Academic literature on the topic 'Radula (plantes)'

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Journal articles on the topic "Radula (plantes)"

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Bataw, Ali A., and Nesrin K. Shareef. "Foraging Behaviour of Honey Bees Apis mellifera Linn. Visiting The Flowers of Some Wild Plants in Eljabal Alakhder-Libya." Al-Mukhtar Journal of Sciences 33, no. 2 (June 30, 2018): 117–23. http://dx.doi.org/10.54172/mjsc.v33i2.175.

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This study was conducted to identify the foraging behaviour of honey bees Apis mellifera in the search for food during their visit to the wild flower plants Sinapis alba, Pelargonium radula, Malva parviflora and Stachy stournefortii in Eljabal Alakhder region. The results showed differences in the handling time periods with a significant difference between plant flower species. It showed a longer resting period compared with the handling time for flowers of the Pelargonium radula, which recorded the lowest time, also the travelling time of honey bee among the flowers of the plant species showed a significant difference. Stachy stournefortii recorded a longer travelling time with an average of 4.3 seconds, and Pelargonium radula with 3.5 seconds. Apis mellifera showed a different activity among the different flowers in the collection of nectar or pollen during different daytime hours.
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Söderström, Lars, Matt Renner, Anders Hagborg, and Matt Von Konrat. "Notes on Early Land Plants Today. 50. Radula sainsburiana is a synonym of R. helix (Radulaceae, Marchantiophyta)." Phytotaxa 162, no. 4 (March 17, 2014): 239. http://dx.doi.org/10.11646/phytotaxa.162.4.9.

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Sosna, Ireneusz, and Daria Kortylewska. "Estimation of Interstock and Intermediate Stock Usefulness for Summer Pear Cvs. Budded on Two Rootstocks." Journal of Horticultural Research 21, no. 1 (June 1, 2013): 79–82. http://dx.doi.org/10.2478/johr-2013-0011.

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Abstract In order to increase the profitability of pear production, a greater density of weak growing trees per area unit should be planted. In Poland, the most frequently used pear dwarfing rootstocks are quince clones. The main disadvantage of them is a physiological incompatibility with some cultivars. The aim of this study was to evaluate the effect of the rootstock, interstock, and intermediate stock on growth and productivity of two summer pear cultivars, which are not compatible with the quince rootstock. Twoyear- old pear trees of ‘Radana’ and ‘Clapp’s Favourite’ cvs of different compositions were planted in the spring 2006. The following combinations were evaluated: ‘Radana’ and ‘Clapp’s Favourite’ on Caucasian pear seedlings, ‘Radana’ and ‘Clapp’s Favourite’ on quince SI with an intermediate stem piece of ’Doyenne du Comice’ and ‘Radana’ on Caucasian pear with ‘Pyrodwarf’ interstock. Up to the 6th year after planting, trees of ‘Radana’ grafted on Caucasian pear seedlings and on quince with intermediate stock yielded better than ‘Radana’ trees composed of Caucasian pear seedling and ‘Pyrodwarf’ interstock. ‘Clapp’s Favourite’ in all combinations had significantly heavier fruits. The highest crop efficiency index had ‘Radana’ on quince with ’Doyenne du Comice’ intermediate stock.
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Passos, J. L., R. M. S. A. Meira, and L. C. A. Barbosa. "Foliar anatomy of the species Lantana camara and L. radula (Verbenaceae)." Planta Daninha 27, no. 4 (2009): 689–700. http://dx.doi.org/10.1590/s0100-83582009000400007.

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The species Lantana camara, commonly used as ornamental, has spread worldwide becoming one of the world's most important weeds. To develop new methods of control of this plant, it is essential to distinguish it from other species of the same genus, and this is usually accomplished through taxonomic studies of fertile samples. Considering the similarity between L. camara and L. radula, and the consequent difficulty in distinguishing one from the other when only sterile samples are available, this work aimed to investigate the use of the anatomical characteristics of the leaves of both species as tools for supporting correct classification. The leaves of L. camara and L. radula were anatomically examined by light microscopy and scanning electron microscopy. The major differences were observed in the petiole, which presented secretory idioblasts in L. camara. Secretory idioblasts were observed in the leaf blades of L. camara and Crystalliferou idioblasts were found in L. radula. Glandular and nonglandular trichomes as well as the abaxial surface are different in each species. Such results can support the strategies aiming at the control of L. camara without interfering with L. radula.
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Mamontov, Yuriy S., Michael S. Ignatov, Dmitry V. Vasilenko, Andrei A. Legalov, and Evgeny E. Perkovsky. "Hepatics from Rovno amber (Ukraine). 11. Radula oblongifolia and R. tikhomirovae sp. nov." Ecologica Montenegrina 72 (April 17, 2024): 189–99. http://dx.doi.org/10.37828/em.2024.72.18.

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A study of Rovno amber has revealed two fossil leafy liverwort species of the genus Radula (Radulaceae, Marchantiophyta) that are new to the late Eocene flora of Rovno amber. One of these species, R. oblongifolia, was described previously from Eocene Baltic and Bitterfeld amber, whereas the other species, R. tikhomirovae, is described here as new. Radula tikhomirovae differs from R. oblongifolia and two other Eocene species of that genus, R. sphaerocarpoides and R. baltica, by the presence of microphyllous branches and by the shape of its leaf lobules.
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Roebuck, C. J., S. J. Siebert, J. M. Berner, and J. Marcelo-Silva. "The Influence of Serpentine Soil on the Early Development of a Non-Serpentine African Thistle, Berkheya radula (Harv.) De Wild." Plants 11, no. 18 (September 9, 2022): 2360. http://dx.doi.org/10.3390/plants11182360.

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Serpentine soils are rich in heavy metals and poor in nutrients, limiting plant species’ performance and survival. Nevertheless, specificities of such limitations as well as adaptability features required for thriving in serpentine environments are barely known. The Barberton Greenstone Belt in South Africa is an example of an area containing serpentine soil with adapted vegetation. In this study, a pot experiment was performed to compare development features (i.e., germination rates, leaf count, leaf length, biomass and photosynthetic capacity) during the early development of the non-serpentine species Berkheya radula, a genus consisting of known metal hyperaccumulators from serpentine areas in South Africa. B. radula was grown in serpentine soils taken from the Barberton region. B. radula leaves had heavy metals in concentrations that confirmed the species as a phytoextractor. There were trends for enhanced productivity and photosynthesis in the serpentine treatments compared to the control. Leaf count, leaf length, electron transport efficiency (ψEo/(1 − ψEo), density of reaction centers and PIABS,total were significantly and positively correlated with at least one of the heavy metals in the leaves. Germination rates were positively influenced by K, whereas biomass and the density of reaction centers were negatively affected by Ca and P, and only Ca, respectively. The heavy metals Zn, Ni and Co were positively correlated with each other, whereas they were negatively correlated with the macronutrients K, Ca and P. The latter correlated positively with each other, confirming higher fertility of the control soil. Our study suggests that B. radula exhibits metallophyte characteristics (i.e., preadapted), despite not naturally occurring on metal-enriched soil, and this provides evidence that the potential for bioaccumulation and phytoremediation is shared between serpentine and non-serpentine species in this genus.
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Pócs, Tamás. "Contribution to the bryoflora of Australia, V. Radula tonitrua sp. nov. from Queensland." Telopea 24 (May 5, 2021): 189–201. http://dx.doi.org/10.7751/telopea14918.

