The Role of Horizontal Probe Drill Data in Tunnel Excavations: A Case Study from Istanbul Bosphorus Tunnel

Research methods are needed during excavations with TBM (Tunnel Boring Machine) to ensure safe excavation conditions because it is not possible to see and continuously monitor the excavation face completely. One of the most dangerous conditions expected in the tunnels that will be opened underwater is sudden and high water ingress. To detect possible water ingress, one of the most reliable methods that can be used is to perform horizontal probe drills. With water flow, the dimension of the danger increases more if weak ground conditions and fault and/or crush zones are monitored intensively. Such conditions may cause serious damage to TBM, and sudden washing can cause collapse and deviations in the vertical and horizontal axes. In this sense, considering the negativities of the geological and hydrogeological conditions of the Bosphorus Tunnel passing beneath the Bosphorus Strait, it was set as a contract condition that TBM excavation would be performed according to the results of the horizontal probe drills. During the excavation along the tunnel route, horizontal probe drills were performed at an average of 36 m. The Instantaneous Advance Speed (IAS) with 1-cm intervals, Thrust Pressure (TP), Torque (TQ), and washing water thrusts of the horizontal probe drills were recorded in this respect. In this article, the Instantaneous Advance Speed (IAS) values recorded during drilling were normalized with torque and thrust values, respectively. In this way, the changes in advance speeds were determined, and it was determined whether these changes were caused by increased thrusts, and/or torque or lithological changes. The relations between normalized Instantaneous Advance Speed (IAS) values and the RQD values at the tunnel excavation level of 14 vertical drillings built on the tunnel route were revealed. These relationships showed that the speed of Instantaneous Advance Speeds decreased as RQD values increased. This study must be proceeded by analyzing statistical data with a database containing more vertical drilling data to develop the TBM performance prediction model in such a way that the relations between formation characteristics and horizontal probe drill performance are revealed based on horizontal probe drill data

Novi lokaliteti nalaza stranih vrsta kozica Penaeus aztecus (Ives, 1891) i Metapenaeus affinis (H. Milne Edwards, 1837) u Egejskom moru

New findings about the distribution area of Penaeus aztecus and Metapenaeus affinis were reported with this study. Diagnostic features of the both species and some morphometric measures of the specimens were given. In addition, the recent occurrence map of these species in the Mediterranean Sea is provided.Novi nalazi kozica Penaeus aztecus i Metapenaeus affinis predstavljeni su u ovom radu, te su iznesene dijagnostičke značajke obje vrste i neka morfometrijska mjerenja uzoraka. Osim toga, prikazana je i nova mapa nalaza ovih vrsta u Mediteranu

Determination of Serum Adenosine Deaminase and Xanthine Oxidase Levels in Patients with Crimean–Congo Hemorrhagic Fever

OBJECTIVE: Crimean-Congo hemorrhagic fever is an acute viral hemorrhagic fever with a high mortality rate. Despite increasing knowledge about hemorrhagic fever viruses, little is known about the pathogenesis of Crimean-Congo hemorrhagic fever. In this study, we measured serum adenosine deaminase and xanthine oxidase levels in Crimean-Congo hemorrhagic fever patients. METHODS: Serum adenosine deaminase levels were measured with a sensitive colorimetric method described by Giusti and xanthine oxidase levels by the method of Worthington in 30 consecutive hospitalized patients (mean age 42.6 ± 21.0). Laboratory tests confirmed their diagnoses of Crimean-Congo hemorrhagic fever. Thirty-five subjects (mean age 42.9 ± 19.1) served as the control group. RESULTS: There was a significant difference in adenosine deaminase and xanthine oxidase levels between cases and controls (p<0.05). However, neither adenosine deaminase nor xanthine oxidase levels varied with the severity of disease in the cases assessed (p>0.05). CONCLUSION: Adenosine deaminase and xanthine oxidase levels were increased in patients with Crimean-Congo hemorrhagic fever. Elevated serum xanthine oxidase activity in patients with Crimean-Congo hemorrhagic fever may be associated with reactive oxygen species generated by the xanthine/xanthine oxidase system during inflammatory responses. In addition, elevated lipid peroxidation may contribute to cell damage and hemorrhage. The association of cell damage and hemorrhage with xanthine oxidase activity should be further investigated in large-scale studies

Short-term effects of transcatheter aortic valve implantation on left atrial appendage function

Background: The beneficial effects of the transcatheter aortic valve implantation (TAVI) on echocardiographic parameters including left atrial (LA) and left ventricular (LV) functions were described by previous studies. The aim of this study was to analyze the effects of TAVI on left atrial appendage (LAA) function assessed by transthoracic and transesophageal echocar­diography. Methods: Fifty-five patients with severe symptomatic aortic stenosis were included in this prospective study. LAA early and late emptying velocities, LAA filling velocity, peak early diastolic (EM), late diastolic (AM), and systolic (SM) velocities were measured with pulsed wave Doppler and tissue Doppler imaging, and E/Em ratio was calculated before and 7.1 ± 2.8 days after TAVI. A subgroup analysis was performed in accordance with the left ventricular ejection fraction (LVEF) of the patients and the severity of their LV diastolic dysfunction. Results: Although the post-procedure peaks and mean gradients of the patients decreased sig­nificantly, the LVEF increased significantly in those who had low LVEF before the procedure. The post-procedure E/Em ratio decreased significantly (p &lt; 0.001). The post-procedural LAA mean filling velocity and EM velocity were significantly higher than the pre-procedural filling velocity (p &lt; 0.001, p = 0.002, respectively). In the subgroup analysis, the post-procedural LAA filling velocity, early and late LAA emptying velocities, in addition to the mean velocity of the EM, AM, and SM were significantly higher than before the procedure in patients with LVEF of &lt; 50% and E/Em ratios of &gt; 15. Conclusions: LAA function improved soon after the TAVI procedure, especially in patients with low LVEF and marked LV diastolic dysfunction