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1.
Nature ; 618(7963): 80-86, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36990110

RESUMEN

All-perovskite tandem solar cells provide high power conversion efficiency at a low cost1-4. Rapid efficiency improvement in small-area (<0.1 cm2) tandem solar cells has been primarily driven by advances in low-bandgap (approximately 1.25 eV) perovskite bottom subcells5-7. However, unsolved issues remain for wide-bandgap (> 1.75 eV) perovskite top subcells8, which at present have large voltage and fill factor losses, particularly for large-area (>1 cm2) tandem solar cells. Here we develop a self-assembled monolayer of (4-(7H-dibenzo[c,g]carbazol-7-yl)butyl)phosphonic acid as a hole-selective layer for wide-bandgap perovskite solar cells, which facilitates subsequent growth of high-quality wide-bandgap perovskite over a large area with suppressed interfacial non-radiative recombination, enabling efficient hole extraction. By integrating (4-(7H-dibenzo[c,g]carbazol-7-yl)butyl)phosphonic acid in devices, we demonstrate a high open-circuit voltage (VOC) of 1.31 V in a 1.77-eV perovskite solar cell, corresponding to a very low VOC deficit of 0.46 V (with respect to the bandgap). With these wide-bandgap perovskite subcells, we report 27.0% (26.4% certified stabilized) monolithic all-perovskite tandem solar cells with an aperture area of 1.044 cm2. The certified tandem cell shows an outstanding combination of a high VOC of 2.12 V and a fill factor of 82.6%. Our demonstration of the large-area tandem solar cells with high certified efficiency is a key step towards scaling up all-perovskite tandem photovoltaic technology.

2.
Nature ; 571(7764): 245-250, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31292555

RESUMEN

Solar cells based on metal halide perovskites are one of the most promising photovoltaic technologies1-4. Over the past few years, the long-term operational stability of such devices has been greatly improved by tuning the composition of the perovskites5-9, optimizing the interfaces within the device structures10-13, and using new encapsulation techniques14,15. However, further improvements are required in order to deliver a longer-lasting technology. Ion migration in the perovskite active layer-especially under illumination and heat-is arguably the most difficult aspect to mitigate16-18. Here we incorporate ionic liquids into the perovskite film and thence into positive-intrinsic-negative photovoltaic devices, increasing the device efficiency and markedly improving the long-term device stability. Specifically, we observe a degradation in performance of only around five per cent for the most stable encapsulated device under continuous simulated full-spectrum sunlight for more than 1,800 hours at 70 to 75 degrees Celsius, and estimate that the time required for the device to drop to eighty per cent of its peak performance is about 5,200 hours. Our demonstration of long-term operational, stable solar cells under intense conditions is a key step towards a reliable perovskite photovoltaic technology.

3.
J Am Chem Soc ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38838168

RESUMEN

Molecular self-assembly is a widely recognized approach for fabricating biomimetic functional nanostructures. Here, we report the synthesis of two giant hollow coronoid-like supramolecular hexagons, H1 and H2. These hexagons feature large cavities, showcasing unique inner and outer hexagons fixed by specific connectivities for enhanced stability and high metal center density. H1 exhibits properties that can be transformed through the thermodynamic conversion of the metallopolymer formed by L1 and L2. With an edge length of 6.8 nm, H2 is one of the largest hexagons reported to date. 1D and 2D NMR, TEM, ESI-MS, and TWIM-MS experiments provided conclusive evidence for the composition and structure of the assembled hexagons. This work demonstrates the feasibility of constructing giant supramolecular architectures with precise control over their size and shape, opening up new possibilities for the design and synthesis of sophisticated supramolecules and nonbiological materials.

