Analysis of the Dynamics of Marine Structures and Species with Criterial Mathematical Models

The influence of the area of artificial substrates (collectors) on the biological parameters of populations of mussels (Mytilus galloprovincialis Lamarck) during their cultivation in the Black Sea has been investigated. For growing mollusks, four types of collectors were used, with different relative areas (ω), i.e., with different ratios of the substrate area (S) per unit length of the collector (L), which were 0.09, 0.21, 0.34, and 0.55. It was found that, during a 1.5-year cultivation, the density (N, ind./m) and biomass (B, kg/m) change and reach a certain stationary state, determined by the relative area of the substrate. It was shown that, on collectors with a higher value of ω, there was a decrease in the average length (L, mm) and weight (W, g) of the mollusk yield. The Boysen–Jensen method was used to calculate the total production of mollusks (P), elimination (E), and specific production (P/B coefficient) for each type of reservoir, and it was shown that P increased with an increase in the substrate area, while E and P/B coefficients decreased. Based on the analysis of the obtained results, it was concluded that during the cultivation of mussels these parameters are regulated by density-dependent population factors (intraspecific competition) for space (substrate) and food.

Mutual Comparison Studies of Mono and Di Cations in Binary and Ternary Aqueous Electrolytes Solution at 298.15 K

Densities and viscosities of binary and ternary electrolytes solution have been determined experimentally at 298.15 K. The results obtained from density and viscosity measurement have been used to calculate apparent molar volume φv partial molar volume φov at infinite dilution, relative viscosities hrel, A and B coefficients, and free energies of activation of viscous flow of solvent Δ µ10# and solute Δ µ20. The results are discussed in terms of the dehydration effect of the weak ion-ion and strong ion-solvent interactions. The properties of these systems are discussed in terms of the charge, size, and hydrogen bonding effect.

The Einstein A and B coefficients

The Einstein A and B coefficients for atom–photon reactions are defined: they describe absorption, stimulated emission, and spontaneous emission. We calculate B and consequently find A by the Einstein trick. The procedure is validated by application of detailed balance. Separating out frequencies permits introduction of the spectral lineshape function (normalized line profile). A reformulation describes transitions involving single atomic states and single field modes. This points to a link with quantum electrodynamics.

Viscometric Study of n-Hexylammonium and n-Octylammonium perchlorates in Binary Non-Aqueous Solvents Probed by a Physicochemical Approach in the Temperature Ranging 298 - 328K at Atmospheric Pressure

Viscosity data were measured for n-hexyl ammonium perchlorate (C6H13NH3ClO4)(HAP) and n-octylammonium perchlorate (C8H17NH3ClO4) (OAP) in acetonitrile (AN), dimethylsulfoxide (DMSO) and their binary mixtures containing 0, 20, 40, 60, 80 and 100 mol%DMSO at 298, 308, 318 and 328 K in the concentration range 60-350×10-4 mol.dm-3. The data was further examined to evaluate ion-ion and ion-solvent interactions in terms of the Aand B coefficients of the Jones-Dole equation respectively. A and B coefficients for the studied electrolytes came out be to be positive throughout the whole composition range. However, smaller values of A as compare to B reveal the dominance of ion-solvent interaction over ion-ion interactions especially at 60 mol% DMSO in AN-DMSO mixtures. Thermodynamic parameters like free energy, enthalpy and entropy change of activation of the viscous flow have also been evaluated by using Erying transition state theory.

Effect of the Temperature and Solvents on the Solvolysis of Barium Bromide in Aqueous-Organic Solutions: Volumetric and Viscometric Study

Volumetric and viscometric properties of solutions containing barium bromide in an aqueous solution of ethylene glycol and 1,4-dioxane have been discussed at different temperatures such as 298.15K 303.15K, 308.15K, and 313.15K. The Masson’s equation was used to determine the apparent molar volume, V_ϕ, standard partial molar volume, V_ϕ^0, molar expansibilities,E_ϕ^0 by taking the density data. The values of viscosity and density were used in the Jones-Dole equation to find the viscosity B coefficients, which were used to estimate the ion-solvent interactions. The values of Hepler’s constant (∂^2 V_ϕ^0/ ∂T2)p and the viscosity B-coefficients have been used to deduce the solvent structure-promoting or structure breaking tendency of the salt in the studied mixtures. In the current study, the positive values of Hepler’s constant and the negative values of dB/dT show that barium bromide in the considered solvents mainly behaves as a structure promoter.

Viscometric Studies of Ion Solvation of Some Alkali Metal Salts in 2-Aminoethanol + N,N-Dimethylacetamide Binary Mixtures at 298.15 K and 308.15 K

