Summary
A nitrogen‐doped carbon coated subglobose Na3V2(PO4)2F3@C (NVPF) cathode for sodium‐ion batteries was synthesized by using hexadecyl trimethyl ammonium bromide (CTAB) as soft template and ...polyvinylidene fluoride (PVDF) as carbon source. CTAB plays a significant role on the formation of sphere micelles. Precursor ions are self‐assembled on the surface at appropriate concentration and its mechanism is investigated in subglobose NVPF@C‐4. CTAB also increases the conductivity of carbon layer as −(CH3)3N+ in CTAB is combined with residual carbon from PVDF to form partially N‐doped carbon. Meanwhile, the carbon source PVDF contributes to prevent the generation of impurity Na3V2(PO4)3 by compensating the evaporative fluorine. Generally, CTAB and PVDF play multifunctional roles in regulating Na3V2(PO4)2F3@C cathode with well‐developed crystallite, high rate performance, good conductivity, and ultra‐long cycle life. The specific capacity of NVPF@C‐4 cathode at 0.1 C and 10 C is as high as 121.5 mAh·g−1 and 99.2 mAh·g−1 with high capacity retention of 90.1% even after 1000 cycles at 10 C. The excellent rate performance is also attributed to the high diffusion coefficient of Na+ and high exchange current according to the kinetic analysis. The enhanced electrochemical performances reveal the special regulation in this paper is feasible to obtain excellent structural stability of NVPF materials.
Spherical micelles are formed through the regular arrangement of hydrophobic long carbon chain (C16H33−) and hydrophilic trimethylamine (−(CH3)3N+) of CTAB. The hydrophobic PVDF are homogeneously dispersed in the aqueous solution under the dispersing role of CTAB. Through the self‐assembled of precursor anions (PO43−, F−) and cations (Na+, V3+) on the surface of micelle, subglobose Na3V2(PO4)3F3 cathode for sodium‐ion batteries with well‐developed crystallite, ultra‐long cycle life and high rate performance are constructed after the sintering process.
Whether BDNF protein and BDNF mRNA expression of the medial prefrontal cortex (mPFC; cingulated cortex area 1 (Cg1), prelimbic cortex (PrL), and infralimbic cortex (IL)), amygdala, and hippocampus ...(CA1, CA2, CA3, and dentate gyrus (DG)) was involved in fear of posttraumatic stress disorder (PTSD) during the situational reminder of traumatic memory remains uncertain. Footshock rats experienced an inescapable footshock (3 mA, 10 s), and later we have measured fear behavior for 2 min in the footshock environment on the situational reminder phase. In the final retrieval of situational reminder, BDNF protein and mRNA levels were measured. The results showed that higher BDNF expression occurred in the Cg1, PrL, and amygdala. Lower BDNF expression occurred in the IL, CA1, CA2, CA3, and DG. BDNF mRNA levels were higher in the mPFC and amygdala but lower in the hippocampus. The neural connection analysis showed that BDNF protein and BDNF mRNA exhibited weak connections among the mPFC, amygdala, and hippocampus during situational reminders. The present data did not support the previous viewpoint in neuroimaging research that the mPFC and hippocampus revealed hypoactivity and the amygdala exhibited hyperactivity for PTSD symptoms. These findings should be discussed with the previous evidence and provide clinical implications for PTSD.
Posttraumatic stress disorder (PTSD) is a complex syndrome that may occur after life-threatening events. Fear memory abnormalities may play vital roles in the pathogenesis of PTSD. Previous work has ...found that fear memories are not rigid; the retrieval of fear memories may change over time. Furthermore, prior studies suggest that theta wave (4 Hz) activity is highly correlated with fear expression in an animal model. However, the relationship between pathological fear memory and potential brain wave features in PTSD remains largely uncharacterized. Here, we hypothesized that after traumatic stress exposure, the longitudinal dynamics of abnormal fears in PTSD animal models could be reflected by the measurement of local field potentials (LFPs). Using a well-established modified single-prolonged stress and footshock (SPS & FS) PTSD rat model, animals were restrained for 2 h and subsequently subjected to 20 min of forced swimming, then exposed to diethyl ether until they lost consciousness and placed in a conditioning chamber for fear conditioning. To characterize the temporal changes, we characterized freezing behavior brain wave features during the conditioning chamber re-exposure in the early (10 and 30 min; 2, 4, and 6 h) and late (day 1, 3, 7, and 14) phases after traumatic stress exposure. Our results indicate that SPS & FS rats showed co-morbid PTSD phenotypes including significantly higher levels of anxiety-, depression-, and anhedonia-like behaviors, and impaired fear extinction. Delta wave (0.5–4 Hz) suppression in the medial prefrontal cortex, amygdala, and ventral hippocampus occurred 10 and 30 min after traumatic stress, followed by continuous delta wave activity from 2 h to day 14, correlating with fear levels. tDCS reduced delta activity and alleviated PTSD-like phenotypes in the SPS & FS group. In this study, profiling abnormal fears with brain wave correlates may improve our understanding of time-dependent pathological fear memory retrieval in PTSD and facilitate the development of effective intervention strategies.
