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1.
Artigo em Inglês | MEDLINE | ID: mdl-39144408

RESUMO

Objectives: We aimed to conduct a systematic review and meta-analysis to assess the value of image-enhanced endoscopy including blue laser imaging (BLI), linked color imaging, narrow-band imaging (NBI), and texture and color enhancement imaging to detect and diagnose gastric cancer (GC) compared to that of white-light imaging (WLI). Methods: Studies meeting the inclusion criteria were identified through PubMed, Cochrane Library, and Japan Medical Abstracts Society databases searches. The pooled risk ratio for dichotomous variables was calculated using the random-effects model to assess the GC detection between WLI and image-enhanced endoscopy. A random-effects model was used to calculate the overall diagnostic performance of WLI and magnifying image-enhanced endoscopy for GC. Results: Sixteen studies met the inclusion criteria. The detection rate of GC was significantly improved in linked color imaging compared with that in WLI (risk ratio, 2.20; 95% confidence interval [CI], 1.39-3.25; p < 0.01) with mild heterogeneity. Magnifying endoscopy with NBI (ME-NBI) obtained a pooled sensitivity, specificity, and area under the summary receiver operating curve of 0.84 (95 % CI, 0.80-0.88), 0.96 (95 % CI, 0.94-0.97), and 0.92, respectively. Similarly, ME-BLI showed a pooled sensitivity, specificity, and area under the curve of 0.81 (95 % CI, 0.77-0.85), 0.85 (95 % CI, 0.82-0.88), and 0.95, respectively. The diagnostic efficacy of ME-NBI/BLI for GC was evidently high compared to that of WLI, However, significant heterogeneity among the NBI studies still existed. Conclusions: Our meta-analysis showed a high detection rate for linked color imaging and a high diagnostic performance of ME-NBI/BLI for GC compared to that with WLI.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38808314

RESUMO

A 68-year-old man was admitted with hematochezia. Emergency computed tomography showed multiple diverticula throughout the colon. Initial colonoscopy on day 2 showed no active bleeding, but massive hematochezia on day 3 led to the performance of an emergency endoscopy. Substantial bleeding in the ileocecal area obscured the visual field, making it challenging to view the area around the bleeding site. Two endoscopic band ligations (EBLs) were applied at the suspected bleeding sites. Hemostasis was achieved without active bleeding after EBL. However, the patient developed lower right abdominal pain and fever (39.4°C) on day 6. Urgent computed tomography revealed appendiceal inflammation, necessitating emergency open ileocecal resection for acute appendicitis. Pathological examination confirmed acute phlegmonous appendicitis, with EBLs noted at the appendiceal orifice and on the anal side. This case illustrates the efficacy of EBL in managing colonic diverticular bleeding. However, it also highlights the risk of appendicitis due to EBL in cases of ileocecal hemorrhage exacerbated by poor visibility due to substantial bleeding. Endoscopists need to consider this rare but important complication when performing EBL in similar situations.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38817687

RESUMO

Objective: A newly launched endoscopy system (EVIS X1, CV-1500; Olympus) is equipped with texture and color enhancement imaging (TXI). We aimed to investigate the efficacy of TXI for the visibility and diagnostic accuracy of non-polypoid colorectal lesions. Methods: We examined 100 non-polypoid lesions in 42 patients from the same position, angle, and distance of the view in three modes: white light imaging (WLI), narrow-band imaging (NBI), and TXI. The primary outcome was to compare polyp visibility in the three modes using subjective polyp visibility score and objective color difference values. The secondary outcome was to compare the diagnostic accuracy without magnification. Results: Overall, the visibility score of TXI was significantly higher than that of WLI (3.7 ± 1.1 vs. 3.6 ± 1.1; p = 0.008) and lower than that of NBI (3.7 ± 1.1 vs. 3.8 ± 1.1; p = 0.013). Color difference values of TXI were higher than those of WLI (11.5 ± 6.9 vs. 9.1 ± 5.4; p < 0.001) and lower than those of NBI (11.5 ± 6.9 vs. 13.1 ± 7.7; p = 0.002). No significant differences in TXI and NBI (visibility score: 3.7 ± 1.0 vs. 3.8 ± 1.1; p = 0.833, color difference values: 11.6 ± 7.1 vs. 12.9 ± 8.3; p = 0.099) were observed for neoplastic lesions. Moreover, the diagnostic accuracy of TXI was significantly higher than that of NBI (65.5% vs. 57.6%, p = 0.012) for neoplastic lesions. Conclusions: TXI demonstrated higher visibility than that of WLI and lower than that of NBI. Further investigations are warranted to validate the performance of the TXI mode comprehensively.

