24 research outputs found
Role of pyroptosis in COVID-19
Aim: In this study, we aimed to investigate the relationship between gasdermin-D, caspase-1, IL-1β and NLRP3, biomarkers that play an important role in COVID-19, and pyroptosis.
Material and Methods: This study was carried out with 58 participants, 28 (48.28%) of whom were diagnosis with COVID-19, and 30 (51.72%) of whom were healthy volunteers (control group).
Results: There were no statistically significant differences between the gasdermin-D, caspase-1, IL-1β, and NLRP3 levels as a result of all statistical comparisons performed. However, IL-1β values both during the discharge period and during the hospitalization period were considerably higher than those of the control group. At the discharge period, IL-1β values of the patients with severe COVID-19 category had higher than moderate patients, and the patients with moderate than the patients with mild patients.
Conclusion: It was observed that IL-1β, which is one of the cytokines released as a result of cell death in the pyroptosis mechanism, was higher in the COVID-19 patients in both the hospitalization and discharge periods compared to the control group. Although not statistically significant these results could support the relationship between pyroptosis and COVID-19
Model based process optimization of enhanced wastewater treatment plants
Avrupa Birliği’ne uyum sürecinde ele alınan atık sorunu kapsamında, alıcı ortamlara yapılacak deşarjlarda konvansiyonal parametrelerin yanısıra azot ve fosfor (besi maddesi) parametrelerinin de belli standart değerlerin altına indirilmesi gerekli hale gelmiştir. Bu nedenle, “Kentsel Atıksu Arıtımı Yönetmeliği, 2006” ile uyum sürecinde olan ülkemizde azot ve fosfor standartları mevzuatımıza dâhil edilmiştir. “Kentsel Atıksu Arıtımı Yönetmeliği, 2006” kapsamında mevcut tesislerin besi maddesi giderimine yönelik olarak geliştirilmesi, yeni kurulacak tesislerin ise besi maddesi giderecek şekilde en uygun arıtma teknolojisi kavramı çerçevesinde boyutlandırılması gereklidir. Besi maddesi giderimine yönelik en uygun arıtma teknolojisi biyolojik prosesler, bunlar arasında en ekonomik çözüm ise aktif çamur sistemleri olarak tanımlanmaktadır. Bu çalışma aktif çamur tesislerinin, Avrupa Birliği normlarında performansını sağlayabilecek optimum tasarım ve işletme süreçlerinin değerlendirilmesini amaçlamaktadır. Bu kapsamda, bir örnek olarak ele alınan İstanbul Su ve Kanalizasyon İdaresi (İSKİ) Paşaköy İleri Biyolojik Atıksu Arıtma Tesisi’nde mevcut durumda atıksu karakterizasyonu ve sistem performansı deneysel olarak belirlenmiş, elde edilen bilgiler kullanılarak sürekli kullanıma uygun olacak model-bazlı tasarım ile işletme simülasyon programları hazırlanmış ve işletme optimizasyonu çerçevesinde çıkış besi maddesi konsantrasyonlarının düşürülmesi amacıyla işletme senaryoları oluşturularak önerilerde bulunulmuştur. Yürütülen senaryo analizleri ile, havalandırma tanklarındaki çözünmüş oksijen seviyelerinin uygun ayarlanması, tesisin geri devir denitrifikasyonu prensibi yerine A2O veya UCT tipi sistem şeklinde işletilmesi ile sistem veriminin arttırılabileceği ve dolayısıyla çıkış besi maddesi konsantrasyonlarının azaltılabileceği belirlenmiştir. Anahtar Kelimeler: İleri biyolojik atıksu arıtma tesisi, atıksu karakterizasyonu, model-bazlı tasarım, işletme optimizasyonu.The Urban Wastewater Treatment Directive published in the Official Gazette No. 26047 of 08.01.2006 was adapted from the “The Council Directive (91/271/EEC)” concerning urban waste-water treatment was accepted in European Union Countries, which imposes enforcements about the collection and treatment of wastewater. This directive requires that also nitrogen and phosphorus (nutrients) to be removed together with the conventional parameters. In this context, it is very important to follow and apply the technological advances while the harmonization of legislations in Turkey with European Union Standards. Mathematical models are frequently used for the design and optimum operation of wastewater treatment systems. In order to use the activated sludge models for the process design and control, it is crucial to understand the behavior of complex biological reactions under steady and dynamic conditions. The initial step for the use of models should be, a model calibration according to the data obtained from the treatment plant and an analysis of the behavior of the treatment plant under dynamic influent and environmental conditions (Vanrolleghem et al., 2003). After the calibration of the prepared model according to the operational conditions of the treatment plant, the model can be used for the optimization of the plant, meeting the effluent quality standards, minimizing operational costs and for developing appropriate process control strategies. On the other hand the effect of changes in the process conditions on the model stability should be taken into consideration (Insel et al., 2007). The aim of this study was to evaluate the optimum design and operational criteria of advanced biological wastewater treatment plants by applying international monitoring and evaluation mechanisms that will increase the performance to norms required in the European Union. Accordingly, İSKİ Paşaköy Advanced Biological Wastewater