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181.
Shahla Asiri Reza FadayeVatan Maryam Rassouli Ali Montazeri 《Educational gerontology》2013,39(10):636-644
ABSTRACTThe psychosocial theory of Gerotranscendence, is proposing an alternative and positive view of aging and states that human development is a lifelong process. Applying the concept of Gerotranscendence into the older adults’ lives may have the potential to provide a more positive view of aging and a better care for a growing population. First; and to do this, we need to use a proper, valid and reliable measure. The purpose of this cross-sectional and methodological study was to assess the psychometric properties of the Persian version of the short-form Gerotranscendence scale (GS-S) in community-dwelling Iranian older adults. First the scale was translated to Persian, and culturally adapted. Then pre-testing and cognitive interviewing implemented in a sample consisted of 10; and stability of the scale in a sample of 30 older adults, respectively. Confirmatory factor analysis and internal consistency of the scale were done with 250 older adults. The three-factor structure was confirmed. The model showed a good fit, and all the indices were satisfactory (RMSEA = 0.063; NNFI = 0.093; CFI = 0.095; IFI = 0.096; GFI = 0.095; and χ2/df = 2). Cronbach’s alpha of the scale was 0.72 and coefficient omega was 0.82. Test-retest reliability (ICC) was 0.88, P < .001; and standard error of measurement was 1.16 (CI = %95). Minimal detectable change (MDC) was 3.2 and minimal important change (MIC) was 1.4. This study supports the use of the GS-S as a measure of life span development among the Iranian older adults. 相似文献
182.
183.
Saba Khan Roshan Alam Moinuddin Asif Ali 《Indian journal of clinical biochemistry : IJCB》2009,24(2):123-130
The present study was designed to probe the possible role of singlet oxygen and superoxide anion radical modified DNA in the
etiopathogenesis of Systemic lupus erythematosus. These species were generated by the exposure of riboflavin to 365 nm UV
light. Modified DNA showed single strand breaks, hyperchromicity at 260nm and decrease in Tm. The modified DNA induced high
titer antibodies in experimental animals. The antibodies showed reactivity with various nucleic acid polymers, a property
commonly associated with Systemic lupus erythematosus anti-DNA autoantibodies. Systemic lupus erythematosus sera showed preferential
binding of modified DNA over native DNA in direct binding and competitive binding solid phase immunoassays and band shift
assays. The results suggest for the possible involvement of the singlet- superoxide modified DNA as a potential trigger for
anti- DNA autoantibody production in SLE and thus in the etiopathogenesis of the disease. 相似文献
184.
Yazan M. Alsmadi Alaa M. Abdel-hamed Abo Eleyoun Ellissy Amged S. El-Wakeel Almoataz Y. Abdelaziz Vadim Utkin Ali Arshad Uppal 《Journal of The Franklin Institute》2019,356(8):4191-4214
This paper proposes an optimization scheme for optimal configuration and energy management of the micro-grid (MG), using the Cuckoo search optimization algorithm (CSOA). The selected MG supplies a load profile located between 30.119 latitude and 31.605 longitude. The energy produced by the MG generation sources, according to meteorological data of the proposed location, is calculated using MATLAB. The objective/fitness function is modeled and designed for minimizing the total investment cost (TIC) including capital, investment, operation and maintenance costs. A novel weighted goal attainment function (WGAF) has been proposed to reduce CO2 emissions and their associated costs. Moreover, WGAF also applies higher taxes on the amount of emissions that exceed governmental approved limits. To investigate the effects of WGAF on the TIC ($/year), annual cost of energy ($/kWh), and CO2 emissions, various weighted coefficients are analyzed. The simulation results have shown that the designed optimization scheme can robustly and efficiently produce the optimal MG configuration that is both eco-friendly and generates economic benefits. 相似文献
185.
Hajar Eftekhari Maryam Pilehchian Langroudi Ali Banihashemi Mandana Azizi Reza Youssefi Kamangar Haleh Akhavan-Niaki 《Indian journal of clinical biochemistry : IJCB》2018,33(2):231-234
α-Thalassemia (α-thal) is considered as the most common inherited hemoglobin disorder worldwide. The present study describes the first observation of a combination of rare α-chain variants, and β-globin gene cluster deletion. A 21-year-old woman with thalassemia trait, marked microcytosis, mild anemia, and normal range of Hb F was referred to Amirkola genetic center in the North of Iran for routine molecular test of thalassemia in the context of carrier detection and prevention of thalassemia major birth. Nucleotide sequencing revealed a novel compound heterozygosity status for two non-deletional mutations on HBA2, Hb O Indonesia (α116(GH4)Glu → Lys), and Hb Matsue–Oki (α75 (EF4) Asp → Asn), together with heterozygosity for the sicilian (δβ)0-thal mutation. This finding highlights the necessity of deep molecular investigation of thalassemia in regions where thalassemia is abundant, and present highly heterogeneous population. 相似文献
186.
