A Critical Discourse Analysis of the Microstructure of Covid-19 Health-Protocol Advertisements in Tourist Facilities

To alleviate the impact of the Covid-19 pandemic on tourism, tourist facilities in Bali are informing visitors of the relevant health protocols, using posters to describe the appropriate behaviours. Using critical discourse analysis, this study examines the microstructure of the texts in these posters to identify their semantic, syntactic, lexical, and rhetorical elements. The study findings show that the semantic aspects consist of background, intention, and detail. The syntactic elements involve coherence and the use of the pronouns 'you' and 'we', and of the imperative, and the declarative. The lexical aspects include abbreviations and vocabulary, related to the health protocol. The textual messages are delivered in official language, supported by pictures and photographs.

Price leadership in China's oil futures market: take two

This study is the first to conduct a comprehensive analysis of the price discovery and market liquidity aspects of China's crude oil futures market compared to WTI and Brent. With intraday-day data consolidated into 1-second intervals and three measures of price discovery, we find that China's crude oil futures market reports encouraging signs in terms of price discovery and efficiency, also showing great resilience during the COVID-19 pandemic. The market has obtained a dominant role in price discovery relative to WTI and Brent during its day trading hours, and has almost caught up with Brent in terms of market liquidity. © 2023 Informa UK Limited, trading as Taylor & Francis Group.

Feasibility of diffusion-tensor and correlated diffusion imaging for studying white-matter microstructural abnormalities: Application in COVID-19.

There has been growing attention on the effect of COVID-19 on white-matter microstructure, especially among those that self-isolated after being infected. There is also immense scientific interest and potential clinical utility to evaluate the sensitivity of single-shell diffusion magnetic resonance imaging (MRI) methods for detecting such effects. In this work, the performances of three single-shell-compatible diffusion MRI modeling methods are compared for detecting the effect of COVID-19, including diffusion-tensor imaging, diffusion-tensor decomposition of orthogonal moments and correlated diffusion imaging. Imaging was performed on self-isolated patients at the study initiation and 3-month follow-up, along with age- and sex-matched controls. We demonstrate through simulations and experimental data that correlated diffusion imaging is associated with far greater sensitivity, being the only one of the three single-shell methods to demonstrate COVID-19-related brain effects. Results suggest less restricted diffusion in the frontal lobe in COVID-19 patients, but also more restricted diffusion in the cerebellar white matter, in agreement with several existing studies highlighting the vulnerability of the cerebellum to COVID-19 infection. These results, taken together with the simulation results, suggest that a significant proportion of COVID-19 related white-matter microstructural pathology manifests as a change in tissue diffusivity. Interestingly, different b-values also confer different sensitivities to the effects. No significant difference was observed in patients at the 3-month follow-up, likely due to the limited size of the follow-up cohort. To summarize, correlated diffusion imaging is shown to be a viable single-shell diffusion analysis approach that allows us to uncover opposing patterns of diffusion changes in the frontal and cerebellar regions of COVID-19 patients, suggesting the two regions react differently to viral infection.

Antibacterial anodic aluminium oxide-copper coatings on aluminium alloys: preparation and long-term antibacterial performance

Anodic aluminium oxide-copper (AAO-Cu) coatings were prepared on the aluminium (Al) alloy substrates to attain excellent antibacterial performance and mechanical stability. The nanoporous AAO interlayer was ob-tained by anodic oxidation with an outer Cu layer deposited by electroplating. The intermediate zone (similar to 2 mu m thick) of the AAO-Cu coating plays a significant role in the coating properties. The interlocking effect in the AAO-Cu intermediate zone significantly enhances the coating adhesion and curbs the coating defoliation. The anti-bacterial tests show that the AAO-Cu zone provides excellent antibacterial ability even when the outer Cu coating was removed. The sustained antibacterial rate of the AAO-Cu intermediate zone against E. coli exceeded 95%. The Cu ions released from the embedded Cu in the nanoporous AAO structure ensure a long-term antibacterial capability. This coating system can be promoted in a large wide range of antibacterial products in public.

