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1.
Stud Health Technol Inform ; 314: 42-46, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38785001

RESUMO

This study focuses on the complex interplay of healthcare, economic factors, and population dynamics, addressing a research gap in regional-level models that integrate diverse features within a temporal framework. Our primary objective is to develop an advanced temporal model for predicting cardiovascular mortality in Russian regions by integrating global and local healthcare features with economic and population dynamics. Utilizing a dataset from the Almazov Center's Department of Mortality Performance Monitoring, covering 94 regions and 752 records from January 1, 2015, to December 31, 2023, our analysis incorporates key parameters such as angioplasty procedures, population morbidity rates, Ischemic Heart Disease (IHD) and Cardiovascular Diseases (CVD) monitoring, and demographic data. Employing XGBoost and a regression model, our methodology ensures the model's robustness and generalizability.


Assuntos
Doenças Cardiovasculares , Previsões , Aprendizado de Máquina , Humanos , Doenças Cardiovasculares/mortalidade , Federação Russa/epidemiologia
2.
Sci Rep ; 13(1): 2020, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737633

RESUMO

For effective soil remediation, it is vital to apply environmentally friendly and cost-effective technologies following the notion of green sustainable development. In the context of recycling waste and preserving nutrients in the soil, biochar production and utilization have become widespread. There is an urgent need to develop high-efficiency biochar-based sorbents for pollution removal from soil. This research examined the efficacy of soil remediation using biochar made from three distinct sources: wood, and agricultural residues (sunflower and rice husks). The generated biochars were characterized by SEM/SCEM, XRF, XRD, FTIR, BET Specific Surface Area, and elemental compositions. The presence of hydroxyl and phenolic functional groups and esters in wood, sunflower and rice husk biochar were noted. The total volume of pores was in the following descending order: rice husk > wood > sunflower husk. However, wood biochar had more thermally stable, heterogeneous, irregular-shaped pores than other samples. Adsorption of soil-heavy metals into biochars differed depending on the type of adsorbent, according to data derived from distribution coefficients, sorption degree, Freundlich, and Langmuir adsorption models. The input of biochars to Calcaric Fluvic Arenosol increased its adsorption ability under contamination by Cu(II), Zn(II), and Pb(II) in the following order: wood > rice husk > sunflower husk. The addition of sunflower husk, wood, and rice husk biochar to the soil led to an increase in the removal efficiency of metals in all cases (more than 77%). The increase in the percentage adsorption of Cu and Pb was 9-19%, of Zn was 11-21%. The present results indicated that all biochars functioned well as an absorbent for removing heavy metals from soils. The tailor-made surface chemistry properties and the high sorption efficiency of the biochar from sunflower and rice husks could potentially be used for soil remediation.


Assuntos
Helianthus , Metais Pesados , Oryza , Poluentes do Solo , Solo/química , Chumbo , Metais Pesados/análise , Carvão Vegetal/química , Oryza/química , Adsorção , Poluentes do Solo/análise
3.
Environ Res ; 220: 115243, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36632881

RESUMO

The constant use of zinc oxide nanoparticles (ZnO NPs) in agriculture could increase their concentration in soil, and cause a threat to sustainable crop production. The present study was designed to determine the role of spore-forming and metal-tolerant bacteria, and biochar in alleviating the toxic effects of a high dose of ZnO NPs (2000 mg kg-1) spiked to the soil (Haplic Chernozem) on barley (Hordeum sativum L). The mobile compounds of Zn in soil and their accumulation in H. sativum tissues were increased significantly. The addition of biochar (2.5% of total soil) and bacteria (1010 CFU kg-1) separately and in combination showed a favorable impact on H. sativum growth in ZnO NPs polluted soil. The application of bacteria (separately) to the contaminated soil reduced the mobility of Zn compounds by 7%, due to loosely bound Zn compounds, whereas only biochar inputs lowered Zn mobile compounds mobility by 33%, even the combined application of biochar and bacteria also suppressed the soil Zn mobile compounds. Individual application of biochar and bacteria reduced the Zn plant uptake, i.e., underground parts (roots) by 44% and 20%, and in the above-ground parts of H. sativum plants by 39% and 13%, respectively, compared to ZnO NPs polluted soil treatments. Biochar, both separately and in combination with bacteria improved the root length by 48 and 85%, and plant height by 53 and 40%, respectively, compared to the polluted control. The root length and plant height decreased by 52 and 40% in ZnO NPs spiked soil compared clean soil treatments. Anatomical results showed an improvement in the structural organization of cellular-sub-cellular tissues of root and leaf. The changes in ultrastructural organization of assimilation tissue cells were noted all treatments due to the toxic effects of ZnO NPs compared with control treatment. The results indicate that metal-tolerant bacteria and biochar could be effective as a soil amendment to reduce metal toxicity, enhance crop growth, and improve soil health.


