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Journal articles on the topic 'Gradient champ'

Author: Grafiati

Published: 4 June 2021

Last updated: 12 February 2022

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1

Boczar, J., A. Dorobczynski, and J. Miakotoi. "Modèle de transfert et de diffusion de masse dans un écoulement, en présence de gradients de vitesse et de gradients du coefficient de diffusion turbulente." Revue des sciences de l'eau 5, no. 3 (2005): 353–79. http://dx.doi.org/10.7202/705136ar.

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Le travail présente un modèle mathématique conceptuel de transfert et de diffusion de masse destiné à l'étude des migrations d'effluents en rivière. Ce modèle prend en compte l'existence d'écoulements cisaillés ainsi que la présence de gradients de diffusion turbulente. Il permet de calculer les champs de concentrations et les valeurs moyennes de concentration à travers toute section transversale de l'écoulement. La localisation et la taille relative du rejet sont respectées. L'influence des rives sur les processus de dispersion est prise en considération.Pour quantifier l'influence des berges

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Park, J., H. Lühr, and M. Noja. "Three-dimensional morphology of equatorial plasma bubbles deduced from measurements onboard CHAMP." Annales Geophysicae 33, no. 1 (2015): 129–35. http://dx.doi.org/10.5194/angeo-33-129-2015.

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Abstract. Total electron content (TEC) between Low-Earth-Orbit (LEO) satellites and the Global Navigation Satellite System (GNSS) satellites can be used to constrain the three-dimensional morphology of equatorial plasma bubbles (EPBs). In this study we investigate TEC measured onboard the Challenging Minisatellite Payload (CHAMP) from 2001 to 2005. We only use TEC data obtained when CHAMP passed through EPBs: that is, when in situ plasma density measurements at CHAMP altitude also show EPB signatures. The observed TEC gradient along the CHAMP track is strongest when the corresponding GNSS sate

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Bondé, Loyapin, Oumarou Ouédraogo, François Kagembèga, and Joseph Issaka Boussim. "Impact des gradients topographique et anthropique sur la diversité des formations ligneuses soudaniennes." BOIS & FORETS DES TROPIQUES 318, no. 318 (2013): 15. http://dx.doi.org/10.19182/bft2013.318.a20514.

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Le paysage soudanien est en pleine mutation avec une conversion progressive des formations soudaniennes en formations sahéliennes. Dans cette étude, menée sur les formations ligneuses soudaniennes, l'objectif était d'évaluer, d'une part, les effets isolés du mode d'utilisation des terres et de la position topographique et, d'autre part, celui de leurs interactions sur la diversité floristique des formations végétales. Pour ce faire, des relevés phytosociologiques de superficies variables ont été réalisés dans trois types d'unités d'utilisation des terres (forêt classée, jachère, champ) suivant

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4

Taylor, P. T., K. I. Kis, and G. Wittmann. "Interpretation of CHAMP magnetic anomaly data over the Pannonian Basin region using lower altitude horizontal gradient data." Acta Geodaetica et Geophysica 48, no. 3 (2013): 275–80. http://dx.doi.org/10.1007/s40328-013-0026-4.

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Didon, N., S. Agnel, J. Castellon, et al. "Distribution du champ électrique sous haute tension continue et gradient de température dans le diélectrique des câbles extrudés." Journal of Electrostatics 64, no. 7-9 (2006): 456–60. http://dx.doi.org/10.1016/j.elstat.2005.10.032.

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Delpierre, Cyrille, Raphaële Castagné, Thierry Lang, and Michelle Kelly-Irving. "Environnement social, incorporation biologique et inégalités sociales de santé." médecine/sciences 34, no. 8-9 (2018): 740–44. http://dx.doi.org/10.1051/medsci/20183408023.

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Le gradient social de santé renvoie au fait que plus on s’élève dans la hiérarchie sociale meilleur est l’état de santé. La compréhension de la construction du gradient constitue un enjeu majeur en épidémiologie sociale. Une approche originale consiste à s’intéresser à la façon dont les différentes expositions associées à l’environnement social (chimiques, physiques, comportementales, psychosociales, etc.) s’expriment in fine biologiquement pour influencer positivement ou négativement la santé, renvoyant au concept d’incorporation biologique. Des données issues des modèles animaux et de l’épid

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K.-Seguin, Maurice, and Jean Crépault. "Étude géographique d’un champ de palses à Poste-de-la-Baleine, Nouveau-Québec." Géographie physique et Quaternaire 33, no. 3-4 (2011): 327–37. http://dx.doi.org/10.7202/1000368ar.

