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1.
Environ Toxicol Pharmacol ; 107: 104425, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38552756

RESUMO

The goal of the study was to analyse the concentrations of chemical elements (Fe, Ni, As, Cd, Pb, Hg, Cr, Zn) which are important for the determination of environmental toxins (e.g. resulting from smoking, exposure to harmful agents at work) in Polish patients with prostate cancer. The study covered 66 patients with diagnosed prostate cancer and 64 healthy volunteers over 50 years old. The analysis of the concentrations of selected chemical elements in whole blood was performed using inductively coupled plasma mass spectrometry (ICP-MS). In their blood, the patients with cancer had a significantly higher concentration of only one of the examined elements: arsenic. Additionally, the study group had lower concentrations of chromium, zinc, but also cadmium and lead, which are commonly regarded as carcinogenic. Taking into consideration the control group of healthy subjects of this study, we can assume that the subjects with prostate cancer were exposed to higher levels of arsenic, and that exposure to this element may be associated with an increased risk of cancer.


Assuntos
Arsênio , Neoplasias da Próstata , Oligoelementos , Masculino , Humanos , Pessoa de Meia-Idade , Oligoelementos/análise , Arsênio/análise , Polônia , Zinco/análise , Cádmio/análise , Neoplasias da Próstata/epidemiologia
2.
Ginekol Pol ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334352

RESUMO

The aim of the study was to analyze the activity of antioxidant enzymes (glutathione reductase, catalase, superoxide dismutase) and malondialdehyde (MDA) levels in a population of men with abnormal semen parameters and in a population of men diagnosed with normozoospermia. This study was performed using data collected at the Infertility Treatment Clinic 'Genesis' , Bydgoszcz, Poland, between 1 January 2011 and 31 December 2017. A total number of 321 men meeting the inclusion criteria were selected and divided into the control group (162 men) and the infertility group (159 men). The activities of superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR) were measured using ready-made kits; lipid peroxidation intensity was determined by the thiobarbituric acid method. No statistically significant differences were found for the activity of SOD, GR, CAT between the groups. MDA values measured in the serum of patients in the healthy group were higher than in the group with semenological disorders. Although our study did not demonstrate the usefulness of the above blood tests, further studies are needed to explore the potential use of assessing redox parameters to develop new diagnostic and therapeutic approaches for male infertility.

3.
Environ Sci Pollut Res Int ; 31(13): 19927-19945, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38367111

RESUMO

Environmental studies in Northern Poland are example of the functioning of ecophysiological relationships under anthropogenic impact. The aim of our studies was to investigate sex-dependent effects on the alterations in the concentration of chemical elements in soil samples collected from habitats of feral pigeon Columba livia f. urbana from Northern Poland, as well as feathers, biomarkers of oxidative stress, antioxidant defense, and total cholinesterase activity in tissues (liver, kidney, brain). Concentration of Si, Zn, and Pb in feathers of pigeons was significant. The levels of Si and Zn were higher in feathers of females from non-polluted, while higher Pb levels were found only in females from polluted areas (p = 0.000). This was confirmed by MANOVA of biomarkers of antioxidant defense, elements concentration, and revealing the order of effects: tissue type > environment > sex. Erythrocytes of males living in polluted areas were more fragile to hemolytic agents resulting in a higher percentage of hemolyzed erythrocytes. The effects of polluted environment on the level of carbonyl derivatives of oxidatively modified proteins compared to the effects of sex were more pronounced in the case of kidney (p = 0.000) and hepatic tissues (p = 0.000). Polluted areas were associated with significant increase in SOD activity in the brain and hepatic tissues of pigeons (p = 0.000). Health status of feral pigeons is significantly different in conditions of environmental destabilization.


