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A modified artificial protozoa optimizer for robust parameter identification in nonlinear dynamic systems
No full textAccurate parameter identification in nonlinear and chaotic dynamic systems requires optimization algorithms that can reliably balance global exploration and local refinement in complex, multimodal search landscapes. To address this challenge, a modified artificial protozoa optimizer (mAPO) is developed in this study by embedding two complementary mechanisms into the original artificial protozoa optimizer: a probabilistic random learning strategy to enhance population diversity and global search capability, and a Nelder-Mead simplex-based local refinement stage to improve exploitation and fine-scale solution adjustment. The general optimization performance and scalability of the proposed framework are first evaluated using the CEC2017 benchmark suite. Statistical analyses conducted over shifted and rotated, hybrid, and composition functions demonstrate that mAPO achieves improved mean performance and reduced variability compared with the original APO, indicating enhanced robustness in high-dimensional and complex optimization problems. The effectiveness of mAPO is then examined in nonlinear system identification applications involving chaotic dynamics. Offline and online parameter identification experiments are performed on the R & ouml;ssler chaotic system and a permanent magnet synchronous motor, including scenarios with abrupt parameter variations. Comparative simulations against APO and several state-of-the-art optimizers show that mAPO consistently yields smaller objective function values, more accurate parameter estimates, and superior statistical stability. In the PMSM case, exact parameter reconstruction with zero error is achieved across all independent runs, while rapid and smooth convergence is observed under both static and time-varying conditions
Nasopharyngeal pneumococcal carriage and serotype landscape in children, adolescents and young adults in Türkiye
No full textAfter the widespread use of pneumococcal conjugated vaccines (PCVs), pneumococcal carriage, especially due to some vaccine serotypes, has been shown to decrease, but carriage with non-vaccine serotypes and some persistent vaccine types of lineages has been demonstrated to continue. Evaluation of pneumococcal carriage helps to understand disease epidemiology. In this multicenter study, we aimed to determine pneumococcal carriage and serotype distribution in children, adolescents, and young adults aged 0-24 years in T & uuml;rkiye after the pandemic era. This multicenter study was conducted between April and August 2022 in 1585 healthy children, adolescents, and young adults (aged between 0 and 24 years) in nine centers in T & uuml;rkiye. Demographics, schooling/day-care, smoking exposure, recent upper respiratory tract infection (URTI), antibiotic use (1 and 3 months), COVID-19 infection/vaccination, and pneumococcal vaccination history were recorded. Nasopharyngeal swab samples were taken from all participants. Streptococcus pneumoniae was detected by real-time polymerase chain reaction (PCR); positives were serotyped by singleplex real-time PCR assays targeting 33 serotypes/serogroups. Among 1 585 participants (797 female; age distribution 0-5 years 22.0%, 6-10 years 29.3%, 11-15 years 16.8%, 16-18 years 12.9%, 19-24 years 19.0%), overall pneumococcal carriage prevalence was 19.6% (311/1 585). Age-specific prevalences were 20.7% (0-5 years), 21.8% (6-10 years; peak), 19.1% (11-15 years), 15.6% (16-18 years), and 18.2% (19-24 years). Two-thirds (66.2%) had received >= 1 PCV dose (coverage >= 82% through 15 years, declining to 43.9% at 16-18 years and 13.3% at 19-24 years). Vaccination was associated with significantly lower carriage only in children <= 10 years: 0-5 years 17.8% vs 43.6% (OR 0.28, 95% CI 0.13-0.60, p < 0.001); 6-10 years 19.7% vs 32.4% (OR 0.51, 0.28-0.93, p = 0.021). No significant differences were seen in older strata or overall (18.8% vs 21.3%, OR 0.85, 0.65-1.12). Of 311 isolates, 225 (72.4%) were typed (27 serotypes) and 86 (27.6%) were not defined. Dominant serotypes were 19F, 6A/B, 3, 23F, and 15B/C; PCV13 serotypes comprised 77.3% of typed isolates. Theoretical vaccine coverage among 225 typed isolates increased from 61-64% (PCV7/10) to 77.3% (PCV13), 78.2% (PCV15), 88.4-90.2% (PCV20/24), plateauing at 93.3-93.8% for PCV31/25. Theoretical vaccine coverage in children aged below 5 years of age was 66.7% for PCV13, 70.0% for PCV15, and 88.3% for PCV20. The frequency of PCV13 serotypes in children vaccinated with PCV13 was significantly lower than in unvaccinated children in children below 5 years of age.Eskisehir Osmangazi Universit
Investigation about the potential of citron, sweet lemon, and sweet orange peels as herbal tea
