921 research outputs found
Synthesizing efficacious genistein in conjugation with superparamagnetic Fe<sub>3</sub>O<sub>4</sub> decorated with bio-compatible carboxymethylated chitosan against acute leukemia lymphoma
Abstract Background Genistein (C15H10O5) is a soy isoflavone with anti-cancer properties such as inhibition of cell growth, proliferation and tumor invasion, but effective dosage against hematopoietic malignant cells was not in non-toxic range. This property cause to impede its usage as chemotherapeutic agent. Therefore, this hypothesis raised that synthesizing biocompatible nanoparticle could assist to prevail this struggle. Methods Genistein covalently attached on Fe3O4 nanoparticles decorated with carboxymethylated chitosan to fabricate Fe3O4-CMC-genistein in alkaline circumstance. This obtained nanoparticles were evaluated by TEM, DLS, FTIR, XRD and VSM and its anti-cancer effect by growth rate and MTT assays as well as flow cytometer on ALL cancer cell lines. Results Different evaluations indicated that the drug delivery vehicle had a mean diameter size around 12ƞm with well bounded components. This system presented high degree of magnetization and superparamagnetic properties as well as good water solubility. In comparison with pure genistein, significant growth inhibition on hematopoietic cancer cells in lower dose of genistein nano-conjugated onto Fe3O4-CMC. It increased long lasting effect of genistein in cancer cells also. Conclusion This delivery system for genistein could be remarkably promised and futuristic as biocompatible chemotherapeutic agent against hematopoietic malignant cells
DEVELOPMENT AND VALIDATION OF TEACHER’S CULTURAL IDENTITY SCALE IN EFL CONTEXT: A STRUCTURAL EQUATION MODELING APPROACH
Due to the importance of culture in each society, several researchers have offered different definitions. Several studies have also been conducted on language, ego, ethnic, national, religious and modern identity. However, no validated model is proposed for Iranian cultural identity in English Foreign Language (EFL) contexts. Therefore, this research constitutes a relatively new area through developing and validating teacher’s cultural identity scale in the EFL context. Drawing on existing literature and various categorization of culture, the researchers used different sources, including Persian literature, social and cultural education, theology and history books to extract different components of culture. One hundred and thirty items were created primarily based on operational definitions of each component. The items were reviewed by a group of experts. After reviewing the items, the researchers piloted and tested the questionnaire using a sample of 305 EFL teachers. A final model of Iranian cultural identity with fifty-eight items underlying the eleven-factor model was specified in exploratory and confirmatory factor analysis. The reliability of items with Cronbach’s alpha (a=0.864) for the whole instrument was found to be adequate. Furthermore, the convergent and discriminate validity of the items has been found to be satisfactory
Analysis of Non-stationary Data for Heart-Rate Fluctuations in Terms of Drift and Diffusion Coefficients
We describe a method for analyzing the stochasticity in the non-stationary
data for the beat-to-beat fluctuations in the heart rates of healthy subjects,
as well as those with congestive heart failure. The method analyzes the returns
time series of the data as a Markov process, and computes the Markov time
scale, i.e., the time scale over which the data are a Markov process. We also
construct an effective stochastic continuum equation for the return series. We
show that the drift and diffusion coefficients, as well as the amplitude of the
returns time series for healthy subjects are distinct from those with CHF.
