TIME DOMAIN SIMULATION FOR SOUND PROPAGATION OVER VARIOUS OBJECTS AND UNDER VORTICAL BACKGROUND CONDITIONS

Acoustic wave propagations have been studied for a long time with both experimental and numerical methods. Most of the analytical solutions for wave propagations are considered for simple environments such as a homogeneous atmospheres. As a result, the analytical solutions are unable to be applied for complicated environments. Numerical methods have become more and more important in acoustics studies after decades of development. The finite difference time-domain method (FDTD) is one of the most commonly used numerical methods in wave propagation studies. Compared with the other methods, the FDTD method is able to include many aspects of sound wave behaviors such as reflection, refraction, and diffraction in the physical problems. In this thesis, the linearized acoustic Euler equations coupled with the immersed boundary method are applied to investigate the sound wave propagation over complex environments. For the three-dimensional simulations of sound wave propagation in long distance, the moving domain method and parallel computing techniques are applied. Based on these approaches, the computational costs are significantly reduced and the simulation efficiency is greatly improved. When looking into the effects of high subsonic vortical flow, a high order WENO scheme is applied for the simulation. In this way the simulation stability can be achieved and the sound scattering of vortical flow can be studied. Then, the numerical scheme is applied to simulate an ultrasonic plane wave propagating through biological tissue. The linearized Euler acoustic equations coupled with the spatial fractional Laplacian operators are used for numerical simulations. The absorption and attenuation effects of the biological lossy media are successfully observed from the simulation results. Throughout this thesis, the simulation results are compared with either experimental measurements or analytical solutions so that the accuracy of the implemented numerical scheme is validated

Platelet indices in type 1 diabetes mellitus

Aim: We aimed to compare platelet counts (Plt), plateletcrit (PCT) and platelet distribution width (PDW) values of type 1 diabetes mellitus (T1DM) patients with those of healthy subjects. Methods: The records of 39 T1DM patients who were hospitalized between January 2016 and May 2018 were retrospectively analyzed. Control group consisted age and body mass index matched nondiabetic patients. Subjects having history of cardiovascular disease or any other systemic disease were excluded. Results: Compared to control group Plt (270±63 vs. 215±35 k/mm3), PCT (0.217±0.057 vs. 0.168±0.034 %) and PDW [17.4(16.2-20.4) vs. 17(12.5-19.4) %] were significantly higher in T1DM patients. Conclusion: Platelet indices which are common, simple and inexpensive hemogram parameters are increased T1DM patients

Comparison of eosinophil counts in patients with acute pulmonary embolism: Could it be a predictor factor?

Aim: To investigate whether there is a relationship between both massive and sub-massive pulmonary embolism (PE) and eosinophil counts in order to evaluate it as a predictor factor. Methods: This retrospective study included 108 patients (64 sub-massive and 44 massive) who received both tomographic and clinical diagnoses of pulmonary embolism, and 75 subjects served as controls. Hemogram parameters were compared between patients with massive and sub-massive pulmonary embolism and those of control groups.Results: In terms of white blood cell and eosinophil counts, the lowest value was evident in the massive PE group whereas the control group had the highest value. The eosinophil counts increased significantly one week after the treatment when compared to those at the presentation with PE (0.112 (0.003-0.853) vs. (0.144 (0.011-0.914), p=0.01). Spearman correlation test showed a significant positive correlation between right ventricular dysfunction or elevated cardiac troponin level and massive PE (r=0.54, p <0.001), whereas a negative correlation was detected between eosinophil count and the presence of massive PE (r=-0.36, p<0.001). Conclusion: The results of our study suggest that lower eosinophil counts may lead a physician to suggest a higher probability of acute massive pulmonary embolism rather than sub-massive pulmonary embolism. However, further randomized studies are required to confirm these findings

Early Maturation of Corpus Luteum in Rabbits - Effect of Sildenafil Citrate on Luteolytic Capacity in the Early Luteal Period