No full textThis study investigated the sensorial quality, chemical composition, and bioactive potential of herbal teas made from the peels of sweet lemon (Citrus limetta Risso), sweet orange (Citrus sinensis (L.) Osbeck), and citron (Citrus maxima (Burm.) Merr) using freeze-drying, hot-air drying, and microwave drying. Sensory evaluation showed that teas from microwave-dried peels were most preferred, with microwave-dried sweet orange peel tea receiving the highest acceptability score (6.78/9). In contrast, freeze-dried sweet orange peel tea had the highest total phenolic content (843.40 mg gallic acid equivalent, GAE/L), while the microwave-dried version had the lowest (279.20 mg GAE/L). Hesperidin, protocatechuic acid, and chlorogenic acid were dominant in different citrus teas. Key volatiles included linalool in sweet lemon, naphthalene in sweet orange, and 2-furanmethanol derivative in citron. Sweet lemon peel tea had the highest antioxidant activity (0.90 mmol trolox equivalent, TE/L) and gastric bioaccessibility (0.22 mmol TE/L). Simulated digestion reduced most bioactive compounds; however, hesperidin, syringic acid, chlorogenic acid, protocatechuic acid, and luteolin-7-glycoside remained detectable depending on the tea type. Pesticide residues were found only in microwave-dried sweet orange peel tea, but remained below legal limits. While microwave drying enhanced sensory appeal, freeze-drying better preserved bioactive compounds. Overall, citrus peels show strong potential as sustainable raw materials for functional herbal teas
Triacetoxyvinylsilane-based polymer intercalated-graphene for enhanced 3d ni foam electrodes in energy storage applications
No full textThis study demonstrates the exceptional supercapacitive performance of a novel P(EGDMA-TAVS)-graphene composite on nickel foam (NF) substrate. The three-dimensional porous architecture, combining the high conductivity of graphene with the robust polymeric framework of poly(ethylene glycol dimethacrylate-trimethylolpropane allyl ether vinyl sulfonate) [P(EGDMA-TAVS)], enables outstanding electrochemical properties. The p(EGDMA-TAVS)-graphene/NF electrode demonstrates specific capacitances of 963.9, 817.2, 746.1, 716.4, 650.6, and 603.5 F g-1 when tested at scan rates of 10, 20, 30, 50, and 70 mV s-1, respectively. The enhanced interfacial adhesion provided by p(EGDMA-TAVS), together with graphene's efficient electron-transport network on the nickel foam current collector, yields an energy density of 40.3 Wh kg-1 at a power density of 4773.6 W kg-1 in 3 M KOH. The p(EGDMA-TAVS)-graphene/NF electrode preserves 95.6% of its starting capacitance over 2500 cycles at 6 A g-1. These results position the P(EGDMA-TAVS)-graphene/NF electrode as a promising candidate for high-performance energy storage applications
Tsrs-aligned sustainability reporting in turkey's agri-food sector: A qualitative content analysis based on gri 13 and the sdgs
No full textSustainability in the agri-food sector has become a cornerstone of global efforts to combat climate change, ensure food security through climate-smart agriculture, and strengthen economic resilience. Sustainability reporting within agri-food systems has gained increasing regulatory significance with the introduction of mandatory frameworks such as the Turkish Sustainability Reporting Standards (TSRSs). This article searches for the sustainability reports of agri-business firms listed in BIST in Turkey. Although TSRS reporting is not yet mandatory for the agribusiness sector, this study examines the first TSRS-aligned sustainability reports published by eight agri-food companies, excluding the retail sector. The analysis assesses how effectively these reports address sector-specific environmental and social challenges defined in the GRI 13 Agriculture, Aquaculture and Fishing Sector Standard and their alignment with the United Nations Sustainable Development Goals (SDGs). Using a structured content analysis approach, disclosure patterns were examined at both thematic and company levels. The findings indicate that TSRS-aligned reports place strong emphasis on environmental and climate-related disclosures, particularly emissions, climate adaptation and resilience, water management, and waste. In contrast, agro-ecological and land-based impacts-such as soil health, pesticide use, and ecosystem conversion-are weakly addressed. Economic disclosures are predominantly framed around climate-related financial risks and supply chain traceability, while social reporting focuses mainly on occupational health and safety, employment practices, and food safety, with limited attention to labor and equity issues across the broader value chain. Company-level results reveal marked heterogeneity, with internationally active firms demonstrating deeper alignment with GRI 13 requirements. From an SDG alignment perspective, high levels of coverage are observed across all companies for SDG 13 (Climate Action), SDG 12 (Responsible Consumption and Production), and SDG 6 (Clean Water and Sanitation). By contrast, SDGs critical to agro-ecological integrity and social equity-namely SDG 1 (No Poverty), SDG 2 (Zero Hunger), SDG 10 (Reduced Inequalities), and SDG 15 (Life on Land)-are weakly represented or entirely absent. Overall, the results suggest that while TSRS-aligned reporting enhances transparency in climate-related domains, it achieves only selective alignment with the SDG agenda. This underscores the need for a stronger integration of sector-specific sustainability priorities into mandatory sustainability reporting frameworks
Ex vivo evaluation of cd3 + cd8 + t cell subpopulations in red blood cell concentrates: Does storage time play an important role?