Assuntos
Hordeum , Nanopartículas Metálicas , Poluentes do Solo , Óxido de Zinco , Óxido de Zinco/toxicidade , Óxido de Zinco/química , Hordeum/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Metais/metabolismo , Bactérias/metabolismo , Solo/química , Poluentes do Solo/análise , Nanopartículas Metálicas/toxicidade
4.
Materials (Basel) ; 14(23)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34885332

RESUMO

In the presented study, LPBF 316L stainless steel tensile specimens were manufactured in three different orientations for the analysis of anisotropy. The first set of specimens was built vertically on the build platform, and two other sets were oriented horizontally perpendicular to each other. Tensile test results show that mean Young's modulus of vertically built specimens is significantly less then horizontal ones (158.7 GPa versus 198 GPa), as well as yield strength and elongation. A role of residual stress in a deviation of tensile loading diagrams is investigated as a possible explanation. Simulation of the build process on the basis of ABAQUS FEA software was used to predict residual stress in 316L cylindrical specimens. Virtual tensile test results show that residual stress affects the initial stage of the loading curve with a tendency to reduce apparent Young's modulus, measured according to standard mechanical test methods.

5.
Molecules ; 26(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34577019

RESUMO

1,3-Dipolar cycloaddition reactions of 2-substituted 5-R-3-nitropyridines and isomeric 3-R-5-nitropyridines with N-methyl azomethine ylide were studied. The effect of the substituent at positions 2 and 5 of the pyridine ring on the possibility of the [3+2]-cycloaddition process was revealed. A number of new derivatives of pyrroline and pyrrolidine condensed with a pyridine ring were synthesized.

6.
Environ Geochem Health ; 43(4): 1477-1489, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31989352

RESUMO

The paper presents the results of the model experiment on spring barley (Hordeum vulgare L.) grown in polluted soil. The influence of separate and combined application of wood biochar and heavy metal-tolerant bacteria on morpho-physiological, anatomical and ultrastructural parameters of H. vulgare L. has been studied. The joint application of biochar and bacteria increased the shoot length by 2.1-fold, root length by 1.7-fold, leaf length by 2.3-fold and dry weight by threefold compared to polluted variant, bringing the plant parameters to the control level. The maximal quantum yield of photosystem II decreased by 8.3% in H. vulgare L. grown in contaminated soil, whereas this decrease was less in biochar (7%), bacteria (6%) and in combined application of bacteria and biochar (5%). As for the transpiration rate, the H. vulgare L. grown in polluted soil has shown a decrease in transpiration rate by 26%. At the same time, the simultaneous application of biochar and bacteria has led to a significant improvement in the transpiration rate (14%). The H. vulgare L. also showed anatomical (integrity of epidermal, vascular bundles, parenchymal and chlorenchymal cells) and ultrastructural (chloroplasts, thylakoid system, plastoglobules, starch grains, mitochondria, peroxisomes, ribosomes, endoplasmic reticulum, vacuoles) changes, revealed by light-optical and transmission electron microscopy of leaf sections. The effects were most prominent in H. vulgare L., grown in polluted soil but gradually improved with application of biochar, bacteria and their combination. The use of biochar in combination with metal-tolerant bacteria is an efficient tool for remediation of soils, contaminated with heavy metals. The positive changes caused by the treatment can be consistently traced at all levels of plant organization.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Carvão Vegetal , Hordeum/fisiologia , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Adaptação Fisiológica , Folhas de Planta/fisiologia , Microbiologia do Solo , Madeira/química
7.
Environ Geochem Health ; 43(6): 2443-2454, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32737635

