Effect of diazinon 60 EC on Anabas testudineus, Channa punctatus and Barbodes gonionotus

Anabas testudineus, Channa punctatus and Barbodes gonionotus were exposed to 5.62, 6.25, 6.87, 7.50, 8.12 and 8.75 ppm; 1.13, 2.26, 3.39, 4.52, 5.65 and 6.78 ppm; and 2.00, 2.50, 3.00, 3.50, 4.00 and 4.50 ppm of Diazinon 60 EC, respectively. The median lethal concentration (LC50) values of Diazinon 60 EC on A. testudineus, C. punctatus and B. gonionotus were 6.55, 3.09 and 2.72 ppm for 96 hrs of exposure. The fish species showed several abnormal behaviors which included restlessness, arena movements, loss of equilibrium, increased opercular activities, strong spasm, paralysis and sudden quick movements during the exposure. For histopathological studies, A. testudineus, C. punctatus and B. gonionotus were exposed for 7 days to sublethal concentrations of 1.13 and 3.75 ppm; 1.13 and 2.26 ppm; and 1.13 and 2.26 ppm of Diazinon 60 EC, respectively. Hypertrophy, necrosis and pyknosis of hepatocytes, pyknosis and degenerative changes such as necrosis of tubular and haematopoietic cells of kidney were the major histopathological effects

Differential climate change vulnerability among different poverty groups in southwestern Bangladesh: lessons for adaptation planning

This article draws on research findings from fieldwork undertaken in Mongla Upazila of Southwest Bangladesh from 2018 to 2019 to analyse how climate-related vulnerability and adaptation is differentiated among different poverty groups. The principal aim of this research is to investigate complex relationship between vulnerability, poverty, and adaptation in a case study carried out in two rural cyclone-prone areas of southwest Bangladesh, focusing on household level vulnerability and adaptive responses to climate change. The quantitative research strategy was adopted in this research. Specific methods utilized for the data collection process included in-depth questionnaire survey of 98 households. The significance of the results was in the differences of poverty and adaptation choices of the households with differential climate change vulnerability which revealed a complex relationship within vulnerability, poverty and adaptation. This research also highlighted that the poor households with high vulnerability could highly be adaptive through adopting a significant number of adaptations to deal with sudden and gradual changes in climate, but the results also suggest that households who are not poor who have usually low vulnerability, likely to have less adaptive responses than households who have high vulnerability. Moreover, this research is an attempt to reveal the complex relationship among vulnerability, poverty and adaptation that may help to develop more effective adaptation framework than before to deal with climate variability and change

Marketing of small indigenous species of fish (SIS) in three selected fish markets of Mymensingh

A socio-economic survey was conducted round the year in three fish markets at Mymensingh, Bangladesh. The selected markets were categorized as rural market (Sutiakhali market), a peri-urban market (Kamal Ranjeet market, BAU) and an urban market (Notun Bazar market, Mymensingh town). It was learnt from the survey that the availability of Small Indigenous Fish Species (SIS) declined to a great extent over the last few years and at presently many of such fish species are either threatened or at the edge of extinction. The supply of SIS was highest in KR market (37% of total) and more or less similar in Notun Bazar and Sutiakhali fish market (25 and 27% respectively). The total supply of SIS fluctuated from 25% to 35% throughout the year in these markets. About 48 SIS were found in the sampled markets over the survey period. The highest number of species (45) was found in KR market followed by Notun Bazar (42) and Sutiakhali (37) fish markets. During the survey, three critically endangered species namely, schilbid catfish, garua catfish and rita were found in these markets. Beside these, other 11 and 10 species were listed to be endangered and vulnerable respectively. The biodiversity of 21 SIS found in three markets were no threat at all. Three species (guntea loach, Indian glass barb and flying barb) were 'data deficient' as reported by the IUCN Red Book (IUCN-Bangladesh 2000). From the supply point of view small prawn, spotted snakehead, stinging catfish, pool barb, striped dwarf catfish, Gangetic mystus, walking catfish and tank goby were the prominent fish. The least available species found in this survey were lesser spiny eel, barred spiny eel, Gangetic ailia, freshwater garfish, zig-zag eel, flying barb, Ganges river sprat, freshwater river shad and dwarf gourami. The weight of SIS available in Notun bazar was highest and nearly double than other two markets. There was no significant difference recorded in the supply of SIS in Sutiakhali and KR markets. The average monthly SIS supply was 185, 192 and 467 kg in KR, Sutiakhali and Notun Bazar, respectively; therefore, the cumulative average supply was 844 kg per month in three markets. The price of SIS ranged widely from taka 50-450/kg depending on species, location of market, time of purchase and the condition of fish. In general small prawn, ticto barb, dwarf gourami, Gangetic leaffish, and Annandale loach were sold at a lower price (ranged taka 50-100/kg) and these species could be considered at the bottom of the market-price list. Other SIS like walking catfish, climbing parch, butter catfish, cotio and schilbid catfish valued as highest price (ranged taka 150-450/kg). There was no specific marketing chain for SIS in Mymensingh region. The components of marketing channels and their expansion varied with seasons and locations. The general pattern, however, was as this - after buying fish from fish farmer/fishermen, middlemen (locally known as Foria) used to buy fish to wholesale market and sell to the wholesalers. The retailers used to buy fish from wholesaler through auction to the highest bidders. The retailers then send the fish to particular market where the fish reached the consumers. The livelihood strategy of SIS retailers in three fish markets showed that socio-economic constraints such as low income, poor educational background, low economic status and lack of capital are the main constrains [sic]. Most of the retailers proposed that government should control the fish price throughout the year, so that the producers can get reasonable and stable price. Construction of cold storage and preservation facilities at market sites, improvement of road and communication, improvement of physical market facilities and reduction of market chain is essential. Credit facilities, improvement of their standard of living, health and sanitary condition, housing condition, children education and access to drinking water facilities were identified as additional aspects to improve socio-economic condition of SIS retailers

