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Influence on the thermoelectric characteristics of the growth parameters of BiSeTe thin films
No full textThis study systematically investigates the influence of magnetron sputtering parameters on the structural, electronic, and thermoelectric properties of 100 nm thick Bi2SexTe3-x thin films deposited on Si(100). The initial parameters for applied film deposition are used to set the x value. The films are fabricated with sputtering powers ranging from 30 to 100 W and pressures from 3 to 15 mTorr, with films grown under optimal conditions selected for post-deposition annealing at 523 K. A comprehensive characterization suite, including X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), and Kelvin probe force microscopy (KPFM), is used to establish direct correlations between processing, structure, and performance. XRD analysis reveals that increasing the sputtering pressure from 3 to 15 mTorr was critical for enhancing film crystallinity and promoting a strong (015) preferred orientation, while AFM showed a corresponding increase in average grain size from similar to 46 to similar to 60 nm via heat treatment (HT). EDS shows that films grown at 10 mTorr were almost certainly stoichiometric, but increasing the power to 15 mTorr caused tellurium deficiency. The films exhibited a power factor ranging from 2.5 to 2.8 mW m(- 1) K- 2 at 40 degrees C. HT improved the Seebeck coefficient from -115 mu V K- 1 to -140 mu V K- 1 and decreased the electrical resistivity by over 25 % through defect reduction and enhanced crystalline order. KPFM supported these findings, directly linking the crystallographic texture to the surface electronic structure and enhanced Seebeck effect
Distal radius morphometry of volar curvature along with scaphoid and lunate facet inclinations and ulnar variance in the Anatolian population
No full textThis study evaluates the morphometric characteristics of the volar distal radius, specifically volar curvature, scaphoid and lunate facet inclinations, and ulnar variance, in the Anatolian population. By identifying these population specific morphological variations, the study seeks to support improved anatomical compatibility of volar implants and enhance surgical planning for distal radius fracture fixation. Morphometric measurements were analyzed retrospectively on three-dimensional computed tomography images of 103 intact distal radii. Standardized sagittal sections were created through the midpoints of the scaphoid and lunate fossae, and volar curvature was quantified as the angle between the radial shaft axis and the volar cortex at 1 cm and 2 cm proximal to the distal radius volar rim on each section. Volar inclination angles were measured at 1 cm and 2 cm. Additionally, volar width (G), scaphoid facet inclination (SFI), lunate facet inclination (LFI), interfacet angle (IFA), and ulnar variance were evaluated. Volar curvature measured 1 cm and 2 cm proximal to the scaphoid and lunate fossae was significantly greater in males than females (p .05). The mean ulnar variance was − 2.0 ± 2.2 mm, while the mean LFI, SFI, and IFA were − 0.1° ± 8.4°, 26.1° ± 6.9°, and 24.2° ± 10.4°, respectively. This study demonstrates notable anatomical variations in the volar distal radius within the Anatolian population, particularly in volar curvature, scaphoid and lunate facet inclinations, and ulnar variance. These population specific morphometric differences underscore the importance of integrating multiple volar parameters into preoperative planning, as they may directly influence implant selection and improve the accuracy of distal radius fracture fixation
Çay Bahçesi Oluşturulması ve Bakım İşleri
No full textÇay tarımı 3. Hafta Ders Notu Konusu : Çay Bahçesi Oluşturulması ve Bakım İşler
The effect of the use of proton pump inhibitors (PPI) on complications in patients with cirrhosis
