Production Value Research Articles

Estimation of changes in carbon sequestration and its economic value with various stand density and rotation age of Pinus massoniana plantations in China

Plantations actively participate in the global carbon cycle and play a significant role in mitigating global climate change. However, the influence of forest management strategies, especially planting density management, on the biomass carbon storage and production value of plantations for ensuring carbon sink benefits is still unclear. In this study, we estimated the carbon sequestration and economic value of Pinus massoniana plantations with various stand densities and rotation ages using a growth model method. The results revealed that with increasing stand age, low-density plantations at 2000 trees·ha−1 (358.80 m3·ha−1), as well as high-density plantations at 4500 trees·ha−1 (359.10 m3·ha−1), exhibited nearly identical standing volumes, which indicated that reduced inter-tree competition intensity favors the growth of larger trees during later stages of development. Furthermore, an increase in planting density led to a decrease in the average carbon sequestration rate, carbon sink, and number of trees during the rapid growth period, indicating that broader spacing between trees is favorable for biomass carbon accumulation. Further, extending the rotation period from 15 to 20 years or 25 years and reducing the optimal planting density from 3000 to 2000 trees·ha−1 increased the overall benefits of combined timber and carbon sink income by 2.14 and 3.13 times, respectively. The results highlighted that optimizing the planting density positively impacts the timber productivity and carbon sink storage of Pinus massoniana plantations and boosts the expected profits of forest managers. Thus, future afforestation initiatives must consider stand age and planting density management to shift from a scale-speed pattern to a quality-benefit design.

Фотосинтез, минеральное питание и продуктивность лиственных и хвойных видов дендрофлоры центральной части Русской равнины

An ecological and physiological retrospective transformation of the data from the dry mass tables obtained by V.A. Usoltsev has been carried out for 7 coniferous and deciduous species (Larix sukaczewii, Picea abies, Pinus sylvestris, Betula alba, Quercus robur, Tilia cordata and Fraxinus excelsior) in the central part of the Russian Plain. In the age range from 5–20 to 80–200 years, the indicators of net photosynthetic productivity, net mineral productivity, net primary production, carbon sequestration, free oxygen emission and biological productivity have been determined at the organism level. When establishing these parameters, plants have been considered from the standpoint of ecology and the structure of a modular organism. The calculation of net mineral productivity has been carried out according to I.A. Muromtsev and V.M. Lebedev, and the net productivity of photosynthesis has been calculated according to A.A. Nichiporovich. A decrease in all physiological parameters with age has been recorded at a simultaneous increase in the ratio of root to photosynthetic potential (as an adaptive response to a decrease in the availability of nutrients). In all species, upon reaching the age of 20–30 years, a sharp decrease in the absorption activity of the roots has been revealed, which has stabilized at an extremely low level by the age of 50–60 years. The relationship between the listed plant indicators and their age for the studied species has been negative, and the relationship between mineral and biological productivity has been characterized as highly positive. In comparable age periods (30, 60 and 90 years), the studied species differed in nitrogen absorption by the root system by 21.7–28.0 times, in net photosynthetic productivity – by 4.4–7.0 times, in the value of net primary production – by 1.8–6.2 times, in nitrogen absorption – by 3.2– 6.1 times, in carbon sequestration and free oxygen emission – by 1.8–6.2 times, and in the mass of the whole plant – by 2.4–3.9 times. According to the accumulated dry mass, tree species at 90 years of age have been arranged in the following descending order: oak, spruce, larch, pine, linden, ash and birch.

