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1.
Small ; : e2402841, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693072

RESUMO

Developing lightweight composite with reversible switching between microwave (MW) absorption and electromagnetic interference (EMI) shielding is promising yet remains highly challenging due to the completely inconsistent attenuation mechanism for electromagnetic (EM) radiation. Here, a lightweight vanadium dioxide/expanded polymer microsphere composites foam (VO2/EPM) is designed and fabricated with porous structures and 3D VO2 interconnection, which possesses reversible switching function between MW absorption and EMI shielding under thermal stimulation. The VO2/EPM exhibits MW absorption with a broad effective absorption bandwidth of 3.25 GHz at room temperature (25 °C), while provides EMI shielding of 23.1 dB at moderately high temperature (100 °C). This reversible switching performance relies on the porous structure and tunability of electrical conductivity, complex permittivity, and impedance matching, which are substantially induced by the convertible crystal structure and electronic structure of VO2. Finite element simulation is employed to qualitatively investigate the change in interaction between EM waves and VO2/EPM before and after the phase transition. Moreover, the application of VO2/EPM is demonstrated with a reversible switching function in controlling wireless transmission on/off, showcasing its excellent cycling stability. This kind of smart material with a reversible switching function shows great potential in next-generation electronic devices.

2.
Chemistry ; 30(40): e202400537, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38703390

RESUMO

With the popularization of 5G technology and artificial intelligence, thermally conductive epoxies with self-healing ability will be widely used in flexible electronic materials. Although many compounds containing both performances have been synthesized, there is little systematic theory to explain the coordination mechanism. In this paper, alkyl chains of different lengths were introduced to epoxies to discuss the thermally conductive, the self-healing performance, and the synergistic effect. A series of electronic-grade biphenyl epoxies (4,4'-bis(oxiran-2-ylmethoxy)-1,1'-biphenyl (1), 4,4'-bis(2-(oxiran-2-yl)ethoxy)-1,1'-biphenyl (2), 4,4'-bis(3-(oxiran-2-yl)propoxy)-1,1'-biphenyl (3), and 4,4'-bis(4-(oxiran-2-yl)butoxy)-1,1'-biphenyl (4) were synthesized and characterized. Furthermore, they were cured with decanedioic acid to produce polymers. Results showed that alkyl chains can both affect the two properties, and the epoxies suitable for specific application scenarios can be prepared by adjusting the length of alkyl chains. In terms of thermal conductivity, compound 1 was a most promising material. However, compound 4 was expected to be utilized in flexible electronic devices because of its acceptable thermal conductivity, self-healing ability, transparency, and flexibility.

3.
Sci Rep ; 14(1): 18786, 2024 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138254

RESUMO

Rest-activity behavior clusters within individuals to form patterns are of significant importance to their intrinsic capacity (IC), yet they have rarely been studied. A total of 1253 community-dwelling older adults were recruited between July and December 2021 based on the baseline survey database of the Fujian Prospective Cohort Study on Aging. Latent profile analysis was used to identify profiles of participants based on rest-activity behaviors, whereas logistic regression analysis was carried out to investigate the relationship between profiles and IC. We identified three latent profiles including: (1) Profile 1-labeled "Gorillas": High physical activity (PA), moderate sedentary behaviors (SB), screen time (ST) and sleep (n = 154, 12%), (2) Profile 2-labeled as "Zebras": Moderate PA, low SB, ST and high sleep (n = 779, 62%), and (3) Profile 3-labeled as"Koalas": High SB, ST, low PA and sleep (n = 320, 26%). Logistic regression revealed a negative correlation between low IC and the "Gorillas" profile (ß = - 0.945, P < 0.001) as well as the "Zebras" profile (ß = - 0.693, P < 0.001) among community-dwelling older adults, with the "Koalas" profile showing the weakest IC compared to the other profiles. The demographic traits i.e., female, older age, living alone, and low educational level also correlated with low IC. Identifying trends of rest-activity behaviors may help in drawing focus on older adults at risk of decreasing IC, and develop personalized improvement plans for IC.


