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Application of Spontaneous Potential Monitoring for Inflow Control in Intelligent Wells
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ATD-2 Integrated Arrival/Departure/Surface (IADS) System Specification - Phase 2
The purpose of this document is to capture the core capabilities developed in ATD-2 Phase 2
Regulation of Pseudomonas aeruginosa amidase expression by AmiC
Regulation of amidase synthesis in P.aeruginosa has been studied using cloned genes from strains PACl and PAC433. Using in vitro constructed rearrangements, deletions and insertions, a new gene amiC has been identified between the amidase structural gene iamiE) and the positive regulator gene (amiE). Transcomplementation studies in E.coli and P.aeruginosa and analysis of in vitro constructed amiC- mutants has shown that AmiC is a negative regulator of amidase expression. The DNA sequence of the amiC region has been determined and two potential ntrA dependent promoters identified upstream of amiC. amiC and amiR expression vectors were constructed for complementation analysis in E.coli and P.aeruginosa. Using the amiC expression vector in P.aeruginosa, AmiC was purified to homogeneity. The purified amiC was shown to have protein kinase activity in vitro. A model has been proposed whereby the transcription antitermination activity of AmiR is modified by AmiC dependent phosphorylation. DNA sequencing studies completed the sequence of the entire 5.3kb Hin-dIII-Sa/I P.aeruginosa DNA fragment containing the amidase genes and two additional open reading frames were identified, giving the gene order for the operon, amiEYCRX. A transcription terminator was identified downstream of amiE. Transcript analysis of the amidase operon has shown constitutive expression from the amiE σ70-dependent promoter. Under inducing conditions, appproximately 40% of the amiE transcripts read through the downstream terminator sequence and into amiY, C, R, X. Studies designed to investigate the role of the ntrA dependent promoters failed to identify transcripts starting from these positions. However amidase expression from the cloned genes was shown to be regulated by the enteric ntr system. These investigations showed that σ54-holoenzyme functions to down-regulate amidase expression in E.coli and P.aeruginosa. The roles of AmiY and AmiX have not been established. However AmiY contains a consensus nucleotide binding domain and amiX shows the characteristics of an integral membrane protein
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Understanding what needs to be done to improve a school
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The purpose of this research is to discover different ways of understanding what needs to be done to improve a school, with particular reference to secondary school head teachers. The variation within those understandings, and how the understandings are logically and hierarchically related, are also of interest. Contributions of theory and knowledge to the quality of head teachers' thinking, in terms of negotiating personal and collective meanings, and implying interventions based on interpretations, are suggested. It is argued that the place of thinking (feeling and awareness) within school improvement is supreme, as thinking determines action, and we can only act in relation to how we perceive, experience, or understand a situation. The relevant literature offers indicators of effective schools, helpful descriptors for aspects of the school improvement processes, suggestions for leadership actions, examples of expert practitioners, and a wide spectrum of theories of organisations and education management. What it does not consider is how this knowledge might combine and interact with experience to form different ways of understanding what needs to be done to improve a school. This research addresses the identified gap in the literature, and deepens our knowledge of the inner aspects of school improvement for both theorist and reflective practitioner. The distinct understandings are derived from two sources, a range of literature that can be related to school improvement, and some empirical research consisting of a simulation exercise undertaken by 18 secondary school head teachers. A particular type of critical analysis is applied to the literature, and a phenomenographical approach is adopted for the scrutiny of the empirical data. Phenomenographic principles are utilised throughout the research, as they represent the only approach concerned directly with the different ways of understanding a phenomenon, and the relationships between understandings. From a range of literature, four abstracted understandings of what needs to be done to improve a school are discovered. They are based on reflecting on excellence, adapting leadership, interpreting the organisation, and developing the inter-dependence of active learning. Each understanding offers a framework through which specific aspects of the relevant literature can be interpreted, applied and integrated, within a given context. From the empirical research, five ways of understanding what needs to be done to improve a school are discovered. They consist of increasing knowledge diagnostically, encouraging a dynamic environment, involving stakeholders in the re-establishment of priorities, enforcing expectations, and co-ordinating initiatives through development planning. Our understanding of our work is an appropriate point from which to increase our competence, as it determines both what competences we develop, and how we develop them. Competence is increasingly concerned with how a situation is understood, what is required according to that understanding, and taking the necessary action. Competence is a consequence of the interaction between our understandings and the extent to which our work context empowers or controls us. For secondary school head teachers, it is argued that competence is dependent on how they understand what needs to be done to improve a school, and the extent to which their environments enable them to act on their understandings
The storage and secretion of protein by the rat submandibular gland
