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The Prevalence of Previous Coronavirus Disease-19 in Patients with Pulmonary Thromboembolism and Its Effect on Embolism Severity
No full textBackground/Objectives: The association between past coronavirus disease-19 (COVID-19) infection and pulmonary thromboembolism (PTE) is a potential research topic. We aimed to research the prevalence of previous COVID-19 infection in patients with PTE and to determine whether there is a difference in embolism severity in these cases. Methods: Study design: Multicenter, observational, cross-sectional. Patients diagnosed with PTE between 11 March 2022 and 11 March 2023 were prospectively included in this study, excluding cases with PTE along with active COVID-19, patients under the age of 18, and pregnant patients. Group 1 consisted of PTE cases with previous COVID-19, and Group 2 consisted of PTE cases without previous COVID-19. Key variables are D-Dimer level, right ventricle/left ventricle (RV/LV) ratio, simplified pulmonary embolism severity score, and treatment type. Results: A total of 1185 patients (Group 1; n = 360, Group 2; n = 825) were included in this study. The proportion of patients with RV/LV ratio > 1 on computed tomography pulmonary angiography (CTPA) was significantly high in Group 2 compared to Group 1 (27.9% vs. 19.7%, p = 0.003). In multivariate logistic regression analysis, the absence of any identifiable risk factor for PTE was found to be a 0.46-fold protective factor in the presence of previous COVID-19 (OR: 0.456 95% CI: 0.274–0.760, Wald = 9.070, df = 1, p = 0.003) and an RV/LV ratio > 1 on CTPA was found to be a 0.60-fold protective factor (OR: 0.603, 95% CI: 0.365–0.998, Wald = 3.874, df = 1, p = 0.049). Conclusions: The prevalence of previous COVID-19 infection in PTE cases was 30.4%, and 26.3% of idiopathic cases had previous COVID-19 infection. Although the parameters related to embolism severity were higher in the non-COVID-19 group, multivariate analyses revealed a 2.2-fold increased risk for idiopathic PTE and a 1.7-fold increased risk for RV/LV ratio > 1 on CTPA in patients without COVID-19 compared to those with prior COVID-19
Analysis of Incidental Thyroid Cancers in Surgically Treated Toxic Goiter Patients
No full textDifferentiated Thyroid Cancer (DTC) is the most common endocrine cancer and the frequency of DTC detection in histopathological examinations in thyroid surgeries performed for non-cancer indications is increasing. The aim of this study is to investigate the rate of incidentally detected thyroid cancer in patients who underwent surgery for toxic goiter in our clinic. Histopathological data of patients who underwent surgery with a diagnosis of toxic goiter were retrospectively reviewed. Patients were divided into 3 groups as toxic adenoma (TA), toxic multinodular goiter (MNG) and Basedow-Graves disease. The presence of malignancy and clinicopathological features were investigated RESULTS: 84% of the cases were female and 16% were male, and the mean age was 43. 202 (65%) of the toxic goiter cases had TMG, 8 (3%) had TA, and 101 (32%) had Graves' disease. Histopathologically, the malignant/benign ratio was 65 (21%)/ 246 (79%). Malignancy was detected in 3 of the 15 patients with a family history of thyroid cancer Incidental thyroid cancer was detected in 65 (21%) of the patients with toxic goiter. Thyroid carcinoma was present in 45 (22%) of the patients with toxic MNG, 1 (12.5%) of the patients with TA and 19 (19%) of the patients with Graves. Histopathological examination revealed 62 papillary (38 microcarcinoma), 2 Non-invasive Follicular Thyroid Neoplasm with Papillary-like Nuclear Features (NIFTP) and 1 medullary microcarcinoma. The incidence of incidental thyroid cancer in the patients with toxic goiter treated with surgery was found to be consistent with the literature
Investigation of the Effect on Thermal Performance Using Organic Phase Change Material in Battery Cooling Systems
