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Myelitis after liver transplant: A case report
No full textWe report a case of neurotoxicity as a side effect of a calcineurin inhibitor (tacrolimus), which is used as an immunosuppressive drug after liver transplant. Our patient had chronic hepatic failure due to Budd-Chiari syndrome and underwent a liver transplant after an appropriate deceased donor organ was obtained. After organ transplant surgery, he was kept under the effect of an immunosuppressive drug (tacrolimus) with daily control of the level of drug in his blood to avoid drug toxicity. Despite the level of drug in his blood being within the ideal range, the patient developed neurotoxicity that presented as weakness of his extremities. Appropriate diagnostic tests were done, and all proved that these signs and symptoms were related to the use of tacrolimus. Therefore, the drug was changed to cyclosporine. After a few months, the patient regained normal neurological functions of his extremities. We should take precautions to monitor neurological symptoms and signs while we administer calcineurin inhibitors
Can animals think?
No full textBirçok kişi, hayvanların insanlar kadar olmasa da en azından sınırlı bir düşünce yetisine sahip olduğuna inanır. Dennett’e göre ise, hayvanların düşünebildiğini söylemek oldukça zordur. Zeki hayvan davranışları düşünmeyen yönelimsellik örnekleri olarak betimlenebilir. Bazen insanlar da düşünmeden eyleme geçer; yalnız, hayvanlardan farklı olarak insanlar bu otomatikleşmiş davranışların yerleşmesinden önce uzun ve bilinçli bir öğrenme sürecinden geçerler. Dennett, hayvan düşüncesi karşıtı fikirlerini geliştirdikten sonra hayvan düşüncesini destekleyen köklü fikirleri rahatsız etmek için bu fikirleri geliştirdiğini itiraf eder (Dennett 1996). Yalnız, Dennett’in seçtiği örnekler ve geliştirdiği argümanlar makul bir şüpheyi yerleştirmeye çalışırken beklenmedik sorunlar çıkarır. Örnekler ağırlıklı olarak işlemsel bellek süreçleriyle ilgili örneklerdir; halbuki hayvanların düşünüp düşünemediği ile ilgili bir şüphe yaratmak için bakılması gereken süreçler işlemsel bellek süreçleri değil, olaysal bellek süreçleridir. Ayrıca, Dennett’in iddiasının aksine, insanlarda da her işlemsel bellek sürecinin öncesinde bilinçli bir öğrenme süreci gerekmemektedir. Özetle, hayvanların düşünmesi konusundaki şüphecilik hala haklı olabilir, ancak bu Dennett’in öne sürdüğü nedenler ve en çok tercih ettiği örnekler yüzünden değil, başka nedenlerden dolayıdır. Bizim görüşümüze göre ise, şu andaki veriler doğrultusunda kesin olarak hayvanların ne düşünebildiği ne de düşünemediği söylenebilir.While not as much as humans, many believe that animals have at least a limited capacity for thought. According to Dennett, it is very problematic to assert that animals are capable of thinking. Intelligent animal behaviors can be described as instances of unthinking intentionality. Sometimes people act without thinking, but unlike animals, humans go through a prolonged and conscious learning process before those automatic behaviors become established. Dennett, having developed his ideas opposing animal thinking, confesses that he aimed to disturb some of the deeply rooted views supporting animal thinking (Dennett 1996). Still, Dennett's chosen examples and developed arguments present unexpected issues when trying to establish a reasonable doubt. The examples primarily focus on procedural memory processes, yet, to cast doubt about whether animals think, the focus should be on episodic memory processes, not procedural memory processes. Furthermore, not all procedural memory processes, contrary to Dennett's view, require conscious process of learning beforehand in humans. In summary, the skepticism regarding animal thinking may still be warranted, not because of Dennett’s reasons and examples Dennett favors most, but for other reasons. In our opinion, based on the current data, it is not possible to state definitely whether animals can think or cannot think
Sustainable design of broadband radar absorbers using metallurgical waste and multi-objective optimization
