11,407 research outputs found

    Spectroscopic Observations of Twenty-one Faint Cataclysmic Variables Candidates

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    We provide the first minimum light spectroscopic observations for 21 previously known or suspected faint cataclysmic variable candidates. The sources were selected from the Downes et al. (2001) living edition catalog and the identified candidates have minimum light magnitudes of V~18-22. We confirm 15 of the candidates to be cataclysmic variables.Comment: 10 pages, 4 figures, accepted by A&

    The expression of the gene for Azurin from Alcaligenes denitrificans in E. coli : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry at Massey University

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    Azurin is a protein which funtions in electron transport and has been found to bind copper when it is expressed in its native bacterial host. In this thesis the azurin from Alcaligenes denitrificans was used. This protein is 129 amino acids long with a molecular weight of 14. 600 dalions. The azurin coding gene from Alcaligenes denitrificans had previously been cloned into a plasmid which allows an E. coli expression system to be used. Azurin was purified from the E. coli hosts using the same procedures as for purifying copper-azurin from the native hosts but was found to remain apparently impure, according to spectrophotomctric data. Efforts to increase the production of the protein by using different expression systems and by refining the existing expression system failed to increase the apparent yield of copper-azurin. Efforts to refine the purification procedure also failed to increase the amount of copper-azurin that was purified. Various experiments were performed to demonstrate that azurin was expressed and processed correctly in the E. coli host. Protein was expressed in a copper-rich and copper-sparse environment. Copper-azurin was purified from the copper-rich environment, while very little copper-azurin could be extracted from the copper-sparse environment. The results described in this thesis suggest that when azurin from A. denitrificans is expressed in an E. coli host using standard media with no copper added, the predominant form of azurin produced in zinc-azunn. As mutants are going to made of this protein, conditions where the protein would bind only copper were required. The ideal conditions for this are still to be calculated but results from this thesis would suggest that copper concentrations in the region of 0.25 mM lead to 65% incorporation of copper. compared to 17% when no copper is added to the E. coli growth medium. E. coli cells were shown to grow with no apparent inhibition of growth in 3.0 mM of CuSO4. This concentration of copper in the growth medium may allow the production of a much higher ratio of copper-azurin compared to zinc-azurin than has been achieved so far

    GMES-service for assessing and monitoring subsidence hazards in coastal lowland areas around Europe. SubCoast D3.5.1

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    This document is version two of the user requirements for SubCoast work package 3.5, it is SubCoast deliverable 3.5.1. Work package 3.5 aims to provide a European integrated GIS product on subsidence and relative sea level rise. The first step of this process was to contact the European Environment Agency as the main user to discover their user requirements. This document presents these requirments, the outline methodology that will be used to carry out the integration and the datasets that will be used. In outline the main user requirements of the EEA are: 1. Gridded approach using an Inspire compliant grid 2. The grid would hold data on: a. Likely rate of subsidence b. RSLR c. Impact (Vulnerability) d. Certainty (confidence map) e. Contribution of ground motion to RSLR f. A measure of certainty in the data provided g. Metadata 3. Spatial Coverage - Ideally entire coastline of all 37 member states a. Spatial resolution - 1km 4. Provide a measure of the degree of contribution of ground motion to RSLR The European integration will be based around a GIS methodology. Datasets will be integrated and interpreted to provide information on data vlues above. The main value being a likelyhood of Subsidence. This product will initially be developed at it’s lowest level of detail for the London area. BGS have a wealth of data for london this will enable this less detialed product to be validated and also enable the generation of a more detailed product usig the best data availible. One the methodology has been developed it will be pushed out to other areas of the ewuropean coastline. The initial input data that have been reviewed for their suitability for the European integration are listed below. Thesea re the datasets that have European wide availibility, It is expected that more detailed datasets will be used in areas where they are avaiilble. 1. Terrafirma Data 2. One Geology 3. One Geology Europe 4. Population Density (Geoland2) 5. The Urban Atlas (Geoland2) 6. Elevation Data a. SRTM b. GDEM c. GTOPO 30 d. NextMap Europe 7. MyOceans Sea Level Data 8. Storm Surge Locations 9. European Environment Agencya. Elevation breakdown 1km b. Corine Land Cover 2000 (CLC2000) coastline c. Sediment Discharges d. Shoreline e. Maritime Boundaries f. Hydrodynamics and Sea Level Rise g. Geomorphology, Geology, Erosion Trends and Coastal Defence Works h. Corine land cover 1990 i. Five metre elevation contour line 10. FutureCoas

