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1.
Artículo en Inglés | MEDLINE | ID: mdl-38715897

RESUMEN

Objectives: Cold snare polypectomy (CSP) is widely performed for small colorectal polyps. However, small colorectal polyps sometimes include high-grade adenomas or carcinomas that require endoscopic resection with electrocautery. This study aimed to evaluate the efficacy and safety of a novel resection technique, hot snare polypectomy with low-power pure-cut current (LPPC-HSP) for small colorectal polyps, compared with CSP and conventional endoscopic mucosal resection (EMR). Methods: Records of patients who underwent CSP, EMR, or LPPC-HSP for nonpedunculated colorectal polyps less than 10 mm between April 2021 and March 2022 were retrospectively evaluated. We analyzed and compared the treatment outcomes of CSP and EMR with those of LPPC-HSP using propensity score matching. Results: After propensity score matching of 396 pairs, an analysis of CSP and LPPC-HSP indicated that LPPC-HSP had a significantly higher R0 resection rate (84% vs. 68%; p < 0.01). Delayed bleeding was observed in only two cases treated with CSP before matching. Perforation was not observed with either treatment. After propensity score matching of 176 pairs, an analysis of EMR and LPPC-HSP indicated that their en bloc and R0 resection rates were not significantly different (99.4% vs. 100%, p = 1.00; 79% vs. 81%, p = 0.79). Delayed bleeding and perforation were not observed with either treatment. Conclusions: The safety of LPPC-HSP was comparable to that of CSP. The treatment outcomes of LPPC-HSP were comparable to those of conventional EMR for small polyps. These results suggest that this technique is a safe and effective treatment for nonpedunculated polyps less than 10 mm.

2.
Front Neurosci ; 18: 1406135, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39221007

RESUMEN

Background: Transcutaneous Vagal Nerve Stimulation (tVNS) has been used as a promising noninvasive neuromodulation technique for the treatment of various systems.The aim of this study was to analyze the research hotspots and future directions of tVNS in the 21st century by using bibliometric methods. Methods: The study object was the literature related to tVNS from the Web of Science database from 2000 to May 2024. In order to measure and analyze the number of literature issuance, institutions, authors, countries, keywords, co-citations, and journals of publication, we used VOSviewer, Citespace, Bibliometrix R-package, and Scimago Graphica software. A narrative review of the current research content of tVNS was conducted to gain a better understanding of the current state of the field. Results: A total of 569 papers were included in the study. The results show that from 2000 to 2024, the number of publications shows an increasing trend year by year, involving a total of 326 research institutions. The United States, China, and Germany are the major research centers. The study identified 399 keywords, which roughly formed 11 natural clusters, revealing that the current hotspots of related research are mainly reflected in 3 areas: intervention efficacy on nervous system diseases, mechanism of action of tVNS, and stimulation mode of tVNS. The top 10 most cited references focus on research into the mechanism of action of tVNS. Conclusion: The efficacy and safety of tVNS have been confirmed in previous studies, but a standardized tVNS treatment protocol has not yet been developed, and most clinical studies have small sample sizes and lack multicenter and multidisciplinary collaboration. Currently, tVNS is used in the treatment of neurological diseases, psychiatric diseases, cardiovascular diseases, and some autoimmune diseases. It is expected that future research in this field will continue to focus on the application of tVNS in central nervous system diseases and the exploration of related mechanisms, and at the same time, with the rise of non-invasive neuromodulation technology, the application of tVNS in other diseases also has great potential for development.

3.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(4): 507-512, 2024 Aug.
Artículo en Chino | MEDLINE | ID: mdl-39223015

