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Polychlorinated dibenzo- para -dioxins (PCDDs) and dibenzofurans (PCDFs) (collectively and colloquially referred to as 'dioxins') as well as polychlorinated biphenyls (PCBs) are persistent and ubiquitous environmental contaminants that may unintentionally enter and accumulate along the food chain. Owing to their chronic toxic effects in humans and bioaccumulative properties, their presence in feed and food requires particular attention. One important exposure pathway for consumers is consumption of milk and dairy products. Their transfer from feed to milk has been studied for the past 50 years to quantify the uptake and elimination kinetics. We extracted transfer parameters (transfer rate, transfer factor, biotransfer factor and elimination half-lives) in a machine-readable format from seventy-six primary and twenty-nine secondary literature items. Kinetic data for some toxicologically relevant dioxin congeners and the elimination half-lives of dioxin-like PCBs are still not available. A well-defined selection of transfer parameters from literature was statistically analysed and shown to display high variability. To understand this variability, we discuss the data with an emphasis on influencing factors, such as experimental conditions, cow performance parameters and metabolic state. While no universal interpretation could be derived, a tendency for increased transfer into milk is apparently connected to an increase in milk yield and milk fat yield as well as during times of body fat mobilisation, for example during the negative energy balance after calving. Over the past decades, milk yield has increased to over 40 kg/d during high lactation, so more research is needed on how this impacts feed to food transfer for PCDD/Fs and PCBs. [ABSTRACT FROM AUTHOR]

This study examines the volumetric, viscometric and UV–vis characteristics of L-Citrulline in water and aqueous saccharides at atmospheric pressure across the whole concentration range and the absorber operating temperature range of 293.15 K -313.15 K. Density, partial molar volume, apparent molar isobaric expansion, Hepler's constant and hydration number were among the examined volumetric parameters, and viscosity coefficients, viscosity deviation and free energy for viscous flow activation were among the examined viscometric parameters. Stronger interactions between L-Citrulline and L-Arabinose were indicated by the increase in the transfer characteristics in the following order: L-Arabinose > D-xylose. A comparison of the taste behaviours of L-Citrulline in water and in an aqueous solution of saccharides has also been attempted. L-Citrulline interacts with all solvents in a significant way, as evidenced by the UV–visible spectra suggested by the shift in UV–visible absorption maxima that correspond with a rise in L-Citrulline content in the solvent systems chosen. [Display omitted] • Solvation behaviour of L-Citrulline was examined via volumetric, viscometric and UV–vis study. • L-Arabinose interacted strongly with L-citrulline as compared to D-xylose. • L-Citrulline is likely to have a tendency to break structural bonds in aqueous solutions. • Over hydrophobic–hydrophobic interactions, ion-hydrophilic interactions predominate. [ABSTRACT FROM AUTHOR]

The experimental data from acoustic, volumetric, and viscometric studies has been used to investigate significant changes in two amino acids, L-phenylalanine and L-arginine, in aqueous solutions of two ionic liquids, 1-butyl-3-methylimidazolium bromide, [BMIM][Br], and tributylmethylammonium chloride, [TBMA][Cl], at T = (293.15 - 313.15) K and experimental pressure P = 101.3 kPa. The limiting apparent molar parameters (volume, V0ϕ, and isentropic compressibility, K0ϕ,s) are evaluated from apparent molar volume, Vϕ, and apparent molar isentropic compressibility, Kϕ,s, respectively. Simultaneously, the corresponding empirical parameters, Sv and Sk, are also calculated. The experimental data is used to calculate the transfer characteristics, ∆trV0ϕ and ∆tr K0ϕ,s, of amino acids from water to aqueous solutions of ionic liquid. Using Jones-Dole equation, the viscosity data is used to evaluate viscosity B-coefficients. All these physicochemical properties are collectively used to gather information regarding all proximities and intermolecular interactions in ternary (L-phenylalanine/L-arginine + water + ionic liquid) solutions.

The ternary systems containing Water, Ascorbic acid (AA) and ZnSO4·7H2O were investigated using three approaches namely volumetric studies, viscosity studies and conductance studies. The solvent systems used were 2, 4 and 6% (by weight) of AA in water. The studies were conducted at four temperatures (303.15–318.15 K with an interval of 5 K) and pressure 0.1 MPa with concentration of ZnSO4·7H2O in the solution ranging from 0.01 to 0.12 m. Various parameters like partial molar volume (ϕv), apparent molar volume (ϕ v o) , Hepler's constant ((d 2 ϕ v o / d T 2) p) , partial molar expansibility (ϕ E o) and transfer volume (Δ t r ϕ v o) have been evaluated from volumetric studies. The viscosity studies have yielded Jones-Dole parameters (A and B) and free energy of activation per mole for solvent (Δ μ 1 0 ‡ ) and solute (Δ μ 2 0 ‡ ) . The conductance data has been used to calculate molar conductance (Λm), limiting molar conductance (Λ m o) and Walden product (Λ m o η o) . The results of these studies agree with each other and have concluded the structure breaker behavior of ZnSO4·7H2O in the solvent system containing AA and water. [ABSTRACT FROM AUTHOR]