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Study of two recognised geographic lineages within Radula novae-hollandiae sens. lat. have resulted in the detection of morphological differences between individuals from the Queensland Wet Tropics, and those from New South Wales. Individuals from the Wet Tropics have perianths that are shorter at maturity (1.6–2.0 v. 3.8–4.4 mm), leaf lobes that usually bear numerous marginal gemmae, and leaf-lobules that are smaller and more quadrate. The morphological differences, particularly in perianth length, were not fully appreciated previously and provide evidence supporting the recognition of the Queensland Wet Tropics lineage as a distinct and new species, Radula tonitrua, which is here described. The degree of phylogenetic divergence and fixed molecular difference between R. tonitrua and R. novae-hollandiae, are comparable with the separation observed between R. ocellata and R. pulchella, another species pair exhibiting the same geographic disjunction.
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Kodym, Andrea, Ian Clarke, Cristina Aponte, Shane Turner, Eric Bunn, and John Delpratt. "Large-scale micropropagation of the Australian key species Gahnia radula (Cyperaceae) and its return to revegetation sites." Australian Journal of Botany 62, no. 5 (2014): 417. http://dx.doi.org/10.1071/bt14091.

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We report on the successful propagation of the sedge Gahnia radula (R.Br.) Benth. from seed by using plant tissue culture, and its successful establishment in the field. This keystone species, although common along parts of the eastern coast of Australia, is currently not available for revegetation because of a lack of efficient propagation methods, leading to the use of substitute species in many restoration programs. Even though seed quality is a common problem for G. radula, one population bearing filled seed was located in the near-east of Melbourne and after harvest of fruit in December 2011, seeds were successfully germinated in vitro after removal of the pericarp. Overnight soaking in sterile 10% (v/v) smoke water before culturing enhanced in vitro germination from 29.2% to 66.7%. In vitro-grown seedlings were then used as starting material for tissue-culture propagation via shoot culture. A micropropagation rate of about six new plantlets per cycle was achieved within 5–6 weeks with liquid half-strength Murashige–Skoog medium and a pulse treatment with 10 µM 6-benzylaminopurine (BAP) and 2 µM naphthalene acetic acid (NAA). Plants rooted after receiving a pulse treatment with 5 µM kinetin and were successfully acclimatised into potting mix and were ready for field planting after 5–6 months. Tube stock was planted into two field sites with minimal weed control. Survival was 98% in both cases 1 month after planting and 54% and 74% after the summer. Division of in vitro-derived plants in the nursery was very successful, with 93–96% establishment of divisions. This research highlights the important role of plant tissue culture in conserving biodiversity of native flora.
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Rezende, Denise V., and José C. Dianese. "Revisão taxonômica de algumas espécies de Ravenelia em leguminosas do Cerrado brasileiro." Fitopatologia Brasileira 28, no. 1 (January 2003): 27–36. http://dx.doi.org/10.1590/s0100-41582003000100004.

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Oito espécies de Ravenelia descritas anteriormente foram revisadas e acrescentadas ilustrações inéditas das características morfológicas de alguns desses fungos causadores de ferrugem em Leguminosae. As espécies de Ravenelia estudadas foram: Ravenelia bezerrae sobre Enterolobium ellipticum ; R. densifera sobre Senna silvestris; R. dieteliana sobre Calliandra dysantha. var. dysantha; R. geminipora sobre Platymenia reticulata; R. lonchocarpi sobre Lonchocarpus campestris; R. mimosae-sensitivae sobre Mimosa radula var. imbricata; R. pileolarioides sobre Caesalpinia pyramydales e R. santos-costae, sobre Calliandra dysantha.
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Assis, Marta Camargo de. "ALSTROEMERIACEAE NO ESTADO DO RIO DE JANEIRO." Rodriguésia 55, no. 85 (July 2004): 5–15. http://dx.doi.org/10.1590/2175-78602004558501.

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RESUMO Neste trabalho são apresentadas as espécies de Alstroemeriaceae do estado do Rio de Janeiro, Brasil. A família e representada na área pelo gênero Alstroemeria, incluindo cinco espécies: A. caryophyllaea Jacq., A. cunha Vell., A. foliosa Mart. ex Schult. & Schult. f., A. isabelleana Herb., A. radula Dusén e pelo gênero Bomarea incluindo apenas a especie B. edulis (Tussac) Herb. Novas sinonimizações, chaves de identificação, descriçãoao das espécies, ilustrações e comentários são aqui apresentados.
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Dissertations / Theses on the topic "Radula (plantes)"

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Thuillier, Simon. "Étude du mode d’action de la radulanine A, une molécule phytotoxique d’origine naturelle." Electronic Thesis or Diss., Sorbonne université, 2023. http://www.theses.fr/2023SORUS318.

