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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. PMID:22546445

  2. Encounters with aphid predators or their residues impede searching and oviposition by the aphid parasitoid Aphidius ervi (Hymenoptera: Aphidiinae).

    PubMed

    Almohamad, Raki; Hance, Thierry

    2014-04-01

    Intraguild predation (IGP) can be an important factor influencing the effectiveness of aphid natural enemies in biological control. In particular, aphid parasitoid foraging could be influenced by the presence of predators. This study investigated the effect of larvae of the predatory hoverfly Episyrphus balteatus DeGeer (Diptera: Syrphidae) and the multicolored Asian ladybird Harmonia axyridis Pallas (Coleoptera: Coccinellidae) on the foraging behavior of the aphid parasitoid, Aphidius ervi Haliday (Hymenoptera: Aphidiidae) in choice experiments using a leaf disc bioassay. Wasp response to chemical tracks left by those predator larvae was also tested. Parasitoid behavior was recorded using the Observer (Noldus Information Technology, version 5.0, Wageningen, the Netherlands). The experiments were conducted under controlled environmental conditions using leaves of the broad bean plant, Vicia faba L. (Fabaceae) with Myzus persicae Sulzer (Homoptera: Aphididae) as the host complex. A. ervi females avoided aphid patches when larvae of either predator were present. A similar avoidance response was shown by A. ervi to aphid patches with E. balteatus larval tracks, whereas no significant response was observed to tracks left by H. axyridis larvae. It was concluded that IG predator avoidance shown by the aphid parasitoid A. ervi may be a factor affecting their distribution among host patches. PMID:23955963

  3. 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

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. Effects of sub-lethal and lethal doses of lambda-cyhalothrin on oviposition experience and host-searching behaviour of a parasitic wasp, Aphidius ervi.

    PubMed

    Desneux, Nicolas; Pham-Delègue, Minh-Hà; Kaiser, Laure

    2004-04-01

    In many parasitoid species, the recognition of chemical signals is essential to find specific hosts. This function is often impaired by exposure to insecticides that are usually neurotoxic. The behaviour of the Hymenopterous parasitoid Aphidius ervi (Haliday) (Hymenoptera: Aphidiinae) after surviving low doses of the pyrethroid lambda-cyhalothrin was examined in laboratory conditions. The host aphid was Myzus persicae (Sulzer) (Homoptera: Aphididae) on oilseed rape. Parasitoid females were exposed by contact with dry residues of the active ingredient at a lethal dose, LD20, and a sub-lethal dose, LD0.1. In a four-armed olfactometer, untreated and inexperienced females were attracted by the odour of M. persicae-infested plants and previous oviposition experience increased the duration of the attraction response. The response of inexperienced females decreased after an exposure to LD0.1 but not to LD20. No effect was observed when females had an oviposition experience prior to the olfactometer test. The oviposition activity was significantly decreased in the LD20-treated group but not in the LD0.1-treated one. All effects disappeared within 24h. Our work shows that orientation and oviposition behaviours may be impaired by low doses of lambda-cyhalothrin, depending on the dose, the parasitoid experience and the type of behaviour.

  9. [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.

  10. 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

  11. [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.

  12. 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

    2016-01-01

    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

  13. Morphological characterization of the mycorrhiza formed by Helianthemum almeriense Pau with Terfezia claveryi Chatin and Picoa lefebvrei (Pat.) Maire.

    PubMed

    Gutiérrez, A; Morte, A; Honrubia, M

    2003-12-01

    This work presents the first anatomical description of the mycorrhizal systems of Helianthemum almeriense, and of the structure and ultrastructure of the mycorrhizae formed by this plant species with the ascomycetes Terfezia claveryi and Picoa lefebvrei. Four different mycorrhizal systems are described, the club-shaped mycorrhiza being the most abundant. The type of mycorrhiza formed depended on the mycorrhiza culture conditions, but not on the fungal species. For both fungal species, H. almeriense formed an endomycorrhiza in natural field conditions, an ecto- and ectendomycorrhiza without a sheath in pot cultures, and an ectomycorrhiza with a characteristic sheath and Hartig net in in vitro cultures. This is the first report of a typical sheath in Helianthemum-desert truffle mycorrhizal associations. The results support the idea that culture conditions can induce changes in mycorrhiza morphology and that there is no clear barrier between the two main types of mycorrhiza organization in Helianthemum species. The ultrastructural study confirmed the regular presence of T. claveryi intracellular hyphae in direct contact with the host wall, a localization which seems to be a characteristic of the T. claveryi mycorrhiza organization. The P. lefebvrei mycorrhiza organization was characterized by intracellular hyphae with large amounts of electron-dense globules, probably with a lipidic content, and a warty ornamentation on the wall of the root external hyphae.

  14. Influence of salt stress on essential oil yield and composition of lemon grass (Cymbopogon schoenanthus L. Spreng. ssp. Laniger (Hook) Maire et Weil).

    PubMed

    Khadhri, Ayda; Neffati, Mohamed; Smiti, Samira; Nogueira, José Manuel F; Araujo, Maria Eduarda M

    2011-01-01

    Cymbopogon is an aromatic plant valued for its citrus scent aroma. In this article, the effect of saline irrigation water on yield and quality of Cymbopogon schoenanthus L. was evaluated. Compounds of essential oils were identified by gas chromatography-mass spectrometry and/or (13)C-NMR spectroscopy. Results showed that the growth of the aerial part was not affected at a concentration of 50 mmol NaCl. Under salt stress, the content of major chemical compounds was affected differently by the treatment level.

