Rate of validity, reliability and difficulty indices for teacher-designed exam questions in first year high school

The purpose of the research is to determine high school teachers’ skill rate in designing exam questions in mathematics subject. The statistical population was all of mathematics exam shits for two semesters in one school year from which a sample of 364 exam shits was drawn using multistage cluster sampling. Two experts assessed the shits and by using appropriate indices and z-test and chi-squared test the analysis of the data was done. We found that the designed exams have suitable coefficients of validity and reliability. The level of difficulty of exams was high. No significant relationship was found between male and female teachers in terms of the coefficient of validity and reliability but a significant difference between the difficulty level in male and female teachers was found (P<.001). It means that female teachers had designed more difficult questions. We did not find any significant relationship between the teachers’ gender and the coefficient of discrimination of the exams.The purpose of the research is to determine high school teachers’ skill rate in designing exam questions in mathematics subject. The statistical population was all of mathematics exam shits for two semesters in one school year from which a sample of 364 exam shits was drawn using multistage cluster sampling. Two experts assessed the shits and by using appropriate indices and z-test and chi-squared test the analysis of the data was done. We found that the designed exams have suitable coefficients of validity and reliability. The level of difficulty of exams was high. No significant relationship was found between male and female teachers in terms of the coefficient of validity and reliability but a significant difference between the difficulty level in male and female teachers was found (P<.001). It means that female teachers had designed more difficult questions. We did not find any significant relationship between the teachers’ gender and the coefficient of discrimination of the exams

Acidic Brønsted Ionic Liquids Catalyzed the Preparation of 1-((Benzo[d]thiazol-2-ylamino)(aryl)-methyl)naphthalen-2-ol Derivatives 1-[(1,3-Benzothiazol-2-ylamino)(aryl)methyl]- 2-naphthol

The acidic ionic liquids, triethylammonium hydrogen sulfate ([Et3NH]HSO4), 2-pyrrolidonium hydrogen sulfate ([Hnhp]HSO4), 3-methyl-1-sulfonic acid imidazolium chloride ([Msim]Cl), and 1-methylimidazolium hydrogen sulfate ([Hmim]HSO4) catalyzed three-component condensation reaction of aromatic aldehydes, 2-aminobenzothiazole, and β-naphthol to afford corresponding 1-((benzo[d]thiazol-2-ylamino)(aryl)-methyl)naphthalen-2-ol derivatives. The inexpensive and non-toxic ionic liquids can be reused several times without noticeable loss of their activities.KEYWORDS Aldehyde, 2-aminobenzothiazole, β-naphthol, ionic liquids, catalyst, green chemistry

A brief report on the relationship between self-control, video game addiction and academic achievement in normal and ADHD students

Background and aims: Over the last two decades, research into video game addiction has grown increasingly. The present research aimed to examine the relationship between video game addiction, self-control, and academic achievement of normal and ADHD high school students. Based on previous research it was hypothesized that there would be a relationship between video game addiction, self-control and academic achievement video game addiction, self-control and academic achievement would differ between male and female students, and the relationship between video game addiction, self-control and academic achievement would differ between normal students and ADHD students. Methods: The research population comprised first grade high school students of Khomeini-Shahr (a city in the central part of Iran). From this population, a sample group of 339 students participated in the study. The survey included the Game Addiction Scale (Lemmens, Valkenburg & Peter, 2009), the Self-Control Scale (Tangney, Baumeister & Boone, 2004) and the ADHD Diagnostic checklist (Kessler et al., 2007). In addition to questions relating to basic demographic information, students’ Grade Point Average (GPA) for two terms was used for measuring their academic achievement. These hypotheses were examined using a regression analysis. Results: Among Iranian students, the relationship between video game addiction, self-control, and academic achievement differed between male and female students. However, the relationship between video game addiction, self-control, academic achievement, and type of student was not statistically significant. Conclusions: Although the results cannot demonstrate a causal relationship between video game use, video game addiction, and academic achievement, they suggest that high involvement in playing video games leaves less time for engaging in academic work

Deep SELECTOR-JPEG: ADAPTIVE JPEG IMAGE COMPRESSION FOR COMPUTER VISION IN IMAGE CLASSIFICATION AND HUMAN VISION

Deep Neural Networks (DNNs) demonstrate excellent performance in many Computer Vision (CV) applications such as image classification. To meet storage/bandwidth requirements, the input images to these CV applications are compressed using lossy image compression standards, among which JPEG is the most common. Classical JPEG is designed to consider Human Vision (HV) and pays a little attention to CV, resulting in classification accuracy drop of DNNs, especially at high Compression Ratios (CRs). This work presents Deep Selector-JPEG, an adaptive JPEG compression method that simultaneously targets both image classification and HV. For each image, Deep Selector-JPEG selects a Quality Factor (QF) adaptively to compress the image so that a good trade-off between the Compression Ratio (CR) and DNN classifier Accuracy (Rate-Accuracy performance) can be achieved over a set of images for a variety of DNN classifiers while the PSNR of such compressed image is greater than a threshold value predetermined by HV with a high probability. Towards this end, Deep Selector-JPEG first defines a set of feasible QFs such that an image compressed at any QF within this set has PSNR greater than a predetermined threshold value with a high probability. For some images, multiple QFs within this set are suitable (ON) for compressing for a DNN classifier, which means compressing at these QFs at least maintains the ground truth rank of the original input for the DNN classifier. For a given image, Deep Selector-JPEG first determines the QFs that are ON among the set of feasible QFs. This problem is represented as a Multi-label Classification (MLC) problem since each image has multiple corresponding suitable QFs. We solve MLC using a binary relevance procedure, which involves training an independent binary DNN classifier for each QF within the feasible set to predict the ON/OFF labeling for each input image. Given a target CR, we empirically derive a subset of feasible QFs for this target CR and select the least QF that is ON in this set. Experimental results show that in comparison with the default JPEG, Deep Selector-JPEG indeed achieves better Rate-Accuracy performance over the entire ImageNet validation set for all tested DNN classifiers with gains in classification accuracy up to 1% at the same CRs, while satisfying HV constraints and keeping complexity under control

