Search

The ultrafast monitoring of deoxyribonucleic acid (DNA) dynamic structural changes is an emerging and rapidly growing research topic in biotechnology. The existing optical spectroscopy used to identify different dynamical DNA structures lacks quick response while requiring large consumption of samples and bulky instrumental facilities. It is highly demanded to develop an ultrafast technique that monitors DNA structural changes with the external stimulus or cancer‐related disease scenarios. Here, we demonstrate a novel photonic integrated graphene‐optofluidic device to monitor DNA structural changes with the ultrafast response time. Our approach is featured with an effective and straightforward design of decoding the electronic structure change of graphene induced by its interactions with DNAs in different conformations using ultrafast nanosecond pulse laser and achieving refractive index sensitivity of ~3 × 10−5 RIU. This innovative technique for the first time allows us to perform ultrafast monitoring of the conformational changes of special DNA molecules structures, including G‐quadruplex formation by K+ ions and i‐motif formation by the low pH stimulus. The graphene‐optofluidic device as presented here provides a new class of label‐free, ultrafast, ultrasensitive, compact, and cost‐effective optical biosensors for medical and healthcare applications.

Kaptai Lake (KL), the largest inland watershed in Bangladesh (ca. 700 km2) and one of Southeast Asia’s largest artificial reservoirs, features an abundant variety of indigenous fishery species. Moreover, it provides a plethora of ecological benefits to society. Nevertheless, the KL is suffering from multidimensional natural and anthropogenic stressors that threaten these wetlands’ sustainability. Though the legal framework assures sustainable conservation of fisheries resources, the implementation scenarios of fisheries laws, regulations, and policies in the KL wetland are insufficient. This study aimed at assessing the fisher’s perception of the regulation implementation efficiency of the Protection and Conservation Fish Act of 1950, while analyzing the effectiveness of the legal framework in the context of biodiversity conservation and the management sustainability of KL. By integrating qualitative and quantitative data collected through participatory Rural Appraisal (PRA) tools viz. 225 interviews with fishers, four focus group discussions, and 12 key informant interviews, the investigation was performed in four selected areas in KL. The findings show that fishers routinely disregard laws and restrictions of the Protection and Conservation of Fish Act 1950 due to various socioeconomic and political forces. Although the annual fish harvest rate from KL appears to be increasing, the lake is losing its charismatic biological diversity primarily due to inappropriate and ineffective enforcement of fishing regulations. Many fishers believe that they still follow the act’s significant laws and regulations while being involved in several destructive and prohibited fishing practices. There is a link between community awareness, the scope of the act’s provisions, the effectiveness of its enforcement, and the strength of its execution. One of the leading causes of biodiversity loss in the KL is inadequate and ineffective fishing regulations. Improvement in the enforcement of the fishing act may be the prominent option to ensure better biodiversity conservation and sustainable management of this wetland. This result calls for functional and policy attention to revising the regulations to account for socioeconomic and political elements contributing to environmental degradation. This study also highlights the urgent need for transdisciplinary collaboration initiatives and synchronous cooperation among the agencies in order to effectively implement the fishing laws and contribute to better conservation and sustainability of the Kaptai lake fisheries resources.

