Association between relative age effect and organisational practices of American youth football

The popular method of organising youth sport participants into age divisions, based solely on their birthdate, can result in an imbalance of the distribution of players. This is known as relative age effect (RAE), which inadvertently creates bias and is associated with deleterious short and long-term consequences. The overall purpose of this study was to examine how the potential for RAE is mitigated when simultaneously accounting for additional player criterion, supplementary to age. A mid-Atlantic American youth football registration database was acquired, including chronological (age), anthropometric (weight), and competency (skill) factors. Player (n = 1,265) data were classified into quartiles and multiple chi-square goodness of fit tests were conducted using proportions of live births as expected theoretical distribution values. When data were categorised by a single developmental criterion (e.g. age), results indicated significant departures (p ≤ 0.002) from expected proportions. However, when categorised using multiple criteria (i.e. age, weight, and skill), equitable birthdate distributions were observed. Findings from this study indicate using only one developmental criterion for organising players is associated with RAE, whereas approaches accounting for multiple variables are not associated with RAE. This study provides youth football programs with early evidence for considering alternative methods of organising players.     

Effects of Transparency and At-Stakeness on Students' Perceptions of Their Ability to Work Collaboratively in Effective Classroom Teams: A Partial Test of the Jassawalla and Sashittal Model

While teams are common in business school classrooms, scholars note that few instructors provide teamwork-related instruction. The consequent negative experiences may explain the reported cynicism about teamwork among students. This article reports findings from a study that examined the link between a teaching strategy designed to help students function more effectively in teams and its impact on student perceptions of their ability to work collaboratively with others and on their perceptions of their team's effectiveness. The study found evidence to suggest that a teaching strategy designed to help students reach the multiple stages of team development such as high levels of at-stakeness and transparency positively impacts their perceptions and that these stages effectively mediate the link between the strategy and key outcomes.     

Knowledge, attitude, and practices regarding whole body donation among medical professionals in a hospital in India

Voluntary body donation has become an important source of cadavers for anatomical study and education. The objective of this study was to assess knowledge, attitude, and practice (KAP) regarding whole body donation among medical professionals in a medical institute in India. A cross sectional study was conducted at Kasturba Hospital, Manipal, India, among medical doctors. Data was collected from consenting individuals in the age group of 25-65 years by convenience sampling method. A semi-structured, pretested, questionnaire designed to assess KAP regarding whole body donation was provided to the study population (n = 106); 97 individuals returned the completed questionnaire. Results showed that 8% of the medical professionals were unaware of the term body donation and 85% believed that donated bodies were misused. A large proportion of the respondents did not know about the authority that oversaw body donation, or its criteria for accepting donated bodies and diseases for which bodies were screened before acceptance. Only 22% of polled physicians were willing to donate their bodies for medical education, but 68% expected the public to do the same. While only 7% had already registered their own names for body donation, 64% were not aware of any known person having registered and 72% indicated that their decision would not be influenced even if they knew of friends who had registered. These results suggest that educating medical students and professionals regarding the altruistic act of body donation is as important as educating the general public.     

Quantization of the radiation field

I briefly review the seminal 1927 paper of Dirac which emphasized the need for the quantization of the electromagnetic field and then showed how to carry it out. After mentioning few historical developments, I then point out some of the outstanding successes of quantum electrodynamics —the kind of agreement which exists between theory and experiment is unprecedented in the history of science. Avinash Khare is with the Institute of Physics, Bhubaneswar. His main interests are in the areas of field theory, nonlinear physics, anyons and supersymmetric quantum mechanics.     

Untangling the mystery of Alzheimer’s disease

Alzheimer’s disease is one of the most common neurodegenerative disorders amongst the elderly, leading to dementia. Current studies of its molecular basis reveal various factors culminating in the cytotoxic cascade associated with the disease. Progress in understanding these events has led to the identification of novel therapeutic targets. This article is an attempt to understand the global scientific efforts in deciphering the mystery of this disease for a possible cure. All are postgraduate students at School of Biotechnology, Madurai Kamaraj University, Madurai. Sovan Sarkar’s research interests are gene therapy, apoptosis in cancer treatment and therapeutic approaches for neurodegenerative disorders. Anupam Choudhury is interested in the study of cytoskeleton and motor proteins, specifically kinesins. T N Avinash is deeply interested in neuroscience, especially in learning and memory.     

Vulcanization of rubber

The chemical modifications that occur during vulcanization of rubber and methods for controlling the process are discussed.