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Biomass-derived porous carbon materials are meaningful to employ as a hard carbon precursor for anode materials of sodium-ion batteries (SIBs) from a sustainability perspective. Here, a straightforward approach is proposed to develop rich closed pores in pinenut-derived carbon, with the aim of improving Na+ plateau storage by adjusting the pyrolysis temperature. The optimized sample, namely the pinenut-derived carbon at 1300 °C, demonstrates remarkable reversible specific capacity of 278 mAh g-1, along with a high initial Coulomb efficiency of 85% and robust cycling stability (with a capacity retention of 89% after 800 cycles at 0.2 A g-1). In situ and ex situ analyses unveil that the developed closed pores play a significant role in enhancing the plateau capacity, providing compelling evidence for the "adsorption-filling" mechanism. Moreover, the corresponding full-cell achieves a high energy density of 245.7 Wh kg-1 (based on the total weight of both electrode active materials) and exhibits outstanding rate capability (191.4 mAh g-1 at 3 A g-1).
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Prior studies have suggested that lower blood pressure increases the mortality risk in the elderly. This study examines the relationship between change in blood pressure and overall mortality in frail elderly patients. Medline, PubMed, Cochrane, and Google Scholar databases were searched until April 2, 2015 using search terms: frail/frailty, elderly/aged, blood pressure, hypertension, cardiovascular events, and mortality/prognosis. Two-arm prospective and retrospective studies that investigated BP and the incidence of mortality in frail elderly patients were included. We found that the chance of mortality decreased with increasing systolic blood pressure (SBP) (pooled HR = 0.870, 95% CI = 0.776-0.976, P = 0.018) and diastolic blood pressure (DBP) (pooled HR = 0.837, 95% CI = 0.77-0.911, P < 0.001). Pulse pressure was not associated with mortality risk (pooled HR = 0.949, 95% CI = 0.897-1.004, P < 0.071). In elderly frailty patients, hypertension has a protective effect in lowering risk of overall mortality. Accurate identification of such elderly population is necessary for optimizing health care.
Assuntos
Doenças Cardiovasculares/mortalidade , Idoso Fragilizado , Hipertensão/epidemiologia , Idoso , Anti-Hipertensivos/uso terapêutico , Doenças Cardiovasculares/terapia , Humanos , Hipertensão/tratamento farmacológico , Incidência , Fatores de RiscoRESUMO
Sodium-ion batteries (SIBs) have been regarded as promising candidates for large-scale energy storage system, and their electrochemical performance is determined by the cathode materials. Recently, the polyanion-type cathode Na4 Fe3 (PO4 )2 P2 O7 (NFPP) demonstrates decent performance, while there exists promotion space with respect to its cycle stability and rate capability. Herein, an entropy-enhanced Na4 Fe2.95 (NiCoMnMgZn)0.01 (PO4 )2 P2 O7 (HE-NFPP) cathode is proposed with improved rate performance (67.1 mAh g-1 at 50 C) and cycle performance (retention of 92.0% after 1000 cycles at 1 C). The enhancement of configuration entropy improves the structural stability of NFPP thermodynamically. In-situ XRD illustrates the sodium storage mechanism of HE-NFPP as an imperfect solid solution reaction driven by Fe2+ /Fe3+ redox with a low volume change of 4.0% (90.9% of NFPP). Through doping, the structure distortion and abrupt rearrangement are inhibited. Additionally, HE-NFPP and hard carbon (HC) are utilized to fabricate pouch cell that demonstrates an average working voltage of 3.0 V and a maximum energy density of 165 Wh kg-1 (based on the total mass of active materials). These results highlight the potential for enhancing the high-rate and long-cycle performance of NFPP as a promising cathode for SIBs through an entropy-enhanced multi-doping strategy.
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Two-photon photodynamic therapy (TP-PDT), as a new method for cancer, has shown unique advantages in tumors. A low two-photon absorption cross-section (δ) in the biologic spectral window and a short triplet state lifetime are the important issues faced by the current photosensitizers (PSs) in TP-PDT. In this paper, the photophysical properties of a series of Ru(II) complexes were studied by density functional theory and time-dependent density functional theory methods. The electronic structure, one- and two-photon absorption properties, type I/II mechanisms, triplet state lifetime, and solvation free energy were calculated. The results showed that the substitution of methoxyls by pyrene groups greatly improved the lifetime of the complex. Furthermore, the addition of acetylenyl groups subtly enhanced δ. Overall, complex 3b possess a large δ(1376 GM), a long lifetime (136 µs), and better solvation free energy. It is hoped that it can provide valuable theoretical guidance for the design and synthesis of efficient two-photon PSs in the experiment.
