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1.
Nano Lett ; 24(20): 5929-5936, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38655909

RESUMO

Multiferroic materials provide robust and efficient routes for the control of magnetism by electric fields, which have been diligently sought after for a long time. Construction of two-dimensional (2D) vdW multiferroics is a more exciting endeavor. To date, the nonvolatile manipulation of magnetism through ferroelectric polarization still remains challenging in a 2D vdW heterostructure multiferroic. Here, we report a van der Waals (vdW) heterostructure multiferroic comprising the atomically thin layered antiferromagnet (AFM) CrI3 and ferroelectric (FE) α-In2Se3. We demonstrate anomalously nonreciprocal and nonvolatile electric-field control of magnetization by ferroelectric polarization. The nonreciprocal electric control originates from an intriguing antisymmetric enhancement of interlayer ferromagnetic coupling in the opposite ferroelectric polarization configurations of α-In2Se3. Our work provides numerous possibilities for creating diverse heterostructure multiferroics at the limit of a few atomic layers for multistage magnetic memories and brain-inspired in-memory computing.

2.
J Am Chem Soc ; 146(17): 11764-11772, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38625675

RESUMO

Direct imaging of single molecules at nanostructured interfaces is a grand challenge with potential to enable new, precise material architectures and technologies. Of particular interest are the structural morphology and spectroscopic signatures of the adsorbed molecule, where modern probes are only now being developed with the necessary spatial and energetic resolution to provide detailed information at the molecule-surface interface. Here, we directly characterize the adsorption of individual m-terphenyl isocyanide ligands on a reconstructed Au(111) surface through scanning tunneling microscopy and inelastic electron tunneling spectroscopy. The site-dependent steric pressure of the various surface features alters the vibrational fingerprints of the m-terphenyl isocyanides, which are characterized with single-molecule precision through joint experimental and theoretical approaches. This study provides molecular-level insights into the steric-pressure-enabled surface binding selectivity as well as its effect on the chemical properties of individual surface-binding ligands.

3.
Small ; 20(14): e2307405, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37988711

RESUMO

The nitridation of noble metals-based catalysts to further enhance their hydrogen evolution reaction (HER) kinetics in neutral and alkaline conditions would be an effective strategy for developing high-performance wide pH HER catalysts. Herein, a facile molten urea method is employed to construct the nitrided Rh nanoclusters (RhxN) supported on N-doped carbon (RhxN-NC). The uniformly distributed RhxN clusters exhibited optimized water bonding and splitting effects, therefore resulting in excellent pH-universal HER performance. The optimized RhxN-NC catalyst only requires 8, 12, and 109 mV overpotentials to reach the current density of 10 mA cm-2 in 0.5 M H2SO4, 1.0 M KOH, and 1.0 M PBS electrolytes, respectively. The spectroscopic characterizations and theoretical calculation further confirm the vital role of Rh-N moieties in RhxN clusters in improving the transfer of electrons and facilitating the generation of H2. This work not only provides a suitable nitridation method for noble metal species in mild conditions but also makes a breakthrough in synthesizing noble metal nitrides-based electrocatalysts to achieve an exceptional wide-pH HER performance and other catalysis.

4.
Cell Biol Toxicol ; 40(1): 22, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630149

RESUMO

Uremic encephalopathy (UE) poses a significant challenge in neurology, leading to the need to investigate the involvement of non-coding RNA (ncRNA) in its development. This study employed ncRNA-seq and RNA-seq approaches to identify fundamental ncRNAs, specifically circRNA and miRNA, in the pathogenesis of UE using a mouse model. In vitro and in vivo experiments were conducted to explore the circRNA-PTPN4/miR-301a-3p/FOXO3 axis and its effects on blood-brain barrier (BBB) function and cognitive abilities. The research revealed that circRNA-PTPN4 binds to and inhibits miR-301a-3p, leading to an increase in FOXO3 expression. This upregulation results in alterations in the transcriptional regulation of ZO-1, affecting the permeability of human brain microvascular endothelial cells (HBMECs). The axis also influences the growth, proliferation, and migration of HBMECs. Mice with UE exhibited cognitive deficits, which were reversed by overexpression of circRNA-PTPN4, whereas silencing FOXO3 exacerbated these deficits. Furthermore, the uremic mice showed neuronal loss, inflammation, and dysfunction in the BBB, with the expression of circRNA-PTPN4 demonstrating therapeutic effects. In conclusion, circRNA-PTPN4 plays a role in promoting FOXO3 expression by sequestering miR-301a-3p, ultimately leading to the upregulation of ZO-1 expression and restoration of BBB function in mice with UE. This process contributes to the restoration of cognitive abilities.


