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Turkey and Germany in the interregnum: new foreign policy strategies for a multipolar world
No full textThere is an emerging consensus that the existing international system is deteriorating. The world is no longer unipolar, and multipolarity seems to be the next system in line. Within this context, regional powers have experienced shifts in their foreign policies, including Turkey and Germany. This article seeks to not only offer a comparative conceptualisation of how these shifts affect Turkey’s and Germany’s foreign policies but also how they influence the Turkey-Germany-EU triangle. It first conceptualises the decline of the post-war liberal international order and the emergence of a new order to better locate Turkey’s and Germany’s place in it. It then identifies parallel and differing patterns in Turkey’s and Germany’s foreign policies that have emerged in response to the decaying international order. Turkey’s relative independence as a non-EU member and Germany’s relative leadership constraint as the ‘hegemon’ of the EU have set forth their foreign policy paths–thus also defining their priorities of regime security versus multilateralism, respectively. At the same time, both have adopted transactionalism as a central point of their foreign policy strategies. The article concludes with recommendations to increase bilateral cooperation between Turkey and Germany as well as Turkey and the EU in the coming order
A comparative analysis of lightweight, high-performance flax fiber and upcycled graphene reinforced polypropylene sustainable composites for automotive industry
No full textThe automotive industry's pursuit of lightweight, high-performance, and sustainable materials has driven interest in natural fiber-reinforced thermoplastics. However, challenges such as moisture sensitivity, lower strength, and fiber-matrix compatibility hinder their widespread adoption. To address these constraints, this study developed sustainable compound formulations incorporating recycled waste components and natural fibers as alternatives to injection-molded composites reinforced with long glass fibers (LGF) for structural applications in the automotive industry. The newly developed compound comprised PP reinforced by 40 wt% alkaline treated flax fiber (FF), 1 wt% waste tire-derived graphene nanoplatelets (GNP), and 3 wt% compatibilizer, resulting in significant improvements in flexural modulus and strength, surpassing both neat homopolymer PP (homoPP) and recycled PP (rePP) by 202% and 92.5%, and 161.5% and 54.7%, respectively. To assess their viability, mechanical, thermal, and rheological properties were compared with commercial counterparts used in serial production. Furthermore, a comparative life cycle assessment evaluated the carbon footprint of different matrix types, revealing that the rePP-based formulation reduced CO2 emissions by 50% compared to LGF/homoPP while achieving a 7.2% weight reduction. This study successfully demonstrates the potential of integrating natural fibers and waste-derived reinforcements into PP composites, offering a lightweight, high-performance, and environmentally friendly alternative for automotive applications. Highlights: Sustainable PP composites developed as alternatives to glass fiber materials Flax fibers and upcycled GNP utilized for lightweight composite fabrication Flexural modulus and strength significantly improved in PP composites. Life Cycle Assessment performed for developed and commercial composites 50% CO2 emission reduction achieved using recycled PP as a matrix in composites
A variational Bayesian marginalized particle filter for jump Markov nonlinear systems with unknown measurement noise parameters
No full textThis paper studies a new variational Bayesian marginalized particle filter for estimating the state vector of a jump Markov nonlinear system (JMNLS) with unknown measurement noise parameters. Conjugate priors are assigned to the variables indicating the system mode of the JMNLS and the measurement noise parameters, which are regarded as unknown parameters. According to the marginalized particle filter, the unknown parameters are marginalized from the joint posterior distribution of the state and the unknown parameters of the JMNLS. The posterior distribution of the state is then approximated by using an appropriate particle filter, and the posterior distributions of the system mode and the measurement noise parameters conditionally on each state particle are calculated by using variational Bayesian inference. A simulation study is conducted to compare the proposed method with state-of-the-art approaches in the context of a modified nonlinear benchmark model and radar target tracking
