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1.
Small ; 20(2): e2305321, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37658493

RESUMEN

2D MXene-Ti3 C2 Tx holds great promise in various electronic applications, especially for electromagnetic interference (EMI) shielding devices and supercapacitors. Ti3 C2 Tx synthesis typically involves the use of hazardous fluorine-containing chemicals that can result in the formation of inert fluoride functional groups on the surface of Ti3 C2 Tx , severely degrading its properties and posing a threat to the performance of electron transfer among electrical devices. Herein, a supercritical carbon dioxide-based ternary solution (scCO2 /DMSO/HCl) to produce fluoride-free Ti3 C2 Tx in mild conditions (via 0.5 m HCl, 20 MPa, 32 °C) is reported. The fluorine-free Ti3 C2 Tx films electrode presents an excellent gravimetric capacitance of 320 F g-1 at 2 mV s-1 in 1 m H2 SO4 . Besides, it is demonstrated that fluorine-free Ti3 C2 Tx films exhibit outstanding EMI shielding efficiency of 53.12 dB at 2.5 µm thickness. The findings offer a mild and practical approach to producing fluoride-free Ti3 C2 Tx and open opportunities for exploring MXenes' potential applications in various fields.

2.
Mol Pharm ; 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39378327

RESUMEN

Despite the advancements in cancer therapy, delivering active pharmaceutical ingredients (APIs) using nanoparticles remains challenging due to the failed conveyance of the required drug payload, poor targeting ability, and poor biodistribution, hampering their clinical translation. Recently, the appropriate design of materials with intrinsic therapeutic functionalities has garnered enormous interest in the development of various intelligent therapeutic nanoplatforms. In this study, we demonstrate the fabrication of transition metal (molybdenum, Mo)-doped manganese dioxide (MnO2) nanoarchitectures, exhibiting diagnostic (magnetic resonance imaging, MRI) and therapeutic (chemodynamic therapy, CDT) functionalities. The facile hydrothermal approach-assisted Mo-doped MnO2 flower-like nanostructures offered tailorable morphologies in altered dimensions, precise therapeutic effects, exceptional biocompatibility, and biodegradability in the tumor microenvironment. The resultant defects due to doped Mo species exhibited peroxidase and oxidase activities, improving glutathione (GSH) oxidation. The two sets of variable valence metal ion pairs (Mn2+/Mn4+ and Mo5+/Mo6+) and their interplay could substantially improve the Fenton-like reaction and generate toxic hydroxyl radicals (•OH), thus achieving CDT-assisted antitumor effects. As inherent T1-MRI agents, these MnO2 nanoparticles displayed excellent MRI efficacy in vitro. Together, we believe that these conformational Mo-doped MnO2 nanoarchitectures with two pairs of variable valence states could potentiate drugless therapy in pharmaceutics.

3.
Langmuir ; 40(26): 13550-13561, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38902967

RESUMEN

There has been a growing emphasis on facile preparation of binary heterogeneous composite materials. Leveraging the eco-friendly efficiency of supercritical CO2 technology, we achieved precise control over the influencing factors of mass transfer, enabling the accurate modulation of the resulting product morphology and properties. In the current study, CuxO/ZrOy composite materials were prepared using this technology and calcined to obtain electrode materials for the detection of cysteine (Cys). Essential comprehensive characterization techniques were employed to elucidate the heterojunction. The resulting electrode demonstrated a linear response to Cys within a concentration range of 0.5 nM to 1 µM, featuring a high sensitivity of 1035 µA·cm-2·µM-1 and a low detection limit of 97.3 nM. Thus, establishing a novel avenue for nonenzyme-based electrochemical sensors tailored for biologically active Cys detection through the implementation of a heterogeneous structure.

