Study of Orbital Maintenance Concepts

An approach to orbital maintenance is examined, using a maintenance element with the capability of providing a pressurized environment for personnel to perform maintenance functions unhampered by pressure suits. Design of an ideal element is reviewed incorporating limited habitability, electronic and pneumatic bench maintenance capability, critical spares storage racks and bins, manipubtors to assist in EVA, and a maintenance/ repair area. The element may be utilized for extended periods of orbital maintenance for providing maintenance services to other orbiting vehicles

Evolution of red wines II. An assessment of the role of acetaldehyde

Factors influencing formation and utilisation of acetaldehyde during red vinification have been examined, with emphasis on its production during primary fermentation and depletfon during early maturation.Acetaldehyde concentrations in new wines were controlled at predictably low levels by addition of SO2 at 30- 50 mg/l before fermentation. There was no appreciable effect from yeast strain, pH or temperature on acetaldehyde production. Significant decrease in acetaldehyde, a-ketoglutaric acid and pyruvic acid, with release of free SO2, occurred during malolactic fermentation. The rate of acetaldehyde consumption in sterile-filtered wine was increased at higher te·mperature and decreased by the presence of free SO2 at high levels. Progressive change in pigment composition of new wines was not influenced by variation in bound acetaldehyde within the range 2-103 mg/l.Acetaldehyde concentration also decreased in a majority of red wines during conservation in commercial cellars. Increases were attributed to abnormal conditions of wine exposure to air. lt was concluded that acetaldehyde formation in wine is probably a surface phenomenon, involving autoxidation of ethanol at the wine interface with atmospheric oxygen. Increase in acetaldehyde during vinification was considered to be adverse in relation to sensory properties and stability of red wine

Communicating Veganism: Evolving Theoretical Challenges to Mainstreaming Ideas

Veganism, as both a philosophy and social movement, faces numerous challenges to the communication of its ideas across society. As a unique modern counterculture, it stands in contravention of prevailing anthropological discourses that dominate conceptual frameworks. This has led to difficulty in constructing updated virtue epistemologies that result in veganism as a logical moral conclusion. It is clear that new social discourses need developing, and that this is a primary concern for affirming moral agency. To explain this and identify key issues and features, vegan communications are evaluated herein from a philosophical, psychological, and informational perspective, with a view of both historical and modern social contexts. In doing so, a number of novel theoretical reflections are offered. This is done through a discussion separated into four sections dealing first with a view of veganism in evolution, secondly with the social complexity of media trends and social positioning, thirdly with achieving constructive dialogue given present-day challenges, and finally with a discussion of modern information systems. Overall, this broad systems view of veganism in society leads to the conclusion that an up-to-date vegan communication theory must necessarily incorporate such diversity considerations, and must also generate a new discourse that is in line with the complex nature of social dynamics and individual development. Done prudently, this could propel vegan ideas further into the mainstream of conversation and consciousness, fostering a new paradigm for consumption

Salivaricin G32, a Homolog of the Prototype Streptococcus pyogenes

Salivaricin G32, a 2667 Da novel member of the SA-FF22 cluster of lantibiotics, has been purified and characterized from Streptococcus salivarius strain G32. The inhibitory peptide differs from the Streptococcus pyogenes—produced SA-FF22 in the absence of lysine in position 2. The salivaricin G32 locus was widely distributed in BLIS-producing S. salivarius, with 6 (23%) of 26 strains PCR-positive for the structural gene, slnA. As for most other lantibiotics produced by S. salivarius, the salivaricin G32 locus can be megaplasmid encoded. Another member of the SA-FF22 family was detected in two Streptococcus dysgalactiae of bovine origin, an observation supportive of widespread distribution of this lantibiotic within the genus Streptococcus. Since the inhibitory spectrum of salivaricin G32 includes Streptococcus pyogenes, its production by S. salivarius, either as a member of the normal oral microflora or as a commercial probiotic, could serve to enhance protection of the human host against S. pyogenes infection

WEIBULL BASED METHODOLOGY FOR CONDITION ASSESSMENT OF CAST IRON WATER MAINS AND ITS APPLICATION

Abstract A qualitative and quantitative understanding of how cast iron water distribution pipes fail in service would facilitate a targeted approach to the management of rehabilitation in the water industry. This paper proposes a technique for assessing the condition of pipes, based on strength characteristics obtained from small samples; this offers an alternative way of estimating the likelihood of failure to current methodologies based on pit-depth measurements. Examination of recovered pipe samples indicates that the strength of the cast iron pipe reduces over time as a result of corrosion, although other time-dependent processes, such as fatigue, may also contribute to this degradation. Taken with previous work, this paper suggests that the variation in strength of small samples removed from cast iron water distribution pipes can be characterised using Weibull methods. It is argued that the Weibull modulus provides a useful indicator of the condition of the pipe. Using scaling arguments, inherent in the Weibull methodology, it is then possible to use data from small samples to predict the likely strength characteristics of water distribution pipes in the ground, which is reasoned to be a good measure of the potential performance of the pipe in service. The Weibull approach is applied to a number of different data sets obtained from testing samples extracted from a range of pipes, which have seen service at various locations in the Thames Water region. One of these data sets was from locations where failure had occurred in service. It is shown that the use of Weibull analysis can identify pipes in the network that have degraded the most significantly. A methodology is suggested whereby this information taken with other performance indicators can be used to identify the local regions where rehabilitation is required most urgently. Alternatively it can be used to identify those regions of the network which are in good condition and unlikely to need repair or replacement work

Detection of putative new mutacins by bioinformatic analysis using available web tools