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La radulanine A est une substance naturelle identifiée dans les années 1970 chez des hépatiques du genre Radula et dont l’activité phytotoxique a été récemment mise en évidence. L’objectif de la thèse a été de déterminer le mode d’action de cette substance en utilisant Arabidopsis thaliana comme plante modèle. La mise au point d’une voie de synthèse totale en 5 étapes a permis de synthétiser la radulanine A ainsi que des analogues structuraux en quantité suffisante pour réaliser l’étude biologique. Cette nouvelle voie de synthèse utilise une étape finale d’extension de cycle par photochimie en flux à partir d’un chromène désigné « Radula chromène » dans le manuscrit. Ce composé, ainsi que les autres intermédiaires de cette voie de synthèse, sont des molécules naturelles également présentes chez des hépatiques du genre Radula. Parmi ces analogues, le Radula chromène et la tylimanthine B présentent une phytotoxicité similaire à celle de la radulanine A. En revanche, l’analogue O-méthylé du Radula chromène apparait biologiquement inactif, suggérant que le groupement phénolique est indispensable à l’activité phytotoxique des composés étudiés. L’étude de la phytotoxicité des analogues a ainsi permis d’apporter les premiers éléments reliant structure et activité phytotoxique de la radulanine A et de ses analogues naturels. L’impact de ces différentes molécules sur le fonctionnement de la chaîne de transfert d'électron photosynthétique a été finement étudié via des analyses de fluorescence des chlorophylles. Les données obtenues indiquent que les analogues bioactifs inhibent le rendement de la chaîne de transfert d’électron photosynthétique au sein des plantules traités. Les analyses de thermoluminescence menées sur des photosystèmes II isolés indiquent que la radulanine A et le Radula chromène, mais pas l’analogue chromène O-méthylé, inhibent la fonctionnalité du site QB du photosystème II. Cette étude établit donc une corrélation forte entre inhibition de la phase photochimique de la photosynthèse et phytotoxicité de la Radulanine A et de ses analogues bioactifs. La Radulanine A est ainsi la première molécule à structure dihydrooxépine identifiée comme inhibitrice de ce site. En parallèle, l’effet du Radula chromène sur le métabolisme de plantules d’Arabidopsis a été étudié via une approche métabolomique par GC-MS. Les quatre-vingt-dix-huit métabolites détectés et quantifiés dans les plantules au cours de cette étude sont majoritairement issus du métabolisme primaire (sucres, acides aminés, acides organiques, purines). Quatre-vingt-deux métabolites présentent une différence significative d’abondance après traitement par le Radula chromène. Les variations sont rapides, et essentiellement observées en réponse à la plus forte dose (400 µM) appliquée. L’application du Radula chromène induit une réduction de la quantité de la plupart des métabolites détectés, suggérant un impact sur la globalité du métabolisme primaire des plantules. Des expériences préliminaires ont été réalisées pour établir un lien fonctionnel entre l’effet du Radula chromène sur le métabolisme et sa phytotoxicité. Dans l'ensemble, l’élaboration d’une nouvelle synthèse totale courte de la radulanine A a permis de définir le potentiel d’inhibition de la photosynthèse par la radulanine A et certains analogues structuraux. Des études supplémentaires ont permis d’identifier la radulanine A, ainsi que le Radula chromène, comme inhibiteurs du photosystème II au sein du site QB. L’étude de l’impact du Radula chromène sur le métabolome primaire des plantules suggère que l’inhibition de la photosynthèse ne serait pas le seul mode d’action responsable de la phytotoxicité. Des analyses complémentaires à l’étude métabolomique telle qu’une étude lipidomique permettrait la vérification de cette hypothèse
Radulanin A is a natural substance identified in the 1970s in liverworts of the Radula genus, and recently shown to have phytotoxic activity. The purpose of this PhD project was to determine the mode of action of this substance, using Arabidopsis thaliana as a model plant. The development of a 5-step total synthesis route made it possible to synthesize radulanine A and structural analogues in sufficient quantity to carry out biological studies. This new synthetic route employs a final cycle-extension step by flow photochemistry starting from a chromene designated "Radula chromene" in the manuscript. This compound, as well as the other intermediates of this synthetic route, are natural molecules also found in liverworts of the Radula genus. Of these analogues, Radula chromene and tylimanthin B exhibit phytotoxicity similar to that of radulanin A. In contrast, the O-methylated analog of Radula chromene appeared biologically inactive, suggesting that the phenolic group is essential for the phytotoxic activity of the studied compounds. The study of the phytotoxicity of the analogues thus provided the first evidence linking the structure and phytotoxic activity of radulanine A and its natural analogues. The impact of these different molecules on the photosynthetic electron transfer chain was studied in detail using chlorophyll fluorescence analyses. The data obtained indicate that the bioactive analogues inhibit the performance of the photosynthetic electron transfer chain in treated seedlings. Thermoluminescence analyses carried out on isolated photosystems II indicate that radulanin A and Radula chromene, but not the O-methylated chromene analog, inhibit the activity of the QB site of photosystem II. This study therefore establishes a strong correlation between inhibition of the photochemical phase of photosynthesis and phytotoxicity of radulanine A and its bioactive analogues. Radulanin A is thus the first molecule with a dihydrooxepin structure to be identified as an inhibitor of this site. In parallel, the effect of Radula chromene on the metabolism of Arabidopsis seedlings was studied using a GC-MS metabolomics approach. The ninety-eight metabolites detected and quantified in the seedlings during this study were mainly derived from primary metabolism (sugars, amino acids, organic acids, purines). Eighty-two metabolites showed a significant difference in abundance after treatment with Radula chromene. Variations are fast, and mainly observed in response to the highest dose (400 µM) applied. The application of Radula chromene induced a reduction in the quantity of most of the metabolites detected, suggesting an impact on the overall primary metabolism of the seedlings. Preliminary experiments were carried out to establish a functional link between the effect of Radula chromene on metabolism and its phytotoxicity. Overall, the development of a new short total synthesis of radulanin A defined the potential for inhibition of photosynthesis by radulanin A and certain structural analogues. Further studies identified radulanine A and Radula chromene as photosystem II inhibitors within the QB site. Investigation of the impact of Radula chromene on the seedling primary metabolome suggests that inhibition of photosynthesis may not be the only mode of action responsible for phytotoxicity. Complementary analyses to the metabolomic study, such as a lipidomic study, would enable this hypothesis to be verified
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Ortiz, Mauricio, Sabine Reffert, Trifon Trifonov, Andreas Quirrenbach, David S. Mitchell, Grzegorz Nowak, Esther Buenzli, et al. "Precise radial velocities of giant stars." EDP SCIENCES S A, 2016. http://hdl.handle.net/10150/622444.

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Context. For over 12 yr, we have carried out a precise radial velocity (RV) survey of a sample of 373 G- and K-giant stars using the Hamilton Echelle Spectrograph at the Lick Observatory. There are, among others, a number of multiple planetary systems in our sample as well as several planetary candidates in stellar binaries. Aims. We aim at detecting and characterizing substellar and stellar companions to the giant star HD 59686 A (HR 2877, HIP 36616). Methods. We obtained high-precision RV measurements of the star HD 59686 A. By fitting a Keplerian model to the periodic changes in the RVs, we can assess the nature of companions in the system. To distinguish between RV variations that are due to non-radial pulsation or stellar spots, we used infrared RVs taken with the CRIRES spectrograph at the Very Large Telescope. Additionally, to characterize the system in more detail, we obtained high-resolution images with LMIRCam at the Large Binocular Telescope. Results. We report the probable discovery of a giant planet with a mass of m(p) sin i = 6.92(-0.24)(+0.18) M-Jup orbiting at a(p) = 1.0860(-0.0007)(+0.0006) aufrom the giant star HD 59686 A. In addition to the planetary signal, we discovered an eccentric (e(B) = 0.729(-0.003)(+0.004)) binary companionwith a mass of m(B) sin i = 0.5296(-0.0008)(+0.0011) M-circle dot orbiting at a close separation from the giant primary with a semi-major axis of a(B) = 13.56(-0.14)(+0.18) au. Conclusions. The existence of the planet HD 59686 Ab in a tight eccentric binary system severely challenges standard giant planet formation theories and requires substantial improvements to such theories in tight binaries. Otherwise, alternative planet formation scenarios such as second-generation planets or dynamical interactions in an early phase of the system's lifetime need to be seriously considered to better understand the origin of this enigmatic planet.
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Brucalassi, Anna. "Search for extra-solar planets with high precision radial velocity curves." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-173637.

