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Removal of methylene blue by adsorption onto activated carbon developed from Ficus carica bast
No full textAbstractIn this study, activated carbon was developed from Ficus carica bast (FCBAC). The experiments were carried out to explore methylene blue (MB) uptake by FCBAC. The influence of various experimental factors such as contact time, initial dye concentration, adsorbent dosage, temperature and pH of dye solution was investigated. The adsorption equilibrium was represented with Langmuir, Freundlich and Temkin isotherm models. Langmuir and Tempkin equations were found to have the correlation coefficient value in good agreement. Adsorption of MB onto FCBAC followed pseudo second order kinetics. The calculated values of ΔH°, ΔS° and ΔG° were found to be 21.55kJ/mol, 76.24J/molK and −1.55kJ/mol, respectably. Adsorption process was spontaneous and endothermic in nature
Characterization of the particulate matter and relationship between buccal micronucleus and urinary 1-hydroxypyrene levels among cashew nut roasting workers
No full textAbstractThe present study is the first assessment of occupational risk associated with artisanal cashew nut roasting using exposure and effect biomarkers, as well as a characterization and dispersion analysis of the released particulate matter (PM). A real-time particle monitor was used to quantify PM1.0, PM2.5 and PM10. Furthermore, the PM was sampled using a Handi-vol sampler, and the physicochemical characteristics were determined by SEM-EDS analysis. Trajectories, dispersion and deposition of the emitted material were calculated using the NOAA-HYSPLIT model. Urinary 1-hydroxypyrene (1-OHP) levels were analyzed by HPLC. DNA damage, chromosomal instability and cell death were measured by a buccal micronucleus cytome assay (BMCyt). The PM concentrations for all measurements in the exposed area were higher than in the non-exposed area. SEM-EDS analyses exhibited a wide variety of particles, and K, Cl, S and Ca biomass burning tracers were the major inorganic compounds. In addition, atmospheric modeling analysis suggested that these particles can reach regions farther away than 40 kilometers. Occupational polycyclic aromatic hydrocarbon exposure was confirmed by increases in 1-OHP levels in cashew nut workers. Frequencies of BMCyt biomarkers of genotoxicity (micronuclei and nuclear bud) and cytotoxicity (pyknosis, karyolysis, karyorrhexis and condensed chromatin) were higher in the exposed group compared with the controls. The influence of factors, such as age, on the micronuclei frequencies was demonstrated, and a correlation between 1-OHP and micronuclei was observed. To the best of our knowledge, no other study has demonstrated a correlation between these types of biomarkers. The use of exposure (1-OHP) and effect (BMCyt) biomarkers were therefore efficient in assessing the occupational risk associated with artisanal cashew nut roasting, and the high rates of PM2.5 are considered to be a potential contributor to this effect
Oxidative aromatization of novel tetrahydrochromeno[4,3-b]quinolines using silica sulfuric acid/NaNO2
No full textAbstractA combination of silica sulfuric acid and sodium nitrite in the presence of wet SiO2 was used as an effective oxidizing agent for the oxidative aromatization of novel Tetrahydrochromeno[4,3-b]quinolines to their corresponding pyridine derivatives under reflux and heterogeneous conditions in high yields
Quiste mesentérico gigante asociado a colecistitis crónica litiásica y coledocolitiasis múltiple
No full textSafety assessment of Bacillus subtilis CU1 for use as a probiotic in humans
No full textAbstractBacillus subtilis CU1 is a recently described probiotic strain with beneficial effects on immune health in elderly subjects. The following work describes a series of studies supporting the safety of the strain for use as an ingredient in food and supplement preparations. Using a combination of 16S rDNA and gyrB nucleotide analyses, the species was identified as a member of the Bacillus subtilis complex (B. subtilis subsp. spizizenii). Further characterization of the organism at the strain level was achieved using random amplified polymorphic DNA polymerase chain reaction (RAPD PCR) and pulsed field gel electrophoresis (PFGE) analyses. B. subtilis CU1 did not demonstrate antibiotic resistance greater than existing regulatory cutoffs against clinically important antibiotics, did not induce hemolysis or produce surfactant factors, and was absent of toxigenic activity in vitro. Use of B. subtilis CU1 as a probiotic has recently been evaluated in a 16-week randomized, double-blind, placebo-controlled, parallel-arm study, in which 2 × 109 spores per day of B. subtilis CU1 were administered for a total 40 days to healthy elderly subjects (4 consumption periods of 10 days separated by 18-day washouts). This work describes safety related endpoints not previously reported. B. subtilis CU1 was safe and well-tolerated in the clinical subjects without undesirable physiological effects on markers of liver and kidney function, complete blood counts, hemodynamic parameters, and vital signs
