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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

The Blue Monkey In Golden Bengal : Understanding the colonial policy and socialconditions of the indigo rebellion’s peasant

Islam, Niazul January 2021 (has links)
This thesis investigates some social factors that instigated Bengal’s peasants to revolt against theBritish colonial raj repeatedly. The majority of peasant rebellions of Bengal have been examinedfrom the view of political economy, where the general perspective is that peasants revolted becauseof economic exploitations by planters, landlords, and other classes. However, this study argues forextending beyond the political-economic view, and for the importance of also bringing in overallsocial conditions in the examination of peasant rebellions. From these perspectives, this studyexamines a single case, the Indigo rebellion of Bengal, in relation to colonial policy, institutionalarrangements and peasants’ social condition.Archival data, Indigo commission report of 1860, books, academic articles, political drama, etc.,have been used as data sources for the study. To get a personal experience of the indigo rebellion,I have traveled to some districts where the indigo rebellion occurred and discussed with thepeasants to find some oral history. By applying the case study research method, I have analyzedthe data with the thematic analysis method. Commercialization of agriculture, moral economy, andexpansion of the market economy theory has been applied to analyze the data.This study finds that colonial policy and institutional arrangement created conditions to exploit thepeasants’ labor and wealth. The first significant change brought in Bengal by colonial power wasthe change in land ownership. Because of the Permanent Settlement Act, land became a productof money-making in the colonial state. The second significant effect of colonial rule is the changeof agricultural mode of production. The study also shows the commercialization of agriculture thattransformed the traditional method of agriculture, shifted the entire ‘production risk’ on thepeasants’ shoulders, and created insecurity of peasants’ subsistence. Thus, this study indicates thatBengal’s peasants repeatedly revolted because of colonial institutional arrangements andextractive land, economic, social, and indigo production policies that made peasant life miserable
72

“Jagoron: Awakening” to Gender in Non Governmental Organizations in Contemporary Bengal

Roy, Raili 20 May 2013 (has links)
No description available.
73

Designing Mesoporous Test Sticks for Measuring PFAS Concentrations in Water

Hillås, Amanda January 2022 (has links)
Water contamination through substances called per- and polyfluoroalkyl substances (PFAS) is a worldwide problem. Being able to measure the concentrations of PFAS in water is a first step towards beating this contamination. One alternative is to use a field test kit instead of extensive lab equipment to monitor the contaminated areas. This thesis has investigated the possibility of using amine-functionalized mesoporous carbon as adsorbent to develop a detection method based on adsorbing first PFAS and then dye in aqueous solutions. The non-adsorbed dye concentrations are depending on the amount of PFAS, and hence the colour intensity in the remaining solution is proportional to PFAS concentration. Mesoporous carbon with amine functional groups were chosen as specific adsorbents for PFAS because of its large surface area and high adsorption capacity. It has been shown that some colorants would react in a similar way as PFAS on sorbents and thus can be used as an indicator for the user. In the study, the two most common PFAS, PFOA and PFOS, were studied and Rose Bengal was the dye. The adsorbent’s morphology, pore structure and pore size was verified with scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen sorption before being tested. Adsorption tests were performed using different PFAS concentrations and a dye solution range in order to find three things: the detection range, the ratio powder/solution in order to see a difference, and the adsorption or saturation time for both PFAS and dye. This thesis concluded that even though the adsorbent was not as efficient as predicted, this method could be used for detecting PFAS concentrations down to at least 0.1 pg/ml and could be a possible approach for quick field tests in the future.
74

Investigating the Adsorption of Per- and Polyfluoroalkyl Substances on Amine-functionalized Mesoporous Carbons

