IYTE GCRIS Database (Izmir Institute of Technology)
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Hydrokinetic Power Potential Assessment of the Çoruh River Basin
No full textHydrokinetic power contributes to energy security by a sustainable and predictable power source, and its decentralized nature fosters economic development in local communities. Unlike large-scale hydropower projects, hydrokinetic power has lower environmental impacts, promoting technological innovation and supporting the transition to cleaner energy systems. Furthermore, it pledges to guarantee electricity in isolated regions where traditional power systems are not suited, enhancing energy accessibility. This study presents a method that combines the Soil and Water Assessment Tool (SWAT) with the Hydrologic Engineering Center's River Analysis System (HEC-RAS) to forecast the hydrokinetic power capacity of a basin. The research site chosen is the ; Ccedil;oruh River, a transboundary river basin with unavailable publicly accessible flow data. This method approximates the flow data utilizing the SWAT model, which relies on hydrological factors. Following the prediction of the flow data in the basin, the HECRAS model simulates the river's hydraulic conditions to estimate hydrokinetic energy potential. This integrated methodology provides a framework for optimizing hydrokinetic resources in diverse settings, guiding resource management, and sustainable energy planning. This study calculated theoretical hydrokinetic energy potential by considering flow velocity values. Results of the study indicated that the average flow velocity in the ; Ccedil;oruh basin reaches its maximum value of 0.99 m/s in spring and its minimum value of 0.69 m/s in summer, respectively. Based on the seasonal analysis of the integrated approach, the highest maximum theoretical hydrokinetic power density in the basin reaches 26 kW/m2 during the spring and in subbasins 5, 7, and 8. The average theoretical hydrokinetic power density is calculated as 0.28 kW/m2. Finally, the study presents several potential locations along the ; Ccedil;oruh River through GIS mapping, where small-scale hydrokinetic turbines could be installed as a viable option
Nonreciprocal Transmission Enabled by Time Modulation of Penetrable Metasurface Assisted by Surface Waves
No full textThis study introduces a novel approach to achieving nonreciprocal transmission by implementing time modulation to the bianisotropic metasurface. For the first time, we present the analytical solution of the excitation of anti-symmetric surface waves on penetrable metasurfaces depending on the excitation direction. Exploiting this finding, we numerically demonstrate asymmetric control of the transmission coefficient under a fast-time scale by employing solely time modulation. This approach lowers the complexity of the modulation scheme and implementation encountered in the space-time modulation technique. We develop and simulate a 3D unit cell model in the microwave domain, which forms a surface cavity that incorporates time-varying capacitors. The impedance transfer matrix method and harmonic balance numerical solutions are applied to the retrieved equivalent circuit for the numerical simulations. The results reveal optimized phase-coherent and incoherent nonreciprocal transmission at the significant isolation level ( >= 40 dB) for forward and backward transmissions. We discuss the consistency and discrepancies between numerical methods and consider the impact of the losses and nonlinearity on the metastructure performance. (c) 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) licens
Delignification of Corncob by Choline Chloride-Urea Deep Eutectic Solvent for Enzymatic Production of Xylooligosaccharides
No full textDeep eutectic solvent (DES) pretreatment was applied to corncob to obtain xylooligosaccharides (XOS) by enzymatic hydrolysis using xylanase. Based on the XOS titers in the hydrolysate, urea was the most effective among the hydrogen bond donors tested to couple choline chloride (ChCl). DES pretreatment at 130 °C for two hours with ChCl-Urea (molar ratio of 1:2) containing 40 % water, decreased lignin fraction from 12.8 % to 6.9 %, while 79 % of the xylan was retained in the pretreated corncob. The highest XOS production was obtained using 400 U/g xylanase at 60 °C, which yielded 12.0 g/L XOS with a low degree of polymerization (LDP-XOS). The total XOS yield based on the raw corncob was calculated as 14.4 %, 90 % of which was LDP-XOS. The cellulose-rich residual biomass could be hydrolyzed enzymatically to glucose with 65 % cellulose digestibility. The discarded biomass after hydrolyzes was 21.7 % of the raw material. The results showed that DES was a promising pretreatment for enhancing enzymatic XOS production. © 2024 Elsevier B.V
Magnetic Levitation-Based Miniaturized Technologies for Advanced Diagnostics
No full textTaking advantage of the magnetic gradients created using magnetic attraction and repulsion in miniaturized systems, magnetic levitation (MagLev) technology offers a unique capability to levitate, orient and spatially manipulate objects, including biological samples. MagLev systems that depend on the inherent diamagnetic properties of biological samples provide a rapid and label-free operation that can levitate objects based on their density. Density-based cellular and protein analysis based on levitation profiles holds important potential for medical diagnostics, as growing evidence categorizes density as an important variable to distinguish between healthy and disease states. The parallel processing capabilities of MagLev-based diagnostic systems and their integration with automated tools accelerates the collection of biological data. They also offer notable advantages over current diagnostic techniques that require costly and labor-intensive protocols, which may not be accessible in a low-resource setting. MagLev-based diagnostic systems are user-friendly, portable, and affordable, making remote and label-free applications possible. This review describes the recent progress in the application of MagLev principles to existing problems in the field of diagnostics and how they help discover the molecular- and cellular-level changes that accompany the disease or condition of interest. The critical parameters associated with MagLev-based diagnostic systems such as magnetic medium, magnets, sample holders, and imaging systems are discussed. The challenges and barriers that currently limit the clinical implications of MagLev-based diagnostic systems are outlined together with the potential solutions and future directions including the development of compact microfluidic systems and hybrid systems by leveraging the power of deep learning and artificial intelligence
Introducing Climate-Related Counterurbanisation: Individual Adaptation or Societal Maladaptation?