Thus, the method may potentially provide a diagnostic tool for distinguishing
healthy subjects from those with congestive heart failure, as it can
distinguish small differences between the data for the two classes of subjects
in terms of well-defined and physically-motivated quantities.Comment: 6 pages, two columns, 6 figure
Composite Blades of Wind Turbine: Design, Stress Analysis, Aeroelasticity, and Fatigue
In this chapter, four main topics in composite blades of wind turbines including design, stress analysis, aeroelasticity, and fatigue are studied. For static analysis, finite element method (FEM) is applied and the critical zone is extracted. Moreover, geometry, layup, and loading of the turbine blades made of laminated composites are calculated and evaluated. Then, according to the stress analysis, critical layer is specified and safety factor is studied based on Tsai-Wu failure criterion. Aeroelasticity is the main source of instability in structures that are subjected to aerodynamic forces. One of the major reasons of instability is the coupling of bending and torsional vibration of flexible bodies, which is known as flutter and considered in this study. Numerical and analytical methods are applied for considering the flutter phenomenon of the blades. For numerical method, the FEM and Joint Aviation Requirements (JAR-23) standard and for analytical method, two-degree freedom flutter and Lagrange’s equations are utilized. Also, lifetime prediction of a horizontal axis wind turbine composite blade is investigated. Accumulated fatigue damage modeling is employed as a damage estimation rule based on generalized material property degradation
Role of slanted reinforcement on bending capacity SS beams
The wide application range of simply supported beams in building construction, has always caused an attraction to somehow increase their bending capacity with high ductility. In this research, for the very purpose, the reinforcement bars under compression are bent at 45° from 1/3 of the beam length from the two ends and led to the tension zone. A sealed rubber tube of diameter twice that of the reinforcement bar covers the slanted part to separate it from the beam’s concrete. This will in fact reduce the stress intensity created in the bars above and below the neutral plane and increase the beam’s bending capacity considerably through making the two tensile and compressive forces acting opposite to each other. Actually, the proposed system can be specified by applying a superposition of the sum of the effects of the compressive stresses of the reinforcement bars above the beam’s 1/3 ends plus the sum of the effects of the tensile stresses created at 1/3 of the beam midpoint. The compressive stress created in the upper part tends to pass through the slanted part and reach the tensile part, and an opposite act for the tensile stress created in the lower part. Therefore, it is obvious that a compressive force found by the solution of the first superposition equation is applied at the middle 1/3 of the lower part and causes up to 25 % increase in the beam bending capacity
REFER: An End-to-end Rationale Extraction Framework for Explanation Regularization
Human-annotated textual explanations are becoming increasingly important in
Explainable Natural Language Processing. Rationale extraction aims to provide
faithful (i.e., reflective of the behavior of the model) and plausible (i.e.,
convincing to humans) explanations by highlighting the inputs that had the
largest impact on the prediction without compromising the performance of the
task model. In recent works, the focus of training rationale extractors was
primarily on optimizing for plausibility using human highlights, while the task
model was trained on jointly optimizing for task predictive accuracy and
faithfulness. We propose REFER, a framework that employs a differentiable
rationale extractor that allows to back-propagate through the rationale
extraction process. We analyze the impact of using human highlights during
training by jointly training the task model and the rationale extractor. In our
experiments, REFER yields significantly better results in terms of
faithfulness, plausibility, and downstream task accuracy on both
in-distribution and out-of-distribution data. On both e-SNLI and CoS-E, our
best setting produces better results in terms of composite normalized relative
gain than the previous baselines by 11% and 3%, respectively
The mediating effect of management accounting system on the relationship between contingent variables and managerial performance in Iran
Prior researches confirm that there is no unique and universal management accounting system (MAS) for all organizations, since this depends on internal firm characteristics and environmental features. Previous studies have also shown that, there has been a lack of empirical evidence on MAS researches in the service organizations, especially the financial organization. This study is an empirical investigation of the contingency theory, examining the relationship between contingency variables (market competition, technology and organization structure) and MAS characteristics on managerial performance. The focus of this study is mainly on four information characteristics of MAS – scope, integration, aggregation and timeliness. The scope of the study is the Iranian financial organizations which consist of banks, insurance companies and investment organizations. Managers of these organizations which include financial managers, chief accountants, chief financial controllers and chief financial officers were selected as respondents for the questionnaire survey. This study used the SmartPLS software version 2.0 to analyze the data, and the model of study was estimated with structural equation modeling (SEM). It followed the two-stage analytical procedures of SEM: assessing confirmatory measurement models (factor analysis) to make sure that the measurements used in this study are valid, and confirmatory structural models (path analysis) to determine relationships among the constructs. The study found the existence of direct relationships between these contingent variables and MAS, and between MAS and managerial performance. The study also confirmed that MAS acted as a mediator in the relationship between these contingent variables and managerial performance. The findings provide valuable insight to guide managers in financial organizations to improve their performance through suitable MAS by considering internal and environmental factors. Recommendations on how to improve MAS and managerial performance are provided accordingly
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