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71.
The article presents research on the potential use of organometallic compounds with the addition of antimony (III) oxide Sb2O3 as a coating additive that will make coatings susceptible to electroless metallization after prior surface irradiation with 193 nm wavelength laser radiation and a different number of laser pulses. The surface modification and activation effects were assessed by optical-imagining as well as by scanning electron microscopy (SEM) with energy dispersive analysis (EDX). It was found that the presence of Sb2O3 in the coating made it possible to reduce the content of the copper complex, causing an intensive surface ablation, resulting in the formation of a conical structure with a higher content of metallic copper nuclei.  相似文献   
72.
The process of platinum recovery from used car catalysts is highly desirable for both economic and environmental reasons. From the many available methods of processing used car catalysts, the article conducted both numerical and experimental studies using a device based on the collector metal method with lead as a modified medium through a magnetohydrodynamic pump for washing platinum from the channels of the ceramic catalyst carrier. It was assumed that lead alloys with the addition of lithium increase the extraction of platinum from thin catalytic layers and accelerate the platinum dissolution reaction in the Pb-Li alloy, which is the result of a greater affinity of lithium for platinum compared to lead. This assumption was verified by numerical simulations as well as laboratory tests. Tests were carried out for the secondary supply voltage range between 40 and 60 V and the catalyst flushing time between 240 and 480 s. Graphical results of the research were discussed.  相似文献   
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(1) Background: Dental caries is a chronic disease that affects a child’s dentition from the first stages of life. Several factors contribute to the development of the disease, including an improper diet. This cross-sectional study aimed to identify risk factors of dental caries in 12-year-old adolescents from Greater Poland and Lubusz Provinces (Poland). (2) Material and methods: The research was conducted in adolescents from five primary schools. A questionnaire consisted of close-ended questions on socioeconomic characteristics on family, diet, and oral hygiene habits. An assessment of the dentition was carried out in accordance with World Health Organization (WHO) recommendations. In addition to cavitated carious lesions, incipient caries lesions were noted according to the International Caries Detection and Assessment System, adapted for epidemiological studies (ICDASepiDMFt). (3) Results: The mean number of teeth with untreated caries; removed due to caries; and restored because of caries (DMFt) was 1.52 ± 1.90, while the ICDASepiDMFt index amounted to 2.64 ± 2.55, respectively. Children who did not brush every day had significantly higher odds of having ICDASepiDMFt > 0 than children brushing at least once daily (OR = 10.32, 95% CI = 1.36–78.32, p = 0.0240). Adolescents who drank sweet carbonated drinks every day had significantly higher ICDASepiDMTt than children who drank sweet carbonated drinks less frequently (p = 0.0477). (4) Conclusions: The research revealed that dental caries indices of 12-year-old adolescents from Greater Poland and Lubusz Provinces depend mainly on oral hygiene behaviors. The only significant nutritional factor that differentiated the caries intensity was the daily consumption of sweet carbonated drinks.  相似文献   
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The objective of the study was to assess the severity of depression and to assess the level of self-sufficiency of patients with Alzheimer's disease, with particular emphasis on the place of residence and level of education. The study covered 90 people diagnosed with Alzheimer's disease. All respondents were persons over 65?years of age and residents of cities with a population over one-hundred thousand. The research method based on this work is the author's own questionnaire, the Zung Self-Rating Depression Scale (ZSDS) about depression and the Karnofsky Performance Scale Index (KPSI) for assessment of a patient's self-sufficiency. Regardless of residence, patients with Alzheimer's disease displayed signs of mild or moderate depression (100% in social welfare homes and hospital patients and 60% in those with caregivers at home). Patients with Alzheimer's disease have an unsatisfactory salary in social-economic terms. In those with Alzheimer's disease, quality of life is best for those in family homes under the care of their immediate family. People with a vocational education were the largest group of people diagnosed with Alzheimer's. Patients at home and in the hospital had a higher level of physical activity, but most patients in the hospital needed regular medical care, as did patients in social welfare homes.  相似文献   
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The aim of this study was to determine the possibility of using feathers of blue tit nestlings to assess the level of endogenous accumulation of lead. For this purpose we conducted an experiment with lead application to randomly chosen nestlings from eight randomly drawn broods. Five days after the exposure, feathers of lead-treated nestlings had significantly higher lead concentrations than control nestlings. This result suggests that feathers can be used as reliable non-destructive bioindicators to assess the level of heavy metals originating from contaminated food, which is of great significance for comparative studies on ecological consequences of pollution.  相似文献   
80.
Antibiotic resistance of Staphylococcus-like organisms (STLO) isolated from a recreational sea beach located on the southern coast of the Baltic Sea was studied. The results of the present study showed that STLO inhabiting sand and seawater of the beach strongly differed in the resistance level to tested antibiotics. These microorganisms were most resistant to ampicillin, penicillin, oxytetracycline and susceptible to gentamicin, neomycin and streptomycin. Moreover, the level of antibiotic resistance among bacteria isolated from different parts of the beach also differed. Bacteria inhabiting the seawater, shoreline and the middle part of the beach were more antibiotic-resistant than bacteria isolated from the dune. The majority of bacteria inhabiting the seawater and sand were resistant to 3–8 antibiotics out of 12 tested in this study. Generally, there was no difference in antibiotic resistance between Staphylococcus-like organisms isolated from the surface and subsurface sand layers. STLO strains isolated from Ustka Beach were most resistant to β-lactam and tetracycline antibiotics, and most susceptible to aminoglycosides.  相似文献   
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