4.
Radiology ; 307(3): e220996, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36880944

RESUMEN

Background Studies have rarely investigated stenosis detection from head and neck CT angiography scans because accurate interpretation is time consuming and labor intensive. Purpose To develop an automated convolutional neural network-based method for accurate stenosis detection and plaque classification in head and neck CT angiography images and compare its performance with that of radiologists. Materials and Methods A deep learning (DL) algorithm was constructed and trained with use of head and neck CT angiography images that were collected retrospectively from four tertiary hospitals between March 2020 and July 2021. CT scans were partitioned into training, validation, and independent test sets at a ratio of 7:2:1. An independent test set of CT angiography scans was collected prospectively between October 2021 and December 2021 in one of the four tertiary centers. Stenosis grade categories were as follows: mild stenosis (<50%), moderate stenosis (50%-69%), severe stenosis (70%-99%), and occlusion (100%). The stenosis diagnosis and plaque classification of the algorithm were compared with the ground truth of consensus by two radiologists (with more than 10 years of experience). The performance of the models was analyzed in terms of accuracy, sensitivity, specificity, and areas under the receiver operating characteristic curve. Results There were 3266 patients (mean age ± SD, 62 years ± 12; 2096 men) evaluated. The consistency between radiologists and the DL-assisted algorithm on plaque classification was 85.6% (320 of 374 cases [95% CI: 83.2, 88.6]) on a per-vessel basis. Moreover, the artificial intelligence model assisted in visual assessment, such as increasing confidence in the degree of stenosis. This reduced the time needed for diagnosis and report writing of radiologists from 28.8 minutes ± 5.6 to 12.4 minutes ± 2.0 (P < .001). Conclusion A deep learning algorithm for head and neck CT angiography interpretation accurately determined vessel stenosis and plaque classification and had equivalent diagnostic performance when compared with experienced radiologists. © RSNA, 2023 Supplemental material is available for this article.


Asunto(s)
Angiografía por Tomografía Computarizada , Aprendizaje Profundo , Masculino , Humanos , Inteligencia Artificial , Estudios Retrospectivos , Constricción Patológica
5.
Inorg Chem ; 62(23): 8923-8930, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37246851

RESUMEN

As a result of their optical and redox properties, bipyridyl (bpy) and terpyridyl (tpy) ruthenium complexes play vital roles in numerous domains. Herein, the design and synthesis of two bipyridyl and terpyridyl ruthenium(II) building units L1 and L2 are explained. A [Ru(bpy)3]2+ functionalized triangle S1 and a Sierpinski triangle S2 were synthesized in almost quantitative yields by the self-assembly of L1 with Zn2+ ions and by the heteroleptic self-assembly of L1 and L2 with Zn2+ ions, respectively. The Sierpinski triangle S2 contains the coordination metals [Ru(bpy)3]2+, [Ru(tpy)2]2+, and [Zn(tpy)2]2+. According to research on the catalytic activity of amine oxidation on supramolecules S1 and S2, the benzylamine substrates were nearly entirely transformed to N-benzylidenebenzylamine derivatives after 1 h under a Xe lamp. Furthermore, the observed ruthenium-containing terpyridyl supramolecule S2 maintains high luminous performance at ambient temperature. This discovery opens up new possibilities for the rational molecular design of terpyridyl ruthenium fluorescent materials and catalytic functional materials.

6.
BMC Pregnancy Childbirth ; 23(1): 840, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057742

RESUMEN

BACKGROUND: Prior studies have shown that, when administered as an intravenous bolus to prevent uterine atony, prophylactic phenylephrine infusion increased the dose requirement of oxytocin and second-line uterotonics. For the prevention of uterine atony, oxytocin should be delivered by continuous infusion. Here, we aimed to determine the ED50 and ED90 parameters (the effective doses for 50 and 90% patients without uterine atony) of oxytocin for co-infusion with prophylactic phenylephrine during cesarean delivery. METHODS: In this prospective randomized double-blinded dose-finding study, one hundred patients were divided into four groups to receive 2.5, 5.0, 7.5, or 10 IU/h oxytocin infusion, after the umbilical cord was clamped during the study period. The uterine tone was evaluated and defined as either adequate or inadequate. Probit regression analysis was applied to calculate the ED50 and ED90 of oxytocin infusion. Uterine tone, the percentage of patients who needed additional oxytocin bolus, second-line uterotonics, side effects, estimated blood loss, and neonatal outcomes were monitored. RESULTS: The estimated ED50 and ED90 values of the oxytocin infusion doses for the prevention of uterine atony were 1.9 IU/h (95% CI -4.6-3.8) IU/h and 9.3 IU/h (95% CI 7.3-16.2) IU/h, respectively. Across groups, there was a significant linear trend between the infusion dose and the percentage of patients who required additional oxytocin (p-value = 0.002). No differences were observed in the incidence of side effects and neonatal outcomes. CONCLUSION: Under the conditions of this study, the ED90 of oxytocin infusion for the prevention of uterine atony was 9.3 IU/h, which is higher than the current recommendation. This finding is helpful for clinical practice, because of the routine use of phenylephrine in cesarean delivery. Further studies are needed to determine the appropriate initial bolus of oxytocin after neonatal delivery. TRIAL REGISTRATION: The study was registered on the Chinese Clinical Trial Register (register no. ChiCTR2200059556 ).


