Microwave-assisted synthesis, anticonvulsant activity and quantum mechanical modelling of N-（4-bromo-3-methylphenyl） semicarbazones

Objective： To study the effect of halo substitution on disubstituted aryl semicarbazones on the anticonvulsant potential and model the activity based on quantum mechanics. Methods： A series of twenty-six compounds of N^4-（4-bromo-3-methylphenyl） semicarbazones were synthesized and evaluated for the anticonvulsant activity in the maximal electroshock seizure （MES） and subcutaneous pentylenetetrazole （scPTZ） seizure threshold tests. Some potential compounds were also tested in the subcutaneous strychnine （scSTY） and subcutaneous picrotoxin （scPIC） seizure threshold tests. The synthesized compounds were tested for behavioral impairment and CNS （central nervous system） depression in mice. Quantum mechanical modelling was carried out on these compounds to gain understanding on the structural features essential for activity. Results： Some compounds possessed broad spectrum anticonvulsant activity as indicated by their effect in pentylenetetrazole, strychnine, picrotoxin and maximal electroshock seizures models in resemblance to other aryl semicarbazone derivatives reported earlier. The higher the difference in HOMO （highest occupied molecular orbital） and LUMO （lowest unoccupied molecular orbital） energy levels was, the greater was the activity profile. Conclusion： The pharmacophoric requirements for compounds to exhibit anticonvulsant activity that includes one aryl unit in proximity to a hydrogen donor-acceptor domain and an electron donor have been justified with the molecular orbital surface analysis of the synthesized compounds.     

Journal acquisition—cost effectiveness of models

This paper attempts to compare some of the available models for journal acquisition and indicates their utility in library acquisitions.     

Immunoproteomic analysis of secretory proteins ofAspergillus fumigatus with specific IGE immunoreactivity

Allergenic/antigenic proteins are known to induce Type I and Type III hypersensitivity reactions leading to allergic bronchopulmonary aspergillosis (ABPA) in immunocompetent host. The common structural features or intrinsic properties of the allergens/antigens leading to allergenicity in a host are not well understood. In the current report, comparative analysis of proteins on two dimensional gel electrophoresis (2D-3) and specific IgE immunoblots ofA. fumigatus secretory proteins (1^st, 2^nd and 3^rd week culture filtrate proteins) was carried out. We observed a total of 159 proteins in 1^st, 2^nd and 3^rd week culture filtrates ofA. fumigatus. Specific IgE immunoreactivity was observed in 75 proteins with different intensity. Third week culture filtrate showed maximum number of proteins, 142, and specific IgE immunoreactive proteins, 65. MALDI-TOF analysis resulted in putative identification of two allergens as hypothetical protein YBL057c fromSaccharomyces cereviseae and unnamed protein product fromDebaryomyces hansenii (similar to IPF14568 ofCandida albicans). Identification of a repertoire of specific IgE immunoreactive proteins will facilitate the studies on structure-function relationship of these proteins relevant for diagnosis and pathogenesis.     

Futility1 of Log‐Linear Smoothing when Equating with Unrepresentative Small Samples

The impact of log‐linear presmoothing on the accuracy of small sample chained equipercentile equating was evaluated under two conditions . In the first condition the small samples differed randomly in ability from the target population. In the second condition the small samples were systematically different from the target population. Results showed that equating with small samples (e.g., N < 25 or 50) using either raw or smoothed score distributions led to considerable large random equating error (although smoothing reduced random equating error). Moreover, when the small samples were not representative of the target population, the amount of equating bias also was quite large. It is concluded that although presmoothing can reduce random equating error, it is not likely to reduce equating bias caused by using an unrepresentative sample. Other alternatives to the small sample equating problem (e.g., the SiGNET design) which focus more on improving data collection are discussed.     

Are we using Thyroid Function Tests Appropriately?

Thyroid function tests are very important for the diagnosis and monitoring of patients with thyroid dysfunction. The guidelines recommend serum thyroid stimulating hormone (TSH) as the single most reliable test to diagnose all common forms of hypothyroidism and hyperthyroidism. The aim of this study was to analyze the ordering pattern for thyroid function tests by physicians and the analysis of results based on the clinical history. The mean age of the patients was 32.5 ± 6.5 years. Majority of samples (87.7% of total) were received from the departments of Medicine and Gynae. Thyroid profiles (47.5%) were ordered more frequently as compared to TSH only (46%). There was no significant difference in the percentage of normal reports for both types of tests. 77.8% of TFT and 76.6% of TSH samples had results within the reference range. The percentage of abnormal results was 13.7% in the patients who were screened for thyroid disorders. There is a need to redefine the case definition for thyroid dysfunction and order the appropriate test in a rational and cost effective manner.     