4.
Am J Geriatr Psychiatry ; 32(7): 856-866, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38383225

RESUMEN

BACKGROUND: Mental disorders and cognitive impairment are common in older patients with arthritis. While it is recognized that mental conditions may play a role in the connection between arthritis and cognitive impairment, the precise underlying relationship remains uncertain. METHODS: The data was derived from the baseline survey of the Guangdong Mental Health Survey in South China, involving a sample of 3,764 citizens aged 65 and older. An array of aspects were explored, including socio-demographics, lifestyle behaviors, self-reported chronic conditions, depression, anxiety, and cognitive impairment. Logistic regression analyses examined the association between arthritis and cognitive impairment after adjustment for potential confounders. Serial mediation models were used to examine whether depression or anxiety played a mediating role in the arthritis-cognitive impairment linkage. RESULTS: The prevalence rates of cognitive impairment and arthritis of the older adults were 28.9% and 12.1%, respectively. Compared to those without arthritis, participants with arthritis were at a higher risk of cognitive impairment (OR = 1.322, 95%CI: 1.022-1.709) after adjustment for socio-demographics, lifestyle behaviors, and mental health conditions. Serial mediation analyses indicated that depressive and anxiety symptoms co-played a serial mediating role in the association between arthritis and cognitive impairment (B1 = 0.025, 95%CI: 0.005-0.052; B2 = 0.050, 95%CI: 0.021-0.086). CONCLUSIONS: Arthritis may heighten cognitive impairment risk in Chinese older adults, and the relationship was potentially mediated by depressive and anxiety symptoms. Future interventions should be considered, integrating mental health assessments into arthritis care frameworks and being alert to possible cognitive impairment.


Asunto(s)
Ansiedad , Artritis , Disfunción Cognitiva , Depresión , Humanos , Anciano , Masculino , Femenino , China/epidemiología , Disfunción Cognitiva/epidemiología , Artritis/epidemiología , Ansiedad/epidemiología , Depresión/epidemiología , Prevalencia , Anciano de 80 o más Años , Comorbilidad , Encuestas Epidemiológicas , Pueblos del Este de Asia
5.
Inorg Chem ; 63(1): 661-667, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38131323

RESUMEN

Enhancing anisotropy through an effective synergistic arrangement of anionic and cationic groups is crucial for improving the birefringence optical properties of materials. In this work, by transforming I-O into I-F through the fluorination strategy, two metal-free guanidine fluorooxoiodates (C(NH2)3)2(I2O5F)(IO3)(H2O) and C(NH2)3IO2F2 and one guanidine iodate C(NH2)3IO3 were successfully synthesized using the hydrothermal method. An unprecedented dimer [I2O5F] formed by [IO3F] and [IO3] in (C(NH2)3)2(I2O5F)(IO3)(H2O) was found, which greatly enriches the structural diversity of fluorooxoiodates. All three compounds feature a relatively large birefringence (Δn = 0.068, 0.110 and 0.075 at 546 nm) and a short ultraviolet cutoff edge. The theoretical calculation was carried out to understand the electronic structures and linear optical properties.

6.
BMC Psychiatry ; 24(1): 86, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297269

RESUMEN

INTRODUCTION: Much confusion exists between health-related QoL (HRQoL) scales and subjective QoL (SQoL) scales. One method to avoid confusion is use of a single question that asks What is your quality of life? or similar. This study explored the relationship between biopsychosocial factors and high SQoL, SQoL stability, and factors associated with improving SQoL. METHOD: We conducted a large cohort study of community-dwelling Chinese adults with schizophrenia, with two data points (2015-2016 (N = 742), 2017-2018 (N = 491)). Demographic and clinically related items and a comprehensive suite of published measures were collected. Direct logistic regressions were used to explore links between biopsychosocial factors and high SQoL and Improvement in SQoL across time. RESULTS: Sample at Baseline: Male = 62.3%; Med age = 38.5 years; Med Age at illness onset = 24 years; SQoL Mode = neither poor nor good. Three independent variables predicted high SQoL at T1. Contemporary age and the presence of clinically relevant symptoms had a negative relationship with high SQoL; insight had a positive relationship with high SQoL. SQoL changed significantly across time with a modest effect size. Age at illness onset was the single independent variable linked to improving SQoL favoring being older at the time of illness onset. DISCUSSION/CONCLUSIONS: SQoL can be high and changeable. While symptomology and illness insight may affect SQoL self-appraisals at single points in time, only age of illness onset was connected with improving SQoL. Thus, public health measures to delay illness onset are important. In addition, care about the distinction between HRQoL and SQoL in study design and choice of measures is necessary and will depend on the purpose and context.