Sol-gel synthesis, characterization, and electrochemical evaluation of magnesium aluminate spinel nanoparticles for high-capacity hydrogen storage

In this research, we successfully synthesized magnesium aluminate (MgAl2O4) spinel nanoparticles using a sol-gel process, with stearic acid serving as a capping agent. The synthesis process involved calcination at 900 °C for 4 h, resulting in the formation of nanoparticles with an average crystallite size of approximately 12 nm, as determined through Debye–Scherrer analysis and X-ray diffraction (XRD) data. The optical band gap was measured as 2.84 eV using Diffuse Reflectance Spectroscopy (DRS) analysis. Additionally, we found the mean pore size of the nanoparticles to be 20.2 nm through Brunauer–Emmett–Teller (BET) analysis. We characterized the resulting powders using various techniques, including Fourier Transform Infrared (FTIR) spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Energy-Dispersive X-ray Spectroscopy (EDS), and Vibrating Sample Magnetometry (VSM). We conducted electrochemical investigations utilizing the Chronopotentiometry (CP) technique. The electrochemical analysis demonstrated that MgAl2O4 spinel nanoparticles exhibit a noteworthy hydrogen storage capacity of 4000 mAh/g, highlighting their potential as promising candidates for hydrogen storage applications. This comprehensive study underscores the successful synthesis, thorough characterization, and exceptional electrochemical performance of MgAl2O4 spinel nanoparticles, firmly positioning them as valuable materials for advancing hydrogen storage technologies

Two-dimensional alignment and displacement sensor based on movable broadside-coupled split ring resonators

This paper proposes a two-dimensional alignment and displacement sensor based on movable broadside-coupled split ring resonators (BC-SRRs). As a basis for this sensor, a one-dimensional displacement sensor based on a microstrip line loaded with BC-SRRs is presented firstly. It is shown that compared to previously published displacement sensors, based on SRR-loaded coplanar waveguides, the proposed one-dimensional sensor benefits from a much wider dynamic range. Secondly, it is shown that with modifications in the geometry of the BC-SRRs, the proposed one-dimensional sensor can be modified and extended by adding a second element to create a high-dynamic range two-dimensional displacement sensor. Since the proposed sensors operate based on a split in the resonance frequency, rather than the resonance depth, they benefit from a high immunity to environmental noise. Furthermore, since the sensors' principle of operation is based on the deviation from symmetry, they are more robust to ambient conditions such as changes in the temperature, and thus they can be used as alignment sensors as well. A prototype of the proposed two-dimensional sensor is fabricated and the concept and simulation results are validated through experiment

A magnetically-separable H3PW12O40@Fe3O4/EN-MIL-101 catalyst for the one-pot solventless synthesis of 2H-indazolo[2,1-b] phthalazine-triones

A magnetic inorganic-organic catalyst, PTA@Fe3O4/EN-MIL-101 (EN = ethylenediamine, PTA = phosphotungstic acid) was fabricated and characterized by XRD, HRTEM, FESEM, UV–vis, TGA-DTA, FT-IR, XPS and porosimetry. PTA retained the parent Keggin structure upon dispersion throughout the amine-functionalized chromium terephthalate metal-organic framework, over which magnetic Fe3O4 nanoparticles were previously introduced. The resulting composite heterogeneous solid acid was an active catalyst for the one-pot synthesis of diverse 2H-indazolo[2,1-b] phthalazine-triones in good → excellent yields under mild, solventless condition, and offers facile separation and excellent recyclability

Improved Synthesis of 5-Substituted 1H-Tetrazoles via the [3+2] Cycloaddition of Nitriles and Sodium Azide Catalyzed by Silica Sulfuric Acid

A silica supported sulfuric acid catalyzed [3+2] cycloaddition of nitriles and sodium azide to form 5-substituted 1H-tetrazoles is described. The protocol can provide a series of 5-substituted 1H-tetrazoles using silica sulfuric acid from nitriles and sodium azide in DMF in 72%–95% yield

Homogeneous and heterogeneous catalysts for multicomponent reactions

[EN] Organic synthesis performed through multicomponent reactions is an attractive area of research in organic chemistry. Multicomponent reactions involve more than two starting reagents that couple in an exclusive ordered mode under the same reaction conditions to form a single product which contains the essential parts of the starting materials. Multicomponent reactions are powerful tools in modern drug discovery processes, because they are an important source of molecular diversity, allowing rapid, automated and high throughput generation of organic compounds. This review aims to illustrate progress in a large variety of catalyzed multicomponent reactions performed with acid, base and metal heterogeneous and homogeneous catalysts. Within each type of multicomponent approach, relevant products that can be obtained and their interest for industrial applications are presented.The authors wish to gratefully acknowledge the Generalitat Valenciana for the financial support in the project CONSOLIDER-INGENIO 2010 (CSD2009-00050)Climent Olmedo, MJ.; Corma Canós, A.; Iborra Chornet, S. (2012). Homogeneous and heterogeneous catalysts for multicomponent reactions. RSC Advances. 2(1):16-58. https://doi.org/10.1039/c1ra00807bS16582