Elastic properties of TeO2-B2O3—ZnO-Gd2O3 glasses using non-destructive ultrasonic technique

The addition of Gd2O3 causes the glass system to be highly ionic resulting in increasing rigidity and the tendency of devitrification. Gd2O3 affects the strength governing the elastic properties of the glass. The elastic moduli of the prepared glasses are expected to increase with the addition of the Gd2O3 due to increasing net molecular weight of prepared glass resulting in strong connectivity and more compactness of the glass network. The objective of this present work is to study the elastic properties of TeO2-B2O3-ZnO doped Gd2O3 using a non-destructive ultrasonic technique. A series of {[(TeO2)0.7(B2O3)0.3]0.7(ZnO)0.3}1-x(Gd2O3)x glasses with x = 0.01, 0.02, 0.03, 0.04 and 0.05 mol were prepared by conventional melt-quenching method. Both longitudinal and shear ultrasonic velocities were measured using a pulse-echo method at a frequency of 5 MHz at room temperature. The elastic moduli (longitudinal modulus, shear modulus, Young’s modulus and Bulk modulus), Poisson’s ratio, Debye temperature, micro-hardness and softening temperature have also been quantified. The experimental results show that the elastic properties depend on the composition of the glass systems and the role of Gd2O3inside the glass network

Evaluation of Telehealth Equipment

The aim of the project was to evaluate the use of Telehealth equipment in the homes of older community-dwelling people, and to review its social and economic impact. A mixed methods approach was adopted, involving interviews, observation and Depression Anxiety Stress Scales. The overall impression gained from participants was an enhancement to the self-perceived quality of daily functioning. Less benefit was observed by those who had been self-monitoring previously. The greatest benefit was apparent in those participants where changes in behaviours to prevent an exacerbation of their condition was possible, through either better compliance with medication, or better understanding the impact of medication on their vital signs and what that meant to their daily activities. The economic benefits appear to be linked to that social improvement. A greater focus on specific conditions and the ability to achieve stability in self-management could strengthen the evidence for targeted economic benefits

Structural and optical properties of Tm2O3-doped zinc borotellurite glass system

Thulium doped zinc borotellurite glasses with composition {[(TeO2)0.7(B2O3)0.3]0.7[ZnO]0.3}1-x{Tm2O3}x were synthesized using melt-quenching technique. The values of x varied from 0.01 to 0.05 mol. The density and molar volume of the glass samples were found to increase with increased concentration of thulium oxide. FTIR analysis showed the existence of TeO4, BO3 and BO4 structural units in the glass network as well as the formation of bridging oxygens. XRD patterns confirmed the amorphous nature of the glass and were supported by the absence of sharp edges in the absorption spectra. All the optical data was found to vary with the concentration of Tm2O3. The direct and indirect optical band gap was in the range of 4.19 to 4.38 eV and 3.62 to 3.79 eV respectively. The trend for refractive index, molar refraction and molar polarizability was in opposite trend to the optical band gap and Urbach energy due to the variation of non-bridging oxygens (NBOs), increment of cross-link density, and also the existence of free electrons in the glass system

Optical properties of zinc borotellurite glass system doped with erbium and erbium nanoparticles for photonic applications

t Comparative analysis on optical properties between two glass series (a—ordinary glass, b—glass with nanoparticles) have been estimated. The two glass series (a—ordinary glass, b—glass with nanoparticles) with compositions {[(TeO2)0.70 (B2O3)0.30]0.70 (ZnO)0.30}1-y (Er2O3/Er2O3 nanoparticles)y; y = 0.005, 0.01, 0.02, 0.03, 0.04, 0.05 mol% were successfully prepared by using meltquenching method. The TEM, EDX and XRD have been used to confirm the existence of nanoparticles and all elements in the glass system. The density of b—glass with nanoparticles are found greater than a—ordinary glass. The optical properties of the glass series were characterized by using Ellipsometer and UV–Vis spectrophotometer. There is a linear increasing trend in refractive index of the glass series along with concentration of erbium and erbium nanoparticles oxide. The refractive index of b—glass with nanoparticles is greater than a—ordinary glass. Moreover, the absorption peaks of a—ordinary glass are more intense than b—glass with nanoparticles. The glass with nanoparticles will offer a potential materials for nanophotonic devices

Comprehensive study on the nonlinear optical properties of lanthanum nanoparticles and lanthanum oxide doped zinc borotellurite glasses