RESUMO

The effects of bulk- and nano-CuO were monitored on barley (Hordeum sativum L.) in hydroponic conditions. The anatomical and cyto-/morphometric parameters of plants, exposed to both types of CuO in different doses (300 and 2000 mg/L) were recorded. The germination rate, root and shoot lengths decreased in a dose-dependent manner. Exposure to nano-CuO significantly increased Cu content in the H. sativum roots; however, the translocation rates of dissolved Cu were low and showed less accumulation in above-ground tissues. The differences between nano- and bulk-CuO treated plants were sufficiently evident, but at lower concentrations, these differences were non-significant. The relative seed germination inhibition was noted up to 11% and 22% under the high dose of bulk- and nano-CuO, respectively; however, at low dose, it was non-significant. The relative root length was reduced 3.6 fold by bulk- and 1.5 fold by nano-CuO, and shoot lengths decreased 1.6 fold by bulk- and 1.4 fold by nano-CuO under the high dose after growth of 30 days. It indicated more morphological effects on H. sativum caused by bulk- than the nano-CuO. The cytomorphometric analysis indicated the average cortex cell, total cortex, and total central cylinder areas of root cells and the average areas of chlorenchyma leaf cells were increased as compared to control in both bulk- and nano-CuO treated plants. It showed destructive effects of nano- and bulk-CuO on cellular organizations of H. sativum anatomy. Thus, at the low dose, the minimal effects of nano-CuO were observed than the bulk. Therefore, the finding could be interest for the safe application of nano-CuO.


Assuntos
Cobre/farmacocinética , Hordeum/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Cobre/toxicidade , Germinação/efeitos dos fármacos , Hordeum/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Sementes/efeitos dos fármacos , Distribuição Tecidual
8.
Environ Geochem Health ; 43(6): 2407-2421, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33025349

RESUMO

The concentrations of ∑16 priority polycyclic aromatic hydrocarbons (PAHs) for soils, roots, and above-ground parts of reed (Phragmites australis Cav.) were determined on different monitoring plots located near the city of Kamensk-Shakhtinsky, southern Russia, where historically received industrial sewage and sludge. The total PAHs concentration in monitoring soil plots was significantly higher than those in the background site which situated at the distance of 2 km from the contamination source. Accordingly, the maximum accumulation was found for phenanthrene and chrysene among the 16 priority PAHs in most of the plant samples collected in the impact zone. The effects of PAHs' pollution on changes of Phragmites australis Cav. cellular and subcellular organelles in the studied monitoring sites were also determined using optical and electron microscopy, respectively. The obtained data showed that increasing of PAHs contamination negatively affected the ultrastructural changes of the studied plants. Phragmites australis Cav. showed a high level of adaptation to the effect of stressors by using tissue and cell levels. In general, the detected alterations under the PAHs effect were possibly connected to changes in biochemical and histochemical parameters as a response for reactive oxygen species and as a protective response against oxidative stress. The obtained results introduce innovative findings of cellular and subcellular changes in plants exposed to ∑16 priority PAHs as very persistent and toxic contaminants.


Assuntos
Organelas/efeitos dos fármacos , Poaceae/citologia , Poaceae/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/farmacocinética , Poluentes do Solo/farmacocinética , Monitoramento Ambiental , Organelas/química , Células Vegetais/efeitos dos fármacos , Células Vegetais/ultraestrutura , Componentes Aéreos da Planta/citologia , Componentes Aéreos da Planta/efeitos dos fármacos , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/ultraestrutura , Hidrocarbonetos Policíclicos Aromáticos/análise , Federação Russa , Esgotos , Poluentes do Solo/análise
9.
Stud Health Technol Inform ; 273: 262-265, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-33087624

RESUMO

The outbreak of COVID-19 has led to a crucial change in ordinary healthcare approaches. In comparison with emergencies re-allocation of resources for a long period of time is required and the peak utilization of the resources is also hard to predict. Furthermore, the epidemic models do not provide reliable information of the development of the pandemic's development, so it creates a high load on the healthcare systems with unforeseen duration. To predict morbidity of the novel COVID-19, we used records covering the time period from 01-03-2020 to 25-05-2020 and include sophisticated information of the morbidity in Russia. Total of 45238 patients were analyzed. The predictive model was developed as a combination of Holt and Holt-Winter models with Gradient boosting Regression. As we can see from the table 2, the models demonstrated a very good performance on the test data set. The forecast is quite reliable, however, due to the many uncertainties, only a real-world data can prove the correctness of the forecast.


