Як уникнути підйому рівня води?

East Africa’s Lake Victoria provides resources and services to millions of people on the lake’s shores and abroad. In particular, the lake’s fisheries are an important source of protein, employment, and international economic connections for the whole region. Nonetheless, stock dynamics are poorly understood and currently unpredictable. Furthermore, fishery dynamics are intricately connected to other supporting services of the lake as well as to lakeshore societies and economies. Much research has been carried out piecemeal on different aspects of Lake Victoria’s system; e.g., societies, biodiversity, fisheries, and eutrophication. However, to disentangle drivers and dynamics of change in this complex system, we need to put these pieces together and analyze the system as a whole. We did so by first building a qualitative model of the lake’s social-ecological system. We then investigated the model system through a qualitative loop analysis, and finally examined effects of changes on the system state and structure. The model and its contextual analysis allowed us to investigate system-wide chain reactions resulting from disturbances. Importantly, we built a tool that can be used to analyze the cascading effects of management options and establish the requirements for their success. We found that high connectedness of the system at the exploitation level, through fisheries having multiple target stocks, can increase the stocks’ vulnerability to exploitation but reduce society’s vulnerability to variability in individual stocks. We describe how there are multiple pathways to any change in the system, which makes it difficult to identify the root cause of changes but also broadens the management toolkit. Also, we illustrate how nutrient enrichment is not a self-regulating process, and that explicit management is necessary to halt or reverse eutrophication. This model is simple and usable to assess system-wide effects of management policies, and can serve as a paving stone for future quantitative analyses of system dynamics at local scales

A review of ecotourism in Tanzania: Magnitude, challenges and prospects for sustainability

In the recent past, the concept of ecotourism has been promoted in Tanzania as an alternative, low-impact form of tourism that supports conservation of natural resources, preserves local culture, and provides economic benefits to the communities. Existing evidence shows that Tanzania has not utilised most of its ecotourism potential. The actual amount of ecotourism activity in the country is highly localised and relatively minimal due to the following factors: accessibility problems in some protected areas, inadequate infrastructure, and insufficient marketing and promotion. There is a need for regulatory authorities to articulate clear policies, regulations, and guidelines that delineate strategies on how to implement ecotourism activities in most parts of Tanzania. Such strategies should describe how to increase accessibility of ecotourism benefits to local communities, increase local community participation, and elucidate better mechanisms of sharing revenues generated from ecotourism. Given the abundance and diversity of natural and cultural resources in Tanzania, there is still room for growth, particularly in the southern, eastern, and western tourism circuits

Adapting and Validating Scale of Customer Engagement in Online Travel Communities

Increasing attention towards customer engagement has caused its measurement to remain a highly debated issue among scholars. This study adapts and validates measurement scales for customer engagement in Online Travel Communities. It builds on previous studies on scale development for customer engagement. Data were collected from 450 members of Online Travel Communities in eight countries: Australia, Canada, Hong Kong (Chinese territory), New Zealand, Singapore, South Africa, the United Kingdom and the United States of America. The process of adapting and validating the scale involved exploratory factor analysis, testing for differential item functioning, examination of item response theory, confirmatory factor analysis, testing for invariance and criterion validity. The results found that three dimensions (affection, absorption, and interaction) suitably and adequately measure customer engagement in Online Travel Communities.peerReviewe

A review of ecotourism in Tanzania: Magnitude, challenges and prospects for sustainability

In the recent past, the concept of ecotourism has been promoted in Tanzania as an alternative, low-impact form of tourism that supports conservation of natural resources, preserves local culture, and provides economic benefits to the communities. Existing evidence shows that Tanzania has not utilised most of its ecotourism potential. The actual amount of ecotourism activity in the country is highly localised and relatively minimal due to the following factors: accessibility problems in some protected areas, inadequate infrastructure, and insufficient marketing and promotion. There is a need for regulatory authorities to articulate clear policies, regulations, and guidelines that delineate strategies on how to implement ecotourism activities in most parts of Tanzania. Such strategies should describe how to increase accessibility of ecotourism benefits to local communities, increase local community participation, and elucidate better mechanisms of sharing revenues generated from ecotourism. Given the abundance and diversity of natural and cultural resources in Tanzania, there is still room for growth, particularly in the southern, eastern, and western tourism circuits

Coupled human and natural system dynamics as key to the sustainability of Lake Victoria's ecosystem services

Contains fulltext : 135031.pdf (publisher's version ) (Open Access)East Africa's Lake Victoria provides resources and services to millions of people on the lake's shores and abroad. In particular, the lake's fisheries are an important source of protein, employment, and international economic connections for the whole region. Nonetheless, stock dynamics are poorly understood and currently unpredictable. Furthermore, fishery dynamics are intricately connected to other supporting services of the lake as well as to lakeshore societies and economies. Much research has been carried out piecemeal on different aspects of Lake Victoria’s system; e.g., societies, biodiversity, fisheries, and eutrophication. However, to disentangle drivers and dynamics of change in this complex system, we need to put these pieces together and analyze the system as a whole. We did so by first building a qualitative model of the lake's social-ecological system. We then investigated the model system through a qualitative loop analysis, and finally examined effects of changes on the system state and structure. The model and its contextual analysis allowed us to investigate system-wide chain reactions resulting from disturbances. Importantly, we built a tool that can be used to analyze the cascading effects of management options and establish the requirements for their success. We found that high connectedness of the system at the exploitation level, through fisheries having multiple target stocks, can increase the stocks' vulnerability to exploitation but reduce society's vulnerability to variability in individual stocks. We describe how there are multiple pathways to any change in the system, which makes it difficult to identify the root cause of changes but also broadens the management toolkit. Also, we illustrate how nutrient enrichment is not a self-regulating process, and that explicit management is necessary to halt or reverse eutrophication. This model is simple and usable to assess system-wide effects of management policies, and can serve as a paving stone for future quantitative analyses of system dynamics at local scales.18 p

A case of Brunner's gland hyperplasia with features of duodenal cancer

A rare case of Brunner’s gland hyperplasia mimicking duodenal cancer is reported. A 68-year old woman had an elevated lesion in the second portion of the duodenum. Endoscopy after spraying with indigo carmine dye showed a granular appearance and fold convergence. The biopsy specimen suggested hyperplasia without malignancy. However, since the endoscopic features strongly suggested malignancy, endoscopic mucosal resection (EMR) was performed to establish the correct diagnosis. The final pathology diagnosis was Brunner's hyperplasia