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Le champ de palses de Poste-de-la-Baleine est situé au 55°12’55’’N et au 77°43’50’’O à une altitude de 107 m. L’aire d’étude comprend une trentaine de palses réparties sur une superficie d’environ 0,8 km2. Seulement 13 palses répondent aux exigences (formes et dimensions) de l’étude qui a porté sur la stratigraphie, la granulométrie, la géomorphologie et la géophysique. Une coupe stratigraphique généralisée comprend de la base au sommet une épaisseur indéterminée d’argile silteuse interstratifiée de minces couches de glace. Un lit de sable de 60 cm d’épaisseur contenant des blocs granitiques a

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Park, J., H. Lühr, B. G. Fejer, and K. W. Min. "Duskside F-region dynamo currents: its relationship with prereversal enhancement of vertical plasma drift." Annales Geophysicae 28, no. 11 (2010): 2097–101. http://dx.doi.org/10.5194/angeo-28-2097-2010.

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Abstract. From magnetic field observations by CHAMP we estimate F-region dynamo current densities near the sunset terminator during solar maximum years from 2001 to 2002. The dynamo currents are compared with the pre-reversal enhancement (PRE) of vertical plasma drift as observed by ROCSAT-1. The seasonal-longitudinal variation of PRE can be largely related to the F-region dynamo current density, with the correlation coefficient reaching 0.74. The correlation can be further improved if we consider a zonal gradient of the E-region Pedersen conductivity, which also depends on season and longitud

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Zhang, Qiang, Tai-Jie Zhang, Wah Soon Chow, Xin Xie, Yuan-Jun Chen, and Chang-Lian Peng. "Photosynthetic characteristics and light energy conversions under different light environments in five tree species occupying dominant status at different stages of subtropical forest succession." Functional Plant Biology 42, no. 7 (2015): 609. http://dx.doi.org/10.1071/fp14355.

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In order to reveal the mechanism of succession in subtropical forest along a light gradient, we investigated photosynthetic physiological responses to three light environments in five tree species including a pioneer species Pinus massoniana Lamb., two mid-successional species Schima superba Gardn. et Champ. and Castanopsis fissa (Champ. ex Benth.) Rehd. et Wils., and two late-successional species Cryptocarya concinna Hance. and Acmena acuminatissima (BI.) Merr et Perry) that were selected from Dinghu Mountain subtropical forest, South China. Results showed that, among the three kinds of speci

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Smith, A. R. A., C. D. Beggan, S. Macmillan, and K. A. Whaler. "Climatology of the Auroral Electrojets Derived From the Along-Track Gradient of Magnetic Field Intensity Measured by POGO, Magsat, CHAMP, and Swarm." Space Weather 15, no. 10 (2017): 1257–69. http://dx.doi.org/10.1002/2017sw001675.

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Reubelt, T., G. Austen, and E. W. Grafarend. "Space Gravity Spectroscopy - determination of the Earth’s gravitational field by means of Newton interpolated LEO ephemeris Case studies on dynamic (CHAMP Rapid Science Orbit) and kinematic orbits." Advances in Geosciences 1 (July 11, 2003): 127–35. http://dx.doi.org/10.5194/adgeo-1-127-2003.

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Abstract. An algorithm for the (kinematic) orbit analysis of a Low Earth Orbiting (LEO) GPS tracked satellite to determine the spherical harmonic coefficients of the terrestrial gravitational field is presented. A contribution to existing long wavelength gravity field models is expected since the kinematic orbit of a LEO satellite can nowadays be determined with very high accuracy in the range of a few centimeters. To demonstrate the applicability of the proposed method, first results from the analysis of real CHAMP Rapid Science (dynamic) Orbits (RSO) and kinematic orbits are illustrated. In

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Губенко, Владимир, Vladimir Gubenko, Иван Кириллович, and Ivan Kirillovich. "Modulation of sporadic E layers by small-scale atmospheric waves in Earth’s high-latitude ionosphere." Solnechno-Zemnaya Fizika 5, no. 3 (2019): 116–29. http://dx.doi.org/10.12737/szf-53201912.