The proteins secreted by the rat submandibular gland in response to various secretory stimuli have been investigated. The β-adrenergic agonist isoprenaline primarily caused the secretion of glycoproteins, although a number of other species were also present, and the saliva contained a moderate level of proteolytic activity. The ɑ-adrenergic agent phenylephrine acted very differently, causing the secretion of a considerable amount of proteolytic activity, with only a very small amount of glycoprotein present in the secretion. Stimulation of the cervical sympathetic trunk caused the secretion of fluid at all frequencies from 1-20 Hz, and this was mediated via both ɑ and β-adrenoceptors. However, at 20 Hz the proteins secreted were essentially similar to those obtained after phenylephrine, indicating that β-adrenoceptors were not involved in protein secretion. At the lower frequency of 5 Hz protein secretion appeared to be mediated via both a and β-adrenoceptors. Acetyl β-methyl choline and physalaemin were involved mainly with fluid secretion, although acetyl β-methyl choline caused the secretion of some proteolytic activity. Surprisingly this was not the case for parasympathetic nerve stimulation. The effect of reserpine upon the carbohydrate histochemistry of the rat submandibular gland was also investigated. This agent was found to cause an accumulation of carboxylated glycoproteins within the acini, which normally contain a neutral glycoprotein population. This result contrasts with the findings of previous investigations, where reserpine caused a simple accumulation of the glycoproteins normally present in the acini, with no qualitative changes
Alien Registration- Wilson, Stuart W. (Eastport, Washington County)
https://digitalmaine.com/alien_docs/1066/thumbnail.jp
Deliberate Recovery: Exploring the Relationship Between Sleep and Expertise in Athletes
The balance between training stress and recovery is essential in the pursuit of athletic performance; however, characteristics of recovery use among experts have been understudied. This thesis explored deliberate recovery in athletes by examining the relationship between expertise and sleep, a biologically necessary form of recovery. Over a 14-day period, 43 athletes recorded their sleep quantity, quality, and training load. A follow-up questionnaire assessed sleep chronotype and categorized athletes into three skill groups. Elite and pre-elite athletes reported sleeping significantly longer than non-elite athletes, starting significantly earlier in the night. In contrast, elite athletes reported significantly worse sleep quality than both pre- and non-elite athletes, with several possible explanations proposed for this deficit. Results indicate that sleep plays a greater role with higher-skilled athletes, supporting the idea of a differential use of recovery according to athlete expertise and encouraging further replication and exploration of the concept of deliberate recovery
Secretion of extracellular proteins by Aeromonas salmonicida and related species
This thesis describes the study of extracellular enzyme activities secreted by the Gram- negative bacterium Aeromonas salmonicida and related species. Initially, cell fractionation criteria were used to define operationally the cellular and extracellular location of proteins. It was demonstrated that proteins detectable in the extracellular medium of A. salmonicida were selectively secreted beyond the outer membrane and not present as a result of general non-specific release due to cell lysis. Several extracellular enzyme activities were detected in the culture filtrate of A. salmonicida, of which a number of protease and amylase activities were partially characterised. The principal extracellular protease of M, 70000 was purified to homogeneity by a combination of ion-exchange and gel filtration chromatography, while another major extracellular protein of M, 56000 was purified by preparative-SDS-polyacrylamide gel electrophoresis. Rabbit polyclonal antibodies were then raised against these purified extracellular proteins. In assays with trout erythrocytes, haemolytic activity in the culture filtrate was inhibited by pre incubating with antibodies raised against the 56kDa protein, suggesting that this protein is in fact a haemolysin.
After the preliminary studies on the production of extracellular proteins by this organism, a series of experiments was carried out to compare the extracellular protein production of A. salmonicida and related species. The study of strain variation at species and sub-species level, with respect to extracellular protein production, was approached in several ways. Firstly, the strains were examined for the production of extracellular enzyme activity; secondly, polyclonal antibodies raised against the purified extracellular protease and haemolysin enzymes were used in Western blotting experiment to screen strains for cross-reactivity; and lastly, culture filtrates of all strains studied were applied to substrate-SDS-polyacrylamide gels to detect hydrolytic enzyme activity.
It was found that the extracellular protease and haemolysin enzymes were common to the majority of A. salmonicida ssp. salmonicida strains studied. Positive cross- reactivity was also observed with the extracellular fraction of A. hydrophila when probed with A. salmonicida antibodies against the protease and haemolysin activities.
On the evidence of Western blotting, extracellular protein production by other Aeromonas species does not appear to be related to A. salmonicida. Detection of protease and amylase activity in substrate-SDS-polyacrylamide gels allowed a detailed comparison of the hydrolytic enzyme production by members of the Aeromonas genus. The results obtained in this way demonstrated striking honmgeneity of protease and amylase secretion within A. salmonicida ssp. Salmonicida but substantial variation between species and subspecies of the Arromonas genus
The influence of habitat quality on the foraging strategies of the entomopathogenic nematodes Steinernema carpocapsae and Heterorhabditis megidis
Entomopathogenic nematodes (EPN) are soil-transmitted parasites and their foraging strategies are believed to range from ‘ambush’ to ‘cruise’ foragers. However, research on their behaviour has not considered the natural habitat of these nematodes. We hypothesized that EPN behaviour would be influenced by soil habitat quality and tested this hypothesis using 2 EPN species Steinernema carpocapsae (an ‘ambusher’) and Heterorhabditis megidis (a ‘cruiser’) in 2 contrasting habitats, sand and peat. As predicted from previous studies, in sand most S. carpocapsae remained at the point of application and showed no taxis towards hosts, but in peat S. carpocapsae dispersed much more and showed a highly significant taxis towards hosts. H. megidis dispersed well in both media, but only showed taxis towards hosts in sand. In outdoor mesocosms in which both species were applied, S. carpocapsae outcompeted H. megidis in terms of host finding in peat, whereas the opposite was true in sand. Our data suggest that these 2 EPN may be habitat specialists and highlight the difficulties of studying soil-transmitted parasites in non-soil media
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