1,2-unsaturated pyrrolizidine alkaloids and their N -oxides (PA/PANO) are plant toxins that are produced by several hundreds of plant species. Due to the pronounced liver toxicity and carcinogenicity of certain PAs, their presence in food and feed has raised concern. However, since PA-producing weeds cannot generally be prevented on grassland and Senecio species often occur in high densities, the transfer of PAs into muscle and liver of dairy cattle, goat and sheep was determined. In 28-day feeding studies extracts of tansy ragwort (Jacobaea vulgaris Gaertn.) were administered orally in three dose levels per animal species. Of the administered Senecio PAs only jacobine, jaconine and jacoline could be detected in relevant quantities by LC-MS/MS in the muscle and liver tissues of the three animal species. The calculated transfer parameters show a low transfer of total PAs into muscle (transfer factors: 0.0004–0.0009) and liver (transfer factors: 0.0008–0.0030), which is lower than reported for other typical contaminants and residues in the literature. This selective transfer can be explained by the rumen passage, during which the other Senecio PAs are largely and rapidly transformed to fully saturated metabolites. These ruminal metabolites were not detected in muscle and liver. No evidence of bioaccumulation of PAs in muscle and liver was observed. • Low transfer of pyrrolizidine alkaloids in muscle and liver of dairy animals. • Only the Senecio PA jaconine, jacoline and jacobine were detected. • Contents of PA in muscle and liver were dose dependent. • Resistance to ruminal metabolization is one explanation for selective transfer. • Elimination of the major amount of PA from muscle and liver expected within 48 h. [ABSTRACT FROM AUTHOR]

Physical properties such as density (ρ), sound speed (u) and viscosity (η) for varied compositions of a saccharide (sucrose) in water and mixed aqueous tributylmethylammonium chloride solvent media has been scrutinised at five discrete temperatures ranging (293.15 K - 313.15 K) and under ambient pressure (101.3 kPa). The empirically procured data has been employed to enumerate different volumetric, acoustic and viscometric parameters like apparent molar parameters (Kϕ,s, Vϕ), partial molar parameters (K0ϕ,s, V0ϕ), transfer parameters (K0ϕ,s,tr, V0ϕ,tr, Btr), hydration number, pair and triplet interaction coefficients, solvation number, viscosity B-coefficient etc. The temperature derivative of viscosity B-coefficient i.e. dB/dT values have been utilized to examine structure making ability of the solute. Also, Gibbs free energy of activation for both solute and solvent has been determined and the influence of temperature on the solute-solvent interactions has been addressed. Moreover, the co-sphere overlap model has been employed for better comprehension of various prevalent intermolecular interactions in the considered systems.

[Display omitted] • Binary and ternary solutions of Asp in water and aqueous saccharides have been investigated. • Asp has ASV values in the sour range. • Asp acts as a structure maker in the presence of L-arabinose and D-xylose. • The bathochromic shift of Π- Π ∗ absorption band of Asp takes place in aqueous saccharides. • Ion-ion and ion-hydrophilic interactions take place in the solutions. In this study, we report the density, viscosity, taste behavior and UV– Vis spectrophotometry results of L-Aspartic acid (Asp) in aqueous solutions of L-arabinose and D-xylose over an integral composition regime (2.0 wt%, 2.5 wt%, and 3.0 wt%) at atmospheric pressure (P = 101 kPa) and at temperature ranges of (293.15, 298.15, 303.15, 308.15, and 313.15) K. The various densimetric and rheological parameters such as apparent molar volume (V ϕ), apparent molar volume at infinite dilution (V ϕ 0), apparent molar isobaric expansion at infinite dilution (E ϕ 0), Hepler's constant ( ∂ 2 V Φ 0 / ∂ T 2) P , relative viscosity (η r ) , viscosity coefficients (B J a n d A F ), Gibbs free energy of activation of viscous flow of solvent and solute (Δ μ 1 # , 0 a n d Δ μ 2 # , 0 respectively), and corresponding change in enthalpy Δ H 2 # , 0 , entropy Δ S 2 # , 0 , apparent molar volume of transfer at infinite dilution (V É ¸ , t r 0) viscosity B-coefficients of transfer (B J , t r ), interaction coefficients (using the McMillan-Mayer theory), dB/dT and solvation number (S n) have been calculated using the experimentally collected physical characteristic data (density and viscosity). Variation of these parameters with concentration and temperature were analyzed in the light of ion-ion, ion–dipole and ion-hydrophilic interactions between solute (L-Aspartic acid)-cosolute (L-arabinose and D-xylose) in aqueous medium. An effort has also been made to compare the taste behaviours of the amino acid in water and in an aqueous solution of saccharides, as the taste behaviour is separated into four basic taste qualities in distinct ranges. To access different common intermolecular interactions in the systems under consideration, the cosphere overlap model has also been used. A detailed evaluation of the results from the thermodynamic and physicochemical parameters shows that Asp acts as a structure builder when L-arabinose/D-xylose is present. The preservation of effective ionic interactions in the studied systems was further confirmed by UV spectral analysis. [ABSTRACT FROM AUTHOR]