No full textThis study proposes a sustainable approach for converting metallurgical waste into value-added electromagnetic materials for broadband radar absorption applications. A total of 105 samples are fabricated from 14 industrial waste types using various shaping and additive techniques, and then electromagnetically characterized. A novel double-stage Artificial Bee Colony (DS-ABC) optimization algorithm is developed to design an effective five-layer absorber by independently optimizing layer sequence and thickness for transverse electric (TE) and transverse magnetic (TM) polarizations. The resulting multilayer structure achieves over 90 % absorption across the 2-18 GHz frequency range under multiple incidence angles. Beyond technical performance, this work demonstrates a scalable method for replacing hazardous waste with functional materials, thereby reducing environmental impact and aligning with the principles of a circular economy. The proposed approach offers practical relevance for sectors requiring electromagnetic interference (EMI) shielding and stealth technologies. It also contributes to sustainable production practices by repurposing industrial by-products
Thermodynamic evaluation of nanorefrigerant-enhanced cascade refrigeration system
No full textThis study investigates the thermodynamic performance of a cascade refrigeration cycle (CRC) enhanced with ZrO2 and TiO2nanoparticles using various refrigerants. The analysis, conducted using the Engineering Equation Solver (EES), examines key performance parameters such as the coefficient of performance (COP), exergy efficiency, exergy destruction, and compressor work. The findings suggest that nanorefrigerants enhance energy efficiency, with R600 demonstrating the highest COP and exergy efficiency, while R507a exhibits the lowest. It has been demonstrated that the COP and overall exergy efficiency of nano refrigerants with ZrO2 nanoparticles exceed those of TiO2. Additionally, the study highlights the potential of low-global-warming-potential (GWP) refrigerants combined with nanoparticles for enhancing refrigeration performance. The findings provide insights into the viability of nanofluid applications in CRCs and suggest future experimental research to validate the theoretical results
Evaluation of metabolism-related molecules in rat model of autism spectrum disorders
No full textAutism spectrum disorders (ASD) are neurodevelopmental pathologies. Investigating both sexes is crucial for understanding sex-specific manifestations of ASD. This study aims to examine ASD-like behaviours and metabolic alterations in male and female rats prenatally exposed to valproic acid (VPA). Pregnant Wistar albino rats were administered 400 mg/kg VPA or saline on embryonic day 12. Pups were subjected to various behavioural tests, including olfactory discrimination, sociability, locomotion, anxiety and exploratory behaviour assessments. On postnatal day 35, pups were sacrificed, and blood glucose levels were measured. Serum and brain leptin, orexin-A, nesfatin-1 and ghrelin levels were assessed by the ELISA method. VPA-exposed pups exhibited increased latency to reach maternal bedding, reduced sociability, decreased locomotion and increased immobility in both sexes. In the elevated plus maze, VPA-exposed females showed an increase in open-arm entries, while males showed a reduction compared to control groups. Blood glucose levels were significantly elevated in VPA-exposed males but not females. Significant sex-independent changes were observed in serum and brain levels of leptin and nesfatin-1 in the VPA groups. Brain orexin-A and serum ghrelin levels were altered in the VPA group in a sex-dependent manner. Prenatal VPA exposure induces ASD-like symptoms in both sexes, with notable sex-specific differences in behaviour and metabolic regulation. These findings highlight the importance of including both sexes in ASD research to better understand sex-dependent characteristics of the disorder, particularly concerning metabolic dysregulation
Investigation of the effects of mononuclear leukocytes on platelet functions and hemostasis
No full textEfficient one-pot strategy for fluorescent conjugated polymers derived from 8-amino-1-naphthalene-3,6-disulfonic acid: Synthesis, thermal and optical properties
No full textSchiff base polymers, also known as poly(imines) or poly(azomethine)s, constitute a subset of conjugated polymers. The Schiff base compound was synthesized via the condensation reaction between 8-amino-1-naphthalene-3,6-disulfonic acid and 4-hydroxybenzaldehyde. Subsequently, both 8-amino-1-naphthalene-3,6-disulfonic acid and its Schiff base derivative were polymerized into a poly(naphthol) (PANAPDSA) and Schiff base polymer (PANAPDSASB) under alkaline condition using H2O2 (35 % aqueous solution) as oxidant via oxidative polycondensation (OP). The chemical structures of the synthesized compounds were approved using NMR, FT-IR, UV–Vis, element and LC-MS/MS spectroscopic techniques. The synthesized polymers exhibited lower optical and electrochemical band gaps compared to their respective monomers, suggesting their potential utility as semiconductor materials. The poly(naphthol) derivative exhibited high fluorescent emission intensity of 1000 a.u. when excited at 300 nm with a photoluminescence (PL) emission quantum yield of 13.6 % at 392 nm of emission wavelength in N,N-dimethylformamide (DMF) solution. Weight average molecular weight (Mw) values of PANAPDSA and PANAPDSASB ranged from 9500 Da to 11200 Da, with PDI values between 1.12 and 1.13. The synthesis of conjugated polymers could hold significant importance in technological advancements
