The effect of the change in current on the size of powder particles during their transfer through the high-temperature stream and the degree of particle deformation upon impact with the substrate was determined. It was found that during transfer through the plasma jet, there was an increase in the average size of sputtering products by two–three times compared to the initial effects of mechanochemical synthesis due to the coagulation of some particles. In this case, an increase in current from 400 to 500 A led to a growth in average particle size by 14–47% due to the partial evaporation of fine particles with an increase in their heating degree. An increase in current also led to a 5–10% growth in particle deformation degree upon impact on the substrate due to the rising temperature and velocity of the plasma jet. Based on the research, the parameters of plasma spraying of mechanically synthesized Fe3Al intermetallic-based powders were determined, at which dense coatings with a thin-lamellar structure were formed.The present paper presents a study of the behaviour of Fe Iron aluminide-based intermetallic alloys, due to their physicochemical and mechanical properties, as well as their stable structure and resistance to high-temperature corrosion, are promising materials for heat exchangers, nuclear reactor components, automotive exhaust systems, etc. ,2,3,4,5.Iron aluminides have found a wide practical application as protective coatings obtained by thermal spraying, especially HVOF, plasma (PS), and Arc and D-gun spraying ,9,10,11.At present, one of the ways to obtain composite intermetallic powders of the Fe-Al system for thermal spraying is the mechanochemical synthesis method (MCS) ,16,17.3Al-based intermetallic coatings by plasma spraying.It should be noted, however, that unlike the D-gun process ,10, the 3Al structure stabilising around the FeAl structure at high temperatures. Strengthening with dispersed precipitations of hexagonal Laves phase 2Ti can take place in addition to strengthening due to structure ordering in the Fe–Al–Ti system. Furthermore, there is a specific range of composition in the Fe–Al–Ti system, where coherent structures [3Al intermetallic compound, it is possible to expect strengthening by incoherent compounds. Commercially available powders of the alloys Al5Mg and Ti37.5Al were used instead of the pure elements of aluminium, magnesium, and titanium to reduce the degree of oxidation of the MCS products.Iron aluminide powders obtained by mechanochemical synthesis were used as research material, while iron, aluminium, aluminium alloy (Al5Mg), and Ti37.5Al intermetallic powders were applied as starting materials. Using Ti as an alloying element allows for realising several mechanisms of iron intermetallic strengthening, namely structure ordering, strengthening with dispersed inclusions, and the formation of coherent microstructures. Titanium differs by significant solubility in a solid state in Fe–Al phases that result in Feructures  are formThe MCS process was performed in a planetary-type mill «Aktivator 2SL» for 5 h. The relation of the mass of balls to the mass of powder was 10:1. The central axis of the mill triboreactor was rotated at a 100 rpm rate; drums rotated around their axis at a 1500 rpm rate. Parts of the jar and milling agents were manufactured of 100Cr6 steel. The MCS process was performed in the air. Surface-active substances (SAS), namely oleic acid, were added to the mixture to prevent pickup of processed charge on the milling agents and jar wall, and to intensify the process of new synthesis phases.3 intermetallics in the case of AlMg that corresponded to 14 wt.% of Al-alloy and 3Al in the case of TiAl intermetallics. In the latter, the variant amount of introduced TiAl was 39.2 wt.%.The amount of aluminium alloy powder introduced in the mixture with iron powder was selected for formation in MCS of Fe3Al iron aluminide) were confirmed, respectively, by SEM/EDS and XRD analysis using a JEOL 5310 microscope (Japan) operating at 20 kV, and a XRD Simens D-500 diffractometer (Germany) with CoKα radiation (λ= 0.178897 nm). An angular step size of 0.02°/min and a step time of 5 s per point were used, respectively.The microstructure, chemical, and phase composition of the MCS powder products  Ar+N2 flow rate of 25 SLPM  flow rate, and powder feed rate were constant in all experiments. The Ar/N2 ratio (7.3/1) and the flow rate of the plasma gas mixture (25 SLPM) made it possible to ensure the stable operation of the plasmatron at a voltage of 40 V. The modes of PS operation are presented in Powder spraying was carried out using the UPU–8M atmospheric plasma spraying device at different arc current (I) parameters. Changing the current significantly affects the temperature and velocity of PJ, which determines the heating and velocity of the particles during transport in the stream . The volStudies of the PS processes occurring in the powder during spraying were carried out by collecting particles transferred through the plasma jet into the water at a distance of 120 mm from the end of the plasma torch to the water’s surface. The analysis of the size and microstructure of the particles of sprayed powders collected in the water bath will determine the processes taking place with the powder particles in a plasma jet, on which the further formation of the coating structure depends.The state of the sprayed particle material after impact on the substrate was studied using the splat test. Spraying was carried out by moving polished stainless steel plates of 50 × 30 × 0.5 mm in a plane perpendicular to the jet axis . As a re–4 Pa), with an accelerating voltage of 20 kV.To investigate powders sprayed into the water and evaluate the degree of deformation of particles after their impact on the substrate, a complex technique was used, including the analysis of particle size distribution–ASOD-300 laser analyser ; metallographic examinations–optical microscope “Neofot-32” with an attachment for digital photography; measurement of splats diameters (D) and classification of splats by appearance–optical microscope Jenavert; scanning electron microscopy (SEM)–scanning electron microscope JSM-6390LV  with an attachment for energy dispersive analysis INCA in the secondary electron mode, in low vacuum  was used, which consists of determining the area per detected pores relative to the entire area of the coating cross-section (ASTM E2109-01). Image-Pro Plus 7 software processed the digital image of the microstructure of the coatings.3Al, Fe-AlMg, and Fe-TiAl systems sprayed into the water at different currents is shown in The appearance of powders of FeIt is known  that whe3Al and Fe-AlMg powders. This is explained by the tendency of Ti and Al powder components to oxidize and their higher content in the initial powder mixtures. The reduced iron content in powders of the Fe-TiAl system also indicates the formation of an oxide film on the particle surface.The oxygen content in powders of the Fe-TiAl system is, on average, two times higher than the oxygen content in FeThe microstructure of powders  shows th3Al, Fe-AlMg, and Fe-TiAl powders after the conglomerates transferred through the plasma stream at different currents are shown in Histograms of the particle size distribution of FeMCS products also simultaneously fuse with the destruction of conglomerates in the plasma stream. As a result, the average particle size increases 2–3 times relative to the initial MCS products .The increase in current leads to a 38–57% decrease in the number of particles within the size range of 10...20 μm and a 14–47% increase in the average particle size . This maAnalysis of the shape of individual splats on substrates is one of the factors in optimizing plasma spraying methods. The degree of particle deformation D/d on impact with the sprayed surface determines the particle’s surface contact area. The larger deformed particle size D compared to the initial particle size d in the gas stream in front of the sprayed surface, the greater probability of strong adhesion of the contacting materials, with all other conditions being equal.3Al, Fe-AlMg, and Fe-TiAl powders as a function of current intensity is shown in The appearance of splashes obtained by spraying FeFrom the splats obtained during the interaction of powder particles with the substrate in all three modes, it can be concluded that the particles are in a fully molten state at the moment of impact with the substrate and have a disk shape. After the impact of the particles on the substrate and spread across the surface, the central part of the splats turns out to be unfilled by the material. This is explained by the fact that, inside the droplet, cavitation processes occur when it hits the surface of a solid; i.e., bubbles form and grow as the pressure drops to the saturation vapour pressure. The bubbles break through the liquid coating of the droplet and form crater-like holes in the deformed powder particle .The results of estimating the degree of deformation of D/d particles after impact on the ground are shown in The dependence of the average splat diameter and the degree of particle deformation on the current is shown in As a result of the plasma spraying of these powders, the coating layers are formed from completely melted and deformed particles, so the coatings have a dense thin-lamellar structure with a small number of oxide films at the lamella boundaries . The coa3Al coating, Al2O3 aluminium oxide is present; in the Fe-AlMg coating, complex oxide MgAl2O4 and in the Fe-TiAl coating, titanium oxide TiO are present  was transformed into the intermetallic phase 3Al.During the spraying of coatings of intermetallic powders, their phase composition does not completely coincide with the composition of the initial powders, which is associated with the active development of the process of particle oxidation during their flight. Oxides are present in all coatings. In the Fe present . In the Changes in the phase composition of the coatings do not occur when the spraying mode changes.The characteristics of coatings obtained under different modes of plasma spraying are given in As expected, the porosity of the coatings decreases (on average by 2%) with an increase in current from 400 to 500 A a, which 3Al and Fe-AlMg coatings show a slight increase in microhardness relative to the initial MCS powders. This is most likely due to the formation of oxides in the coatings during spraying. In the case of sputtering of the Fe-TiAl powder, an increase in the microhardness of the coating relative to the microhardness of the initial MCS powder by ~2.3 times is noted. This is due to the formation of an intermetallic phase 3Al in the coating with additional hardening of the coating by the TiO oxide phase.The results of measuring the microhardness of FeFrom 3Al-based iron aluminide powders obtained by the MCS method, it is advisable to carry out the spraying process at the following spraying parameters: voltage of 40 V, current of 500 A, plasma–Ar/N2 gas mixture in the ratio of 7.3:1.Thus, to obtain plasma coatings with a dense lamellar structure and high adhesion and cohesion strength from Fe3Al, Fe-AlMg, and Fe-TiAl) obtained by mechanochemical synthesis was analysed at the stage of their transfer through the volume of the high-temperature plasma jet and after impact on the sprayed surface, depending on the intensity of the arc current in the plasma spraying process;The behaviour of particles of iron aluminides powders (FeIt was established that, as a result of the contact of molten particles with oxygen-containing zones of the plasma jet, aluminium oxide films are formed on the surface of the particles, which acquire a dome shape when the particles are carried by the turbulent plasma jet;It was noted that, during the transfer of particles through the plasma jet, the initial particles are coagulated, resulting in their average size increasing from 9–15 µm to 19–31 µm;An increase in current leads to a 5–10% increase in the degree of particle deformation upon collision with the substrate as a result of the increase in temperature and plasma jet velocity;3Al intermetallic compound leads to the formation of coatings with a denser structure due to an increase in the degree of particle deformation during the formation of the coating layer;It has been found that an increase in current from 400 to 500 A during the plasma spraying of powders based on the Fe3Al-based powders, it is advisable to use the following plasma spraying parameters: voltage 40 V, current 500 A, plasma-forming gas–Ar/N2 mixture at a ratio of 7.3:1.As a result of the research carried out, it was determined that, for the formation of coatings with a thin-lamellar dense structure and a dense boundary with a steel substrate from MCS intermetallic Fe


In the original publication, there were publisher errors in the names of authors Zhen-xin Wang, Xi-long Feng and Jin-ming Gao and affiliation (1) of the first, second, fourth and fifth authors (name of the Key Laboratory and city). This correction was approved by the Academic Editor. The original publication has also been updated.Figure 2 as published. The correct structure of compound 2 was not listed, and structures 2–24 did not match the corresponding descriptions in the article. The corrected Figure 2 appears below.In the original publication , there wFigure 8 as published. The text notes in the lower right corner of this figure should cite references 48 and 49, not 47 and 48, respectively. The corrected Figure 8 appears below. In the original publication, there was a mistake in The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated.


