AC susceptibility study of superconducting YBa2Cu3O7:Agx bulk composites (x = 0.0-0.20): The role of intra and inter granular coupling

We report the effect of silver addition on superconducting performance of bulk YBCO (YBa2Cu3O7) superconductor. All the studied samples are prepared by conventional solid-state reaction method. Rietveld fitted X-ray diffraction data confirmed the single phase formation for all the studied samples. Detailed AC susceptibility measurements as a function of driven AC amplitude (1Oe-17Oe) of these samples revealed the enhancement of grains coupling with increasing Ag content in YBCO+Agx composite system. 10wt% Ag added YBCO superconductors exhibited the optimum inter granular coupling. The Scanning Electron Microscopy (SEM) observations indicate an increase in the grains connectivity in terms of narrow grain boundaries for doped samples. The average grain size is found to increase with Ag doping. It is concluded that limited addition of Ag in bulk YBCO superconductor significantly improves the grains coupling and as result optimum superconducting performance. YBCO+Ag composites could prove to be potential candidates for bulk superconducting applications of the studied high Tc system.Comment: 15 pages of text + Fig

Evolution of superconductivity in PrFe1-xCoxAsO with x = 0.0 to 1.0

We report the synthesis and physical property characterization of PrFe1-xCoxAsO with x = 0.0 to 1.0. The studied samples are synthesized by solid state reaction route via vacuum encapsulation method. The pristine compound PrFeAsO does not show superconductivity, but rather exhibits a metallic step like transition due to spin density wave ordering of Fe moments below 150 K, followed by another upward step due to anomalous ordering of Pr moments at 12 K. Both the Fe-SDW and Pr-TN temperatures decrease monotonically with Co substitution at Fe site. Superconductivity appears in a narrow range of x from 0.07 to 0.25 with maximum Tc at 11.12 K for x = 0.15. Samples, with x = 0.25 exhibit metallic behavior right from 300 K down to 2 K, without any Fe-SDW or Pr-TN steps in resistivity. In fact, though Fe-SDW decreases monotonically, the Pr-TN is disappeared even with x = 0.02. The magneto transport measurements below 14 Tesla on superconducting polycrystalline Co doped PrFeAsO lead to extrapolated values of the upper critical fields [Hc2(0)] of up to 60 Tesla.Comment: 15 pages Text+Fig

Human elements from an anthropological point of view

During the time when the human race lived nomadically without a place, Man was given grammar and the lord of nanilam was Thamizhan. Sangam literary songs are an immovable historical trace of society, which is an experiential experience of Tamils who have touched the top of happiness by treating life as a boon. In Tamil Nadu, ethnic groups are discriminated against on the basis of dinas. This discrimination is in line with anthropological interpretation. Both birth and death were considered sacred in the tribal society. They realized the changes in nature and changed their lives accordingly. Changes are considered to be the stages and steps of the development of the ethnic society. As the tribals of Tamil Nadu merged with the other classes, many cultural elements developed in their lives. Human origin, ethnic identities, primary divisions of anthropology, Tamil origin, speciality of human species, status of tribes in India etc. are explained

The Importance of Surprise in Mathematical Beauty

Mathematicians, mathematics education researchers, and philosophers have written about mathematical beauty and many of the qualities commonly associated with it, such as simplicity, brevity, enlightenment, etc. One key theme that underlies many of these qualities is surprise or the unexpected. In this article, I discuss the integral role surprise plays in mathematical beauty. Through examples, I argue that simplicity alone is oftentimes not enough for a piece of mathematics to be considered beautiful, but rather it is unexpected simplicity that we seek. I propose, moreover, that surprise is necessary for enlightenment. The paper also reports results from an activity designed to elicit an appreciation of mathematical beauty from elementary preservice teachers; the majority reaction was a feeling of surprise. Understanding the relevance of surprise to mathematical beauty may offer us a feasible way to create opportunities for students to experience mathematical beauty

A Case of Misalignment of Reasoning, Affect, and Performance in the Transition-to-Proof

Learning how to prove is known to be difficult for undergraduate students. Understanding students’ growth in the multiple arenas that make up proving is crucial for supporting them. Across four interviews over a semester, I examine one student who showed growth in his reasoning but whose proofs were still incorrect, yet he showed high levels of positive affect including confidence throughout. Investigating this single-subject case serves as an example of the interplay between development and performance. The question of whether we can say this student is a better prover than before––fundamentally, how to weigh reasoning versus affect versus performance––motivates the need for robust frameworks to characterize a student’s progress in proving

Online learning during COVID-19 pandemic - a cross sectional survey of students’ perception

Background: The corona virus pandemic had an impact on the student’s education especially the medical and dental students. There was no option but to continue the education by using the online platforms to take lectures. This survey aims at finding out the students’ perception towards these online classes.Methods: After ethics committee approval, a pre-validated questionnaire was administered as a Google form to the first, second bachelor of medicine and bachelor of surgery (MBBS) students and first, second bachelor of dental surgery (BDS) students, data was analyzed using descriptive statistics in Microsoft excel.Results: Out of 400 students who were sent the questionnaire 169 answered, with a response rate of 42.25%. 43 (25.44%) students had responded that the availability of the PowerPoint presentation for future reference makes it better for their study. 59 (34.91%) students said the main problem with the online lectures was Internet connectivity and technical issues /buffering during the class. Mean was 3 and above for three questions regarding the interaction during online classes and missing face to face interaction with both faculty and students.Conclusions: There is a positive attitude towards online learning, but the students miss the face-to-face interaction with the faculty and students. There is a necessity for improving the required infrastructure as well as training the faculty for the use of online platforms for planning and undertaking the sessions in an interactive way keeping in view the future occurrence of similar situations

