Heisenberg’s invention of matrices

Richard Feynman once said: “nobody understands quantum mechanics”. Still, those who devised it are perhaps the ones closest to understanding their creation. It suggests that whenever the weirdness of quantum mechanics haunts you, it is better to go back to its creators in terms of their original publications. In the present article, the author has tried to seek help from Heisenberg’s 1925 paper, in order to reduce the weirdness of going from classical observables to quantum operators.     

The De Kretser case: a note on Sri Lankan writing in English

Abstract

How is the content of a literary canon, or tradition to be configured? What counts as a literary archive? More than 25 years after Edward Said’s Orientalism (1978 Said, W. Edward. 1978. Orientalism, New York: Vintage.  [Google Scholar]), it seems reasonable to assume, that central to such traditions, would be the work of those who live and work in the society that gives rise to it. In this review, such a location of Michele de Kretser’s new novel, The Hamilton Case, is offered, as a caution to metropolitan literary critics who continue to approach Sri Lankan writing in English, as Christopher Columbus approached ‘America’. It is argued that the novel owes much to, and can be read as echoing and elaborating the detective fiction of S.W.R.D. Bandaranaike, who was, also, the fourth Prime Minister of Ceylon (Sri Lanka), 1956–59.     

Screening for lead poisoning in urban school children of southern India using capillary and venous blood samples

Our study aimed at comparing lead and zinc protoporphyrin (ZPP) levels in capillary and venous blood samples in a small population and to employ an easier method of sample collection for a major screening program in school children in major Indian cities. An awareness program on lead and its effects was conducted in two different schools. A total of thirty urban school children from South India, with an age group between 4–12 years consented for dual blood sampling and reported for the study. Venous and capillary blood samples were obtained simultaneously. Blood lead and zinc protoporphyrin (ZPP) levels were estimated using ESA Lead Analyzer and Haematofluorometer respectively. A significant correlation between capillary and venous ZPP (r=0.98) and lead (r=0.99) was observed. Rank sum test showed that there is no statistically significant difference between capillary and venous ZPP (P=0.891) and lead (P=0.672) values. This pilot study recommends that screening for lead may be done using capillary blood samples since significant correlation is observed between capillary and venous blood measurements. Obtaining samples using this mode is a non-invasive, less expensive, quick and easy method in children. Appropriately performed capillary sampling may be considered as an acceptable alternative to venipuncture for screening of blood for lead poisoning both in children and adults.     

Distribution of Methionine Synthase Reductase (MTRR) Gene A66G Polymorphism in Indian Population

Methionine synthase reductase (MTRR) is an important enzyme of the folate/homocysteine pathway. It is responsible for regulation of methionine enzyme by reductive methylation. A common variant A66G is reported in the FMN-binding domain of the MTRR gene, which leads to substitution of isoleucine by methionine (I22M) in MTRR enzyme with reduced activity. Reduced catalytic activity of enzyme leads to high homocysteine concentration in blood and increases risk for numerous diseases. The frequency of A66G polymorphism varies in different ethnic groups. The present study has been designed to evaluate the frequency of MTRR A66G gene polymorphism in the Eastern UP population by PCR–RFLP method. Along with this we also performed a meta-analysis to evaluate the global prevalence of this polymorphism. Databases were screened to identified the eligible studies. The prevalence of the G allele and GG genotype was determined by the use of prevalence proportion with 95% CI. Open meta-analyst software was used for the meta-analysis. Total 1000 blood samples were analyzed, the frequencies of A and G alleles were 0.35 and 0.65 respectively. Meta-analysis results revealed that the prevalence of G allele and GG genotype were 49.4% (95% CI 40.6–58.1, p ≤ 0.001) and 24.3% (95% CI 17.8–30.9, p ≤ 0.001) respectively. In sub-group meta-analysis, the lowest frequency of G allele was found in South America (32.7%; 95% CI 14.1–51.3, p ≤ 0.001), and highest in Asia (56.4%; 95% CI 39.5–73.3, p ≤ 0.001). The results of the meta-analysis showed that the Asian population has the highest frequency of G allele and highest frequency of the GG genotype was found in the European population.     

Comparison of lower body specific resistance training on the hamstring to quadriceps strength ratios in men and women

In this study, we compared hamstring (H) and quadriceps (Q) strength changes in men and women, as well as changes in conventional and functional H:Q ratios following an identical 12-week resistance training program. An isokinetic dynamometer was used to assess 14 male and 14 female participants before and after the intervention, and conventional and functional H:Q ratios were calculated. Hamstring strength improved similarly in men and women, but improvement in quadriceps strength was significantly greater in men, while women showed only modest improvements. For the conventional and functional H:Q ratios, women showed significantly greater improvements than men. Both men and women were able to exceed the commonly recommended 0.6 conventional and 1.0 functional H:Q ratios after the 12-week lower-body resistance training program.     

Young children’s ability to make predictions about novel illnesses

Understanding disease transmission is a complex problem highlighted by the COVID-19 pandemic. These studies test whether 3- to 6-year-old children in the United States use information about social interactions to predict disease transmission. Before and during COVID-19, children predicted illness would spread through close interactions. Older children outperformed younger children with no associations between task performance and pandemic experience. Children did not predict that being hungry or tired would similarly spread through close interactions. Participants include 196 three- to six-year-olds (53% girls, 47% boys; 68% White, 9% Black, 7% Asian, 6% Hispanic or Latinx), with medium-sized effects (d = .6,  = .3). These findings suggest that thinking about social interaction supports young children's predictions about illness, with noted limitations regarding children's real-world avoidance of disease-spreading behaviors.     

Estimation of reference values in liver function test in health plan individuals of an urban south Indian population

Reference intervals in clinical chemistry are commonly based on results of measurements in reference western population or are taken from the western literature. Reference Values are thought to aid physicians to interpret results of measurements and, should be representative of a defined group of individuals. This group should be as similar as possible to the patients under investigation. The reference population in this, study has been recruited from the individuals attending the Health Plan Clinic who fulfill the defined inclusion and exclusion criteria as well as defined partition criteria. The samples were sorted based on the decision by the physician. The emerging group of individuals was considered as a reference population for the hospital patients and the results of measurements in this study was evaluated statistically, to stress on the urgent need to establish the in-house reference values. The reference limits are defined as the central 95 percentile of the population after eliminating the outliers. The lower, reference limit is the 2.5 percentile while the upper reference limit constituted the 97.5 percentile for the population.     

Faecal fat content in healthy adults by the ‘acid steatocrit method’

Malabsorption syndromes causing steatorrhoea are quite common in India. Estimation of faecal fat is an important non-invasive investigation, which provides vital information regarding the occurrence of malabsorption. The aim of this study was to estimate the fat excretion per day in stools of apparently healthy adults on an unrestricted diet in random spot stool samples using the Acid Steatocrit Method, which provides an alternate, simpler and yet reliable method of stool fat estimation. Several studies have proved the correlation of the acid steatocrit method with the conventional methods. In India, however, there has been no published data regarding the normal levels of fat in the stools, by the acid steatocrit method. We follow the normal range values, as set by the United States and the European countries, not having a range for the Indian population. Hence, we took up a preliminary study, to estimate stool fat in a section of normal and healthy Indian population. The result obtained after screening 600 healthy and normal adults, showed the mean of stool fat to be 8.72 gms/24 hours, which is much higher than that, defined by Western literature (7 gms/24 hours). This can be accounted for, by the cultural and ethnic variations in dietary and food habits. Further studies are required in the same direction, involving larger population groups, and in different malabsorptive conditions.