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Viruses are ubiquitous and cause significant mortality in marine bacterial and archaeal communities. Little is known about the role of viruses in the sub-seafloor biosphere, which hosts a large fraction of all microbes on Earth. We quantified and characterized viruses in sediments from the Baltic Sea. The results show that the Baltic Sea sub-seafloor biosphere harbors highly abundant viruses with densities up to 1.8 × 1010 viruses cm−3. High potential viral production down to 37 meters below seafloor in ca. 6000-years-old sediments and infected prokaryotic cells visible by transmission electron microscopy demonstrate active viral infection. Morphological and molecular data indicate that the highly diverse community of viruses includes both allochthonous input from the overlying seawater and autochthonous production. The detection of cyanophage-like sequences showed that viruses of phototrophic hosts may persist in marine sediments for thousands of years. Our results imply that viruses influence sub-seafloor microbial community dynamics and thereby affect biogeochemical processes in the sub-seafloor biosphere.

This dissertation presents three studies applying event study methodology to lodging stock performance and exploring two primary research questions: (a) Is there abnormal stock performance for lodging stocks surrounding specified events that could indicate market inefficiencies that can be exploited by market actors, and, (b) Are there event study methodologies that are more or less robust for use in lodging stock event studies that should be considered in future research? The literature review identifies and discusses the literature in four primary areas: (a) event study methodology; (b) issues identified with event studies conducted within a single industry, in this case the lodging industry (c) a review of hospitality stocks in general; and (d) a discussion of the extant lodging stock event study literature. The dissertation proposes revised procedures for addressing the methodological issues of non-normality and crosssectional dependence in the data through the use of both parametric and nonparametric tests, and the three studies within this dissertation utilized these revised procedures. The first paper, entitled “Parametric and Nonparametric Analysis of Abnormal Stock Return and Volume Activity for Lodging Stock Mergers from 2004 to 2007,” presents a study on the unprecedented number of hotel company mergers that took place between 2004 and 2007. The purpose of this study was to determine, using both parametric and nonparametric event study methodologies, whether there were abnormal stock returns or volume activity in the periods surrounding the merger announcement in the trading of 19 public hotel companies that were merged during this period. The study identified statistically significant abnormal returns only on the merger announcement date and statistically

The anaerobic oxidation of methane (AOM) is a crucial component of the methane cycle, but its enzymatic versatility under environmental conditions remains poorly understood. We use sediment samples collected during IODP Expedition 347 to the Baltic Sea to show that relative abundances of 12CH2D2 and 13CH3D molecules in methane gas trace the reversibility of methyl-coenzyme M reductase during AOM by driving methane towards internal, thermodynamic isotopic equilibrium. These data suggest that 12CH2D2 and 13CH3D together can identify the influence of methanotrophy in environments where conventional bulk isotope ratios are ambiguous, and these findings may lead to new insights regarding the global significance of enzymatic back-flux in the methane cycle.

A new presence/absence method has been developed to count fluorochrome-stained bacterial and archaeal cells on membrane filters using epifluorescence microscopy. This approach was derived from the random distribution of cells on membranes that allowed the use of the Poisson distribution to estimate total cell densities. Comparison with the standard Acridine Orange Direct Count (AODC) technique shows no significant difference in the estimation of total cell populations, or any reduction in the precision of these estimations. The new method offers advantages over the standard AODC in considerably faster counting, as there is no need to discriminate between every potential cell visible on a field and fluorescent detritus, it is only necessary to confirm the presence of one cell. Additionally, the new method requires less skill, so has less reliance on expert counters, and that should reduce inter-counter variability. Although this work used the fluorochrome Acridine Orange, clearly the results are applicable to any fluorochrome used to count bacterial and archaeal cells. This method was developed using enrichment cultures for use with enrichment cultures and aqueous environmental samples where interfering detrital and mineral particles are minimal e.g., freshwater/seawater, therefore, it is not suitable for estimating total cells from sediment samples. This method has the potential for use in any situation where counts of randomly distributed items are made using a grid or quadrat system.

Dynamic Knowledge Management (KM) is a combination of cultural and technological factors, including the cultural factors of people and their motivations, technological factors of content and infrastructure and, where these both come together, interface factors. In this paper a Dynamic KM framework is described in the context of employees being motivated to create profit for their company through product development in high value manufacturing. It is reported how the framework was discussed during a meeting of the collaborating company’s (BAE Systems) project stakeholders. Participants agreed the framework would have most benefit at the start of the product lifecycle before key decisions were made. The framework has been designed to support organisational learning and to reward employees that improve the position of the company in the market place.

