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1.
PeerJ ; 11: e15248, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283889

RESUMO

Macrophytes are one of the important indicators used in assessing the anthropic impact on aquatic ecosystems. The structure of macrophyte communities of two rivers were compared by species composition, dominant species and projective cover using statistical methods. It is shown that the influence of storm runoff on these rivers is manifested in the form of a change in the dominant species composition. Based on the statistical analysis carried out, it can be argued that, despite the peculiarities of the flora composition of each of the rivers, the influence of storm runoffs largely neutralizes this specificity, determining the situation in local areas immediately below the runoff. In the area of the effluent discharge the dominance of individual species and an increase in the area overgrown with macrophytes was observed. In the area of stormwater discharge on the Psel River, species were usually present: Nuphar lutea, Ceratophyllum demersum, Myriophyllum spicatum and on the Bystrica River-Glyceria maxima, Sagitaria sagittiformis, Stuckenia pectinata and Potamogeton crispus. The use of the NMDS method has been found to provide good insight into the structural rearrangements in macrophyte communities affected by runoff from stormwater systems.


Assuntos
Potamogetonaceae , Rios , Ecossistema , Biomarcadores Ambientais , Poaceae , Sementes
2.
Materials (Basel) ; 16(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37241332

RESUMO

The environment of an underground structure is much more complex than the above-ground environment. Erosion processes are underway in soil and groundwater; groundwater seepage and soil pressure are also typical for underground environments. Alternating layers of dry and wet soil have a strong effect on concrete, and they reduce its durability. Corrosion of cement concretes is caused by the diffusion of free calcium hydroxide, located in the pores of concrete, from the volume of the cement stone to its surface, bordering on an aggressive environment, and the further transition of the substance through the phase boundary solid (concrete)-soil-aggressive environment (liquid). Due to the fact that all minerals in cement stone exist only in saturated or close-to-saturated solutions of calcium hydroxide, a decrease in the content of which in the pores of concrete as a result of mass transfer processes causes a change in the phase and thermodynamic equilibrium in the body of concrete and leads to the decomposition of highly basic compounds of cement stone and, consequently, to the deterioration of the mechanical properties of concrete (reduction in strength, modulus of elasticity, etc.). A mathematical model of mass transfer in a two-layer plate imitating the "reinforced concrete structure-layer of the soil-coastal marine area" system is proposed as a system of nonstationary partial derivative differential equations of the parabolic type with Newmann's boundary conditions inside the building and at the interface between the soil and the marine environment and with conjugating boundary conditions at the interface between the concrete and the soil. When the boundary problem of mass conductivity in the "concrete-soil" system is solved, expressions are obtained to determine the dynamics of the concentration profiles of the target component (calcium ions) in the volumes of the concrete and soil. As a result, one can select the optimum composition of concrete, having high anticorrosion properties, to extend the durability of the concrete constructions of offshore marine structures.

3.
Int J Mol Sci ; 24(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36675207

RESUMO

A better understanding of the pathogenesis of preterm birth (PTB) will allow us to lower the PTB rate, reducing perinatal morbidity and mortality. This article presents the hypothesis that premature placenta apoptosis could be a potential cause of PTB. We evaluated gene expression involved in apoptosis: caspase-3, caspase-8, and XIAP (X-linked inhibitor of apoptosis) in the placenta during pregnancy (n = 41), at the onset of preterm labour (n = 42), after preterm (n = 44) and term (n = 32) labour. We used RNA extraction, reverse transcription, and PCR. During pregnancy the gene expression of caspase-3 and caspase-8 is low, but XIAP is higher than the caspases. At the onset of preterm labour, we observed a significantly increased expression of both caspase-8 (10.7-fold, p < 0.01) and caspase-3 (2.5-fold, p < 0.01) and XIAP (3-fold; p < 0.05) compared with expression during pregnancy. Our study showed that during pregnancy, the expression of caspase genes in the placenta is low and probably controlled by high XIAP expression. At the onset of preterm labour, the expression of caspase genes increases sharply. This may initiate the onset of preterm labour.


Assuntos
Caspase 3 , Caspase 8 , Trabalho de Parto Prematuro , Nascimento Prematuro , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X , Feminino , Humanos , Recém-Nascido , Gravidez , Caspase 3/genética , Caspase 3/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Expressão Gênica , Trabalho de Parto Prematuro/genética , Trabalho de Parto Prematuro/metabolismo , Placenta/metabolismo , Nascimento Prematuro/genética , Nascimento Prematuro/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
4.
PLoS One ; 17(10): e0275629, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36251723

RESUMO

A method for assessing the degree of impact of wastewater treatment plant discharge on receiving rivers was proposed, based on the structural indicators of the population of ciliated protozoa. It was shown that the ratio of attached, crawling and free-swimming forms in bottom sediments changes under the influence of discharge. In the points subject to organic pollution, the share of attached filter-feeding bacteriovorous ciliates increases in the assemblage of ciliated protozoa. The proposed Attached Form Index (AFI) takes this ratio into account. The use of AFI makes it possible to assess the restructuring of the assemblage of ciliated protozoa under the influence of point sources of pollution, to establish a zone of negative influence of runoff, to assess the degree of restoration of the aquatic ecosystem, as the influence of the pollution source weakened.