Identifying cerebral microstructural changes in patients with COVID-19 using MRI: A systematic review.

Coronavirus disease 2019 (COVID-19) is an epidemic viral disease caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Despite the excessive number of neurological articles that have investigated the effect of COVID-19 on the brain from the neurological point of view, very few studies have investigated the impact of COVID-19 on the cerebral microstructure and function of the brain. The aim of this study was to summarize the results of the existing studies on cerebral microstructural changes in COVID-19 patients, specifically the use of quantitative volumetric analysis, blood oxygen level dependent (BOLD), and diffusion tensor imaging (DTI). We searched PubMed/MEDLINE, ScienceDirect, Semantic Scholar, and Google Scholar from December 2020 to April 2022. A well-constructed search strategy was used to identify the articles for review. Seven research articles have met this study's inclusion and exclusion criteria, which have applied neuroimaging tools such as quantitative volumetric analysis, BOLD, and DTI to investigate cerebral microstructure changes in COVID-19 patients. A significant effect of COVID-19 was found in the brain such as hypoperfusion of cerebral blood flow, increased gray matter (GM) volume, and reduced cortical thickness. The insula and thalamic radiation were the most frequent GM region and white matter tract, respectively, that are involved in SARS-CoV-2. COVID-19 was found to be associated with changes in cerebral microstructures. These abnormalities in brain areas might lead to be associated with behaviors, mental and neurological alterations that need to be considered carefully in future studies.

Structural Characteristic of Fullerene C 60 and its Sorptive Properties

The pandemic situation associated with the occurrence of COVID-19 has necessitated the initiation or renewal of research activities aimed at the possibility of using materials that will have very good post-accident properties. One of the materials that have been developed, tested and applied in the past has been materials based on the spherical fullerene C 60 molecule. A microstructure using REM and SEM and sorptive properties of fullerene C 60 for gases of toluene with the employment of a QCM detector has been studied. Obtained micrographs are discussed in relation to a possible spatial arrangement at the molecular level. The envisaged solution aims to develop a sensor that, due to its surface properties, would be useful for the detection of gas and liquid phases of chemical warfare agents and industrial chemicals. It is envisaged that the surface layer consisting of fullerene C 60 will be universally applicable, reusable and low cost and low maintenance. © 2022 Challenges to National Defence in Contemporary Geopolitical Situation. All rights reserved.

Effects of different stirrer modes on the physicochemical properties of vegetables during cooking

The coronavirus disease-19 (COVID-19) pandemic caused dietary changes. Humans reduced social activities to prevent the spread of COVID-19, which led to increasing demand for machines to help cook. This work studies the effect of different stirrer modes on the texture of celery, asparagus, green peppers, and spinach during the cooking process and the functional loss of components in vegetables by measuring the changes in vitamin C, total polyphenols, and total flavonoids. The results showed that colour changes and loss of nutrients in each vegetable varied under different stirrer modes. Stirring was found to be the best mode for cooking all four vegetables. In addition, there was a positive correlation between the a* value and functional components during the cooking process, which means that the colour difference and nutritional loss of vegetables can be modulated together. This study provides theoretical guidance for developing the stirring unit in a cooking machine.

Effects of different stirrer modes on the physicochemical properties of vegetables during cooking

Summary The coronavirus disease‐19 (COVID‐19) pandemic caused dietary changes. Humans reduced social activities to prevent the spread of COVID‐19, which led to increasing demand for machines to help cook. This work studies the effect of different stirrer modes on the texture of celery, asparagus, green peppers, and spinach during the cooking process and the functional loss of components in vegetables by measuring the changes in vitamin C, total polyphenols, and total flavonoids. The results showed that colour changes and loss of nutrients in each vegetable varied under different stirrer modes. Stirring was found to be the best mode for cooking all four vegetables. In addition, there was a positive correlation between the a* value and functional components during the cooking process, which means that the colour difference and nutritional loss of vegetables can be modulated together. This study provides theoretical guidance for developing the stirring unit in a cooking machine. [ FROM AUTHOR]

Probability of informed trading during the COVID-19 pandemic: the case of the Romanian stock market.