Treatment Plant (ABWWTP) was chosen as a model plant and in the first stage on influent wastewater characterization, chemical oxygen demand (COD) fractionation and performance of the activated sludge system were experimentally determined. In the second stage, using the dimensions of the İSKİ Paşaköy ABWWTP units and the experimentally determined operational parameters, model calibration studies were conducted. On this context, theoretical parameters of model-based design and operational simulation programs applied for the plant were evaluated. In the last stage of the study, for operational optimization, according to the results obtained from the experimental and simulation studies conducted at İSKİ Paşaköy ABWWTP, operational scenarios were developed and suggestions were made. In the scenario analysis reduction of effluent phosphorus and total nitrogen concentration was aimed and the effect of (i) the aeration system control, (ii) recycle denitrification (iii) influent VFA concentration was analyzed and the effect of (iv) different system configurations was evaluated. The results of statistical data analysis of wastewater characterization studies conducted at İSKİ Paşaköy Advanced Biological Wastewater Treatment Plant aiming nitrogen and phosphorus removal revealed that due to low influent Chemical Oxygen Demand (COD), Total Kjeldahl Nitrogen (TKN), Total Phosphorus (TP) and Volatile Fatty Acids (VFA) concentrations, high efficiencies of biological phosphorus removal was not achievable. According to the scenario analysis performed for the treatment plant it has been concluded that it is possible to increase the removal efficiency of the system and achieve lower effluent total nitrogen and phosphorus concentrations by setting the dissolved oxygen levels to appropriate levels and operating the systems as an A2O or a UCT type system instead of a recycle denitrification system. It has been concluded that if the scenario analyses were applied it is not possible to meet the European Union Effluent Quality Standard of 1.0 mg/l for the phosphorus parameter. Experimental and model based studies have to be conducted for the installation of a fermentation process together with different system configurations that are required to meet the effluent quality standard by biological treatment. Keywords: Paşaköy wastewater treatment plant, wastewater characterization, model based optimization, process control
Pretreatment of polyester microfiber materials and investigation of HT dyeing parameters
Bu çalışmada, polyester mikrolitlerinin ön terbiye ve HT boyama parametrelerinin incelenmesi amaçlanmıştır. Giriş bölümünde konunun amacı ve içeriği hakkında genel bilgi verilmiştir. İkinci bölümde, mikrolitlerin üretimi, kullanım özellikleri, ön terbiye ve HT boyama işlemleriyle ilgili bilgiler verilmiştir. Üçüncü bölümde, deneysel işlemlerde kullanılan kumaşlar, boyarmaddeler, kimyasallar, deneylerde kullanılan cihazlar ve uygulama metodları verilmiştir. Dördüncü bölümde, deneysel çalışmanın sonuçlan hakkında tartışılmış ve son bölümde ise konu ile ilgili toplu bir değerlendirme yapılmıştır.In this study it is aimed to investigate the pretreatment and HT dyeing parameters of polyester microfibers. An introductory information about the content and coverage of this dissertation is given in the first part. More detailed account of the usage and processing characteristics of microfibers is made followed by some aspects of HT dyeing of polyester microfibers in the second part. In the experimental chapter, initially the equipment used are introduced then a detailed information on the chemicals used in the experiments is given in addition to the method of the investigation. The results obtained from the experimental work are discussed before the final section in which an overall comment on the subject is made.Ete Mensucat A.Ş
Analiza geometryczna trójwymiarowych kompozytów rdzeniowych typu „sandwich”
The variability of the internal geometry parameters, such as the waviness of yarns, cross sections of yarns and local fibre volume fraction of 3-dimensional (3D) integrated woven core sandwich composites affects their mechanical properties. The objective of this study was to define the geometrical and structural parameters of 3D integrated woven core sandwich composites, including the fold ratio of pile threads, the fabric areal weight and the fibre volume fraction by changing the core thickness of 3D sandwich core fabric. 3D fabrics with different core thicknesses were used for reinforcement. It was confirmed that the pile fold ratio, slope angle and pile length increase with an increase in the core thickness of the fabric. The difference between the calculated and experimental areal weights of fabrics was in the range of 5-13%. A novel approach was also presented to define the fibre volume fraction of 3D woven core sandwich composites.Zmienność parametrów geometrii wewnętrznej, takich jak: falistość przędz, przekroje przędz i udział objętościowy frakcji włókien wpływa na właściwości mechaniczne trójwymiarowych kompozytów rdzeniowych typu „sandwich”. Celem badania było określenie parametrów geometrycznych i strukturalnych trójwymiarowych kompozytów rdzeniowych typu „sandwich”, w tym współczynnika pofałdowania nitek, masy powierzchniowej tkaniny i udziału objętościowego frakcji włókien, poprzez zmianę grubości rdzenia. Do wzmocnienia zastosowano tkaniny 3D o różnych grubościach rdzenia. Potwierdzono, że m.in. współczynnik pofałdowania wzrasta wraz ze wzrostem grubości rdzenia. Różnica między obliczoną i eksperymentalną masą powierzchniową tkanin mieściła się w zakresie 5-13%