Tanguar Haor (TH) is considered one of the Ecologically Critical Areas (ECAs) of Bangladesh and is internationally recognized as RAMSAR wetland (2nd Ramsar site) known to provide multiple ecosystem services to the society. Nevertheless, multidimensional threats and stressors, the capacity to supply ESs, and the biodiversity of the TH significantly degrades and threatens this wetland’s conservation and sustainability. Although the legal framework promises the sustainable conservation of fisheries resources, information on the implementation scenarios of fisheries laws, regulations, and policies in the TH Ramsar are scant. By merging qualitative and quantitative data of primary and secondary sources, this research aimed to analyze the legal framework to check the effectiveness of regulations for non-conflicting fisheries resources and the sustainable conservation of the TH Ramsar. Primary empirical data were collected by employing Participatory Rural Appraisal (PRA) tools, i.e., 204 semi-structured questionnaire-based individual interviews with fishers, three focus group discussions, and 14 key informants’ interviews in three fishing villages in the TH. In contrast, secondary data was set by reviewing published literature and related official documents. Results showed that, due to weak enforcement with inadequate surveillance and poor implementation of the legal framework, there was a high non-compliance with fishing laws, rules, and policies. Destructive and prohibited fishing gears, e.g., the use of small mesh fine nylon nets (current jal), purse seine net (ber jal), and the harvesting during ban period-illicit catch were widespread in the study areas. In addition, catching undersized fish, fishing at the restricted areas (sanctuary area), and fishing during spawning seasons occur often. There is a crying need for a comprehensive legal and policy framework to contextualize the local context, ensure the proper implementation of the fishing laws and regulations, increase the managerial inefficiency of enforcing agencies, ensure livelihood support during the fishing ban, and afford good alternative income options are still significant issues for good governance in the Tanguar Haor ECA. Findings might help to identify the gaps and misunderstanding of the existing legal practice while submitting urgent attention to the need for drawing a comprehensive legal and policy framework (contextually modified according to the local context), taking initiatives and acting synchronously for proper implementation, and calling transdisciplinary collaboration and cooperation among the agencies that may ensure the non-conflicting use of the natural resources of the TH that can be also helpful for the better conservation of this Ramsar wetland.

The Meghna river estuary has had substantial importance in supporting the coastal community’s livelihood for decades, but the pressure on it is immense due to many anthropogenic drivers. The present study aimed to assess its ecosystem services (ES) according to the framework of the standard international classification of ecosystem services (CICES). This study also identified the drivers, pressure, state, impact, and responses (DPSIR), and the factors responsible for ES changes in the Meghna river estuarine ecosystems. By merging both quantitative and qualitative data, a total of 19 sub-categories of ES were found, among which eight are provisioning, seven are regulatory, and four are cultural services, according to the CICES framework. From the results, it can be concluded that food provisioning from the Hilsha fishery, the national fish as a part of cultural heritage, and nursery habitat functions were the top provisional, regulatory, and cultural services to the society in the study areas and beyond. However, several threats and stressors of both anthropogenic and natural origins were identified as drivers of ES changes, such as overexploitation, destructive and illegal fishing, heavy river bed siltation, and natural hazards such as extreme cyclonic events, floods, and sea levels rising. This study underlines the urgency of research and policy attention to address the challenges, and of transforming management regimes to an ecosystem-based approach, which is part of nature-based solutions according to the International Union for Conservation of Nature (IUCN), which refers to the present case, and particularly to fishery co-management. Creating alternative income sources and raising community awareness regarding the importance of maintaining the healthy condition of the river basins, and comprehensive compliance with the rules and regulations are proposed in order to ensure these estuarine ecosystems’ sustainability.

By employing empirical and secondary data (qualitative and quantitative), this study demonstrates how social equity (with its three dimensions) can meaningfully address the conservation of the coastal social&ndash, ecological system (SES), without losing diverse ecosystem services (ES) in south-east coastal Bangladesh. Based on this proposition, this study assesses the available ES and identifies the drivers responsible for ES changes, arguing for the application of social equity for resource conservation. The findings show that communities along Bangladesh&rsquo, s south-eastern coast use several ES for food, medicine, income, livelihoods, and cultural heritage. However, this valuable ecosystem is currently experiencing numerous threats and stressors of anthropogenic and natural origin. In particular, large-scale development activities, driven by the blue growth agenda, and neoliberalism policy, pose a risk to the local communities by degrading coastal ecosystem services. Escaping this situation for coastal natural resource-dependent communities in Bangladesh will require a transformation in the governance structure. Implementing the Small-Scale Fisheries (SSF) Guidelines that call for initiating policy change to deliver social justice to small-scale fisheries would help to address coastal ecosystem service conservation in Bangladesh.