Effect of deletion of protein 4.1R on proliferation, apoptosis and glycolysis of hepatocyte HL-7702 cells

To explore the effects of deletion of protein 4.1R on hepatocyte proliferation, apoptosis, and glycolysis and the molecular mechanisms. A 4.1R-/- HL-7702 cell line was constructed using CRISPR/Cas9 technique, and with 4.1R+/+HL-7702 cells as the control, its proliferative capacity and cell apoptosis were assessed using CCK-8 assay, EdU-488 staining, flow cytometry and Annexin V-FITC/PI staining at 24, 48, 72 h of cell culture. The changes in glucose uptake, lactate secretion, ATP production and pH value of the culture supernatant of 4.1R-/- HL-7702 cells were determined. The mRNA expressions of the key regulatory enzymes HK2, PFKL, PKM2 and LDHA in glycolysis were detected with qRT-PCR, and the protein expressions of AMPK, p-AMPK, Raptor and p-Raptor were determined using Western blotting. Western blotting and sequencing analysis both confirmed the successful construction of 4.1R-/- HL-7702 cell line. Compared with the wild-type cells, 4.1R-/- HL-7702 cells exhibited a lowered proliferative activity with increased cell apoptosis. The deletion of protein 4.1R also resulted in significantly decreased glucose uptake, lactate secretion and ATP production of the cells and increased pH value of the cell culture supernatant. qRT-PCR showed significantly decreased mRNA expressions of the key regulatory enzymes in glycolysis in 4.1R-/- HL-7702 cells. Compared with those in HL-7702 cells, the expression levels of AMPK and Raptor proteins were decreased while the expression levels of p-AMPK and p-Raptor proteins increased significantly in 4.1R-/- HL-7702 cells. Deletion of protein 4.1R in HL-7702 cells results in reduced proliferative capacity, increased apoptosis and suppression of glycolysis, and this regulatory mechanism is closely related with the activation of the downstream AMPK-mTORC1 signaling pathway.

Herbage accumulation and nutritive value of new bermudagrass accessions and cultivars

AbstractBermudagrass [Cynodon dactylon (L.) Pers.] is an important forage source for ruminants in tropical and subtropical regions of the world; nevertheless, little is known about the productive and nutritional characteristics of new accessions and cultivars originating from breeding programs. Five bermudagrass cultivars (Tifton 85, Jiggs, Florida 44, Callie, and Newell) and five accessions (276, 282, 323, 286, and Missouri) were tested during the 2018 and 2019 growing seasons. Genotype × harvest interactions were detected for herbage accumulation (HA), crude protein (CP), and nitrogen yield (p < 0.05). In June, all bermudagrass genotypes showed significant variation in HA, with accession 286 being more productive than Jiggs (4.42 vs. 3.24 Mg DM ha−1 harvest−1, respectively, where DM is dry matter). In October, however, accession 323 had greater CP than Callie, accession 286, Newell, and Tifton 85, with average CP values of 155, 128, 136, and 137 g kg−1 DM, respectively. Average in vitro digestible organic matter for accession 323 (450 g kg−1 DM) was similar to that of Tifton 85 and Newell but greater than that of Missouri (393 g kg−1 DM). Genotypes displayed unique responses to all traits across harvest dates. According to the principal component analysis, the accession Missouri exhibited low productive and nutritive value properties. The accession 286 showed greater CP concentration while still productive; thus, this accession will be further examined for future release to livestock or hay producers in subtropical regions worldwide.

Independent isomeric yield ratios of fission products in the epi-cadmium neutron-induced fission of 245Cm

Abstract Independent isomeric yield ratios (IR) of 128,130,132Sb, 131,133Te, 132,134I, 135Xe and 138Cs in the epi-cadmium neutron-induced fission of 245Cm have been measured for the first time by using an off-line gamma-ray spectrometric technique. The average energy of the epi-cadmium neutron spectrum (<E n >) is 1.9 MeV. From the IR values, root mean square fragment angular momenta (J RMS) were deduced by using the spin dependent statistical model analysis. The IR and JRMS values of the fission products from the present work were compared with the literature data in the thermal neutron-induced fission of 245Cm to examine the role of excitation energy. Effect of nuclear structure on J RMS value was also examined.