Assuntos
Cilióforos , Poluentes Químicos da Água , Purificação da Água , Ecossistema , Monitoramento Ambiental , Rios/química , Águas Residuárias
5.
PeerJ ; 8: e9325, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32596047

RESUMO

Reduction of the greenhouse effect is primarily associated with the reduction of greenhouse gas (GHG) emissions. Carbon dioxide (CO2) is one of the gases that increases the greenhouse effect - it is responsible for about half of the greenhouse effect. Significant sources of CO2 are wastewater treatment plants (WWTPs) and waste management, with about 3% contribution to global emissions. CO2 is produced mainly in the aerobic stage of wastewater purification and is a consequence of activated sludge activity. Although the roles of activated sludge components in the purification process have been studied quite well, their quantitative contribution to CO2 emissions is still unknown. The emission of CO2 caused by prokaryotes and eukaryotes over the course of a year (taking into account subsequent seasons) in model sequencing batch reactors (SBR) is presented in this study. In this work, for the first time, we aimed to quantify this contribution of eukaryotic organisms to total CO2 emissions during the WWTP process. It is of the order of several or more ppm. The contribution of CO2 produced by different components of activated sludge in WWTPs can improve estimation of the emissions of GHGs in this area of human activity.

6.
J Pregnancy ; 2019: 9795765, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30941219

RESUMO

INTRODUCTION: The aim of this study is to assess maternal cardiac function in the postpartum period, after 2 and 6 months in the parturient with preeclampsia and eclampsia. MATERIALS AND METHODS: Prospective study: 90 postpartum women after preeclampsia and eclampsia and 55 patients after an uncomplicated pregnancy. The parameters of maternal hemodynamics were recorded on days 1, 3, 5, 9, and 14 of postpartum period, after 2 and 6 months. The cardiac parameters were assessed. RESULTS: PE is accompanied by increased peripheral vascular resistance. The indicator of vascular resistance, SVR, is elevated for both mild and severe PE. With mild PE, a significant increase in SVR is observed up to 5 days of postpartum period, with severe PE/E up to 9 days. We found that in case of severe PE, SVR remains elevated to 6 months after delivery. The parameters of the contractile function of the heart (ESV, EDV, SV, SI, CO, СI, MVCF) were significantly decreased: with mild PE up to 5-9 days, with severe up to 9-14 days of puerperia. ESV, SV, SI, CO, and CI remain low with severe PE up to 6 months. The revealed decreasing of contractile function of the heart is a sign of asymptomatic heart failure. CONCLUSIONS: The hemodynamics of the puerperas after PE and E is characterized by impaired contractility of the myocardium and an increase in the indices of peripheral resistance. The degree of deviation in the parameters of cardiac hemodynamics and vascular resistance depended on the severity of hypertensive complications of pregnancy.


Assuntos
Eclampsia/fisiopatologia , Hemodinâmica , Contração Miocárdica , Parto/fisiologia , Período Pós-Parto/fisiologia , Pré-Eclâmpsia/fisiopatologia , Resistência Vascular , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Gravidez , Estudos Prospectivos , Índice de Gravidade de Doença , Fatores de Tempo
7.
J Environ Qual ; 46(4): 714-721, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28783801

RESUMO

This work presents the results of studies on the impact of spent drilling fluids cotreated with municipal wastewater on the rate of the wastewater treatment process and the structure of the community of eukaryotic organisms inhabiting an activated sludge. The studies were conducted under laboratory conditions in sequencing batch reactors. The effect of added polymer-potassium drilling fluid (DF1) and polymer drilling fluid (DF2) at dosages of 1 and 3% of wastewater volume on the rate of removal of total suspended solids, turbidity, chemical oxygen demand, and the content of total and ammonium nitrogen were analyzed, taking into account the values of these parameters measured at the end of each operating cycle. In addition to the impacts on the aforementioned physicochemical indices, the influence of drilling fluid on the biomass of various groups of eukaryotes in activated sludge was analyzed. The impact of the drilling fluid was highly dependent on its type and dosage. A noticeable slowdown in the rate of the wastewater treatment process and a negative effect on the organisms were observed after the addition of DF2. This effect intensified after an increase in fluid dose. However, no statistically significant negative changes were observed after the introduction of DF1. Conversely, the removal rate of some of the analyzed pollutant increased.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Nitrogênio
8.
J Environ Qual ; 46(1): 193-200, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28177406

