Constructing Stable Polyvinyl Alcohol/Gelatin/Cellulose Nanocrystals Composite Electrospun Membrane with Excellent Filtration Efficiency for PM2.5.

Considering the high demand for air quality, the development of biomass-based air filtration membranes with high air filtration efficiency and good stability is an urgent task. In this work, polyvinyl alcohol (PVA), gelatin (GA), and cellulose nanocrystals (CNC) were mixed and prepared into a membrane through an electrospinning method for air filtration. After a hydrophobic modification, the modified PVA/GA/CNC composite membrane showed excellent filtration efficiency for PM2.5 (97.65%) through the internal three-dimensional structure barrier and the electrostatic capture effect of the CNC with a negative charge, as well as a low-pressure drop (only 50 Pa). In addition, the modified PVA/GA/CNC composite membrane had good mechanical properties (maximum tensile fracture rate of 78.3%) and high stability (air filtration efficiency of above 90% after five wash-filter cycles and a high-temperature treatment at 200 °C). It is worth noting that the whole preparation process is completed without organic solvents, putting forward a new strategy for the construction of green air filtration membranes.

Coping style and mental health amid the first wave of the COVID-19 pandemic: a culture-moderated meta-analysis of 44 nations.

In the first wave of the COVID-19 pandemic, the rapid transmission of a novel virus and the unprecedented disease-mitigation measures have elicited considerable stress in many countries worldwide. Coping with pandemic stress may be differentially related to psychological symptoms across countries characterised by distinct cultural values. This study aimed to: (a) synthesise the literature by investigating the associations between some major types of coping style and psychological symptoms, and (b) investigate the moderating effects of culture on these associations. We performed a three-level random-effects meta-analysis, which included 151 independent samples from 44 countries across eight world regions (n = 137,088, 66% women, Mage = 36.08). For both problem-focused and avoidant coping styles, their hypothesised associations with psychological symptoms were robust across the countries (anxiety: rs = -.11 and .31; depression: rs = -.19 and .33; ps < .0001). For both emotion-focused and social support seeking styles, their associations with psychological symptoms were moderated by two Hofstede's cultural dimensions: uncertainty avoidance (intolerance of ambiguity) and masculinity (concern for achievement and success). The hypothesised negative coping style-symptom associations were found only in the countries with lower levels of uncertainty avoidance or masculinity, but opposite patterns of findings were found in those with higher levels of either of these two cultural dimensions.

A meta-analytic review of the associations between dimensions of religious coping and psychological symptoms during the first wave of the COVID-19 pandemic.

Introduction: In the first wave of the COVID-19 pandemic, the unknown etiology and treatment of the highly transmissible coronavirus posed considerable threats to public mental health. Many people around the globe turned to religion as an attempt to mitigate their heightened psychological distress, but mixed findings have been obtained regarding the association between the use of religious coping and two psychological symptoms-anxiety and depressive symptoms-widely reported in the initial wave. Objective: The present meta-analysis was conducted to resolve the empirical inconsistency by synthesizing this body of studies and identifying both individual and national-level factors that accounted for the inconsistent findings. Methods: Following PRISMA guidelines, the literature search and data screening procedures yielded 42 eligible studies, with 25,438 participants (58% females, average age = 36.50 years) from 24 countries spanning seven world regions. Results: Overall, the results showed that only negative religious coping was positively associated with psychological symptoms (r = 0.2886, p < 0.0001). Although the associations of both general and positive religious coping with psychological symptoms were non-significant (rs = 0.0425 and -0.0240, ps > 0.39), the moderation analysis revealed significant positive associations between positive religious coping and psychological symptoms in two demographic groups who experienced greater pandemic distress than their counterparts: younger participants and female participants. Discussion: This meta-analysis provides a nuanced understanding of the complex nature of religious coping in the initial wave of the COVID-19 pandemic when the levels of public anxiety and stress were heightened. The exclusive use of religious coping may not be associated with low levels of psychological symptoms, implying the importance of supplementing the deployment of this strategy with an array of other strategies. Therapists of mental health interventions should show their clients how to make good use of positive religious coping together with other strategies, and how to avoid the use of negative religious coping, to handle their psychological problems. Systematic review registration: https://osf.io/shb32/.

Fabrication of Phytic Acid/Urea Co-Modified Bamboo Biochar and Its Application as Green Flame Retardant for Polylactic Acid Resins.