Densities (ρ) and viscosities (η) of lithium perchlorate (LiClO4), sodium perchlorate (NaClO4), potassium thiocyanate (KSCN), tetrabutyl-ammonium thiocyanate (Bu4NSCN), tetrabutylammonium tetraphenylborate (Bu4NBPh4) and tetrabutylammonium perchlorate (Bu4NClO4) were measured in binary mixed solutions of 2-aminoethanol (AE) and N,N-dimethylacetamide (DMA) containing 25, 50, 60, 80 and 100 mol % DMA in the concentration range (3-500) ×10-4 mol kg-1 at 298.15 K and 308.15 K temperatures. The density and viscosity data were analyzed using the Jones-Dole equation in the form ηr = 1 + A(C1/2) + BC for unassociated electrolytes and viscosity A and B-coefficients were obtained from the plots of of ηr – 1/C1/2 versus C1/2. The A-coefficients obtained from the analysis of Jones-Dole equation are positive as well as negative. The positive values indicate the solvation of ions in solutions of binary mixtures (AE + DMA) especially in 50 and 60 mol% DMA. The viscosity B-coefficients of all these electrolytes were positive and large in case of cations and were split into their respective ionic (B±) coefficient values using a method reported by Gill and Sharma. The viscosity B-coefficients values were increasing with the increase increasing DMA composition in the binary mixed solvent system of AE + DMA but decreasing with increasing temperature from 298.15 K to 308.15 K. The obtained results indicate about the preferential solvation of ions i.e. Li+, Na+, K+, Bu4N+ and Ph4B– ions and poor solvation of ClO4 – and SCN– ions. The results also revealed that these interactions get weaker with increase in temperature. The resulting B-coefficients and its dependence of temperature provide useful information regarding changes in the solvent structure.

LENGTH-WEIGHT RELATIONSHIP AND RELATIVE CONDITION FACTOR OF 31 SMALL-SIZED FISHES OF THE PARANAPANEMA RIVER BASIN

Studies on length-weight relationships are of great importance in fishery assessments. These studies are substantial to evaluate fish population dynamics, and in communion with the relative condition factor, could provide an estimation of potential acting environmental conditions. In this paper, we evaluated the length weight relationship and relative condition factor of small sized fish species. Fish were sampled quarterly between the years 2012-2013 and 2018-2020 in lagoons and tributaries of Rosana and Taquaruçu reservoirs, located at the lower Paranapanema River basin, Brazil. The standard length (SL) in millimeters and weight (W) in grams were measured, and the length-weight relationship was calculated using linear regression analysis (W = log (a) + b log (SL)). After, the relative condition factor (Kn) was calculated from the expression We = a.SLb. Thus, the length-weight relationships of 31 species were calculated in each environment considered, giving rise to 74 population allometric coefficients (b) and relative condition factors (Kn). As result, 24 b coefficients were concentrated between 2.5 and 3.5 and seven were out of the confidence interval, while the 74 Kn values demonstrated close to the central mean and not statistical different. Our results are relevant to the conservation of fish fauna, improving knowledge regarding small-sized fish and those living environment.

The Effects of Artemia Cyst Harvesting on the Salt Lake Ecosystem

In Russia, the main stocks of Artemia cysts and cyst harvesting activities are concentrated in Western Siberia. About 1,100 tons of cysts are harvested annually, including 180 tons in the Kurgan Region and 140 tons from Medvezhye Lake (about 2 % of their world harvest). The purpose of this study was to determine the degree of influence of Artemia cyst harvesting on the ecosystem of a salt lake in a case study of Medvezhye Lake. The main trophic components of the ecosystem – phytoplankton, zooplankton, and zoobenthos – were analyzed. The salinity of the brine of Medvezhye Lake varied between 110 and 320 g/dm3 in different years. Phytoplankton in the lake function throughout the year. They are characterized by small cell sizes, low biomass (0.76±0.24 mg/L) and daily production (1.03±0.18 mgO2/L or 0.3±0.05 gC/m2), and high levels of A/B and P/B coefficients. Zooplankton and zoobenthos are represented mainly by Artemia. The biomass of Artemia shrimp reached 21.9±3.2 mg/L (219 kg/ha) on average during 1995-2018. During this period, the stock of cysts formed annually in the lake was 114.5±14.3 kg/ha; the harvest was 23.7±3.0 kg/ha (21 % of the stock). The main components of the ecosystem – phytoplankton – Artemia shrimp – Artemia cysts – were produced annually in the following proportions: 8390:2678:115 kg/ha·year (75:24:1 %). The removal of 23.7 kg/ha of the cysts (0.22 % of the production of all components) from the lake is negligible compared to the other components of the ecosystem. The residual density of cysts after harvesting, which is necessary for the reproduction of the Artemia population for the next season during the 1st generation, is 10 kg/ha. Averaged data indicate that the amount of Artemia cysts left in the ecosystem of Medvezhye Lake after cyst harvesting is 91 kg/ha, i.e. 9 times greater than the minimum required density. The results reported in the present study indicate that the current level of cyst harvesting cannot have any significant impact on the ecosystem of the hypersaline lake

Sleeping Beauties in Case Law

A challenge in computational legal research is the quantitative assessment of “relevance” in a network of court decisions. The term “sleeping beauty” (SB) was coined to denote an article that received almost no attention immediately after publication, but suddenly received multiple citations many years later. These publications can be identified by calculating their Beauty coefficient (B-coefficient). In this contribution, we apply approaches used for identifying SBs to decisions arising from the Court of Justice of the European Union (CJEU). We compared B-coefficients of CJEU cases with their centrality scores from classical algorithms from network analysis, finding that these measures tend to correlate. We discuss the implications of this that are interesting for legal scholars, acknowledging that future work is required to calibrate the scale of the time variable in the B-coefficient formula for finer-grained application to case law. Our study’s setup provides a foundation for new case law analytics methodologies that extends the power of traditional network analysis techniques for answering questions about the behavior of European courts.