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1.
Sci Rep ; 14(1): 19529, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39174644

RESUMEN

This study investigated the statistical properties of solar wind parameters spanning Solar Cycles 20-24, elucidating periodicities that closely aligned with the solar cycle. Significantly, correlations between the smoothed 27-day average value of solar wind parameters and sunspot numbers (SSN) were discerned, shedding light on the intricate interplay between solar activity and solar wind characteristics. Furthermore, the study employed an optimized Long Short-Term Memory (LSTM+) model for forecasting Solar Cycle 25, demonstrating promising predictive capabilities. The analysis predicted the occurrence time of the peak value of SSN in Solar Cycle 25 to be on 27 October 2024 ± 136 days, based on the average relationship with the occurrence time of the trough of Plasma Beta. Notably, observations revealed a double peak in SC-25's solar activity, introducing uncertainty regarding the relative magnitude of each peak.

2.
ACS Appl Mater Interfaces ; 16(15): 19838-19848, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38569046

RESUMEN

Environment-friendly antisolvents are critical for obtaining highly efficient, reproducible, and sustainable perovskite solar cells (PSCs). Here, we introduced a green mixture antisolvent of ethyl acetate-isopropanol (EA/IPA) to finely regulate the crystal grain growth and related film properties, including the morphology, crystal structure, and chemical composition of the perovskite thin film. The IPA with suitable content in EA plays a key role in achieving a smooth and compact high-quality perovskite thin film, leading to the suppression of film defect-induced nonradiative recombination. As a result, the PSCs based on the EA/IPA (5:1) antisolvent showed a power conversion efficiency of 22.9% with an open-circuit voltage of 1.17 V.

3.
Heliyon ; 10(5): e26327, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38468935

RESUMEN

High performance flexible all-thin-film electrochromic devices (ATF-ECDs) have been fabricated and systematically investigated by operating with different driving voltages during the electrochromic processes. The device structure (cross-section) and material properties of some main functional layers were presented and analysed. The electrochromic properties including kinetic and spectral tests were systematically investigated through combining chronoamperometry, cyclic voltammetry measurements and optical measurements. In addition, the open circuit memory measurement was also carried out. A much higher driving voltage might lead to a current leakage inside the device during coloring process. A proper driving voltage is needed for achieving high device performances. More details were widely described and deeply discussed.

4.
Neuromodulation ; 27(2): 312-320, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37897473

RESUMEN

BACKGROUND: Synchronized intestinal electrical stimulation (SIES), in which intestinal electrical stimulation (IES) is delivered in synchronization with the intrinsic slow wave of small intestine, was previously reported to be more potent in accelerating small intestine transit than IES delivered at fixed frequency and phase. We hypothesized that SIES is more potent in suppressing postprandial blood glucose by enhancing the release of glucagon-like peptide-1 (GLP-1) and insulin. MATERIALS AND METHODS: Rats underwent long-term implant of two pairs of electrodes at the duodenum for IES and SIES, respectively. Acute hyperglycemia was induced with glucagon, and the oral glucose tolerance test was performed on separate days with IES, SIES, or sham (no stimulation). RESULTS: 1. Glucagon reduced the percentage of normal slow wave in sham (70.9% ± 4.1%) from (84.9% ± 2.6%, p = 0.006) of control, which was ameliorated by SIES (82.5% ± 3.3%, p = 0.031). 2. IES and SIES reduced glucagon-induced increase of blood glucose (192 mg/dl) at 30 minutes by 17% and 20%, respectively. SIES showed a further inhibitory effect at 60 minutes (147 vs 171 mg/dl, p = 0.003, vs sham). 3. Compared with sham (139 pg/ml), GLP-1 at 30 minutes was increased in both IES (158 pg/ml) and SIES (169 pg/ml). GLP-1 level was still high at 60 minutes in rats with SIES. 4. At 30 minutes, the plasma insulin level was increased by 18.8 µIU/ml with SIES, which was significantly higher than that with sham (7.1 µIU/ml, p < 0.001) and IES (13.2 µIU/ml, p = 0.041). CONCLUSION: SIES is more effective than IES in reducing glucagon-induced acute hyperglycemia by enhancing the release of GLP-1 and insulin.


