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High-speed cu-doped zns/n-si heterojunction photodiode for enhanced uv detection
No full textUltraviolet (UV) photodetectors are crucial for applications ranging from environmental monitoring to advanced optical systems. However, achieving both high sensitivity and fast response in the UV range remains challenging. We present a high-speed UV photodiode based on a Cu-doped ZnS thin film grown on n-Si by thermionic vacuum arc (TVA) deposition. Introducing Cu into ZnS significantly improved the film's crystallinity and induced p-type behavior in ZnS, forming a robust p-n heterojunction with the n-Si. The Cu-doped device exhibits enhanced optoelectronic performance, with a peak responsivity of approximately 149 mA/W (corresponding to an external quantum efficiency of similar to 49 %) under UV illumination, as well as rapid transient response characteristics (rise time similar to 6.6 mu s and fall time similar to 291 mu s). The-3 dB bandwidth reaches about 7 kHz, demonstrating significant highspeed performance. These performance metrics are competitive with the latest state-of-the-art UV photodetectors (see Table 5), highlighting the efficacy of Cu doping and TVA fabrication in advancing ZnS-based photodiodes. Overall, the ZnS:Cu/n-Si photodiode combines high sensitivity and speed, showing potential for future UV sensing technologies and integration into next-generation UV optoelectronic systems
Heart rate variability and blood lactate levels in elite swimmers after intensive interval spin loading: Effect of foam rolling on recovery
No full textBu araştırmanın temel amacı, elit yüzücülere yoğun interval sprint yüzme yüklenme sonrası uygulanan aktif dinlenmede foam rollingin, kalp hızı değişkenliği ve kan laktatı (üzerinde etkisini incelemektir. Araştırmaya, 15-26 yaş arasında toplam 15 (4 kız ve 11erkek) elit yüzücüleri gönüllü olarak katıldı (ortalama yaş 17.5±3.1 yıl, boy 178.2±7.6 cm, ağırlık 69.3±7.9 kg). Deneysel araştırma tasarımlarından “randomize-crossover” deseni ile gerçekleştirilen çalışmaya gönüllüler üç farklı oturumda ve birer hafta arayla uygulamalara katıldı. Birinci oturum alıştırma oturumu olarak tanımlandı. İkinci ve üçüncü oturumlarda ise ısınma, Pre-test, yüzme (50m), Test-1, yüzme (3x50m), Test-2, toparlanma ve Post-test gerçekleştirildi. Bu oturumlardan birisinde (FR) toparlanmada aktif dinlenme (750m düşük tempo yüzme; 10 dk) ve foam rolling (10dk) uygulandı. Diğer oturumda (NFR) ise sadece aktif dinlenme yapıldı (1500 m düşük tempo yüzme, 20 dk). Kalp Hızı Değişkenliği time domain (RR, RMSSD ve SDNN) ve frequence domain (VLF, LF ve HF) parametreleri Polar H7 V800 cihazı ile belirlendi. Kan Laktat ölçümleri el parmak ucundan Lactate Pro2 cihazı ile yapıldı. Elde edilen veriler, SPSS 29.0 for Windows istatistik programında Two Way ANOVA tekrarlanan ölçümler için varyans analiz testi [(2 uygulama x 4 zaman) kullanılarak analiz edildi. İkili karşılaştırmalar için Bonferroni testi kullanıldı. Foam Rolling ve Non Foam Rolling protokollerinde kendi içerisinde zamana bağlı olarak değişimlerde tüm Kalp Hızı Değişkenliği parametreleri ve Kan Laktatının toparlanmalar lehinde istatistiksel olarak anlamlı fark bulundu. Foam Rolling ve Non Foam Rolling protokolleri arasında RR (F=1.526; ɳ=.122), SDNN (F=1.197; ɳ=.325), RMSSD (F=.361; ɳ=.029), pNN50 (F=.579; ɳ= .460), VLF (F=.152; ɳ=.012), Kan Laktat (F=1.302; ɳ=.098) ve AZD (F=.704; ɳ=.055) değişimleri bakımından istatistiksel olarak anlamlı fark bulunmadı. Foam Rolling ve Non Foam Rolling protokolleri arasında LF (F=17.6; ɳ=.595) ve HF (F=2.43; ɳ=.169) değişimleri arasında istatistiksel olarak anlamlı fark bulundu. Sonuç olarak elit yüzücülere yoğun interval yüzme yüklenme sonrası uygulanan foam rolingin Kalp Hızı Değişkenliği ve Kan Laktat toparlanması üzerinde etkili olduğu söylenebilir.The main aim of present study was to examine the effect of foam rolling (FR) on heart rate variability (HRV) and blood lactate (BL) in elite swimmers after intensive interval sprint swimming load. A total of 15(4 female and 11 male )elite swimmers between the ages of 15 26 participated in the study voluntarily (mean age 17.5±3.1 years, height 178.2±7.6 cm, weight 69.3±7.9 kg). The volunteers participated in three different sessions, one week apart with a “randomized- crossover” method from experimental research designs. The first session was defined as the familiarization session. In the second and third sessions; warm-up, pre-test, swimming (50m), Test-1, swimming (3x50m), Test-2, recovery and post-test were performed. In one of these sessions (FR), active rest (750 m low tempo swimming; 10 min) and foam rolling (10 min) were applied during recovery. In the other session (NFR), only active rest was performed (1500 m low tempo swimming, 20 min). HRV time-domain (RR, RMSSD and SDNN) and frequency-domain (VLF, LF and HF) parameters were determined using a Polar H7 V800. Blood Lactate were taken from the fingertips with Lactate Pro2 device. The obtained data were analyzed using Two Way ANOVA repeated measures variance analysis test (2 