developed, and compared with the chlorophyll indices published. The results showed that most of the indices showed a strong relation with leaf chlorophyll content. In general, modified indices with the blue or near red edge wavelength performed better than their simple counterpart without modification, ratio indices performed a little better than normalized indices when chlorophyll expressed on area basis and reversed when chlorophyll expressed on fresh weight basis. A normalized derivative difference ratio (BND: (D722-D700)/(D722+D700) calibrated by Maire et al. [Maire, G., Francois, C., Dufrene, E., 2004. Towards universal broad leaf chlorophyll indices using PROSPECT simulated database and hyperspectral reflectance measurements. Remote Sensing of Environment 89 (1), 1-28]) gave the best results among all published indices in this study (RMSE=22.1 mg m -2), then the mSR-like indices with the RMSE between 22.6 and 23.0 mg m -2. The new indices EBAR (ratio of the area of red and blue, ∑ dRE/∑ dB), EBFN (normalized difference of the amplitude of red and blue, (dRE-dB)/(dRE+dB)) and EBAN (normalized difference of the area of red and blue, (∑ dRE-∑ dB)/(∑ d

  7. Exploring Remote Sensing Products Online with Giovanni for Studying Urbanization

    NASA Technical Reports Server (NTRS)

    Shen, Suhung; Leptoukh, Gregory G.; Gerasimov, Irina; Kempler, Steve

    2012-01-01

    Recently, a Large amount of MODIS land products at multi-spatial resolutions have been integrated into the online system, Giovanni, to support studies on land cover and land use changes focused on Northern Eurasia and Monsoon Asia regions. Giovanni (Goddard Interactive Online Visualization ANd aNalysis Infrastructure) is a Web-based application developed by the NASA Goddard Earth Sciences Data and Information Services Center (GES-DISC) providing a simple and intuitive way to visualize, analyze, and access Earth science remotely-sensed and modeled data. The customized Giovanni Web portals (Giovanni-NEESPI and Giovanni-MAIRS) are created to integrate land, atmospheric, cryospheric, and social products, that enable researchers to do quick exploration and basic analyses of land surface changes and their relationships to climate at global and regional scales. This presentation documents MODIS land surface products in Giovanni system. As examples, images and statistical analysis results on land surface and local climate changes associated with urbanization over Yangtze River Delta region, China, using data in Giovanni are shown.

  8. Visualization and Analysis of Multi-scale Land Surface Products via Giovanni Portals

    NASA Technical Reports Server (NTRS)

    Shen, Suhung; Kempler, Steven J.; Gerasimov, Irina V.

    2013-01-01

    Large volumes of MODIS land data products at multiple spatial resolutions have been integrated into the Giovanni online analysis system to support studies on land cover and land use changes,focused on the Northern Eurasia and Monsoon Asia regions through the LCLUC program. Giovanni (Goddard Interactive Online Visualization ANd aNalysis Infrastructure) is a Web-based application developed by the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC), providing a simple and intuitive way to visualize, analyze, and access Earth science remotely-sensed and modeled data.Customized Giovanni Web portals (Giovanni-NEESPI andGiovanni-MAIRS) have been created to integrate land, atmospheric,cryospheric, and societal products, enabling researchers to do quick exploration and basic analyses of land surface changes, and their relationships to climate, at global and regional scales. This presentation shows a sample Giovanni portal page, lists selected data products in the system, and illustrates potential analyses with imagesand time-series at global and regional scales, focusing on climatology and anomaly analysis. More information is available at the GES DISCMAIRS data support project portal: http:disc.sci.gsfc.nasa.govmairs.

  9. Analysis of Vegetation Index Variations and the Asian Monsoon Climate

    NASA Technical Reports Server (NTRS)

    Shen, Sunhung; Leptoukh, Gregory G.; Gerasimov, Irina

    2012-01-01

    Vegetation growth depends on local climate. Significant anthropogenic land cover and land use change activities over Asia have changed vegetation distribution as well. On the other hand, vegetation is one of the important land surface variables that influence the Asian Monsoon variability through controlling atmospheric energy and water vapor conditions. In this presentation, the mean and variations of vegetation index of last decade at regional scale resolution (5km and higher) from MODIS have been analyzed. Results indicate that the vegetation index has been reduced significantly during last decade over fast urbanization areas in east China, such as Yangtze River Delta, where local surface temperatures were increased significantly in term of urban heat Island. The relationship between vegetation Index and climate (surface temperature, precipitation) over a grassland in northern Asia and over a woody savannas in southeast Asia are studied. In supporting Monsoon Asian Integrated Regional Study (MAIRS) program, the data in this study have been integrated into Giovanni, the online visualization and analysis system at NASA GES DISC. Most images in this presentation are generated from Giovanni system.

  10. Fluid management in traumatic shock: a practical approach for mountain rescue. Official recommendations of the International Commission for Mountain Emergency Medicine (ICAR MEDCOM).

    PubMed

    Sumann, Günther; Paal, Peter; Mair, Peter; Ellerton, John; Dahlberg, Tore; Zen-Ruffinen, Gregoire; Zafren, Ken; Brugger, Hermann

    2009-01-01

    Sumann, Günther, Peter Paal, Peter Mair, John Ellerton, Tore Dahlberg, Gregoire Zen-Ruffinen, Ken Zafren, and Hermann Brugger. Fluid management in traumatic shock: a practical approach for mountain rescue. High Alt. Med. Biol. 10:71-75, 2009.-The management of severe injuries leading to traumatic shock in mountains and remote areas is a great challenge for emergency physicians and rescuers. Traumatic brain injury may further aggravate outcome. A mountain rescue mission may face severe limitations from the terrain and required rescue technique. The mission may be characterized by a prolonged prehospital care time, where urban traumatic shock protocols may not apply. Yet optimal treatment is of utmost importance. The aim of this study is to establish scientifically supported recommendations for fluid management that are feasible for the physician or paramedic attending such an emergency. A nonsystematic literature search was performed; the results and recommendations were discussed among the authors and accepted by the International Commission for Mountain Emergency Medicine (ICAR MEDCOM). Diagnostic and therapeutic strategies are discussed, as well as limitations on therapy in mountain rescue. An algorithm for fluid resuscitation, derived from the recommendations, is presented in Fig. 1. Focused on the key criterion of traumatic brain injury, different levels of blood pressure are presented as a goal of therapy, and the practical means for achieving these are given.

  11. NASA Land Cover and Land Use Change (LCLUC): an interdisciplinary research program.

    PubMed

    Justice, Chris; Gutman, Garik; Vadrevu, Krishna Prasad

    2015-01-15

    Understanding Land Cover/Land Use Change (LCLUC) in diverse regions of the world and at varied spatial scales is one of the important challenges in global change research. In this article, we provide a brief overview of the NASA LCLUC program, its focus areas, and the importance of satellite remote sensing observations in LCLUC research including future directions. The LCLUC Program was designed to be a cross-cutting theme within NASA's Earth Science program. The program aims to develop and use remote sensing technologies to improve understanding of human interactions with the environment. Since 1997, the NASA LCLUC program has supported nearly 280 research projects on diverse topics such as forest loss and carbon, urban expansion, land abandonment, wetland loss, agricultural land use change and land use change in mountain systems. The NASA LCLUC program emphasizes studies where land-use changes are rapid or where there are significant regional or global LCLUC implications. Over a period of years, the LCLUC program has contributed to large regional science programs such as Land Biosphere-Atmosphere (LBA), the Northern Eurasia Earth Science Partnership Initiative (NEESPI), and the Monsoon Area Integrated Regional Study (MAIRS). The primary emphasis of the program will remain on using remote sensing datasets for LCLUC research. The program will continue to emphasize integration of physical and social sciences to address regional to global scale issues of LCLUC for the benefit of society.

  12. Application of the micro-forward mutation assay to assess mutagenicity of airborne particulates in indoor

    SciTech Connect

    Takagi, Y.; Goto, S.; Murata, M.; Matsushita, H.; Lewtas, J.

    1988-01-01

    A validity test of the micro-forward mutation assay using Salmonella typhimurium strain TM677 was carried out using benzene-ethanol extracts from airborne particulates as test materials. Sensitivity of this assay in the presence and absence of S-9 mix was five to ten times higher than the pre-incubation method, a modified method of Ames's original method, using Salmonella typhimurium strains TA98 and TA100. This means that the virtual sensitivity of the micro-forward mutation assay is greater by ten times or more than the pre-incubation method, because two or more strains are necessary in the latter method. Repeatability of the micro-forward mutation assay was nearly same with that of the pre-incubation method. That is, the coefficient of variation of mutagenic frequency of the particulate extracts was about 10%. This forward mutation assay was applied to airborne particulates indoors, and proved to be able to measure easily the mutagenic activity of the extracts from particulates collected by 30 cu m-air sampling. Some indoor pollutants, especially ones collected in a room in which cigarette smoking was done, showed higher mutagenic activity than that of outdoor sample.