Assuntos
Barreira Hematoencefálica , Cognição , Proteína Forkhead Box O3 , MicroRNAs , RNA Circular , Humanos , Encefalopatias , Células Endoteliais , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , MicroRNAs/genética , Proteína Tirosina Fosfatase não Receptora Tipo 4 , RNA Circular/genética
5.
Phys Chem Chem Phys ; 26(27): 18727-18740, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38934056

RESUMO

The utilization of InP-based biocompatible quantum dots (QDs) necessitates a comprehensive understanding of the structure-dependent characteristics influencing their optical behavior. The optimization of core/shell QDs for practical applications is of particular interest due to their reduced toxicity, enhanced photostability, and improved luminescence efficiency. This optimization involves analyzing thermally activated processes involving exciton and defect-related energy levels. This study investigates water-soluble colloidal InP/ZnS QDs with varying shell thicknesses and stabilizing coatings using temperature-dependent optical absorption (OA) and photoluminescence (PL). Our results indicate that all samples experience temperature-induced shifts in exciton absorption and luminescence peaks due to interactions with acoustic phonons. Despite the wide size distribution of nanocrystals, the halfwidth of the bands remains constant. We observe a temperature-dependent Stokes shift in InP/ZnS QDs, revealing the fine structure of exciton states across different configurations. Furthermore, our findings demonstrate common mechanisms underlying PL thermal quenching in these QDs, regardless of the shell thickness or coating type. Specifically, defect-related emissions arise from localized energy levels at the core/shell interface. At the same time, exciton PL quenching primarily occurs through thermally activated electron migration from the InP core to the ZnS shell. Overall, our study highlights the potential for tailoring the temperature response of InP/ZnS QDs by adjusting shell thickness, offering opportunities to optimize their performance for specific applications.

6.
BMC Pediatr ; 24(1): 506, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112952

RESUMO

BACKGROUND: Early childhood caries (ECC) is a challenge for pediatric dentists all over the world, and dietary factor is an important factor affecting the occurrence of ECC. Currently, there is limited research on the impact of dietary nutrient intake from Chinese diets on ECC. The purpose of this study is to explore the correlation of dietary nutrients intake with ECC and caries activity (CA) among children aged 3-5 years, and to provide dietary guidance to slow down the occurrence and development of ECC. METHODS: A cross-sectional study was conducted in 2022. A total of 155 children were divided into three groups: caries-free group, ECC group and Severe early childhood caries (SECC) group according to the caries statues. And according to the caries activity test (CAT) value, they were also divided into three group: low CA group (L-CA), middle CA group (M-CA) and high CA group (H-CA). The 24-hour dietary intake information was collected by mobile phone application (APP). The intake of children's daily dietary nutrients were calculated referring to "China Food Composition Tables". RESULTS: In this study, 17, 39,and 99 children were diagnosed with caries-free, ECC, and SECC. There were 33, 36, and 86 children diagnosed with L-CA, M-CA, and H-CA. The risk of ECC was increased with the intake of cholesterol(OR = 1.005) and magnesium (OR = 1.026) and decreased with the intake of iron (OR = 0.770). The risk of SECC was increased with the intake of cholesterol (OR = 1.003). The risk of high CA was increased with the intake of cholesterol (OR = 1.002). The combined application of dietary total calories, carbohydrate, cholesterol, sodium, magnesium and selenium in the diagnosis of ECC had an area under ROC curve of 0.741. CONCLUSIONS: The increased dietary cholesterol intake may be a common risk factor for ECC and high CA in children aged 3-5. The combined application of dietary intake of total calories, carbohydrate, cholesterol, sodium, magnesium and selenium has a higher predictive value for the occurrence of ECC.


