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1.
Support Care Cancer ; 32(10): 649, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256232

RESUMO

PURPOSE: Despite the increasing research on cancer patient caregivers, there is still a lack of detailed understanding about the experiences of spouses caring for elderly colorectal cancer patients. This study aimed to fill this gap by examining the caregiving experiences of spouses during palliative chemotherapy for elderly Chinese colorectal cancer patients. METHODS: Using a qualitative descriptive design, we recruited spousal caregivers of elderly colorectal cancer patients undergoing palliative chemotherapy. Semistructured interviews were conducted, and thematic analysis was employed to analyse the data. RESULTS: Sixteen caregivers aged 60 to 82 years participated in the interviews. The analysis revealed three main themes: ambivalence, multiple role adaptation to conflicts, and the coexistence of hope and pressure. These themes shed light on the behaviors of older caregivers and the challenges they face, including physical and psychosocial issues associated with aging. CONCLUSION: This study highlights the significant stress and challenges experienced by older caregivers, characterized by intertwined emotions such as anxiety about their spouses' health deterioration, exhaustion from long-term care responsibilities, and anticipation of treatment outcomes.


Assuntos
Cuidadores , Neoplasias Colorretais , Cuidados Paliativos , Pesquisa Qualitativa , Humanos , Idoso , Cuidadores/psicologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/psicologia , Cuidados Paliativos/métodos , Cuidados Paliativos/psicologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Incerteza , Cônjuges/psicologia , Adaptação Psicológica , Estresse Psicológico/etiologia , Estresse Psicológico/psicologia , Entrevistas como Assunto , China
2.
Adv Mater ; : e2409838, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39268782

RESUMO

Lithium-ion batteries using quasi-solid gel electrolytes (QSEs) have gained increasing interest due to their enhanced safety features. However, their commercial viability is hindered by low ionic conductivity and poor solid-solid contact interfaces. In this study, a QSE synthesized by in situ polymerizing methyl methacrylate (MMA) in 1,2-dimethoxyethane (DME)-based electrolyte is introduced, which exhibits remarkable performance in high-loading graphite||LiNi0.8Co0.1Mn0.1O2 (NCM811) pouch cells. Owing to the unique solvent-lacking solvation structure, the graphite exfoliation caused by the well-known solvent co-intercalation is prohibited, and this unprecedented phenomenon is found to be universal for other graphite-unfriendly solvents. The high ionic conductivity and great interfacial contact provided by DME enable the quasi-solid graphite||NCM811 pouch cell to demonstrate superior C-rate capability even at a high cathode mass loading (17.5 mg cm-2), surpassing liquid carbonate electrolyte cells. Meanwhile, the optimized QSE based on carbonates exhibits excellent cycle life (92.4% capacity retention after 1700 cycles at 0.5C/0.5C) and reliable safety under harsh conditions. It also outperforms liquid electrolytes in other high-energy-density batteries with larger volume change. These findings elucidate the polymer's pivotal role in QSEs, offering new insights for advancing quasi-solid-state battery commercialization.

