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Utilization and importance of timing of therapeutic plasma exchange in kidney transplantation: A single-center experience
No full textIntroduction: Therapeutic plasma exchange (TPE) is a prominent approach for specific conditions among renal transplant candidates and recipients. The indications of TPE, those related to kidney transplantation, are limited, and knowledge and utilization strategies are blurred. Herein, we aimed to review our clinical experience of TPE among renal transplant recipients. Methods: A total of 69 (40.22 +/- 12.29 years, 40 males, 63.8% deceased donor) ABO blood type-compatible kidney transplant recipients who underwent TPE were evaluated between January 2013 and December 2019. Results: A median of 5 (IQR 4-7) TPE sessions was administered at a median duration of 31 (IQR 3-564) days after transplantation. The main indication was a rejection episode. A total of 61 (39.44 +/- 12.22 years, 24 living donor, 10 re-transplant, 37 male) recipients were successfully discharged with a serum creatinine of 1.39 (IQR 1-1.91) mg/dL, and eGFR of 62 (IQR 39-94) ml/min. Comparing the recipients according to TPE timing, early administered 32 (52.5%) recipients with a median of 4 (IQR 4-7) days after transplantation had better graft survival (62.5% vs. 17.2%, p < 0.001), despite higher mortality rates (25% vs.10%, p < 0.001). The rate of graft loss was higher (62.1% vs. 9.4%, p < 0.001) among the recipients who required TPE during the late post-transplant period (756 [IQR 272-1307] days). Conclusion: According to our findings, TPE could provide beneficial effects on graft and patient outcomes, and the timing of TPE could influence its efficiency. Further studies are needed to support our findings
Investıgation of speed control of an electric vehicle using PID and model reference adaptive control methods
No full textBu çalışmada, bir elektrikli aracın hız kontrolü farklı sürüş çevrimleri ve çevresel koşullar altında incelenmiştir. Taşıtın doğrusal hareketi için dinamik denklemler oluşturulmuş ve Nissan Leaf modelinin yapısal özellikleri ile motorun devir-moment karakteristik eğrisi dikkate alınmıştır. Batarya modeli olarak yaygın kullanılan Rint modeli tercih edilmiştir WLTP, NEDC ve FTP-75 sürüş çevrimleri hız-zaman girdisi olarak sisteme uygulanmış, her bir çevrimle aracın tepkileri değerlendirilmiştir. Hız kontrolü için ilk önce klasik PID (Oransal–Türev–İntegral) kontrol algoritması kullanılmış, parametreler çevrim takibini en iyi şekilde sağlayacak biçimde optimize edilmiştir. Gerçek yol eğimi ve rüzgâr koşulları gibi çevresel etkiler modele dahil edilerek sistemin gerçekçi sürüş senaryolarında da değerlendirilmesi sağlanmıştır. Çevre şartlarının değişimine göre hız, güç tüketimi, batarya kapasitesi ve şarj durumu üzerindeki etkiler analiz edilmiştir. Elde edilen sonuçlardan PID denetleyicinin farklı çevre şartlarında sürüş çevrimlerini yüksek doğrulukla takip edebildiğini göstermektedir. İkinci olarak model referans adaptif kontrol (MRAC) algoritması kullanılarak sistem aynı şartlar altında çalıştırılmış ve özellikle hız takibi ve batarya şarj durumu açısından PID 'ye göre daha başarılı sonuçlar verdiği gözlemlenmiştir. Bu sayede, elektrikli araçlarda denetleyici seçimlerinin enerji verimliliği üzerindeki etkisi de ortaya konmuştur Benzetim çalışmaları MATLAB/Simulink ortamında gerçekleştirilmiştir.In this study, the speed control of an electric vehicle was examined under different driving cycles and environmental conditions. Dynamic equations for the vehicle’s linear motion were derived, considering the structural characteristics of the Nissan Leaf model and the motor's speed-torque characteristic curve. The widely used Rint model was chosen for the battery. WLTP, NEDC, and FTP-75 standard driving cycles were applied as speed-time inputs to the system, allowing the vehicle’s responses to each cycle to be evaluated. A PID (Proportional–Integral–Derivative) control algorithm was used for speed control, and its parameters were optimized to ensure accurate tracking of the driving cycles. Additionally, environmental factors such as road gradient and wind conditions were included in the model to assess the vehicle's behavior under realistic driving scenarios. The vehicle was simulated on roads with varying slopes and wind influences, and the effects on speed, power consumption, battery capacity, and state of charge (SOC) were analyzed. The results demonstrated that the PID controller could accurately follow the desired driving cycles under different environmental conditions. Furthermore, a Model Reference Adaptive Control (MRAC) algorithm was also implemented and showed better performance than the PID controller, particularly in terms of speed tracking and battery SOC. Thus, the study highlighted the impact of controller selection on energy efficiency in electric vehicles. Simulations were conducted in the MATLAB/Simulink environment
Betulinic acid isolated from induces apoptosis and reduces the mTOR/PI3K/AKT signaling pathway in endometrial cancer cells.