RESUMEN

Objective To understand the current situation and influencing factors of kindergarten teachers' participation in training for preschool sex education in Luzhou city,and provide a basis for improving the sex education literacy of kindergarten teachers in the future. Methods A multi-stage stratified cluster sampling method was adopted,and a questionnaire survey was conducted from December 2021 to January 2022 on the knowledge,attitude,and practice of preschool sex education among all the teachers in 24 kindergartens in Luzhou city. Results Among the 461 teachers,43.0% had participated in lectures/courses/training activities related to preschool sex education;99.1% hoped to participate in lectures/courses/training activities related to preschool sex education;82.6% learned about child sexual knowledge through school education;75.5% expressed the hope to learn about child sexual knowledge through expert training.The results of multivariate Logistic regression showed that except private kindergartens as an inhibiting factor (OR=0.57,95%CI=0.37-0.87,P=0.008),high monthly income (OR=3.52,95%CI=1.13-9.30,P=0.011),more ways to know about sex education knowledge (OR=2.87,95%CI=1.76-4.70,P<0.001),and social support (OR=1.58,95%CI=1.04-2.38, P=0.030) were promoting factors for teachers to participate in the training for preschool sex education. Conclusion The kindergarten teachers presented a participation rate but a high demand for the training for preschool sex education.They mainly obtain the sex education knowledge from school education.The nature of kindergarten,monthly income of teachers,social support situation,and ways of understanding sex education knowledge are the key factors influencing the teachers' participation in the training for preschool sex education.


Asunto(s)
Maestros , Educación Sexual , Humanos , Encuestas y Cuestionarios , Educación Sexual/métodos , Preescolar , Femenino , Masculino , Adulto , Conocimientos, Actitudes y Práctica en Salud , Formación del Profesorado/métodos , China
4.
Angew Chem Int Ed Engl ; : e202414234, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225452

RESUMEN

Manipulating the atomic structure of the catalyst and tailoring the dissociative water-hydrogen bonding network at the catalyst-electrolyte interface is essential for propelling alkaline hydrogen evolution reactions (HER) and hydrazine oxidation reaction (HzOR), but remains a great challenge. Herein, we constructed an advanced a-RuMo/NiMoO4/NF heterogeneous electrocatalysts with amorphous RuMo alloy nanoclusters anchored to amorphous NiMoO4 skeletons on Ni foam by a heteroatom implantation strategy. Theoretical calculations and in-situ Raman tests show that the amorphous and alloying structure of a-RuMo/NiMoO4/NF not only induces the directional evolution of interfacial H2O, but also lowers the d-band center (from -0.43 to -2.22 eV) of a-RuMo/NiMoO4/NF, the Gibbs free energy of hydrogen adsorption (ΔGH*, from -1.29 to -0.06 eV), and the energy barrier of HzOR (ΔGN2(g) = 1.50 eV to ΔGN2* = 0.47 eV). Profiting from these favorable factors, the a-RuMo/NiMoO4/NF exhibits excellent electrocatalytic performances, especially at large current densities, with an overpotential of 13 and 129 mV to reach 10 and 1000 mA cm-2 for HER. While for HzOR, it needs only -91 and 276 mV to deliver 10 and 500 mA cm-2, respectively. Further, the constructed a-RuMo/NiMoO4/NF||a-RuMo/NiMoO4/NF electrolyzer demands only 7 and 420 mV to afford 10 and 500 mA cm-2.

5.
J Neurosci Res ; 102(9): e25378, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39225477

RESUMEN

This study investigated whether the electric field magnitude (E-field) delivered to the left dorsolateral prefrontal cortex (L-DLPFC) changes resting-state brain activity and the L-DLPFC resting-state functional connectivity (rsFC), given the variability in tDCS response and lack of understanding of how rsFC changes. Twenty-one healthy participants received either 2 mA anodal or sham tDCS targeting the L-DLPFC for 10 min. Brain imaging was conducted before and after stimulation. The fractional amplitude of low-frequency fluctuation (fALFF), reflecting resting brain activity, and the L-DLPFC rsFC were analyzed to investigate the main effect of tDCS, main effect of time, and interaction effects. The E-field was estimated by modeling tDCS-induced individual electric fields and correlated with fALFF and L-DLPFC rsFC. Anodal tDCS increased fALFF in the left rostral middle frontal area and decreased fALFF in the midline frontal area (FWE p < 0.050), whereas sham induced no changes. Overall rsFC decreased after sham (positive and negative connectivity, p = 0.001 and 0.020, respectively), with modest and nonsignificant changes after anodal tDCS (p = 0.063 and 0.069, respectively). No significant differences in local rsFC were observed among the conditions. Correlations were observed between the E-field and rsFC changes in the L-DLPFC (r = 0.385, p = 0.115), left inferior parietal area (r = 0.495, p = 0.037), and right lateral visual area (r = 0.683, p = 0.002). Single-session tDCS induced resting brain activity changes and may help maintain overall rsFC. The E-field in the L-DLPFC is associated with rsFC changes in both proximal and distally connected brain regions to the L-DLPFC.


