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The present study was an attempt to investigate the perceptions of the Iranian foreign language policy makers as articulated in Iran's foreign language policy document using a systemic functional linguistics approach. To this end, the type of processes and participants who have been used in Iran's foreign language policy document were identified and interpreted in light of the assumptions of systemic functional linguistics and the related literature. The findings point out that the foreign language education policy document is heavily influenced by and draws on well-entrenched ideological, historical, religious, and political discourses. Further interpretations show that the FLEP document is heavily influenced by what is referred to as the Islamic ideology and discourse. In addition, applying a systemic functional linguistics approach to the document also offers a host of other interesting information about the Iranian foreign language teaching policymakers underlying perceptions about foreign language teaching and issues of globalization and imperialism. The concept of agency and how it is deemed by the Iranian foreign language practitioners was another identified topic. An investigation of the National Document of Education that includes the FLEP document as one of its subsections further showed that teachers have been appropriately described as autonomous individuals who possess the required agency to conduct and direct the classroom learning and teaching processes. Investigations also provide information on the perceptions of the Iranian foreign language education policymakers about the age that students must begin the learning of a foreign language at school.

Background: The accurate and early distinction of glioblastomas (GBMs) from single brain metastases (BMs) provides a window of opportunity for reframing treatment strategies enabling optimal and timely therapeutic interventions. We sought to leverage physiologically sensitive parameters derived from diffusion tensor imaging (DTI) and dynamic susceptibility contrast (DSC)–perfusion-weighted imaging (PWI) along with machine learning-based methods to distinguish GBMs from single BMs. Methods: Patients with histopathology-confirmed GBMs (n = 62) and BMs (n = 26) and exhibiting contrast-enhancing regions (CERs) underwent 3T anatomical imaging, DTI and DSC-PWI prior to treatment. Median values of mean diffusivity (MD), fractional anisotropy, linear, planar and spheric anisotropic coefficients, and relative cerebral blood volume (rCBV) and maximum rCBV values were measured from CERs and immediate peritumor regions. Data normalization and scaling were performed. In the next step, most relevant features were extracted (non-interacting features), which were subsequently used to generate a set of new, innovative, high-order features (interacting features) using a feature engineering method. Finally, 10 machine learning classifiers were employed in distinguishing GBMs and BMs. Cross-validation and receiver operating characteristic (ROC) curve analyses were performed to determine the diagnostic performance. Results: A random forest classifier with ANOVA F-value feature selection algorithm using both interacting and non-interacting features provided the best diagnostic performance in distinguishing GBMs from BMs with an area under the ROC curve of 92.67%, a classification accuracy of 87.8%, a sensitivity of 73.64% and a specificity of 97.5%. Conclusions: A machine learning based approach involving the combined use of interacting and non-interacting physiological MRI parameters shows promise to differentiate between GBMs and BMs with high accuracy. [ABSTRACT FROM AUTHOR]

Writing as a multiple-step process is one of the most complex and demanding skills for graduate students to master. Foreign or second language learners who are required to write for academic purposes at the university level may even find it more demanding to master. One of the ways of decreasing the burden of mastering this skill for learners is mediation, using scaffolding techniques to teach writing. Hence, having a good understanding of the impact(s) of adopting mediating or scaffolding techniques in writing classes is absolutely indispensable. To this end, the present study employed an experimental research design to investigate the impact of mediation in the flipped writing classrooms of the students of medicine. To peruse this goal, 47 medical students were selected through purposive sampling and put into control and treatment groups. Medical students in the treatment group watched teacher-made video content(s) before their writing classes. The students in this group experienced organized-interactive writing group activities in their classes. Unlike the experimental group, the students in the control group received all the instructions in the classroom and were assigned homework. The findings obtained through the ANOVA and t-test indicated that the students in the experimental group significantly outperformed their counterparts in the control group in terms of their writing. A probable conclusion could be that by requiring students to study in advance and take responsibility for their learning, flipped classroom can provide the opportunity for learners to actively construct knowledge rather than receive the information passively in the classroom. Flipped classroom can also cultivate interactive class time for teachers and enable them to invest in more fruitful academic practices, instead of asking students to spend a substantial amount of time each week doing homework independently.