3.
Br J Hosp Med (Lond) ; 85(9): 1-21, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39347669

RESUMO

Aims/Background Pre-frailty is common in patients undergoing maintenance hemodialysis (MHD). Without proper management, it can quickly worsen and progress into frailty, leading to various adverse clinical outcomes. Therefore, timely interventions for pre-frail MHD patients are crucial. However, the response of pre-frail MHD patients to such interventions is currently unclear. This study evaluated the effect of a multicomponent intervention on changes in pre-frailty status, risk factors for frailty, quality of life, and clinical outcomes in pre-frail patients undergoing MHD. Methods Sixty MHD patients were randomly assigned to intervention (received a 12-week multicomponent intervention) and control (received standard care) groups, with 30 participants per group, between February and May 2018. Data were collected at baseline and at 3 and 9 months thereafter. Analyzed outcomes included changes in pre-frailty status, frailty risk factors (such as albumin level, pain, and anxiety), quality of life, and clinical outcomes during the follow-up period. Results Data from a total of 58 MHD patients were collected at three time points. At week 12, frailty scores were 0.9 points lower in the intervention group compared to the control group (p = 0.007). The intervention group showed a 26.2% higher proportion of patients who improved from pre-frailty to non-frailty compared to the control group (p = 0.029), and a 25.9% lower proportion of patients who progressed from pre-frailty to frailty (p = 0.021). Additionally, improvements in albumin levels, pain, anxiety, and quality of life were more significant in the intervention group (all p < 0.05). Although there were fewer incidents of falls and rehospitalizations in the intervention group during follow-up, these differences did not reach statistical significance (all p > 0.05). Conclusion This study validates the effectiveness and practicality of a multicomponent intervention in improving pre-frailty status, frailty risk factors, and quality of life in patients undergoing MHD. Clinical Trial Registration Chinese Clinical Trial Registry (ChiCTR-IOR-17012176).


Assuntos
Fragilidade , Qualidade de Vida , Diálise Renal , Humanos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Fatores de Risco , Falência Renal Crônica/terapia
4.
Pediatr Blood Cancer ; : e31288, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189644

RESUMO

BACKGROUND: Accurate molecular and clinical stratification of patients with central nervous system (CNS) non-germinomatous germ cell tumors (NGGCTs) remains challenging, impeding the development of personalized therapeutic approaches. Herein, we investigated the translational significance of cerebrospinal fluid (CSF) circulating tumor DNA (ctDNA) in pediatric NGGCTs to identify characteristic features of CNS NGGCTs and to identify a subset of patients for whom the presence of residual disease is a risk factor and an indicator of shorter progression-free survival (PFS) and overall survival (OS). METHODS: Medical records of patients with CNS NGGCTs between January 1, 2018 and December 31, 2022 were reviewed retrospectively. RESULTS: The cohort consisted of 11 male and six female patients. Tumor markers were elevated in four of the five people who underwent surgery. The remaining 12 patients were diagnosed with malignant NGGCTs according to elevated tumor markers. Among them, ctDNA before chemotherapy as well as ctDNA clearance were consistently associated with PFS and OS (p < .05). By setting a ctDNA positivity threshold of 6%, patients with high ctDNA (above the threshold) levels, which had limitation due to the selection based on optimal statistic from the survival analysis, had significantly inferior 5-year PFS and OS compared to those with low levels (below the threshold). ctDNA or ctDNA clearance combined with the presence of residual disease predicted significantly worse OS and PFS (p < .05). CONCLUSIONS: CSF ctDNA might allow the study of genomic evolution and the characterization of tumors in pediatric NGGCTs. CSF ctDNA analysis may facilitate the clinical management of pediatric NGGCT patients, and aid in designing personalized therapeutic strategies.

5.
Front Pharmacol ; 15: 1419369, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086394

RESUMO

Background: High-intensity chemotherapy can cause life-threatening complications in pediatric patients. Therefore, this study investigated safety and efficacy of long-acting pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF; Jinyouli®) in children undergoing high-intensity chemotherapy. Methods: Treatment-naive patients received post-chemotherapy PEG-rhG-CSF as primary prophylaxis for two cycles. The primary endpoints were drug-related adverse events (AEs) and bone pain scores. Secondary endpoints included grade 3-4 neutropenia, duration of neutropenia recovery, absolute neutrophil count changes, febrile neutropenia (FN), reduced chemotherapy intensity, antibiotic usage, and AE severity. The cost-effectiveness of PEG-rhG-CSF was compared with that of rhG-CSF (Ruibai®). Results: Here, 307 and 288 patients underwent one and two PEG-rhG-CSF cycles, respectively. Ninety-one patients experienced drug-related AEs, primarily bone pain (12.7%). Moreover, Grade 3-4 neutropenia and FN were observed. Median FN durations were 3.0 days in both cycles. No drug-related delays were observed during chemotherapy. One patient experienced grade 4 neutropenia-induced reduction in chemotherapy intensity during cycle 2. In total, 138 patients received antibiotics. PEG-rhG-CSF exhibited superior cost-effectiveness compared to rhG-CSF. Conclusion: Our findings indicate that PEG-rhG-CSF is safe, efficient, and cost-effective in pediatric patients undergoing high-intensity chemotherapy, providing preliminary evidence warranting further randomized controlled trials.