4.
Front Physiol ; 15: 1427094, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39224206

RESUMO

Introduction: Electrostatic binding of deoxyhemoglobin (Hb) to cytoplasmic domain of band 3 anion transport protein occurs as part of the glycolytic regulation in red blood cells (RBCs). Hb oxidation intermediates not only impact RBC's oxygenation but also RBC's membrane through the interaction with band 3. It is not known however whether these critical pathways undergo changes during the storage of RBCs. Methods and Results: Oxygen parameters of fresh blood showed a sigmoidal and cooperative oxygen dissociation curve (ODC) for the first week of storage. This was followed by a large drop in oxygen affinity (P50) (from 30 to 20 mmHg) which remained nearly unchanged with a slight elevation in Bohr coefficients and a significant drop in extracellular acidification rates (ECAR) at the 42-day storage. Oxidation of Hb increased with time as well as the formation of a highly reactive ferryl Hb under oxidative stress conditions. Ferryl Hb interacted avidly with RBC's membrane's band 3, but to lesser extent with old ghost RBCs. Discussion: The observed alterations in RBC's oxygen binding may have been affected by the alterations in band 3's integrity which are largely driven by the internal iron oxidation of Hb. Restoring oxygen homeostasis in stored blood may require therapeutic interventions that target changes in Hb oxidation and membrane changes.

5.
Orthop Surg ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223447

RESUMO

OBJECTIVE: Femoral head necrosis is a challenging condition in orthopaedics, and the occurrence of collapse is an important factor affecting the prognosis of femoral head necrosis. Sclerosis bands are known to influence the collapse of the femoral head, yet there is a lack of research on the biomechanical role of sclerosis bands in non-vascularized fibular grafting surgery. This study aims to evaluate the biomechanical impact of sclerosis bands in femoral head necrosis and their role in non-vascularized fibular grafting surgery (NVFG) using finite element analysis. METHODS: We constructed 11 finite element models based on CT scan data of a normal hip joint, simulating different sclerosis band thicknesses and defect scenarios. The models were analyzed for changes in femoral head displacement and von Mises stress. We constructed a hip joint model based on CT data from a normal hip joint, and after reconstruction, assembly, and optimization using 3-matic. We created five groups consisting of 11 finite element analysis models of the hip joint. Mesh partitioning and mechanical parameter settings were performed in ANSYS. The changes and differences in femoral head displacement and von Mises stress of these models were analyzed. RESULTS: Increasing sclerosis band thickness led to reduced peak displacement of the femoral head by 28.6%, 42.9%, and 47.6%, and increased surface von Mises stress by 28.3%, 13.8%, and 13.0%, respectively. Post-surgery, peak displacement decreased in all groups compared to pre-surgery levels. Increasing sclerosis band thickness post-surgery resulted in decreased maximum von Mises stress of the femoral head by 13.9%, 3.0%, and 8.1%. Defect volume in the defect groups correlated with increased peak displacement of the femoral head by 10.0%, 30.0%, and 100.0%, and increased surface maximum von Mises stress of the femoral head by 9.3%, 14.0%, and 15.1%. CONCLUSION: Sclerosis band formation exacerbates von Mises stress concentration on the femoral head surface. However, thicker sclerosis bands improve post-NVFG stability and mechanical performance. Larger anterior lateral sclerosis band defects significantly compromise postoperative stability, increasing the risk of collapse. Protecting the anterior lateral sclerosis band during NVFG surgery is crucial.