Asunto(s)
Hipotensión , Oxitócicos , Inercia Uterina , Embarazo , Femenino , Recién Nacido , Humanos , Oxitocina , Fenilefrina , Estudios Prospectivos , Hipotensión/etiología , Hipotensión/prevención & control , Método Doble Ciego , Infusiones Intravenosas
7.
Angew Chem Int Ed Engl ; 62(1): e202214237, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36323638

RESUMEN

Fractal structures with self-similarity are of fundamental importance in the fields of aesthetic, chemistry and mathematics. Here, by taking advantage of constructs the rational geometry-directed precursor design, we report the construction of two fascinating Platonic solids, the Sierpinski tetrahedron ST-T and the Sierpinski octahedron ST-O, in which each possesses a fractal Sierpinski triangle on their independent faces. These two discrete complexes are formed in near-quantitative yield from the multi-component self-assembly of truncated Sierpinski triangular kernel L1 with tribenzotriquinacene-based hexatopic and anthracene-based tetratopic terpyridine ligands (L3 and L4 ) in the presence of metal ions, respectively. The enhanced stabilities of the 3D discrete structures were investigated by gradient tandem mass spectrometry (gMS2 ). This work provides new constructs for the imitation of complex virus assemblies and for the molecular encapsulation of giant guest molecules.


Asunto(s)
Espectrometría de Masas en Tándem , Ligandos
8.
J Cell Mol Med ; 25(2): 1128-1139, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33459528

RESUMEN

Interleukin 18 (IL-18) is a pleiotropic pro-inflammatory cytokine and is associated with arrested follicle development and anovulation which are the typical pathological changes of PCOS. Theca cells (TCs) have a key role in follicular growth and atresia. But whether IL-18 can directly affect ovarian TCs function is unknown. Therefore, the objective of this study was to determine the effect of IL-18 on proliferation and steroidogenesis of bovine TCs and to explore the biological effect of IL-18 on folliculogenesis. This work revealed that at 300-1000 pg/mL, IL-18 led to a time- and dose-dependently increase in cell proliferation (P < .05). IL-18 increased 17-hydroxyprogesterone (17OHP4) and androstenedione (A2) secretion with up-regulation of key steroidogenesis-related genes CYP11A1 and CYP17A1 (P < .05). Furthermore, our data demonstrated that the IL-18R protein is predominantly expressed in small-follicle (3-6 mm) TCs than large follicles (8-22 mm) by immunohistochemistry. We also found that the stimulation effects of IL-18 on TCs can be reversed with the addition of IL-18BP as early as at 4 hours of culture and reached the peak at 16 hours. We conclude that IL-18 appears to target TCs in bovine, and suggest an important role for this cytokine in ovarian function. Present findings further validate potential effects of IL-18 in the conditions associated with follicular dysplasia and excessive growth of ovarian TCs (such as PCOS). But additional research is needed to further understand the mechanism of action of IL-18 in theca cells as well as its precise role in folliculogenesis.


Asunto(s)
Interleucina-18/farmacología , Síndrome del Ovario Poliquístico/patología , Esteroides/biosíntesis , Células Tecales/metabolismo , Animales , Bovinos , Proliferación Celular/efectos de los fármacos , Separación Celular , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Hormona Luteinizante/farmacología , Síndrome del Ovario Poliquístico/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Interleucina-18/metabolismo
9.
Eur Radiol ; 31(4): 1863-1871, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32997181

