Acceptable Contamination Levels Research Articles

Real-Time Self-Assembly of Stereomicroscopically Visible Artificial Constructions in Incubated Specimens of mRNA Products Mainly from Pfizer and Moderna: A Comprehensive Longitudinal Study

Observable real-time injuries at the cellular level in recipients of the “safe and effective” COVID-19 injectables are documented here for the first time with the presentation of a comprehensive description and analysis of observed phenomena. The global administration of these often-mandated products from late 2020 triggered a plethora of independent research studies of the modified RNA injectable gene therapies, most notably those manufactured by Pfizer and Moderna. Analyses reported here consist of precise laboratory “bench science” aiming to understand why serious debilitating, prolonged injuries (and many deaths) occurred increasingly without any measurable protective effect from the aggressively, marketed products. The contents of COVID-19 injectables were examined under a stereomicroscope at up to 400X magnification. Carefully preserved specimens were cultured in a range of distinct media to observe immediate and long-term cause-and-effect relationships between the injectables and living cells under carefully controlled conditions. From such research, reasonable inferences can be drawn about observed injuries worldwide that have occurred since the injectables were pressed upon billions of individuals. In addition to cellular toxicity, our findings reveal numerous — on the order of 3~4 x 106 per milliliter of the injectable — visible artificial self-assembling entities ranging from about 1 to 100 µm, or greater, of many different shapes. There were animated worm-like entities, discs, chains, spirals, tubes, right-angle structures containing other artificial entities within them, and so forth. All these are exceedingly beyond any expected and acceptable levels of contamination of the COVID-19 injectables, and incubation studies revealed the progressive self-assembly of many artifactual structures. As time progressed during incubation, simple one- and two-dimensional structures over two or three weeks became more complex in shape and size developing into stereoscopically visible entities in three-dimensions. They resembled carbon nanotube filaments, ribbons, and tapes, some appearing as transparent, thin, flat membranes, and others as three-dimensional spirals, and beaded chains. Some of these seemed to appear and then disappear over time. Our observations suggest the presence of some kind of nanotechnology in the COVID-19 injectables.

Enlightening the Universe behind the Milky Way bulge

Context. The location of the Solar System complicates the detection extragalactic sources beyond the Milky Way plane. The optical observations are hampered in the so-called zone of avoidance (ZOA), where stellar crowding and Galactic absorption are severe. Observations at longer wavelengths are needed in order to discover new background galaxies and complete the census in the ZOA. Aims. The goal of this work is to identify galaxies behind the Milky Way bulge using near-infrared (NIR) data from the VISTA Variables in Vía Láctea (VVV) survey. Methods. To this end, we made use of different VISTA Science Archive (VSA) tools in order to extract relevant information from more than 32 billion catalogued sources in the VVV bulge region. We find that initial photometric restriction on sources from the VSA vvvSource table combined with restrictions on star–galaxy separation parameters obtained from Source Extractor is a successful strategy for achieving acceptable levels of contamination (60%) and high completeness (75%) in the construction of a galaxy target sample. To remove contaminating Galactic sources from the initial target sample, our methodology also incorporates a visual inspection of false-colour RGB images, a crucial quality control carried out following a specifically defined procedure. Results. Under this methodology, we find 14 480 galaxy candidates in the VVV bulge region, making this sample the largest catalogue to date in the ZOA. Moreover, these new sources provide a fresh picture of the Universe hidden behind the curtain of stars, dust, and gas in the unexplored Milky Way bulge region. Conclusions. The results from this work further demonstrate the potential of the VVV/VVVX survey to find and study a large number of galaxies and extragalactic structures obscured by the Milky Way, expanding our knowledge of the Universe in this challenging and impressive region of the sky.

