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Tunable fano resonance in mid-infrared region based on asymmetric graphene nanoribbon arrays
No full textAn asymmetric graphene nanoribbon structure is presented to reach plasmonic Fano resonance in mid-infrared region when illuminated by a TM polarized light. Each mode of the Fano resonance is connected to the resonance mode occurred around each of nanoribbons with different width in the structure. Numerical studies show that the position and amplitude of the double resonances can be actively adapted via geometrical modification of the graphene structure or altering the doping level. Moreover, simulation results show highly remarkable enhancement in normalized electric field intensity for the asymmetric graphene structure compared to its symmetric counterparts. This feature is advantageous for construction of high sensitivity instruments such as sensors or filters
Investigation of the constituents of commercially available toothpastes
No full textObjectives: Toothpaste plays a pivotal role in oral and dental hygiene. This cross-sectional study not only investigates the constituents of toothpastes available in the market and their frequency across different brands but also delves into the potential side effects, irritations, or unfavourable outcomes of these constituents, emphasizing the broader health and environmental implications.
Methods: The largest of the five major chain markets in each district of Istanbul was visited, and adult toothpastes were included in this study. All the constituents that make up the toothpaste were individually recorded in an Excel database. Subsequently, literature regarding the purposes, toxic and potential side effects of each ingredient was gathered using databases such as Google Scholar, PubMed and ScienceDirect. The percentages of these ingredients' occurrence among all the toothpastes were calculated, and the ingredients were categorized into 15 distinct groups based on their usage purposes.
Results: There were 160 different varieties of toothpaste belonging to 19 different brands on the market shelves. Although a total of 244 different ingredients were identified, only 78 of them were included in the study. Among the analysed toothpaste types, 105 of them were found to contain 1450 ppm fluoride, whilst 26 toothpaste variants were discovered to have fluoride levels below this value. Among the various ingredients analysed, particular attention was drawn to commonly debated compounds in oral care products. Specifically, titanium dioxide was found in 68% (n = 111) of the varieties, sodium lauryl sulphate in 67% (n = 108) and paraben in 2% (n = 4), respectively.
Conclusion: Whilst certain ingredients may raise concerns for potential side effects and health considerations within the human body, the toothpaste has long been regarded as an indispensable tool for maintaining optimal oral and dental health. However, gaining a deeper understanding and conducting research on each constituent that comprises the toothpaste, as well as raising awareness in this regard, holds significant importance for human health
Yeminli mali müşavirlerin tasdik işlemlerinden kaynaklanan müteselsil sorumluluğu ve rücu ilişkileri
No full textYMM’ler, 213 S.K.’nın mük. 227. madde ve 3568 S.K.’nın 12. madde hükümleri uyarınca;
tasdik işlemleri sonucu meydana çıkan vergi ziyaı, ceza ve gecikme faizlerinden dolayı
mükellefle birlikte müştereken ve müteselsilen sorumlu tutulmuşlardır. YMM’lere
yüklenen müteselsil sorumluluğun vergi ve borçlar hukuku arasında bir yerde durması
sebebiyle, sorumluluk uygulaması meslek mensubunun aleyhine olabilecek birçok husus
içermektedir. Çalışma kapsamında, bu özel sorumluluk halinin aydınlatılması amacıyla
Yargı kararlarında meslek mensuplarının müteselsil sorumlu tutulması için bir ölçüt olarak
belirlenen mesleki özen kavramı üzerinde durulmaktadır.