Factors associated with pregnancy complications during antenatal period: an extended GEE approach

The purpose of the paper is to examine the factors affecting pregnancy complications during antenatal period of mothers. The study uses data which have been repeated over time i.e., the nature of the data is longitudinal in type. Thus the generalized estimating equation (GEE) method has been employed to identify the factors associated with the pregnancy complications which constitute binary response. The study reveals important findings. Among others, education of mothers, taking special food during pregnancy and desired index pregnancy are found to be negatively associated with pregnancy related complications i.e., lower risk of complication. Patients visit to health workers during antenatal period is positively associated with identifying the causes of pregnancy related complications. Female literacy and maternal morbidity are intertwined in an inverse relationship i.e., improving the former will reduce the latter. Educated women take better care of themselves. It improves their economic power and ensures a better social and legal status. Pregnant women should take special food in order to get rid of pregnancy related complications

In quest of the better mobile broadband solution for South Asia taking WiMAX and LTE into consideration

Internet generation is growing accustomed to having broadband access wherever they go and not just at home or in the office, which turns mobile broadband into a reality. This paper aims to look for a suitable mobile broadband solution in the South Asian region through comparative analysis in various perspectives. Both WiMAX and LTE are 4G technologies designed to move data rather than voice having IP networks based on OFDM technology. Proving competency in various significant aspects WiMAX and LTE already have made a strong position in telecommunication industry. Again, because of certain similarities in technology; they aren’t like technological rivals as of GSM and CDMA. But still they are treated as opponents and viewed as a major threat in case of the flourishing of each other. Such view point is surely not conducive for getting the best out of them. In this paper various aspects and applications of WiMAX and LTE for deployment have been analyzed. South Asia being the residence of an enormous number of people presents an exciting opportunity for mobile operators, developers and internet service providers. So, every consideration that has been made here also correlates successfully with south Asia i.e. how mass people of this region may be benefited from it. As a result, it might be regarded as a good source in case of making major BWA deployment decisions in this region. Besides these, it also opens the path for further research and thinking in this issue

Drag Reduction And Heating

Paper presented at 2018 Canadian Society of Mechanical Engineers International Congress, 27-30 May 2018.An external force is required to maintain the relative movement of horizontal plates. It is shown that this force is reduced when the plates are subject to a spatially distributed heating. The largest reduction occurs for heating wavelengths of the order of distance between the plates with its magnitude increasing proportionally to the second power of the relevant Rayleigh number. It is shown that a sufficiently strong heating eliminates the need for the driving force altogether. The effect is active only in small Reynolds number flows