experiment x 4 time) in SPSS 29.0 for Windows statistics program. Bonferroni test was used for pairwise comparisons. A statistically significant difference was found in favor of all Heart Rate Variability parameters and blood lactate recovery in the changes depending on time in Foam Roller and Non Foam Roller protocols. There were no significant differences between Foam Roller and NonFoam Roller protocols for RR (F=1.526; ɳ=.122), SDNN (F=1.197; ɳ =.325), RMSSD (F=.361; ɳ=.029), VLF (F=.152; ɳ=.012), Blood Lactate (F=1.302; ɳ=.098) and RPE (F=.704; ɳ=.055). Statistically significant differences were found between Foam Roller and Non Foam Roller protocols in terms of changes in LF (F=17.6; ɳ=.595) and HF (F=2.43; ɳ=.169). In conclusion, it can be said that foam rolling applied to elite swimmers after intensive interval swimming load during active recovery is effective on some time-domain parameters and frequency-parameters of Heart Rate Variability and Blood Lactate
Revisiting securitization theory within the context of north korea: A theoretical analysis of the success of trump's policy
No full textThis empirical study, grounded in securitization theory, questions whether the security utterances of former U.S. President Donald Trump on North Korea between January 20, 2017, and June 12, 2018, constituted only a securitizing move or evolved into a successful securitization practice. The research employs a hybrid methodology, combining discourse and content analyses supported by quantitative data. The focus is on analyzing the discourse within a corpus of 44 securitization statements made by the president. These statements were discerned through a comprehensive review of all the president's public remarks throughout the designated period, using queries such as "North Korea," "Democratic People's Republic ofKorea (DPRK)," "Kim Jong Un,"etc. Employing discourse analysis, the study reveals the referent objects and securitization arguments in these statements. The data gleaned from these statements is subsequently analyzed utilizing content analysis methodology. This study also evaluates the securitization discourse by examining its compliance with the facilitating conditions of an effective securitization rhetoric, a capable securitizer, and an audience-acceptable threat selection. Subsequently, it discusses the efficacy of the securitization discourse in terms of the two principal parameters proposed by the Copenhagen School: audience acceptance ofthe threat narrative contained in the securitizing moves, and the adoption of extraordinary measures
Real-world effectiveness and safety of sacituzumab govitecan in patients with metastatic or unresectable locally advanced triple-negative breast cancer: A multicenter study by the Turkish oncology group
No full textSacituzumab govitecan (SG) is an antibody-drug conjugate approved for metastatic or unresectable locally advanced triple-negative breast cancer (mTNBC) after at least two prior systemic therapies, yet real-world evidence remains limited. We conducted a retrospective, multicenter study including 285 patients with unresectable locally advanced or metastatic TNBC treated with SG across 52 oncology centers in Turkey. Median progression-free and overall survival were 5.4 months (95% confidence interval [CI], 4.6-6.2) and 12.2 months (95% CI, 10.5-13.9), respectively, with a 12-month overall survival rate of 49.2%. The objective response rate and disease control rate in evaluable patients were 36.8% and 63.9%. Grades 3-4 adverse events, mainly neutropenia, occurred in 44.2% of patients. Dose reductions were needed in 20% of cases; no treatment-related deaths were reported. Our large real-world cohort reinforces the effectiveness and manageable safety profile of SG, mirroring pivotal trials, and highlights its value as a therapeutic option in diverse and heavily pretreated mTNBC populations
A research on determining the effect of drought on fresh fruit and vegetables production : The example of Korkuteli district
No full textİklim değişikliği, uzun vadede sıcaklık ve yağış düzenlerinde gözlenen olumsuz yönlü sapmaları tanımlamak için kullanılan bir kavramdır. Küresel ölçekte olduğu gibi Türkiye’de de iklim değişikliğinin sonuçları açık biçimde hissedilmektedir. Ortalama ve ekstrem sıcaklıkların artması, yağış miktarında azalma olması yanında yağış şiddetinin artması iklim değişikliğinin hissedilen etkileridir. Yağış ve sıcaklık değerlerinden doğrudan etkilenen tarım sektörü, iklim değişikliğinin etkilerini en fazla hisseden sektörlerden birisidir. Bu çalışmada, Antalya ili Korkuteli ilçesinde gerçekleştirilen yaş sebze ve meyve üretiminde iklim değişikliğinin olası etkisi belirlenmeye çalışılmıştır. Öncelikle bölgedeki sıcaklık ve yağış miktarı değerlerinin yaklaşık son 50 yıl içerisindeki değişimi incelenmiştir. Yaş sebze ve meyve üreticilerinin iklim değişikliğine yönelik algılarını, risk değerlendirmelerini ve adaptasyon davranışlarını belirlemek içinde anket çalışması yapılmıştır. Bölgenin sıcaklık ve yağış değerlerinin incelenmesi sonucunda, ortalama sıcaklıkların artış eğiliminde