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1.
Proc Natl Acad Sci U S A ; 121(33): e2401109121, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39116136

RESUMO

Na5YSi4O12 (NYSO) is demonstrated as a promising electrolyte with high ionic conductivity and low activation energy for practical use in solid Na-ion batteries. Solid-state NMR was employed to identify the six types of coordination of Na+ ions and migration pathway, which is vital to master working mechanism and enhance performance. The assignment of each sodium site is clearly determined from high-quality 23Na NMR spectra by the aid of Density Functional Theory calculation. Well-resolved 23Na exchangespectroscopy and electrochemical tracer exchange spectra provide the first experimental evidence to show the existence of ionic exchange between sodium at Na5 and Na6 sites, revealing that Na transport route is possibly along three-dimensional chain of open channel-Na4-open channel. Variable-temperature NMR relaxometry is developed to evaluate Na jump rates and self-diffusion coefficient to probe the sodium-ion dynamics in NYSO. Furthermore, NYSO works well as a dual ion conductor in Na and Li metal batteries with Na3V2(PO4)3 and LiFePO4 as cathodes, respectively.

2.
Fa Yi Xue Za Zhi ; 40(2): 154-163, 2024 Apr 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38847030

RESUMO

OBJECTIVES: To develop a deep learning model for automated age estimation based on 3D CT reconstructed images of Han population in western China, and evaluate its feasibility and reliability. METHODS: The retrospective pelvic CT imaging data of 1 200 samples (600 males and 600 females) aged 20.0 to 80.0 years in western China were collected and reconstructed into 3D virtual bone models. The images of the ischial tuberosity feature region were extracted to create sex-specific and left/right site-specific sample libraries. Using the ResNet34 model, 500 samples of different sexes were randomly selected as training and verification set, the remaining samples were used as testing set. Initialization and transfer learning were used to train images that distinguish sex and left/right site. Mean absolute error (MAE) and root mean square error (RMSE) were used as primary indicators to evaluate the model. RESULTS: Prediction results varied between sexes, with bilateral models outperformed left/right unilateral ones, and transfer learning models showed superior performance over initial models. In the prediction results of bilateral transfer learning models, the male MAE was 7.74 years and RMSE was 9.73 years, the female MAE was 6.27 years and RMSE was 7.82 years, and the mixed sexes MAE was 6.64 years and RMSE was 8.43 years. CONCLUSIONS: The skeletal age estimation model, utilizing ischial tuberosity images of Han population in western China and employing the ResNet34 combined with transfer learning, can effectively estimate adult ischium age.


Assuntos
Determinação da Idade pelo Esqueleto , Aprendizado Profundo , Imageamento Tridimensional , Ísquio , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Ísquio/diagnóstico por imagem , Adulto , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Imageamento Tridimensional/métodos , China , Estudos Retrospectivos , Determinação da Idade pelo Esqueleto/métodos , Idoso , Adulto Jovem , Idoso de 80 Anos ou mais , Reprodutibilidade dos Testes
3.
Fa Yi Xue Za Zhi ; 40(3): 245-253, 2024 Jun 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-39166305

RESUMO

OBJECTIVES: To describe the current state of research and future research hotspots through a metrological analysis of the literature in the field of forensic anthropological remains identification research. METHODS: The data retrieved and extracted from the Web of Science Core Collection (WoSCC), the core database of the Web of Science information service platform (hereinafter referred to as "WoS"), was used to analyze the trends and topic changes in research on forensic identification of human remains from 1991 to 2022. Network visualisation of publication trends, countries (regions), institutions, authors and topics related to the identification of remains in forensic anthropology was analysed using python 3.9.2 and Gephi 0.10. RESULTS: A total of 873 papers written in English in the field of forensic anthropological remains identification research were obtained. The journal with the largest number of publications was Forensic Science International (164 articles). The country (region) with the largest number of published papers was China (90 articles). Katholieke Univ Leuven (Netherlands, 21 articles) was the institution with the largest number of publications. Topic analysis revealed that the focus of forensic anthropological remains identification research was sex estimation and age estimation, and the most commonly studied remains were teeth. CONCLUSIONS: The volume of publications in the field of forensic anthropological remains identification research has a distinct phasing. However, the scope of both international and domestic collaborations remains limited. Traditionally, human remains identification has primarily relied on key areas such as the pelvis, skull, and teeth. Looking ahead, future research will likely focus on the more accurate and efficient identification of multiple skeletal remains through the use of machine learning and deep learning techniques.


