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1.
J Chem Theory Comput ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264121

RESUMO

Nanoengineered metal@zeolite materials have recently emerged as a promising class of catalysts for several industrially relevant reactions. These materials, which consist of small transition metal nanoclusters confined within three-dimensional zeolite pores, are interesting because they show higher stability and better sintering resistance under reaction conditions. While several such hybrid catalysts have been reported experimentally, key questions such as the impact of the zeolite frameworks on the properties of the metal clusters are not well understood. To address such knowledge gaps, in this study, we report a robust and transferable machine learning-based potential (MLP) that is capable of describing the structure, stability, and dynamics of zeolite-confined gold nanoclusters. Specifically, we show that the resulting MLP maintains ab initio accuracy across a range of temperatures (300-1000 K) and can be used to investigate time scales (>10 ns), length scales (ca. 10,000 atoms), and phenomena (e.g., ensemble-averaged stability and diffusivity) that are typically inaccessible using density functional theory (DFT). Taken together, this study represents an important step in enabling the rational theory-guided design of metal@zeolite catalysts.

2.
Chem Sci ; 15(30): 11761-11774, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39092104

RESUMO

Electron-deficient heteroarenes based on dithienopyrrolobenzothiadiazole (BTP) have been highly attractive due to their fascinating packing structures, broad absorption profiles, and promising applications in non-fullerene organic solar cells. However, the control of their crystal structures for superior charge transport still faces big challenges. Herein, a conformation engineering strategy is proposed to rationally manipulate the single crystal structure of BTP-series heteroarenes. The parent molecule BTPO-c has a 3D network crystal structure, which originates from its banana-shaped conformation. Subtracting one thiophene moiety from the central backbone leads to a looser brickwork crystal structure of the derivative BTPO-z because of its interrupted angular-shaped conformation. Further subtracting two thiophene moieties results in the derivative BTPO-l with a compact 2D-brickwork crystal structure due to its quasi-linear conformation with a unique dimer packing structure and short π-π stacking distance (3.30 Å). Further investigation of charge-transport properties via single-crystal organic transistors demonstrates that the compact 2D-brickwork crystal structure of BTPO-l leads to an excellent electron mobility of 3.5 cm2 V-1 s-1, much higher than that of BTPO-c with a 3D network (1.9 cm2 V-1 s-1) and BTPO-z with a looser brickwork structure (0.6 cm2 V-1 s-1). Notably, this study presents, for the first time, an elegant demonstration of the tunable single crystal structures of electron-deficient heteroarenes for efficient organic electronics.

3.
Heliyon ; 10(13): e33725, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39071563

RESUMO

Digital green innovation (DGI) is crucial for high-pollution enterprises to improve green performance. However, there is a paradox regarding the impact of environmental regulations on DGI, primarily due to the varied effects of diverse regulatory tools. To resolve this paradox, based on Neoclassical Economics and the Porter Hypothesis, we empirically examine the influence of heterogeneous environmental regulations on DGI using a sample of high-pollution enterprises in China. The conclusions indicate that environmental protection tax has a pushing-forward effect on DGI, while environmental protection subsidy has a crowding-out effect. Moreover, enterprises' resource base and technological innovation capability positively moderate the impact of environmental protection tax. External pressure, internal incentives, pandering to governments, and managerial opportunism have mediating effects. Our research offers a new perspective to resolve the paradox of the effect of environmental regulations on DGI, explores potential mechanism as well as boundary condition, and proposes a new way of measuring DGI of enterprises with patents. Accordingly, we offer valuable policy recommendations about the formulation of environmental regulations, the facilitation of DGI, and the advancement of China's ecological civilization.

