172 research outputs found
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
A contribution to the data on tench (Tinca tinca L., Cyprinidae, pisces) distribution in Serbia
The studies on the ichthyofauna of Serbia that have been conducted so far indicate the sporadic tench (Tinca tinca L.) presence in typical habitats. The hydroenvironmental conditions necessary for the survival of this fish species are highly variable and, generally, are more favourable in the northern part of the country (the Vojvodina Province). Although the tench presence has been registered at over 30 sites, there is a tendency of a decrease in population abundance. This is due to the reduction of the surface area of the macrophyte-covered flood zones induced by the damming and regulation of rivers, high water level fluctuations, and water amount reduction in the majority of watercourses, a massive increase in the number of allochthonous phytofagous species, reservoir sediment deposition, water quality deterioration and other factors. The tench conservation status in Serbia is officially designated as Low Risk - Least Concern. It may be transferred to a higher category if the tendency towards deterioration of survival conditions for the species should continue
CHEMICAL EVALUATION OF AUTOCHTHONOUS VARIETY 'PROKUPAC' RED WINE WITH THE ADDITION OF SELECTED AROMATIC HERBS
The quality parameters and chemical composition (total phenolics, total flavonoids and total anthocyanins) of the red wine obtained from the autochthonous variety 'Prokupac' (Vitis vinifera L.) with the addition of the selected aromatic herbs (Pimpinella anisum L., Cinnamomum zeylanicum, Artemisia absinthium and Glycyrrhiza glabra) were examined in two consequtive vintages (2013-2014). The differences in contents of total extract, reducing sugars and ash between the studied samples were observed, but with no statistical significance between both examined years and analyzed wines. 'Prokupac' red wines with the addition of aromatic herbs stood out with significantly higher contents of total phenolics (371.4-594.3 mg GAE L-1) and total flavonoids (136.2-243.2 mg CTE L-1) while lower total anthocyanins content was noticed, when compared to 'Prokupac' red wine used as control (p<0.05). The unfavourable weather conditions in the vintages 2013 and 2014, reflected notably on the quality of the obtained wine. To analyze the correlations between wine quality parameters and the similarity of individual wine samples, Principal Component Analysis (PCA) was used
Factors affecting elimination of polycyclic aromatic hydrocarbons from traditional smoked common carp meat
Smoking techniques have been progressively improved and different procedures have been developed in different regions for treating fish. In these times, the technology is mainly used for enrichment of fish with specific taste and odour, to extend the shelf-life of these perishable products and appearance required widely on the market. A lot of chemical contaminants such as polycyclic aromatic hydrocarbons (PAHs) are formed during the combustion of fuel in the smoking process. PAHs are a group of compounds that have been the subject of great concern in the recent years due to their toxic, mutagenic and/or carcinogenic potentials to humans. These fact can have a significant impact on the acceptance of these products by consumers. In this review article, the objective is to describe factors affecting elimination of polycyclic aromatic hydrocarbons from traditional smoked common carp meat
Galactic Gradients, Postbiological Evolution and the Apparent Failure of SETI
Motivated by recent developments impacting our view of Fermi's paradox
(absence of extraterrestrials and their manifestations from our past light
cone), we suggest a reassessment of the problem itself, as well as of
strategies employed by SETI projects so far. The need for such reevaluation is
fueled not only by the failure of searches thus far, but also by great advances
recently made in astrophysics, astrobiology, computer science and future
studies, which have remained largely ignored in SETI practice. As an example of
the new approach, we consider the effects of the observed metallicity and
temperature gradients in the Milky Way on the spatial distribution of
hypothetical advanced extraterrestrial intelligent communities. While,
obviously, properties of such communities and their sociological and
technological preferences are entirely unknown, we assume that (1) they operate
in agreement with the known laws of physics, and (2) that at some point they
typically become motivated by a meta-principle embodying the central role of
information-processing; a prototype of the latter is the recently suggested
Intelligence Principle of Steven J. Dick. There are specific conclusions of
practical interest to be drawn from coupling of these reasonable assumptions
with the astrophysical and astrochemical structure of the Galaxy. In
particular, we suggest that the outer regions of the Galactic disk are most
likely locations for advanced SETI targets, and that intelligent communities
will tend to migrate outward through the Galaxy as their capacities of
information-processing increase, for both thermodynamical and astrochemical
reasons. This can also be regarded as a possible generalization of the Galactic
Habitable Zone, concept currently much investigated in astrobiology.Comment: 30 pages, 2 figure
Supplementary material for the article: Perusko, M.; van Roest, M.; Stanic-Vucinic, D.; Simons, P. J.; Pieters, R. H. H.; Cirkovic Velickovic, T.; Smit, J. J. Glycation of the Major Milk Allergen β-Lactoglobulin Changes Its Allergenicity by Alterations in Cellular Uptake and Degradation. Molecular Nutrition and Food Research 2018, 62 (17). https://doi.org/10.1002/mnfr.201800341
Supplementary material for: [https://doi.org/10.1002/mnfr.201800341]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2212
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
Laudatores Temporis Acti, or Why Cosmology is Alive and Well - A Reply to Disney
A recent criticism of cosmological methodology and achievements by Disney
(2000) is assessed. Some historical and epistemological fallacies in the said
article have been highlighted. It is shown that---both empirically and
epistemologically---modern cosmology lies on sounder foundations than it is
portrayed. A brief historical account demonstrates that this form of
unsatisfaction with cosmology has had a long tradition, and rather meagre
results in the course of the XX century.Comment: 11 pages, no figures; a criticism of astro-ph/0009020; Gen. Rel.