Ethylene oxide: methodological approaches to the determination of residues in food products (literature review)

Introduction. Ethylene oxide is a prohibited fumigant in the Russian Federation and the states of the European Union (EU), however, the substance is used in a number of other countries to disinfect food before they are sold, so there is a risk of such products entering the Russian market, which can lead to negative consequences for public health. The residues of the fumigant in consumed products can cause neurological disorders and the development of cancer in humans. In addition, the presence of 2-chloroethanol in foodstuffs, the main transformation product of ethylene oxide, which is formed during the interaction of the fumigant with the matrix, is of concern. 
 Material and methods. The analysis of domestic and foreign databases and regulatory legal acts on the regulation of the dangers of ethylene oxide and 2-chloroethanol was carried out.
 Results. The toxicological characterization of ethylene oxide and 2-chloroethanol shows the need to establish acceptable levels of contaminants in food, and, as a result, to create a simple and effective analytical control method. 
 Limitations.The study is limited to a review of open literature sources in describing the toxicological characterization and methods of analysis of ethylene oxide in food products.
 Conclusion. The analysis of open literature sources has shown the need for scientific substantiation of hygienic standards and the development of a method for controlling the content of ethylene oxide and 2-chloroethanol in food products.

Increasing efficiency of irrigation reclamation in potato and soybean agrocenoses using sludge

The purpose of the study was to assess effect of different doses of wastewater sludge on productivity of irrigation water use by agrocenoses of potatoes (Zhukovsky rannii) and soybeans (VNIIOZ 31), on their yield, as well as the index of soil contamination and seed production. Agrometeorological conditions of the periods of vegetation experiments are characterized as dry with hydrothermal coefficient value of no more than 0.39. Considering the current climatic conditions, regulations for watering potatoes and soybeans were drawn up. It was established that application of WWS in doses of 20, 40 and 60 tha-1 had different effects on crops total water consumption. In potato crops, irrigation rate varied from 2590 m3ha-1 in the control to 1850 m3ha-1 in WWS60 variant, and in soybean crops, it varied from 3700 in the control to 2960 m3ha-1 in WWS60 variant. At the same time, amount of irrigation water to obtain a ton of potato and soybean yield in the control averaged 124.5 and 1298.2 m3t-1, respectively, against 118.372.8 and 1213.1886.2 m3t-1 for variants WWS20, WWS40 and WWS60, which corresponded to increase in water use productivity from 5.0 to 41.5 % and from 6.6 to 31.7 %, respectively. Laboratory studies of soil samples of the arable layer showed that pollution index in relation to heavy metals Cd, Pb, Zn, Cu varies from 2.54 in variant WWS20 to 4.04 in variant WWS60, which indicates the absence of soil contamination. Evaluation of potato tubers for values of starch, dry matter, nitrates and heavy metals demonstrates sufficiently high quality and acceptable level of contamination of the seeds.

Bacterial pathogens associated with eyeglasses and risks of infection: A cross-sectional study in South-West Nigeria

Ocular infections have been associated with bacterial contamination of eyeglasses. This study assessed bacterial contaminants associated with the eyeglasses of the staff and students of Babcock University, Ilishan-Remo, Ogun State, Nigeria. A total of 100 participants comprising 33 males and 67 females (aged 16-76 years) were recruited for the study after obtained the written informed consents. A structured questionnaire was used to collect the demographic and clinical information. A total of 100 eyeglasses were examined for bacterial contamination using standard bacteriological methods. A one–way analysis of variance (ANOVA) and Tukey–Kramer multiple comparisons test were used to determine the differences between the bacterial loads among the eyeglasses of study participants. We found that the percentage of eyeglass lenses with unacceptable levels of contamination (105CFU/mL) and acceptable levels of contamination were 19% and 46%, respectively. The percentages of eyeglass handles with unacceptable and accepted level of contamination were 49% and 7%, respectively. Most of the isolated bacteria were sensitive to the tested antibiotics. Risk factors associated with bacterial contamination of eyeglasses were exposure to dusty environment, irregular cleaning, and poor compliance with eyeglass care guidelines. Our study further underscores the claim that eyes glasses may serve as potential vehicles for bacteria capable of causing ocular infections.

