SUBSTANTIATION OF THE METHOD OF MEAT SAMPLE PREPARATION FOR INSTRUMENTAL DETERMINATION OF CONSISTENCY

In recent years, there has been a transformation in the choice and lifestyle of Russian citizens. An increasing part of the population makes a more reasonable choice, taking into account all aspects, including the most important for meat products — these are organoleptic characteristics, in particular the consistency of the product. Consumers prefer products with the delicate, soft texture, expect good «biteness» and «cheweness». Therefore, preference is given to tender, juicy meat with a low content of connective tissue. The most commonly used method for testing meat consistency in laboratories around the world is a method that uses strength testing machines with a Warner-Bratzler blade (WB blade). In this work, the Shimadzu AGS-1kN universal testing machine (Japan) was chosen for research. Samples obtained from l. dorsi of pork and beef were selected as meat raw materials. To determine the optimal and reproducible method of sample preparation, some of them were subjected to heat treatment before analysis. In the study of samples without heat treatment, deviations from the average were more than 11%. After meat was cooked, a decrease in the relative standard deviation of the maximum shear stress from the average was achieved: from 11% in raw meat to 5% in a pork sample and 5.3% in a beef sample. The heat treatment of pre-cut samples led to a change in their geometric shape, which created additional difficulties for obtaining correct results, and also negatively affected the increase in the relative deviation to 15.5% for beef.In recent years, there has been a transformation in the choice and lifestyle of Russian citizens. An increasing part of the population makes a more reasonable choice, taking into account all aspects, including the most important for meat products — these are organoleptic characteristics, in particular the consistency of the product. Consumers prefer products with the delicate, soft texture, expect good «biteness» and «cheweness». Therefore, preference is given to tender, juicy meat with a low content of connective tissue. The most commonly used method for testing meat consistency in laboratories around the world is a method that uses strength testing machines with a Warner-Bratzler blade (WB blade). In this work, the Shimadzu AGS-1kN universal testing machine (Japan) was chosen for research. Samples obtained from l. dorsi of pork and beef were selected as meat raw materials. To determine the optimal and reproducible method of sample preparation, some of them were subjected to heat treatment before analysis. In the study of samples without heat treatment, deviations from the average were more than 11%. After meat was cooked, a decrease in the relative standard deviation of the maximum shear stress from the average was achieved: from 11% in raw meat to 5% in a pork sample and 5.3% in a beef sample. The heat treatment of pre-cut samples led to a change in their geometric shape, which created additional difficulties for obtaining correct results, and also negatively affected the increase in the relative deviation to 15.5% for beef

Chromosome Aberrations in Lymphocytes of Patients Undergoing Radon Spa Therapy: An Explorative mFISH Study

In the present exploratory study, we aim to elucidate the action of radon in vivo and to assess the possible health risks. Chromosome aberrations were analyzed in lymphocytes of two patients (P1, P2) undergoing radon spa therapy in Bad Steben (Germany). Both patients, suffering from painful chronic degenerative disorders of the spine and joints, received nine baths (1.2 kBq/L at 34 °C) over a 3-week period. Chromosome aberrations were analyzed before and 6, 12 and 30 weeks after the start of therapy using the high-resolution multiplex fluorescence in situ hybridization (mFISH) technique. For comparison, the lymphocytes from two healthy donors (HD1, HD2) were examined. P1 had a higher baseline aberration frequency than P2 and both healthy donors (5.3 ± 1.3 vs. 2.0 ± 0.8, 1.4 ± 0.3 and 1.1 ± 0.1 aberrations/100 analyzed metaphases, respectively). Complex aberrations, biomarkers of densely ionizing radiation, were found in P1, P2 and HD1. Neither the aberration frequency nor the fraction of complex aberrations increased after radon spa treatment, i.e., based on biological dosimetry, no increased health risk was found. It is worth noting that a detailed breakpoint analysis revealed potentially clonal aberrations in both patients. Altogether, our data show pronounced inter-individual differences with respect to the number and types of aberrations, complicating the risk analysis of low doses such as those received during radon therapy

