Physical Decay Research Articles

Old Age as Horror Vision or Comfort Zone in the Late Fiction of Contemporary British Novelists

Abstract Old people have always figured in literature, but the unprecedented and worldwide growth of longevity in the twentieth century has triggered new fictional approaches to the topic of aging. Thus, since the late 1980 s, an ever growing number of established British writers, reaching their own advanced years, have written on age from an insider’s perspective, creating old main characters and focusing on their mental and physical experiences. I have examined six of such novels, published between 1986 and 2019, trying to find out how the authors construct their heroes’ and heroines’ aging selves by imagining their attitudes to certain central issues like time, death, physical decay and human relationships. Of the classical formative categories (gender, class, ethnicity, etc.) gender has proved to be the most essential, especially when it comes to the perspectives on time. While the view of heroes created by male writers remains fixed on the past, often with nostalgia, sometimes with regret, the women authors’ heroines focus on their present situation with a view to the future, represented by children and grandchildren. Class turned out to be a second important category: the (uncontemplated) safe middle-class position of all protagonists appears as an indispensable precondition for the free choice of attitude to the challenges of aging.

Chemical and Biological Assay for The Degradation of Microwave Synthesized-Hyperbranched Poly (Urethane-Urea) By Local Bacterial Isolates

Ultra-fast recently Microwave-synthesized Hyperbranched Poly (urethane-urea) (MW-HBPU), is a polymer with a unique morphological structure and different applications in many fields as textile printing and coating. Because Polyurethanes (PUs) have excellent chemical and physical properties, their bio-decomposition and decay are difficult and time consuming. Therefore, MW-HBPU biodegradation by five bacterial isolates isolated from different local garbage sites has been studied. The highest activity was observed in three isolates (H1, H2 and H3), that were identified by morphology, physiology, biochemical and molecular biology (16S rRNA). Achromobacter sp. strain NRC2018, Bacillus subtilis strain NRC2018 and Bordetella petrii strain NRC2018, respectively. By determination of Carboxylesterase and acetylcholineesterase activity for the three strains. Achromobacter sp. strain NRC 2018 showed high activity give 91.2 and 526.4 U/ml for Carboxylesterase and acetylcholineesterase, respectively. The change in the characteristic functional groups reflected in the ATR-FTIR spectra of MW-HBPU after incubation with these bacteria showed attack at certain sites in the MW-HBPU structure and pointed to structural changes. SEM images clearly showed degradation in the MW-HBPU network. Additionally, a notable change in weight after incubation with isolated bacteria was also used to demonstrate the ability of these strains to effectively biodegrade MW-HBPU.

Improved Vcs determination using precise lattice QCD form factors for D→Kℓν

We provide a 0.8%-accurate determination of ${V}_{cs}$ from combining experimental results for the differential rate of $D\ensuremath{\rightarrow}K$ semileptonic decays with precise form factors that we determine from lattice QCD. This is the first time that ${V}_{cs}$ has been determined with an accuracy that allows its difference from 1 to be seen. Our lattice QCD calculation uses the highly improved staggered quark (HISQ) action for all valence quarks on gluon field configurations generated by the MILC Collaboration that include the effect of $u$, $d$, $s$, and $c$ HISQ quarks in the sea. We use eight gluon field ensembles with five values of the lattice spacing ranging from 0.15 fm to 0.045 fm and include results with physical $u/d$ quarks for the first time. Our calculated form factors cover the full ${q}^{2}$ range of the physical decay process and enable a Standard Model test of the shape of the differential decay rate as well as the determination of ${V}_{cs}$ from a correlated weighted average over ${q}^{2}$ bins. We obtain $|{V}_{cs}|=0.9663(53{)}_{\mathrm{latt}}(39{)}_{\mathrm{exp}}(19{)}_{{\ensuremath{\eta}}_{\mathrm{EW}}}(40{)}_{\mathrm{EM}}$, where the uncertainties come from lattice QCD, experiment, short-distance electroweak, and electromagnetic corrections, respectively. This last uncertainty, neglected for $D\ensuremath{\rightarrow}K\ensuremath{\ell}\ensuremath{\nu}$ hitherto, now needs attention if the uncertainty on ${V}_{cs}$ is to be reduced further. We also determine ${V}_{cs}$ values in good agreement using the measured total branching fraction and the rates extrapolated to ${q}^{2}=0$. Our form factors enable tests of lepton flavor universality violation. We find the ratio of branching fractions for ${D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}$ with $\ensuremath{\mu}$ and $e$ in the final state to be ${R}_{\ensuremath{\mu}/e}=0.9779(2{)}_{\mathrm{latt}}(50{)}_{\mathrm{EM}}$ in the Standard Model, with the uncertainty dominated by that from electromagnetic corrections.

