7,585 research outputs found
Tissue-specific DNase I-hypersensitive sites in the 5´flanking sequences of the trytophane oxygenase and tyrosine aminotransferase genes
The genes for tryptophan oxygenase (TO) and tyrosine aminotransferase (TAT) are expressed in a tissue- and development-specific manner and are regulated by glucocorticoids (TO and TAT) and glucagon or its intracellular mediator cAMP (TAT) in rat liver. We have analyzed the chromatin structure of these genes in the vicinity of the 5' ends with regard to DNaseI hypersensitivity and have found DNaseI hypersensitive sites upstream of each of the promoters. Mapping of this region reveals three closely spaced cleavage sites near the TO promoter and a doublet of sites near the TAT promoter. In both genes additional cleavage sites are found further upstream. All hypersensitive sites of both genes are absent in kidney nuclei and therefore appear to be specific for the tissue expressing the genes. A correlation of expression and modified chromatin structure was also observed in a hepatoma cell line expressing TAT but not TO: hypersensitive sites are present in TAT but not in TO chromatin. Upon glucocorticoid induction an additional hypersensitive site is detected approximately 2 kb upstream of the TAT promoter in liver and hepatoma cells
Potential income gains for rural households in North Eastern Thailand through trade with organic products
The study groups households in North Eastern Thailand according their income and grade of specialisation in crop production to derive representative household types. For these household types a linear optimization model is run to calculate net incomes under four scenarios. These are certified organic farming, organic farming in the initial and transitional phase and a self-sufficient farming. Simulations for the different management scenarios show that per ha cash profits are about double under certification while they can only be increased by 30 percent under self-sufficient farming, even under favourable assumptions. But transition costs to organic farming are high due to reduced yields at the beginning. According to the figures and model used, only under certified organic production it pays to hire non household workers. Labour hence is a major limiting factor.organic agriculture, Thailand, household income, Consumer/Household Economics, International Relations/Trade,
The Link Between Ejected Stars, Hardening and Eccentricity Growth of Super Massive Black Holes in Galactic Nuclei
The hierarchical galaxy formation picture suggests that super massive black
holes (MBHs) observed in galactic nuclei today have grown from coalescence of
massive black hole binaries (MBHB) after galaxy merging. Once the components of
a MBHB become gravitationally bound, strong three-body encounters between the
MBHB and stars dominate its evolution in a "dry" gas free environment, and
change the MBHB's energy and angular momentum (semi-major axis, eccentricity
and orientation). Here we present high accuracy direct N-body simulations of
spherical and axisymmetric (rotating) galactic nuclei with order a million
stars and two massive black holes that are initially unbound. We analyze the
properties of the ejected stars due to slingshot effects from three-body
encounters with the MBHB in detail. Previous studies have investigated the
eccentricity and energy changes of MBHs using approximate models or Monte-Carlo
three body scatterings. We find general agreement with the average results of
previous semi-analytic models for spherical galactic nuclei, but our results
show a large statistical variation. Our new results show many more phase space
details of how the process works, and also show the influence of stellar system
rotation on the process. We detect that the angle between the orbital plane of
the MBHBs and that of the stellar system (when it rotates) influences the
phase-space properties of the ejected stars. We also find that massive MBHB
tend to switch stars with counter-rotating orbits into co-rotating orbits
during their interactions.Comment: 22 pages, 8 figures, accepted for publication in Ap
The development of a novel large area building integrated solar collector for pool heating
Unglazed solar collectors have often been used a means of providing low cost heating to swimming pools. However, these systems are typically polymer style âmatsâ that are laid on top of a roof, often leading to poor aesthetics due to their lack of integration with the building itself. This study charts the development of a novel large area unglazed building integrated solar pool heating system (BIT), based on long run sheet metal roofing, from its initial conceptualisation through to its implementation. It discusses the design of the building integrated solar collector modules, the assessment of their performance through theoretical modelling and experimental validation. Subsequently, it shows the scaling of laboratory scale testing to a large area array through modelling and discusses the performance of the system in the âas-builtâ configuration. In doing this, it provides a succinct illustration of the design process for the development of the University of Waikatoâs building integrated pool heating system
Robot-Mediated Interviews with Children : What do potential users think?
Luke Wood, Hagen Lehmann, Kerstin Dautenhahn, Ben Robins, Austen Rayner, and Dag Syrdal, âRobot-Mediated Interviews with Children: What do potential users think?â, paper presented at the 50th Annual Convention of the Society for the Study of Artificial Intelligence and the Simulation of Behaviour, 1 April 2014 â 4 April 2014, London, UK.When police officers are conducting interviews with children, some of the disclosures can be quite shocking. This can make it difficult for an officer to maintain their composure without subtly indicating their shock to the child, which can in turn impede the information acquisition process. Using a robotic interviewer could eliminate this problem as the behaviours and expressions of the robot can be consciously controlled. To date research investigating the potential of Robot-Mediated Interviews has focused on establishing whether children will respond to robots in an interview scenario and if so how well. The results of these studies indicate that children will talk to a robot in an interview scenario in a similar way to which they talk to a human interviewer. However, in order to test if this approach would work in a real world setting, it is important to establish what the experts (e.g. specialist child interviewers) would require from the system. To determine the needs of the users we conducted a user panel with a group of potential real world users to gather their views of our current system and find out what they would require for the system to be useful to them. The user group we worked with consisted of specialist child protection police officers based in the UK. The findings from this panel suggest that a Robot-Mediated Interviewing system would need to be more flexible than our current system in order to respond to unpredictable situations and paths of investigation. This paper gives an insight into what real world users would need from a Robot-Mediated Interviewing system
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