Benchmarking of a 1D Scrape-off layer code SOLF1D with SOLPS and its use in modelling long-legged divertors

A 1D code modelling SOL transport parallel to the magnetic field (SOLF1D) is benchmarked with 2D simulations of MAST-U SOL performed via the SOLPS code for two different collisionalities. Based on this comparison, SOLF1D is then used to model the effects of divertor leg stretching in 1D, in support of the planned Super-X divertor on MAST. The aim is to separate magnetic flux expansion from volumetric power losses due to recycling neutrals by stretching the divertor leg either vertically or radially.Comment: 31 pages, 17 figures. This is an author-created, un-copyedited version of an article accepted for publication in Plasma Physics and Controlled Fusion. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from i

Bidirectional eukaryotic DNA replication is established by quasi-symmetrical helicase loading.

Bidirectional replication from eukaryotic DNA replication origins requires the loading of two ring-shaped minichromosome maintenance (MCM) helicases around DNA in opposite orientations. MCM loading is orchestrated by binding of the origin recognition complex (ORC) to DNA, but how ORC coordinates symmetrical MCM loading is unclear. We used natural budding yeast DNA replication origins and synthetic DNA sequences to show that efficient MCM loading requires binding of two ORC molecules to two ORC binding sites. The relative orientation of these sites, but not the distance between them, was found to be critical for MCM loading in vitro and origin function in vivo. We propose that quasi-symmetrical loading of individual MCM hexamers by ORC and directed MCM translocation into double hexamers acts as a unifying mechanism for the establishment of bidirectional replication in archaea and eukaryotes

Households’ Water-Use Demand and Willingness to Pay for Improved Water Services in Ijebu Ode Local Government Area, Ogun State, Nigeria

This study examined the households’ water choice decision and willingness to pay for improvement in water services. Data were collected from 216 randomly selected households from the ten sub-zones of Ijebu- Ode local government area, Ogun State. The data were analysed using descriptive statistics, generalized linear demand and logit regression models. Results show that majority of households’ water supply was from private piped/borehole (64.8%) followed by public piped (18.5%), and well (16.7 %,). Also, majority (58.3%) of the households are dissatisfied with the current water supply situation and the households preferred water choices are public piped (64.4%), private piped/borehole (30.1%) and well water (5.6%).. These preferences of household’s water choices were determined by quality, convenience, availability and cost with 35.6%, 33.3%, 18.5% and 12.5% respectively. It was revealed further that household per capita expenditure on water is N60 (US$0.38) per day an equivalent of N1,800 (US$11.5) per month which are significantly higher than current connection charge for public piped per month. The result of generalized linear demand model shows that connection charges, household size, distance to water source, availability and quality of water source, unit price paid per liter,  and marital status were determinants of households’ water choices. Logit regression analysis result shows that marital status, education, connection charges, household size and income are the correlates of willingness to pay for improved water services in the study area. It was recommended that the government and other donor agencies should facilitate the improvements of public water utilities in this area by increasing the number of public piped to cover all the sub- zones of Ijebu Ode and its environs. Keywords: Households,  water-use, Willingness to-pay, Generalized linear demand

Static and dynamic characterization of pull-in protected CMOS compatible poly-SiGe grating light valves

status: publishe