Cypridopsis vidua and Heterocypris sp.), Vibrio fischeri and Vicia faba L. Higher concentrations of heavy metals at individual sites  resulted in higher mortality of ostracods, higher inhibition of Vibrio fischeri luminescence and a significant reduction in germination and pigmentation of broad beans. The results of the biotoxicity evaluation were consistent with the results of the physicochemical evaluation, allowing for a more direct and comprehensive evaluation of the ecotoxic effects of uranium and heavy metals in the mine soils.To investigate the heavy metal contamination of soil in a uranium mining area in northern Guangdong, a physicochemical evaluation method was used to evaluate the contaminated soil near the pit and tailings pond of the uranium mining area, determine its heavy metal content and evaluate its ecological risk using the Nemerow integrated contamination index, ground accumulation index and potential ecological risk index. The results show that the average content of nine heavy metal elements in the soil of the uranium mining area exceeds the background value of red soil in Guangdong Province. Three pollution evaluation indices all indicate that Cd, As and U have serious pollution and high ecological risk, while the remaining elements are weakly polluted and the potential ecological risk of the six sampling sites all show very strong risk. On this basis, soil ecotoxicity was evaluated using ostracods ( After more than 30 years of development of nuclear power, China has made remarkable achievements ,2. UraniBiological monitoring is commonly used to evaluate the genotoxicity and mutagenicity of contaminants in organisms. Vibrio fischeri luminescence is the basis of several biologic methods of toxicity detection systems, including monitoring chemical toxicity in sewage and soil ,22,23. HCypridopsis vidua and Heterocypris sp.), Vibrio fischeri and Vicia faba L. Organisms were evaluated for soil ecotoxicity, and the results of the biological evaluation were compared with physicochemical data to scientifically evaluate the ecotoxic effects of soil uranium and heavy metal elements in this uranium mining area.A uranium mine in northern Guangdong is a vital uranium resource production base in China, with more than 50 years of mining history, and its surrounding ecological environment has inevitably suffered some degree of damage. At present, ecological monitoring and evaluation of this uranium mining area are still infrequent, and biological evaluation has not been reported. Therefore, in this study, we collected surface soil samples near a uranium mining area in northern Guangdong, determined their uranium and heavy metal element contents and evaluated them on the basis of physicochemical analysis by using three different trophic levels of ostracods  of the dried soil sample in a polytetrafluoroethylene crucible, wetting it with a small drop of distilled water and then adding HCl, HNO3 in steps of 0, 0.02, 0.04, 0.036, 0.08 and 0.1 mg·mL−1 for standard curve making.This study selected Mn, Ni, Cu, Cd, Pb, Zn, Cr, As and U, nine elements for testing, inductively coupled plasma mass spectrometer ICP-MS (X-Series11) for testing and analysis, completed in the National Defense Key Discipline Laboratory of Uranium Mining and Metallurgy Biotechnology, University of South China. The national standard soil GSS-25 was measured before determination of the samples to ensure the accuracy and reliability of the results. Each sample was tested three times, and Ge, In and Bi were selected as the standard internal elements to ensure the stability of the instrument and to obtain RSD < 5% for each element. The multielement standard solution was diluted with 5% HNOiP is the pollution index of heavy metal element i, iC is the measured concentration value of heavy metal element i, iS is the evaluation criterion of the heavy metal element, NP is the Nemerow pollution composite index, imaxP is the maximum value of iP and iaveP is the average value of each pollution element index. In this study, the background value of heavy metal elements in the zonal soil of Guangdong Province was chosen as the evaluation standard. The pollution level was divided into 5 levels according to the Nemerow integrated pollution index method, as shown in The Nemerow composite index method is one of the most commonly used evaluation methods by domestic and foreign scholars; it was proposed by the American scholar Nemerow in 1977 and is widely used for soil pollution evaluation ,36,37,38tot), which is defined as the sum of all heavy metal ground accumulation indices (geoI) within an area. The geoaccumulation index was calculated as follows:geoI is the geoaccumulation index, iC is the measured content of heavy metal element i, iB is the geochemical background value of heavy metal element i and K is generally 1.5. The classification of the ground accumulation index evaluation results is shown in The geoaccumulation index method is an evaluation method proposed by the German scientist Müller in 1969, which considers not only the influence of anthropogenic pollution factors and environmental geochemistry on the background values but also the possible changes in background values due to natural diagenesis ,41. MeanfiC is the pollution index of element i, where riC is the measured content of element i and niC is the background value of element i; riE is the potential ecological risk of element i at the same point, where riT is the toxicity response coefficient of element i and RI is the combined potential ecological risk of multiple elements at a sample point. The specific risk evaluation levels of the method are shown in The potential ecological risk index method is a heavy metal pollution evaluation method proposed by the Swedish scientist Hakanson based on the nature and environmental behavior characteristics of heavy metals . The metCypridopsis vidua and Heterocypris sp., both of which were cultured for a long time in the laboratory , precultured for one week before the experiment and fed 24 h before the start of the formal experiment using the 4-day direct exposure acute toxicity test method. The test was performed on adult individuals of similar size and vigor and the solution temperature, pH, conductivity and dissolved oxygen content were measured before and after the experiment. There were 3 parallel groups for each sample, and a blank control group was set up. Ten worms in each treatment group were placed in beakers with 40 mL of sample extract , and the number of dead worms in each treatment group was observed and recorded at 24, 48, 72 and 96 h. A time-point mortality curve was obtained. A total of 190 worms in 19 treatment groups were used for this experiment, and death was defined as the absence of life activity within 15 s of shaking the beaker.The experimental organisms were Vibrio fischeri lyophilized powder: Vibrio fischeri lyophilized powder was purchased from Zhejiang Tocos Biotechnology Co. Vibrio fischeri lyophilized powder was prepared according to the ISO–11348 standard [Preparation of standard . AccordiRecovery of strain and preparation of bacterial solution: One part of Vibrio fischeri lyophilized powder and one part of recovery solution were combined and equilibrated at room temperature for 15 min. Two milliliters of recovery solution was injected into the lyophilized powder reagent bottle and left for 10 min. After the recovery was completed, Vibrio fischeri was diluted with 2% sodium chloride solution at a ratio of 1:4 to obtain bacterial dilution solution.Soil sample detection: The bacterial dilution was mixed with the sample to be tested at a ratio of 1:90, and a blank group was set up with a reaction time of 15 min. The luminescence intensity was measured with a bioluminescence detector (Glomax 20/20 bioluminescence detector), and the relative luminescence intensity (relative luminescence intensity = sample luminescence intensity/blank luminescence intensity) was calculated. The luminescence inhibition rate = 1−relative luminescence intensity. The luminescence inhibition rate =1−relative luminescence intensity.Seedling growth assay: Whole, uniform broad bean seeds were sterilized with 0.5% NaClO solution for 20 min, rinsed and soaked in distilled water for 1 day. Place them in a Petri dish lined with double–layer filter paper, add 10 mL of each treatment solution (distilled water was used as the control), add 8 broad bean seeds per treatment group, set up three parallel samples for each concentration treatment and incubate them at 25 °C for 7 days under no light conditions. After 3 days of germination, the number of seeds germinating was observed and recorded on a daily basis , germination rate = the number of seeds germinating at 7 days/number of seeds tested × 100%.The chlorophyll content was determined by the colorimetric method. On the 7th day of incubation, 0.1 g of leaves were taken from each of the three parallel samples of each concentration in the same position, placed in a centrifuge tube, 10 mL of 80% acetone was added and the absorbance values were measured at 663 mm, 646 mm and 470 mm in the dark for 40 h (after the leaves had whitened), with 80% acetone as the control.The calculation formula is:The soil pH varied from 7.25 to 7.40, with a mean value of 7.32, which was weakly alkaline. The total amount of heavy metals in the soil samples was positively correlated with the conductivity; that is, the conductivity of the sample points with low heavy metal contents also decreased. The heavy metal content in this study was significantly controlled by the source of pollution, i.e., the closer to the source, the higher the heavy metal content of the samples in general, and the distance increased, the heavy metal content decreased, and the relationship with organic matter content was not significant.The heavy metal content of the soil in the study area is shown in NP ranged from 102.97 to 213.66, with an average of 171.80. The lowest and highest values were found at the P1 point and the highest at the T1 point. The order of the Nemerow comprehensive pollution index from large to small was T1 > T2 > P2 > P0 > P3 > P1. Overall, the six samples in the study area were all severely polluted, and the main contributing factor was Cd. The average value of the single pollution index was 239.56.The Nemerow Integrated Pollution Index method evaluates both the average and maximum values of individual pollution indices, highlighting the impact and effect of the more polluting pollutants on the environment and is able to comprehensively reflect the overall quality of the soil environment; the evaluation results are shown in geoI) evaluation show that Cd and As are severely polluted, Co and U are moderately polluted, Zn is moderately polluted, and Mn, Pb, Ni and Cu are lightly polluted. The results of the Integrated Geoaccumulation Index (Itot)  b indicatIgeo) evaluation show that Cd and As are severely polluted, Co and U are moderately polluted, Zn is moderately polluted and Mn, Pb, Ni and Cu are lightly polluted. The results of the Integrated Geoaccumulation Index (Itot)  b indicatriT. Hakanson has set toxicity factors based on the toxicity of different elements. The toxicity factors for the heavy metals involved in this paper are 1 , 5 , 10 (As) and 30 (Cd) and the toxicity factor for radionuclide U is currently missing, but there is no doubt about the severity of its impact on the environment, which is both chemically and radiologically toxic. Therefore, this paper set the toxicity coefficient of U by referring to Cd element 30, which has the highest toxicity coefficient among the studied heavy metals. As and U showed high risk, and Co showed low risk. The evaluation results for the elements Mn, Ni, Cu, Zn and Pb showed no risk, with a small fluctuation range at each sampling point. The potential ecological risk index for heavy metal elements in the uranium mining area is Cd > As > U > Co > Pb > Ni > Cu > Zn > Mn in descending order. Each of the sampling sites had the highest combined potential