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1.
J Transl Med ; 22(1): 280, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491511

RESUMEN

BACKGROUND: Ovarian cancer (OC) is distinguished by its aggressive nature and the limited efficacy of current treatment strategies. Recent studies have emphasized the significant role of cancer-associated fibroblasts (CAFs) in OC development and progression. METHODS: Employing sophisticated machine learning techniques on bulk transcriptomic datasets, we identified fibroblast growth factor 7 (FGF7), derived from CAFs, as a potential oncogenic factor. We investigated the relationship between FGF7 expression and various clinical parameters. A series of in vitro experiments were undertaken to evaluate the effect of CAFs-derived FGF7 on OC cell activities, such as proliferation, migration, and invasion. Single-cell transcriptomic analysis was also conducted to elucidate the interaction between FGF7 and its receptor. Detailed mechanistic investigations sought to clarify the pathways through which FGF7 fosters OC progression. RESULTS: Our findings indicate that higher FGF7 levels correlate with advanced tumor stages, increased vascular invasion, and poorer prognosis. CAFs-derived FGF7 significantly enhanced OC cell proliferation, migration, and invasion. Single-cell analysis and in vitro studies revealed that CAFs-derived FGF7 inhibits the ubiquitination and degradation of hypoxia-inducible factor 1 alpha (HIF-1α) via FGFR2 interaction. Activation of the FGF7/HIF-1α pathway resulted in the upregulation of mesenchymal markers and downregulation of epithelial markers. Importantly, in vivo treatment with neutralizing antibodies targeting CAFs-derived FGF7 substantially reduced tumor growth. CONCLUSION: Neutralizing FGF7 in the medium or inhibiting HIF-1α signaling reversed the effects of FGF7-mediated EMT, emphasizing the dependence of FGF7-mediated EMT on HIF-1α activation. These findings suggest that targeting the FGF7/HIF-1α/EMT axis may offer new therapeutic opportunities to intervene in OC progression.


Asunto(s)
Fibroblastos Asociados al Cáncer , Neoplasias Ováricas , Humanos , Femenino , Fibroblastos Asociados al Cáncer/metabolismo , Factor 7 de Crecimiento de Fibroblastos/metabolismo , Factor 7 de Crecimiento de Fibroblastos/farmacología , Línea Celular Tumoral , Transducción de Señal , Neoplasias Ováricas/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Transición Epitelial-Mesenquimal/genética , Movimiento Celular/genética
2.
Adv Mater ; : e2308504, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38546279

RESUMEN

Anexelekto (AXL) is an attractive molecular target for ovarian cancer therapy because of its important role in ovarian cancer initiation and progression. To date, several AXL inhibitors have entered clinical trials for the treatment of ovarian cancer. However, the disadvantages of low AXL affinity and severe off-target toxicity of these inhibitors limit their further clinical applications. Herein, by rational design of a nonapeptide derivative Nap-Phe-Phe-Glu-Ile-Arg-Leu-Arg-Phe-Lys (Nap-IR), a strategy of in situ nanofiber formation is proposed to suppress ovarian cancer growth. After administration, Nap-IR specifically targets overexpressed AXL on ovarian cancer cell membranes and undergoes a receptor-instructed nanoparticle-to-nanofiber transition. In vivo and in vitro experiments demonstrate that in situ formed Nap-IR nanofibers efficiently induce apoptosis of ovarian cancer cells by blocking AXL activation and disrupting subsequent downstream signaling events. Remarkably, Nap-IR can synergistically enhance the anticancer effect of cisplatin against HO8910 ovarian tumors. It is anticipated that the Nap-IR can be applied in clinical ovarian cancer therapy in the near future.