  15. 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. PMID:25977054

  16. 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…

  17. Specificity of Multi-Modal Aphid Defenses against Two Rival Parasitoids.

    PubMed

    Martinez, Adam J; Kim, Kyungsun L; Harmon, Jason P; Oliver, Kerry M

    2016-01-01

    Insects are often attacked by multiple natural enemies, imposing dynamic selective pressures for the development and maintenance of enemy-specific resistance. Pea aphids (Acyrthosiphon pisum) have emerged as models for the study of variation in resistance against natural enemies, including parasitoid wasps. Internal defenses against their most common parasitoid wasp, Aphidius ervi, are sourced through two known mechanisms- 1) endogenously encoded resistance or 2) infection with the heritable bacterial symbiont, Hamiltonella defensa. Levels of resistance can range from nearly 0-100% against A. ervi but varies based on aphid genotype and the strain of toxin-encoding bacteriophage (called APSE) carried by Hamiltonella. Previously, other parasitoid wasps were found to commonly attack this host, but North American introductions of A. ervi have apparently displaced all other parasitoids except Praon pequodorum, a related aphidiine braconid wasp, which is still found attacking this host in natural populations. To explain P. pequodorum's persistence, multiple studies have compared direct competition between both wasps, but have not examined specificity of host defenses as an indirectly mediating factor. Using an array of experimental aphid lines, we first examined whether aphid defenses varied in effectiveness toward either wasp species. Expectedly, both types of aphid defenses were effective against A. ervi, but unexpectedly, were completely ineffective against P. pequodorum. Further examination showed that P. pequodorum wasps suffered no consistent fitness costs from developing in even highly 'resistant' aphids. Comparison of both wasps' egg-larval development revealed that P. pequodorum's eggs have thicker chorions and hatch two days later than A. ervi's, likely explaining their differing abilities to overcome aphid defenses. Overall, our results indicate that aphids resistant to A. ervi may serve as reservoirs for P. pequodorum, hence contributing to its persistence in

  18. 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...

  19. Specificity of Multi-Modal Aphid Defenses against Two Rival Parasitoids

    PubMed Central

    Martinez, Adam J.; Kim, Kyungsun L.; Harmon, Jason P.; Oliver, Kerry M.

    2016-01-01

    Insects are often attacked by multiple natural enemies, imposing dynamic selective pressures for the development and maintenance of enemy-specific resistance. Pea aphids (Acyrthosiphon pisum) have emerged as models for the study of variation in resistance against natural enemies, including parasitoid wasps. Internal defenses against their most common parasitoid wasp, Aphidius ervi, are sourced through two known mechanisms– 1) endogenously encoded resistance or 2) infection with the heritable bacterial symbiont, Hamiltonella defensa. Levels of resistance can range from nearly 0–100% against A. ervi but varies based on aphid genotype and the strain of toxin-encoding bacteriophage (called APSE) carried by Hamiltonella. Previously, other parasitoid wasps were found to commonly attack this host, but North American introductions of A. ervi have apparently displaced all other parasitoids except Praon pequodorum, a related aphidiine braconid wasp, which is still found attacking this host in natural populations. To explain P. pequodorum’s persistence, multiple studies have compared direct competition between both wasps, but have not examined specificity of host defenses as an indirectly mediating factor. Using an array of experimental aphid lines, we first examined whether aphid defenses varied in effectiveness toward either wasp species. Expectedly, both types of aphid defenses were effective against A. ervi, but unexpectedly, were completely ineffective against P. pequodorum. Further examination showed that P. pequodorum wasps suffered no consistent fitness costs from developing in even highly ‘resistant’ aphids. Comparison of both wasps’ egg-larval development revealed that P. pequodorum’s eggs have thicker chorions and hatch two days later than A. ervi’s, likely explaining their differing abilities to overcome aphid defenses. Overall, our results indicate that aphids resistant to A. ervi may serve as reservoirs for P. pequodorum, hence contributing to

  20. 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.

  1. 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. Strangelove,""Citizen Kane"…

  2. A CRTCal link between energy and life span.

    PubMed

    Brunet, Anne

    2011-04-01

    Cutting down calories prolongs life, but how this works remains largely unknown. A recent study in Nature (Mair et al., 2011) shows that life span extension triggered by the energy-sensing protein kinase AMPK is mediated by an evolutionarily conserved transcriptional circuit involving CRTC-1 and CREB.

  3. 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);…

  4. 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.

  5. 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. PMID:26961124

  6. 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.

  7. Devising an indicator to detect mid-term abortions in dairy cattle: a first step towards syndromic surveillance of abortive diseases.