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Neoplasias , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , FótonsRESUMO
N-Doped amber necklace-like structured MoS2@carbon nanofibers (ANL MoS2@CNFs) were fabricated via the confined growth method, constructing a hierarchical structure with 1D nanofibers, 2D nanosheets, and 3D cross-linked networks. This special structure could effectively alleviate the volume effect and enhance the storage performance of lithium/sodium ion batteries.
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In the present cross-sectional study, based on National Health and Nutrition Examination Survey (NHANES, 2007-2010) cohorts, various risk factors for metabolic syndrome (MetS) and cardiovascular diseases (CVDs) were analyzed (n=12,153). The variables analyzed include, demographics, comorbidities associated with MetS or CVD, behavioral and dietary factors, while the primary endpoints were the prevalence of MetS and CVD. The prevalence of MetS and CVD was slightly higher in males as compared with females (42.50% and 7.65% vs 41.29% and 4.13%, respectively). After controlling for confounding factors, advanced age, family history of diabetes mellitus (DM), overweight, and obesity were significantly associated with the likelihood of MetS, irrespective of gender differences. In males, the diagnosis of prostate cancer and regular smoking were additional risk factors of MetS, whereas, advanced age, family history of heart attack or angina, health insurance coverage, diagnosis of rheumatoid arthritis or depression, obesity and low calorie intake were identified as risk factors for CVD. In addition to the above risk factors, higher physical activity and vitamin D insufficiency were also found to increase the risk of CVD in females. Furthermore, obesity was a higher risk factor for MetS than CVD. Emerging risk factors for CVD identified in this study has major clinical implications. Of interest is the correlation of higher physical activity and the risk of CVD in women and the role of depression and lower calorie intake in general population.
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Doenças Cardiovasculares/epidemiologia , Síndrome Metabólica/epidemiologia , Inquéritos Nutricionais , Comportamento , Estudos Transversais , Demografia , Dieta , Feminino , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Fatores de Risco , Fatores SexuaisRESUMO
An innovative approach for efficient synthesis of petal-like molybdenum disulfide nanosheets inside hollow mesoporous carbon spheres (HMCSs), the yolk-shell structured MoS2@C, has been developed. HMCSs effectively control and confine in situ growth of MoS2 nanosheets and significantly improve the conductivity and structural stability of the hybrid material. The yolk-shell structured MoS2@C is proven to achieve high reversible capacity (993 mA h g-1 at 1 A g-1 after 200 cycles), superior rate capability (595 mA h g-1 at a current density of 10 A g-1), and excellent cycle performance (962 mA h g-1 at 1 A g-1 after 1000 cycles and 624 mA h g-1 at 5 A g-1 after 400 cycles) when evaluated as an anode material for lithium-ion batteries. This superior performance is attributed to the yolk-shell structure with conductive mesoporous carbon as the shell and the stack of two-dimensional MoS2 nanosheets as the yolk.
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Among the numerous candidate materials for lithium ion batteries, ferroferric oxide (Fe3O4) has been extensively concerned as a prospective anode material because of its high theoretical specific capacity, abundant resources, low cost, and nontoxicity. Here, we designed and fabricated a unique yolk-shell construction by generating heterogeneous double-shelled SnO2 and nitrogen-doped carbon on Fe3O4 yolk (denoted as Fe3O4@SnO2@C-N nanoboxes). The yolk-shell structured Fe3O4@SnO2@C-N nanoboxes have the adjustable void space, which permits the free expansion of Fe3O4 yolks without breaking the double shells during the lithiation/delithiation processes, avoiding the structural pulverization. Moreover, the heterogeneous double-shelled SnO2@C-N can meaningfully improve the electronic conductivity and enhance the lithium storage performance. Two metal oxides also show the specific synergistic effect, promoting the electrochemistry reaction. As a result, this yolk-shell structured Fe3O4@SnO2@C-N exhibits high specific capacity (870 mA h g-1 at 0.5 A g-1 after 200 cycles), superior rate capability, and long cycle life (670 mA h g-1 at 3 A g-1 after 600 cycles). This design and construction method can be extended to synthesize other yolk-shell nanostructured anode materials with improved electrochemistry performance.