No full textEndometrial cancer is one of the most common gynecological cancers worldwide, and an average of 42,000 women die each year. Chemotherapy, radiotherapy, and surgery are among the treatments available for endometrial cancer. Currently, drugs used for chemotherapy have had limited success in increasing the cure rate. Betulinic acid, a lupane-type triterpene widely found in the plant kingdom, has attracted attention for cancer treatment in recent years due to its ability to inhibit tumor growth and induce cell apoptosis. The aim of this study is to investigate the mTOR pathway-mediated anticancer effects of betulinic acid in human endometrial cancer cells. The effect of betulinic acid on Ishikawa cell viability was determined by the CCK-8 method. Its effect on the expression of genes involved in apoptosis and the mTOR pathway was assessed by real-time PCR. The effect on protein expression in the mTOR pathway was evaluated with immunohistochemistry and western blot, and the effects on apoptosis via Annexin V. Betulinic acid reduced Ishikawa endometrial cancer cell proliferation. Betulinic acid administration caused a significant decrease in Bcl2 (=0.008) expression and increased caspase-8 (=0.001) expression in Ishikawa cells. The results of Annexin V supported the idea that betulinic acid administration triggered apoptosis in Ishikawa cells. The mean rate of apoptotic cells in the betulinic acid group was 22±3.23%, while it was 2.31±0.2% in the control group (=0.02). Betulinic acid caused a significant decrease in the expression of AKT1 (=0.0001) and a significant increase in the expression of RAPTOR (=0.00002). Betulinic acid administration also significantly decreased protein expression in the mTOR pathway. The percentage of p-PI3K, p-AKT, and p-mTOR-positive cells in Ishikawa cells was 89.39±5.19%, 74.84%±5.07, and 82.02%±6.14, respectively, in the control group. In the betulinic acid group, these values were 49.12±19.12% (=0.002), 44.46±7.39% (<0.001), and 53.70±8.94% (<0.001), respectively. This study showed that betulinic acid decreased Ishikawa cell proliferation, triggered apoptosis, and decreased mTOR signaling; thus, betulinic acid may be a potential anticancer agent for the treatment of endometrial cancer
A city of women between two lips: Écriture féminine in Christine De Pizan and Luce Irigaray
No full textBu çalışma, Christine de Pizan’ın edebi üretimini Irigaray’ın dişil yazı anlayışıyla kesiştirerek de Pizan’da kadın öznenin yazı aracılığıyla nasıl yeniden kurulduğunu araştırmaktadır. Bu bağlamda Avrupa’nın ilk profesyonel kadın yazarı olarak kabul edilen De Pizan’ın, kadın özneyi yazı aracılığıyla nasıl yeniden kurduğu, Le Livre de la Cité des Dames (Kadınlar Kenti) ve Le Livre de la Mutation de Fortune (Talihin Değişimi) adlı eserleri üzerinden incelenerek De Pizan’ın metinlerindeki bedensel dönüşüm anlatıları, Irigaray’ın iki dudak, iç ile dış ve dişil yazı gibi kavramlarıyla birlikte okunarak, bu dönüşümlerin yalnızca fiziksel değil, dilsel ve metaforik geçişler olarak işlediği ortaya konmuştur.This study explores how the female subject is reconstructed through writing in Christine de Pizan’s literary production by intersecting her work with Luce Irigaray’s écriture feminine. In this context, De Pizan, who is recognized as the first professional female author in Europe, is examined through her works Le Livre de la Cité des Dames (The Book of the City of Ladies) and Le Livre de la Mutation de Fortune (The Book of the Transformation of Fortune), focusing on how she reclaims and reconfigures the female subject through writing. The narratives of bodily transformation in de Pizan’s texts are analyzed alongside Irigaray’s concepts such as “the two lips”, the inside-outside, and feminine writing, revealing that these transformations function not merely as physical but as linguistic and metaphorical
Non-suicidal self-injury in depressed adolescents: A social-cognitive deficit or an emotional response?