risk index rating, showing a very high risk.The evaluation of the potential ecological risk index of soil in a uranium mining area in northern Guangdong showed  that theIn comparison with the above two types of physical and chemical evaluation results, it was found that the results of the Nemerow integrated pollution index method, the evaluation of the geoaccumulation index and the potential ecological risk index method all indicated that Cd, As, Co and U were the main polluting elements in the study area and that their contributions to heavy metal pollution in the mine area were greater. The corresponding evaluation results often differ for each method due to their different evaluation perspectives, with the remaining five elements being minor pollutants in their respective evaluation systems.Qin et al.  evaluateC. vidua, the highest mortality rate of 23.3% was recorded at sample site T2, followed by sample sites T1 and P2 with a mortality rate of 20%, and the lowest mortality rate of 6.7% was recorded at sample site P1 at the pit entrance for a 96 h termination time exposure. For H. sp., the 96 h termination time exposure had the highest mortality rate of 43.3% at the pit P2 sample site, followed by the T1 sample site with 40% and the lowest mortality rate of 3.3% at pit P3. The mortality rates of P2, T1 and T2 at the termination time of the two biological experiments were higher than those of other samples, and the potential ecological risk index of these samples was higher The study area as a whole is at a high-risk level, with higher levels of contamination in tailings ponds than in pits. Cd, As and U are the main polluting elements in the study area. The degree of elemental contamination in the tailings ponds was negatively correlated with the distance from the tailings ponds.(2)A combination of physical and chemical evaluation and biological evaluation is used to more directly and comprehensively reflect the characteristics of uranium and heavy metal contamination in mine soils.The main insights gained in this paper are as follows:


The study group consisted of 4296 patients with lung adenocarcinoma and the level of selected pollutants. To analyse the data, a standard statistics for cohort data, that is a risk ratio (RR), was used. The dependencies occurring in the distribution of pollutants and cancer incidence were examined using Moran’s I correlation coefficient. The current study suggests that PM10, NO2 and SO2 exposure as an air pollutant may increase female lung adenocarcinoma incidence. In men, the increased risk of adenocarcinoma lung cancer is affected by SO2 and PM10. A high morbidity rate in urban areas and suburbs may be connected with commuting from moderately polluted living areas to highly polluted working areas.The aim of this study was to assess the association of long-term exposure to particulate matter with aerodynamic diameter, PM2.5, PM10, NO Cigarette smoking is an important risk factor in the aetiology of lung cancer. It has been well established throughout numerous epidemiological studies ,2,3 and 2) ,10,11 or2) [2) ,12. Exog2) [2) ,14, whic2) [2) ,15. Due The most common types of lung cancer include squamous cell carcinoma (SCC), adenocarcinoma and small cell carcinoma (SCLC). Until the nineties of the twentieth century, SCC was the most common histologic subtype, particularly among men. Over the years, the situation has changed, causing an increase in the number of ADs and a simultaneous decrease in the number of cases of SCC. This trend has been observed in countries in North America, Europe and Asia ,17. HoweScientists from different parts of the world have conducted observations on the possible impact of long-term exposure to selected particles and gases of air pollutants on lung cancer and its variants ,23,24,25Most of the 50 most polluted cities in the European Union are located in Poland such as Cracow, Wroclaw or Warsaw . Therefo2, and SO2 as well as CO at the place of residence on the morbidity of lung adenocarcinoma in south-east Poland.The purpose of this project was to evaluate the effects of long-term exposure to outdoor air pollution PM2.5, PM10, NO(1)What is the incidence of adenocarcinoma of the lung in relation to gender?(2)Is there a relationship between the incidence of adenocarcinoma of the lung and the individual components of air pollution in the analysed area?(3)Is there a trend in the morbidity of adenocarcinoma cancer in a ten-year follow-up?Based on the aim of this work, the research questions were posed:2, NO2, PM10, PM2.5 and CO pollution was hourly data from pollution measuring stations located in the Podkarpackie Voivodship in 2005–2014 from the Voivodship Inspectorate for Environmental Protection. The lack of source data in small areas was supplemented based on the average annual values determined from the OS-1 report for a given area. An autoregressive model with an exogenous variable [To examine the relationship between long-term exposure to selected concentrations of air pollution at the place of residence and the incidence of lung adenocarcinoma, original pollution maps were created with the places of residence marked. The source of data on incidence was the report of morbidity of lung cancer from Clinical Voivodship Hospital number 1 in Rzeszów from 2004 to 2014. The number of all lung cancer cases registered in the indicated period was 10,993. Research group included 4296 patients with AD. The subjects were divided by gender, as in recent years there was a tendency to a higher incidence of AD in women ,28,29,30The dependencies occurring in the distribution of pollutants and cancer incidence were examined using Moran’s I correlation coefficient . This coIf Moran’s I is close to one, then units tend to form spatial clusters. Opposite value can be interpreted as high local variability of variable of interest. No spatial pattern is indicated by Moran’s I close to zero.Spatial analysis was carried out under assumption of Queen contiguity  , which is the ratio of the incidence rate in the exposed group and the incidence rate in the control group . The expt from 1 .The region has many urbanised areas in the central and western part. The southern part is low urbanised due to mountains. The eastern part is dominated by woods and is located close to the state border. The next choropleth confirms the general expectation that cancer incidences are correlated with the pollutant level. Nevertheless, there are areas where there are cancer incidences but quite low levels of pollutants and vice versa. Therefore we applied several tools to quantify this phenomenon. 2  as well as by gender. The division into such age groups resulted from the median age of the people in the cancer incidence database. 2, NO2 and PM10. In contrast to women, no exposure to NO2 was observed in men (In the group of patients under 75 years of age, the impact of air pollution on the incidence of AD of the lung was observed to a greater extent in women, especially in relation to SOd in men . The analysis showed that the older group is exposed to the carcinogenic effects of all the analysed air pollutants, regardless of gender .In 2013 the International Agency for Research on Cancer classified outdoor air pollution as carcinogenic to humans . WorldwiThe subject of research all over the world is the analysis and attempt to determine the impact of long-term exposure to particulate matter in the air on the incidence of lung cancer ,23,24,252. Several patterns of spatial distribution of pollutants were discovered with the use of the pollution model, standard and spatial correlation coefficient, and density estimation. There are large areas with a stable low level of all pollutants, mostly rural areas. Cancer incidences seem to not be connected with pollutants. Next there are urban areas with very unstable and high levels of pollutants, which quite quickly decreases the levels of pollutants in the suburbs. The third type are industrial areas with industries that spread pollution over a large neighbourhood. The impact of these pollutant sources on cancer incidences is visible in neighbouring rural areas. New industrial zones are being created in the study area. These observations and further research may influence the creation of a certain border zone separating rural areas adjacent to industrial areas, creating a potential protective zone, not inhabited by society. An analysis of pollutants was carried out in two ways: comparing within a grid cell and comparing with neighbouring grid cells with an accuracy of 1 kmAD is the most common histological type of lung cancer in the population , with hiIn the European Study of Cohorts for Air Pollution Effects, data were used from 17 cohort studies based in nine European countries, and the meta-analyses showed a statistically significant association between higher hazards of risk for lung cancer with higher exposures to PM2.5 and PM10. Higher results of PM2.5 and PM10 were stronger associated specifically with AD . These sSlightly different results were shown in the seven cohorts from Europe. The analysis showed that long-term exposure to PM2.5 in the place of residence can affect the growth of lung cancer morbidity . These a2, PM2.5 and benzene. The NO2 level is often used as a marker for traffic-based air pollution [2 and the occurrence of lung cancer was not confirmed [2 and lung cancer. In Europe, there was a relative risk between exposure to NO2 and the morbidity of lung cancer [2 is mixed with the other outdoor air pollution, it becomes more persistent in terms of explaining the appearance of cancers and could constitute the main cause of SCC [2. Thus, an above-average level of NO2 did not lead to the higher risk of lung cancer. For all other pollutants and cohorts, the risk ratio was always greater than 1, indicating a higher risk of lung cancer for areas of above-average levels of pollutants. The contribution of traffic emissions to ambient air pollution is assessed as individual traffic-related pollutants such as NOollution ,38. In tonfirmed . Howeverg cancer . Our pree of SCC . For the2 exposure and increased lung cancer mortality [2 in women. A particularly significant effect of SO2 on the incidence of lung adenocarcinoma in women was also confirmed by this study (The American Cancer Society Study and the Adventist Health Study indicate a strong relationship between SOortality ,41,42. Tis study .Summing up the conducted causal analyses, it is worth emphasizing that scientific reports with such precise geolocation are rarely encountered, which increases the credibility of linking morbidity with its factors.2 and SO2, and in particular in rural areas in close proximity to an industrial zone, or by recommending a change in residence due to a confirmed carcinogenic effect of the external environment. Thanks to the presented data and the created models enabling the identification of areas with the highest concentrations of selected pollutants, we can now identify those people most at risk of developing lung cancer, broken down by histological subtypes, gender and age.The provided scientific evidence may affect the health of the study population in the future in two ways. In terms of adenocarcinoma prophylaxis: by recommending more frequent check-ups in the risk areas of the Podkarpackie Voivodship with the highest concentrations of PM10, NOThe declining tendency in smoking points to the necessity of focusing on other risk factors. The analysis of these within the context of morbidity and mortality can help to develop more effective screening programs. The present study found significant associations between ambient air pollution and lung cancer.2 and SO2 exposure as air pollutants may increase female lung adenocarcinoma incidence. In men, the increased risk of adenocarcinoma lung cancer is affected by SO2 and PM10. The current study suggests that PM10, NOA high morbidity rate in urban areas and suburbs may be connected with commuting from moderately polluted living areas to highly polluted working areas.