3.
J Matern Fetal Neonatal Med ; 37(1): 2294691, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38146168

RESUMEN

OBJECTIVE: In recent years, several studies have reported an association between unsaturated fatty acids (UFAs) and the risk of developing preeclampsia; however, its exact causal effect is unclear. This study assessed the causal association between circulating UFAs and preeclampsia. METHODS: A two-sample Mendelian randomization (MR) study using publicly available genome-wide association study (GWAS) summary data for circulating UFA s (N = 114,999) and preeclampsia (N = 118,291) was performed. Single nucleotide polymorphisms (SNPs) significantly associated with exposure was selected as instrumental variables (IVs). The inverse variance weighted (IVW) test was used as the primary method for estimating causality in MR analysis, while MR pleiotropy residual sum and outlier (MR-PRESSO) and MR-Egger regression methods were used to assess horizontal pleiotropy. Cochran's Q test was used to evaluate heterogeneity among SNPs, and leave-one-out sensitivity analysis was used to determine the effect of individual SNPs on the results of the MR analysis. Bonferroni correction was used as a correction for multiple corrections. RESULTS: Two-sample MR analysis suggested that the ratio of monounsaturated fatty acids (MUFAs) to total fatty acids (OR 1.150, 95% CI 1.006-1.315, p = 0.041), the ratio of polyunsaturated fatty acids (PUFAs) to total fatty acids (OR 0.805, 95% CI 0.658-0.986, p = 0.036) and the ratio of PUFAs to MUFAs (OR 0.807, 95% CI 0.694-0.938, p = 0.005) were causally associated with preeclampsia. After Bonferroni correction, the causal association between the ratio of polyunsaturated to MUFAs and preeclampsia remained statistically different. CONCLUSIONS: This MR analysis provides evidence for a genetic causal association between circulating UFAs and preeclampsia.


Asunto(s)
Estudio de Asociación del Genoma Completo , Preeclampsia , Femenino , Humanos , Embarazo , Ácidos Grasos , Ácidos Grasos Insaturados , Análisis de la Aleatorización Mendeliana , Preeclampsia/genética
4.
BMC Complement Med Ther ; 23(1): 400, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37936097

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC), abbreviated as liver cancer, is one of the most common cancers in clinics. HCC has a wider spread and higher incidence due to its high malignancy and metastasis. In HCC, effective strategies to block cancer cell migration, invasion, and neovascularization need to be further studied. Consumption of flavonoid-rich Oroxylum indicum (OI) has been associated with multiple beneficial effects, including anti-inflammatory and anticancer properties, but the potential effects on HCC have not been thoroughly investigated. OBJECTIVE: In this study, we aimed to reveal the effect of OI on HCC and its potential mechanism through microfluidic technology. METHODS: We designed microfluidic chips for cell migration, invasion, and neovascularization to evaluate the effect of OI on HepG2 cells. To further explore the mechanism of its anti-liver cancer action, the relevant signaling pathways were studied by microfluidic chips, RT‒qPCR and immunofluorescence techniques. Compared to the control group, cell migration, invasion, and angiogenesis were significantly reduced in each administration group. According to the P53 and VEGF pathways predicted by network pharmacology, RT‒qPCR and immunofluorescence staining experiments were conducted. RESULTS: The results showed that OI upregulated the expression of Bax, P53 and Caspase-3 and downregulated the expression of Bcl-2 and MDM2. It has been speculated that OI may directly or indirectly induce apoptosis of HepG2 cells by regulating apoptosis-related genes. OI blocks the VEGF signaling pathway by downregulating the expression levels of VEGF, HIF-1α and EGFR and inhibits the migration and invasion of HepG2 cells and the formation of new blood vessels. CONCLUSION: Our findings suggest that OI may inhibit the migration, invasion, and neovascularization of HepG2 cells, and its regulatory mechanism may be related to the regulation of the P53 and VEGF pathways.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Microfluídica
5.
Heliyon ; 9(10): e21013, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37886749