Assuntos
Columbidae , Poluentes Ambientais , Animais , Feminino , Masculino , Columbidae/metabolismo , Antioxidantes/metabolismo , Chumbo/metabolismo , Poluentes Ambientais/análise , Estresse Oxidativo , Nível de Saúde , Biomarcadores/metabolismo , Colinesterases/metabolismo
4.
Healthcare (Basel) ; 11(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37685470

RESUMO

The COVID-19 pandemic demanded changes in healthcare systems worldwide. The lockdown brought about difficulties in healthcare access. However, trauma still required further attention considering its modifications. The presented study aims to investigate the variances in epidemiological patterns of trauma during the lockdown and the previous year, with a view to better understand the modifications in healthcare provision. The authors analyzed data from the first lockdown in 2020 (12 March-30 May) and the same period in 2019 from 35 hospitals in Lublin Province. A total of 10,806 patients in 2019 and 5212 patients in 2020 were included in the research. The uncovered changes adhered to the total admissions and mortality rate, the frequency of injuries in particular body regions, and injury mechanisms. The lockdown period resulted in a reduction in trauma, requiring an altered approach to healthcare provision. Our research indicates that the altered approach facilitated during such periods is essential for delivering tailored help to trauma patients.

5.
Ann Agric Environ Med ; 30(2): 281-286, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37387378

RESUMO

INTRODUCTION AND OBJECTIVE: Head and neck injuries are a heterogeneous group in terms of both clinical course and prognosis. For years, there have been attempts to create an ideal tool to predict the outcomes and severity of injuries. The aim of this study was evaluation of the use of selected artificial intelligence methods for outcome predictions of head and neck injuries. MATERIAL AND METHODS: 6,824 consecutive cases of patients who sustained head and neck injuries, treated in hospitals in the Lublin Province between 2006-2018, whose data was provided by National Institute of Public Health / National Institute of Hygiene, were analyzed retrospectively. Patients were qualified using International Statistical Classification of Diseases and Related Health Problems (10th Revision). The multilayer perceptron (MLP) structure was utilized in numerical studies. Neural network training was achieved with the Broyden-Fletcher-Goldfarb-Shanno (BFGS) method. RESULTS: In the designed network, the highest classification efficiency was obtained for the group of deaths (80.7%). The average value of correct classifications for all analyzed cases was 66%. The most important variable influencing the prognosis of an injured patient was diagnosis (weight 1.929). Gender and age were variables of less significance with weight 1.08 and 1.073, respectively. CONCLUSIONS: Designing a neural network was hindered due to the large amount of cases and linking of a large number of deaths with specific diagnosis (S06). With a predictive value of 80.7% for mortality, ANN can be a promising tool in the future; however, additional variables should be introduced into the algorithm to increase the predictive value of the network. Further studies, including other types of injuries and additional variables, are needed to introduce this method into clinical use.


Assuntos
Inteligência Artificial , Lesões do Pescoço , Humanos , Polônia/epidemiologia , Classificação Internacional de Doenças , Estudos Retrospectivos , Redes Neurais de Computação
6.
Foods ; 12(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38231696

RESUMO

The drying process is used in the food industry to extend the shelf life of fruits and vegetables without the use of preservatives. As quality, visual, and aroma characteristics are important determinants of consumer interest, they play a key role in the development of new foods. In the present study, vacuum impregnation (VI) was used prior to vacuum drying (VD) and freeze drying (FD) of courgette and broccoli. Organic beet juice was used to produce the novel snacks. The study showed that the use of vacuum impregnation significantly affected the VOCs profile (volatile organic compounds profile), in which the following compounds were found: viz: 2-(E)-hexen-1-ol, 2-(Z)-hexen-1-ol and aceto-phenone. VI caused a decrease in volumetric gel index (VGI), drying shrinkage (S), water activity (AW), decreased color saturation (∆C), and increased dry matter content (DM). All these properties testify to the positive effect of the pretreatment used. The drying methods used had a significant effect on the properties of the dried vegetables. The dries obtained by the FD method showed higher density and water activity, as well as better preserved color (lower ∆E) and higher VOCs, so it is considered that freeze drying is a suitable method for obtaining novel courgette and broccoli snacks.