New insights of cerium oxide nanoparticles in head and neck cancer treatment
No full textHead and neck cancer (HNC) is a genetically complex cancer type having treatment difficulties due to affecting multiple organs in complex anatomical sites. Radiotherapy resistance, chemotoxicity, post-surgery disability makes HNC treatment more complicated. Therefore, there is need to developed new treatment approaches. Nanoparticle-based therapies especially cerium oxide nanoparticles with its anti-cancer features, high catalytic activity, anti- or pro-oxidant and radio-protective properties give a boon for HNC treatment. In the current study, two dextran-coated cerium oxide nanoparticles (Dex-CeNPs) namely SD1 and SD2 were synthesized and characterized by using two types of dextran (D1 and D2) having distinct molecular weights and branching characteristics to understand their potential as a new HNC treatment strategy while evaluating the role of dextran type. The effectivity of the SD1 and SD2 on the HNC cell lines (A253, SCC-25, FaDu) were investigated by analyzing their cytotoxicity, genotoxicity, reactive oxygen species (ROS) generation properties. Low IC50 value, high ROS generation and stability profiling of SD2 compared to SD1 indicates the distinct function of dextran type on Dex-CeNPs effectivity on HNC. To better elucidate the effectivity of SD2, flow cytometry analysis and pro-apoptotic (TP53, CASP3, BAX) and anti-apoptotic (Bcl-2) gene expression profiling were investigated in detail. The findings indicate that SD2 exhibits an influence on head and neck cancer cells via the apoptotic pathway. Our research sets the framework for the development of Dex-CeNPs as remarkable nanotherapeutic candidates for treatment of head and neck cancer
Optimal taxation of capital in the presence of declining labor share
No full textWe analyze the implications of the decline in labor's share in national income for optimal Ramsey taxation. It is optimal to accompany the decline in labor share by raising capital taxes only if the labor share is falling because of a decline in competition or other mechanisms that raise the share of pure profits. This result holds under various alternative institutional arrangements that are relevant for optimal taxation of capital income. A quantitative application to the US economy shows that soaring profit shares since the 1980s can justify a significantly increasing path of capital income taxes
Nutrient limitations on photosynthesis: from individual to combinational stresses
No full textLiebig's law of the minimum states that increasing photosynthetic productivity on nutrient-impoverished soils depends on addressing the most limiting nutrient. Research has identified the roles of different mineral nutrients in photosynthetic processes. However, diffusional and biochemical regulation of photosynthesis both feature patterns of cumulative effects that jointly determine photosynthetic capacity. More importantly, responses to multiple nutrient stresses are not simply additive and require a comprehensive understanding of how these stresses interact and impact photosynthetic performance. In this review we highlight key macroelements for photosynthesis – nitrogen, phosphorus, potassium, and magnesium – focusing on their unique functions and interactions in regulating carbon fixation under multiple nutrient deficiencies, with the goal of enhancing crop productivity through balanced nutrient applications
Nanobiosurfactants: molecules of the 21st century in pharmacy and cosmetics
No full textBiosurfactants are a diverse group of molecules with unique surface-active properties that are synthesized by various microorganisms such as bacteria, yeast, and fungi. These molecules have gained a lot of attention due to their remarkable characteristics, such as low toxicity, high biodegradability, and excellent economic sustainability. In addition to their surface-active properties, biosurfactants have been found to exhibit antimicrobial, and antitumor activities. Nanobiosurfactants, the new microbes-derived compounds issued from nanobiotechnology and including a large variety of nanoparticles (NPs), are currently acknowledged as the molecules of the century. Nanobiosurfactants may refer to either microbes- or biosurfactant-mediated metal NPs as well as other organic and inorganic NPs such as microbial nano-emulsions and microbial extracellular vesicles. Based on the nature of their biosurfactants they can be classified according to their chemical composition, molecular weight, ionic charge and secretion type. Nanobiosurfactants are offering new perspectives of applications specifically in medical and cosmetic industries, considering their low toxicity, specific functionalization, and biocompatibility. They have shown promising results in targeted drug delivery, cancer therapy and health care products. Nevertheless, nanobiosurfactant industries are still showing some limits related mainly to low yields, difficulties in standardization, purification and characterization that put in question their economic efficiency and biological safety