Assuntos
Exercício Físico , Vida Independente , Descanso , Comportamento Sedentário , Sono , Humanos , Idoso , Feminino , Masculino , Exercício Físico/fisiologia , Sono/fisiologia , Descanso/fisiologia , Estudos Prospectivos , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Pessoa de Meia-Idade , Tempo de Tela
4.
BMC Med Genomics ; 17(1): 59, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383373

RESUMO

BACKGROUND: Heart failure (HF) is a prevalent clinical syndrome with diverse etiologies. It is crucial to identify novel therapeutic targets based on underlying causes. Here, we aimed to use proteome-wide Mendelian randomization (MR) analyses to identify the associations between genetically predicted elevated levels of circulating proteins and distinct HF outcomes, along with specific HF etiologies. METHODS: Protein quantitative trait loci (pQTL) data for circulating proteins were sourced from the Atherosclerosis Risk in Communities (ARIC) study, encompassing 7,213 individuals and profiling 4,657 circulating proteins. Genetic associations for outcomes were obtained from the HERMES Consortium and the FinnGen Consortium. Colocalization analysis was employed to assess the impact of linkage disequilibrium on discovered relationships. For replication, two-sample MR was conducted utilizing independent pQTL data from the deCODE study. Multivariable MR (MVMR) and two-step MR were further conducted to investigate potential mediators. RESULTS: Two proteins (PCSK9 and AIDA) exhibited associations with HF in patients with coronary heart disease (CHD), and four proteins (PCSK9, SWAP70, NCF1, and RELT) were related with HF in patients receiving antihypertensive medication. Among these associations, strong evidence from subsequent analyses supported the positive relationship between genetically predicted PCSK9 levels and the risk of HF in the context of CHD. Notably, MVMR analysis revealed that CHD and LDL-C did not exert a complete mediating effect in this relationship. Moreover, two-step MR results yielded valuable insights into the potential mediating proportions of CHD or LDL-C in this relationship. CONCLUSIONS: Our findings provide robust evidence supporting the association between PCSK9 and concomitant HF and CHD. This association is partly elucidated by the influence of CHD or LDL-C, underscoring the imperative for additional validation of this connection and a thorough exploration of the mechanisms through which PCSK9 directly impacts ischemic HF.


Assuntos
Insuficiência Cardíaca , Proteoma , Humanos , Pró-Proteína Convertase 9/genética , LDL-Colesterol , Análise da Randomização Mendeliana , Insuficiência Cardíaca/genética , Estudo de Associação Genômica Ampla
5.
Front Public Health ; 12: 1389297, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38912262

RESUMO

Background: Pre-frailty represents an ideal window of opportunity to potentially prevent frailty and disability. Early and effective interventions to delay or reverse pre-frailty are public health imperative. The present trial aims to evaluate the effectiveness and underlying mechanisms of mobile health (mHealth) platform-supported lifestyle-integrated multicomponent exercise (PF-Life) to reverse pre-frailty in community-dwelling older adults. Methods: This is an open-label, prospective, two-arm parallel randomized controlled trial with allocation concealment and outcome assessment blinding. We aim to recruit 140 pre-frail community-dwelling older adults who will be randomized into two groups. The control group will receive a health education program, while the intervention group will receive PF-Life training as planned for 1 year. The proportion of pre-frailty, functional performance (muscular strength, aerobic capacity, flexibility, and balance), body composition, and physical activity will be measured at pre-intervention, post-intervention, and 12-month follow-up. Inflammatory biomarkers will also be collected to explore the underlying mechanisms. Discussion: This is the first study to evaluate the effects of a novel digital lifestyle-integrated multicomponent exercise for pre-frail older people. The results of this trial will provide much-needed information on the short-and long-term effects of PF-Life based on functional performance and body composition. Meanwhile, inflammatory biomarkers and physical activity levels will be used to elucidate the underlying mechanisms of PF-Life. The findings from this trial will provide evidence for the effectiveness of lifestyle multicomponent exercise intervention supported by the mHealth platform that may reverse or even halt the onset of frailty. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=176477, identifier ChiCTR2200063431.