The study of the fate of atmospheric release and transport of Tritium requires an understanding of the exchange/transfer of Tritium (HTO) from within the compartments; air, soil, and plant systems. The Tritium transfer parameters within these compartments are used in specific activity models to compute TFWT and OBT in terrestrial plants and are highly dependent on the site-specific conditions. Hence a study was carried out to generate site-specific Tritium transport model parameters in the tropical environment of Tarapur which receives the atmospheric releases of Tritium from nuclear facilities operating at this site, on the West coast of India. The paper presents the details of the study carried out in Tarapur, India. The transfer parameters generated through this study are soil water to air moisture HTO transfer ratio: CR s , plant water to air moisture HTO transfer ratio: R pa, and plant water to soil water HTO transfer ratio: R pw. The geometric mean and geometric standard deviation (GSD) of the transfer ratios, CR s , R pa and R pw determined were found to be 0.50 (GSD: 3.52), 0.53 (GSD: 2.51) and 1.12 (GSD: 2.58), respectively. In addition, the Tritium scavenging ratio, surface loading, and wet deposition velocity were also derived and were found to be 1.59 ± 1.32, 1.21 × 10−2 Bq m−2 s−1, and 7.91 × 10−2 m s−1, respectively. The study has generated a set of site-specific model input parameters for a tropical coastal site of Tarapur, India, and details are discussed in the manuscript. • The terrestrial tritium transport model assumes air, soil, and plant compartments. • HTO or TFWT was determined in air moisture, soil water, vegetation, and rainwater. • Derived tritium scavenging ratio, surface loading, and wet deposition velocity. • Site-specific tritium transport model parameters generated at Tarapur. [ABSTRACT FROM AUTHOR]

Balancing networks, originally introduced by Aspnes et al. (Proceedings of the 23rd Annual ACM Symposium on Theory of Computing, pp. 348-358, May 1991), represent a new class of distributed, low-contention data structures suitable for solving many fundamental multi-processor coordination problems that can be expressed as balancing problems. In this work, we present a mathematical study of the combinatorial structure of balancing networks, and a variety of its applications.Our study identifies important combinatorial transfer parameters of balancing networks. In turn, necessary and sufficient combinatorial conditions are established, expressed in terms of transfer parameters, which precisely characterize many important and well studied classes of balancing networks such as counting networks and smoothing networks. We propose these combinatorial conditions to be “balancing analogs” of the well known Zero-One principle holding for sorting networksWithin the combinatorial framework we develop, our first application is in deriving combinatorial conditions, involving the transfer parameters, which precisely delimit the boundary between counting networks and sorting networks. [ABSTRACT FROM AUTHOR]

[Display omitted] • Density and speed of sound data were measured for determination of volumetric properties. • Interactions between caffeine and protic ionic liquids were studied. • Hydrophobic-interactions dominates for PIL with linger alkyl anionic chain length. • UV–Visible spectroscopy performed to evaluate electrostatic interactions. A comprehensive study on volumetric and spectroscopic properties of ternary solutions [water + protic ionic liquids (PILs) + caffeine (CAF)] was performed. Volumetric and compressibility properties were evaluated at different concentrations and temperatures, by measuring density and speed of sound of solutions. The newly synthesized PILs, ethanolammonium acetate; [EAAc] and ethanolammonium hexanoate; [EAHx] was used as co-solute. The density and speed of sound have been estimated at four different temperatures (298.15 K to 313.15 K) and at 0.1 MPa. Using these experimental data, apparent molar-volume, -isentropic compressibility, volumes of transfer were evaluated to understand the solute–solute, solute–solvent and solute–cosolute interactions occurring within the ternary solutions. At lower concentrations, negative transfer volumes indicate the presence of hydrophobic interactions among components of PILs (cations/anions) and CAF. The transfer volumes become positive as the concentration of PILs rises, implying that hydrophilic interactions were strengthened. In addition, UV–visible spectroscopic analysis was also performed to evaluate the nature of interactions. Hydrogen bonding interactions were also suggested based on the hyperchromic shift observed in UV absorption when aqueous CAF was titrated with PILs solutions. Physico-chemical analysis of the PILs-caffeine system are essential for comprehending the kinds of interactions that may occur in liquid combinations used for therapeutic drug delivery. [ABSTRACT FROM AUTHOR]