RESUMEN

Objectives: The aim of this study is to understand the feelings and experiences of the main caregivers of temporary ostomy patien ts with Crohn's disease (CD). And explore the caregivers' inner feelings, to provide reference and basis for constructing the health education content of the main caregivers of CD patients with a temporary stoma. Methods: A qualitative descriptive approach was used to conduct an unstructured interview among 11 primary caregivers of CD patients with temporary enterostomy from the gastroenterology department of The Second Hospital of Nanjing. Participants were selected using a purposive sampling technique. Data were collected between July 2021 and September 2021. The interviews were audio recorded and then transcribed for a qualitative thematic analysis. Results: Five themes and accompanying subthemes were identified: (1) negative psychological experience (2) perceived caregiver burden (3) future uncertainty (4) disease benefit (5) insufficien support system. Conclusions: Study findings suggest that caregivers of CD temporary enterostomy patients have problems such as negative psychology, heavy caregiver burden, uncertain future, lack of support system, etc., but they also have positive experience of feeling of benefit from the disease, and are eager to obtain more disease information from more channels.Therefore, medical staff should improve their professionalism and health education capabilities, carry out diversified and targeted health education activities to reduce the burden of care, stimulate positive caregiver responses and help caregivers respond to and deal with caregiving problems in a timely and accurate manner.

6.
J Org Chem ; 88(20): 14540-14549, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37773964

RESUMEN

Density functional theory (DFT) calculations have been employed to investigate the mechanism of carboamination and diamination of unactivated alkenes mediated by Pd(IV) intermediates. Both reactions share a common Pd(IV) intermediate, serving as the starting point for either the carboamination or the diamination pathway. The formation of this Pd(IV) intermediate encompasses a transition state that substantially impacts the turnover frequency (TOF) of catalytic cycles, with an apparent activation free-energy barrier of 26.1 kcal mol-1. Carboamination of unactivated alkenes proceeds through the coordination of a toluene molecule, C-H activation, inner reductive elimination, and the separation of the carboamination product from this intermediate, while diamination of unactivated alkenes involves the formation of the ion nucleophile, SN2 attack, and the separation of the diamination product. A comparison of the free-energy profiles for carboamination and diamination of unactivated alkenes can elucidate the origin of the chemoselectivity, and Bader's atoms in molecules (AIM) wave function analyses have been performed to analyze the contributions of the outer C-N bonding in the diamination process.

7.
J Vis ; 23(8): 16, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37610734

RESUMEN

Coincidence anticipation (CA) refers to the ability to coordinate responses to the arrival of a moving object. This study investigates the neurobehavioral processes that underlie CA through the measurement of electroencephalography (EEG) recorded during a CA task on a 17-foot plastic rail with evenly spaced LED lights. Participants responded at the anticipated moment a sequence of successively lit LEDs coincided with a stationary target. Healthy young adult participants (Mage = 21) performed six blocks with movement at 20, 30, or 40 mph and the direction either inbound or outbound relative to the participant. Behavioral results demonstrated a main effect of speed and an interaction between speed and direction, with outbound motion producing early responses and inbound motion producing delayed responses that increased at greater speeds. EEG demonstrated characteristic P1, N2, and P3-like visual evoked potentials (VEPs). VEP amplitudes revealed a significant direction by channel interaction for the P1, indicative of more medial responses for inbound motion. Significant laterality differences were present in the N2, whereas the P3 component produced significant main effects and interactions of speed and direction. This novel combination of three-dimensional CA with EEG demonstrates systematic brain responses that are tuned for motion speed and sensitive to different egocentric motion patterns thereby shedding new light on the mechanism of human visual-motor control.


Asunto(s)
Encéfalo , Potenciales Evocados Visuales , Adulto Joven , Humanos , Electroencefalografía , Lateralidad Funcional , Voluntarios Sanos
8.
Front Robot AI ; 10: 1210217, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37547621