Asunto(s)
Glucagón , Hiperglucemia , Ratas , Animales , Glucemia , Hiperglucemia/inducido químicamente , Hiperglucemia/terapia , Péptido 1 Similar al Glucagón , Insulina , Estimulación Eléctrica
5.
Artículo en Inglés | MEDLINE | ID: mdl-37787059

RESUMEN

This paper proposes an optimized Long Short-Term Memory (LSTM+) model for predicting cumulative confirmed cases of COVID-19 in Germany, the UK, Italy, and Japan. The LSTM+ model incorporates two key optimizations: (1) fine-adjustment of parameters and (2) a 're-prediction' process that utilizes the latest prediction results from the previous iteration. The performance of the LSTM+ model is evaluated and compared with that of Backpropagation (BP) and traditional LSTM models. The results demonstrate that the LSTM+ model significantly outperforms both BP and LSTM models, achieving a Mean Absolute Percentage Error (MAPE) of less than 0.6%. Additionally, two illustrative examples employing the LSTM+ model further validate its general applicability and practical performance for predicting cumulative confirmed COVID-19 cases.

6.
Polymers (Basel) ; 15(20)2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37896423

RESUMEN

To investigate the influence of polypropylene-basalt hybrid fibers (PBHFCC) on the durability of ceramsite concrete, this study determined the appearance change, mass loss rate, relative dynamic elastic modulus, compressive strength and splitting tensile strength of ceramsite concrete with four kinds of hybrid fibers volume admixture under chloride erosion and dry-wet cycles. The results reveal that under this effect, the apparent damage of each group of specimens increased with the growth of the erosion time. The quality, compressive strength and splitting tensile strength of the specimens all increased gradually during the erosion age period of the first 72 d and gradually decreased after 72 d. The relative dynamic elastic modulus was similarly mutated in 48 d. When the hybrid fiber content of the specimens is 0.15 vol %, the enhancement effect of ceramsite concrete is better than that of the other three amounts. The relative dynamic elastic modulus value is used as a damage variable to establish the damage equation, and the damage evolution equation of PBHFCC considering the volume of hybrid fiber under chloride erosion and dry-wet cycle is derived. The conclusions can be used as a reference for the durability design and construction of PBHFCC.

7.
Med Biol Eng Comput ; 61(9): 2317-2327, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37060485

RESUMEN

Obesity is one of leading risk factors for type 2 diabetes and other types of chronic diseases. Synchronized intestinal electrical stimulation (SIES) has been explored for treating obesity and diabetes. In SIES, electrical stimulation is delivered to the small intestine in synchronization with the intrinsic intestinal myoelectrical activity (its basic rhythm is called slow wave) and therefore, the accurate detection of intestinal slow waves is critically important for SIES. The aim of this study is to detect the peaks in intestinal slow waves in real-time based on the automatic multiscale peak detection (AMPD) method. In this paper, we introduce an efficient technique for real-time detection of peaks in intestinal slow waves. The presented method is based on peak estimation of a given quasi-periodic signal using the AMPD method. This method uses a multi-scale approach to identify the peaks of the intestinal slow waves with high detection accuracy and a minimal delay. Throughout the experiments, the multi-scale technique is used to estimate the quasi-periodic signals using different signal-to-noise ratio, λ (optimal scale), and the "lag" ß (number of datapoints for right hand estimation) as important performance factors. The performance of the presented method is also calculated and utilized in the comparison process for 10 datasets of the intestinal slow waves from rats at λ = 150 ms and two values of ß = 100 ms and 150 ms. The experimental results show that the presented method has good overall accuracy for online peak detection while maintaining low memory and computational complexity. Numerically, the overall accuracy is above 90%, and 98% for the rodent intestinal slow waves at a time-lag of 150 ms. The developed SIES system has been applied to successfully reduce postprandial blood glucose in a rodent model of hyperglycemia. In conclusion, the developed algorithm is adequate for on-line peak detection of the intestinal slow waves; the SIES method used the developed peak detection algorithm which is effective in reducing postprandial blood glucose in a rodent model of hyperglycemia.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hiperglucemia , Ratas , Animales , Glucemia , Obesidad , Estimulación Eléctrica , Algoritmos
8.
Environ Monit Assess ; 195(3): 371, 2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36754889

