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Abstract
The aim of our research was to study the water and ethanol extractable polyphenols of stinging nettle (Urtica dioica L.) harvested in different seasons and to determine their antimicrobial activity against certain human pathogenic and food spoiling bacteria and yeasts.
Our results indicate that the spring leaf extracts had higher polyphenol contents than the root one; however, close to the end of the vegetation period these values decreased considerably in both leaves and roots. Detection and quantification of the most abundant phenolic compounds in the spring extracts by HPLC revealed the occurrence of 12 different phenol carboxylic acids and flavonoids. Flavonoid compounds were more abundant than phenol carboxylic acids in the leaves; however, their proportion was equal in the case of the roots. Nettle leaf extracts had remarkable antimicrobial activity, the spring extracts were more efficient than the autumn ones. Escherichia coli and Staphylococcus aureus were sensitive to every leaf extract, while Listeria monocytogenes and Pseudomonas aeruginosa had reduced but remarkable sensitivity patterns. Among the yeasts, Candida glabrata was strongly inhibited by the aqueous leaf extracts. Most of the strains were insensitive to the root extracts, although Enterococcus faecalis was inhibited by the root and not the leaf extracts.
Abstract
The present study aims to determine the effects of blending cementitious materials on the mechanical and durability properties of high-performance concrete (HPC). Densified silica fume and fine-grounded metakaolin are used as supplementary cementitious materials (SCMs). A total of 16 mixes containing both binary and ternary blending of SCMs were chosen for w/b ratios of 0.4 and 0.3 respectively. The hardened properties tested for the HPC mixes were compressive strength at 7, 28, and 90 days, flexural strength at 28 days, and modulus of elasticity at 28 days. Maximum strength gains up to 15%, 38%, and 23% for compression, flexure, and elastic modulus were observed in ternary mixes compared to binary mixes. Stress-strain behaviour of ternary mixes indicates increased tolerance of stress for the least amount of strain in the specimens. Based on the experimental results, empirical relations were developed and checked with the existing codes and by earlier researchers. The durability properties tested for HPC were water absorption at 28 days, acid attack, and sulphate attack at 28, 56, and 90 days. Ternary mixes improved the pore structure of HPC, resulting in a 56% reduction in water absorption and a 34% reduction in compressive strength loss due to immersion in 5% H2SO4 at 90 days. The findings of the study endorse that ternary blending of SF and MK can improve the engineering properties of HPC, and a mix containing SF 10% and MK 10% is recommended for the best results.
Abstract
Background and aims
The prominent cognitive-behavioral model of hoarding posits that information processing deficits contribute to hoarding disorder. Although individuals with hoarding symptoms consistently self-report attentional and impulsivity difficulties, neuropsychological tests have inconsistently identified impairments. These mixed findings may be the result of using different neuropsychological tests, tests with poor psychometric properties, and/or testing individuals in a context that drastically differs from their own homes.
Methods
One hundred twenty-three participants (hoarding = 63; control = 60) completed neuropsychological tests of sustained attention, focused attention, and response inhibition in cluttered and tidy environments in a counterbalanced order.
Results
Hoarding participants demonstrated poorer sustained attention and response inhibition than the control group (CPT-3 Omission and VST scores) and poorer response inhibition in the cluttered environment than when in the tidy environment (VST scores). CPT-3 Detectability and Commission scores also indicated that hoarding participants had greater difficulty sustaining attention and inhibiting responses than the control group; however, these effect sizes were just below the lowest practically meaningful magnitude. Posthoc exploratory analyses demonstrated that fewer than one-third of hoarding participants demonstrated sustained attention and response inhibition difficulties and that these participants reported greater hoarding severity and greater distress in the cluttered room.
Discussion and conclusions
Given these findings and other studies showing that attentional difficulties may be a transdiagnostic factor for psychopathology, future studies will want to explore whether greater sustained attention and response inhibition difficulties in real life contexts contribute to comorbidity and functional impairment in hoarding disorder.
Abstract
The present study aims to identify the most productive countries, journals, authors, institutions and the most used keywords in the field of special education during 2011–2020, based on the WoS database. The widespread effects of the papers and how they are related were analyzed with the bibliometric analysis method. The findings of the study showed that the USA is inarguably the most productive country, followed by England and Australia. On the other hand, there was a very strong positive correlation(r = 0.929) between the number of papers published by countries and their h-index, a similar finding was also found to be present between the countries' h-index and GDP per capita (r = 0.790). Moreover, it was found that the journals with the highest quartile (Q1 and Q2) in the field of special education published significantly more papers than the journals with the lowest quartile (Q3 and Q4). Matson, JL (USA), Sigafoos, J (New Zealand) and Lancioni, GE (Italy) were determined as the most prolific authors, respectively. Autism, intellectual disability, and Down syndrome were the phrases most frequently used as keywords. Our findings provide key information regarding the developments that the research direction of special education field has recently taken. This study also serves a potential roadmap for future studies.
