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Towards a functional place: Syrian refugees' contending with the European Union's host-home schism
No full textThe refugee crisis is rooted in the host-home schism, a fundamental disconnection between the host (the EU) and home (refugees' country of origin). This schism is generated by the EU's migratory policies resulting from the struggles between different political camps, and the resulting compromise between the far-right/exclusive camp and the liberal camp. To assess this schism, we have conducted an in-depth analysis of Syrian refugees' perceptions with focus groups. Our findings demonstrate that this schism between home and host countries shapes the everyday experiences of the Syrian refugees in the EU. The divide between home and host countries is reflected in their experiences, limiting their agency and distorting their identity. As a result, this schism renders their integration into European countries ineffective. Moreover, it creates multiple dilemmas for their positions in their host societies as they find themselves entrapped inside multifaceted contradictions that they cannot escape from whatever they do. We propose that the host-home schism could be bridged by institutionalizing both refugees' transnational activities and responsibility towards home. We label this proposal as a functional place
Feasibility and performance evaluation of randomly oriented strand recycled composite skins in sandwich structures: a green cost-effective solution for aerospace secondary load-bearing applications
No full textDespite the advantages of recycled randomly oriented strand (ROS) composites over recycled grinded ones, the warpage issue hinders their adaptation in the industry due to tolerance requirements. To address this challenge, ROS composites are incorporated into secondary bonded sandwich structures such that the core material ensures the straightness of the ROS composite skins. Additionally, atmospheric plasma activation (APA) is utilized to enhance the skin/core bonding to prevent skin separation under loading. The ROS composite skins are manufactured via vacuum-assisted hot press to achieve a cost-effective aerospace-grade quality. The structural integrity of the sandwich structure is assessed through flatwise tensile and edgewise compression tests, while the mechanical and thermomechanical performance is evaluated using flexural, impact, and dynamic mechanical analysis (DMA) tests. The flatwise tensile and edgewise compression tests confirm that APA effectively prevents core detachment, as evidenced by an average tensile strength of 2.28 MPa and an average compressive strength of 171.7 MPa. Moreover, the flexural and impact tests show that no premature skin failure occurs, supported by an average facing strength of 59.23 MPa in flexural testing and an average impact energy of 49.96 kJ/m(2). The DMA test indicates that most of the stiffness loss is due to the core material. This comprehensive analysis highlights recycled ROS composites as a sustainable and cost-effective alternative for quasi-isotropic skins in aerospace secondary load-bearing sandwich structures such as floors, doors, engine cowls, and spoilers
Spike and slab regression for nonstationary Gaussian linear mixed effects modeling of rapid disease progression
No full textSelect measures of social and environmental determinants of health (referred to as “geomarkers”), predict rapid lung function decline in cystic fibrosis (CF), defined as a prolonged decline relative to patient and/or center-level norms. The extent to which hyper-localization, defined as increasing the spatiotemporal precision of geomarkers, aids in prediction of rapid lung decline remains unclear. Linear mixed effects (LME) models with specialized covariance functions have been used for predicting rapid lung function decline, but there are few options to properly incorporate spatial correlation into the covariance functions while inducing simultaneous variable selection. Our innovative Bayesian model uses a spike and slab prior for simultaneous variable selection and offers additional advantages when coupled with nonstationary Gaussian LME modeling. This model also incorporates spatial correlation through an additional random effect term that accounts for spatial correlation based on ZIP code distances. We validated the model with simulations and applied it to real CF data from a Midwestern CF Center. We demonstrate how a combination of demographic, clinical, and geomarker variables can be selected as optimal predictors using Bayesian false discovery rate controlling rule. Our results indicate that incorporating spatiotemporal effects and geomarkers into this novel Bayesian stochastic LME model enhances the dynamic prediction of rapid CF disease progression
Electrochemical synthesis and characterization of titanium oxide thin films on covalent polyphenylene-modified gold electrodes as electrode materials for supercapacitor applications