4.
J Ultrasound Med ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943425

RESUMO

OBJECTIVE: To determine the diagnostic and therapeutic value of contrast-enhanced ultrasound-guided endoscopic retrograde appendicitis treatment (ERAT) in patients with uncomplicated appendicitis. METHODS: A retrospective analysis was performed on clinical and ultrasound data collected from 105 pediatric patients with uncomplicated appendicitis between January 2020 and December 2023. The ultrasound findings before and after treatment, as well as postoperative follow-up and recurrence rates, were summarized and analyzed. RESULTS: Successful intubation was achieved in 96 patients (91.4%). The conventional ultrasound appendix visualization rate was 39.6% (38/105), while the appendix visualization rate after contrast-enhanced ultrasound-guidance was 75% (72/105). Contrast-enhanced ultrasound revealed various appendiceal morphologic changes in 89 patients, such as twisting, tortuosity, stiffness, rough inner wall, dilated diameter, and narrowing of the lumen. Additionally, local filling defects, which indicated the presence of fecal stones or debris deposition, were noted in 68 patients. No leakage of the contrast agent occurred. Post-treatment evaluation showed improvement in appendiceal diameter, lumen, and filling defects (P < .01). The follow-up rate was 82 of 89 patients (92.1%), all of whom recovered well without a recurrence. The recurrence rate was 7.9% (7/89). Among the patients with recurrences, five patients resolved after medical treatment and two patients recovered after surgical treatment. CONCLUSION: Contrast-enhanced ultrasound-guided ERAT for uncomplicated appendicitis is safe and effective. Specifically, the appendix is increased, which facilitates an evaluation of therapeutic effectiveness. ERAT serves as a valuable supplementary modality to determine the need for surgical treatment of acute appendicitis, which is of significant clinical value.

5.
EClinicalMedicine ; 71: 102583, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38618201

RESUMO

Background: Exposure to multiple risk factors is prevalent in low-and middle-income countries (LMICs), challenging one-directional strategies to address preventable under-5 mortality (U5M). This study aims to assess the associations between concurrence of multiple risk factors and U5M in LMICs. Methods: We extracted data from the Demographic and Health Surveys conducted between 2010 and 2021 across 61 LMICs. Our primary outcome was U5M, defined as deaths from birth to 59 months. Binary logistic regression model was applied to ascertain the association between U5M and a total of 20 critical risk factors. Upon identifying the risk factors demonstrating the strongest associations, we investigated the simultaneous presence of multiple risk factors in each individual and assessed their combined effects on U5M with logistic regression models. Findings: Of the 604,372 under-5 children, 18,166 (3.0%) died at the time of the survey. Unsatisfied family planning needs was the strongest risk factor for U5M (odds ratio [OR]: 2.0, 95% confidence interval [CI]: 1.9-2.1), followed by short birth interval (<18 months; OR: 2.0, 95% CI: 1.9-2.1), small birth size (OR: 2.0, 95% CI: 1.8-2.1), never breastfed or delayed breastfeeding (OR: 2.0, 95% CI: 1.9-2.0), and low maternal education (OR: 1.6, 95% CI: 1.4-1.8). 66.7% (66.6%-66.8%) of the children had 2 or more leading risk factors simultaneously. Simultaneous presence of multiple leading risk factors was significantly associated with elevated risk of U5M and children presenting with all 5 leading risk factors exhibited an exceedingly high risk of U5M (OR: 5.2, 95% CI: 4.3-6.3); a dose-response relationship between the number of risk factors and U5M was also observed-with the increment of numbers of leading risk factors, the U5M showed an increasing trend (p-trend < 0.001). Interpretation: Exposure to multiple risk factors is very common in LMICs and underscores the necessity of developing multisectoral and integrated approaches to accelerate progress in reducing U5M in line with the SDG 3.2. Funding: This research is funded by Research Fund, Vanke School of Public Health, Tsinghua University.