A holographic function screen (HFS) can recompose the wavefront and re-modulate the light-field distribution from a three-dimensional (3D) light field display (LFD) system. However, the spread function of existing HFSs does not particularly suit integral imaging (II) 3D LFD systems, which causes crosstalk and reduces the sharpness of reconstructed 3D images. An optimized holographic function screen with a flat-top rectangular spread function (FRSF) was designed for an II 3D LFD system. A simulation was carried out through ray tracing, which verified that the proposed diffusion function could suppress crosstalk and improve the overall effect. Three-dimensional 3D) light field display (LFD) aims to provide vivid and natural scenes and nature-like 3D simulation environments, and is considered a promising method to reconstruct the light rays’ distribution of a real 3D scene ,2,3,4,5.D light fWith the rapid advances in optoelectronic, electronic, and computer processing technologies, novel components and processing techniques can be used in 3D displays. A holographic function screen (HFS) is a special holographic optical element that combines diffraction and diffusion, which can eliminate the gap between the lenses to guarantee the continuity and uniformity of a reconstructed 3D image. The modulation function and realization method of a HFS are detailed in the literature ,24,25. TIn this study, a HFS with a flat-top rectangular spread function (FRSF) was designed for a 3D LFD, and the overall display effect of the 3D LFD system was simulated by backward ray tracing (BRT) to aid in the evaluation of the proposed HFS. The HFS’ display effects with the conventional spread function and proposed spread function were compared and the suppression of crosstalk and improvement in the overall display effect of the proposed spread function were verified.The schematic diagram of the original 3D LFD system is shown in Therefore, a HFS was introduced into an LFD system. It has been proven that a HFS can modulate the input light field to optimize the display effect. A HFS was placed on the image plane of a MLA, and human eyes focused on the HFS, which greatly reduced viewing discomfort. After being modulated by the HFS, the light incident on the HFS emitted a beam with a certain diffusion angle, which was used to reconstruct the light distribution from the MLA to approximate the light field distribution of the real 3D scene. Through the diffusion effect of the HFS, the effect of the gap on the microlens array to the 3D image was also smoothed. Compared with A holographic function screen (HFS) is a special holographic optical element combining diffraction and diffusion. A HFS can diffuse the incident light at a fixed diffusion angle. In the 3D LFD system, a HFS was placed on the image plane of the microlens array. The light emitted from each lens at different angles diffused into the vertebral body through the HFS, as shown in  regions ; the optThe 3D LFD system based on HFS with a conventional spread function was simulated. OptiX 6.5 was used as the ray tracing engine, and the whole simulation system was divided into two parts, content acquisition and optical reconstruction, as shown in The simulation results are shown in As shown in If the spread function of HFS was changed to reduce the amount of missing information while maintaining the non-aliasing of the reconstructed images, the continuity of the image could be guaranteed and the crosstalk could be suppressed without causing image blur. Therefore, a flat-top rectangular spread function was designed, and a geometric model of the HFS with the rectangular flat-top spread function in the simulation system was established. The closest hit functions of the HFS in the simulation system were changed to achieve different diffusion effects, as shown in The schematic diagram of the simulation system is shown in A verification experiment was conducted to demonstrate the flat-top rectangular diffusion effect of the proposed HFS. In the experiment, a spatial light modulator (SLM) loaded the computer-generated hologram (CGH), and a laser beam illuminated the SLM. A rectangular light spot was obtained on the receiving screen, as shown in The parameters and values used in the simulations are provided in The simulated results using the conventional spread function and the proposed spread function are shown in The 3D LFD display results of reconstructed images (the monkey head) observed from different directions are presented in In summary, to effectively suppress crosstalk and improve the display effect of the 3D LFD system, the spread function of the HFS was analyzed and redesigned. An HFS with a flat-top rectangular spread function (FRSF) was designed. Simulations based on BRT were used to simulate and evaluate the display effect of the 3D LFD system. The SSIM value of the reconstructed 3D image using the redesigned HFS was higher than that reconstructed using the conventional HFS; crosstalk was suppressed and the quality of the reconstructed images was significantly better than those of the conventional HFS, which proved the effectiveness of the proposed HFS.


Carbamazepine (CBZ), a commonly prescribed antiepileptic drug, in human liver, is mainly metabolized by two isoforms of cytochrome P450 (CYP), CYP3A4 and CYP3A5. Therefore, the binding of CBZ with these two enzymes plays crucial role in the biotransformation of the drug into its active metabolite. In the present work, classical molecular dynamics (MD) simulation was used to investigate the detailed interaction mechanism between CBZ and these two CYP isoforms at the atomic level. The results revealed that although CBZ can bind with the two proteins, all kinds of the interactions, including hydrogen bonds, salt bridges, hydrophobic interaction, and π-π interaction, are isoform specific. The specificity directly leads to a binding environment difference at the active sites of the two isoforms, as represented by the electrostatic surface potential maps, which further results in the varied dynamic behavior of CBZ in the two isoforms. Our research will help to deepen the understanding of the physiological functions of CYP isoforms and opens the door for the rational design and development of isoform-specific inhibitors. As a well-known prescribed anticonvulsant medication, carbamazepine (CBZ) has been widely used for the treatment of epilepsy  and trigeminal neuropathic pain in the clinic since it was marketed for the first time in 1962. Furthermore, CBZ is also an adjunctive treatment drugs for schizophrenia and acute mania, as well as a second-line drug for bipolar disorder and borderline personality disorder ,4,5,6,7.In the human body, the main organ for CBZ metabolism is the liver which is responsible for more than 95% of the drug’s degradation . Two memCYP3A4 and CYP3A5 are closely related in both structure and function . First, www.rcsb.org (accessed on 15 May 2022)), with the corresponding PDB IDs of 5TE8 and 5VEU, respectively. The original ligands in the two crystal structures, except the heme groups, were deleted to construct the ligand-free systems of the isoform proteins. The substrate CBZ needed in the research was manully sketched in Discovery Studio 3.1 package and then docked into the active site of two isoform proteins using the CDOCKER docking algorithm, thus leading to the holo forms of two CYP proteins [The atomic coordinates of two isoforms CYP3A4 and CYP3A5 for the construction of the simulation systems were obtained from the Protein Data Bank  values of the protein’s alpha carbon (Cα) atoms in four systems were used for the evaluation of the stability of the protein and substrate structures by taking the initial coordinates of the selected atoms in each systems as the references. The obtained RMSD profiles are shown in The effect of the substrate CBZ’s binding with the proteins on the flexibility of each protein residue could be characterized by the root-mean-square fluctuation (RMSF) of the residues . CompariIn the production phase of the conventional MD simulation, the substrate CBZ was always located in the active sites of the CYP isoforms CYP3A4 and CYP3A5 . It can From In terms of the salt bridge, the substrate CBZ had no salt bridge interaction with any CYP isoform or the heme group. However, the salt bridges between some residues of the two proteins can affect the binding of the substrate CBZ in the active site. It can be seen in As the substrate CBZ molecule contains two aromatic rings, the hydrophobic interaction of the two atom groups with the surrounding environment (including protein’s residues and heme group), especially the π-π interaction, plays crucial roles in the binding of CBZ with proteins and its catalysis by the isoforms. The hydrophobic interaction, along with the π-π interactions, for the representative conformations in the dynamic binding of CBZ with the two CYP isoforms is shown in detail in From the above analysis, it can be seen that the active sites of the two isoforms have different residue composition, which gave rise to the varied behaviors of the substrate CBZ in the respective binding sites during the MD simulation. In order to further reveal these differences, the electrostatic surface potential of the CYP proteins in the two isoform-CBZ complex systems is displayed in Conventional molecular dynamics method was used to the research the binding of the anticonvulsant CBZ with two CYP isoforms, CYP3A4 and CYP3A5. The simulation results showed that the substrate CBZ can stably locate in the active sites of the two proteins in the whole MD stage. However, according to the atomic-level analysis, the detailed interaction between CBZ and the protein residues is different in the two isoforms, including a hydrogen bond, the salt bridge, hydrophobic interaction, and π-π interaction analysis, which also leads to the different dynamic behaviors of the substrate CBZ in two isoforms. The electrostatic surface potential maps of the proteins in two complex systems directly and significantly represent the different binding environments of the substrate CBZ in the active sites of the two isoforms. Therefore, the residue compositions in the active sites of two CYP enzymes, forming the different binding environments, is the fundamental reason for the difference of the dynamic behaviors of the substrate CBZ.