YMM’lerin sorumluluk sınırlarının saptanması; hem kendilerinin hem mükelleflerin 6098
S.K. kapsamında birbirlerine rücu hakkı ve bu hakkın kullanılmasına yönelik taleplerini de
etkilemektedir. Şartlar oluştuğu takdirde; mükellefin, görevini layıkıyla yerine getirmeyen
YMM’ye karşı ve YMM’nin de çeşitli sebeplerle ödemek zorunda kaldığı tasdik
işleminden kaynaklanan vergi ziyaı, ceza ve gecikme faizlerinden dolayı mükellefe iç
ilişkide rücu etmesi mümkündür. Bu tür iç ilişkiler bir özel hukuk ilişkisi olması sebebiyle,
şayet taraflar arasındaki sözleşmede tahkim şartı varsa hakem kararıyla, yok ise adli yargı
organlarında çözülecektir. YMM ve mükellefin birbirlerine yönelttikleri rücu taleplerinde tahkim heyeti yahut hâkim
sorumluluğu paylaştırırken; özellikle YMM’nin mesleki özen kavramı üzerinde duracak,
olayın bütün durum ve koşulları ile kusurun ağırlığını değerlendirerek sorumluların
olaydaki rollerini hakkaniyet gereğince dikkate alacaktır.Sworn-in Certified Public Accountants, Tax Procedure Law No. 213 Pursuant to the
provisions of article 227 and article 12 of the Law of Accounting Professional Numbered
3568; The sworn-in certified public accountant and the taxpayer are jointly and severally
liable for the resulting tax loss, penalty and delay interest because of certifty process. Due
to the fact that the joint responsibility imposed on the members of the profession stands
somewhere between the tax and the law of obligations, the practice of responsibility
includes many legal gaps that may be against the member of the profession. In order to
clarify this special responsibility situation, the concept of professional care, which is
determined as a criterion for holding the members of the profession jointly and severally
liable by judicial decisions, has been emphasized.
Determining the liability limits of the members of the profession; Code of Obligations No.
6098 of both themselves and the taxpayers. It also affects the right of recourse to each
other and their demands for the exercise of this right. If the conditions are met; It is
possible for the taxpayer to recourse to the sworn-in certified public accountant in internal
relations against the member of the profession who does not fulfill his duty properly and
due to the tax loss, penalty and delay interests that the member of the profession has to pay for various reasons. Since such internal relations are a private law relationship, if there is
an arbitration clause in the contract between the parties, it will be resolved by arbitration,
and if the dispute cannot be concluded, it will be resolved by the judicial organs.
While the judge shares the responsibility in the recourse requests made by the member of
the sworn-in certified public accountant and the taxpayer to each other; In particular, it will
focus on the concept of professional care of the sworn-in certified public accountant,
evaluate all the circumstances and conditions of the incident and the gravity of the fault,
and take into account the roles of those responsible in the event, in accordance with equity
Lipases for targeted industrial applications, focusing on the development of biotechnologically significant aspects: A comprehensive review of recent trends in protein engineering
No full textLipases are remarkable biocatalysts, adept at catalyzing the breakdown of diverse compounds into glycerol, fatty acids, and mono- and di-glycerides via hydrolysis. Beyond this, they facilitate esterification, transesterification, alcoholysis, acidolysis, and more, making them versatile in industrial applications. In industrial processes, lipases that exhibit high stability are favored as they can withstand harsh conditions. However, most native lipases are unable to endure adverse conditions, making them unsuitable for industrial use. Protein engineering proves to be a potent technology in the development of lipases that can function effectively under challenging conditions and fulfill criteria for various industrial processes. This review concentrated on new trends in protein engineering to enhance the diversity of lipase genes and employed in silico methods for predicting and comprehensively analyzing target mutations in lipases. Additionally, key molecular factors associated with industrial characteristics of lipases, including thermostability, solvent tolerance, catalytic activity, and substrate preference have been elucidated. The present review delved into how industrial traits can be enhanced through directed evolution (epPCR, gene shuffling), rational design (FRESCO, ASR), combined engineering strategies (i.e. CAST, ISM, and FRISM) as protein engineering methodologies in contexts of biodiesel production, food processing, and applications of detergent, pharmaceutics, and plastic degradation
Spray drying Eudragit® E-PO with acetaminophen using 2- and 3-fluid nozzles for taste masking
No full textConventional spray drying using a 2-fluid nozzle forms matrix microparticles, where drug is distributed throughout the particle and may not effectively mask taste. In contrast, spray drying using a 3-fluid nozzle has been reported to encapsulate material. The objective of this study was to spray dry Eudragit® E-PO (EE) with acetaminophen (APAP), a water-soluble model drug with a bitter taste, using 2- and 3-fluid nozzles for taste masking. Spray drying EE with APAP, however, resulted in yields of ≤ 13 %, irrespective of nozzle configuration. Yields improved when Eudragit® L 100-55 (EL) or Methocel® E6 (HPMC) was used in the inner fluid stream of the 3-fluid nozzle or in place of EE for the 2-fluid nozzle. Drug release from microparticles prepared with the 2-fluid nozzle was relatively rapid. Using EE in the outer fluid stream of the 3-fluid nozzle resulted in comparatively slower drug release, although drug release was observed, indicating that encapsulation was incomplete. Results from these studies also show that miscible polymers used in the two fluid streams mix during the spray drying process. In addition, findings from this study indicate that the polymer used in the inner fluid stream can impact drug release
Detection of DDOS attack in IoT networks using deep learning technologies
Get PDFThe primary objective of this research was to investigate and develop effective techniques
for detecting Distributed Denial of Service (DDoS) attacks in Internet of Things (IoT)
networks using Convolutional Neural Networks (CNNs). Through theoretical analysis,
empirical evaluations, and practical implementations, we have made significant strides
towards achieving this goal.