Time as a Key Factor in the Preservation of Built Heritage

ABSTRACT Though often not considered as a concept in its own right, time can be regarded as a key factor for the preservation of the built heritage. Time can be taken into account as an implicit and discriminating factor, projecting itself onto the building and imbuing three aspects of its conservation: there is a relationship between the historical evolution of the concept of restoration and a change in the perception of time; the relationship between sense of time and the development of the building through time is likewise significant; thus a temporal approach to ancient buildings leads to a pluralistic attitude toward their physical decay. For example, assuming time to be a dimension of a building alters the concepts of both entirety and decay. An increasingly nuanced contemporary perception of time is supposed to enhance critical thinking about preservation, but this requires a more clearly articulated idea of intervention, and a many-sided approach that combines reason and emotions. Deliberately including a recognition of the passage of time within a preservation programme requires significant effort to reconcile technical aspects and perception, enhancing the idea of conservation interventions as never-ending interpretation, and suggesting further ways of appreciating built heritage. The discussion is centred around attitudes to monuments in Italy but the approach is relevant internationally.

Current State of Targeted Radiometal-Based Constructs for the Detection and Treatment of Disease in the Brain.

The continual development of radiopharmaceutical agents for the field of nuclear medicine is integral to promoting the necessity of personalized medicine. One way to greatly expand the selection of radiopharmaceuticals available is to broaden the range of radionuclides employed in such agents. Widening the scope of development to include radiometals with their variety of physical decay characteristics and chemical properties opens up a myriad of possibilities for new actively targeted molecules and bioconjugates. This is especially true to further advance the imaging and treatment of disease in the brain. Over the past few decades, imaging of disease in the brain has heavily relied on agents which exploit metabolic uptake. However, through utilizing the broad range of physical characteristics that radiometals offer, the ability to target other processes has become more available. The varied chemistries of radiometals also allows for them to incorporated into specifically designed diverse constructs. A major limitation to efficient treatment of disease in the brain is the ability for relevant agents to penetrate the blood-brain barrier. Thus, along with efficient disease targeting, there must be intentional thought put into overcoming this challenge. Here, we review the current field of radiometal-based agents aimed at either imaging or therapy of brain disease that have been evaluated through at least in vivo studies.

Suitability of specific soft tissue swabs for the forensic identification of highly decomposed bodies

When decomposition of a recovered body is fairly advanced, identification based on common morphologic features is often impossible. In these cases, short tandem repeat (STR) marker genotyping has established itself as a convenient and reliable alternative. However, at very progressed stages of decomposition, postmortem tissue putrefaction processes can decrease DNA yields considerably. Hence, not all types of tissue are equally suitable for successful STR marker-based postmortem identification. Bone or dental material is often analysed in corpses with advanced decompositional changes. However, processing of these materials is very elaborate and time and resource consuming. We have therefore focused on the suitableness of various types of soft tissue swabs, where DNA extraction is easier and faster. By sampling 28 bodies at various stages of decomposition, we evaluated the suitability of different tissues for genotyping at varying degrees of physical decay. This was achieved by a systematic classification of the sampled bodies by morphological scoring and subsequent analysis of multiple tissue swabs of the aortic wall, urinary bladder wall, brain, liver, oral mucosa and skeletal muscle. In summary, we found variable degrees of suitability of different types of soft tissue swabs for DNA-based identification. Swabs of the aortic wall, the urinary bladder wall and brain tissue yielded the best results — in descending order — even at advanced levels of decay.

Feasibility of Using Recycled Burnt Clay Brick Waste in Cement-Based Mortar: Mechanical Properties, Durability, and Residual Strength After Exposure to Elevated Temperatures

This paper investigates the possibility of utilizing burnt clay brick waste (CBW) as a partial replacement for natural sand (NS). The natural sand was replaced with CBW at five levels: 0%, 25%, 50%, 75%, and 100%. The physical properties, mechanical strength, shrinkage, porosity, and decay of compressive strength due to elevated temperatures (after exposure to 20, 250, 400, and 600 °C) were performed. The results show that the workability and dry density of mortar decrease as the CBW content increases. The mechanical strength of the mortar increases up to 50% replacement level of NS with CBW. The increase represents 17–25% for compression, 25–31% for tensile, and 5–31% for flexural strength relative to the reference mix (100% NS) at all curing ages (7, 14, 28, and 60 days). Furthermore, results show that the shrinkage increases with an increase in the content of CBW. A decreasing trend of porosity was observed for the mortar made with up to 50% CBW, which is in good agreement with the mechanical strength of mortar. Nevertheless, the residual compressive strength of mortar decreases for all mixes at elevated temperatures, and it was more pronounced for the higher temperatures. This study demonstrates that up to 50% of CBW can be used as fine aggregate in mortar since it enhances the mechanical and durability performances.