6.
BMC Med ; 22(1): 54, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317131

RESUMO

BACKGROUND: The appropriateness of hypertension thresholds for triggering action to prevent cardiovascular and renal complications among non-White populations in the UK is subject to question. Our objective was to establish ethnicity-specific systolic blood pressure (SBP) cutoffs for ethnic minority populations and assess the efficacy of these ethnicity-specific cutoffs in predicting adverse outcomes. METHODS: We analyzed data from UK Biobank, which included 444,418 participants from White, South Asian, Black Caribbean, and Black African populations with no history of cardiorenal complications. We fitted Poisson regression models with continuous SBP and ethnic groups, using Whites as the referent category, for the composite outcome of atherosclerotic cardiovascular disease, heart failure, and chronic kidney disease. We determined ethnicity-specific thresholds equivalent to the risks observed in Whites at SBP levels of 120, 130, and 140 mm Hg. We adjusted models for clinical characteristics, sociodemographic factors, and behavioral factors. The performance of ethnicity-specific thresholds for predicting adverse outcomes and associated population-attributable fraction (PAF) was assessed in ethnic minority groups. RESULTS: After a median follow-up of 12.5 years (interquartile range, 11.7-13.2), 32,662 (7.4%) participants had incident composite outcomes. At any given SBP, the predicted incidence rate of the composite outcome was the highest for South Asians, followed by White, Black Caribbean, and Black African. For an equivalent risk of outcomes observed in the White population at an SBP level of 140 mm Hg, the SBP threshold was lower for South Asians (123 mm Hg) and higher for Black Caribbean (156 mm Hg) and Black African (165 mm Hg). Furthermore, hypertension defined by ethnicity-specific thresholds was a stronger predictor and resulted in a larger PAF for composite outcomes in South Asians (21.5% [95% CI, 2.4,36.9] vs. 11.3% [95% CI, 2.6,19.1]) and Black Africans (7.1% [95% CI, 0.2,14.0] vs. 5.7 [95% CI, -16.2,23.5]) compared to hypertension defined by guideline-recommended thresholds. CONCLUSIONS: Guideline-recommended blood pressure thresholds may overestimate risks for the Black population and underestimate risks for South Asians. Using ethnicity-specific SBP thresholds may improve risk estimation and optimize hypertension management toward the goal of eliminating ethnic disparities in cardiorenal complications.


Assuntos
Etnicidade , Hipertensão , Humanos , Estudos Prospectivos , Pressão Sanguínea , Biobanco do Reino Unido , Bancos de Espécimes Biológicos , Grupos Minoritários , Hipertensão/epidemiologia , Fatores de Risco
7.
J Glob Health ; 14: 04026, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334279

RESUMO

Background: Prolonged exclusive breastfeeding (PEB) for children older than six months old is a threat to appropriate complementary feeding practices. This study aims to examine the trend of PEB among children aged 6-23 months in India. Methods: We adopted five waves of National Family Health Survey (NFHS) data between 1992-93 and 2019-21. PEB was defined as children aged six months and above currently consuming breastmilk as the only source of energy, protein and micronutrients. We generated descriptive statistics and a series of multivariable logistic regressions to estimate the prevalence and trend in the PEB rate. Moreover, we assessed how child age and socioeconomic factors (i.e. child gender and age, place of residence, household wealth, and maternal education) were related with PEB using mutually and single-adjusted model. Results: There were 184 891 Indian children aged 6-23 months old included in this study with 48.0% being female. We found that the proportion of PEB increased from 4.3% in 1992 to 7.7% in 2021, of which the rate for children aged six-eight months rose from 14.0 to 20.1%. Our results showed that children who were from poorer households or with lower-educated mothers were more likely to experience prolonged exclusive breastfed. Take the year of 2019-21 as an example, compared to the households of the richest quintile, children from households of the poorer quintile were significantly more likely to experience PEB, with odds ratio (OR) of 1.33 (95% confidence interval (CI) = 1.09-1.61). Moreover, children with illiterate mothers had 21% higher odds of having prolonged exclusively breastfeeding (OR = 1.21; 95% CI = 1.01-1.44) compared with children with mothers who have college and above education. Conclusions: PEB among children over six months old is prevalent in India, particularly among children from disadvantaged households. Poverty reduction and maternal education are of great potential importance for policymakers to promote appropriate complementary feeding practice.


Assuntos
Aleitamento Materno , Mães , Criança , Humanos , Feminino , Lactente , Pré-Escolar , Masculino , Estudos Transversais , Prevalência , Mães/educação , Índia/epidemiologia
8.
Food Funct ; 15(3): 1417-1430, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38224157