SALISU, MOJISOLA January 2023 (has links)
Water pollution is a profound ecological concern, exerting detrimental effects on human well-being, ecological systems, and animal life. Among the emerging contaminants that critically influence water quality and have garnered substantial scientific interest in recent times are per- and polyfluoroalkyl substances (PFAS). It is crucial to investigate the de- velopment of an easy technique for PFAS detection and measurement that can be used for quick analysis. This thesis explores the possibility to use amine-functionalized mesoporous carbon as an adsorbent to develop a detection method based on sequential adsorption of per- and polyfluoroalkyl substances (PFAS) and a dye, Rose Bengal, onto the adsorbent. The hypothesis is that the concentration of non-adsorbed dye is dependent on the amount of PFAS present, making the color intensity of the remaining solution proportional to the PFAS concentration. Mesoporous carbon was chosen as the adsorbent due to their high specific surface area, providing a high adsorption capacity, and the potential to functionalize the surface with amine groups which will attract the PFAS. Rose Bengal was selected as a concentration indicator as it has been shown that it can be used as a proxy for PFAS. In this study, the most prevalent PFAS compounds, namely PFOA and PFOS, were investigated. Prior to testing, the adsorbent underwent characterization using diverse techniques to show the porosity and particle morphology. The adsorption experiments encompassed varying PFAS concentrations and a range of dye solutions to determine the detection range, the powder-to-solution ratio necessary for discernible differentiation, and the adsorption or saturation time for both PFAS and dye. This thesis concludes that it was not possible to detect neither PFOA nor PFOS in the range of 0.1 pg/mL to 1 μg/mL with the setup, even though Rose Bengal adsorption could be detected down to 0.6 μg/mL. It was further observed that amine-functionalized hard templated mesoporous carbon has a higher adsorption capacity compared to the soft templated material.
75

Minds of the madrasa : Islamic seminaries, the State, and contests for social control in West Bengal and Bangladesh

Puri, Nikhil Raymond January 2014 (has links)
This qualitative study analytically compares State-madrasa and inter-madrasa relations in Hindu-majority West Bengal and Muslim-majority Bangladesh. It uses Migdal’s State-in-Society approach to explain the nature and bases of these interactions as expressed in three interrelated arenas: educational, organisational, and political. The central question addressed in the educational arena is why some madrasas (recognised madrasas) respond positively to State-initiated incentives for reform while others (unrecognised madrasas) reject the same. In resolving this puzzle, the study seeks also: 1) to classify madrasas in each setting according to their relative thresholds for engagement with the State; and, 2) to identify how, and to what extent, the State can extend the appeal of its reform scheme to unrecognised madrasas. In the organisational arena, the study focuses exclusively on those madrasas that reject State-initiated reform, asking how they organise independently of the State. A key objective here is to determine how inter-madrasa relations vary between Muslim-minority and –majority contexts, and which specific aspects of the State’s policies most encourage such variation. The study’s third empirical section examines State-madrasa relations as expressed through two phenomena in the political arena. The first phenomenon involves the politicisation of recognised madrasas by the State (represented by political parties and their student wings). The study explicates the mechanisms through which this politicisation occurs, identifies the factors facilitating/impeding such politicisation, and assesses the impact of this politicisation on the political allegiances of individual students. The second phenomenon sees representatives of unrecognised madrasas (attempting to) reach into the State complex by launching madrasa-based political parties. The study focuses on this phenomenon to gauge the relationship between a madrasa man’s careers in the educational, organisational, and political arenas: To what extent can madrasa-based political entrepreneurs leverage influence wielded in the educational and organisational arenas towards success in the political arena? And do those who succeed in entering the State complex use this opportunity to promote the societal interests they represent in the educational arena, or in pursuit of increased authority in the organisational realm?
76

Geochemical significance of arsenic and manganese toxicity in groundwaters from Murshidabad district, West Bengal, India