RESUMEN

Trunk-like continuum robots have wide applications in manipulation and locomotion. In particular, trunk-like soft arms exhibit high dexterity and adaptability very similar to the creatures of the natural world. However, owing to the continuum and soft bodies, their performance in payload and spatial movements is limited. In this paper, we investigate the influence of key design parameters on robotic performance. It is verified that a larger workspace, lateral stiffness, payload, and bending moment could be achieved with adjustments to soft materials' hardness, the height of module segments, and arrayed radius of actuators. Especially, a 55% increase in arrayed radius would enhance the lateral stiffness by 25% and a bending moment by 55%. An 80% increase in segment height would enlarge 112% of the elongation range and 70 % of the bending range. Around 200% and 150% increments in the segment's lateral stiffness and payload forces, respectively, could be obtained by tuning the hardness of soft materials. These relations enable the design customization of trunk-like soft arms, in which this tapering structure ensures stability via the stocky base for an impact reduction of 50% compared to that of the tip and ensures dexterity of the long tip for a relatively larger bending range of over 400% compared to that of the base. The complete methodology of the design concept, analytical models, simulation, and experiments is developed to offer comprehensive guidelines for trunk-like soft robotic design and enable high performance in robotic manipulation.

9.
J Consult Clin Psychol ; 91(10): 574-595, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37410398

RESUMEN

OBJECTIVE: Disadvantaged populations, including inhabitants of developing countries as well as racial/ethnic and sexual minorities in the United States, are disproportionally burdened by human immunodeficiency virus (HIV) infection, delayed HIV diagnosis, and unfavorable HIV-treatment outcomes. HIV interventions targeting single behaviors (e.g., testing) in these populations have shown to be efficacious at producing behavioral and clinical change but have been unable to eliminate the social health disparities associated with syndemics (i.e., a set of connected risks, interacting synergistically, and contributing to excess burden of disease in a population). METHOD: This meta-analysis of 331 reports (clusters; number of effect sizes [k] = 1,364) assessed whether multiple-behavior interventions that target clusters of syndemic risks are more efficacious for those in disadvantaged regions and social groups. RESULTS: Across the board, multiple-behavior interventions were more efficacious than single-behavior ones as well as passive control groups among samples from countries with lower log gross domestic product (GDP), lower Human Development Index (HDI), and lower Healthcare Access and Quality (HAQ) Index. CONCLUSIONS: Within the United States, the efficacy of multiple-behavior interventions was similar across different levels of representation of racial/ethnic and sexual minorities. The analyses used robust variance estimation with small-sample corrections to assess the differential effects of multiple-behavior interventions and Egger Sandwich test with the multilevel meta-analysis approach to detect selection biases. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Infecciones por VIH , Minorías Sexuales y de Género , Humanos , Estados Unidos/epidemiología , Sindémico , Infecciones por VIH/epidemiología , Infecciones por VIH/terapia , Terapia Conductista
10.
Sci Rep ; 13(1): 12116, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37495618

RESUMEN

Earthworms have entirely soft bodies mainly composed of circular and longitudinal muscle bundles but can handle the complexity of unstructured environments with exceptional multifunctionality. Soft robots are naturally appropriate for mimicking soft animal structures thanks to their inherent compliance. Here, we explore the new possibility of using this compliance to coordinate the actuation movements of single-type soft actuators for not only high adaptability but the simultaneous multifunctionality of soft robots. A cross-linked actuator coordination mechanism is proposed and explained with a novel conceptual design of a cross-linked network, characterization of modular coordinated kinematics, and a modular control strategy for multiple functions. We model and analyze the motion patterns for these functions, including grabbing, manipulation, and locomotion. This further enables the combination of simultaneous multi-functions with this very simple actuator network structure. In this way, a soft modular robot is developed with demonstrations of a novel continuous-transportation mode, for which multiple objects could be simultaneously transported in unstructured environments with either mobile manipulation or pick-and-place operation. A comprehensive workflow is presented to elaborate the cross-linked actuator coordination concept, analytical modeling, modular control strategy, experimental validation, and multi-functional applications. Our understanding of actuator coordination inspires new soft robotic designs for wider robotic applications.