Field-based evaluation of multi-strain pgpr to improve zea mays yield and soil nutrient dynamics in semi-arid of türkiye
No full textSoil fertility decline and overuse of agrochemicals threaten sustainable maize (Zea mays L.) production in semi-arid regions of T & uuml;rkiye. Plant growth-promoting bacteria (PGPB) offer a biologically based alternative by enhancing nutrient uptake, root development, and soil health. In this field-based study, we evaluated the effects of a five-strain PGPR consortium (Azotobacter spp., Bacillus sp., Paenibacillus sp., Pantoea sp., and Pseudomonas sp.) on maize productivity and soil nutrient dynamics. A randomized split-plot design was used, involving four commercial maize hybrids and four inoculant doses (0, 100, 130, 160 mL/da). PGPR application significantly improved soil organic matter, phosphorus availability, and cation exchange capacity, particularly at the tasseling stage. The 130 mL/da dose yielded the highest grain productivity, suggesting optimized biological nitrogen fixation and water-use efficiency. Leaf analysis at the V15 stage revealed genotype-specific nutrient responses and elevated Zn and Cu levels under inoculated treatments, indicating enhanced micronutrient solubilization but also potential risk of nutrient imbalance. Our findings support the use of non-commercial, field-formulated PGPR consortia as a scalable component of sustainable maize systems, especially under climate-stressed conditions. The cultivar x dose interaction underscores the need for genotype-specific microbial strategies in precision agriculture
Investigation of the properties of pedot-coated cotton and poliester fabrics via vapor phase polymerization for sensor applications
No full textBu tez, giyilebilir teknolojilerde kullanılmak üzere farklı kumaşların PEDOT ile kaplanarak iletken hale getirilmesi ve gerinim sensörü olarak potansiyellerini incelemeyi amaçlamaktadır. PEDOT üretiminde Buhar Fazında Polimerizasyon (VPP) yöntemi seçilmiş, yüksek iletkenlik sağlamak için çok yönlü bir teknik olduğu görülmüştür. Özellikle yeni tasarlanan polimer kabini sayesinde, PEDOT kaplamanın kumaş yüzeyine homojen bir şekilde uygulanması mümkün olmuş ve tüm kumaş türlerinin başarılı bir şekilde iletken hale getirilebileceği gösterilmiştir. Bu çalışmada, PEDOT iletken polimeri; pamuk, poliester ve poliester/pamuk karışımı kumaşlar üzerine kaplanmış, iletkenlik ve sensör performansları test edilmiştir. PEDOT kaplaması ile kumaşlar düşük direnç, yüksek iletkenlik ve çevresel dayanıklılık göstermiştir. Gerinim sensörlerinde doğrusal olmama ve histerezis gibi sorunların önüne geçmek için kumaşlar poliüretan ile kaplanmış ve bu kaplama, sensörlerin esnekliğini artırarak gerilme sonrası orijinal durumuna dönmesini sağlamıştır. Ayrıca, gösterge faktörü %5 ve %10 gerilmelerde yaklaşık 10 olarak hesaplanmıştır. Deneyler, 50 mm/dk çekim hızının sensör performansı için en uygun hız olduğunu, artan çekim hızlarının histerezisi artırarak doğrusallığı azalttığını göstermiştir. SEM analizleri ise poliüretan kaplamasız kumaşların, gerilme altında çatlaklar ve kırıklar oluşturduğunu, bu durumun düzensiz direnç değişimlerine yol açtığını ortaya koymuştur. Poliüretan kaplama ile bu deformasyonların önüne geçilmiş ve sensörlerin uzun vadeli performansı iyileştirilmiştir. Bu çalışmanın bulguları, akıllı tekstil ve giyilebilir sensör teknolojilerinde PEDOT kaplı kumaşların kullanım potansiyelini göstermektedir. Gelecek çalışmalar için farklı kaplama ve polimer materyalleriyle yapılacak araştırmaların, sensör performansını daha da iyileştirebileceği öngörülmektedir. Bu tez, giyilebilir sensörlerde kullanılacak dayanıklı, esnek ve çevre dostu tekstil yüzeylerinin geliştirilmesine katkıda bulunmayı hedeflemektedir.This thesis aims to investigate the potential of using various types of fabrics coated with PEDOT through Vapor Phase Polymerization (VPP) as strain sensors for wearable technologies. VPP was chosen as the PEDOT production method, proving to be a versatile technique for achieving high conductivity. The newly designed polymerization chamber has enabled uniform PEDOT