Assuntos
Bibliometria , Restos Mortais , Antropologia Forense , Humanos , Antropologia Forense/métodos , Publicações/estatística & dados numéricos
4.
Angew Chem Int Ed Engl ; : e202411059, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39011573

RESUMO

Anionic redox chemistry can surpass theoretical limits of conventional layered oxide cathodes in energy density. A recent model system of sodium-ion batteries, O3-NaLi1/3Mn2/3O2, demonstrated full anionic redox capacity but is limited in reversibility and kinetics due to irreversible structural rearrangement and oxygen loss. Solutions to these issues are missing due to the challenging synthesis. Here, we harness the unique structural richness of sodium layered oxides and realize a controlled ratio of P2 structural intergrowth in this model compound with the overall composition maintained. The resulted O3 with 27% P2 intergrowth structure delivers an excellent initial Coulombic efficiency of 87%, comparable to the state-of-the-art Li-rich NMCs. This improvement is attributed to the effective suppression of irreversible oxygen release and structural changes, evidenced by operando Differential Electrochemical Mass Spectroscopy and X-ray Diffraction. The as-prepared intergrowth material, based on the environmentally benign Mn, exhibits a reversible capacity of 226 mAh g-1 at C/20 rate with excellent cycling stability stemming from the redox reactions of oxygen and manganese. Our work isolates the role of P2 structural intergrowth and thereby introduces a novel strategy to enhance the reversibility and kinetics of anionic redox reactions in sodium layered cathodes without compromising capacity.

5.
Angew Chem Int Ed Engl ; 63(27): e202406750, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38651747

RESUMO

Electrocatalytic reduction of nitrate to ammonia provides a green alternate to the Haber-Bosch method, yet it suffers from sluggish kinetics and a low yield rate. The nitrate reduction follows a tandem reaction of nitrate reduction to nitrite and subsequent nitrite hydrogenation to generate ammonia, and the ammonia Faraday efficiency (FE) is limited by the competitive hydrogen evolution reaction. Herein, we design a heterostructure catalyst to remedy the above issues, which consists of Ni nanosphere core and Ni(OH)2 nanosheet shell (Ni/Ni(OH)2). In situ Raman spectroscopy reveals Ni and Ni(OH)2 are interconvertible according to the applied potential, facilitating the cascade nitrate reduction synergistically. Consequently, it attains superior electrocatalytic nitrate reduction performance with an ammonia FE of 98.50 % and a current density of 0.934 A cm-2 at -0.476 V versus reversible hydrogen electrode, and exhibits an average ammonia yield rate of 84.74 mg h-1 cm-2 during the 102-hour stability test, which is highly superior to the reported catalysts tested under similar conditions. Density functional theory calculations corroborate the synergistic effect of Ni and Ni(OH)2 in the tandem reaction of nitrate reduction. Moreover, the Ni/Ni(OH)2 catalyst also possesses good capability for methanol oxidation and thus is used to establish a system coupling with nitrate reduction.

6.
Foods ; 13(2)2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38254491

RESUMO

In rural areas, the aging of households is becoming increasingly severe, and the issue of dietary imbalance among the elderly is becoming increasingly prominent. Using data from the China Health and Nutrition Survey (CHNS), the negative binomial regression method was used to investigate the impact of household income level on dietary imbalance among rural elderly people, and to explore the heterogeneity of household income structure and its role in the relationship between the two. Research has found that an increase in total household income significantly improves the dietary quality of rural elderly people, and the income structure variable enhances its negative pulling effect on dietary imbalance. For elderly people with moderate dietary imbalance, the effect of increased family income is most significant. In different income groups, the impact of total household income on dietary imbalance in the high-income group is greater than that in the low-income group, and there is also a significant difference in the role played by the proportion of net income from agricultural operations. Therefore, it is necessary to increase the non working income of the elderly, strengthen social responsibility for elderly care, and alleviate the problem of dietary imbalance among rural elderly people.

7.
Front Public Health ; 12: 1329234, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38463162

RESUMO

China's rural residents have basically solved the problem of subsistence, but due to aging, the prevalence of sarcopenia (abbreviated as sarcopenia) has been increasing year by year, especially the skeletal muscle health of the rural older residents has not been sufficiently paid attention to, so analyses of the impact of income level on the skeletal muscle health of the older people in rural areas of China are of great practical significance. Based on the annual data of the China Health and Nutrition Survey (CHNS) in 2006, 2009, and 2011, we introduced the mediator variable of dietary knowledge and used the Probit model regression, mediation effect model, and instrumental variable regression to assess the skeletal muscle health status of the rural older people in China and explore the mechanism of the influence of the income level on the skeletal muscle health of the rural older residents in China. The primary objectives of this study were to evaluate the impact of income level on the skeletal muscle health status of older adults living in rural areas of China and to investigate the underlying mechanisms. By analyzing the findings of this study, our aim is to establish a correlation between the economic status and skeletal muscle health of older adults in rural communities, as well as elucidate the influence of income level and dietary knowledge on their skeletal muscle health. Through the attainment of these objectives, we hope to provide valuable insights and recommendations for enhancing skeletal muscle health among the rural older population in China. Based on our research findings, it can be inferred that there was a significant association between the financial status of rural older adults and their skeletal muscle health. Additionally, the prevalence of sarcopenia was lower among individuals with higher income levels, and there was a negative correlation between the prevalence of sarcopenia and the level of dietary knowledge among rural older individuals. The knowledge of dietary knowledge level of rural older people plays a mediating role in the income level and the prevalence of sarcopenia. Moreover, with the change in income level and the increase in age, the change in skeletal muscle health status showed obvious heterogeneity, in which the effect on the relatively younger (65-70 years old) samples was greater. Therefore, sustained income growth remains an effective way to improve the skeletal muscle health of older rural residents. At the same time, improving dietary knowledge and dietary quality among the older people is important in preventing a decline in muscle strength and physical function and in preventing the onset of sarcopenia.


