The electron transfer capacities (ETCs) of soil humic substances (HSs) are linked to the type and abundance of redox-active functional moieties in their structure. Natural temperature can affect the chemical structure of natural organic matter by regulating their oxidative transformation and degradation in soil. However, it is unclear if there is a direct correlation between ETC of soil HS and mean annual temperature. In this study, we assess the response of the electron-accepting and -donating capacities (EAC and EDC) of soil HSs to temperature by analyzing HSs extracted from soil set along glacial-interglacial cycles through loess-palaeosol sequences and along natural temperature gradients through latitude and altitude transects. We show that the EAC and EDC of soil HSs increase and decrease, respectively, with increasing temperature. Increased temperature facilitates the prevalence of oxidative degradation and transformation of HS in soils, thus potentially promoting the preferentially oxidative degradation of phenol moieties of HS or the oxidative transformation of electron-donating phenol moieties to electron-accepting quinone moieties in the HS structure. Consequently, the EAC and EDC of HSs in soil increase and decrease, respectively. The results of this study could help to understand biogeochemical processes, wherein the redox functionality of soil organic matter is involved in the context of increasing temperature.

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The trace metal selenium is in demand for health supplements to human and animal nutrition. We studied the reduction of selenite (SeO3 −2) to red elemental selenium by Rhodopseudomonas palustris strain N. This strain was cultured in a medium containing SeO3 −2 and the particles obtained from cultures were analyzed using transmission electron microscopy (TEM), energy dispersive microanalysis (EDX) and X ray diffraction analysis (XRD). Our results showed the strain N could reduce SeO3 −2 to red elemental selenium. The diameters of particles were 80–200 nm. The bacteria exhibited significant tolerance to SeO3 −2 up to 8.0 m mol/L concentration with an EC50 value of 2.4 m mol/L. After 9 d of cultivation, the presence of SeO3 2− up to 1.0 m mol/L resulted in 99.9% reduction of selenite, whereas 82.0% (p<0.05), 31.7% (p<0.05) and 2.4% (p<0.05) reduction of SeO3 −2 was observed at 2.0, 4.0 and 8.0 m mol/L SeO3 2− concentrations, respectively. This study indicated that red elemental selenium was synthesized by green technology using Rhodopseudomonas palustris strain N. This strain also indicated a high tolerance to SeO3 −2. The finding of this work will contribute to the application of selenium to human health.

Objective: The outbreak of COVID-19 that commenced in December 2019 in Wuhan, China, has caused extensive public health concerns and posed substantial challenges to health professionals, especially for those in the center of the epidemic. The current study aimed to assess the prevalence, related factors, and mechanism of acute stress disorder (ASD) among health professionals in Wuhan during this critical period. Methods: The study used a cross-sectional design. Self-administered questionnaires were distributed to the frontline health professionals in Wuhan hospitals from January 28 to February 1, 2020. Mental health-related measurements included ASD, depression, anxiety, conflict experiences, hostility, and psychosomatic symptoms. Structural equation modeling was used to analyze the factors associated with ASD among health professionals. Results: A total of 332 frontline health professionals were included in the analysis (mean [standard deviation] age = 32.21 [8.77] years; 78.0% women). ASD was a prominent mental health problem in the health professionals surveyed, with a prevalence of 38.3%. Anxiety (24.7%) and depression (20.2%) were also common. Structural equation modeling analyses revealed that emotional distress (i.e., anxiety and depressive symptoms) fully mediated the association between conflicts with ASD (the standardized indirect coefficient β = 0.47, p = .016). The most common reported symptom was chest pain (51.2%). ASD was significantly associated with psychosomatic symptoms. The majority (67.8%) reported being easily annoyed or irritated, and ASD was associated with hostility. Conclusions: During the COVID-19 outbreak, a substantial number of health professionals in Wuhan suffered from ASD. Furthermore, ASD was found to be associated with psychosomatic symptoms as well as the hostility. The poor mental health of health professionals has detrimental impacts both on the well-being of staff in health care systems and may adversely affect the quality of patient care. We call for interventions that aim to relieve the psychological and occupational stress. Considering that most of our participants were young, female frontline health professionals, the results may not be generalized to more heterogenous samples.

Conventional ion exchange resins with different functional groups were evaluated for their potential application in separating uranium U(VI) and thorium Th(IV) from rare earth elements RE(III). The resins studied comprised strong-and weak-base anion exchange resins, and strong-and weak-acid cation exchange resins. The selectivity of these resins to adsorb U(VI) and Th(IV) in the presence of selected RE(III) was examined in sulfuric acid media of varying concentrations. It was evident that the adsorption performance of the resins was acid concentration-dependent. Most candidate resins had potentially feasible selective adsorption at or below 0.1 mol/L H 2 SO 4 (pH ≥ 0.7). Within the group of anion exchange resins, both the strong-and weak-base resins exhibited a similar selectivity with U(VI) adsorbed in preference to RE(III). The difference between them was their adsorption of Th(IV). The weak-base resin with primary amine functional group demonstrated superior separation of Th(IV) from RE(III). For this resin, 78% of U(VI) and 68% of Th(IV) were adsorbed while RE(III) co-adsorption was less than 5% at 0.0005 mol/L H 2 SO 4 (pH 3). In the case of the strong-acid cation exchange resins, Th(IV) and RE(III) were adsorbed in preference to U(VI), i.e., RE(III) > Th(IV) >> U(VI). The weak-acid cation exchange resins, on the other hand, displayed limited adsorption of all elements.

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