In order to characterise new bacteriocins produced by Streptococcus mutans we perform a complete bioinformatic analyses by scanning the genome sequence of strains UA159 and NN2025. By searching in the adjacent genomic context of the two-component signal transduction system we predicted the existence of many putative new bacteriocins' maturation pathways and some of them were only exclusive to a group of Streptococcus. Computational genomic and proteomic analysis combined to predictive functionnal analysis represent an alternative way for rapid identification of new putative bacteriocins as well as new potential antimicrobial drugs compared to the more traditional methods of drugs discovery using antagonism tests

Oral flora in acute stroke patients: a prospective exploratory observational study

Objective: To describe the bacterial profile of the oral flora during the first two weeks following a stroke, examining changes in the condition of the oral cavity and infections. Background: Dysphagia is common after a stroke and can lead to aspiration pneumonia. Oral flora changes associated with stroke have been implicated as a possible source of bacteria that can cause systemic infections. Materials and methods: Seventy-seven participants were recruited over a period of nine months. Fifty participants had a complete set of swabs taken from four different oral sites and saliva at three time points over a 14 day period. Molecular identification of bacteria was performed on pooled DNA extracted from swabs. Results: A total of 103 bacterial phylotypes were identified, 29 of which were not in the Human Oral Microbiome Database (HOMD). Fourteen of the twenty most common bacterial phylotypes found in the oral cavity were Streptococcal species with Streptococcus salivarius being the most common. The condition of the oral cavity worsened during the study period. Fifteen (30%) patients had at least one infection. Conclusions: It is unknown whether the 29 phylotypes identified that were not in the HOMD indicate a particular change in the oral flora associated with stroke, or the incomplete nature of the HOMD. The Holistic and Reliable Oral Assessment Tool detailed how the condition of the oral cavity following a stroke worsened over the fourteen days in hospital. Further research is needed to explore oral care methods to improve patient safety and comfort following a stroke

Contribution of Exogenous Genetic Elements to the Group A Streptococcus Metagenome

Variation in gene content among strains of a bacterial species contributes to biomedically relevant differences in phenotypes such as virulence and antimicrobial resistance. Group A Streptococcus (GAS) causes a diverse array of human infections and sequelae, and exhibits a complex pathogenic behavior. To enhance our understanding of genotype-phenotype relationships in this important pathogen, we determined the complete genome sequences of four GAS strains expressing M protein serotypes (M2, M4, and 2 M12) that commonly cause noninvasive and invasive infections. These sequences were compared with eight previously determined GAS genomes and regions of variably present gene content were assessed. Consistent with the previously determined genomes, each of the new genomes is ∼1.9 Mb in size, with ∼10% of the gene content of each encoded on variably present exogenous genetic elements. Like the other GAS genomes, these four genomes are polylysogenic and prophage encode the majority of the variably present gene content of each. In contrast to most of the previously determined genomes, multiple exogenous integrated conjugative elements (ICEs) with characteristics of conjugative transposons and plasmids are present in these new genomes. Cumulatively, 242 new GAS metagenome genes were identified that were not present in the previously sequenced genomes. Importantly, ICEs accounted for 41% of the new GAS metagenome gene content identified in these four genomes. Two large ICEs, designated 2096-RD.2 (63 kb) and 10750-RD.2 (49 kb), have multiple genes encoding resistance to antimicrobial agents, including tetracycline and erythromycin, respectively. Also resident on these ICEs are three genes encoding inferred extracellular proteins of unknown function, including a predicted cell surface protein that is only present in the genome of the serotype M12 strain cultured from a patient with acute poststreptococcal glomerulonephritis. The data provide new information about the GAS metagenome and will assist studies of pathogenesis, antimicrobial resistance, and population genomics

Prospects for the development of probiotics and prebiotics for oral applications

There has been a paradigm shift towards an ecological and microbial community-based approach to understanding oral diseases. This has significant implications for approaches to therapy and has raised the possibility of developing novel strategies through manipulation of the resident oral microbiota and modulation of host immune responses. The increased popularity of using probiotic bacteria and/or prebiotic supplements to improve gastrointestinal health has prompted interest in the utility of this approach for oral applications. Evidence now suggests that probiotics may function not only by direct inhibition of, or enhanced competition with, pathogenic micro-organisms, but also by more subtle mechanisms including modulation of the mucosal immune system. Similarly, prebiotics could promote the growth of beneficial micro-organisms that comprise part of the resident microbiota. The evidence for the use of pro or prebiotics for the prevention of caries or periodontal diseases is reviewed, and issues that could arise from their use, as well as questions that still need to be answered, are raised. A complete understanding of the broad ecological changes induced in the mouth by probiotics or prebiotics will be essential to assess their long-term consequences for oral health and disease

A hydro-socio-legal conception of rights for water: addressing jurisprudential tensions to foster responsive legal regimes

In the space of ten years, a number of novel and unique legal developments have arisen in different jurisdictions around the world with one element in common: a declaration of the Rights of Nature, and a direct attribution of this jurisprudence to watercourses in their respective contexts. This thesis uses a hydro-socio-legal approach to analysing three of these developments as case-studies, identifying why they have occurred, the tensions involved, and the institutional and governance issues that they seek to address or are responding to. This work frames the analysis around an evaluation of environmental constitutionalism, and legal personhood, which informed their selection. This evaluation is prefaced by a prior discussion of key ideas in the theoretical discourse pertaining to the appropriate form of a right for non-human entities, and whether natural objects can have identifiable, and representable, interests. This work concludes that sufficient sophisticated recognition and processing of information about socio-hydrologies in respective contexts can innovate water law to enable responsive governance regimes, and the achievement of this depends on whether jurisdictions are prepared to open themselves to new approaches, legitimate stakeholder relationships with watercourses, and technological solutions that can enrich empirical understandings of fair resource allocation and utilisation for both nature and society.</p