Asunto(s)
Esquizofrenia , Adulto , Humanos , Masculino , Adulto Joven , Esquizofrenia/diagnóstico , Calidad de Vida/psicología , Estudios de Cohortes , Vida Independiente , Atención Primaria de Salud
7.
BMC Public Health ; 24(1): 2721, 2024 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-39370527

RESUMEN

BACKGROUND: Mental health literacy is a predictor of health outcomes in psychological distress. However, limited research has explored whether low mental health literacy is associated with recent depression and anxiety. METHODS: We used data from the Guangdong Mental Health Survey, a provincial representative and a population-based survey with a multistage stratified cluster random sampling method. We included adults aged 18 and above living in communities from September to December 2021 in Guangdong, China. Eligible participants were those who completed the mental health literacy questionnaire and assessments for depression and anxiety symptoms. We assessed the proportion of individuals with low mental health literacy by categories of psychological symptoms and whether low mental health literacy was associated with depressive and anxiety symptoms in the general population and subgroups. RESULTS: A total of 16,715 adults were included. We found that individuals with more severe symptoms had a greater proportion of low mental health literacy- it went from 89.4% in participants without depression or anxiety to 96.2% in people who co-occurred with depression and anxiety (x2 = 21.457, P < 0.001). After controlling confounders, low mental health literacy was associated with depression (adjusted Odds Ratio, aOR [95%CI]:2.74 [1.92-4.04]) and anxiety (2.27 [1.49-3.64]) in the total sample, when compared with adequate mental health literacy. CONCLUSIONS: This study found a positive association between low mental health literacy and the presence of depression and anxiety. Tackling inadequate mental health literacy may be a key strategy to promote psychological well-being across the lifespan, especially for young adults.


Asunto(s)
Ansiedad , Depresión , Alfabetización en Salud , Salud Mental , Humanos , Alfabetización en Salud/estadística & datos numéricos , China/epidemiología , Femenino , Masculino , Adulto , Depresión/epidemiología , Depresión/psicología , Persona de Mediana Edad , Ansiedad/epidemiología , Ansiedad/psicología , Adulto Joven , Adolescente , Salud Mental/estadística & datos numéricos , Encuestas Epidemiológicas , Anciano
8.
BMC Public Health ; 24(1): 1769, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961390

RESUMEN

BACKGROUND: This study aimed to assess the public knowledge regarding Alzheimer's Disease (AD) in Zhuhai, China, focusing on identifying knowledge gaps and the influence of demographic and health factors. METHODS: A cross-sectional study was conducted in Zhuhai, China, from October to November 2022. A total of 1986 residents from 18 communities were selected employing stratified multi-stage equi-proportional sampling. Questionnaires covering general information and the Alzheimer's Disease Knowledge Scale (ADKS) were investigated face-to-face. Ordinal multiclass logistic regression was applied to assess the relationship between AD awareness and demographic and health characteristics. RESULTS: The average ADKS score was 18.5 (SD = 3.36) in Zhuhai. The lowest awareness rates were observed in the "Symptoms" and "Caregiving" subdomains of ADKS, with rates of 51.01% and 43.78%, respectively. The correct rates for the 30 ADKS questions ranged from 16.62 to 92.6%, showing a bimodal pattern with clusters around 80% and 20%. Women (OR = 1.203, 95% CI: 1.009-1.435), individuals aged 60 years or older (OR = 2.073, 95% CI: 1.467-2.932), those living in urban areas (OR = 1.361, 95% CI: 1.117-1.662), higher average monthly household income per capita (OR = 1.641, 95% CI: 1.297-2.082), and without any neurological or mental disorders (OR = 1.810, 95% CI: 1.323-2.478) were more likely to have higher levels of awareness about Alzheimer's disease. CONCLUSIONS: Adults in Zhuhai show a limited knowledge of AD, particularly in the 'Symptoms' and 'Caregiving' subdomains. Upcoming health campaigns must focus on bridging the knowledge gaps in different subdomains of AD, especially among subgroups with lower awareness, as identified in our study.