Assuntos
Sarcopenia , Humanos , Idoso , Sarcopenia/epidemiologia , População Rural , Músculo Esquelético/fisiologia , Dieta , Força Muscular/fisiologia
8.
RSC Adv ; 14(31): 22159-22168, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39005245

RESUMO

Phosphate-based NASICON materials are an excellent candidate for both electrode and solid electrolyte materials in sodium-ion batteries (SIBs). The development of new NASICON materials with higher ionic and electronic conductivities based on low cost and abundant elements is necessary for advancement of SIBs. In this study, we report the structure, morphology and conductivity of the earth-abundant Mn/Fe-based NASICON phosphate Na4MnFe(PO4)3. Pure phase powders were synthesized by solution-assisted solid-state reaction, sol-gel and Pechini methods. From refined X-ray diffraction data, the prepared phosphate was found to crystallize in trigonal symmetry with space group R3̄c. The effect of synthesis method on microstructure and conductivity was investigated using scanning electron microscopy (SEM), atomic force microscopy (AFM) and impedance measurements. Smaller particle size and regular distribution of the powder was designed using a Pechini route. Impedance measurement showed a notable enhancement in conductivity, from 0.543 × 10-7 to 1.52 × 10-7 S cm-1 at 30 °C, when the powder synthesis method was altered from a solution-assisted solid-state reaction to the Pechini route, highlighting the remarkable effect of the synthesis method on conductivity.

9.
Environ Pollut ; 352: 124129, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38729505

RESUMO

Human-imported pollutants could induce water black, changing microbial community structure and function. Employed 16S rRNA high-throughput sequencing, field-scale investigations and laboratory-scale experiments were successively conducted to reveal mechanistic insights into microbial community assembly and succession of black-odor waters (BOWs). In the field-scale investigation, livestock breeding wastewater (56.7 ± 3.2%) was the most critical microbial source. Moreover, fermentation (27.1 ± 4.4%) was found to be the dominant function. Combined with laboratory experiments, the critical environmental factors, such as total organic carbon (30-100 mg/L), ammonia nitrogen (2.5-9 mg/L), initial dissolved oxygen (2-8 mg/L) and chlorophyll a (0-90 mg/L), impacted the intensity of blackening. The differentiation of ecological niches within the microbial community played a significant role in driving the blackening speed. In laboratory-scale experiments, the microbial ecological niche determined the blackening timing and dominations of the stochastic processes in the microbial assembly process (88 - 51%). The three stages, including the anaerobic degradation stage, blackening stage and slow recovery stage, were proposed to understand the assembly of the microbial communities. These findings enhance our understanding of microorganisms in BOWs and provide valuable insights for detecting and managing heavily organic polluted waters.


Assuntos
Microbiota , Águas Residuárias , Águas Residuárias/microbiologia , Águas Residuárias/química , RNA Ribossômico 16S/genética , Bactérias/genética , Bactérias/metabolismo , Poluentes Químicos da Água/análise , Microbiologia da Água
10.
Mater Horiz ; 11(16): 3935-3945, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38868994

RESUMO

O3-type layered oxide cathodes are promising for practical sodium-ion batteries (SIBs) owing to their high theoretical capacity, facile synthesis, and sufficient Na+ storage. However, they face challenges such as rapid capacity loss and poor cycling stability, mainly attributed to irreversible phase transitions. To address these challenges, a novel cathode material, Li/Sn co-substituted O3-Na0.95Li0.07Sn0.01Ni0.22Fe0.2Mn0.5O2 (LSNFM), has been designed by regulating the electronic structure, in which Li+ activates more redox reactions of Ni2+/3+ and Fe3+/4+ above 2.5 V and suppresses the redox reactivity of Mn3+/4+ below 2.5 V, while Sn4+ can prevent the charge delocalization in the transition metal layer, contributing to structural stability. Due to this synergistic effect, the as-prepared LSNFM electrode with high structural reversibility displays a 27.2% capacity increase contributed by the high-voltage transition metal ion redox activity and exhibits excellent long-term cycling stability, an 84.0% capacity retention after 500 cycles at 1 C and an 84.7% capacity retention after 2000 cycles at 5 C. The fundamental mechanism is fully investigated using systematic in situ/ex situ characterization techniques and density functional theory computations. This work provides a paradigm for designing long-term cycle life cathode materials by synergistically regulating the electronic structure in practical SIBs.