  13. What Does It Mean to be Central? A Botanical Geography of Paris 1830-1848.

    PubMed

    Hoquet, Thierry

    2016-02-01

    This paper focuses on the geography of the botanical community in Paris, under the July Monarchy (1830-1848). At that time, the Muséum d'Histoire naturelle (MHN) was at its institutional acme and, under the impulse of François Guizot, its budget was increasing dramatically. However, closer attention to manuscript sources (correspondence, travel diaries) reveals that the botanists of the time favoured other private institutions, located both on the Right and Left Banks of the Seine. The MHN was prestigious for its collections and professors but it was relatively remote from the centre of Paris, and its plant samples were sometimes difficult to access. Several other first-class private herbaria granted liberal access to botanists: those of Jacques Gay, Phillip Barker Webb, and Benjamin Delessert. Thanks to their wealth, these plant amateurs had ownership of historical herbaria consisting of species types alongside rich botanical libraries. Botanists visiting Paris from foreign countries or other provinces of France also spent some time studying less general plant collections, like those of Count Jaubert, or specialized collections, like Montagne's or Léveillé's on cryptogams. Other botanists also enjoyed renown at the time, although they published little, if anything (like Maire). Living in crammed apartments, literally in the middle of their plant samples, these botanists were key nodes in botanical networks, although they had no relation with the prestigious MHN.

  14. Midline thalamic reuniens lesions improve executive behaviors.

    PubMed

    Prasad, J A; Abela, A R; Chudasama, Y

    2017-03-14

    The role of the thalamus in complex cognitive behavior is a topic of increasing interest. Here we demonstrate that lesions of the nucleus reuniens (NRe), a midline thalamic nucleus interconnected with both hippocampal and prefrontal circuitry, lead to enhancement of executive behaviors typically associated with the prefrontal cortex. Rats were tested on four behavioral tasks: (1) the combined attention-memory (CAM) task, which simultaneously assessed attention to a visual target and memory for that target over a variable delay; (2) spatial memory using a radial arm maze, (3) discrimination and reversal learning using a touchscreen operant platform, and (4) decision-making with delayed outcomes. Following NRe lesions, the animals became more efficient in their performance, responding with shorter reaction times but also less impulsively than controls. This change, combined with a decrease in perseverative responses, led to focused attention in the CAM task and accelerated learning in the visual discrimination task. There were no observed changes in tasks involving either spatial memory or value-based decision making. These data complement ongoing efforts to understand the role of midline thalamic structures in human cognition, including the development of thalamic stimulation as a therapeutic strategy for acquired cognitive disabilities (Schiff, 2008; Mair et al., 2011), and point to the NRe as a potential target for clinical intervention.

  15. A near-infrared SETI experiment: instrument overview

    NASA Astrophysics Data System (ADS)

    Wright, Shelley A.; Werthimer, Dan; Treffers, Richard R.; Maire, Jérôme; Marcy, Geoffrey W.; Stone, Remington P. S.; Drake, Frank; Meyer, Elliot; Dorval, Patrick; Siemion, Andrew

    2014-07-01

    We are designing and constructing a new SETI (Search for Extraterrestrial Intelligence) instrument to search for direct evidence of interstellar communications via pulsed laser signals at near-infrared wavelengths. The new instrument design builds upon our past optical SETI experiences, and is the first step toward a new, more versatile and sophisticated generation of very fast optical and near-infrared pulse search devices. We present our instrumental design by giving an overview of the opto-mechanical design, detector selection and characterization, signal processing, and integration procedure. This project makes use of near-infrared (950 - 1650 nm) discrete amplification Avalanche Photodiodes (APD) that have > 1 GHz bandwidths with low noise characteristics and moderate gain (~104). We have investigated the use of single versus multiple detectors in our instrument (see Maire et al., this conference), and have optimized the system to have both high sensitivity and low false coincidence rates. Our design is optimized for use behind a 1m telescope and includes an optical camera for acquisition and guiding. A goal is to make our instrument relatively economical and easy to duplicate. We describe our observational setup and our initial search strategies for SETI targets, and for potential interesting compact astrophysical objects.

  16. Accessing Recent Trend of Land Surface Temperature from Satellite Observations

    NASA Technical Reports Server (NTRS)

    Shen, Suhung; Leptoukh, Gregory G.; Romanov, Peter

    2011-01-01

    Land surface temperature (Ts) is an important element to measure the state of terrestrial ecosystems and to study surface energy budgets. In support of the land cover/land use change-related international program MAIRS (Monsoon Asia Integrated Regional Study), we have collected global monthly Ts measured by MODIS since the beginning of the missions. The MODIS Ts time series have approximately 11 years of data from Terra since 2000 and approximately 9 years of data from Aqua since 2002, which makes possible to study the recent climate, such as trend. In this study, monthly climatology from two platforms are calculated and compared with that from AIRS. The spatial patterns of Ts trends are accessed, focusing on the Eurasia region. Furthermore, MODIS Ts trends are compared with those from AIRS and NASA's atmospheric assimilation model, MERRA (Modern Era Retrospective-analysis for Research and Applications). The preliminary results indicate that the recent 8-year Ts trend shows an oscillation-type spatial variation over Eurasia. The pattern is consistent for data from MODIS, AIRS, and MERRA, with the positive center over Eastern Europe, and the negative center over Central Siberia. The calculated climatology and anomaly of MODIS Ts will be integrated into the online visualization system, Giovanni, at NASA GES DISC for easy use by scientists and general public.

  17. Comparative analysis of transcript abundance in Pinus sylvestris after challenge with a saprotrophic, pathogenic or mutualistic fungus.

    PubMed

    Adomas, Aleksandra; Heller, Gregory; Olson, Ake; Osborne, Jason; Karlsson, Magnus; Nahalkova, Jarmila; Van Zyl, Len; Sederoff, Ron; Stenlid, Jan; Finlay, Roger; Asiegbu, Frederick O

    2008-06-01

    To investigate functional differences in the recognition and response mechanisms of conifer roots to fungi with different trophic strategies, Pinus sylvestris L. was challenged with a saprotrophic fungus Trichoderma aureoviride Rifai. The results were compared with separate studies investigating pine interactions with a pathogen, Heterobasidion annosum (Fr.) Bref. sensu stricto and an ectomycorrhizal symbiont, Laccaria bicolor Maire (Orton). Global changes in the expression of 2109 conifer genes were assayed 1, 5 and 15 days after inoculation. Gene expression data from a cDNA microarray were analyzed by the 2-interconnected mixed linear model statistical approach. The total number of genes differentially expressed compared with the uninfected control was similar after challenge with the pathogen and the ectomycorrhizal symbiont, but the number of differentially expressed genes increased over time for H. annosum, and decreased for L. bicolor. Inoculation of pine roots with T. aureoviride resulted overall in a much lower number of genes with changed transcript levels compared with inoculation with H. annosum or L. bicolor. Functional classification of the differentially expressed genes revealed that the ectomycorrhizal fungus triggered transient induction of defence-related genes. The response and induction of defence against the pathogen was delayed and the magnitude increased over time. Thus, there were specific transcriptional responses depending on whether the conifer roots were challenged with mutualistic, saprotrophic or pathogenic fungi. This suggests that pine trees are able to recognize diverse fungal species and specifically distinguish whether they are pathogenic, neutral or beneficial microbial agents.

  18. Image formation by bifocal lenses in a trilobite eye?

    PubMed

    Gál, J; Horváth, G; Clarkson, E N; Haiman, O

    2000-01-01

    In this work we report on a unique and ancient type of eye, in which the lower surface of the upper calcite lens units possessed an enigmatic central bulge making the dioptric apparatus similar to a bifocal lens. This eye belonged to the trilobite Dalmanitina socialis, which became extinct several hundred million years ago. As far as we know, image formation by bifocal lenses of this kind did/does not occur in any other ancient or modern animal visual system. We suggest that the function of these bifocal lenses may be to enable the trilobite to see simultaneously both very near (e.g. floating food particles and tiny preys) and far (e.g. sea floor, conspecifics, or approaching enemies) in the optical environment through the central and peripheral lens region, respectively. This was the only reasonable function we could find to explain the puzzling lens shape. We admit that it is not clear whether bifocality was necessary for the animal studied. We show that the misleading and accidental resemblance of an erroneous correcting lens surface (designed by René DesCartes in 1637 [DesCartes, R. (1637). Oeuvres de DesCartes. La Géometrie. Livre 2. pp. 134. J. Maire, Leyden] to the correcting interface in the compound Dalmanitina lens may be the reason why the earlier students of the Dalmanitina lens did not recognize its possible bifocality.

