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Neuroprotective strategies during cardiac surgery with cardiopulmonary bypassSalameh, Aida, Dhein, Stefan, Dähnert, Ingo, Klein, Norbert 08 December 2016 (has links) (PDF)
Aortocoronary bypass or valve surgery usually require cardiac arrest using cardioplegic solutions. Although, in principle, in a number of cases beating heart surgery (so-called off-pump technique) is possible, aortic or valve surgery or correction of congenital heart diseases mostly require cardiopulmonary arrest. During this condition, the heart-lung machine also named cardiopulmonary bypass (CPB) has to take over the circulation. It is noteworthy that the invention of a machine bypassing the heart and lungs enabled complex cardiac operations, but possible negative effects of the CPB on other organs, especially the brain, cannot be neglected. Thus, neuroprotection during CPB is still a matter of great interest. In this review, we will describe the impact of CPB on the brain and focus on pharmacological and non-pharmacological strategies to protect the brain.
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Optimal Channel DesignAksoy, Bulent 01 September 2003 (has links) (PDF)
The optimum values for the section variables like channel side
slope,bottom width,depth and radius for triangular,rectangular,
trapezoidal and circular channels are computed by minimizing the cost
of the channel section.Manning &rsquo / s uniform flow formula is treated as a
constraint for the optimization model.The cost function is arranged to
include the cost of lining,cost of earthwork and the increment in the
cost of earthwork with the depth below the ground surface.The
optimum values of section variables are expressed as simple functions
of unit cost terms.Unique values of optimum section variables are
obtained for the case of minimum area or minimum wetted perimeter
problems.
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Geological Evolution Of The Gediz Graben, Sw Turkey: Temporal And Spatial Variation Of The GrabenCiftci, Bozkurt N 01 April 2007 (has links) (PDF)
Gediz Graben is a continental extensional basin filled with Neogene sediments. Its margins are controlled by active ~E& / #8211 / W-trending fault systems with major system, in terms of total offset and duration of activity, located along the southern margin. The graben evolved as a half graben by the activity of the southern margin during the entire Miocene. Then, the northern margin-bounding structure initiated by Plio& / #8211 / Quaternary to form the current configuration of the graben with an inherited asymmetry.
The southern margin-bounding fault system forms a graben-facing step-like pattern from the horst block (~2000 m) down to the graben floor (~200 m). The faults become younger towards the graben and the structural maturity decreases in the same direction. Fault plane data suggest ~N& / #8211 / S-oriented regional crustal extension through the entire graben history with no evidence of temporal change in the regional extension direction. Minor spatial variations are attributed to poorly defined s3-axis or local stress field anomalies caused by fault interactions.
Evolution of the Gediz Graben is a dynamic process as indicated by pronounced changes in the geometry and lateral extend of the southern margin-bounding structures along strike and dip directions. This also influenced the lithofacies, depositional pattern and thickness of the graben fill units. The western Anatolian extension is episodic with earlier (Miocene) and later (Plio& / #8211 / Quaternary) phases of extension and intervening short phase of contraction (Late Miocene& / #8211 / Early Pliocene). Despite of this fact, evidence for the short-term intervening contractional phase throughout the Gediz Graben is scarce and there is local observation of folds and thrust/reverse faults affecting the AlaSehir formation. These structures suggest that the short-term phase of contraction might have existed but most probably been absorbed by the high rates of extension. This data may further imply that graben evolution from half-graben phase (Miocene configuration) to full graben phase (present day configuration) might be a discontinuous process accompanied by a short-time break in-between.
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Optimization Of Multireservoir Systems By Genetic AlgorithmHincal, Onur 01 January 2008 (has links) (PDF)
Application of optimization techniques for determining the optimal operating policy for reservoirs is a major title in water resources planning and management. Genetic algorithms, ruled by evolution techniques, have become popular for solving
optimization problems in diversified fields of science. The main aim of this research was to explore the efficiency and effectiveness of the applicability of genetic algorithm in optimization of multi-reservoirs. A computer code has been constructed for this purpose and verified by means of a reference problem with a known global optimum. Three reservoirs in the Colorado River Storage Project were optimized for maximization of energy production. Besides, a real-time approach utilizing a blend of online and a posteriori data was proposed. The results achieved were compared to
the real operational data and genetic algorithms were found to be effective, competitive and can be utilized as an alternative technique to other traditional optimization techniques.
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Post-miocene Tectonic Evolution Of Alidag Anticline, Adiyaman, TurkeySeyrek, Emre 01 March 2005 (has links) (PDF)
Adiyaman region is situated within SE Anatolian Fold and Thrust Belt which is a
part of Alpine-Himalayan Mountain Belt system. The Belt is evolved as Eurasian
plate and Arabian plate amalgamates in SE Anatolia. There are two main
contractional deformational periods, Late Cretaceous and Late Miocene, which are
followed by a strike slip deformation, during post-Late Miocene characterizing the
tectonics of SE Anatolia.
Series of folds and thrusts have a trend of almost ENE-WSW direction. The analysis
on bedding planes and folds shows around N70E trend. On the other hand, two
overthrusts that are closely linked to the folds and a sinistral strike-slip fault with
reverse component are differentiated. The overthrust belt with ENE-WSW trend
bounds the study area from north with a vergence from north to south and situated on
top of folded upper Miocene sequences. Another overthrust and a cross-cutting strike
slip fault with reverse component &ndash / Adiyaman Fault- form a &ldquo / pop-up&rdquo / structure
(positive flower structure) which is characteristic for in a transpressional regimes
manifested in geological cross-sections done from borehole correlations and seismic
sections.