Decay amplitudes to three hadrons from finite-volume matrix elements

We derive relations between finite-volume matrix elements and infinite-volume decay amplitudes, for processes with three spinless, degenerate and either identical or non-identical particles in the final state. This generalizes the Lellouch-Lüscher relation for two-particle decays and provides a strategy for extracting three-hadron decay amplitudes using lattice QCD. Unlike for two particles, even in the simplest approximation, one must solve integral equations to obtain the physical decay amplitude, a consequence of the nontrivial finite-state interactions. We first derive the result in a simplified theory with three identical particles, and then present the generalizations needed to study phenomenologically relevant three-pion decays. The specific processes we discuss are the CP-violating K → 3π weak decay, the isospin-breaking η → 3π QCD transition, and the electromagnetic γ* → 3π amplitudes that enter the calculation of the hadronic vacuum polarization contribution to muonic g − 2.

The geographic distribution of retail tobacco outlets in Yogyakarta, Indonesia.

Tobacco smoking prevalence in Indonesia is among the highest in the world. Research worldwide identifies that physical access to tobacco through retail outlets is related to increased tobacco smoking. Tobacco outlet density is very high in many Indonesian cities, so tobacco access may contribute to the high prevalence of tobacco use in that country. The aim of this study was to examine distributions of tobacco outlets in one Indonesian city, Yogyakarta, in relation to social and physical environmental conditions. For this cross-sectional ecological study, we virtually audited randomly selected street segments (n = 1099) using Google Street View. The outcome of interest was a count of tobacco advertising banners (indicating the presence of retail outlets). Exposures were physical environmental conditions (scales of main roads, physical decay, presence of schools, mosques, churches) and social conditions measured at the neighbourhood level (concentrated disadvantage, age composition, population density). Tobacco banners were present on 36.4% of sampled street segments, including 55 (37%) of 147 streets with schools; a total of 1381 banners were identified. Multilevel negative binomial regression models for street segments nested within neighbourhoods found the prevalence of tobacco banners per 100 m was lower near schools (RR = 0.66, 95% CI 0.45, 0.97) and was not associated with other exposure measures. Retail tobacco outlets are ubiquitous in Yogyakarta. Although they are relatively less prevalent on streets with schools, the high absolute values and wide spatial distribution means all residents of Yogyakarta are exposed to tobacco outlets.

Echoes of the Heart: Henry James’s Evocation of Edgar Allan Poe in “The Aspern Papers”

This essay re-examines Henry James’s complex relationship with Edgar Allan Poe by focusing on the echoes of one of Poe’s most celebrated tales, “The Tell-Tale Heart” (1843), that later reverberate in James’s “The Aspern Papers” (1888). It highlights the similarities, both in mindset and behavior, between the two stories’ devious and deranged first-person narrators, whose actions result in the death of a fellow human being. It further discusses the narrators’ fear and refusal of their own mortality, which finds expression in their hostility, and barely contained revulsion against a man (in “The Tell-Tale Heart”) and a woman (in “The Aspern Papers”), whose principal defining traits are old age and physical decay.

Changes in environmental radiation levels in Katsushika Ward, Tokyo after the Fukushima Daiichi Nuclear Power Plant accident

Katsushika Ward, located in northeastern Tokyo, had the highest deposition in Tokyo of artificial radionuclides after the Fukushima Daiichi Nuclear Power Plant accident. A car-borne survey for measuring absorbed dose rate in air was carried out in the ward in each of the years 2015–2020. The average dose rates measured in 2015–2018 decreased every year but percentage reductions were smaller after 2018 due to the decrease in 134Cs amount; this radionuclide decays with a half-life of 2.065 years. Its ecological half-life was estimated to be 1.6 y and that value was shorter than the physical decay life (3.2 y).

