2,306 research outputs found
Morphic and principal-ideal group rings
We observe that the class of left and right artinian left and right morphic
rings agrees with the class of artinian principal ideal rings. For an
artinian principal ideal ring and a group, we characterize when is a
principal ideal ring; for finite groups , this characterizes when is a
left and right morphic ring. This extends work of Passman, Sehgal and Fisher in
the case when is a field, and work of Chen, Li, and Zhou on morphic group
rings.Comment: 21 page
Pencil-Beam Surveys for Faint Trans-Neptunian Objects
We have conducted pencil-beam searches for outer solar system objects to a
limiting magnitude of R ~ 26. Five new trans-neptunian objects were detected in
these searches. Our combined data set provides an estimate of ~90
trans-neptunian objects per square degree brighter than ~ 25.9. This estimate
is a factor of 3 above the expected number of objects based on an extrapolation
of previous surveys with brighter limits, and appears consistent with the
hypothesis of a single power-law luminosity function for the entire
trans-neptunian region. Maximum likelihood fits to all self-consistent
published surveys with published efficiency functions predicts a cumulative sky
density Sigma(<R) obeying log10(Sigma) = 0.76(R-23.4) objects per square degree
brighter than a given magnitude R.Comment: Accepted by AJ, 18 pages, including 6 figure
An energy, water and disease disaster management module: a technoeconomic feasibility analysis
Intermittent energy and water supply are current challenges faced by many residents in South Africa. South Africa is one of the more water scarce countries in the world; this coupled with the lack of infrastructure makes it challenging to provide every citizen with their right to basic water and sanitation. With millennium development goal 7C not being addressed in many areas, residents experience sub-standard living conditions, which drastically increases the vulnerability of marginalised groups to epidemics. In the sustainable development goals improving sanitation and drinking water has been identified as one of the most effective and least expensive means of reducing fatalities and increasing public health. There is a need for a mobile laboratory that demonstrates power and water self-sufficiency, which is capable of on-site diagnosis and water treatment. The unit will have the ability to perform independent compliance monitoring of municipal water supply, treat inadequate water and provide surplus electricity to surrounding areas. A literature-based study was performed utilizing several scientific databases to identify current methods of power and water production in previous disaster management and humanitarian relief situations. Based on findings three example laboratories were theoretically designed; structural modelling, systems simulation and optimization and sensitivity analyses were performed with HOMER Pro, PackVol and SketchUp. A cost benefit analysis was performed with the social return on investment methodology. Novel human waste processing was performed with fly ash and simulated faeces. Bacterial species identification in ice samples was performed with the API 20E protocol and limited equipment as a proof of concept for field deployment. A hybrid system consisting of PV panels, a wind turbine and biomass generator showed promise for displaced humanitarian relief camps; with every 1 ZAR capital invested resulting in 3.13 ZAR social benefit. A system consisting of PV panels and a battery bank proved to have the least environmental impact and the grid supply laboratory showed a cheaper cost of energy alternative for needs provision. Fly ash showed potential as in nutrient recovery and as a fertility aid to soil. The units developed function as a means to increase disaster preparedness and humanitarian relief as well a means to improve quality of life for rural marginalize populations
Photographing the Earth G324: The Can Do GeoCam payload
The flight of the Charleston County School District Can Do Project GeoCam payload on STS-57 was the climax of a decade long endeavor to bring the promise and excitement of the space program directly into the classroom. The payload carried four cameras designed to take high resolution photographs of the Earth under the direction of children operating the first ever student control room. During the course of the flight, the students followed the Shuttle's orbital tract, satellite weather images and selected a target list that was sent up to the crew each night as part of the execute package. Targets from this list, as well as ones chosen by the crew visually, resulted in the successful collection of photographic runs at many interesting sites on three on three continents
Guest Editorial
A novel blood test for tuberculosis prevention and treatmen
Federalism and Beyond: The Uncertain Nature of Federal/State Relationships in a Restructuring World
Federalism in the restructuring context has certainly been controversial and filled with uncertainty -- some would say perilous. Some would say the shifts in jurisdiction between federal and state governments are so serious and of such concern that we should really pause before restructuring the electric industries. Some say we have not done the right thing in the telecommunications industry either. This area is certainly filled with potential for competitors and for lawyers. To help us sort it out, we have four distinguished panelists who are going to identify some of the key state/federal jurisdictional issues in the telecommunications and electric industries - how those issues are being resolved and how they are likely to be resolved in the future. And because the telecommunications industry is further along than electricity, we are going to start with those panelists first
Evidence of Titan's Climate History from Evaporite Distribution
Water-ice-poor, 5-m-bright material on Saturn's moon Titan has
previously been geomorphologically identified as evaporitic. Here we present a
global distribution of the occurrences of the 5-m-bright spectral unit,
identified with Cassini's Visual Infrared Mapping Spectrometer (VIMS) and
examined with RADAR when possible. We explore the possibility that each of
these occurrences are evaporite deposits. The 5-m-bright material covers
1\% of Titan's surface and is not limited to the poles (the only regions with
extensive, long-lived surface liquid). We find the greatest areal concentration
to be in the equatorial basins Tui Regio and Hotei Regio. Our interpretations,
based on the correlation between 5-m-bright material and lakebeds, imply
that there was enough liquid present at some time to create the observed
5-m-bright material. We address the climate implications surrounding a
lack of evaporitic material at the south polar basins: if the south pole basins
were filled at some point in the past, then where is the evaporite
Log-normal distribution for correlators in lattice QCD?
Many hadronic correlators used in spectroscopy calculations in lattice QCD
simulations appear to show a log-normal distribution at intermediate time
separations.Comment: 17 pages, 13 figure
“Turning Point”: Evaluating the Impact of a Three-Month UK-Based Clinical Education Training Programme for Physicians from a Chinese Medical School
Purpose: Transnational faculty development programmes are increasingly popular in medicine, although evaluation of such activities rarely considers longer-term outcomes or the impact of language training. This study attempts to fill this gap by evaluating the lasting impacts of a three-month clinical education and English language training programme at University College London Medical School, UK, for medical educators from Ningbo University, China.
Methods: In-depth, semi-structured interviews were conducted in China with 41 participants who had completed the programme between 2013 and 2018. Interview data were analysed using an inductive thematic analysis, and themes were categorised using the four primary components of the faculty development model outlined by Irby and O’Sullivan (2011) – context, facilitator, programme, and participant.
Results: Contextual impacts included the importance of participants learning in the familiar environment of their own clinical discipline, the cultural enrichment gained by spending time overseas, reflecting on differences in health-care systems, and attempts to implement and disseminate learning on return to China. Facilitator-related factors included new insights into the student–educator relationship and valuing the support of programme mentors. Programme-related factors included exposure to new teaching methods and technical presentation skills, the challenges of navigating observership placements, spoken English language and pronunciation issues, and establishing a peer network of medical educators. Participant-related factors included improved confidence and self-reflection, adjusting educational approaches for different student groups, and career development in medical education.
Conclusion: Participants gained teaching confidence from their engagement in the programme and many described it as a turning point in their careers as educators. Although in the period after attending, individuals changed their own practices and influenced colleagues within their organisation, often through taking on senior roles, and systematic education changes were generally not implemented. Dedicated English language classes and clinical placements were considered the most positive features of the programme
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