Assuntos
Vida Independente , Telemedicina , Humanos , Idoso , Masculino , Feminino , Estudos Prospectivos , Exercício Físico , Fragilidade/prevenção & controle , Idoso Fragilizado , Estilo de Vida , Terapia por Exercício/métodos , Idoso de 80 Anos ou mais
6.
ESC Heart Fail ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39105329

RESUMO

BACKGROUND AND AIMS: As the incidence of heart failure (HF) increases, the need for practical tools to evaluate the long-term prognosis in these patients remains critical. Our study aimed to develop a 48 month prediction model for all-cause mortality in decompensated HF patients using available clinical indicators. METHODS: HF patients (n = 503), 60 years or older, were divided into a training cohort (n = 402) and a validation cohort (n = 101). Data on demographics, comorbidities, laboratory results and medications were gathered. Prediction models were developed using the Prognostic Nutritional Index (PNI), cholinesterase (ChE) and a multifactorial nomogram incorporating clinical variables. These models were constructed using the least absolute shrinkage and selection operator algorithm and multivariate logistic regression analysis. The performance of the model was assessed in terms of calibration, discrimination and clinical utility. RESULTS: The mean age was 77.11 ± 8.85 years, and 216 (42.9%) were female. The multifactorial nomogram included variables of ChE, lymphocyte count, albumin, serum creatinine and N-terminal pro-brain natriuretic peptide (all P < 0.05). In the training cohort, the nomogram's C-index was 0.926 [95% confidence interval (CI) 0.896-0.950], outperforming the PNI indices at 0.883 and ChE at 0.804 (Z-tests, P < 0.05). The C-index in the validation cohort was 0.913 (Z-tests, P < 0.05). Calibration and decision curve analysis confirmed model reliability, indicating a more significant net benefit than PNI and ChE alone. CONCLUSIONS: Both the ChE- and PNI-based prediction models effectively predict the long-term prognosis in patients over 60 years of age with decompensated HF. The multifactorial nomogram model shows superior performance, improving clinical decision-making and patient outcomes.

7.
J Am Med Dir Assoc ; 25(9): 105117, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945172

RESUMO

OBJECTIVE: Although the cardiac benefits of maintaining a lifelong exercise routine are undisputed, to what extent late-in-life exercise training can ameliorate cardiac aging remains unclear. We examined the impact of a 12-month exercise training program on cardiac reserve, static cardiac structure, and cardiac function in older adults. DESIGN: This study was a single-center, randomized trial using Zelen design. Participants in the center-based exercise (CBE) group underwent an individualized multicomponent exercise training program. SETTING AND PARTICIPANTS: In total, 120 community-dwelling older adults aged 65-85 years were evenly divided into a CBE group and a control group. METHODS: The primary outcome indicator was absolute change in peak oxygen uptake (peakVO2) per kilogram from baseline to 12 months. The secondary outcome indicators were the absolute changes in other cardiopulmonary exercise test indices and cardiac magnetic resonance parameters. This study has been registered at the Chinese Clinical Trial Registry Network (ChiCTR2400081824). RESULTS: In total, 47 older adults in the control group and 49 in the CBE group ultimately completed the 12-month follow-up and were analyzed. Of all participants, 52 (46.4%) were men, and the mean age was 71.22 ± 4.55 years. The absolute change in peakVO2/kg was significantly different between the CBE and control groups by +3.32 mL/kg/min (95% CI 2.10-4.53; P < .001), and a sex-related difference was observed. Additionally, the right ventricular peak filling and ejection rate improved to a greater degree in the CBE than control group (+65.57 mL/s, P = .006; +56.39 mL/s, P = .026, respectively). CONCLUSIONS AND IMPLICATIONS: A 12-month exercise training program started later in life was effective in improving cardiopulmonary reserve, and men showed a better response to training than women. The right ventricular function increased after late-in-life exercise training.