RESUMO

This study investigated the non-inferiority of feeding term healthy infants with enriched formula milk powder containing 1,3-dioleoyl-2-palmitoylglycerol (OPO) and milk fat globular membrane (MFGM), compared to breast milk, in terms of the formation of gut microbiota, neurodevelopment and growth. Infants were divided into three groups: breast milk group (BMG, N = 50), fortified formula group (FFG, N = 17), and regular formula group (RFG, N = 12), based on the feeding pattern. Growth and development information was collected from the infants at one month, four months, and six months after the intervention. Fecal samples were collected from infants and analyzed for gut microbiota using 16S ribosomal DNA identification. The study found that at the three time points, the predominant bacterial phyla in FFG and BMG were Proteobacteria, Firmicutes, and Bacteroidetes, which differed from RFG. The abundance of Bifidobacterium in the RFG was lower than the FFG (one month, p = 0.019) and BMG (four months, p = 0.007). The abundance of Methanoprebacteria and so on (genus level) are positively correlated with bone mineral density (BMD) of term infants, and have the potential to be biomarkers for predicting BMD. The abundance of beta-galactosidase, a protein that regulates lactose metabolism and sphingoid metabolism, was higher in FFG (six months, p = 0.0033) and BMG (one month, p = 0.0089; four months, p = 0.0005; six months, p = 0.0005) than in the RFG group, which may be related to the superior bone mineral density and neurodevelopment of infants in the FFG and BMG groups than in the RFG group. Our findings suggest that formula milk powder supplemented with OPO and MFGM is a viable alternative to breastfeeding, providing a practical alternative for infants who cannot be breastfed for various reasons.


Assuntos
Aleitamento Materno , Microbioma Gastrointestinal , Lactente , Feminino , Humanos , Pós , Fórmulas Infantis , Leite Humano , Fezes/microbiologia
9.
ACS Sens ; 9(1): 236-243, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38123468

RESUMO

Organic molecules are of great interest for gas sensing applications. However, achieving high-performance gas sensors with high sensitivity, fast response, low consumption, and workability in humid conditions is still challenging. Herein, we report the rational design and synthesis of an ion-in-conjugation polymer, PADC (poly-4,4'-azodianiline-croconamide), obtained by the condensation of croconic acid with 4-4'diaminoazobenzene for gas sensing under humid conditions. The as-fabricated PADC-based gas sensor exhibits ultrahigh sensitivity (802.7 ppm-1 at 1 ppm), subppb detection limit, and high selectivity under humid air with an 80% humidity effect at a temperature down to 350 K. PADC shows good planarity, excellent thermostability, and a narrow band gap of 1.2 eV because of azobenzene fragments spacing previously repulsed biphenyl rings. Compared to previous humidity immunity works, PADC-based sensors realized humidity immunity at a relatively lower temperature, resulting in lower energy consumption.


Assuntos
Dióxido de Nitrogênio , Poli A , Umidade , Polímeros , Temperatura
10.
Lancet Glob Health ; 11(12): e1863-e1873, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37973337

RESUMO

BACKGROUND: In low-income and middle-income countries (LMICs), intimate partner violence poses a substantial barrier to accomplishing target 5.2 of the Sustainable Development Goals: to eliminate all forms of violence against women and girls. Our study aimed to assess the prevalence and changes of intimate partner violence against women in LMICs. We also explored the association between women's empowerment and intimate partner violence. METHODS: In this secondary analysis of population-based surveys, we obtained data from the nationally representative Demographic and Health Surveys conducted in LMICs between 2000 and 2021. We selected countries with available data on the domestic violence module, and women aged 15 to 49 years who currently or formerly had a husband or partner, and who had provided information about intimate partner violence, were included in the analysis. We first estimated the weighted prevalence of intimate partner violence in LMICs with available data, and then we assessed the average annual rate of change using Poisson regression with robust error variance in a subset of countries with at least two surveys. We used multilevel analysis to investigate the association between intimate partner violence and women's empowerment measured at both the country and individual levels. Country-level empowerment was measured by gender inequality index, while individual-level empowerment considered social independence, decision making, and attitude to violence. FINDINGS: A total of 359 479 women aged 15 to 49 years were included from 53 LMICs. 336 811 women from 21 countries with two surveys provided data for assessing the trends of intimate partner violence. The weighted prevalence of any type of intimate partner violence was 37·2% (95% CI 36·6 to 37·8). A significant overall decline in the prevalence of any type of intimate partner violence was observed with an average annual rate of change of -0·2% (95% CI -0·4 to -0·03); however six countries showed significant increasing trends, with average annual rates of change ranging from 1·2% (95% CI 0·7 to 1·7) in Nigeria to 6·6% (5·3 to 7·8) in Sierra Leone. Notably, the prevalence of psychological intimate partner violence has risen (average annual rate of change, 2·3% [95% CI 2·1 to 2·6]), reflected in increased rates across eight countries. Higher levels of country-level women's empowerment were associated with a lower risk of intimate partner violence: women from countries with the highest tertile of gender inequality index had an increased odds of any type of intimate partner violence (odds ratio 1·58 [95% CI 1·12 to 2·23]). Similarly, better individual-level women's empowerment also showed significant associations with a lower risk of intimate partner violence. INTERPRETATION: The prevalence of intimate partner violence remains high, and some countries have shown an increasing trend. The strong relationship between both country-level and individual-level women's empowerment and the prevalence of intimate partner violence suggests that accelerating women's empowerment could be one strategy to further reduce intimate partner violence against women. FUNDING: National Natural Science Foundation; Vanke School of Public Health, Tsinghua University; and Sanming Project of Medicine in Shenzhen.