coating on fabric surfaces, demonstrating that all fabric types can be successfully made conductive.In this study, PEDOT conductive polymer was coated on cotton, polyester, and cotton/polyester blend fabrics, and their conductivity and sensor performance were tested. With PEDOT coating, fabrics showed low resistance, high conductivity, and improved environmental durability. To address issues such as non-linearity and hysteresis in strain sensors, polyurethane coating was applied to the fabrics, enhancing the elasticity of the sensors and allowing them to return to their original state after stretching. Additionally, the gauge factor was calculated to be around 10 at 5% and 10% strain levels. Experiments indicated that a pull rate of 50 mm/min is optimal for sensor performance, as increased pull rates were found to elevate hysteresis and reduce linearity. SEM analyses revealed that uncoated fabrics developed cracks and fractures under strain, leading to irregular resistance changes. Polyurethane coating helped prevent these deformations, thus improving the long-term performance of the sensors. The findings of this study highlight the potential of PEDOT-coated fabrics in smart textiles and wearable sensor technologies. Future research involving various coating and polymer materials is anticipated to further enhance sensor performance. This thesis contributes to the development of durable, flexible, and eco-friendly textile surfaces suitable for wearable sensors
Portopulmonary hypertension in liver transplant candidates: Echocardiographic screening, prevalence, and long-term outcomes
No full textIntroduction and Objectives: Portopulmonary hypertension (PoPH) represents a significant pulmonary vascular complication in patients with portal hypertension, substantially increasing perioperative mortality during liver transplantation (LT). While systematic transthoracic echocardiographic (TTE) screening has become standard practice, optimal diagnostic thresholds and prevalence data across diverse populations remain incompletely characterized. This investigation sought to determine the prevalence of PoPH among LT candidates at a tertiary hepatology center, comprehensively characterize the clinical and hemodynamic profiles of affected patients, and evaluate the diagnostic efficacy of TTE screening protocols. Patients or Materials and Methods: We conducted a comprehensive retrospective analysis of 422 consecutive LT candidates with portal hypertension evaluated at our tertiary center between 2007–2017. All patients underwent systematic TTE, with right heart catheterization (RHC) performed when right ventricular systolic pressure (RVSP) exceeded 40 mmHg or when indirect pulmonary hypertension indicators were present. PoPH was defined according to currently established hemodynamic criteria: mean pulmonary arterial pressure >20 mmHg, pulmonary vascular resistance >2 Wood units, and pulmonary arterial wedge pressure ≤15 mmHg. Results: Among 422 patients (mean age 52.9 ± 12.3 years, 67.5 % male), chronic hepatitis B predominated (35.1 %). Fifty-two patients underwent RHC, with twenty (4.74 % of total cohort) receiving definitive PoPH diagnosis. PoPH patients demonstrated significantly higher pulmonary vascular resistance (3.51 ± 1.90 vs 1.25 ± 1.02 Wood units, p < 0.001), and transpulmonary gradient (18.05 ± 9.28 vs 9.56 ± 8.43 mmHg, p = 0.001), while reduced pulmonary arterial wedge pressure (9.45 ± 1.73 vs 13.53 ± 4.81 mmHg, p < 0.001), cardiac output (5.21 ± 0.95 vs 7.57 ± 1.38 L/min, p < 0.001), and cardiac index (2.97 ± 0.98 vs 4.15 ± 0.85 L/min/m², p = 0.023) compared to non-PoPH patients. Targeted pulmonary vasodilator therapy was initiated in three patients with mean pulmonary arterial pressure ≥35 mmHg, with two severe cases successfully bridged to LT following demonstrable hemodynamic improvement. The 40 mmHg TTE threshold demonstrated robust diagnostic performance characteristics: 95.0 % sensitivity, 93.5 % specificity, 42.2 % positive predictive value, 99.7 % negative predictive value, with positive and negative likelihood ratios of 14.7 and 0.05, respectively. Conclusions: PoPH affects 4.74 % of LT candidates with portal hypertension using contemporary diagnostic criteria. Systematic TTE screening employing a 40 mmHg threshold for RVSP effectively identifies patients requiring further hemodynamic assessment, with exceptional negative predictive value enabling confident exclusion of clinically significant disease while minimizing unnecessary procedures. Early recognition coupled with targeted therapy successfully bridges selected patients to LT with excellent long-term outcomes