No full textClimate disruption today and anticipated future climate breakdown are reshaping demographic and spatial processes, with profound consequences for societies across the globe. Specifically, migration can become a key strategy to attempt to respond to and cope with environmental change. This paper seeks to make sense of one type of migration, counterurbanisation, in this climate breakdown era. It provides conceptual clarity to what is termed 'climate-related counterurbanisation' vis-`a-vis wider climate-induced migration and positions climate disruption within the counterurbanisation literature. Climate-related counterurbanisation is presented as a largely voluntary movement down the settlement hierarchy as a direct or indirect response to climate change, with positive representations of 'rurality' central to the relocation decision: individual adaptation. However, it is mediated by numerous geographically variegated and specific environmental, cultural, social and economic factors. Indeed, it may ultimately come to be seen more as maladaptation than adaptation. While moving from urban to rural may make sense at individual household level, such relocations can overall have much more negative impacts on host rural communities or the urban people left behind
Integration of Daylight Use and Analysis in Double Skin Facades: a Literature Review
No full textDouble skin facades (DSF) aim to save energy reducing the heat losses in buildings. They are visually appeal while allowing to use daylight efficiently. Such facade systems can reduce glare and distribute daylight evenly in the interior when compared to conventional facade systems. That is a result of cavities between two glass facades and locating sun shading elements in them, although this system provides a high level of transparency. As their primary purpose of application is to ensure thermal performance and ventilation, most studies in literature have focused on these. This study started with the hypothesis that studies examining daylight performance in DSFs are more limited than studies examining thermal performance and that daylight optimization methods are not used sufficiently in DSFs. In this context, the study aims to analyze studies focusing on daylight performance of DSFs. The review targets results of such current studies to guide future ones providing feedback knowledge. This may help to better technical developments in such facades and make them prevail in constructions or in retrofitting So, it contributes to literature in this sense. Recent studies are shown in tabulated form and interpreted in detail with graphics. considering their methodologies, daylight parameters and findings. Results show that the daylight parameter is one of the most important issues that architects or designers should consider from the moment they start the design, and they should make their designs based on the optimum penetration of daylight into the building. Consequently, this review presents that the use of daylight optimization has started to be used in recent studies dealing with DSFs. A DSF design can optimally get daylight into the interior can be made by using this method more frequently
Assessment of Groundwater Potential Using Geographic Information System Based Multi Criteria Decision Analysis Methods: Case Study of Panj Amu River Basin, Afghanistan
No full textAfghanistan, where water is the most important resource for energy production and the economy. The country still struggles with access to clean drinking water, and its main supply of drinking water comes from groundwater. Unfortunately, not much is known about the country's groundwater system. The assessment of groundwater potential and groundwater stability is crucial for sustainable water management, agricultural development, urban and rural water supply, and disaster mitigation. It supports environmental protection, economic development, public health, and conflict prevention by ensuring reliable and sustainable access to groundwater resources. In regions such as the Panj Amu River Basin, this identification is particularly important due to the high dependence on groundwater. Therefore, the thesis