No full textBackground/Objectives: Our study was designed to explore the potential role of allogeneic CD8+ T lymphocytes present in red blood cell concentrates (RBCs) in the development of transfusion-related immunomodulation (TRIM) and the effect of storage time on these cells. Methods: From six units of whole blood, donated by volunteers, RBCs were obtained and each one was divided into three equal parts to provide the samples for storage days 0, 21, and 42. On related days, mononuclear cells (MNCs) were isolated from these RBC samples. MNCs were cultured, and phytohemagglutinin was added to half of the culture wells to stimulate the cells and achieve T cell division. Supernatants and MNCs were obtained from stimulated (STI) and unstimulated (US) wells. Supernatants were used for cytokine analyses, while MNCs were used to investigate the T cells and transcription factors. Results: The frequency of CD8+ T lymphocytes (Tc), their subgroups (Tc1, Tc2, and Tc17), specific transcription factors, and effector cytokines decreased during the storage time, but cell viability increased. CD3+CD8+TNF-alpha+ cells were significantly higher in the STI group on day 0 compared to the US group. Other cells did not respond to the mitogen (phytohemagglutinin) stimulation. Conclusions: During storage, the number of Tc cells and their ability to respond to mitogens decreased over time. The unresponsiveness was not recovered in ex vivo cell culture. Our findings suggest that transfused Tc cells are unlikely to be primary mediators of TRIM
Real-world effectiveness and safety of eculizumab in aqp4-igg-positive neuromyelitis optica spectrum disorder
No full textObjectiveTo evaluate the real-world effectiveness and safety of eculizumab in patients with AQP4-IgG-positive neuromyelitis optica spectrum disorder (NMOSD) and to identify predictors of disability outcomes.MethodsThis multinational, retrospective cohort study analyzed data from 46 patients across 26 centers. The outcomes included the annualized relapse rate (ARR), relapse-free status, change in expanded disability status scale (EDSS) scores, and adverse events. To identify predictors of EDSS improvement or worsening, patients were stratified into subgroups (improved vs. stable/worsened) at each follow-up time point and compared based on demographic, clinical, and radiological variables.ResultsThis retrospective cohort study included 46 patients with AQP4-IgG-positive NMOSD from 26 centers, followed for a mean of 27.3 months. The mean ARR significantly decreased from 1.1 in the 2 years pre-treatment to 0.1 during eculizumab therapy. The relapse-free rate increased from 6.5% pre-treatment to 80.4%. Mean EDSS scores improved from 4.2 at baseline to 3.6 at 24 months. The presence of area postrema syndrome was associated with a favorable prognosis, while the presence of spinal attacks was associated with a poor prognosis at 12 months. Adverse events occurred in 7 patients (18.9%), leading to permanent discontinuation in only two.ConclusionEculizumab demonstrated robust real-world effectiveness in reducing relapse rates and stabilizing disability, with an acceptable safety profile. Clinical outcomes may be influenced by attack phenotype, underscoring the importance of early intervention
Bulky auricular folliculotropic mycosis fungoides: Dramatic response and rechallenge efficacy with extended brentuximab vedotin therapy
No full textA comparison of universıty students’ levels of gratitude and social responsibility in Turkey and Kyrgyzstan according to gender and faculty variables
No full textBu araştırmanın amacı, Türkiye ve Kırgızistan örneklemlerinde üniversite öğrencilerinin minnettarlık ve sosyal sorumluluk düzeylerini ülke, cinsiyet ve öğrenim görülen fakülte değişkenleri açısından karşılaştırmaktır. Araştırma, nicel araştırma yöntemlerinden ilişkisel tarama modeliyle yürütülmüştür. Çalışmanın evrenini 2023–2024 eğitim-öğretim yılında Bursa Uludağ Üniversitesi ile Kırgızistan-Türkiye Manas Üniversitesi’nde lisans düzeyinde öğrenim gören öğrenciler oluşturmaktadır. Kolayda örnekleme yöntemiyle belirlenen örneklem, Türkiye’den 242 ve Kırgızistan’dan 273 olmak üzere toplam 515 üniversite öğrencisinden meydana gelmiştir. Veri toplama araçları olarak Kişisel Bilgi Formu, Minnettarlık Ölçeği ve Sosyal Sorumluluk Ölçeği kullanılmıştır. Verilerin analizinde