RESUMO

Spent drilling muds are the liquid residues of rock drilling operations. Due to a high concentration of suspended solids and potentially detrimental chemical properties, they can negatively affect microorganisms participating in wastewater treatment processes. We evaluated the addition of a potassium-polymer drilling fluid (DF) to activated sludge in laboratory sequencing batch reactors (SBRs) for municipal wastewater treatment. Ciliate assemblage, the most dynamic component of eukaryotes in activated sludge, and which is highly sensitive to changes in the system, was evaluated. The average ciliate abundance dropped by about 51% (SBR 2; 1% DF added) and 33% (SBR 3; 3% DF added) in comparison to the control (SBR 1; wastewater only). A decrease in the total number of ciliate species during the experiment was observed, from 25 to 24 in SBR 2 and from 17 to 13 in SBR 3. Moreover, a drop in the number of dominant (>100 individuals mL) ciliate species was observed during the experiment-from eight in the control to five in SBR 2 and four in SBR 3-signaling noticeable changes in the quantitative structure of ciliate species. The species analyzed showed different responses to DF addition. The most sensitive was , which is bacteriovorus. In contrast, two predators, and , showed no reaction to DF addition. Our results indicate that addition of potassium-polymer DF, in doses of 1 to 3% of the treated wastewater volume, had no toxic effects on ciliates, but qualitative and quantitative changes in their community were observed.


Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos , Esgotos , Águas Residuárias
9.
Theriogenology ; 67(5): 1053-9, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17275901

RESUMO

Mammalian oocytes mature in follicular fluid (FF), surrounded by follicular cells. In the present study, in vitro maturation of bovine oocytes cultured in FF from dominant follicles 15-17mm in diameter (with various forms of heat pretreatment) and supplementation with follicular wall from follicles 3-5mm in diameter (FW1) were examined. Heat pretreatment of FF was as follows: (1) no treatment (FF1); (2) 56 degrees C for 30min (FF2); and (3) 100 degrees C for 20s (FF3). After IVM in FF1, oocytes underwent IVF and IVC and embryo development was assessed (up to the morula stage). The rate of oocyte maturation was decreased in pure FF1 versus control (44.5% versus 62.8%, P<0.001). In the control medium, FW1 did not significantly affect nuclear maturation. By contrast, the addition of FW1 to FF1 increased the rate of matured oocytes approximately two-fold (85.9% versus 45.6%, P<0.001). Furthermore, the maturation rate in the FF+FW1 system declined (from 85.9 to 71.0%, P<0.001), whereas that in the FF system increased (from 45.6 to 71.6%, P<0.001) with increased temperature of the FF treatment. Supplementation of the control medium with FW1 increased the yield of morulae (42.6% versus 13.7%, P<0.001). However, the stimulatory effect of FW1 on the morula rate was much higher in pure FF1 (72.5% versus 31.7%, P<0.001). These findings indicated, for the first time, the stimulatory impact of FW1 on in vitro maturation and early developmental capacity of bovine oocytes cultured in pure FF from dominant follicles. We also inferred that bovine FF constituents affecting bovine oocyte maturation and the meiosis-promoting ability of the FW were heat-labile.


Assuntos
Bovinos/fisiologia , Líquido Folicular/fisiologia , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Animais , Técnicas de Cultura de Células/métodos , Técnicas de Cultura de Células/veterinária , Meios de Cultura/farmacologia , Desenvolvimento Embrionário/fisiologia , Feminino , Fertilização in vitro/veterinária , Líquido Folicular/citologia , Masculino , Oócitos/citologia , Folículo Ovariano/citologia
10.
Theriogenology ; 66(2): 217-23, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16325901

RESUMO

In the hen ovary, each preovulatory follicle in the hierarchy, irrespective of its size and the level of its maturity is exposed to the preovulatory LH surge in each ovulatory cycle of an egg laying sequence. In the present study, the thecal weight and membrane protein content of theca layers at different stages of hen ovulatory cycle were assessed. Hens were killed 2 h (stage I), 9 h (stage II), 16 h (stage III), and 23 h (stage IV) after oviposition. The first (F1), second (F2), third (F3), fourth (F4) and fifth (F5) largest yellow follicles were utilized. In all follicles except F1, the thecal weight rose considerably between stages I and III (P < 0.05) followed by a slight cessation of the thecal growth at stage IV. The mean content of the theca membrane protein in F1-F5 follicles was lowest at stage III, increasing at stage IV (P < 0.05), although, in the case of individual follicles the difference was significant (P < 0.05) in F3 follicles only. Estradiol-17beta levels in the plasma were lowest (but not significant) at stage III, and a fourfold increase in the plasma progesterone concentration occurred at stage IV. These findings demonstrate for the first time the ovulatory cycle-related alterations in the thecal weight and membrane protein content in the hen preovulatory follicles. Data suggest that the preovulatory rise in ovarian steroid hormones is probably involved in transient termination of the growth and induction of differentiation of the theca in preovulatory follicles as they pass from one category to the next.