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We have used radio occultation measurements of the satellite CHAMP (Challenging Minisatellite Payload) to examine sporadic E layers (altitudes 90–130 km) in Earth’s high-latitude ionosphere. We have developed a new method for determining characteristics of internal atmospheric waves based on the use of inclined sporadic E layers of Earth’s ionosphere as a detector. The method relies on the fact that an internal wave propagating through the initially horizontal sporadic E layer causes the plasma density gradient to rotate in the direction of the wave vector, which leads to the fact that the lay

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Губенко, Владимир, Vladimir Gubenko, Иван Кириллович, and Ivan Kirillovich. "Modulation of sporadic E layers by small-scale atmospheric waves in Earth’s high-latitude ionosphere." Solar-Terrestrial Physics 5, no. 3 (2019): 98–108. http://dx.doi.org/10.12737/stp-53201912.

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We have used radio occultation measurements of the satellite CHAMP (Challenging Minisatellite Payload) to examine sporadic E layers (altitudes 90–130 km) in Earth’s high-latitude ionosphere. We have developed a new method for determining characteristics of internal atmospheric waves based on the use of inclined sporadic E layers of Earth’s ionosphere as a detector. The method relies on the fact that an internal wave propagating through the initially horizontal sporadic E layer causes the plasma density gradient to rotate in the direction of the wave vector, which leads to the fact that the lay

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Chen, Weishi, Lili Zhou, Yong Qiao, Jianzhong Qi, Guocheng Fu, and Xinhua Xia. "Quality Evaluation of Ilex asprella Based on Simultaneous Determination of Five Bioactive Components, Chlorogenic Acid, Luteoloside, Quercitrin, Quercetin, and Kaempferol, Using UPLC–Q-TOF MS Study." Journal of AOAC INTERNATIONAL 102, no. 5 (2019): 1414–22. http://dx.doi.org/10.1093/jaoac/102.5.1414.

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Abstract Background: Ilex asprella (Hook. Et Arn.) Champ. Ex Benth. is one of the representative medicinal plants that naturally grows in South China. It serves as a major component of herbal tea as an aid for sore throat, toothache, and acne, and it is a folk medicine for treating upper respiratory tract inflammation resulting from fever, infectious hepatitis, and enteritis. Objective: To evaluate the quality of Ilex asprella, the bioactive components were identified comprehensively using quadruple time-of-flight (Q-TOF) MS, and the HPLC method for quality evaluation was established for the f

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Chornaya, O. A., and T. P. Yegorova. "Gravity field of Sarmatia according to satellite data (model EIGEN-6S2) and its interpretation." Geofizicheskiy Zhurnal 43, no. 3 (2021): 47–63. http://dx.doi.org/10.24028/gzh.v43i3.236380.

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The paper presents a brief overview of satellite observations of the CHAMP, GRACE and GOCE missions to study the Earth’s global gravity field, and the used mathematical apparatus in the form of an expansion of the geopotential in spherical harmonics. The application of satellite data in various fields of Earth Sciences is considered. As a basic global model of the Earth’s gravity field based on satellite data we used the EIGEN-6S2 model [Rudenko et al, 2014] that combines satellite mission data GRACE and GOCE, and also uses satellite data of LAGEOUS laser ranging. On its basis, the gravity fie

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16

Canet, D. "Les gradients de champ radio-fréquence (gradients B1) en RMN." Journal de Chimie Physique 92 (1995): 1893–904. http://dx.doi.org/10.1051/jcp/1995921893.

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17

Shen, Xiuwei, Jianshe Ma, Xianqin Wang, Congcong Wen, and Meiling Zhang. "Toxicokinetics of 11 Gelsemium Alkaloids in Rats by UPLC-MS/MS." BioMed Research International 2020 (July 15, 2020): 1–13. http://dx.doi.org/10.1155/2020/8247270.