7.
Environ Res ; 214(Pt 3): 114014, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35948152

RESUMO

Based on studies of the wintering population of mute swans in large urban agglomerations, it is possible to identify and infer the impact of environmental pollution in coastal regions near Baltic Sea on the physiological and biochemical changes in the blood of waterfowls. Hematological and biochemical changes in the blood in relation to chemical elements in their feathers are a useful tool for general ecophysiological conclusions. Hematological changes and blood chemistry in Mute Swan Cygnus olor is particularly environmentally dependent, therefore we examined hematological picture (red blood cells RBC, white blood cells WBC, heterophiles, eosinophils, basophils, monocytes, lymphocytes, hemoglobin, heterophile to lymphocyte ratio H/L, biochemical indicators (glucose, uric acid, total cholesterol, triglycerides, calcium, inorganic phosphorus, magnesium, total protein), stability of erythrocyte membranes, concentration of Ca, P, Mg in the blood, concentration of Al, Zn, Rh, Cu, Ru, Fe, Pb in feathers, in wintering population of 172 mute swans of different age (juvenile, adult) and gender, in three coastal types of areas of Southern Polish zone of Baltic Sea (Slupsk, Gdynia, Sopot). Percentage of changes in the morphological indices in the blood of mute swans with three independent characteristics (environment, sex, age) revealed that hemoglobin content exhibited the highest value (R2 = 53.8%) in the analysis of morphological indices; the effect of RBC, WBC, and basophils was much lower (WBC > RBC > basophils). Male and female erythrocytes from the coastal of Gdynia were more fragile than those of birds from coasts of Sopot and Slupsk. We found that osmotic fragility is altered in juvenile swans from Slupsk area and males from Gdynia area. The consequence was a higher level of hemolyzed erythrocytes in their blood. The effect of type of environment, age-, and sex-related impact on hematological indices and biomarkers of biochemical alterations in the blood of swans and comparison of these data with bioaccumulation of chemical elements in feathers of swans inhabiting 3 types of environment of Baltic coastal zone show significant differences in the hematological and biochemical indices. Albumins and globulins maintain the blood cations balance, however, changes in their concentrations in the blood suggest an impact on physiological mechanisms and body condition of swans.


Assuntos
Anseriformes , Animais , Anticorpos Antivirais , Aves , Poluição Ambiental , Feminino , Masculino , Estações do Ano
8.
Antioxidants (Basel) ; 11(5)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35624681

RESUMO

The intensification of oxidative stress and destabilization of the antioxidative defenses of an organism is a consequence of many environmental factors. We considered aspects conditioning male reproductive potential and the functionality of enzymatic antioxidative mechanisms, i.e., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR), and their correlations with Li, Be, B, Na, Mg, Al, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Ag, Cd, Sn, Sb, Ba, Hg, Tl, Pb, and malondialdehyde (MDA), as well as genetic polymorphism IL-4v.C589T (rs2243250) in men with infertility (n = 76). A healthy normozoospermic control (n = 87) was also used. We assessed the impact of negative changes driven by oxidative stress on enzymatic antioxidative mechanisms as well as the role of MDA in the overall process. On this basis, we infer connections between disturbances in enzymatic antioxidative defense and reproductive potential. Based on a molecular analysis of the polymorphism of gene IL-4v.C589T (rs2243250) (chromosome 5) (PCR-RFLP), we considered the relationships among particular genotypes with the possibility of occurrence of male infertility. Concentrations of chemical elements were measured in the blood. The activity of antioxidants and MDA levels were measured in serum. In the infertile group, higher GPx activity was noted (6.56 nmoL·min-1·mL-1, control: 4.31 nmoL·min-1·mL-1; p = 0.004), while GR achieved a greater level in the control (17.74 nmoL·min-1·mL-1, infertile: 15.97 nmoL·min-1·mL-1, p = 0.043), which implies diversified efficiency of the first and second lines of defense. The polymorphism of IL-4v.C589T (rs2243250) was not directly connected with infertility because there were not any differences in the frequency of genotypes between the infertile and control group (p = 0.578). An analysis of genotypes CC and TT (polymorphism IL-4v.C589T (rs2243250)) indicated numerous correlations between antioxidants, chemical elements and MDA. Therefore, chemical economy, antioxidative defense and genetic conditions are connected and jointly shape male reproductive potential. Chemical elements influence antioxidative defense and male fertility; the most important modulators appeared to be Na, Ba, Al and B. The polymorphism of gene IL-4v.C589T (rs2243250) has a limited influence on antioxidative defense and the metabolism of chemical elements.