No full textThe thermal performance of lithium-ion battery under passive cooling (organic PCM) is investigated experimentally. Coconut oil, soy wax and palm wax are used as organic PCM. This study investigates the temperatures at the anode, cathode and midpoint of the battery in natural convection and the effects of passive cooling method on three different organic PCMs located around Li-ion battery during different discharges (1C, 2C and 3C). The results with PCM are also compared with the cases without PCM and the effects of organic PCMs on battery thermal performance are determined. According to the experimental results, it is determined that at the highest discharge rate, coconut oil completely melted, palm wax is in mushy phase region and soy wax does not change phase. Depending on discharge rates, in the case without PCM, while the maximum battery surface temperatures range from 30.7 °C to 48.8 °C, these temperatures range from 25.5 °C to 42.6 °C for coconut oil, 24.8 °C to 41.8 °C for soy wax, and 25 °C to 40.5 °C for palm wax. Battery cooling performance is better in palm wax. In addition, when the surface temperatures of the battery are compared with organic PCMs temperature, it is identified that there is very little difference. These findings indicate that passive cooling can also reduce battery operating temperature and the use of organic PCMs can make positive contributions to battery thermal performance.</p
ARAS DAĞLARI’NIN BUZUL JEOMORFOLOJİSİ: YENİ BİR BUZULLAŞMA ALANI ZOR DAĞI’NDAN JEOMORFİK BULGULAR (DOĞU ANADOLU/IĞDIR-AĞRI)
No full textDoğu Anadolu Yüksek Platosu’nun doğusunda Küçük Kafkaslar’ın güneyinde bulunan Zor Dağı, Aras Dağları Volkanik Dağ Kuşağı dahilindeki en önemli stratovolkanik yükselimlerden biridir. Doğrultu atımlı fay sistemlerinin açılma çatlağı şeklinde karakter sergilemesiyle gelişen volkanizma, Zor Dağı yükseliminin morfojenezinden sorumlu temel yapısal süreçtir. Dağ, yükseltisi 3220 metreyi geçen iki zirveye sahiptir ve dağın iki krateri vardır. Bunların yanında Zor Dağı, kuzeyden Ararat güneyden ise Doğubeyazıt-Gürbulak havzalarını ayırmaktadır ve ayırdığı havzalar arasındaki konumundan dolayı batı sektörlü rüzgarlara cephe oluşturan bir morfografik uzanıma sahiptir. Dağa dair bu topoğrafik, jeomorfik ve morfografik özellikler dağın Geç Kuvaterner’de önemli buzullaşmalara sahne olmasını sağlamış ve bu çalışmayla dağlık alanın buzul jeomorfolojisi ilk defa ele alınmıştır. Özellikle K, KD ve D sektörlü yamaçlarda önemli buzullaşma alanları gelişen dağda toplamda yedi buzul vadisi ve yirmiiki sirk tespit edilmiş, buzul jeomorfolojisine dair bu yapıların çeşitli lokasyonlarında ise farklı jeomorfik dokuda morenler ve buzul çökelleri gözlemlenmiştir. Bölgesel atmosferik süreçlerin orografik zorlanmalarla yeniden şekillenmesi buzullaşmadan sorumlu ana parametrelerden birini oluştururken, krater morfolojisinin buzullaşma süreçleri üzerinde yönlendirici bir topoğrafik fenomen olduğu da görülmektedir. Yaklaşık olarak 27,21 km2 alan kaplayan buzullaşma alanında paleo-kalıcı kar sınırı 3 farklı metotla (AAR, AABR, MGE) hesaplanmış ve ortalama ~2538 m olarak belirlenmiştir. Bunun yanında buzul vadilerinde paleo buzul kalınlığı ~150 metreye kadar çıkarken, buzullaşmanın ~1900 metrelere kadar indiği tespit edilmiştir. Çalışmada buzul jeomorfolojisini ve yönlendiren süreçleri daha iyi yorumlama adına Arcmap Desktop 10.5 ve Saga 6.4.0. programları kullanılmış ve çeşitli haritalar (kırmızı rölyef, solar radyasyon değeri, topoğrafik açıklık indeksi, rüzgar etki indeksi, vadi derinlik oranı) üretilmiştir. Son Buzul Maksimumu’nda geliştiği düşünülen buzul jeomorfolojisine dair elde edilen tüm jeomorfik, kartoğrafik ve morfometrik veriler, Zor Dağı’nın Anadolu’da buzullaşmaya uğramış önemli volkanik yükselimlerden biri olduğunu göstermektedir.Anahtar KelimelerAras Dağları, Zor Dağı, Buzul Jeomorfolojisi, Buzul Vadisi</div
Molecular docking studies of hyrtiosin A and hyrtiosin B as inhibitors of PI3k/Akt/signaling pathway in cervical cancer
No full textImpact of Beneficial Microorganisms Inoculated Cotton Plants on Spodoptera exigua (Lepidoptera: Noctuidae)