Effects of impurities in the cathode airflow on proton exchange membrane fuel cell stacks

AbstractFuel cells for mobile applications obtain their oxygen from the ambient air in road traffic. This air has contaminations of various impurities that can have negative effects on the lifetime of fuel cell systems in vehicles. The identified most relevant contaminants are toluene, nitrogen dioxide, ammonia, and sulfur dioxide. A modified test bench enables different dosages of the above‐mentioned pollutant gas concentrations on the cathode side. We examined influences both in static cycles for quasi‐steady states and in dynamic cycles for rapid load changes to examine reversible and irreversible degradation effects. We showed that the harmful cathode gases examined could lead to a shortening of the service life of fuel cells. Whereas this is well known for higher concentrations of pollutants, this contribution provides data in the sub‐ppm range – including the effects of gas mixtures – for which literature data is still limited.Additionally, a physical fuel cell model is developed to analyze the effects of various contaminants. The overall intention is to determine acceptable contamination levels and thereby increase the lifetime of fuel cells with the help of simulations. The presented model allows for the computation of cell voltage dependent on cathode side media conditions.

Assessing decontamination practices at a medical microbiology research laboratory

To our knowledge, this is the first study to conduct an objective assessment of the routine decontamination practices at a medical microbiology research laboratory (MRL) a year after a biosafety training was provided to all laboratory staff. Between March 28th and June 28th, 2021, unobtrusive observations were carried out to identify-three high-touch surfaces at the MRL during different working hours. Swabbing was used to evaluate the effectiveness of the disinfectant used in the laboratory. All three high-touch surfaces were sampled before and after decontamination with 200 ppm of 5 % sodium hypochlorite (household bleach) to quantify the microbial load and identify the types of organisms residing on the laboratory surfaces. A higher concentration (500 ppm) of 5 % sodium hypochlorite was employed after refresher training was provided to housekeeping staff, and resampling of the three surfaces was carried out during a 4-week follow-up period using the same procedure. The three high-touch surfaces identified were the two sides of the workbench (22 %–24 %) and the front surface of one incubator (14 %). Anthracoid bacilli and Staphylococcus aureus were the most commonly found organisms on laboratory surfaces pre-intervention (100 % and 89 %, respectively) and post-intervention (56 % and 44 %, respectively). Other microorganisms detected included Salmonella spp. (27.7 %), Proteus spp. (5.6 %), Escherichia coli (5.6 %), and Klebsiella spp. (33.3 %). Employing a higher concentration (500 ppm) of sodium hypochlorite significantly (p ≤ 0.000) reduced the total aerobic colony count from an average of 15–250 cfu/cm2 to 10–60 cfu/cm2. This study demonstrated suboptimal decontamination practices at the MRL and the need to apply a higher concentration (500 ppm) of sodium hypochlorite to reduce the overall microbial load. It also demonstrated the importance of quantitative assessment to monitor decontamination practices and ensure staff compliance. More studies are needed to identify bacterial communities within the laboratory, which will help provide guidance regarding the types, proper concentrations, and appropriateness of the in -use disinfectants. Furthermore, large-scale studies on the acceptable level of residual contamination following any decontamination process are urgently recommended.

