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1.
J Thorac Dis ; 15(5): 2779-2799, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37324100

RESUMO

Background: Tuberculosis (TB) remains a significant challenge for public health and is closely associated with malnutrition; however, few studies have attempted to screen malnutrition among TB patients. The study aimed to evaluate the nutrition status and build a new nutritional screening model for active TB. Methods: A retrospective, multicenter, large cross-sectional study was conducted in China from 1 January 2020 to 31 December 2021. All included patients diagnosed with active pulmonary TB (PTB) were evaluated both by Nutrition Risk Screening 2002 (NRS 2002) and Global Leadership Initiative on Malnutrition (GLIM) criteria. Univariate and multivariate analyses were conducted to screen the risk factors associated with malnutrition, and a new screening risk model, mainly for TB patients, was constructed. Results: A total of 14,941 cases meeting the inclusion criteria were entered into the final analysis. The malnutrition risk rate among PTB patients in China was 55.86% and 42.70%, according to the NRS 2002 and GLIM, respectively. The inconsistency rate between the two methods was 24.77%. A total of 11 clinical factors, including elderly, low body mass index (BMI), decreased lymphocyte cells, taking immunosuppressive agents, co-pleural TB, diabetes mellitus (DM), human immunodeficiency virus (HIV), severe pneumonia, decreased food intake within a week, weight loss and dialysis were identified as independent risk factors of malnutrition based on multivariate analyses. A new nutritional risk screening model was constructed for TB patients with a diagnostic sensitivity of 97.6% and specificity of 93.1%. Conclusions: Active TB patients have severe malnutrition status according to screening by the NRS 2002 and GLIM criteria. The new screening model is recommended for PTB patients as it is more closely tailored to the characteristics of TB.

2.
J Am Chem Soc ; 143(41): 17079-17089, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34610744

RESUMO

In parallel with advances in the synthesis of solid-state ionic conductors, there is a need to understand the underlying mechanisms behind their improved ionic conductivities. This can be achieved by obtaining an atomic level picture of the interplay between the structure of materials and the resultant ionic diffusion processes. To this end, the structure and dynamics of Mg2+-stabilized rotor phase material γ-Na3PO4, characterized by neutron scattering, are detailed in this work. The Mg2+-stabilized rotor phase is found to be thermally stable from 4 to 650 K. However, signatures of orientational disorder of the phosphate anions are also evident in the average structure. Long-range Na+ self-diffusion was probed by quasi-elastic neutron scattering and subsequently modeled via a jump diffusion matrix with consideration of the phosphate anion rotations. The resultant diffusion model points directly to coupled anion-cation dynamics. Our approach highlights the importance of considering the whole system when developing an atomic level picture of structure and dynamics, which is critical in the rational design and optimization of energy materials.

3.
Nat Commun ; 12(1): 1256, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33623048

RESUMO

Rechargeable solid-state sodium-ion batteries (SSSBs) hold great promise for safer and more energy-dense energy storage. However, the poor electrochemical stability between current sulfide-based solid electrolytes and high-voltage oxide cathodes has limited their long-term cycling performance and practicality. Here, we report the discovery of the ion conductor Na3-xY1-xZrxCl6 (NYZC) that is both electrochemically stable (up to 3.8 V vs. Na/Na+) and chemically compatible with oxide cathodes. Its high ionic conductivity of 6.6 × 10-5 S cm-1 at ambient temperature, several orders of magnitude higher than oxide coatings, is attributed to abundant Na vacancies and cooperative MCl6 rotation, resulting in an extremely low interfacial impedance. A SSSB comprising a NaCrO2 + NYZC composite cathode, Na3PS4 electrolyte, and Na-Sn anode exhibits an exceptional first-cycle Coulombic efficiency of 97.1% at room temperature and can cycle over 1000 cycles with 89.3% capacity retention at 40 °C. These findings highlight the immense potential of halides for SSSB applications.

