相关论文: Evidence of molecular adaptation to extreme enviro…
A variety of genome transformations can occur as a microbial population adapts to a large environmental change. In particular, genomic surveys indicate that, following the transition to an obligate, host-dependent symbiont, the density of…
We address disequilibrum abundances of some simple molecules in the atmospheres of solar composition brown dwarfs and self-luminous extrasolar giant planets using a kinetics-based 1D atmospheric chemistry model. Our approach is to use the…
The detections of atomic hydrogen, heavy atoms and ions surrounding the extrasolar giant planet (EGP) HD209458b constrain the composition, temperature and density profiles in its upper atmosphere. Thus the observations provide guidance for…
Studying exoplanet atmospheres is essential for assessing their potential to host liquid water and their capacity to support life (their habitability). Each atmosphere uniquely influences the likelihood of surface liquid water, defining the…
We present a set of full evolutionary sequences for white dwarfs with hydrogen-deficient atmospheres. We take into account the evolutionary history of the progenitor stars, all the relevant energy sources involved in the cooling, element…
Most proteins must remain soluble in the cytosol in order to perform their biological functions. To protect against undesired protein aggregation, living cells maintain a population of molecular chaperones that ensure the solubility of the…
We calculated an atmospheric grid for hot mini-Neptune and giant exoplanets, that links astrophysical observable parameters- orbital distance and stellar type- with the chemical atmospheric species expected. The grid can be applied to…
Context. The long-term evolution of an atmosphere and the remote detectability of its chemical constituents are susceptible to how the atmospheric gas responds to stellar irradiation. The response remains poorly characterized for water and…
We use a model of aerosol microphysics to investigate the impact of high-altitude photochemical aerosols on the transmission spectra and atmospheric properties of close-in exoplanets, such as HD209458b and HD189733b. The results depend…
We perform an exhaustive analysis of genome statistics for organisms, particularly extremophiles, growing in a wide range of physicochemical conditions. Specifically, we demonstrate how the correlation between the frequency of amino acids…
The habitable zone (HZ) is commonly defined as the range of distances from a host star within which liquid water, a key requirement for life, may exist on a planet's surface. Substantially more CO2 than present in Earth's modern atmosphere…
We carry out a comparison between observations and hydrodynamic simulations of entropy profiles of groups and clusters of galaxies. We use the Tree+SPH GADGET code to simulate four halos of sizes in the M_500 = 1.0 - 16.e13 h^-1 Msun range,…
In previous warm-up chemical models of the low-mass star-forming region L1527, we investigated the evolution of carbon-chain unsaturated hydrocarbon species when the envelope temperature is slightly elevated to $T\approx 30$ K. These models…
A carbon-to-oxygen ratio (C/O) of around unity is believed to act as a natural separator of water- and methane-dominated spectra when characterizing exoplanet atmospheres. In this paper we quantify the C/O ratios at which this separation…
Although hypoxia is a major stress on physiological processes, several human populations have survived for millennia at high altitudes, suggesting that they have adapted to hypoxic conditions. This hypothesis was recently corroborated by…
Numerous epidemiological studies suggest febrile infections could confer long-term immunity to certain types of cancers, though the precise mechanisms for this phenomenon remain unclear. Systemic heat-shock responses to fever may be key to…
In order to investigate the physical and chemical properties of massive star forming cores in early stages, we analyse the excitation and abundance of four organic species, CH3OH, CH3OCH3, HCOOCH3 and CH3CH2CN, toward 29 Extended Green…
We use moderate-resolution spectra of nearby late K and M dwarf stars with parallaxes and interferometrically determined radii to refine their effective temperatures, luminosities, and metallicities. We use these revised values to calibrate…
The dynamic nature of life's ability to thrive in diverse and changing planetary environments suggests that habitability and survival depend on the evolutionary path and life adaptation to environmental conditions. Here we explore such…
(Abridged) There is a diverse chemical inventory in protostellar regions leading to the classification of extreme types of systems. Warm carbon chain chemistry sources, for one, are the warm and dense regions near a protostar containing…