4,646 research outputs found
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
A cost variation analysis study of various bisphosphonates preparations available in the Indian market
Background: Osteoporosis is a chronic disease leading to weakened and porous bones which increases the risk of fractures. It is a treatable condition using drugs like bisphosphonates. There is wide variation in the cost among various brands of bisphosphonates in the Indian market, so the objective of the study was to analyse cost of different brands of bisphosphonates.Methods: Cost of both oral and injectable bisphosphonates in the same strength and dosage forms was obtained from CIMS India (January-April 2019). For oral form of the drug, price was calculated per 10 tablets, for injectable form the price per ampoule or vial was calculated and cost ratio, percentage of cost variation was calculated.Results: 15 different formulations of bisphosphonates were analyzed and it was found that cost ratio is found to be highest with 60 mg of pamidronate injection and lowest with 10 mg alendronate tablet, also pamidronate 60 mg injection has highest percentage of cost variation (9632%) and lowest cost variation is seen with 10 mg alendronate (35%). Cost ratio of 11 formulations was found to be very high which was >2 while percentage of cost variation of 11 formulations was found to be more 100.Conclusions: This study concludes that there is wide variation in cost of various brands of bisphosphonates in India. The huge price variation creates unnecessary burden leading on the patients resulting in noncompliance which increases the risk of morbidity and mortality. Therefore, there is an urgent need to regulate the cost of various formulations of bisphosphonates which will reduce the financial burden on the patients
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