Utilizing PVSyst for planning a hybrid system rooftop solar power plant at Makassar Eye Hospital

Installing rooftop Solar Power Plants (SPP) represents the most efficient solution for reducing substantial electricity consumption in office buildings and hospitals, as Makassar Eye Hospital exemplifies. The research commences by addressing concerns about electricity availability and daily usage at the hospital while evaluating the solar radiation potential. Subsequently, the development of the SPP system begins. A location assessment is conducted using various tools to gather the necessary data for SPP design. In this study, the planning phase involves the utilization of PVSyst software for the technical analysis of electrical energy generation and system performance calculations. Additionally, the economic analysis includes evaluating the initial investment costs for establishing the SPP and considering prevailing market prices for components. The feasibility of the SPP investment is determined by calculating key financial metrics, including the Payback Period (PP), Net Present Value (NPV), Internal Rate of Return (IRR), Profitability Index (PI), and Return on Investment (ROI). According to the economic analysis findings, the initial investment cost for the SPP amounts to Rp. 544.031.733. The energy production value per kilowatt-hour (kWh) stands at Rp. 1.278, resulting in a Payback Period (PP) of 13,8 years, a Net Present Value (NPV) of Rp. 138.182.638, an Internal Rate of Return (IRR) of 11.51%, and a Return on Investment (ROI) of 25.4%. These results affirm the plan's feasibility, as the IRR value surpasses the Discount Rate (8.43%).

Spatial-temporal characterization of cropland abandonment and its driving mechanisms in the Karst Plateau in Eastern Yunnan, China, 2001-2020.

The karst plateau is dominated by mountainous and hilly landforms, with low mechanization level of cropland, high difficulty of cultivation, and obvious phenomenon of cropland abandonment, which threatens regional food security. This study aims to analyze the spatial-temporal variation and its driving mechanisms of abandoned cropland in the Karst Plateau in Eastern Yunnan, China (KPEYC) between 2001 and 2020. To achieve this goal, 18 key factors from population, economic environment, cropland attributes, and farming conditions are selected. Moreover, correlation analysis, geodetector, and regression analysis methods are applied from three perspectives: temporal change, spatial distribution and spatial-temporal change. The results show that: (i) The cropland abandonment rate (CAR) in the KPEYC shows a fluctuating trend, with an average value of 9.78%, and the spatial distribution shows a pattern of "high in the center and low in the south and north". (ii) From the perspective of temporal change, gross value of agricultural production, and gross value of industrial production have the largest correlation coefficients with CAR. (iii) The explanatory power of gross tertiary industrial production, gross value of industrial production, followed by soil thickness. (iv) Gross value of agricultural production, and gross tertiary industrial production are the core driving forces for the spatial-temporal change of CAR. The higher the gross value of agricultural production and gross tertiary industrial production, the lower the CAR. elevation, soil thickness, and traffic mileage are the main driving factors for the spatial-temporal change of CAR. The study indicates that economic factors are decisive for cropland abandonment in the KPEYC. Based on the results, this study can provide decision-making support for local prevention and control of cropland abandonment, and the local community needs to promote land transfer and concentration and local urbanization according to local conditions, improve agricultural policies, improve farming conditions, etc. in order to increase farmers' enthusiasm for production, promote the rational use of cropland, and solidly push forward ecological restoration and management, optimize ecological spatial patterns, manage serious areas of rocky desertification, and appropriately alleviate the contradiction between people and land.

Impact of logistics capacity on duopoly competition: Implications for firms and consumers

