#অপরিচিতবাঙালিবিজ্ঞানীরা
By: Krishna Halder
- Amal Kumar Raychawdhuri (Singularity Theorem):
He was a theoretical physicist, did his research in the field of cosmology and general relativity, studied in Presidency college and Science College (Calcutta University).
He derived a fundamental equation which helped Stephen Hawking and Roger Penrose in their attempt to answer the question on the existence of space-time singularities and to explain the theory of universe.
The equation was termed as ‘Raychaudhuri Equation’ with its first appearance in a research paper published in 1965 by George F.R. Ellis and Stephen Hawking.
Becoming a key ingredient in the proofs of the Penrose–Hawking singularity theorems the Raychaudhuri equation paved the way for later research into the singularity problem. His 1955 paper was highly regarded by notable physicist Pascual Jordan.
Also, the work done by him got a special appreciation from Prof John Archibald Wheeler. In general relativity, the Raychaudhuri equation plays a significant role to explain the space-time singularities and gravitational focusing properties in cosmology.
2. Sambhu Nath De (Cholera Toxin):
He was a medical scientist and researcher, studied in Calcutta Medical College and completed Diploma in Tropical Medicine and did his Ph.D. from University College Hospital Medical School, London.
He discovered the cholera toxin in 1959.
He worked on pathogenesis of cholera and related diarrhoeal diseases and set a permanent milestone in the modern view of diseases caused by bacterial exotoxins. He was the first to demonstrate that cholera bacteria secrete enterotoxin.
This discovery eventually promoted research to find a treatment aimed directly at neutralising the cholera enterotoxin. As noted by John Craig, De’s work was truly creative and novel, and it “forever altered our concepts surrounding the pathogenesis of secretory diarrhoea.”
Biochemist W.E. van Heyningen and John R. Seal note that De’s paper “deserves to go down as a classic in the history of cholera, and, indeed, as later developments have shown, in the history of cellular physiology and biochemistry.”
His findings on exotoxins helped in the purification of cholera and heat-labile enterotoxins produced by V. cholerae and E. coli,respectively, and in the development of series of cholera and ETEC vaccines.
These famous findings came out from the work he carried out at the Nilratan Sircar Medical College, Calcutta Medical College and Bose Institute, Kolkata. Nobel laureate Prof. Joshua Lederberg had nominated De for the Nobel Prize more than once.
3. Dr. Subhash Mukhopadhyay (Test Tube Baby):
He was an extraordinary Indian Physician and Researcher, studied in University of Calcutta and Calcutta National Medical College. He did his first Ph.D. from Rajabazar Science college and second Ph.D. from University of Edinburgh.
He became the first physician in India (and second in the world after British physicians Patrick Steptoe and Robert Edwards) to perform the in vitro fertilisation resulting in a test tube baby “Durga” (alias Kanupriya Agarwal) on 3 October 1978.
Due to the novelty of Dr. Mukhopadhyay’s work, currently his method is globally followed. His process was highly impactful and widely accepted by the scientific world.
Also, at the University of Edinburgh, he did an extraordinary work on hormones. Title of his thesis was, “Some Observations on The Biological Assay of Gonadotropic Hormones”.
Before him, there was no great way to detect the levels of this hormone, but his remarkable work in this field opened many avenues.
4. Gopal Chandra Bhattacharya (life of plants & insects):
He was an eminent entomologist, naturalist and science writer. Coming from a poor family and having no formal degree in higher education, he published his first research paper in 1932, on life events in the body of plants.
Subsequently, he also published work on bioluminescence and other botany topics, but gradually his interests shifted to entomology. He became an expert photographer, and photographed many varieties of ants, spiders, small bats and tadpoles.He joined Bose Institute in the year 1921 as Research Assistant under Prof. Jagadish Chandra Bose. In total, he published 22 papers in English. He wrote about fourteen books and 800 articles in different popular science and other journals in Bengali.In 1943, he published an article in the Transactions of the Bose Institute of Calcutta, “Reproduction and caste determination in aggressive red ants, Oecophylla smaragdina” outlining how the queen in social insects such as ants or bees, produces other queens, workers or soldiers.In 1948, he worked with Satyendra Nath Bose to establish the Bangiya Bijnan Parishad (Bengal Science Council).
In 1981, the University of Calcutta awarded him an honorary Doctor of Science degree less than three months before he died.
5. Nilratan Dhar (atmospheric nitrogen fixation):
He was a chemist and specialist in Soil Science. He studied in Presidency College, Calcutta University, obtained his DSc degree from London University, and the State Doctorate of Science degree from the Sorbonne University, Paris.
He is considered as the “Father of Indian Physical Chemistry.” He discovered the process of thermal and photo-chemical fixation of atmospheric nitrogen in the soil. He was a visiting lecturer in many European Colleges and Universities.He carried out many researches and worked in different european laboratories. He suggested a simple method of improving alkali soils by the application of molasses, press-mud and other organic materials to such soil.He carried on independent research work on double and complex salts, combination of solute and solvent and published these papers in Germany. Moreover, chemical kinetics, photochemistry and colloid chemistry were developed by Dhar and his collaborators.He also determined the EMF of various systems and published his research articles in prestigious journals.
Acharya Ray, in his autobiography, very graciously recorded that NR Dhar was certainly the founder of physical chemistry and physico-chemical researches in India.
Credit: Wikipedia