245.2: Evaluation of Methods to Obtain Peripheral Blood Mononuclear Cells From Deceased Donors Adjacent to Organ Procurement for Tolerance-Induction Protocols

Regulatory cell therapies have shown promise in tolerance-induction protocols in living donor organ transplantation. These protocols should be pursed in deceased-donor transplantation. Donor peripheral mononuclear cells (PBMCs) are an optimal source of donor antigens for the induction of donor-specific regulatory cells that are more effective than antigen non-specific regulatory cells. During the development of a regulatory cell tolerance induction protocol with organs from deceased donors, we compared three methods of obtaining PBMCs from deceased donors focusing on: cell yield, viability, and contamination of unwanted cell types. PBMC procurement methods: During organ procurement at the time of cold perfusion, blood was collected from the vena cava and placed into a 10-liter blood collection bag, and thereafter transported to Karolinska University Hospital, where leukapheresis was performed (BCL) n=7. Blood was collected via the vena cava into blood donation bags before cold perfusion. The bags underwent buffy coat separation and thereafter automated leukocyte isolation using SEPAX (BCS) n=2.To collect PBMCs, leukapheresis was performed via a central dialysis catheter on deceased donors in the ICU prior to the organ procurement procedure (LEU) n=9. Our results show that all methods were safe in relation to the intended organ procurement procedure. LEU is a feasible method to obtain PBMC from deceased donors. LEU tend to have higher yield of donor PBMC/kg compared to BCS and BCL and acceptable level of granulocyte contamination compared to BCS. Further investigations including the quality of the cell products that was manufactured with PBMCs from these methods will be needed to determine which approach is the most suitable for tolerance induction protocols.

Pastille Isomalt and Erythritol Based Product Enriched with Biologically Active Substances of Black Currant

The development of new functional food products ensuring the human health preservation and strength is an important growth direction of the food industry. The research aims at developing a recipe and production technology of sugar-free pastille confectionery (marshmallows) enriched with plant biologically active substances of black currant for patients with diabetes mellitus type 2. A man replaced sugar in confectionery with erythritol and isomalt mixture; and examined a sample of marshmallows with 100 % sugar replacement in comparison with traditional marshmallows on sugar using apple pectin. The researchers determined the optimal ratio of erythritol and isomalt sweeteners – 7 : 3. They developed the pastille product manufacture technology. There was an increase in the antioxidant activity indicator from 0.716 mmol-eq./dm3 to 2.269 mmol-eq./ dm3 when adding a black currant juice. The vitamin C content increased from 0.043 % to 0.857 %. Despite the increased humidity (19.6 %), the experimental marshmallow sample had good organoleptic indicators (average score – 4.39). Acceptable levels of microbiological contamination of a marshmallow sample based on sweeteners are maintained for 48 hours. The developed recipe will expand the confectionery products range for diabetic nutrition.

СПОСОБ ОПРЕДЕЛЕНИЯ ОПТИМАЛЬНОЙ ДЛИНЫ ТРИЕРНОГО ЦИЛИНДРА

. It is known that agricultural enterprises are equipped with grain cleaning units of the ZAV40 and KZS-40 types. It is known that in 90% of cases trier blocks of units are taken out of service, since they do not provide the required quality of grain cleaning and are unreliable in operation - technological failures occur due to blockages of cellular cylinders. This problem can be partially solved by using indented blocks with the optimal length of the indented cylinder. This will lead to a significant reduction in the loss of clean grain to waste while maintaining an acceptable level of residual contamination and increasing reliability. A mathematical model has been developed for the operation of the grading unit according to the parameters of residual contamination and losses of clean grain. It was found that the residual contamination decreases exponentially along the length of the doll cylinder. The loss of clean grain to waste grows linearly. It was found that the loss of pure grain to waste along the length of the oat cylinder decreases exponentially. A formula has been obtained to determine the optimal length of the indented cylinder, which depends on the degree of impurity release and the amount of pure grain loss for the doll cylinder. The criterion of optimal operation of the indenter block has been substantiated. The hypothesis about the same degree of impurity release along the entire length of the indented cylinder was confirmed. On the basis of the results obtained, recommendations are given for the developers of indented blocks.