iki yönlü varyans analizi (Two-Way ANOVA) uygulanmıştır. Araştırma bulgularına göre, ülke değişkenine göre hem minnettarlık hem de sosyal sorumluluk bakımından Türkiye ve Kırgızistan örneklemleri arasında anlamlı puan farklılıkları olmadığı; Kırgızistan örneklemindeki öğrencilerin her iki değişkende de Türkiye örneklemindeki öğrencilere kıyasla daha yüksek puanlara sahip olduğu belirlenmiştir. Cinsiyet değişkeni açısından minnettarlık düzeylerinin her iki ülkede de farklılaşmadığı, sosyal sorumluluk düzeylerinin ise kadın öğrenciler lehine anlamlı biçimde farklılaştığı saptanmıştır. Fakülte değişkeni incelendiğinde, minnettarlık ve sosyal sorumluluk düzeylerinin fakülte türüne göre anlamlı biçimde farklılaştığı ve ülke farkının fakültelere göre değişkenlik gösterdiği belirlenmiştir. Sosyal sorumluluk açısından, İktisat ve İlahiyat fakültelerinde öğrenim gören Kırgızistan örneklemindeki öğrencilerin puanlarının Türkiye örneklemine kıyasla daha yüksek olduğu görülmüştür. Minnettarlık düzeylerinde ise Güzel Sanatlar, İktisat ve Eğitim/Edebiyat fakültelerinde ülke farkının Kırgızistan örneklemindeki öğrenciler lehine daha belirgin olduğu saptanmıştır. Elde edilen sonuçlar, minnettarlık ve sosyal sorumluluk düzeylerinin kültürel bağlamdan etkilendiğini ve üniversite öğrencilerinde bu değişkenlerin fakülte temelli olarak farklılaştığını göstermektedir. Bulgular doğrultusunda, üniversitelerde kültürel duyarlılığı gözeten, fakülte temelli ve sosyo-duygusal gelişimi destekleyen uygulamaların önemine dikkat çekilmektedir.The aim of this study is to compare the levels of gratitude and social responsibility of university students in Turkey and Kyrgyzstan in terms of country, gender, and faculty variables. The study was conducted using a relational survey model, one of the quantitative research methods. The population of the research consisted of undergraduate students enrolled at Bursa Uludağ University and Kyrgyz–Turkish Manas University during the 2023–2024 academic year. The sample was determined through convenience sampling and comprised a total of 515 volunteer undergraduate students, including 242 students from Turkey and 273 students from Kyrgyzstan. Data were collected using a Personal Information Form, the Gratitude Scale, and the Social Responsibility Scale. Two-way analysis of variance (Two-Way ANOVA) was employed to analyze the data. According to the research findings, although there were no statistically significant differences between the Turkey and Kyrgyzstan samples in terms of gratitude and social responsibility based on the country variable, students in the Kyrgyzstan sample obtained higher mean scores on both variables compared to students in the Turkey sample. In terms of gender, gratitude levels did not differ significantly in either country, whereas social responsibility levels were significantly higher among female students. When the faculty variable was examined, both gratitude and social responsibility levels were found to differ significantly across faculty types, and the magnitude of country differences varied by faculty. In terms of social responsibility, students from Kyrgyzstan studying in the Faculties of Economics and Theology scored significantly higher than their counterparts in Turkey. Regarding gratitude, country-based differences were more pronounced in favor of Kyrgyzstan among students enrolled in the Faculties of Fine Arts, Economics, and Education/Literature. Overall, the results indicate that gratitude and social responsibility are influenced by cultural context and that these socio-emotional variables vary across faculties among university students
A sociological study on the construction of new meaning worlds for atheist individuals