RESUMEN

OBJECTIVES: To evaluate the utility of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in predicting the response of chemotherapy and clinical outcomes in primary central-nervous-system lymphoma (PCNSL) patients. METHODS: DCE-MRI in 56 patients enrolled in a prospective study was performed at baseline and 30 days after treatment from 2016 to 2019. Multivariate logistic regression analyses were performed to assess risk factors for tumor responses. The predictive values of related parameters derived from DCE were analyzed via receiver operating characteristic (ROC) curve analysis. To evaluate prognostic factors, the Kaplan-Meier survival analysis with log-rank tests and Cox regression tests were analyzed. RESULTS: Ktrans and Ve were higher in the non-response group than in the response group (p < 0.05). The Ktrans and the percentage of Ktrans decreased after 30 days of treatment were independent predictors of chemotherapy responses (p = 0.034 and p = 0.019). ROC analysis indicated that the cut-off point of Ktrans for predicting chemotherapeutic responses was 0.353 min-1 (AUC, 0.941; 95% CI, 0.87-1; p < 0.001) and percentage of Ktrans decreased after 30 days of treatment was 15.2% (AUC, 0.858; 95% CI, 0.742-0.970; p < 0.001). The greater decrease in Ktrans correlated with a longer progression-free survival (PFS) (χ2 = 13.203, p < 0.001). The higher Ktrans was an independent predictor for shorter PFS (hazard ratio, 10.182; 95% CI, 2.510-41.300; p = 0.001). CONCLUSIONS: Ktrans and Ktrans change measured by DCE-MRI were reliable biomarkers for predicting chemotherapy responses in PCNSL patients. KEY POINTS: • Baseline Ktrans and greater decrease in Ktrans can predict chemotherapeutic efficacy. • DCE-MRI provides quantitative parameters reflecting the tumor microenvironment. • Targeted treatment therapy can be given with more evidence in the future.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Medios de Contraste , Biomarcadores , Humanos , Imagen por Resonancia Magnética , Estudios Prospectivos , Microambiente Tumoral
10.
Br J Sociol ; 72(3): 543-565, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33970490

RESUMEN

Various "rich lists" indicate that China now has one of the highest percentages of super rich people worldwide. However, very little is known about their sociopolitical profiles. Based on the annual Hurun China Rich Lists from 2000 to 2018, we created a new dataset of China's super rich that combines information from various sources. Using a multiple correspondent analysis, we reveal that the social spaces of China's super rich are derived from their political, cultural, and social capital. The Chinese super rich are mainly distinguished by their cultural and political capital, while their social capital is not fully independent from political capital. We also identify a division among the super-rich who first appeared on the rich list during different periods. These divisions can inform the understanding of the emergence of the super-rich in an economy that has only recently embraced capitalism and can help predict their evolution in an increasingly glocalized system.


Asunto(s)
Capitalismo , Capital Social , China , Humanos
11.
Acta Radiol ; 60(3): 367-373, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29871494

RESUMEN

BACKGROUND: Positive "dynamic spot sign" has been proven to be a potential risk factor for acute intracerebral hemorrhage (ICH) expansion, but local perfusion change has not been quantitatively investigated. PURPOSE: To quantitatively evaluate perfusion changes at the ICH area using computed tomography perfusion (CTP) imaging. MATERIAL AND METHODS: Fifty-three patients with spontaneous ICH were recruited. Unenhanced computed tomography (NCCT), CTP within 6 h, and follow-up NCCT were performed for 21 patients in the "spot sign"-positive group and 32 patients in the control group. Cerebral perfusion change was quantitatively measured on regional cerebral blood flow/regional cerebral blood volume (rCBF/rCBV) maps. Regions of interest (ROIs) were set at the "spot-sign" region and the whole hematoma area for "spot-sign"-positive cases, and at one of the highest values of three interested areas and the whole hematoma area for the control group. Hematoma expansion was determined by follow-up NCCT. RESULTS: For the "spot-sign"-positive group, the average rCBF (rCBV) values at the "spot-sign" region and the whole hematoma area were 21.34 ± 15.24 mL/min/100 g (21.64 ± 21.48 mL/100g) and 5.78 ± 6.32 mL/min/100 g (6.07 ± 5.45 mL/100g); for the control group, the average rCBF (rCBV) values at the interested area and whole hematoma area were 2.50 ± 1.83 mL/min/100 g (3.13 ± 1.96 mL/100g) and 3.02 ± 1.80 mL/min/100 g (3.40 ± 1.44 mL/100g), respectively. Average rCBF and rCBV values of the "spot-sign" region were significantly different from other regions ( P < 0.001; P = 0.004). The average volumes of hematoma expansion in the "spot-sign"-positive and control groups were 25.24 ± 19.38 mL and -0.41 ± 1.34 mL, respectively. CONCLUSION: The higher perfusion change at ICH on CTP images may reflect the contrast extravasation and be associated with the hematoma expansion.