This study focuses on nonlinear vibrations and stability of doubly curved shells/panels. The thin-walled shell structure is assumed to be acted upon by external loads as well as parametric excitation. Using the first-order shear deformation Fülgge theory assumptions, governing equations of motion are derived for a general doubly curved geometry. Nonlinear components which are compatible with the Von-Karman kinematic assumptions are retained in the formulation and the rest of nonlinear components are neglected due to the fact that strains are assumed to be small and rotations to be moderate. The formulation can be readily reduced to any geometry including cylindrical shells and spherical panels, as benchmark examples in this study. Employing the Galerkin discretization approach and applying a modification to the Volmir assumption, a reduced order form of the original system is determined, which is shown to be a great representative of the original system with much more computational advantages. Using the method of multiple scales, the reduced order nonlinear governing equations are solved to discover the primary resonance, forced vibration characteristics and stability margins of thin-walled shells/panels under the action of parametric excitation. Several interesting findings on nonlinear behavior of cylindrical shells and spherical panels (as benchmark geometries) are presented while giving a demonstration of the accuracy and computational advantages of the proposed model. [ABSTRACT FROM AUTHOR]

Background: Classical literature has pointed at lateralization of the relationship between memory scores and cerebral hemisphere injury. Epilepsy studies have suggested an association between left hippocampal damage and verbal memory deficits, and between right hippocampal damage and visual memory deficits. We aimed to explore this concept in the context of tauopathy due to Alzheimer's disease. Method: we assessed 132 cognitively unimpaired (CU) older adults, and 44 cognitively impaired (CI), amyloid‐β positive individuals from the Translational Biomarkers in Aging and Dementia (TRIAD) cohort. All participants had amyloid‐PET with [18F]AZD4694 and tau‐PET with [18F]MK6240, verbal memory assessments with Rey Auditory Verbal Learning Test (RAVLT), and visual memory assessments with Aggie Figures Learning Test (AFLT). We conducted voxel‐wise analyses to explore the relationship between tau PET and memory modality. In addition, we run regression models with right or left tau temporal metaROI as predictor and memory scores as outcome variables. We entered global amyloid (PET), sex, age, years of education, ApoE status, grey matter volume and handedness as covariates. Finally, we used the laterality index (LI) to investigate correlations with memory modality. Right laterality is indicated by an LI below 0, while left laterality would be signaled by an LI above 0. Result: voxel‐wise analyses suggested a lateralized relationship between tau and visual memory scores on the right hemisphere, whereas tau and verbal memory scores were bilaterally associated. Regression analyses showed a trend towards a stronger relationship between temporal tau on the right and visual memory scores. The LI was significantly associated with visual memory performance. Further analyses showed that this relationship seems to be driven by tau positive individuals. Conclusion: visual memory performance might be more prominently affected by tau load on the right hemisphere in Alzheimer's disease. Furthermore, a hemispheric imbalance in the amount of tau is related to visual, but not verbal, memory scores. [ABSTRACT FROM AUTHOR]

In this study, a set of generalized nonlinear equations of motion for Timoshenko composite shafts is derived using the geometrically exact approach. These partial differential equations of motion are discretized by Galerkin method and the free vibration of an orthotropic spinning shaft with hinged-hinged boundary conditions is investigated using the multiple-scale method. We find that in the case of two mode discretization, composite couplings can have significant linear and nonlinear effects on the behavior of the shaft and that these effects were not predictable in the classical model. Also, in the investigating of composite layering we find that the effects of the fibers angle as well as the composite couplings can be noticeable, and these effects are greater in the case of the asymmetrical layering. [ABSTRACT FROM AUTHOR]

