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Triethylammonium acetate ionic liquid assisted one-pot synthesis of dihydropyrimidinones and evaluation of their antioxidant and antibacterial activities
No full textAbstractA mild and efficient catalytic method has been developed to synthesize 3,4-dihydropyrimidinones in high yield by one-pot three component Biginelli condensation in the presence of triethylammonium acetate (TEAA) which acts as catalyst/reaction medium. Further, we have studied the antioxidant and antibacterial activities of these synthesized 3,4-dihydropyrimidinones. All the synthesized compounds reveal the significant antioxidant properties, these properties have been studied using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and cupric reducing antioxidant capacity (CUPRAC) assays. In addition, to this, these compounds also show the good antibacterial activity against four human pathogenic bacteria
Systemic inflammation, growth factors, and linear growth in the setting of infection and malnutrition
No full textAbstractObjectivesDeficits in weight gain and linear growth are seen frequently among children in areas where malnutrition and recurrent infections are common. Although both inflammation and malnutrition can result in growth hormone (GH) resistance, the interrelationships of infection, inflammation, and growth deficits in developing areas remain unclear. The aim of this study was to evaluate relationships between low levels of systemic inflammation, growth factors, and anthropometry in a case–control cohort of underweight and normal weight children in northern Brazil.MethodsWe evaluated data from 147 children ages 6 to 24 mo evaluated in the MAL-ED (Interactions of Malnutrition and Enteric Disease) case–control study following recruitment from a nutrition clinic for impoverished families in Fortaleza, Brazil. We used nonparametric tests and linear regression to evaluate relationships between current symptoms of infections (assessed by questionnaire), systemic inflammation (assessed by high-sensitivity C-reactive protein [hsCRP]), the GH insulin-like growth factor-1 (IGF-1) axis, and measures of anthropometry. All models were adjusted for age and sex.ResultsChildren with recent symptoms of diarrhea, cough, and fever (compared with those without symptoms) had higher hsCRP levels; those with recent diarrhea and fever also had lower IGF-1 and higher GH levels. Stool myeloperoxidase was positively associated with serum hsCRP. hsCRP was in turn positively associated with GH and negatively associated with IGF-1 and IGF-binding protein-3 (IGFBP-3), suggesting a state of GH resistance. After adjustment for hsCRP, IGF-1 and IGFBP-3 were positively and GH was negatively associated with Z scores for height and weight.ConclusionsInfection and inflammation were linked to evidence of GH resistance, whereas levels of GH, IGF-1, and IGFBP-3 were associated with growth indices independent of hsCRP. These data implicate complex interrelationships between infection, nutritional status, GH axis, and linear growth in children from a developing area
GC/MS profiling, in vitro antioxidant, antimicrobial and haemolytic activities of Smilax macrophylla leaves
No full textAbstractThe current study has been designed to appraise the antioxidant, antimicrobial and haemolytic potential of Smilax macrophylla leaves. The n-hexane fraction was analysed by Gas Chromatography/Mass Spectrometer which revealed the presence of 38 compounds. All examined extracts and fractions of plant leaves showed significant antimicrobial activity. The haemolytic effect of the plant was found to be in a range of 3.41–8.48%. S. macrophylla leaves contained substantial level of total phenolic contents (2.2–6.2 Gallic acid equivalent mg/g) and total flavonoid contents (1.2–4.5 Catechin, mg/g) of dry plant matter. Leaf extract and fractions also exhibited a good antioxidant potential when measured by DPPH radical scavenging assay (Inhibitory concentration 50%=33.4–72.3μg/mL). The antioxidant activity of plant extracts was also studied using sunflower oil as an oxidative substrate and found that it stabilized the oil. Significant (p<0.05) variations were observed in the results. The correlation between the results of different antioxidant assays and oxidation parameters of oil indicated that leaf extracts and fractions, exhibit considerable total phenolic contents, total flavonoid contents and scavenging power, along with more potent for enhancing the oxidative stability of sunflower oil. Considering these results, S. macrophylla could be used as a source for the exploration of new antimicrobial, antioxidant agents, functional food and nutraceutical applications
The oxygen isotopic composition of phosphate in river water and its potential sources in the Upper River Taw catchment, UK
No full textAbstractThe need to reduce both point and diffuse phosphorus pollution to aquatic ecosystems is widely recognised and in order to achieve this, identification of the different pollutant sources is essential. Recently, a stable isotope approach using oxygen isotopes within phosphate (δ18OPO4) has been used in phosphorus source tracing studies. This approach was applied in a one-off survey in September 2013 to the River Taw catchment in south-west England where elevated levels of phosphate have been reported. River water δ18OPO4 along the main channel varied little, ranging from +17.1 to +18.8‰. This was no >0.3‰ different to that of the isotopic equilibrium with water (Eδ18OPO4). The δ18OPO4 in the tributaries was more variable (+17.1 to +18.8‰), but only deviated from Eδ18OPO4 by between 0.4 and 0.9‰. Several potential phosphate sources within the catchment were sampled and most had a narrow range of δ18OPO4 values similar to that of river