Objectives: To analyze the stress distribution in the proximal vertebral body and soft tissue of dual growing-rod (GR) with different upper instrumented vertebra (UIV) to determine the optimal UIV.Methods: A ten-year-old male EOS case treated with GR was selected. Based on spiral computed tomography (CT) scanning performed in 0.6 mm thick slices, a finite element model (FEM) of the preoperative state  of the patient was created. Subsequently, four models with different UIV fixations were numerically analyzed by FEM, including M1  of the upper thoracic curve), M2 (UIV = T2), M3 (UIV = T3) and M4  of the upper thoracic curve). Displacement and maximum stress in the proximal vertebral body and soft tissue were measured and compared among the five models.Results: The spine model was fixed with the sacrum, and the gravity conditions were imposed on each vertebral body according to the research of Clin and Pearsall. The results are as follows:M4 model has the largest overall displacement, while M1 has the least displacement among the four models. Except M2, the maximum normalized stress of UIV increases with the downward movement of UIV. M1 has the lowerest annulus fibrosus stress and highest joint capsule stress, which is characterized by the vertebrae backward leaning, while M4 is the opposite. The supraspinous ligament stress of M3 and M4 is significantly higher than that of M1 and M2. This suggests that UIV downshift increases the tendency of the proximal vertebral bodies to bend forward, thereby increasing the tension of the posterior ligaments (PL).Conclusion: The UIV of the GR is recommended to be close to the UEV of the upper thoracic curve, which can reduce the stress of the proximal PL, thereby reducing the occurrence of proximal junctional kyphosis (PJK). Early-onset scoliosis (EOS) referred to as the spinal deformities in patients under 10 years of age is a complex spinal diseases difficult to solve . During Among the current treatment methods of EOS, the growing-rod (GR) technique, which can maximize the potential growth of the spine and deformity correction has gained great success . HoweverThe risk factors of PJK are mainly obtained from the retrospective study of clinical cohorts, making it difficult to directly use cadavers for experiments since the samples will gradually produce operating errors during repeated percedure . AlthougThus, the C1-S1 full-spinal models of EOS patients with dual growing rod were established in the present study. The stress distribution of the proximal vertebral body and soft tissue at different levels of dual growing rods fixation was simulated by the finite element method, and the risk of PJK was analyzed, ultimately to explore the optimal upper instrumented vertebrae (UIV) of the growing rod.A 10-year-old patient with early-onset scoliosis  was selected. The patient underwent single growing rods surgery with T3 as the UIV and L4 as the lower instrumented vertebra (LIV) . The scoThe geometry was reconstructed by 3D CT-scan images (slice thickness: 0.6 mm) from the patient, ranging from C1 to S1 segments. The CT tomographic data were stored in standard Dicom format.The extracted Dicom file was imported into Mimics Research 21.0 , and the bone boundary was extracted through threshold segmentation. Each segment of the vertebra was acquired with filling and splitting and saved as a different Mask. The reconstructed vertebras were saved in STL format. The model surface was smoothed, meshed, and converted to a STEP solid model with Geomagic Studio . The C1-S1 segment model in STEP format was imported into Solidworks 2019  to simulate surgical correction according to the patient’s postoperative radiographs. Subsequently, cortical and cancellous bone were divided, and the intervertebral disc and facet joint capsule were established, where the intervertebral disc contained the annulus fibrosus and nucleus pulposus. The proportion of nucleus pulposus was between 30% and 50%. The thickness of cortical bone was 1 mm.2.The established C1-S1 segment geometric model of the spine was imported into HyperMesh 2019  for FEM establishment. Vertebrae, intervertebral discs, and joint capsules were defined as elastic, with material properties defined in terms of elastic modulus and Poisson’s ratio . The modDual growing rod fixation was adopted with four screws at the upper and lower end. The lower four screws are located at L3 and L4. Four post-orthopedic models, M1 (UIV = 1), M2 (UIV = 2), M3 (UIV = 3), M4 (UIV = 4), and one pre-orthopedic model M0 were established according to the different positions of the upper screws . In addiTo validation the numerical simulation procedure, the average stiffness of spine segments without growth rods under the same load were compared with the literature . The aveIt can be seen from the table that the biomechanical properties of the T1–T4 segments of the spine model established in this study are not significantly different from those of the spine model in the previously recognized literature. Because the whole spine segments and the T1–T4 segments use the same modeling method and material properties, the model of the full-segment spine can be considered valid and can be used for further analysis.The overall displacements of the M0–M4 model are shown in The stress nephogram of the M1 model is shown in The GR fixation system had maximum stress of 162.8 MPa occurring on the pedicle screw. However, the stress was far from causing fracture to the fixation system. As the UIV position was shifted inferiorly, the maximum Von Mises stress of the pedicle screw did not show the same trend as that of UIV and UIV+1. The maximum fixation stress of the M3 model was larger than that of other models. While the maximum value of UIV stress of M2 and UIV+1 stress of M4 are the largest.The spatial position and stress concentration area of different vertebrae were completely different. UIV and UIV+1 in M1–M4 were not in the same position, which made it difficult to compare with each other. Therefore, normalization was necessary to be performed before comparison. The normalized method was to reconstruct an orthopedic spinal model (MC) without any fixation and simulate it in the light of the same pre-processing. The maximum Von Mises stress of UIV and UIV+1 of M1–M4 was divided by the maximum stress of the corresponding vertebral body of MC to obtain the normalized results of stress.The normalized maximum value of UIV and UIV+1 stress are shown in According to the stress changes of the vertebral body, the dual growing rods and pedicle screw fixation system can increase the stress of UIV and reduce the stress of UIV+1. The stress distribution of the vertebral body is shown in The stress distribution results were better than other groups when UIV was T1. M1 was a better solution because not only was the maximum stress of UIV almost unchanged before and after fixation but there was no stress concentration on the upper and lower surface of the vertebral body. Excluding M2, the maximum normalized stress value of UIV increased with the downward movement of UIV, while the value of M2 was close to that of M4, which may be related to the spinal curve of the case.The annulus fibrosus and joint capsule stresses associated with UIV and UIV+1 were also compared. . The stress of ISL after normalization was significantly lower than that of SSL before fixation with growing rods, with ISL stress of 5.4%–7.7% and SSL stress of 4.6%–16.9%. The difference between groups was significant. The ISL stress variation of M1–M3 was similar, while the stress of M4 was lower. The SSL of M1 and M2 were almost free from stress with the influence of growing rods, but the SSL stress of M4 was the largest.The normalized stress of the interspinous ligament (ISL) and supraspinous ligament (SSL) is shown in EOS is a spinal deformity with the characteristic of early occurance, rapid progression, and continuous growth of the spine, with a significant risk of cardiopulmonary insufficiency . Patientin vivo and in vitro experimental studies, such as stress distribution and displacement under static conditions  consists of ISL, SSL, and facet capsular ligaments, which play an important role in maintaining spinal stability and limiting the normal range of movement of the spine . Some reOur study has several limitations. First, the EOS spine FE model was developed based on the geometric information of the spine from a single EOS patient, which cannot calculate the statistical significance. Then, the paraspinal muscles were not constructed in this model, although a widely recognized physiological follower load was applied to simulate the effect of muscle force . NeverthIn the current study, the stress distribution in the proximal vertebral body and soft tissues of dual growing rods with different proximal fixation segments were analyzed using FEM to explore the optimal UIV. The results showed that the stress of the vertebra and soft tissue at M1 was the lowerest, and the fixed condition could conquer the PJK formation and progression. M4 model, on the contrary, is more likely to cause PJK occurrence. Therefore, PJK is less likely to occur when the upper end of the dual growing rods is fixed close to the UEV of the upper thoracic curve.