Asunto(s)
Estudios Cruzados , Corteza Prefontal Dorsolateral , Imagen por Resonancia Magnética , Estimulación Transcraneal de Corriente Directa , Humanos , Estimulación Transcraneal de Corriente Directa/métodos , Masculino , Femenino , Adulto , Adulto Joven , Corteza Prefontal Dorsolateral/fisiología , Vías Nerviosas/fisiología , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Mapeo Encefálico
6.
Clin Rehabil ; : 2692155241278949, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39257067

RESUMEN

OBJECTIVE: To compare the efficacy of interferential current (IFC) therapy combined with quadriceps strengthening exercise versus sham IFC plus exercise for pain relief and functional improvement in patients with knee osteoarthritis. STUDY DESIGN: Double-blind randomised controlled trial. SETTING: Outpatient rehabilitation clinic. SUBJECTS: Knee osteoarthritis patients aged 50-85 years with a pain score ≥4/10. METHODS: One hundred forty-four participants were randomly allocated into the study and control groups. The study group received 20 min of IFC therapy (carrier frequency: 4000 Hz, beat frequency: 100 Hz) five times per week for three weeks, while the control group received sham IFC following the same protocol, followed by 10 min of exercise in both groups. Outcome measures included Numeric Rating Scale for Pain, Western Ontario and McMaster Universities Index (WOMAC) score, gait speed, and EuroQol-Five Dimensions-Five Levels questionnaire assessed at baseline, Week 3, and Week 6. Adverse events and patient satisfaction were evaluated at Week 3. RESULTS: At Week 3, the study group demonstrated statistical improvement compared to the control group for Numeric Rating Scale for Pain, WOMAC Total, WOMAC Pain, and WOMAC Stiffness. The mean difference (95% confidence interval) between groups was 0.76 (0.21-1.30), 0.49 (0.03-0.95), 0.63 (0.13-1.13), and 0.62 (0.04-1.20), respectively. However, the mean differences between groups were below the Minimally Clinically Important Difference values for each outcome. Additionally, there were no significant differences between groups at Week 6 for any outcome measure. CONCLUSION: IFC had no effect on pain reduction and functional improvement in patients with mild to moderate knee osteoarthritis.

7.
Environ Sci Technol ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258578

RESUMEN

High concentrations of microplastics (MPs) have been documented in the deep-sea surface sediments of the Arctic Ocean. However, studies investigating their high-resolution vertical distribution in sediments from the European waters to the Arctic remain limited. This study examines MPs in five sediment cores from the Norwegian Coastal Current (NCC), encompassing the water-sediment interface and sediment layers up to 19 cm depth. Advanced analytical methods for MP identification down to 11 µm in size were combined with radiometric dating and lithology observations. MPs were present across all sediment cores, including layers predating the introduction of plastics, with concentrations exhibiting significant variation (54-12,491 MP kg-1). The smallest size class (11 µm) predominated in most sediment layers (34-100%). A total of 18 different polymer types were identified across all sediment layers, with polymer diversity and depth correlations varying widely between stations. Our findings suggest that differences in seafloor topography and the impact of anthropogenic activities (e.g., fishing) lead to varying environmental conditions at the sampling sites, influencing the vertical distribution of MPs. This challenges the reliability of using environmental parameters to predict MP accumulation zones and questions the use of MPs in sediment cores as indicators of the Anthropocene.

8.
J Forensic Sci ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258748

RESUMEN

This study investigates the cardiac safety concerns related to TASER discharges centering on a pivotal case that marked the first TASER-related fatality in South Korea. Employing Pratt et al.'s theoretical framework, the research evaluates the potential for ventricular fibrillation (VF) from these discharges. The methodology incorporated a high-resolution waveform analysis using sophisticated equipment and considered specific incident details, including dart impact locations verified through a forensic examination. A human body impedance of 500 Ω, chosen based on empirical studies and coupled with non-inductive resistance for high-voltage handling, was utilized in the model. By applying a heart-current factor from IEC 60479 standards, the study found a VF risk of up to 5% depending on the impact location and current pathways. In this specific case, although the calculated risk did not exceed critical thresholds, the VF risk was high enough to suggest that TASER discharges played a role in the fatal outcome. This study underscores the importance of dart impact location in TASER safety evaluations, contributing to a broader understanding of TASER cardiac risks and providing a basis to advocate for rigorous safety protocols.