9.
Molecules ; 27(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35268571

RESUMO

Lavandula angustifolia is one of the most widely cultivated non-food crops used in the production of essential oil; it is used in perfumery, aromatherapy, pharmaceutical preparations, and food ingredients. In this study, supercritical fluid extraction (SFE) and molecular distillation (MD) were combined, primarily to enrich scCO2 extracts with lavender oxygenated monoterpenes, avoiding thermal degradation, hydrolysis, and solvent contamination, and maintaining the natural characteristics of the obtained oils. Molecular distillation was developed for the first time for the extraction of crucial lavender fragrance ingredients, i.e., from two scCO2 extracts obtained from dry flower stems of lavender cultivated in Poland and Bulgaria. The best results for high-quality distillates were obtained at 85 °C (EVT) and confirmed that linalyl acetate content increased from 51.54 mg/g (initial Bulgarian lavender extract, L-Bg-E) and 89.53 mg/g (initial Polish lavender extract, L-Pl-E) to 118.41 and 185.42 mg/g, respectively, corresponding to increases of 2.3 and 2.1 times in both distillate streams, respectively. The distillates, light oils, and extracts from lavender were also evaluated for their antimicrobial properties by determining the minimum inhibitory concentration (MIC) by the broth microdilution method. Generally, Gram-positive bacteria and Candida spp. were more sensitive to all distilled fractions and extracts than Escherichia coli (Gram-negative bacteria).


Assuntos
Lavandula
10.
Nanomaterials (Basel) ; 12(3)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35159663

RESUMO

The synthesis of upconverting nanoparticles (NPs) is crucial for their spectroscopic properties and further applications. Reducing the size of materials to nano-dimensions usually decreases emission intensity. Therefore, scientists around the world are trying to improve the methods of obtaining NPs to approach levels of emission intensity similar to their bulk counterparts. In this article, the effects of stearic acid on the synthesis of core@shell ß-NaYF4: 18%Yb3+, 2%Er3+@ß-NaYF4 upconverting NPs were thoroughly investigated and presented. Using a mixture of stearic acid (SA) with oleic acid and 1-octadecene as components of the reaction medium leads to the obtaining of monodispersed NPs with enhanced emission intensity when irradiated with 975 nm laser wavelength, as compared with NPs prepared analogously but without SA. This article also reports how the addition of SA influences the structural properties of core@shell NPs and reaction time. The presence of SA in the reaction medium accelerates the growth of NPs in comparison with the analogic reaction but without SA. In addition, transmission electron microscopy studies reveal an additional effect of the presence of SA on the surface of NPs, which is to cause their self-organization due to steric effects.

11.
Environ Res ; 210: 112907, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35150715

RESUMO

An region of ecological hazard (EHR) is an area where, as a result of intensive human economic activity, degradation of components of the natural environment has taken place, leading to the deterioration of the ecological balance. EHR management is a globalised ever-increasing challenge. To eliminate the hazardous effect of these pollutants, research has been accelerated worldwide. The current study analyzed the specific biomarkers of the lipid and protein oxidation, total antioxidative status, activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione reductase and peroxidase), lysosomal enzymes (alanyl aminopeptidase, leucyl aminopeptidase, acid phosphatase), and biomarkers of aerobic and anaerobic metabolic pathways (activities of alanine and aspartate aminotransferases, succinate dehydrogenase, lactate dehydrogenase, lactate and pyruvate levels) in skeletal muscle tissue of wild great tit nestlings in environments with different levels of anthropogenic pressure such as sodium industry and agriculture in the central part of northern Poland (Inowroclaw EHR). Control samples were collected from Tuchola Forest and Borkowo village, where no direct sources of contamination were found. The relevance of the study was to assess the changes in lysosomal functioning caused by pollution-induced oxidative stress that may indicate multidirectional adaptative mechanisms of metabolic processes occurring in the wild birds to compensate for the negative effects of contamination. It was shown that the initiation of oxidative stress caused by anthropogenic pollution shifted the balance of the normal functioning of lysosomal enzymes towards their increased activity. A general tendency towards an increase in the intensity of lipid peroxidation processes with an increasing level of oxidatively modified proteins (aldehydic and ketonic derivatives) and a simultaneous reduction in the TAS was observed in the muscle tissue of great tits living in the anthropogenically modified areas. The intensity of lipid peroxidation and protein damage caused changes and reorganization of the energy-related metabolic pathways in the muscle tissue of wild great tits living in the sodium industry and agricultural areas of the EHR.