Analyzing the temporal evolution of students’ behaviors in open-ended learning environments

Metacognition and self-regulation are important for developing effective learning in the classroom and beyond, but novice learners often lack effective metacognitive and self-regulatory skills. However, researchers have demonstrated that metacognitive processes can be developed through practice and appropriate scaffolding. Betty’s Brain, an open-ended computer-based learning environment, helps students practice their cognitive skills and develop related metacognitive strategies as they learn science topics. In this paper, we analyze students’ activity sequences in a study that compared different categories of adaptive scaffolding in Betty’s Brain. The analysis techniques for measuring students’ cognitive and metacognitive processes extend our previous work on using sequence mining methods to discover students’ frequently-used behavior patterns by (i) developing a systematic approach for interpreting derived behavior patterns using a cognitive/metacognitive task model and (ii) analyzing the evolution of students’ frequent behavior patterns over time. Our results show that it is possible to identify students’ learning behaviors and analyze their evolution as they work in the Betty’s Brain environment. Further, the results illustrate that changes in student behavior were generally consistent with the scaffolding provided, suggesting that these metacognitive strategies can be taught to middle school students in computer-based learning environments.     

Oxidative Stress-Induced Response of Some Endogenous Antioxidants in Schizophrenia

Reactive oxygen species (ROS) formed in various metabolic reactions cause unlimited damage by attacking and oxidizing the macromolecules. An arsenal of antioxidant substances neutralizes these ROS at various sites of their metabolic cascade, and if disequilibrium exists between the pro and antioxidant system, oxidative stress persists. The present study was undertaken in schizophrenia, to highlight the response and role of some endogenous antioxidants viz. reduced glutathione (GSH), bilirubin, total proteins, albumin and uric acid in scavenging the ROS. The effect of severity of disease, age factor, and substance abuse was also studied. In all, 50 schizophrenics and 50 age and sex-matched controls were enrolled in the present study. Fasting blood samples were drawn for estimating malondialdehyde (MDA), GSH, bilirubin, total proteins, albumin and uric acid in both the groups. The results were statistically analyzed by Z-test and correlated using correlation coefficient (r). The study shows reduction in MDA levels and decline in the level of endogenous antioxidants, but within the normal range. Chronic schizophrenics were at a higher risk of oxidative stress and age and substance abuse seems to worsen the situation.     

Value for learning during this time of transformation: the first-year students’ perspective

ABSTRACT

Formal education was used by the apartheid government to prepare black South Africans for manual labour, thus there was little curricular focus on the development of higher-order cognitive skills. With the abolition of apartheid in 1994, the education system was re-valued and re-evaluated to provide wider access to quality education; the focus of education policies moved towards the development of self-regulation and higher-order cognitive skills for all learners. There is now a generation of learners who have experienced their schooling in the transformed education system, and it would be useful to understand, from their perspective, what they value in their development of learning within the higher education space. This study answers the question ‘Post-apartheid, what learning methods and resources do first-years perceive to be valuable to their learning when they enter university?’ Participants included 344 students taking a Biology course provided to medical science students at a South African university in 2018. Two questionnaires were administered towards the end of a six-week lecture period, responses were evaluated quantitatively and qualitatively. The first survey, comprised of Likert-style questions, was conducted to determine the students’ views on the mechanisms which they used to support their learning. The second questionnaire comprised open-ended questions and focused on the students’ perception of their learning experience in the course. The findings show that there was a significant (p?<?.001) percentage of first-years who thought that rote-learning would suffice for examination preparation at university, and preferred to engage with their peers and the textbook before they engaged with their lecturers when navigating challenging concepts. Schwartz's model of social values is used to show that more needs to be done for the development of higher-order thinking and self-regulation when students enter university, and to mitigate alienation between students and staff.     

Oxidative stress, α-tocopherol, ascorbic acid and reduced glutathione status in schizophrenics

A disturbance in the antioxidant defense system including α-tocopherol, ascorbic acid and reduced glutahtione metabolism due to free radical induced oxidative injury has been implicated in various neuro-psychiatric disorders. The roles of these antioxidants, changes in their blood levels and correlation with oxidative stress were studied in a common psychiatric illness Schizophrenia. Fifty-eight subjects of either sex ranging in age from 18–60 years divided into two age groups (≤40 and >40 years) diagnosed for schizophrenia, and forty age and sex-matched normal subjects as controls were included in the study. Blood samples were analyzed for malondialdehyde (MDA), α-tocopherol, total ascorbic acid (TAA), dehydro ascorbic acid (DHAA), reduced ascorbic acid (RAA), leucocyte ascorbic acid (LAA) and reduced glutathione (GSH). A decrease in the levels of α-tocopherol, total ascorbic acid and reduced glutathione was found in schizophrenics compared to normal controls. Further a significant rise in oxidative stress and decreased antioxidant status was observed in the chronic stage of schizophrenia as compared to those in acute condition. A significant rise in dehydroascorbic acid with concomitant fall in reduced ascorbic acid suggests scavenging action of ascorbic acid and its utilization with increased oxidative stress as indicated by high blood malondialdehyde levels. Leucocyte ascorbic acid, a better index of ascorbic acid status was also found to be reduced in schizophrenics, suggesting depletion of body stores of ascorbic acid and the condition worsened with advancing age.     

Missing in Measurement: Why Identifying Learning in Integrated Domains Is So Hard

Journal of Science Education and Technology - Integrating computational thinking (CT) and science education is complex, and assessing the resulting learning gains even more so. Arguments that...