No full textObjective: Non-suicidal self-injury (NSSI) has been identified as a prevalent behavior among adolescents, particularly those with major depressive disorder (MDD). The present study sought to examine differences in neurocognition, social cognition, negative urgency (NU)-the tendency to act impulsively in response to negative emotions-and anxiety among adolescents with MDD and NSSI, MDD without NSSI, and healthy controls. Method: A total of 204 adolescents (aged 11-17 years; 161 girls [78.9%], 43 boys [21.1%]) were divided into three groups: (1) MDD with NSSI, (2) MDD without NSSI, and (3) healthy controls. Participants completed psychiatric assessments, computerized neurocognitive tests, emotion recognition tasks, and self-report measures of NU and anxiety. Data were analyzed using SPSS 22. Descriptive statistics included frequencies for categorical variables and medians for continuous variables. Group comparisons were performed using chi-square-based tests and the Kruskal-Wallis test. Logistic regression identified predictors of NSSI, with significance set at p < .05. Results: Adolescents with MDD exhibited significant deficits in executive function and episodic memory, as well as elevated NU and anxiety, compared to healthy controls. Furthermore, adolescents with MDD and NSSI reported significantly higher levels of anxiety (particularly panic symptoms) and NU compared to those with MDD alone. Conclusion: These findings suggest that emotional difficulties, particularly impulsivity and panic symptoms, play a crucial role in NSSI among adolescents with MDD rather than cognitive disturbance, highlighting potential targets for prevention and intervention efforts
Oncological safety of ıntrauterine manipulator use in laparoscopic hysterectomy for endometrial cancer: Apropensity score-matched analysis
No full textBackground and Objectives: Minimally invasive surgery is considered the standard of care for early-stage endometrial cancer. However, the oncological safety of intrauterine manipulator (IUM) use during laparoscopic hysterectomy remains controversial. The aim of this study was to evaluate the impact of intrauterine manipulator use during laparoscopic hysterectomy on oncological outcomes in patients with clinically early-stage endometrial cancer. Materials and Methods: In this retrospective cohort study, 612 patients with FIGO 2009 stage I–III endometrial cancer who underwent staging surgery at a tertiary center between January 2010 and May 2025 were included. Clinical and pathological characteristics were compared between laparoscopy (n = 168) and laparotomy (n = 444). To reduce selection bias, propensity score matching (PSM) was performed based on age, histological subtype, and FIGO stage. Kaplan–Meier survival analysis and Cox regression modeling were utilized to evaluate disease-free survival (DFS) and overall survival (OS). Results: After matching, groups were balanced except for higher rates of para-aortic lymphadenectomy and adjuvant therapy in the laparotomy group. IUM use was not associated with increased LVSI or positive peritoneal cytology. Recurrence was more frequent after laparoscopy (10.1% vs. 6.0%, p = 0.028), with inferior 5-year DFS (87.6% vs. 97.4%, HR 5.60, p = 0.0006), while OS was similar (82.0% vs. 87.6%, p = 0.842). In multivariate Cox analysis, independent predictors of worse DFS were non-endometrioid histology (HR 3.57), FIGO stage III (HR 3.06), grade 3 tumors (HR 2.63), and laparoscopic surgery (HR 0.51). For OS, non-endometrioid histology (HR 5.12), stage III disease (HR 2.98), and grade 3 tumors (HR 4.51) were independent adverse factors, whereas surgical approach was not. Conclusions: The use of an intrauterine manipulator in laparoscopic hysterectomy for early-stage endometrial cancer was linked to worse DFS but not OS. These findings suggest caution regarding the routine use of IUMs and highlight the need for prospective randomized trials to clarify their oncological safety
Fabrication of a symmetrical supercapacitor based on electrochemically interconnected Cu:NİO@rGO:PANI/NF electrodes
No full textBakır katkılı nikel oksit ve indirgenmiş grafen oksit katkılı polianilinden oluşan bir nanokompozit elektrot sentezlemek için üç-elektrotlu bir elektrodepozisyon hücresi kullanılmıştır. XRD, FTIR ve XPS gibi karakterizasyon teknikleri, moleküler bağların oluşumunu ve sentezlenen bileşiklerin fazlarını doğrulamak için kullanılmıştır. Enerji dağılımlı X-ışınları spektroskopisi (EDS) analizi, rGO:PANI/NF elektrodunun %0,29 azot (N), %17,39 karbon (C) ve %9,81 oksijen (O) içerdiğini, Cu:NiO@rGO:PANI/NF elektrodunun ise %8,24 bakır (Cu), %9,22 karbon (C), %7,21 oksijen (O) ve %0,72 azot (N) içerdiğini göstermiştir. Hem rGO:PANI/NF hem de Cu:NiO@rGO:PANI/NF elektrotlarının elektrokimyasal özellikleri, 3 M KOH sulu elektrolit kullanılarak üçelektrotlu bir hücre konfigürasyonunda değerlendirilmiştir. rGO:PANI/NF ve Cu:NiO@rGO:PANI/NF elektrotları için 20 Ag-1 akım yoğunluğunda sırasıyla 644,5 ve 807,1 Fg-1 ’lik önemli spesifik kapasitans değerleri elde edilmiştir. Cu:NiO@rGO:PANI/NF elektrodu (RCT = 0,9 Ω), rGO:PANI/NF elektrodundan (RCT = 3,8 Ω) önemli ölçüde daha düşük bir yük transfer direnci sergilemiştir, bu da NiO’in rGO ve PANI arasındaki yük transferini artırmada önemli bir rol oynadığını göstermektedir. Ayrıca, Cu:NiO@rGO:PANI/NF’un artan BET yüzey alanı, NiO ile birlikte iyi bağlanmış PANI zincirleri ağının bir sonucudur. Daha ileri uygulamaları keşfetmek için, Cu:NiO@rGO:PANI/NF elektrotları kullanılarak tamamen katıhal simetrik süperkapasitör (SSC) cihazı üretilmiştir. Bu cihaz 0 ila 1,5 V voltaj aralığında çalışmaktadır, 4,5 Ag-1 ’de 81,9 Fg-1 kapasitans göstermektedir ve 10000 şarj-deşarj döngüsünden sonra 10 Ag-1 ’lik belirli bir akımda %97,6 kapasitans tutma özelliğine sahiptir. Simetrik süperkapasitör, 4,5 A g-1 ’de 1297,6 W kg-1 güç yoğunluğunda 25,6 Wh kg-1 maksimum enerji yoğunluğuna ulaşmıştır. Bu bulgular göz önüne alındığında, nanokompozit bazlı katıhal süperkapasitör, yüksek performanslı simetrik süperkapasitörler oluşturmak için umut verici bir seçenek sunmaktadır.A three-step electrodeposition cell was utilized to synthesize a nanocomposite electrode consisting of copper-doped nickel oxide and reduced graphene oxide-doped polyaniline. Characterization techniques such as XRD, FTIR, and XPS were conducted to confirm the formation of molecular bonds and the phases of the synthesized materials. Energy dispersive X-rays spectroscopy (EDS) analysis revealed that the rGO:PANI/NF electrode comprises 0.29% nitrogen (N), 17.39% carbon (C), and 9.81% oxygen (O), whereas the Cu:NiO@rGO:PANI/NF electrode contains 8.24% copper (Cu), 9.22% carbon (C), 7.21% oxygen (O), and 0.72% nitrogen (N). The electrochemical properties of both rGO:PANI/NF and