1,238 research outputs found
Synthesis and application of hetaryl disazo disperse dyes derived from 4-amino-2-chloro-6,7-dimethoxyquinazoline and 3-chloroaniline on polyester fabric
In an attempt to find more environmentally friendly azo dyes, the synthesis and application of disazo disperse dye derivatives of 4-amino-2-chloro-6,7-dimethoxyquinazoline and 3-chloroaniline on polyester fabric are reported. The disazo dyes were synthesized via diazotisation of 3- chloroaniline and coupled with 4-amino- 2-chloro-6,7-dimethoxyquinazoline to afford an intermediate azo dye. This intermediate was further diazotised in concentrated sulphuric acid and followed by coupling reactions with various coupling components such as 1,3-diyhydroxybenzene, 2-amino-6-methylbenzonitrile, 3-amino-5-methyl-prazole, 1-napthol and 7-methoxy- 2-naphthol to give the disazo disperse dyes. The basic fastness properties (light fastness wash fastness heat and rubbing fastness) of the dyes on polyester fibre were discussed in terms of their chemical structures. All the synthesized disazo disperse dyes were characterized on the basis of their spectral analyses, IR, 1H NMR, 13C NMR and UV-visible spectroscopic data. The light fastness results were observed to be good ratings (5) and very good ratings (5/6). The sublimation test results gave excellent ratings of (5). Also, it was found that the wash fastness property, which is an indicator whether a dye could have affinity for a textile fabric or not, have excellent ratings of 5. From these results, it can be concluded that the best of these disazo dye compounds could be commercially important in the textile industry.Keywords: Disazo dyes, disperse dyes, hetaryl compounds, fastness, polyester fib, quinazoline
Analysis and Performance Evaluation of Microbial Fuel Cells for Electricity Generation
This research work is focused on the analysis and performance evaluation of microbial fuel cells (MFCs) consisting of multiple one chamber connected in series and parallels for investigation of electricity generation. Using six units (i.e., unit A, unit B, unit C, unit D, unit E, unit F, unit G and unit H) stacked MFCs, the fuel cells were analyzed and evaluated for performance. The results obtained with a single unit microbial fuel cells show that, unit (A) produced an average power of 0.224mW, unit (B) an average power of 0.179mW, unit (C) an average power of 0.138mW, unit (D) an average power of 0.092mW, unit (E) an average power of 0.058mW, unit (F) an average power of 0.036mW, unit (G) an average power of 0.018mW, and unit (H) an average power of 0.005mW. It was observed that decrease in number of microbial fuel cells lead to a corresponding decrease in voltage and current generated, thus drop in power. Conversely, when the unit microbial fuel cells were connected together in series and parallel, improvement in power generation was recorded. An average power of 2.681mW and 2.572mW were obtained from series and parallel connection respectively.Keywords: Microbial fuel cells, anode, cathode, power, renewable energy, electricity generatio
Knowledge, use and sensory evaluation of red palm oil Ogi by caregivers in Makurdi, Nigeria
Vitamin A deficiency is one of the major public health challenges in many developing countries affecting mainly children under 5 years of age and contributes to severity of life-threatening infections such as diarrhoea and measles. Over the years, several effective strategies have been adopted to combat vitamin A deficiency with the attendant challenge of sustainability. Food-based approaches based on vitamin A-rich, locally available food sources are considered sustainable and could help in filling this gap. The use of red palm oil among other locally available pro-vitamin A foodstuffs is recommended for incorporation into complementary foods given to children under 5 years of age by health workers in Nigeria. This study was conducted to ascertain the level of awareness, use and sensory evaluation of red palm oil ogi (a cereal-based porridge) by caregivers of under-fives within Makurdi, Nigeria. Data were obtained through a cross-sectional survey and two focus group discussions. The survey involved 100 respondents that were purposively sampled from three well patronized health facilities rendering post-natal services in Makurdi. The results of the survey were analyzed using descriptive statistics. The focus group discussions involved 17 members in two separate groups and responses were sorted and summarized. The results show that though caregivers consider red palm oil as a taboo-free cooking ingredient, knowledge on its use in ogi was low (11%). However, some caregivers were willing to adopt red palm oil ogi provided the method of preparation is demonstrated and presents no adverse effects on the child. Ogi prepared with 5 and 10% red palm oil (w/v) scored 6.8 and 6.6 for maize, 5.9 and 6.0 for millet, respectively for overall acceptability on a 9-point Hedonic scale while ogi without red palm oil was the most acceptable. This study has identified low awareness in the use of red palm oil ogi among caregivers of under-fives in Makurdi; ignorance about red palm oil’s nutritional benefits and appropriate preparation methods as well as actual concentration of red palm oil to be employed as some of the critical gaps in the use of red palm oil ogi in alleviating the burden of vitamin A deficiency among children under 5 years of age in Makurdi, Nigeria.Key words: Knowledge, Red palm oil, Og
Prediction Models for Water Erosion Risk Management: A Review