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This Ph.D. Thesis has as general subject the study of extrasolar planets using the radial velocity technique from both, instrumental and observative, points of view. Two main parts compose the work: the upgrade of the spectrograph FOCES, a high resolution spectrograph that will be installed next year at the Wendelstein Observatory, and the search of giant planets around stars in the open cluster Messier-67 (M67).
Die vorliegende Dissertation behandelt die Suche von extra-solaren Planeten mit der Radialgeschwindigkeits Methode und zwar sowohl in Bezug auf die dafür notwendige Instrumentierung als auch auf die Beobachtung. Die Arbeit ist in zwei Teile gegliedert. Im ersten Teil werden die vorgenommenen Verbesserungen des hochauflösenden Spektrographen FOCES beschrieben, der im kommenden Jahr am Wendelstein Observatorium installiert werden wird. Der zweite Teil handelt von der Suche nach Gasplaneten im offenen Sternhaufen M67.
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Haywood, Raphaëlle D. "Hide and seek : radial-velocity searches for planets around active stars." Thesis, University of St Andrews, 2015. http://hdl.handle.net/10023/7798.

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The detection of low-mass extra-solar planets through radial-velocity searches is currently limited by the intrinsic magnetic activity of the host stars. The correlated noise that arises from their natural radial-velocity variability can easily mimic or conceal the orbital signals of super-Earth and Earth-mass extra-solar planets. I developed an intuitive and robust data analysis framework in which the activity-induced variations are modelled with a Gaussian process that has the frequency structure of the photometric variations of the star, thus allowing me to determine precise and reliable planetary masses. I applied this technique to three recently discovered planetary systems: CoRoT-7, Kepler-78 and Kepler-10. I determined the masses of the transiting super-Earth CoRoT-7b and the small Neptune CoRoT-7c to be 4.73 ± 0.95 M⊕ and 13.56 ± 1.08 M⊕, respectively. The density of CoRoT-7b is 6.61 ± 1.72 g.cm⁻³, which is compatible with a rocky composition. I carried out Bayesian model selection to assess the nature of a previously identified signal at 9 days, and found that it is best interpreted as stellar activity. Despite the high levels of activity of its host star, I determined the mass of the Earth-sized planet Kepler-78b to be 1.76 ± 0.18 M⊕. With a density of 6.2(+1.8:-1.4) g.cm⁻³, it is also a rocky planet. I found the masses of Kepler-10b and Kepler-10c to be 3.31 ± 0.32 M⊕ and 16.25 ± 3.66 M⊕, respectively. Their densities, of 6.4(+1.1:-0.7) g.cm⁻³ and 8.1 ± 1.8 g.cm⁻³, imply that they are both of rocky composition – even the 2 Earth-radius planet Kepler-10c! In parallel, I deepened our understanding of the physical origin of stellar radial-velocity variability through the study of the Sun, which is the only star whose surface can be imaged at high resolution. I found that the full-disc magnetic flux is an excellent proxy for activity-induced radial-velocity variations; this result may become key to breaking the activity barrier in coming years. I also found that in the case of CoRoT-7, the suppression of convective blueshift leads to radial-velocity variations with an rms of 1.82 m.s⁻¹, while the modulation induced by the presence of dark spots on the rotating stellar disc has an rms of 0.46 m.s⁻¹. For the Sun, I found these contributions to be 2.22 m.s⁻¹ and 0.14 m.s⁻¹, respectively. These results suggest that for slowly rotating stars, the suppression of convective blueshift is the dominant contributor to the activity-modulated radial-velocity signal, rather than the rotational Doppler shift of the flux blocked by starspots.
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Borgniet, Simon. "Recherche et caractérisation de planètes géantes autour d'étoiles massives et/ou jeunes de la Séquence Principale : modélisation de l'activité d'étoiles de type solaire et impact sur la détection de planètes de masse terrestre." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAY063/document.

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La recherche des exoplanètes traverse aujourd'hui une période décisive. D'un côté, notre connaissance des planètes géantes gazeuses s'est considérablement développée, et l'objectif de la recherche est maintenant de caractériser leurs propriétés physiques et de mieux comprendre leurs mécanismes de formation et d'évolution. D'un autre côté, la précision et la stabilité des instruments ont atteint un niveau qui rend techniquement possible la détection de planètes telluriques situées dans la zone habitable de leur étoile. Cependant, les perturbations du signal dues à l'étoile elle-même constituent un obstacle important à cette avancée. Mon travail de thèse se situe à la rencontre de ces problématiques. Il a consisté d'une part en l'analyse de deux relevés de vitesses radiales visant des étoiles relativement exotiques pour la recherche d'exoplanètes: les étoiles naines de type AF massives. Ce travail a donné lieu à la première caractérisation de la population de planètes géantes autour de ces étoiles et a montré que les mécanismes de migration planétaire étaient au moins partiellement inhibés autour de ces étoiles par rapport aux étoiles de type FGKM. Dans un second temps, j'ai conduit les observations et l'analyse des premiers résultats de deux grands relevés de vitesses radiales débutés pendant ma thèse et visant à détecter des planètes géantes en orbite autour d'étoiles jeunes et proches. Ces étoiles jeunes sont les seules sources pour lesquelles une exploration complète des planètes géantes à toutes les séparations devient possible, par combinaison des techniques de vitesses radiales et de l'imagerie. Cette combinaison permettra de tester de manière unique les modèles de formation et d'évolution planétaire. Les résultats provisoires de ces relevés indiquent une absence de planètes géantes à très courte séparation (Jupiters chauds) autour de nos cibles. Un autre résultat intéressant est la découverte d'une binaire spectroscopique eccentrique au centre d'un système planétaire imagé à grande séparation. Pour compléter cette approche observationnelle et mieux évaluer la détectabilité des exoplanètes semblables à la Terre, j'ai étalonné et caractérisé un modèle entièrement paramétré de l'activité d'une étoile semblable au Soleil et de son impact sur les vitesses radiales. Je l'ai dans un premier temps étalonné en comparant ses résultats à ceux obtenus à partir d'observations des zones actives du Soleil, puis je l'ai utilisé pour caractériser l'impact de l'inclinaison de l'étoile sur le signal induit par l'activité. Ce modèle paramétré ouvre de très nombreuses possibilités, étant en effet potentiellement adaptable à des types d'étoiles et d'activité différents. Il permettrait ainsi de caractériser les perturbations en vitesses radiales attendues pour chaque cas testé, et donc à la fois de déterminer quelles étoiles et quels types d'activité sont les plus favorables pour la détection de planètes de masse terrestre dans la zone habitable. En explorant ces trois problématiques en apparence très diverses mais complémentaires, j'y ai retrouvé un motif commun, celui de l'importance des étoiles elles-mêmes et de la physique stellaire pour la recherche d'exoplanètes
The search for exoplanets has reached a decisive moment. On the one hand, our knowledge of giant gaseous planets has significantly developed, and the aim of the research is now to characterize their physical properties and to better understand the formation and evolution processes. On the other hand, the instrumental precision and stability have reached a level that makes it technically possible to detect telluric planets in the habitable zone of their host star. However, the signal alterations induced by the star itself definitely challenge this breakthrough. My PhD stands at the crossroads of these problems. It consisted first in the analysis of two radial velocity surveys dedicated to stars somewhat exotic to exoplanet searches: the massive AF dwarf stars. This work has led to the first characterization of the giant planet population found around these stars and has showed that the planetary migration mechanisms were at least partially inhibited around these stars compared to FGKM stars. I then made the observations and the first analysis of two radial velocity surveys dedicated to the search for giant planets around young, nearby stars. Young stars are the only sources for which a full exploration of the giant planets at all separations can be reached, through the combination of radial velocities techniques and direct imaging. Such a combination will allow to test uniquely the planetary formation and evolution processes. The first results of these surveys show an absence of giant planets at very short separations (Hot Jupiters) around our targets. Another interesting result is the detection of an eccentric spectroscopic binary at the center of a planetary system imaged at a wide separation. To complete this observational approach and better estimate the detectability of Earth-like planets, I calibrated and characterized a fully parameterized model of the activity pattern of a Sun-like star and its impact on the radial velocities. I first calibrated it by comparing it to the results obtained with observations of the solar active structures, and then characterized the impact of stellar inclination on the activity-induced signal. Such a fully parameterized model is potentially adaptable to different types of stars and of activity and would thus allow to characterize the expected radial velocity jitter for each tested case, and then allow both to determine which types of stars and of activity patterns are the most favorable for detecting Earth-like planets in the habitable zone. While investigating these three seemingly different but complementary topics, I found that they shared a basic feature, namely the importance of the stars themselves and of stellar physics in exoplanet searches
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Schoeffel, Janaina. "Simetria radial de soluções positivas de sistemas elípticos cooperativos." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/45/45132/tde-21052012-213355/.