Using data from the Bucharest Stock Exchange, we examine the factors influencing the probability of informed trading (PIN) during February-October 2020, a COVID-19 pandemic period. Based on an unconditional quantile regression approach, we show that PIN exhibit asymmetric dependency with liquidity and trading costs. Furthermore, building a customized database that contains all insider transactions on the Bucharest Stock Exchange, we reveal that these types of orders monotonically increase the information asymmetry from the 50th to the 90th quantile throughout the PIN distribution. Finally, we bring strong empirical evidence associating the level of information asymmetry to the level of fake news related to the COVID-19 pandemic. This novel result suggests that during episodes when the level of PIN is medium to high (between 15 and 50%), any COVID-19 related news classified as misinformation released during the lockdown period, is discouraging informed traders to place buy or sell orders conditioned by their private information.

Engineered self-healing single-cavity microcapsules for pulsatile release of drug delivery

A wide range of polymer-based drug delivery systems have been reported for the treatment of various diseases. However, the dosing regimen of many drugs, such as stimulator of interferon genes agonists, programmed cell death protein-1 antibodies, and coronavirus disease 2019 vaccines, consists of repeated intratumoral or intramuscular injections. These repeated administrations may lead to poor adherence, thus resulting in compromised therapeutic outcomes and increased financial burden. Here, we developed a multidose drug delivery platform by engineering polylactic-co-glycolic acid (PLGA) with different molecular weights into self-healing single-cavity microcapsules (SSM). This approach showed a flexible collocation strategy to achieve customized pulsatile drug release and was fully degradable with good safety. Notably, this single-injection delivery system contains only PLGA, holding great promise for clinical translation. © 2022 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences

Brownian Motion Fractal Nature Frontiers Within the Matter

One of the main motivations for our research was to find a connection between the Brownian motion of microorganisms within fractal nature, with the idea of developing an appropriate procedure and method to control the microorganism's motion direction and predict the position of the microorganism in time. In this paper, we have followed the results of the very rear microorganism's motion sub-microstructures in the experimental microstructure analysisFractals already observed and published. All of these data have been good basis to describe the motion trajectory by time interval method and fractals. We successfully defined the diagrams in two and three-dimensions and we were able to establish the control of Brownian chaotic motion as a bridge between chaotic disorders to control disorder. This significant study opens a new possibility for future investigation and the new potential of total control of the microorganism motion. These perspectives and findings provide significant data for getting more information from these bio systems. They can also be applied, based on self-similarities and biomimetics, to particle physical systemMatterFractalss and matter, generally. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Hydrogenated Boron Phosphide THz-Metamaterial-Based Biosensor for Diagnosing COVID-19: A DFT Coupled FEM Study.

Recent reports focus on the hydrogenation engineering of monolayer boron phosphide and simultaneously explore its promising applications in nanoelectronics. Coupling density functional theory and finite element method, we investigate the bowtie triangle ring microstructure composed of boron phosphide with hydrogenation based on structural and performance analysis. We determine the carrier mobility of hydrogenated boron phosphide, reveal the effect of structural and material parameters on resonance frequencies, and discuss the variation of the electric field at the two tips. The results suggest that the mobilities of electrons for hydrogenated BP monolayer in the armchair and zigzag directions are 0.51 and 94.4 cm2·V-1·s-1, whereas for holes, the values are 136.8 and 175.15 cm2·V-1·s-1. Meanwhile, the transmission spectra of the bowtie triangle ring microstructure can be controlled by adjusting the length of the bowtie triangle ring microstructure and carrier density of hydrogenated BP. With the increasing length, the transmission spectrum has a red-shift and the electric field at the tips of equilateral triangle rings is significantly weakened. Furthermore, the theoretical sensitivity of the BTR structure reaches 100 GHz/RIU, which is sufficient to determine healthy and COVID-19-infected individuals. Our findings may open up new avenues for promising applications in the rapid diagnosis of COVID-19.