Asunto(s)
Hemorragia Cerebral/diagnóstico por imagen , Circulación Cerebrovascular , Tomografía Computarizada por Rayos X/métodos , Adulto , Algoritmos , Volumen Sanguíneo , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Factores de Riesgo
12.
Stroke ; 49(9): 2074-2080, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30354984

RESUMEN

Background and Purpose- The aim of the study was to investigate the utility of iodine contrast agent leakage (the iodine sign) analyzed by Gemstone spectral imaging in early hematoma formation compared with that of the spot sign for predicting early hematoma expansion (HE) and poor functional outcomes. Methods- From 2014 to 2017, 91 patients with spontaneous intracerebral hemorrhage who underwent spectral computed tomography angiography within 6 hours of spontaneous intracerebral hemorrhage onset were prospectively included in our study. We defined a positive iodine sign as tiny enhancing foci within the hematoma on Gemstone spectral imaging and an iodine concentration inside the foci of >7.82 (100 µg/mL). Univariate and multivariate logistical regression analyses were performed to assess risk factors for HE, and the predictive value of HE was analyzed. Results- Positive spot and iodine signs were present in 38.5% (35/91) and 57.1% (52/91) of the patients, respectively. Using multivariate analysis, the iodine sign independently predicted HE (odds ratio, 53.67; 95% CI, 11.88-242.42; P<0.001) and had a higher sensitivity (91.5% versus 63.8%), negative predictive value (89.7% versus 69.9%), and accuracy (85.7% versus 75.8%) for detecting HE than the spot sign. The iodine sign, but not the spot sign, was significantly related to poor functional outcomes (severely disabled and vegetative state) in all patients (χ2=29.97; P<0.001). Conclusions- The iodine sign is a reliable and sensitive marker for predicting HE and poor functional outcomes. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02625948.


Asunto(s)
Encéfalo/diagnóstico por imagen , Hemorragia Cerebral/diagnóstico por imagen , Medios de Contraste , Hematoma/diagnóstico por imagen , Compuestos de Yodo , Adulto , Anciano , Angiografía Cerebral/métodos , Hemorragia Cerebral/fisiopatología , Estudios de Cohortes , Angiografía por Tomografía Computarizada/métodos , Progresión de la Enfermedad , Femenino , Hematoma/fisiopatología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico
13.
Eur Radiol ; 28(10): 4343-4349, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29675658

RESUMEN

OBJECTIVES: The computed tomography angiography (CTA) spot sign is a validated predictor of haematoma expansion (HE) in spontaneous intracerebral haemorrhage (SICH). We investigated whether defining the iodine concentration (IC) inside the spot sign and the haematoma on Gemstone spectral imaging (GSI) would improve its sensitivity and specificity for predicting HE. METHODS: From 2014 to 2016, we prospectively enrolled 65 SICH patients who underwent single-phase spectral CTA within 6 h. Logistic regression was performed to assess the risk factors for HE. The predictive performance of individual spot sign characteristics was examined via receiver operating characteristic (ROC) analysis. RESULTS: The spot sign was detected in 46.1% (30/65) of patients. ROC analysis indicated that IC inside the spot sign had the greatest area under the ROC curve for HE (0.858; 95% confidence interval, 0.727-0.989; p = 0.003). Multivariate analysis found that spot sign with higher IC (i.e. IC > 7.82 100 µg/ml) was an independent predictor of HE (odds ratio = 34.27; 95% confidence interval, 5.608-209.41; p < 0.001) with sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 0.81, 0.75, 0.90 and 0.60, respectively; while the spot sign showed sensitivity, specificity, PPV and NPV of 0.81, 0.79, 0.73 and 0.86. Logistic regression analysis indicated that the IC in haematomas was independently associated with HE (odds ratio = 1.525; 95% confidence interval, 1.041-2.235; p = 0.030). CONCLUSIONS: ICs in haematoma and in spot sign were all independently associated with HE. IC analysis in spectral imaging may help to identify SICH patients for targeted haemostatic therapy. KEY POINTS: • Iodine concentration in spot sign and haematoma can predict haematoma expansion • Spectral imaging could measure the IC inside the spot sign and haematoma • IC in spot sign improved the positive predictive value (PPV) cf. CTA.