6.
Small ; : e2403518, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016114

RESUMO

2D Ti3C2Tx MXene-based film electrodes with metallic conductivity and high pseudo-capacitance are of considerable interest in cutting-edge research of capacitive deionization (CDI). Further advancement in practical use is however impeded by their intrinsic limitations, e.g., tortuous ion diffusion pathway of layered stacking, vulnerable chemical stability, and swelling-prone nature of hydrophilic MXene nanosheet in aqueous environment. Herein, a nanoporous 2D/2D heterostructure strategy is established to leverage both merits of holey MXene (HMX) and holey graphene oxide (HGO) nanosheets, which optimize ion transport shortcuts, alleviate common restacking issues, and improve film's mechanical and chemical stability. In this design, the nanosized in-plane holes in both handpicked building blocks build up ion diffusion shortcuts in the composite laminates to accelerate the transport and storage of ions. As a direct outcome, the HMX/rHGO films exhibit remarkable desalination capacity of 57.91 mg g-1 and long-term stability in 500 mg L-1 NaCl solution at 1.2 V. Moreover, molecular dynamics simulations and ex situ wide angle X-ray scattering jointly demonstrate that the conductive 2D/2D networks and ultra-short ion diffusion channels play critical roles in the ion intercalation/deintercalation process of HMX/rHGO films. The study paves an alternative design concept of freestanding CDI electrodes with superior ion transport efficiency.

7.
Support Care Cancer ; 32(8): 501, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985345

RESUMO

OBJECTIVE: This study aims to use structural equation modeling to explore the pathways and effect sizes of factors influencing the adherence of postoperative patients with digestive tract tumor to oral nutritional supplements, providing a theoretical basis for future nursing intervention measures. METHODS: A total of 300 postoperative patients with digestive tract tumor within 30 days after surgery were conveniently sampled. Surveys were conducted using a General Information Questionnaire, Morisky Medication Adherence Scale, Digestive System Tumor Patient Nutrition Knowledge-Attitude-Behavior Questionnaire, Multidimensional Social Perception Scale, Beliefs about Medical Questionnaire, and General Self-Efficacy Scale. Structural equation modeling was employed to analyze the factors and pathways affecting adherence with oral nutritional supplements. RESULTS: The adherence score of postoperative patients with digestive tract tumor to oral nutritional supplements was 1.61 ± 1.38. The structural equation model had a good fit (χ2/df = 2.685, GFI = 0.930, CFI = 0.913, AGFI = 0.887, IFI = 0.915, and RMSEA = 0.075). Nutrition knowledge, social support, medication beliefs, and self-efficacy were found to be factors influencing adherence with oral nutritional supplements in postoperative patients with digestive tract tumor, with total effects of 0.539, 0.264, 0.215, and 0.180, respectively. Nutrition knowledge indirectly affected adherence through self-efficacy and medication beliefs, while social support indirectly affected adherence through self-efficacy. CONCLUSION: Adherence with oral nutritional supplements in postoperative patients with digestive tract tumor is at a low level. Improving social support, enhancing patients nutrition knowledge, increasing self-efficacy, and strengthening medication beliefs are effective ways to improve patient adherence.