No full textTitanium dioxide (TiO2) is one of the technologically conspicuous materials with a wide range of applications including photocatalysts, waste water treatment and energy storage devices. Here, we report a facile method for the synthesis of TiO2 for supercapacitors. Titanium oxide film was prepared by electrochemical reduction of TiCl4 in oxygen-saturated non-aqueous acetonitrile solution containing tetrabutylammonium perchlorate (TBAClO4), and the cathodic deposition process of metal oxide film on modified and bare gold electrodes was estimated by detailed voltammetric analysis. The modified gold electrodes were achieved by formation of polyphenyl (PPh) organic film on gold via electrochemical reduction of benzene diazonium salt. The resulting Au/PPh/TiOx electrode was subjected to thermal annealing at 400 °C, and then the capacitive performance of Au/PPh/TiO2-400 electrode was evaluated by using electrochemical techniques. Compared to the obtained Au/PPh, Au/TiOx and Au/PPh/TiOx electrodes, Au/PPh/TiO2-400 electrode showed a high specific capacitance of 438.7 F/g at a current density of 0.5 A/g and good stability with a capacitance retention of 95 % after 2500 cycles. Moreover, the assembled asymmetric Au/PPh/TiO2-400//RGO:CB/Au device delivered a maximum energy density of 16.4 Wh kg−1 at a power density of 499.9 W kg−1
Colloidal quantum dots as solution-based nanomaterials for infrared technologies
No full textThis review focuses on recent progress of wet-chemistry-based synthesis methods for infrared (IR) colloidal quantum dots (CQD), semiconductor nanocrystals with a narrow energy bandgap that absorbs and/or emits IR photos covering from 0.7 to 25 micrometers. The sections of the review are colloidal synthesis, precursor reactivity, cation exchange, doping and de-doping, surface passivation and ligand exchange, intraband transitions, quenching and purification, and future directions. The colloidal synthesis section is organized based on precursors employed: toxic substances as mercury- and lead-based metals and non-toxic substances as indium- and silver-based metal precursors. CQDs are prepared by wet-chemical methods that offer advantages such as precise spectral tunability by adjusting particle size or particle composition, easy fabrication and integration of solution-based CQDs (as inks) with complementary metal-oxide-semiconductors, reduced cost of material manufacturing, and good performances of IR CQD-made optoelectronic devices for non-military applications. These advantages may allow facile and materials' cost-reduced device fabrications that make CQD based IR technologies accessible compared to optoelectronic devices utilizing epitaxially grown semiconductors. However, precursor libraries should be advanced to improve colloidal IR quantum dot synthesis, enabling CQD based IR technologies available to consumer electronics. As the attention of academia and industry to CQDs continue to proliferate, the progress of precursor chemistry for IR CQDs could be rapid
Ternary metal-organic framework composite with nanocellulose and deep eutectic solvent for the adsorptive removal of 3-MCPD esters
No full textRemoval of 3-monochloropropane-1,2-diol esters (3-MCPDEs) from edible oils is essential for better quality food consumption due to its detrimental effects on human health. Herein, we present a simple strategy for the in situ growth of a ternary metal–organic framework (Fe–Mn–MOF/N4) with nanocellulose (NC) extracted from almond shells using sulfuric acid (ASS) as a support for 3-MCPD adsorption in spiked extra virgin olive (EVO) oil. The sugar-based deep eutectic solvent (SDES) was also employed as co-solvent to enhance the active sites of the synthesized MOF, thereby increasing the adsorption capacity of the primary solid adsorbents, such as MOF and NC-ASS. The Fe–Mn–MOF/N4 achieved 85% removal of 3-MCPD under optimal conditions (6 h, 40 °C, 60 mg dose of Fe–Mn-MOF/N4, 1 g of NC-ASS, and 200 µL of SDES) via an indirect method. The adsorption performance, analyzed using Langmuir and Freundlich isotherm models, showed excellent adsorption capacity while maintaining the quality of EVO oil within acceptable limits after treatment. Importantly, Fe–Mn–MOF/N4 could be reused up to five times, with an adsorption efficiency of 48.3% after the final cycle, demonstrating its sustainability. However, further optimization is needed to prevent the gradual decline in adsorption efficiency and to meet the regulatory standards. This method offers a sustainable, effective solution for 3-MCPDE reduction, highlighting the potential of MOF-based materials to enhance food safety by reducing harmful contaminants in edible oils and food products
Sub-lethal pesticide exposure interferes with honey bee memory of learnt colours