    PubMed

    Bronner, Anne; Morignat, Eric; Hénaux, Viviane; Madouasse, Aurélien; Gay, Emilie; Calavas, Didier

    2015-01-01

    Bovine abortion surveillance is essential for human and animal health because it plays an important role in the early warning of several diseases. Due to the limited sensitivity of traditional surveillance systems, there is a growing interest for the development of syndromic surveillance. Our objective was to assess whether, routinely collected, artificial insemination (AI) data could be used, as part of a syndromic surveillance system, to devise an indicator of mid-term abortions in dairy cattle herds in France. A mid-term abortion incidence rate (MAIR) was computed as the ratio of the number of mid-term abortions to the number of female-weeks at risk. A mid-term abortion was defined as a return-to-service (i.e., a new AI) taking place 90 to 180 days after the previous AI. Weekly variations in the MAIR in heifers and parous cows were modeled with a time-dependent Poisson model at the département level (French administrative division) during the period of 2004 to 2010. The usefulness of monitoring this indicator to detect a disease-related increase in mid-term abortions was evaluated using data from the 2007-2008 episode of bluetongue serotype 8 (BT8) in France. An increase in the MAIR was identified in heifers and parous cows in 47% (n = 24) and 71% (n = 39) of the departements. On average, the weekly MAIR among heifers increased by 3.8% (min-max: 0.02-57.9%) when the mean number of BT8 cases that occurred in the previous 8 to 13 weeks increased by one. The weekly MAIR among parous cows increased by 1.4% (0.01-8.5%) when the mean number of BT8 cases occurring in the previous 6 to 12 weeks increased by one. These results underline the potential of the MAIR to identify an increase in mid-term abortions and suggest that it is a good candidate for the implementation of a syndromic surveillance system for bovine abortions. PMID:25746469

  8. Devising an indicator to detect mid-term abortions in dairy cattle: a first step towards syndromic surveillance of abortive diseases.

    PubMed

    Bronner, Anne; Morignat, Eric; Hénaux, Viviane; Madouasse, Aurélien; Gay, Emilie; Calavas, Didier

    2015-01-01

    Bovine abortion surveillance is essential for human and animal health because it plays an important role in the early warning of several diseases. Due to the limited sensitivity of traditional surveillance systems, there is a growing interest for the development of syndromic surveillance. Our objective was to assess whether, routinely collected, artificial insemination (AI) data could be used, as part of a syndromic surveillance system, to devise an indicator of mid-term abortions in dairy cattle herds in France. A mid-term abortion incidence rate (MAIR) was computed as the ratio of the number of mid-term abortions to the number of female-weeks at risk. A mid-term abortion was defined as a return-to-service (i.e., a new AI) taking place 90 to 180 days after the previous AI. Weekly variations in the MAIR in heifers and parous cows were modeled with a time-dependent Poisson model at the département level (French administrative division) during the period of 2004 to 2010. The usefulness of monitoring this indicator to detect a disease-related increase in mid-term abortions was evaluated using data from the 2007-2008 episode of bluetongue serotype 8 (BT8) in France. An increase in the MAIR was identified in heifers and parous cows in 47% (n = 24) and 71% (n = 39) of the departements. On average, the weekly MAIR among heifers increased by 3.8% (min-max: 0.02-57.9%) when the mean number of BT8 cases that occurred in the previous 8 to 13 weeks increased by one. The weekly MAIR among parous cows increased by 1.4% (0.01-8.5%) when the mean number of BT8 cases occurring in the previous 6 to 12 weeks increased by one. These results underline the potential of the MAIR to identify an increase in mid-term abortions and suggest that it is a good candidate for the implementation of a syndromic surveillance system for bovine abortions.

  9. Devising an Indicator to Detect Mid-Term Abortions in Dairy Cattle: A First Step Towards Syndromic Surveillance of Abortive Diseases

    PubMed Central

    Bronner, Anne; Morignat, Eric; Hénaux, Viviane; Madouasse, Aurélien; Gay, Emilie; Calavas, Didier

    2015-01-01

    Bovine abortion surveillance is essential for human and animal health because it plays an important role in the early warning of several diseases. Due to the limited sensitivity of traditional surveillance systems, there is a growing interest for the development of syndromic surveillance. Our objective was to assess whether, routinely collected, artificial insemination (AI) data could be used, as part of a syndromic surveillance system, to devise an indicator of mid-term abortions in dairy cattle herds in France. A mid-term abortion incidence rate (MAIR) was computed as the ratio of the number of mid-term abortions to the number of female-weeks at risk. A mid-term abortion was defined as a return-to-service (i.e. a new AI) taking place 90 to 180 days after the previous AI. Weekly variations in the MAIR in heifers and parous cows were modeled with a time-dependent Poisson model at the département level (French administrative division) during the period of 2004 to 2010. The usefulness of monitoring this indicator to detect a disease-related increase in mid-term abortions was evaluated using data from the 2007–2008 episode of bluetongue serotype 8 (BT8) in France. An increase in the MAIR was identified in heifers and parous cows in 47% (n = 24) and 71% (n = 39) of the départements. On average, the weekly MAIR among heifers increased by 3.8% (min-max: 0.02–57.9%) when the mean number of BT8 cases that occurred in the previous 8 to 13 weeks increased by one. The weekly MAIR among parous cows increased by 1.4% (0.01–8.5%) when the mean number of BT8 cases occurring in the previous 6 to 12 weeks increased by one. These results underline the potential of the MAIR to identify an increase in mid-term abortions and suggest that it is a good candidate for the implementation of a syndromic surveillance system for bovine abortions. PMID:25746469

  10. Tierra del Fuego, Argentina, South America

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Mitre Peninsula is the easternmost tip of Tierra del Fuego, Argentina, (54.5S, 65.5W). Early winter snow can be seen on this south tip of the Andes Mountains. These same mountains continue underwater to Antarctica. The Strait of Magellan, separating the South American mainland from Tierra del Fuego is off the scene to the north and west, but the Strait of LeMaire, separating Tierra del Fuego from the Isla de los Estados can be seen.