In order to estimate the potential soil erosion hazard of an area, erosion prediction models are needed. Various models have been used by researchers, which ranges from mathematical and conceptual simple approaches to complex models that try to include the complexities of the real world. Six (6) models are reviewed in relation to their suitability for use. The KINEROS, CORINE and EUROSEM were best suited for water erosion risk prediction in cultivated soils. On the other hand, the KINEROS, PESERA, CORINE and EUROSEM were found to be applicable in all sectors (Agronomy, water resources management and road construction) highlighted. The GLASOD had the least applicability with respect to this study.Keywords: Water Erosion, sediment transport models, Model structure and suitability for us
The effects of responsible gambling pop-up messages on gambling behaviors and cognitions: a systematic review and meta-analysis
Pop-up messages utilized by gambling operators are normally presented to gamblers during gambling sessions in order to prevent excessive gambling and/or to help in the appraisal of maladaptive gambling cognitions. However, the effect of such messages on gambling behavior and gambling cognitions has not previously been synthesized quantitatively. Consequently, a meta-analysis estimating the efficacy of pop-up messages on gambling behavior and cognitions was conducted. A systematic literature search with no time constraints was performed on Web of Science, PsychInfo, Medline, PsychNET, and the Cochrane Library. Search terms included “gambling,” “pop-up,” “reminder,” “warning message,” and “dynamic message.” Studies based on randomized controlled trials, quasi-experimental designs and pre-post studies reporting both pre- and post-pop-up data were included. Two authors independently extracted data using pre-defined fields including quality assessment. A total of 18 studies were included and data were synthesized using a random effects model estimating Hedges’ g. The effects of pop-ups were g = 0.413 for cognitive measures (95% CI = 0.115–0.707) and g = 0.505 for behavioral measures (95% CI = 0.256–0.746). For both outcomes there was significant between-study heterogeneity which could not be explained by setting (laboratory vs. naturalistic) or sample (gambler vs. non-gamblers). It is concluded that pop-up messages provide moderate effects on gambling behavior and cognitions in the short-term and that such messages play an important role in the gambling operators’ portfolio of responsible gambling tools
Limited Effects of Set Shifting Training in Healthy Older Adults
Our ability to flexibly shift between tasks or task sets declines in older age. As this decline may have adverse effects on everyday life of elderly people, it is of interest to study whether set shifting ability can be trained, and if training effects generalize to other cognitive tasks. Here, we report a randomized controlled trial where healthy older adults trained set shifting with three different set shifting tasks. The training group (n = 17) performed adaptive set shifting training for 5 weeks with three training sessions a week (45 min/session), while the active control group (n = 16) played three different computer games for the same period. Both groups underwent extensive pre-and post-testing and a 1-year follow-up. Compared to the controls, the training group showed significant improvements on the trained tasks. Evidence for near transfer in the training group was very limited, as it was seen only on overall accuracy on an untrained computerized set shifting task. No far transfer to other cognitive functions was observed. One year later, the training group was still better on the trained tasks but the single near transfer effect had vanished. The results suggest that computerized set shifting training in the elderly shows long-lasting effects on the trained tasks but very little benefit in terms of generalization
Superconducting Sr2RuO4 Thin Films without Out-of-Phase Boundaries by Higher-Order Ruddlesden-Popper Intergrowth
Ruddlesden-Popper (RP) phases (An+1B n O3n+1, n = 1, 2,···) have attracted intensive research with diverse functionalities for device applications. However, the realization of a high-quality RP-phase film is hindered by the formation of out-of-phase boundaries (OPBs) that occur at terrace edges, originating from lattice mismatch in the c-axis direction with the A'B'O3 (n = ∞) substrate. Here, using strontium ruthenate RP-phase Sr2RuO4 (n = 1) as a model system, an experimental approach for suppressing OPBs was developed. By tuning the growth parameters, the Sr3Ru2O7 (n = 2) phase was formed in a controlled manner near the film-substrate interface. This higher-order RP-phase then blocked the subsequent formation of OPBs, resulting in nearly defect-free Sr2RuO4 layer at the upper region of the film. Consequently, the Sr2RuO4 thin films exhibited superconductivity up to 1.15 K, which is the highest among Sr2RuO4 films grown by pulsed laser deposition. This work paves the way for synthesizing pristine RP-phase heterostructures and exploring their unique physical properties
Route knowledge and configural knowledge in typical and atypical development: a comparison of sparse and rich environments
Background:
Individuals with Down syndrome (DS) and individuals with Williams syndrome (WS) have poor
navigation skills, which impact their potential to become independent. Two aspects of navigation were investigated
in these groups, using virtual environments (VE): route knowledge (the ability to learn the way from A to B by
following a fixed sequence of turns) and configural knowledge (knowledge of the spatial relationships between
places within an environment).