Assuntos
Cárie Dentária , Humanos , Estudos Transversais , Pré-Escolar , Cárie Dentária/epidemiologia , Cárie Dentária/etiologia , Cárie Dentária/prevenção & controle , Masculino , Feminino , China/epidemiologia , Dieta , Nutrientes/administração & dosagem , Ingestão de Energia
7.
J Ultrasound Med ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39230251

RESUMO

OBJECTIVES: To explore the clinical value of the nomogram based on ultrasound spectral combined with clinical pathological parameter in predicting axillary lymph node metastasis in breast cancer. METHODS: We prospectively gathered clinicopathologic and ultrasonic data from 240 patients confirmed breast cancer. The risk factors of axillary lymph node metastasis were analyzed by univariate and multivariate logistic regression, and the prediction model was established. The model calibration, predictive ability, and diagnostic efficiency in the training set and the testing set were analyzed by receiver operating characteristic curve and calibration curve analysis, respectively. RESULTS: Univariate analysis showed that lymph node metastasis was related with tumor size, Ki-67, axillary ultrasound, ultrasound spectral quantitative parameter, internal echo, and calcification (P < .05). Multivariate logistic regression analysis showed that the Ki-67, axillary ultrasound, quantitative parameter (the mean of the mid-band fit in tumor and posterior tumor) were independent risk factors of axillary lymph node metastasis (P < .05). The models developed using Ki-67, axillary ultrasound, and quantitative parameters for predicting axillary lymph node metastasis demonstrated an area under the receiver operating characteristic curve of 0.83. Additionally, the prediction model exhibited outstanding predictability for axillary lymph node metastasis, as evidenced by a Harrell C-index of 0.83 (95% confidence interval 0.73-0.93). CONCLUSION: Axillary ultrasound combined with Ki-67 and ultrasound spectral parameters has the potential to predict axillary lymph node metastasis in breast cancer, which is superior to axillary ultrasound alone.

8.
Ecotoxicol Environ Saf ; 284: 116867, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39154501

RESUMO

The loss of nitrogen in soil damages the environment. Clarifying the mechanism of ammonium nitrogen (NH4+-N) transport in soil and increasing the fixation of NH4+-N after N application are effective methods for improving N use efficiency. However, the main factors are not easily identified because of the complicated transport and retardation factors in different soils. This study employed machine learning (ML) to identify the main influencing factors that contribute to the retardation factor (Rf) of NH4+-N in soil. First, NH4+-N transport in the soil was investigated using column experiments and a transport model. The Rf (1.29 - 17.42) was calculated and used as a proxy for the efficacy of NH4+-N transport. Second, the physicochemical parameters of the soil were determined and screened using lasso and ridge regressions as inputs for the ML model. Third, six machine learning models were evaluated: Adaptive Boosting, Extreme Gradient Boosting (XGB), Random Forest, Gradient Boosting Regression, Multilayer Perceptron, and Support Vector Regression. The optimal ML model of the XGB model with a low mean absolute error (0.81), mean squared error (0.50), and high test r2 (0.97) was obtained by random sampling and five-fold cross-validation. Finally, SHapely Additive exPlanations, entropy-based feature importance, and permutation characteristic importance were used for global interpretation. The cation exchange capacity (CEC), total organic carbon (TOC), and Kaolin had the greatest effects on NH4+-N transport in the soil. The accumulated local effect offered a fundamental insight: When CEC > 6 cmol+ kg-1, and TOC > 40 g kg-1, the maximum resistance to NH4+-N transport within the soil was observed. This study provides a novel approach for predicting the impact of the soil environment on NH4+-N transport and guiding the establishment of an early-warning system of nutrient loss.