focuses on water budget, groundwater potential, availability, and the impact of various parameters on groundwater recharge of the PARB using the Analytical Hierarchy Process (AHP), Frequency Ratio (FR) and Evidential Belief Function (EBF) methods. Ten thematic layers including precipitation, geology, lineament density, drainage density, soil texture, land use and land cover, topographic wetness index, curvature, normalized difference vegetation index and slope gradient were used as influencing factors along with groundwater static level data, runoff and evapotranspiration for this research work. All geographic datasets were analyzed using the ArcMap environment and the required spatial data were obtained from various approved relevant online sources. The water balance analysis for the Panj Amu River Basin indicates that 1.887 billion cubic meters' infiltrates into the groundwater system annually. The total annual groundwater consumption by humans, livestock and agricultural activities amounts to 808.19 million cubic meters. Consequently, the annual net groundwater budget in the basin is 1.078 billion cubic meters, suggesting that the groundwater system in the PARB is currently sustainable. All three methods indicate high groundwater potential in sparsely v populated mountainous regions with high rainfall and permeable geology and soil conditions. The key regions include the northeast of Takhar, the east and southeast of Baghlan and the northwest and east (some parts of the Wakhan corridor) of Badakhshan have high groundwater potential. In general, the Panj Amu River Basin has moderate groundwater potential. Area Under the Curve (AUC) and Receiver Operating Characteristic (ROC) analysis were used to validate the study. The results show that the EBF methods has the highest efficiency with an AUC of 92.6%, followed by the FR method with 91.5% and the AHP model with 80.2%.Afganistan da su, enerji üretimi ve ekonomi için en önemli kaynaktır. Ülke hâlâ temiz içme suyuna erişim konusunda zorluk yaşamaktadır. Ülkenin ana içme suyu kaynağını yeraltısuları oluşturmaktadır. Ancak, ülkenin yeraltısuyu kaynakları hakkında yeterli bilgi mevcut değildir. Yeraltısuyu kaynakları potansiyelinin değerlendirilmesi ve sürdürülebilir su yönetimi, tarımsal kalkınma, kentsel ve kırsal su temini ve afetlerin azaltılması açısından çok önemlidir. Yeraltısuyu kaynaklarına güvenilir ve sürdürülebilir erişim sağlanmasıyla çevrenin korunması, ekonomik kalkınma, halk sağlığı ve çatışmalar önlenebilir. Panj Amu Nehri Havzası (PANH) gibi bölgelerde, yeraltısuyuna olan bağımlılığın yüksek olması nedeniyle bu kaynakların özelliklerinin bilinmesi önemlidir. Bu tez kapsamında, PANH'nın yeraltısuyu potansiyeli, kullanılabilirliği ve çeşitli parametrelerin yeraltısuyu beslenmesi üzerindeki CBS, AHP, FR ve EBF yöntemleri kullanılarak değerlendirilmiştir. Bu çalışmada, yağış, jeoloji, çizgisellik yoğunluğu, drenaj yoğunluğu, toprak dokusu, arazi kullanımı, arazi örtüsü, topografik nem indeksi, farklı bitki örtüsü indeksi ve eğim dahil olmak üzere on tematik katman ile birlikte, yeraltı suyu statik seviyeleri, akış ve buharlaşma-terleme verileri kullanılmıştır. Tüm coğrafi veri setleri ArcMap programı kullanılarak analiz edilmiştir. Tüm veriler onaylanmış çevrimiçi kaynaklardan elde edilmiştir. Panj Amu Nehir Havzası için yapılan su bütçesi, yeraltı suyu sistemine yılda 1,887 milyar metreküp sızdığını göstermektedir. İnsani tüketim, hayvancılık ve tarımsal faaliyetler tarafından tüketilen yıllık toplam yeraltı suyu miktarı 808,19 milyon metreküptür. Sonuç olarak, havzadaki yıllık net yeraltı suyu bütçesi 1.078 milyar metreküp olup bu da PANH'deki yeraltı suyu sisteminin şu anda sürdürülebilir olduğunu göstermektedir. Her üç yöntem de yüksek yağış alan, geçirgen jeolojik ve toprak koşullarına sahip seyrek nüfuslu dağlık bölgelerde yüksek yeraltı suyu potansiyeline vii işaret etmektedir. Kilit bölgeler arasında Takhar'ın kuzeydoğusu, Baghlan'ın doğu ve güneydoğusu ile Badakhshan'ın kuzeybatı ve doğusu (Wakhan koridorunun bazı kısımları) yüksek yeraltı suyu potansiyeline sahiptir. Eğri Altındaki Alan ve Alıcı Operatör Eğrisi (AUC-ROC) metodlarına göre, EBF metodu 92,6 ile en yüksek doğruluğa sahip olduğu, onu %91,5 ile FR'nin ve %80,2 ile AHP takip ettiği görülmüştür
