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In this paper we inspect two mine detection algorithms [2,3], suggest modifications and present results on detection of anti-personnel (AP) landmines using methods employing Auto Regressive (AR) modeling algortihms. First method is based on the statistical distance between AR models of the reference and simulated data. In literature, while the statistical distance is calculated only for A-Scan data, in this study we suggest statistical distance to be calculated for both A-Scan and rows of the processed data. The second method is relied on AR modeling of the clutter energy in the B-scan. To decide whether a threat signature is present, it is proposed to utilize the difference between the estimated AR model clutter energy and the energy of real data. It is shown that proposed AR model based algorithms can be utilized to detect threat in GPR data and some advices to improve detection performance are given.

Data-driven approaches based on the data collected from individuals are improving everyday life as a result of the developments in big data studies. Prior to developing such an approach, removal of personal information from the data is important since personal information contained in data would jeopardize people's privacy and may harm related individuals. Especially in the field of health sciences, identifying personal information in the collected data is a difficult task as most of the data collected in hospitals are in plain text format. In this work, a method for automatically identifying words which includes personal information is proposed. The proposed method uses natural language processing techniques and bi-directional long short term memory networks. Development of the proposed method is done by using a de-identification challenge dataset which is composed of discharge summaries of 889 patients. The proposed method in this study is able to identify words that include personal information from their surrounding words without using dictionaries such as name lists or city lists. The tests at the end of this study show that proposed method can identify words containing personal information with an accuracy of 99.43%.

Cooled Versus Large-Tip Catheters for Flutter Ablation. introduction: Open cooled-tip and solid 8-mm-tip catheters have demonstrated safety and effectiveness for radiofrequency current (RFC) ablation of typical atrial flutter (AFL). However, data from prospective and randomized studies in this setting are lacking. Methods and Results: One hundred thirty consecutive patients (104 men; 61 ′ 11 years) with AFL were randomized to undergo RFC catheter ablation either using a solid 8-mm-tip catheter (group A, 65°C, 70 W, 60 s) or an open irrigated-tip catheter (group B, 65°C, 50 W, 60 s, 17 mL/min flow). Endpoint was bidirectional conduction isthmus block. In cases of repeated (two times) transient isthmus block; the catheter was changed (crossed over) to the catheter used in the other randomization arm, but patients remained in the original group following intention-to-treat analysis. The selected endpoint could be achieved in all patients after 12 ′ 6 RFC pulses in group A and 10 ′ 7 RFC pulses in group B (P = 0.11). Procedure times were longer (159 ′ 38 min vs 138 ′ 37 min, P = 0.002) and x-ray exposures higher in group A (fluoroscopy time 25 ′ 17 min vs 21 ′ 10 min, P = 0.08; x-ray dosage 3,133 ′ 2,576 cGy.cm 2 vs 2,326 ′ 1,405 cGy.cm 2 , P = 0.03). Transient isthmus block was observed in 23 group A patients and 12 group B patients (P = 0.03). Onset time of transient isthmus block ranged from 0.5 to 27 minutes. Repeated transient isthmus block occurred in 8 of the 23 patients in group A after 19 ′ 3 RFC applications. After crossover to the cooled-tip catheter, the endpoint was reached another 5 ′ 1 RFC pulses. In group B, all patients could be treated without change of ablation catheter. After a follow-up of 14 ′ 2 months, 2 patients (3%) in group A and 1 patient (1.5%) in group B presented with AFL recurrence. Conclusion: Open cooled-tip catheters are more effective than solid large-tip catheters for AFL ablation. The greater effectiveness is evident in cases showing repeated conduction recovery within the cavotricuspid isthmus. Primary use of open irrigated-tip catheters should be considered for AFL ablation.

Objective: Myeloperoxidase (MPO) has emerged as an important pathophysiological determinant of inflammatory vascular artery disease. It is appreciated that vessel immobilized, rather than circulating, MPO is critical for the progression of atherosclerotic lesions. The objective of this study was to investigate whether vessel-immobilized MPO is associated with the extent of coronary plaque burden. Methods: MPO plasma levels were determined by ELISA before and after heparin-release of vessel-bound MPO, to study the relation between vascular MPO deposition and densitometrically assessed coronary plaque burden in 77 patients with stable coronary artery disease. Results: Patients with a low increase in MPO plasma levels upon heparinization had a significantly smaller total plaque area and volume (12.1[IR:6.2e19.4]mm 2 vs. 19.8[IR:11.3e31.5]mm 2 , p < 0.01; 27.8 [IR:12.3e44.8]mm 3 vs. 55.2[IR:24.2e87.5]mm 3 , p < 0.05). Multivariable linear regression revealed that DMPO was independently associated with plaque area, and that DMPO increased with the number of affected vessels. Selective sampling confirmed the predominant role of coronary MPO deposition. Conclusion: Our data demonstrate that heparin-induced mobilization of vessel-bound MPO is closely linked to coronary plaque burden and thus further corroborate the evidence for the intimate involvement of this enzyme in vascular pathophysiology, as well as the importance of inflammation in atherosclerosis.

Navigation System for Ablation of Typical AFL. Introduction: Ensite® NavX (NavX) is a novel mapping and navigation system that allows visualization of conventional catheters for diagnostic and ablative purposes and uses them to create a three-dimensional (3D) geometry of the heart. NavX is particularly suitable for ablation procedures utilizing an anatomic approach, as in the setting of common-type atrial flutter (AFL). The aim of this study was to compare NavX-guided and conventional ablation procedures for AFL. Methods and Results: Forty consecutive patients (32 male, 59 ′ 12 years) with documented AFL were randomized to undergo fluoroscopy-guided (group I, 20 patients) or NavX-guided (group II, 20 patients) ablation, including 3D isthmus reconstruction. The same catheter setup was used in both groups. The endpoint of bidirectional isthmus block was obtained in all patients. Compared to conventional approaches, NavX-guided procedures significantly reduced fluoroscopy time (5.1 ′ 1.4 min vs 20 ′ 11 min, P < 0.01) and total x-ray exposure (5.1 ′ 3.1 Gycm 2 vs 24.9 ′ 1.6 Gycm 2 , P < 0.01). Isthmus geometry reconstruction could be performed in all patients of group II. In 4 patients (20%) of group II, anatomic isthmus variations were detected by NavX. No significant differences in radiofrequency current applications and procedural times were found between the two groups. Conclusion: NavX technology allows geometry reconstruction of the cavotricuspid isthmus. NavX-guided ablation of AFL reduces total x-ray exposure compared to the fluoroscopy-guided approach but does not prolong procedure time.