The study of the fate of atmospheric release and transport of Tritium requires an understanding of the exchange/transfer of Tritium (HTO) from within the compartments; air, soil, and plant systems. The Tritium transfer parameters within these compartments are used in specific activity models to compute TFWT and OBT in terrestrial plants and are highly dependent on the site-specific conditions. Hence a study was carried out to generate site-specific Tritium transport model parameters in the tropical environment of Tarapur which receives the atmospheric releases of Tritium from nuclear facilities operating at this site, on the West coast of India. The paper presents the details of the study carried out in Tarapur, India. The transfer parameters generated through this study are soil water to air moisture HTO transfer ratio: CR s , plant water to air moisture HTO transfer ratio: R pa, and plant water to soil water HTO transfer ratio: R pw . The geometric mean and geometric standard deviation (GSD) of the transfer ratios, CR s , R pa and R pw determined were found to be 0.50 (GSD: 3.52), 0.53 (GSD: 2.51) and 1.12 (GSD: 2.58), respectively. In addition, the Tritium scavenging ratio, surface loading, and wet deposition velocity were also derived and were found to be 1.59 ± 1.32, 1.21 × 10 -2 Bq m -2 s -1 , and 7.91 × 10 -2  m s -1 , respectively. The study has generated a set of site-specific model input parameters for a tropical coastal site of Tarapur, India, and details are discussed in the manuscript., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Under the International Atomic Energy Agency (IAEA) MODARIA (Modelling and Data for Radiological Impact Assessments) Programme, there has been an initiative to improve the derivation, provenance and transparency of transfer parameter values for radionuclides from feed to animal products that are for human consumption. A description of the revised MODARIA 2016 cow milk dataset is described in this paper. As previously reported for the MODARIA goat milk dataset, quality control has led to the discounting of some references used in IAEA's Technical Report Series (TRS) report 472 (IAEA, 2010). The number of Concentration Ratio (CR) values has been considerably increased by (i) the inclusion of more literature from agricultural studies which particularly enhanced the stable isotope data of both CR and F m and (ii) by estimating dry matter intake from assumed liveweight. In TRS 472, the data for cow milk were 714 transfer coefficient (F m ) values and 254 CR values describing 31 elements and 26 elements respectively. In the MODARIA 2016 cow milk dataset, F m and CR values are now reported for 43 elements based upon 825 data values for F m and 824 for CR. The MODARIA 2016 cow milk dataset F m values are within an order of magnitude of those reported in TRS 472. Slightly bigger changes are seen in the CR values, but the increase in size of the dataset creates greater confidence in them. Data gaps that still remain are identified for elements with isotopes relevant to radiation protection. [ABSTRACT FROM AUTHOR]

Under the MODARIA (Modelling and Data for Radiological Impact Assessments Programme of the International Atomic Energy Agency), there has been an initiative to improve the derivation, provenance and transparency of transfer parameter values for radionuclides. The approach taken for animal products is outlined here and the first revised table for goat milk is provided. Data from some references used in TRS 472 were removed and reasons given for removal. Particular efforts were made to improve the number of CR (concentration ratio) values which have some advantages over transfer coefficients. There is little difference in most of the new CR and F m (transfer coefficient) values for goat milk compared with those in TRS 472. In TRS 472, 21 CR values were reported for goat milk. In the 2015 dataset for goat milk CR values for a further 14 elements are now included. The CR and F m values for only one element (Co) were removed. [ABSTRACT FROM AUTHOR]

Abstract: Concentration ratios (CRs) are used to derive activity concentrations in wild plants and animals. Usually, compilations of CR values encompass a wide range of element–organism combinations, extracted from different studies with statistical information reported at varying degrees of detail. To produce a more robust estimation of distribution parameters, data from different studies are normally pooled using classical statistical methods. However, there is inherent subjectivity involved in pooling CR data in the sense that there is a tacit assumption that the CRs under any arbitrarily defined biota category belong to the same population. Here, Bayesian inference has been introduced as an alternative way of making estimates of distribution parameters of CRs. This approach, in contrast to classical methods, is more flexible and also allows us to define the various assumptions required, when combining data, in a more explicit manner. Taking selected data from the recently compiled wildlife transfer database (http://www.wildlifetransferdatabase.org/) as a working example, attempts are made to refine the pooling approaches previously used and to consider situations when empirical data are limited. [Copyright &y& Elsevier]