9.
BMC Oral Health ; 24(1): 1035, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227939

RESUMO

BACKGROUND: This study aims to investigate the association between malnutrition and early childhood caries (ECC) and caries activity among children aged 3-5 years, in order to provide a theoretical basis for preventing and blocking ECC and improving malnutrition. METHODS: Children aged 3-5 years from six kindergartens in Zhao Xian, China were enrolled in this study. The decayed, missing, filled teeth (dmft) of all children were examined and recorded. The Cariostat method was used to detect dental caries activity, collect anthropometric data and measure haemoglobin concentration. Parents were asked to complete a questionnaire on the general characteristics and oral health behaviour of the participants. The "Growth Standards for Chinese Children Under 7 Years Old" was used to assess the nutritional status of all participating children. Wilcoxon rank sum test and multivariate logistic regression analysis were used to analyse and evaluate the relationship between ECC, caries activity and malnutrition. RESULTS: A total of 635 children who met the criteria were included in this study. After adjusting for confounding factors, logistic regression showed that the risk of ECC was significantly increased in underweight children compared with normal children (OR = 5.43, P < 0. 05); compared with normal children, the risk of ECC decreased in overweight and obese children (OR = 0.31, P < 0.001); underweight children had higher caries severity than normal weight children, and the difference was statistically significant (OR = 2.69, P < 0. 05); stunted children had higher caries severity than normal weight children and the difference was statistically significant (OR = 2.28, P < 0.05); underweight was positively associated with caries activity and the association was statistically significant (OR = 2.33, P < 0. 05); stunting was positively associated with caries activity and the association was statistically significant (OR = 2.1, P < 0.05); overweight and obesity were negatively associated with caries activity and the association was statistically significant (OR = 0.61, P < 0.05). CONCLUSIONS: The risk of ECC among children aged 3-5 years was positively associated with undernutrition and negatively associated with overnutrition. The severity of ECC among children aged 3-5 years was positively associated with undernutrition. The caries activity among children aged 3-5 years was positively associated with undernutrition and negatively associated with overnutrition.


Assuntos
Índice CPO , Cárie Dentária , Humanos , Cárie Dentária/epidemiologia , Pré-Escolar , Masculino , Feminino , China/epidemiologia , Desnutrição/complicações , Desnutrição/epidemiologia , Magreza/complicações , Sobrepeso/complicações , Estado Nutricional , Hemoglobinas/análise , Fatores de Risco , Índice de Massa Corporal , Obesidade/complicações , Obesidade/epidemiologia , Antropometria
10.
Development ; 147(6)2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32098764

RESUMO

Neocortex development during embryonic stages requires the precise control of mRNA metabolism. Human antigen R (HuR) is a well-studied mRNA-binding protein that regulates mRNA metabolism, and it is highly expressed in the neocortex during developmental stages. Deletion of HuR does not impair neural progenitor cell proliferation or differentiation, but it disturbs the laminar structure of the neocortex. We report that HuR is expressed in postmitotic projection neurons during mouse brain development. Specifically, depletion of HuR in these neurons led to a mislocalization of CDP+ neurons in deeper layers of the cortex. Time-lapse microscopy showed that HuR was required for the promotion of cell motility in migrating neurons. PCR array identified profilin 1 (Pfn1) mRNA as a major binding partner of HuR in neurons. HuR positively mediated the stability of Pfn1 mRNA and influenced actin polymerization. Overexpression of Pfn1 successfully rescued the migration defects of HuR-deleted neurons. Our data reveal a post-transcriptional mechanism that maintains actin dynamics during neuronal migration.