DISINFECTION OF MARKETABLE EGGS BY PLASMA-CHEMICALLY ACTIVATED AQUEOUS SOLUTIONS

Microbiological purity of raw materials and finished products is one of the most important factors of food safety. The acceptable level of microbiological contamination is provided by a set of sanitary and hygienic techniques in the course of manufacturing, selling, and consuming food products. It has been suggested that eggs should be disinfected by treating them with plasma-chemically activated aqueous solutions in order to reduce microbial contamination of the egg surfaces and remove salmonella from them. The surface of eggs is disinfected with aqueous solutions activated by non-equilibrium contact plasma with the different time of activation of these solutions. Plasma-chemically activated aqueous solutions act as high-quality disinfectants. They contain an active substance (hydrogen peroxide) with the concentration of 100 to 700 mg/l, and have pronounced antiseptic properties. The studies have revealed that with the use of plasma-chemically activated aqueous solutions as a disinfectant, the number of bacteria and fungi on the eggshell is significantly reduced. For example, E. coli and S. Enteritidis were not found in samples at the peroxide concentration as high as 100 mg/l, while the total bacterial contamination and pathogenic microflora under study (E. сoli, Asp. fumigatus, S. Enteritidis) were absent at 300 mg/l concentration of peroxides. Besides, our research included bacteriological studies of marketable eggs in storage. Thus, plasma-chemically activated aqueous solutions with the peroxide concentration 300 mg/l, besides destroying the pathogenic microflora completely (as evidenced by the total absence of QMAFAnM, CFU/cm3, S. enteritidis, E. coli, Asp. fumigatus in the studied samples), had a long-term disinfection effect: no pathogenic microflora appeared on the surface of the eggs within a month. This will allow extending the shelf life of marketable eggs. The studies of microbiological parameters of the dirty eggshells treated with plasma-chemically activated aqueous solutions have shown that the 400 mg/l concentration of peroxides allows getting rid of coliform bacteria, staphylococci, salmonella, spore-forming microflora, which makes a product saleable. The outward appearance of raw materials improves as well, which indicates a wide range of applications of the proposed technology of egg surface disinfection.

Assessment of the Distribution of Heavy Metals in Soils of Severny Island (Novaya Zemlya)

Global warming occurs the fastest in polar latitudes, increasing their economic accessibility and, consequently, entailing risks of technogenic contamination. Heavy metals (HM) are among the most common technogenic pollutants that may negatively affect the functioning of the Arctic's soil-based terrestrial ecosystems. There is almost no research on the actual HM content in the soils of Novaya Zemlya (NZ), and the purpose of this work is to assess the HM content in the soils of Severny Island in the NZ archipelago. The study was performed at Russkaya Gavan, Ledyanaya Gavan, Blagopoluchiya Bay, and Cape Zhelaniya. The soil cover in the northern part of Severny Island has a mosaic structure. On Severny Island, Cryosols (Loamic) are the most common soils among the soils studied in this work. Soils of the study regions on Severny Island are mostly loamy and clayey. The proportion of physical clay increases down the profiles. All study soils of NZ are alkaline and highly alkaline. In general, study soils have an acceptable level of HM contamination. The weighted average HM gross content in them varies insignificantly; however, the following elements exceed their threshold concentrations: Fe (1.1 clarke) – Russkaya Gavan bay; Fe (1.2 clarke), Cr (1.1 clarke), V (1.1 maximum permissible concentration (MPC)), Ti (1.1 clarke) – Blagopoluchiya bay; Fe (1.3 clarke) – Ledyanaya Gavan bay. This, apparently, is caused by their high contents in the soil-forming rock. The results obtained confirm the necessity to monitor the study territories in order to be able to assess the degree of pollution and prevent the risk of an environmental disaster in the future

Aflatoxin Contamination and Rancidity in Locally Processed Commercial Fish Feeds and Ingredients along the Value Chain in Wakiso and Kampala Districts, Uganda