No full textInvestigation of the Effect of CT-Relative Electron Density Curves on Radiotherapy Dose Calculation
No full textThe computerized tomography scanners play a significant role in the radiotherapy treatment planning process. The electron density obtained from the CT-RED curve can be used to determine the structure of materials, and TPS calculates the dose based on the material's composition. Errors in this curve can lead to inaccuracies in dose estimation, particularly in heterogeneous tissues. In this study, the effect of variations in the CT-RED curve on the radiation dose calculated with different algorithms was also investigated. A virtual phantom was created by the TPS system for five different environments, including two low-density (HU:−750 and HU:−300) and two high-density (HU:750 and HU:300) materials. Four different erroneous CT-RED curves were created, representing −5%, −10%, +5%, and + 10% deviations from the original CT-RED curve. The positive deviations are more prominent in regions with low HU values. On the other hand, negative errors tend to be more noticeable in regions with higher HU values. This indicates that changes in dose discrepancies are not proportional to the variations in HU. Since the HU values are converted to RED by the TPS, inconsistencies in HU values may lead to errors in the dose calculated by TPS. It is evident that errors in the CT-RED curve can affect the dose calculated by the TPS. However, it appears that this effect remains within acceptable limits. Given that different errors can combine to create significant differences, it is crucial not to overlook the importance of accurately transferring the CT-RED curve to the TPS
Akkaraman Erkek Kuzularda Sırt Görüntülerinden Dijital Görüntü İşleme ve Makine Öğrenmesi Yöntemleriyle Canlı Ağırlık Tahmini
No full textRetrospective Analysis of Demographic, Clinical, Biochemical, and Histopathological Findings of Gastrointestinal Polyps
No full textIntroduction: In this study, we aimed to demonstrate the histopathological, clinical, demographic, and biochemical features of upper and lower gastrointestinal (GI) tract polyps. Additionally, we aimed to investigate the effect of polyp localization on endoscopic intervention indications, polyp size, and biochemical, histopathological, and demographic characteristics. Materials and Methods: Endoscopic procedures performed in the endoscopy unit at the Van Yüzüncü Yıl University Dursun Odabaş Medicine Center between 2016-2021 were scanned. In total, 900 patients with polyps in the upper or lower GI tract were included in this study. Endoscopic procedure reports, biochemical data (C-reactive protein (CRP), sedimentation, hemoglobin, platelet, leukocyte, red cell distribution width, and ferritin values), histopathological data, endoscopic procedure indications, and demographic data of the patients were evaluated by statistical analysis. Results: Polyps were divided into three groups according to polyp size: dimunitive polyps 61.3% (n=552); small polyps 30.3% (n=273); and large polyps 8.3% (n=75). The polyps were also divided into three groups according to their histological features: noeplastic polyps (including; adenomatous polyps (38.3%), and serrated polyps (0.3%), malignant polyps (3.7%), and non-neoplastic polyps (57.2%). The incidence of adenomatous and malignant polyps was significantly higher in the left colon, whereas that of non-neoplastic polyps were significantly higher in the upper GI tract (p=0.001). The incidence of adenomatous polyps was significantly higher in large polyps (p=0.001). We determined the CRP and leukocyte values to be significantly higher in large polyps than in other polyp sizes (p=0.01, p=0.008, respectively). The platelet count was significantly higher in malignant polyps (p=0.026). Conclusion: This study revealed significantly higher leukocyte counts in polyps with lower GI tract and left colon localization. Additionally, higher platelet counts in polyps with malignant pathology and higher CRP levels and leukocyte counts in large polyps were detected