It is of great significance to develop green, sustainable additives to improve the thermal stability and flame retardancy of biopolymers. In this work, a synergistic modification of P/N elements to bamboo biochar (mBC) was successfully achieved by grafting a reaction of phytic acid and urea with preoxidized bamboo biochar. Fourier transform infrared spectroscopy, X-ray diffraction, nuclear magnetic resonance and scanning electron microscope determinations of the mBC demonstrated a successive grafting of phytic acid and urea to the originally porous surface. The ground mBC was blended with polylactic acid (PLA) to prepare mBC/PLA composites by extrusion and hot pressing. Mechanical strength studies showed a compromise in rigidity, which might originate from the mBC overdose and its limited miscibility with the resin. The thermogravimetric results supported the fact that the enhancement of thermal stability and flame retardancy of the composites with the mBC dosage, which showed that the mBC dosage in the PLA composites was not only lower than that of the conventional flame retardants, but also outperformed the counterparts using BC modified by inorganic phosphoric acid and urea. The mBC was prone to accelerate the earlier decomposition of the composites (30 °C lower in decomposition) and generate a continuous, dense residual carbon layer, which provides an effective shield resisting the mass and heat transfer between the combustion area and the underlying composite matrix. Only 10 wt% of mBC dosage could achieve a V-0 rating (UL94) for the composite, with a higher limiting oxygen index up to 28.3% compared to 20.7% for that of the virgin PLA; the cone colorimetric results also suggested that the flame retardancy had been greatly improved for all composites. In this work, biobased P-/N-containing bamboo biochar would be expected as a nontoxic biochar-based flame retardant that serves as green filler in polymer composites.

Synthesis of P-/N-Containing Bamboo-Activated Carbon toward Enhanced Thermal Stability and Flame Retardancy of Polylactic Acid.

A P-/N-containing bamboo-activated carbon (BACm) was successfully synthesized by steam activation of bamboo charcoal and chemical grafting to as-prepared activated carbon using the reaction of phosphoric acid and urea. Characterizations of BACm presented a synergistic grafting of P and N elements to the BAC surface. The BACm was further loaded in a polylactic acid (PLA) matrix to prepare BACm/PLA composites. Mechanical strength study showed tensile strength dropped from 75.19 MPa to 61.30 MPa, and tensile modulus from 602.49 MPa to 375.56 MPa, suggesting a rigidity reduction and deformation resistance enhancement owing to the roughened surface of BACm that interlocked with the polymer. The thermogravimetric analysis showed that the carbon residue rate of BACm dramatically fell to 49.25 wt.% in contrast to 88.28% for the control BAC, and cone calorimeter measurements confirmed the enhancement of flame retardancy of the composites with BACm loading, and the carbon residue rate increased progressively with BACm loading in the composites, notably up to 8.60 wt.% for the BAC/PLA9 composite, which outweighed the theoretical residue rate by more than 50%. The elemental analysis also confirmed rich P/N levels of the dense carbon residue layer that could perform synergistically and effectively in fire suppression. The BACm tended to stimulate the earlier decomposition of the composites and formed a continuous residual carbon layer which functioned as an effective barrier hindering the mass and heat transfer between the combustion zone and the underlying matrix. Moreover, 9 wt.% of BACm loading could attain a V-0 rating (UL94) for the composite with an improved limiting oxygen index up to 31.7%. The biomass-based modified activated carbon in this work could be considered as an alternative flame retardant in polymer applications.

In Situ Dry Chemical Synthesis of Nitrogen-Doped Activated Carbon from Bamboo Charcoal for Carbon Dioxide Adsorption.

In this work, nitrogen-doped bamboo-based activated carbon (NBAC) was in situ synthesized from simply blending bamboo charcoal (BC) with sodamide (SA, NaNH2) powders and heating with a protection of nitrogen flow at a medium temperature. The elemental analysis and X-ray photoelectron spectra of as-synthesized NBAC showed quite a high nitrogen level of the simultaneously activated and doped samples; an abundant pore structure had also been determined from the NBACs which has a narrow size distribution of micropores (<2 nm) and favorable specific surface area that presented superb adsorption performance. The fcarbon dioxide (CO2) adsorption of the NBACs was measured at 0 °C and 25 °C at a pressure of 1 bar, whose capture capacities reached 3.68-4.95 mmol/g and 2.49-3.52 mmol/g, respectively, and the maximum adsorption could be observed for NBACs fabricated with an SA/BC ratio of 3:1 and activated at 500 °C. Further, adsorption selectivity of CO2 over N2 was deduced with the ideal adsorbed solution theory ((IAST), the selectivity was finally calculated which ranged from 15 to 17 for the NBACs fabricated at 500 °C). The initial isosteric heat of adsorption (Qst) of NBACs was also determined at 30-40 kJ/mol, which suggested that CO2 adsorption was a physical process. The results of ten-cycle adsorption-desorption experimentally confirmed the regenerated NBACs of a steady CO2 adsorption performance, that is, the as-synthesized versatile NBAC with superb reproducibility makes it a perspective candidate in CO2 capture and separation application.

Public Emotional and Coping Responses to the COVID-19 Infodemic: A Review and Recommendations.

Since its onset in early 2020, the coronavirus disease 2019 (COVID-19) pandemic has adversely affected not only the physical but also the mental health of people worldwide. Healthcare professionals and laypersons have sought to learn more about this novel and highly transmissible disease to better understand its etiology, treatment, and prevention. However, information overload and misinformation related to COVID-19 have elicited considerable public anxiety and created additional health threats. Collectively, these problems have been recognized by the World Health Organization as an "infodemic." This review provides an overview of the global challenges posed by the COVID-19 infodemic, and used the psychological entropy model as a guiding framework to explicate the potential causes of the infodemic and identify potential solutions to mitigate impacts on public health. We first examine the role of anxiety in information processing and then delineate the adverse impacts of the infodemic. Finally, we propose strategies to combat the infodemic at the public, community, and individual levels.