The present study was conducted to determine the persistence of oxytetracycline residue in Tilapia (Oreochromis niloticus) available in local fish markets of Sylhet Sadar Upazila. To carry out this experiment, 24 fish samples were randomly collected from four (4) local fish markets under study area from March 2016 to August 2016. Fish samples were analyzed by using High Performance Liquid Chromatography (HPLC) method to detect amount of residues of oxytetracycline. In this study, detectable oxytetracycline residues were observed in five (5) samples of Tilapia ranged between 23.77-39.94 ppb (mean 38.88±2.99 ppb). Oxytetracycline residues less than limit of detection were also found in 19 (79.17%) samples. The detected residues of oxytetracycline in these fish samples did not exceed the maximum residue limit (MRL) 100 ppb recommended by the European Commission. However, long term persistence of high level oxytetracyclines could be a potential hazardous for public health. For this reason supervision of antibiotic uses and monitoring of optimum MRL in Tilapia are utmost needed for farmed fish species.Bangladesh J. Sci. Ind. Res.53(1), 41-46, 2018

This article has been retracted: please see Elsevier Policy on Article Withdrawal ( https://www.elsevier.com/about/our-business/policies/article-withdrawal ). This article has been retracted at the request of Editors-in-Chief of Regional Studies in Marine Science, because there is clear evidence that the findings of this work are unreliable due to inadequacy in the methodology, incorrect use of species names, and unauthorized use of data from organizations affiliated with the authors. We apologize for any inconvenience caused.

The south-east coast, specifically the Cox’s Bazar region, of Bangladesh has achieved a tremendous impetus for producing a large volume of dried fish by involving thousands of marginalized coastal people. This study aimed to assess the socio-economic profile, livelihood strategies, and resilience of the communities engaged in fish drying on the south-east coast using a mixed-methods approach and an Analytic Hierarchy Process (AHP). The study’s findings revealed that communities involved in drying were socio-economically undeveloped due to their lower literacy, unstable incomes, and labor-intensive occupations. Apart from notable child labor employed in fish drying in Nazirertek, female workers had relatively higher participation than males. Nevertheless, the female workers had less control over their daily wages and reported working at USD 3.54–5.89 per day, which was relatively lower than male workers who received USD 4.15–8.31 per day. Through fish drying activities, very few workers, producers, and traders were found to be self-reliant. In contrast, the livelihoods of the workers were not as secure as the processors and traders. In addition to suffering from various shocks and constraints, dried fish processors and workers, dried fish traders, off-season income, an abundance of fish species, fish drying facilities, trader’s association, and social interrelationship played a significant role in maintaining community resilience. The study recommends appropriate interventions to alternative income diversification options, strong collaboration between communities, local authorities, and government for sustainable livelihoods and better community resilience.

The Sundarbans is the largest salt-tolerant tropical mangrove forest in the world occupying complex networks of wetlands situated in the Bengal deltaic plain that shares territories with Bangladesh and India. This chapter explores the goods and services, collectively known as ecosystem services that the Sundarbans deliver to the populations living in the impact zone and to the wider landscape of Bangladesh. Similiar to other wetlands, four types of ecosystem services are derived from the Sundarbans mangrove ecosystem. These are provisioning services (e.g. fish and shellfish, woods, and honey), cultural services (e.g. mangrove tourism, religious value), regulatory services (e.g. carbon sequestration), and other supporting services (e.g. soil formation). Particularly, provisioning services from the Sundarbans help to ensure employment, income, and food security and constitute a last resort activity when all other livelihood options are lost. However, a number of threats and stressors, both of natural and anthropogenic origin, continue to affect the flow and quality of the ecosystem services due to overuse and degradation. This chapter submits that for sustainable delivery of ecosystem services, urgent research and policy attention is required to manage the wetland in a manner that is socially equitable and ecologically sound.