Abstract: Environmental assessments to evaluate potentials risks to humans and wildlife often involve modelling to predict contaminant exposure through key pathways. Such models require input of parameter values, including concentration ratios, to estimate contaminant concentrations in biota based on measurements or estimates of concentrations in environmental media, such as water. Due to the diversity of species and the range in physicochemical conditions in natural ecosystems, concentration ratios can vary by orders of magnitude, even within similar species. Therefore, to improve model input parameter values for application in aquatic systems, freshwater concentration ratios were collated or calculated from national grey literature, Russian language publications, and refereed papers. Collated data were then input into an international database that is being established by the International Atomic Energy Agency. The freshwater database enables entry of information for all radionuclides listed in ICRP (1983), in addition to the corresponding stable elements, and comprises a total of more than 16,500 concentration ratio (CRwo-water) values. Although data were available for all broad wildlife groups (with the exception of birds), data were sparse for many organism types. For example, zooplankton, crustaceans, insects and insect larvae, amphibians, and mammals, for which there were CRwo-water values for less than eight elements. Coverage was most comprehensive for fish, vascular plants, and molluscs. To our knowledge, the freshwater database that has now been established represents the most comprehensive set of CRwo-water values for freshwater species currently available for use in radiological environmental assessments. [Copyright &y& Elsevier]

• Interactions of citrate salts in aqueous [Emim][HSO 4 ] solutions were studied. • Density, speed of sound and viscosity were measured at different temperatures. • The effect of concentration and temperature on the solutions was studied. • Kosmotropic and chaotropic nature of added solute was studied. • Ion/hydrophobic-hydrophobic interactions were more prevalent in the solution. In the present work the density, speed of sound and viscosity (ƞ) data for trilithium citrate and triammonium citrate in aqueous [Emim][HSO 4 ] are determined experimentally over a range of concentration (0.0369–0.0514) mol kg−1 and temperature between 293.15 and 313.15 K. Using the density and speed of sound data the volumetric and compressibility parameters are evaluated. By graphical fitting of the evaluated parameters in some standard relations the partial molar parameters i.e. standard molar volumes ( V o ϕ) and standard molar compressibilities ( K ° ϕ , s ) are calculated. The transfer parameters of volume (Δ tr V ° ϕ) and compressibility (Δ tr K ° ϕ , S ) studies evaluated using the partial molar parameters are used to deduct the solute-solvent interactions by means of the cosphere overlap model which shows that the hydrophilic-hydrophilic and ion-hydrophilic interactions are less dominant in the solution over the hydrophobic-hydrophobic and ion-hydrophobic interactions. The viscosity data is utilized to calculate the relative viscosity (η r) and viscosity B -coefficient. The Hepler's constant and first temperature derivative of B -coefficients (dB/dT) has been used to analyze whether solute acts as structure maker or structure breaker in the solution. [ABSTRACT FROM AUTHOR]

Apparent molar volumes ( V2, φ) and heat capacities ( C p2, φ) of glycine in known concentrations (1.0, 2.0, 4.0, 6.0, and 8.0 mol⋅kg−1) of aqueous formamide (FM), acetamide (AM), and N, N-dimethylacetamide (DMA) solutions at T=298.15 K have been calculated from relative density and specific heat capacity measurements. These measurements were completed using a vibrating-tube flow densimeter and a Picker flow microcalorimeter, respectively. The concentration dependences of the apparent molar data have been used to calculate standard partial molar properties. The latter values have been combined with previously published standard partial molar volumes and heat capacities for glycine in water to calculate volumes and heat capacities associated with the transfer of glycine from water to the investigated aqueous amide solutions, $\Delta\overline{V}_{\mathrm{2,tr}}^{\mathrm{o}}$ and $\Delta\overline{C}_{p\mathrm{2,tr}}^{\mathrm{o}}$ respectively. Calculated values for $\Delta\overline{V}_{\mathrm{2,tr}}^{\mathrm{o}}$ and $\Delta\overline{C}_{p\mathrm{2,tr}}^{\mathrm{o}}$ are positive for all investigated concentrations of aqueous FM and AM solutions. However, values for $\Delta\overline{C}_{p\mathrm{2,tr}}^{\mathrm{o}}$ associated with aqueous DMA solutions are found to be negative. The reported transfer properties increase with increasing co-solute (amide) concentration. This observation is discussed in terms of solute + co-solute interactions. The transfer properties have also been used to estimate interaction coefficients. [ABSTRACT FROM AUTHOR]