Notes About Crushing Sand from Bituminous Schist

Abstract People have used sand and stone for foundations for thousands of years. Significant refinement of the production and use of aggregate occurred during the Roman Empire, which used aggregate to build its vast network of roads and aqueducts. The invention of concrete, which was essential to architecture utilizing arches, created an immediate, permanent demand for construction aggregates. Construction aggregate, or simply “aggregate”, is a broad category of coarse to medium grained particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates. Aggregates are the most mined materials in the world. Aggregates are a component of composite materials such as concrete and asphalt concrete; the aggregate serves as reinforcement to add strength to the overall composite material. Due to the relatively high hydraulic conductivity value as compared to most soils, aggregates are widely used in drainage applications such as foundation and French drains, septic drain fields, retaining wall drains, and roadside edge drains. Aggregates are also used as base material under foundations, roads, and railroads. In other words, aggregates are used as a stable foundation or road/rail base with predictable, uniform properties (e.g. to help prevent differential settling under the road or building), or as a low-cost extender that binds with more expensive cement or asphalt to form concrete. Preferred bituminous aggregate sizes for road construction are given in EN 13043 as d/D (where the range shows the smallest and largest square mesh grating that the particles can pass). The same classification sizing is used for larger armour stone sizes in EN 13383, EN 12620 for concrete aggregate, EN 13242 for base layers of road construction and EN 13450 for railway ballast. Aggregates themselves can be recycled as aggregates. Unlike deposits of sand and gravel or stone suitable for crushing into aggregate, which can be anywhere and may require overburden removal and/or blasting, “deposits” of recyclable aggregate tend to be concentrated near urban areas, and production from them cannot be raised or lowered to meet demand for aggregates. Supply of recycled aggregate depends on physical decay of structures and their demolition. The recycling plant can be fixed or mobile; the smaller capacity mobile plant works best for asphalt-aggregate recycling. The material being recycled is usually highly variable in quality and properties.

Caesium-137 in mountain flora with emphasis on reindeer's diet – Spatial and temporal trends

The present study summarizes three decades of studies on 137Cs transfer to various species of lichens, graminoids, herbs and woody plants across a ~3000 km2 area used as mountain pasture for reindeer and other ruminants. The investigation comprised of field studies covering the period 2011–2016, and a compilation of studies and data for the preceding period (1986–2010). Altogether, more than 700 individual vegetation samples were considered. For lichens, relatively fast decrease in contamination levels was observed during the first decade after the Chernobyl fallout (ecological half-time of about 3 years). For later years there seems to be a continuous re-contamination which results in a “steady state” where time-trends are mainly governed by physical decay of 137Cs. For green plants, decline in transfer factors (TF) (i.e. the ratio between activity concentration in vegetation and activity density in soil) during the period 1986–2012 was not as pronounced as for lichens: Some species showed significant decrease with time, while others did not. 25–30 years after the Chernobyl accident, 137Cs levels in lichens and green plants were significantly dependent on the levels in soil (R2 between 0.53 and 0.57), but there were also some significant differences in transfer between sampling sites. Moreover, marked variability in TFs was found between different plant species growing at the same site, whereas such differences were not found for reindeer lichens.

Athermal jamming vs. glassy dynamics for particles with exponentially decaying repulsive pair interaction potentials with a cutoff

We study athermal jamming as well as the thermal glassy dynamics in systems composed of spheres that interact according to repulsive interactions that exponentially decay as a function of distance. As usual, a cutoff is employed in the simulations. While the athermal jamming transition that is determined by trying to remove overlaps is found to depend on the arbitrary and therefore unphysical choice of the cutoff, we do not find any athermal jamming transition or crossover that only relies on the physical decay length. In contrast, the glassy dynamics mainly depends on the decay length. Our findings constitute another demonstration of the fact that the athermal jamming transition is not related to thermal glassy dynamics. In addition, we argue that interactions without sharp physical cutoff should be considered more often as a model system in jamming. The reevaluation of widely used theoretical approaches or methods of analysis in the field of jamming and the task to change them such that they do not depend on unphysical cutoffs will lead to deeper insights into the nature of athermal and thermal jamming.