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Gelsemium elegans (Gardn. & Champ.) Benth. is a plant belonging to the genus Gelsemium (family Gelsemiaceae), and its main components are alkaloids. It is a Chinese traditional medicinal plant and notoriously known as a highly toxic medicine. However, a method has not yet been found for the simultaneous detection of 11 Gelsemium alkaloids in rat plasma, and the toxicokinetics of 11 Gelsemium alkaloids after intravenous administration has not been reported. In this work, we have developed a sensitive and rapid method of ultraperformance liquid chromatography/tandem mass spectrometry (UPLC-M

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18

Franconi, J. M. "4126 Les gradients de champs magnetiques." Journal de Radiologie 85, no. 9 (2004): 1204. http://dx.doi.org/10.1016/s0221-0363(04)76658-5.

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19

Sanz, Fernando. "Trajectoires non-oscillantes des champs de vecteurs gradients." Comptes Rendus de l'Académie des Sciences - Series I - Mathematics 325, no. 4 (1997): 429–32. http://dx.doi.org/10.1016/s0764-4442(97)85630-3.

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20

Abdul Jabbar, Noor Maan, and Ban Ahmed Mitras. "Modified Chimp Optimization Algorithm Based On Classical Conjugate Gradient Methods." Journal of Physics: Conference Series 1963, no. 1 (2021): 012027. http://dx.doi.org/10.1088/1742-6596/1963/1/012027.

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21

Humbert, F., E. Mischler, and D. Canet. "Mesures globale et localisée du coefficient d'autodiffusion par gradients de champ radiofréquence." Journal de Chimie Physique 92 (1995): 1905–8. http://dx.doi.org/10.1051/jcp/1995921905.

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22

Sokolovskiy, S., Y.-H. Kuo, and W. Wang. "Evaluation of a Linear Phase Observation Operator with CHAMP Radio Occultation Data and High-Resolution Regional Analysis." Monthly Weather Review 133, no. 10 (2005): 3053–59. http://dx.doi.org/10.1175/mwr3006.1.

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Abstract In this study a nonlocal, linear observation operator for assimilating radio occultation data is evaluated. The operator consists of modeling the excess phase, that is, integrating the refractivity along straight lines tangent to rays, below a certain height. The corresponding observable is the excess phase integrated through the Abel-retrieved refractivity, along the same lines, below the same height. The operator allows very simple implementation (computationally efficient) while accurately accounting for the horizontal refractivity gradients. This is due to significant cancellation

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23

Balasis, G., I. A. Daglis, I. R. Mann, et al. "Multi-satellite study of the excitation of Pc3 and Pc4-5 ULF waves and their penetration across the plasmapause during the 2003 Halloween superstorm." Annales Geophysicae 33, no. 10 (2015): 1237–52. http://dx.doi.org/10.5194/angeo-33-1237-2015.

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Abstract. We use multi-satellite and ground-based magnetic data to investigate the concurrent characteristics of Pc3 (22–100 mHz) and Pc4-5 (1–22 mHz) ultra-low-frequency (ULF) waves on the 31 October 2003 during the Halloween magnetic superstorm. ULF waves are seen in the Earth's magnetosphere, topside ionosphere, and Earth's surface, enabling an examination of their propagation characteristics. We employ a time–frequency analysis technique and examine data from when the Cluster and CHAMP spacecraft were in good local time (LT) conjunction near the dayside noon–midnight meridian. We find clea

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Masunari, Setuko. "Distribuição e abundância dos caranguejos Uca Leach (Crustacea, Decapoda, Ocypodidae) na Baía de Guaratuba, Paraná, Brasil." Revista Brasileira de Zoologia 23, no. 4 (2006): 901–14. http://dx.doi.org/10.1590/s0101-81752006000400001.

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Um estudo sobre distribuição espacial e abundância dos chama-marés Uca Leach, 1814 foi realizado na Baía de Guaratuba, Estado do Paraná. Foram coletados chama-marés de dez biótopos ao longo de um gradiente de salinidade de zero a 32 dentro da Baía de Guaratuba. Foram obtidas sete espécies, entre as quais, Uca mordax (Smith, 1870) que foi registrada somente em biótopos inundados por águas de baixas salinidades (de zero a 16). As demais espécies mostraram tolerância a uma ampla variação de salinidade, mas Uca maracoani (Latreille, 1802-1803) e Uca leptodactyla Rathbun, 1898 predominaram em águas

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Descroix, L., J. F. Nouvelot, J. Estrada, and T. Lebel. "Complémentarités et convergences de méthodes de régionalisation des précipitations : application à une région endoréique du Nord-Mexique." Revue des sciences de l'eau 14, no. 3 (2005): 281–305. http://dx.doi.org/10.7202/705421ar.

