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A significant portion of the scientific effort has been devoted to the detection of endotoxins in pharmaceutical solutions, as they pose major health threats as contaminants even in minute amounts. Conventional methods based on the biological response of endotoxins have been well-established, but as technology advances, many limitations surfaced in the recent years. As a result, information obtained by chemical analytical methods becomes valuable in crossvalidating these results. In addition to providing an overview on the main strategies for detecting the presence of endotoxins, the biological methods are compared with the chemical techniques. The review also investigates future advances aimed toward a more accurate, reliable, and convenient endotoxin test.

This paper elucidates the key flow assurance challenges for China’s first National Deepwater gas field development in South China Sea and the facilities design forming the overall flow assurance management strategy. The discussion covers early stage feasibility studies through current stage of project execution. In addition, the finding of flow assurance analysis serves as key input for start-up and commissioning guidelines as well as operating procedures. The development consists of a semi-submersible, with the Eastern and the Western loops spanning more than 40 km of Subsea Production System (SPS). Due to long subsea tiebacks, integrated flow assurance analysis is rolled out to ensure comprehensive risks analysis and active risks management. In particular, key challenges associated with typical Deepwater characteristics such as high pressure and low temperature are actively managed. With design water depth of more than 1500 m and more than 10 Deepwater subsea production wells, robust flow assurance management strategy is required from early activities such as well unloading, well test, pre-commissioning, first gas, through late life decommissioning. Integrated approach is implemented for overall system thermohydraulics analysis, which is used as basis for key flow assurance assessments, including but not limited to management strategy for hydrate, scales, erosion, and slugging. Detailed management strategy and philosophy are discussed in the main body of this paper. Overall chemical management strategy, for instance, is fully optimized to reduce Health, Safety, Security and Environment (HSSE) impact, coupled with sufficient safety margin to ensure minimum downtime. Through integrated flow assurance analysis, all key risks are identified and actively managed. This shows the importance of integrated flow assurance approach to ensure overall project safety and integrity. More importantly, overall optimization can be successful rolled out when the field is in production. This serves as a positive lesson learned for future Deepwater development in South China Sea.

Along with coral reefs and mangroves, seagrass meadows are being threatened globally Southeast Asia is considered within the area of seagrasses’ cradle of diversity. However, information on the current status of seagrass beds from Southern Viet Nam is limited due to lack of reliable data about seagrass species occurring in the Southeast Asian region. One factor is the difficulty of unambiguous species identification. For example, the leaf morphological characteristics of Halophila ovalis and closely related species are overlapping which leads to misidentifications. In this study, the latest satellite Landsat 8 OLI and SENTINEL-2B image analyses were applied to determine the distribution of seagrass beds in Southern Viet Nam. Detailed morphological and genetic marker analyses were used to determine and update the species composition. The present study together with literature reviews indicate that the total area of seagrass beds from Southern Viet Nam are 10,832.1 ha. 2562 ha (or 19.1%) of seagrass coverage has been lost. The seagrass beds at Phu Quoc Island are the largest with 7579 ha. The occurrence of Halophila major is updated for almost all off-shore islands and open-water areas.

Seagrass beds comprise a unique marine ecosystem that acts as a biofilter in marine environments and serves as a spawning ground and nursery for various species of fish. Long-term monitoring of seagrass beds is critical to understanding the dynamic relationships between the ecosystems and the stresses from natural systems and society. This study investigated temporal changes of seagrass beds in Cam Ranh Bay (CRB), Vietnam using multi-temporal Landsat data from 1996 to 2015. The data were processed through 5 main steps including: (1) image preprocessing to convert Landsat data to the top of atmosphere reflectance (TOA) and to correct atmospheric effects, (2) water column correction to eliminate effects on remotely sensed data of aquatic environments, (3) image classification using a linear mixed model, (4) accuracy assessment using the ground reference data, and (5) change detection of seagrass beds. The classification results compared with the ground reference data indicated that the overall accuracies and Kappa coefficients were higher than 91.7% and 0.8, respectively, in all cases. From 1996 to 2015, the total area of seagrass beds had declined by approximately 25% (66 ha), mainly attributed to coastal development and infrastructure construction.

Seagrass meadows are fragile ecosystems in the coastal zone. Natural disasters, land reclamation and various human activities seem to exert negative impacts on the distribution and biological performance of seagrass beds in Vietnam. In this present study, satellite Landsat TM/OLI image analysis was applied to determine changes in seagrass distribution at Van Phong Bay, Vietnam in the last 30 years. The maximum likelihood decision rule was used to extract seagrass bed distribution data. The error matrix using the in situ reference data for HLM image classification was 81–95% accurate, and Kappa coefficients were between 0.72 and 0.91. The results indicated that 186.2 ha (or 35.8%) of the original seagrass beds were lost in the last three decades at Van Phong Bay, and decline in each specific site may have been due to different causes. Typhoons may have caused the loss of seagrass beds at open-sea sites whereas aquaculture activities, excavation and terrigenous obliteration may have caused such losses in protected sites.