  19. Delmopinol-induced matrix removal facilitates photodynamic therapy and chlorhexidine methods for disinfecting mixed oral biofilms

    NASA Astrophysics Data System (ADS)

    Rogers, Stephen Christopher

    It is often observed that the slimy matrixes of various bacterial-formed biofilms can limit their disinfection. This investigation demonstrated that disinfection effectiveness by either photodynamic therapy (PDT) or chlorhexidine irrigation is significantly improved by collapse of that matrix using the non-bactericidal reagent delmopinol as part of the treatment sequence. Cyclic shear-producing conditions were used to grow 4-day, whole salivary and growth media biofilms on glow-discharge-treated polystyrene (N=46) and mini-germanium internal reflection prisms to serve in a periodontal crypt model of disinfection by either methylene-blue-mediated PDT or by chlorhexidine irrigation. Assays for bacterial viability, with and without treatments, were performed by alamarBlueRTM fluorescent methods, statistically applied (ANOVA, Tukey's HSD). Multiple Attenuated Internal Reflection Infrared (MAIR-IR) assays confirmed selective removal of the predominantly polysaccharide matrix materials by the delmopinol treatment, but not by equivalent water or chlorhexidine methods. Confocal-IR microscopy showed that the delmopinol reagent, alone, caused about one-third of each wet biofilm to be removed, while bacterial re-growth was confirmed by alamarBlueRTM assay. Chlorhexidine and PDT suppression of bacterial activity without regrowth was significantly improved with the added delmopinol treatment, and is likely to provide similarly beneficial results in the effective disinfection of diverse biofilms in many settings.

  20. Accessing Recent Trend of Land Surface Temperature from Satellite Observations

    NASA Astrophysics Data System (ADS)

    Shen, S.; Leptoukh, G. G.; Romanov, P.

    2011-12-01

    Land surface temperature (LST) is an important element to measure the state of the terrestrial ecosystems and to study the surface energy budgets. In support of the land cover/land use change related international program MAIRS (Monsoon Asia Integrated Regional Study), we have collected the global monthly LST measured by MODIS since the beginning of the missions. The MODIS LST time series have ~11 years of data from Terra since 2000 and ~9 years of data from Aqua since 2002, which makes possible to study the recent climate, such as trend and variability. In this study, monthly climatology from two satellite platforms are calculated and compared. The spatial patterns of LST trends are accessed, focusing on the Asian Monsoon region. Furthermore, the MODIS LST trends are compared with the skin temperature trend from the NASA's atmospheric assimilation model, MERRA (MODERN ERA RETROSPECTIVE-ANALYSIS FOR RESEARCH AND APPLICATIONS), which has longer data record since 1979. The calculated climatology and anomaly of MODIS LST will be integrated into the online visualization system, Giovanni, at NASA GES DISC for easy access and use by scientists and general public.

  1. Multi-modal defenses in aphids offer redundant protection and increased costs likely impeding a protective mutualism.

    PubMed

    Martinez, Adam J; Doremus, Matthew R; Kraft, Laura J; Kim, Kyungsun L; Oliver, Kerry M

    2017-04-05

    1.The pea aphid, Acyrthosiphon pisum, maintains extreme variation in resistance to its most common parasitoid wasp enemy, Aphidius ervi, which is sourced from two known mechanisms: protective bacterial symbionts, most commonly Hamiltonella defensa, or endogenously encoded defenses. We have recently found that individual aphids may employ each defense individually, occasionally both defenses together, or neither. 2.In field populations, Hamiltonella-infected aphids are found at low to moderate frequencies and while less is known about the frequency of resistant genotypes, they show up less often than susceptible genotypes in field collections. To better understand these patterns, we sought to compare the strengths and costs of both types of defense, individually and together, in order to elucidate the selective pressures that maintain multi-modal defense mechanisms or that may favor one over the other. 3.We experimentally infected five aphid genotypes (two lowly and three highly resistant), each with two symbiont strains, Hamiltonella-APSE8 (moderate protection) and Hamiltonella-APSE3 (high protection). This resulted in three sublines per genotype: uninfected, +APSE8, and +APSE3. Each of the fifteen total sublines was first subjected to a parasitism assay to determine its resistance phenotype and in a second experiment a subset were chosen to compare fitness (fecundity and survivorship) in presence and absence of parasitism. 4.In susceptible aphid genotypes, parasitized sublines infected with Hamiltonella generally showed increased protection with direct fitness benefits, but clear infection costs to fitness in the absence of parasitism. In resistant genotypes, Hamiltonella infection rarely conferred additional protection, often further reduced fecundity and survivorship when enemy challenged, and resulted in constitutive fitness costs in the absence of parasitism. We also identified strong aphid-genotype X symbiont-strain interactions, such that the best defensive

  2. Radiological investigation of phosphate fertilizers: Leaching studies.

    PubMed

    Hegedűs, Miklós; Tóth-Bodrogi, Edit; Németh, Szabolcs; Somlai, János; Kovács, Tibor

    2016-10-19

    The raw materials of the phosphate fertilizer industry are the various apatite minerals. Some of these have high levels of natural radionuclides, and thus phosphate fertilizers contain significant amounts of U-238, K-40 and Ra-226. These can leach out of the fertilizers used in large quantities for resupplying essential nutrients in the soil and can then enter the food chain through plants, thereby increasing the internal dose of the affected population. In the current study, the radiological risk of eight commercially available phosphate fertilizers (superphosphate, NPK, PK) and their leaching behaviours were investigated using different techniques (gamma and alpha spectrometry), and the dose contributions of using these fertilizers were estimated. To characterize the leaching behaviour, two leaching procedures were applied and compared -the MSZ 21470-50 (Hungarian standard) and the Tessier five-step sequential extraction method. Based on the evaluation of the gamma-spectra, it is found that the level of Th-232 in the samples was low (max.7 ± 6 Bq kg(-1)), the average Ra-226 activity concentration was 309 ± 39 Bq kg(-1) (min. 10 ± 8 Bq kg(-1), max. 570 ± 46 Bq kg(-1)), while the K-40 concentrations (average 3139 ± 188 Bq kg(-1), min. 51 ± 36 Bq kg(-1)) could be as high as 7057 ± 427 Bq kg(-1). The high K-40 can be explained by reference to the composition of the investigated fertilizers (NPK, PK). U concentrations were between 15 and 361 Bq kg(-1), with the average of 254 Bq kg(-1), measured using alpha spectrometry. The good correlation between P2O5 content and radioactivity reported previously is not found in our data. The leaching studies reveal that the mobility of the fertilizer's uranium content is greatly influenced by the parameters of the leaching methods. The availability of U to water ranged between 3 and 28 m/m%, while the Lakanen-Erviö solution mobilized between 10 and 100% of the U content.

  3. Topsoil investigation on two different urban areas in West Hungary

    NASA Astrophysics Data System (ADS)

    Horváth, Adrienn; Bidló, András

    2015-04-01

    Heavy metal contents of urban soils in two different urban areas have been investigated in Sopron town (169.01 km2) and in Szombathely town 97.50 km2) in Hungary. In a standard network 208 samples have been collected Sopron from 0 to 10 and from 10 to 20 cm depth. 164 samples have been taken on 88 points in the area of Szombathely. We analysed all of the soil samples with ICP equipment applying Lakanen-Erviö method (Ammonium Acetate - EDTA (pH 4.65)) and we focused on Co, Cu, Ni, Pb and Zn during the evaluation. The soils of suburb are determined largely by the bedrock, but in the downtown the soil pH was alkaline in soils of Sopron. Therefore, the toxic elements are still accumulated in the topsoil. The lead content was very high (suggested pollution limit >25 mg Pb/kg) in both layers on the whole area of the town. Urban soils with high copper content (among 611 mg and 1221 mg Cu/kg) have been collected from garden and viticulture areas. According to our measurements we found the highest average values in the soils of parks. The pH of urban topsoils of Szombathely was mostly neutral and it was lower in soil of agricultural areas on the suburb, where the artificial fertiliser is still used. The Pb content was high (more than 25 mg Pb/kg) in case of 13 samples next to traffic roads of the town. The Co, Cu and Ni results were below the suggested Hungarian background limits. The Zn values were above the suggested Hungarian pollution (20 mg Zn/kg) and interventional limits (>40 mg Zn/kg) in most cases. According to the results we found the highest average values of heavy metals in the soil of traffic areas or next to the Gyöngyös creek, which could be originated from traffic contamination, binding in the soil of urban green spaces, thus possibly affects human health. The research is supported by the "Agroclimate-2" (VKSZ_12-1-2013-0034) joint EU-national research project. Keywords: anthropogenic effects, heavy metal content, lead pollution, polluted urban soils

  4. Updating soil CO2 emission experiments to assess climate change effects and extracellular soil respiration

    NASA Astrophysics Data System (ADS)

