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Fluvial stratigraphy and palaeoenvironments in the Pasinler Basin, eastern Turkey
Valley floor sediments from the Pasinler Basin, eastern Turkey, provide evidence for Pleistocene and Holocene floodplain conditions. Three terrace surfaces are present. Evidence for tectonic processes active during the Late Neogene are widespread within the basin but do not appear to have substantially influenced the detail of the Holocene palaeoenvironmental record. Significant changes in hydrology are recorded, with more stable floodplain conditions occurring at around 9,000, 5,500 and 4,000 cal. yr. BP. Incision occurred sometime after approximately 4,000 BP, probably as a response to dual climatic and human controls. Comparisons with key sites in the Anatolian region and beyond suggest these changes are part of a regional climatic pattern, perhaps influenced by changes in the East African Monsoon. Differences in the details of the records across the region reflect the characteristics of the local environment, which, increasingly in the latter Holocene, includes human activity
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A new approach to planning in vitro and in vivo experiments for cardiovascular stents. (1) Fundamentals of design procedures
Copyright @ 2000 Pacini Editore SpAWhile the use of cardiovascular stents is internationally widespread re-stenosis remains a common problem. There are a number of different designs, and this project seeks for design improvements leading to a reduction in re-stenosis rates. The haemodynamics of the stent as used in a patient is viewed as one of the major concerns, and the authors have already applied Computational Fluid Dynamics in investigating this. In this more comprehensive study, however, the novel approach of applying two formal engineering design procedures is used, namely Genetic Algorithms (GA) and Robust Engineering Design (RED). In this paper, the two procedures are explained and compared in the context of their application to the design of stents
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A new approach to planning in vitro and in vivo experiments for cardiovascular stents. (2) Planning of experiments
Copyright @ 2000 Pacini Editore SpAWithin our overall project to improve the design of stents in terms of reduced rates of re-stenosis, there are three main methods, namely computer simulation and in vitro and in vivo experiments. These methods are closely integrated using contemporary design procedures described below, especially to accommodate patient-to-patient variation. Clinical experience shows that a small variation has considerable effects on flow characteristics of stents and in engineering terms may be described as a ‘geometric risk factor’. The Robust Engineering Design procedure readily incorporates this factor which may thus become a component feature in our experimental planning. We envisage that this approach could be applied to other invasive implants with a view to enhancing their quality
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Airborne observations of the tropospheric CO2 distribution and its controlling factors over the South Pacific Basin
Highly precise measurements of CO2 mixing ratios were recorded aboard both the NASA DC-8 and P3-B aircraft during the Pacific Exploratory Mission-Tropics conducted in August-October 1996. Data were obtained at altitudes ranging from 0.1 to 12 km over a large portion of the South Pacific Basin representing the most geographically extensive CO2 data set recorded in this region. These data along with CO2 surface measurements from the National Oceanic and Atmospheric Administration/Climate Monitoring and Diagnostics Laboratory (NOAA/CMDL) and the National Institute of Water and Atmospheric Research (NIWA) were examined to establish vertical and meridional gradients. The CO2 spatial distribution in the southern hemisphere appeared to be largely determined by interhemispheric transport as air masses with depleted CO2 levels characteristic of northern hemispheric air were frequently observed south of the Intertropical Convergence Zone. However, regional processes also played a role in modulating background concentrations. Comparisons of CO2 with other trace gases indicated that CO2 values were influenced by continental sources. Large scale plumes from biomass burning activities produced enhanced CO2 mixing ratios within the lower to midtroposphere over portions of the remote Pacific. An apparent CO2 source was observed in the NOAA/ CMDL surface data between 15° N and 15° S and in the lower altitude flight data between 8° N and 8.5° S with a zone of intensity from 6.5° N to 1° S. Inferred from these data is the presence of a Southern Ocean sink from south of 15° S having two distinct zones seasonally out of phase with one another. Copyright 1999 by the American Geophysical Union
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A new approach to planning in vitro and in vivo experiments for cardiovascular stents – II. Planning of experiment (abstract)
Within our overall project to improve the design of stents in terms of reduced rates of re-stenosis, there are three main methods, namely computer simulation and in vitro and in vivo experiments. These methods are closely integrated using contemporary design procedures described below, especially to accommodate patient-to-patient variation. Clinical experience shows that a small variation has considerable effects on flow characteristics of stents and in engineering terms may be described as a ‘geometric risk factor’. The Robust Engineering Design procedure readily incorporates this factor which may thus become a component feature in our experimental planning. We envisage that this approach could be applied to other invasive implants with a view to enhancing their quality
Geomorphological insight into changing tectonic regime, Pasinler Basin, Turkey
The Pasinler Basin, in the East Anatolian Contractional Province, features a suite of
geomorphological zones, visible in the field, air photographs and Landsat and SRTM
DEM imagery. These zones reflect past and current tectonically influenced processes.