Assuntos
Movimento Celular , Proteína Semelhante a ELAV 1/fisiologia , Neurônios/fisiologia , RNA Mensageiro/metabolismo , Animais , Padronização Corporal/genética , Movimento Celular/genética , Células Cultivadas , Embrião de Mamíferos , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células-Tronco Neurais/fisiologia , Neurogênese/genética , Gravidez , Profilinas/fisiologia , Processamento Pós-Transcricional do RNA/genética
11.
Small ; 19(10): e2206808, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36539263

RESUMO

Tuning the microenvironment and electronic structure of support materials is essential strategy to induce electron transfer between supports and active centers, which is of great importance in optimizing catalytic kinetics. In this study, the molybdenum oxycarbide supported Rh-clusters are synthesized with modulated interstitial C-O microenvironments (Rh/MoOC) for promoting efficient hydrogen evolution in water splitting. Both electronic structure characterizations and theoretical calculations uncover the apparent charge transfer from Rh to MoOC, which optimizes the d-band center, H2 O adsorption energy, and hydrogen binding energy, thus enhancing its intrinsic hydrogen-evolving activities. In addition, the co-occurrence of interstitial C and O atoms in MoOC supports plays a vital role in the dissociation reaction of water during the hydrogen-evolving process. Impressively, the Rh/MoOC exhibits excellent hydrogen-evolving activities in terms of exceptional turnover frequency values (11.4 and 39.41 H2 s-1 in alkaline and acidic media) and mass activities (21.3 and 73.87 A mg-1 in alkaline and acidic media) at an overpotential of 100 mV, which is more than 40 times higher than that of the benchmark commercial Rh/C catalysts. This work sheds new light on designing water dissociation materials that surpasses most of the reported catalysts.

12.
Ecotoxicol Environ Saf ; 257: 114908, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37080128

RESUMO

N-doped biochar is widely used for activating persulfate to degrade organic pollutants. Which type of N atom is the key factor for activation is still unclear and needs to be further explored and analyzed. In this study, four kinds of biochar were prepared using urea and rice husk as precursors, and tested for the catalytic degradation of dimethomorph. Increasing the nitrogen doping level caused the catalytic removal efficiency of dimethomorph in the presence of peroxymonosulfate increased from 16.6% to 86.8%. A correlation analysis showed that the ability of N-doped biochar to activate PMS is mainly related to the content of pyrrole N, graphite N and carbonyl and the degree of defects. In experiments on electron paramagnetic resonance and free radical suppression, the reactive species of SO4•-, 1O2,·OH and O2.- were detected, among which 1O2 was found to be the main agent in the nonradical pathway. The degradation pathways for dimethomorph were analyzed based on a total of 8 degradation products identified by high-performance liquid chromatography-time of flight mass spectrometry (HPLC-Q-TOFMS). The results of this study provide a fundamental basis for using agricultural waste to produce inexpensive and efficient nonmetal catalysts that are highly effective in reducing dimethomorph levels in agricultural lands.


Assuntos
Oryza , Nitrogênio/química , Carvão Vegetal , Peróxidos/química
13.
Sensors (Basel) ; 23(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37447829

RESUMO

With the maturity of Unmanned Aerial Vehicle (UAV) technology and the development of Industrial Internet of Things, drones have become an indispensable part of intelligent transportation systems. Due to the absence of an effective identification scheme, most commercial drones suffer from impersonation attacks during their flight procedure. Some pioneering works have already attempted to validate the pilot's legal status at the beginning and during the flight time. However, the off-the-shelf pilot identification scheme can not adapt to the dynamic pilot membership management due to a lack of extensibility. To address this challenge, we propose an incremental learning-based drone pilot identification scheme to protect drones from impersonation attacks. By utilizing the pilot temporal operational behavioral traits, the proposed identification scheme could validate pilot legal status and dynamically adapt newly registered pilots into a well-constructed identification scheme for dynamic pilot membership management. After systemic experiments, the proposed scheme was capable of achieving the best average identification accuracy with 95.71% on P450 and 94.23% on S500. With the number of registered pilots being increased, the proposed scheme still maintains high identification performance for the newly added and the previously registered pilots. Owing to the minimal system overhead, this identification scheme demonstrates high potential to protect drones from impersonation attacks.


