9 research outputs found

    Change Detection Of Seafloor Topography By Modeling Multitemporal Multibeam Echosounder Measurements

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    The term "topography" implies the study of numerous landforms that exist on or below the Earth and a detailed knowledge of topography is required to understand the most Earth processes. In the oceans, sea floor topography refers the geographic features of the sea floor including the configuration of a surface and the position of its natural and man-made features; and detailed nautical charts are fundamental for many sciences such as physical oceanography, biology and marine geology. The hydrographic offices, which use the Multi Beam Echo sounder (MBE) system for the establishment of nautical charts, have their own set of accuracy standards for hydrographic surveys, which generally comply with the standards defined by the International Hydrographic Organization. MBE systems include multiple measurement systems such as sonar head, positioning system, motion sensor that work in a synchronized manner. Before the measurements, the "Patch Test" is required to eliminate the systematic errors due to instrumental synchronization and installation. In this test, signal delay test (latency), Y-axis rotation (roll), X-axis rotation (pitch), Z-axis rotation (yaw) errors are calculated. Besides, the effects of the sound velocity measurement through water column and the sea level changes need to be taken into consideration especially in the multi-temporal data analysis and 3D modeling. In this paper, the seafloor of the Anamur -TRNC Drinking Water Pipeline route in the "Northern Cyprus Water Project" is selected as a study area. This project, a unique in the world, is an international water diversion project designed to supply water for drinking and irrigation from southern Turkey to Northern Cyprus via pipeline under Mediterranean Sea. Multi temporal multi beam echo sounder measurements are used in the change analysis and surface modeling and the efficiency of this system is outlined together with its limitations

    Major neurocognitive disorder followıng isolated hippocampal ischemıc lesions

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    PubMed ID: 27825695Background and purpose Major cognitive disorder (MND) following vascular events is known as second causes of dementia after Alzheimer's disease (AD). Acute onset MND due to isolated hippocampal infarction has not been recognized as a specific subtype of vascular dementia, and there is no validated criteria for the identification of such cases, either clinically or radiologically. Results Among 7200 patients with first-ever ischemic stroke, 22 patients (0.3%) showed acute isolated ischemic lesions in the hippocampus. Four of them presented acute MND characterized by confusion at the beginning of stroke and thereafter they developed typical clinical characteristics of MND. These cases allowed us to delineate a specific type of dementia characterized by confusion at stroke onset, dull and aimless appearance, verbal and visual immediate or delayed memory deficits, dysexecutive syndrome. Major cognitive disorder was developed due to anterior involvement of the hippocampus with little interindividual variation. Stroke mechanism was artery-to-artery embolism or cardioembolism which can explain isolated infarcts of the hippocampus. Conclusions Hippocampal MND generally occurred in acute bilateral isolated hippocampal infarcts. The clinical characteristic of MND may be secondary to lesions of the body of the hippocampus and interruption of the hippocampo-temporal pathways and cortical projections. © 2016 Elsevier B.V

    Diffuse alveolar haemorrhage in children: an international multicentre study

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    Background Paediatric diffuse alveolar haemorrhage (DAH) is a rare heterogeneous condition with limited knowledge on clinical presentation, treatment and outcome. Methods A retrospective, descriptive multicentre follow-up study initiated from the European network for translational research in children’s and adult interstitial lung disease (Cost Action CA16125) and chILD-EU CRC (the European Research Collaboration for Children’s Interstitial Lung Disease). Inclusion criteria were DAH of any cause diagnosed before the age of 18 years. Results Data of 124 patients from 26 centres (15 counties) were submitted, of whom 117 patients fulfilled the inclusion criteria. Diagnoses were idiopathic pulmonary haemosiderosis (n=35), DAH associated with autoimmune features (n=20), systemic and collagen disorders (n=18), immuno-allergic conditions (n=10), other childhood interstitial lung diseases (chILD) (n=5), autoinflammatory diseases (n=3), DAH secondary to other conditions (n=21) and nonspecified DAH (n=5). Median (IQR) age at onset was 5 (2.0–12.9) years. Most frequent clinical presentations were anaemia (87%), haemoptysis (42%), dyspnoea (35%) and cough (32%). Respiratory symptoms were absent in 23%. The most frequent medical treatment was systemic corticosteroids (93%), hydroxychloroquine (35%) and azathioprine (27%). Overall mortality was 13%. Long-term data demonstrated persistent abnormal radiology and a limited improvement in lung function. Conclusions Paediatric DAH is highly heterogeneous regarding underlying causes and clinical presentation. The high mortality rate and number of patients with ongoing treatment years after onset of disease underline that DAH is a severe and often chronic condition. This large international study paves the way for further prospective clinical trials that will in the long term allow evidence-based treatment and follow-up recommendations to be determined. © The authors 2023
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