6.
Nano Lett ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225119

RESUMO

Prolonging hot carrier cooling, a crucial factor in optoelectronic applications, including hot carrier photovoltaics, presents a significant challenge. High-energy band-nesting excitons within parallel bands offer a promising and underexplored avenue for addressing this issue. Here, we exploit an exceptional D exciton cooling prolongation of 2 to 3 orders of magnitude compared to sub-picosecond in typical transition metal dichalcogenides (TMDs) owing to the complex Coulomb environment and the sequential and mismatch-valley relaxation. Simultaneously, the intervalley scattering upconversion of band-edge excitons with the slow D exciton formation in the metastable Γ valley/hill also reduces the cooling rate. We successfully extract D and C excitons as hot carriers through integrating with various thicknesses of TiOx, achieving the highest efficiency of 98% and 85% at a Ti thickness of 2 nm. Our findings highlight the potential of band-nesting excitons for extending hot carrier cooling time, paving the way for advancements in hot carrier-based optoelectronic devices.

7.
Artigo em Inglês | MEDLINE | ID: mdl-39230796

RESUMO

PURPOSE: To address the clinical need for totally implantable mechanical circulatory support devices, Bionet Sonar is developing a novel Ultrasonic Transcutaneous Energy Transmission (UTET) system that is designed to eliminate external power and/or data communication drivelines. METHODS: UTET systems were designed, fabricated, and pre-clinically tested using a non-clinical HeartWare HVAD in static and dynamic mock flow loop and acute animal models over a range of pump speeds (1800, 2400, 3000 RPM) and tissue analogue thicknesses (5, 10, 15 mm). RESULTS: The prototypes demonstrated feasibility as evidenced by meeting/exceeding function, operation, and performance metrics with no system failures, including achieving receiver (harvested) power exceeding HVAD power requirements and data communication rates of 10kB/s and pump speed control (> 95% sensitivity and specificity) for all experimental test conditions, and within healthy tissue temperature range with no acute tissue damage. CONCLUSION: During early-stage development and testing, engineering challenges for UTET size reduction and stable and safe operation were identified, with solutions and plans to address the limitations in future design iterations also presented.

9.
J Colloid Interface Sci ; 678(Pt B): 313-324, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39245021

RESUMO

The water pollution caused by the abuse of antibiotics has significant harmful effects on the environment and human health. The photo-Fenton process is currently the most effective method for removing antibiotics from water, but it encounters challenges such as inadequate response to visible light, low yield and utilization of photogenerated electrons, and slow electron transport. In this study, spin state regulation was introduced into the photo-Fenton process, and the spin state of Co3+ was regulated through Ce displacement doping. The intermediate-spin state Ce-LaCoO3 could degrade 91.6 % of tetracycline within 120 min in the photo-Fenton system, which is 15.2 % higher than that of low-spin state LaCoO3. The improved degradation effect is attributed to the reasons that Ce-LaCoO3 in the intermediate-spin state have lower band gap, better charge transfer ability, and stronger adsorption capacity of H2O2, which can accelerate the redox cycle of Co2+/Co3+ and promote the generation of ·OH. This study presents a unique strategy for synthesizing efficient photo-Fenton materials to treat antibiotic wastewater effectively.

