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σ-Hole, lone-pair-hole, and π-hole site-based interactions in aerogen-comprising complexes: a comparative study
No full textHerein, the potential of ZO3 and ZF2 aerogen-comprising molecules (where Z = Ar, Kr, and Xe) to engage in σ-, lp-, and π-hole site-based interactions was comparatively studied using various ab initio computations. For the first time, a premier in-depth elucidation of the external electric field (EEF) influence on the strength of the σ-, lp-, and π-hole site-based interactions within the ZO3/ZF2⋯NH3 and ⋯NCH complexes was addressed using oriented EEF with disparate magnitude. Upon the energetic features, σ-hole site-based interactions were noticed with the most prominent preferability in comparison to lp- and π-hole analogs. This finding was ensured by the negative interaction energy values of −11.65, −3.50, and −2.74 kcal mol−1 in the case of σ-, lp-, and π-hole site-based interactions within the XeO3⋯ and XeF2⋯NH3 complexes, respectively. Detailedly, the strength of the σ- and lp-hole site-based interactions directly correlated with the atomic size of the aerogen atoms and the magnitude of the positively oriented EEF. Unexpectedly, an irregular correlation was noticed for the interaction energies of the π-hole site-based interactions with the size of the π-hole. Interestingly, the π-hole site-based interactions within Kr-comprising complexes exhibited higher negative interaction energies than the Ar- and Xe-comprising counterparts. Notwithstanding, a direct proportion between the interaction energies of the π-hole site-based interactions and π-hole size was obtained by employing EEF along the positive orientation with high strength. The present outcomes would be a fundamental basis for forthcoming progress in studying the σ-, lp-, and π-hole site-based interactions within aerogen-comprising complexes and their pertinent applications in materials science and crystal engineering
Anti-hepatocellular carcinoma activities of novel hydrazone derivatives via downregulation of interleukin-6
No full textHepatocellular carcinoma (HCC) is one of the leading causes of cancer-related morbidity worldwide. Sorafenib is a first-line drug for the treatment of HCC, however, it is reported to cause serious adverse effects and may lead to resistance in many patients. In this study, 20 hydrazone derivatives incorporating triazoles, pyrazolone, pyrrole, pyrrolidine, imidazoline, quinazoline, and oxadiazine moieties were designed, synthesized, and characterized. In addition to molecular docking and in silico ADME study, the cytotoxic activity of the synthesized compounds was evaluated against the human hepatocellular cancer cell line (HepG2) and liver mesenchymal stem cells as a normal cell line. The antitumor activities of the derivatives against sorafenib were compared. Of the 20 synthesized compounds, compound 16 demonstrated potential as a potent anti-HCC drug candidate through downregulation of interleukin 6 which reduces inflammation and tumorigenesis with a strong binding interaction and bioavailability
Innovative microwave-assisted biosynthesis of copper oxide nanoparticles loaded with platinum(ii) based complex for halting colon cancer: cellular, molecular, and computational investigations
Get PDFIn the current study, we biosynthesized copper oxide NPs (CuO NPs) utilizing the essential oils extracted from Boswellia carterii oleogum resin, which served as a bioreductant and capping agent with the help of microwave energy. Afterwards, the platinum(ii) based anticancer drug, carboplatin (Cr), was loaded onto the CuO NPs, exploiting the electrostatic interactions forming Cr@CuO NPs. The produced biogenic NPs were then characterized using zeta potential (ZP), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction spectroscopy (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques. In addition, the entrapment efficiency and release profile of the loaded Cr were evaluated. Thereafter, SRB assay was performed, where Cr@CuO NPs demonstrated the highest cytotoxic activity against human colon cancer cells (HCT-116) with an IC50 of 5.17 μg mL−1, which was about 1.6 and 2.2 folds more than that of Cr and CuO NPs. Moreover, the greenly synthesized nanoparticles (Cr@CuO NPs) displayed a satisfactory selectivity index (SI = 6.82), which was far better than the free Cr treatment (SI = 2.23). Regarding the apoptosis