This article describes the use of recycled glass sand in the production of autoclaved products. Traditional autoclaved bricks consist of crystalline sand, lime and water. The conducted research aimed at the complete elimination of quartz sand in favor of glass sand. This work focuses on porosity as the functional property of the materials. The aim of this article is to determine the number and structure of the pores of autoclaved bricks. Two types of research were carried out: (a) non-destructive, i.e., computed tomography examination as a pictorial and quantitative method and (b) mercury porosimetry as a quantitative method, i.e., a test that exposes the porous skeleton of the material for destruction. The tests showed the presence of pores with a size in the range of 0.1 ÷ 100 μm, and the volume of voids in the material was determined at the level of about 20% for the sample modified with glass sand (GS) and for the reference sample made of traditional silicate brick. In order to complete the research on the internal structure of autoclaved bricks, microstructure studies were performed using a scanning electron microscope (SEM). The tests showed the presence of tobermorite in the reference sample (with 90% QS-quartz sand) and the presence of natrolite and gyrolite in the sample modified by glass sand (90% GS). This article deals with the topic of sustainable construction in the context of ecology and material deficits. This work is a continuation of considerations on the possibility of using glass sand from glass recycling in materials resulting from hydrothermal treatment, i.e., subjected to conditions of increased pressure and temperature ,2,3 (a t(1)2·K) [3) [The production process of silicate bricks takes a maximum of 8 h, after which we obtain a brick with a strength of 15–20 MPa, from which buildings of up to five floors can be made. This type of bricks is a natural building material intended for the construction and partition walls with a heat transfer coefficient (U) in the range of 0.46–0.72 W (m2·K) , which i2·K) [3) . Such ti(2)2O content). Thus, in terms of thermodynamic considerations, silicate bricks are more stable and resistant to weather conditions . The C-S-H phase is metastable and retains its properties up to temperatures of 25–30 °C. The analysis of the pore content in concrete is also important since it is believed that the formed pores can serve as an effective protection against the harmful effects of frost [−1 and the minimum air content in the pores is smaller than 0.3 mm (A300) by at least 1.5%. The basic method of examining the concrete’s structure is a qualitative image analysis of it, followed by computer image analysis, leading to quantitative results [The difference in the microstructure of the materials produced, i.e., the structure of the concrete, by about 70%, consists of the amorphous C-S-H phase, capable of crystallization, while the structure of silicate bricks consists of 90% (by mass) tobermorite crystalline phase  and/or gyrolite or natrolite  [(1)Green economy contributing to solving social problems in a sustainable manner, including, in particular, poverty eradication;(2)Institutionalization of global cooperation for sustainable development, which is to lead to a greater harmonization and effectiveness of these activities . ParticiThe biggest problem of the construction industry is the excessive use of natural aggregates for the construction of new facilities, which is related to the so-called overproduction and excessive consumption of natural aggregates, including quartz sand, and the further heating of buildings with solid fuel along with the development of the refining industry, which leads to progressive climate change  ,35,36,372 emissions to the atmosphere to fight the aforementioned material overproduction. The current requirements for the heat transfer coefficient U (m2·K) for materials are presented below. This coefficient depends on the porosity of the material [2·K), roof: 0.15 W/(m2·K), floor on the ground: 0.3 W/(m2·K)) [The declaration from the Earth Summit in Rio De Janeiro in 1992 already informed about the abuse and the resulting depletion of natural resources, but the rapid changes could not be brought under control. This was related to the years of occupation and wars that took place in the 20th century, after which countries, including Poland, had to rebuild and reorganize. Faced with unfavorable past experiences and challenges in the future, the construction industry is expected to change. Some of these changes can be stopped, others not. Therefore, the modification of materials today should be approached carefully, both from an ecological and economic point of view. An important factor of the 21st century is spreading awareness about recycling and fighting to improve environmental conditions to reduce energy losses related to, among others, heating buildings, hence reducing COmaterial ,39,40. Cmaterial ,39 for bTwo types of research were carried out on the internal structure of porous material: CT computer tomography and mercury porosimetry. The tests were carried out in accordance with the intended use of the described equipment (paragraphs above) and on the basis of the following standards: PN-EN 772-13: 2001, CEN. PN-EN 1996-2, CEN. PN-EN 771-2 and PN-EN 1936: 2010, PN-EN 993-1: 2019-01 ,42,43,442O) in the presence of sand (SiO2) was 86 °C for the reference mass (with QS) and 42 °C for fully modified GS bricks.Tested materials consisted of a low binder content (7% lime by mass) and were abundant in silica up to 90% by mass modified with broken amorphous glass. Glass sand (GS) is characterized by a high sodium content. The presence of aluminum in the sample may affect the swelling of the material; therefore, an important aspect of the test is to perform the elemental composition analysis to acquire data on the amount of aluminum compounds in the tested material. The analyzed samples were manufactured in 2015 and the process of changes in the materials were observed. This process is important because glass sand is metastable . It was shown that the crystallization proceeded toward natrolite and gyrolite, which is justified by the presence of sodium ions coming from the recycled glass. The sample was stored at a temperature of 23–26 °C for the entire period . The compressive strength of laboratory samples for brick modified by glass sand (GS) was 20 MPa. The hydration temperature of the binder (CaO) with water  a. The inPorosity tests were performed using a QUANTACHROME ULTRAPYC 1200e helium pycnometer  on irregularly shaped samples weighing approximately 10–25 g b. The heMicrostructure analysis was performed on a Quanta Feg FEI Company scanning electron microscope .The tomographic examination of samples of autoclaved materials included scanning the material a, digitaMercury intrusion porosimetry (MIP) is one of the basic research methods used for determination of pore structure, size and pore distribution. This method is based on the experimental determination of the so-called capillary potential curve (capillary pores) linking the volume of mercury pressed into a porous material sample with the pressing pressure . The staThe tests were used to determine the distribution and number of pores in the tested materials as well as their pore geometry. Simultaneously with the mercury intrusion porosimetry and Micro-CT analysis, the material was analyzed using a scanning electron microscope. Photos from the measurements of the samples are presented on the plane and in space as images of the distribution and size of air pores in the analyzed area of the tested material.Computed tomography was used as a form of imaging the arrangement and shape of the pores, and then a study was carried out to determine the porosity of the materials. Under the influence of microstructural changes , the porosity changes. The CT scan was performed with a reflection lamp (reflection target). The maximum capacity of this lamp is 225 kV and 225 W. The scan was made without a filter at 180 kV and 139 uA current. The exposure time was 250 ms. A total of 4476 projections were made and assembled into a 3D model. Each projection was generated with four frames per projection. The size of the voxel, i.e., the resolution, was 15 μm. All the parameters were selected experimentally to ensure the best image quality. During the CT scan, the pores were determined using the porosity/inclusions analysis tool in VG Studio Max. In order to separate the material from the voids, the value of the so-called voxel gray threshold was defined . All voxels corresponding to the darker areas were identified and counted, thus obtaining the percentage and volume pore content of the entire sample volume as well as the volume of each individual pore. Pores with diameters smaller than the obtained resolution cannot be detected. The pores were sorted by volume and presented on a 3D model in a self-selected color scale. Blue-color pores correspond to pores in smaller volumes, while red ones correspond to higher volumes .3, while in the sample modified with recycled glass sand, it represented 0.8%, i.e., 2.5 mm3. The photos  and more air pores are present in the material modified with glass sand. The obtained difference may be due to the fact that the computed tomography method included a 3D analysis, and the obtained values were calculated on the basis of measuring the actual diameters of air voids in the tested element and the cross-section. The outer texture of the porous silicate material, on the other hand, was characterized by greater hardness and was less susceptible to mechanical damage. This difference may be associated with the fact that quartz sand is less reactive because it has a higher Mosh hardness (7) and can scratch glass . The mate photos  show imae photos  as a repThe photo  shows boThe photos  show thaPhoto 14 shows an image of the microstructure of a reference . The compounds and impurities found in both quartz sand and glass sand are important during the synthesis and crystallization of the phases. For example, aluminum influences the formation and synthesis of the tobermorite phase, thus reducing the specific surface area. The glass cullet, in turn, causes the crystallization of the C-S-H phase toward natrolite and gyrolite. It is now important to examine the amount of crystalline and amorphous phases in the tested bricks (percentage or weight) and the quality of these phases. The next step of this research will consist in determining the changes in the microstructure of the material modified with glass sand after 5 and 7 years from the date of their production in 2015. A geochemical equilibrium-based simulation will be performed using the GEMS-PSI program, and the samples will be re-examined using a computer tomograph (after another 12 and 24 months). The pore space of the autoclaved materials  will also be examined by the Archimedes method.The materials covered by this study were silicate bricks with a traditional composition and silicate bricks modified by glass sand in the amounts of 0% , 50% quartz sand, 50% recycled glass sand and 90% recycled glass sand .The important task of this article was to present a non-destructive method in the form of computed tomography to visualize porous materials, such as silicate bricks.3, while in the sample modified with recycled glass sand, it represented 0.8%, i.e., 2.5 mm3. Both methods can be compared with each other and give relatively reliable results; however, non-destructive computed tomography can be performed many times without disturbing the structure and skeleton of the tested material.Using computed tomography, two types of bricks were examined: traditional (reference) sand-lime bricks, the main component of which was quartz sand (90%), and bricks entirely modified with glass sand from recycled glass (90% GS). The experiment was to show how the pores are arranged in the traditional (reference) sand-lime brick as well as in the brick modified with glass sand, as well as the difference in the microstructure of both materials. The computed tomography examination was compared with the mercury intrusion porosimetry examination. The porosimetry method is widely used to analyze porous materials, but studies have shown that this method can damage the internal skeleton of the material by violently and forcefully acting on the sample with mercury under pressure. The analysis of the voids in the traditional silicate brick sample treated as the reference value showed that a pore content below 300 µm represented 0.02%, i.e., 0.06 mm


A protective effect of C60 on the biomechanics of fast (m. gastrocnemius) and slow (m. soleus) muscle contraction in rats and the pro- and antioxidant balance of muscle tissue during the development of muscle fatigue was studied compared to the same effect of the known antioxidant N-acetylcysteine (NAC). C60 and NAC were administered intraperitoneally at doses of 1 and 150 mg kg−1, respectively, daily for 5 days and 1 h before the start of the experiment. The following quantitative markers of muscle fatigue were used: the force of muscle contraction, the level of accumulation of secondary products of lipid peroxidation (TBARS) and the oxygen metabolite H2O2, the activity of first-line antioxidant defense enzymes (superoxide dismutase (SOD) and catalase (CAT)), and the condition of the glutathione system (reduced glutathione (GSH) content and the activity of the glutathione peroxidase (GPx) enzyme). The analysis of the muscle contraction force dynamics in rats against the background of induced muscle fatigue showed, that the effect of C60, 1 h after drug administration, was (15–17)% more effective on fast muscles than on slow muscles. A further slight increase in the effect of C60 was revealed after 2 h of drug injection, (7–9)% in the case of m. gastrocnemius and (5–6)% in the case of m. soleus. An increase in the effect of using C60 occurred within 4 days (the difference between 4 and 5 days did not exceed (3–5)%) and exceeded the effect of NAC by (32–34)%. The analysis of biochemical parameters in rat muscle tissues showed that long-term application of C60 contributed to their decrease by (10–30)% and (5–20)% in fast and slow muscles, respectively, on the 5th day of the experiment. At the same time, the protective effect of C60 was higher compared to NAC by (28–44)%. The obtained results indicate the prospect of using C60 as a potential protective nano agent to improve the efficiency of skeletal muscle function by modifying the reactive oxygen species-dependent mechanisms that play an important role in the processes of muscle fatigue development.C 60 fullerene; N-acetylcysteine; m. soleus; m. gastrocnemius; Muscle fatigue; Biomechanical and biochemical parameters.С TherDuring the development of fatigue, there is a slowdown in force generation and muscle relaxation . SkeletaOxidative stress is a generally recognized pathophysiological factor in the formation of muscle fatigue and overexertion under conditions of excessive physical activity . There aDuring the intensive physical activity of skeletal muscle, lipid peroxidation (LPO) is the primary reaction in the chain of physicochemical transformations that lead to the destruction of the lipoprotein complex of myocyte membranes, disruption of their transport functions, inhibition of oxidative phosphorylation processes, and energy generation, which ultimately reduces cell viability and contributes to muscle fatigue . However60 fullerenes .Yuriy Prylutskyy was supported by Data will be made available on request.The authors declare no competing interests.No additional information is available for this paper.


