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Removal of Ni(II), Cu(II), Pb(II), and Cd(II) from Aqueous Phases by Silver Nanoparticles and Magnetic Nanoparticles/Nanocomposites
No full texthe intake of heavy metals into the body, even at very low concentrations, may cause a decrease in central nervous system functions; deterioration of blood composition; and liver, kidney, and lung damage. Therefore, heavy metal ions must be removed from water. In this study, silver, magnetic iron/copper, and iron oxide nanoparticles were synthesized using Lathyrus brachypterus extract and then Fe/Cu-AT, Fe3O4-AT, Fe/Cu-CS, and Fe3O4-CS magnetic nanocomposite beads were synthesized using alginate and chitosan. The removal of Cd(II), Pb(II), Ni(II), and Cu(II) ions from aqueous phases using synthesized nanoadsorbents was investigated by single and competitive (double and quaternary) adsorption techniques. The kinetic usability of the magnetic iron oxide chitosan (Fe3O4-CS) nanocomposite beads with the highest removal efficiency was evaluated. Based on experimental results, the order of removal was found to be 98.39, 75.52, 51.54, and 45.34%, and it was listed as Pb(II) > Cu(II) > Cd(II) > Ni(II), respectively. The Dubinin-Radushkevich, Freundlich, Langmuir, and Temkin isotherm models were used, and experimental results revealed that the experimental data fit the Langmuir model better. The maximum adsorption capacities (qm) obtained from the Langmuir isotherm model of Fe3O4-CS were found to be 8.71, 23.75, 18.57, and 12.38 mg/g for Ni(II), Pb(II), Cu(II), and Cd(II) ions, respectively. When the kinetic data were applied to the Lagergren, Ho-McKay, and Elovich models, it was observed that the adsorption kinetics mostly conformed to the Ho-McKay second-order rate equation. The binary and quaternary competitive adsorption data showed that Fe3O4-CS were selective toward Cu(II) and Pb(II). The reusability of the Fe3O4-CS nanoadsorbent was performed as three cycles with the same concentration. The adsorption capacities were found to be 95.81, 70.65, 50.50, and 42.75%, in turn for Pb(II), Cu(II), Cd(II), and Ni(II) ions after three cycles, which revealed that the Fe3O4-CS nanoadsorbent can be used after three cycles without losing its efficiency
Analyses of L-Type Corner Joints Connected with Auxetic Dowels for Case Furniture
No full textTests were carried out to develop and manufacture various types of auxetic dowels using 3D printing technology. These dowels were then used to connect L-type corner joint specimens for case furniture, and their strength and stiffness were analyzed through experimental, theoretical, and numerical means. In the scope of the study, eight different types of auxetic dowels including two inclusion types, two inclusion sizes, and two dowel hole diameters, as well as a reference non-auxetic dowel, were designed. Accordingly, a total of 180 specimens that included 10 replications for each group were tested; 90 were tested under tension and the remaining 90 were tested under compression. The results demonstrated that the assembly force required for the corner joints connected with auxetic dowels was significantly lower compared to non-auxetic dowels. Furthermore, the numerical and theoretical analyses yielded similar outcomes in this study. Both analyses revealed that the dowels used to connect the corner joints experienced substantial stresses during mounting and bending, ultimately leading to their failure. Upon concluding the test results, it was observed that the corner joints connected with dowels featuring rectangular inclusions exhibited superior performance when compared to those with triangular inclusions. In light of these findings, it can be concluded that further enhancements are necessary for auxetic dowels with rectangular inclusions before they can be utilized as alternative fasteners for traditional dowels
Molecular and in silico analyses of SYN III gene variants in autism spectrum disorder
