20 research outputs found
Advanced Aspects of the Galactic Habitability
Context. Astrobiological evolution of the Milky Way (or the shape of its
"astrobiological landscape") has emerged as one of the key research topics in
recent years. In order to build precise, quantitative models of the Galactic
habitability, we need to account for two opposing tendencies of life and
intelligence in the most general context: the tendency to spread to all
available ecological niches (conventionally dubbed "colonization") and the
tendency to succumb to various types of existential catastrophes
("catastrophism"). These evolutionary tendencies have become objects of study
in fields such as ecology, macroevolution, risk analysis, and futures studies,
while a serious astrobiological treatment has been lacking so far. Aims. Our
aim is to numerically investigate the dynamics of opposed processes of
expansion (panspermia, colonization) and extinction (catastrophic mechanisms)
of life in the Galaxy. Methods. We employ a new type of numerical simulation
based on 1D probabilistic cellular automaton with very high temporal
resolution, in order to study astrobiological dynamics. Results. While the
largest part of the examined parameter space shows very low habitability
values, as expected, the remaining part has some observationally appealing
features that imply, among other things, a reduction in the amount of
fine-tuning necessary for resolving the Fermi paradox. Conclusions. Advanced
aspects of Galactic habitability are amenable to precision studies using
massive parallel computer simulations. There are regions of parameter space
corresponding to a quasi-stationary state satisfying observable constraints and
possessing viable SETI targets.Comment: Language corrected version, to appear in Astronomy & astrophysic
Galactic Punctuated Equilibrium: How to Undermine Carter's Anthropic Argument in Astrobiology
We investigate a new strategy which can defeat the (in)famous Carter's
"anthropic" argument against extraterrestrial life and intelligence. In
contrast to those already considered by Wilson, Livio, and others, the present
approach is based on relaxing hidden uniformitarian assumptions, considering
instead a dynamical succession of evolutionary regimes governed by both global
(Galaxy-wide) and local (planet- or planetary system-limited) regulation
mechanisms. This is in accordance with recent developments in both astrophysics
and evolutionary biology. Notably, our increased understanding of the nature of
supernovae and gamma-ray bursts, as well as of strong coupling between the
Solar System and the Galaxy on one hand, and the theories of "punctuated
equilibria" of Eldredge and Gould and "macroevolutionary regimes" of Jablonski,
Valentine, et al. on the other, are in full accordance with the regulation-
mechanism picture. The application of this particular strategy highlights the
limits of application of Carter's argument, and indicates that in the real
universe its applicability conditions are not satisfied. We conclude that
drawing far-reaching conclusions about the scarcity of extraterrestrial
intelligence and the prospects of our efforts to detect it on the basis of this
argument is unwarranted.Comment: 3 figures, 26 page
THE USE OF INTEGRATIVE MULTI-OMICS APPROACH IN CULTIVATION AND CHARACTERIZATION OF GUT BACTERIA RELATED TO MICROBIOTA-GUT-BRAIN AXIS AS A SOURCE FOR NEXT GENERATION PROBIOTICS
There has been an epidemic of various non-communicable
degenerative and autoimmune diseases,
strongly associated with the modern
lifestyle. Among them, neurodegenerative and
psychiatric disorders represent a huge burden on
society. Recently, all these diseases have been associated
with the gut microbiota dysbiosis. Gut
microbiota-host interaction research has been
greatly improved due to development of molecular
high-throughput techniques based on
various ‘omics’ techniques coupled with bioinformatics
and data science developments. However,
the mechanisms of the host–microbiota crosstalk
are still poorly understood. The NextGenBiotics
project proposes an innovative integrative
multi-omics research strategy for deciphering
the mechanism behind the cross-talk among
microbiota and gut-brain-axis. The 118 novel
NGPs candidates belonging to Dorea sp., Blautia
sp., Bacteroides sp., Roseburia sp., Sellimonas
sp., Faecalicatena sp., Phascolarctobacterium faecium,
and Faecalimonas sp. were cultivated. The
25 NGPs with confirmed safe status and potential
probiotic potential were screened in C. elegans
model for their effects on behavioural and neuronal
activity. The most prominent candidates
with ability to upregulate expression of genes
involved in neurotransmiting are further tested
in EAE (an animal model for MS) and CUMS depression
model. The specific microbiota-derived
metabolites have been identified as potential
neuro- and psycho-biotics. The NextGenBiotics is
highly ambitious project, dedicated to pioneering
work in the field of multi-omics studies related
to the cultivation of novel anaerobic NGPs
and the studying of their effect on MGBA. This
concept enabled studying bidirectional communication
between gut microbiota and brain
on the functional level that will significantly
contribute to the growing body data related to
MGBA. The results obtained during NextGenBiotics
determined the genes/metabolites and the
associated mechanisms involved in health-promoting
effects of NGPs in MGBA beyond stateof-
the-art, broadening the scientific knowledge
and opening up the possible novel therapeutic
approaches in prevention and therapy of neurodegenerative
and psychiatric diseases.Book of abstract: From biotechnology to human and planetary health XIII congress of microbiologists of Serbia with international participation Mikromed regio 5, ums series 24: 4th – 6th april 2024, Mona Plaza hotel, Belgrade, Serbi
Astrobiological Complexity with Probabilistic Cellular Automata
Search for extraterrestrial life and intelligence constitutes one of the
major endeavors in science, but has yet been quantitatively modeled only rarely
and in a cursory and superficial fashion. We argue that probabilistic cellular
automata (PCA) represent the best quantitative framework for modeling
astrobiological history of the Milky Way and its Galactic Habitable Zone. The
relevant astrobiological parameters are to be modeled as the elements of the
input probability matrix for the PCA kernel. With the underlying simplicity of
the cellular automata constructs, this approach enables a quick analysis of
large and ambiguous input parameters' space. We perform a simple clustering
analysis of typical astrobiological histories and discuss the relevant boundary
conditions of practical importance for planning and guiding actual empirical
astrobiological and SETI projects. In addition to showing how the present
framework is adaptable to more complex situations and updated observational
databases from current and near-future space missions, we demonstrate how
numerical results could offer a cautious rationale for continuation of
practical SETI searches.Comment: 37 pages, 11 figures, 2 tables; added journal reference belo
EMU Detection of a Large and Low Surface Brightness Galactic SNR G288.8-6.3
We present the serendipitous detection of a new Galactic Supernova Remnant
(SNR), G288.8-6.3 using data from the Australian Square Kilometre Array
Pathfinder (ASKAP)-Evolutionary Map of the Universe (EMU) survey. Using
multi-frequency analysis, we confirm this object as an evolved Galactic SNR at
high Galactic latitude with low radio surface brightness and typical SNR
spectral index of . To determine the magnetic field
strength in SNR G288.8-6.3, we present the first derivation of the
equipartition formulae for SNRs with spectral indices . The
angular size is 1.\!^\circ 8\times 1.\!^\circ 6 (107.\!^\prime 6 \times
98.\!^\prime 4) and we estimate that its intrinsic size is pc which
implies a distance of kpc and a position of pc above the
Galactic plane. This is one of the largest angular size and closest Galactic
SNRs. Given its low radio surface brightness, we suggest that it is about 13000
years old.Comment: Accepted for publication in The Astrophysical Journa