  11. 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

  12. 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.

  13. 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. PMID:25197882

  14. 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.

  15. Population dynamics of defensive symbionts in aphids.

    PubMed

    Oliver, Kerry M; Campos, Jaime; Moran, Nancy A; Hunter, Martha S

    2008-02-01

    Vertically transmitted micro-organisms can increase in frequency in host populations by providing net benefits to hosts. While laboratory studies have identified diverse beneficial effects conferred by inherited symbionts of insects, they have not explicitly examined the population dynamics of mutualist symbiont infection within populations. In the pea aphid, Acyrthosiphon pisum, the inherited facultative symbiont, Hamiltonella defensa, provides protection against parasitism by the wasp, Aphidius ervi. Despite a high fidelity of vertical transmission and direct benefits of infection accruing to parasitized aphids, Hamiltonella remains only at intermediate frequencies in natural populations. Here, we conducted population cage experiments to monitor the dynamics of Hamiltonella and of another common A. pisum symbiont, Serratia symbiotica, in the presence and absence of parasitism. We also conducted fitness assays of Hamiltonella-infected aphids to search for costs to infection in the absence of parasitism. In the population cages, we found that the frequency of A. pisum infected with Hamiltonella increased dramatically after repeated exposure to parasitism by A. ervi, indicating that selection pressures from natural enemies can lead to the increase of particular inherited symbionts in insect populations. In our laboratory fitness assays, we did not detect a cost to infection with Hamiltonella, but in the population cages not exposed to parasitism, we found a significant decline in the frequency of both Hamiltonella and Serratia. The declining frequencies of Hamiltonella-infected aphids in population cages in the absence of parasitism indicate a probable cost to infection and may explain why Hamiltonella remains at intermediate frequencies in natural populations.

  16. 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

  17. Parasitoid wasps influence where aphids die via an interspecific indirect genetic effect.

    PubMed

    Khudr, Mouhammad Shadi; Oldekop, Johan A; Shuker, David M; Preziosi, Richard F

    2013-06-23

    Host-parasite interactions are a key paradigm for understanding the process of coevolution. Central to coevolution is how genetic variation in interacting species allows parasites to evolve manipulative strategies. However, genetic variation in the parasite may also be associated with host phenotype changes, thereby changing the selection on both species. For instance, parasites often induce changes in the behaviour of their host to maximize their own fitness, yet the quantitative genetic basis for behavioural manipulation has not been fully demonstrated. Here, we show that the genotype of the parasitoid wasp Aphidius ervi has a significant effect on where its aphid host Acyrthosiphon pisum moves to die following parasitism, including the likelihood that the aphid abandons the plant. These results provide a clear example of an interspecific indirect genetic effect whereby the genetics of one species influences the expression of a specific behavioural trait in another.

  18. 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.

  19. 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

  20. 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.

  1. [Marcel Petitmengin (1881-1908), pharmacist botanist: his life, his work].

    PubMed

    Larnaudie, S; Labrude, P

    1999-01-01

    Marcel Petitmengin was born in Nancy in January 1881. Student at the school of pharmacy and preparator in its laboratory for natural history, he received his diploma in 1904. He had already published some papers on botany and belonged to the International Academy for Geographical botany. He choose the flora of Mount Viso, in Italy, for his philosophical thesis. In the same time, he worked on greek flora with Maire, then on Primulaceae from Asia. Having published about fifty papers on botany, he died from tuberculosis in October 1908, being twenty-seven years old. Very faithful, he took part actively in protestantism in Nancy.

  2. A two dimensional nodal Riemann solver based on one dimensional Riemann solver for a cell-centered Lagrangian scheme

    NASA Astrophysics Data System (ADS)

    Liu, Yan; Shen, Weidong; Tian, Baolin; Mao, De-kang

    2015-03-01

    We develop a new and more general formula for the construction of two dimensional nodal Riemann solver for a cell-centered Lagrangian scheme developed by Maire and his co-workers which allows us to use general one dimensional Riemann solvers that have intermediate velocity and pressure in the construction. The old formula for the scheme used in the papers of Maire et al. is only a special case of our new formula. We present an entropy discussion, which indicates that the schemes with nodal solvers constructed following the old formula, which can only use the 1D Riemann solvers satisfying our strong entropy condition, are usually numerically very dissipative. To develop numerically less dissipative schemes we introduce a so-called weak entropy condition, and present a one dimensional Riemann solver that satisfies the weak entropy condition but not the strong entropy condition. Analysis shows that the scheme using this 1D solver is numerically less dissipative than the schemes using solvers satisfying the strong condition. Finally, several numerical examples are presented to show that our new formula works well and the scheme using the one dimensional solver satisfying the weak entropy condition improves the accuracy in smooth region, resolution around rarefaction waves and two dimensional symmetry; however it sometimes produces small velocity oscillations and mesh distortions.