• Thermophysical properties of glycine/glycylglycine with betaine hydrochloride were studied. • Apparent molar properties were evaluated to understand the solute-drug interactions. • Results indicated dominance of hydrophilic-hydrophilic interactions over hydrophobic interactions. • Structure breaking behaviour of amino acid and dipeptide in aqueous drug solutions. Density (ρ), ultrasonic velocity (u) and viscosity (η) for an amino acid (glycine) and a dipeptide (glycylglycine) in aqueous and (0.1, 0.2 and 0.3) mol kg−1 binary aqueous betaine hydrochloride media at six different temperatures, T = (293.15–318.15) K and under atmospheric pressure (0.1 MPa) have been determined. Various volumetric, compressibility and rheological parameters such as apparent molar parameters (V ϕ , K ϕ,s), partial molar parameters (V0 ϕ, K0 ϕ,s), transfer parameters ( V 0 ϕ , t r , K 0 ϕ , s , t r , B t r ) viscosity coefficients (A and B), hydration number (n H) etc. have been computed from the experimentally measured data. The structure breaking ability of each solute has been examined through the negative sign of Hepler's constant (∂E0 ϕ /∂T) p values and a positive sign of dB dT (temperature derivative of B-coefficient) values. Moreover, the cosphere overlap model has been employed for the comprehension of different sorts of intermolecular interactions predominating in the studied ternary solutions. [ABSTRACT FROM AUTHOR]

• Physicochemical studies of L-histidine/L-serine with diphenhydramine hydrochloride were studied. • Apparent molar properties were evaluated to understand the solute-drug interactions. • Results indicated dominance of hydrophilic-hydrophilic interactions over hydrophobic interactions. • Structure breaking behaviour of both amino acids in aqueous drug solutions. Thermophysical properties for varying concentrations of essential (L-histidine) and non-essential (L-serine) amino acids in water and (0.05–0.15) mol kg−1 mixed aqueous diphenhydramine hydrochloride solvent system has been deliberated at different temperatures ranging (293.15−318.15) K and ambient pressure (101.3 kPa). The experimentally obtained data has been utilized to compute different volumetric, compressibility and rheological parameters such as apparent molar volume (V ϕ), partial molar volume (V0 ф) , partial molar expansibility (E0 ϕ) , apparent molar isentropic compression (K ϕ,s) , partial molar isentropic compression (K0 ϕ,s) , hydration number (n H), transfer parameters, viscosity coefficients etc. The structure breaking ability of the solute molecules has been comprehended using Hepler′s constant (temperature derivative of partial molar expansibility at constant pressure) and dB/dT (temperature derivative of viscosity B -coefficient) values. Further, by using the co-sphere overlap model various sorts of solute-drug interactions prevailing in the systems have been discussed. [ABSTRACT FROM AUTHOR]

• Density, speed of sound and viscosity data is used to interpret results. • Ion-hydrophobic and hydrophobic-hydrophobic interactions are more dominant in solution. • Both L-valine and L-isoleucine acts as structure breaker in the solution. • The cosphere overlap model is used to explain negative Δ tr V Φ 0 values. • Hydration number and Viscosity B-coefficients are calculated. The present work deals with experimental determination of density, speed of sound and viscosity (ƞ) data for L-valine and L-isoleucine in aqueous [Emim][HSO 4 ] over range of concentration (0.0301–0.0702) mol kg−1 and temperature (293.15–313.15 K). The density and speed of sound data are used to evaluate the volumetric and compressibility parameters. Through the graphical fitting of the evaluated parameters in some standard relations the limiting apparent molar volume ( V o ϕ) and Limiting apparent molar isentropic compression ( K ° ϕ , s ) are calculated. The transfer parameters of volume (Δ tr V ° ϕ) and compressibility (Δ tr K ° ϕ , S ) studies evaluated using the limiting apparent molar parameters are used to deduct the solute–solvent interactions by means of the cosphere overlap model which shows that the hydrophilic-hydrophilic and ion-hydrophilic interactions are less dominant in the solution over the hydrophobic-hydrophobic and ion-hydrophobic interactions. The viscosity data is utilized to calculate the relative viscosity (η r) and viscosity B -coefficient. The Helper's constant and first temperature derivative of B -coefficients (dB/dT) has been used to analyze whether solute acts as structure maker or structure breaker in the solution. [ABSTRACT FROM AUTHOR]

Abstract: An ability to predict radionuclide activity concentrations in biota is a requirement of any method assessing the exposure of biota to ionising radiation. Within the ERICA Tool fresh weight whole-body activity concentrations in organisms are estimated using concentration ratios (the ratio of the activity concentration in the organism to the activity concentration in an environmental media). This paper describes the methodology used to derive the default terrestrial ecosystem concentration ratio database available within the ERICA Tool and provides details of the provenance of each value for terrestrial reference organisms. As the ERICA Tool considers 13 terrestrial reference organisms and the radioisotopes of 31 elements, a total of 403 concentration ratios were required for terrestrial reference organisms. Of these, 129 could be derived from literature review. The approaches taken for selecting the remaining values are described. These included, for example, assuming values for similar reference organisms and/or biogeochemically similar elements, and various simple modelling approaches. [Copyright &y& Elsevier]