assay, the advent of Cr@CuO NPs resulted in an immense increase in the cellular population percentage of HCT-116 cells undergoing both early (16.02%) and late apoptosis (35.66%), significantly surpassing free Cr and CuO NPs. A study of HCT-116 cell cycle kinetics revealed the powerful ability of Cr@CuO NPs to trap cells in the Sub-G1 and G2 phases and impede the G2/M transition. RT-qPCR was utilized for molecular investigations of the pro-apoptotic (Bax and p53) and antiapoptotic genes (Bcl-2). The novel Cr@CuO NPs treatment rose above single Cr or CuO NPs therapy in stimulating the p53-Bax mediated mitochondrial apoptosis. The cellular and molecular biology investigations presented substantial proof of the potentiated anticancer activity of Cr@CuO NPs and the extra benefits that could be obtained from their use
High inflation during Russia–Ukraine war and financial market interaction: Evidence from C-Vine Copula and SETAR models
No full textThis paper examines the interaction between three financial markets: energy and non-energy commodities, bonds and equities, in a particular context of high inflation worldwide, that of Russia–Ukraine war. Our data cover the period January 2016-October 2022. Using a SETAR-GARCH C-Vine Copula model, we provide evidence of two inflation breakouts within COVID pandemic and shortly before Russia–Ukraine war, for all assets considered, and particularly for US 10-Year bond, as an inflation-indexed asset. Over the Russia–Ukraine war period, both linear and nonlinear models explain the studied assets’ behavior faced with high inflation. C-Vine Copula analysis shows that oil prices (WTI), as an inflation-producing assets, impact the volatility of financial markets (VIX) in times of war. This analysis indicates also that the NASDAQ index, as an inflation-exposed assets, is sensitive to commodities and energy prices that drive inflation. Furthermore, we find a high positive Kendall\u27s tau for all combinations between US 10-Year and all other assets. These results provide strong evidence of the association between US 10-Year futures, as a vehicle of inflation, and all studied assets. Lastly, our findings confirm the evidence that Russia–Ukraine war generated two significant shocks, Gas (NG) prices and financial markets’ volatility (VIX). This study is of crucial interest to policy and decision makers to the extent that it provides a framework for understanding, in a context of high inflation, the mechanisms linked to the vehicles for transmitting this inflation, its pricing process, and its impact on the equity market
Zone In Not Out! The Key to Winning High-Level Tetris
No full textAutomating a perceptual-motor task will not win you a perceptual-motor contest. Despite claims that mindless automaticity is the essence of expertise, the view espoused here is that automaticity is worthwhile only because it enables the expert to plan and strategize. Indeed, the purpose of learning to manually shift gears is to eventually ignore that function to focus instead on actual driving. To perform well, the expert must transition their attention from a task’s low-level components to its high-level nuances. This is best understood in real-world scenarios (e.g. driving, in which performance is dynamic and sometimes competitive). This argument is based on a years-long, longitudinal case study of learning to play the puzzle game, Tetris. Tetris is intensively perceptual-motor with complicated manual routines needed to manage expert game speeds. For this case study, the player began as an advanced novice but successfully transitioned to championship level in the 2020 Classic Tetris World Championship. Initially, the challenge was gaining enough skill to make and execute perceptual-motor decisions in a fraction of a second. However, once that process became automatic, the player could spend those freed mental resources elsewhere. Performance was better for all games when the player was mentally engaged and used their focused attention to plan ahead rather than just automatically respond to the game pieces. We argue that the end goal for automating perceptual-motor skills in competitive, dynamic environments is to free cognitive space in the brain for the user to excel strategically
Feasibility of Oil Palm Agroforestry System: Evaluating the Application of Oil Palm Ash for Enhancing Cherry Tomato (Solanum Lycopersicum. Var. Nancy Rz) Production Using Brackish Water.
