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Polyethylene oxide (PEO)-based solid electrolytes have been widely studied in all-solid-state lithium (Li) metal batteries due to their favorable interfacial contact with electrodes, facile fabrication, and low cost, but their inferior Li dendrite suppression capability renders low actual areal capacities of Li metal anodes. Here, we develop a high-capacity all-solid-state battery using a metal-organic framework hosted silicon (Si@MOF) anode and a fiber-supported PEO/garnet composite electrolyte. Si nanoparticles are embedded in the micro-sized MOF-derived carbon host, which efficiently accommodates the repeated deformation of Si over cycles while providing sufficient charge transfer pathways. As a result, the Si@MOF anode shows excellent interfacial stability toward the composite polymer electrolyte for over 1000 h and achieves a high reversible areal capacity of 3 mAh cm-2. The full cell using the LiFePO4 (LFP) cathode is able to deliver 135 mAh g-1 initially and maintains 73.1% of the capacity after 500 cycles at 0.5 C and 60 °C. More remarkably, the full cells with high LFP loadings achieve areal capacities of more than 2 mAh cm-2, exceeding most PEO-based ASSBs using metallic Li. Finally, the pouch cell using the proposed design exhibits decent electrochemical performance and high safety.
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Zinc metal holds a great potential as an anode material for next-generation aqueous batteries due to its suitable redox potential, high specific capacity, and low cost. However, the uncontrollable dendrite growth and detrimental side reactions with electrolytes hinder the practical application of this type of electrodes. To tackle the issues, an ultrathin (â¼1 µm) sulfonated poly(ether ether ketone) (SPEEK) solid-electrolyte interphase (SEI) is constructed onto the Zn anode surface by a facile spin-coating method. We demonstrate that the polymeric SEI simultaneously blocks the water molecules and anions, uniformizes the ion flux, and facilitates the desolvation process of Zn2+ ions, thus effectively suppressing the side reactions and Zn dendrite formation. As a result, the newly developed Zn@SPEEK anode enables a symmetric cell to stably operate over 1000 cycles at 5 mA cm-2 without degradation. Moreover, with the Zn anode paired with a MnO2 cathode, the full cell exhibits an improved Coulombic efficiency (over 99% at 0.1 A g-1), a superior rate capability (127 mA h g-1 at 2 A g-1), and excellent cycling stability (capacity retention of 70% over 1000 cycles at 1 A g-1). This work provides a facile yet effective strategy to address the critical challenges in Zn anodes, paving the way for the development of high-performance rechargeable aqueous batteries.
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Black inorganic materials with low infrared absorption/emission (or IR white) are rare in nature but highly desired in numerous areas, such as solar-thermal energy harvesting, multispectral camouflage, thermal insulation, and anti-counterfeiting. Due to the lack of spectral selectivity in intrinsic materials, such counter-intuitive properties are generally realized by constructing complicated subwavelength metamaterials with costly nanofabrication techniques. Here, the intrinsically low mid-IR emissivity (down to 10%) of the 2D Ti3 C2 Tx MXene is reported. Associated with a high solar absorptance (up to 90%), it embraces the best spectral selectivity among the reported intrinsic black solar-absorbing materials. Its appealing potential in several of the aforementioned areas is experimentally demonstrated. First-principles calculations reveal that the IR emissivity of MXene relies on both the nanoflake orientations and terminal groups, indicating great tunability. The calculations also suggest more potential low-emissivity MXenes including Ti2 CTx , Nb2 CTx , and V2 CTx . This work opens the avenue to further exploration of a family of intrinsically low-emissivity materials with over 70 members.
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This study aimed to identify symptom clusters of chronic obstructive pulmonary disease (COPD) and to examine the relationship between symptom clusters and health-related quality of life (HRQoL). It included 154 hospitalized patients with COPD. The majority of the participants (88.6%) were aged 60 years and above, and the numbers of men and women were approximately equal (men: 55.2%). The Charlson Comorbidity Index (CCI), the Memorial Symptom Assessment Scale (MSAS), and the Chinese version of the Clinical COPD Questionnaire (CCQ) were used to evaluate comorbidity, participant's symptoms, and HRQoL, respectively. Five symptom clusters were identified using exploratory factor analysis, and symptom clusters, especially the Psychological, Pain and Fatigue, GI, and Dyspnea-Sweat symptom clusters, had negative effects on HRQoL in patients with COPD. Understanding the patterns and occurrences of symptom clusters could be essential for developing effective interventions to manage COPD symptoms and improve the patients' HRQoL.