Assuntos
Suplementos Nutricionais , Conhecimentos, Atitudes e Prática em Saúde , Adesão à Medicação , Autoeficácia , Humanos , Estudos Transversais , Feminino , Masculino , Pessoa de Meia-Idade , Adesão à Medicação/estatística & dados numéricos , Inquéritos e Questionários , Idoso , Adulto , Neoplasias do Sistema Digestório/cirurgia , Neoplasias do Sistema Digestório/psicologia , Apoio Social , Neoplasias Gastrointestinais/cirurgia , Neoplasias Gastrointestinais/psicologia , Período Pós-Operatório
8.
Adv Mater ; 36(36): e2406386, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38973220

RESUMO

A majority of flexible and wearable electronics require high operational voltage that is conventionally achieved by serial connection of battery unit cells using external wires. However, this inevitably decreases the energy density of the battery module and may cause additional safety hazards. Herein, a bipolar textile composite electrode (BTCE) that enables internal tandem-stacking configuration to yield high-voltage (6 to 12 V class) solid-state lithium metal batteries (SSLMBs) is reported. BTCE is comprised of a nickel-coated poly(ethylene terephthalate) fabric (NiPET) core layer, a cathode coated on one side of the NiPET, and a Li metal anode coated on the other side of the NiPET. Stacking BTCEs with solid-state electrolytes alternatively leads to the extension of output voltage and decreased usage of inert package materials, which in turn significantly boosts the energy density of the battery. More importantly, the BTCE-based SSLMB possesses remarkable capacity retention per cycle of over 99.98% over cycling. The composite structure of BTCE also enables outstanding flexibility; the battery keeps stable charge/discharge characteristics over thousands of bending and folding. BTCE shows great promise for future safe, high-energy-density, and flexible SSLMBs for a wide range of flexible and wearable electronics.

9.
J Adv Nurs ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001661

RESUMO

AIM: To explore the mechanism of proactive personality influence on nurses' sense of social responsibility through a serial multiple mediation model of volunteering motivation and self-efficacy. DESIGN: Further analysis of a cross-sectional and survey-based study. METHODS: In June 2023, a study was conducted with 722 Chinese nurses from four hospitals. Data were collected using the Proactive Personality Scale, the Self-Efficacy Scale, the Motivation to Volunteer Scale and the Nurses' Sense of Social Responsibility Scale. Structural equation modelling was used to analyse the relationship between nurses' sense of social responsibility and its correlative factors. RESULTS: Structural equation modelling showed a good model fit. Proactive personality, self-efficacy and motivation to volunteer can directly influence nurses' sense of social responsibility (ß = .12, ß = .04, ß = .50, p < .05). According to the test of chained mediation effects, proactive personality was significant through a single mediation path of self-efficacy (Z = 2.33, p < .05) and motivation to volunteer (Z = 7.32, p < .05) and through successive mediation paths of both variables (Z = 3.33, p < .05). CONCLUSION: A proactive personality can motivate nurses' social responsibility. Therefore, prompting nurses to be more proactive can effectively enhance nurses' sense of social responsibility. REPORTING METHOD: This study was reported following the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist for cross-sectional studies. PATIENT OR PUBLIC CONTRIBUTION: This study explored the mechanisms influencing nurses' sense of social responsibility at the end of the epidemic. The results may inform the maintenance of high levels of long-term effects of nurses' social responsibility and shed light on building a standing workforce for public health emergencies.

10.
Sci Rep ; 14(1): 15222, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956233

RESUMO

The critical value of rock failure is determined by irreversible deformation (inelastic deformation, damage, and other internal dissipation) processes and external conditions before rock failure. Nevertheless, a thorough explanation of the mechanism causing cracks in rock material has not yet been provided. The strain energy theory is applied in this work to assess the initiation of rock cracks and investigate the relationship between energy digestion and rock strength. Firstly, the uniaxial compression test was conducted on sandstone samples under quasi-static loading conditions and the results of energy evolution, non-linear cumulative digestion, and stored ultimate energy were obtained. Then, a novel algorithm for assessing the initiation of rock cracks has been put forth. The concept of energy digestion index (EDI), which is the ratio of digested energy over the external loading energy, has been developed to characterize the energy absorption capacity of rock material. The result shows a relationship between the maximum growth rate of energy digestion and the increasing rate of variable elasticity modulus and crack initiation. The mechanical characteristics and peak strength of the rock material are negatively correlated with the EDI. By monitoring the digested energy status, an evaluation of the residual strength is introduced based on the relationships, which will initiate further research into in-situ monitoring and failure prediction.