    Vidal Vazquez, Eva; Paz Ferreiro, Jorge

    2014-05-01

    Experimental work is an essential component in training future soil scientists. Soil CO2 emission is a key issue because of the potential impacts of this process on the greenhouse effect. The amount of organic carbon stored in soils worldwide is about 1600 gigatons (Gt) compared to 750 Gt in the atmosphere mostly in the form of CO2. Thus, if soil respiration increased slightly so that just 10% of the soil carbon pool was converted to CO2, atmospheric CO2 concentrations in the atmosphere could increase by one-fifth. General circulation model predictions indicate atmosphere warming between 2 and 5°C (IPCC 2007) and precipitation changes ranging from about -15 to +30%. Traditionally, release of CO2 was thought to occur only in an intracellular environment; however, recently CO2 emissions have been in irradiated soil, in the absence of microorganisms (Maire et al., 2013). Moreover, soil plays a role in the stabilization of respiration enzymes promoting CO2 release after microorganism death. Here, we propose to improve CO2 emission experiments commonly used in soil biology to investigate: 1) effects of climatic factors on soil CO2 emissions, and 2) rates of extracellular respiration in soils and how these rates are affected by environmental factors. Experiment designed to assess the effect of climate change can be conducted either in field conditions under different ecosystems (forest, grassland, cropland) or in a greenhouse using simple soil chambers. The interactions of climate change in CO2 emissions are investigated using climate-manipulation experiment that can be adapted to field or greenhouse conditions (e.g. Mc Daniel et al., 2013). The experimental design includes a control plot (without soil temperature and rain manipulation) a warming treatment as well as wetting and/or drying treatments. Plots are warmed to the target temperature by procedures such as infrared heaters (field) or radiant cable (greenhouse). To analyze extracellular respiration, rates of CO2

  5. Online Time Series Analysis of Land Products over Asia Monsoon Region via Giovanni

    NASA Technical Reports Server (NTRS)

    Shen, Suhung; Leptoukh, Gregory G.; Gerasimov, Irina

    2011-01-01

    Time series analysis is critical to the study of land cover/land use changes and climate. Time series studies at local-to-regional scales require higher spatial resolution, such as 1km or less, data. MODIS land products of 250m to 1km resolution enable such studies. However, such MODIS land data files are distributed in 10ox10o tiles, due to large data volumes. Conducting a time series study requires downloading all tiles that include the study area for the time period of interest, and mosaicking the tiles spatially. This can be an extremely time-consuming process. In support of the Monsoon Asia Integrated Regional Study (MAIRS) program, NASA GES DISC (Goddard Earth Sciences Data and Information Services Center) has processed MODIS land products at 1 km resolution over the Asia monsoon region (0o-60oN, 60o-150oE) with a common data structure and format. The processed data have been integrated into the Giovanni system (Goddard Interactive Online Visualization ANd aNalysis Infrastructure) that enables users to explore, analyze, and download data over an area and time period of interest easily. Currently, the following regional MODIS land products are available in Giovanni: 8-day 1km land surface temperature and active fire, monthly 1km vegetation index, and yearly 0.05o, 500m land cover types. More data will be added in the near future. By combining atmospheric and oceanic data products in the Giovanni system, it is possible to do further analyses of environmental and climate changes associated with the land, ocean, and atmosphere. This presentation demonstrates exploring land products in the Giovanni system with sample case scenarios.

  6. Aqueous benzene-diols react with an organic triplet excited state and hydroxyl radical to form secondary organic aerosol.

    PubMed

    Smith, Jeremy D; Kinney, Haley; Anastasio, Cort

    2015-04-21

    Chemical processing in atmospheric aqueous phases, such as cloud and fog drops, can play a significant role in the production and evolution of secondary organic aerosol (SOA). In this work we examine aqueous SOA production via the oxidation of benzene-diols (dihydroxy-benzenes) by the triplet excited state of 3,4-dimethoxybenzaldehyde, (3)DMB*, and by hydroxyl radical, ˙OH. Reactions of the three benzene-diols (catechol (CAT), resorcinol (RES) and hydroquinone (HQ)) with (3)DMB* or ˙OH proceed rapidly, with rate constants near diffusion-controlled values. The two oxidants exhibit different behaviors with pH, with rate constants for (3)DMB* increasing as pH decreases from pH 5 to 2, while rate constants with ˙OH decrease in more acidic solutions. Mass yields of SOA were near 100% for all three benzene-diols with both oxidants. We also examined the reactivity of atmospherically relevant mixtures of phenols and benzene-diols in the presence of (3)DMB*. We find that the kinetics of phenol and benzene-diol loss, and the production of SOA mass, in mixtures are generally consistent with rate constants determined in experiments containing a single phenol or benzene-diol. Combining our aqueous kinetic and SOA mass yield data with previously published gas-phase data, we estimate a total SOA production rate from benzene-diol oxidation in a foggy area with significant wood combustion to be nearly 0.6 μg mair(-3) h(-1), with approximately half from the aqueous oxidation of resorcinol and hydroquinone, and half from the gas-phase oxidation of catechol.

  7. Deformation and Fluid Flow in the Etendeka Plateau, NW Namibia

    NASA Astrophysics Data System (ADS)

    Salomon, Eric; Koehn, Daniel; Passchier, Cees; Davis, Jennifer; Salvona, Aron; Chung, Peter

    2014-05-01

    We studied deformation bands in sandstone and breccia veins in overlying basalts of the Etendeka Plateau, NW Namibia, regarding their development and history of fluid flow within. The studied deformation bands can be divided into disaggregation bands and cataclastic bands. The former appear to develop in unsorted sandstone, whereas the latter form in well sorted sandstone. We estimated the porosity of the bands and host rock in thin sections using a simple image analysis software (ImageJ). Results show, that no or only a minor decrease in porosity occur in disaggregation bands, while the porosity in cataclastic bands is decreased by up to 82 % with respect to the host rock. These observations are in agreement with results of existing studies (e.g. Fossen et al., 2007). Hence the cataclastic bands form a seal to fluid flow in the host rock, yet it is observed in outcrops that deformation bands can develop into open fractures which in turn increase the permeability of the rock. Breccia veins in the overlying basalts show intense fracturing where the basalt is locally fractured into elongated chips. Mineral precipitation in these breccia veins indicates a hydrothermal origin of the fluids since the precipitates consist of extremely fine-grained quartz aggregates. Secondary mineralization with large crystals indicates that a long-lived fluid circulation through tubular networks was active at a later stage, which eventually sealed the veins completely. We propose that the Etendeka basalts on top of the sandstone formation produced a localized deformation along deformation bands and heated up fluid below the lavas. At a later stage fluid pressures were either high enough to break through the basalt or fracturing due to ongoing extension produced fluid pathways. References Fossen, H., Schultz, R., Shipton, Z. and Mair, K. (2007). Deformation bands in sandstone: a review. J. Geol. Soc., 164, 755-769.

  8. AMPK controls exercise endurance, mitochondrial oxidative capacity, and skeletal muscle integrity.

    PubMed

    Lantier, Louise; Fentz, Joachim; Mounier, Rémi; Leclerc, Jocelyne; Treebak, Jonas T; Pehmøller, Christian; Sanz, Nieves; Sakakibara, Iori; Saint-Amand, Emmanuelle; Rimbaud, Stéphanie; Maire, Pascal; Marette, André; Ventura-Clapier, Renée; Ferry, Arnaud; Wojtaszewski, Jørgen F P; Foretz, Marc; Viollet, Benoit

    2014-07-01

    AMP-activated protein kinase (AMPK) is a sensor of cellular energy status that plays a central role in skeletal muscle metabolism. We used skeletal muscle-specific AMPKα1α2 double-knockout (mdKO) mice to provide direct genetic evidence of the physiological importance of AMPK in regulating muscle exercise capacity, mitochondrial function, and contraction-stimulated glucose uptake. Exercise performance was significantly reduced in the mdKO mice, with a reduction in maximal force production and fatigue resistance. An increase in the proportion of myofibers with centralized nuclei was noted, as well as an elevated expression of interleukin 6 (IL-6) mRNA, possibly consistent with mild skeletal muscle injury. Notably, we found that AMPKα1 and AMPKα2 isoforms are dispensable for contraction-induced skeletal muscle glucose transport, except for male soleus muscle. However, the lack of skeletal muscle AMPK diminished maximal ADP-stimulated mitochondrial respiration, showing an impairment at complex I. This effect was not accompanied by changes in mitochondrial number, indicating that AMPK regulates muscle metabolic adaptation through the regulation of muscle mitochondrial oxidative capacity and mitochondrial substrate utilization but not baseline mitochondrial muscle content. Together, these results demonstrate that skeletal muscle AMPK has an unexpected role in the regulation of mitochondrial oxidative phosphorylation that contributes to the energy demands of the exercising muscle.-Lantier, L., Fentz, J., Mounier, R., Leclerc, J., Treebak, J. T., Pehmøller, C., Sanz, N., Sakakibara, I., Saint-Amand, E., Rimbaud, S., Maire, P., Marette, A., Ventura-Clapier, R., Ferry, A., Wojtaszewski, J. F. P., Foretz, M., Viollet, B. AMPK controls exercise endurance, mitochondrial oxidative capacity, and skeletal muscle integrity.