9.
Magn Reson Med ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39250435

RESUMEN

PURPOSE: To develop a 3D spherical EPTI (sEPTI) acquisition and a comprehensive reconstruction pipeline for rapid high-quality whole-brain submillimeter T 2 * $$ {\mathrm{T}}_2^{\ast } $$ and QSM quantification. METHODS: For the sEPTI acquisition, spherical k-space coverage is utilized with variable echo-spacing and maximum kx ramp-sampling to improve efficiency and signal incoherency compared to existing EPTI approaches. For reconstruction, an iterative rank-shrinking B0 estimation and odd-even high-order phase correction algorithms were incorporated into the reconstruction to better mitigate artifacts from field imperfections. A physics-informed unrolled network was utilized to boost the SNR, where 1-mm and 0.75-mm isotropic whole-brain imaging were performed in 45 and 90 s at 3 T, respectively. These protocols were validated through simulations, phantom, and in vivo experiments. Ten healthy subjects were recruited to provide sufficient data for the unrolled network. The entire pipeline was validated on additional five healthy subjects where different EPTI sampling approaches were compared. Two additional pediatric patients with epilepsy were recruited to demonstrate the generalizability of the unrolled reconstruction. RESULTS: sEPTI achieved 1.4 × $$ \times $$ faster imaging with improved image quality and quantitative map precision compared to existing EPTI approaches. The B0 update and the phase correction provide improved reconstruction performance with lower artifacts. The unrolled network boosted the SNR, achieving high-quality T 2 * $$ {\mathrm{T}}_2^{\ast } $$ and QSM quantification with single average data. High-quality reconstruction was also obtained in the pediatric patients using this network. CONCLUSION: sEPTI achieved whole-brain distortion-free multi-echo imaging and T 2 * $$ {\mathrm{T}}_2^{\ast } $$ and QSM quantification at 0.75 mm in 90 s which has the potential to be useful for wide clinical applications.

10.
Cerebrovasc Dis ; 53(3): 335-345, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39250901

RESUMEN

Research on the benefits of non-invasive brain stimulation in stroke patients to improve executive functions is scarce. The objective of this study was to investigate the effectiveness of transcranial direct current stimulation (tDCS) in combination with cognitive training for the rehabilitation of executive functions in acute and subacute stroke patients as well as to explore the underlying physiological mechanisms. A triple-blinded, randomized-controlled clinical trial will be conducted involving 60 stroke patients with frontal or basal ganglia lesions and a Montreal Cognitive Assessment (MoCA) score less than 26. Participants will be randomly assigned to receive active tDCS (anode over the left dorsolateral prefrontal cortex, cathode at the right supraorbital region, 20 min at 2 mA) or sham tDCS in a 1:1 ratio for 10 sessions, followed by targeted executive function training. The primary efficacy outcome will be the MoCA score, while secondary outcomes will include the five-digit test (inhibitory control), the Digit Span Task (working memory), the abbreviated version of the Wisconsin Card Sorting test (cognitive flexibility), modified Rankin scale (functional state), Beck-II depression inventory, apathy evaluation scale, and the WHOQOL-BREF (quality of life), assessed immediately after the intervention and at 1, 3, 6, and 12 months post-intervention. Additionally, resting-state functional connectivity and blood biomarkers, such as neurotrophins, growth factors, and inflammatory molecules, will be evaluated before and after the intervention. This study will contribute to the investigation of the efficacy of tDCS in rehabilitating executive functions in acute and subacute stroke patients. The multidimensional approach utilized in this study, which includes analysis of resting-state connectivity and neuroplasticity-related blood biomarkers, is expected to provide insights into the underlying brain mechanisms involved in the rehabilitation of dysexecutive syndrome.