Aflatoxin contamination and rancidity in locally processed commercial fish feeds and ingredients along value chains is a Public and Animal health hazard. The study established the level of aflatoxin contamination, peroxide value (PV), Anisidine value (AnV), and their associated factors at storage areas among farmers, processors, traders, factories, and landing sites in the Wakiso and Kampala districts. The value chain actors were purposively selected in a cross-sectional study based on access to the feed store and the use of locally processed commercial fish feeds on farms. Data collected were statistically analyzed in SPSS version 20. All the samples (45) were positive for aflatoxin contamination and PV with 51% (23/45) of samples being contaminated with “above acceptable” aflatoxin levels and 66.6% (30/45) of samples with “above acceptable” PV. The overall percentage of “above acceptable” AnV was 11/29 (37.9%). Samples from factories were within acceptable contamination levels. Multivariate logistic regression analysis revealed no significant difference between aflatoxin contamination, peroxide, and Anisidine value with storage factors for locally processed commercial fish feeds and ingredients. The study recommended the purchase of fish feeds from factories and a larger study on storage factors responsible for aflatoxin contamination and rancidity in fish feeds in Uganda.

Surroundings: A History of Environments and Environmentalisms

Surroundings: A History of Environments and Environmentalisms

Monitoring of location and dispersion parameters of production processes using hybrid control charts

In practical terms, the measurement data from production processes are usually contaminated which may translate into failure to meet the assumed normality. In consequence, using classical Shewhart control charts to monitor the stability of production processes leads to the occurrence of numerous false signals. The purpose of this article is to propose hybrid control charts and to investigate their performance in monitoring the parameters of location and variability of production processes for which there occurs contamination of measurement data appearing at the stage of monitoring production cycles. To construct the control charts proposed by the authors, we should use extended control limits of classical Shewhart charts for means and ranges (Phase I) and robust estimators as test statistics to control the production cycle (Phase II). The article demonstrates the conducted simulation testing of classical and robust estimators for location and dispersion in terms of their effectiveness, as well as determining the relationship between them. These analyses have contributed to the design of hybrid control charts. Comparative simulation tests of classic and hybrid control charts performance have confirmed the effectiveness of the suggested measures. It follows that the proposed control charts can replace the classic counterparts, because they do not respond to an acceptable level of measurement data contamination, thanks to which it is possible to avoid taking unnecessary corrective actions in the production process. The theoretical portion is closed by a case study based on actual data which aims to illustrate the proposed approach.

Removal of Arsenic Oxyanions from Water by Ferric Chloride-Optimization of Process Conditions and Implications for Improving Coagulation Performance.

The chronic ingestion of arsenic (As) contaminated water has raised significant health concerns worldwide. Iron-based coagulants have been widely used to remove As oxyanions from drinking water sources. In addition, the system’s ability to lower As within the maximum acceptable contamination level (MCL) is critical for protecting human health from its detrimental effects. Accordingly, the current study comprehensively investigates the performance of As removal under various influencing factors including pH, contact time, temperature, As (III, V) concentration, ferric chloride (FC) dose, and interfering ions. The optimum pH for As (V) removal with FC was found to be pH 6–7, and it gradually decreased as the pH increased. In contrast, As (III) removal increased with an increase in pH with an optimum pH range of 7–10. The adsorption of As on precipitated iron hydroxide (FHO) was better fitted with pseudo-second order and modified Langmuir–Freundlich models. The antagonistic effect of temperature on As removal with FC was observed, with optimum temperature of 15–25 °C. After critically evaluating the optimum operating conditions, the uptake indices of both As species were developed to select appropriate an FC dose for achieving the MCL level. The results show that the relationship between residual concentration, FC dose, and adsorption affinity of the system was well represented by uptake indices. The higher FC dose was required for suspensions containing greater concentration of As species to achieve MCL level. The As (V) species with a greater adsorption affinity towards FHO require a relatively smaller FC dose than As (III) ions. Moreover, the significant influence of interfering species on As removal was observed in simulated natural water. The author hopes that this study may help researchers and the drinking water industry to develop uptake indices of other targeted pollutants in achieving MCL level during water treatment operations in order to ensure public health safety.

