193 research outputs found
Impact of Bashundhara Baridhara Housing Project on the status, abundance and species diversity of fish in Bashundhara Housing lake in Dhaka, Bangladesh
A study on the status of fisheries and environmental impact assessment (EIA) was conducted on Bashundhara Baridhara Housing Project (BBHP), Dhaka, Bangladesh for prediction and measure the effects of housing project related development activities that have already been implemented and planned for future implementation. The project is still under development phase and so far allotted 10,000 plots of different sizes. The study shows that the original water bodies and natural fish production there from have greatly declined due to earth filling carried out for development of land for the housing. The physico-chemical parameters of the existing water body within the project area were found to be suitable for fish farming in the estate. A number of economically important fish species are found available in the existing lake. However, the natural fisheries resources of the existing lake is under great stress due to the changes made in the ecosystem, siltation, construction of building and dumping of house building and household waste materials. This has caused some important fish species of the lake to become critically endangered and vulnerable which have been documented in this paper.
Appropriate regulatory and mitigating measures with respect to water management, disposal of construction garbage and other biomedical toxic substances far away from the water bodies are required to be taken to keep the water safe and suitable for fish production as well as for multipurpose use of the lake water
Status of the shrimp sector in Bangladesh in the context of HACCP and trade issues: a review
Shrimp culture in Bangladesh has emerged as an important aquaculture industry over the last three decades although its culture in greater parts of the farming area is done in traditional ways. In the meantime, the government of Bangladesh has taken necessary measures along with the private sectors to increase production, upgrade processing industries and to promote export performance. Long supply chain in raw material collection, inadequate infrastructure facilities, poor level of cool chain and lack of adequate HACCP-based training on hygiene and sanitation of different groups of people involved in the field level are the main problems of quality loss of raw materials. Shortage of raw materials results in poor capacity utilization of the processing plants. The growth of bagda (P. monodon) hatchery has expanded rapidly over the last few years, remaining mostly concentrated in Cox's Bazar region is enough to meet the target production. However, there is a shortage of pelleted shrimp feed in Bangladesh. A large number of export processors are now producing increasing amounts of value-added products such as individually quick-frozen, peeled and divined, butterfly cut shrimp, as well as cooked products. The export earnings from value added products is about half of the total export value. About 95% of total fish products are exported to European countries, USA and Japan and the remaining to the Southeast Asia and the Middle East. Most of the EU approved shrimp processing industries have been upgraded with laboratory facilities and provided HACCP training to their workers. As of now, HACCP is applied on the processing plants, but to ensure the quality of raw materials and to reduce risks, shrimp farms are also required to adopt HACCP plan. There is increased pressure time to time from importing countries for fish processors to establish effective quality assurance system in processing plants. Fish Inspection and Quality Control (FIQC) of the Department of Fisheries while having moderately equipped laboratories with chemical, bio-chemical and microbiological testing facilities and qualified technical personnel, the creation of facilities for testing of antibiotics is underway. FIQC mainly supervises quality aspects of the processing plants and has little or no control over raw material supply chains from farm to processing plants. Bangladesh export consignments sometimes face rejection due to reported poor quality of the products. Three types of barriers are reported for export of shrimp to EU countries. These are:(1) government participation in trade and restrictive practices (state aid, countervailing duties, state trading enterprises, government monopoly practices), customs and administrative entry procedures (anti-dumping duties, customs valuation, classification, formalities, rules of origin); (2) technical barriers to trade or TBT (technical regulations, standards, testing, certification arrangement); (3) specific limitations (quantitative restrictions, import licensing, embargoes, exchange control, discriminatory sourcing, export restraints, measures to regulate domestic prices, requirements concerning marking, labeling and packaging)
Mini-stop bands in single heterojunction photonic crystal waveguides
Spectral characteristics of mini-stop bands (MSB) in line-defect photonic crystal (PhC) waveguides and in heterostructure PhC waveguides having one abrupt interface are investigated. Tunability of the MSB position by air-fill factor heterostructure PhC waveguides is utilized to demonstrate different filter functions, at optical communication wavelengths, ranging from resonance-like to wide band pass filters with high transmission. The narrowest filter realized has a resonance-like transmission peak with a full width at half maximum of 3.4 nm. These devices could be attractive for coarse wavelength selection (pass and drop) and for sensing applications.Support from the Swedish Research Council (VR) is gratefully acknowledged
Шляхи удосконалення підготовки учнів до олімпіад з фізики
(uk) Стаття присвячена проблемі формування основ методики складання задач та завдань для олімпіад з фізики учнів середніх навчальних закладів освіти.(ru) Статья посвящена проблеме формирования основ методики составления задач и заданий для олимпиад по физике учащихся средних учебных заведений образования
Impact of community-based fisheries management practices on production and species diversity in Turag-Bangshi basin floodplains in Kaliakoir, Gazipur, Bangladesh
