Search

High entropy materials are becoming more and more popular in energy storage field of supercapacitors because of their unique structure and modulated functional characteristics, but their low conductivity and instability of electrode structure limit their further electrochemical performance. In this paper, we use polyethylene glycol (PEG) with different molecular weights to modify the surface morphology of the high entropy oxides (FeCoCrMnNi) 3 O 4 in an attempt to improve their supercapacitors performance. The PEG was used as a pore-making agent to prepare porous high entropy oxides powder with a large specific surface area of 92.7559 m2 g−1, providing more active sites and ion transport channels. A high specific capacitance of 204 F g−1 at 0.5 A g−1 and good cycle performance of 60.4 % capacitance retention after 10,000 cycles were obtained. Besides, an asymmetric device with improved energy density of 53 W h kg−1 and the power density of 400.8 W kg−1 were reached via the designed microstructure of the high entropy oxide electrode. [ABSTRACT FROM AUTHOR]

The metal free photocatalysts have more environmentally friendly and low-cost advantages but are challenging to find suitable ones. Using the electronic properties of the edge-passivated graphene nanoribbons (EPGNRs) by manipulating the widths and edges, we demonstrate that 5 EPGNRs consisting of metal free elements, which are screened from 10 graphene nanoribbons passivated by H/N/O/F atoms, can achieve high solar-to-hydrogen efficiency in overall water splitting for hydrogen production. After ensuring the energy and thermodynamic stabilities, we construct 16 possible photocatalytic schemes for each EPGNR. At the same time, the feasible ones are selected by calculating charge density distributions, vacuum levels, and the potential energy of the band edges. 9 eligible schemes for overall water splitting are determined and the solar-to-hydrogen efficiencies are calculated according to the overpotentials and band gaps. The highest value of 34.19% is attributed to the H-GNR-O nanoribbon and a larger 38.71% can be boosted by stain engineering, which reveals that the passivated atoms can substantially manipulate the electronic properties and photocatalytic performance of graphene nanoribbons. The calculated Gibbs free energies confirm that the photocatalytic hydrogen and oxygen generations can be driven by the present EPGNRs. Therefore, the newfound metal free EPGNRs are promising for driving overall water splitting for generating hydrogen in a clean way. [Display omitted] • Photocatalytic water splitting schemes are built for five considered nanoribbons. • The highest solar-to-hydrogen efficiency of these schemes can reach 34.19%. • Anisotropic vacuum levels are responsible for the high solar-to-hydrogen efficiency. • Thermodynamic feasibility of the built schemes is ensured by the Gibbs free energies. [ABSTRACT FROM AUTHOR]

Treatment modalities of ependymoma in infants remain controversial. Postoperative adjuvant radiotherapy could prolong overall survival but has the potential to affect nervous system development in infants. The role of adjuvant chemotherapy in prolonging overall survival for infants with ependymoma is still unclear. Therefore we designed this study to explore the effect of treatment modalities on survival time of infants with ependymoma. We studied 72 infants with ependymoma from the Surveillance, Epidemiology, and End Results database in this retrospective analysis. Univariate and multivariate Cox proportional hazard models were adopted to determine hazard ratios and compare overall survival. Among 72 infants with ependymoma, 35 were male (48.6%) and 37 were female (51.4%). The 5-year overall survival of all patients was 67%. Forty-six infants (63.9%) received gross total resection, 20 (27.8%) received subtotal resection, and 6 (8.3%) did not receive surgical resection or only autopsy. Twenty-one infants (29.2%) received radiotherapy, and 45 (62.5%) received chemotherapy. Multivariate analysis revealed that patients accepted surgical resection (No vs. gross total resection, P < 0.001; No vs. subtotal resection, P = 0.026) and chemotherapy (No vs. Yes, P = 0.024) are the independent prognostic factors for overall survival. Treatment modality is associated with survival time in infants with ependymoma. The extent of resection and chemotherapy were independent prognostic factors for infants with ependymoma. [ABSTRACT FROM AUTHOR]

Suicide hotlines are widely used, with potential for identification of callers at especially high risk. This prospective study was conducted at the largest psychological support hotline in China. From 2015 to 2017, all distressed callers were consecutively included and assessed, using a standardized scale consisting of 12 elements, yielding scores of high risk (8–16), moderate risk (4–7), and low risk (0–3) for suicidal act. All high-risk and half of moderate- and low-risk callers were scheduled for a 12-month follow-up. Main outcomes were suicidal acts (nonlethal attempt, death) over follow-up. Of 21,346 fully assessed callers, 5822, 11,791, and 3733 were classified as high-, moderate-, or low-risk for suicidal acts, with 8869 callers (4076 high-, 3258 moderate-, and 1535 low-risk) followed up over 12 months. Over follow-up, 802 (9.0 %) callers attempted suicide or died by suicide. The high-risk callers (15.1 %) had 3-fold higher risk for subsequent suicidal acts than moderate- (5.1 %) and 12-fold higher risk than low-risk callers (1.3 %). The weighted sensitivity, specificity, and positive predictive value of high risk scores were 56.4 %, 74.9 %, and 14.4 %. Assessed callers with different risk levels were followed disproportionally. Suicidal risk assessment during a hotline call is both feasible and predictive of risk, guiding resource allocation to higher risk callers. • A comprehensive suicidal risk assessment scale for suicide prevention hotline has been developed. • Of 21,346 fully assessed hotline callers, 8869 callers were followed up over 12-month. • Findings of this prospective study indicate that predictive validities of the scale are acceptable. • Suicidal risk assessment is viable for determination of intervention plan in hotline in resources-limited countries. [ABSTRACT FROM AUTHOR]