    Apps for local government and mobile web usage

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    Introduction Australia is slowly shifting to the concept of open and transparent governance that relies on a two-way communication system between the Government and citizens. One of the ways in which councils are engaging more with citizens is through the use of smart phone applications, or “apps” as they are more commonly known. App is a term used to describe Internet based applications that run on smart phones and other mobiles devices. Apps help users by connecting them to internet services more commonly accessed on desktop or notebook computers, and can make a website mobile phone viewer friendly. Over one billion of the world’s four billion plus mobiles phones are now smart phones, and at least three billion of all mobile phones are SMS enabled. By 2014, mobile internet-usage will overtake desktop internet usage and already in 2011 and currently more than 50% of all “local” searches are done from a mobile device. Councils can benefit from developing mobile apps as they can provide “…social networking platforms, content creation and sharing tools, weblogs and micro blogging tools that allow for a bidirectional information exchange within governmental organizations and government’s interactions with citizens.” This preliminary report is based upon a desktop search of apps (completed in two stages during Feb-June 2012), some extracts from the draft discussion paper From explanation to engagement: Application and use of social media to enhance local government performance (Anne Howard, ACELG-University of Canberra December 2011) and conclusions of the co-authors. Every effort has been made to compile lists of all relevant apps (Apple iPhone and Android platforms). However, this area of mobile web applications is moving very quickly. New apps are being released every day, and this includes many specifically for local government

    Compassed about with so great a cloud: the witnesses of Scottish episcopal acta before ca 1250

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    This article is the result of examining the witnesses to some 600 episcopal acta. Despite the unequal incidence of survival from one diocese to another and the difficulty of identifying those men who had no surname, it is possible to draw some conclusions from this type of evidence. Some-thing can be said about the bishops' clerks and chaplains, other members of their households and their relatives. There is evidence of considerable continuity of personnel from one episcopate to the next. Promotion, including movement to another diocese, can be traced, as can the arrival, growth in numbers and careers of magistri. Surnames allow a consider-ation of the origins of witnesses. Some light is thrown on the growth of cathedral chapters, the introduction of bishops' officials, the role of the CĂ©li DĂ©, and on clerical dynasties, illegitimacy and pluralism. The Scottish Church is seen to be integrated into the wider Western Church

    Water bathing alters threat perception in starlings.

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    The majority of bird taxa perform water bathing, but little is known about the adaptive value of this behaviour. If bathing is important for feather maintenance then birds that have not bathed should have poorer feather condition, compromised escape ability and therefore increased responsiveness to cues of predation. We conducted two experiments examining the behaviour of captive starlings responding to conspecific alarm calls. Birds that had no access to bathing water showed a decreased willingness to feed and increased their vigilance behaviour following an alarm call. We argue that birds denied access to bathing water interpreted an ambiguous cue of threat as requiring more caution than birds that had access, consistent with higher levels of anxiety. Our results support the provision of bathing water for captive birds as an important welfare measure

    Water bathing alters the speed-accuracy trade-off of escape flights in European starlings

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    Birds of most species regularly bathe in water, but the function of this behaviour is unknown. We tested the hypothesis that water bathing is important in feather maintenance, and hence should enhance flight performance. We manipulated European starlings', Sturnus vulgaris, access to bathing water in a 2 × 2 design: birds were housed in aviaries either with or without water baths for a minimum of 3 days (long-term access) before being caught and placed in individual cages either with or without water baths for a further 24 h (short-term access). We subsequently assessed the speed and accuracy of escape flights through an obstacle course of vertical strings. Birds that had bathed in the short-term flew more slowly and hit fewer strings than birds that were deprived of bathing water in the short term, whereas long-term access to bathing water had no significant effect on flight performance. Thus recent access to bathing water alters flight performance by altering the trade-off between escape flight speed and accuracy. We hypothesize that lack of bathing water provision could increase anxiety in captive starlings because of an increase in their perceived vulnerability to predation. This study therefore potentially provides an important functional link between the expression of natural behaviours in captivity and welfare considerations. © 2009 The Association for the Study of Animal Behaviour

    Can we use starlings' aversion to eyespots as the basis for a novel 'cognitive bias' task?

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    Experiments in humans have shown that changes in emotional (affective) state cause adaptive changes in the processing of incoming information, termed "cognitive bias". For instance, the states of anxiety and depression have been shown to be associated with "pessimistic" judgements of ambiguous stimuli intermediate between stimuli associated with positive and negative outcomes. This phenomenon provides a promising method for objectively assessing animal emotional states and has been successfully demonstrated in preliminary studies. However, the experiments yielding these results required extensive training to establish the necessary positive and negative associations. Here we present an experiment using responses to eyespot stimuli that are naturally aversive to many bird species, and require no explicit associative training. We manipulated the state of wild-caught European starlings (Sturnus vulgaris) by playing one of four possible sounds: starling "threat call" (control manipulation), a sparrowhawk call (i.e. predator), starling alarm call or white noise, on the assumption that the latter three sounds would cause anxiety. Immediately following the auditory stimulus, we recorded the birds' behaviour in the presence of each of three visual stimuli: eyespots, ambiguous eyespots or no eyespots. We hypothesised that there would be an interaction between the state of the birds and their response to eyespots, with birds showing enhanced aversion to ambiguous eyespots when anxious. We found evidence that white noise and alarm calls generated anxiety, and that eyespots were aversive. However, there was no interaction between state and response to eyespots. In an attempt to understand our failure to obtain the predicted cognitive bias, we discuss evidence that the aversive nature of eyespots is not attributable to predator mimicry, and is therefore not modulated by anxiety. © 2009 Elsevier B.V. All rights reserved
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