8.
Front Cardiovasc Med ; 11: 1320222, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333417

RESUMO

Background: Although atherosclerosis (AS) can affect multiple vascular beds, previous studies have focused on the analysis of single-site AS plaques. Objective: The aim of this study is to explore the differences or similarities in the characteristics of atherosclerotic plaque found in the internal carotid artery, cerebral artery, and coronary artery between patients with atherosclerotic cardiovascular disease (ASCVD) and those without events. Methods: Patients aged ≥ 18 years who underwent both high-resolution vessel wall imaging (HR-VWI) and coronary computed tomography angiography (CCTA) were retrospectively collected and categorized into the ASCVD group and the non-event group. The plaques were then categorized into culprit plaques, non-culprit plaques, and non-event plaques. Plaque morphological data such as stenosis, stenosis grades, plaque length (PL), plaque volume (PV), minimal lumen area (MLA), enhancement grade, and plaque composition data such as calcified plaque volume (CPV), fibrotic plaque volume (FPV), fibro-lipid plaque volume (FLPV), lipid plaque volume (LPV), calcified plaque volume ratio (CPR), fibrotic plaque volume ratio (FPR), fibro-lipid plaque ratio (FLPR), lipid plaque volume ratio (LPR), intraplaque hemorrhage volume (IPHV), and intraplaque hemorrhage volume ratio (IPHR)were recorded and analyzed. Results: A total of 44 patients (mean age 66 years, SD 9 years, 28 men) were included. In cervicocephalic plaques, the ASCVD group had more severe stenosis grades (p = 0.030) and demonstrated significant differences in LPV, LPR, and CPV (p = 0.044, 0.030, 0.020) compared with the non-event group. In coronary plaques, the ASCVD group had plaques with greater stenosis (p < 0.001), more severe stenosis grades (p < 0.001), larger volumes (p = 0.001), longer length (p = 0.008), larger FLPV (p = 0.012), larger FPV (p = 0.002), and higher FPR (p = 0.043) compared with the non-event group. There were significant differences observed in stenosis (HR-VWI, CCTA: p < 0.001, p < 0.001), stenosis grades (HR-VWI, CCTA: p < 0.001, p < 0.001), plaque length (HR-VWI, CCTA: p = 0.028, p < 0.001), and plaque volume (HR-VWI, CCTA: p = 0.013, p = 0.018) between the non-event plaque, non-culprit plaque, and culprit plaque. In the image analysis of HR-VWI, there were differences observed between IPHR (p < 0.001), LPR (p = 0.001), FPV (p = 0.011), and CPV (p = 0.015) among the three groups of plaques. FLPV and FPV were significantly different among the three different plaque types from the coronary artery (p = 0.043, p = 0.022). Conclusion: There is a consistent pattern of change in plaque characteristics between the cervicocephalic and coronary arteries in the same patient.

9.
Nanomicro Lett ; 16(1): 134, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411757

RESUMO

The remarkable properties of carbon nanotubes (CNTs) have led to promising applications in the field of electromagnetic interference (EMI) shielding. However, for macroscopic CNT assemblies, such as CNT film, achieving high electrical and mechanical properties remains challenging, which heavily depends on the tube-tube interactions of CNTs. Herein, we develop a novel strategy based on metal-organic decomposition (MOD) to fabricate a flexible silver-carbon nanotube (Ag-CNT) film. The Ag particles are introduced in situ into the CNT film through annealing of MOD, leading to enhanced tube-tube interactions. As a result, the electrical conductivity of Ag-CNT film is up to 6.82 × 105 S m-1, and the EMI shielding effectiveness of Ag-CNT film with a thickness of ~ 7.8 µm exceeds 66 dB in the ultra-broad frequency range (3-40 GHz). The tensile strength and Young's modulus of Ag-CNT film increase from 30.09 ± 3.14 to 76.06 ± 6.20 MPa (~ 253%) and from 1.12 ± 0.33 to 8.90 ± 0.97 GPa (~ 795%), respectively. Moreover, the Ag-CNT film exhibits excellent near-field shielding performance, which can effectively block wireless transmission. This innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices.

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