•The longitudinal dynamics of abnormal fears in PTSD animal models can be reflected by local field potential measurements.•The early and late time phases were observed after traumatic stress exposure.•The state of PTSD modeling could be differentiated from the modeling of learned fears.•The phenotypes of PTSD modeling could be alleviated by non-invasive transcranial direct current modulation.•The longitudinal dynamics of abnormal fears in PTSD animal models can be reflected by local field potential measurements.•The early and late time phases were observed after traumatic stress exposure.•The state of PTSD modeling could be differentiated from the modeling of learned fears.
Posttraumatic stress disorder (PTSD) is a complex disorder that involves physiological, emotional, and cognitive dysregulation that may occur after exposure to a life-threatening event. In contrast ...with the condition of learned fear with resilience to extinction, abnormal fear with impaired fear extinction and exaggeration are considered crucial factors for the pathological development of PTSD. The prefrontal cortex (mPFC) is considered a critical region of top-down control in fear regulation, which involves the modulation of fear expression and extinction. The pathological course of PTSD is usually chronic and persistent; a number of studies have indicated temporal progression in gene expression and phenotypes may be involved in PTSD pathology. In the current study, we use a well-established modified single-prolonged stress (SPS&FS) rat model to feature PTSD-like phenotypes and compared it with a footshock fear conditioning model (FS model); we collected the frontal tissue after extreme stress exposure or fear conditioning and extracted RNA for transcriptome-level gene sequencing. We compared the genetic profiling of the mPFC at early (<2 h after solely FS or SPS&FS exposure) and late (7 days after solely FS or SPS&FS exposure) stages in these two models. First, we identified temporal differences in the expressional patterns between these two models and found pathways such as protein synthesis factor eukaryotic initiation factor 2 (EIF2), transcription factor NF-E2-related factor 2 (NRF2)-mediated oxidative stress response, and acute phase responding signaling enriched in the early stage in both models with significant p-values. Furthermore, in the late stage, the sirtuin signaling pathway was enriched in both models; other pathways such as STAT3, cAMP, lipid metabolism, Gα signaling, and increased fear were especially enriched in the late stage of the SPS&FS model. However, pathways such as VDR/RXR, GP6, and PPAR signaling were activated significantly in the FS model's late stage. Last, the network analysis revealed the temporal dynamics of psychological disorder, the endocrine system, and also genes related to increased fear in the two models. This study could help elucidate the genetic temporal alteration and stage-specific pathways in these two models, as well as a better understanding of the transcriptome-level differences between them.
•Stage-specific pathways identified in rat models of conditioned fear and PTSD-like traits.•The findings elucidate the genetic temporal alteration in the prefrontal area linked to top-down fear control.•The study reveals genetic temporal changes at the transcriptome level and differences between the two models.
Objective
To investigate the relationship between sleep problems and development in preschool children with suspected developmental delay.
Methods
A total of 192 preschool children (mean age 4 years; ...131 males, 61 females) were recruited from the Child Development Clinic, including 98 preterm children and 94 age- and sex-matched full-term children. All participants underwent evaluation of gross motor, fine motor and speech performance. All parents of all participants completed the Children's Sleep Habits Questionnaire (CSHQ). Some of the participants also underwent psychological evaluation. Correlation analysis and community network analysis were used to investigate the interactions.