No full textBackground: Defects in neurotransmission and synaptogenesis are noteworthy in the pathogenesis of ASD. Synapsin III (SYN III) is defined as a synaptic vesicle protein that plays an important role in synaptogenesis and regulation of neurotransmitter release and neurite outgrowth. Therefore, SYN III may associate with many neurodevelopmental diseases, including ASD. Aim: The aim of this study was to investigate whether the SYN III gene -631 C > G (rs133946) and -196 G > A (rs133945) polymorphisms are associated with susceptibility to ASD. Methods: SYN III variants and the risk of ASD were investigated in 26 healthy children and 24 ASD children. SYN III gene variants were genotyped by PCR–RFLP methods. The differences in genotype and allele frequencies between the ASD and control groups were calculated using the chi-square (χ2). We analysed the SYN III gene using web-based tools. Results: Our results suggest that the presence of the AA genotype of the SYN III -196 G > A (rs133945) polymorphism affects the characteristics and development of ASD in children (p = 0.012). SYN III -631 C > G (rs133946) polymorphism was not associated with ASD (p = 0.524). We have shown the prediction of gene–gene interaction that SYN III is co-expressed with 17 genes, physical interaction with 3 genes, and co-localization with 12 genes. The importance of different genes (SYN I, II, III, GABRD, NOS1AP, GNAO1) for ASD pathogenesis was revealed by GO analysis. Conclusion: Considering the role of SYN III and related genes, especially in the synaptic vesicle pathway and neurotransmission, its effect on ASD can be further investigated
Antimicrobial and Antioxidant Activities of Extracts of Euphorbia rigida Bieb
No full textThe aim of this study was to determine antioxidant and antimicrobial activities of extracts of the Euphorbia rigida (Bieb.) plant which was extracted by using water, acetone, methanol, hexane and chloroform solution. Antimicrobial activity was determined by disc diffusion method against Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans. Antioxidant activity was determined by using β-carotene-linolenic acid, DPPH method, metal chelating activity, Cuprac and by evaluating the content of total phenolic compounds. Total antioxidant activities of E. rigida plant extracts at 50 and 100 μg/ml concentrations were compared against standard antioxidant activities such as BHT, α-tocopherol and quercetin activity. All extracts from E. rigida, except the chloroformic extract, showed antimicrobial activity against P. aeruginosa. However no activity was found against S. aureus and C. albicans. Antioxidant activities were found to be close to those of synthetic antioxidants such as BHT and α-tocopherol. The results indicate that E. rigida plant extracts can be used as a new and alternative antimicrobial agent against P. aeruginosa. It can also be argued that acetone and hexane extracts of E. rigida have the potential of becoming a natural antioxidant source. Moreover, all extracts from E. rigida might have important industrial, biotechnological, medical, agricultural, ecologial and economic potential
Milk lactose removal by β-galactosidase immobilized on eggshell membrane
No full textEggshell membrane (ESM) is used in immobilization studies due to its large surface area, non-toxicity and biodegradability. In this study, β-galactosidase was immobilized on ESM using the adsorption and cross-linking method. The interactions between enzyme and ESM after immobilization were determined by ATR-FTIR (attenuated total reflection fourier transform infrared spectroscopy) and SEM (scanning electron microscope). The optimum temperature of the free enzyme was found to be 35 °C, and this value was 45 °C for the immobilized enzyme. Immobilized enzyme managed to retain more than 50% of its activity after 8 reuses. In the lactose removal experiment from milk, the highest reaction efficiency was found as 55.8% under specified optimization conditions for β-galactosidase immobilized ESM after 3 h. Due to the microfiber protein structure of the ESM, it has improved enzyme stability properties, as a result of the multi protein–protein interactions formed after the immobilization between the proteins in the ESM and the enzyme molecules
Evidence of Insulin-Sensitizing and Mimetic Activity of the Sesquiterpene Quinone Avarone, a Protein Tyrosine Phosphatase 1B and Aldose Reductase Dual Targeting Agent from the Marine Sponge Dysidea avara
