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Bacteria transport through soil is a complex process particularly when the cells are released from solid manures and co-transported with particles. This study focuses on understanding of the Escherichia coli release from different particle fractions (0.25-, 0.5-, 1-, and 2-mm) of solid manure and evaluating different influent boundary conditions during cell release from manure and when a solid manure is applied to the soil. The 0.25-mm and 2-mm particle sizes resulted a greater cell release compared to 0.5-mm and 1-mm fractions (p < 0.05). The shape and magnitude of the cell release curves (CRCs) from the original manure bulk were mainly influenced by the two 0.25-mm and 2-mm fractions, respectively. The arithmetic mean for normalizing the CRCs and the time variable- based normalized CRCs for the manure-treated soil were the robust variables in evaluation of the experimental data. However, a single maximum bacteria concentration could provide the realistic dataset for the modeling process. Evaluation of the root-mean-squared-error and Akaike criterion showed that the two- and three-parametric models are recommended for simulating the cell release from solid manure in comparison with one parametric models. This study also suggests considering separate microbial release evaluations, with regards to influent concentration, for manure and manure-treated soils to propose best management practices for controlling bacteria pollution. Further research will reveal the key roles of different woody components and soluble material ratios for the various solid manures in bacteria release.

Summary: Background: There are currently no studies detailing cardiac troponin I (cTnI) release in normal horses post‐exercise using an analytically validated assay. These data are essential for selecting appropriate sampling times in equine athletes with suspected myocardial injury. Objective: To plot the magnitude and time course of cTnI release after maximal effort, using validated cTnI assays. Study design: Descriptive longitudinal study. Methods: Five clinically normal Standardbred racehorses in race training were included in the study. Horses were exercised in harness at near‐race intensity. Blood samples were taken immediately pre‐ and post‐exercise and then hourly for 24 h. Samples were analysed using the validated high‐sensitivity cTnI assay and a contemporary sensitivity cTnI assay. Results: Mean resting cTnI was 1.33 ± 0.6 s.d. ng/L (range, 0.82–2.33 ng/L) using assay A. All horses were below the detection limit at rest using assay B. Peak elevation occurred 2–6 h post‐exercise with both assays (mean, 4.6 ± 1.7 and 4.0 ± 2 h, respectively). Mean peak increase in cTnI was 11.96 ± 9.41 ng/L (range, 1.72–23.76 ng/L) using assay A. Peak concentrations were detectable in three of the horses using assay B and were between 0.039 and 0.051 μg/L (mean: 0.043 ± 0.006 μg/L). All horses returned to baseline within 24 h. Main limitations: A small (n = 5) convenience sample was used as random sampling was not logistically possible. Conclusions: All horses experienced an increase in cTnI post‐exercise, with peak occurring 2–6 h post‐exercise. Cardiac troponin I elevation was detected earlier using the high‐sensitivity assay, which may convey a diagnostic advantage. Targeted studies are needed to determine the significance of these increases. [ABSTRACT FROM AUTHOR]

The effect of process scale-up from 4 to 400-L high-shear granulator on the release kinetics of the active ingredient from pharmaceutical granules has been investigated. The dissolution and disintegration rates of the granules were measured simultaneously by the combination of UV/vis spectroscopy and static light scattering. The granule batches were found to consist of sub-populations with qualitatively different dissolution behavior: “weaker” granules that disintegrated during dissolution, and “stronger” granules that retained their size and from which the active ingredient was gradually leached. The existence of these sub-populations was attributed to non-uniform distribution of normal and shear forces that prevail in granulators of different size. This hypothesis was confirmed by preparing granules at increasing values of the Froude number at the 4-L scale, and observing a transition from the break-up dissolution mode to the leaching dissolution mode with increasing granule densification. The simultaneous observation of solute concentration and particle size distribution during granules dissolution proved to be a useful tool for the understanding of dissolution mechanisms and for identifying non-uniformities of process conditions that can occur during scale-up. [ABSTRACT FROM AUTHOR]

Monte Carlo simulations of the low- and high-conductivity Target/Ion Source systems used at Oak Ridge National Laboratory for effusion measurements are performed. Comparisons with the corresponding experimental data for the different geometries are presented and discussed. Independent checks of the simulation using data for simple geometries and using the conductance approach well known in vacuum technology are performed. A simulation-based comparison between the low- and high-conductivity systems is also presented. [Copyright &y& Elsevier]