Synthesis of Silver Nanoparticles-Modified Graphitic Carbon Nitride Nanosheets for Highly Efficient Photocatalytic Hydrogen Peroxide Evolution.

As a promising metal-free photocatalyst, graphitic carbon nitride (g-C3N4) is still limited by insufficient visible light absorption and rapid recombination of photogenerated carriers, resulting in low photocatalytic activity. Here, we adjusted the microstructure of the pristine bulk-g-C3N4 (PCN) and further loaded silver (Ag) nanoparticles. Abundant Ag nanoparticles were grown on the thin-layer g-C3N4 nanosheets (CNNS), and the Ag nanoparticles decorated g-C3N4 nanosheets (Ag@CNNS) were successfully synthesized. The thin-layer nanosheet-like structure was not only beneficial for the loading of Ag nanoparticles but also for the adsorption and activation of reactants via exposing more active sites. Moreover, the surface plasmon resonance (SPR) effect induced by Ag nanoparticles enhanced the absorption of visible light by narrowing the band gap of the substrate. Meanwhile, the composite band structure effectively promoted the separation and transfer of carriers. Benefiting from these merits, the Ag@CNNS reached a superior hydrogen peroxide (H2O2) yield of 120.53 µmol/g/h under visible light irradiation in pure water (about 8.0 times higher than that of PCN), significantly surpassing most previous reports. The design method of manipulating the microstructure of the catalyst combined with the modification of metal nanoparticles provides a new idea for the rational development and application of efficient photocatalysts.

The Composites of Polyamide 12 and Metal Oxides with High Antimicrobial Activity.

The lack of resistance of plastic objects to various pathogens and their increasing activity in our daily life have made researchers develop polymeric materials with biocidal properties. Hence, this paper describes the thermoplastic composites of Polyamide 12 mixed with 1-5 wt % of the nanoparticles of zinc, copper, and titanium oxides prepared by a twin-screw extrusion process and injection moulding. A satisfactory biocidal activity of polyamide 12 nanocomposites was obtained thanks to homogenously dispersed metal oxides in the polymer matrix and the wettability of the metal oxides by PA12. At 4 wt % of the metal oxides, the contact angles were the lowest and it resulted in obtaining the highest reduction rate of the Escherichia coli (87%), Candida albicans (53%), and Herpes simplex 1 (90%). The interactions of the nanocomposites with the fibroblasts show early apoptosis (11.85-27.79%), late apoptosis (0.81-5.04%), and necrosis (0.18-0.31%), which confirms the lack of toxicity of used metal oxides. Moreover, the used oxides affect slightly the thermal and rheological properties of PA12, which was determined by oscillatory rheology, thermogravimetric analysis, and differential scanning calorimetry.

Waste Polymer and Lubricating Oil Used as Asphalt Rheological Modifiers.

The hazards of plastic waste (PW) from polymers (e.g., polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyvinyl chloride (PVC), nylon, polystyrene (PS), etc.), the mechanism of its spread in general, and its ubiquity in our daily lives as a continuously and/or frequently expelled product are a crisis of the twenty-first century, as reported by the United Nations in 2019, especially after the outbreak of the COVID-19 pandemic. This research included the process of modifying the rheological properties of asphalt to obtain asphalt suitable for use in a high-humidity atmosphere. The Iraqi climate is characterized by heat that reaches the point of harshness in the summer and coldness that falls below zero on some winter days. From this point of view, our recent study focuses mainly on making rheological and chemical modifications to asphalt using spent polymeric materials and used lubricating oils (ULO), thus achieving two important goals, namely obtaining asphalt with rheological properties resistant to the Iraqi atmosphere as well as eliminating both solid and liquid environmental pollutants. The microstructure and morphology of the designed patches were characterized using scanning electron microscopy (SEM) to indicate phase composition.

Decontamination Assessment of Nanofiber-based N95 Masks.