RESUMEN

Dynamic assessment of the water environment reflects variations in water resources in a basin under the combined influence of nature and humans and is a prerequisite for rational water management. This study provides an integrated assessment of the water environment in a water quantity-quality-soil model. Using the long-term monthly data from hydrological monitoring stations, the water environment of the Yellow River basin is assessed from the year 2006 to 2019. The kernel density estimation and the Dagum Gini coefficient are used to analyze the spatial and temporal imbalances of the water environment. Geographic detectors are used to extract external driving factors of the unbalanced evolution. The study results reveal that (1) the water environment in the basin shows a fluctuating downward trend, which mainly depends on the organic pollution control indicators, with a contribution of 22.85%. Scores of the water environment in the midstream are lower than those in the upstream and downstream due to the heavy pollutant discharges. (2) The spatial imbalance shows a fluctuating downward trend. Inter-regional variation is the primary source of regional variation in the water environment, with an average contribution of 56.02%. (3) The temporal imbalance of the water environment is on the rise, with a degree of multipolarity. The significant left trailing feature of the kernel density curve suggests that there are areas within the basin where the water environment is extremely poor. (4) For the overall basin and upstream, economic development and technological innovation are the main external driving factors influencing the spatial and temporal imbalances of the water environment. For the midstream and downstream, population density and environmental regulations are the main drivers. The interaction of any two factors has a greater impact than the single one.


Asunto(s)
Monitoreo del Ambiente , Suelo , Humanos , Calidad del Agua , Agua , China
9.
Sci Rep ; 12(1): 6178, 2022 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-35418175

RESUMEN

It has been reported that the expression of CD44 variant 9 could be utilized as a predictive marker for the recurrence in early gastric cancer (EGC) after endoscopic submucosal dissection (ESD). And circFNDC3B was proved to increase the migration and invasion of gastric cancer (GC) cells. In this study, we recruited 96 EGC patients after ESD treatment and grouped them into High circFNDC3B expression group (High expression group) and Low circFNDC3B expression group (Low expression group). Accordingly, we found that the recurrence-free rate in the High expression group was lower than that in the Low expression group. In the High expression group, the relative expression of miR-942 and miR-510 was both suppressed while the relative expression of CDH1 mRNA and CD44 mRNA/protein was increased compared with those in the Low expression group. CircFNDC3B was found to target miR-942 and miR-510 and suppress their expressions respectively. Moreover, miR-942 was found to target CD44 mRNA while miR-510 was found to target CDH1 mRNA. The overexpression of circFNDC3B led to the down-regulation of miR-942 and miR-510, which accordingly resulted in the up-regulation of CD44 and CDH1 in MKN28 cells. Moreover, we found H. pylori infection could promote the expression of circFNDC3B, which also resulted in up-regulated CD44 and CDH1 mRNA level in rTip-α cultivated MKN28 cells. In summary, our study demonstrated that a higher level of circFNDC3B could lead to the increased expression of CD44 and CDH1 via modulating the signaling pathways of miR-942/CD44 and miR-510/CDH1 in EGC patients. And the up-regulation of CD44 and CDH1 would accordingly result in a higher recurrence rate of EGC patients treated by ESD.


Asunto(s)
Resección Endoscópica de la Mucosa , ARN Circular , Neoplasias Gástricas , Infecciones por Helicobacter , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/genética , ARN Mensajero/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/cirugía , Regulación hacia Arriba
10.
Adv Mater ; 32(52): e2005268, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33185295

RESUMEN

Kesterite-based Cu2 ZnSn(S,Se)4 semiconductors are emerging as promising materials for low-cost, environment-benign, and high-efficiency thin-film photovoltaics. However, the current state-of-the-art Cu2 ZnSn(S,Se)4 devices suffer from cation-disordering defects and defect clusters, which generally result in severe potential fluctuation, low minority carrier lifetime, and ultimately unsatisfactory performance. Herein, critical growth conditions are reported for obtaining high-quality Cu2 ZnSnSe4 absorber layers with the formation of detrimental intrinsic defects largely suppressed. By controlling the oxidation states of cations and modifying the local chemical composition, the local chemical environment is essentially modified during the synthesis of kesterite phase, thereby effectively suppressing detrimental intrinsic defects and activating desirable shallow acceptor Cu vacancies. Consequently, a confirmed 12.5% efficiency is demonstrated with a high VOC of 491 mV, which is the new record efficiency of pure-selenide Cu2 ZnSnSe4 cells with lowest VOC deficit in the kesterite family by Eg /q-Voc. These encouraging results demonstrate an essential route to overcome the long-standing challenge of defect control in kesterite semiconductors, which may also be generally applicable to other multinary compound semiconductors.

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