Asunto(s)
Enfermedad de Alzheimer , Conocimientos, Actitudes y Práctica en Salud , Humanos , Estudios Transversales , China/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Adulto , Encuestas y Cuestionarios , Adulto Joven
9.
Sensors (Basel) ; 24(8)2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38676067

RESUMEN

Facial expression is an important way to reflect human emotions and it represents a dynamic deformation process. Analyzing facial movements is an effective means of understanding expressions. However, there is currently a lack of methods capable of analyzing the dynamic details of full-field deformation in expressions. In this paper, in order to enable effective dynamic analysis of expressions, a classic optical measuring method called stereo digital image correlation (stereo-DIC or 3D-DIC) is employed to analyze the deformation fields of facial expressions. The forming processes of six basic facial expressions of certain experimental subjects are analyzed through the displacement and strain fields calculated by 3D-DIC. The displacement fields of each expression exhibit strong consistency with the action units (AUs) defined by the classical Facial Action Coding System (FACS). Moreover, it is shown that the gradient of the displacement, i.e., the strain fields, offers special advantages in characterizing facial expressions due to their localized nature, effectively sensing the nuanced dynamics of facial movements. By processing extensive data, this study demonstrates two featured regions in six basic expressions, one where deformation begins and the other where deformation is most severe. Based on these two regions, the temporal evolutions of the six basic expressions are discussed. The presented investigations demonstrate the superior performance of 3D-DIC in the quantitative analysis of facial expressions. The proposed analytical strategy might have potential value in objectively characterizing human expressions based on quantitative measurement.


Asunto(s)
Expresión Facial , Imagenología Tridimensional , Humanos , Imagenología Tridimensional/métodos , Cara/fisiología , Emociones/fisiología , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos
10.
J Sci Food Agric ; 104(11): 6626-6639, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-38523343

RESUMEN

BACKGROUND: Optimizing biochar application is vital for enhancing crop production and ensuring sustainable agricultural production. A 3-year field experiment was established to explore the effects of varying the biochar application rate (BAR) on crop growth, quality, productivity and yields. BAR was set at 0, 10, 50 and 100 t ha-1 in 2018; 0, 10, 25, 50 and 100 t ha-1 in 2019; and 0, 10, 25 and 30 t ha-1 in 2020. Crop quality and growth status and production were evaluated using the dynamic technique for order preference by similarity to ideal solution with the entropy weighted method (DTOPSIS-EW), principal component analysis (PCA), membership function analysis (MFA), gray relation analysis (GRA) and the fuzzy Borda combination evaluation method. RESULTS: Low-dose BAR (≤ 25 t ha-1 for cotton; ≤ 50 t ha-1 for sugar beet) effectively increased biomass, plant height, leaf area index (LAI), water and fertility (N, P and K) productivities, and yield. Biochar application increased the salt absorption and sugar content in sugar beet, with the most notable increases being 116.45% and 20.35%, respectively. Conversely, BAR had no significant effect on cotton fiber quality. The GRA method was the most appropriate for assessing crop growth and quality. The most indicative parameters for reflecting cotton and sugarbeet growth and quality status were biomass and LAI. The 10 t ha-1 BAR consistently produced the highest scores and was the most economically viable option, as evaluated by DTOPSIS-EW. CONCLUSION: The optimal biochar application strategy for improving cotton and sugar beet cultivation in Xinjiang, China, is 10 t ha-1 biochar applied continuously. © 2024 Society of Chemical Industry.


Asunto(s)
Beta vulgaris , Carbón Orgánico , Producción de Cultivos , Fertilizantes , Gossypium , Beta vulgaris/química , Beta vulgaris/crecimiento & desarrollo , Carbón Orgánico/química , Gossypium/crecimiento & desarrollo , Gossypium/metabolismo , China , Producción de Cultivos/métodos , Fertilizantes/análisis , Biomasa
11.
J Am Chem Soc ; 145(23): 12884-12893, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37249907

RESUMEN

Lignin is the most abundant aromatic polymer from the natural and renewable lignocellulosic biomass resource. Developing highly efficient catalysts for lignin depolymerization to produce valuable monophenols with high yield and selectivity remains a desirable but challenging target in this field. Here, we design a synergistic catalyst combining atomically dispersed Mo centers and Al Lewis acid sites on a MgO substrate (Mo1Al/MgO) for the depolymerization of Eucalyptus lignin via the ß-aryl ether bond cleavage. A near-theoretical monophenol yield of 46% with an ultrahigh selectivity of 92% for coniferyl and sinapyl methyl ether, as well as good cycling durability, was achieved simultaneously by Mo1Al/MgO in an inert N2 atmosphere. First-principles calculations and control catalytic experiments confirmed the synergistic catalysis mechanism between Mo1-O5 single-atom centers and the neighboring Al Lewis acid sites with the participation of a methanol solvent. This study validates the feasibility of designing better-performing catalysts with synergistic multiactive sites for the efficient and selective disassembly of complex renewable biopolymers into highly value-added products with lower cost and greater security.