Grav., accepted for publicatio
Comparative Profiling of Microplastics in Differently sized Manila Clams from South Korea by Nile Red Staining and μFTIR
The high bioavailability of microplastics (MP) to marine biota has led to the contamination of seafood products. The safety of shellfish as food has become questionable due to the potential health risks associated with MP. As such, microplastics ingestion by commonly consumed shellfish is being investigated. In this study, market samples of clams (Ruditapes philippinarum, n=101) from South Korea were segregated into two different sizes (small and large) and analysed for microplastics contamination. Using alkaline digestion, MP were extracted and subsequently quantified using two of the most commonly used techniques in the field- Nile red staining (NRS) and μFTIR imaging [1], [2]. With NRS, the small (n= 51) and large (n= 50) clams were analysed individually. On the other hand, 8 composite subsamples (30 small and 31 large clams) were subjected to μFTIR imaging. The average MP concentration based on NRS was 4.3 ± 5.2 MP/ g ww (wet weight of soft tissue) considering both small and large clams. In the subsamples, 3.2 ± 1.6 MP/ g ww and 3.8 ± 1.7 MP/g ww were detected based on μFTIR and NRS, respectively. NRS showed 18-75% higher MP quantity compared to μFTIR. This was considered to be a consequence of the co-staining of remnants of undigested biological which was confirmed by additional staining using DAPI. Due to this overestimation, only μFTIR data was utilized for the comparative analysis of the differently sized clams. The MP abundance in both groups was comparable, with the small and large clams having 2.7 ± 1.7 MP/g ww and 3.6 ± 1.6 MP/g ww, respectively. Similarly, there was no significant difference observed in the concentration of MP fibers and MP non-fibers. In the small clams, only PS (polystyrene) and PET (polyethylene terephthalate) were identified from the fibers. In contrast, PP (polypropylene), PS (polystyrene), PE, and PET were found from the fibers that came from the large clams. The same 4 synthetic polymers were detected from the non-fibers obtained from both groups. Overall, PS was the most prominent type, accounting for 35- 49% of total detected MP. In terms of MP size, 20-50μm was the most abundant followed by 50-100μm. Relative to the weight of the samples, the quantity of MP, classified according to size and polymer type, was similar in both groups. In summary, the size of the clams had no effect on the MP content as suggested by the analogous concentrations of MP with respect to shape, size, and polymer identity. In addition, despite the simplicity, low-cost, and growing popularity of NRS, this method should be used with caution due to its propensity to overestimate MP quantity
Supplementary data for article: Smiljanic, K.; Apostolovic, D.; Trifunovic, S.; Ognjenovic, J.; Perusko, M.; Mihajlovic, L.; Burazer, L.; van Hage, M.; Cirkovic Velickovic, T. Subpollen Particles Are Rich Carriers of Major Short Ragweed Allergens and NADH Dehydrogenases: Quantitative Proteomic and Allergomic Study. Clinical and Experimental Allergy 2017, 47 (6), 815–828. https://doi.org/10.1111/cea.12874
Supporting information for: [https://doi.org/10.1111/cea.12874]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2468]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3126
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