11.
Nanoscale ; 16(29): 14108-14115, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39007402

RESUMO

Inorganic CsPbI3 perovskite nanocrystals (NCs) exhibit remarkable optoelectronic properties for illumination. However, their poor stability has hindered the development of light-emitting diodes (LEDs) based on these materials. In this study, we propose a facile method to synthesize Mg2+-doped CsPbI3 NCs with enhanced stability and high photoluminescence (PL) intensity under ambient air conditions. Theoretical calculations confirm that doped NCs possess stronger formation energy compared to undoped NCs. The undoped CsPbI3 NCs emit red light at approximately 653 nm. We optimize the doping ratio to 1/30, which significantly enhances the photoluminescence of single-particle CsPbI3 NCs. Subsequently, we fabricate a red LED by combining the CsPbI3 NCs with a blue chip. The resulting LED, based on the doped CsPbI3 NCs, exhibits excellent performance with a high luminance of 4902.22 cd m-2 and stable color coordinates of (0.7, 0.27). This work not only presents a simple process for synthesizing perovskite NCs but also provides a design strategy for developing novel red LEDs for various applications.

12.
Nat Commun ; 15(1): 1447, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365760

RESUMO

Exploring an active and cost-effective electrocatalyst alternative to carbon-supported platinum nanoparticles for alkaline hydrogen evolution reaction (HER) have remained elusive to date. Here, we report a catalyst based on platinum single atoms (SAs) doped into the hetero-interfaced Ru/RuO2 support (referred to as Pt-Ru/RuO2), which features a low HER overpotential, an excellent stability and a distinctly enhanced cost-based activity compared to commercial Pt/C and Ru/C in 1 M KOH. Advanced physico-chemical characterizations disclose that the sluggish water dissociation is accelerated by RuO2 while Pt SAs and the metallic Ru facilitate the subsequent H* combination. Theoretical calculations correlate with the experimental findings. Furthermore, Pt-Ru/RuO2 only requires 1.90 V to reach 1 A cm-2 and delivers a high price activity in the anion exchange membrane water electrolyzer, outperforming the benchmark Pt/C. This research offers a feasible guidance for developing the noble metal-based catalysts with high performance and low cost toward practical H2 production.

13.
Nat Commun ; 15(1): 1481, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368426

RESUMO

Stable solid electrolytes are essential to high-safety and high-energy-density lithium batteries, especially for applications with high-voltage cathodes. In such conditions, solid electrolytes may experience severe oxidation, decomposition, and deactivation during charging at high voltages, leading to inadequate cycling performance and even cell failure. Here, we address the high-voltage limitation of halide solid electrolytes by introducing local lattice distortion to confine the distribution of Cl-, which effectively curbs kinetics of their oxidation. The confinement is realized by substituting In with multiple elements in Li3InCl6 to give a high-entropy Li2.75Y0.16Er0.16Yb0.16In0.25Zr0.25Cl6. Meanwhile, the lattice distortion promotes longer Li-Cl bonds, facilitating favorable activation of Li+. Our results show that this high-entropy halide electrolyte boosts the cycle stability of all-solid-state battery by 250% improvement over 500 cycles. In particular, the cell provides a higher discharge capacity of 185 mAh g-1 by increasing the charge cut-off voltage to 4.6 V at a small current rate of 0.2 C, which is more challenging to electrolytes|cathode stability. These findings deepen our understanding of high-entropy materials, advancing their use in energy-related applications.

14.
Front Neurol ; 14: 1309209, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38249731

RESUMO

Multinodular and vacuolar neuronal tumor (MVNT) is a rare and benign neuroepithelial tumor. Most reports describe tumors located in the cerebral hemisphere. A literature review found that 15 cases were located in the posterior cranial fossa, but all lacked pathological evidence. In this case, a patient sought medical attention due to insomnia and irritability. Neuroepithelial tumors were found in the imaging, and the patient underwent radiation therapy. Three years later, malignant tumors were found upon imaging examination. After surgical resection and pathological testing, MVNT occurring in the cerebellum was diagnosed. MVNT is rare in the cerebellum, and direct imaging diagnosis becomes difficult after treatment. Therefore, our report of this case helps to further accurate understanding of the imaging, pathological, and molecular genetic changes occurring before and after MVNT treatment, and will improve the accuracy of pre-treatment diagnosis and reduce the likelihood of overtreatment.

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