Assuntos
Países em Desenvolvimento , Violência por Parceiro Íntimo , Humanos , Feminino , Prevalência , Fatores de Risco , Violência
11.
Colloids Surf B Biointerfaces ; 231: 113568, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37826963

RESUMO

Circulating tumor cells (CTCs) are important biomarkers in cancer diagnosis. However, the specific labeling of CTCs with high capture efficiency in whole blood remains a problem. Herein, a dual-source-driven nanomotor coupled with dual-targeting ligands (CD@NM) was designed for efficient capture, specific imaging and quantitative detection of CTCs. In both water and biological fluid, CD@NMs moved autonomously under the propulsion of a magnetic field and H2O2 solution, which improved the capture efficiency of CTCs to 97.50 ± 2.38%. More importantly, specific labeling of CTCs was achieved by fluorescence quenching and recovery of fluorescent carbon dots modified on the CD@NMs. As a result, the CD@NMs exhibited efficient CTC capture, specific CTC imaging and recognition in whole blood. CD@NMs were also successfully deployed in the specific imaging of tumor tissues in vivo. On this basis, CD@NMs are expected to provide a new platform for tumor diagnosis both in vitro and in vivo.


Assuntos
Peróxido de Hidrogênio , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patologia , Fluorescência , Linhagem Celular Tumoral , Separação Celular/métodos
12.
Opt Lett ; 48(20): 5265-5268, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37831843

RESUMO

Antimony sulfide (Sb2S3) photodetectors (PDs) have great potential in commercial applications. The performances are affected by photocarrier distribution and recombination. Here, the gate-controlled Sb2S3 thin film PD is fabricated on the TiO2/SiO2/Si substrate by the vacuum method. The p-channel Sb2S3 transistor obtained a threshold voltage of 0.6 V and a switching ratio of 1064, achieving an effective regulation by gate voltages. A negative gate voltage can enhance conductivity and can suppress recombination. The responsivity and detectivity of the PD reach 1.6 A/W and 1.2 × 1011 Jones, respectively. The device realizes logic outputs by the signal inputs of illumination and gate voltage.

13.
Sci Rep ; 13(1): 13187, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580482

RESUMO

The stability of rock pillar is crucial for ensuring the construction safety of twin tunnels with small clearance, especially when transitioning from the traditional left-right tunnel layouts to the up-down configurations due to complex and variable site constraints. However, there are limited researches on the evaluation and comparative study of the stability of these two types of rock pillars in twin tunnels. This paper introduces the yield approach index (YAI) as a measure to assess the stability of rock pillar in twin tunnels with small clearance, and various influencing factors including side pressure coefficient (SPC), stress release rate (SRR), and the thickness of rock pillar (characterised by the ratio of rock pillar thickness to tunnel diameter, RPT/TD) are considered in the analysis. The study compares and analyzes the stability differences of the rock pillar in different situations. It is observed that the two sides of up-down tunnels pose a higher risk while the rock pillar in the left-right configuration being the most vulnerable. The stability of the rock pillar between the up-down tunnels is significantly higher than that of the left-right tunnels under similar conditions. Moreover, the up-down tunnels exhibit greater sensitivity to SPC, whereas the left-right tunnels are more sensitive to SRR. Additionally, the study reveals that increasing the RPT/TD can effectively improve the stability of the rock pillar within a specific range (1/4 to 2/3). The research method and obtained results of this paper can provide some important references for the stability evaluation and design of twin tunnels with small clearance.