Modelling radiation-induced cell cycle delays

Ionizing radiation is known to delay the cell cycle progression. In particular after particle exposure significant delays have been observed and it has been shown that the extent of delay affects the expression of damage such as chromosome aberrations. Thus, to predict how cells respond to ionizing radiation and to derive reliable estimates of radiation risks, information about radiation-induced cell cycle perturbations is required. In the present study we describe and apply a method for retrieval of information about the time-course of all cell cycle phases from experimental data on the mitotic index only. We study the progression of mammalian cells through the cell cycle after exposure. The analysis reveals a prolonged block of damaged cells in the G2 phase. Furthermore, by performing an error analysis on simulated data valuable information for the design of experimental studies has been obtained. The analysis showed that the number of cells analyzed in an experimental sample should be at least 100 to obtain a relative error less than 20%.Comment: 19 pages, 11 figures, accepted for publication in Radiation and Environmental Biophysic

Chronicles of nature calendar, a long-term and large-scale multitaxon database on phenology

We present an extensive, large-scale, long-term and multitaxon database on phenological and climatic variation, involving 506,186 observation dates acquired in 471 localities in Russian Federation, Ukraine, Uzbekistan, Belarus and Kyrgyzstan. The data cover the period 1890-2018, with 96% of the data being from 1960 onwards. The database is rich in plants, birds and climatic events, but also includes insects, amphibians, reptiles and fungi. The database includes multiple events per species, such as the onset days of leaf unfolding and leaf fall for plants, and the days for first spring and last autumn occurrences for birds. The data were acquired using standardized methods by permanent staff of national parks and nature reserves (87% of the data) and members of a phenological observation network (13% of the data). The database is valuable for exploring how species respond in their phenology to climate change. Large-scale analyses of spatial variation in phenological response can help to better predict the consequences of species and community responses to climate change.Peer reviewe

Phenological shifts of abiotic events, producers and consumers across a continent

Ongoing climate change can shift organism phenology in ways that vary depending on species, habitats and climate factors studied. To probe for large-scale patterns in associated phenological change, we use 70,709 observations from six decades of systematic monitoring across the former Union of Soviet Socialist Republics. Among 110 phenological events related to plants, birds, insects, amphibians and fungi, we find a mosaic of change, defying simple predictions of earlier springs, later autumns and stronger changes at higher latitudes and elevations. Site mean temperature emerged as a strong predictor of local phenology, but the magnitude and direction of change varied with trophic level and the relative timing of an event. Beyond temperature-associated variation, we uncover high variation among both sites and years, with some sites being characterized by disproportionately long seasons and others by short ones. Our findings emphasize concerns regarding ecosystem integrity and highlight the difficulty of predicting climate change outcomes. The authors use systematic monitoring across the former USSR to investigate phenological changes across taxa. The long-term mean temperature of a site emerged as a strong predictor of phenological change, with further imprints of trophic level, event timing, site, year and biotic interactions.Peer reviewe

SUBSTANTIATION OF THE METHOD OF MEAT SAMPLE PREPARATION FOR INSTRUMENTAL DETERMINATION OF CONSISTENCY

In recent years, there has been a transformation in the choice and lifestyle of Russian citizens. An increasing part of the population makes a more reasonable choice, taking into account all aspects, including the most important for meat products — these are organoleptic characteristics, in particular the consistency of the product. Consumers prefer products with the delicate, soft texture, expect good «biteness» and «cheweness». Therefore, preference is given to tender, juicy meat with a low content of connective tissue. The most commonly used method for testing meat consistency in laboratories around the world is a method that uses strength testing machines with a Warner-Bratzler blade (WB blade). In this work, the Shimadzu AGS-1kN universal testing machine (Japan) was chosen for research. Samples obtained from l. dorsi of pork and beef were selected as meat raw materials. To determine the optimal and reproducible method of sample preparation, some of them were subjected to heat treatment before analysis. In the study of samples without heat treatment, deviations from the average were more than 11%. After meat was cooked, a decrease in the relative standard deviation of the maximum shear stress from the average was achieved: from 11% in raw meat to 5% in a pork sample and 5.3% in a beef sample. The heat treatment of pre-cut samples led to a change in their geometric shape, which created additional difficulties for obtaining correct results, and also negatively affected the increase in the relative deviation to 15.5% for beef