  3. Theoretical study and prediction of BVI noise including close interactions

    NASA Astrophysics Data System (ADS)

    Spiegel, Pierre; Rahier, Gilles

    1991-05-01

    The following study deals with the highly impulsive blade-vortex interaction (BVI) noise which is generated by helicopter main rotors in descent flight. Two computer codes have been especially designed to predict it at reduced computing costs, starting from given vortices. The aerodynamic code, called MAIR, predicts the unsteady airloads, even for head-on collisions, by using a singularity method and modeling the vortices as cloud vortices with viscous cores. The acoustic code, called PARIS, computes the resulting radiated loading noise and is based on the Ffowcs Williams and Hawkings equation. These two codes are ready to perform noise prediction in the flight cases but the vortex prediction required for input data still needs to be improved. While waiting for better wake data, the two codes have been used for a theoretical parametric study of arbitrary single blade-vortex interactions. This study gives a physical insight of the phenomenon and its predicted tendencies could help designing quieter blades.

  4. Evaluation of Mycelial Nutrients, Bioactive Compounds, and Antioxidants of Five Himalayan Entomopathogenic Ascomyceteous Fungi from India.

    PubMed

    Sharma, Sapan Kumar; Gautam, Nandini; Atri, Narender Singh

    2015-01-01

    In this study, using standard methods, mycelial nutrients, bioactive compounds, and antioxidants were analyzed for the first time for five fungal species: Isaria sinclairii (Berk.) Lloyd, I. tenuipes Peck, I. japonica Yasuda, I. farinosa (Holmsk) Fr. and Cordyceps tuberculata (Lebert) Maire. All of these species were low in fat content and rich in protein, fiber, ash, and carbohydrates. Mineral elements (Fe, Mg, Cu, Mn, and Ca) were detected in appreciable amounts. All three types of fatty acids (saturated, monounsaturated, and polyunsaturated) as well as bioactive compounds (ascorbic acid, β-carotene, lycopene, phenolic compounds, and polysaccharides) were detected for each species. The investigated species showed high ferric-reducing antioxidant power as well as 2,2-diphenyl-1-picryl-hydrazyl radical scavenging activity. Although differences were observed in the values of each species, each species showed richness in one or more components. PMID:26559700

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. Tomato below ground-above ground interactions: Trichoderma longibrachiatum affects the performance of Macrosiphum euphorbiae and its natural antagonists.

    PubMed

    Battaglia, Donatella; Bossi, Simone; Cascone, Pasquale; Digilio, Maria Cristina; Prieto, Juliana Duran; Fanti, Paolo; Guerrieri, Emilio; Iodice, Luigi; Lingua, Guido; Lorito, Matteo; Maffei, Massimo E; Massa, Nadia; Ruocco, Michelina; Sasso, Raffaele; Trotta, Vincenzo

    2013-10-01

    Below ground and above ground plant-insect-microorganism interactions are complex and regulate most of the developmental responses of important crop plants such as tomato. We investigated the influence of root colonization by a nonmycorrhizal plant-growth-promoting fungus on direct and indirect defenses of tomato plant against aphids. The multitrophic system included the plant Solanum lycopersicum ('San Marzano nano'), the root-associated biocontrol fungus Trichoderma longibrachiatum strain MK1, the aphid Macrosiphum euphorbiae (a tomato pest), the aphid parasitoid Aphidius ervi, and the aphid predator Macrolophus pygmaeus. Laboratory bioassays were performed to assess the effect of T. longibrachiatum MK1, interacting with the tomato plant, on quantity and quality of volatile organic compounds (VOC) released by tomato plant, aphid development and reproduction, parasitoid behavior, and predator behavior and development. When compared with the uncolonized controls, plants whose roots were colonized by T. longibrachiatum MK1 showed quantitative differences in the release of specific VOC, better aphid population growth indices, a higher attractiveness toward the aphid parasitoid and the aphid predator, and a quicker development of aphid predator. These findings support the development of novel strategies of integrated control of aphid pests. The species-specific or strain-specific characteristics of these below ground-above ground interactions remain to be assessed.

  10. 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

  11. 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

  12. 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

  13. Shallot Aphids, Myzus ascalonicus, in Strawberry: Biocontrol Potential of Three Predators and Three Parasitoids

    PubMed Central

    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

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  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. Air and silica core Bragg fibers for radiation delivery in the wavelength range 0.6-1.5 μ m

    NASA Astrophysics Data System (ADS)

    Frank, Milan; Jelínek, Michal; Kubeček, Václav; Kašík, Ivan; Podrazký, Ondřej; Matějec, Vlastimil

    2016-09-01

    This paper presents fundamental characteristics of laboratory designed and fabricated Bragg fibers with air and silica cores at wavelengths of 632, 975, 1064 and 1550 nm. Fibers with the 26- μ m-silica core and 5- or 73- μ m-air cores in diameters and claddings of 3 pairs of Bragg layers were prepared from one preform. The overall transmittance, attenuation coefficients, coupling losses, bending losses, and damage-intensity thresholds were determined using four continuous-wave laser sources with the maximum output power of 300 mW and a pulsed 9 ns laser with the maximum output energy up to 1 mJ. The lowest attenuation coefficient of about 70 dB/km was determined at 1064 nm with the 73- μ m-air-core Bragg fiber. All fibers have been found to exhibit negligible bending losses down to the bending diameters of 5 cm. In comparison with the conventional gradient optical fiber, all the prepared Bragg fibers have approximately six times higher damage intensity threshold of about 30 GWcm-2 and therefore they are very suitable for high power laser radiation delivery.