Life-cycle assessment of climate change impact on time-dependent carbon-footprint of asphalt pavement

This study aims to quantify life-cycle carbon footprint of asphalt pavement due to warming temperatures under climate change scenario.Pavement Mechanistic-Empirical (ME) Design Method was used to simulate long-term pavement performance with historic and projected temperature inputs. Life-cycle assessment (LCA) was conducted to calculate CO2emissions in pavement life cycle including phases of raw materials, plant production, transportation, field construction, traffic delay, and use. In particular, time-dependency of CO2emission was considered with physical decay to increase the accuracy in estimating cumulative radiative forcing. It was found that warming temperatures would lead to faster structural deterioration of pavement, resulting in earlier or more frequent overlay treatments. Pavement rehabilitation treatments generate more CO2 emission in material and construction related stages but cause the reduction of CO2 emission in pavement use phase. The LCA results show that climate change causes greater CO2 emission abundance over the years during the study period.

Bagging Organic Peaches Reduces Physical Injuries and Storage Decay with Minimal Effects on Fruit Quality

Fruit bagging is an acceptable cultural practice for organic production that provides a physical barrier to protect fruit. It can reduce pest and pathogen injury for a variety of fruit crops, but quality attributes have been inconsistent for peach [Prunus persica (L.) Batsch] and other bagged fruit. A 2-year experiment on a U.S. Department of Agriculture (USDA) organic-certified peach orchard in central Florida was conducted to analyze the effects of a commercially available paper bag designed for fruit protection and cardinal quadrant (north, south, east, and west sides) of the tree canopy on low-chill peach ‘TropicBeauty’ fruit quality. Protective bags appeared to delay fruit maturity. Flesh firmness and chlorophyll concentration of bagged fruit were 31% and 27% greater than unbagged fruit, respectively. Bagged fruit were protected as demonstrated with a reduction in mechanical injury by 95%, fruit fly injury by 450%, and scab-like lesions by 810%. Bagging reduced fruit brown rot (Monilinia fructicola) at harvest and 7 days after harvest; unbagged fruit were 2 and 3.5 times more likely to have rot at harvest and 7 days after harvest, respectively. Fruit bags did not affect yield, fruit size, total soluble solids, titratable acidity, pH, peel lightness, peel hue angle, or flesh color. Overall, canopy cardinal quadrant location had minimal effect on fruit quality or fruit injury. These results demonstrate that bagging peach fruit protects against various pests and diseases but has minimal effects on fruit quality. Broad adoption of this technology is highly dependent on available labor, market demands, and profitability but may be suitable for producers using direct-to-consumer market channels.

Оценка радиоэкологической обстановки на территориях аварийного чернобыльского следа в России (1986-2020)

The current environmental situation in areas located in the “Chernobyl footprint” in Russia is con-sidered in the paper. Radiation contamination in different parts of the “footprint” varies from the maximum level in the exclusion zones to the level close to the background in areas with low level of radioactive contamination. Environmental monitoring data and calculated density of soil con-tamination with radionuclides in the vicinities of residential areas in Bryansk, Kaluga, Tula, Orel and Novgorod regions were used as reference data for assessment of radiation dose rates and ecological risks for the reference biological species: the elk (Alces alces), red-backed mouse (Myodes glareolus), the Archangel fir (Pinus sylvestris), brandling (Lumbricus terrestris), the pike (Esox lucius), and the fresh-water soldier (Stratiotes aloides). The integrated contamination index, that is the sum of ratios of registered radionuclides contamination density to the reference levels, was used as the indicator of territory radioecological safety. The calculation was made in accord-ance with the Roshydromet Recommendations R-52.18.853-2016. The highest doses to the biota and ecological risks were registered in 1986. Radiation dose rates to some vertebrates in the most contaminated districts of the Bryansk region in May 1986 exceeded ecologically safe radiation level of 1 mGy/day. Doses to reference biological species inhabited outside exclusion zones within the period of May-December 1986 were lower than the radioecological safety level. After decay of 131I and other short-lived radionuclides 137Cs became the basic contributor to the biota dose. Radiation dose rate to the terrestrials and radio-ecological safety index gradually decreased due to radionuclides physical decay over the period of 1986-2020. Current radiation doses to the terrestrials inhabited the most contaminated districts were, on average, one order below the safe radiation dose to the vertebrates, two orders below the safety radiation level to the Archangel fir and three orders be-low the safety radiation dose to the soil invertebrates. Current radiation dose rates to inhabitants of the lake of Kozhanovskoe, one of the most contaminated areas due to the radioactive fallout, current radiation dose rates to the lake fish were two orders below the safe level, radiation dose rates to algae were three orders below the safety level, however, they still are above the back-ground level. Current indices of integrated contamination in areas of the Chernobyl radioactive “footprint” are inhomogeneous. Current indices of integrated contamination in the majority of contaminates areas are dozens times and the indices in low radiation contaminated areas are hundreds times lower than ecological safety level. The highest indices occur in a number of dis-tricts of Bryansk region but they are lower than ecological safety level, however in some sites in exclusion zones the indices exceed the ecological safety level. These sites are unique natural testing grounds for radio-ecological research and monitoring of the environment and radiation protection development. In this connection it is recommended to continue long term research and development of radiological protection of the environment.