Get PDFMonoculture systems of oil palm production are ravaging the world’s tropical forests, causing deforestation and biodiversity loss, which contribute to climate change at an uncontrollable pace. Oil palm agroforestry systems (AFSs), one of the strategies of regenerative agriculture, have proven to reverse the unfavorable effects of the oil palm monoculture systems. A sustainable means of soil fertilization and irrigation must be explored to improve the feasibility of oil palm AFSs. This study evaluates the impact of the application of oil palm ash and brackish irrigation on cherry tomato production. The experiment was conducted in a hydroponic system using a 2*4 factorial experimental design to investigate the impact of the application of four fertilizer treatments namely T1: oil palm ash; T2: plant-based compost; T3: oil palm ash and plant-based compost (1:1); and T4: no fertilizer treatment, only irrigated with A&B Nutrient Solution (NS) as the control treatment and two water salinity levels of fresh and brackish water on cherry tomato fruit yield, cherry tomato fruit nutrient concentration levels and the total organic matter (TOM) and total organic carbon (TOC) of the soil used in this study for the cultivation of cherry tomatoes. For freshwater, T3 recorded an average fruit yield of 33.016 tons/ha compared to the average yield of the control treatment of 35.775 tons/ha with no significant difference between them. For brackish water, compared to the average fruit yield of the control treatment of 27.802 tons/ha, T3 noted an average fruit yield of 27.330 tons/ha with no significant difference. In the cherry tomato samples that were irrigated with fresh water, the ones from T3 were higher than the control treatment in K, Ca, Zn, Mg, and Na while with brackish water, T3’s cherry tomato samples were higher in N, K, Ca, Fe, Mn, Zn, Cu, Mg and Na when compared to the control treatment. In T1, the soil that was irrigated with freshwater exhibited the only increase of about 25.57% in TOM and TOC with a p-value of 0.000 whereas the soil that was irrigated with brackish water displayed the least reduction of about 17.41% with a p-value of 0.000. Both the TOM and TOC significantly decreased in the soil samples that were irrigated with water from both salinity levels in T2, T3, and the control treatment. Subsequent studies should be conducted to determine the appropriate application rate of oil palm ash for cherry tomatoes in diverse water salinity levels, evaluate the application of oil palm ash on other crops irrigated with higher water salinity levels, investigate the impact of the combination of oil palm ash and plant-based compost on other crops in brackish water irrigation. Our findings suggest that the use of oil palm ash and brackish water is a sustainable means of soil fertilization and irrigation, that will enable oil farmers to transition oil palm monoculture to oil palm AFSs
Egypt’s Legal Modernism: Challenging the National Discourse
Get PDFEgypt’s legal modernity is the story of the modern Egyptian state itself. Reforming the country’s judiciary in the late nineteenth century was meant to achieve ambitious aims beyond the functionality of a justice system. The utmost goal was the country’s independence from the suzerainty of the Ottoman Empire. The judicial reforms modernized the Egyptian state and built a judiciary and legal community like no other place. Egypt achieved its independent judiciary before gaining its political independence. That was a remarkable achievement of the judicial reform. That rich part of Egypt’s modern history is negated and disregarded from public awareness. Not even law students in Egypt study their modern legal history, which spans 150 years! The oblivion and distortion of Egypt’s collective conscience have resulted from the post-1952 rhetoric following the abolishment of the monarchy and, more substantially, the Islamization of the country since then. This paper challenges the national discourse regarding the tale of Egypt’s legal modernism and investigates the effect of the identity crisis that has plagued post-colonial Egypt
The Uses and Gratifications of Social Audio-Focused Apps: A Case Study of the Clubhouse Application
No full textSocial audio has recently emerged recently as a new form of social media based on voice. It spread rapidly through the Clubhouse application, which became a significant trend during the COVID-19 pandemic. The study aims to explore Egyptian content creators\u27 motivations to join Clubhouse, study their motivations to produce their content, and identify the gratifications obtained from using this application. It also seeks to investigate the application`s sustainability within the Egyptian context by outlining the challenges faced by the Egyptian content creators. The study employs the uses and gratifications theory, conducting in-depth interviews with 17 Egyptian content creators. The findings reveal that the motivations of Egyptian content creators to join the Clubhouse application are to socialize with other people, particularly during COVID-19, and to satisfy their curiosity. Social responsibility, encouragement from friends, and managing discussions according to their own rules emerged as the key motivations for content creators to produce their content. The gratifications obtained include networking/building connections, self-development, personal branding, opening opportunities, freedom of expression, and keeping up with current affairs. Furthermore, the gratifications related to the technical features are audio superiority, convenience utility, easy usability, good audio quality, and documentation. The challenges identified include theft and fake profiles, cyberbullying, addiction, and ineffective moderation. Additionally, the recent update leads to limited accessibility and reach, and less privacy. The findings revealed that the application\u27s sustainability within the context of Egypt is conditioned by addressing these challenges in addition to ensuring freedom of expression, and establishing a self-sustaining business
Metakaolin-based Geopolymer Concrete; Synthesis, Development and Characterization
Get PDFGeopolymers are rendered as an essential sustainable replacement to the widely used Ordinary Portland Cement (OPC) which causes immense carbon dioxide emissions, hence a detrimental impact on society’s health and the environment. Geopolymers are three-dimensional networks of polymerized tetrahedral silicate and aluminate in the form of Q4(4Al), Q4(3Al) and Q4(2Al) which act as the principal binding phase in concrete. Past research has reported the synthesis of geopolymers from different aluminosilicates precursors, their characterization, and their wide range properties. However, previous studies still have not properly investigated effective range of synthesis ratios for a particular source material, optimum curing regimes, short- and long-term properties of paste, mortar and concrete, and finally possible construction applications. This research has focused on the study of kaolin calcination for proper geopolymerization of metakaolin using sodium hydroxide and sodium silicate, development of a guidance design chart that shows range of feasible mixes and the design of geopolymer concrete and the study of its mechanical properties. The design chart is the main contribution of this research and aims at providing a well-established baseline for the synthesis of metakaolin geopolymer.