Asunto(s)
Cognición , Función Ejecutiva , Ensayos Clínicos Controlados Aleatorios como Asunto , Recuperación de la Función , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Estimulación Transcraneal de Corriente Directa , Humanos , Masculino , Femenino , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/complicaciones , Persona de Mediana Edad , Resultado del Tratamiento , Anciano , Factores de Tiempo , Adulto , Terapia Cognitivo-Conductual , Terapia Combinada , Adulto Joven , Evaluación de la Discapacidad
11.
Data Brief ; 56: 110802, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39252770

RESUMEN

This paper introduces a meticulously organized dataset derived from the International Monetary Fund's World Economic Outlook (IMF WEO) forecasts, including GDP growth, CPI inflation, and current account balances for 196 countries from 1990 to 2024. Sourced from the WEO historical database and updated to 2024, the dataset contains forecasts of crucial economic indicators - GDP growth, CPI inflation, and current account balance - in an accessible and user-friendly Excel format. This dataset is a valuable resource for academic researchers, economists at central banks, finance ministries, and other stakeholders, enabling diverse analyses such as evaluations of IMF forecasts, research into optimism bias, and studies on equilibrium exchange rates. Additionally, it may be useful for foreign investors in making informed strategic investment decisions.

12.
J Affect Disord ; 367: 507-518, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39218314

RESUMEN

BACKGROUND: There is scarce data concerning the relationship between negative life events (NLEs)* and current and new depressive episodes by age. METHODS: Cross-sectional (baseline) and prospective analyses (4-year/8-year follow-ups) were performed in 15,105 civil servants in 6 cities in Brazil classified according to age strata at baseline: 1st(35-44), 2nd(45-54), 3rd(55-64), and 4th(65-74) years. The independent variable was NLEs in the last year (robbery, hospitalization, death of a relative, financial hardship, and rupture of a love relationship) collected at baseline. The dependent variable was depressive episodes assessed at baseline (current), and 4-year/8-year follow-ups (new). We built logistic (Odds Ratio[OR];95 % Confidence Interval[CI]) in the cross-sectional analysis and Poisson regression models (Relative Risk[RR], [CI]) in the prospective analysis. RESULTS: Robbery, hospitalization, financial hardship, rupture of a relationship were associated with current depressive episodes concentrated in the 35-44 age range, while for new depressive episodes, the association of hospitalization, death of a relative, and financial hardship were concentrated in the 45-54 age stratum. Financial hardship was associated with current depressive episodes in all age-strata: 1st: OR, 2.77(CI, 1.83-4.19); 2nd: OR, 1.71(CI, 1.26-2.34); 3rd: OR, 1.68(CI,1.15-2.46); 4th, OR, 4.07(CI, 1.24-13.34), and new depressive episodes: 1st: RR, 1.45(CI, 1.09-1.93); 2nd RR, 1.46(CI: 1.15-1.84); 3rd: RR, 1.97(CI, 1.38-2.82). Rupture of a relationship was associated only with current depressive episode, while death of a relative only with new depressive episode. LIMITATION: We cannot rule out the possibility of recall bias, since NLEs` information was self-reported. CONCLUSION: The association between NLEs with depressive episodes was concentrated in youngers.

13.
Int J Biol Macromol ; 279(Pt 2): 135312, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39236960

RESUMEN

Sensing motors and supercapacitors are pivotal in empowering smart systems, honing energy management, and facilitating the seamless integration of responsive electronics. Harnessing the electrochemistry of methylcellulose-polyaniline (MC/PANI) composites, this research delves into their potential applications as reactive current sensing supercapacitors with single connectivity. The electrochemical traits of pristine polyaniline (PANI) and MC/PANI composites were analyzed and assessed for their potential applications in sensors and energy storage devices. With a specific capacitance of 300Fg-1, the MC/PANI_B3 composite-based device retained 87.01 % capacitance after 2000 cycles. Besides, based on electrical energy as the sensing parameter, the composite exhibited augmented cathodic and anodic current sensitivity of 8.77 mJmA-1 and -8.86 mJmA-1, respectively. The ameliorated supercapacitor and current sensing parameters of MC/PANI_B3 are ascribed to the percolation threshold content of the conducting phase, which is endowed with optimal hydrogen bond-mediated interactions with methylcellulose (MC), thus confers an expanded chain conformation.