Methods:
Typically developing (TD) children aged 5 to 11 years (N = 93), individuals with DS (N = 29) and individuals
with WS (N = 20) were presented with a sparse and a rich VE grid maze. Within each maze, participants were asked to
learn a route from A to B and a route from A to C before being asked to find a novel shortcut from B to C.
Results:
Performance was broadly similar across sparse and rich mazes. The majority of participants were able to learn
novel routes, with poorest performance in the DS group, but the ability to find a shortcut, our measure of configural knowledge, was limited for all three groups. That is, 59 % TD participants successfully found a shortcut, compared to 10 % participants with DS and 35 % participants with WS. Differences in the underlying mechanisms associated with route knowledge and configural knowledge and in the developmental trajectories of performance across groups were observed. Only the TD participants walked a shorter distance in the last shortcut trial compared to the first, indicative of
increased configural knowledge across trials. The DS group often used an alternative strategy to get from B to C, summing the two taught routes together.
Conclusions:
Our findings demonstrate impaired configural knowledge in DS and in WS, with the strongest deficit in DS. This suggests that these groups rely on a rigid route knowledge based method for navigating and as a result are
likely to get lost easily. Route knowledge was also impaired in both DS and WS groups and was related to different underlying processes across all three groups. These are discussed with reference to limitations in attention and/or visuo-spatial processing in the atypical groups
Goal Priming in Dieters: Recent Insights and Applications
What are the psychological mechanisms that make dieting so challenging in our food-rich living environment? Social psychological research on goal priming provides a useful framework for answering this question, as well as implications for how to enhance dieting success. This review presents and discusses recent research which shows that attractive food cues prime the hedonic eating goal in dieters, and thus facilitate overeating. However, external cues priming the goal of weight control can be used to offset these effects and thus to facilitate dieting success, as is demonstrated in both field and laboratory experiments. In addition, recent strategies to prevent hedonic effects of attractive food, such as mindful attention, can facilitate self-regulation. These recent advances in our understanding of dieting behavior have theoretical and practical implications for how successful dieting can be facilitated, both by means of individual strategies, as well as by environmental changes
International collaborative project to compare and track the nutritional composition of fast foods
BackgroundChronic diseases are the leading cause of premature death and disability in the world with over-nutrition a primary cause of diet-related ill health. Excess quantities of energy, saturated fat, sugar and salt derived from fast foods contribute importantly to this disease burden. Our objective is to collate and compare nutrient composition data for fast foods as a means of supporting improvements in product formulation.Methods/designSurveys of fast foods will be done in each participating country each year. Information on the nutrient composition for each product will be sought either through direct chemical analysis, from fast food companies, in-store materials or from company websites. Foods will be categorized into major groups for the primary analyses which will compare mean levels of saturated fat, sugar, sodium, energy and serving size at baseline and over time. Countries currently involved include Australia, New Zealand, France, UK, USA, India, Spain, China and Canada, with more anticipated to follow.DiscussionThis collaborative approach to the collation and sharing of data will enable low-cost tracking of fast food composition around the world. This project represents a significant step forward in the objective and transparent monitoring of industry and government commitments to improve the quality of fast foods.<br /
- …