No full textBackground/aim: In our study, we aimed to investigate the effect of PPI use on peritonitis, and hepatic encephalopathy in patients with liver cirrhosis. Materials and methods: Our study was conducted on 220 patients. Patients with cirrhosis were divided into two groups PPI users and non-users. After the patients who did not use PPIs in their records were informed that they should not use PPIs in the future, both groups were followed up for three more years. 129 (58.6%) of the patients were PPI users and 91 (41.4%) of the patients were not PPI users. At the end of three years, these two groups were compared in terms of peritonitis. and encephalopathy. Results: The presence of encephalopathy was compared with PPI use status. Encephalopathy was present in 20 (16.2%) of PPI users, while 12 (13.2%) of non-PPI users had encephalopathy. No significant difference was found between the groups (p=0.230). When the presence of peritonitis in the patients was analyzed, peritonitis was found in 30 (23.7%) of the patients using PPIs, while 16 (17.6%) of the patients not using PPIs had peritonitis. There was no statistically significant difference between the groups (p=0.103). Conclusion: In our study, there was no statistically significant association between PPI use, peritonitis, and encephalopathy in patients with cirrhosis. It may be possible that this association may emerge in patients with decompensated cirrhosis and longer follow-up
The prevalence and correlates of arterial stiffness in patients with treated hypertension: oscillometric pulse wave analysis during 24-h ambulatory blood pressure monitoring
No full textBackground: We investigated the prevalence and correlates of arterial stiffness in treated hypertension using oscillometric pulse wave analysis during 24-h ambulatory blood pressure monitoring (ABPM). Methods: In this single-center cross-sectional study, 131 patients (median age 51.0 years, range 17.0–86.0; 54.2% female) underwent 24-h ABPM. Measurements included 24-h, daytime, and night-time SBP, DBP, MAP, pulse pressure, dipping status, and estimated pulse wave velocity (ePWV) derived by the Mobil-O-Graph (ARCSolver; age/SBP-dependent). Results: High ePWV (> 9 m/s) was present in 16.8% of patients. Compared with low/moderate ePWV, the high-ePWV subgroup was older (p < 0.001) and had higher FPG (p < 0.001), higher creatinine and lower eGFR (both p < 0.001), greater proteinuria (p = 0.006), and a lower frequency of systolic dipper status (p = 0.033). In simple correlations, 24-h ePWV was correlated positively with 24-h, daytime, and night-time values of DBP, MAP, and pulse pressure, BMI, FPG, creatinine, uric acid, and proteinuria, and negatively with systolic dipping, diastolic dipping, albumin, and eGFR. However, after adjusting for age, age2, and 24-h SBP, the partial correlation analysis revealed that ePWV was negatively correlated only with FPG (r = −0.216, p = 0.014) and hsCRP (r = −0.220, p = 0.031) and positively correlated only with total cholesterol (r = 0.243, p = 0.043) and LDL (r = 0.359, p = 0.004). Conclusion: Elevated ePWV identifies a high-risk phenotype in treated hypertension, characterized by advanced age and renal impairment. However, these associations appear intrinsic to the algorithm’s reliance on age and SBP. After adjusting for these inputs, ePWV did not exhibit independent associations with clinical parameters, suggesting it should be viewed as an integrated derivative of age and blood pressure rather than a separate physiological measure. ePWV values should be interpreted with caution, recognizing their inherent dependence on algorithmic inputs
Çayda Fidan Üretimi ( Vejetatif Çoğaltma)
No full textÇay Tarımı Dersi 5. Hafta Ders Notu Konusu : Çayda Fidan Üretimi ( Vejetatif Çoğaltma
Data Warehouses and Analytical Query Processing continue
No full textData Mining 5. Hafta Ders Notu Konusu : Data Warehouses and Analytical Query Processing
continu
Green tea mitigates the hallmarks of aging and age-related multisystem deterioration
No full textAging is characterized by progressive multisystem deterioration driven by molecular and cellular mechanisms encapsulated in the twelve hallmarks of aging. Green tea (GT), derived from Camellia sinensis, has garnered significant scientific interest due to its rich polyphenolic composition, particularly epigallocatechin-3gallate, and its pleiotropic health benefits. In this narrative review, we explored the multifaceted mechanisms through which GT may mitigate the aging hallmarks. Evidence from in vitro, animal, and human studies has shown that GT polyphenols can enhance DNA repair pathways, preserve telomere length, modulate epigenetic aging markers, improve proteostasis and autophagic flux, regulate nutrient-sensing networks, and rejuvenate mitochondrial function. Additionally, GT exhibits