Assuntos
Aprendizagem , Dispositivos Aéreos não Tripulados , Indústrias , Inteligência , Internet
14.
Sensors (Basel) ; 23(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37837135

RESUMO

In contrast to traditional phase-shifting (PS) algorithms, which rely on capturing multiple fringe patterns with different phase shifts, digital PS algorithms provide a competitive alternative to relative phase retrieval, which achieves improved efficiency since only one pattern is required for multiple PS pattern generation. Recent deep learning-based algorithms further enhance the retrieved phase quality of complex surfaces with discontinuity, achieving state-of-the-art performance. However, since much attention has been paid to understanding image intensity mapping, such as supervision via fringe intensity loss, global temporal dependency between patterns is often ignored, which leaves room for further improvement. In this paper, we propose a deep learning model-based digital PS algorithm, termed PSNet. A loss combining both local and global temporal information among the generated fringe patterns has been constructed, which forces the model to learn inter-frame dependency between adjacent patterns, and hence leads to the improved accuracy of PS pattern generation and the associated phase retrieval. Both simulation and real-world experimental results have demonstrated the efficacy and improvement of the proposed algorithm against the state of the art.

15.
Small ; 18(15): e2104411, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35233951

RESUMO

Exploring highly efficient, stable, and cost-effective bifunctional electrocatalysts is crucial for the wide commercialization of rechargeable Zn-air batteries. Herein, a vanadium-oxide-based hybrid air electrode comprising a heterostructure of V2 O3 and MnS (V2 O3 /MnS) is reported. The V2 O3 /MnS catalyst shows a decent catalytic activity that is comparable to Pt/C toward the oxygen reduction reaction and acceptable toward oxygen evolution. The extraordinary stability as well as the low cost set the V2 O3 /MnS among the best bifunctional oxygen electrocatalysts. In a demonstration of an assembled liquid-state Zn-air battery using V2 O3 /MnS as cathode, high power density (118 mW cm-2 ), specific capacity (808 mAh gZn -1 ), and energy density (970 Wh kgZn -1 ), as well as the outstanding rechargeability and durability for 4000 cycles (>1333 h, i.e., >55 days) are enabled. The V2 O3 /MnS is also integrated into an all-solid-state Zn-air battery to demonstrate its great potential as a flexible power source for next-generation electronics. Density functional theory calculations further elucidate the origin of the intrinsic activity and stability of the V2 O3 /MnS heterostructure.

16.
Small ; 18(51): e2205470, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36328710

RESUMO

Lithium-sulfur (Li-S) batteries have attracted great interest due to their low cost, high theoretical energy density, and environmental friendliness. However, the sluggish conversion of lithium polysulfides (LiPS) to S and Li2 S during the charge/discharge process leads to unsatisfactory rate performance of lower to 0.1 C (1 C = 1675 mA g-1 ) especially for Li-S pouch batteries, thus hindering their practical applications in high power batteries. Here, well-defined and monodispersed Ni single-atom catalysts (SACs) embedded in highly porous nitrogen-doped graphitic carbons (NiSA-N-PGC) are designed and synthesized to form Ni-N4 catalytic sites at the atomic level. When serving as a bifunctional electrocatalyst, the Ni-N4 catalytic sites cannot only promote the interfacial conversion redox of LiPS by accelerating the transformation kinetics, but also suppress the undesirable shuttle effect by immobilizing LiPS. These findings are verified by both experimental results and DFT theoretical calculations. Furthermore, Li ions show low diffusion barrier on the surface of Ni-N4 sites, resulting in enhanced areal capacity of batteries. As a result, the Li-S battery delivers stable cycling life of more than 600 cycles with 0.069% capacity decay per cycle at a rate of 0.5 C. More importantly, the Li-S pouch cells with NiSA-N-PGC show an initial capacity of 1299 mAh g-1 at a rate of 0.2 C even with high sulfur loading of 6 mg cm-2 . This work opens up an avenue for developing single-atom catalysts to accelerate the kinetic conversion of LiPS for highly stable Li-S batteries.