14.
Small ; 19(50): e2303932, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37612814

RESUMO

The slow charge transfer and high energy barrier are the key restrictions of cost-effective electrocatalysts for hydrogen production. A hierarchical heterostructure of MoN@NiFe-layered double hydroxides (LDH) is developed, with NiFe-LDH nanosheets supported on MoN nanowire arrays. The as-prepared MoN@NiFe-LDH exhibits a remarkably high performance on hydrogen production in alkaline medium, which is close to the benchmark Pt/C. The theoretical computations indicate that MoN@NiFe-LDH has a metallic character inherited from MoN, which gives rise to the promoted charge transfer. Furthermore, the adsorption intensity of intermediates on MoN@NiFe-LDH is optimized and thereby the energy barrier is diminished. This work demonstrates the significance of constructing heterostructure for boosting the charge transfer and reducing the energy barrier, which can shed light on the development of highly efficient and low-cost electrocatalyst for hydrogen production.

15.
ACS Nano ; 17(15): 14883-14892, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37487002

RESUMO

Lightweight, flexible, and noncombustible thermo-acoustic insulating (TAI) materials have great potential in vehicles, cold-chain transportation, and aerospace engineering, where weight and space savings are critical. However, the TAI capabilities of many commodities are hindered by the lack of diverse and reasonable resonant cavities with broadband and highly efficient acoustic responsiveness. This study demonstrates a layer-by-layer freeze-casting method for superelastic cellular aerogel construction from varied nanofibers and ice particulates with widely distributed resonant cavities from 0.5 to 300 µm. The method enabled the cumulative freezing of the nanofiber solution from one side to the other side, resulting in vertical pore channels with random holes across the entire freezing distance. The formed cellular networks of stable hinged ternary nanofiber membranes, functionalized as ultrathin nanofiber drums, exhibit strong resonances and efficiently dissipate sound waves in a broad frequency range. A high noise reduction coefficient of 0.65 at a frequency range of 63-6300 Hz and a low thermal conductivity of 0.026 W m-1 K-1 at room temperature was obtained. This work presents the bottom-up fabrication of high-performance TAI aerogels that are beneficial for practical energy-saving devices and buildings and broadband acoustic absorption applications.

16.
Chem Commun (Camb) ; 59(65): 9876-9879, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37492025

RESUMO

Two perylenediimide (PDI) regioisomers with the central core substituted at the ortho (Y-αPDI) and bay (Y-ßPDI) areas of the PDIs were successfully prepared. The regioisomeric effects on the physicochemical and charge-transport properties were thoroughly investigated. The results unravel that Y-ßPDI shows ambipolar transport with higher mobilities compared to its α-counterpart, which is due to its favourable molecular geometry, stronger intermolecular interaction and improved electron-withdrawing ability.

17.
Nat Commun ; 14(1): 4324, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468474

RESUMO

Solitary waves are unique in nonlinear systems, but their formation and propagation in the nonlinear fluid-structure interactions have yet to be further explored. As a typical nonlinear system, the buckling of solid thin films is fundamentally related to the film-substrate interface that is further vulnerable to environments, especially when fluids exist. In this work, we report an anomalous, solitary-wave-like blister (SWLB) mode of MoS2 thin films in a humid environment. Unlike the most common telephone-cord and web buckling deformation, the SWLB propagates forward like solitary waves that usually appear in fluids and exhibits three-dimensional expansions of the profiles during propagation. In situ mechanical, optical, and topology measurements verify the existence of an interfacial water nanolayer, which facilitates a delamination of films at the front side of the SWLB and a readhesion at the tail side owing to the water nanolayer-induced fluid-structure interaction. Furthermore, the expansion morphologies and process of the SWLB are predicted by our theoretical model based on the energy change of buckle propagation. Our work not only demonstrates the emerging SWLB mode in a solid material but also sheds light on the significance of interfacial water nanolayers to structural deformation and functional applications of thin films.