Disposal of Sea Bottom Sediments by Use as Raw Material for Concrete Elements

The possibility of using sea bottom sediments as a substitute for fine sand aggregate was investigated for the fabrication of concrete solids and marine reefs. The proportions of raw materials in the concrete mixture were optimized, and the materials were evaluated with by testing their slump, air content, mass change, total shrinkage and compressive strength. In the short term, i.e. a curing age of 3 to 28 days, the compressive strengths of the concrete materials made with the sediments were better than those of the normal concrete blocks. Furthermore, after 187 days of curing, the compressive strengths were 44, 31 and 12 MPa respectively for the concrete products with a water-cement ratio (w/c) by weight of 0.47, 0.69 and 1.15 using the sediments. When the concrete materials were field-tested in the sea for approximately one year, the blocks were not damaged by the sea environment because the compressive strengths were 48, 33 and 14 MPa with w/c = 0.47, 0.69 and 1.15, respectively. Since the concrete blocks constructed with the optimal mix of raw materials had enough solid strength to be used in the sea, it may be unnecessary to add steel reinforcement to this concrete for the specific purpose of constructing marine reefs

Assessment of the fertilizer potential of biochars produced from slow pyrolysis of biosolid and animal manures

Excessive amounts of animal manures and production of a large volume of biosolids pose serious environmental issues in terms of their safe disposal and management. Thermochemical treatment of bio-waste materials via pyrolysis can convert them into value-added products such as biochar-based fertilizers. In this study, fourteen biochars were produced from one biosolid and thirteen animal manures by slow pyrolysis at 300 °C. All feedstock and biochar samples were characterized by determining the yield, and physicochemical and surface properties, including the C-containing functional groups. Principal component and cluster analyses were used to classify the feedstock/biochar materials based on their mineral constituents. The biochar yield of various feedstocks ranged from 39 to 81%, with the highest yield for grain-fed cow manure. The highest N and K content was found in chicken manure biochar (57.8 and 29.2 g kg–1, respectively), while the highest P was found in biosolid biochar (40.5 g kg–1). The specific surface area of biochars ranged from 96.06–110.83 m2 g−1. Hierarchical analyses of the chemical compositions of feedstocks and biochars enabled grouping of the materials respectively into four and five distinguished clusters. Three principal components (PC) explained 86.8% and 83.3% of the variances in the feedstocks and biochars, respectively. The PC1 represented the content of the major nutrients (N, P and K), whereas PC2 and PC3 represented other nutrients (secondary and micronutrients) contents and physicochemical properties (pH and EC). The results of this study suggested that biochars produced from different manures and biosolids may potentially be a source of soil nutrients and trace elements. In addition, different biochars may be applied to different nutrient-deficient soils to avoid plausible nutrient and potentially toxic element contamination. © 2021 Elsevier B.V

Aquaculture for income and nutrition: Final report

The United States Agency for International Development-Aquaculture for Income and Nutrition (USAID-AIN) project, implemented by WorldFish, emphasized technology development for improved fish strains, and capacity building in hatcheries and nurseries for wider dissemination and uptake among small- and medium-scale household and commercial producers. Improving nutritional benefits from household aquaculture investment was also an important activity of the project. Specifically, AIN aimed to increase aquaculture production by developing hatcheries and nurseries, disseminating improved fish and shrimp seed, enhancing farm management skills of smallholder farmers, promoting new technologies to expand commercial aquaculture, developing backward and forward market linkages, supporting policy reform and building capacity of the public and private sectors, which resulted in increased productivity and revenue for farmers. This report also highlights the major achievements of the AIN project between 2011 and 2016

Excitation Intensity Driven PL Shifts of SiGe Islands on Patterned and Planar Si(001) Substrates: Evidence for Ge-rich Dots in Islands

For randomly nucleated SiGe/Si(001) islands, a significantly stronger blue-shift of the PL spectra as a function of the excitation intensity is observed when compared to islands grown on patterned substrates side by side within the same run in a solid source molecular beam epitaxy chamber. We ascribe this different PL behavior to the much larger inhomogeneity of the Ge distribution in islands on planar substrates when compared to islands grown on pit-patterned ones, as observed previously. 3D band-structure calculations show that Ge-rich inclusions of approximately 5 nm diameter at the apex of the islands can account for the observed differences in the PL spectra. The existence of such inclusions can be regarded as a quantum dot in an island and is in agreement with recent nano-tomography experiments