Shallow Shell Ssta63 Resin: a Rapid Approach To Remediation of Hazardous Nitrate
No full textThis study examines the potential of Purolite Shallow Shell (TM) SSTA63 anion exchange resin for mitigating nitrate ion (NO3-) contamination in aqueous environments. Through systematic experimentation, including dosage optimization, pH dependency, kinetic and desorption studies, we investigate the sorption behavior and practical applications of the resin. Results indicate that the resin effectively removes NO3- ions, with maximum efficiency achieved within 10 minutes. When 0.025 g of resin was used, 75% of NO3- was removed, whereas with 0.05 g, 89% was removed, and with 0.1 g of resin, 95% was removed. At pH 1, approximately 50% of NO3- ions were removed, with removal efficiency reaching 97% between pH 4 and 10. Sorption isotherms affirm the suitability of the Langmuir model for the current investigation. The monolayer maximum sorption capacity (qmax) value was found to be 53.65 mg g-1. The resin demonstrates robust desorption capabilities using 0.1 M hydrochloric acid (HCl), effectively desorbing NO3- above 99%, indicating easy NO3- desorption and resin regeneration. The presence of coexisting ions such as chloride (Cl-), sulfate (SO42-), and phosphate (PO43-) showed a minimal impact on NO3- removal in individual binary mixtures, with efficiencies exceeding 93%, suggesting a strong selectivity of the resin towards NO3-. Purolite SSTA63 anion exchange resin exhibited a high affinity for NO3- ions, even over other competing ions, despite the general trend of ion exchange resins to favor ions with a higher atomic number and valence. Overall, this resin presents a promising solution for NO3- removal, with implications for water treatment and environmental remediation. This study explores the potential of Purolite Shallow Shell (TM) SSTA63 anion exchange resin for mitigating nitrate ion (NO3-) contamination in aqueous environments
Ankilozan Spondilit'in Moleküler ve İmmün Patogenezinin İncelenmesi
No full textKronik inflamatuvar ve otoimmün bir eklem hastalığı olan Ankilozan Spondilit (AS), özellikle genç erkeklerde görülen ve omurgayı etkileyen, sakroileit ve bambu omurga gibi belirgin lezyonlara yol açabilen bir durumdur. Hastalığın patofizyolojisi tam olarak anlaşılamamış olmasına rağmen, genetik faktörlerin, özellikle HLA-B27 genetik varyantının, büyük bir rol oynadığı bilinmektedir. Bu çalışmada, hastalarda HLA-B27 genotipinin, ERAP1 ve ERAP2 haplotiplerinin ve bu ikisinin ortak oluşturduğu HLA-B ile sunulan immünopeptidom profilinin, AS'nin gelişimindeki rollerinin daha iyi anlaşılması amaçlanmıştır. Çalışmada ERAP1 ve ERAP2 haplotiplerinin ankilozan spondilit (AS) hastalarındaki dağılımı türk popülasyonunda 200 hastalık seride gösterilmiş ve sağlıklı bireylerdeki dağılım ile kıyaslanmıştır. Hasta ve kontrol dağılımları farklılık göstermezken, literatürde AS için risk olarak tanımlanmamış olan haplotip-8 (Hap8) çalışmada hasta popülasyonunda en sık rastlanan haplotip olarak bulunmuştur. As hastalığıyla ilk ilişkilendirilmiş genotip olan HLA-B27 aleli için hasta ve kontrol gruplarında tiplendirme yapılmıştır. Hastalardaki sıklığı %85-90 rapor edilen HLA-B27 pozitifliği, çalışılan grupta %62 olarak bulunmuştur. Bununla birlikte HLA-B27 için negatif olan ancak As için risk aleli olan diğer alellerin oranı %18 olarak tespit edilmiştir. İlk belirlenen hasta grubunun içinden ERAP haplotipleri, HLA-B27 genotipleri ve klinik seyir özelliklerine göre seçilen ikinci hasta grubunda, MHC-I ile hücre yüzeyinde sunulan peptid havuzu saptanmış ve veritabanlarında taranmıştır. Bakteri, virüs ve fungus peptidleriyle dizi benzerliklerine ve immünojenite veritabanı skorlarına dayanılarak immünojenik/artritojenik olarak moleküler kenetlenme (docking) çalışmaları için aday peptidler tanımlanmıştır. Bu veriler ışığında peptidlerin kenetlenme çalışmalarının ayrıntılandırılması sonrası ERAP haplotipleri-HLA-B alt-tipleri- immünojenik aday peptid ilişkisinin kurulması ve in vitro immünojenite çalışması aday peptidlerinin belirlenmesi hedeflenecektir