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Neste trabalho estudamos a questão de simetria de soluções positivas de equações e sistemas de equações diferenciais parciais. Descrevemos em detalhe a demonstração de dois resultados sobre simetria radial, um para equações em domínios limitados e outro para sistemas de equações no espaço todo. Ambas as demonstrações baseiam-se no método dos moving planes. Em seguida aplicamos um dos resultados mencionados acima para a equação de Choquard.
In this work we study the question of symmetry for positive solutions of equations and systems of partial differential equations. We describe in detail the proof of two results on radial symmetry, one for equations in bounded domains and the other for systems of equations in the whole space. Both proofs are based on the method of moving planes. We apply one of the results mentioned above for the Choquards equation.
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Tan, Xianyu, and 谭先瑜. "Characterizing the orbital and dynamical state of extrasolar multiple-planet systems with radial velocity measurements." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50162792.

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Extrasolar planetary surveys have discovered about 780 extrasolar planets and more than 100 multiple planetary systems to date, with the largest fraction of them being confirmed by the radial velocity detection method. Multiple planetary systems, especially those contain pairs of planets in mean-motion resonances, are particularly interesting because their current orbital architectures provide constraints for orbital evolution of planetary systems. Precisely determining the orbital and dynamical state of multiple planetary systems with radial velocity measurements is important. New results from an analysis of radial velocity data of the HD 82943 planetary system based on 10 years of measurements obtained with the Keck telescope is presented in this thesis. Previous studies have shown that the HD 82943 system has two planets that are likely in 2:1 MMR, with the orbital periods about 220 and 440 days (Lee et al. 2006). However, alternative fits that are qualitatively different have also been suggested, with the two planets in 1:1 resonance or the addition of a third planet possibly in a Laplace 4:2:1 resonance with the other two (Goździewski & Konacki 2006; Beaugé et al. 2008). Here based on the X^2 minimization method combined with parameter grid search, the orbital parameters and dynamical states of the qualitatively different types of fits have been investigated. The results support the coplanar 2:1 MMR configuration for this system and fits of the 1:1 resonance and the 3-planet Laplace resonance are ruled out according to X^2 statistic and dynamical instability. The inclination of the HD 82943 system is well constrained at about 20°C. The system contains two planets with masses of about 4.64 MJ and 4.66 MJ and orbital periods of about 219 and 442 days for the inner and outer planet, respectively. The best fit is dynamically stable with two resonance angles θ 1 = λ1 - 2λ2 + ϖ1 and θ 2 = λ1 - 2λ2 + ϖ 2 librating around 0°. Based on the best fit, the origin of the 2:1 MMR of the HD 82943 planetary system has been explored by N-body simulations with forced inward migration of the outer planet. This research has demonstrated the importance of dynamical fitting for multiple planetary systems with radial velocity measurements. It also fulfills the cases of planetary systems in mean-motion resonances such that more generic understanding of the orbital evolution of planetary systems can be obtained.
published_or_final_version
Earth Sciences
Master
Master of Philosophy
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Hollis, M. D. J. "Characterisation of extrasolar planets : applications to radial velocity cataloguing and atmospheric radiative transfer." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1427268/.

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This thesis concerns the cataloguing and characterisation of extrasolar planets, an important topic given its potential to inform theories of planet formation and evolution, and its relevance for future studies defining and assessing the habitability of other worlds. The first aspect of the study is the calculation of orbits, using radial velocity measurements coupled with Bayesian and Markov chain Monte Carlo methods, to produce a catalogue of orbital elements for a sizeable sample of planets. This constitutes a self-consistent, uniformly-derived catalogue, useful for statistical planetary population and formation studies, to be contrasted with other databases of planetary parameters, which are in general compilations of measurements from different sources and using various techniques. The orbital elements determine important star-on-planet forcings (for example ultra-violet irradiation, which has significant impacts on planetary (photo)chemistry and dynamics), and this study also looks at characterising planets explicitly in terms of their atmospheres. A 1D radiative transfer model for planetary transmission spectroscopy has been produced, and made freely-available for use by the community. This method is particularly useful since it allows the retrieval of first-order abundances of trace atmospheric molecules, which in turn can be used to estimate parameters such as the C/O ratio, potentially providing further constraints on planetary formation processes. The code in question has been validated by comparison to models in the literature, and applied to several real planetary atmospheres. It has also been extended by incorporating a method to estimate the opacity due to scattering particles in clouds and haze layers. If present in an atmosphere such phenomena can lead to the persistence of various parameter degeneracies, and limit the extent to which inferences can be drawn from spectra (leading to potentially order-of-magnitude errors in estimates of molecular abundances). Future extensions to this work could include the development of an automated inversion framework, utilising joint Bayesian/Markov chain Monte Carlo techniques to explore the parameter space of all relevant atmospheric quantities in order to retrieve a complete solution that is consistent with observations.
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Ritzer, Jason Andreas. "The Topography, Gravity, and Tectonics of the Terrestrial Planets." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1278603504.

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Sainsbury-Martinez, Felix. "Flows, instabilities, and magnetism in stars and planets." Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/32072.