Influence of Stitching Parameters on Tensile Strength of Aramid/Vinyl Ester Composites
Stitching process is used to provide structural integrity and through-the-thickness reinforcement in the composite materials. In this study, the effect of sewing parameters on tensile strength in stitched composite laminates was examined. In the production of composite laminates, Twaron T-750 type plain weave fabric was used as reinforcement material and a Polives 702 Bisphenol-A type epoxy based vinyl ester as resin. The effects of stitch density and stitch direction or stitch pattern on tensile strength of composite samples were studied and, as a result of the experiments, it was observed that higher tensile strength occurs with low stitch densities in stitched laminates.DOI: http://dx.doi.org/10.5755/j01.ms.19.1.3829</p
Quasi-static behavior of three-dimensional integrated core sandwich composites under compression loading
In the current study, the effect of the thickness and the foam density in three-dimensional integrated woven sandwich composites on quasi-static properties was investigated. For this purpose, produced samples were subjected to uniaxial flatwise compression tests and their compression strength and moduli were determined. Obtained results were optimized by taking core thickness, foam density and panel weights into consideration. Damages that occurred on the tested samples were reported. When compared to conventional foam core sandwich composites, it was found that three-dimensional integrated sandwich composites have better compression properties and due to the fact that the pile yarns in the core and the foam support each other.status: publishe
Static behavior of three-dimensional ıntegrated core sandwich composites subjected to three-point bending
In the current study, the effect of the thickness and the foam density in three-dimensional integrated woven sandwich
composites on quasi-static mechanical properties under three-point bending was investigated. Bending modulus and core shear modulus were determined by subjecting the samples, which were cut with varying span lengths according to their core thicknesses, to three-point bending test. Obtained results were optimized by taking core thickness, foam density and panel weights into consideration. Damages that occurred on the tested samples were reported. When compared to conventional foam core sandwich composites, it was found that three-dimensional integrated sandwich composites have superior mechanical properties and due to the fact that the pile yarns in the core and the foam support each other, contrary to conventional sandwich composites no catastrophic core breakage occurs under load, thus the load bearing capacity of the structure is sustained.status: publishe
Effect of structural hybridization on ballistic performance of aramid fabrics
This article presents an investigation regarding the ballistic performance of hybrid panels formed by combining woven and unidirectional (UD) para-aramid fabrics. For this purpose, hybrid panels are formed by combining woven and UD para-aramid fabrics with different ply ratios. The hybrid panels formed in this way are subjected to ballistic tests according to National Institute of Justice (NIJ) standard. The results show that hybrid panels present 4.48% less trauma depth as compared to 100% woven fabric panels and 3% less trauma diameter as compared to 100% UD fabric panels. Furthermore, 13.9% less energy is transmitted to the back side of hybrid panels as compared to 100% UD fabric panels. The energy absorbed per unit weight in hybrid panels is 8.48% more as compared to 100% woven fabrics. Additionally, in wet conditions, less trauma depth of hybrid panels is observed as compared to both 100% woven and 100% K-Flex UD fabric panels. No significant difference is realized in trauma diameter between hybrid panels and 100% woven fabric panels in wet conditions. However, 3.25% less trauma diameter is noticed in hybrid panels as compared to 100% UD fabric panels
Study of dynamic compressive behaviour of aramid and ultrahigh molecular weight polyethylene composites using Split Hopkinson Pressure Bar
In this paper, high strain rate compression properties of aramid and ultrahigh molecular weight polyethylene composites in the out-of-plane direction are tested at room temperature on a Split Hopkinson Pressure Bar apparatus. Tests were conducted on composites reinforced with woven or Uni-Directional (UD) fabrics made from aramid or ultrahigh molecular weight polyethylene as well as on composites reinforced with hybrid reinforcement. The strain rate is varied in the tests by changing the projectile shooting pressure. Four different pressures 2, 4, 6 and 8 bar were selected to change the strain rate. Stress-strain and energy absorption behaviour of eight type of samples were noted. Hybrid samples showed better performance in the energy absorption compared with other samples. © SAGE Publications