18.
Angew Chem Int Ed Engl ; 62(26): e202303551, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37099418

RESUMO

High efficiency organic solar cells (OSCs) based on A-DA'D-A type small molecule acceptors (SMAs) were mostly fabricated by toxic halogenated solvent processing, and power conversion efficiency (PCE) of the non-halogenated solvent processed OSCs is mainly restricted by the excessive aggregation of the SMAs. To address this issue, we developed two vinyl π-spacer linking-site isomerized giant molecule acceptors (GMAs) with the π-spacer linking on the inner carbon (EV-i) or out carbon (EV-o) of benzene end group of the SMA with longer alkyl side chains (ECOD) for the capability of non-halogenated solvent-processing. Interestingly, EV-i possesses a twisted molecular structure but enhanced conjugation, while EV-o shows a better planar molecular structure but weakened conjugation. The OSC with EV-i as acceptor processed by the non-halogenated solvent o-xylene (o-XY) demonstrated a higher PCE of 18.27 % than that of the devices based on the acceptor of ECOD (16.40 %) or EV-o (2.50 %). 18.27 % is one of the highest PCEs among the OSCs fabricated from non-halogenated solvents so far, benefitted from the suitable twisted structure, stronger absorbance and high charge carrier mobility of EV-i. The results indicate that the GMAs with suitable linking site would be the excellent candidates for fabricating high performance OSCs processed by non-halogenated solvents.


Assuntos
Benzeno , Carbono , Eritromicina , Cloreto de Polivinila , Solventes
19.
Nat Commun ; 14(1): 2133, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37069153

RESUMO

Two-dimensional covalent organic frameworks (2D COFs) are promising for gas sensing owing to the large surface area, abundant active sites, and their semiconducting nature. However, 2D COFs are usually produced in the form of insoluble micro-crystallites. Their poor contacts between grain boundaries severely suppress the conductivity, which are too low for chemresistive gas sensing. Here, we demonstrate that halide perovskites can be employed as electric glues to bond 2D COF crystallites to improve their conductivity by two orders of magnitude, activating them to detect NO2 with high selectivity and sensitivity. Resonant microcantilever, grand canonical Monte Carlo, density functional theory and sum-frequency generation analyses prove that 2D COFs can enrich and transfer electrons to NO2 molecules, leading to increased device conductivity. This work provides a facile approach for improving the conductivity of polycrystalline 2D COF films and may expand their applications in semiconductor devices, such as sensors, resistors, memristors and field-emission transistors.

20.
J Clin Ultrasound ; 51(4): 628-635, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36300864

RESUMO

PURPOSE: To explore the applicability of the Tei index combined with lung ultrasound score (LUS) in the evaluation of the lung condition and the right ventricular function of patients with neonatal pulmonary hypertension (PH). METHODS: Thirty healthy neonates and 75 neonates with PH were included. Two-dimensional, M-mode, and double Doppler ultrasound were used to detect RVFAC, TAPSE, TAPSV, and double Doppler Tei index (DD-Tei index). Intra-group correlation coefficient (ICC), Bland-Altman, the Spearman rank method, and the ROC (receiver operating characteristic) were used for other objectives within the study. LUS was used to score the lung condition of 75 neonates with PH with or without respiratory distress and 30 normal neonates in the control group, and the differences were compared. Spearman rank correlation was used to analyze the lung score, DD-Tei index, pulmonary artery pressure, assisted breathing therapy, and the correlation of invasive mechanical ventilation. RESULTS: There were statistically significant differences in the decrease of the values of RVFAC, TAPSE, TAPSV, and the increase of the DD-Tei index among the groups. RVFAC, TAPSE, TAPSV, and DD-Tei index showed good performance for PH, and the DD-Tei index had the best diagnostic performance. The increase in pulmonary artery pressure, lung score, and DD-Tei index in the PH were statistically significant compared with the control group. The DD-Tei index and lung scores were positively correlated with pulmonary artery pressure, assisted breathing therapy, and invasive mechanical ventilation. CONCLUSION: Dual Doppler ultrasonography combined with pulmonary ultrasound performed well in the assessment of the right ventricular function and lung condition of neonatal with PH.


Assuntos
Hipertensão Pulmonar , Recém-Nascido , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Função Ventricular Direita , Pulmão/diagnóstico por imagem , Ultrassonografia Doppler , Curva ROC
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