Assuntos
Passeriformes , Sódio , Agricultura , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Humanos , Peroxidação de Lipídeos , Lisossomos/metabolismo , Músculos/metabolismo , Estresse Oxidativo/fisiologia , Passeriformes/metabolismo , Polônia
12.
Environ Sci Pollut Res Int ; 29(3): 4632-4640, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34409535

RESUMO

The aim of the study was to analyze the activity of antioxidant enzymes (glutathione S-transferase, catalase, superoxide dismutase) and the concentration of malondialdehyde in order to determine the role of detoxification mechanisms in prostate cancer. The activities of superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) were measured using ready-made kits; lipid peroxidation intensity was determined by the thiobarbituric acid method. Superoxide dismutase was the only enzyme among antioxidant and detoxification enzymes for which a statistically significant difference in activity was found between the studied groups (1.4 U·ml-1 in patients vs. 1.6 U·ml-1 in control). No statistically significant differences were found for GST, CAT or the concentration of MDA between the group of men with prostate cancer and the control group. The lower SOD activity in men with prostate cancer may be due to a deficiency in their antioxidant defense system.


Assuntos
Estresse Oxidativo , Neoplasias da Próstata , Antioxidantes/metabolismo , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Humanos , Peroxidação de Lipídeos , Masculino , Malondialdeído , Polônia , Superóxido Dismutase/metabolismo
13.
J Colloid Interface Sci ; 606(Pt 2): 1421-1434, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492477

RESUMO

The right choice of synthesis route for upconverting nanoparticles (UCNPs) is crucial for obtaining a well-defined product with a specific application capability. Thus we decided to compare the physicochemical, cytotoxic, and temperature-sensing properties of UCNPs obtained from different rare earth (RE) ions, which has been made for the first time in a single study. The core/shell NaYF4:Yb3+,Er3+/NaYF4 UCNPs were obtained by reaction in a mixture of oleic acid and octadecene, and their highly stable water colloids were prepared using the ligand-free modification method. Both oleate-capped and ligand-free UCNPs exhibited a bright upconversion emission upon 975 nm excitation. Moreover, slope values, emission quantum yields, and luminescence lifetimes confirmed an effective energy transfer between the Yb3+ and Er3+ ions. Additionally, the water colloids of the UCNPs showed temperature-sensing properties with a good thermal sensitivity level, higher than 1 % K-1 at 358 K. Evaluation of the cytotoxicity profiles of the obtained products indicated that cell viability was decreased in a dose-dependent manner in the analyzed concentration range.


Assuntos
Nanopartículas , Ácido Oleico , Luminescência , Análise Espectral , Temperatura
14.
Sci Rep ; 11(1): 18846, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34552158

RESUMO

Water-dispersible up-converting nanoparticles (UCNPs) are known to be very effective in biomedical applications. Research groups have paid special attention to the synthesis of hydrophilic UCNPs with good physicochemical properties. Being aware of this, we decided to improve the ligand-free modification method of OA-capped NaYF4:Yb3+,Er3+/NaYF4 UCNPs prepared by precipitation in high-boiling-point solvents as the thus-far reported methods do not provide satisfactory results. Different molarities of hydrochloric acid and various mixing times were selected to remove the organic ligand from the NPs' surface and to discover the most promising modification approach. Highly water-stable colloids were obtained with a very high reaction yield of up to 96%. Moreover, the acid treatment did not affect the morphology and the size of the product. All of the crystals exhibited a bright up-conversion emission under 975-nm excitation, which confirmed the two-photon excitation and effective energy transfer between the used dopant ions. Thus, we could establish the most successful ligand-free modification procedure.