Results
The developmental status was: 75.5% developmental delay, 19.3% borderline development, and 5.2% normal development. Eighty-nine percent of the subjects had abnormal CSHQ scores. Age, gestational age, speech development, cognitive development, and socio-emotional development were significantly correlated with the CSHQ. Significant interactions between sleep problems and development were noted mostly in the preterm group.
Conclusion
High prevalence of sleep disturbances in children at the Child Development Center was noted and associated with multiple factors. Therefore, during the multidisciplinary evaluation of children with possible developmental delay, inquiring about their sleep quality and habits is strongly recommended. Mitigating sleep problems enhances the efficacy of early intervention programs.
●LiMn0.8Fe0.2PO4/C nanocrystal is synthesized by a facile solvothermal reaction.●Melamine is used as a nitrogen source of N-doped carbon coated LiMn0.8Fe0.2PO4/C.●The transformation law of morphology ...from nanosheet to nanoparticle is studied.●The positive effect of N atoms on the electrochemical performance is illustrated.●Particle-like LMFP-7 delivers excellent cycling performance and chemical stability.
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N-doped carbon coated LiMn0.8Fe0.2PO4 nanocrystal for lithium-ion batteries was prepared by a facile solvothermal method. The doping effect of nitrogen is regulated by altering the addition amount of nitrogen source melamine. Result shows that the introduction of N atoms does not change the crystal structure of LiMn0.8Fe0.2PO4/C. The ‒NH2 functional groups in melamine can react with the ‒OH groups in pyrolytic carbon generated by the pre-sintering of sucrose. Then, multiple nanosheets in LMFP-0 are combined together and the morphology of LiMn0.8Fe0.2PO4/C is transformed to nano particle-like in LMFP-7. The doped nitrogen in the forms of pyridinic, pyrrolic and graphitic N are derived from the combination of pyrolytic carbon and melamine, which can generate active defective sites and improve the electronic conductivity and diffusion rate of lithium ions. Sample LMFP-7 delivers the best electrochemical performance with a capacity of 154.7, 144.2 and 110.0 mA h g−1 at 0.1, 1 and 5 C, respectively. The LiMn0.8Fe0.2PO4/C cathode exhibits good electrochemical reversibility, low charge transfer resistance (46.9 Ω) and high diffusion coefficient (1.35 × 10−13 cm2 s−1). It also delivers excellent cyclic performance, structural stability and chemical stability.
Poly(vinyl alcohol), whose pyrolysis carbon possesses high conductivity of 8.88 × 10−1 S/cm, was used to synthesize xLiFePO4/C·(1 − x)Li3V2(PO4)3/C cathode. It was characterized by X‐ray diffraction, ...scanning electron microscopy, conductivity, cyclic voltammetry, and galvanostatic charge and discharge experiments. Results show that LiFePO4/C and Li3V2(PO4)3/C coexists in the cathode. The particles sizes of 0.75LiFePO4/C·0.25Li3V2(PO4)3/C (x = 0.75) are much smaller than 100 nm due to the role of poly(vinyl alcohol). Its conductivity is 8.79 × 10−2 S/cm. The oxidative and reductive peaks in cyclic voltammetry are sharp and symmetrical. Their low potential gaps indicate that the extractions and insertions of lithium ion possess excellent reversibility. Its discharge capacities at 1 and 5 C are 141.1 and 100.1 mAh/g. The more Li3V2(PO4)3/C in cathode results in the deterioration of electrochemical performances due to its low theoretical capacity. It is concluded that poly(vinyl alcohol) is an effective carbon source in the preparation of xLiFePO4/C·(1 − x)Li3V2(PO4)3/C composite cathode with excellent performances.
LiMn0·8Fe0·2PO4/C nanocrystal was synthesized by a facile solvothermal reaction. The pH and concentration of lithium ion are changing with the increase of LiOH. The deposition law of precursor ions ...is investigated, in which Li+ exceeds the necessary stoichiometric ratio even in the lowest amount of LiOH. Mn2+ and Fe2+ possess the similar fixation tendency, and 87.88% Mn2+ are deposited at the pH of 3.30. However, nearly all Fe2+ are precipitated in a wide pH range (2.96–3.85). The morphology changes from nanosheet to nanoellipsoid under the cooperation of pH and precursor ions. The components of LiMnPO4 and LiFePO4 in LiMn0·8Fe0·2PO4/C are predicted and their contributions to capacity are close to the actual results. Sample S-2.6 delivers the optimum electrochemical performance with a capacity of 150.9, 134.6 and 107.5 mA h·g−1 at 0.05, 1 and 5 C, respectively. It also exhibits high reversibility, low charge transfer resistance (41.2 Ω) and excellent diffusion coefficient (5.38 × 10−11 cm2·s−1). The capacity retention of sample S-2.6 reaches 96.03% after 200 cycles and it maintains original structure without obvious change according to the ex-situ XRD results. The morphology of the cycled cathode film also maintains its integrity without evident cracks. The low dissolution of Mn2+ and Fe2+ from LiMn0·8Fe0·2PO4/C shows the enhanced chemical stability.