To conclude, by combining the surface (field data) and subsurface data (seismic and
borehole data), the Alidag anticlinal structure that is formed along the Adiyaman
Fault are developed after the Late Miocene under transpressional regime.
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Reproduction And Differentiation Strategies Of Upper-middle Class Group In AnkaraYaran, Pinar 01 January 2010 (has links) (PDF)
The main objective of this study is to investigate reproduction strategies of upper-middle class group of people in Ankara and their differentiation propensities in the fragmentation process of urban space. Dispositions and everyday life practices of upper-middle group on Bourdieu&rsquo / s approach in the urban space of Ankara are analyzed on the basis of intensive interviews with upper-middle class women. In this sense, special emphasis is placed on this group&rsquo / s close family relations, investment strategies in education, housing and living space strategies.
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Post-paleocene Deformation In Kalecik Region, East Of Ankara, TurkeyKasimoglu, Pinar 01 May 2010 (has links) (PDF)
In order to understand the tectonic evolution of the Kalecik region
(Ankara, Turkey), a structural field study was performed in a selected
area located in the east of Kalecik, where mostly imbricated thrust sheets
of the Cretaceous Ophiolitic melange crop out. In the study area, the
Cretaceous Ophiolitic melange, Cretaceous radiolaria-bearing sequences
and the Paleocene units are all intruded by sub-vertical dykes. The
attitudes of planar structures (dykes, beds and faults) and the kinematic
data measured on faults were analyzed by using &ldquo / ROCKWORKS 2002&rdquo / and &ldquo / Angelier Direct Inversion Method (version 5.42)&rdquo / softwares,
respectively.
A major trend of NE-SW (045° / N) direction and relatively a post-Paleocene
&ndash / pre-Miocene age was determined for the dykes indicating an extension
in the NW-SE direction during post-Paleocene. The dykes cut bedded
units displaying a dominant set trending in WNW-ESE (297° / N) direction
and mostly dipping towards NE with moderate dip amounts. But at the
same time, the Upper Cretaceous units were observed as intensely folded, faulted and thrusted due to the compressional regime that acted
in Central Anatolia during Late Cretaceous. The angular difference
between the major trend of dykes and the dominant trend of stratification
was found as approximately 108° / ., which may also indicate that the
dykes and beds were evolved during different deformation periods.
The results of the kinematic analyses of different age faults revealed that
the post-Paleocene &ndash / pre-Miocene Kalecik basaltic dykes are deformed
under a continuous NW-SE-oriented post-Paleocene compressional to
strike-slip tectonic regime which was followed by a NNW-SSE oriented
post-Miocene extensional-transtensional regime.
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Subsurface Structure Of The Central Thrace Basin From 3d Seismic Reflection DataTaikulakov, Yerlan Yengelsbekovich 01 January 2011 (has links) (PDF)
The Thrace Basin located in northwest Turkey displays attractive prospective traps for hydrocarbon and has received much attention from the petroleum industry. Despite the extensive exploration efforts, there are only few studies which address the fault kinematics and deformation mechanism of the
region in connection with structural development. In this study, 3D raw seismic data set collected around Temrez High near Babaeski fault zone will be processed and interpreted along with the available borehole data to reveal the subsurface structure of the region that will contribute towards understanding the Neogene tectonic evolution of the central Thrace basin, origin of the transcurrent tectonics and possible role of the North Anatolian Fault Zone.
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Maritime Accidents Forecast Model For BosphorusKucukosmanoglu, Alp 01 February 2012 (has links) (PDF)
A risk assessment model (MAcRisk) have been developed to forecast the probability
and the risk of maritime accidents on Bosphorus. Accident archives of
Undersecretariat Maritime Affairs Search and Rescue Department, weather
conditions data of Turkish State Meteorological Service and bathymetry and current
maps of Office of Navigation, Hydrography and Oceanography have been used to
prepare the model input and to forecast the accident probability. Accident data has
been compiled according to stated sub-regions on Bosphorus and event type of
accidents such as collision, grounding, capsizing, fire and other. All data that could
be obtained are used to clarify the relationship on accident reasons. An artificial
neural network model has been developed to forecast the maritime accidents in
Bosphorus.
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Identification Of Morphometric Properties Of Basins Located On Western Part Of NafzSarp, Gulcan 01 February 2012 (has links) (PDF)
This study aims to investigate tectonic activity levels and development stages of the
tectonic and hydrologic basin areas located on western part of the main trace of the
North Anatolian Fault Zone (NAFZ) using quantitative measurement techniques.
The basins investigated are Bolu, Yeniç / aga, Dö / rtdivan, Ç / erkes, Ilgaz and Tosya.
The methodology includes application of six morphometric indices (Basin Shape,
Hypsometric curve and Hypsometric Integral, Sinuosity of Mountain Fronts,
Stream Length Gradient Index, Valley width to height ratio, and Asymmetry
Factor) to Digital Elevation Model (DEM) of the region generated from 1:25000
scale topographic maps.
The analyses indicate that the basins located in the study area have different
characteristics of tectonic activity. According to the results of the applied indices
relative order of the activity for tectonic basins is, in decreasing order, Bolu, Tosya,
Ilgaz, Ç / erkes, Yeniç / aga and Dö / rtdivan. For hydrologic basins, on the other hand,
the same order is observed except for a swap in Ç / erkes and Yeniç / aga basins.
Among the basins located to the north of the NAFZ, the activity decreases eastward
whereas to the south the fault zone it decreases towards the west.
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