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The effect of the treatment with lyophilized antioxidant extracts of wild basil (Clinopodium vulgare L.) and basil (Ocimum basilicum L.) in rabbit meat on pH, colour and myoglobin changes during refrigerated and frozen storage was investigated. The experimental design included 3 groups of meat – one control and two treated with lyophilized plant extracts (in amount 1:100). The meat was derived from three carcass parts- loin, hind leg and fore leg The meat samples were stored at 4°C for 7 days, after that the storage proceeded for 90 days at -45°C. The study demonstrated different effect of the plant antioxidants on pH and colour, as well as the changes in the myoglobin and its redox forms that depended on the carcass part. The values of pH and decreased during frozen storage. The treatment with plant extracts and storage led to considerable discoloration of the meat from hind leg and fore leg, displayed by decrease of the redness, corresponding to lower percentage of OMb but higher of MetMb. The results suggest certain pro oxidative effect of the plant extracts in this study and require further research with different doses, storage times and temperatures in order to determine the optimal antioxidant application.

The incorporation of fiber-rich non-starchy wastes from various industries, into ready-to-eat extrudates, changes their structure and therefore affects their physical properties. The study explored the impact of varying levels of tomato pomace (ranging from 0% to 20%), moisture content in the mixture (ranging from 14.5% to 21.4% on a wet basis), and screw speed (ranging from 156 to 224 rpm) on the hardness of corn extrudates, as well as on parameters such as the number of pores, pore area, average pore size, and pore circularity. It was observed that, the inclusion of tomato pomace increases the hardness of the extrudates by decreasing the average pore size. On the other hand, the average pore size increases, and the hardness decreases with the increase of the screw speed. It was also observed that the higher initial moisture content of the mixtures increases the hardness and results in a more porous structure in the extruded products. The results show that the amount of tomato pomace and the process parameters significantly influence the structure of the extrudates.

In this article, we consider a discrete nonlinear third-order boundary value problem Δ3u(k−1)=λa(k)f(k,u(k)),k∈[1,N−2]Z,Δ2u(η)=αΔu(N−1),Δu(0)=−βu(0),u(N)=0,\left\{\phantom{\rule[-1.25em]{}{0ex}}\begin{array}{l}{\Delta }^{3}u\left(k-1)=\lambda a\left(k)f\left(k,u\left(k)),\hspace{1em}k\in {\left[1,N-2]}_{{\mathbb{Z}}},\hspace{1.0em}\\ {\Delta }^{2}u\left(\eta )=\alpha \Delta u\left(N-1),\Delta u\left(0)=-\beta u\left(0),\hspace{1em}u\left(N)=0,\hspace{1.0em}\end{array}\right. where N>4N\gt 4 is an integer, λ>0\lambda \gt 0 is a parameter. f:[1,N−2]Z×[0,+∞)→[0,+∞)f:{\left[1,N-2]}_{{\mathbb{Z}}}\times \left[0,+\infty )\to \left[0,+\infty ) is continuous, a:[1,N−2]Z→(0,+∞)a:{\left[1,N-2]}_{{\mathbb{Z}}}\to \left(0,+\infty ), α∈0,1N−1\alpha \in \left[0,\frac{1}{N-1}\right), β∈0,2(1−α(N−1))N(2−α(N−1))\beta \in \left[0,\frac{2\left(1-\alpha \left(N-1))}{N\left(2-\alpha \left(N-1))}\right), and η∈N−22+1,N−2Z\eta \in {\left[\left[\frac{N-2}{2}\right]+1,N-2\right]}_{{\mathbb{Z}}}. With the sign-changing Green’s function, we obtain not only the existence of positive solutions but also the multiplicity of positive solutions to this problem.

In this paper, we consider a fourth-order three-point boundary value problem. Despite the fact that the corresponding Green's function changes its sign on the square of its definition, we obtain the existence of at least one positive and decreasing solution under some suitable conditions. The results are based on the classical Krasosel'skii's fixed point theorem in cones. Then, we impose some sufficient conditions that allow us to deduce nonexistence results. In the end, some examples are given in order to illustrate our main results. [ABSTRACT FROM AUTHOR]

In this paper, a third-order ordinary differential equation coupled to three-point boundary conditions is considered. The related Green’s function changes its sign on the square of definition. Despite this, we are able to deduce the existence of positive and increasing functions on the whole interval of definition, which are convex in a given subinterval. The nonlinear considered problem consists on the product of a positive real parameter, a nonnegative function that depends on the spatial variable and a time dependent function, with negative sign on the first part of the interval and positive on the second one. The results hold by means of fixed point theorems on suitable cones.

The effect of treatment with aqueous antioxidant extracts of oregano (Origanum vulgare L.) and wild basil (Clinopodium vulgare L.) in refrigerated storage of raw poultry meat was studied. Physicochemical analyzes of meat samples were performed - total protein, ash, fat, dry matter, cooking loss and pH value in dynamics. The content of malondialdehyde (MDA) and the protein profile were determined. The microorganisms’ growth rate in meat during storage at 4°C for a period of 14 d was monitored. After the 7th d, the total number of mesophilic microorganisms in the meat samples increased to 7.00 log cfu/g, which is indicative of decay. A significant increase in pH value was observed after 14 d of storage, but there were no significant changes in total protein content and protein profile. In all meat samples, the amounts of MDA on days 7 and 14 were significantly below the thresholds indicated in the literature. Experimental groups treated with extracts showed lower values for MDA content compared to the control, which is an indication of certain inhibition of lipid oxidation processes in meat.

The article discusses a method applied for combining the results of Global Navigation Satellite Systems (GNSS) and 75-year old triangulation measurements to estimate the crustal movements in central western Bulgaria region. It was examined for joint analysis based on the results of GNSS with angular measurements of the first order triangulation network in Bulgaria during the period 1923–1930 year. As a result of the processing of GNSS and angular measurements, horizontal velocities of 15 points, strain rates, and rotation rates have been obtained. The results show dominating N–S extension at a rate of 1–2 mm/y and the deformation is not uniformly distributed over the studied area. The obtained results indicate the possibility of using old angular measurement of first-order triangulation points, together with GNSS data, to obtain estimates of the horizontal crustal movements.