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La connaissance des champs pluviométriques annuels est importante dans les zones arides et semi-arides où la gestion de l'eau est un exercice permanent d'aménagement de la pénurie, comme cela est le cas au Nord du Mexique. On se propose de montrer ici qu'une meilleure connaissance des disponibilités en eau peut s'appuyer sur la détermination de régions pluviométriquement homogènes à partir de diverses méthodes complémentaires ou convergentes. Pour définir des régions homogènes, on part de la répartition des stations par rapport à la régression pluviométrie/altitude. Des analyses factorielles e

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Pais, Mara Patrícia, and Elenice Mouro Varanda. "Variation in plant defenses of Didymopanax vinosum (Cham. & Schltdl.) Seem. (Apiaceae) across a vegetation gradient in a Brazilian cerrado." Acta Botanica Brasilica 17, no. 3 (2003): 395–403. http://dx.doi.org/10.1590/s0102-33062003000300007.

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Cerrado vegetation is composed of a mosaic of vegetation types, from campo sujo, dominated by herbs; campo cerrado and cerrado sensu stricto, with shrubby vegetation; to cerradão, with trees forming a denser forest. This physiognomic mosaic is related to differences in the water availability in the soil. Cerrado plants are considered physically and chemically well defended against herbivores, but there are no studies showing how plants allocate investment to various types of defensive mechanisms in different habitat physiognomies. The defensive mechanisms and the nutritional traits of a cerrad

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Vijverberg, Jacobus, Eshete Dejen, Abebe Getahun, and Leopold A. J. Nagelkerke. "The composition of fish communities of nine Ethiopian lakes along a north-south gradient: threats and possible solutions." Animal Biology 62, no. 3 (2012): 315–35. http://dx.doi.org/10.1163/157075611x618246.

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Fish populations of nine Ethiopian freshwater lakes were quantitatively sampled with a standardized protocol, using multi-mesh gill nets. In total, 27 species were identified, but only 14 species were common. Based on the common species, the fish communities showed large differences in their species composition, except for Lake Abaya and Lake Chamo which were similar. Most fish species were observed in only one or two lakes. Compared with the information reported in literature the present study generally underestimated the species richness. The empirical model of Amarasinghe and Welcomme (2002

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Barraza Sandoval, José Enrique, Verónica Esperanza Melara, and Angelo Picardo. "Poliquetos y otra fauna macrobentónica asociada de la franja intermareal rocosa de Mizata, La Libertad, El Salvador." Realidad y Reflexión 54, no. 54 (2021): 252–65. http://dx.doi.org/10.5377/ryr.v54i54.12084.

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Las franjas rocosas intermareales son hábitats importantes para conservar la biodiversidad en regiones costeras, pero los estudios científicos son escasos, particularmente en el litoral de El Salvador. El presente estudio determinó distribución, abundancia de poliquetos y otra macrofauna bentónica de la zona rocosa intermareal de Mizata, durante febrero, abril y junio (2017); estableciendo tres transectos horizontales y perpendiculares a la línea litoral con 0.5 m de altura en gradiente vertical, se incluyeron entre cuatro y cinco cuadrantes (25 cm2) durante marea baja, recolectando fauna inte

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Cucurull, L., J. C. Derber, R. Treadon, and R. J. Purser. "Preliminary Impact Studies Using Global Positioning System Radio Occultation Profiles at NCEP." Monthly Weather Review 136, no. 6 (2008): 1865–77. http://dx.doi.org/10.1175/2007mwr2260.1.

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Abstract Following the successful launch of the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) satellites in April 2006, NCEP’s Environmental Modeling Center (EMC) is planning to use the COSMIC data in its next-generation Global Data Assimilation System. In preparation for the assimilation of GPS radio occultation (RO) data from COSMIC and other missions, NCEP/EMC has developed the infrastructure necessary to use profiles of refractivity and bending angle in an operational framework. In both forward operators, horizontal gradients of refractivity have been negl

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Jasso-Flores, Isela, Leopoldo Galicia, Felipe García-Oliva, and Angelina Martínez-Yrízar. "Are vegetation–soil systems drivers of ecosystem carbon contents along an elevational gradient in a highland temperate forest?" Canadian Journal of Forest Research 49, no. 3 (2019): 296–304. http://dx.doi.org/10.1139/cjfr-2018-0245.

