332 research outputs found
Spatial patterns in the evolution of Cenozoic dynamic topography and its influence on the Antarctic continent
Our knowledge of dynamic topography in Antarctica remains in an infancy stage compared to other continents. We assess the space-time variability in dynamic topography in Antarctica by analysing grids of global dynamic topography in the Cenozoic (and late Cretaceous) based on the tomographic model S40RTS. Our model reveals that the Gamburtsev Province and Dronning Maud Land, two of the major nucleation sites for the East Antarctic Ice Sheet (EAIS) were ~500 m higher 60 Ma ago. The increased elevation may have facilitated ephemeral ice cap development in the early Cenozoic. Between ca 25 and 50 Ma the northern Wilkes Subglacial Basin was ca 200 m higher than today and a major increase in regional elevation (>600 m) occurred over the last 20-15 Ma over the northern and southern Victoria Land in the Transantarctic Mountains (TAM). The most prominent signal is observed over the Ross Sea Rift (RSR) where predicted Neogene dynamic topography exceeds 1,000 m. The flow of warm mantle from the West Antarctic Rift System (WARS)may have driven these dynamic topography effects over the TAM and RSR. However, we found that these effects are comparatively less significant over the Marie Byrd Land Dome and the interior of the WARS. If these contrasting dynamic topography effects are included, then the predicted elevations of the Ross Sea Embayment ca 20 Ma ago are more similar to the interior of the WARS, with significant implications for the early development of the West Antarctic Ice Sheet
The effect of largeâscale shearâvelocity heterogeneity on SS precursor amplitudes
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/102095/1/grl51158.pd
An analysis of SS precursors using spectralâelement method seismograms
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/89460/1/j.1365-246X.2011.05256.x.pd
A new wireless underground network system for continuous monitoring of soil water contents
A new stand-alone wireless embedded network system has been developed recently for continuous monitoring of soil water contents at multiple depths. This paper presents information on the technical aspects of the system, including the applied sensor technology, the wireless communication protocols, the gateway station for data collection, and data transfer to an end user Web page for disseminating results to targeted audiences. Results from the first test of the network system are presented and discussed, including lessons learned so far and actions to be undertaken in the near future to improve and enhance the operability of this innovative measurement approac
Tomographic filtering of geodynamic models: Implications for model interpretation and largeâscale mantle structure
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94833/1/jgrb15038.pd
Seismic and mineralogical structures of the lower mantle from probabilistic tomography
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95386/1/jgrb17106.pd
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Facilitators to the integration of the first UK-educated physician associates into secondary care services in the NHS.
The physician associate (PA) profession is relatively new to the British NHS. Little research has been conducted on the facilitators to integrating these new health professionals into a secondary care service. Thus, a grounded theory qualitative study was conducted. PAs who were educated in the UK and were the first PA in their secondary care service were interviewed, as well as doctors who were on the team when the PA started. Ten facilitators were identified, comprising three facilitator themes: PA involvement in role and skill development is crucial; having a champion for the PAs promotes integration; and principled behaviour by the PA allows the role to develop safely and effectively. Having a clearly defined role for the PA is the primary facilitating factor. This research identified approaches that both PAs and hospital trusts can implement to facilitate the introduction of PAs to secondary care services in the NHS
System Architecture for 3D Gravity Modelling
A flexible software architecture for gravity modelling is establishedand the advantage is discussed of having several alternative programs tohandle complex 3D models. The flexible architecture consists of four parts, implemented in a distributed computer environment:the three-dimensional model builders and visualizers (GOCADsoftware, version 7.0), the model representation translators (GOCADsoftware or GEOMOD sofware), the forward simulation algorithmsof gravimetric data (alpplying Talwani-Ewing and Goetze- Lahmeyermethods in the finite-element representation class), and the inversion(model updating) scheme manager based on the Cordell - Hendersoninversion procedure.A good software architecture should at least keep the model building and updating software separate from the forward simulation software. Inversion schemes can then be realized by communication between the two parts of software.Several synthetic cascs are shown to demonstrate the use and thecapability of the architecture and methods applied. The gravity fieldsof complex 3D models, i.e. overhanging and non-overhanging saltdomes, are simulated. The gravimetric anomalies for both cases havevery similar shapes. Gravity modelling can distinguish between these,because the existing mass differences result in anomaly differencesboth for surface profiles and X-sections. The capability of the inversionprocedure is also shown in the discussed synthetic case. The inversion manager is able to create the global structural forms representedas a horizon with constant density contrast (a two-layer model) from residual gravity anomalies.</div
Factors affecting domestic water consumption in rural households upon access to improved water supply: insights from the Wei River Basin, China
Comprehensively understanding water consumption behavior is necessary to design efficient and effective water use strategies. Despite global efforts to identify the factors that affect domestic water consumption, those related to domestic water use in rural regions have not been sufficiently studied, particularly in villages that have gained access to improved water supply. To address this gap, we investigated 247 households in eight villages in the Wei River Basin where three types of improved water supply systems are implemented. Results show that domestic water consumption in liters per capita per day was significantly correlated with water supply pattern and vegetable garden area, and significantly negatively correlated with family size and age of household head. Traditional hygiene habits, use of water appliances, and preference for vegetable gardening remain dominant behaviors in the villages with access to improved water supply. Future studies on rural domestic water consumption should pay more attention to user lifestyles (water appliance usage habits, outdoor water use) and cultural backgrounds (age, education)
A framework approach for unravelling the impact of multiple factors influencing flooding
To have a better understanding of the influence of topographic, climatic, and, especially, anthropogenic factors on hydrological discharge and flooding, this study proposes a new framework approach using a set of methods to answer the questions why, where, when, and how flooding occurs. Including conditional inference tree (CIT), cross-correlation, and double-mass curves analysis, the approach is demonstrated in an application to the Wei River Basin, China. From the CIT analysis, dam construction period was identified as the most important factor (why), and the sub-catchment farthest upstream contributed the most to the flooding of the downstream floodplain (where). We then analysed the effect of the periods of dam construction on the time lag change (when) and the precipitation-discharge relationship (how) using cross-correlation analysis and double-mass curves analysis, respectively. The results suggested that the dam construction delayed the precipitation for 0.4days on average compared to before the dam construction period, and the discharge at the outlet of the basin was reduced by 44%. This framework approach is promising as it can quantitatively evaluate the importance of multiple factors on multiple years of flooding, while many studies evaluate single flooding events.</p
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