olduğunu ve yağış rejimlerinde düzensizliklerin meydana geldiği belirlenmiştir. Yapılan anket çalışması sonuçlarına göre, üreticilerin büyük çoğunluğunun iklim değişikliğinden etkilendiği ve buna yönelik önlemler almak zorunda kaldıkları sonucuna ulaşılmıştır.Climate change refers to adverse changes in temperature and precipitation patterns. As is the case worldwide, the effects of climate change are also evident in our country. The increase in average and extreme temperatures, the decrease in precipitation amounts, and the increase in precipitation intensity are among the noticeable effects of climate change. The agricultural sector, which is directly affected by precipitation and temperature values, is one of the sectors most affected by climate change. In this study, the potential impact of climate change on fresh vegetable and fruit production in the Korkuteli district of Antalya province was investigated. First, the changes in temperature and rainfall amounts in the region over the past 50 years were examined. A survey was conducted to determine the perceptions of fresh vegetable and fruit producers regarding climate change, their risk assessments, and their adaptation behaviors. The analysis of temperature and precipitation values in the region revealed that average temperatures are increasing and irregularities are occurring in precipitation patterns. According to the results of the survey, it was concluded that the majority of producers are affected by climate change and are forced to take measures to address it
Evaluation of the relationships between beta-human chorionic gonadotropin (β-hcg) blood levels and pregnancy: A retrospective study
No full textObjective: To retrospectively evaluate the relationships between beta-human chorionic gonadotropin (beta-hCG) blood levels and pregnancy in primary care. Methods: The retrospective study was conducted in Bursa Uluda & gbreve; University Family Health Center in Turkey between October 1st and 31st October 2023. In the study, the data of pregnant women who applied to the Family Health Center for pregnancy examinations and follow-ups within the five years between January 1, 2018, and December 31, 2022, were taken from the database and evaluated retrospectively. History of current and previous pregnancies, sociodemographic findings, current diseases, allergies, cancer, genetic disease, Rh incompatibility, medication use, pregnancy risk factors, pregnancy complications, and delivery method and outcomes were obtained. Blood total beta-hCG measurement results were examined for pregnancy and differential diagnoses. P-values below 0.05 were considered statistically significant. Analyses were made in the SPSS 25.0 program. Results: The mean age of the 239 pregnant women who participated in the study was 28.74 +/- 4.02, and the mean total gestational age was 37.28 +/- 7.68 weeks. It was determined that 96.2% of the pregnant women had total beta-hCG levels in the blood above 5 mIU/ml. Risk factors were present in 26.4% of the pregnant women, and 3.8% of them developed complications during pregnancy. Blood beta-hCG levels were higher in those who had an additional disease during pregnancy, those who were on medication, those who had risk factors, and those who developed complications. While total beta-hCG measurement levels were lower in those who had normal or cesarean live births, they were higher in those who had abortions (p=0.03). Conclusion: In our study, blood beta-hCG levels were higher in pregnant women who had an additional disease, those who were on medication, those who had risk factors and those who developed complications. Total beta-hCG measurement levels were lower in those who had normal or cesarean live births, while they were higher in those who had abortions. Different results in blood beta-hCG levels require a holistic approach to evaluate pregnancy. In this critical process, the collaboration of family physicians with obstetrics, gynecology and other clinics is important
Effect of melatonin on growth performance in Saanen kids
No full textThis research was conducted to determine the growth performance of Saanen kids and to reveal the effects of maternal age, type of birth (single, twin or multiple), and sex on the properties of melatonin hormone to improve their growth performance. The research was carried out at Bursa Uludag University Research and Application Center of Veterinary Medicine. The animal material for the study consisted of 35 Saanen kids. Birth weight, 30th day, 60th day, 90th day, and 120th day live weights of Saanen kids were observed as 3.29 kg, 8.02 kg, 12.68 kg, 18.41 kg, and 21.26 kg, respectively. Birth weights were affected by maternal age and sex (P th day melatonin-treated and 60th day melatonin-treated groups and the control group showed no significant differences. The findings underscore the potential of melatonin as a growth-promoting agent in goat farming, aligning with previous research that has demonstrated its positive effects on growth trajectories in various livestock species. Moreover, maternal age was found to positively influence birth weights, while no significant differences were observed based on the birth type. These findings contribute valuable insights into optimizing growth strategies in goat husbandry, highlighting the need for further comprehensive studies to fully elucidate the mechanisms and long-term effects of melatonin supplementation on growth and development in Saanen goats