  9. [Medicine and humanism: insights of the Nürnberg city physician Theodericus Ulsenius regarding Morbus Gallicus].

    PubMed

    Santing, C G

    1995-01-01

    The Nuremberg physician and humanist Theodericus Ulsenius (c. 1460-1508) was the author of two works on the so-called Morbus Gallicus. In 1496 he published a Vaticinium in epidemicam scabiem, and he also wrote fifty aphorisms, entitled Cura mali francici. In this article I will characterize Ulsenius' ideas and compare these to the measures the Nuremberg town government took to diminish the dangerous effects of the epidemic. In the function of official town physician, Ulsenius was one of the chief advisers and executives of the Nuremberg health policy. As the 'Ratsverlässe' (records of the town-council meetings) give detailed information, the reactions of senate and physicians can be followed from day to day. The Vaticinium a poem of 100 hexameters was printed at the office of Hans Mair and presented as a pamphlet with a woodcut from the workshop of Albrecht Dürer. The verses refer to a dream of the poet, in which the God Apollo addresses him and talks about the terrible disease. The origin and symptoms of the illness are discussed extensively, in accordance with the prevailing medico-astrological conceptions. Nevertheless, the poem ist not a medical piece of work, but a literary-styled and humanistically appropriate description of the recent epidemic, meant for fellow members of the German respublica litteraria. Like most of Ulsenius' writings, the Cura mali francici only survived as a copy made by his colleague Hartmann Schedel. It seems that the author had different types of audience in mind. The aphorisms refer to the Aphorisms of his great example, the famous Ancient medical doctor Hippocrates of Kos. The addresses of the Cura are obviously medical professionals: the physician in the towns harassed by the Morbus Gallicus and especially the medical professors who hat to lecture on the new ailment.

  10. Sonification for geoscience: Listening to faults from the inside

    NASA Astrophysics Data System (ADS)

    Barrett, Natasha; Mair, Karen

    2014-05-01

    Here we investigate the use of sonification for geoscience by sonifying the data generated in computer models of earthquake processes. Using mainly parameter mapping sonification, we explore data from our recent 3D DEM (discrete element method) models where granular debris is sheared between rough walls to simulate an evolving fault (e.g. Mair and Abe, 2011). To best appreciate the inherently 3D nature of the crushing and sliding events (continuously tracked in our models) that occur as faults slip, we use Ambisonics (a sound field recreation technology). This allows the position of individual events to be preserved generating a virtual 3D soundscape so we can explore faults from the inside. The addition of 3D audio to the sonification tool palate further allows us to more accurately connect to spatial data in a novel and engaging manner. During sonification, events such as grain scale fracturing, grain motions and interactions are mapped to specific sounds whose pitch, timbre, and volume reflect properties such as the depth, character, and size of the individual events. Our interactive and real-time approaches allow the listener to actively explore the data in time and space, listening to evolving processes by navigating through the spatial data via a 3D mouse controller. The soundscape can be heard either through an array of speakers or using a pair of headphones. Emergent phenomena in the models generate clear sound patterns that are easily spotted. Also, because our ears are excellent signal-to-noise filters, events are recognizable above the background noise. Although these features may be detectable visually, using a different sense (and part of the brain) gives a fresh perspective and facilitates a rapid appreciation of 'signals' through audio awareness, rather than specific scientific training. For this reason we anticipate significant potential for the future use of sonification in the presentation, interpretation and communication of geoscience datasets

  11. Crotalaria (Crotalaria juncea L.) Heavy Metal Uptake in Eastern Hungary

    NASA Astrophysics Data System (ADS)

    László Phd, M., ,, Dr.

    2009-04-01

    Summary: Soil condition, plant production and ecological protection are most important parts of the sustainable agricultural activity on all over the world nowadays. Soils, their fertility, their content of different macro-, mezo-, micro-, trace elements have almost always dictated the spread of agricultural farmlands, including the plant production-, yield harvest levels and yield element contents possible. The success of agriculturists in the 20th and 21th century, particularly in the Europe has relied on inproved soil fertility managements, appropriate crop production and environmental protection. We can test and improve the situations by using different plant species (Crotalaria juncea L.) x macro nutrients (nitrogen) x chelating agents (Desferal as deferoxamine-mesilate: C25H48N6O8-CH4O3S) methods. Crotalaria has a very potential and important role in soil fertility as a green manure crop in the design of plant rotation to field plant production, in the animal foraging as a fodder-crop with a high protein content (30%) and in the pytoremediation possibilities. Field experiment was carried out on a calcareous chernozem meadow soil (Kunság-region of Hungary, Kunmadaras) in partly of crotalaria experiment series (5 years) in 2001. The agrochemical parameters of the ploughed layer of the region soils were as follows: humus 2.5-3.0%, pH (H2O) 7.7, pH (KCl) 7.0, LE (Lakanen & Erviö 1971 [3])-P2O5 183-218 mg kg-1, LE-K2O 82-115 mg kg-1, LE-Ca 1.3%, LE-Mg 56-60 mg kg-1, LE-Mn 45 mg kg-1 according to soil analysis. Nitrogen (N) x Desferal ("D"-Novartis Pharma AG Basie [7], Switzerland, Suiza 500 mg) x Genotype ("G"-India-University of Agricultural Sciences, Bangalore) x Time (T) experiment involved The N levels were 0, 100, 200 and 300 kg ha-1 year-1, and Desferal 0 and 20 kg ha-1 year-1. The plot size had an area of 4x2=8 m2. Experimental datas were estimated by MANOVA of SPSS. The main results can be summarised as follows: a., At harvest, total air dry phytomass

  12. Unusual isotopic composition of C-CO2 from sterilized soil microcosms: a new way to separate intracellular from extracellular respiratory metabolisms.

    NASA Astrophysics Data System (ADS)

    Kéraval, Benoit; Alvarez, Gaël; Lehours, Anne Catherine; Amblard, Christian; Fontaine, Sebastien

    2015-04-01

    The mineralization of organic C requires two main steps. First, microorganisms secrete exoenzymes in soil in order to depolymerize plant and microbial cell walls and release soluble substrates for microbial assimilation. The second step of mineralization, during which C is released as CO2, implies the absorption and utilization of solubilized substrates by microbial cells with the aim to produce energy (ATP). In cells, soluble substrates are carried out by a cascade of respiratory enzymes, along which protons and electrons are transferred from a substrate to oxygen. Given the complexity of this oxidative metabolism and the typical fragility of respiratory enzymes, it is traditionally considered that respiration (second step of C mineralization process) is strictly an intracellular metabolism process. The recurrent observations of substantial CO2 emissions in soil microcosms where microbial cells have been reduced to extremely low levels challenges this paradigm. In a recent study where some respiratory enzymes have shown to function in an extracellular context in soils, Maire et al. (2013) suggested that an extracellular oxidative metabolism (EXOMET) substantially contributes to CO2 emission from soils. This idea is supported by the recent publication of Blankinship et al., 2014 who showed the presence of active enzymes involved in the Krebs cycle on soil particles. Many controversies subsist in the scientific community due to the presence of non-proliferating but morphologically intact cells after irradiation that could substantially contribute to those soil CO2 emissions. To test whether a purely extracellular oxidative metabolism contribute to soil CO2 emissions, we combined high doses of gamma irradiations to different time of soil autoclaving. The presence of active and non-active cells in soil was checked by DNA and RNA extraction and by electronic microscopy. None active cells (RNA-containing cells) were detectable after irradiation, but some morphological

  13. Assessment of the thermal and dynamic reaction scenarios of different permafrost typologies in the European Alps: A PermaNET initiative

    NASA Astrophysics Data System (ADS)

    Kellerer-Pirklbauer, A.