11.
Sensors (Basel) ; 23(13)2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37447978

RESUMEN

This paper evaluates the potential application of Raman baselines in characterizing organic deposition. Taking the layered sediments (Stromatolite) formed by the growth of early life on the Earth as the research object, Raman spectroscopy is an essential means to detect deep-space extraterrestrial life. Fluorescence is the main factor that interferes with Raman spectroscopy detection, which will cause the enhancement of the Raman baseline and annihilate Raman information. The paper aims to evaluate fluorescence contained in the Raman baseline and characterize organic sedimentary structure using the Raman baseline. This study achieves spectral image fusion combined with mapping technology to obtain high spatial and spectral resolution fusion images. To clarify that the fluorescence of organic matter deposition is the main factor causing Raman baseline enhancement, 5041 Raman spectra were obtained in the scanning area of 710 µm × 710 µm, and the correlation mechanism between the gray level of the light-dark layer of the detection point and the Raman baseline was compared. The spatial distribution of carbonate minerals and organic precipitations was detected by combining mapping technology. In addition, based on the BI-IHS algorithm, the spectral image fusion of Raman fluorescence mapping and reflection micrograph, polarization micrograph, and orthogonal polarization micrograph are realized, respectively. A fusion image with high spectral resolution and high spatial resolution is obtained. The results show that the Raman baseline can be used as helpful information to characterize stromatolite organic sedimentary structure.


Asunto(s)
Algoritmos , Carbonatos , Compuestos Orgánicos , Espectrometría Raman/métodos
12.
Phys Chem Chem Phys ; 25(29): 19422-19426, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37455579

RESUMEN

DFT calculations of reaction mechanisms in solution have always been a hot topic, especially for transition-metal-catalyzed reactions, in which the traditional DFT-D3 method has been extensively employed. The overestimation of the dispersion from the traditional DFT-D3 method leads to a quite low activation free-energy barrier, so it is worth finding a proper way to deal with the dispersion for solution systems. The solvent-solute dispersion is also important for solution systems, and thus it should be calculated together with the solute dispersion. The newly generated solute-solute dispersion energy should be shared equally with the newly formed cavity between two interacting species; therefore, only half of the solute-solute and solvent-solute dispersion terms belong to the solute molecule. The detailed treatment of dispersion correction for solution systems has been fully addressed, and this method has been confirmed with the examples of ligand exchange reactions and catalytic reactions.

14.
Org Lett ; 25(22): 4150-4155, 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37252906

RESUMEN

A convenient and efficient approach was developed to synthesize α-Kdo O-glycosides based on the Tf2O/(p-Tol)2SO preactivation strategy using peracetylated Kdo thioglycoside as a donor. Under the optimized reaction conditions, several O-glycoside products, including α-(2 → 1)-, α-(2 → 2)-, α-(2 → 3)-, and α-(2 → 6)-Kdo products, were stereoselectively synthesized in high yields. Remarkably, a series of aromatic α-Kdo O-glycosides were first and successfully constructed in high yields. An SN2-like mechanism was revealed by DFT calculations and experimental results.


Asunto(s)
Glicósidos Cardíacos , Glicósidos , Glicosilación , Azúcares Ácidos , Lipopolisacáridos
15.
BMC Cancer ; 23(1): 256, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36941558

RESUMEN

OBJECTIVE: Currently, the association between smoking, alcohol, and coffee intake and the risk of ovarian cancer (OC) remains conflicting. In this study, we used a two-sample mendelian randomization (MR) method to evaluate the association of smoking, drinking and coffee consumption with the risk of OC and prognosis. METHODS: Five risk factors related to lifestyles (cigarettes per day, smoking initiation, smoking cessation, alcohol consumption and coffee consumption) were chosen from the Genome-Wide Association Study, and 28, 105, 10, 36 and 36 single-nucleotide polymorphisms (SNPs) were obtained as instrumental variables (IVs). Outcome variables were achieved from the Ovarian Cancer Association Consortium. Inverse-variance-weighted method was mainly used to compute odds ratios (OR) and 95% confidence intervals (Cl). RESULTS: The two-sample MR analysis supported the causal association of genetically predicted smoking initiation (OR: 1.15 per SD, 95%CI: 1.02-1.29, P = 0.027) and coffee consumption (OR: 1.40 per 50% increase, 95%CI: 1.02-1.93, P = 0.040) with the risk of OC, but not cigarettes per day, smoking cessation, and alcohol consumption. Subgroup analysis based on histological subtypes revealed a positive genetical predictive association between coffee consumption and endometrioid OC (OR: 3.01, 95%CI: 1.50-6.04, P = 0.002). Several smoking initiation-related SNPs (rs7585579, rs7929518, rs2378662, rs10001365, rs11078713, rs7929518, and rs62098013), and coffee consumption-related SNPs (rs4410790, and rs1057868) were all associated with overall survival and cancer-specific survival in OC. CONCLUSION: Our findings provide the evidence for a favorable causal association of genetically predicted smoking initiation and coffee consumption with OC risk, and coffee consumption is linked to a greater risk of endometrioid OC.


