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341.
Yvonne O’Connor Ciara Heavin Joe Gallagher John O’Donoghue 《Behaviour & Information Technology》2017,36(7):745-753
In relation to mobile health (mHealth) initiatives, early engagement by potential end users has been established to have a positive impact both in the medium- to long-term adoption of the solution. However, there remains a paucity of research which focuses on participant recruitment for mHealth initiatives in developing countries. The objective of this paper, therefore, is to examine community health workers’ (CHWs’) intentions to participate in a mHealth pilot study in Malawi, Africa. A conceptual model with three characteristics is derived from the existing literature which may influence a CHW’s intentions: namely, (1) participant, (2) pilot study, and (3) social and contextual characteristics. A paper-based survey of CHWs was employed to examine the model, analysed using the partial least squares method of structural equation modelling. This study reveals that participant and pilot study characteristics primarily influence the decision-making process of CHWs when considering their participation in pilot studies. Health policy-makers and professionals should focus on reducing uncertainty by promoting the importance of the study at individual and societal levels and ensuring that potential end users are competent interacting and using mHealth. 相似文献
342.
Madhumita Bhaumik Taile Yvonne Leswifi Arjun Maity V.V. Srinivasu Maurice S. Onyango 《Journal of hazardous materials》2011
Polypyrrole (PPy)/Fe3O4 magnetic nanocomposite as a novel adsorbent was prepared via in-situ polymerization of pyrrole (Py) monomer using FeCl3 oxidant in aqueous medium in which Fe3O4 nanoparticles were suspended. The adsorbent was characterized by Attenuated Total Reflectance Fourier transform infrared spectroscope (ATR-FTIR), Brunauer–Emmet–Teller (BET) method, field emission scanning electron microscope (FE-SEM), high resolution transmission electron microscope (HR-TEM), X-ray photoelectron spectroscope (XPS) and X-ray diffraction (XRD). Magnetic property of the adsorbent was measured by electron spin resonance (ESR). Subsequently, the ability of the adsorbent to remove fluoride ions from aqueous solution was demonstrated in a batch sorption mode. Results reveal that the adsorption is rapid and that the adsorbent has high affinity for fluoride, which depends on temperature, solution pH and adsorbent dose. From equilibrium modelling, the equilibrium data is well described by Freundlich and Langmuir–Freundlich isotherms while the adsorption kinetics is described by the pseudo-second-order model. Thermodynamic parameters confirm the spontaneity and endothermic nature of the fluoride adsorption. Meanwhile, the fluoride adsorption proceeds by an ion exchange mechanism. 相似文献
343.
Phenolic‐enriched fractions from brewers' spent grain possess cellular antioxidant and immunomodulatory effects in cell culture model systems 下载免费PDF全文
344.
Aoife L. McCarthy Yvonne C. O’Callaghan Susanne Neugart Charles O. Piggott Alan Connolly Marcel A.K. Jansen Angelika Krumbein Monika Schreiner Richard J. FitzGerald Nora M. O’Brien 《Food chemistry》2013
The hydroxycinnamic acid (HA) content of starting barley for brewers’ spent grains (BSG), whole BSG and phenolic extracts from BSG was measured using high performance liquid chromatography (HPLC) and correlated with antioxidant potential. The effect of BSG phenolic extracts on antioxidant activity of fruit beverages was also assessed (using the total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays). The concentration of HA present in barley extract and BSG was in the order of ferulic acid (FA), p-coumaric acid (p-CA) derivatives, FA derivatives, p-CA, caffeic acid (CA) and CA derivatives. Results suggested that brewing and roasting decreased the HA content. Antioxidant activity was significantly (P < 0.05) correlated with caffeic acid (R2 = 0.8309) and total HA (R2 = 0.3942) concentrations. Addition of extracts to fruit beverages resulted in a significant (P < 0.05) increase in antioxidant activity of cranberry juice, measured by the FRAP assay. In vitro digestion significantly (P < 0.05) reduced TPC, DPPH and FRAP activity of the fruit beverages. 相似文献
345.