AbstractPrice promotion is an effective way to capture market share, as consumer sensitivity to price is universal. Yet, consumer satisfaction with services‐such as logistics‐plays a critical role. Deep price discounts can indeed spike demand, but they can also congest systems, thus prolonging delivery times and diminishing consumer satisfaction. Despite observed significant effects of logistics capacity on consumer and firm payoffs in logistics systems in recent years, economic and operational analysis of these effects remains under explored. This study theoretically examines the influence of logistics capacity on competition between two firms using a refined Hotelling model that incorporates system congestion via a BPR‐type congestion function. Our primary findings include: First, the possibility of multiple equilibria emerges with intermediate product values, fueled by either unilateral price reductions to seize greater market share or price increases to enhance marginal benefits. Moreover, a firm with superior logistics capacity may not always set higher prices at equilibrium. Second, we show that equilibrium pricing exhibits a non‐monotonic relationship with logistics capacity and market size. Lastly, we scrutinize firms' long‐term strategic reactions to changes in logistics capacity and the implications of marginal capacity costs, symmetric or otherwise. Our findings provide the following insights. We caution that the equilibrium pricing strategy is ambiguous when the product value is not extreme because both firms are more likely to engage in random price wars. Intriguingly, while augmenting logistics capacity might elevate service satisfaction, it could paradoxically reduce firm revenue or consumer surplus. Our analysis also indicates that higher marginal capacity costs could, counter intuitively, benefit firms or consumers.

Proposing Multiregional Diagnostic Reference Levels for Common CT Angiography Examinations in Saudi Arabia.

Diagnostic reference levels (DRLs) are crucial tools for optimizing radiation exposure during different radiological examinations. This study aimed to establish preliminary DRLs for commonly performed computed tomographic angiography (CTA) examinations in Saudi Arabia. Data for three types of CTA examinations (cerebral, pulmonary, and lower-extremity) were collected from six medical cities across Saudi Arabia. Data sets related to 723 CTAs with a mean patient weight of 75 kg were analysed in detail. The DRL values were determined based on the 75th, median, and 25th CT dose index volume (CTDIvol) and dose length product (DLP) values. The established DRLs were 1221 mGy cm for cerebral CTAs, 475 mGy cm for pulmonary CTAs, and 1040 mGy cm for lower-extremity CTAs. These values were comparable to those reported in other studies. This study provides preliminary DRLs for three common CTA procedures in Saudi Arabia. The widespread implementation of a low kVp and a high level of image reconstruction (IR) presents an opportunity for further dose reduction. These findings can serve as a foundation for future nationwide DRL surveys and the optimization of CTA imaging protocols in Saudi Arabia.

Biased Voluntary Nutri-Score Labeling

Abstract Food labels are supposed to quickly inform consumers about the nutritional values of products. We provide evidence that in a system where labels are voluntary, they are systematically distorted. The probability of finding a label on a product of the category with the highest nutritional value is 51 percentage points larger than in the lowest category.

Haperforatones A-M, thirteen undescribed limonoids from Harrisonia perforata with anti-inflammatory activity

UPLC-Q-TOF-MS combined with mass defect filtering strategies were applied for the phytochemical investigation of Harrisonia perforata, leading to the isolation of thirteen undescribed limonoids named haperforatones A-M (1–13) and seventeen known compounds (14–30). Particularly, haperforatones D-E (4–5) have an unprecedented A, B, C, D-seco-6, 7-nor-C-24-limonoid skeleton, structurally stripped of the five-membered lactone ring B and formed a double bond at the C-5 and C-10 positions. Their 2D structures and relative configurations were identified using spectroscopic data. The absolute configurations of 1, 4, and 6 were established via X-ray diffraction crystallography. All 30 compounds were evaluated for anti-inflammatory potential in LPS-induced Raw 264.7 cell lines. Among those tested compounds, the most potent activity against LPS-induced NO generation was demonstrated by haperforatone F (6), with the IC50 value of inhibition NO production of 7.2 µM. Additionally, 6 could significantly inhibit IL-1β and IL-6 release and markedly downregulate the protein expression level of iNOS in the LPS-stimulated RAW264.7 cells at 10 µM. The possible mechanism of NO inhibition of 6 was also investigated using molecular docking, which revealed the interaction of compound 6 with the iNOS protein.