  2. A robust method to screen detergents for membrane protein stabilization, revisited.

    PubMed

    Champeil, Philippe; Orlowski, Stéphane; Babin, Simon; Lund, Sten; le Maire, Marc; Møller, Jesper; Lenoir, Guillaume; Montigny, Cédric

    2016-10-15

    This report is a follow up of our previous paper (Lund, Orlowski, de Foresta, Champeil, le Maire and Møller (1989), J Biol Chem 264:4907-4915) showing that solubilization in detergent of a membrane protein may interfere with its long-term stability, and proposing a protocol to reveal the kinetics of such irreversible inactivation. We here clarify the fact that when various detergents are tested for their effects, special attention has of course to be paid to their critical micelle concentration. We also investigate the effects of a few more detergents, some of which have been recently advertised in the literature, and emphasize the role of lipids together with detergents. Among these detergents, lauryl maltose neopentyl glycol (LMNG) exerts a remarkable ability, even higher than that of β-dodecylmaltoside (DDM), to protect our test enzyme, the paradigmatic P-type ATPase SERCA1a from sarcoplasmic reticulum. Performing such experiments for one's favourite protein probably remains useful in pre-screening assays testing various detergents. PMID:27443956

  3. 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.

  4. 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. PMID:25500156

  5. 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.

  6. 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.

  7. High- and low-frequency noise in Cs and in liquid metal ion sources.

    PubMed

    Rüdenauer, F; Mitterauer, J; Genovese, A

    2009-04-01

    Fundamental Physics space missions set rigid thrust noise limits for liquid metal ion thrusters used as actuators on drag-free platforms aboard the spacecraft. We have measured current-, voltage- and thrust noise of Cs and In LMIS, foreseen as prime candidates in these missions. In the high-frequency range, quasiperiodic oscillations around approximately 10(5)Hz can be observed for both types of emitters with frequency depending on emission current. In the low-frequency range (1-10(-3)Hz), which is particularly important for drag-free control, different types of noise events are observed, which in some instances show definite signs of deterministic chaos (period doubling, self-similarity). High-frequency current oscillations are generally ascribed to electro-hydrodynamic oscillations of the TAYLOR cone and the jet at its apex, with concomitant emission of charged nanodroplets. Comparison of theory and experiment shows unsatisfactory agreement in predicted vs. measured current oscillation frequencies and large disagreement in droplet emission frequencies. No theory is presently available for describing low-frequency noise events. In terms of a linearized Mair theory it is, however, shown that these noise events can be efficiently described by spontaneous variations in electrical emitter impedance. In spite of this impedance noise, the mission requirements for thrust noise (<0.1microN/Hz(1/2)) can be met by a thrust-stabilized In emitter.

  8. 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.

  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. 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

  11. 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

  12. 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

  13. Comparative effects of auxin transport inhibitors on rhizogenesis and mycorrhizal establishment of spruce seedlings inoculated with Laccaria bicolor.

    PubMed

    Rincón, Ana; Priha, Outi; Sotta, Bruno; Bonnet, Magda; Le Tacon, François

    2003-08-01

    We compared the effects of two auxin transport inhibitors (2,3,5-triiodobenzoic acid (TIBA) and 1-N-naphthylphthalamic acid (NPA)) on rhizogenesis and mycorrhizal establishment of Picea abies L. (Karst.) seedlings inoculated with Laccaria bicolor S238N (Maire) Orton. Inoculation of seedlings with L. bicolor under in vitro conditions strongly increased host root and shoot growth. Although TIBA had no effect on taproot growth, NPA decreased taproot growth and deformed the root apex into a globular shape in both non-inoculated seedlings and seedlings inoculated with L. bicolor. Inoculation with L. bicolor strongly increased lateral rhizogenesis of the seedlings, and application of 100 microM indole-3-acetic acid (IAA) partially reproduced this effect. Although TIBA completely inhibited the stimulatory effect of L. bicolor on lateral root formation, NPA inhibited it only partially. Both TIBA and NPA counteracted the effect of exogenous IAA on lateral rhizogenesis. Inoculation with L. bicolor significantly increased shoot growth and seedling dry biomass, whereas application of exogenous IAA had no effect on either parameter. There was no effect of NPA on shoot growth and biomass production. The presence of TIBA completely prevented the development of ectomycorrhizal structures (mantle and Hartig net). In the presence of NPA, the number of seedlings colonized by the fungus was reduced and the degree of development of ectomycorrhizal structures was variable, but not completely prevented. In medium lacking tryptophan, neither TIBA nor NPA inhibited the release of IAA produced by L. bicolor in pure culture. When 100 microM tryptophan was added to the medium, TIBA significantly increased the amount of IAA released by the fungus, whereas NPA had no significant effect. We conclude that fungal IAA plays an important role in plant rhizogenesis and in the establishment of ectomycorrhizal symbiosis.

  14. 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.