No full textBu araştırmada post-modern toplumlarda dinin anlam üretme işlevinin zayıflamasıyla ateist bireylerin yeni anlam dünyaları inşa süreçleri sosyolojik bir bakış açısıyla ele alınmıştır. Anlam dünyası, birey-toplum etkileşimi ile inşa edilen dinamik bir süreçtir. Birey gündelik hayatın gerçekliği içinde yeni bir anlam dünyası inşa eder. Ateistler, günümüzde sadece bireysel bir tercih olmanın ötesinde, dernekler ve çeşitli sosyal ağlar aracılığıyla görünürlük kazanan bir topluluk biçimi oluşturmaktadır. Teknolojinin gelişmesiyle bilgiye hızlı erişim sağlanmakta, din ve ateizmle ilgili gelişmeler sosyal medya ve web siteleri aracılığıyla çok daha hızlı yayılmaktadır. Günümüzde Türkiye’de ateizm, deizm, agnostisizm gibi kavramlar hem bireysel hem kamusal düzeyde yeniden gündeme gelmektedir. Bu çalışmanın amacı bireylerin ateizme yönelmesinde etkili olan faktörleri, geçmişten günümüze ateizmin aldığı yol ve yeni ateizm söylemleri arasındaki farklılıkları ortaya koyarak bireylerin ateist olma süreçlerine ve hayatı anlamlandırma biçimlerine dair sosyolojik bir analiz sunmaktadır. Kendini ateist olarak tanımlayan bireylerin geçmiş tecrübeleri, etkilendikleri yayın ve kişiler, psiko-sosyal ve siyasi-politik sebepler sosyolojik bakış açısıyla ortaya konulmaya çalışılmıştır. Araştırmada, kendini ateist olarak tanımlayan, Bursa ve İstanbul’da yaşayan 15 katılımcı fenomenolojik desenle, yarı yapılandırılmış mülakat tekniğine dayalı nitel çalışma yürütülmüştür. Araştırmada Peter L. Berger’in “Sembolik Evren” kuramı çerçevesinde Türkiye’de ateizmin anlam inşası üzerine sosyolojik bir analiz yapılmıştır. Araştırmamızda, ateist bireylerin çoğunlukla süreç içerisinde sorgulama ve düşünsel dönüşümle bireysel tercihle ateist oldukları, sosyal medya ve okumaları, aile-arkadaş çevresi, yaşanan olumsuz tecrübeler, bilimsel verilere yüklenen anlam gibi etkenler doğrultusunda yeni anlam dünyası inşa ettikleri tespit edilmiştir. Bilimsellik, rasyonalite, bireysel ahlak anlayışı ve özgürlük arayışı bireylerin yeni anlam dünyalarını şekillendiren önemli unsurlardır. Katılımcı anlatılarında sanat, bilim ve eğlence gibi seküler faaliyetlerin anlam ve gündelik hayatla ilişkilendirildiği anlaşılmaktadır. Dernek ya da grup faaliyetlerine ihtiyaç duyulmasa da ateist çevreler ise aidiyet duygusu sağlamakla birlikte bireyler için zorunlu bir topluluk biçimi olarak görülmemektedir.This study examines the processes by which atheist individuals construct new worlds of meaning from a sociological perspective, given the weakening of religion's function of producing meaning in post-modern societies. The world of meaning is a dynamic process constructed through individual-society interaction. Individuals construct a new world of meaning within the reality of everyday life. Atheists today form a community that goes beyond being merely an individual choice, gaining visibility through associations and various social networks. With the advancement of technology, information is readily accessible, and developments related to religion and atheism spread much faster through social media and websites. Today in Turkey, concepts such as atheism, deism, and agnosticism are back on the agenda at both the individual and public levels. The aim of this study is to present a sociological analysis of individuals' processes of becoming atheists and their ways of making sense of life by revealing the factors that influence individuals' turn to atheism, the path atheism has taken from the past to the present, and the differences between new atheism discourses. The past experiences of individuals who identify as atheists, the publications and people who have influenced them, and psycho-social and political-ideological reasons have been examined from a sociological perspective. The study involved a qualitative research based on a phenomenological patterned semi-structured interview technique with 15 participants living in Bursa and Istanbul who identified themselves as atheists. The study provides a sociological analysis of the construction of meaning in atheism in Turkey, within the framework of Peter L. Berger's "Symbolic Universe" theory. Our research found that atheist individuals mostly became atheists through questioning and intellectual transformation during the process, and that they constructed a new world of meaning based on factors such as social media and reading, family and friends, negative experiences, and the meaning attributed to scientific data. Scientificity, rationality, individual moral understanding, and the pursuit of freedom are important elements that shape individuals' new worlds of meaning. It is understood that in the participants’ narratives, secular activities such as art, science and entertainment are associated with meaning and everyday life. Although there is no need for association or group activities, atheist circles are seen as providing a sense of belonging but not as a mandatory form of community for individuals