No full textType 2 diabetes mellitus (T2DM) is a complex disease characterized by impaired glucose homeostasis and serious long-term complications. First-line therapeutic options for T2DM treatment are monodrug therapies, often replaced by multidrug therapies to ensure that non-responding patients maintain target glycemia levels. The use of multitarget drugs instead of mono- or multidrug therapies has been emerging as a main strategy to treat multifactorial diseases, including T2DM. Therefore, modern drug discovery in its early stages aims to identify potential modulators for multiple targets; for this purpose, exploration of the chemical space of natural products represents a powerful tool. Our study demonstrates that avarone, a sesquiterpene quinone obtained from the sponge Dysidea avara, is capable of inhibiting in vitro PTP1B, the main negative regulator of the insulin receptor, while it improves insulin sensitivity, and mitochondria activity in C2C12 cells. We observe that when avarone is administered alone, it acts as an insulin-mimetic agent. In addition, we show that avarone acts as a tight binding inhibitor of aldose reductase (AKR1B1), the enzyme involved in the development of diabetic complications. Overall, avarone could be proposed as a novel natural hit to be developed as a multitarget drug for diabetes and its pathological complications
Association of Vitamin D and Secondary Infection in COVID-19
No full textGiriş: D vitamini sitokin salınımı, inflamasyon, doğal ve edinsel bağışıklığın modülasyonunda görev yapmaktadır. Pandeminin başların- da SARS-CoV-2’ye bağlı gelişen akut respiratuvar distres sendromu veya diğer organ hasarına neden olan hiperinflamatuvar yanıtın D vitamininin yeterliliği ile modüle edilebileceği sıkça tartışılmıştır. D vitamininin; mortalite, yoğun bakım yatış gün sayısı, hastalık ciddiye-ti, organ hasarı gibi birçok durum ile de ilişkisi araştırılmıştır fakat hastalığın seyri sırasında ortaya çıkan sekonder infeksiyonlar üzerine etkisi konusunda bilgiler sınırlıdır. Bu çalışmada D vitamininin COVID-19 hastalığı seyri sırasında ortaya çıkan sekonder infeksiyonlar ile ilişkisini ortaya koymak amaçlanmıştır.
Materyal ve Metod: COVID-19 pandemi servisine COVID-19 tanısı ile yatarak tedavi gören hastaların tıbbi kayıtları retrospektif olarak değerlendirildi.
Bulgular: Çalışmaya 181 hasta dahil edildi. 25(OH)D vitamini ortalaması 18.76 ± 9.82 ng/mL olarak bulundu. 25-hidroksi D vita-minin cinsiyet, hastalık şiddeti, mortalite, mekanik ventilasyon ihtiyacı ve semptomların varlığı ile karşılaştırıldığında istatistiksel olarak anlamlı bir fark saptanmadı (p> 0.05). Hastaların hastane yatışları boyunca olan tıbbi verileri incelendi ve %14.9’unda (n= 27) sekonder infeksiyon saptandı. 25-hidroksi D vitamini ile sekonder infeksiyon varlığı karşılaştırıldığında ise sekonder infeksiyon gelişenlerin 25(OH)D vitamini düzeyi düşük bulundu ve bunun istatistiksel olarak anlamlı olduğu tespit edildi (p= 0.016). ROC analizi ile yapılan değerlendirme sonucunda 25-hidroksi D vitamininin COVID-19 hastalarında pozitif kültür sonucunu öngörmede tanısal değeri olduğu görüldü (AUC= 0.771, %95 Güven aralığı= 0.612-0.810, p= 0.003, p< 0.05).
Sonuç: D vitamini immün sistem üzerindeki etkileri nedeniyle COVID-19 hastalığında önemli bir tartışma konusu olmaya devam ederken, düşük D vitaminin COVID-19 seyrinde gelişen sekonder infeksiyon riskini arttırdığı ve bu durumun prognoza etkisinin olabileceği unutulmamalıdır.Introduction: Vitamin D plays a role in the modulation of cytokine release, inflammation, innate and adaptive immunity. It has been frequently discussed that the hyperinflammatory response that causes acute respiratory distress syndrome or other organ damage due to SARS-CoV-2 at the beginning of the pandemic can be modulated by the adequacy of vitamin D. The relationship of vitamin D with many conditions such as mortality, number of intensive care unit stays, disease severity, and organ damage has been investigated, but the information on its effect on secondary infections that occur during the course of the disease is limited. In this study, it was aimed to reveal the relationship of vitamin D with secondary infections that occur during the course of COVID-19 disease.
Materials and Methods: Medical records of patients hospitalized in the COVID-19 pandemic service with the diagnosis of COVID-19 were evaluated retrospectively.