This paper is a contribution to the long-standing interest of geographers in the contingent, but the focus is on the politics of contingency (and the contingency of politics).

Prokaryotic activity and diversity of the sulphate-methane transition zone (SMTZ) of sediments from Aarhus Bay sediments were characterised. This zone had elevated sulphate reduction and anaerobic oxidation of methane, along with some stimulation in the total prokaryotic population, but surprisingly no active methanogenesis (acetoclastic or hydrogenotrophic) was detected. The prokaryotic population was similar to that present in other SMTZs with prokaryotes belonging to the Deltaproteobacteria, Gammaproteobacteria, JS1, Planctomycetes, Chloroflexi, ANME-1, MBG-D/Thermoplasmatales and MCG. Many of these groups were then maintained in a long-term (6 month), heterotrophic (10 mM glucose, acetate), sediment slurry enrichment with repeat low sulphate and acetate additions (∼2 mM). Other prokaryotes were also enriched including methanogens, consistent with methane formation, Firmicutes, Bacteroidetes, Synergistetes and TM6. This slurry was then inoculated into deep-well plates containing a matrix of substrate (glucose, acetate) and sulphate concentrations (85 combinations, 2 media) for further selective enrichment of SMTZ bacteria. These results demonstrate that important SMTZ bacteria can be maintained in long-term cultivation under specific conditions. For example, JS1 always grew in mixed culture with acetate or acetate/glucose plus sulphate. Chloroflexi occurred more widespread, including in the presence of acetate, which had previously not been shown to be a substrate for Chloroflexi subphylum I. However, Chloroflexi was always found in association with other organisms and was more dominant in medium with seawater salt concentrations. These results provide more information about the physiology of a range of SMTZ prokaryotes and shows that many can be maintained under mixed heterotrophic conditions, including those with few or no cultivated representatives.

Submarine mud volcanoes are a significant source of methane to the atmosphere. The Napoli mud volcano, situated in the brine-impacted Olimpi Area of the Eastern Mediterranean Sea, emits mainly biogenic methane particularly at the centre of the mud volcano. Temperature gradients support the suggestion that Napoli is a cold mud volcano with moderate fluid flow rates. Biogeochemical and molecular genetic analyses were carried out to assess the methanogenic activity rates, pathways and diversity in the hypersaline sediments of the centre of the Napoli mud volcano. Methylotrophic methanogenesis was the only significant methanogenic pathway in the shallow sediments (0–40 cm) but was also measured throughout the sediment core, confirming that methylotrophic methanogens could be well adapted to hypersaline environments. Hydrogenotrophic methanogenesis was the dominant pathway below 50 cm; however, low rates of acetoclastic methanogenesis were also present, even in sediment layers with the highest salinity, showing that these methanogens can thrive in this extreme environment. PCR-DGGE and methyl coenzyme M reductase gene libraries detected sequences affiliated with anaerobic methanotrophs (mainly ANME-1) as well as Methanococcoides methanogens. Results show that the hypersaline conditions in the centre of the Napoli mud volcano influence active biogenic methane fluxes and methanogenic/methylotrophic diversity.

The aim of this study was to determine the influence of punch type (Jab, Cross, Lead Hook and Reverse Hook) and punch modality (Single maximal, 'In-synch' and 'Out of synch' combination) on punch speed and delivery time. Ten competition-standard volunteers performed punches with markers placed on their anatomical landmarks for 3D motion capture with an eight-camera optoelectronic system. Speed and duration between key moments were computed. There were significant differences in contact speed between punch types (F(2,18,84.87) = 105.76, p = 0.001) with Lead and Reverse Hooks developing greater speed than Jab and Cross. There were significant differences in contact speed between punch modalities (F(2,64,102.87) = 23.52, p = 0.001) with the Single maximal (M+/- SD: 9.26 +/- 2.09 m/s) higher than 'Out of synch' (7.49 +/- 2.32 m/s), 'In-synch' left (8.01 +/- 2.35 m/s) or right lead (7.97 +/- 2.53 m/s). Delivery times were significantly lower for Jab and Cross than Hook. Times were significantly lower 'In-synch' than a Single maximal or 'Out of synch' combination mode. It is concluded that a defender may have more evasion-time than previously reported. This research could be of use to performers and coaches when considering training preparations.