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Vegetation–soil systems differentially influence the ecosystem processes related to the carbon cycle, particularly when one tree species is dominant over wide geographic regions that are undergoing climate change. The objective of this study was to quantify the stocks of ecosystem carbon in three vegetation–soil systems along a highland elevational gradient in central Mexico. The vegetation–soil systems, from lower to higher elevation, were dominated by Alnus jorullensis Kunth, Abies religiosa (Kunth) Schltdl. & Cham., and Pinus hartwegii Lindl., respectively. Above- and below-ground tree

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Seguin, Maurice K., and Michel Allard. "Le Pergélisol et les processus Thermokarstiques de la région de la rivière Nastapoca, Nouveau-Québec." Géographie physique et Quaternaire 38, no. 1 (2007): 11–25. http://dx.doi.org/10.7202/032532ar.

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RÉSUMÉ L'embouchure de la rivière Nastapoca, sur la côte est de la mer d'Hudson, est située dans la zone de pergélisol discontinu, en domaine de toundra arbustive. La morphologie cryogène y varie selon les types de dépôts quaternaires dans lesquels le pergélisol s'est installé. Les limons argileux de la mer de Tyrrell se caractérisent par des champs de buttes cryogènes entrecoupées de mares de thermokarst et de vallons dissymétriques. Parsemé d'ostioles et animé de mouvements de solifluxion et de glissements superficiels, le mollisol évolue de façon très dynamique. La densité croissante des la

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Dahik, Marín, Arias, Crespo, Weber, and Palomeque. "Comparison of Natural Regeneration in Natural Grassland and Pine Plantations across an Elevational Gradient in the Páramo Ecosystem of Southern Ecuador." Forests 10, no. 9 (2019): 745. http://dx.doi.org/10.3390/f10090745.

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During the 1980s, reforestation programs using exotic species (Pinus spp.) were established in the páramo ecosystem of Ecuador. The aims of this study were: (1) to compare the natural regeneration between pine plantations (Pi) and natural grassland (NG) across an elevational gradient and (2) to identify the attributes of Pi and soil properties that were influencing herbaceous and woody plant composition and their plant cover. In total, six independent Pinus patula (Schltdl. & Cham. plantations (two per each elevation) were selected and distributed in an elevational range (3200–3400, 3400–3

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Ortiz-Bibian, Marisol A., Dante Castellanos-Acuña, Mariela Gómez-Romero, Roberto Lindig-Cisneros, Miguel Ángel Silva-Farías, and Cuauhtémoc Sáenz-Romero. "VARIACIÓN ENTRE POBLACIONES DE Abies religiosa (H.B.K.) Schl. et Cham A LO LARGO DE UN GRADIENTE ALTITUDINAL. I. CAPACIDAD GERMINATIVA DE LA SEMILLA." Revista Fitotecnia Mexicana 42, no. 3 (2019): 301–8. http://dx.doi.org/10.35196/rfm.2019.3.301-308.

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Abies religiosa (HBK) Schl. & Cham. (oyamel) es una conífera nativa de México. El bosque de oyamel que se ubica en la frontera del Estado de México y Michoacán funge como refugio de poblaciones de mariposa monarca Danaus plexippus L., pero existe preocupación por el futuro de Abies religiosa en la región debido al cambio de uso de suelo y al cambio climático, pues se espera una reducción de su nicho ecológico. Con la finalidad de generar información que permita planear la cantidad de semilla necesaria a recolectar para realizar programas de reforestación a gran escala en la región de la Re

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Souza, Gustavo Maia, Bruno Depieri Balmant, Hilton Fabrício Vítolo, et al. "Estratégias de utilização de luz e estabilidade do desenvolvimento de plântulas de Cordia superba Cham. (Boraginaceae) crescidas em diferentes ambientes luminosos." Acta Botanica Brasilica 23, no. 2 (2009): 474–85. http://dx.doi.org/10.1590/s0102-33062009000200019.