15.
Urol Case Rep ; 39: 101792, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34401346

RESUMO

Leiomyoma is a benign tumor originate from mesenchymal or connective tissue. Because of a low incidence, difficulties in differentiation from other renal tumors with imaging modalities, the definitive diagnosis of a leiomyoma is possible after examination of a specimen. We present a case of 79-years-old women with incidentally discovered renal tumor in CT scan. Because of the small size of a tumor, patient was informed about possibility of active surveillance. Partial nephrectomy was performed with a histopathologic diagnosis of renal leiomyoma. After 6 months of a follow-up, patient is found to be asymptomatic and free of disease.

16.
J Environ Health Sci Eng ; 19(1): 793-804, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34150274

RESUMO

Common carp (Cyprinus carpio) is one of the most important cultured fish species in Poland. The aims of our study were to determine the concentration of essential minerals in the muscle tissue of carp obtained from a pond culture and to compare the content of these minerals with the physiological norms of nutrition for the Polish population, Recommended Dietary Allowances (RDA), and Estimated Average Requirements (EAR). The non-carcinogenic and carcinogenic risk by assessment of the Estimated target hazard quotients (THQ), total target hazard quotients (ΣTHQ), and carcinogenic risk were also studied. The muscle tissue of the carp was rich in macroelements. The pattern significance gradation of element concentrations was as follows: Na > K > Ca > P > Mg > Al > Zn > Fe > Cu > Mn > Cr > Se > Co. The concentration of toxic heavy metals in the samples was lower than the maximum allowable level of metals in food products. The risk of consumption of toxicants by an adult at a daily intake of 100 g of fish was 1.45% for Pb, 0.1% for Hg, 0.02% for Cd, and 0.02% for As, compared to the allowable daily intake for each toxicant. The value of the target hazard quotients of each metal was less than 1, indicating that the intake of a single metal through the consumption of carp meat does not pose a considerable health hazard. The total value of the target hazard quotients was also less than 1, indicating the safety of the combined effects of the chemicals. The major risk contributor was Pb with 82.9%, followed by Hg (9.38%), As (6.43%), and Cd (1.29%).

17.
Nanoscale ; 13(15): 7322-7333, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33889899

RESUMO

Nanoparticles (NPs) based on host compound NaYF4 with core@shell structures were synthesised by the precipitation reaction in high-boiling point octadecene/oleic acid solvent. Four laser wavelengths were used (808, 975, 1208, or 1532 nm) for excitation of the obtained NPs. The resulting emission and mechanisms responsible for spectroscopic properties were studied in detail. Depending on NP compositions, i.e. type of doping ion (Er3+, Tm3+, or Yb3+) or presence of dopants in the same or different phases, adjustable up-conversion (UC) could be obtained with emission peaks covering the visible to near-infrared range (475 to 1625 nm). The presented results demonstrated multifunctionality of the prepared NPs. NaYF4:2%Tm3+@NaYF4 NPs exhibited emission at 700 and 1450 nm under 808 nm laser excitation or 800 and 1625 nm emission under 1208 nm laser radiation, as a result of ground- and excited-state absorption processes (GSA and ESA, respectively). However, NaYF4:5%Er3+,2%Tm3+@NaYF4 NPs showed the most interesting properties, as they can convert all studied laser wavelengths due to the absorption of Tm3+ (808, 1208 nm) or Er3+ ions (808, 975, 1532 nm), revealing a photon avalanche process under 1208 nm laser excitation, as well as GSA and ESA at other excitation wavelengths. The NaYF4:2%Tm3+@NaYF4:5%Er3+ NPs revealed the resultant emission properties, as the dopant ions were separated within core and shell phases. The NaYF4:18%Yb3+,2%Tm3+@NaYF4 and NaYF4:18%Yb3+,2%Tm3+@NaYF4:5%Er3+ samples showed the brightest emission, around 800 nm, under 975 nm excitation, though other laser wavelengths allowed for observation of luminescence, as well, especially in NPs with Er3+ in the outer shell, capable of UC under 1532 nm. The presented results highlight the unique and universal properties of lanthanide ions for designing luminescent NPs for a variety of potential applications, such as confocal microscopy.