10.
Sci Rep ; 14(1): 20724, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237527

RESUMO

First-principles calculations engaging density functional theory (DFT) are employed to systematically study the optical characteristics of monolayer and bilayer boron nitride (BN) triphenylene-graphdiyne (Tp-BNyne) structures featuring varying lengths of C-chains. The thermal stability of Tp-BNyne structures at temperatures up to 1000 K is verified. The weak van der Waals interactions due to the small binding energies and significant interlayer distances maintain the cohesion between the layers. The investigation revealed that all Tp-BNyne structures under examination exhibit semiconductor behavior with a band gap in the range of 0.97-2.74 eV. The bilayer configurations demonstrated a narrower energy band gap in comparison to the monolayer ones. Increasing the length of C-chains leads to a reduction in the energy band gap. Delving into the optical behavior of Tp-BNyne structures under photon incidence with parallel and perpendicular polarizations, a distinct anisotropy in the optical characteristics of Tp-BNyne is revealed. The static dielectric constant increases and the optical band gap decreases with increasing C-chain length. The absorption coefficients of monolayer and bilayer Tp-BNyne structures, on the order of 107/m, demonstrate that these sheets can effectively absorb light in the visible and ultraviolet regions. These findings present Tp-BNyne sheets as promising candidates for use in photovoltaic devices to convert sunlight into electrical current, as well as for designing optical devices for ultraviolet protection. Additionally, Tp-BNyne structures are transparent materials, especially in the high-energy range.

11.
Artigo em Inglês | MEDLINE | ID: mdl-39219097

RESUMO

Efficient and precise calculations of thermal transport properties and figures of merit, alongside a deep comprehension of thermal transport mechanisms, are essential for the practical utilization of advanced thermoelectric materials. In this study, we explore the microscopic processes governing thermal transport in the distinguished crystalline material Tl9SbTe6 by integrating a unified thermal transport theory with machine learning-assisted self-consistent phonon calculations. Leveraging machine learning potentials, we expedite the analysis of phonon energy shifts, higher-order scattering mechanisms, and thermal conductivity arising from various contributing factors, such as population and coherence channels. Our finding unveils an exceptionally low thermal conductivity of 0.31 W m-1 K-1 at room temperature, a result that closely correlates with experimental observations. Notably, we observe that the off-diagonal terms of heat flux operators play a significant role in shaping the overall lattice thermal conductivity of Tl9SbTe6, where the ultralow thermal conductivity resembles that of glass due to limited group velocities. Furthermore, we achieve a maximum ZT value of 3.17 in the c-axis orientation for p-type Tl9SbTe6 at 600 K and an optimal ZT value of 2.26 in the a-axis and b-axis direction for n-type Tl9SbTe6 at 500 K. The crystalline Tl9SbTe6 not only showcases remarkable thermal insulation but also demonstrates impressive electrical properties owing to the dual-degeneracy phenomenon within its valence band. These results not only elucidate the underlying reasons for the exceptional thermoelectric performance of Tl9SbTe6 but also suggest potential avenues for further experimental exploration.