Synthesis of bovine serum albumin-coated magnetic single-walled carbon nanotubes as a delivery system for mitoxantrone
No full textIn this study, a bovine serum albumin (BSA)-coated magnetic single-walled carbon nanotube (mCNT) was synthesized using covalent functionalization. Mitoxantrone (MTO) was chosen as a model drug, and loading/release profiles of mCNTs were evaluated. To synthesize BSA-coated mCNT, 1-ethyl-3-(3-(dimethylamino)propyl) carbodiimide and N-hydroxysuccinimide were used as cross-linking agents. The success of the functionalization process was demonstrated through various analysis techniques such as Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, vibrating sample magnetometer, and scanning electron microscopy. The saturation magnetization of mCNT-BSA was 15.6 emu/g, indicating its potential for magnetically targeted drug delivery systems. Finally, MTO was physically loaded on the BSA-coated mCNT (mCNT-BSA) and the results were compared to those of mCNT. mCNT-BSA showed less drug loading capacity but more release response than mCNT. Considering drug release and cytotoxicity test results, MTO-loaded mCNT-BSA nanoparticles have great potential for cancer treatment
Nonwoven surface treatments for disposable hygiene products
No full textBaby diapers, adult incontinence products, feminine hygiene items, and wet wipes are extensively utilized nonwoven products. The properties of nonwovens are significantly influenced by surface treatments. These treatments impart hydrophilicity, hydrophobicity, skincare benefits, adhesion reduction, odor control, enzymatic inhibition, pH control, probiotics, prebiotics, controlled release of active agents, and antimicrobial activity, all of which enhance the performance and user experience of these products. This study reviews surface treatments for nonwoven disposable hygiene products, focusing on their types, effects, performance, and safety considerations. Most research focuses on hydrophilicity and hydrophobicity due to the absorbent nature of these articles. Small molecule applications are prominent, though polymer-based formulations offer greater versatility. Smart materials, nanofibers, and nanoparticles are becoming increasingly popular in the field. Concerns regarding sustainability, biodegradability, biocompatibility, product safety, and compliance with emerging environmental regulations are increasing. Focusing on these areas will drive the development of next-generation disposable hygiene products that meet changing regulations, consumer demands and concerns. Highlights: Innovative agents improve user comfort and hygiene in surface treatments. Small molecule treatments are common although polymers provide more versatility. Smart coatings and nanomaterials offer advanced surface treatments. Biodegradable treatments lead the shift towards sustainable hygiene products. Consumer preferences shape the next generation of hygiene articles
Biomedical applications of metal-organic frameworks revisited
No full textMetal-organic frameworks (MOFs) have been shown to be great alternatives to traditional porous materials in various chemical applications, and they have been very widely studied for biomedical applications in the past decade specifically for drug storage. After our review published in 2011 [Keskin and Kızılel, Ind. Eng. Chem. Res. 2011, 50 (4), 1799-1812, 10.1021/ie101312k], we have witnessed a very fast growth not only in the number and variety of MOFs but also in their usage across a broad spectrum of biomedical fields. With the recent integration of molecular modeling and data science approaches to the experimental studies, biomedical applications of MOFs have been significantly accelerated positioning them as pivotal components in the regenerative medicine, medical imaging, and diagnostics. In this review, we visited the diverse biomedical applications of MOFs considering the recent experimental and computational efforts on drug storage and delivery, bioimaging, and biosensing. We focused on the underlying mechanisms governing the molecular interactions between MOFs and biological systems and discussed both the opportunities and challenges in the field to highlight the potential of MOFs in advanced therapeutics for cancer and neurological diseases