12.
Opt Express ; 31(1): 555-563, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36606991

RESUMEN

This paper presents a method to measure the three-dimensional distribution of uniaxial stress based on Terahertz Time Domain Spectroscopy (THz-TDS). The measurement principle was first established, which combines the computed tomography (CT) method and the photo-elastic effects. A classic filtered back-projection algorithm is adopted to calculate the three-dimensional stress fields from THz-TDS scanning images. Then, in verification experiment, the uniaxial stress distribution in the compressed cylinder and the stretched screw is obtained based on the measurement principle. Finally, the reliability of the proposed method has been verified by comparing the experiment results with the finite element simulation. A reasonable agreement is obtained.

13.
Int J Geriatr Psychiatry ; 38(6): e5956, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37329227

RESUMEN

OBJECTIVES: Subjective cognitive complaints (SCC) are the earliest symptom of Alzheimer's disease (AD) progression. Increasing evidence shows an association between poor sleep quality and SCC, but the current conclusions regarding the association between poor sleep quality and SCC in older adults are contradictory. Here, we aimed to explore the correlation of SCC with poor sleep quality among older adults without dementia living in nursing home and community in China. METHODS: A cross-sectional survey on sleep and psychosomatic health of older adults was conducted in Guangdong, China, between November 2020 and March 2021. Socio-demographic, health-related information, psychological factors, sleep quality and SCC of participants were evaluated through a face-to-face interview. A 9-item Subjective Cognitive Decline Questionnaire (SCD-Q9) was used to measure SCC; SCD-Q9 > 3 was defined as SCC. The Chinese version of the Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality; PSQI > 7 was defined as poor sleep quality. The relationship between SCC and sleep quality was evaluated using logistics regression analysis. RESULTS: The study involved 730 participants (mean age 74.14 ± 8.246 years). The total SCC prevalence was 59.59%. The SCC group had poor sleep quality than the reference group (p < 0.05). Adjusted multiple logistic regression analysis revealed an association of poor sleep quality with SCC (OR = 1.841; 95% CI, 1.267-2.647; p = 0.001) after controlling for age, sex, residence, education level, marital status, income, smoking, alcohol consumption, tea drinking, multimorbidity, waist circumference, napping duration, anxiety symptoms, and depression symptoms. Hierarchical logistics regression analysis showed an association between sleep quality and SCC among community older adults (OR = 2.872; 95% CI: 1.787-4.615; p < 0.001), but not in nursing home residents (OR = 0.845; 95% CI: 0.437-1.637; p = 0.619). CONCLUSIONS: Poor sleep quality is associated with SCC in community older adults. Therefore, medical staff should take measures, such as earlier cognitive intervention, to postpone cognitive decline in older adults, in the meantime, earlier management and treatment of sleep disorders should be taken into consideration.


Asunto(s)
Disfunción Cognitiva , Trastornos del Inicio y del Mantenimiento del Sueño , Trastornos del Sueño-Vigilia , Humanos , Anciano , Anciano de 80 o más Años , Estudios Transversales , Calidad del Sueño , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/complicaciones , Sueño , Trastornos del Sueño-Vigilia/epidemiología , Cognición
14.
Angew Chem Int Ed Engl ; 62(30): e202306553, 2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37227067