11.
JAMA Dermatol ; 160(8): 891-892, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38865150

RESUMO

A woman in her 30s presented with mildly itchy skin nodules in the vulvar region for 1 year, which occurred during pregnancy and increased gradually in size and number without any treatments. What is your diagnosis?


Assuntos
Doenças da Vulva , Humanos , Feminino , Doenças da Vulva/diagnóstico , Doenças da Vulva/patologia , Neoplasias Vulvares/patologia , Neoplasias Vulvares/diagnóstico , Biópsia , Vulva/patologia
12.
BMC Nurs ; 23(1): 380, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840132

RESUMO

BACKGROUND: Oral nutritional supplements are one of the preferred methods of nutritional support for postoperative patients. This study aims to investigate the current status of oral nutritional supplements compliance in postoperative patients with digestive tract tumors and its influencing factors. METHODS: Convenience sampling was employed to select 242 patients who underwent surgery for digestive tract tumors at a tertiary hospital in Shanghai from October 2022 to July 2023 as the study subjects. Data following a normal distribution were analyzed using independent sample t-tests, ANOVA single-factor analysis, Pearson correlation analysis, and multiple linear regression analysis to determine the factors influencing compliance with oral nutritional supplements. RESULTS: A total of 252 questionnaires were distributed, with 10 invalid questionnaires excluded, resulting in an effective questionnaire rate of 96.03%. The compliance score for oral nutritional supplements in postoperative patients with digestive tract tumors was (2.40 ± 1.45), General Self-efficacy Scale (GSES) score was (24.72 ± 4.86), Multidimensional Scale of Perceived Social Support Scale (MSPSS) score was (58.67 ± 11.09), and Belief about Medicines Questionnaire Scale (BMQ) score was (0.17 ± 2.78). Multiple linear regression analysis revealed that age, adverse reactions, educational level, self-efficacy, medication beliefs, and social support were factors influencing compliance with oral nutritional supplements in postoperative patients with digestive tract tumors (P < 0.05). CONCLUSION: Our study revealed that the compliance to oral nutritional supplements among postoperative patients with digestive tract tumors was at a moderate level and was closely associated with age, educational level, adverse reactions to oral nutritional supplements, medication beliefs, social support, and self-efficacy. Nursing staff should conduct nursing assessments based on the specific circumstances of patients and their families, provide personalized health education management plans based on the patients' educational level, enhance patients' nutrition knowledge, improve patient self-efficacy, and enhance social support for patients, while further improving patient nutrition management.

13.
Analyst ; 149(10): 2956-2965, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38597984

RESUMO

Glioblastoma is the most fatal and insidious malignancy, due to the existence of the blood-brain barrier (BBB) and the high invasiveness of tumor cells. Abnormal mitochondrial viscosity has been identified as a key feature of malignancies. Therefore, this study reports on a novel fluorescent probe for mitochondrial viscosity, called ZVGQ, which is based on the twisted intramolecular charge transfer (TICT) effect. The probe uses 3-dicyanomethyl-1,5,5-trimethylcyclohexene as an electron donor moiety and molecular rotor, and triphenylphosphine (TPP) cation as an electron acceptor and mitochondrial targeting group. ZVGQ is highly selective, pH and time stable, and exhibits rapid viscosity responsiveness. In vitro experiments showed that ZVGQ could rapidly recognize to detect the changes in mitochondrial viscosity induced by nystatin and rotenone in U87MG cells and enable long-term imaging for up to 12 h in live U87MG cells. Additionally, in vitro 3D tumor spheres and in vivo orthotopic tumor-bearing models demonstrated that the probe ZVGQ exhibited exceptional tissue penetration depth and the ability to penetrate the BBB. The probe ZVGQ not only successfully visualizes abnormal mitochondrial viscosity changes, but also provides a practical and feasible tool for real-time imaging and clinical diagnosis of glioblastoma.