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Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Calidad de Vida/psicología , Síndrome , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría/instrumentación , Psicometría/métodos , Enfermedad Pulmonar Obstructiva Crónica/psicología , Encuestas y CuestionariosRESUMEN
Composite solid electrolytes (CSEs) are regarded as one of the most promising candidates for all-solid-state lithium metal batteries (ASSLMBs) due to inherited desirable features from both ceramic and polymer materials. However, poor interfacial contact/compatibility between the electrodes and solid electrolytes remains a critical challenge. In this work, we prepare a flexible CSE composed of polyoxyethylene (PEO)-perovskite composite with a layer of PEO on either side. This PEO|PEO-perovskite|PEO structure prevents direct contact between the perovskite and lithium metal at the anode side, avoiding the undesired reaction between the two materials (Ti4+ + Li â Ti3+ + Li+). Moreover, the design incorporating the PEO surface on either side enables superb contact between the electrolyte and the electrodes and buffers the change in electrolyte volume from the cathode and lithium metal during repeated cycling, resulting in low interfacial resistances and excellent cycling stability. Meanwhile, perovskite inorganic electrolyte Li0.33La0.557TiO3 (LLTO) 3D nanofiber networks formed by electrospinning enable the CSE to achieve enhanced mechanical strength and high ionic conductivity of 0.16 mS cm-1 at 24 °C. As a result, a Li|PEO-LiTFSI-LLTO|Li symmetric cell remains stable after 400 h of operation without short-circuiting. Most notably, a Li|PEO-LiTFSI-LLTO|LiFePO4 full battery is capable of delivering a high capacity of 135.0 mAh g-1 even at 2 C with a retention rate of 79.0% after 300 cycles at 60 °C. These results demonstrate that the integrated sandwich structure proposed in this work is effective in developing high-performance composite solid electrolytes for ASSLMBs.
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PURPOSE: To evaluate the associations between BADL/IADL disability and depressive symptoms from the perspective of gender among older adults in China. METHODS: This cross-sectional study used the data from the second wave of the China Health and Retirement Longitudinal Study (CHARLS). The sample included 3463 older adults aged 60â¯years and older across China. Multivariable logistic regression models were conducted. RESULTS: Among 3463 older adults, 1240 (35.8%) were classified as depressed, the prevalence of BADL and IADL disabilities were 756 (21.8%) and 1194 (34.5%), respectively. After controlling for covariates, BADL/IADL disability was significantly associated with an increased risk of depression prevalence both in men and women among older adults. Compared with IADL independent, IADL disability was about two times more likely to develop depressive symptoms in men (ORâ¯=â¯2.165, 95% CIâ¯=â¯1.661-2.822), which was much higher than that in women (ORâ¯=â¯1.748, 95% CIâ¯=â¯1.415-2.160). In contrast, the odds of being depressed for women with BADL disability (ORâ¯=â¯1.824, 95% CIâ¯=â¯1.447-2.299) were much higher than the odds for men with BADL disability (ORâ¯=â¯1.791, 95% CIâ¯=â¯1.348-2.379). CONCLUSIONS: Older adults with BADL/IADL disability were more likely to have depressive symptoms both for men and women. However, the associations between depressive symptoms and BADL/IADL disability were different in gender. Our results suggest that differential institutional care service and appropriate strategies for improvement in mental health are required.