A largely terrestrial, lignite/coal-bearing, 148 m core from the Waikato Basin, New Zealand, was studied, with a multidisciplinary approach, for subsurface microbiology. The top ≈76 m was Latest Miocene-Late Pleistocene (≈0.4–5.5 Ma) sediments, which overlay an unconformity and a previously deeply buried (1,600–2,300 m, × 55–75°C) ≈69 m section of moderately indurated, Late Eocene-Early Oligocene (≈32–35 Ma) deposits. Below this is weathered, Late Jurassic metasedimentary basement rock (145.5–157.0 Ma). Similar cell numbers (mean 1.2 × 106 cm −3 ), high viability (4–32%), intact phospholipids (biomarkers for living Bacteria) and activity (sulphate reduction, DNA replication) occurred heterogeneously throughout the core, including the weathered basement rock. Substantial numbers of viable anaerobic heterotrophic and lignite-utilizing bacteria (means 3.4 × 10 4 , 3.0 × 10 3 cm −3 ) were present throughout the core. This is similar to some deep terrestrial formations but contrasts with the generally exponentially decreasing prokaryotic populations in sub-seafloor sediments. For Bacteria, ≈76% of the 16S rRNA gene phylotypes were similar above (31.98 m) and below (133.55 m) the 76 m unconformity, which together with similar cell numbers indicates limited deep burial impact/palaeosterilization, or effective re-colonisation. Archaeal populations were not dominant being only detected with general primers at 31.98 m and those detected with methanogen functional primers were different above and below the ≈76 m unconformity. Both dominant bacterial (Proteobacteria, Actinobacteria, Firmicutes, Chloroflexi) and archaeal (Miscellaneous Crenarchaeotic Group, Methanosarcinales and Methanobacteriales) sequences were similar to those previously detected in both marine and terrestrial subsurface environments, reflecting the changing depositional conditions of the formation. However, the presence of ANME sequences had not been previously found in the terrestrial subsurface. A large proportion of the bacterial 16S rDNA diversity was cultured (43% of commonest genera). Prokaryotic populations and activity changed with lithology and depth and substrates (formate, acetate, oxalate) may diffuse from high-carbon, lignite/coaly layers to support bacterial populations in adjacent sandy or clay-silt layers.

Gas hydrates and associated high methane concentrations are widely distributed along the boundary of the Nankai Trough off Japan. Radiotracer activity measurements were conducted to estimate current methane production rates in sediment cores at two sites in the eastern Nankai Trough off Tokai containing gas hydrates. Low rates of methanogenesis from CO2 reduction and acetate fermentation were detected within the gas hydrate-stability zone and below the Bottom Simulating Reflector (BSR), but not in sediments from shallow depths (

The Porcupine Seabight Challenger Mound is the first carbonate mound to be drilled (approximately 270 m) and analyzed in detail microbiologically and biogeochemically. Two mound sites and a non-mound Reference site were analyzed with a range of molecular techniques [catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH), quantitative PCR (16S rRNA and functional genes, dsrA and mcrA), and 16S rRNA gene PCR-DGGE] to assess prokaryotic diversity, and this was compared with the distribution of total and culturable cell counts, radiotracer activity measurements and geochemistry. There was a significant and active prokaryotic community both within and beneath the carbonate mound. Although total cell numbers at certain depths were lower than the global average for other subseafloor sediments and prokaryotic activities were relatively low (iron and sulfate reduction, acetate oxidation, methanogenesis) they were significantly enhanced compared with the Reference site. In addition, there was some stimulation of prokaryotic activity in the deepest sediments (Miocene,10 Ma) including potential for anaerobic oxidation of methane activity below the mound base. Both Bacteria and Archaea were present, with neither dominant, and these were related to sequences commonly found in other subseafloor sediments. With an estimate of some 1600 mounds in the Porcupine Basin alone, carbonate mounds may represent a significant prokaryotic subseafloor habitat.

The deep subseafloor biosphere supports a diverse population of prokaryotes belonging to the Bacteria and Archaea. Most of the taxonomic groups identified by molecular methods contain mainly uncultured phylotypes. Despite this several cultured strains have been isolated from this habitat, but they probably do not represent the majority of the population. Evidence is starting to suggest that some of the activities measured, such as sulphate reduction and methanogenesis, reflected in geochemical profiles, are carried out by a small subset of the community detected by molecular methods. It is further possible that heterotrophy may be the most important mode of metabolism in subsurface sediments and heterotrophic microorganisms could dominate the uncultured prokaryotic population. Although, heterotrophy is limited by the increasing recalcitrance of organic matter with depth, this may be counteracted by thermal activation of buried organic matter providing additional substrates at depth.