Abstract: The process of assessing risk to the environment following a given release of radioactivity requires the quantification of activity concentrations in environmental media and reference organisms. The methodology adopted by the ERICA Integrated Approach involves the application of concentration ratios (CR values) and distribution coefficients (K d values) for aquatic systems. Within this paper the methodologies applied to derive default transfer parameters, collated within the ERICA Tool databases, are described to provide transparency and traceability in the documentation process. Detailed information is provided for the CR values used for marine and freshwater systems. Of the total 372 CR values derived for the marine ecosystem, 195 were identified by literature review. For the freshwater system, the number of values based on review was less, but still constituted 129 from a total of 372 values. In both types of aquatic systems, 70–80% of the data gaps have been filled by employing “preferable” approaches such as those based on substituting values from taxonomically similar organisms or biogeochemically similar elements. [Copyright &y& Elsevier]

Abstract: It is demonstrated that using integrals, derivatives, and inflection points of the oil recovery data measured by imbibition tests on cores improves the accuracy of correlations of the matrix-to-fracture oil transfer data. The tri-exponential transfer functions with the present numerical approach yield a reliable technique to represent the experimental imbibition data. Accurately estimated function parameters allow the laboratory results to be scaled to field applications. Several issues pertaining to spontaneous imbibition as a recovery mechanism while waterflooding naturally fractured reservoirs are addressed. The contribution of the wettability and dead-end pores is also determined. The triple-exponential function for double-porosity systems is able to adjust to actual spontaneous imbibition trends observed in experiments conducted in naturally fractured cores. The analysis and interpretation of the results verify the considerations of the proposed mechanisms for fluid transfer from matrix to fracture. [Copyright &y& Elsevier]

Abstract: Radionuclide transfer parameters and dose-rates for an adult ringed seal from Svalbard have been determined based on empirical and estimated tissue activity concentrations and detailed dietary and habitat information. Whole-body equivalent concentration factors determined for anthropogenic radionuclides ranged from 101 (90Sr) to 102 (137Cs, 238Pu and 239,240Pu), while natural radionuclides ranged from 102 (210Pb) to 104 (210Po). Employing a dietary composition of 40% fish, 40% zooplankton and 20% benthic invertebrates, a whole-body biological half-life of 29 days was derived for 137Cs. A total dose-rate of approximately 0.19μGyh−1 (1.7mGya−1) was derived for an adult ringed seal; this dose-rate is virtually entirely attributable to the internal components of 210Po and 40K. The dose-rates associated with the presence of anthropogenically derived radionuclides in the present assessment fall many orders of magnitude below the dose-rates at which any biological effects would be expected. [Copyright &y& Elsevier]

Transfer parameters for contaminants in the environment are notoriously variable. It is not unusual to measure a geometric standard deviation (GSD) of tenfold, so that the 5th and 95th percentiles are 10,000-fold apart. Despite many years of research, there remain large uncertainties, and often risk assessors will use on-site data for the transfer parameters. This Perspective assesses, using radionuclides as an example, whether a few site-specific measurements are more reliable than the more generic data compiled by researchers around the world. Using the example of plant/soil concentration ratios for several radionuclides, if one knew nothing about the soils and plants to be assessed, the GSD would be about 5.7-fold. If one had extensive knowledge about the soils and plants, the GSD would only diminish to about 3.2-fold. If a GSD of 3.2 is the level of residual natural variation to expect for plant/soil concentration ratios (the error term in a formal analysis of variance), then any on-site data that are within an order of magnitude of generic data could not be considered significantly different from the generic data. An appropriate conclusion in this case would be that unless on-site data are significantly different from the generic data, then the on-site data should not be used exclusively and the generic data should be considered suitable. The inherent variability of transfer parameters is so large that generic data may often be the best choice. [ABSTRACT FROM AUTHOR]

An international review of radioecological data derived after the accident at the Fukushima Daiichi nuclear power plant was an important component of activities in working group 4 of the IAEA Models and data for radiological impact assessment, phase II (MODARIA II) programme. Japanese and international scientists reviewed radioecological data in the terrestrial and aquatic environments in Japan reported both before and after the accident. The environmental transfer processes considered included: (a) interception and retention radionuclides by plants, (b) loss of radionuclides from plant and systemic transport of radionuclides in plants (translocation), (c) behaviour of radiocaesium in soil, (d) uptake of radionuclides from soil by agricultural crops and wild plants, (e) transfer of radionuclides from feedstuffs to domestic and wild animals, (f) behaviour of radiocaesium in forest trees and forest systems, (g) behaviour of radiocaesium in freshwater systems, coastal areas and in the ocean, (h) transport of radiocaesium from catchments through rivers, streams and lakes to the ocean, (i) uptake of radiocaesium by aquatic organisms, and (j) modification of radionuclide concentrations in food products during food processing and culinary preparation. These data were compared with relevant global data within IAEA TECDOC-1927 'Environmental transfer of radionuclides in Japan following the accident at the Fukushima Daiichi Nuclear Power Plant'. This paper summarises the outcomes of the data collation and analysis within MODARIA II work group 4 and compares the Japan-specific data with existing radioecological knowledge acquired from past and contemporary radioecological studies. The key radioecological lessons learned are outlined and discussed., (© 2022 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights reserved.)