RESUMEN

Replacing the oxygen evolution reaction (OER) with the thermodynamically favorable electrooxidation of organics is considered a promising approach for the simultaneous production of hydrogen (H2 ) and high-value chemicals. However, exploring and optimizing efficient electrocatalysts remains a challenge for large-scale production of value-added steroid carbonyl and H2 . Herein, Cr-NiO/GF and Cr-Ni3 N/GF (GF: graphite felt) electrocatalysts were designed as anode and cathode for the production of steroid carbonyls and H2 , respectively. The cooperative Cr-NiO and ACT (4-acetamido-2,2,6,6-tetramethyl-1-piperidine-N-oxyl) electrocatalyst can be extended to the electrooxidation of a series of steroid alcohols to the corresponding aldehydes. Additionally, Cr-Ni3 N displays superior electrocatalytic activity for hydrogen evolution reaction (HER), with a low overpotential of 35 mV to deliver 10 mA cm-2 . Furthermore, the system coupled with anodic electrooxidation of sterol and cathodic HER exhibited excellent performance with high space-time yield of 48.85 kg m-3 h-1 for steroid carbonyl and 1.82 L h-1 for H2 generation in a two-layer stacked flow cell. Density Functional Theory (DFT) calculations indicated that Cr doping effectively stabilizes ACTH on the NiO surface, and ACTH molecule could be captured via the ketonic oxygen interaction with Cr, resulting in excellent electrocatalytic activity. This work develops a novel approach to the rational design of efficient electrocatalysts for the simultaneous production of H2 and large-scale value-added pharmaceutical carbonyl intermediates.

15.
Angew Chem Int Ed Engl ; 62(15): e202218664, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36787047

RESUMEN

Using sunlight to produce valuable chemicals and fuels from carbon dioxide (CO2 ), i.e., artificial photosynthesis (AP) is a promising strategy to achieve solar energy storage and a negative carbon cycle. However, selective synthesis of C2 compounds with a high CO2 conversion rate remains challenging for current AP technologies. We performed CO2 photoelectroreduction over a graphene/silicon carbide (SiC) catalyst under simulated solar irradiation with ethanol (C2 H5 OH) selectivity of>99 % and a CO2 conversion rate of up to 17.1 mmol gcat -1 h-1 with sustained performance. Experimental and theoretical investigations indicated an optimal interfacial layer to facilitate the transfer of photogenerated electrons from the SiC substrate to the few-layer graphene overlayer, which also favored an efficient CO2 to C2 H5 OH conversion pathway.

16.
Opt Express ; 30(26): 46193-46208, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36558579

RESUMEN

Picosecond ultrasonics (PU), time-domain Brillouin scattering (TDBS), and time-domain thermo-reflectance (TDTR) are all in-situ, non-destructive, and non-contact experimental techniques based on the ultrafast laser pump-probe method, which can generate and detect coherent acoustic phonons (CAP) and thermal transport in thin metal film-glass substrate system. However, these techniques are generally considered different experimental methods to characterize the thermal or mechanical properties of metal nano-objects or transparent materials. Here we present a comprehensive characterization of the generation, propagation, and attenuation of high-frequency CAP and cross-plane thermal transport in the thin Cr film-glass substrate system by PU, TDBS, and TDTR. To investigate the key factors of characterizations, two kinds of thin Cr film-glass substrate systems were measured on the film side and substrate side. The measured thermal and mechanical properties show that boundary conditions and film thickness have significantly affected the characterization.

17.
Nanotechnology ; 33(26)2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35313291

RESUMEN

Highly efficient and inexpensive electrocatalysts for oxygen evolution reaction (OER) are extensively studied for water splitting. Herein, a unique bimetallic nanocomposite CoNi(OH)2@NiCo2S4nanosheet arrays derived from metal-organic-frameworks (MOFs, CoNi-ZIF) is simply fabricated on Ni foam, endowing large specific surface area and outstanding electrical conductivity. Compared with their single-metallic counterparts, the bimetallic composite displays dramatically low overpotential and small Tafel slope as well as outstanding catalytic stability. The overpoptential at 20 mA cm-2for CoNi(OH)2@NiCo2S4is only 230 mV in comparison with Ni(OH)2@Ni3S2(266 mV), Co(OH)2@Co3S4(294 mV) and RuO2(η = 302 mV). First-principle calculations based on density functional theory (DFT) are carried out and reveal that the introduction of Ni in Co(OH)2helps lowered the energy difference of ΔGOOH*-ΔGO*, and thereby boosting the OER reactivity. This study provides an effective approach for the rational construction of low-cost metal hybrids.