As the world battles with the outbreak of the novel coronavirus, it also prepares for future global pandemics that threaten our health, economy, and survivor. During the outbreak, it became evident that use of personal protective equipment (PPE), specially face masks, can significantly slow the otherwise uncontrolled spread of the virus. Nevertheless, the outbreak and its new variants have caused shortage of PPE in many regions of the world. In addition, waste management of the enormous economical and environmental footprint of single use PPE has proven to be a challenge. Therefore, this study advances the theme of decontaminating used masks. More specifically, the effect of various decontamination techniques on the integrity and functionality of nanofiber-based N95 masks (i.e. capable of at least filtering 95% of 0.3 µm aerosols) were examined. These techniques include 70% ethanol, bleaching, boiling, steaming, ironing as well as placement in autoclave, oven, and exposure to microwave (MW) and ultraviolet (UV) light. Herein, filtration efficiency (by Particle Filtration Efficiency equipment), general morphology, and microstructure of nanofibers (by Field Emission Scanning Electron microscopy) prior and after every decontamination technique were observed. The results suggest that decontamination of masks with 70% ethanol can lead to significant unfavorable changes in the microstructure and filtration efficiency (down to 57.33%) of the masks. In other techniques such as bleaching, boiling, steaming, ironing and placement in the oven, filtration efficiency dropped to only about 80% and in addition, some morphological changes in the nanofiber microstructure were seen. Expectedly, there was no significant reduction in filtration efficiency nor microstructural changes in the case of placement in autoclave and exposure to the UV light. It was concluded that, the latter methods are preferable to decontaminate nanofiber-based N95 masks.

Widespread white matter oedema in subacute COVID-19 patients with neurological symptoms.

While neuropathological examinations in patients who died from COVID-19 revealed inflammatory changes in cerebral white matter, cerebral MRI frequently fails to detect abnormalities even in the presence of neurological symptoms. Application of multi-compartment diffusion microstructure imaging (DMI), that detects even small volume shifts between the compartments (intra-axonal, extra-axonal and free water/CSF) of a white matter model, is a promising approach to overcome this discrepancy. In this monocentric prospective study, a cohort of 20 COVID-19 inpatients (57.3 ± 17.1 years) with neurological symptoms (e.g. delirium, cranial nerve palsies) and cognitive impairments measured by the Montreal Cognitive Assessment (MoCA test; 22.4 ± 4.9; 70% below the cut-off value <26/30 points) underwent DMI in the subacute stage of the disease (29.3 ± 14.8 days after positive PCR). A comparison of whole-brain white matter DMI parameters with a matched healthy control group (n = 35) revealed a volume shift from the intra- and extra-axonal space into the free water fraction (V-CSF). This widespread COVID-related V-CSF increase affected the entire supratentorial white matter with maxima in frontal and parietal regions. Streamline-wise comparisons between COVID-19 patients and controls further revealed a network of most affected white matter fibres connecting widespread cortical regions in all cerebral lobes. The magnitude of these white matter changes (V-CSF) was associated with cognitive impairment measured by the MoCA test (r = -0.64, P = 0.006) but not with olfactory performance (r = 0.29, P = 0.12). Furthermore, a non-significant trend for an association between V-CSF and interleukin-6 emerged (r = 0.48, P = 0.068), a prominent marker of the COVID-19 related inflammatory response. In 14/20 patients who also received cerebral 18F-FDG PET, V-CSF increase was associated with the expression of the previously defined COVID-19-related metabolic spatial covariance pattern (r = 0.57; P = 0.039). In addition, the frontoparietal-dominant pattern of neocortical glucose hypometabolism matched well to the frontal and parietal focus of V-CSF increase. In summary, DMI in subacute COVID-19 patients revealed widespread volume shifts compatible with vasogenic oedema, affecting various supratentorial white matter tracts. These changes were associated with cognitive impairment and COVID-19 related changes in 18F-FDG PET imaging.