The study was conducted to investigate the communities perception and compliance to community-based fisheries management (CBFM) in Turag-Bangshi floodplains under
Kaliakoir, Gazipur District. Measures such as ban on use of the harmful fishing gears, seasonal fishing closure, halt of fry fishing, halt of dewatering of beels and the impact of establishment of sanctuaries on fish production and species diversity were introduced by MACH project. Almost all members of the communities in Turag-Bangshi MACH (Management of Aquatic Ecosystem through Community Husbandry) site welcomed the introduction and complied with the implementation of all management measures which
helped stopped use of harmful fishing gears, ensured survival and breeding of brood fish in the rainy season, protected and allowed fry to grow big, restored lost and degraded fisheries and organized communities for sustainable development of the fisheries. A total of 51 species of fishes were found in Makosh beel (natural depression). Among these, small indigenous species (SIS) under Cyprinidae family (Puntius sophore) was the
most dominant. Many species available in the past recorded disappeared from the Makosh beel due to loss of habitat and industrial pollution that damaged spawning and nursery grounds of fish. Introduction of some selective native endangered species (Nandus nandus, Notopterus notopterus, Ompok pabda and Labeo calbasu) by MACH in the Turag-Bangshi water bodies increased diversity of species from 82 to 95. Over a period of
five years during MACH intervention, the average production remained nearly 200% higher than the baseline production of 57 kg/ha to present 207 kg/ha due to maintaining sanctuaries and the closed fishing seasons. Per capita daily fish consumption of the surrounding communities also increased by 78% (from 27 to 48 g/person/day) which is much higher than the national average fish consumption in Bangladesh. The
implementation of community-based MACH project management measures substantially improved fish habitat, production, consumption and socio-economic conditions of the surrounding communities. The model can be used to improve the floodplains of Bangladesh
1+1 Dimensional Compactifications of String Theory
We argue that stable, maximally symmetric compactifications of string theory
to 1+1 dimensions are in conflict with holography. In particular, the finite
horizon entropies of the Rindler wedge in 1+1 dimensional Minkowski and anti de
Sitter space, and of the de Sitter horizon in any dimension, are inconsistent
with the symmetries of these spaces. The argument parallels one made recently
by the same authors, in which we demonstrated the incompatibility of the
finiteness of the entropy and the symmetries of de Sitter space in any
dimension. If the horizon entropy is either infinite or zero the conflict is
resolved.Comment: 11 pages, 2 figures v2: added discussion of AdS_2 and comment
Magnetic functionality of thin film perovskite hybrids
Organic-inorganic perovskite-like hybrids combine the properties of both the perovskite structure and metal-organic framework compounds. We investigated the magnetic properties of a Cu-based hybrid material grown as a thin film by the Langmuir-Blodgett technique. We show that the long alkyl spacers in the hybrid thin film only slightly reduce the ferromagnetic transition temperature in comparison with the bulk. Most interestingly, the single ion anisotropy is larger for the Cu-based hybrid film than for the bulk hybrid. The hybrid thin film consists of two polymorphs in which the ferromagnetic domains are effectively pinned by an antiferromagnetic phase. This leads to a large enhancement of the coercive field enabling memory functionality. (C) 2018 Author(s).</p
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Exploration of alcohol consumption behaviours and health-related influencing factors of young adults in the UK
Hazardous alcohol consumption is ranked above illicit drug use with regards to health
deterioration and social and economic burden. This study sought to clarify the factors influencing
alcohol consumption and its prevalence in young adults. Demographics, alcohol consumption
and lifestyle information were gathered via anonymous questionnaires during 2011–2019, crossing
Reading, Surrey and Farnborough universities, UK. Controlling for confounders, a multinomial
logistic regression was performed using SAS® 9.4 software. A total of 1440 students (43.5% males,
56.5% females; 54.4% Caucasians) with a mean (SD) age of 19.9 (2.73) were included. Among them,
68.9% consumed alcohol frequently and 31.7% had �12 units/week. Statistical analysis revealed that
males consumed twice more alcohol than females, odds ratio (OR) 1.67 (95% confidence interval
(CI) = 1.34–2.09), p-value < 0.01. Caucasians consumed up to five times more alcohol than other
ethnicities, OR 4.55 (3.57–5.56), p-value < 0.01. Smokers consumed three times more alcohol than
non-smokers, OR 2.69 (1.82, 3.99), p-value < 0.01. In general, the levels of alcohol consumption
were positively associated with the levels of physical activity, OR 2.00 (1.17–3.42), p-value < 0.05 and
negatively associated with recreational sedentary screen-time activities in males, OR 0.31 (0.12–0.86),
p-value = 0.03. Focusing alcohol interventions toward Caucasians, smokers and physically active
students, particularly males, may guide university strategies to reduce alcohol-related societal harm
and risks of morbidity and mortality
Braneworld Dynamics of Inflationary Cosmologies with Exponential Potentials
In this work we consider Randall-Sundrum braneworld type scenarios, in which
the spacetime is described by a five-dimensional manifold with matter fields
confined in a domain wall or three-brane. We present the results of a
systematic analysis, using dynamical systems techniques, of the qualitative
behaviour of Friedmann-Lemaitre-Robertson-Walker type models, whose matter is
described by a scalar field with an exponential potential. We construct the
state spaces for these models and discuss how their structure changes with
respect to the general-relativistic case, in particular, what new critical
points appear and their nature and the occurrence of bifurcation.Comment: 15 pages, 9 figures, RevTex 4. Submitted to Physical Review
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