The relationship between oral health and oral health related quality of life among elderly people in United Kingdom
No full textAbstractObjectivesTo identify the determinants of OHRQoL among older people in the United Kingdom.MethodsA subset of elderly (≥65year) participants from the UK Adult Dental Health Survey 2009 data was used. OHRQoL was assessed by means of the OHIP-14 additive score. The number of missing teeth; presence of active caries, dental pain, root caries, tooth wear, periodontal pockets>4mm, loss of attachment>9mm; having PUFA>0 (presence of severely decayed teeth with visible pulpal involvement, ulceration caused by dislocated tooth fragments, fistula and abscess); and wearing a denture were used as predictor variables. Age, gender, marital status, education level, occupation and presence of any long standing illness were used as control variables. Multivariate zero-inflated Poisson regression analysis was performed using R-project statistical software.ResultsA total of 1277 elderly participants were included. The weighted mean(SE) OHIP-14 score of these participants was 2.95 (0.17). Having active caries (IRR=1.37, CI=1.25;1.50), PUFA>0 (IRR=1.17, CI=1.05;1.31), dental pain (IRR=1.34, CI=1.20;1.50), and wearing dentures (IRR=1.30, CI=1.17;1.44), were significantly positively associated with OHIP-14 score. Having periodontal pockets>4mm, at least one bleeding site, and anterior tooth wear were not significantly associated with the OHIP-14 score.ConclusionWhereas previous research has suggested a moderate relationship between oral disease and quality of life in this large scale survey of older adults, the presence of active caries and the presence of one or more of the PUFA indicators are associated with impaired oral health related quality of life in older adults, but not indicators of periodontal status. The implication of this is that whilst focussing on prevention of disease, there is an ongoing need for oral health screening and treatment in this group
Design and operation of a Tesla-type valve for pulsating heat pipes
No full textAbstractA new Tesla-type valve is successfully designed for promoting circulation in a pulsating heat pipe (PHP) and improving the thermal resistance. Its functionality and diodicity is tested by laminar single-phase modelling and by steady two-phase flow experiments. The valve is symmetrically integrated in a single-turn PHP, which reduces variabilities to give a more thorough understanding of the behaviour in PHPs. Two transparent bottom-heated PHPs, one with and one without valves, are manufactured and the flow behaviour and thermal performance is studied. The valves produced a diodicity which lead to a difference in velocity of 25% for the different flow directions. Furthermore, a decrease of 14% in thermal resistance was observed due to the addition of the valves
Seeing light at the end of the tunnel: Positive prospective mental imagery and optimism in depression
No full textAbstractOptimism is associated with positive outcomes across many health domains, from cardiovascular disease to depression. However, we know little about cognitive processes underlying optimism in psychopathology. The present study tested whether the ability to vividly imagine positive events in one's future was associated with dispositional optimism in a sample of depressed adults. Cross-sectional and longitudinal analyses were conducted, using baseline (all participants, N=150) and follow-up data (participants in the control condition only, N=63) from a clinical trial (Blackwell et al., 2015). Vividness of positive prospective imagery, assessed on a laboratory-administered task at baseline, was significantly associated with both current optimism levels at baseline and future (seven months later) optimism levels, including when controlling for potential confounds. Even when depressed, those individuals able to envision a brighter future were more optimistic, and regained optimism more quickly over time, than those less able to do so at baseline. Strategies to increase the vividness of positive prospective imagery may aid development of mental health interventions to boost optimism
Testing an integrated destination image model across residents and tourists
No full textAbstractTourism research has yet to confirm whether an integrated destination image model is applicable in predicting the overall destination image and behavioral intentions of local residents. This study examines whether the cognitive, affective and overall image - hypothesized to be predictors of behavioral intentions - are applicable to residents and tourists in the resort city of Eilat. The proposed model allowed for the distinct effect of each image component on overall image and behavior to be closely examined. The findings support the applicability of the model to local residents and also showed that among tourists, the affective component exerted a greater influence than the cognitive on overall destination image and future behavior. These findings have theoretical and practical implications for research on destination image