Assuntos
Galinhas/fisiologia , Células da Granulosa/metabolismo , Proteínas de Membrana/metabolismo , Folículo Ovariano/citologia , Ovulação/fisiologia , Células Tecais/metabolismo , Animais , Estradiol/sangue , Feminino , Folículo Ovariano/metabolismo , Folículo Ovariano/fisiologia , Progesterona/sangue , Células Tecais/ultraestrutura , Fatores de Tempo
11.
Biol Reprod ; 71(4): 1174-81, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15189831

RESUMO

The currently available evidence points to a possible influence of growth hormone (GH) on avian folliculogenesis, which can be mediated by both hepatic- and ovarian-derived IGF-I. Therefore, the purpose of the present study was to reveal GH-binding sites in granulosa and theca layers of preovulatory follicles and to determine the binding characteristics depending on the degree of follicular maturation and the stage of the ovulatory cycle in the hen. Hens were killed 2 h (stage I), 9 h (stage II), 16 h (stage III), and 23 h (stage IV) after oviposition, and the five largest yellow follicles (from F1 to F5) were removed. GH-binding sites in granulosa and theca layers from F1 to F5 follicles were characterized using a radioreceptor assay. Equilibrium dissociation constants (K(d)) and binding capacities (B(max)) were determined by Scatchard analysis of saturation curves, which revealed a single class of high-affinity GH-binding sites in both theca tissue and granulosa cells. In F1, F2, and F5 follicles, B(max) and K(d) for GH-binding sites in the granulosa layer changed during the ovulatory cycle, decreasing between stages I and III, to increase again at stage IV, with alterations in K(d) being less profound. No significant differences in binding capacities and affinities of GH-binding sites in the theca layer were found between various stages of the cycle. Furthermore, the concentration of GH-binding sites in the granulosa layer rose, whereas that in the theca layer fell with follicular enlargement. These findings indicate the presence of high-affinity GH-binding sites in both granulosa and theca layers of hen preovulatory follicles. Data also demonstrate that GH-binding sites in these tissues are regulated in a tissue-specific manner. Furthermore, the regulation of binding capacity of GH binding in granulosa cells by hormonal factors associated with ovulatory cycle is apparently not dependent on the state of follicular maturation.


Assuntos
Células da Granulosa/metabolismo , Hormônio do Crescimento/metabolismo , Folículo Ovariano/citologia , Reprodução/fisiologia , Células Tecais/metabolismo , Análise de Variância , Animais , Sítios de Ligação , Galinhas , Feminino , Tamanho do Órgão , Folículo Ovariano/metabolismo , Folículo Ovariano/fisiologia , Óvulo/metabolismo
12.
Rev. cuba. aliment. nutr ; 3(1): 90-4, ene.-abr. 1989. tab
Artigo em Espanhol | LILACS | ID: lil-85372

RESUMO

Se tomaron muestras de grasa en 3 plantas de rifinación. A las muestras se les hizo una mineralización sulfonitrica y se realizó la cuantificación de las concentraciones de hierro y de cobre por espectrofotometría de absorción atómica con llama aire-acetileno y lectura directa. Las medias de los valores están dentro de los límites máximos permisibles establecidos por el Codex Alimentarius


Assuntos
Cobre/análise , Espectrofotometria Atômica , Gorduras/análise , Ferro/análise
13.
Rev. cuba. aliment. nutr ; 3(1): 90-4, ene.-abr. 1989. tab
Artigo em Espanhol | CUMED | ID: cum-549

RESUMO

Se tomaron muestras de grasa en 3 plantas de rifinación. A las muestras se les hizo una mineralización sulfonitrica y se realizó la cuantificación de las concentraciones de hierro y de cobre por espectrofotometría de absorción atómica con llama aire-acetileno y lectura directa. Las medias de los valores están dentro de los límites máximos permisibles establecidos por el Codex Alimentarius


Assuntos
Ferro/análise , Cobre/análise , Gorduras/análise , Espectrofotometria Atômica
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