14.
Brain Lang ; 257: 105459, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39241469

RESUMEN

Transcranial direct current stimulation (tDCS) targeting Broca's area has shown promise for augmenting language production in post-stroke aphasia (PSA). However, previous research has been limited by small sample sizes and inconsistent outcomes. This study employed a double-blind, parallel, randomized, controlled design to evaluate the efficacy of anodal Broca's tDCS, paired with 20-minute speech and language therapy (SLT) focused primarily on expressive language, across 5 daily sessions in 45 chronic PSA patients. Utilizing the Western Aphasia Battery-Revised, which assesses a spectrum of linguistic abilities, we measured changes in both expressive and receptive language skills before and after intervention. The tDCS group demonstrated significant improvements over sham in aphasia quotient, auditory verbal comprehension, and spontaneous speech. Notably, tDCS improved both expressive and receptive domains, whereas sham only benefited expression. These results underscore the broader linguistic benefits of Broca's area stimulation and support the integration of tDCS with SLT to advance aphasia rehabilitation.

15.
Angew Chem Int Ed Engl ; : e202414493, 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39245630

RESUMEN

The adhesion of H2 bubbles on the electrode surface is one of the main factors limiting the performance of H2 evolution of electrolytic water, especially at high current density. To overcome this problem, here a "quasi-gas phase" electrolytic water reaction system based on capillary effect is proposed for the first time to improve the mass transfer efficiency of H2. The typical feature of this reaction system is that the main site of H2 evolution reaction is transferred from the bulk aqueous solution to the gas phase environment above the bulk aqueous solution, thus effectively inhibiting the aggregation of H2 bubbles and reducing the resistance of their diffusion away. Electrochemical test results show that the proposed quasi-gas phase system can significantly reduce the potential required in H2 evolution reaction process at high current density compared with the conventional electrolytic reaction system. Specifically, the overpotential potential is reduced by 0.31 V when the H2 evolution current density of 250 mA cm-2 is achieved.

16.
Adv Mater ; : e2406608, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39246123

RESUMEN

Smart memristors with innovative properties are crucial for the advancement of next-generation information storage and bioinspired neuromorphic computing. However, the presence of significant sneak currents in large-scale memristor arrays results in operational errors and heat accumulation, hindering their practical utility. This study successfully synthesizes a quasi-free-standing Bi2O2Se single-crystalline film and achieves layer-controlled oxidation by developing large-scale UV-assisted intercalative oxidation, resulting ß-Bi2SeO5/Bi2O2Se heterostructures. The resulting ß-Bi2SeO5/Bi2O2Se memristor demonstrates remarkable self-rectifying resistive switching performance (over 105 for ON/OFF and rectification ratios, as well as nonlinearity) in both nanoscale (through conductive atomic force microscopy) and microscale (through memristor array) regimes. Furthermore, the potential for scalable production of self-rectifying ß-Bi2SeO5/Bi2O2Se memristor, achieving sub-pA sneak currents to minimize cross-talk effects in high-density memristor arrays is demonstrated. The memristors also exhibit ultrafast resistive switching (sub-100 ns) and low power consumption (1.2 pJ) as characterized by pulse-mode testing. The findings suggest a synergetic effect of interfacial Schottky barriers and oxygen vacancy migration as the self-rectifying switching mechanism, elucidated through controllable ß-Bi2SeO5 thickness modulation and theoretical ab initio calculations.

17.
Small ; : e2402500, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39246184

RESUMEN

In order to enhance the overall efficiency of colloidal quantum dots solar cells, it is crucial to suppress the recombination of charge carriers and minimize energy loss at the interfaces between the transparent electrode, electron transport layer (ETL), and colloidal quantum dots (CQDs) light-absorbing material. In the current study, ZnO/SrTiO3 (STO), ZnO/WO3 (TO), and ZnO/Zn2SnO4 (ZTO) bilayers are introduced as an ETL using a spin-coating technique. The ZTO interlayer exhibits a smoother surface with a root-mean-square (RMS) value of ≈ 3.28 nm compared to STO and TO interlayers, which enables it to cover the surface of the ITO/ZnO substrate entirely and helps to prevent direct contact between the CQDs absorber layer and the ITO/ZnO substrate, thereby effectively preventing efficient charge recombination at the interfaces of the ETL/CQDs. Furthermore, the ZTO interlayer possesses superior electron mobility, a higher visible light transmission, and a suitable energy band structure compared to STO and TO. These characteristics are advantageous for extracting charge carriers and facilitating electron transport. The PbS CQDs solar cell based on the ITO/ZnO/ZTO/PbS-FABr/PbS-EDT/NiO/Au device configuration exhibits the highest efficiency of 15.28%, which is significantly superior than the ITO/ZnO/PbS-FABr/PbS-EDT/NiO/Au solar cell device (PCE = 14.38%). This study is anticipated to offer a practical approach to develop ultrathin and compact ETL for highly efficient CQDSCs.