Sasidharan, Sankar Manalilkada January 1900 (has links)
Master of Science / Department of Geology / Saugata Datta / Mass poisoning of arsenic (As) has affected roughly 60 million people in the Bengal Basin (Bangladesh and West Bengal, India) and 43 million people alone in West Bengal. Elevated levels of Manganese (Mn) is another alarming issue in the groundwaters of this region (MCLs: As<10µg/L and Mn< 0.4mg/L). Four locations in Murshidabad district (south-central part of Bengal Basin) were chosen for this current study. Among the 4 locations, two of them showed high concentration of As (>50 - 4622µg/L; 2009 survey) and they are Beldanga: 23° 56'N& 88°15'E and Hariharpara: 24°3.68'N & 88° 21.63'E. On the other hand: Nabagram (24°12.08'N & 88°13.29'E) and Kandi (23°58.6'N & 88°6.68'E) demonstrated less dissolved As (<10µg/L) in groundwaters. Study areas were located to the west (Nabagram, Kandi) and east (Beldanga, Hariharpara) of the river Bhagirathi, a tributary of the river Ganges, flowing N-S through the district of Murshidabad. Eastern side of the river is occupied by grey colored Holocene sediments and western side has more oxidized orangish-brown Pleistocene sediments. Comparative study of major water quality parameters between these sites revealed high As (10-1263µg/L) and low Mn (0.1-1.3mg/L) in the areas like Beldanga, Hariharpara while low As (0-15µg/L) and higher Mn (0.2-4.2mg/L) in Nabagram and Kandi. The pH range for high and low As areas were 4.5-7.8 and 5.1-8.2 respectively. Phosphates showed values <0.04-2.21mg/L in high As areas and <0.08-2.52mg/L in low areas whereas Cl- values were higher within low As areas (29-200mg/L) and lower within high As areas (3.9-78.4mg/L). Fe(t) and Fe2+ values at high and low As areas were 0-13.5mg/L, 0.01-0.11mg/L and 0-1.4mg/L, 0.04-0.06mg/L respectively. δ18O and δD results revealed that monsoonal precipitation is the major recharge source in this area with some input from the surficial waterbodies as ponds in shallower depths within high As areas. The total As extracted from core sediments in these areas do not show much difference: total As in high and low As areas ranges from 6.4-18 mg/kg. Sequential extraction results revealed that majority of the sediment bound As is present in residual phases (>40%). DOC in groundwaters in high and low As areas were 1.5-3.2 and 0.5-1.3mg/L respectively and they had positive correlation with As within the depth profiles. Dissolved organic matter (DOM) characterization studies indicated that microbial proteins (Tyrosine and Tryptophan) are the major components in the groundwaters in the low As region, whereas high As area groundwaters tend to have higher content of humic DOM (A and C). Cl/Br molar ratio of high As wells were low compared to the low As wells. Current study revealed the importance of organic matters (and not the mineralogy of the sediments) both in sediments and groundwaters in controlling the release of As from sediment, at least in the shallow parts of Bengal delta aquifer and microbial mediated reductive dissolution of FeOOH in the presence of organic matter is the major mechanisms by which sediment bound As (<50m depth) is released into the groundwater. The darker organic matter rich sediments (OM both sediment bound and anthropogenically derived) existing at the depth range 20m-50m with reducing environment persisting in both high and low As areas are possible reasons for elevated levels of As in this region.
77

PREPARATION AND APPLICATION OF CATALYSTS FOR THE STEREOSPECIFIC REDUCTION AND PHOTOOXYGENATION OF OLEFINS IN CONTINUOUS OPERATIONS: A NOVEL METHOD FOR THE PRODUCTION OF ARTEMISININ

