Prediction of the dynamic distribution for Eucheuma denticulatum (Rhodophyta, Solieriaceae) under climate change in the Indo-Pacific Ocean

Submitted version (preprint).This is a preprint of an article published by Elsevier in Marine Environmental Research on 23.08.2022.Available online: doi.org/10.1016/j.marenvres.2022.105730submittedVersio

Resilience mediates the association between alexithymia and stress in Chinese medical students during the COVID-19 pandemic

Background Evidence indicates that medical students have had high rates of mental health problems, especially during the COVID-19 pandemic, which could be affected by alexithymia—a marked dysfunction in emotional awareness, social attachment and interpersonal relationships—and stress. However, psychological resilience might relieve alexithymia and stress levels.Aims This study aimed to investigate the role of resilience in alexithymia and stress in medical students.Methods A total of 470 medical students completed online and offline surveys, including the Toronto Alexithymia Scale-20 (TAS-20), the Connor-Davidson Resilience Scale (CD-RISC) and the College Student Stress Questionnaire (CSSQ). The data of five participants were excluded because of a lack of integrity. Mann-Whitney U test or Kruskal-Wallis test was used to compare group differences in the CD-RISC scores among categorical variables. Spearman correlation analysis was employed to evaluate the associations between resilience and alexithymia and between resilience and stress. Mediation analysis was used to test the mediating effect of resilience between alexithymia and stress.Results Of the medical students considered in the analysis, 382 (81.28%) were female and 88 (18.72%) were male. There was a significant negative correlation between the TAS-20 scores and the total and subtotal CD-RISC scores (p<0.001). The CSSQ scores also significantly negatively correlated with the total and subtotal CD-RISC scores (p<0.001). Resilience mediated the relationship between alexithymia and stress (total effect=1.044 7, p<0.001). The indirect effect of alexithymia significantly impacted stress through resilience (effect=0.167 0, 95% CI: 0.069 to 0.281).Conclusions Our findings suggest that resilience might effectively reduce alexithymia and stress. They also contributed to a better understanding of the mediating effects of resilience on alexithymia and stress during the COVID-19 pandemic. The evidence from these results encourages universities to focus on improving students’ resilience

Unanticipated Strong Blue Photoluminescence from Fully Biobased Aliphatic Hyperbranched Polyesters

Nonconventional fluorescent polymers without π-aromatic structure have attracted extensive interest in recent years. Hyperbranched polyesters are generally known because of their industrial applications; however, the luminescent properties of the polyester has not been reported. Herein, we synthesized a series of fully biobased aliphatic hyperbranched polyesters via a one-pot A₂ + B₃ esterification reaction. Intriguingly, the resultant hyperbranched polyesters carrying no conventional fluorescent units exhibited unexpected bright blue fluorescence under 365 nm UV light. It was found that the fluorescence intensity was enhanced with increasing solution concentrations and molecular weights of the polyesters. Moreover, the results suggested that the luminescence of polyesters could be controlled by solvents and metal ions. In particular, the fluorescence of the polyesters was extremely sensitive to Fe³⁺. More interesting is that the fluorescence of the polyesters showed an aggregation-induced enhanced emission in the mixture system. Notably, the resulting polyesters displayed a remarkably enhanced quantum yield (16.75%) as compared with that of other types of these polymers. Preliminary results demonstrate that clustering of the carbonyl groups is responsible for the unusual fluorescence in the aliphatic hyperbranched polyesters, namely, clustering-induced emission (CIE). This study provides a novel perspective for the design of biobased luminescent materials to new application areas

Zerovalent Selenium Adsorption Mechanisms on CaO Surface: DFT Calculation and Experimental Study

Zerovalent Se (Se atom and small Se₂ molecule) adsorption mechanisms on a CaO surface were studied by both density functional theory (DFT) calculations and adsorption experiments. Nonvalent Se adsorption on the CaO(001) surface was simulated using a slab model. The adsorption energy, adsorption structure, electron density clouds, and electron properties were calculated. Different Se surface coverages were investigated to elucidate the adsorption process. In the experiments, the Se adsorption products were prepared in a U-shaped quartz reactor at 300 °C. The properties were investigated by X-ray photoelectron spectroscopy (XPS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), field emission scanning electron microscopy/energy dispersive X-ray spectroscopy (FE-SEM/EDS), and X-ray diffraction (XRD), respectively. The experimental results match up with the DFT results, which reveal fundamental monochemisorption mechanisms of zerovalent Se on the CaO surface

Catalytic Oxidation and Adsorption of Elemental Mercury over CuCl₂‑Impregnated Sorbents

CuCl₂-impregnated sorbents were employed to remove elemental mercury from flue gas. Three carriers including neutral Al₂O₃, artificial zeolite, and activated carbon have been investigated in this research. The performances of these prepared sorbents have been tested in a bench-scale fixed-bed reactor under different simulated flue gas atmospheres and temperatures (333–573 K). CuCl₂-impregnated activated carbon showed the best adsorption ability. However, CuCl₂-impregnated neutral Al₂O₃ and zeolite have demonstrated an adsorption rate similar to that of CuCl₂-impregnated activated carbon in the early stage of the tests (5 min), and they achieved relatively high mercury oxidation efficiencies. These non-carbon sorbents could remarkably enhance the technoeconomical properties of mercury removal in coal-fired power plants and have great potentials in industrial application. The appropriate mercury capture temperature for these sorbents is 333–473 K. The possible mechanisms of elemental mercury oxidation have been discussed