Transfer of azo-dyes from dioctylphthalate core to binary mixtures of methanol+acetone with different compositions through poly(ureaurethane) (PUU) microcapsule membrane has been measured. The release curves were expressed by an exponential equation C(t)=Ceq(1−exp(−t/τ)) except for pure acetone, where C(t) is the concentration of the dye in the dispersing medium, Ceq that at the equilibrium state, t the elution time and τ a time constant. Ceq and τ are related to the chemical potentials and the diffusion coefficient of the dye, based on a simple theoretical model. The logarithm of τ was roughly proportional to the reciprocal of the absolute temperature, from which the activation energy Ea for the transfer of the dye was estimated. The value of Ea observed using acetone as the dispersing medium was much larger than that observed using methanol. In the curve of τ versus percentage weight of acetone w in the dispersing medium, a minimum was observed around w∼40%. The release curve for pure acetone had multi steps and did not agree with the theoretical prediction. These characteristic permeability properties were attributed to a structural change of the microcapsule membrane surface due to the interaction of the protective colloid and the dispersing medium. [Copyright &y& Elsevier]

A detailed model for simulating release curves from ISOL targets has been developed. The full 3D geometry is implemented using Geant-4. Produced particles are followed individually from production to release. The delay time is computed event by event. All processes involved: diffusion, effusion and decay are included to obtain the overall release curve. By fitting to the experimental data, important parameters of the release process (diffusion coefficient, sticking time, …) are extracted. They can be used to improve the efficiency of existing targets and design new ones more suitable to produce beams of rare isotopes. [Copyright &y& Elsevier]

The time course for the transfer of azo dyes from the microcapsule core of dioctylphthalate to the dispersing medium of methanol through a poly(ureaurethane) (PUU) membrane was measured for various average size microcapsules with a size distribution. The dye release curves are represented by a stretched exponential function C(t)=Ceq{1−exp [−(t/τeff)α]}, where C(t) is the concentration of the dye in methanol, Ceq that at the equilibrium state, and t the time. The exponent α decreased by increasing the variance of the size distribution of microcapsules. The effective time constant τeff was expressed by τeff=c0〈R2〉/κ(α), where 〈R2〉 and κ(α) are the mean square of microcapsule radius and a correction for the size distribution, respectively. The characteristic proportional constant, c0, was determined as 2.6±0.2 min/μm2. From the value of the constant, the diffusion coefficient of the azo dye in the PUU membrane was evaluated as 2.6×10−12 cm2/s. [Copyright &y& Elsevier]

We have studied the release curve for microcapsules with size distribution. On the basis of an analogy to the relaxation phenomena with multiple characteristic times, we propose a stretched exponential release curve for the system with size distribution and relate the release curve to the size distribution function of the microcapsule. This method was successfully applied to the transfer of azo-pigments from inner medium of dioctyl phthalate to dispersing medium of methanol through poly(ureaurethane) microcapsule membrane. [Copyright &y& Elsevier]

Bacteria transport through soil is a complex process particularly when the cells are released from solid manures and co-transported with particles. This study focuses on understanding of the Escherichia coli release from different particle fractions (0.25-, 0.5-, 1-, and 2-mm) of solid manure and evaluating different influent boundary conditions during cell release from manure and when a solid manure is applied to the soil. The 0.25-mm and 2-mm particle sizes resulted a greater cell release compared to 0.5-mm and 1-mm fractions ( p < 0.05). The shape and magnitude of the cell release curves (CRCs) from the original manure bulk were mainly influenced by the two 0.25-mm and 2-mm fractions, respectively. The arithmetic mean for normalizing the CRCs and the time variable- based normalized CRCs for the manure-treated soil were the robust variables in evaluation of the experimental data. However, a single maximum bacteria concentration could provide the realistic dataset for the modeling process. Evaluation of the root-mean-squared-error and Akaike criterion showed that the two- and three-parametric models are recommended for simulating the cell release from solid manure in comparison with one parametric models. This study also suggests considering separate microbial release evaluations, with regards to influent concentration, for manure and manure-treated soils to propose best management practices for controlling bacteria pollution. Further research will reveal the key roles of different woody components and soluble material ratios for the various solid manures in bacteria release., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)