Collins et al: Geomorphological insight into changing tectonic regime, Pasinler Basin, Turkey. 2 of 26
Remnants of the Erzurum-Kars plateau representing Mio-Pliocene volcanism,
associated with transtensional tectonics, have been modified by two stages of drainage
development: an earlier, shallow valley network, which was modified following uplift and
tilting to form the present system characterised by deep narrow valleys that supply
alluvial fan complexes. These fans discharge onto the present, aggradation-dominated
basin floor. Initial normal faulting induced massive slope failures on the basin’s northern
margin. This extensional phase within the basin was reversed by the Late Pleistocene,
with thrust faults modifying and producing landforms, and affecting sediment sequences,
along both the north and south basin margins. The shift from a transtensional regime
and associated volcanism to normal faulting in the Pliocene-Early Pleistocene, and then
to the present compression-dominated regime appears to correspond with regional
tectonic changes resulting from collision of the Arabian microplate and the subsequent
westward movement of the Anatolian microplate
The Development of Low Cost Sensor technology to provide Augmented Feedback for On-Water Rowing
Investigations to identify ways to improve stroke technique of rowers are on going (Anderson et al 2005). However, the majority of these studies are laboratory based and thus neglect the effects of the oar and water have on the rowing stroke. Traditionally on-water testing has tended to concentrate on the forces produced by the rower at the oar handle, foot stretcher and on boat by the rower but not the actual rowing technique (Hill, 2001). The purpose of this study was to design and develop a system that would provide quantitative feedback of the rowers’ technique on the water. This was accomplished through the integration of low cost electronic sensors, specific software interface and use of wireless technology (Anderson & Collins 2004)
Concussion in sport: what is known and what is new?
The aim of this article was to summarise the latest definition of concussion, signs of concussion, as well as important facts on recovery and graduated return to play, for different age groups. New technologies available to the sports physician are listed.Keywords: concussion, diagnosis, return to play, sign
A Comparison of Stride Length and Lower Extremity Kinematics during Barefoot and Shod Running in Well Trained Distance Runners
Stride length, hip, knee and ankle angles were compared during barefoot and shod running on a treadmill at two speeds. Nine well-trained (1500m time: 3min:59.80s ± 14.7 s) male (22 ±3 years; 73 ±9 kg; 1.79 ±0.4 m) middle distance (800 m – 5,000 m) runners performed 2 minutes of running at 3.05 m·s-1 and 4.72 m·s-1 on an treadmill. This approach allowed continuous measurement of lower extremity kinematic data and calculation of stride length. Statistical analysis using a 2X2 factorial ANOVA revealed speed to have a main effect on stride length and hip angle and footwear to have a main effect on hip angle. There was a significant speed*footwear interaction for knee and ankle angles. Compared to shod running at the lower speed (3.05 m·s-1), well trained runners have greater hip, knee and ankle angles when running barefoot. Runners undertake a high volume (~75%) of training at lower intensities and therefore knowledge of how barefoot running alters running kinematics at low and high speeds may be useful to the runner
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