Assuntos
Infecções por Coronavirus , Pandemias , Pneumonia Viral , Betacoronavirus , COVID-19 , Humanos , Morbidade , Federação Russa/epidemiologia , SARS-CoV-2
10.
Molecules ; 25(9)2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32397095

RESUMO

A number of novel 6-R-isoxazolo[4,3-b]pyridines were synthesized and their reactions with neutral C-nucleophiles (1,3-dicarbonyl compounds, π-excessive (het)arenes, dienes) were studied. The reaction rate was found to be dependent on the nature of the substituent 6-R. The most reactive 6-nitroisoxazolo[4,3-b]pyridines are able to add C-nucleophiles in the absence of a base under mild conditions. In addition, these compounds readily undergo [4+2]-cycloaddition reactions on aromatic bonds C=C(NO2) of the pyridine ring, thus indicating the superelectrophilic nature of 6-NO2-isoxazolo[4,3-b]pyridines.


Assuntos
Reação de Cicloadição , Piridinas/química , Piridinas/síntese química , Catálise
11.
Environ Geochem Health ; 42(1): 45-58, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30874936

RESUMO

Effects of Cu toxicity from contaminated soil were analysed in spring barley (Hordeum sativum distichum), a widely cultivated species in South Russia. In this study, H. sativum was planted outdoors in one of the most fertile soils-Haplic Chernozem spiked with high concentration of Cu and examined between the boot and head emergence phase of growth. Copper toxicity was observed to cause slow ontogenetic development of plants, changing their morphometric parameters (shape, size, colour). To the best of our knowledge, the ultrastructural changes in roots, stems and leaves of H. sativum induced by excess Cu were fully characterized for the first time using transmission electron microscopy. The plant roots were the most effected, showing degradation of the epidermis, reduced number of parenchyma cells, as well as a significant decrease in the diameter of the stele and a disruption and modification to its cell structure. The comparative analysis of the ultrastructure of control plants and plants exposed to the toxic effects of Cu has made it possible to reveal significant disruption of the integrity of the cell wall and cytoplasmic membranes in the root with deposition of electron-dense material. The changes in the ultrastructure of the main cytoplasmic organelles-endoplasmic reticulum, mitochondria, chloroplasts and peroxisomes-in the stem and leaves were found. The cellular Cu deposition, anatomical and ultrastructural modifications could mainly account for the primary impact points of metal toxicity. Therefore, this work extends the available knowledge of the mechanisms of the Cu effect tolerance of barley.


Assuntos
Cobre/toxicidade , Hordeum/efeitos dos fármacos , Poluentes do Solo/toxicidade , Parede Celular/efeitos dos fármacos , Parede Celular/ultraestrutura , Citoplasma/efeitos dos fármacos , Citoplasma/ultraestrutura , Hordeum/anatomia & histologia , Hordeum/citologia , Hordeum/ultraestrutura , Microscopia Eletrônica de Transmissão , Células Vegetais/efeitos dos fármacos , Folhas de Planta/citologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/ultraestrutura , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/ultraestrutura , Caules de Planta/citologia , Caules de Planta/efeitos dos fármacos , Caules de Planta/ultraestrutura , Federação Russa
12.
Rev Environ Contam Toxicol ; 252: 51-96, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31286265

