An Automated Item Pool Assembly Framework for Maximizing Item Utilization for CAT

Computerized adaptive testing (CAT) has gained deserved popularity in the administration of educational and professional assessments, but continues to face test security challenges. To ensure sustained quality assurance and testing integrity, it is imperative to establish and maintain multiple stable item pools that are consistent in terms of psychometric characteristics and content specifications. This study introduces the Honeycomb Pool Assembly (HPA) framework, an innovative solution for the construction of multiple parallel item pools for CAT that maximizes item utilization in the item bank. The HPA framework comprises two stages—cell assembly and pool assembly—and uses a mixed integer programming modeling approach. An empirical study demonstrated HPA's effectiveness in creating a large number of parallel pools using a real-world high-stakes CAT assessment item bank. The HPA framework offers several advantages, including (a) simultaneous creation of multiple parallel pools, (b) simplification of item pool maintenance, and (c) flexibility in establishing statistical and operational constraints. Moreover, it can help testing organizations efficiently manage and monitor the health of their item banks. Thus, the HPA framework is expected to be a valuable tool for testing professionals and organizations to address test security challenges and maintain the integrity of high-stakes CAT assessments.     

Subordination and superordination properties of multivalent functions defined by certain integral operator

For normalized multivalent functions, we study different applications of the theory of differential subordination and superordination, that are connected to a recent linear operator defined by Liu and Owa.     

Bifurcation analysis of a microcantilever in AFM system

The atomic force microscope system (AFM) has become a popular and useful instrument to measure the intermolecular forces with atomic resolution that can be applied in electronics, biological analysis, materials, semiconductors, etc. This paper studies the bifurcation phenomenon and complex nonlinear dynamic behavior of the probe tip between the sample and microcantilever of an atomic force microscope using the differential transformation method. The dynamic behavior of the probe tip is characterized with reference to bifurcation diagrams, phase portraits, power spectra, Poincaré maps, and maximum Lyapunov exponent plots produced using the time-series data obtained from differential transformation method. The results indicate that the probe tip behavior is significantly dependent on the magnitude of the vibrational amplitude. Specifically, the probe tip motion changes from T-periodic to 3T-periodic, then from 6T-periodic to multi-periodic, and finally to chaotic motion with windows of periodic motion as the vibrational amplitude is increased from 0 to 5.0. Furthermore, it is demonstrated that the differential transformation method is in good agreement for the considered system.     

Three Cases of Lead Toxicity Associated with Consumption of Ayurvedic Medicines

Ayurveda is a traditional form of medicine used by majority of the Indians. Here we report three cases of lead toxicity, following intake of Ayurvedic medicines. Three patients presented with blood lead levels (BLLs) of 122.4, 115 and 42.8 μg/dl respectively at the time of hospitalization. The first case was chelated with D- penicillamine, the second with calcium disodium ethylene diamino tetra acetate (EDTA) and the third with environmental intervention and education. Associated Ayurvedic products were collected from patients and analyzed for metallic concentration. Cessation of Ayurvedic medication along with chelation, nutritional intervention and education, reduced the BLL to 27.4 μg/dl in the first case after 1 year, 21.1 μg/dl after 9 months in the second and 18.2 μg/dl after 6 months in the third case.     

Biochemical and genetic studies on cardiometabolic syndrome

Cardiometabolic syndrome is one of the major public health issues of this century which describes a cluster of clinical characteristics. Seventy two patients with coronary artery disease (CAD) and cardiometabolic syndrome and forty healthy age and sex matched normal controls were selected for this study. Detailed clinical epidemiological and anthropometric characteristics were noted. Lipid profile and Cytokinesis-block micronuclei (CBMN) assay using cytochalasin B were carried out in all the subjects. Serum total cholesterol, triglyceride and LDL-cholesterol was significantly higher and HDL cholesterol was significantly lower in patients compared to their normal counter-parts (P<0.05). CBMN frequency of the patients was significantly higher at all ages compared to their normal counter parts (P<0.05). Various risk factors like diabetes, hypertension, dyslipidemia, abdominal obesity, smoking and alcoholism were found influenced the CBMN frequency; but the changes were not significant. From this study it can be concluded that DNA damage was found to be higher in patients with cardiometabolic syndrome which may be attributed to the generation of free radicals associated with alcohol consumption, tobacco use, dyslipidemia and glucose intolerance and the accumulation of free radicals with increase in age.     

Self-modeling as an intervention to increase student classroom participation

The effect of self-modeling as an intervention to increase individual participatory behavior in the classroom was investigated using a multiple baseline design across three second grade students with a follow-up. In addition, a control student was employed to further investigate the effects of the intervention. Self-modeling is defined as the positive change in behavior resulting from spaced viewing of oneself on edited tapes depicting exemplary behavior. Students viewed edited videotapes of themselves successfully volunteering to participate in class by raising their hand. The three students, during baseline, had a mean participation rate ranging between 8% and 24% compared with the control student's rate ranging between 53% and 63%. During intervention, the mean participation rate ranged between 28% and 60% compared with the control student's rate ranging between 43% and 46%. At follow-up, students had a mean percentage rate ranging between 44% and 64% compared with the control student's rate of 53%. Thus, they more closely approximated or surpassed the control student's mean rate of participation during intervention and follow-up, suggesting that the self-modeling intervention was effective in increasing individual participatory behavior in the classroom. © 1998 John Wiley & Sons, Inc.     

Index of science reading awareness: An interactive-constructive model,test verification,and grades 4–8 results

The purpose of this study was to develop and verify the Index of Science Reading Awareness (ISRA) based on a model of an efficient, successful interactive-constructive science reader and three independent metacognitive awareness domains. Several researchers have noted the need for efficient, reliable, and valid measures of metacognition. ISRA data collected on 532 students (Grades 4–8) were analyzed using factor analyses, linear structural modeling, and analyses of variance (ANOVAs) to help verify the model and the test. The factor analyses and linear structural modeling indicated that these data did not support the assumption about the three independent metacognitive awareness domains, but suggested that the model and the test were structured around the design features of science reading, science text, and science reading strategies. One-way ANOVAs indicated significant, predicted reading ability and gender differences but unexpected grade-level differences. The composite metacognitive awareness data indicated that most Grade 4–8 students have surface knowledge about science reading, science text, and science reading strategies, and indicated specific targets for explicit science reading instruction. © 1998 John Wiley & Sons, Inc. J Res Sci Teach 35: 27-51, 1998.