    2009-04-01

    (Murtèl/Corvatsch, Schilthorn, Matterhorn), in Germany (Zugspitze) and in France (Haute-Savoie, Rhône-Alpes, Mont Blanc massif, Combe du Laurichard, Deux-Alpes ski resort, Orelle-Plan Bouchet ski resort, Bérard valley). The study sites will be presented and some preliminary results will be discussed on the poster. (* E. Cremonese, M. Dall'Amico, P. Deline, A. Galuppo, S. Gruber, J.-M. Krysiecki, G.K. Lieb, V. Mair, M. Maukisch, U. Morra di Cella, P. Pogliotti, A. von Poschinger, L. Ravanel, C. Riedl, P. Schoeneich, R. Seppi, M. Staudinger, G. Zampedri)

  14. EDITORIAL: Slow light Slow light

    NASA Astrophysics Data System (ADS)

    Boyd, Robert; Hess, Ortwin; Denz, Cornelia; Paspalakis, Emmanuel

    2010-10-01

    storage, optical memories, quantum information devices, and optical communication systems in which the use of slow light will allow all-optical processing with less wasted heat. To implement these applications, devices such as buffers, memories, interferometers and switches that utilize slow light need to be developed. Future challenges include the need for improved coupling of light into slow light modes, overcoming propagation losses, and mitigating the influence of large dispersion of the group velocity. The collection of papers in this special issue of Journal of Optics features a broad spectrum of articles that highlight actual developments in many of the material types and schemes described above. It represents therefore an excellent up to date snapshot of the current state of the field of slow light research. References [1] Lorentz H A 1880 Uber die Beziehung zwischen der Fortpflanzung des Lichtes und der Körperdichte Wiedemann Ann. 9 641-64 [2] McCall S L and Hahn E L 1967 Self-induced transparency by pulsed coherent light Phys. Rev. Lett. 18 908-11 [3] Vestergaard Hau L, Harris S E, Dutton Z and Behroozi C H 1999 Nature 397 594 [4] Philips D F, Fleischhauer A, Mair A, Walsworth R L and Lukin M D 2001 Storage of light in atomic vapor Phys. Rev. Lett. 86 783-6

  15. Rising CO2 widens the transpiration-photosynthesis optimality space

    NASA Astrophysics Data System (ADS)

    de Boer, Hugo J.; Eppinga, Maarten B.; Dekker, Stefan C.

    2016-04-01

    ). Measurements of gs and V cmax were obtained with a portable photosynthesis system. Our empirical results support the prediction that the V cmax:gs-ratio increases with higher CO2 in both Solanum genotypes. The 'dry' genotype revealed a significantly higher Huber value and lower V cmax than the 'wet' genotype at each CO2 growth level. Moreover, we found that the down-regulation of V cmax under higher CO2 was stronger in the 'dry' genotype than in the 'wet' genotype, whereas no change in the Huber value was observed between CO2 levels. Consistent with the theoretical trade-off between the resulting costs of transpiration and photosynthesis, we found that the CO2-induced increase in the V cmax:gs-ratio was stronger in the 'wet' genotype than in the 'dry' genotype. Given the divergence of V cmax:gs relationships observed, we conclude that rising atmospheric CO2 may widen the V cmax - gs optimality space available for plants to achieve an optimal trade-off between photosynthesis and transpiration. References Prentice, I. C., Dong, N., Gleason, S. M., Maire, V. and Wright, I. J.: Balancing the costs of carbon gain and water transport: testing a new theoretical framework for plant functional ecology, Ecol. Lett., 17(1), 82-91, 2014.

  16. Ultra-Pure Water and Extremophilic Bacteria interactions with Germanium Surfaces

    NASA Astrophysics Data System (ADS)

    Sah, Vasu R.

    Supported by a consortium of semiconductor industry sponsors, an international "TIE" project among 5 National Science Foundation (NSF) Industry/university Cooperative Research Centers discovered that a particular extremophilic microbe, Pseudomonas syzygii, persists in the UltraPure Water (UPW) supplies of chip fabrication facilities (FABs) and can bio-corrode germanium wafers to produce microbe-encased optically transparent crystals. Considered as potentially functional "biochips", this investigation explored mechanisms for the efficient and deliberate production of such microbe-germania adducts as a step toward later testing of their properties as sensors or switches in bioelectronic or biophotonic circuits. Recirculating UPW (Ultra-Pure Water) and other purified water, laminar-flow loops were developed across 50X20x1mm germanium (Ge) prisms, followed by subsequent examination of the prism surfaces using Multiple Attenuated Internal Reflection InfraRed (MAIR-IR) spectroscopy, Contact Potential measurements, Differential Interference Contrast Light Microscopy (DICLM), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDS), and Electron Spectroscopy for Chemical Analysis (ESCA; XPS). P. syzygii cultures originally obtained from a working FAB at University of Arizona were successfully grown on R2A minimal nutrient media. They were found to be identical to the microbes in stored UPW from the same facility, such microbes routinely capable of nucleation and entrapment within GeO2 crystals on the Ge flow surfaces. Optimum flow rates and exposure times were 1 ml/minute (3.2 s-1 shear rate) for 4 days at room temperature, producing densest crystal arrays at the prism central zones 2-3 cm from the flow inlets. Other flow rates and exposure times have higher shear rate which induces a different nucleation mechanism and saturation of crystal formation. Nucleation events began with square and circular oxide deposits surrounding active attached bacteria

  17. Crush-2: Communicating research through a science-art collaboration

    NASA Astrophysics Data System (ADS)

    Mair, K.; Barrett, N.; Schubnel, A. J.; Abe, S.

    2011-12-01

    Historically, the Earth's environment and dynamics have influenced and inspired the arts. Art in turn is a powerful vehicle for expression of the natural world. It lends itself to public presentation in many forms and appeals to a diverse audience. Science-art collaborations provide a unique opportunity to connect with the public by taking science out of the classroom and into museums, galleries and public spaces. Here we investigate the use of contemporary digital sound-art in communicating geoscience research to the general public through the installation Crush-2. Crush-2, is an interactive sound-art installation exploring the microscopic forces released during the crushing of rock. Such processes have a strong influence on the sliding behaviour and hence earthquake potential of active faults. This work is a collaboration between sound artist and composer Natasha Barrett (Oslo) and geoscientists Karen Mair (University of Oslo), Alexandre Schubnel (Ecole Normale Superieure, Paris) and Steffen Abe (RWTH Aachen). Using a sonification technique, Barrett has assigned sound recorded from rocks, of different pitches, timbres and durations, to individual fracturing events produced in our 3D fault fragmentation models and laboratory rock breaking experiments. In addition, ultrasonic acoustic emissions recorded directly in the laboratory are made audible for our hearing and feature in the work. The installation space comprises a loudspeaker array and sensor enabled helmet with wireless headphones. By wearing the helmet, moving and listening, the audience explores an artistic interpretation of the scientific data in physical space. On entering the space, one is immediately immersed in a 3D cacophony of sound. Sustained or intermittent pings, burrs, plops and tingles jostle for position in our heads whilst high pitched delicate cascades juxtapose with deep thunder like rumbles. Depending on the user's precise path through the soundscape, the experience changes accordingly

  18. The Joint Aerosol-Monsoon Experiment (JAMEX): A Core Element for the Asian Monsoon Year (2008-2009)

    NASA Technical Reports Server (NTRS)

    Lau, William K.M.

    2007-01-01

    Tropospheric Aerosol: an International Regional Experiment (East-AIRE), and Radiation Aerosol Joint Observations - Monsoon Experiments over the Gangetic Himalayas Area (Rajo-Megha: dust cloud in Sanskrit) from the US, and Monsoon Asia Integrated Regional Study (MAIR) under the Earth Systems I Science Partnership (ESSP) and WCRP. For JAMEX to succeed, it is crucial for an international body, such as CEOP or an organization under WCRP to provide the science oversight, data policy and stewardship, and to promote collaboration and partnership among national programs. It makes eminent sense for WCRP to expand the concept and the prototype proposed by JAMEX to include all monsoon countries to expand AMY08-09 into an International Monsoon Era (2008- 2013). Such an establishment followed by establishment of an international body for science oversight, and data stewardship will go a long way in promoting coordination and connection among various existing monsoon research programs within WCRP, and with burgeoning national programs on monsoon and aerosol research.

  19. The Joint Aerosol-Monsoon Experiment (JAMEX): A Core Element for the Asian Monsoon Year (2008-2009)

    NASA Technical Reports Server (NTRS)

    Lau, WIlliam K. M.

    2007-01-01

    Tropospheric Aerosol: an International Regional Experiment (East-AIRE), and Radiation Aerosol Joint Observations - Monsoon Experiments over the Gangetic Himalayas Area (Rajo-Megha: dust cloud in Sanskrit) from the US, and Monsoon Asia Integrated Regional Study (MAIR) under the Earth Systems Science Partnership (ESSP) and WCRP. For JAMEX to succeed, it is crucial for an international body, such as CEOP or an organization under WCRP to provide the science oversight, data policy and stewardship, and to promote collaboration and partnership among national programs. It makes eminent sense for WCRP to expand the concept and the prototype proposed by JAMEX to include all monsoon countries to expand AMY08-09 into an International Monsoon Era (2008- 2013). Such an establishment followed by establishment of an international body for science oversight, and data stewardship will go a long way in promoting coordination and connection among various existing monsoon research programs within WCRP, and with burgeoning national programs on monsoon and aerosol research.

  20. A new rock glacier inventory of the Lombardy, Central Alps, Italy

    NASA Astrophysics Data System (ADS)

    Scotti, R.; Brardinoni, F.; Alberti, S.; Frattini, P.; Crosta, G. B.