  15. All-trans-Retinoic Acid and Erk1/2 Signaling Synergistically Regulate the Expression of CD300B in Human Monocytic Cells

    PubMed Central

    Wu, Yong; Chen, Qiuyan; Pai, Tongkun; Ross, A. Catharine

    2011-01-01

    The regulation of the cell-surface receptors that constitute the gene cluster, CD300, also known as the Myeloid Activating/Inhibitory Receptor (MAIR) family, is poorly understood. In the present study, we tested the hypothesis that all-trans-RA (RA), a bioactive form of vitamin A long recognized for its role in regulation of immune cell activities, may be a potent regulator of the expression of human CD300B. In monocytic THP-1 cells, RA (20 nM) alone significantly increased CD300B mRNA within 2 h and up to 20-fold after 24 h; however, CD300B protein determined by flow cytometry and confocal microscopy showed little change. A search for coactivating molecules revealed that phorbol myristyl acetate (PMA), a mimetic of diacylglycerol, alone increased CD300B mRNA by less than 5-fold; however, the combination of at-RA and PMA increased CD300B mRNA nearly 60-fold. Moreover, CD300B protein was increased. CD300B molecules were mainly located on the plasma membrane and in the endosomal compartment, sharing a distribution/recycling pattern similar to transferrin receptor CD71. The induction of CD300B mRNA by PMA required signaling through the MEK/ERK branch of the MAP kinase pathway, as PD98059, a MEK1/2 inhibitor, abrogated this response, while SB203580, an inhibitor of the p38 pathway, had no effect. Our data suggest a model in which RA alone induces a CD300B mRNA response in which transcripts accumulate but remain untranslated and therefore “sterile,” whereas RA combined with signals from the ERK1/2 pathway results in both increased CD300B transcription and protein expression on the cell surface and in endocytic vesicles. PMID:21450279

  16. 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.

  17. Intramedullary spinal cord metastasis as a first manifestation of a renal cell carcinoma: report of a case and review of the literature.

    PubMed

    Schijns, O E; Kurt, E; Wessels, P; Luijckx, G J; Beuls, E A

    2000-12-01

    The authors report the case of a 70-year-old woman who developed a Brown-Sequard-syndrome within 6 weeks caused by an intramedullary spinal cord metastasis of an occult renal cell carcinoma. Intramedullary metastases are rare and represent only 4-8.5% of central nervous system metastases. An important feature of intramedullary metastases is the rapid progression of neurological deficits which necessitates rapid treatment. There are only eight earlier reports of intramedullary metastasis due to renal cell carcinoma (Schiff D, O'Neill BP. Intramedullary spinal cord metastases: clinical features and treatment outcome. Neurology 1996;47:906-12; Belz P. Ein Fall von intramedullaerer Grawitz-Metastase im Lumbalmark. Frankfurt Z Pathol 1912;10:431-44; Gaylor JB, Howie JW. Brown-Sequard-syndrome. A case of unusual aetiology. J Neurol Neurosurg Psychiatry 1938;1:301-5; Kawakami Y, Mair WGP. Haematomyelia due to secondary renal carcinoma. Acta Neuro Pathol 1973;26:85-92; Strang RR. Metastatic tumor of the cervical spinal cord. Med J Aust 1962;1:205-6; Von Pfungen. Uber einige Fälle von Haematomyelie nichttraumatischen Ursprungs. Wien Klin Rdsch 1906;20:44-50; Weitzner S. Coexistent intramedullary metastasis and syringomyelia of cervical spinal cord. Report of a case. Neurology 1960;674-8). To the best of our knowledge this is the first report on a patient in whom symptoms from the metastasis of a renal cell carcinoma preceded the detection of the primary tumor. This report presents the clinical, neuroradiological and histopathological findings of an intramedullary metastasis of a renal cell carcinoma and provides an overview of the literature on intramedullary spinal cord metastases.

  18. Growth, compatible solute and salt accumulation of five mycorrhizal fungal species grown over a range of NaCl concentrations.

    PubMed

    Bois, G; Bertrand, A; Piché, Y; Fung, M; Khasa, D P

    2006-03-01

    The oil sand industry in northeastern Alberta produces vast areas of severely disturbed land. The sodicity of these anthropic soils is one of the principal constraints that impede their revegetation. Previous in vitro studies have shown that the ectomycorrhizal fungi Laccaria bicolor (Maire) Orton UAMH 8232 and Hebeloma crustuliniforme (Bull) Quel. UAMH 5247 have certain salt-resistant traits and thus are candidate species for the inoculation of tree seedlings to be outplanted on salt-affected soil. In this study, the in vitro development of these fungi was compared to that of three mycorrhizal fungi [Suillus tomentosus (Kauff.) Sing., Snell and Dick; Hymenoscyphus sp. and Phialocephala sp.] isolated from a sodic site created by Syncrude Canada Ltd. Their growth, osmotica and Na/Cl contents were assessed over a range (0, 50, 100, 200 mM) of NaCl concentrations. After 21 days, the two ascomycetes (Hymenoscyphus sp. and Phialocephala sp.) were shown to be more resistant to the NaCl treatments than the three basidiomycete species. Of the basidiomycetes, L. bicolor was the most sensitive to NaCl stress, while H. crustuliniforme showed greater water stress resistance, and the S. tomentosus isolate exhibited greater Na and Cl filtering capacities and had a better biomass yield over the NaCl gradient tested. Both ascomycetes used mechanisms other than carbohydrate accumulation to palliate NaCl stress. While the Hymenoscyphus isolate accumulated proline in response to NaCl treatments, the darker Phialocephala isolate may have used compounds such as melanin. The basidiomycete species accumulated mainly mannitol and/or proline in response to increasing concentrations of NaCl.

  19. 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.