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A utilização fotossintética da luz é um componente fundamental para a distribuição das espécies ao longo de um gradiente de regeneração de clareiras. O trabalho teve como objetivo avaliar as estratégias de utilização da luz e como isto poderia afetar a estabilidade do desenvolvimento de plantas da espécie Cordia superba crescidas em dois ambientes com irradiações contrastantes. Para tanto, foi conduzido um experimento com plantas de 12 meses de idade de C. superba, uma espécie pioneira arbórea, crescidas a pleno sol e sombreamento de 85%. Foram avaliados aspectos fisiológicos como crescimento

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Doležal, Jiri, Hiroaki Ishii, Tomáš Kyncl, et al. "Climatic factors affecting radial growth of Betula ermanii and Betula platypylla in Kamchatka." Canadian Journal of Forest Research 40, no. 2 (2010): 273–85. http://dx.doi.org/10.1139/x09-179.

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Radial growth responses to climate were studied in two species of birch broadly distributed across Kamchatka Peninsula. Wood cores were obtained in different locations and environments, from upper to lower treelines, and from wet maritime sites at the Pacific to the subcontinental interior of the peninsula. Response functions were calculated using the four longest meteorological records (1920s–2000) in Kamchatka. In Betula ermanii Cham., the dominant species in mountains and maritime woodlands, ring width in high-elevation (500–600 m) trees increased with warm and less rainy June and July and

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Cong, Yu, Mai-He Li, Kai Liu, Yong-Cai Dang, Hu-Dong Han, and Hong S. He. "Decreased Temperature with Increasing Elevation Decreases the End-Season Leaf-to-Wood Reallocation of Resources in Deciduous Betula ermanii Cham. Trees." Forests 10, no. 2 (2019): 166. http://dx.doi.org/10.3390/f10020166.

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Global air temperature has increased and continues to increase, especially in high latitude and high altitude areas, which may affect plant resource physiology and thus plant growth and productivity. The resource remobilization efficiency of plants in response to global warming is, however, still poorly understood. We thus assessed end-season resource remobilization from leaves to woody tissues in deciduous Betula ermanii Cham. trees grown along an elevational gradient ranging from 1700 m to 2187 m a.s.l. on Changbai Mountain, northeastern China. We hypothesized that end-season resource remobi

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Ma, Zaizhong, Ying-Hwa Kuo, F. Martin Ralph, et al. "Assimilation of GPS Radio Occultation Data for an Intense Atmospheric River with the NCEP Regional GSI System." Monthly Weather Review 139, no. 7 (2011): 2170–83. http://dx.doi.org/10.1175/2011mwr3342.1.

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Abstract This paper uses a case study to explore the potential of Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) and Challenging Minisatellite Payload (CHAMP) global positioning system (GPS) radio occultation (RO) satellite data over the eastern Pacific Ocean to improve analyses and mesoscale forecasts of landfalling atmospheric rivers (ARs) along the U.S. West Coast. The case study is from early November 2006 and was a very high-impact event in the Pacific Northwest where it created torrential rainfall and severe flooding. Recent studies have shown that the C

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Cuevas Guzmán, Ramón, Lauro López-Mata, and Edmundo García Moya. "Primer registro de Desmopsis trunciflora (Schlecht. & Cham.) G. E. Schatz (Annonaceae) para el occidente de México y análisis de su población en la Sierra de Manantlán, Jalisco." Acta Botanica Mexicana, no. 58 (January 1, 2002): 7. http://dx.doi.org/10.21829/abm58.2002.887.

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Se registra por primera vez a Desmopsis trunciflora en el estado de Jalisco, donde prospera en un ecotono entre el bosque mesófilo de montaña y el bosque tropical subcaducifolio. Se hace una comparación morfológica con D. mexicana R. E. Fries, una de las especies con las que más se relaciona. Un estudio de la estructura de la población de la especie y de la comunidad donde se desarrolla, nos permitió detectar que de 56 parcelas muestreadas (0.1 ha cada una), a través de un gradiente altitudinal que va de los 550 a los 1,850 m, la especie en cuestión sólo se encontró en 11, entre los 850 y los

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Richard, Pierre J. H. "Le couvert végétal du Québec-Labrador il y a 6000 ans BP : essai." Géographie physique et Quaternaire 49, no. 1 (2007): 117–40. http://dx.doi.org/10.7202/033033ar.