Evaluation of the Degradation of Materials by Exposure to germicide UV-C Light through Colorimetry, Tensile Strength and Surface Microstructure Analyses

Due to the COVID19 pandemic, solutions to automate disinfection using UV-C combined with mobile robots are beginning to be explored. It has been proved that the use of these systems highly reduces the risk of contagion. However, its use in real applications is not being as rapid as it needs to be. One of the main market input barriers is the fear of degrading facilities. For this reason, it is crucial to perform a detailed study on the degradation effect of UV-C light on inert materials. This experimental study proves that, considering exposition times equivalent to several work years in hospital rooms, only the appearance of the material is affected, but not their mechanical functionalities. This relevant result could contribute to accelerate the deployment of these beneficial disinfection technologies. For that purpose, a colorimetry test, tensile strength test, and analysis of the surface microstructure were carried out. The results showed that polymers tend to turn yellow, while fabrics lose intensity depending on the color. Red is hardly affected by UV-C, but blue and green are. Thus, this study contributes to the identification of the best materials and colors to be used in rooms subjected to disinfection processes. In addition, it is shown how the surface microstructure of the materials is altered in most of the materials, but not the tensile strength of the fabrics.

Experimental study on the monotonic mechanical behavior of completely decomposed granite soil reinforced by disposable face-mask chips.

In response to the global outbreak of the coronavirus pandemic (COVID-19), a staggering amount of personal protective equipment, such as disposable face masks, has been used, leading to the urgent environmental issue. This study evaluates the feasibility of mask chips for the soil reinforcement, through triaxial tests on samples mixed with complete decomposed granite (CDG) and mask chips (0%, 0.3%, 0.5%, 1%, 5% by volume). The experimental results show that adding a moderate volumetric amount of mask chips (0.3%-1%) improves the soil strength, especially under high confining pressure. The optimum volumetric content of mask chips obtained by this study is 0.5%, raising the peak shear strength up to 22.3% under the confining stress of 120 kPa. When the volumetric content of mask chips exceeds the optimum value, the peak shear strength decreases accordingly. A limited amount of mask chips also increases the elastic modulus and makes the volumetric response more dilative. By contrast, excessive mask chips create additional voids and shift the strong soil-mask contacts to weak mask-mask contacts. The laser scanning microscope (LSM) and scanning electron microscope (SEM) images on the typical samples demonstrate the microstructure of mask fibers interlocking with soil particles, highly supporting the macro-scale mechanical behavior.

Reconnoitering Price Discovery and Market Efficiency Process Among Indian HRITHIK Stocks Using VAR Causality and VECM Tests

The purpose of this paper was to ascertain the impact of futures prices on market efficiency and price discovery in India in HRITHIK stocks from 2017 – 2020. The paper investigated the impact of futures prices on market efficiency and price discovery in India in HRITHIK stocks from 2017 – 2020. The current study comprised the daily near-month futures and daily spot closing prices of the HRITHIK stocks from January 1, 2017 – December 31, 2020, including the COVID-19 pandemic period. The paper used the vector autoregression (VAR) Engel Granger causality test to test the short-run equilibrium between spot and futures prices and the vector error correction model (VECM) to test for long-run equilibrium. A bi-directional relationship was found among six stocks out of the seven HRITHIK stocks. This confirmed the causal relationship that futures prices have on the spot prices. The VAR Engel Granger causality test indicated that the spot market narrowly led the futures despite a bi-directional flow of information. The results from the VECM model proved that the futures market acted as the dominant market in the long-run. Usually, researchers have leveraged sector-wise stocks to provide insights into the futures market’s function in price discovery. For the first time, HRITHIK stocks were analyzed to examine the cause-and-effect relationship for individual stocks in India’s futures and spot markets. The study considered the pre-COVID 19 and the post-COVID 19 periods and investigated the impact of the pandemic on these stocks. The research used daily closing prices of HRITHIK stocks;however, intraday data could be more conclusive and accurate in revealing the dominant market. © 2022, Associated Management Consultants Pvt. Ltd.. All rights reserved.