Background:  Prostaglandin F2 alpha (PGF2α) binds to the specific receptor (PTGFR) on the corpus luteum (CL) in mammals, inducing regression of the CL structure (luteolysis) and initiating a new cycle. While PGF2α is effective only on mature CL, the immature CL structure (early luteal phase) resists PGF2α. In this study, sildenafil citrate, which is used to increase blood flow in the genital organs for treating specific pregnancy issues in women, was administered during the early luteal phase in a rabbit model to test the hypothesis of enhancing blood flow to the CL, thereby promoting earlier maturation and enabling a response to PGF2α. Materials, Methods & Results: The study was conducted in 2 sub-studies: clinical and molecular. A large number of rabbits were initially included in the sub-studies to ensure a sufficient number of pseudo-pregnant rabbits. Ovulation in rabbits was induced with buserelin acetate and was considered as day 0 of the study. The sub-studies were continued with rabbits whose pseudo-pregnancies were confirmed according to progesterone (P4) results. As a result, the studies were continued with a total of 41 pseudo-pregnant New Zealand female rabbits, 21 of which were included in the clinical sub-study and 20 in the molecular sub-study. In both sub-studies, on day 3 of the luteal period, rabbits in the treatment group received 5 mg/kg sildenafil citrate and all rabbits received a single dose of exogenous PGF2α on day 4 to induce luteolysis. In the clinical sub-study, echotexture and intraovarian blood flow changes in the ovaries were determined by ultrasonography (USG) examination. In the molecular sub-study, the expression changes of Hypoxia Inducible Factor 1 Alpha (HIF1A) and Vascular Endothelial Growth Factor (VEGF) related to angiogenesis, Steroidogenic Acute Regulatory Protein (StAR) related to P4 metabolism, Prostaglandin-Endoperoxide Synthase 2 (PTGS2) related to prostaglandin (PG) mechanism and 15-Hydroxyprostaglandin Dehydrogenase (HPGD) genes at mRNA level were determined using Real Time Polymerase Chain Reaction (RT-PCR) in CL tissues obtained with ovariohysterectomy (OVH) at 1 and 12 h after PGF2α injection. In addition, blood samples were collected for determine P4 levels from all rabbits. In the clinical sub-study; there was no difference between the groups in mean gray values (MGV), whereas there was a significant decrease in both pulsatile index (PI) and resistance index (RI) values at 40 min after PGF2α injection (P < 0.05). In the molecular sub-study, it was determined that sildenafil citrate had no significant effect (P > 0.05) on the expression levels 1 and 12 h after PGF2α injection.  According to the results of the molecular sub-study, no significant effect of sildenafil citrate on the mRNA expression levels in the investigated genes was detected (P > 0.05). However, within each group, differences were found according to OVH time after PGF2α injection. It was observed that PTGS2 and HPGD mRNA expressions decreased at the 12th h compared to the 1st h, while HIF1A expression increased (P < 0.05). Discussion: According to the results obtained from clinical and molecular sub-studies, it was determined that a single dose of sildenafil citrate (5 mg/kg) applied on the 3rd day of the luteal period did not contribute to the maturation process of the CL, did not increase blood flow, and was insufficient to break the resistance of the CL against PGF2α applied on the 4th day of the luteal period. However, a significant decrease in the PI value at the 40th min after PGF2α injection suggests that sildenafil citrate has a supportive effect, and that this decrease is also seen in the RI value, suggesting that its effect is insufficient against the vasoconstrictive effect of PGF2α. Keywords: sildenafil citrate, PGF2 alpha, corpus luteum, early luteal stage, rabbit

Point-based and model-based geolocation analysis of airborne laser scanning data

Airborne laser scanning (ALS) is one of the most effective remote sensing technologies providing precise three-dimensional (3-D) dense point clouds. A large-size ALS digital surface model (DSM) covering the whole Istanbul province was analyzed by point-based and model-based comprehensive statistical approaches. Point-based analysis was performed using checkpoints on flat areas. Model-based approaches were implemented in two steps as strip to strip comparing overlapping ALS DSMs individually in three subareas and comparing the merged ALS DSMs with terrestrial laser scanning (TLS) DSMs in four other subareas. In the model-based approach, the standard deviation of height and normalized median absolute deviation were used as the accuracy indicators combined with the dependency of terrain inclination. The results demonstrate that terrain roughness has a strong impact on the vertical accuracy of ALS DSMs. From the relative horizontal shifts determined and partially improved by merging the overlapping strips and comparison of the ALS, and the TLS, data were found not to be negligible. The analysis of ALS DSM in relation to TLS DSM allowed us to determine the characteristics of the DSM in detail. © 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)

Fine-Scale Dissection of Functional Protein Network Organization by Statistical Network Analysis

Revealing organizational principles of biological networks is an important goal of systems biology. In this study, we sought to analyze the dynamic organizational principles within the protein interaction network by studying the characteristics of individual neighborhoods of proteins within the network based on their gene expression as well as protein-protein interaction patterns. By clustering proteins into distinct groups based on their neighborhood gene expression characteristics, we identify several significant trends in the dynamic organization of the protein interaction network. We show that proteins with distinct neighborhood gene expression characteristics are positioned in specific localities in the protein interaction network thereby playing specific roles in the dynamic network connectivity. Remarkably, our analysis reveals a neighborhood characteristic that corresponds to the most centrally located group of proteins within the network. Further, we show that the connectivity pattern displayed by this group is consistent with the notion of “rich club connectivity” in complex networks. Importantly, our findings are largely reproducible in networks constructed using independent and different datasets

Evaluation of epicardial fat tissue thickness in patients with multiple sclerosis