12.
PeerJ ; 12: e17839, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39221286

RESUMO

Background: The objective of this study was to compare and analyze the representative opening and closing movement of Tai Chi elastic band exercise with the reverse fly movement of elastic band resistance training. The aim was to explore the biomechanical differences between the two exercises and provide theoretical support for the application of Tai Chi elastic band exercise in health intervention. Methods: A total of 26 male participants were recruited and randomly divided into two groups in a 1:1 ratio. There were 13 participants in each Tai Chi elastic band exercise group and elastic band resistance training group. Both groups of participants used an elastic band to perform movement in the experiment. Experimental data were collected using the Vicon infrared motion capture system and Delsys surface EMG system. The AnyBody software was utilized to simulate the creation of a musculoskeletal model for both exercises. Result: The study found that the Tai Chi elastic band exercise group exhibited smaller horizontal abduction angle and flexion angle of the shoulder joint, as well as normalized RMS of the anterior deltoid and triceps brachii, compared to the elastic band resistance training group (P < 0.01); the Tai Chi elastic band exercise group exhibited greater elbow flexion angle, elbow flexion torque, and muscle strength of the infraspinatus, coracobrachialis, biceps brachii, brachialis and brachioradialis, compared to the elastic band resistance training group (P < 0.01); the Tai Chi elastic band exercise group exhibited smaller horizontal abduction angular velocity of the shoulder joint and a lower normalized RMS of the posterior deltoid, compared to the elastic band resistance training group (P < 0.05). Conclusion: (1) The opening and closing movement of Tai Chi elastic band exercise is characterized by a large elbow flexion angle, a small shoulder joint horizontal angle and flexion angle, and a slow and uniform speed of movement. The reverse fly movement of elastic band resistance training is characterized by a large horizontal abduction angle of the shoulder joint, a large flexion angle of the shoulder joint, a small flexion angle of the elbow joint, and a fast and uneven speed. (2) The opening and closing movement exerts a greater torque on the elbow flexion, while the reverse fly movement exerts a greater torque on the shoulder joint horizontal abduction and external rotation. (3) The opening and closing movement provide greater stimulation to the infraspinatus, coracobrachialis, and elbow flexor, while the reverse fly movement provides greater stimulation to the posterior deltoid, anterior deltoid, subscapularis, and elbow extensor. In summary, the variation in joint angle, joint angular velocity, and hand position could be the factor contributing to the differences in joint torque and muscle activity between the opening and closing movement of Tai Chi elastic band exercise and the reverse fly movement of elastic band resistance training.


Assuntos
Amplitude de Movimento Articular , Treinamento Resistido , Tai Chi Chuan , Humanos , Masculino , Treinamento Resistido/métodos , Tai Chi Chuan/métodos , Fenômenos Biomecânicos/fisiologia , Amplitude de Movimento Articular/fisiologia , Adulto , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Articulação do Ombro/fisiologia , Eletromiografia , Movimento/fisiologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-39239968

RESUMO

It is, in fact, inevitable for steel to be covered with a layer of iron oxides and/or peroxides on its surface. However, knowledge of its existence and functionality for tribological behaviors is usually ignored. Herein, covalent-organic framework nanomaterials (CONs) composed of three well-screened acceptors and a donor through the imide linkage were fabricated to explore their lubrication performances. The results indicate that the energy-level matching between CONs and iron oxides or peroxides leads to the formation of a Z-scheme heterojunction structure at the rubbing interface. Also, the friction produces an internal electric field in the heterojunction, which drives the negative atomic/ionic species from the sliding interface to immigrate into the pore of CONs and resettle inside to engender the pinning effects, producing a fixed lubrication layer. Synchronously, it also attracts the free CONs in the base oil to form an easy-shear lubrication layer assembling onto the fixed one, producing a lubrication film with two layered configurations. Finally, the unique lubrication film, despite its thickness of a dozen nanometers, still exhibits impressive friction reduction and antiwear. This finding will inspire the technology to utilize the intrinsic surface nature of steel materials to exploit lubricant additives or modulate tribological behaviors.

14.
Artigo em Inglês | MEDLINE | ID: mdl-39235951

RESUMO

We theoretically identify the ScSeI monolayer as a promising new 2D material for photocatalysis through first-principles calculations. The most notable feature is the significant difference in carrier mobility, with electron mobility in the horizontal direction being 20.66 times higher than hole mobility, minimizing electron-hole recombination. The ScSeI monolayer exhibits a bandgap of 2.51 eV, with the valence band maximum at -6.37 eV and the conduction band minimum at -3.86 eV, meeting the requirements for water splitting. Phosphorus doping lowers the Gibbs free energy by 1.63 eV, enhancing the catalytic activity. The ScSeI monolayer achieves a hydrogen production efficiency of 17%, surpassing the commercial threshold of 10% and shows excellent mechanical, thermal, and dynamic stability, indicating feasibility for experimental synthesis and practical application. Additionally, the monolayer maintains its photocatalytic properties under tensile strain (-6% to 6%) and in aqueous environments, reinforcing its potential as an effective photocatalyst. Based on these findings, we believe the ScSeI monolayer is a highly promising photocatalyst.