Cu:NiO@rGO:PANI/NF electrodes were evaluated in a three-electrode cell configuration using a 3 M KOH aqueous electrolyte. Remarkable specific capacitances of 644.5 and 807.1 Fg−1 were achieved at a current density of 20 Ag−1 for the rGO:PANI/NF and Cu:NiO@rGO:PANI/NF electrodes, respectively. The Cu:NiO@rGO:PANI/NF electrode exhibited a significantly lower charge transfer resistance (RCT = 0.9 Ω) than the rGO:PANI/NF electrode (RCT = 3.8 Ω), indicating that NiO plays a significant role in enhancing charge transport between rGO and PANI. Additionally, the increased BET surface area of Cu:NiO@rGO:PANI/NF is a result of a well-connected network of PANI chains alongside NiO. To explore further applications, an all-solid-state symmetrical supercapacitor (SSC) was constructed using the Cu:NiO@rGO:PANI/NF electrodes. This device operates within a voltage range of 0 to 1.5 V, demonstrating a capacitance of 81.9 Fg−1 at 4.5 Ag−1 , with a capacitance retention of 97.6% at a specific current of 10 Ag−1 after 10000 charge-discharge cycles. The symmetrical supercapacitor achieved a maximum energy density of 25.6 Wh kg−1 at a power density of 1297.6 W kg−1 at 4.5 Ag −1 . Considering these findings, the nanocomposite-based solid-state supercapacitor presents a promising option for creating high-performance symmetric supercapacitors
The plateletcrit and hematocrit levels in premature infants with intraventricular hemorrhage
No full textObjective: We investigated the relationship between hematocrit (Hct) and plateletcrit (Pct) values and intraventricular hemorrhage. Methods: This retrospectively analyzed study conducted at the tertiary NICU (Bursa Uludag University Faculty of Medicine) between January 2016 and September 2019. The data of neonates with a gestational age of <32 weeks without and with intraventricular hemorrhage in the first three postnatal days was compared as retrospective. Results: The data of 200 patients were analyzed, including 48 patients with intraventricular hemorrhage and 152 without intraventricular hemorrhage. In the intraventricular hemorrhage group, the values were found to be significantly lower than in the non-intraventricular hemorrhage group for second-day Hct (42.9 +/- 7.6 vs. 47 +/- 6.6, respectively, p<0.001) and third day Hct (37.9 +/- 8 vs. 43 +/- 6.8, respectively, p<0.001). The third-day Pct values were lower in patients with severe intraventricular hemorrhage than in those without intraventricular hemorrhage (0.12 [0.07-0.14] vs. 0.17 [0.12-0.23], respectively, p=0.022). When the Hct and Pct values were evaluated together, it was observed that the secondday HctxPct values of those with second day intraventricular hemorrhage as well as the third day HctxPct values of those with third day intraventricular hemorrhage were lower than in patients without intraventricular hemorrhage. Conclusions: It was observed that the HctxPct values of the same day were lower in patients with intraventricular hemorrhage on days two and three. It was observed that there may be a relationship between low Pct and the severity of intraventricular hemorrhage. Considering the effect of erythrocyte mass on platelets, it may be more appropriate to evaluate Hct and Pct values together in considering the etiology of intraventricular hemorrhage
Can the systemic immune inflammation index (SII) indicate disease activity in patients with rheumatoid arthritis?