Asunto(s)
Carcinoma Endometrioide , Neoplasias Ováricas , Humanos , Femenino , Café/efectos adversos , Análisis de la Aleatorización Mendeliana/métodos , Estudio de Asociación del Genoma Completo , Fumar/efectos adversos , Fumar/epidemiología , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/genética , Factores de Riesgo , Carcinoma Epitelial de Ovario/genética , Etanol , Carcinoma Endometrioide/complicaciones , Polimorfismo de Nucleótido Simple , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/genética
16.
PLoS One ; 18(1): e0278689, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36656847

RESUMEN

Baseball is an international sport with participation from tens of thousands of people worldwide. In the United States, the Prospect Development Pipeline (PDP) is a collaborative effort between Major League Baseball and USA Baseball to establish a developmental pipeline leading to the professional draft. Players participating in the PDP undergo comprehensive evaluations that measure athletic performance, speed-of-processing, visual function, and on-field talent. The present study evaluated data from 1352 elite junior male PDP participants (aged 14 to 21) who signed informed consent, collected between 2017 and 2020, to identify latent abilities and their association with player specialization. Data were first subjected to Exploratory Factor Analysis (EFA) to reduce the 22 measured variables to a smaller set of latent abilities. The resulting factors were evaluated using multiple linear regression to predict each factor using age, height, weight, and position. EFA revealed a combination of physical and psychomotor skills accounting for 52% of the overall variance that grouped into four abilities: grip strength, functional vision, explosiveness, and rapid decision-making. Regression analyses demonstrated that these skills are associated with position assignments, controlling for age, weight, and height, and revealed that outfielders are the most explosive, infielders perform best on psychomotor measures, and catchers perform best on functional vision tests (ps < 0.001). These findings indicate skills that contribute to player specialization, providing new information about the developmental trajectory of junior elite baseball athletes that can be used for scouting and player development.


Asunto(s)
Rendimiento Atlético , Béisbol , Humanos , Masculino , Adolescente , Estados Unidos , Atletas , Especialización
17.
ACS Appl Mater Interfaces ; 15(2): 3317-3324, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36602990

RESUMEN

Zirconium carbide (ZrC), a novel representative of the MXene family, has attracted considerable interest because of its outstanding physicochemical properties and potential applications in optoelectronic devices. For improving its performance as an optical modulator for ultrashort lasers, there is a call to continue studying the nonlinear optical behavior of MXene ZrC. Herein, for the first time, MXene ZrC films were fabricated on fused silica by magnetron sputtering deposition technology and used as a saturable absorber (SA) optical modulator in a passive Q-switched Nd:YAG laser. The saturation absorption behaviors of the prepared ZrC films were characterized by the Z-scan method. Their morphology, band structure, damage threshold, carrier recovery time, and saturation absorption properties were analyzed. The experimental results show that the MXene ZrC SA films exhibit excellent nonlinear optical characteristics, with a saturation intensity of 48.4 MW/cm2, a large modulation depth of 6.9%, and an ultrashort recovery time of 2.72 ps. In addition, the damage threshold of MXene ZrC SA films was estimated to be greater than 0.2516 J/cm2. By integrating the ZrC SA film optical modulator into the oscillator of the Nd:YAG laser, we achieved stable operation of the Q-switched laser with a central wavelength at 1.06 µm, with the shortest pulse width of 78 ns. The results of this study demonstrate the potential use of MXene ZrC SA films as optical modulators in ultrashort lasers.

