Search results for "otos"
showing 10 items of 857 documents
Results from DROXO IV. EXTraS discovery of an X-ray flare from the Class I protostar candidate ISO-Oph 85
2016
X-ray emission from Young Stellar Objects (YSOs) is crucial to understand star formation. A very limited amount of X-ray results is available for the protostellar (ClassI) phase. A systematic search of transient X-ray phenomena combined with a careful evaluation of the evolutionary stage offer a widely unexplored window to our understanding of YSOs X-ray properties. Within the EXTraS project, a search for transients and variability in the whole XMM-Newton archive, we discover transient X-ray emission consistent with ISO-Oph 85, a strongly embedded YSO in the rho Ophiuchi region, not detected in previous time-averaged X-ray studies. We extract an X-ray light curve for the flare and determine…
A large temnospondyl humerus from the Rhaetian (Late Triassic) of Bonenburg (Westphalia, Germany) and its implications for temnospondyl extinction
2018
Temnospondyls are a group of basal tetrapods that existed from the Early Carboniferous to the Early Cretaceous. They were characteristic members of Permian and Triassic continental faunas around the globe. Only one clade, the Brachyopoidea (Brachyopidae and Chigutisauridae), is found as relics in the Jurassic of eastern Asia and the Cretaceous of Australia. The other Late Triassic clades, such as Plagiosauridae, Metoposauridae, and Cyclotsauridae, are generally believed to have gone extinct gradually before the end of the Triassic and putative Rhaetian records are stratigraphically poorly constrained. Temnospondyl humeri all show a similar morphological pattern, being stout, short, with wid…
New fossil arthropods (Notostraca and Insecta: Syntonopterida) in the Continental Middle Permian of Provence (Bas-Argens Basin, France).
2009
9 pages; Apart frequent and relatively common ichnites, only a few body fossils (Ostracoda) have been mentioned in the Red Continental Permian formations of Provence till these last years. During 2006 and 2007 field researches, new arthropods have been discovered in the Pradineaux Formation of the Bas-Argens. They are Triopsidae (Crustacea, Notostraca) and an insect wing (Syntonopteridae) corresponding to a new genus and species Gallolithoneura butchlii gen. et sp. n. This latter is the first insect record in the Permian of Provence and the youngest one of this enigmatic Carboniferous paleopteran family. As in the other French Permian basins (Lodève, Saint-Affrique), these discoveries demon…
Priming maritime pine megagametophytes during somatic embryogenesis improved plant adaptation to heat stress
2021
In the context of global climate change, forest tree research should be addressed to provide genotypes with increased resilience to high temperature events. These improved plants can be obtained by heat priming during somatic embryogenesis (SE), which would produce an epigenetic-mediated transgenerational memory. Thereby, we applied 37 °C or 50 °C to maritime pine (Pinus pinaster) megagametophytes and the obtained embryogenic masses went through the subsequent SE phases to produce plants that were further subjected to heat stress conditions. A putative transcription factor WRKY11 was upregulated in priming-derived embryonal masses, and also in the regenerated P37 and P50 plants, suggesting …
Strategies to Mitigate the Salt Stress Effects on Photosynthetic Apparatus and Productivity of Crop Plants
2018
Soil salinization represents one of the major limiting factors of future increase in crop production through the expansion or maintaining of cultivation area in the future. High salt levels in soils or irrigation water represent major environmental concerns for agriculture in semiarid and arid zones. Recent advances in research provide great opportunities to develop effective strategies to improve crop salt tolerance and yield in different environments affected by the soil salinity. It was clearly demonstrated that plants employ both the common adaptative responses and the specific reactions to salt stress. The review of research results presented here may be helpful to understand the physi…
C4-like photosynthesis and the effects of leaf senescence on C4-like physiology in Sesuvium sesuvioides (Aizoaceae).
2019
Sesuvium sesuvioides represents a young C4 lineage with C4-like metabolism: CO2 compensation points range between C4 and C3–C4 intermediate values, and Rubisco was detected in bundle sheath and mesophyll.
What is Vipp1 good for?
2018
While Vipp1 (also known as IM30) clearly is essential for proper biogenesis of thylakoid membranes in chloroplasts and cyanobacteria, the exact function of Vipp1/IM30 still remains unclear. The recent in vivo study of Gutu et al. now demonstrates that Vipp1/IM30 forms localized puncta specifically at highly curved membrane regions at the cell periphery. These Vipp1/IM30 puncta were found being highly dynamic under normal growth conditions, while it has recently been shown that they stably associate with membranes under high-light conditions. These observations, together with the observation that other Vipp1/IM30 homologous proteins also form puncta under stress conditions, indicate a protec…
In vivo photoprotection mechanisms observed from leaf spectral absorbance changes showing VIS–NIR slow-induced conformational pigment bed changes
2019
Abstract Regulated heat dissipation under excessive light comprises a complexity of mechanisms, whereby the supramolecular light-harvesting pigment–protein complex (LHC) shifts state from light harvesting towards heat dissipation, quenching the excess of photo-induced excitation energy in a non-photochemical way. Based on whole-leaf spectroscopy measuring upward and downward spectral radiance fluxes, we studied spectrally contiguous (hyperspectral) transient time series of absorbance A(λ,t) and passively induced chlorophyll fluorescence F(λ,t) dynamics of intact leaves in the visible and near-infrared wavelengths (VIS–NIR, 400–800 nm) after sudden strong natural-like illumination exposure. …
Synthetic conversion of leaf chloroplasts into carotenoid-rich plastids reveals mechanistic basis of natural chromoplast development
2020
Plastids, the defining organelles of plant cells, undergo physiological and morphological changes to fulfill distinct biological functions. In particular, the differentiation of chloroplasts into chromoplasts results in an enhanced storage capacity for carotenoids with industrial and nutritional value such as beta-carotene (provitamin A). Here, we show that synthetically inducing a burst in the production of phytoene, the first committed intermediate of the carotenoid pathway, elicits an artificial chloroplast-to-chromoplast differentiation in leaves. Phytoene overproduction initially interferes with photosynthesis, acting as a metabolic threshold switch mechanism that weakens chloroplast i…
GreenCut proteinCPLD49 ofChlamydomonas reinhardtiiassociates with thylakoid membranes and is required for cytochromeb6fcomplex accumulation
2018
The GreenCut encompasses a suite of nucleus-encoded proteins with orthologs among green lineage organisms (plants, green algae), but that are absent or poorly conserved in non-photosynthetic/heterotrophic organisms. In Chlamydomonas reinhardtii, CPLD49 (Conserved in Plant Lineage and Diatoms49) is an uncharacterized GreenCut protein that is critical for maintaining normal photosynthetic function. We demonstrate that a cpld49 mutant has impaired photoautotrophic growth under high-light conditions. The mutant exhibits a nearly 90% reduction in the level of the cytochrome b6 f complex (Cytb6 f), which impacts linear and cyclic electron transport, but does not compromise the ability of the stra…