Our findings demonstrate that CNN-based approaches hold promise for detecting DDoS
attacks in IoT environments, offering several advantages over traditional methods. By
leveraging the inherent capabilities of deep learning, our proposed framework achieved high
detection accuracy while operating efficiently within the resource-constrained constraints
typical of IoT devices. The framework exhibited robustness against adversarial attacks and
demonstrated adaptability across diverse IoT deployments and attack scenarios.
Furthermore, our research contributes to advancing the understanding of DDoS detection in
IoT networks and provides practical insights for cybersecurity practitioners and researchers.
The proposed guidelines and best practices for deploying CNN-based DDoS detection
systems in operational IoT environments serve as valuable resources for ensuring the
security and resilience of IoT ecosystems against evolving cyber threats. Our research
underscores the potential of deep learning technologies, particularly CNNs, in addressing
the challenges of DDoS detection in IoT networks. By developing robust and scalable
solutions, we have taken significant steps towards enhancing the security posture of IoT
infrastructures and safeguarding against malicious attacks.Bu araştırmanın temel amacı, Evrişimli Sinir Ağlarını (CNN'ler) kullanarak Nesnelerin
İnterneti (IoT) ağlarında Dağıtılmış Hizmet Reddi (DDoS) saldırılarını tespit etmek için
etkili teknikleri araştırmak ve geliştirmekti. Teorik analizler, ampirik değerlendirmeler ve
pratik uygulamalar sayesinde bu hedefe ulaşma yolunda önemli ilerlemeler kaydettik.
Bulgularımız, CNN tabanlı yaklaşımların, IoT ortamlarındaki DDoS saldırılarını tespit etme
konusunda umut vaat ettiğini ve geleneksel yöntemlere göre çeşitli avantajlar sunduğunu
gösteriyor. Derin öğrenmenin doğal yeteneklerinden yararlanarak, önerdiğimiz çerçeve, IoT
cihazlarına özgü kaynak kısıtlı kısıtlamalar dahilinde verimli bir şekilde çalışırken yüksek
algılama doğruluğu elde etti. Çerçeve, rakip saldırılara karşı sağlamlık sergiledi ve çeşitli
IoT dağıtımları ve saldırı senaryolarında uyarlanabilirlik gösterdi.
Ayrıca araştırmamız, IoT ağlarında DDoS algılama anlayışının geliştirilmesine katkıda
bulunuyor ve siber güvenlik uygulayıcıları ve araştırmacıları için pratik bilgiler sağlıyor.