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RÉSUMÉ Une carte du couvert végétal du Québec-Labrador est proposée pour l'époque des 6000 ans BP, à partir des données paléopalynologiques et paléobotaniques. Une Toundra arbustive dense s'interposait entre les mers de Tyrrell ou d'Iberville et les glaces résiduelles qui occupaient alors plus de 100 000 km2 en Ungava (Nunavik) et jusque dans la région de Schefferville. Étroite au sud des glaciers, cette Toundra s'étalait à l'est des glaces sur plus de 400 km jusqu'à la mer du Labrador, au nord du 54° de latitude. La limite des arbres s'établissait donc alors à peu près au centre de l'actuelle

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Tronchère, H., F. Tercé, M. Record, and H. Chap. "Phorbol myristate acetate stimulates [3H]choline incorporation into phosphatidylcholine independently of the ‘de novo’ pathway in Krebs-II ascitic cells: a unique effect of phorbol ester on choline uptake." Biochemical Journal 293, no. 3 (1993): 739–44. http://dx.doi.org/10.1042/bj2930739.

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The effect of phorbol 12-myristate 13-acetate (PMA) on [3H]choline incorporation into phosphatidylcholine (PtdCho) and on the ‘de novo’ pathway of PtdCho synthesis has been investigated, compared with that of oleic acid, in ascitic-strain Krebs-II cells. Both compounds stimulated [3H]choline incorporation into PtdCho, but the PMA-induced incorporation was saturable at concentrations of the agonist around 100 nM, whereas no saturation was noticed with oleic acid up to 1 mM. Chase experiments showed no effect of PMA on the conversion of phosphocholine into CDP-choline. The phorbol ester did not

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LION, JEAN-MARIE, ROBERT MOUSSU, and FERNANDO SANZ. "Champs de vecteurs analytiques et champs de gradients." Ergodic Theory and Dynamical Systems 22, no. 02 (2002). http://dx.doi.org/10.1017/s0143385702000251.

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Motuzaite Matuzeviciute, Giedre, Basira Mir-Makhamad, and Robert N. Spengler. "Interpreting Diachronic Size Variation in Prehistoric Central Asian Cereal Grains." Frontiers in Ecology and Evolution 9 (April 29, 2021). http://dx.doi.org/10.3389/fevo.2021.633634.

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The morphology of ancient cereal grains in Central Asia has been heavily discussed as an indicator of specific genetic variants, which are often linked to cultural factors or distinct routes of dispersal. In this paper, we present the largest currently existing database of barley (n= 631) and wheat (n= 349) measurements from Central Asia, obtained from two different periods at the Chap site (ca. 3,500 to 1,000 BC), located in the Tien Shan Mountains of Kyrgyzstan at 2,000 masl. The site is situated at the highest elevation ecocline for successful cereal cultivation and is, therefore, highly su

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Quiroz Dahik, Carlos, Patricio Crespo, Bernd Stimm, et al. "Impacts of pine plantations on carbon stocks of páramo sites in southern Ecuador." Carbon Balance and Management 16, no. 1 (2021). http://dx.doi.org/10.1186/s13021-021-00168-5.

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Abstract Background Since the 1990’s, afforestation programs in the páramo have been implemented to offset carbon emissions through carbon sequestration, mainly using pine plantations. However, several studies have indicated that after the establishment of pine plantations in grasslands, there is an alteration of carbon pools including a decrease of the soil organic carbon (SOC) pool. The aim of this study is to investigate the impact of the establishment of pine plantations on the carbon stocks in different altitudes of the páramo ecosystem of South Ecuador. Results At seven locations within

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"Social Inequalities in Health in Nonhuman Primates: The Biology of the Gradient. Developments in Primatology: Progress and Prospects. Edited by Carol A. Shively and Mark E. Wilson. Cham (Switzerland): Springer. $159.00 (hardcover); $119.00 (ebook). v + 178 p.; ill.; no index. ISBN: 978-3-319-30870-8 (hc); 978-3-319-30872-2 (eb). 2016." Quarterly Review of Biology 93, no. 3 (2018): 278. http://dx.doi.org/10.1086/699454.

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