Recently, the rapid growth in photonic field has increased the demand for nonlinear materials with higher performance and greater efficiency. Hence, a thorough investigation on the nonlinear optical properties of materials are essential and need to be done for possible future application of the material in photonic field as optical limiting or optical switching devices. Thus, through this research, the crucial parameters in nonlinear optical properties of zinc borotellurite glasses doped with lanthanum oxide and lanthanum nanoparticles were studied and investigated extensively. The two series of glasses were successfully fabricated via conventional melt-quenching technique. The fabricated samples were characterized by using Fourier Transform Infra-Red (FTIR) spectroscopy as well as Z-scan technique in order to study the structural and nonlinear optical properties of the glass systems. The existence of various amount of TeO4, TeO3, BO4 and BO3 in all the prepared glasses are proven through the observable absorption bands in the FTIR spectra. Inconsistent trends recorded for both nonlinear absorption coefficient and nonlinear refractive index might be associated with the simultaneous creation of bridging as well as nonbridging oxygen which eventually affect the values for both parameters. The figure of merit of the prepared glasses with values ranging from 0.055 to 0.267 which are smaller than one hints that the glass materials possess potential to be employed as all optical devices. 0.03 M fraction of lanthanum nanoparticles doped zinc borotellurite with FOM value larger than 1 has proven the ability of the respective glass to be employed as efficient all optical switching devices. The determined nonlinear optical parameters of the glasses should be able to provide sufficient and useful information on the fabricated glass samples for future application in photonic field

Evaluating the social and economic value of the use of telehealth technology to improve self-management by older people living in the community

Abstract: The aim of the project was to evaluate the use of Telehealth equipment in the homes of older community dwelling people, and to review its social and economic impact. A mixed methods approach was adopted, involving interviews, observation and Depression Anxiety Stress Scales. Overall, the greatest benefit was apparent in those participants with a low familiarity with technology and low digital literacy, where changes in behaviours to prevent an exacerbation of their condition was possible. The user-interface design reduced concern about using the technology. Changes achieved were through better compliance with medication and associated understanding of the impact on their vital signs and hence daily activities. This represented an improved health literacy and the economic benefits appear to be linked to that. Less benefit was observed by those who had been self-monitoring previously. A greater focus on specific conditions and improved self-management could strengthen the evidence for targeted economic benefits

Serum brain-derived neurotrophic factor (BDNF) and self-paced time-trial performance in older untrained men.

PurposeThis study examined the effect of 12 weeks of concurrent aerobic and resistance training on brain derived neurotrophic factor (BDNF) levels, neuromuscular performance and cerebral oxygenation on self-paced cycling exercise in previously untrained older men.MethodsEight untrained healthy males aged 53-64 years performed a familiarisation and a pre-training self-paced cycling time trial before 12 weeks of exercise training which combined aerobic and resistance exercise. The self-paced cycling time trial comprised a 30 s maximal effort sprint for every 4.5 min of lower intensity pace for a total of 25 min. Upon completion of 12 weeks of training, a comparison of the pre-training trial analysed for serum BDNF, neuromuscular performance, and cerebral oxygenation was undertaken.ResultsSerum BDNF decreased significantly from 10.02 ± 4.63 to 6.96 ± 3.56 ng/ml after 12 weeks of training. There was also attenuated physiological strain for a comparable self-paced cycling performance. Despite positive physiological responses during the time trial pacing strategy was not altered compared with pre training.ConclusionBDNF decreases following 12 weeks of concurrent training and might reflect neuroplasticity for this type of training stimulus. Exercise training in previously sedentary older men can result in a multitude of physical benefits, which may also confer a neuroprotective effect. However, specific training is required to improve pacing strategies in previously untrained older males.Clinical trial registrationAustralian New Zealand Clinical Trials Registry number ACTRN12622001477718

Linear and nonlinear optical properties of Gd3+ doped zinc borotellurite glasses for all-optical switching applications

In this work, linear and nonlinear optical parameters of zinc borotellurite glasses doped with Gd3+ have been studied for all-optical switching applications. A series of gadolinium zinc borotellurite glasses were synthesized by using conventional melt quenching technique. Optical absorption spectra were recorded by UV–vis spectroscopy. From the optical absorption spectra, the cut-off wavelength, optical band gap, Urbach energy and refractive index have been determined and are related to the structural changes in the glass systems. The nonlinear optical properties of Gd3+ doped glasses are investigated by using Z-scan technique. The values of nonlinear refractive index and absorption coefficient with closed and opened apertures of the Z-scan, respectively, were determined for proper utilization in nonlinear optical devices. Keywords: Gadolinium, Rare earth, Borotellurite glass, Optical band gap, Refractive index, Nonlinear optical propertie

The impact of telehealth technology on user perception of wellbeing and social functioning, and the implications for service providers

The aim of the project was to evaluate the use of telehealth equipment in the homes of older community-dwelling people, and to review its social and economic impact. A mixed methods approach was adopted, involving interviews, observation and Depression Anxiety Stress Scales. Overall, the greatest benefit was apparent in those participants with a low familiarity with technology and low digital literacy, where changes in behaviours to prevent an exacerbation of their condition was possible. The user interface design reduced concern about using the technology. Changes achieved were through better compliance with medication and associated understanding of the impact on their vital signs and hence daily activities. This represented an improved health literacy and the economic benefits appear to be linked to that. Less benefit was observed by those who had been self-monitoring previously. A greater focus on specific conditions and improved self-management could strengthen the evidence for targeted economic benefits