Abstract
We tested several sample pre-treatment protocols for the study of oxygen isotope ratios in the phosphate phase of mammalian enamel of ten different fossil samples. We investigated the effect of different pre-treatment methods and the duration of the hydrogen fluoride treatment on enamel samples from skeletal phosphate with known δ18O values. The samples had been measured previously, so we could compare the ratios measured in our laboratory with the previous values to choose the best chemical preparation procedure. Four pre-soaking methods and two different time intervals of 2 mol dm−3 hydrogen fluoride treatment were compared during our experiments. In our experimental conditions, the distilled water wash and the 6 h of soaking in hydrogen fluoride gave the closest results to the expected δ-values. The steps of the tested preparation processes were repeated at least three times on each sample, so the reproducibility of the process could be also investigated.
Abstract
In in vivo infection trials, rainbow trout eyed eggs were exposed to three Saprolegnia parasitica (Oomycota) isolates, which differed in biological and genetic characteristics. Infection prevalence, hatching rate, hatching dynamics of fish eggs were quantified, and the study was complemented with histopathology and phylogenetic analyses. We experimentally detected intraspecific differences in the pathogenicity of S. parasitica on rainbow trout eggs. The isolate from rainbow trout eggs was the most virulent to eggs of the same host, whereas isolates from carp skin and fry did not cause as much damage to the eggs. Comparing the outcome of two experimental settings, we confirmed that invasion of fish eggs is more effective by hyphae growth than by the actively moving zoospores. In addition, our findings highlighted that S. parasitica isolates with 100% identical ITS DNA sequences, could differ significantly in virulence. These isolates can be clearly distinguished based on a 650-bp DNA fragment of the DNA-directed RNA polymerase II subunit (RPB2) gene.
Abstract
The introduction of school meals in the 20th century has its roots in several parallel but independent initiatives. The common source of these initiatives was the practice of philanthropy and charity, based on religious upbringing. Public catering for children was first institutionalized in Budapest by a charitable organization, the Children's Society (Gyermekbarátok Egyesülete), after which several denominational associations followed suit. In the early 20th century, the City of Budapest itself also took the initiative, setting up its first daycare centers where needy children were not only fed but also participated in educational and recreational activities. Resources for social welfare were eroded during the war, thus foreign aid organizations stepped in to help the children of Budapest immediately after the war, while childcare became the sole responsibility of the public authorities from the 1920s. From then on, the state covered the entire costs of providing meals, similar to the system of soup kitchens established specifically for supplying food to destitute adults.
Abstract
The Hungarian writer Sándor Petőfi (1823–1849) achieved the union of the Hungarian people thanks to the verses of his National Song (Nemzeti dal), which have always been quoted and recited with great interest. Therefore, the following paper aims to analyse some problems with the poem's translation into Spanish and present a new version of this emblematic poem for the Hungarians.
Abstract
Background
Mansonellosis is a widely neglected helminth disease which is predominantly observed in tropical regions. This study was conducted to assess potential associations of the prevalence of circulating Mansonella perstans-specific cell-free DNA in human serum and HIV infection in Ghanaian individuals.
Methods
For this purpose, serum samples obtained from Ghanaian HIV-patients (n = 989) and non-HIV-infected Ghanaian control individuals (n = 91) were subjected to real-time PCR targeting the ITS-(internal transcribed spacer-)2 sequence of M. perstans and Mansonella sp. Deux.
Results
Mansonella-specific cell-free DNA was detected in serum samples of only 2 HIV-positive and 0 HIV-negative individuals, making any reliable conclusions on potential associations between HIV and mansonellosis in tropical Ghana unfeasible.
Conclusions
Future epidemiological studies on hypothetical associations between mansonellosis and HIV infections should focus more specifically on high-endemicity settings for both Mansonella spp.-infections and HIV-infections, include higher case numbers and be based on real-time PCR from whole blood rather than from serum, in which only circulating parasite DNA but no more cell-bound parasite DNA can be detected. However, the study did not show associations of HIV infections in Ghanaian individuals with Mansonella worm loads high enough to detect cell-free Mansonella DNA in serum by PCR.
Grätzer and Lakser asked in the 1971 Transactions of the American Mathematical Society if the pseudocomplemented distributive lattices in the amalgamation class of the subvariety generated by 2 n ⊕ 1 can be characterized by the property of not having a * homomorphism onto 2 i ⊕ 1 for 1 < i < n.
In this article, this question is answered.