18.
Small Methods ; : e2400264, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248649

RESUMEN

Cation deficiency tuning is a central issue in thin-film epitaxy of functional metal oxides, as it is typically more difficult than anion deficiency tuning, as anions can be readily supplied from gas sources. Here, highly effective internal deficiency compensation of Ru cations is demonstrated for Ca2RuO4 epitaxial films based on diffusive transfer of metal cations in the A2BO4 Ruddlesden-Popper lattice from solid-phase cation sources. Through detailed structural characterization of Ca2RuO4/LaAlO3 (001) thin films grown with external cation sources by solid-phase epitaxy, the occurrence of intercalation-like, interstitial diffusion of La cations (from the substrates) in the A2BO4 structure is revealed, and that of Ru cations is also suggested. Relying on the interstitial-type diffusion, an optimized Ru deficiency compensation method, which does not induce the formation of Can +1RunO3 n +1 Ruddlesden-Popper impurity phases with higher n, is proposed for Ca2RuO4 epitaxial films. In the Ca2RuO4/LaAlO3 (001) thin films grown with Ru deficiency compensation, record-high resistivity values (102-10-1 Ω cm) and a large (more than 200 K) increase in the temperature range of the nonlinear transport properties are demonstrated by transport measurements, demonstrating the possible advantages of this method in the control of the current-induced quantum phase transition of Ca2RuO4.

19.
Small ; : e2404835, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248690

RESUMEN

Lithium (Li) metal is regarded as the most promising anode for next-generation batteries with high energy density. However, the uncontrolled dendrite growth and infinite volume expansion during cycling seriously hinder the application of Li metal batteries (LMBs). Herein, an inorganic/organic protective layer (labeled as BPH), composed of in situ formed inorganic constituents and PVDF-HFP, is designed on the 3D carbon paper (CP) surface by hot-dipping method. The BPH layer can effectively improve the mechanical strength and ionic conductivity of the SEI layer, which is beneficial to expedite the Li-ion transfer of the entire framework and achieve stable Li plating/stripping behavior. As a result, the modified 3D CP (BPH-CP) exhibits an ultrahigh average Coulombic efficiency (CE) of ≈99.7% over 400 cycles. Further, the Li||LiFePO4 (LFP) cell exhibits an extremely long-term cycle life of over 3000 cycles at 5 C. Importantly, the full cell with high mass loading LiFePO4 (20 mg cm-2) or LiNi0.8Co0.1Mn0.1O2 (NCM, 16 mg cm-2) cathode exhibits stable cycling for 100 or 150 cycles at 0.5 C with high-capacity retention of 86.5% or 82.0% even at extremely low N/P ratio of 0.88 or 0.94. believe that this work enlightens a simple and effective strategy for the application of high-energy-density and high-rate-C LMBs.

20.
Sci Prog ; 107(3): 368504241275372, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39223921

RESUMEN

This study introduces an approach for converting the current from a sensor into controllable voltage. To this end, a switched-capacitor structure was integrated to provide efficient current-to-voltage conversion. The generated voltage was further regulated by an operational amplifier current source, enhancing stability and precision. An n-type metal oxide semiconductor field-effect transistor structure under an H-bridge was integrated into the system to achieve fine-tuned control over current stimulation. This component contributed to voltage regulation and enabled bi-directional control of current flow, offering versatility in adjusting current amplitudes using working and counter electrodes. This dynamic control mechanism was pivotal for effectively controlling the intensity of current stimulation. We applied Verilog-A modeling to simulate the optical characteristics of Si nanowires. The proposed system efficiently converted sensor-derived current into voltage using a switched-capacitor structure. Simultaneously, the precision was enhanced via operational amplifier regulation and n-type metal-oxide-semiconductor field-effect transistor-based H-bridge control. The simulation showed a current stimulus amplitude ranging from 2 to 13 µA for a variable photocurrent of Si nanowires (Rex: 10 kΩ, pulse: 100 Hz, 1 ms). The ability to finely control current stimulation intensity holds promise for diverse applications requiring accurate and adjustable current manipulation. This study contributes to the growing field of sensor technology by offering a unique perspective on the integration of nanostructures and electronic components for an enhanced control and functionality.

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