Aim: Multiple sclerosis (MS), which is inflammatory in its pathogenesis, damages the myelin sheath in the central nervous system (CNS) and causes axonal loss. Epicardial fat tissue (EFT), located between the myocardium and the visceral layer of the pericardium, surrounds the heart and several inflammatory cytokines is secreted from this tissue. In this study, we aimed to investigate EFT thickness in MS patients and compared with that of volunteer non-MS subjects. Methods: A total of 154 subjects comprising 61 MS patients and 93 volunteers matched for gender and age were included in our study.  Epicardial fat tissue thickness was measured by echocardiography. All values were compared between groups. Results: Echocardiographic parameters were similar in both groups. However, the mean EFT thickness was significantly higher in the MS group than in the control group (p<0.001). Epicardial fat tissue thickness was also significantly correlated with the presence of MS (r=0.33, p<0.001). Conclusion: The results of our study suggest that the increase in epicardial adipose tissue thickness in MS patients may be a predictive factor for cardiovascular disease. However, the clinical significance of this finding and its relevance to MS pathogenesis should be investigated in further studies

Evaluation of electrocardiographic ventricular repolarization parameters in stable coronary artery disease

Aim: To examine the relationship between the SYNTAX score (SS) and cardiac repolarization parameters such as cQTd and Tp-e values, and Tp-e/QT, Tp-e/JT, Tp-e/QTc, and Tp-e/JTc ratios in patients who have stable angina pectoris. Methods: 12-lead resting electrocardiograms (ECGs) and SS of 160 patients (51 female and 109 male) undergoing coronary angiography with the pre-diagnosis of stable angina pectoris were evaluated. Patients with a SS below 22 were classified as Group 1 (low-SYNTAX), and those above 22 (high-SYNTAX) as Group 2. Forty-four patients with normal coronary angiography were included in Group 3. Results: Mean age of the patients was 62.4±9.1 years. The heart rate, QRS, QT, cQT and JT durations between the groups were similar. In addition, relatively recent ventricular repolarization indices such as Tp-e interval and Tp-e/QT, Tp-e/JT, Tp-e/QTc, and Tp-e/JTc ratios were also not substantially different between groups. Conclusion: Several surface ECG predictors of ventricular arrhythmias, including QTd, JT and Tp-e intervals and their ratios to QT and JT, are not significantly correlated with SYNTAX score-assessed CAD severity in patients with stable angina pectoris

Effects of Rhizobacteria Application on Leaf and Fruit Nutrient Content of Different Apple Scion–Rootstock Combinations

The plant pomological characteristics and physiological behaviors of genotypes in modern apple cultivation could be different depending on the use of rootstock, changing growth ecology and application of biological control agents. The aim of this research was to determine the effects of rhizobacteria application on leaf and fruit nutrient contents in different apple scion–rootstock combinations. This study was carried out with seven standard cultivars (Scarlet Spur, Red Chief, Fuji, Jeromine, Galaxy Gala, Granny Smith, and Golden Reinders) budded on M.9 and MM.106 rootstocks. In the experiment, trees were sprayed by a nitrogen + phosphorus solvent rhizobacteria three times, with an interval of 15 days in the spring period. The effect of rhizobacteria application on leaf and fruit nutrient contents was statistically significant and provided generally significant positive contributions, except for leaf Mg content. Comparing both rootstocks, the positive effect of bacterial application was higher on the M.9 rootstock for leaf N and B content and fruit N and Fe content, and on the MM.106 rootstock for other nutrient content. While the effects of bacterial application on the basis of cultivars were generally positive, the highest positive contribution was made in leaf P content (10.7%) and fruit Mn content (32.1%) of the Fuji cultivar. Considering the total increase in nutrients in scion–rootstocks combination, rhizobacteria application had a positive effect on the leaf nutrient contents in Golden Reinders/MM.106, but not leaf K content. The highest increases in leaves of scion-rootstock combinations were determined as 4.0% in N content in Granny Smith/M.9, 14.1% in P content in Scarlet Spur/MM.106, 7.1% in K content in Fuji/MM.106, 4.4% in Ca content in Jeromine/M.9, and 14.0% in Mg content in Granny Smith/MM.106. The highest increase in fruit nutrient contents was between 4.9% (N content) and 13.5% (Ca content) for macro elements, and between 9.5% (Cu content) and 41.8% (Mn content) for microelements. The results of the present study may provide significant leads for further studies on this subject.Effects of Rhizobacteria Application on Leaf and Fruit Nutrient Content of Different Apple Scion–Rootstock CombinationspublishedVersio

Evaluation of electrocardiographic ventricular and atrial repolarization markers in patients with high grade varicocele

Aim: Varicocele is abnormal dilation of testis veins without unclear pathophysiology. Morphological studies showed imbalance between vasoconstrictor and vasodilator mechanisms. We aimed to determine the relationship between varicocele and cardiovascular system disorders with electrocardiography (ECG) parameters. Methods: This is a prospective study which was conducted in a University Hospital between February and June 2018. Thirty patients (18-45 years old) with high grade varicocele from urology outpatient clinic and 32 healthy volunteers for the control group were recruited to the study.  Results: P-min. value was significantly higher in control group than patients with high grade varicocele (p= 0.03). PR, QT and QTc intervals, PWD and P-max values were similar. Also, there were no significant differences in terms of the other ECG parameters between the groups. Conclusions: In this small prospective study we have found no association between high grade varicocele and potential electrocardiographic arrhythmia predictors namely OTd, QTc interval, PWD, Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio. Long-term follow-up and large-scale prospective studies are needed to confirm our results