The Repatriation of European Nationals from Syria as Contested before Domestic Courts in Belgium and Beyond

Since the physical decay of Islamic State and other radical Islamic groups in Syria, a considerable number of European nationals who are held captive in Syria have expressed their will to return to their home country. Some of them have initiated cases before the national courts of their home country to enforce their repatriation. This paper primarily analyses relevant Belgian cases, revolving around human rights law and consular law. Second, it puts these cases in a comparative perspective to cases in other European states, namely the Netherlands, Germany and France. The paper finds that in all four legal systems, relevant cases were dealt with differently. Overall, it appears that in states where a constitutional duty or civil law standard of care for the state vis-a-vis its citizens is more entrenched, such as in Germany and the Netherlands, the legal framework to deal with nationals abroad in conflict areas is more straightforward. In states like Belgium and France, where this is less entrenched, cases have wavered between varying legal bases; from international to national, and human rights to consular law and criminal law. This has resulted in a standstill at the national level, with courts looking at the European Court of Human Rights to offer a way out.

Physical performance development in a female national team soccer program

ObjectivesSignificant resources are invested in maximizing player performance without extensive knowledge of the athletic progression of elite female soccer players during their career. The aim of the current study was therefore to investigate the change in physical performance characteristics in 12- to 34-year-old female soccer players in a national team program. DesignMixed-longitudinal study. MethodsPhysical performance was assessed across five years and 657 testing occasions (n = 143) using anthropometrics, 40 m sprint (10 m split), broad jump, countermovement jump, squat jump, and 30-15 intermittent fitness test (IFT). ResultsUsing a Gaussian mixture model, Youth and Senior groups were bifurcated at approximately 23 years old. Subsequent linear mixed models for each group and variable identified significant improvements in the Youth group in maximal speed (30−40 m split), broad jump, countermovement jump, and final velocity30−15IFT (p ≤ 0.002), and a decrease in squat jump height with increasing age (p = 0.04). The Senior group recorded slower 10 m sprint time and a decrease in squat jump height with increasing age (p < 0.001). Body mass increased from 12 to 34 years old (Youth and Senior: p ≤ 0.001). The Youth group significantly differed in the rate of change compared to the Senior group in body mass, 10 m sprint time, countermovement jump, squat jump, and final velocity30-15IFT (p ≤ 0.001). ConclusionsThis information can be used to identify average rates of physical performance improvement and decay to help guide optimal physical training and maximize the longevity of a female soccer players’ career.

Retrospective analysis of the radiation situation in the territory of the Oryol region

The article considers the radiation situation in the Oryol region 33 years after the accident at the Chernobyl nuclear power plant. Since 1998, certification has made it possible to assess the main indicators of the radiation situation in the region and conduct a comparative analysis, evaluate the doses of the population from all the main sources and the effects of the radiation factor on public health, and determine the most significant directions for reducing the doses of the population. The contribution of man-made sources to the collective dose to the population of the Oryol region in 2017 was 0.73% according to radiation-hygienic certification, which is 3 times higher than in Russia (0.24%). This is primarily due to radioactive contamination of a part of the region after the Chernobyl accident. The Oryol region is one of fourteen oblasts of the Russian Federation affected by the accident at the Chernobyl nuclear power plant. As a result of this disaster, 22 out of 24 districts of the Oryol Oblast (about 40% of the oblast’s territory) were exposed to radioactive contamination to one degree or another. Differences in precipitation led to the formation of extremely spotted pollution in the Oryol region. 1243 people from the Oryol region took part in the liquidation of the Chernobyl accident. 43% of them became disabled 1, 2 and 3 groups, 115 people (9%) died within 14 years after these events. In the Oryol region, the radiation environment remains stable. The radiation background is between 0.12 and 0.19iSv/h, which corresponds to the values characteristic of the Oryol region before the Chernobyl accident. Comparison of radiation doses due to additional radiation for the 1st and 33rd years after the accident showed a 51-fold decrease due to the physical decay of long-lived radioisotopes and short-lived radionuclides, as well as their burial in the soil.