[Display omitted] • Hydration properties of saccharides in water and in aqueous calcium lactate solutions were studied. • The volumetric properties were evaluated from density and speed of sound data. • Hydrophobic-ionic type of interactions were concluded on the basis of volumetric and 1H NMR spectroscopic analysis. • The saccharides remain in sweet taste range also in presence of calcium lactate. The solute-solvent interactions governing the hydration behaviour of saccharide [D(+)-glucose, sucrose and D(+)lactose monohydrate) molecules were studied in aqueous solution of calcium salt at temperatures (298.15 K 313.15 K) and at atmospheric pressure. The volumetric properties were evaluated from experimentally measured densities and speed of sound data. The nature of interactions influencing the taste behaviour of saccharides in presence of calcium lactate is evaluated from apparent specific volume and apparent specific isentropic compressibility values. The volumetric transfer parameters (Δ t Z 2 ° = Δ t V 2 ° or Δ t K ° s,2) were evaluated and the magnitude of these parameters were analysed on the basis of co-sphere overlap model. Among various interactions occurring in the system, hydrophobic types of interactions were found to be the dominating one. The 1H NMR of the studied system was recorded and from the variation in chemical shift (Δδ) it was further concluded the presence of hydrophobic-ionic types of interactions. [ABSTRACT FROM AUTHOR]

In this investigation, thermophysical properties like density, speed of sound and viscosity of solutions of glycyl-glycyl-glycine (0.05–0.40) mol·kg−1 were studied with water and aqueous solvent (tartaric acid). The solutions were experimentally calculated with in temperature range of (298.15 and 318.15) K and at pressure (0.1 MPa). The obtained experimental outcomes were further taken to compute the parameters like apparent molar volume, limiting apparent molar volumes, limiting apparent molar volumes of transfer, the hydration number from volumetric data and properties like apparent molar isentropic compression, limiting apparent molar isentropic compression, limiting apparent molar isentropic compression of transfer and the hydration number from acoustic data of the studied solutions. The experimental viscosity values were used in the Jones-Dole equation to obtain viscosity coefficients A and B. The computed activation parameters of the studied system were explained on the lines of transition state theory. These experimental and computed parameters and further, their alterations with molal concentration and temperature were discussed from the point of view of ionic-hydrophilic, hydrophilic-hydrophilic and hydrophilic-hydrophobic operational in the system. • Molecular interactions between glycyl-glycyl-glycine in water and in aqueous tartaric acid solutions are studied. • The volumetric, compressibility, acoustic and viscometric methods are used to interpret results. • Solute-solvent interactions predominate over solute-solute interactions. • Glycyl-glycyl-glycine behaves as a structure breaker in water and in aqueous tartaric acid solutions. [ABSTRACT FROM AUTHOR]

In this study, the solvation behaviour of monosaccharide's in aqueous solutions of newly synthesized ionic liquid: cholinium propanoate [Chl][Pro] has been studied at various temperatures and concentrations. The volumetric properties of two monosaccharides (viz. D (+)glucose and D (+)-xylose) were evaluated from density and speed of sound data. Apparent molar volume, V 2,φ and apparent molar isentropic compressibility, K s,2,φ calculated from experimental data were used to evaluate respective infinite dilution values (X 2 º = V 2 º or K º s,2). The volumetric transfer volumes (Δ t V 2 º or Δ t K º s,2) were also evaluated to analyze the solute-co-solute interactions. The Δ t V 2 º and Δ t K º s,2 values reveal that the interaction between ionic liquid and monosaccharides increases with concentration and temperature. The positive transfer parameter reveals hydrophilic-ionic interactions as evaluated from structural interaction model. Image 1 • Solute-solvent interactions of monosaccharides in aq. ionic liquid have been studied. • Positive Δ t V 2 º and Δ t K º s,2 values for D (+)Glucose in aq. [Chl][Pro] have been observed. • Positive transfer values suggest the dominance of hydrophilic type of interactions. • D (+)-xylose demonstrated both positive and negative Δ t V 2 º values. • Negative transfer values suggest dominance of hydrophobic types of interactions. [ABSTRACT FROM AUTHOR]