Yvonne Y. Murevanhema Victoria A. Jideani 《Critical reviews in food science and nutrition》2013,53(9):954-967
Bambara groundnut (Vigna subterraenea (L.) verdc) (BGN) is a legume; its origin have been traced back to Africa, and it is the third important legume; however, it is one of the neglected crops. It is highly nutritious, and has been termed a complete food. Its seed consist of 49%–63.5% carbohydrate, 15%–25% protein, 4.5%–7.4% fat, 5.2%–6.4% fiber, 3.2%–4.4% ash and 2% mineral compared to whole fresh cow milk 88% moisture, 4.8% carbohydrate, 3.2% proteins, 3.4% fat, 0.7% ash, and 0.01% cholesterol. Its chemical composition is comparable to that of soy bean. Furthermore, BGN has been reported to be a potential crop, owing to its nutritional composition, functional properties, antioxidant potential, and a drought resistant crop. Bambara groundnut milk (BGNM) had been rated higher in acceptability than milk from other legumes like soybean and cowpea. Probiotics have been defined as live microorganisms which when administered in adequate amount confer a health benefit on the host. These benefits have been reported to be therapeutic, suppressing the growth and activity in conditions like infectious diarrhea, irritable bowel syndrome, and inflammatory bowel disease. The nutritional profile of BGNM is high enough to sustain the growth of probiotics. BGNs are normally boiled and salted, eaten as a relish or roasted, and eaten as a snack. Hence, BGNM can also be fermented with lactic acid bacteria to make a probiotic beverage that not only increase the economic value of the nutritious legume but also help in addressing malnutrition. 相似文献
346.
Danielle Wilde Eric Harris Yvonne Rogers Cliff Randell 《Personal and Ubiquitous Computing》2003,7(3-4):227-233
This paper describes an interactive device, the Periscope, designed to be used as an educational tool featured during a children's digitally enhanced field trip in a woodland setting. The Periscope assembly, including a display and RFID equipped tangibles, is controlled using handles that enable it to be raised and rotated. The display is controlled by rotating the Periscope, or alternatively by twisting the handles. A set of tangibles, a collection of Petri dishes fitted with RFID tags, enable the children to carry out experiments with the results being shown on the display. Field trials are also outlined in which the effectiveness of this design is established. In conclusion, we discuss the aesthetic design issues raised by introducing digital technology into everyday environments. 相似文献
347.
Ulrich Peuchert Yoshio Okano Yvonne Menke Steffen Reichel Akio Ikesue 《Journal of the European Ceramic Society》2009,29(2):283-291
Optical transparent polycrystalline ZrO2 ceramics were fabricated by solid-state sintering process using first vacuum sintering followed by hot isostatic pressing. In the visible wavelength range (400–800 nm), the in-line transmittance of 5.6-mm thick samples reaches 68% at exemplary wavelength 600 nm (corresponding to an in-line absorbance based on 10 of A10 = 0.08 cm?1), which is approximately 90% of theoretical limit. The refractive indices of the ZrO2 optoceramics at 630 nm (nd) are varying between 2.10 and 2.20, depending on TiO2 contents, the latter being used as sintering aid. The appearance of birefringence is strongly correlated to the addition of TiO2 as sintering additive in the ceramic samples, whereas addition of TiO2 and simultaneous increase in Y2O3 content resulted in a decrease of birefringence. 相似文献
348.
349.
This article conceptualizes the phases of group development using Y. M. Agazarian's theory of living human systems (1997) and K. Lewin's field theory (1951). Linking these theories to operational models builds a bridge to research by making it possible to generate specific hypotheses. The basic systems-centered hypothesis can then be tested empirically: that weakening the restraining forces at the boundary between each subphase of system development releases the driving forces inherent in all living human systems, so that the system moves toward the next phase of development--in the direction of the inherent system goals of survival, development, and transformation. The discussion focuses on the implications for group leaders in organizations and therapeutic practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
350.
Johannes Solarek Christina Bachmann Yvonne Klemm Christos G. Aneziris Horst Biermann 《Journal of the American Ceramic Society》2016,99(4):1390-1397
Carbon‐bonded alumina with 33 wt% residual carbon was tested in compression at room temperature and at temperatures between 700°C and 1500°C in quasi‐static tests, creep tests, and stress relaxation tests. Therefore, a new high‐temperature test set up with inert gas chamber and inductive heating was used. The tests were accomplished by investigations of microstructure and Young's modulus. At room temperature, the results exhibit a pronounced hysteresis for the first loading cycle, which almost completely disappeared in subsequent cycles. The creep tests showed characteristic curves for compression whereas primary and secondary (stationary) creep occurred. Above 1000°C, a strong increase in creep rate was detected, whereas almost no creep was observed below this temperature. All creep curves were approximated with the models of logarithmic and Andrade creep. The activation energy for creep was found to be 263 kJ/mol above 1150°C. The resistance against stress relaxation showed an anomaly with a minimum between 1000°C to 1200°C and a maximum between 1300°C and 1400°C. 相似文献