Fisher, Daniel C 01 January 2017 (has links)
Over the last two centuries, the discovery and application of catalysts has had a substantial impact on how and what chemicals are produced.Given their broad significance, our group has focused on developing new catalyst systems that are recoverable and reusable, in an attempt to reduce concomitant costs. Our efforts have centered on constructing a recyclable chiral heterogeneous catalyst capable of effecting asymmetric hydrogenations of olefins with high stereoselectivity. A class of phosphinoimidazoline ligands, developed by researchers at Boehringer-Ingelheim, known as BIPI ligands, have proven efficacious in the asymmetric reduction of alkenes. However, these chiral ligands are homogeneous and coordinated to precious metals, rendering them irrecoverable and expensive. To address these issues, our group has derivatized the BIPI ligand-metal complex and immobilized it to the surface of graphene oxide as well as polystyrene. Their efficacy and recyclability toward the asymmetric hydrogenation of a functionalized olefin have been evaluated. Another facet of our work has included developing a cost effective synthetic process to artemisinin, the gold standard drug in the treatment of malaria.As a natural product, artemisinin’s worldwide supply remains highly unpredictable, contributing to great price volatility.Combining the benefits of catalysis and the advantages of continuous flow chemistry, our research has sought to develop an economical approach to convert a biosynthetic precursor, artemisinic acid, to artemisinin in three chemical transformations. High-throughput experimentation allowed us to screen a prodigious number of catalysts and identify those effective in the asymmetric hydrogenation artemisinic acid to dihydroartemisinic acid, the first step in the transformation. This screening directed us to an inexpensive, heterogeneous ruthenium catalyst. The second step of the process includes the photooxygenation of dihydroartemisinic acid, which involves photochemically generated singlet oxygen. We have evaluated a commercially available heterogeneous photocatalyst packed in a transparent bed, surrounded by light emitting diodes in the continuous photooxygenation of dihydroartemisinic acid to dihydroartemisinic acid hydroperoxide. The third and final step, an acid induced hock cleavage, initiates an intricate cascading reaction that installs an endoperoxide bridge to deliver artemisinin. Our process afforded a 57% yield from dihydroartemisinic acid to artemisinin.
78

GAS HYDRATES AND MAGNETISM: COMPARATIVE GEOLOGICAL SETTINGS FOR DIAGENETIC ANALYSIS

Esteban, Lionel, Enkin, Randolph J., Hamilton, Tark. 07 1900 (has links)
Geochemical processes associated with gas hydrate formation lead to the growth of iron sulphides which have a geophysically-measurable magnetic signature. Detailed magnetic investigation, complemented by petrological observations, were undertaken on cores from a permafrost setting, the Mackenzie Delta (Canadian Northwest Territories) Mallik region, and two marine settings, IODP Expedition 311 cores from the Cascadia margin off Vancouver Island and the Indian National Gas Hydrate Program Expedition 1 from the Bengal Fan. Stratigraphic profiles of the fine scale variations in bulk magnetic measurements correspond to changes in lithology, grain size and pore fluid geochemistry which can be correlated on local to regional scales. The lowest values of magnetic susceptibility are observed where iron has been reduced to paramagnetic pyrite, formed in settings with high methane and sulphate or sulphide flux, such as at methane vents. High magnetic susceptibility values are observed in sediments which contain detrital magnetite, for example from glacial deposits, which has survived diagenesis. Other high magnetic susceptibility values are observed in sediments in which the ferrimagnetic iron-sulphide minerals greigite or smythite have been diagenetically introduced. These minerals are mostly found outside the sediments which host gas hydrate. The mineral textures and compositions indicate rapid disequilibrium crystallization. The unique physical and geochemical properties of the environments where gas hydrates form, including the availability of methane to fuel microbiological activity and the concentration of pore water solutes during gas hydrate formation, lead to iron sulphide precipitation from solute-rich brines. Magnetic surveying techniques help delineate anomalies related to gas hydrate deposits and the diagenesis of magnetic iron minerals related to their formation. Detailed core logging measurements and laboratory analyses of magnetic properties provide direct ties to original lithology, petrophysical properties and diagenesis caused by gas hydrate formation.
79

Genomics and Transcriptomics of Hybrid Male Sterility Assessed in Multiple Interspecies Feline Breeds

Davis, Brian W 03 October 2013 (has links)
Hybrid male sterility (HMS) is typically the first mechanism fortifying reproductive isolation resulting from genomic incompatibilities. Three interspecies feline breeds derived from domestic cat crosses to wild cat species (Asian leopard cat and African serval) manifest HMS through several generations of backcrossing before eventually regaining fertility. This work utilized 199 hybrid individuals with varying fertilities in a genome wide association study (GWAS) comprising 63,000 genome wide SNPs. Leveraging these results with whole-testis transcriptome sequencing and quantitative real-time PCR data facilitated the comparison of transcripts in sterile and fertile hybrids. This dissertation describes four loci with highly significant and fifty with moderately significant association to sterility within each individual hybrid domestic breed and combinations of breeds. These associations help identify epistatic targets for hybrid incompatibility contributing to sterility. Comparative QTL mapping between pairs of species provides a framework to describe the accumulation of clade-specific reproductive isolating loci. Detailed exploration of gene misregulation between domestic and hybrid individuals, as well as between littermate hybrids of varying fertilities outlines a pattern of expression consistent with a meiotic sex-chromosome inactivation failure in early generations and apoptotic failure in later hybrid generations. Combining comparative genomic association and transcriptomic characterization among hybrid felids of varying divergence, new insight is gained into the mechanisms of mammalian reproductive isolation.
80