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Flows, instabilities, and magnetism play significant roles in the internal and atmospheric dynamics of objects ranging from the smallest exoplanets to the largest stars. These phenomena are governed by the equations of magnetohydrodynamics (MHD), which link the flows and magnetic fields, and from which the operational parameters and growth rates of instabilities can be recovered. Here we present an overview of interesting phenomena (such as the internal dynamics of stellar and planetary objects, as well as instabilities which might operate within these environs), as well as computational techniques by which these phenomena might both be understood and analysed (through both ‘simplifications’ of the MHD equations and different numerical/computational approaches). We first present an investigation into the Heat-Flux-Driven Buoyancy Instability (HBI) within stellar and planetary atmospheres, considering both the parameter space it might operate within as well as its non-linear effects during said operation. We find that whilst the HBI may be able to play a role in Solar, stellar and planetary atmospheres, it is likely to be quite limited in scope, only operating within small regions. However, its dramatic consequences for heat transport in the non-linearly evolved state, and the prospects that it may operate outside the narrow regimes that our analytical analysis suggested, suggest that it may merit further study. This is followed with a discussion of a method by which the surface flows of exoplanets might be measured: The Rossiter-Mclaughlin Effect at Secondary Eclipse (RMse). We formulate the effect, showing that the formalism is identical to the traditional Rossiter-Mclaughlin effect, albeit in a different frame (a planet transiting a star becomes a star transiting a planet), and consider its observational implications: the effect should be observable for the brightest planet hosting stars using upcoming 40m-class telescopes (i.e.E-ELT). We finish with a series of 3D anelastic simulations of fully convective stars, designed to investigate how the internal flows are affected by varying stellar parameters, as well as a possible link between residual entropy and differential rotation contours, and a method by which this link can be used (via the thermal wind equation - TWE) to extrapolate the internal rotation. We find a clear transition between ‘solar-like’ and ‘anti-solar’ internal dynamics, characterised in the meridional circulation, differential rotation, residual entropy, and angular momentum flux profiles. Furthermore we find that, whilst the alignment between residual entropy and differential rotation contours is somewhat varied, the resultant extrapolation, via the TWE, produces a generally good fit to the differential rotation contours, suggesting a general robustness to the theory.
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Books on the topic "Radula (plantes)"

1

Haywood, Raphaëlle D. Radial-velocity Searches for Planets Around Active Stars. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-41273-3.

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Pizzolato, Thompson Demetrio. Vascular system of the male and female florets of Raddia brasiliensis (Poaceae:Bambusoideae:Olyreae). Washington, D.C: Smithsonian Institution Press, 1990.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Haywood, Raphaëlle D. Radial-Velocity Searches for Planets Around Active Stars. Springer London, Limited, 2016.

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Haywood, Raphaëlle D. Radial-velocity Searches for Planets Around Active Stars. Springer, 2018.

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Haywood, Raphaëlle D. Radial-velocity Searches for Planets Around Active Stars. Springer, 2016.

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Book chapters on the topic "Radula (plantes)"

1

Latham, David W., and Nader Haghighipour. "Radial-Velocity Planets." In Encyclopedia of Astrobiology, 2107–13. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44185-5_1839.

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Latham, David W. "Radial-Velocity Planets." In Encyclopedia of Astrobiology, 1400–1404. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-11274-4_1839.

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Latham, David W., and Nader Haghighipour. "Radial-Velocity Planets." In Encyclopedia of Astrobiology, 1–8. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-27833-4_1839-2.

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Latham, David W., and Nader Haghighipour. "Radial-Velocity Planets." In Encyclopedia of Astrobiology, 1–9. Berlin, Heidelberg: Springer Berlin Heidelberg, 2022. http://dx.doi.org/10.1007/978-3-642-27833-4_1839-3.

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Latham, David W., and Nader Haghighipour. "Radial-Velocity Planets." In Encyclopedia of Astrobiology, 2560–68. Berlin, Heidelberg: Springer Berlin Heidelberg, 2023. http://dx.doi.org/10.1007/978-3-662-65093-6_1839.

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McMillan, R. S., and P. H. Smith. "A Radial Velocity Search for Extrasolar Planets." In Astrophysics and Space Science Library, 91–92. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2959-3_13.

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Mazeh, T. "Radial Velocity Detections of Extra-Solar Planets." In Astronomical Time Series, 133–44. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-015-8941-3_11.

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Aloni, Roni. "Ray Differentiation: The Radial Pathways." In Vascular Differentiation and Plant Hormones, 245–50. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-53202-4_15.

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Hatzes, Artie P., William D. Cochran, and Michael Endl. "The Detection of Extrasolar Planets Using Precise Stellar Radial Velocities." In Planets in Binary Star Systems, 51–76. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-8687-7_3.

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Santerne, Alexandre. "Populations of Extrasolar Giant Planets from Transit and Radial Velocity Surveys." In Handbook of Exoplanets, 1–23. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-30648-3_154-1.

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Conference papers on the topic "Radula (plantes)"

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Epple, Philipp, Mihai Miclea, Harald Schmidt, Antonio Delgado, and Hans Russwurm. "High Pressure Fan Design for Biogas Plants." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-12852.

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High pressure fans for thermal power generation stations, especially biogas plants, usually operate in a spiral casing at high pressures of about p = 12.000–15.000 Pa and low flow rates of around Q = 100–600 m3/s. The motor drive has a constant speed of 3.000 l/min. This corresponds to specific speeds of nq = 3–6 min−1, which is already beyond the conventional range of single stage radial machines. Nowadays these fans for biogas plants usually operate at higher flow rates than specified or are multiple stage radial fans. Therefore a new class of radial impellers has been developed. These single stage impellers have a unique high pressure at a low flow rate operating point. In this work several impellers of this new class have been designed and validated with a commercial Navier-Stokes solver (ANSYS CFX). The design process is described in detail. It is based on a new extended analytical and numerical design method. It is shown that the prescribed unusual operating point can be achieved with single stage radial impellers. An in detail flow analysis is given showing the fundamental flow physics of these impellers.
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KALJEVIĆ, Andrijana, Goran NIKČEVIĆ, and Dragutin GARDAŠEVIĆ. "TRAINING FOR SAFE WORK IN HIGH VOLTAGE PLANTS." In Bezbednost i zdravlje na radu sa zdravstveno-medicinskog i tehničko-bezbednosnog aspekta, ekologije i zaštite od požara. Udruženje za promociju bezbednosti i zdravlјa na radu, ekologije, zaštite od požara, fizičko tehničko obezbeđenje, zaštite od jonizujućih zračenja profesionalno izloženih lica, 2024. http://dx.doi.org/10.46793/hse24.095k.

