Browsing by Author "Begum, Mahbuba"

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Ecology, Biology and Fishery of Clupisoma Atherinoides (Bloch) (Cypriniformes:Schilbeidae)Ecology, Biology and Fishery of Clupisoma Atherinoides (Bloch) (Cypriniformes:Schilbeidae)
(University of Rajshahi, 1999) Begum, Mahbuba; Bhuiyan, M. Abdus Salam
The juvenile and adult of C. atherinoides is mainly a carnivorous fish. Its food consists mainly of crustaceans, insects, rotifers, protozoans, algae, debris and detritus. The juvenile and adult C. atherinoides are surface feeders. Monthly variations in the percentage composition of the food items in the different stages of the fish were recorded. The fish changed its food and feeding habit seasonally. The feeding intensity was very poor in mature fishes during the spawning period. The immature fishes fed actively throughout the year. The ratio of the total length and alimentary canal length of the juvenile and adult stages of the fish is I :0.56 and 1: O. 61 and it has a shortened alimentary tract. The relationships between the total length and alimentary canal length of the juvenile and adult showed strong linear relationship. The ovaries of C. atherinoides were classified into ten stages. Immature stage, maturing-I ( early developing), maturing-II (late developing), mature, ripe, pre-spawning, spawning, post spawning, spent and resting stage.----
Elemental Identification and Radiological Characterization of Core and Surface Samples for Environmental Assessment in Gas Field Regions of Bangladesh
(©University of Dhaka, 2023-06-13) Begum, Mahbuba
In the oil and gas production industries all over the world, produced water contain the largest portion of wastes and the second largest portion of wastes is drilling waste, both of which are dumped into the evaporation pond and so the pond is assumed to be the main deposit of higher level of toxic element wastes and naturally occurring radioactive materials (NORMs). In Bangladesh, this contaminated water mostly in rainy season, over-flooded and spread to the nearby environment and resulting soil contamination. The yearly produced water deposition of Shabazpur gas field, Saldanadi gas field and Fenchuganj gas field are 27,53,244 L, 2,26,499 L and 28,13,944 L respectively, along with producing more scale and sludge. Metal concentrations above threshold levels affect the microbiological balance of soils and can reduce their fertility where most vital soil pollutants are heavy metals owing to carcinogenic, hazardous, and non-degradable properties The hydrocarbon extraction industries are the source of heavy metals like arsenic, barium, cadmium, chromium, iron, lead, mercury, nickel, vanadium, and zinc which are introduced chiefly through the disposal of produced water and drilling muds where arsenic, cadmium, chromium, lead, and mercury have comparatively higher degree of toxicity. Again, radiation can produce fetus abnormality, sterility, erythema, leukemia, epilation, genetic diseases and cancer in the blood-forming tissue, skin, bone, lung, thyroid and so on. So environmental assessment both for radioactivity and toxic elements concentration have been analyzed for Shahbazpur gas field, Saldanadi gas field and Fenchuganj gas field of Bangladesh in this study. Newly developed integrated in-site hydrocarbon and uranium recovery technology with very low grades of uranium ore deposits and also Th and many other valuable minerals recovery technology is economically feasible. So, core samples from gas reservoir wells of different depth from 1279m to 4091m of these three gas fields have been analyzed for elemental identification with concentrations and radioactivity levels, which can reflect information of the sedimentary formation at greater depth of gas reservoir zone and could be used as baseline data for mentioned technology in near future. Neutron Activation Analysis (NAA) method has been used to represent a set of high-quality elemental data for the core sediments of gas reservoir zone along with rare earth elements (REE) and trace elements more precisely for baseline data and to study the possible elemental contamination from gas reservoir wells to the surface environment due to gas abstraction activity. Elemental abundance analysis of gas field environmental samples for toxic waste elements identification have been done using energy dispersive X-ray fluorescence (EDXRF) method with inter-comparison among NAA and EDXRF methods. In the Shahbazpur gas field, Saldanadi gas field and Fenchuganj gas field environmental soil and sediment samples, the mean concentration of Pb are found to be 70.5 ppm (range in ppm: 7.27 – 113), 493 ppm (range in ppm: 85.5 – 1675) and 107 ppm (range in ppm: 101 - 114) respectively in this study, where the concentration of Pb of upper continental crust (UCC) and world soil median values are 17 ppm and 35 ppm respectively. In the Saldanadi gas field, highest concentration detected for the Pb in the sample is from north side of the waste pumped evaporation pond where, used up batteries of car and other heavy vehicles of this gas field also have been dumped from which very high Pb and Sr concentration can be occurred compared to other environmental soil samples of these gas field areas. The average concentration of As are 26.6 ppm (range in ppm: 9.83 - 43.9), 33.8 ppm (range in ppm: 29.2 - 37.6) and 32.4 ppm (range in ppm:
Optimizing Brain Tumor Classification Through Feature Selection and Hyperparameter Tuning In Machine Learning Models
(Elsevier, 2023-11-24) Tahosin, Mst Sazia; Sheakh, Md Alif; Islam, Taminul; Lima, Rishalatun Jannat; Begum, Mahbuba
"Accurately classifying brain tumors using images is extremely important for prognosis and treatment planning. In this study, we have developed an optimized approach using machine learning techniques to classify brain tumors. Our method involves preprocessing the images, extracting features, selecting the most significant ones, and tuning the model parameters. We utilized filtering, morphological opening, and normalization techniques to enhance image quality and reduce noise. We have extracted 17 features that capture the characteristics of the tumors and identify the seven most distinguishing features through importance analysis. By employing a range of models such as Random Forest, Support Vector Machines, Extreme Gradient Boosting, K Nearest Neighbors, Categorical Boosting, Extra Trees, and Naive Bayes, we achieve an accuracy of 98.0 % after thorough hyperparameter optimization. This research highlights the impact of the feature selection process, along with model tuning, on maximizing classification performance. This approach provides a framework that enables the diagnosis of brain tumors for enhanced clinical decision-making and patient care.
Pioneering study of radioactivity in soil near the Payra 1320 MW Thermal Power Plant, the largest coal-fired thermal power plant in Bangladesh
(2024-09-18) Siraz, M. M. Mahfuz; Reza, Ashik; Khan, Mohammad; Shafiqul Alam, Mohammad; Al Mahmud, Jubair; Rashid, Md. Bazlar; Begum, Mahbuba; Sultana, Nazneen; Khandaker, Mayeen Uddin; Osman, Hamid; Yeasmin, S.
Coal combustion increases atmospheric radioactivity, harming those live in the periphery of coal-fired thermal power plants (CFTPPs). A pioneering study has been performed using a high-purity germanium detector by analysing 30 soil samples collected from distances of 50, 600, 1200, and 3000 metres in the periphery of the largest 1320 MW CFTPP, Payra, Bangladesh. The activity concentrations of 226Ra, 232Th and 40K ranged from 19–32, 31–90, and 420–870 Bq/kg, respectively, with most of the samples show 232Th and 40K levels above global averages. Elevated levels of 232Th and 40K in soil around Payra thermal power plant stem from natural minerals, granitic rocks, ash disposal, coal combustion residues, and environmental factors. Radiological hazard indices, including dose rates and cancer risk, exceed global averages, indicating unsafe radiation exposure for coal miners and locals. These findings are crucial for planning coal-fired power plants and stress the need for municipal regulation of fly ash and health monitoring to mitigate risks for workers and residents.
Pioneering Study of Radioactivity in Soil near the Payra 1320 Mw Thermal Power Plant, the Largest Coal-fired Thermal Power Plant in Bangladesh
(Taylor & Francis Publication, 2024-09-28) Siraz, M. M. Mahfuz; Reza, Ashik; Khan, Mohammad; Alam, Mohammad Shafiqul; Mahmud, Jubair Al; Rashid, Md. Bazlar; Begum, Mahbuba; Sultana, Nazneen; Khandaker, Mayeen Uddin; Osman, Hamid; Yeasmin, S.
Coal combustion increases atmospheric radioactivity, harming those live in the periphery of coal-fired thermal power plants (CFTPPs). A pioneering study has been performed using a high-purity germanium detector by analysing 30 soil samples collected from distances of 50, 600, 1200, and 3000 metres in the periphery of the largest 1320 MW CFTPP, Payra, Bangladesh. The activity concentrations of 226Ra, 232Th and 40K ranged from 19–32, 31–90, and 420–870 Bq/kg, respectively, with most of the samples show 232Th and 40K levels above global averages. Elevated levels of 232Th and 40K in soil around Payra thermal power plant stem from natural minerals, granitic rocks, ash disposal, coal combustion residues, and environmental factors. Radiological hazard indices, including dose rates and cancer risk, exceed global averages, indicating unsafe radiation exposure for coal miners and locals. These findings are crucial for planning coal-fired power plants and stress the need for municipal regulation of fly ash and health monitoring to mitigate risks for workers and residents.