ABSTRACT
Lithium metal anode attracts great attention because of its high specific capacity and low redox potential. However, the uncontrolled dendrite growth and its infinite volume expansion during cycling are extremely detrimental to the practical application. The formation of a solid electrolyte interphase (SEI) plays a decisive role in the behavior of lithium deposition/dissolution during electrochemical processing. Clarifying the essential relationship between SEI and battery performance is a priority. Research in SEI is accelerated in recent years by the use of advanced simulation tools and characterization techniques. The chemical composition and micromorphology of SEIs with various electrolytes are analyzed to clarify the effects of SEI on the Coulombic efficiency and cycle life. In this review, the recent research progress focused on the composition and structure of SEI is summarized, and various advanced characterization techniques applied to the investigation of SEI are discussed. The comparisons of the representative experimental results and theoretical models of SEI in lithium metal batteries (LMBs) are exhibited, and the underneath mechanisms of interaction between SEI and the electrochemical properties of the cell are highlighted. This work offers new insights into the development of safe LMBs with higher energy density.
ABSTRACT
Reversibly light and pH dual-responsive spiropyran-based cellulose nanocrystals (SP-CNCs) is synthesized by the attachment of carboxyl-containing spiropyran (SP-COOH) onto cellulose nanocrystals (CNCs). The resulting structure and properties of SP-CNCs are examined by Fourier transform infrared spectroscopy (FT-IR), elemental analysis, transmission electron microscopy (TEM), atomic force microscopy (AFM), dynamic laser light scattering (DSL), ζ-potential measurements and ultraviolet-visible (UV-Vis) light absorption spectroscopy. SP-CNCs exhibit excellent photochromic and photoswitching properties. Spiropyran moieties on SP-CNCs can be switched between open-ring merocyanine (MC) and closed ring spiropyran (SP) forms under UV/Vis irradiation, leading to color changes. Moreover, SP-CNCs display improved photoresponsiveness, photoreversibility, fatigue resistance, and stability in DMSO than in H2O. We further investigate the pH-responsive behavior of SP-CNCs in H2O. SP-CNCs aqueous solution display different colors at different pH values, which can be directly observed by naked eye, indicating that SP-CNCs can function as a visual pH sensor. These results suggest that light and pH dual-responsive SP-CNCs possess great potential for applications in reversible data storage, sensing, optical switching and light-controlled nanomaterials.
ABSTRACT
Objective: The aim of this study was to perform a quantitative analysis to evaluate the efficacy of cognitive behavioral therapy (CBT) on mood disorders, sleep, fatigue, and its impact on quality of life (QOL) in Parkinson's Disease (PD). Methods: We searched for randomized controlled trials in three electronic databases. Fourteen studies, including 507 patients with PD, met the inclusion criteria. We determined the pooled efficacy by standard mean differences and 95% confidence intervals, using I 2 to reveal heterogeneity. Results: The result showed CBT had a significant effect on depression [-0.93 (95%CI, -1.19 to -0.67, P < 0.001)] and anxiety [-0.76 (95%CI, -0.97 to -0.55, P < 0.001)]. Moderate effect sizes were noted with sleep disorders [-0.45 (95% CI, -0.70 to -0.20, P = 0.0004)]. There was no evident impact of CBT on fatigue or QOL. We found an intervention period >8 weeks was advantageous compared with <8 weeks, and CBT implemented in non-group was more effective than in group. Between the delivery methods, no significant difference was found. Conclusion: We found that CBT in patients with PD was an efficacious therapy for some non-motor symptoms in PD, but not efficacious for fatigue and QOL. These results suggest that CBT results in significant improvement in PD and should be used as a conventional clinical intervention.
ABSTRACT
The gut-brain axis has received considerable attention in recent years, and the "psychobiotics" concept indicates that probiotics have a potential positive effect on cognitive function. Therefore, the aim of this study was to quantitatively evaluate the influence of probiotics on cognition. We conducted a random-eï¬ ;ects meta-analysis of 7 controlled clinical trials and 11 animals studies to evaluate the eï¬ ;ects of probiotics on cognitive function. Probiotics supplementation enhanced cognitive function in both human (0.24 [0.05-0.42]; I2 = 0 %) and animal studies (0.90 [0.47-1.34]; I2 = 74 %). Subgroup analyses indicated that the effects of probiotics on cognitively impaired individuals (0.25 [0.05-0.45]; I2 = 0 %) were greater than those on healthy ones (0.15 [-0.30 to 0.60]; I2 = 0 %). Furthermore, compared with a multiple-probiotic supplement, a single strain of probiotics was more effective in humans. The meta-analysis provided some suggestions for probiotics intervention and tended to support a customized approach for different individuals to ameliorate cognitive disorders. Future additional clinical trials are necessary to evaluate therapeutic effect and influencing factors.