Metal concentrations in marine sediments of the Rio de Janeiro Coast (Brazil): A proposal to establish new acceptable levels of contamination

This work aims to propose new standards to assess the degree of sediment contamination in saline and brackish environments, since the legislation currently used in Brazil is based on Canadian/American regulations, which do not comply with the conditions in Brazil. This study is based on geochemical analyses of 340 surface sediment samples collected in the Green Coast region (Rio de Janeiro, Brazil), including Mangaratiba, Angra dos Reis and Ribeira coves and Ilha Grande and Sepetiba bays. This region is influenced by industrial, harbor, urban and tourist activities and was affected by a dam rupture episode that released contaminated material. The results show heterogeneity in the distribution and range of metal concentrations in the study area depending on the supply of metals from natural and anthropogenic sources. Environmental characteristics such as coastal and tidal currents, water temperature and salinity, local depth, sediment grain size, sedimentary dynamics and biogeochemical processes influence the dispersion or retention of metals. The pollution load index (PLI) suggests that Sepetiba Bay is the region with the most environmental degradation due to anthropogenic contamination. In this context, we propose the establishment of new levels of contamination according to the Cd, Cr, Cu, Mn, Ni, Pb, V and Zn concentrations in sediments of salt and brackish waters, considering I) background level; II) level 1 - with anthropogenic influence; and III) level 2 - contaminated. The results of this work also suggest that, except for zinc, the range of metal concentrations admitted by Brazilian legislation are quite permissive and not adequate for Brazilian coastal environments.

Some aspects of obtaining the radiologically safe vegetable products in the conditions of Ukrainian Polissia

Considering the urgent need for rehabilitation ofthe Chоrnobyl-affected agricultural lands of Ukrainian Polissia and maximization of the restoration of agricultural production in this area, the issue of reorganization of vegetable growing as one of the most radioecologically problematic in the region deserves to be specially highlighted. The study aimed to determine the influence of species and varietal characteristics, as well as soil, fertilizers, and irrigation on the accumulation of 137Cs by vegetable crops in the remote period after the Chornobyl accident. The research was conducted during 2008–2012 in the II, III, and former IV radioactive contamination zones on the territory of Chernihiv, Kyiv, and Zhytomyr regions. The soil cover of the studied area is represented by sod-podzolic sandy and peat-swamp soils. The most common for the region and recognized species and varieties of vegetables were studied, the list of which was determined by a questionnaire: cucumber; zucchini; pumpkin; scallop; red beet; garden carrot; red cabbage; Savoy cabbage; white cabbage, potatoes of different maturity groups, parsley. Soil and plant samples were taken during the industrial ripeness and the flowering (for potatoes) phases of vegetables. To study the effect of elevated doses ofmineral fertilizers and moldon the value of the 137Cstransfer factor from soil to potato tubers, a complex of mineral fertilizers was used: ammonium nitrate (34% N), tagged superphosphate (19% P2O5), potassium sulfate (50% K2SO4) and hummus made from hog manure. Acceptable levels of soil contamination with 137Cs were calculated by the formula based on the transfer factors and the effectiveness of agricultural measures conducted. The peculiarities of 137Cs accumulation in vegetable products depending on the species, variety, soil, fertilizer, and irrigation have been analyzed and the corresponding acceptable levels of soil radioactive contamination have been determined. The most severe restrictions to vegetable production in radioactively contaminated areas have been set forleaf vegetables, as well as for growing on peat-swamp soils. It has been confirmed that the greatest reduction in the 137Cs intake by vegetables is achieved by irrigation with fossil groundwater. The research findings make it possible to calculate the maximum acceptable levels of 137Cs soil contamination for growing different recognized varieties of vegetables under different fertilizer combinations and irrigation for a certain soil type. Guidelines for vegetable production on radioactively contaminated soils have been proposed, taking into account the varietal characteristics of the crop, fertilizer, and irrigation.