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Actividades Cotidianas , Depresión/epidemiología , Anciano , Anciano de 80 o más Años , China/epidemiología , Estudios Transversales , Depresión/etiología , Personas con Discapacidad/psicología , Personas con Discapacidad/estadística & datos numéricos , Femenino , Humanos , Modelos Logísticos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Factores de Riesgo , Factores Sexuales , Encuestas y CuestionariosRESUMEN
This cross-sectional study was conducted to describe the physical activity and sleep in 290 community-dwelling Chinese older adults and to examine the association between physical activity and poor sleep outcomes. Almost half of the samples were poor sleepers. The majority of the samples regularly participated in walking, some household activity, and light sports, yet only a small portion were involved in work-related activity or in strenuous sports. A greater level of overall physical activity (odds ratio = 0.79; 95% confidence interval = [0.73, 0.86]), leisure-time exercise (odds ratio = 0.77; 95% confidence interval = [0.68, 0.85]), and household activity (odds ratio = 0.66; 95% confidence interval = [0.56, 0.78]) were associated with reduced likelihood of being poor sleepers and other poor sleep outcomes, independent of covariates including age, sex, education, family income, the number of children, drinking, and sleep hygiene. Future larger-scale studies that incorporate both objective and subjective measures are needed to further examine the association and to explore the effects of different types of activity on sleep and other well-beings in older adults.
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Ejercicio Físico , Trastornos del Inicio y del Mantenimiento del Sueño , Sueño , Anciano , China , Estudios Transversales , Humanos , CaminataRESUMEN
Daily symptom variability refers to the fluctuation of chronic obstructive pulmonary disease (COPD) symptoms over the day. Although most clinicians can describe the day-to-day variation in symptoms experienced by patients with COPD, little has been done to quantify the variability. This review aims to synthesize evidence of daily symptom variability among patients with stable COPD. Of the 325 potentially relevant articles that were retrieved, 11 observational articles were finally included in the review. Patients with stable COPD commonly experience daily symptom variability, with morning being the most troublesome time of day, followed by night. Morning symptoms had a significant effect on morning routines or daily activities, and night-time symptoms affected the sleep quality of patients. In comparison with patients without symptom variability, patients with morning/night-time symptoms or symptom variability exhibited poorer health status as well as greater disease severity and incidence of exacerbation.
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Actividades Cotidianas , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Calidad de Vida , Estado de Salud , Humanos , Índice de Severidad de la EnfermedadRESUMEN
In this work, a density functional theory (DFT) based first-principles study is carried out to investigate the potential of phosphorene-like SiS and SiSe monolayers as anode materials for sodium-ion (Na-ion) batteries. Results show that both SiS and SiSe have large adsorption energies towards single Na atom of -0.94 and -0.43eV, owing to the charge transfers from Na to SiS or SiSe. In addition, it is found that the highest Na concentration for both SiS and SiSe is x=1 with the chemical formulas of NaSiS and NaSiSe, corresponding to the high theoretical specific capacities for Na storages of 445.6 and 250.4mAhg-1, respectively. Moreover, Na diffusions are very fast and show strong directional behaviors on SiS and SiSe monolayers, with the energy barriers of only 0.135 and 0.158eV, lower than those of conventional anode materials for Na-ion batteries such as Na2Ti3O7 (0.19eV) and Na3Sb (0.21eV). Finally, although SiS and SiSe show semiconducting behaviors, they transform to metallic states after adsorbing Na atoms, indicating enhanced electrical conductivity during battery cycling. Given these advantages, it is expected that both SiS and SiSe monolayers are promising anode materials for Na-ion batteries, and in principle, other Na-based batteries as well.
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OBJECTIVE: To discuss the clinical features, treatment, and prognosis of supratentorial cavernous angiomas in children. METHODS: The clinical data of 25 pediatric patients with supratentorial cavernous angioma, 17 boys and 6 girls, aged 9.6 (1-15), were reviewed retrospectively, and the relationship between the duration of epilepsy before surgery and prognosis was analyzed. RESULTS: The 14 patients with preoperative seizures underwent surgery. All (8/8) of the patients suffering from preoperative seizures with an history of less than one year were seizure free after operation, while only half (3/6) of the patients with an history suffering from preoperative seizures with an history of more than one year were seizure free after operation. Ten of the 11 patients with hemorrhage and hemorrhage-related neurological symptoms as the initial symptoms underwent surgery, and no symptoms of re-bleeding and seizure occurred postoperatively. CONCLUSION: Craniotomy for lesionectomy results in good seizure control and re-bleeding avoidance. Better results with regard to seizure control are associated with shorter duration of symptoms before surgery.