4.
ACS Appl Mater Interfaces ; 11(46): 43138-43145, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31642661

RESUMO

Enabling long cyclability of high-voltage oxide cathodes is a persistent challenge for all-solid-state batteries, largely because of their poor interfacial stabilities against sulfide solid electrolytes. While protective oxide coating layers such as LiNbO3 (LNO) have been proposed, its precise working mechanisms are still not fully understood. Existing literature attributes reductions in interfacial impedance growth to the coating's ability to prevent interfacial reactions. However, its true nature is more complex, with cathode interfacial reactions and electrolyte electrochemical decomposition occurring simultaneously, making it difficult to decouple each effect. Herein, we utilized various advanced characterization tools and first-principles calculations to probe the interfacial phenomenon between solid electrolyte Li6PS5Cl (LPSCl) and high-voltage cathode LiNi0.85Co0.1Al0.05O2 (NCA). We segregated the effects of spontaneous reaction between LPSCl and NCA at the interface and quantified the intrinsic electrochemical decomposition of LPSCl during cell cycling. Both experimental and computational results demonstrated improved thermodynamic stability between NCA and LPSCl after incorporation of the LNO coating. Additionally, we revealed the in situ passivation effect of LPSCl electrochemical decomposition. When combined, both these phenomena occurring at the first charge cycle result in a stabilized interface, enabling long cyclability of all-solid-state batteries.

5.
Sci Data ; 6(1): 86, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189922

RESUMO

Two-dimensional (2D) materials have been a hot research topic in the last decade, due to novel fundamental physics in the reduced dimension and appealing applications. Systematic discovery of functional 2D materials has been the focus of many studies. Here, we present a large dataset of 2D materials, with more than 6,000 monolayer structures, obtained from both top-down and bottom-up discovery procedures. First, we screened all bulk materials in the database of Materials Project for layered structures by a topology-based algorithm and theoretically exfoliated them into monolayers. Then, we generated new 2D materials by chemical substitution of elements in known 2D materials by others from the same group in the periodic table. The structural, electronic and energetic properties of these 2D materials are consistently calculated, to provide a starting point for further material screening, data mining, data analysis and artificial intelligence applications. We present the details of computational methodology, data record and technical validation of our publicly available data ( http://www.2dmatpedia.org/ ).

6.
Proc Natl Acad Sci U S A ; 116(13): 5872-5877, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30850523

RESUMO

Nanoscale multipoint structure-function analysis is essential for deciphering the complexity of multiscale biological and physical systems. Atomic force microscopy (AFM) allows nanoscale structure-function imaging in various operating environments and can be integrated seamlessly with disparate probe-based sensing and manipulation technologies. Conventional AFMs only permit sequential single-point analysis; widespread adoption of array AFMs for simultaneous multipoint study is challenging owing to the intrinsic limitations of existing technological approaches. Here, we describe a prototype dispersive optics-based array AFM capable of simultaneously monitoring multiple probe-sample interactions. A single supercontinuum laser beam is utilized to spatially and spectrally map multiple cantilevers, to isolate and record beam deflection from individual cantilevers using distinct wavelength selection. This design provides a remarkably simplified yet effective solution to overcome the optical cross-talk while maintaining subnanometer sensitivity and compatibility with probe-based sensors. We demonstrate the versatility and robustness of our system on parallel multiparametric imaging at multiscale levels ranging from surface morphology to hydrophobicity and electric potential mapping in both air and liquid, mechanical wave propagation in polymeric films, and the dynamics of living cells. This multiparametric, multiscale approach provides opportunities for studying the emergent properties of atomic-scale mechanical and physicochemical interactions in a wide range of physical and biological networks.


Assuntos
Microscopia de Força Atômica/métodos , Animais , Camundongos , Miócitos Cardíacos/ultraestrutura , Nanotecnologia/métodos , Imagem Óptica/métodos , Polímeros/química , Relação Estrutura-Atividade , Propriedades de Superfície
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