    2012-04-01

    lower limit, sets respectively at 2590 m a.s.l. and 2200 m a.s.l. for intact and relict types. The majority of the inventoried landforms sits within the 2000-2500 m (53 %) and 2500-3000 m (39%) elevations belts. In order to explore potential lithologic controls on rock glacier abundance, we calculate surface ratios across major lithological categories. This attribute for a given lithology is the ratio between the combined surface of the inventoried landforms and the relevant terrain surface over the 1460 m a.s.l. (i.e. minimum elevation of the lowest relict rock glacier). Higher rock glacier densities are found in intrusive (0.032) and metamorphic (0.031) rocks, followed by extrusive (0.017) and sedimentary ones (0.012). This inventory represents a necessary preliminary step for modelling the spatial distribution of permafrost at the regional scale. We believe the inventory integrates well with prior and ongoing research on the cryosphere of the Alps. In particular, our research effort fills a strategic geographic gap in the context of the PermaNET initiative. - Cremonese, E., Gruber, S., Phillips, M., Pogliotti, P., Boeckli, L., Noetzli, J., Suter, C., Bodin, X., Crepaz, A., Kellerer-Pirklbauer, A., Lang, K., Letey, S., Mair, V., Morra di Cella, U., Ravanel, L., Scapozza, C., Seppi, R., and Zischg, A. 2011, Brief Communication: "An inventory of permafrost evidence for the European Alps", The Cryosphere Discuss., 5, 1201-1218. - Scapozza, C., Mari, S. 2010, Catasto, caratteristiche e dinamica dei rock glaciers delle Alpi Ticinesi. Bollettino della società ticinese di Scienze Naturali - 98, 2010 pp 15-29.

  1. Influence of elastomeric seal plate surface chemistry on interface integrity in biofouling-prone systems: Evaluation of a hydrophobic "easy-release" silicone-epoxy coating for maintaining water seal integrity of a sliding neoprene/steel interface

    NASA Astrophysics Data System (ADS)

    Andolina, Vincent L.

    Attenuated Internal Reflection (MAIR-IR) and Microscopic Infrared Spectroscopy for organic surface compositional details, light microscopy for wear area quantification, and profilometry for surface roughness estimation and wear depth quantification. Pin-on-disc dynamic Coefficient of Friction (CoF) measurements provided data relevant to forecasts of seal integrity in dry, wet and biofouling-influenced sliding contact. Actual wear of neoprene seal material against uncoated and coated steel surfaces, wet and dry, was monitored after both rotary and linear cyclic wear testing, demonstrating significant reductions in elastomer wear areas and depths (and resultant volumes) when the coating was present. Coating the steel eliminated a 270% increase in neoprene surface area wear and an 11-fold increase in seal abrasive volume loss associated with underwater rusting in rotary experiments. Linear testing results confirm coating efficacy by reducing wear area in both loading regimes by about half. No coating delamination was observed, apparently due to a differential distribution of silicone and epoxy ingredients at the air-exposed vs. steel-bonded interfaces demonstrated by IR and EDS methods. Frictional testing revealed higher Coefficients of Friction (CoF) associated with the low-speed sliding of Neoprene over coated rather than uncoated steel surfaces in a wet environment, indicating better potential seal adhesion between the hydrophobic elastomer and coating than between the elastomer and intrinsically hydrophilic uncoated steel. When zebra mussel biofouling debris was present in the articulating joints, CoF was reduced as a result of a water channel path produced between the articulating surfaces by the retained biological matter. Easier release of the biofouling from the low-CST coated surfaces restored the seal integrity more rapidly with further water rinsing. Rapid sliding diminished these biofouling-related differences, but revealed a significant advantage in reducing the Co

  2. Trace element mobility at the slab-mantle interface: constraints from "hybrid

    NASA Astrophysics Data System (ADS)

    Marocchi, M.; Tropper, P.; Mair, V.; Bargossi, G. M.; Hermann, J.

    2009-04-01

    the phlogopite-rich zone suggests that the trace element signature of subduction zone fluids may be fractionated in this zone. The progressive depletion in some trace elements (LREE and LILE) and enrichment in Li from the gneiss towards the peridotite suggests a strong influence of bulk composition on the trace element budget of hydrous minerals. Since these metasomatic zones can be representative of the processes occurring at the slab-mantle interface, we can infer that metasomatic reactions between slab-derived fluids and ultramafic mantle wedge will follow a specific series of reactions and create mineral zones similar to those observed in this study. Despite the mobility of many elements, in the trace element profiles for amphibole and phlogopite across the different zones, we observe a rapid decrease even of the "fluid mobile" element contents within the reaction zone. With the exception of Li, we assist to an abrupt decrease of most of trace element concentrations going towards the peridotite side contact. Thus, according to the present study, it is not likely that the "crustal trace element signature" (i.e. LILE and LREE-enriched) could be able to travel far into the mantle. Our results further favour the evidence that the primary composition of subduction zone fluids reaching the source region of arc magmas is substantially modified by metasomatic reactions occurring in the mantle wedge. Furthermore, we underline that metasomatic rocks such as those observed at Mt. Hochwart are potentially able to transport H2O and other trace elements to greater depths in subduction zones. References: Marocchi M, Hermann J, Morten L (2007)-Lithos 99: 85-104. Marocchi M, Mair V, Tropper P, Bargossi GM (2009)-Mineral Petrol, in press Miller DP, Marschall RH, Schumacher JC (2009)- Lithos 107: 53-67. Scambelluri M, Hermann J, Morten L, Rampone E (2006)- Contrib Mineral Petrol 151:372-394. Spandler CJ, Hermann J, Faure K, Mavrogenes JA, Arculus RJ (2008)- Contrib Mineral Petrol

  3. Dual-sensor mapping of mass balance on Russia's northernmost ice caps

    NASA Astrophysics Data System (ADS)

    Nikolskiy, D.; Malinnikov, V.; Sharov, A.; Ukolova, M.

    2012-04-01

    th century. Hence only net balance values were determined for those ice caps. Other ice caps belong to the category of slow-moving or passive glaciers with simpler estimation of mass balance characteristics. Glacier elevation changes on several study glaciers were repeatedly determined with ICESat GLA06 data releases 28 and 29, and statistically compared. The root mean square difference between test determinations was given as less than 1 m rms and the lidar oversaturation effect was neglected in further work. Modern outlines of maritime glacier faces were corrected with the high-resolution optical quicklook imagery obtained from WorldView and QuickBird satellites. The research revealed the reduction of glacier area and general lowering of the glacier surface on most ice caps. Several new islets were discovered due to the glacial retreat in northern parts of Eva-Liv, Schmidt and Komsomolets islands. The cumulative mass budget in the study region remained negative while individual rates of volume change varied from -0.09 km3/a to +0.04 km3/a. Positive values of average mass balance with the maximum accumulation signal of approx. 0.9 m/a were determined on Ushakova, Schmidt and Henrietta ice caps. The results were represented in the form of glacier change maps with 50-m grid at 1:200,000 scale. The vertical accuracy of glacier change maps proved on several small and large ice caps was given as ± 0.3 m/a rms. Several resultant maps can be accessed at http://dib.joanneum.at/MAIRES/index.php?page=products. Further sub-regional comparison of glacier change maps with climatological, oceanographic, rheological, gravimetric and other ground-truth and EO data showed that spatial changes of insular glaciers are closely dependent on the frequency of precipitation events, water depth, sea ice regime, polynyas and gravity anomalies nearby. New opportunities for validating mass changes on the largest study glaciers and determining their bulk density are expected from the next

  4. Foreword

    NASA Astrophysics Data System (ADS)

    Boutron, Claude; Ferrari, Christophe

    2003-05-01

    Informatique, Biologie et Médecine, et Sciences de la Terre et de l'Univers. Il y a deux grandes Universités Scientifiques de renommée internationale: l'Université Joseph Fourier (UJF) et l'Institut National Polytechnique de Grenoble (INPG). Il y a aussi d'importants laboratoires de différents organismes publics français et européen comme le Commissariat à l'Énergie Atomique (CEA), le Centre National de la Recherche Scientifique (CNRS), l'Institut Laue Langevin (ILL), l'European Synchrotron Radiation Facility (ESRF) et l'Institut de Radio-Astronomie Millimètrique (IRAM). C'est aussi le lieu d'implantation de nombreuses sociétés de haute technologie comme Hewlett Packard, ST Microelectronics, Schneider Electric and SGS-Thomson. Il a à Grenoble une longue tradition de recherches dans le domaine des métaux lourds dans l'environnement, notamment au Laboratoire de Glaciologie et Géophysique de l'Environnement et au Laboratoire de Géophysique Interne et Tectonophysique. Ces deux volumes regroupent les articles issus de communication présentées aussi bien au cours des sessions orales que des sessions posters. Ces articles sont classés selon l'ordre alphabétique du nom de famille du premier auteur. Nous remercions vivement les auteurs pour l'excellente qualité de ces articles. Nous remercions aussi tout particulièrement Isabelle Houlbert et Laurence Castagné pour leur collaboration. Nous aimerions aussi remercier les membres du comité d'organisation ainsi que Jerome Nriagu (organisateur de la 11e conférence) pour l'aide apportée à l'organisation de cette conférence. Nous remercions aussi tout spécialement Christine Echevet qui n'a pas ménagé ses efforts pour faire de cette conférence un succés, ainsi que de nombreux collègues du Laboratoire de Glaciologie et Géophysique de l'Environnement, en particulier Jocelyne Roquemora. Nous tenons également à remercier le Président de Grenoble Alpes Métropole et le Maire de la Ville de Grenoble pour leur

  5. SUSTAINABILITY EFFECTS OF Crotalaria juncea L. AND Crotalaria spectabilis ROTH ON SOIL FERTILITY AND SOIL CONSERVATION

    NASA Astrophysics Data System (ADS)

    László, Márton, ,, Dr.