More than just sentiment: Using social, cognitive, and behavioral information of social media to predict stock markets with artificial intelligence and big data
No full textDigital transformation offers unprecedented opportunities to access data on hard-to-measure social aspects. In this digital era, social media platforms have become critical data sources for the social sciences. This study moves beyond traditional finance assumptions of "perfect information," "rational humans," and "isolated individuals" by analyzing retail investor behavior using Twitter data. It adopts a human model characterized by incomplete information, bounded rationality, and the influence of social and emotional factors. Tweets shared between January 1, 2012, and February 28, 2020, were collected. A GRU-based context classifier achieved 98% accuracy in identifying tweets related to Borsa Istanbul (BIST). Sentiment classification using a BERT model achieved 91% accuracy for positive and negative classes. Relationships between Twitter-obtained features and BIST indices were analyzed using machine learning methods such as linear regression, Lasso regression, random forest, and XGBoost. The analysis revealed that 91% of the change in the opening value, 63% of the change in trading volume, and 67% in volatility of the BIST 100 index could be attributed to cognitive, behavioral, and social features gleaned from tweets.National Center for High Performance Computing of Turkey (UHeM)
400765202
Optimized fopid controller for steam condenser system in power plants using the sinh-cosh optimizer
No full textSteam condensers in power plants are crucial for improving the efficiency of the power generation cycle by condensing and recycling steam from the turbine. We used fractional-order proportional-integral-derivative (FOPID) controller to regulate the pressure inside the steam condenser system. We adopted sinh-cosh optimizer (SCHO) to tune this controller. We analyzed the pressure fluctuations and transient responses to verify the system balance between different operational states. Several well-known algorithms, including the gravitational search algorithm, whale optimization algorithm, manta ray foraging optimization and aquila optimizer, are tested against the SCHO. The simulation demonstrates that the SCHO-based method outperforms other approaches in terms of integral of time-weighted absolute error (ITAE), normalized overshoot, and normalized settling time. The SCHO-based FOPID controller attained a minimal error of 14.80 for ITAE, a minimum percentage overshoot of 6.06%, and the shortest settling time of 17.66 s. The stated values confirm that SCHO-based FOPID controller offers superior and more consistent performance for the system under study. Nonlinear analyses further demonstrate the efficacy of the proposed method in terms of circulating water outlet temperature, cooling water flow rate, steam heat and condenser pressure
Interactions between the pathogenic fungus Cryptococcus neoformans and ants
No full textDespite the growing number of environmental surveys aimed to understand the ecology of the fungal pathogens Cryptococcus neoformans and Cryptococcus gattii, little is known about their relationships with arthropods. In the present study we collected a large number of samples from trees and arthropods living on them to determine the occurrence of Cryptococcus in arthropods, to understand if they could represent a vehicle for dispersion in the environment, and finally to investigate how they might interact with the fungus. Samples were collected from seven different geographical areas of the world: northwestern Italy, southeastern Italy, Slovenia, Kosovo, Greece, Turkey, and Colombia. A total of 1396 trees were examined and 11,805 samples were collected, including 7492 arthropod samples. Arthropod positive samples, mostly from ants, were found only in northwestern and southeastern Italy, Greece, and Slovenia with an average rate of 0.2%. Thirty-three of positive trees hosted positive arthropods whereas in six of them arthropods resulted negative. In addition, for six trees, positive samples from arthropods were not associated with positive arboreal samples. In vitro experiments showed that ants can transfer cryptococcal yeasts from a contaminated substrate (soil or bark) to a sterile one and that the fungus can survive inside the digestive apparatus of ants. The present study showed that ants are potential vehicles for C. neoformans although the frequency of which they enter in contact with the fungus is low. Cryptococcal yeasts can survive within the bodies of ants, but it remains unclear whether the relationship they establish with their host is parasitic, commensal, or symbiotic