Assuntos
Corantes Fluorescentes , Glioblastoma , Mitocôndrias , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Humanos , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Mitocôndrias/metabolismo , Viscosidade , Linhagem Celular Tumoral , Animais , Camundongos , Camundongos Nus , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Imagem Óptica
14.
ACS Appl Mater Interfaces ; 16(17): 22482-22492, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38651802

RESUMO

Herein, we present the preparation and properties of an ultrathin, mechanically robust, quasi-solid composite electrolyte (SEO-QSCE) for solid-state lithium metal battery (SLB) from a well-defined polystyrene-b-poly(ethylene oxide) diblock copolymer (SEO), Li6.75La3Zr1.75Ta0.25O12 nanofiller, and fluoroethylene carbonate plasticizer. Compared with the ordered lamellar microphase separation of SEO, the SEO-QSCE displays bicontinuous phases, consisting of a Li+ ion conductive poly(ethylene oxide) domain and a mechanically robust framework of the polystyrene domain. Therefore, the 12 µm-thick SEO-QSCE membrane exhibits an exceptional ionic conductivity of 1.3 × 10-3 S cm-1 at 30 °C, along with a remarkable tensile strength of 5.1 MPa and an elastic modulus of 2.7 GPa. The high mechanical robustness and the self-generated LiF-rich SEI enable the SEO-QSCE to have an extraordinary lithium dendrite prohibition effect. The SLB of Li|SEO-QSCE|LiFePO4 reveals superior cycling performances at 30 °C for over 600 cycles, maintaining an initial discharge capacity of 145 mAh g-1 and a remarkable capacity retention of 81% (117 mAh g-1) after 400 cycles at 0.5 C. The high-voltage SLB of Li|SEO-QSCE|LiNi0.5Co0.3Mn0.2O2 displays good cycling stability for over 150 cycles at 30 °C. Moreover, the exceptional robustness of SEO-QSCE enables the high-voltage solid-state pouch cell of Li|SEO-QSCE|LiNi0.5Co0.3Mn0.2O2 with high flexibility and excellent safety features. The current investigation delivers a promising and innovative approach for preparing quasi-solid electrolytes with features of ultrathin design, mechanical robustness, and exceptional electrochemical performance for high-voltage SLBs.

15.
Adv Fiber Mater ; 6(1): 252-263, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495973

RESUMO

Given the abundant solar light available on our planet, it is promising to develop an advanced fabric capable of simultaneously providing personal thermal management and facilitating clean water production in an energy-efficient manner. In this study, we present the fabrication of a photothermally active, biodegradable composite cloth composed of titanium carbide MXene and cellulose, achieved through an electrospinning method. This composite cloth exhibits favorable attributes, including chemical stability, mechanical performance, structural flexibility, and wettability. Notably, our 0.1-mm-thick composite cloth (RC/MXene IV) raises the temperature of simulated skin by 5.6 °C when compared to a commercially available cotton cloth, which is five times thicker under identical ambient conditions. Remarkably, the composite cloth (RC/MXene V) demonstrates heightened solar light capture efficiency (87.7%) when in a wet state instead of a dry state. Consequently, this cloth functions exceptionally well as a high-performance steam generator, boasting a superior water evaporation rate of 1.34 kg m-2 h-1 under one-sun irradiation (equivalent to 1000 W m-2). Moreover, it maintains its performance excellence in solar desalination processes. The multifunctionality of these cloths opens doors to a diverse array of outdoor applications, including solar-driven water evaporation and personal heating, thereby enriching the scope of integrated functionalities for textiles. Supplementary Information: The online version contains supplementary material available at 10.1007/s42765-023-00345-w.