Neyir Ozcan M. Syed Ali J. Yogambigai Quanxin Zhu Sabri Arik 《Journal of The Franklin Institute》2018,355(3):1192-1216
This paper is concerned with the problem of robust synchronization of a class of complex dynamical networks with time-varying delays and reaction–diffusion terms. To reflect most of the dynamical behaviors of the system, the parameter uncertainties are considered. A sampled-data controller with m stochastically varying sampling periods whose occurrence probabilities are given constants is considered. The control objective is that the trajectories of the system by designing suitable control schemes track the trajectories of the system with sample-data control. It is shown that, through Lyapunov stability theory, the proposed sample-data controllers are successful in ensuring the achievement of robust synchronization of complex dynamical networks even in the case of uncertainity and Markovian jumping parameters. By utilizing the Lyapunov functional method, Jensen’s inequality, Wirtinger’s inequality and lower bounds theorem, we establish a sufficient criterion such that, for all admissible parameter uncertainties, the complex dynamical network is robustly synchronized. The derived criteria are expressed in terms of linear matrix inequalities that can be easily checked by using the standard numerical software. Illustrative examples are presented to demonstrate the effectiveness and usefulness of the proposed results. 相似文献
187.
This study investigates how peer assessment contributes to enhancing student teachers' preparation during field experience. A semi-structured interview was conducted with 72 student teachers. The findings showed that the student teachers have positive beliefs about peer assessment. They think that it can be beneficial if some changes are made in the way it is employed in teacher education programs. In light of the study findings, the researchers put forth a number of suggestions and recommendations for employing peer assessment in teacher education programs in Jordan. 相似文献
188.
Ali Heydari 《Journal of The Franklin Institute》2017,354(11):4498-4518
The problem of optimal switching between different subsystems/configurations with minimum dwell time constraints is investigated in this study and a feedback solution, using the framework of approximate dynamic programming, is proposed. The method calls for a tuning stage in which parameters of a function approximator are tuned. Online control will then be conducted with a computational load as low as evaluating a few scalar-valued functions. Finite-horizon and infinite-horizon cost functions are investigated and convergence and stability are analyzed considering the presence of approximation errors. Moreover, the case of applying a full or partial constraint on the mode sequence, as well as having a mode-dependent minimum dwell time are investigated. Finally, performance of the scheme in handling different challenges is numerically evaluated through different examples. 相似文献
189.
This paper addresses the potentials of ultra-wideband (UWB) through-wall imaging radars compared with conventional narrowband systems. The challenges that limit the utilization of high precision UWB systems are examined with the aim of mitigating them. These challenges include multi-path, pulse dispersion, and antenna effects on the pulse shape due to angles of transmission and arrival. The propagation of UWB signals through walls is a crucial factor in determining the success of UWB radar technology. UWB signals, when propagating through walls, not only suffer attenuation but also distortion due to dispersive properties of the walls. This paper examines time- and frequency-domain techniques for measuring the electromagnetic properties of construction materials in the UWB frequency range. The measured parameters provide valuable insights in appreciating the capabilities and limitations of the UWB technology. Special attention is paid to time gating as a mean to extract the direct-path signal from the multi-path components. Both single-pass and multi-pass models are discussed. Multi-pass models account for the multiple reflections within the wall while the single-pass model assumes the possibility of gating out a single transmission. The partition-dependent narrowband propagation model is modified to account for the ultra-wide bandwidth of the signal. The paper illustrates the application of the modified model in indoor environments. The modified model is helpful in estimating the link power budget. It is also useful in studying the performance of UWB systems for indoor communication and positioning applications. 相似文献
190.
This paper presents a new method for the performance evaluation of bit decoding algorithms. The method is based on estimating the probability density function (pdf) of the bit log likelihood ratio (LLR) by using an exponential model. It is widely known that the pdf of the bit LLR is close to the normal density. The proposed approach takes advantage of this property to present an efficient algorithm for the pdf estimation. The moment matching method is combined with the maximum entropy principle to estimate the underlying parameters. We present a simple method for computing the probabilities of the point estimates for the estimated parameters, as well as for the bit error rate. The corresponding results are used to compute the number of samples that are required for a given precision of the estimated values. It is demonstrated that this method requires significantly fewer samples as compared to the conventional Monte-Carlo simulation. 相似文献