Prevalência de brucelose bovina entre rebanhos fornecedores de leite de um laticínio no município de Itirapuã, Estado de São Paulo /

Medeiros, Marina de Almeida Braga. January 2010 (has links)
Resumo: O estudo teve por objetivo determinar a prevalência da brucelose bovina entre fornecedores de leite de um laticínio situado no Município de Itirapuã, Estado de São Paulo, analisar fatores de risco eventualmente associados à ocorrência de brucelose nos rebanhos estudados e analisar o desempenho de testes sorológicos para detectar a infecção. De uma população de 942 bovinos adultos distribuídos em 55 rebanhos, situados nos municípios de Itirapuã e de Patrocínio Paulista, foi obtida uma amostra voluntária composta por 813 animais, distribuídos em 37 rebanhos cujos proprietários aceitaram participar do estudo. Foi aplicado um questionário, para a obtenção de informações sobre fatores que pudessem estar associados às taxas de prevalência. Foram colhidas amostras de soro sanguíneo de todos animais, as quais foram submetidas ao teste do antígeno acidificado tamponado (AAT), e as amostras positivas nesse teste foram submetidas à reação de fixação de complemento (RFC). Foram obtidas amostras de leite do conjunto de cada rebanho participante do estudo, que foram examinadas pelo teste do anel do leite (TAL). Das 813 amostras de soro sanguíneo colhidas, 26 (3,2%) resultaram positivas na aplicação em série dos testes de triagem (AAT) e confirmatório (RFC), e das 37 propriedades estudadas, 12 (32,4%) apresentaram pelo menos um animal positivo. Os fatores que se mostraram associados à ocorrência de brucelose foram número de animais no rebanho, não utilização da vacina B19 e compra frequente de animais. Não se observou boa concordância entre o TAL, que apontou resultado positivo em quatro (10,8%) dos 37 rebanhos, e os testes sorológicos individuais na detecção de rebanhos infectados / Abstract:The aim of this investigation was to verify the prevalence of bovine brucellosis among milk suppliers of a dairy industry located in the municipality of Itirapuã, state of São Paulo, Brazil, analyze risk factors eventually associated with the occurrence of brucellosis among the herds involved in the study, and compare the performance of serological tests in detecting infected herds. From a population of 942 adult cattle in 55 herds, in the municipalities of Itirapuã and Patrocínio Paulista, a voluntary sample of 813 animals was obtained in 37 herds whose owners agreed in participating in the study. A questionnaire about risk factors that could be associated to the prevalence rates was applied. Serum samples of all the 813 animals were collected and tested by the rose Bengal plate test (RBPT); positive samples were then tested by the complement fixation test (CFT). Milk samples were taken from each can at the industry and tested by the milk ring test (MRT). Of the 813 serum samples, 26 (3.2) tested positive in the serial application of RBPT and CFT, and of the 37 herds, 12 (32.4%) had at least one positive animal. Factors that showed association with the prevalence rate were number of animals in the herd, lack of vaccination with strain 19 and frequent introduction of animals. The agreement between individual serological tests and MRT to detect infected herds was not good, since MRT showed positive results in only four (10.8%) of the 37 herds / Orientador: Luis Antônio Mathias / Coorientador: Iucif Abraão Nascif Junior / Banca: Ângela Cleusa de Fátima Banzatto de Carvalho / Banca: Fernanda Senter Magajevski / Mestre

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