Results: One hundred eighty-one patients were included in the study. The mean of 25(OH) vitamin D was found to be 18.76 +/- 9.82 ng/mL. When 25-hydroxy vitamin D was compared with gender, disease severity, mortality, need for mechanical ventilation and presence of symptoms, no statistically significant difference was found (p> 0.05). The medical data of the patients during their hospitalization were analyzed and secondary infection was detected in 14.9% (n= 27). When 25-hydroxy vitamin D and the presence of secondary infection were compared, the 25(OH)D vitamin level of those with secondary infection was found to be low and this was found to be statistically significant (p= 0.016). As a result of the evaluation made by ROC analysis, 25-hydroxy vitamin D was found to have a diagnostic value in predicting positive culture results in COVID-19 patients (AUC= 0.771, 95% Confidence Interval= 0.612-0.810, p= 0.003, p< 0.05).
Conclusion: While vitamin D continues to be an important topic of discussion in COVID-19 disease due to its effects on the immune system, it should not be forgotten that low vitamin D increases the risk of secondary infection developing in the course of COVID-19 and this may have an impact on prognosis
Current and future prospective for battery controllers of solar PV integrated battery energy storage systems
No full textSolar photovoltaic (PV) microgrids have gained popularity in recent years as a way to improve the stability of intermittent renewable energy generation in systems, both off-grid and on-grid, and to meet the needs of emergency settings during natural catastrophes. Over the last several decades, researchers have been interested in improving the efficiency of photovoltaic (PV) systems. Solar-battery charge controllers based on various algorithms are continuously and intensively employed to improve energy transfer efficiency and reduce charging time. This paper presents state-of-the-art solar photovoltaic (PV) integrated battery energy storage systems (BESS). An overview of and motivations for PV-battery systems is initially introduced, followed by the survey methodology and its contributions. In addition, this study classifies residential solar PV systems and battery charge controllers with their corresponding references in the review structure, which also provides details on battery charger topologies. Subsequently, an analytical review of the PV-Battery charge controller and the failure probability of such systems is discussed to determine the system components that mostly fail and their importance in the system. Finally, recommendation amendments to the existing charge controller that potentially contribute to increasing the system efficiency, reducing the failure probabilities, and reducing the cost are presented as future design concepts for the entire system
Effect of Foam-mat Drying on Bioactive, Powder and Thermal Properties of Carrot Juice Powders
No full textFoam-mat drying is a promising method due to involvement of proteins as foaming agent which acts like a wall material wrapping around bioactives and retards their degradation. In this study, powder properties of foam-mat dried carrot juice powders including 15% egg albumen (EA) and 15% egg albumen+ 10% whey protein isolate (WPI) during 90 days of storage at room conditions were evaluated by means of physical, chemical, thermal (DSC and TGA) and microstructural (SEM) analyses. The powder flow properties (wettability, hygroscopicity, degree of caking, Carr index and Hausner ratio) have been significantly affected from the moisture uptake during storage; however, powder flow properties of 15% EA+ 10% WPI powders were found to be better than 15% EA powders as it was also confirmed by particle diameter distributions that remained the same before and after the storage period. Besides, the total antioxidant, phenolic and carotenoid contents of 15% EA+ 10% WPI carrot powder was found comparably higher than 15% EA powders due to possible encapsulating mechanism of whey proteins. In addition to delaying of physical and chemical deteriorations in powders with WPI incorporation, thermal stability of the foam-mat dried carrot juice powders was also improved in 15% EA+ 10% WPI powder
Determination of Exogenous Adrenaline Levels in Patients Undergoing Cardiopulmonary Resuscitation
No full textCore-shell quantum dot ZnS/CdSe screen-printed electrodes were used to electrochemically measure human blood plasma levels of exogenous adrenaline administered to cardiac arrest patients. The electrochemical behavior of adrenaline on the modified electrode surface was investigated using differential pulse voltammetry (DPV), cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). Under optimal conditions, the linear working ranges of the modified electrode were 0.001-3 μM (DPV) and 0.001-300 μM (EIS). The best limit of detection for this concentration range was 2.79 × 10-8 μM (DPV). The modified electrodes showed good reproducibility, stability, and sensitivity and successfully detected adrenaline levels