    2010-05-01

    agricultural production becomes a great possibility for Hungary and the international community. In this process a green manure crop application for example crotalaria get a great chance for improvement process on soil fertility and soil coservation (Lazányi 1998, Márton 1999). This paper briefly outlines the major effects of Crotalaria juncea L. and Crotalaria spectabilis ROTH on soil fertility and soil conservation. MATERIAL AND METHOD Field experiment were carried out on a calcareous chernozem soil at Hungary (Experiment station Nagyhörcsök of Research Iinstitute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences) in partly of experiments series (3 years) in 1998. The soil with about 20% clay, 3% humus, 5 Ca CO3 in its ploughed layer. To ensure a sufficient macronutrient supply in the whole experiment, 100 kg N, 100 kg P2O5 and 100 kg K2O are given hectare in autumn of 1997. The Crotalaria juncea L. and Crotalaria spectabilis ROTH were applied with 2 replications. Each plot has an area of 45 m2 with 230-230 individual plants. Winter wheat was grown as a green crop (preceding the main product of a field) with commonly used agrotechnic. Soil samples are taken before the experiment set up on 27.04. 1998. Each composite sample consist of 20 subsamples drawn from the plow layer of each plot. Plant samples are taken during the vegetation period at least twice (20.07. 1998 and 02.11. 1998), using 5-5 plants per plot randomly. Plant material is dried, milled and digested in teflon bombs using cc.HNO3+cc.H2O2 and their total macro and microelement content with the exception of N was determined by ICP technics (JY 238 ULTRACE). N-content were determined by titration of hypobromit after the cc.H2SO4+cc.H2O2 digestion, N-NO3 content were determined by Griess-Ilosvai reaction after water extraction. Soil samples are extracted by ammonium-acetate+EDTA (Lakanen and Erviö 1971) and their available element content with the exception of N is mesaured using

  6. Extrasolar Planet in Double Star System Discovered from La Silla

    NASA Astrophysics Data System (ADS)

    1998-11-01

    fact a long-period "spectroscopic" binary system. The separation between the two stars is probably more than one hundred times larger than that between the planet and the star it revolves around. The observed characteristics of the new planet, e.g., its rather large mass and almost circular orbit, associated with this double-star nature, indicate that planetary systems may form in other ways than the standard agglomeration scheme. For instance, recent theoretical calculations by Alan Boss (Carnegie Institute of Washington, USA) suggest that multi-Jupiter-mass planets may be formed through dynamical instabilities in a protoplanetary disk that are induced by the gravitational action of a nearby stellar companion. One important result of this new, extensive survey carried out in the southern sky will be to provide potential targets for the VLTI (Very Large Telescope Interferometer), presently being built by ESO on Cerro Paranal. When it enters into operation some years from now, it will be able to provide exciting additional information about these planets and their nature. Note: [1] The team consists of Didier Queloz (also Jet Propulsion Laboratory, Pasadena, USA), Michel Mayor, Luc Weber, Dominique Naef, Stephane Udry, Nuno Santos, Andre Blecha and Michel Burnet (Geneva Observatory, Switzerland) and Bastien Confino (St. Luc Observatory, Switzerland). The members of team want to express their gratitude to all the technical staff of the Geneva Observatory, in particular Daniel Huguenin, Rene Dubosson, Giovanni Russiniello and Charles Maire for their great efforts, from the design to the final installation of the Swiss Leonard Euler telescope at La Silla. How to obtain ESO Press Information ESO Press Information is made available on the World-Wide Web (URL: http://www.eso.org ). ESO Press Photos may be reproduced, if credit is given to the European Southern Observatory.

  7. Greenland plays a large role in the gloomy picture painted of probable future sea-level rise

    NASA Astrophysics Data System (ADS)

    Hanna, Edward

    2012-12-01

    very coarse at 5.625° latitude/longitude resolution. There appears to be a cancelling out of errors in LOVECLIM, where its climate sensitivity seems quite low (in comparison with other models) but the simulated enhanced high-latitude warming—often termed Arctic amplification and evident in observed climate data for the last 30 years—is quite high. It would be good to include precipitation as well as temperature changes when modelling the future response of glaciers, even though the former is likely to be less important. I do not agree that uncertainties in climate sensitivity can be adequately accounted for by varying boundary and initial conditions in ensembles of models, as all of the model simulations may be systematically biased due to some physical effect that is improperly considered—or unrepresented—by all of the models, but this is a widely used technique and probably the best that can be done here. Despite these caveats, Goelzer et al 's (2012) results will undoubtedly prove useful for the Intergovernmental Panel on Climate Change (IPCC)'s upcoming Fifth Assessment Report due to be released in 2014. The key challenge remains to further improve the individual components of the Earth system model, especially those concerning ice-sheet dynamics. Acknowledgments EH thanks Ben Brock, Amy Jowett and Andrew Sole for useful editorial suggestions to the text. References Barletta V R, Sørensen L S and Forsberg R 2012 Variability of mass changes at basin scale for Greenland and Antarctica Cryosp. Discuss. 6 3397-446 Bartholomew I, Nienow P, Sole A, Mair D, Cowton T and King M A 2011 Seasonal variations in Greenland ice sheet motion: inland extent and behaviour at higher elevations Earth Planet. Sci. Lett. 307 271-8 Goelzer H, Huybrechts P, Raper S C B, Loutre M -F, Goosse H and Fichefet T 2012 Millennial total sea-level commitments projected with the Earth system model of intermediate complexity LOVECLIM Environ. Res. Lett. 7 045401 Hanna E, Huybrechts P

  8. An Integrated Biochemistry Laboratory, Including Molecular Modeling

    NASA Astrophysics Data System (ADS)

    Hall, Adele J. Wolfson Mona L.; Branham, Thomas R.

    1996-11-01

    ' work; point out any problems in organization or grammar; and suggest the steps necessary to complete the paper. They then go over the peer review form with the writer, referring any questions or disagreements to the instructor. It is most helpful if the instructor can also read and comment on the draft. General comments on the level of detail included and any problems with the reasoning come more appropriately from the instructor than from peers. The paper is then revised and handed in on the following week. The final draft is accompanied by a summary of revisions and copies of all peer reviews. Students are graded on peer reviews and summaries of revisions and cover letters, as well as on the final paper. Acknowledgments The molecular modeling workstations and associated software were purchased with funding from NSF, Instrumentation and Laboratory Improvement program, grant DUE-9350843 to AJW, with matching funds from Wellesley College. Some of the equipment for protein purification was funded by a grant from the Howard Hughes Medical Institute to Wellesley College. The authors are grateful to Paul Reisberg for helpful discussions in the early stages of this project and to Margaret Merritt for a critical review of the manuscript. Literature Cited 1. Blake, C. C. F.; Jonhson, L. N.; Mair, G. A.; North, A. C. T.; Phillips. D. C.; Sarma, V. R. Proc. Roy. Soc. London Ser. B 1967, 167, 378 - 388. 2. Hendrickson, H. S.; Giannini, J. L.; Bergstrom, J. P.; Johnson, S. N.; Leland, P. A. Biochem. Educ. 1995, 23, 14 - 17. 3. Miranker, A., Robinson, C. V.; Radford, S. E.; Aplin, R. T.; Dobson, C. M. Science 1993, 262, 896 - 900. 4. Turner, M. A.; Howell, P. L. Prot. Sci. 1995, 4, 442 - 449. 5. Radmacher, M.; Fritz, M.; Hansma, H. G.; Hansma, P. Science 1994, 265, 1577 - 1579. 6. Shugar, D. Biochim. Biophys. Acta 1952, 8, 302 - 309. 7. Bradford, M. M. Anal. Biochem. 1976, 72, 248 - 254. 8. Strang, R. H. C. In Practical Biochemistry for Colleges; Wood, E. J., Ed.; Pergamon: Oxford