RESUMO

In the past two decades, increased production and usage of metallic nanoparticles (NPs) have inevitably increased their discharge into the different compartments of the environment, which ultimately paved the way for their uptake and accumulation in various trophic levels of the food chain. Due to these issues, several questions have been raised on the usage of NPs in everyday life and have become a matter of public health concern. Among the metallic NPs, Cu-based NPs have gained popularity due to their cost-effectiveness and multifarious promising uses. Several studies in the past represented the phytotoxicity of Cu-based NPs on plants. However, comprehensive knowledge is still lacking. Additionally, the impact of Cu-based NPs on soil organisms such as agriculturally important microbes, fungi, mycorrhiza, nematode, and earthworms is poorly studied. This review article critically analyses the literature data to achieve a more comprehensive knowledge on the toxicological profile of Cu-based NPs and increase our understanding of the effects of Cu-based NPs on aquatic and terrestrial plants as well as on soil microbial communities. The underlying mechanism of biotransformation of Cu-based NPs and the process of their penetration into plants have also been discussed herein. Overall, this review could provide valuable information to design rules and regulations for the safe disposal of Cu-based NPs into a sustainable environment.


Assuntos
Cobre , Poluentes Ambientais , Nanopartículas Metálicas , Animais , Cadeia Alimentar , Oligoquetos , Solo
13.
Environ Geochem Health ; 42(1): 95-108, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31011941

RESUMO

Soils formed after the desiccation of Lake Atamanskoe, which has served as a reservoir for liquid industrial waste from the city of Kamensk-Shakhtinsky during a long time, were studied. These soils differ from zonal soils by a strong contamination with zinc and sulfur. Preliminary studies showed that Fe compounds fix a significant part of zinc. This requires to study S, Zn, and Fe minerals. In this work, Mössbauer spectroscopy was used for the identification of iron compounds and scanning electron microscopy was used for the microanalysis of these and other minerals. To facilitate the identification of Fe minerals, brown iron ocher was removed from a contaminated soil sample and analyzed. From electron microscopy and Mössbauer spectroscopy data, ocher contained hydrogoethite with a high content of sorption water and schwertmannite (a rare mineral, probably found in Russia for the first time). The chemical composition of this schwertmannite better corresponds to the Cashion-Murad model than to the Bigham model. Particles of partially oxidized magnetite and wustite enriched with zinc were revealed under electron microscope. Siderite with partial substitution of Fe2+ by Zn2+ was detected. Thus, contaminated hydromorphic soil contains both common minerals (illite, goethite, hematite, gypsum) and rare minerals (schwertmannite, Zn siderite, partially oxidized magnetite and wustite enriched with zinc).


Assuntos
Ferro/análise , Minerais/análise , Poluentes do Solo/análise , Enxofre/análise , Zinco/análise , Carbonatos/análise , Compostos Férricos/análise , Compostos Ferrosos/análise , Compostos de Ferro/análise , Minerais/química , Federação Russa , Solo/química
14.
Sci Total Environ ; 645: 1103-1113, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30248835

RESUMO

The rapid growth of copper oxide nanoparticles (CuO NPs) production and its abundant uses in many industries, and increasing release into an environment from both intentional and unintentional sources, create risks to spring barley (Hordeum sativum distichum), one of the most important staple food crop. Thereby, the aim of this study was to investigate the phytotoxicity of CuO NPs on H. sativum growth in hydroponic system. The CuO NPs inhibited H. sativum growth by affecting the germination rate, root and shoot lengths, maximal quantum yield of photosystem II, and transpiration rate. Structural and ultrastructural examination of H. sativum tissues using light, transmission and scanning electron microscopy showed effects on stomatal aperture and root morphology, metaxylem size and changes in cellular organelles (plastids, mitochondria), as well as in plastoglobules, starch granules, protoplasm, and membranes. The formation of electron-dense materials was noted in the intercellular space of cells of CuO NPs-treated plants. In addition, relative root length was one-third (35%) that of the control, and relative shoot length (10%) was also reduced. Further, the Cu content of roots and leaves of CuO NPs-treated plants was 5.7 and 6.4-folds higher than the control (without CuO NPs), respectively. Presented data were significant at p ≤ 0.05 compared to control. Conclusively, the results provide insights into our understanding of CuO NPs toxicity on H. sativum, and findings could be used for developing strategies for safe disposal of NPs.


Assuntos
Cobre/toxicidade , Hordeum/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Poluentes do Solo/toxicidade , Hordeum/fisiologia , Nanopartículas , Óxidos , Folhas de Planta
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