Mining Chinese Animation Movie Audience Concern Themes Based on BERTopic and UGC

[Objective] To explore how Chinese animated movies can effectively utilize hot topics to feed the box office and improve the competitiveness of the movies by mining hot topics of users' concern through User-Generated Content (UGC). [Methods] Based on the UGC text of Douban reviews of the Chinese animated movie "30,000 Leagues in Chang'an", we adopt the BERTopic algorithm to cluster topics based on the category-based TF-IDF (Word Frequency-Inverse Text Frequency)-weighted clustering, and introduce the semantic fine-tuning of the topics by the ChatGLM2-6B model to excavate the hot topics of users' attention. [Results] Users of the Chinese animated movie "30,000 Leagues in Chang'an" pay attention to five major topic clusters, including Chinese culture, word-of-mouth communication, poetic narrative, production technology, and the controversy of new historical facts. [Limitations] The country differences in the topic concerns of Chinese animated films were not analyzed in comparison with foreign UGC texts. [Conclusion] This study focuses on UGC text analysis to discover the social attention and evolution law of related topics. These findings provide some reference value for future Chinese animated movie production and production, box office prediction and marketing.

The effect of transport parameters on regional economic development: The case of the Ural Federal District

The transport has a special role to play in the regional socioeconomic development, which changes depending on the prevailing trends for population mobility, introduction of advanced technologies, extension of economic connections, and growth in regional production. The study explores the problem of the interface between transport and regional economy on the example of the Ural Federal District. Methodologically, it relies on the theories of spatial development and regional economics. The main method of research is correlation and regression analysis. The evidence is the socioeconomic data on transport as well as values of gross regional product of the Ural Federal District for 2010–2020 sourced from the Federal State Statistics Service of the Russian Federation. The paper develops a model for forecasting GRP. The analysis indicates the presence of the relationship between the socioeconomic metrics of the transport sector and gross regional product of the Ural Federal District. In particular, there is the correlation between the indicators “density of public roads with hard surface”, “deaths in road accidents per 100,000 population” and gross regional product of the Ural Federal District. The paper concludes about the need to develop a composite indicator for assessing the transport sector that will reflect the ongoing digital modernisation and introduction of innovations.

Evolution of Aroma Profiles in Vitis vinifera L. Marselan and Merlot from Grapes to Wines and Difference between Varieties.

The fermentation process has a significant impact on the aromatic profile of wines, particularly in relation to the difference in fermentation matrix caused by grape varieties. This study investigates the leaching and evolution patterns of aroma compounds in Vitis vinifera L. Marselan and Merlot during an industrial-scale vinification process, including the stages of cold soak, alcohol fermentation, malolactic fermentation, and one-year bottle storage. The emphasis is on the differences between the two varieties. The results indicated that most alcohols were rapidly leached during the cold soak stage. Certain C6 alcohols, terpenes, and norisoprenoids showed faster leaching rates in 'Marselan', compared to 'Merlot'. Some branched chain fatty-acid esters, such as ethyl 3-methylbutyrate, ethyl 2-methylbutyrate, and ethyl lactate, consistently increased during the fermentation and bottling stages, with faster accumulation observed in 'Marselan'. The study combines the Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA) model based on odor activity values to elucidate the accumulation of these ethyl esters during bottle storage, compensating for the reduction in fruity aroma resulting from decreased levels of (E)-β-damascenone. The 'Marselan' wine exhibited a more pronounced floral aroma due to its higher level of linalool, compared to the 'Merlot' wine. The study unveils the distinctive variation patterns of aroma compounds from grapes to wine across grape varieties. This provides a theoretical framework for the precise regulation of wine aroma and flavor, and holds significant production value.