Study of the dependence of the formation of welding aerosol in electric arc welding using electrodes with basic, ruthyl and ruthyl-cellulose coating

Problem statement. Electric arc welding is characterized by a significant number of harmful and hazardous production factors that lead to the development of occupational diseases of the welder, therefore the most important task of any production is the creation of safe working conditions. The safety of welding works entirely depends on the level of professional skill, knowledge and skills of their performance by the welder. The purposeof the article is to study the operating modes of an electric welding machine and determine the least dangerous of them from the point of view of the emission of welding aerosol, depending on the current and time of the welding process for three main groups of electrodes used in welding technologies. Conclusions. The analysis of the research results at the welding site when using electrodes with various types of coating provides in article. The harmful factors arising from the use of various types of welding technologies are analyzed. Changes in the concentration of welding aerosol, which are formed during manual electric arc welding and the use of electrodes with the main type of coating, rutile and rutile-cellulose, have been investigated. The mathematical dependences of the processes of formation of welding aerosol (SA) were determined using a full factorial experiment of the FFE-22 type. The studies were carried out in the welding laboratory of the National Technical University "Kharkiv Polytechnic Institute" at the welder's workplace where ventilation is installed in the form of an umbrella in which there are 8 holes in the form of an equilateral triangle, with a side size of 5 × 20 × 20. The nature of the propagation of welding aerosol, which can cause diseases of welders, has been established. The modes of operation of the electric welding machine are analyzed and the least dangerous of them are determined depending on the current and time of the welding process for three main groups of electrodes that used in welding technologies. The dependence of the concentration of the welding aerosol on time was studied when using electrodes with the main type of coating when using ventilation, without ventilation and simultaneously with ventilation and the vacuum cleaner. The necessity of choosing electrodes with a smaller amount of welding aerosol emissions into the air of the working area is considered. Evaluation of the efficiency of exhaust ventilation at the welding site and at the same time the use of exhaust ventilation with a dust collector was carried out, and it was concluded that the use of only exhaust ventilation cannot provide an acceptable level of contamination in the air of workplaces and indoors.

Assessing site signal preservation in reference chronologies for dendro-provenancing.

Regional differences in tree growth can be used to approximate the geographical provenance of ring-width series (‘dendro-provenancing’). This method relies on cross-dated ring-width series (reference chronologies) that are thought to represent the radial growth signal of trees in a given region. Reference chronologies are often established from ring-width series of living tree populations. Frequently, they are too short to allow for investigating the provenance of historical wood. Thus, references are extended by ring-width series from buildings and art-historical objects that exhibit best matching growth patterns with the living tree references. Yet, series from other provenances may erroneously be included. Thereby the local or regional growth signal of the references is progressively contaminated, but this has received little attention to date. I investigate this contamination risk using a simulation approach that allows for generating pseudo site chronologies that preserve the relevant statistical properties of the real site chronologies. While the exact provenance of historical wood is unknown, for simulated ring-width series the provenance is unambiguous. Hence, pseudo reference chronologies may be established while monitoring the signal mixture. Specifically, 15 site chronologies of Norway spruce (Picea abies (L.) H. Karst.) from northeastern Switzerland were used to generate 15 pseudo site growth signals that span 1000 years. The simulation demonstrates that quasi uncontaminated references can be established in ideal circumstances for the study area. However, the thresholds for the similarity in between-series correlation must be very high. Even then, contaminated pseudo references occurred in rare cases during the simulation. Yet, elevation-specific pseudo references were established with lower thresholds. Simulation currently offers the only approach for assessing the contamination risk of reference chronologies, and it allows for elucidating the conditions under which acceptable levels of contamination can be guaranteed. Therefore, the present approach paves the way towards a practical simulation tool for dendro-provenancing.