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•LiMn0·8Fe0·2PO4/C nanocrystal is synthesized by a facile solvothermal reaction.•The deposition law of precursor ions under the driving of pH is researched.•The transformation law of morphology from nanosheet to nanoellipsoid is studied.•The component of LiMnPO4 and LiFePO4 and contribution to capacity are predicted.•Nanoellipsoid S-2.6 delivers excellent cycling performance and chemical stability.
•High performance N-doped Na3V2(PO4)2F3/C is constructed by a PECVD technology.•Pyridinic, pyrrolic and graphitic nitrogen are generated at high energy condition.•The formation of defects on the ...carbon can accelerate the diffusion of sodium ions.•NVPF@N-3 delivers excellent rate, cyclic performance and structural stability.•The capacity retention of cathode NVPF@N-3 is 91.4% at 10 c after 1000 cycles.
One N-doped carbon coated Na3V2(PO4)2F3/C cathode for sodium-ion batteries was successfully prepared by a Plasma enhanced chemical vapor deposition (PECVD) method. N2 gas is used as the nitrogen source and it is ionized to form chemically active nitrogen ion. It can easily react with the carbon atoms in sample Na3V2(PO4)2F3/C. Research results show that the introduction of N does not affect the crystal structure of the material. The N-doped carbon layer in sample Na3V2(PO4)2F3/C becomes more and more homogeneous. The formation of the pyridinic nitrogen, pyrrolic nitrogen and graphitic nitrogen in the carbon layer can generate additional active sites to shorten the transmission distance of sodium ions, which can improve the electrochemical performance of Na3V2(PO4)2F3/C cathode. The NVPF@N-3 cathode treated by PECVD for 30 min displays excellent rate performance (109.8 mAh•g−1 at 5 C) and cyclic performance, in which the capacity retention after 1000 cycles at 10 C is 91.4% and the crystal structure of NVPF@N-3 is well maintained. This research demonstrates that the pyrolytic carbon in Na3V2(PO4)2F3/C cathode for sodium-ion batteries can be effectively doped by Nitrogen through a novel PECVD technology.
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The rhizome of Davallia formosana is commonly used to treat bone disease including bone fracture, arthritis, and osteoporosis in Chinese herbal medicine. Here, we report the effects of WL1101, the ...ethanol extracts of fresh rhizomes of Davallia formosana on ovariectomy-induced osteoporosis. In addition, excess activated bone-resorbing osteoclasts play crucial roles in inflammation-induced bone loss diseases, including rheumatoid arthritis and osteoporosis. In this study, we examined the effects of WL1101 on receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis. Treatment with WL1101 significantly inhibited RANKL-stimulated osteoclastogenesis. Two isolated active compounds, ((−)-epicatechin) or WL14 (4-hydroxy-3-aminobenzoic acid) could also inhibit RANKL-induced osteoclastogenesis. WL1101 suppressed the RANKL-induced nuclear factor-κB (NF-κB) activation and nuclear translocation, which is the key process during osteoclastogenesis, by inhibiting the activation of IκB kinase (IKK) and IκBα. In animal model, oral administration of WL1101 (50 or 200 mg/kg/day) effectively decreased the excess bone resorption and significantly antagonized the trabecular bone loss in ovariectomized rats. Our results demonstrate that the ethanol extracts of fresh rhizomes of Davallia formosana inhibit osteoclast differentiation via the inhibition of NF-κB activation and effectively ameliorate ovariectomy-induced osteoporosis. WL1101 may thus have therapeutic potential for the treatment of diseases associated with excessive osteoclastic activity.
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