IMPORTANCE OF NUTRITION ASSESSMENT IN CRITICALLY ILL PATIENTS

A timely assessment of nutritional status in critically ill patients is crucial. This was an observational prospective hospital study carried out for 3 months from December 2019 to February 2020 in an ICU in a multispecialty hospital in Madurai, Tamilnadu, India. All adult patients with ≥ 72 hours of ICU-LOS were included and their nutritional assessment was completed by SGA (Subjective Global Assessment) forms within 24 hours of ICU admission. Data collected regarding variables such as Age, Nutritional status, APACHE IV, SOFA score, presence of Comorbidities. All patients were studied about their duration of stay in ICU and hospital, Predicted Mortality rate, & discharge outcome.120 patients were involved in the study in the age 62. 2 ± 14.years, among this 55.3% were males and rest 44.7% were females. Their complete nutritional assessment revealed that 50%, 43%, and 17% were well nourished, moderately malnourished, severely malnourished respectively. A strong correlation was observed between nutritional status, morbidity, and their prolonged stay in ICU. Mean ICU & hospital mortality percentage was 37%, 45% respectively. The average duration of stay in the ICU and hospital was 13, 20 days respectively. Participants anthropometric data decreased considerably (mean weight, MUAC, calf circumference) during ICU discharge day. BMI comparison of admission and discharge didn’t show significant change. Timely nutrition intervention and medical nutrition therapy reduce the duration of patient stay in ICU and hospital and improved patient outcomes. The disease severity scoring system can be used as guidance for objective assessment of disease outcomes and estimation of the chance of recovery

VARIATION OF PEAK EXPIRATORY FLOW RATE WITH BODY MASS INDEX IN THE FIRST YEAR MALE MEDICAL STUDENTS OF VISWABHARATHI MEDICAL COLLEGE, KURNOOL

Background: Obesity has become one of the major health issues in India. WHO defines obesity as “A condition with excessive fat accumulation in the body to the extent that the health and wellbeing are adversely affectedâ€. Obesity results from a complex interaction of genetic, behavioral, environmental and socioeconomic factors causing an imbalance in energy production and expenditure. Peak expiratory flow rate is the maximum rate of airflow that can be generated during forced expiratory maneuver starting from total lung capacity. The simplicity of the method is its main advantage. It is measured by using a standard Wright Peak Flow Meter or mini Wright Meter. The pulmonary disorders due to obesity results in increased mortality and morbidity. Aims: To study the effect of Body Mass Index on Peak Expiratory Flow Rate in Medical students. Methods & Methods: study was performed on 60 Male age group of 17-22 Years, categorized as normal Weight BMI= 18.5-24.99kg/m2 and overweight BMI= 25-29.99 Kg/m2. There were 30 students with normal Weight BMI and 30 students with overweight BMI. Normal weight BMI subjects acted as control group to compare the Peak Expiratory Flow Rate with over weight. The parameters studied were weight, height, age, body mass index and Peak expiratory flow rate (PEFR). Student’s unpaired t-test was used for two group’s comparison. Results: The results of the investigation revealed a significantly lower Peak expiratory flow rate (PEFR) among the overweight BMI subjects compared to normal weight BMI subjects. Conclusion: Thus it is evident from the present study that obesity significantly affects the pulmonary functions which may give rise to long term complications and may lead to early morbidity and mortality.Key words: Peak Expiratory Flow Rate; Body Mass Index; Obesity

Microsatellite (SSR) markers assisted characterization of rice (Oryza sativa L.) genotypes in relation to salt tolerance

151-163Under present investigation a total of 18 rice genotypes with diverse genetic background were taken for screening at seedling stage and its molecular characterization using SSR markers. Selected rice genotypes were exposed to five salinity levels (0, 2, 4, 6 and 8 dSm-1) at seedling stage. Modified standard evaluation score (SES) at seedling stage identified 7 highly tolerant, 2 tolerant and 8 moderately tolerant genotypes. The susceptible genotype was IR64 with score 7. Considering 4 other morpho-physiological characters (germination percent, K/Na ratio, shoot and root length, shoot and root fresh weight, shoot and root dry weight) studied at seedling stage, the genotype CSR2K-262 showed greater tolerance among all the 18 genotypes. For molecular characterization a total of 44 SSR markers were selected. The average number of alleles per locus was 9.3 indicating greater magnitude of diversity among plant materials. The average PIC value 0.767 confirmed that the markers used were highly informative. The cluster analysis grouped the 18 genotypes into three major clusters. Cluster I was the largest with 9 genotypes with all highly tolerant and tolerant genotypes, Cluster II comprised 8 genotypes with all tolerant and moderately tolerant and Cluster III comprised of 1 genotype (IR64) identified as susceptible one