Improving Agar Degradation Activity of Vibrio natriegens WPAGA4 via Atmospheric and Room Temperature Plasma (ARTP)

Agar oligosaccharides from the degradation of agar harbor great potential in the food and pharmaceutical industries. An agar-degrading bacterium, Vibrio natriegens WPAGA4, was isolated from the deep sea in our previous work. However, the agar-degrading activity of WPAGA4 remains to be improved for more production benefits of this strain. The aim of this study was to enhance the agar-degrading activity of WPAGA4 by using atmospheric and room temperature plasma (ARTP) mutagenesis. Three mutant strains, including T1, T2, and T3, with good genetic stability were obtained, and the agar-degrading activities of these strains increased by 136%, 141%, and 135%, respectively. The optimal temperature and pH for agar degradation were slightly changed in the mutant strains. No sequence mutation was detected in all the agarase genes of WPAGA4, including agaW3418, agaW3419, agaW3420, and agaW3472. However, ARPT mutagenesis increased the relative expression levels of agaW3418, agaW3419, and agaW3420 in the mutant strains, which could be the reason for the improvement of degradation activities in the mutant strains. Furthermore, T3 had the lowest consumption rate of agar oligosaccharide, which was 21% less than the wild-type strain. Therefore, T3 possessed a preferable production value due to its higher degrading activity and lower consumption of agar oligosaccharides. The current work enhanced the agar-degrading activity of WPAGA4 and offered strains with greater potential for agar oligosaccharide production, thereby laying the foundation for industrial applications.

Ti‐Doped ZnO Thin Films‐Based Transparent Photovoltaic for High‐Performance Broadband and Wide‐Field‐of‐View Photocommunication Window

Transparent photovoltaics (TPVs) are crucial for developing next‐generation see‐through electronics. However, TPV devices (TPVDs) require wide‐bandgap materials that are typically only responsive to short wavelength (ultraviolet, UV) lights rather than visible lights. Is it possible to improve the TPV performance by harvesting the longer wavelength lights without degradation of transparency? It may be satisfied with the function of intermediate energy states, which can utilize the lower photon energy (longer wavelength light) by a two‐step transition. To achieve this, co‐sputtered Ti‐doped ZnO (Ti:ZnO) film‐based high‐performance TPVDs have been developed. Density functional theory analysis revealed the formation of intermediate energy states due to the hybridization of O 2p and Ti 3d orbitals in the Ti:ZnO system. The Ti:ZnO‐based TPVDs show 65% average visible transparency with a power production value of 655 μW cm−2. These devices exhibit good photodetection behavior under UV to visible illuminations with high responsivity and detectivity values of 1.85 A W−1 and 2.5 × 1013 Jones, respectively. Finally, a high‐performance UV to visible broadband and wide‐field‐of‐view photocommunication system is designed based on the TPVDs to generate the fast Morse code signal. Therefore, Ti doping in ZnO provides a good way to improve the device's functionality for futuristic applications.

Production factors, regional economic development and agriculture in brazil: A spatial econometrics approach

Agriculture has a great effect on the development process of a region and production land, labor, and technology are determinant factors in its dynamism. This work carries out a spatial analysis for each production factor of Brazilian municipalities in 2006 and 2017 and intends to verify if there are patterns of association and agglomerations. This work is applied research of quantitative and exploratory nature. The Exploratory Analysis of Spatial Data (ESDA) was used to perform spatial analysis for each production factor in Brazilian municipalities in 2006 and 2017 and to check the patterns of association and agglomerations. The main agricultural activities and practice are related to exports as proposed by North. The formation of clusters verified both in the use of the factors of land, labor and technology, and in the value of agricultural production has a polarized role in the Brazilian space, as described by Perroux. This polarization and the formation of clusters expanded at certain points over time, indicating the formation of new links with neighboring municipalities (a la Hirschman). The spatial association pattern was significant in all analyzed variables, with emphasis on the non-physical technology factor, presenting the highest spatial autocorrelation coefficient in both periods analyzed.

Transcriptomics Identifies Differentially Expressed Genes Inducing Tuber Formation in Early- and Late-Maturing Potatoes.