16.
Adv Mater ; 36(23): e2314063, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38444248

RESUMO

Polymer/ceramic-based composite solid electrolytes (CSE) are promising candidates for all-solid-state lithium metal batteries (SLBs), benefiting from the combined mechanical robustness of polymeric electrolytes and the high ionic conductivity of ceramic electrolytes. However, the interfacial instability and poorly understood interphases of CSE hinder their application in high-voltage SLBs. Herein, a simple but effective CSE that stabilizes high-voltage SLBs by forming multiple intermolecular coordination interactions between polyester and ceramic electrolytes is discovered. The multiple coordination between the carbonyl groups in poly(ε-caprolactone) and the fluorosulfonyl groups in anions with Li6.5La3Zr1.5Ta0.5O12 nanoparticles is directly visualized by cryogenic transmission electron microscopy and further confirmed by theoretical calculation. Importantly, the multiple coordination in CSE not only prevents the continuous decomposition of polymer skeleton by shielding the vulnerable carbonyl sites but also establishes stable inorganic-rich interphases through preferential decomposition of anions. The stable CSE and its inorganic-rich interphases enable Li||Li symmetric cells with an exceptional lifespan of over 4800 h without dendritic shorting at 0.1 mA cm-2. Moreover, the high-voltage SLB with LiNi0.5Co0.2Mn0.3O2 cathode displays excellent cycling stability over 1100 cycles at a 1C charge/discharge rate. This work reveals the underlying mechanism behind the excellent stability of coordinating composite electrolytes and interfaces in high-voltage SLBs.

17.
Adv Mater ; 36(24): e2313162, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38461368

RESUMO

The freezing shrinkage and dendritic growth are of great importance for various alloys solidified from high-temperature liquids to solids since they dominate microstructure patterns and follow-up processing. However, the microgravity freezing shrinkage dynamics is scarcely explored on the ground as it is hard to suppress the strong natural convection inside liquid alloys. Here, a series of in-orbit solidification experiments is conducted aboard the China Space Station with a long-term stable 10-5 g0 microgravity condition. The highest temperature up to 2265 K together with substantial liquid undercoolings far from a thermodynamically stable state are attained for both Nb82.7Si17.3 and Zr64V36 refractory alloys. Furthermore, the solidification under microgravity of a droplet is simulated to reveal the liquid-solid interface migration, temperature gradient, and flow field. The microgravity solidification process leads to freezing shrinkage cavities and distinctive surface dendritic microstructure patterns. The combined effects of shrinkage dynamics and liquid surface flow in outer space result in the dendrites growing not only along the tangential direction but also along the normal direction to the droplet surface. These space experimental results contribute to a further understanding of the solidification behavior of liquid alloys under a weaker convection condition, which is often masked by gravity on the ground.

18.
Angew Chem Int Ed Engl ; 63(15): e202400312, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38306324

RESUMO

The metastable liquid properties and chemical bonds beyond 2000 K remain a huge challenge for ground-based research on liquid materials chemistry. We show the strong undercooling capability, metastable liquid properties and surface wave patterns of refractory Nb-Si and Zr-V binary alloys explored in space environment. The floating droplet of Nb82.7Si17.3 eutectic alloy superheated up to 2338 K exhibited an extreme undercooling of 437 K, approaching the 0.2TE threshold for homogeneous nucleation of liquid-solid reaction. The microgravity state endowed alloy droplets with nearly perfect sphericity and thus ensured the high accuracy to determine metastable undercooled liquid properties. A special kind of swirling flow was induced for liquid alloy owing to Marangoni convection, which resulted in the spiral microstructures on Zr64V36 alloy surface during liquid-solid phase transition. The coupled impacts of surface nucleation and surface flow brought in a novel olivary shape for these binary alloys. Furthermore, the chemical bonds and atomic structures of high temperature liquids were revealed to understand the liquid properties in outer space circumstances.