18.
Philos Trans A Math Phys Eng Sci ; 380(2234): 20210318, 2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-36031833

RESUMEN

When a rubber tube with free ends is inflated under volume control, the pressure will first reach a maximum and then decrease monotonically to approach a constant asymptote. The pressure maximum corresponds to the initiation of a localized bulge and is predicted by a bifurcation condition, whereas the asymptote is the Maxwell pressure corresponding to a 'two-phase' propagation state. By contrast, when the tube is first pre-stretched and then has its ends fixed during subsequent inflation, the pressure as a function of the bulge amplitude has both a maximum and a minimum, and the behaviour on the right ascending branch has previously not been fully understood. We show that for all values of the pre-stretch and tube length, the ascending branches all converge to a single curve that is dependent only on the ratio of the tube thickness to the outer radius. This curve represents the Maxwell state to be approached in each case (if Euler buckling or axisymmetric wrinkling does not occur first), but this state is pressure-dependent, in contrast to the free-ends case. We also demonstrate experimentally that localized bulging cannot occur when the pre-stretch is sufficiently large and investigate what strain-energy functions can predict this observed phenomenon. This article is part of the theme issue 'The Ogden model of rubber mechanics: Fifty years of impact on nonlinear elasticity'.

19.
BMC Psychiatry ; 22(1): 147, 2022 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-35209875

RESUMEN

BACKGROUND: Subjective cognitive decline (SCD) may be the early screening signal to distinguish susceptible population with Alzheimer's disease (AD) and mild cognitive impairment (MCI). Subjective cognitive complaints (SCCs) have been proved strongly associated with SCD. This study aimed to explore the association between sleep duration and SCCs in the Chinese elderly. METHODS: We conducted a cross-sectional study involving 688 participants aged 60 years and older in Guangdong Province, China. SCCs were assessed by the Subjective Cognitive Decline questionnaire 9 (SCD-Q9), which contained 9 items with two dimensions, including the overall memory function and time comparison (OMTC) and daily activity ability (DAA). Restricted cubic splines and generalized additive model (GAM) were used to fit the association between sleep duration and SCD-Q9 score. RESULTS: There were significant U-shaped associations between sleep duration and overall score of SCD-Q9 (EDF = 3.842, P < 0.001), as well as the OMTC dimension (EDF = 4.471, P < 0.001) in the age- and gender-adjusted GAM. The lowest points on the overall score of SCD-Q9 and OMTC score were observed in those sleeping 8 h per night. After further adjusting for other demographic characteristics, lifestyle behaviors, hypertension and diabetes, the U-shaped associations between sleep duration and the overall score of SCD-Q9 (EDF = 3.575, P = 0.004), sleep duration and the OMTC score (EDF = 4.478, P = 0.010) were still found. The daily activity ability (DAA) score was also non-linear associated with sleep duration both in the age- and gender-adjusted GAM (EDF = 2.314, P < 0.001) and further adjusted GAM (EDF = 2.080, P = 0.010). CONCLUSIONS: Both longer sleep duration (> 8 h) and shorter duration (< 8 h) were linked to worse SCCs. Future studies should explore the protective effect of managing sleep duration on SCD and its progression to dementia.


Asunto(s)
Disfunción Cognitiva , Anciano , China/epidemiología , Cognición , Disfunción Cognitiva/psicología , Estudios Transversales , Humanos , Persona de Mediana Edad , Pruebas Neuropsicológicas , Sueño
20.
J Chem Phys ; 157(18): 184105, 2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36379779

RESUMEN

Revealing the effect of external applied potential on the reaction mechanism and product selectivity is of great significance in electrochemical studies. In this work, the grand canonical density functional theory method was applied to simulate the explicit electrocatalytic process of oxygen evolution reaction and electrochemical ozone production due to the O3 product sensitivity toward the applied potential. Over the Pt/Pd single atom embedded on B/N co-doped graphene (Pt/Pd-BNC) surface, crossover points of O2/O3 selectivity inversion were predicted to be 1.33 and 0.89 V vs standard hydrogen electrode, which were also consistent with the previous experimental results. An in-depth analysis of the energetic terms in the reaction free energies also found the considerable impact of the applied potential on the Helmholtz free energy term, with optimal potential predicted for the key elementary steps, and linear correlations between electrode potential (U) and reaction free energy were found for each elementary step. This study offers extensive knowledge on the potential effect on the O2/O3 selective formation on two-dimensional anode surfaces and provides new insights for investigating the reactivity/selectivity on electrode surfaces in real reaction conditions.

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