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As a strategic issue, a general rule and a common concern of the employer and the employee, the management of safety and health at work in EPCG AD Nikšić and CEDIS, through the implementation of an integrated management system (IMS), of which the ISO 45001:2018 standard is an integral part, was adopted as a principle based on to risk management, in a way to ensure the effectiveness of safety and health at workplaces, prevention of work-related injuries and health impairments. Works in HV plants belong to the category of jobs with special working conditions and increased risk. Therefore, they prescribe strictly controlled conditions of movement, residence and work, so special attention is paid to the training of employees who service these facilities for safe work. Training and proficiency testing is carried out theoretically and practically, at the employee's place of work, in accordance with the assessment of the level of risk, dangers and hazards for the workplace to which the employee is assigned. Training for safe work is carried out in three phases, through a general, specialist and special program. For the purposes of practical training, employees are assigned a practical training instructor, a person who has professional qualifications, competences and experience in certain jobs. After successfully conducted theoretical and practical training, and with the aim of independent performance of work, the authorized Commission for the performance of professional work in the field of safety and health at work performs a qualification check for safe work at the employee's place of work, after which it issues a Certificate of qualification for safe work. Since the main cause of injuries at work is ignorance of the basic rules and principles of work protection in the technological process, adequately implemented training for safe work is of the greatest importance for reducing the level of risk to the lowest possible extent.
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Hussain, T., and O. Kayser. "Identification of transcription factors from Radula marginata TAYLOR." In 67th International Congress and Annual Meeting of the Society for Medicinal Plant and Natural Product Research (GA) in cooperation with the French Society of Pharmacognosy AFERP. © Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-3399661.

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Clegg, Jon, Patrick E. Rodi, and Andrew Meade. "Waverider Crossflow Model Validation for Radial and Length Variations Between Osculating Planes." In 23rd AIAA International Space Planes and Hypersonic Systems and Technologies Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2020. http://dx.doi.org/10.2514/6.2020-2405.

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"Radial plant growth – Cellular coordination during growth in two dimensions." In Plant Genetics, Genomics, Bioinformatics, and Biotechnology. Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 2019. http://dx.doi.org/10.18699/plantgen2019-166.

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Lamorte, Nicolas, and Peretz Friedmann. "Hypersonic Aeroelastic Stability Boundary Computations Using Radial Basis Functions for Mesh Deformation." In 18th AIAA/3AF International Space Planes and Hypersonic Systems and Technologies Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2012. http://dx.doi.org/10.2514/6.2012-5943.

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Cerri, G., L. Battisti, and G. Soraperra. "Non-Conventional Turbines for Hydrogen Fueled Power Plants." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38324.

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A survey was carried out on CO2 & NOx emission-free hydrogen-fuelled power cycles, pinpointing characteristic points of steam turbine expansions. Innovative aspects arose for turbine design owing to unexplored steam thermodynamic states, severe operating conditions and lifetime issues. A Ljungstro¨m-type radial-flow turbine design was explored for such an application, investigating stress, cooling and thrust-balancing aspects. Massive cooling was recognized as a primary need to ensure safe turbine operation. To take technological and thermodynamic issues into account, an integrated procedure was set up for preliminary design. The final design is amply discussed.
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Wang, Xing, Xiaomin Liu, and Chuhua Zhang. "Performance Analysis of Organic Rankine Cycle With Preliminary Design of Radial Turbo Expander for Binary-Cycle Geothermal Plants." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95933.

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In order to produce less emission of greenhouse gas, many studies have been done on the binary-cycle geothermal power plant to obtain the better performance. The radial turbo expander plays an important role in the performance of Organic Rankine Cycle (ORC) for binary-cycle geothermal plants. However, few studies have investigated the effect of parameters of radial turbo expander on the performance of ORC. In this paper, a new thermodynamic model of ORC coupled with the preliminary design of radial turbo expanders is developed. The effects of geothermal water temperature on the ORC performance parameters such as power output and thermal efficiency are investigated by using the proposed thermodynamic model. The variation of radial turbo expanders’ parameters such as specific rotational speed with geothermal water temperature is revealed. In the present study, the more reasonable efficiency of radial turbo expanders by using the preliminary design is adapted to analysis the performance of ORC, and more accuracy reference about the effect of geothermal source on the parameters of radial turbo expanders is obtained.
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Terrien, Ryan C., Chad F. Bender, Suvrath Mahadevan, Lawrence W. Ramsey, Fred R. Hearty, and William D. Vacca. "Simulations of a near-infrared precision radial velocity spectrograph for finding planets around M dwarfs." In SPIE Astronomical Telescopes + Instrumentation, edited by Ian S. McLean, Suzanne K. Ramsay, and Hideki Takami. SPIE, 2013. http://dx.doi.org/10.1117/12.926478.

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Borman, Rohmat Indra, Farli Rossi, Dedy Alamsyah, Rini Nuraini, Yessi Jusman, and Fauziyah. "Classification of Medicinal Wild Plants Using Radial Basis Function Neural Network with Least Mean Square." In 2022 2nd International Conference on Electronic and Electrical Engineering and Intelligent System (ICE3IS). IEEE, 2022. http://dx.doi.org/10.1109/ice3is56585.2022.10010072.

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Reports on the topic "Radula (plantes)"

1

Rincón Romero, Mayerli Katherine. Valoración de enfermería para la persona en el contexto familiar basada en los patrones funcionales de salud de M. Gordon. Ediciones Universidad Cooperativa de Colombia, December 2022. http://dx.doi.org/10.16925/gcgp.63.

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La presente guía práctica brinda recomendaciones para orientar la fase inicial del proceso enfermero: la valoración, con una estructuración de la entrevista de enfermería a la persona en el contexto familiar. La valoración establece un proceso planificado y sistemático de recopilación de datos subjetivos y objetivos, con la aplicación de instrumentos validados (escalas, test, entre otros), que conduce posteriormente a la interpretación de la información del estado de salud del sujeto de cuidado para la toma de decisiones en la elaboración de planes de cuidados con enfoque hacia la respuesta humana integral y global ante una necesidad del sujeto de cuidado. La Valoración por Patrones Funcionales de Marjory Gordon aporta una serie de primacías al proceso: pueden ser manejadas independientemente del modelo enfermero que se sigue, se integran de forma apropiada al ámbito de la atención primaria de salud y permiten estructurar y ordenar los datos de la valoración, funcionan para cualquier sujeto de cuidado: individuo a lo largo del ciclo vital, familia o comunidad, en situaciones de salud o enfermedad, y facilitan el tránsito a la siguiente fase de diagnóstico enfermero al contrastar con el origen de la clasificación por dominios de la NANDA. El objetivo de esta guía radica en ofrecer a los estudiantes del programa de enfermería conocimientos de los procesos y las herramientas que pueden ser utilizadas para la valoración de enfermería, dirigido a la familia y a la persona, fundamental en el contexto de la atención primaria.
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Levy, Avraham, Clifford Weil, and Wojtek Pawlowski. Enhancing the Rate of Meiotic Crossing-Over for Plant Breeding. United States Department of Agriculture, January 2009. http://dx.doi.org/10.32747/2009.7696532.bard.