No full textNeonicotinoid pesticide use has increased around the world despite accumulating evidence of their potential detrimental sub-lethal effects on the behaviour and physiology of bees, and its contribution to the global decline in bee health. Whilst flower colour is considered as one of the most important signals for foraging honey bees (Apis mellifera), the effects of pesticides on colour vision and memory retention in a natural setting remain unknown. We trained free flying honey bee foragers by presenting artificial yellow flower feeder, to an unscented artificial flower patch with 6 different flower colours to investigate if sub-lethal levels of imidacloprid would disrupt the acquired association made between the yellow flower colour from the feeder and food reward. We found that for doses higher than 4 % of LD50 value, the foraging honey bees no longer preferentially visited the yellow flowers within the flower patch and instead, we suspect, reverted back to baseline foraging preferences, with a complete loss of the yellow preference. Our honey bee colour vision modelling indicates that discriminating the yellow colour from the rest should have been easy cognitive task. Pesticide exposure also resulted in a significant increase in Lop1, UVop, and Blop, and a decrease in CaMKII and CREB gene expression. Our results suggest that memory loss is the most plausible mechanism to explain the alteration of bee foraging colour preference. Across bees, colour vision is highly conserved and is essential for efficient pollination services. Therefore, our findings have important implications for ecosystem health and agricultural services world-wide
PhosNetVis: a web-based tool for fast kinase-substrate enrichment analysis and interactive 2D/3D network visualizations of phosphoproteomics data
No full textProtein phosphorylation involves the reversible modification of a protein (substrate) residue by another protein (kinase). Liquid chromatography-mass spectrometry studies are rapidly generating massive protein phosphorylation datasets across multiple conditions. Researchers then must infer kinases responsible for changes in phosphosites of each substrate. However, tools that infer kinase-substrate interactions (KSIs) are not optimized to interactively explore the resulting large and complex networks, significant phosphosites, and states. There is thus an unmet need for a tool that facilitates user-friendly analysis, interactive exploration, visualization, and communication of phosphoproteomics datasets. We present PhosNetVis, a web-based tool for researchers of all computational skill levels to easily infer, generate, and interactively explore KSI networks in 2D or 3D by streamlining phosphoproteomics data analysis steps within a single tool. PhostNetVis lowers barriers for researchers by rapidly generating high-quality visualizations to gain biological insights from their phosphoproteomics datasets. It is available at https://gumuslab.github.io/PhosNetVis/
Influence of strand size and morphology on the mechanical performance of recycled CF/PEKK composites: harnessing waste for aerospace secondary load-bearing applications
No full textThe flexibility and precision of automated fiber placement (AFP) have made it a standard methodology in the aviation industry. However, the use of continuous slit tapes along component lengths generates significant waste. This waste presents an opportunity for recycling into secondary load-bearing structures, particularly in applications where components are not subjected to extreme working conditions. In this study, carbon fiber-reinforced polyetherketoneketone (CF/PEKK) strands are recycled into randomly oriented strand (ROS) panels using a cost-effective, vacuum-assisted hot press process while maintaining aerospace-quality standards. Both long and short strand lengths, as well as shredded strands mimicking real-life industrial waste, are analyzed for their mechanical performance and geometric stability. Mechanical properties of the recycled CF/PEKK composites are evaluated through tensile, shear, compression, Izod impact, and dynamic mechanical analysis (DMA), using digital image correlation (DIC) for precise measurements. Additionally, topological 3D scanning is used to assess the geometric stability of the panels. Results indicate that short strands offer superior mechanical properties, while shredded strands perform comparably. This study makes a unique contribution by demonstrating the effective recycling of slit tape waste into high-performance composite materials, advancing sustainable practices in aerospace applications
How does training improve individual forecasts? Modeling differences in compensatory and non-compensatory biases in geopolitical forecasts
No full textBiases in human forecasters lead to poor calibration. We assess how formal training affects two types of bias in probabilistic forecasts of binary outcomes. Compensatory bias occurs when underestimation in one range of probabilities (e.g., less than 50%) is accompanied by overestimation in the opposite range. Non-compensatory bias occurs when the direction of misestimation is consistent throughout the entire range of probabilities. We present a new approach to modeling probabilistic forecasts to determine the extent and direction of compensatory and non-compensatory biases. Using data from the Good Judgment Project, we model the effects of training (randomly assigned) on the calibration of 39,481 initial forecasts from 851 forecasters across two years of the contest. The forecasts exhibit significant indications of both compensatory and non-compensatory biases across all forecasters. Training significantly reduces the compensatory bias in both years. It reduces the non-compensatory bias only in the second year of the contest