This paper proposes a monopole antenna with two-pair sleeves that is fed through a coplanar waveguide. The new structure is composed of a triangular radiator and sleeves in size of 40x 40x1.6 mm3. The suggested structure is constructed on an FR-4 PCB layer with a dielectric constant of ε r=4.3. The best results are obtained by parameters sweep study with the CST simulator. According to the results, the bandwidth range is 2.45-11 GHz, expressing that the compact design covers an ultrawide bandwidth. The optimized antenna is manufactured and the measurement outcome of the return loss is compared with the CST simulator results at various frequencies, representing a satisfactory consistency of simulation and measurement results. [ABSTRACT FROM AUTHOR]

INTRODUCTION: We set out to identify tau PET‐positive (A+T+) individuals among amyloid‐beta (Aβ) positive participants using plasma biomarkers. METHODS: In this cross‐sectional study we assessed 234 participants across the AD continuum who were evaluated by amyloid PET with [18F]AZD4694 and tau‐PET with [18F]MK6240 and measured plasma levels of total tau, pTau‐181, pTau‐217, pTau‐231, and N‐terminal tau (NTA‐tau). We evaluated the performances of plasma biomarkers to predict tau positivity in Aβ+ individuals. RESULTS: Highest associations with tau positivity in Aβ+ individuals were found for plasma pTau‐217 (AUC [CI95%] = 0.89 [0.82, 0.96]) and NTA‐tau (AUC [CI95%] = 0.88 [0.91, 0.95]). Combining pTau‐217 and NTA‐tau resulted in the strongest agreement (Cohen's Kappa = 0.74, CI95% = 0.57/0.90, sensitivity = 92%, specificity = 81%) with PET for classifying tau positivity. DISCUSSION: The potential for identifying tau accumulation in later Braak stages will be useful for patient stratification and prognostication in treatment trials and in clinical practice. Highlights: We found that in a cohort without pre‐selection pTau‐181, pTau‐217, and NTA‐tau showed the highest association with tau PET positivity.We found that in Aβ+ individuals pTau‐217 and NTA‐tau showed the highest association with tau PET positivity.Combining pTau‐217 and NTA‐tau resulted in the strongest agreement with the tau PET‐based classification. [ABSTRACT FROM AUTHOR]

Objectives: This study is aimed at examining the synergistic impact of motion and acquisition/reconstruction parameters on 18F‐FDG PET image radiomic features in non‐small cell lung cancer (NSCLC) patients, and investigating the robustness of features performance in differentiating NSCLC histopathology subtypes. Methods: An in‐house developed thoracic phantom incorporating lesions with different sizes was used with different reconstruction settings, including various reconstruction algorithms, number of subsets and iterations, full‐width at half‐maximum of post‐reconstruction smoothing filter and acquisition parameters, including injected activity and test–retest with and without motion simulation. To simulate motion, a special motor was manufactured to simulate respiratory motion based on a normal patient in two directions. The lesions were delineated semi‐automatically to extract 174 radiomic features. All radiomic features were categorized according to the coefficient of variation (COV) to select robust features. A cohort consisting of 40 NSCLC patients with adenocarcinoma (n = 20) and squamous cell carcinoma (n = 20) was retrospectively analyzed. Statistical analysis was performed to discriminate robust features in differentiating histopathology subtypes of NSCLC lesions. Results: Overall, 29% of radiomic features showed a COV ≤5% against motion. Forty‐five percent and 76% of the features showed a COV ≤ 5% against the test–retest with and without motion in large lesions, respectively. Thirty‐three percent and 45% of the features showed a COV ≤ 5% against different reconstruction parameters with and without motion, respectively. For NSCLC histopathological subtype differentiation, statistical analysis showed that 31 features were significant (p‐value < 0.05). Two out of the 31 significant features, namely, the joint entropy of GLCM (AUC = 0.71, COV = 0.019) and median absolute deviation of intensity histogram (AUC = 0.7, COV = 0.046), were robust against the motion (same reconstruction setting). Conclusions: Motion, acquisition, and reconstruction parameters significantly impact radiomic features, just as their synergies. Radiomic features with high predictive performance (statistically significant) in differentiating histopathological subtype of NSCLC may be eliminated due to non‐reproducibility. [ABSTRACT FROM AUTHOR]