No full textObjective This study aimed to investigate the clinical utility of the systemic immune-inflammation index (SII) as a potential marker for disease activity in patients with rheumatoid arthritis (RA). Materials and Methods A total of 104 RA patients aged between 18 and 65 years, along with 69 healthy controls, were included. RA patients were categorised into two subgroups based on the Disease Activity Score-28-Erythrocyte Sedimentation Rate (DAS-28-ESR): remission (DAS-28-ESR 2.6, n=53). Associations between SII and conventional inflammatory markers as well as clinical disease activity indices were examined. Receiver operating characteristic analysis was conducted to assess the diagnostic performance of SII in distinguishing active RA. Results SII levels were significantly elevated in both the overall RA group and particularly in the active RA subgroup (p<0.001). SII showed strong positive correlations with C-reactive protein (r(s)=0.627, p<0.001), ESR (r(s)=0.383, p<0.001), DAS-28-ESR (r(s)=0.775, p<0.001), the simplified disease activity index (r(s)=0.796, p<0.001), and the clinical disease activity index (r(s)=0.798, p<0.001). The most effective SII threshold for identifying active RA was 479.36x10(9)/L, with an area under the curve of 0.968 (95% confidence interval: 0.914-0.993), yielding a sensitivity of 92.45% and specificity of 86.27%. Conclusion SII appears to be a valuable, accessible marker for assessing disease activity in patients with rheumatoid arthritis
Examining the mediating role of moral values in digital environments in the relationship between social and emotional learning and digital well-being among middle school students
No full textBu araştırmanın temel amacı ortaokul öğrencilerinin dijital iyi oluşunun açıklanmasında dijital ortamdaki ahlaki değerlerinin ve sosyal duygusal öğrenmelerinin rolünün incelemektir. Ayrıca, dijital iyi oluş kavramı çeşitli demografik değişkenler açısından ele alınmıştır. Bu araştırma, nicel araştırma yaklaşımına dayalı ilişkisel model çerçevesinde yapılmıştır. Araştırma, 2023-2024 ve 2024- 2025 eğitim-öğretim yıllarında Bursa ilinde bulunan bir ortaokulda öğrenim gören öğrencilerle gerçekleştirilmiştir. Çalışmaya 8. Sınıf öğrencilerinden toplam 662 öğrenci katılmıştır. Araştırmanın katılımcıları, 335 (%50,61) erkek ve 327 (49.39) kadın öğrenciden oluşmaktadır. Araştırmanın verileri, Kişisel Bilgi Formu, Ortaokul Öğrencilerinin Dijital Ortamda Ahlaki Değerlere Dönük Algıları Ölçeği, Sosyal ve Duygusal Öğrenme Ölçeği ve Dijital İyi Oluş Hali Ölçeği kullanılarak toplanmıştır. Verilerin analizinde Hayes-Macro analizi, korelasyon analizi, bağımsız örneklem t-testi ve tek yönlü varyans analizi (ANOVA) uygulanmıştır. Yapılan analizler sonucunda, ortaokul öğrencilerinde sosyal ve duygusal öğrenmenin dijital ortamdaki ahlaki değerleri ve dijital iyi oluşu olumlu ve anlamlı şekilde açıkladığı bulunmuştur. Ayrıca, dijital ortamdaki ahlaki değerlerin dijital iyi oluşu olumlu ve anlamlı şekilde açıkladığı tespit edilmiştir. Bununla birlikte, sosyal ve duygusal öğrenmenin dijital iyi oluşu açıklamasında dijital ortamdaki ahlaki değerlerin olumlu ve anlamlı bir aracı rolünün olduğu ortaya koyulmuştur. Araştırmada dijital iyi oluş düzeylerinin cinsiyet değişkenine göre anlamlı farklılık gösterdiği; ancak günlük internet kullanım süresi ve internet kullanım amaçlarına göre anlamlı bir farklılık göstermediği saptanmıştır.Araştırmadan elde edilen sonuçlar, literatür çerçevesinde değerlendirilmiş ve araştırmacılar ile uygulayıcılara öneriler sunulmuştur.The primary aim of this study is to examine the role of middle school students’ moral values in digital environments and their social and emotional learning in explaining their digital wellbeing. In addition, the concept of digital well-being was addressed in relation to various demographic variables. This research was conducted within the framework of a correlational model based on a quantitative research approach. The study was carried out with students enrolled in a middle school located in Bursa during the 2023–2024 and 2024–2025 academic years. A total of 662 eighth-grade students participated in the study, consisting of 335 male (50.61%) and 327 female (49.39%) students. The research data were collected using the Personal Information Form, the Perceptions of Moral Values in Digital Environments Scale for Middle School Students, the Social and Emotional Learning Scale, and the Digital WellBeing Scale. For data analysis, the Hayes-Macro analysis, correlation analysis, independent samples t-test, and one-way analysis of variance (ANOVA) were employed. The results revealed that social and emotional learning positively and significantly predicted both moral values in digital environments and digital well-being among middle school students. Furthermore, moral values in digital environments were found to positively and significantly predict digital well-being. In addition, it was demonstrated that moral values in digital environments had a positive and significant mediating role in the relationship between social and emotional learning and digital well-being. The study also indicated that digital well-being levels differed significantly by gender, whereas no significant differences were observed in terms of daily internet usage time or purposes of internet use. The findings of this research were discussed in the context of the existing literature, and recommendations were provided for both researchers and practitioners