19.
J Phys Chem B ; 128(4): 949-959, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38236746

RESUMO

The cellular compartmentation induced by self-assembly of natural proteins has recently attracted widespread attention due to its structural-functional significance. Among them, as a highly conserved metabolic enzyme and one of the potential targets for cancers and parasitic diseases in drug development, CTP synthase (CTPS) has also been reported to self-assemble into filamentous structures termed cytoophidia. To elucidate the dynamical mechanism of cytoophidium filamentation, we utilize single-molecule fluorescence imaging to observe the real-time self-assembly dynamics of CTPS and the coordinated assembly between CTPS and its interaction partner, Δ1-pyrroline-5-carboxylate synthase (P5CS). Significant differences exist in the direction of growth and extension when the two proteins self-assemble. The oligomer state distribution analysis of the CTPS minimum structural subunit under different conditions and the stoichiometry statistics of binding CTPS and P5CS by single-molecule fluorescence photobleach counting further confirm that the CTPS cytoophidia are mainly stacked with tetramers. CTPS can act as the nucleation core to induce the subsequent growth of the P5CS filaments. Our work not only provide evidence from the molecular level for the self-assembly and coordinated assembly (coassembly) of CTPS with its interaction partner P5CS in vitro but also offer new experimental perspectives for the dynamics research of coordinated regulation between other protein polymers.


Assuntos
Citoesqueleto , Ornitina-Oxo-Ácido Transaminase , Ornitina-Oxo-Ácido Transaminase/metabolismo , Citoesqueleto/metabolismo , Imagem Óptica
20.
Scand J Med Sci Sports ; 34(1): e14501, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37740713

RESUMO

INTRODUCTION: Walking pace is associated with various health-related outcomes. The aim of this study was to investigate the association between self-reported walking pace and the incidences of diabetic microvascular complications among participants with type 2 diabetes (T2D). METHODS: Self-reported walking pace was classified as brisk, average, or slow. The outcomes were the incidences of diabetic retinopathy, diabetic neuropathy, and diabetic nephropathy. COX proportional hazards models adjusted for sociodemographic, lifestyle, and health-related factors were used to estimate hazard ratios (HRs) and 95% CIs. RESULTS: A total of 14 518 participants with T2D in the UK Biobank (mean age 59.7 ± 7.0 years, 5028 [34.6%] women) were included. During a median follow-up of 12.5 (interquartile range: 11.6-13.4) years, 2980 participants developed diabetic microvascular complications. After adjusting for confounding factors, and compared with brisk walkers, slow walkers had a multivariable-adjusted HR of 1.98 (95% CI 1.58, 2.47) for composite diabetic microvascular complications, 1.54 (95% CI 1.11, 2.14) for diabetic retinopathy, 3.26 (95% CI 2.08, 5.11) for diabetic neuropathy, and 2.32 (95% CI 1.91, 2.82) for diabetic nephropathy. Average walking pace was associated with a higher risk for diabetic nephropathy (HR 1.51, 95 CI% 1.27-1.79) compared with brisk walking. Additionally, ≥1 diabetic microvascular complication occurred in 447 (14.7%) of participants with brisk walking pace, 1702 (19.5%) with average walking pace, and 831 (30.4%) with slow walking pace. Time from study recruitment to first diagnosis was shorter in participants who reported a slow walking pace, compared with brisk or average walkers. Among participants who had diabetic nephropathy as their first diagnosis, slow walking pace was associated with subsequent risk of a second diabetic microvascular complication (HR 3.88, 95 CI% 2.27-6.60). CONCLUSIONS: Self-reported slow walking pace is associated with a higher risk of diabetic microvascular complications among participants with T2D in this population-based cohort study.


Assuntos
Diabetes Mellitus Tipo 2 , Angiopatias Diabéticas , Nefropatias Diabéticas , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/complicações , Velocidade de Caminhada , Biobanco do Reino Unido , Bancos de Espécimes Biológicos , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/complicações , Fatores de Risco
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