ALBERT

Description: Recognizing the importance of methane hydrate research and the need for a coordinated effort, the United States Congress enacted the Methane Hydrate Research and Development Act of 2000. At the same time, the Ministry of International Trade and Industry in Japan launched a research program to develop plans for a methane hydrate exploratory drilling project in the Nankai Trough. India, China, the Republic of Korea, and other nations also have established large methane hydrate research and development programs. Government-funded scientific research drilling expeditions and production test studies have provided a wealth of information on the occurrence of methane hydrates in nature. Numerous studies have shown that the amount of gas stored as methane hydrates in the world may exceed the volume of known organic carbon sources. However, methane hydrates represent both a scientific and technical challenge, and much remains to be learned about their characteristics and occurrence in nature. Methane hydrate research in recent years has mostly focused on: (1) documenting the geologic parameters that control the occurrence and stability of methane hydrates in nature, (2) assessing the volume of natural gas stored within various methane hydrate accumulations, (3) analyzing the production response and characteristics of methane hydrates, (4) identifying and predicting natural and induced environmental and climate impacts of natural methane hydrates, (5) analyzing the methane hydrate role as a geohazard, (6) establishing the means to detect and characterize methane hydrate accumulations using geologic and geophysical data, and (7) establishing the thermodynamic phase equilibrium properties of methane hydrates as a function of temperature, pressure, and gas composition. The U.S. Department of Energy (DOE) and the Consortium for Ocean Leadership (COL) combined their efforts in 2012 to assess the contributions that scientific drilling has made and could continue to make to advance our understanding of methane hydrates in nature. COL assembled a Methane Hydrate Project Science Team with members from academia, industry, and government. This Science Team worked with COL and DOE to develop and host the Methane Hydrate Community Workshop, which surveyed a substantial cross section of the methane hydrate research community for input on the most important research developments in our understanding of methane hydrates in nature and their potential role as an energy resource, a geohazard, and/or as an agent of global climate change. Our understanding of how methane hydrates occur in nature is still growing and evolving, and it is known with certainty that field, laboratory, and modeling studies have contributed greatly to our understanding of hydrates in nature and will continue to be a critical source of the information needed to advance our understanding of methane hydrates.

Description: Vibrios are rod-shaped bacteria, and are a functionally and phylogenetically diverse grouping of Gram-negative microbes found widely in aquatic, estuarine, and marine habitats. Approximately a dozen Vibrio species are known to cause disease in humans, and infection is usually initiated from exposure to seawater or consumption of raw or undercooked seafood. Although a wide range of different bacterial species contain multiple chromosomes, Vibrio species are noted in that they possess two circular chromosomes. Bacteria of the genus Vibrio are commonly found in tropical and temperate coastal and estuarine waters. Vibrios are among the most common bacteria that inhabit surface waters throughout the world and are responsible for a number of severe infections both in humans and animals. Vibriosis is characterized by diarrhea, primary septicemia, wound infections, or other extraintestinal infections. Select strains of V. cholerae, V. parahaemolyticus, V. vulnificus, and V. alginolyticus are perhaps considered the most serious human pathogens from this genus. Two Vibrio species in particular, V. vulnificus and V. parahaemolyticus are significant foodborne human pathogens, and most frequently infections occur via the consumption of naturally contaminated shellfish produce. It is worth noting that these pathogens represent a significant cause of morbidity and mortality. For example, an estimated 80,000 people contract Vibrio infections each year in the United States, with a sizeable fraction originating from foodborne sources, such as consumption of raw or undercooked seafood produce. Recent data from the Centers for Disease Control and Prevention (CDC) in the United States have indicated that there has been a significant increase in reported infections associated with vibrios, particularly in the last two decades. The annual incidence of reported vibriosis per 100,000 population has increased significantly in the United States from 1996 to 2010, highlighting the importance of these pathogens from a clinical context. Calculations based upon probable incidence of vibriosis have estimated that V. vulnificus and V. parahaemolyticus are the first and third most costly marine-borne pathogens, costing $233 and $20 million, respectively. From a foodborne perspective V. vulnificus and V. parahaemolyticus represent the major pathogens from the Vibrio genus in terms of clinical impact and relevance, and as such this chapter is mostly concerned with these species. These taxa do not sustain prolonged presence in clinical or agricultural settings, where it would likely undergo human-induced selection for antibiotic resistance. As such, these bacteria represent a particularly interesting group of pathogens to study antibiotic resistance, as they provide a “snapshot” of resistance presumably acquired from environmental rather than clinical settings. Despite their public-health significance, strains of V. parahaemolyticus and V. vulnificus have not been extensively monitored for antimicrobial resistance, in contrast to enteric pathogens such as Salmonella or Campylobacter. Given their increasing incidence, global distribution, and severity of disease progression (especially V. vulnificus) it is critical to gain a better understanding of the antimicrobial susceptibility patterns of V. vulnificus and V. parahaemolyticus originating from the environment (Shaw et al., 2014). Data from such sources is invaluable, particularly from routine antimicrobial screening of large numbers of environmental and clinical Vibrio strains as it can provide effective baseline data for treatment purposes.