Recently, various efforts have been made to reduce the environmental burden caused by semiconductor manufacturing by improving the process efficiency. Chemical mechanical polishing (CMP), which is used to planarize thin films in semiconductor production, has also been studied to improve its efficiency by increasing the material removal rate (MRR) while reducing its environmental burden. Previous studies have been conducted to electrolytically ionize chemical solutions used in abrasive-free CMP for improving the MRR. In this study, we analyzed the change in the chemical solution according to the variation in voltage applied to the nickel (Ni) electrode in abrasive-free Cu CMP and studied the tribological material removal characteristics. The experimental results revealed that electrolytic ionization of the chemical solution for abrasive-free CMP increases the amount of dissolved oxygen (DO). The static etch rate of the Cu thin film and MRR in CMP increased as the voltage applied to the Ni electrode increased. The frictional force and temperature during CMP also increased as the applied voltage increased. Therefore, the increase in MRR caused by the increase in the applied voltage in abrasive-free Cu CMP using electrolytic ionization is plausibly caused by the chemical reaction between the dissolved oxygen in the chemical solution and Cu. With the high integration of semiconductors, chemical mechanical polishing (CMP) technology has developed remarkably, and its application scope is gradually expanding ,2,3. Rec2O2) and showed that the material removal rate (MRR) could be controlled by adjusting the content and pH. Oxalic acid and H2O2 were used as complexing and oxidizing agents, respectively. Their study demonstrated the highest MRR in an abrasive-free Cu CMP solution with pH of 3–4. Ramakrishnan et al. [Some researchers have proposed a method using an abrasive-free slurry for resolving defects that may be caused by abrasive particles in CMP. Abrasive-free CMP has been studied for planarizing a Cu film because the chemically reactive layer on the surface of Cu can be removed by the asperities of the polishing pad by adjusting the chemical composition of the abrasive particle-free slurry. Hanazono et al.  reportedn et al.  used dicn et al.  stated tn et al.  proposedDeNardis et al. ,12 conduAnother method for improving the MRR of CMP is the electrolytic ionization of the slurry by applying electrical energy. Lee et al.  conducteExisting CMP studies that use slurry electrolytic ionization primarily use stainless steel as an electrode material. The change in the chemical solution through electrolytic ionization has not been investigated. In this study, nickel (Ni), exhibiting higher conductivity than stainless steel, was used as an electrode material, and the change in the chemical solution used in abrasive-free Cu CMP, depending on electrolytic ionization, was studied. A tribological study was conducted on the MRR, friction force, and pad temperature changes based on the voltage applied during the abrasive-free CMP using electrolytic ionization. In addition, to investigate the material removal characteristics of abrasive-free Cu CMP using electrolytic ionization, the amount of dissolved oxygen in the slurry was measured, unlike in previous studies.A CMP system for R&D  was used, and an electrolytic ionization device for the chemical solution using Ni plates was placed at the end of the nozzle . The dim2O2, citric acid, and benzotriazole (BTA). H2O2, citric acid, and BTA act as an oxidizer, complexing agent, and corrosion inhibitor, respectively. The concentration of each component of the CMP solution is listed in The CMP solutions used in the experiment included deionized water (DIW), HThe change in thickness of the Cu thin film was measured using a 4-point probe . The CMP MRR was expressed as the change in the thickness of the Cu thin film removed for 1 min, and the within-wafer non-uniformity (WIWNU) was the percentage obtained by dividing the standard deviation (STD) of the MRR, measured at 19 points in the wafer radius direction, by the average MRR.A square coupon wafer (30 × 30 mm) was immersed in an electrolytic ionized chemical solution for 5 min and the static etch rate of the Cu thin film was measured. Surface chemical analysis was performed using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) . The change in thickness of the Cu thin film was measured at five points on the coupon wafer. To confirm the change in the electrolytically ionized CMP solution, the amount of dissolved oxygen after electrolytic ionization was measured.In the CMP experiment, 4-inch wafers were used and 1 μm of sputtered Cu was deposited on the Ti barrier (50 nm). A hard polyurethane polishing pad  was used. The CMP experimental conditions are listed in 2O), cupric oxide (CuO), and cupric hydroxide (Cu(OH)2). The binding energies of metallic Cu 2p1/2 and Cu 2p3/2 were approximately 952.3 and 932.6 eV, respectively. The binding energies of metallic Cu, CuO, Cu(OH)2, and Cu2O have been reported to be approximately 932.6 [2 was lower than that of the as-received Cu, whereas an increase in the intensity of the Cu2O and CuO peaks was observed. At 30 V (2O and CuO peaks were higher than those of the as-received Cu and those at 0 V. According to the Cu CMP mechanism, the Cu surface is oxidized by the oxidizer in the slurry and Cu ions are generated, and the etching of Cu occurs by combining the complexing agent and generated Cu ions. ly 932.6 , 933.5 ±ly 932.6 ,19,20, 9ly 932.6 , respect At 30 V c, the CuPrevious studies on CMP using electrolytic ionization explained the CMP mechanism through the analysis of chemically reacted surfaces, but the change in dissolved oxygen due to electrolytic ionization was not considered. Imai et al.  investig2 gas atmosphere during Cu CMP. Jo et al. [2 gas. The CMP method, which uses electrolytic ionization, increases the amount of dissolved oxygen through electrolytic ionization of a chemical solution instead of directly injecting O2 gas.o et al.  used an The friction force  and poliIn the CMP process, directly measuring the frictional heat generated at the interface between the wafer and pad is difficult. However, it can be identified indirectly by measuring the pad temperature near the trailing edge of the wafer. The average temperature of the polishing pad before CMP was 21.2 °C, and as CMP progressed, the pad temperature near the trailing edge of the wafer continued to increase. The average temperature of the polishing pad tended to increase as the applied voltage increased, and the average temperatures were 28.6, 29.1, 29.7, and 30.4 °C for 0, 10, 20, and 30 V, respectively. The increases in the polishing pad temperature were 10.0, 10.5, 10.9, and 11.5 °C at 0, 10, 20, and 30 V, respectively. The increase in the friction force with increasing applied voltage was attributed to the formation of a chemically reactive layer owing to the increase in dissolved oxygen in the chemical solution. The polishing pad temperature is thought to be a result of the interfacial friction between the polishing pad and wafer. An increase in process temperature during CMP promotes the chemical reaction of the slurry.As a result of observing the change in the chemical solution for abrasive-free Cu CMP and analyzing the CMP experiment results according to the increase in the applied voltage, electrolytic ionization of the chemical solution seems to improve the chemical reactivity by increasing the dissolved oxygen in the solution. The chemically reactive layer on the copper surface generated by the activation of the chemical solution appears to be removed by mechanical friction owing to the asperities of the polishing pad.In this study, abrasive-free Cu CMP using electrolytic ionization with a Ni electrode was investigated. A change in the chemical solution was observed with an increase in the applied voltage. In this study, changes in the amount of dissolved oxygen and the chemical composition of Cu according to the electrolytic ionization of the chemical solution were investigated. When electrolytic ionization of the chemical solution was achieved, the dissolved oxygen in the chemical solution increased through electrolytic ionization. The increased dissolved oxygen in the chemical solution promotes a chemical reaction with Cu, increasing the static etch rate of Cu and leaving a chemical reaction layer. As the voltage applied to the electrode increased, the MRR of Cu, frictional force, and temperature during processing also increased. This result appears to be because a reactive layer that is easily removed mechanically is formed on the surface of Cu through electrolytic ionization of the chemical solution, and as the applied voltage increases, the asperities of the polishing pad remove the reactive layer.Although an Ni electrode was used in this study, more research on various electrode materials is needed in the future, and the design and optimization of a nozzle for electrolytic ionization are required. In addition, studies applying the CMP method using electrolytic ionization to the planarization of various materials that require longer processing times should be conducted.