17.
Phys Chem Chem Phys ; 25(1): 203-208, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36504024

RESUMO

Although great efforts have been dedicated to exploring hydrogenated two-dimensional (2D) materials, there are few reports about the role of hydrogenation-induced equivalent strain effects in tuning the physical properties. Here, based on density functional theory, we systematically reveal the non-negligible role of the hydrogenation-induced strain and its effects on the electronic and optical properties in single-layer (SL) h10-Si. We demonstrate that hydrogenation can trigger an electronic transition from an indirect- to a direct-band-gap semiconductor mainly due to the energy level rearrangement of the partial p orbitals caused by the equivalent strain. The electronic transition in SL h10-Si occurs at a critical hydrogenation concentration of about 87.5%. Furthermore, it is found that hydrogenation can continuously shift the light absorption peak of SL h10-Si in the photon-energy range of 1.64-2.44 eV by changing the pz-pz dipole transition. Our findings provide an example of tuning the electronic properties of 2D materials via hydrogenation-induced strain, which is important for understanding the physical mechanism of the hydrogenation-tuned physical properties of such materials.

18.
Phys Chem Chem Phys ; 24(8): 4891-4898, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35137755

RESUMO

The unique structures of polynuclear MoxSy clusters make it possible to maximize the number of their active sites and for them to be good candidates for HER catalysts. An appropriate support is highly necessary not only to avoid the desorption of MoxSy clusters in a working environment, but also to improve their HER activity. Our work here shows that the CeO2 support could provide strong support for interaction with various MoxSy clusters and the formed MoxSy/CeO2 hetero-structures also have modest ΔGH* for the HER. The electronic features of MoxSy clusters are regulated by the CeO2 support, which leads to charge redistribution on edge atoms and plays a key role in H adsorption. Our studies provide instructive predictions on efficient candidates of molybdenum-sulfur based catalysts for the HER.

19.
Appl Opt ; 61(9): F1-F8, 2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35333220

RESUMO

In fringe projection profilometry, phase shifting (PS) is the most used technique for phase retrieval. However, it suffers from periodicity of sine wave in PS; the result is wrapped into [-π,π]; and additional phase unwrapping (PU) is necessary to retrieve the absolute phase. In this paper, a more general technique termed frequency shifting is proposed, based on which the behavior of periodicity is eliminated and absolute phase can be retrieved pixelwisely without any phase unwrapping. The effectiveness of the proposed technique was verified by extensive experimental results, and they demonstrate comparable performance with those of the traditional technique combining PS and PU even in only one step and less projection.

20.
Int J Clin Pract ; 2022: 1174521, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36628151

RESUMO

Objective: To evaluate the association between neutrophil levels and all-cause mortality in geriatric hip fractures. Methods: Elderly patients with hip fractures were screened between January 2015 and September 2019. Demographic and clinical characteristics of the patients were collected. Linear and nonlinear multivariate Cox regression models were used to identify the association between neutrophil levels and mortality. Analyses were performed using Empower Stats and R software. Results: A total of 2,589 patients were included in this study. The mean follow-up period was 38.95 months. During the study period, 875 (33.80%) patients died due to various causes. Linear multivariate Cox regression models showed that neutrophil levels were associated with mortality after adjusting for confounding factors, when neutrophil concentration increased by 1∗109/L, the mortality risk increased by 3% (HR = 1.03, 95% CI: 1.00-1.06, and P=0210). Neutrophil concentration was used as a categorical variable; we only found statistically significant differences when neutrophil levels were high (HR = 1.27, 95% CI:1.05-1.52, and P=0.0122). In addition, the results are stable in P for trend and propensity score matching sensitivity analysis. Conclusions: Neutrophil levels are associated with mortality in geriatric hip fractures and could be considered a predictor of death risk in the long-term. This study is registered with the Chinese Clinical Trial Registry (ChiCTR) as number ChiCTR2200057323.


Assuntos
Fraturas do Quadril , Neutrófilos , Humanos , Idoso , Estudos Prospectivos , Fatores de Risco
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