  20. Sensitivity to orthographic familiarity in the occipito-temporal region.

    PubMed

    Bruno, Jennifer Lynn; Zumberge, Allison; Manis, Franklin R; Lu, Zhong-Lin; Goldman, Jason G

    2008-02-15

    The involvement of the left hemisphere occipito-temporal (OT) junction in reading has been established, yet there is current controversy over the region's specificity for reading and the nature of its role in the reading process. Recent neuroimaging findings suggest that the region is sensitive to orthographic familiarity [Kronbichler, M., Bergmann, J., Hutzler, F., Staffen, W., Mair, A., Ladurner, G., Wimmer, H. 2007. Taxi vs. Taksi: on orthographic word recognition in the left ventral occipito-temporal cortex. Journal of Cognitive Neuroscience 19, 1-11], and the present study tested that hypothesis. Using fMRI, the OT region and other regions in the reading network were localized in 28 adult, right-handed participants. The BOLD signal in these regions was measured during a phonological judgment task (i.e., "Does it sound like a word?"). Stimuli included words, pseudohomophones (phonologically familiar yet orthographically unfamiliar), and pseudowords (phonologically and orthographically unfamiliar) that were matched on lexical properties including sublexical orthography. Relative to baseline, BOLD signal in the OT region was greater for pseudohomophones than for words, suggesting that the region is sensitive to orthographic familiarity at the whole-word level. Further contrasts of orthographic frequency within the word condition revealed increased BOLD signal for low- than high-frequency words. Specialization in the OT region for recognition of frequent letter strings may support the development of reading expertise. Additionally, BOLD signal in the OT region correlates positively with reading efficiency, supporting the idea that this region is a skill zone for reading printed words. BOLD signal in the IFG and STG correlates negatively with reading efficiency, indicating that processing effort in these classic phonological regions is inversely related to reading efficiency. PMID:18180168

  1. 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

  2. Porosity reduction within shear deformation bands in unconsolidated Pleistocene sediments

    NASA Astrophysics Data System (ADS)

    Brandes, Christian; Tanner, David

    2016-04-01

    Deformation bands are important structural elements that occur in the upper crust and develop in porous sandstones and even in unconsolidated sands. In contrast to discrete surfaces such as faults, deformation bands represent tabular zones of continuous displacement over several centimeters (Fossen et al., 2007). We present an outcrop-based study on the internal fabric of shear deformation bands that developed in Pleistocene unconsolidated sands in northern Germany. The deformation bands formed in an extensional stress regime, have a normal sense of displacement in a range of centimeters to decimeters, and form conjugate sets that intersect at angles between 70° and 90° (Brandes & Tanner, 2012). Due to their near-surface position, they are a perfect target for the study of deformation band formation prior to burial and diagenesis. Thin section analysis show a significant pore space reduction from the host sediment to the shear deformation band. The boundary between the host sediment and the shear deformation bands can be very sharp. The grains within the deformation band are of the same grain size as the host sediment. Grain shape varies from angular to well-rounded. Many elliptic grains have a long-axis orientation parallel to the trend of the deformation band. The grains in the analysed thin sections are all intact, i.e., there is no evidence for cataclasis. We believe the shear deformation bands are created by a grain-sliding process that decreases the porosity and leads to a denser packing of the sand. This is a porosity reduction mechanism in sandstone that occurs prior to burial without cataclasis. This can have an impact on fluid-flow in unconsolidated sediments in the near-surface. References: Brandes, C. & Tanner, D.C. (2012) Three-dimensional geometry and fabric of shear deformation bands in unconsolidated Pleistocene sediments. Tectonophysics, 518-521, 84-92. Fossen, H., Schultz, R.A., Shipton, Z.K., & Mair, K. (2007) Deformation bands in sandstone: a

  3. 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

  4. The Effect of Fracture Filler Composition on the Parameters of Shear Deformation Regime

    NASA Astrophysics Data System (ADS)

    Pavlov, D.; Ostapchuk, A.; Batuhtin, I.

    2015-12-01

    RFBR (grant no. 13-05-00780). 1. Mair, K., K. M. Frye, and C. Marone (2002), J.Geophys.Res., 107(B10), 2219. 2. G.G. Kocharyan, V.K. Markov, A.A. Ostapchuk, and D.V. Pavlov (2014), Phys.Mes, 17(2), 123-133.

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. The Perovskite to Post-Perovskite phase transition in Al-bearing (Mg,Fe)SiO3: A XANES in-situ analysis at the Fe K-edge

    NASA Astrophysics Data System (ADS)

    Andrault, D.; Munoz, M.; Bolfan-Casanova, N.; Guignot, N.; Perrillat, J.; Aquilanti, G.; Pascarelli, S.

    2008-12-01

    ). 4. D. Nishio-Hamane, T. Nagai, K. Fujino, Y. Seto, N. Takafuji, Geophys. Res. Lett. 32, L16306 (2005). 5. W. L. Mao et al., PNAS 101, 15867 (2004). 6. J. P. Brodholt, A. R. Oganov, personal communication. 7. S. Ono, A. R. Oganov, T. Koyama, H. Shimizu, Earth Planet. Sci. 246, 326 (2006). 8. N. Guignot, D. Andrault, G. Morard, M. Mezouar, Earth Planet. Sci. 256, 162 (2007). 9. E. Schultz et al., High Press. Res. 25, 71 (2005). 10. S. Pascarelli, O. Mathon, M. Muñoz, T. Mairs, J. Susini, J. Synch. Rad. 13, 351 (2006). 11. M. Muñoz et al., Geochemistry Geophysics Geosystems 7, Q11020 (2006).

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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.

  1. 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