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Meiotic recombination contributes to the generation of biodiversity as well as to genome stability, ensuring the proper segregation of homo logs during meiosis. It is also an essential step in the process of plant breeding. It generates the diversity needed by the breeder for selection of novel varieties. In this project, we have collaborated towards the goals to identify and characterize key genes involved in meiotic recombination. In addition we have shown how some of these genes can be used, through loss of function, or through overexpression, to enhance homologous recombination in Arabidopsis and in maize. Our main achievements can be summarized as follows: 1- To establish a collection of mutants, in Arabidopsis and in maize for candidate genes. In Arabidopsis, insertion mutants were isolated in the following genes: AtMSHI, AtMSH4, AtMSH5, AtMLH3, AtPHSl, and mutants in the Mre11/Rad50/Nbs1 complex. In maize, the TILLING system was established and enabled to isolate mutants in candidate genes, such as Rad2l-4a, Sgo2, and Aml. In addition, we generated phs 1 mutant alleles as well as mutants in the Mre11/Rad50/Nbs1 complex. No mus8l mutants have been found thus far. 2- We showed that mutants in AtMLH3 have decreased rates of crossover, suggesting that overexpression of these genes may enhance crossover. Mutants in AtMSHlhad no effect and mutants in AtMSH4 and 5 showed sterility. Overexpression of these genes might also enhance crossover. The effect of other mutations on crossovers in maize is still being investigated. 3- We showed that overexpression of AtMLH1, RecG and RuvC under a meioticspecific promoter enhances meiotic crossover in Arabidopsis. The effect of PHSloverexpression on crossover is expected to be determined soon. 4- New tools have been developed and perfected to study the recombination genes effect on meiotic crossovers. This includes antibodies, cDNAs and fusion proteins.
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Gupta, Shikhar, Mehtab Ahmed, Sayema ., Azam Haseen, and Saif Quaiser. Relevance of Preoperative Vessel Mapping and Early Postoperative Ultrasonography in Predicting AV Fistula Failure in Chronic Kidney Disease Patients. Science Repository, February 2024. http://dx.doi.org/10.31487/j.rdi.2023.02.02.

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Introduction: The increasing prevalence of chronic kidney disease (CKD), coupled with advancements in the diagnosis and treatment of renal diseases and improvements in life expectancy, has led to a greater number of patients requiring hemodialysis. The preferred method of vascular access for hemodialysis is AV fistula formation; however, it is associated with a high rate of failure. In our prospective study, we focused on 40 CKD patients planned for initiation of maintenance hemodialysis. Methods: We employed preoperative ultrasound mapping to assess cephalic vein diameter, compressibility, and colour flow, as well as radial and brachial artery diameter, peak systolic velocity, and intimal wall calcification. Postoperatively, ultrasound examinations were conducted on day 7 and at 6 weeks to evaluate fistula blood volume and detect any complications. Results: A significant association between fistula failure and cephalic vein diameter, brachial artery diameter, intimal vessel wall calcification, and comorbid conditions like diabetes mellitus was observed. Furthermore, blood flow at day 7 was notably lower in the failure group compared to those with a functioning fistula and any fistula with blood flow <154 ml/min on day 7 may be predictive of early fistula failure. Conclusion: Preoperative vessel mapping and early postoperative ultrasonography is indispensable for patients who require AV fistula formation for hemodialysis and provide valuable information for selecting suitable vessels for successful fistula creation and enable early intervention to salvage a failing fistula after the surgery. By utilizing these, healthcare professionals can make informed decisions and take necessary steps to optimize the outcomes of AV fistula formation in patients undergoing hemodialysis.
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Campos, Nicolás, and Manuel Urquidi. Políticas activas de mercado laboral en Bolivia: impacto del Programa de Apoyo al Empleo II. Inter-American Development Bank, March 2024. http://dx.doi.org/10.18235/0012861.

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Las Políticas Activas de Mercado laboral son un conjunto de instrumentos de política pública que buscan fomentar la integración laboral, especialmente la de grupos con bajos niveles de empleabilidad e ingresos. La evidencia señala que estas políticas han sido efectivas en fomentar el acceso a empleos de calidad en Latinoamérica y el Caribe (Urzúa & Puentes, 2010; Card et al., 2010, 2018; Escudero, 2018; Escudero et al., 2019; Carranza & Mckenzie, 2023). El Programa de Apoyo al Empleo (PAE II), implementado por el Servicio Plurinacional de Empleo (SPE) bajo el Ministerio de Trabajo, Empleo y Previsión Social (MTEPS) y apoyado por el Banco Interamericano de Desarrollo (BID) desde 2010, forma parte de este tipo de políticas. Analizamos el impacto del PAE II sobre el empleo, empleo en unidades económicas formales e ingresos mensuales en Bolivia. Optamos por un enfoque cuasi-experimental debido a la naturaleza no aleatoria de la asignación de participantes al programa: el acceso al programa es universal y la selección de candidatos desde las listas elaboradas por el SPE es discrecional por parte de las empresas. Para identificar el impacto causal del programa, combinamos datos de encuestas a beneficiarios y no beneficiarios, con una estrategia empírica que recurre a extensiones de los modelos de diferencias en diferencias. El uso de esta estrategia de estimación radica en que para ver si el programa realmente tiene un impacto sobre ingresos y empleo, no podemos simplemente comparar los ingresos o el empleo de quienes participaron en el PAE II con los que no lo hicieron, ya que puede haber muchas otras diferencias entre estos dos grupos que afecten los resultados. Aquí es donde necesitamos un contrafactual: una estimación de la historia laboral que habrían seguido los participantes del PAE en caso de que no hubieran participado en el programa. El modelo de diferencias en diferencias, bajo ciertos supuestos, nos permite estimar el contrafactual, y así poder identificar el impacto causal que tuvo el programa sobre quienes participaron en él. Encontramos que la participación en el PAE II que ofrece intermediación laboral, subsidio directo y capacitación en planta durante tres meses aumenta la probabilidad de obtener un empleo en 14 pp. siendo este efecto más fuerte en mujeres (14,8 pp.) en comparación con los hombres (14 pp.). En términos de empleo en unidades económicas formales, la tasa de empleo aumenta 14,9 pp. siendo mayor en mujeres (14,9 pp) que en hombres (14,3 pp.). Los ingresos mensuales de los beneficiarios activos aumentarán entre un 9,5 %. Este efecto es mayor en mujeres, con un aumento en los ingresos de un 11,7 % en comparación con un 8,1 % en hombres. El impacto del PAE II es especialmente fuerte en el corto plazo y decreciente en el tiempo, no obstante, tiene un impacto positivo y significativo tanto para empleo como ingresos hasta 24 meses después de haber iniciado el programa. Los resultados indican que el PAE II ha logrado reducir efectivamente las barreras de acceso al mercado laboral formal en Bolivia y ha mejorado la trayectoria de ingresos de los beneficiarios. Esto se manifiesta en un aumento en la probabilidad de conseguir empleo en unidades económicas formales y una mejora en los ingresos mensuales, lo que refleja un incremento en la productividad de los beneficiarios activos. Dicho aumento en productividad se alinea con el componente de capacitación en planta del programa. Estos hallazgos son coherentes con evaluaciones anteriores del programa que también sugieren impactos positivos en los beneficiarios, especialmente en empleo (Novella & Valencia, 2022). Nuestros hallazgos están en línea con la literatura que señala que los programas de capacitación bien diseñados, focalizados y con incentivos adecuados tienden a generar mejoras sostenibles en los resultados laborales, especialmente en grupos que tradicionalmente tienen restringido el acceso al mercado laboral.
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