15.
Cureus ; 16(8): e66140, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39233952

RESUMO

Olecranon fractures are common in orthopedic wards and can be traumatic or pathological in origin. There are very few cases of bilateral olecranon fractures without any associated injuries to the long bones in the literature. We present a unique case of a young 21-year-old male who has an isolated bilateral olecranon fracture following a road traffic accident. The patient had a closed fracture of the ulna on both sides without any associated injuries or neurovascular compromise. Since the patient was young and had good muscle strength preoperatively, we planned fixation of both sides. The patient underwent open reduction and internal fixation with tension band wiring on the right side, which was his dominant side. The left side was operated on by open reduction and internal fixation with an anatomical plate. The patient was started on elbow range of motion on the right side from the second postoperative day and started basic activities such as having food independently by the 10th day postoperatively. The physiotherapy was continued in a stepwise manner, and by the sixth week, the patient had a full range of motion on both sides. The patient had resumed his activities of daily living independently by the sixth week following the surgery. Such cases are rare, and a case-based management plan must be devised for each patient, considering contributing factors such as age, bone quality, osteoporosis, underlying medical comorbidities, functional demands, and muscle strength. We demonstrated a good clinical and radiological outcome by using tension band wiring on the dominant side with a stable olecranon fracture and plating done on the non-dominant side, which had an unstable displaced olecranon fracture.

16.
Sci Rep ; 14(1): 20507, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227645

RESUMO

In this study, a high-isolation dual-band (28/38 GHz) multiple-input-multiple-output (MIMO) antenna for 5G millimeter-wave indoor applications is presented. The antenna consists of two interconnected patches. The primary patch is connected to the inset feed, while the secondary patch is arc-shaped and positioned over the main patch, opposite to the feed. Both patches function in the lower 28 GHz band, while the primary patch is accountable for inducing the upper 38 GHz band. An expedited trust-region (TR) algorithm is employed to optimize the dimensions of the antenna components, ensuring the antenna operates efficiently with high reflection at both bands. The antenna demonstrates a gain exceeding 7 dBi at both frequencies. An array of four antennas is configured orthogonally to create a MIMO system with isolation surpassing 19 dB. The isolation is further enhanced through the addition of a circular parasitic patch at the front and modifications made to the ground. The TR method is employed again to optimize their parameters and achieve the desired isolation, exceeding 32 dB at both bands. The MIMO system demonstrates outstanding diversity performance at both frequencies, characterized by low values of the envelope correlation coefficient (ECC) (< 10 - 4), channel capacity loss (CCL) (< 0.03 bit/s/Hz), and total active reflection coefficient (TARC) (< - 10 dB). Additionally, it secures a diversity gain (DG) exceeding 9.99 dB. The MIMO system is manufactured and tested, showing good alignment between simulation and measurement data for all performance metrics.

17.
Adv Mater ; : e2410464, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235583

RESUMO

The interfacial management in perovskite solar cells (PSCs), including mitigating the carrier transport barrier and suppressing non-radiative recombination, still remains a significant challenge for efficiency and stability enhancement. Herein, by screening a family of fluorine (F) terminated dual-site organic dipole molecules, the study aims to gain insight into the molecular dipole array toward tunable interfacial field. Both experimental and theoretical results reveal that these functional interfacial dipole molecules can effectively anchor on perovskite surface through Lewis acid-base interaction. In addition, the tailored side-chain with terminated F atoms allows for altering and constructing a well matched perovskite/Spiro-OMeTAD interfacial contact. As a result, the inserting dual-site organic dipole array effectively modulates the interface to deliver a gradient energy level alignment, facilitating carrier extraction and transport. The optimal dual-site dipole trifluoro-methanesulfonamide mediated N-i-P PSCs achieve the highest efficiency of 25.47%, together with enhanced operational stability under 1000 h of the simulated 1-sun illumination exposure. These findings are believed to provide insight into the design of dual-site molecular dipole with sufficient interfacial tunability for perovskite-based optoelectronic devices.