anti-inflammatory properties and may restore a physiological gut microbiota composition. Beyond molecular and cellular effects, GT consumption in humans has been associated with improved cognitive function, cardiovascular health, muscle preservation, and metabolic regulation in aging populations. Collectively, these findings highlight GT's potential as a naturally occurring geroscience intervention capable of addressing the interconnected network of aging processes more comprehensively than single-target pharmaceuticals. Future research should focus on optimizing dosing regimens, exploring synergies with other anti-aging strategies, and investigating personalized responses to GT interventions
HIV and pregnancy in türkiye: gaps and gains in the era of modern art: a multicenter cohort study
No full textWe aimed to review perinatal outcomes in HIV-positive pregnant women and their infants, as well as Turkish clinicians’ approaches to the management of HIV in pregnancy. This multicenter cohort study included pregnant women living with HIV (WLWH) across Türkiye from 2010 to 2024. 209 pregnancies among 162 WLWH were identified. Nearly 90.9% were diagnosed before or during pregnancy, and 90% were on antiretroviral therapy (ART) at delivery. 150 women had viral loads of less than 1,000 copies/mL during labor. The most chosen ART combination during pregnancy was tenofovir/emtricitabine+raltegravir. Most common mode of delivery was cesarean section (78.9%). Among 174 deliveries, 22 (12.6%) were preterm. Regarding newborn prophylaxis, 137 (88.4%) received zidovudine and 34 received nevirapine. 14 infants were breastfed. No congenital malformation, neonatal or maternal mortality was observed. Overall, 13 infants were diagnosed HIV-positive, indicating an MTCT rate of 7.9% in this cohort. Breastfeeding (OR: 30.1, 95% CI: 4.70-193.50, p <.001) and absence of ART during pregnancy (OR: 30.9, 95% CI: 5.20-183.90, p <.001) were the most prominent variables affecting the infants’ HIV positivity. Despite efficient preventative strategies announced over years, we report a high MTCT rate of 7.9%, aligning with previous literature from Türkiye. The findings highlight that the absence of ART and breastfeeding remain critical risk factors for perinatal HIV transmission. This large real-world cohort, reflecting Turkish clinicians’ practices, helps define major gaps in MTCT prevention in the modern ART era and provides valuable evidence to inform clinicians, policy makers, and public health strategies
Rapid maxillary expansion related sutural and dentoalveolar changes provoke early-term oxidative stress
No full textBackground: The management of oxidative stress-related cellular activity plays an important role in the bone healing process and dentoalveolar resorption. The aim of this study was to investigate the effects of rapid maxillary expansion on local and systemic oxidative stress levels. Methods: Thirty-five volunteer patients (17 females and 18 males) who needed rapid maxillary expansion were included in the study. Serum and unstimulated saliva samples were collected from each patient during four different periods: a week before the treatment (T0), the first day when sutural opening was detected clinically and radiographically (T1), the last day of the active expansion period (T2), and after the completion of a 3-month retention period (T3). To evaluate the patients’ periodontal status, plaque index, gingival index and probing pocket depth scores were recorded for each period. 8-hydroxydeoxyguanosine (8-OHdG), total oxidative status (TOS), total antioxidant status (TAS) and oxidative stress index (TOS/TAS: OSI) biomarkers were evaluated with ELISA and spectrophotometric methods to determine the local and systemic oxidative stress levels. Results: There were no statistically significant differences in the clinical periodontal parameters between the four measurement periods (p > 0.05). In the T1 period, only the salivary levels of the 8-OHdG (T1-T0; p:0.001, T2-T1; p:0.030, T3-T1; p:0.045), TOS (T1-T0; p 0.05). Conclusion: Periodontal and skeletal changes associated with rapid maxillary expansion cause an increase in only salivary oxidative stress levels, especially during the initial sutural opening period (5–7 days). Trial registration: Clinical Trial Number is NCT06937775. It was recorded retrospectively (Record date 21/04/25)