In the first stage, the used kaolin was properly characterized before and after calcination using different spectroscopic techniques including XRD, TGA, FTIR and 27Al and 29Si solid state MAS NMR. It was found that calcination at 750°C for 7 hours results in effective breakage of the hydroxyl group from the kaolin sheets. In the second stage, geopolymer paste was produced at different mixing percentages. A total of 52 mixes were designed and studied. Based on the quantitative analysis of compressive strength and qualitative analysis of setting time and workability, the feasible range for producing a workable geopolymer mix of reasonable strength was highlighted. The 28-day compressive strength of geopolymer paste ranged between 30 to 94 MPa and the workability varied from being very stiff to highly workable depending on the synthesis ratios. The research points out a concern, which was not previously addressed in the literature, the high temperature of geopolymer paste at some synthesis percentages. This requires further investigation for practical handling of the material in construction applications. The stress-strain curves of geopolymer paste showed a brittle behavior and the lowest and highest tangent modulus of elasticity at 7-day was recorded to be 4.4 and 7.3 GPa respectively. 29Si and 27Al MAS NMR analysis detected the presence of tetrahedrally coordinated silicate and aluminate crosslinked in form of Q4(4Al) and Q4(3Al) and thus confirmed the formation of geopolymer gel network. Finally, six geopolymer concrete mixes were developed at specific mixing ratios depending on the developed guidance chart and their mechanical properties were investigated. The studied fresh and mechanical properties include workability, temperature, compressive strength, flexural strength, drying shrinkage, rapid chloride penetration test in addition to chemical resistance in acid (10% hydrochloric acid) and sulfates (saturated magnesium sulfate solution) for a total duration of 4 months.
It was concluded that calcined kaolin can be alkaline activated to produce geopolymer concrete of comparable or even advanced mechanical properties at ambient curing temperature. Calcination of kaolin is a primary step that needs to be effectively conducted at the right temperature, duration and rate prior to geopolymerization. The crosslinking of silicate and aluminate species to form geopolymer network depends on the synthesis materials percentages. Research conducted contributed to demonstrating the feasible range of metakaolin, sodium silicate and sodium hydroxide to synthesize geopolymer and clarifying the relationship between the percentages of three component system and the compressive strength development as a first step towards reaching a structure-directed synthesis. Geopolymer concrete exhibited superior mechanical properties and can be used in various construction applications based on the obtained properties
Improving the Energy Efficiency of Residential Buildings in Egypt through Whole Building Simulations
Get PDFResidential buildings consume around 40% of total electricity consumption in Egypt. This research investigates the energy saving potential of the Green Pyramid Rating system (GPRS) and Tarsheed rating system on the building envelopes of mid-rise middle income residential buildings in Cairo through energy modelling and simulation. The study evaluates the economic feasibility of the recommendations of the two rating systems through Life Cycle Cost (LCC), Simple Payback Period (SPP), Discounted Payback Period (DPP), Net Present Value (NPV), and Internal Rate of Return (IRR) Calculations. This research also aims to develop energy efficiency recommendations to achieve 30% energy savings above the national baseline. The results of this study indicate that the recommendations of GPRS for building envelopes can save up to 25% of total annual energy consumptions at a SPP of 12 years while the recommendations of Tarsheed can save up to 27% of total annual energy consumptions at a SPP of 21 years. Furthermore, this study suggests that up to 30% savings in total annual energy consumption could be achieved through improving the energy efficiency of the building envelope at a SPP of 9 years. However, the proposed energy efficiency measures are mostly not feasible at current interest rates in Egypt. Therefore, more favorable interest rates of 10% or less should be available for energy efficiency investments in buildings to promote their adoption