The timing of potato tuberization is affected by potato ripeness, environmental factors, and polygene regulation. The accurate control of the transition to tuberization has both scientific and practical production value, but the key factors regulating this transition remain unclear. This study grafted an early-maturing potato variety (Favorita) scion to the late-maturing Qingshu 9 variety and demonstrated that a heterologous early-maturing scion can induce early potato formation on a late-maturing rootstock. The transcriptome of functional leaves and stolons of grafted plants was comprehensively analyzed and 593 differentially expressed genes (DEGs) were identified, including 38 transcription factors. Based on gene molecular function analysis and previous reports, we propose that PIF5, bHLH93, CBF3, ERF109, TCP19, and YABBY1 are the key DEGs that induce tuber formation in early- and late-maturing potatoes. The YABBY1 gene was subjected to functional verification. The leaf area of StYABBY1-overexpressing plants was smaller than the wild type and no potato tubercles were formed, while an RNA interference plant line showed no change in leaf area and formed tubers, indicating that StYABBY1 has a role in leaf size regulation and tuber formation.

Polish Dairy Farm Transformations and Competitiveness 20 Years after Poland's Accession to the European Union.

Poland is one of the leading milk producers in the EU, being the fifth largest after countries such as Germany, France, Italy, and the Netherlands. From Poland's accession to the European Union in 2004 up to 2022, Polish milk production experienced dynamic development. In this, there occurred a strong decline in the number of dairy farms (by -78%) and the number of cows (by -21%), an increase in dairy herd size (3.5 times) and increase in milk production (+60%) and milk yield per cow (by +62%). These were among the highest growth dynamics among the analysed countries. As a result of this significant transformation, Poland maintained an important position in milk exports, with a 31% export share in production in 2022. The scale of milk production was the basic factor determining the efficiency and competitiveness of dairy farms in Poland. Milk yield, farmland productivity, labour productivity, milk price, and the Corrected Competitiveness Index (based on labour and land opportunity costs) all showed a positive relationship with cow herd size on the farm. Milk production is highly uncompetitive for smaller farms (<15 cows). Despite substantial public support, the smaller farms, where subsidies equal up to 47% of total production value, could not earn sufficient income to cover the cost of capital, risk, and management in 2008, and even more so in 2021. This is because the farm income is too small to cover the extremely high opportunity cost of labour. The larger farms (with 30 cows and more) are competitive and responsible for the majority (~60-70%) of milk produced and delivered to the market. The most challenging from the sectoral policy point of view are medium farms (10-29 cows), whose share in production and deliveries is still important. To survive as economically viable units, these farms have to increase in scale and improve productivity. Otherwise, they will be gradually supplanted by larger farms.

Improving the approach to calculating shielding in computed tomography rooms

The study assessed the acceptability of the currently existing approach to calculating shielding in computed tomography rooms and formulated proposals for its improvement, taking into account the parameters of research in domestic medical practice. It is proposed to use the dose-length product as the main measured parameter in the new approach to calculating shielding. Typical tomograph workload values of dose-length product, typical for examinations in the Russian Federation, were assessed. Using thermoluminescent detectors, the experimental assessment of the distribution of absorbed dose in the air in a computed tomography room was carried out. The experimental results showed that the distribution of of X-ray exposure in the central plane is not isotropic. Due to the attenuation of exposure by the gantry design, “shadow” zones are observed, where the absorbed dose reduction in the air reaches 10-13 times compared to its level in the direction of couch movement. Based on the results of measurements of the distribution of absorbed dose in air, the relative scatter coefficients were calculated. The workload was determined for 7 tomographs (1 in St. Petersburg and 6 in Moscow). For each tomograph, the average weekly number of head and body examinations and the values of dose-length product for these areas were assessed, taking into account the number of multiphase examinations. The obtained workload values turned out to be one or two orders of magnitude higher than those currently used in calculating shielding. Based on the results of the study and literature data, the work proposes a new approach to calculating shielding in computed tomography rooms, based on the value of measured dose-length product during the examination and allowing to take into account the specifics of the operation of the device.