CNN tabanlı DDoS algılama sistemlerinin operasyonel IoT ortamlarında
konuşlandırılmasına yönelik önerilen yönergeler ve en iyi uygulamalar, IoT ekosistemlerinin
gelişen siber tehditlere karşı güvenliğini ve dayanıklılığını sağlamak için değerli kaynaklar
olarak hizmet eder. Araştırmamız, IoT ağlarında DDoS tespitinin zorluklarını ele almada
derin öğrenme teknolojilerinin, özellikle de CNN'lerin potansiyelinin altını çiziyor. Sağlam
ve ölçeklenebilir çözümler geliştirerek, IoT altyapılarının güvenlik duruşunu iyileştirme ve
kötü niyetli saldırılara karşı koruma sağlama yönünde önemli adımlar attık
Exploration Of Key Approaches to Enhance Evacuated Tube Solar Collector Efficiency
No full textThis research is carried out to investigate and examine the critical benefits and significant contributions of integrating nanoparticles into the ETSC system to enhance the thermal efficiency, thermal performance, temperature out, and energy storage of the ETSC. The Simcenter STAR-CCM+ 2022.1 software package implemented numerical analysis and thermal simulations. Further, a comparative analysis is conducted on two case studies to validate the critical role and contributions of employing the aluminum oxide nanomaterial in the solar collector system to enhance its thermal efficiency and improve its thermal performance and heat transfer, including (1) conventional ETSC and (2) ETSC with Al2O3. According to the numerical analysis and comparative study findings, the results of this research revealed that employing and adding the aluminum oxide nanomaterial into the ETSC system had contributed to several beneficial impacts and significant advantages. In addition, using Al2O3 achieved enhancements in the thermal efficiency, increases in the outlet collector’s temperature, improvements in the rate of heat flux of the pipes, the tube inside the collector, heat transfer of the hot water storage tank, and a rise in the temperature gradient the hot water temperature increased from (between 44.3 and 74.8 ºC) to (between 49.6-80.3 ºC). Besides, the velocity of the water flow inside the solar collector in the second case in which the aluminum oxide nanoparticles are used was higher due to the absorption of further solar radiation and thermal energy, which resulted in a considerable increase in the kinetic energy of water molecules from 0.01 to 0.07 m/s. Also, it was found that the velocity directions and profile were slightly more turbulent in the second case than the conventional solar collector due to more thermal energy absorbed and stored in the ETSC from solar radiation. © 2024, Penerbit Akademia Baru. All rights reserved
Efficacy of erythropoietin as a neuroprotective agent in CKD-associated cognitive dysfunction: A literature systematic review
Get PDFPatients with chronic kidney disease (CKD) often experience mild cognitive impairment and other neurocognitive disorders. Studies have shown that erythropoietin (EPO) and its receptor have neuroprotective effects in cell and animal models of nervous system disorders. Recombinant human EPO (rHuEPO), commonly used to treat anemia in CKD patients, could be a neuroprotective agent. In this systematic review, we aimed to assess the published studies investigating the cognitive benefits of rHuEPO treatment in individuals with reduced kidney function. We comprehensively searched Pubmed, Cochrane Library, Scopus, and Web of Science databases from 1990 to 2023. After selection, 24 studies were analyzed, considering study design, sample size, participant characteristics, intervention, and main findings. The collective results of these studies in CKD patients indicated that rHuEPO enhances brain function, improves performance on neuropsychological tests, and positively affects electroencephalography measurements. These findings suggest that rHuEPO could be a promising neuroprotective agent for managing CKD-related cognitive impairment
Sustainable Prosthetic Socket Design: A Study of Eco-Composites and Natural Fibers for Transtibial Amputees
No full text2nd International Conference on Engineering and Science to Achieve the Sustainable Development Goals, ICASDG 2023 -- 9 July 2023 through 10 July 2023 -- Hybrid, Tabriz -- 197984This paper examines the use of eco-composites for manufacturing prosthetic sockets, especially those reinforced by natural fibers. The composites under investigation are hybrid, with a matrix of laminating polyurethane resin (in an 80:20 ratio) combined with bamboo and kenaf natural fibers, as well as carbon fiber and perlon synthetic fibers. The mechanical properties of the eco-composites are studied with a focus on the impact of different fiber types. The composite materials were constructed in three groups, each consisting of ten layers. The first group had four perlon, two carbon fiber, and four perlon layers; the second group had two layers each of perlon, kenaf, carbon fiber, and perlon; and the third group had two perlon layers, as well as two layers each of bamboo fiber, carbon fiber, and perlon. In addition, the research included the utilization of sensors placed on four areas of the residual limb (anterior, posterior, lateral, and medial) to gauge the interface pressure between the socket and the limb. A 26-year-old male patient who had undergone a right leg amputation participated in the study. Three different levels of interface pressure were measured and become input to ANSYS 14.5 software to evaluate the stresses, deformation, and safety factors during movement. The study found that the third group exhibited the best yield stress, ultimate stress, elasticity modules, and fatigue compared to the other two groups. Additionally, the patient's gait cycle while using a conventional prosthetic and the composite prosthetic socket was analyzed using a force plate. The study found no significant difference in parameters between the two cases. However, the use of the composite prosthetic socket resulted in less obvious and more acceptable differences between the left and right limbs. © 2024 American Institute of Physics Inc.. All rights reserved