Search results for "Planetary Science"
showing 10 items of 4367 documents
Contribution of observed multi frequency spectrum of Alfvén waves to coronal heating
2019
Context. Whilst there are observational indications that transverse magnetohydrodynamic (MHD) waves carry enough energy to maintain the thermal structure of the solar corona, it is not clear whether such energy can be efficiently and effectively converted into heating. Phase-mixing of Alfvén waves is considered a candidate mechanism, as it can develop transverse gradient where magnetic energy can be converted into thermal energy. However, phase-mixing is a process that crucially depends on the amplitude and period of the transverse oscillations, and only recently have we obtained a complete measurement of the power spectrum for transverse oscillations in the corona. Aims. We aim to investig…
Solar Coronal Loops Associated with Small-scale Mixed Polarity Surface Magnetic Fields
2017
L. P. Chitta et. al.
The role of melt composition on aqueous fluid vs. silicate melt partitioning of bromine in magmas
2018
International audience; Volcanogenic halogens, in particular bromine, potentially play an important role in the ozone depletion of the atmosphere. Understanding bromine behaviour in magmas is therefore crucial to properly evaluate the contribution of volcanic eruptions to atmospheric chemistry and their environmental impact. To date, bromine partitioning between silicate melts and the gas phase is very poorly constrained, with the only relevant experimental studies limited to investigation of synthetic melt with silicic compositions. In this study, fluid/melt partitioning experiments were performed using natural silicate glasses with mafic, intermediate and silicic compositions. For each co…
Recensione a Corinne Bonnet (sous la direction de), Noms de dieux. Portraits de divinités antiques Anacharsis Éditions, Toulouse 2021, ISBN 979-10-27…
2022
Review of Noms de dieux. Portraits de divinités antiques, ed. Corinne Bonnet, Anacharsis Éditions, Toulouse 2021
De Piaget a Kohlberg: utilitat i vigència de l'ús de dilemes morals amb l'alumnat universitari
2018
espanolAl cumplirse los 90 anos del nacimiento de Lawrence Kohlberg es de justicia rememorar la importancia de sus aportaciones sobre el desarrollo cognitivo moral de las personas. Pero el progreso de esta teoria no habria sido posible sin los estudios previos de Jean Piaget sobre el proceso de construccion de la moral autonoma en el nino. La obra de ambos autores ha tenido grandes repercusiones pedagogicas en el camino para la construccion de un pensamiento justo y autonomo. Una de las tecnicas utilizadas por Kohlberg para que las personas progresasen en los estadios de desarrollo moral, por el definidos, es la de los dilemas morales. Entendemos que esta tecnica continua siendo valida en l…
The Role of Autophagy in Eye Diseases
2021
Autophagy is a catabolic process that ensures homeostasis in the cells of our organism. It plays a crucial role in protecting eye cells against oxidative damage and external stress factors. Ocular pathologies of high incidence, such as age-related macular degeneration, cataracts, glaucoma, and diabetic retinopathy are of multifactorial origin and are associated with genetic, environmental factors, age, and oxidative stress, among others; the latter factor is one of the most influential in ocular diseases, directly affecting the processes of autophagy activity. Alteration of the normal functioning of autophagy processes can interrupt organelle turnover, leading to the accumulation of cellula…
Revision of asterolepidoid antiarch remains from the Ogre Formation (Upper Devonian) of Latvia
2020
The Frasnian (Upper Devonian) antiarch Walterilepis speciosa was first described in 1933 (as Taeniolepis) on the basis of a single specimen. The newly collected material has allowed the head to be described in a more detail, especially the nuchal and paranuchal plates. Other newly described elements include bones of the pectoral appendages and trunk armour, demonstrating a rather high and short trunk armour. The shape and proportions of the head and trunk armour suggest the attribution of Walterilepis to the family Pterichthyodidae; it is most probably closely related to Lepadolepis from the Late Frasnian of Germany. Whilst W. speciosa is endemic to the Latvian part of the Baltic Devonian B…
Estimating Tree Health Decline Caused by Ips typographus L. from UAS RGB Images Using a Deep One-Stage Object Detection Neural Network
2022
Various biotic and abiotic stresses are causing decline in forest health globally. Presently, one of the major biotic stress agents in Europe is the European spruce bark beetle (Ips typographus L.) which is increasingly causing widespread tree mortality in northern latitudes as a consequence of the warming climate. Remote sensing using unoccupied aerial systems (UAS) together with evolving machine learning techniques provide a powerful tool for fast-response monitoring of forest health. The aim of this study was to investigate the performance of a deep one-stage object detection neural network in the detection of damage by I. typographus in Norway spruce trees using UAS RGB images. A Scaled…
Histological characteristics of the vertebral intercentra of Metoposaurus diagnosticus (Temnospondyli) from the Upper Triassic of Krasiejów (Upper Si…
2012
ABSTRACTOsteohistological characteristics of the large temnospondyl amphibian Metoposaurus diagnosticus from the Upper Triassic of Poland (Krasiejów locality) were determined using vertebral intercentra thin-sections from different regions and growth stages. The intercentra showed a trabecular structure in both the endochondral and periosteal domains. Endochondral ossification developed first, and the primary bone occurs near the periphery with a higher degree of remodelling in the centre. Periosteal bone deposition begins later; first on the ventral side, continuing laterally and finally onto the dorsal side. Periosteal growth rate was initially very rapid, and then subsequently decreased …
Isopodes Aselloïdes stygobies d’Espagne récoltés par J. Notenboom et I. Meijers, III — Le genre Proasellus: A — Espèces oculées ou microphtalmes
1992
Samples collected in underground waters of Spain by Ine Meijers and Jos Notenboom demonstrated the presence of some oculated asellids previously known: Proasellus coiffaiti, P. coxalis, and P. meridianus, and also four new stygophilous species, more or less depigmented, with different stages of regression of the ocular system: P. beticus n. sp., P. ortizi n. sp., P. aragonensis n. sp., and P. ebrensis n. sp. These forms represent relict populations of ancient epigean species. The anophthalmous species of the Aquitanian Basin, Pyrenees, and Iberian Peninsula are more closely related to P. beticus and P. ortizi than to the Recent epigean species P. coxalis and P. meridianus.