18.
Phys Chem Chem Phys ; 25(2): 913-931, 2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36519338

RESUMEN

DFT calculations of reaction mechanisms in solution have always been a hot topic, especially for transition-metal-catalyzed reactions. The calculation of solvation energy is performed using either the polarizable continuum model (PCM) or the universal solvation model SMD. The PCM calculation is very sensitive to the choice of atomic radii to form a cavity, where the self-consistent isodensity PCM (SCI-PCM) has been recognized as the best choice and our IDSCRF radii can provide a similar cavity. Moving from a gas-phase case to a solution case, dispersion energy and entropy should be carefully treated. The solvent-solute dispersion is also important in solution systems, and it should be calculated together with the solute dispersion. Only half of the solvent-solute dispersion energy from the PCM calculation belongs to the solute molecules to maintain a thermal equilibrium between a solute molecule and its cavity, similar to the treatment of electrostatic energy. Relative solute dispersion energy should also be shared equally with the newly formed cavity. The entropy change from a gas phase to a liquid phase is quite large, but the modern quantum chemistry programs can only calculate the gas-phase translational entropy based on the idea-gas equation. In this review, we will provide an operable method to calculate the solution translational entropy, which has been coded in our THERMO program.

19.
Rev Neurosci ; 34(3): 349-364, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-36310385

RESUMEN

The last decades have seen a rise in the use of transcranial direct current stimulation (tDCS) approaches to modulate brain activity and associated behavior. Concurrently, eye tracking (ET) technology has improved to allow more precise quantitative measurement of gaze behavior, offering a window into the mechanisms of vision and cognition. When combined, tDCS and ET provide a powerful system to probe brain function and measure the impact on visual function, leading to an increasing number of studies that utilize these techniques together. The current pre-registered, systematic review seeks to describe the literature that integrates these approaches with the goal of changing brain activity with tDCS and measuring associated changes in eye movements with ET. The literature search identified 26 articles that combined ET and tDCS in a probe-and-measure model and are systematically reviewed here. All studies implemented controlled interventional designs to address topics related to oculomotor control, cognitive processing, emotion regulation, or cravings in healthy volunteers and patient populations. Across these studies, active stimulation typically led to changes in the number, duration, and timing of fixations compared to control stimulation. Notably, half the studies addressed emotion regulation, each showing hypothesized effects of tDCS on ET metrics, while tDCS targeting the frontal cortex was widely used and also generally produced expected modulation of ET. This review reveals promising evidence of the impact of tDCS on eye movements and associated psychological function, offering a framework for effective designs with recommendations for future studies.


Asunto(s)
Fenómenos Fisiológicos del Sistema Nervioso , Estimulación Transcraneal de Corriente Directa , Humanos , Estimulación Transcraneal de Corriente Directa/métodos , Movimientos Oculares , Corteza Prefrontal/fisiología , Cognición/fisiología
20.
Soft Robot ; 10(2): 395-409, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36318818

RESUMEN

Soft actuators have shown great advantages in compliance and morphology matched for manipulation of delicate objects and inspection in a confined space. There is an unmet need for a soft actuator that can provide torsional motion to, for example, enlarge working space and increase degrees of freedom. Toward this goal, we present origami-inspired soft pneumatic actuators (OSPAs) made from silicone. The prototype can output a rotation of more than one revolution (up to 435°), more significant than its counterparts. Its rotation ratio ( = rotation angle/aspect ratio) is more than 136°, about twice the largest one in other literature. We describe the design and fabrication method, build the analytical model and simulation model, and analyze and optimize the parameters. Finally, we demonstrate the potentially extensive utility of the OSPAs through their integration into a gripper capable of simultaneously grasping and lifting fragile or flat objects, a versatile robot arm capable of picking and placing items at the right angle with the twisting actuators, and a soft snake robot capable of changing attitude and directions by torsion of the twisting actuators.

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