18.
Small ; : e2402668, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235584

RESUMO

Photodetectors are one of the most critical components for future optoelectronic systems and it undergoes significant advancements to meet the growing demands of diverse applications spanning the spectrum from ultraviolet (UV) to terahertz (THz). 2D materials are very attractive for photodetector applications because of their distinct optical and electrical properties. The atomic-thin structure, high carrier mobility, low van der Waals (vdWs) interaction between layers, relatively narrower bandgap engineered through engineering, and significant absorption coefficient significantly benefit the chip-scale production and integration of 2D materials-based photodetectors. The extremely sensitive detection at ambient temperature with ultra-fast capabilities is made possible with the adaptability of 2D materials. Here, the recent progress of photodetectors based on 2D materials, covering the spectrum from UV to THz is reported. In this report, the interaction of light with 2D materials is first deliberated on in terms of optical physics. Then, various mechanisms on which detectors work, important performance parameters, important and fruitful fabrication methods, fundamental optical properties of 2D materials, various types of 2D materials-based detectors, different strategies to improve performance, and important applications of photodetectors are discussed.

19.
Brain Lang ; 256: 105463, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39243486

RESUMO

We investigated how neural oscillations code the hierarchical nature of stress rhythms in speech and how stress processing varies with language experience. By measuring phase synchrony of multilevel EEG-acoustic tracking and intra-brain cross-frequency coupling, we show the encoding of stress involves different neural signatures (delta rhythms = stress foot rate; theta rhythms = syllable rate), is stronger for amplitude vs. duration stress cues, and induces nested delta-theta coherence mirroring the stress-syllable hierarchy in speech. Only native English, but not Mandarin, speakers exhibited enhanced neural entrainment at central stress (2 Hz) and syllable (4 Hz) rates intrinsic to natural English. English individuals with superior cortical-stress tracking capabilities also displayed stronger neural hierarchical coherence, highlighting a nuanced interplay between internal nesting of brain rhythms and external entrainment rooted in language-specific speech rhythms. Our cross-language findings reveal brain-speech synchronization is not purely a "bottom-up" but benefits from "top-down" processing from listeners' language-specific experience.

20.
J Colloid Interface Sci ; 678(Pt A): 1087-1098, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39241470

RESUMO

Prussian blue analogs (PBAs) have attracted extensive attention in the field of aqueous organic degradation due to the tremendous potential for peroxydisulfate (PDS) activation. However, the relationship between the d-band center of the catalyst and the activation behavior of PDS remained largely unexplored. Herein, a series of Fe-Co PBAs-based catalysts with different Fe/Co ratios (Fe-Co PBAs-1 = 1: 0.52; Fe-Co PBAs-2 = 1: 1.21, and Fe-Co PBAs-3 = 1: 1.48) have been prepared by a facile hydrothermal procedure and subsequent acid treatment (Fe-Co PBAs-xH). The as-prepared Fe-Co PBAs-xH exhibited superior PDS activation performance and excellent recyclability in the degradation of methylene blue (MB). Density functional theory calculations revealed that the electron-occupied state of the Fe-Co PBAs was shifted to the Fermi level, indicating a strong interaction and easier electron transfer. Moreover, the d-band center of Fe-Co PBAs was upshifted relative to that of Fe PBAs, suggesting easier adsorption of MB and PDS, which was beneficial to enhancing catalytic activation and subsequent dissociation. Radicals such as •OH, 1O2, O2•-, and SO4•- were determined by the radical quenching experiment and electron paramagnetic resonance (EPR) testing in the Fe-Co PBAs-3H/PDS system, and the order of MB degradation by the free active radical is •OH > 1O2 > O2•- > SO4•-. The degradation pathway and potential ecotoxicity of MB and its intermediates were also studied. This work can provide new insights to construct the efficient catalysts for the activation of PDS and the degradation of organic pollutants.

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