Eδ18OPO4. Discharge from two waste water treatment plants had different and distinct δ18OPO4 from one another ranging between +16.4 and +19.6‰ and similar values to that of a dairy factory final effluent (+16.5 to +17.8‰), mains tap water (+17.8 to +18.4‰), and that of the phosphate extracted from river channel bed sediment (+16.7 to +17.6‰). Inorganic fertilizers had a wide range of values (+13.3 to +25.9‰) while stored animal wastes were consistently lower (+12.0 to +15.0‰) than most other sources and Eδ18OPO4. The distinct signals from the waste water treatment plants were lost within the river over a short distance suggesting that rapid microbial cycling of phosphate was occurring, because microbial cycling shifts the isotopic signal towards Eδ18OPO4. This study has added to the global inventory of phosphate source δ18OPO4 values, but also demonstrated the limitations of this approach to identifying phosphate sources, especially at times when microbial cycling is high
Estimations from the exponentiated rayleigh distribution based on generalized Type-II hybrid censored data
No full textAbstractIn this article, unknown parameters of exponentiated Rayleigh distribution based on generalized Type II Hybrid censored data, survival function, failure rate function and coefficient of variation are derived by applying the maximum likelihood, Bayes and percentile bootstrap methods. Approximate confidence intervals for the unknown parameters, survival function, failure rate function and coefficient of variation are obtained. We study Bayes estimates under gamma priors distributions depending on symmetric and asymmetric loss functions via the Gibbs within Metropolis-Hasting samplers procedure. Finally, the proposed methods can be understood through illustrating the results of the real data analysis
High-capacity open bore membrane chromatography column based on micro-packed ceramic hollow fibres
No full textAbstractMicro-structured ceramic hollow fibres as a new (GC) column configuration has been designed, fabricated, and executed for the separation of gases. The design consists of ceramic hollow fibres with intensively self-arranged open micro-channels in its wall, which act as storage space, and the stationary phase is packed inside the micro-channels. The hollow lumen leads to negligible pressure drop along the GC column that is similar to the common capillary columns, whilst the intensively distributed micro-channels provide spacious volume for packing the stationary phase to realise much enhanced capacity that is close to common packed columns. Using alumina hollow fibre as an example, this novel design has been demonstrated as a GC column packed with 5Å molecular sieve particles and used to successfully separate nitrogen and oxygen. Such a GC column with a length of 8m was able to separate O2 and N2 completely, with an injection volume of 90μL, which is 20−30 times higher than a typical capillary column, and a negligible pressure drop of only 0.01bar. The theoretical plate number of this column for oxygen is up to almost 30 times higher than a commercial packed column's, and for nitrogen it is almost 10 times higher
Structural metamaterials with Saint-Venant edge effect reversal
No full textAbstractWhen a usual material is loaded statically at surfaces, fine fluctuations of surface strain diminish fast in the material volume with the distance to the surface, a phenomenon widely known as the Saint-Venant edge effect. In this paper, highly nonlocal discrete lattices are explored to demonstrate structural metamaterials featuring reversal of the Saint-Venant edge effect. In these materials, certain coarse patterns of surface strain may decay faster than the finer ones. This phenomenon is shown to arise from anomalous behavior of the Fourier modes of static deformation in the material, and creates opportunities for blockage, qualitative modification and in-situ recognition of surface load patterns. Potential applications and useful practical techniques of spectral analysis of deformation, density of states and phase diagram mapping are outlined
Daily rehabilitation improves physical function at 6 months, but not hospital length of stay, in patients with acute respiratory failure [synopsis]
No full textEruptive melanocytic nevi with malignant transformations and the connection to BRAF and p16 mutations
No full textAbstractEruptive melanocytic nevi (EMN) is a rare phenomenon with an unclear pathogenesis. Mutation on a molecular basis has been proposed, but insufficient data are available to confirm this hypothesis. Theoretically, the possibility of malignant transformation is high, but no previous definite cases had been reported. Herein, we report the first case of a patient with EMN in whom hypopharyngeal low-grade melanocytic malignancies were detected using a fibrolaryngoscope. BRAF activation and p16 mutations were discovered through real-time polymerase chain reaction and immunohistochemical staining on EMN tissue samples, respectively. The significance of these findings has yet to be determined
The use of predictive models to optimize risk of decisions
No full textAbstractThe purpose of this paper is to set up a mathematical framework that risk assessors and regulators could use to quantify the “riskiness” of a particular recommendation (choice/decision). The mathematical theory introduced here can be used for decision support systems. We point out that efficient use of predictive models in decision making for food microbiology needs to consider three major points: (1) the uncertainty and variability of the used information based on which the decision is to be made; (2) the validity of the predictive models aiding the assessor; and (3) the cost generated by the difference between the a-priory choice and the a-posteriori outcome