On the other hand, there was a reduction in EI in EG6S at the end of the intervention program (p = 0.021), and both experimental groups increased EI in the three regions of interest analyzed after the detraining period (p < 0.01). In conclusion, the execution time of the eccentric contraction in the SLDS exercise determines the anatomical level of the morphological adaptations in the PT. These morphological adaptations are lost after 6 weeks of detraining, producing an increase in tendon stiffness.The purpose of this study was to assess the effects of eccentric contraction execution time on the morphological and elastic properties of the patellar tendon (PT) in a six-week, single-leg decline squat (SLDS) exercise training program. In addition, the effects of a six-week detraining period on the same variables were evaluated. Fifty participants were randomized into the control group , experimental group 1  and experimental group 2 . The thickness and elastographic index (EI) in different regions of interest (ROIs) in the PT were measured after 6 weeks of eccentric training using the single-leg decline squat exercise  and after 6 weeks of detraining. There was an increase in the thickness of the PT in the different ROIs analyzed in both experimental groups at the end of the training period. Especially worth noting was the increase in the thickness of the PT at the proximal level in EG3s ( The patellar tendon (PT) originates from the distal two-thirds of the patella and generally inserts at the most distal end of the anterior tuberosity of the tibia, where it joins the fibrillar expansions of the iliotibial tract . Three vEccentric exercise is frequently used in physiotherapeutic interventions for the treatment of patellar tendinopathy . SpecifiMovement speed during eccentric training alters important factors involved in muscular adaptations, such as time under tension and muscle activation ,16. BurdFifty-four healthy physical education students voluntary participated in this study. Eligible participants were physically active  and between 18 and 35 years old. All participants scored > 90 points on the Victorian Institute of Sport Assessment-PT questionnaire (VISA-P) in its version translated to Spanish (VISA-P-Sp)  to excluParticipants were randomly divided into three groups: (1) the control group  with no intervention program; (2) experimental group 1  which followed the intervention program performing the SLDEe in 6 s; and (3) experimental group 2  which followed the intervention program performing the SLDEe in 3 s .All participants were informed about the objective and methods of the investigation and signed the informed consent forms before the start of the study. Ethical approval was obtained from the Ethics Committee of Clinical Research at the Hospital Complex in Toledo (Spain) (62-100615) according to the principles of the latest version of the Declaration of Helsinki.A three-group parallel repeated measures design was carried out to examine the thickness and elastography index adaptations of the PT in response to two SLDSe training programs performed with two execution times (6 s vs. 3 s). In week −1, the participants were selected and the VISA-P-Sp questionnaire was filled out. In week 0, two sessions were carried out. In session 1, the first assessment (PRE) was made before the intervention program (these data were used as baseline measures) and the anthropomorphic measures were recorded. Participants were then notified of their allocated training group and familiarized with the eccentric SLDSe exercise and with the 5 repetition maximum (RM) test of their corresponding exercise-specific training program . In session 2 (72 h after session 1), the 5 RM test of the SLDSe exercise for EG6s and EG3s in the dominant limb was performed in order to determine the training load.From weeks 1 to 6 the participants completed a 6 week eccentric program. Each session was carried out with the principal investigator and two collaborators to ensure adherence and the correct technique. In week 7, the second measurement was performed at the end of the intervention program (POST-1) and in week 14, the third measurement was performed, 6 weeks after the intervention finished (POST-2) to evaluate the consequences after a 6 week detraining period .The intervention program of the SLDSe training for both groups (EG6s and EG3s) lasted 6 weeks. Three training sessions were carried out every week at least 48 h apart. Three sets of 8 repetitions were performed in each training session (the rest duration between repetitions was 6 s and between sets was 2 min) of the SLDSe exercise previously described  with thewww.webmetronome.com; accessed on 5 February 2019) was employed to establish the start and the end of the eccentric phase in each group.The eccentric phase of movement of each repetition lasted 6 s in EG6s and 3 s in EG3s. The 1 RM of the SLDSe for each experimental group was calculated before the start of the training program (in week 0) and just after the training in weeks two and four to recalculate the training load. Participants were trained to complete the back-squat exercises with the trunk in a vertical position in a multipower machine . Both experimental groups were trained to perform the exercise by slowly bending the knee to 90° of flexion and, in order to focus only the eccentric loading of the quadriceps and to return to the initial position, the participants were trained to use the non-dominant lower limb in addition to the dominant one and two assistants lifted the weights to prepare them for the next repetition. Thereby, we decreased the influence of the concentric phase of the anterior thigh muscles. A metronome , with two parallel straight bars that only allowed vertical movements. The participants were trained to position themselves under the shoulder bar of the multipower rack machine. A specific warm-up routine was carried out using the weight of the bar (~18 kg), the participants performed two sets of twelve eccentric repetitions, and one minute rest. Each of the eccentric repetitions was carried out by the two experimental groups in a time of 6 s (EG6s) or 3 s (EG3s), reaching up to 90° of knee flexion, which was assessed with a goniometer placed on the knee joint, and resting for 6 s between each repetition. After 2 min of rest, the test was carried out with the participants performing a series of 5 eccentric repetitions with increasing intensity, starting with the weight registered in the pre-testing. The load was increased until the 5 RM was determined with a 2 min rest between sets. If the subject did not keep the execution speed of the movement or did not reach 90° of knee flexion, the repetition was considered invalid. In the event that the participants could not perform the repetition due to fatigue or inability to endure the weight, the weight lifted in the last series of 5 RM was recorded. Afterwards, the 5 RM was converted to 1 RM ,21.The thickness of the PT was measured by B-mode ultrasonography  with a 5.5 cm, high frequency 6–15 MHz linear probe. The participants lay supine on a stretcher, with the knee flexed to 15° ,22. The The elastographic index (EI) of the PT was evaluated in three ROIs . Then, the main effects of the two training interventions were determined by a two-factor (3 × 3) mixed-model ANOVA. The first factor was the group  and the second factor was the timeline . Effect size (ES) statistics were calculated according to the formula proposed by Cohen [p < 0.05 for all statistical analyses. The data were analyzed with the statistical package IBM SPSS Statistics 23.0 . The normality of each variable was initially tested with the Shapiro-Wilk test. All the variables presented normal distributions  except between CG and EG3s in the thickness of PT at 50%. Additionally, in the CG, no significant differences were found between the measurements obtained at PRE, POST-1 and POST-2 tests in any of the dependent variables. No significant differences were found in the length of the PT between PRE, POST-1 and POST-2 evaluations in any of the groups.p < 0.001, ES = 3.8 and EG3s: difference = 100.5 ± 33.7 kg; CI 95%: from 84.5 to 116.5 kg, p < 0.001, ES = 3.9) and a decrease after 6 weeks of detraining was found in EG6s  95%: from −43.0 to −18.6 kg, p < 0.001, ES = 0.8) and EG3s . No significant changes in the 1 RM were found in the control group.A significant increase was found after 6 weeks of eccentric training in the 1 RM in both experimental groups  95%: from 73.2 to 106.2 kg, p = 0.015, ES = 0.4) greater in EG3s after 6 weeks of eccentric training and a decrease after a 6 week follow-up was found in EG3s (p = 0.005). A significant increase was found after 6 weeks of eccentric training in the thickness of the PT at 25% in both experimental groups  and a decrease after 6 weeks of detraining was found in EG6s (p < 0.001) and EG3s (p < 0.001). The values in the thickness of the PT at 50% and 75% were greater in EG6s (p < 0.001) and EG3s  after 6 weeks of eccentric training. Significant decreases (p < 0.05) were found after the six weeks of non-training compared to POST-1 in the thickness of the PT at 50% (EG6s: p < 0.001) and 75% .The values obtained for the length and the thickness of the PT in the different zones analyzed are shown in p < 0.001, ES = 0.5) greater after the 6 weeks of eccentric training compared to the baseline and a decrease from POST-1 was found after 6 weeks of detraining . The thickness of the PT in the anterior tuberosity of the tibia in EG6s was 0.05 ± 0.04 cm  in the EI at 25% of the PT were found after the six weeks of non-training compared to PRE evaluation  and compared to POST-1 . A significant increase (p < 0.05) was found after 6 weeks of detraining compared to POST-1 in the EI at 50% of the PT  and in the EI at 75% of the PT  in both experimental groups. In the same way, EG6s showed an increase (p < 0.05) in POST-2 from PRE evaluation in the EI at 50% of the PT (Significant increases (f the PT .The main purpose of this study was to compare the effects of the execution time of eccentric contraction (3 s vs. 6 s) on the morphological and elastic properties of the PT after a 6 week SLDSe training program. Although changes in the thickness of the PT were evidenced in both experimental groups after the completion of the SLDSe program, it is worth noting an increase of ~7% at the level of the lower pole of the patella in EG3s, and an increase of ~10% at the level of the anterior tuberosity of the tibia in EG6s. This is an important finding to be taken into account by physical therapists and sports adapters in the recovery of patellar tendinopathy, since depending on the level of the injury in the PT , one execution time of the eccentric contraction or the other should be used in the SLDSe exercise.Although the tendon is considered a poorly vascularized structure , it has Previous studies in animal models have shown that eccentric exercise modifies tendon gene expression producing an increase in collagen synthesis ,38. In tThe results obtained in tendon thickness agree with previous investigations that have analyzed the thicknesses of healthy and pathological tendons ,40. On tNo research has been found in the literature that has evaluated the residual effects on the morphological properties of the PT after the cessation of a training program using eccentric contractions. In the present investigation, it was observed that after hypertrophy in the tendon at the end of the intervention, the tendons of both experimental groups returned to their previous values recorded at the beginning of the study six weeks after cessation of activity. This situation may be due to the fact that, in addition to an increase in the synthesis of the collagen process, there is an increase in the concentrations of internal water and additional material that are more easily lost after the cessation of activity .In 2001, an increase in PT stiffness was reported for the first time after twelve weeks of training using isometric contractions . MoreoveOn the other hand, transient reductions in the hydration of Achilles  and PTs The PT is considered to be a short and thick tendon whose main function is to transmit the forces generated in the quadriceps to the tibia. In addition, the PT has other important functions, such as energy storage/release in the articular loading and unloading phases and protection against muscle injuries . TherefoIn conclusion, 6 weeks of SLDSe produced significant changes in the morphological properties of the PT. These adaptations were lost after 6 weeks of detraining. It was observed that longer times of execution of the eccentric contraction were associated with increases in the thickness of the PT at the distal level, and shorter times with increases at the proximal level. On the other hand, longer times of execution of the eccentric contraction induced a reduction in the tendon EI, and that regardless of the time of execution of the eccentric contraction, after 6 weeks of detraining there was an increase in the stiffness of the PT.