18.
Sensors (Basel) ; 21(4)2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672985

RESUMO

This paper is an attempt to evaluate the effectiveness of the ship's hull air lubrication system in order to reduce the drag leading to fuel consumption reduction by ships. The available papers and reports were analyzed, in which records of the operation parameters of the propulsion system of ships equipped with this system were presented. These reports clearly show the advantages of using air lubrication system. On the basis of collected operating parameters of the propulsion system the authors performed analysis of operation effectiveness of the Air Lubrication System on the modern passenger ship was. The results of this analysis do not allow for a clearly positive opinion about its effectiveness. Additionally, the conditions that should be met for the system to be more effective and to significantly increase the propulsion efficiency were indicated.

19.
Proc Math Phys Eng Sci ; 476(2239): 20200056, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32821240

RESUMO

Cadmium telluride (CdTe) solar cells are deposited in current production using evaporation-based tech- niques. Fabricating CdTe solar cells using magnetron sputtering would have the advantage of being more cost-efficient. Here, we show that such deposition results in the incorporation of the magnetron working gas Ar, within the films. Post deposition processing with CdCl2 improves cell efficiency and during which stacking faults are removed. The Ar then accumulates into clusters leading to the creation of voids and blisters on the surface. Using molecular dynamics, the penetration threshold energies are determined for both Ar and Xe, with CdTe in both zinc-blende and wurtzite phases. These calculations show that more Ar than Xe can penetrate into the growing film with most penetration across the (111) surface. The mechanisms and energy barriers for interstitial Ar and Xe diffusion in zinc-blende are determined. Barriers are reduced near existing clusters, increasing the probability of capture-based cluster growth. Barriers in wurtzite are higher with non-Arrhenius behaviour observed. This provides an explanation for the increase in the size of voids observed after stacking fault removal. Blister exfoliation was also modelled, showing the formation of shallow craters with a raised rim.

20.
Int J Mol Sci ; 21(15)2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722328

RESUMO

We explain environmental and genetic factors determining male genetic conditions and infertility and evaluate the significance of environmental stressors in shaping defensive responses, which is used in the diagnosis and treatment of male infertility. This is done through the impact of external and internal stressors and their instability on sperm parameters and their contribution to immunogenetic disorders and hazardous DNA mutations. As chemical compounds and physical factors play an important role in the induction of immunogenetic disorders and affect the activity of enzymatic and non-enzymatic responses, causing oxidative stress, and leading to apoptosis, they downgrade semen quality. These factors are closely connected with male reproductive potential since genetic polymorphisms and mutations in chromosomes 7, X, and Y critically impact on spermatogenesis. Microdeletions in the Azoospermic Factor AZF region directly cause defective sperm production. Among mutations in chromosome 7, impairments in the cystic fibrosis transmembrane conductance regulator CFTR gene are destructive for fertility in cystic fibrosis, when spermatic ducts undergo complete obstruction. This problem was not previously analyzed in such a form. Alongside karyotype abnormalities AZF microdeletions are the reason of spermatogenic failure. Amongst AZF genes, the deleted in azoospermia DAZ gene family is reported as most frequently deleted AZF. Screening of AZF microdeletions is useful in explaining idiopathic cases of male infertility as well as in genetic consulting prior to assisted reproduction. Based on the current state of research we answer the following questions: (1) How do environmental stressors lessen the quality of sperm and reduce male fertility; (2) which chemical elements induce oxidative stress and immunogenetic changes in the male reproductive system; (3) how do polymorphisms correlate with changes in reproductive potential and pro-antioxidative mechanisms as markers of pathophysiological disturbances of the male reproductive condition; (4) how do environmental stressors of immunogenetic disorders accompany male infertility and responses; and (5) what is the distribution and prevalence of environmental and genetic risk factors.


Assuntos
Azoospermia , Exposição Ambiental/efeitos adversos , Estresse Oxidativo , Espermatogênese , Azoospermia/genética , Azoospermia/imunologia , Azoospermia/metabolismo , Azoospermia/patologia , Cromossomos Humanos/genética , Cromossomos Humanos/imunologia , Cromossomos Humanos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Humanos , Masculino , Estresse Oxidativo/genética , Estresse Oxidativo/imunologia , Polimorfismo Genético , Proteínas com Motivo de Reconhecimento de RNA/genética , Proteínas com Motivo de Reconhecimento de RNA/imunologia , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Espermatogênese/genética , Espermatogênese/imunologia
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