Asunto(s)
Hemorragia Cerebral/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Medios de Contraste , Extravasación de Materiales Terapéuticos y Diagnósticos , Hematoma/diagnóstico por imagen , Yohexol , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Curva ROC , Factores de Riesgo , Sensibilidad y Especificidad
14.
Sci Technol Adv Mater ; 19(1): 871-882, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30479675

RESUMEN

Structural defects such as voids and compositional inhomogeneities may affect the performance of Cu(In,Ga)Se2 (CIGS) solar cells. We analyzed the morphology and elemental distributions in co-evaporated CIGS thin films at the different stages of the CIGS growth by energy-dispersive x-ray spectroscopy in a transmission electron microscope. Accumulation of Cu-Se phases was found at crevices and at grain boundaries after the Cu-rich intermediate stage of the CIGS deposition sequence. It was found, that voids are caused by Cu out-diffusion from crevices and GBs during the final deposition stage. The Cu inhomogeneities lead to non-uniform diffusivities of In and Ga, resulting in lateral inhomogeneities of the In and Ga distribution. Two and three-dimensional simulations were used to investigate the impact of the inhomogeneities and voids on the solar cell performance. A significant impact of voids was found, indicating that the unpassivated voids reduce the open-circuit voltage and fill factor due to the introduction of free surfaces with high recombination velocities close to the CIGS/CdS junction. We thus suggest that voids, and possibly inhomogeneities, limit the efficiency of solar cells based on three-stage co-evaporated CIGS thin films. Passivation of the voids' internal surface may reduce their detrimental effects.

15.
Bioengineering (Basel) ; 11(3)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38534567

RESUMEN

The 12-lead electrocardiogram (ECG) is crucial in assessing patient decisions. However, portable ECG devices capable of acquiring a complete 12-lead ECG are scarce. For the first time, a deep learning-based method is proposed to reconstruct the 12-lead ECG from Frank leads (VX, VY, and VZ) or EASI leads (VES, VAS, and VAI). The innovative ECG reconstruction network called M2Eformer is composed of a 2D-ECGblock and a ProbDecoder module. The 2D-ECGblock module adaptively segments EASI leads into multi-periods based on frequency energy, transforming the 1D time series into a 2D tensor representing within-cycle and between-cycle variations. The ProbDecoder module aims to extract Probsparse self-attention and achieve one-step output for the target leads. Experimental results from comparing recorded and reconstructed 12-lead ECG using Frank leads indicate that M2Eformer outperforms traditional ECG reconstruction methods on a public database. In this study, a self-constructed database (10 healthy individuals + 15 patients) was utilized for the clinical diagnostic validation of ECG reconstructed from EASI leads. Subsequently, both the ECG reconstructed using EASI and the recorded 12-lead ECG were subjected to a double-blind diagnostic experiment conducted by three cardiologists. The overall diagnostic consensus among three cardiology experts, reaching a rate of 96%, indicates the significant utility of EASI-reconstructed 12-lead ECG in facilitating the diagnosis of cardiac conditions.

16.
Adv Mater ; 36(28): e2401359, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38663867

RESUMEN

With the continuous upsurge in demand for wearable energy, nanogenerators are increasingly required to operate under extreme environmental conditions. Even though they are at the cutting edge of technology, nanogenerators have difficulty producing high-quality electrical output at very extreme temperatures. Here, a triboelectric basalt textile (TBT) with an ultrawide operational temperature range (from -196 to 520 °C) is created employing basalt material as the main body. The output power density of the TBT, in contrast to most conventional nanogenerators, would counterintuitively rise by 2.3 times to 740.6 mW m-2 after heating to 100 °C because the high temperature will enhance the material's interface polarization and electronic kinetic energy. The TBT retains ≈55% of its initial electrical output even after heating in the flame of an alcohol lamp (520 °C). Surprisingly, the TBTs output voltage may retain over 85% of its initial value even after submerging in liquid nitrogen. The TBTs exceptional resistance to heat and cold indicates its possible use in high and low latitudes, high altitudes, deserts, and even space settings.

17.
Front Bioeng Biotechnol ; 12: 1403511, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919382

RESUMEN

Gliomas are typical malignant brain tumours affecting a wide population worldwide. Operation, as the common treatment for gliomas, is always accompanied by postoperative drug chemotherapy, but cannot cure patients. The main challenges are chemotherapeutic drugs have low blood-brain barrier passage rate and a lot of serious adverse effects, meanwhile, they have difficulty targeting glioma issues. Nowadays, the emergence of nanoparticles (NPs) drug delivery systems (NDDS) has provided a new promising approach for the treatment of gliomas owing to their excellent biodegradability, high stability, good biocompatibility, low toxicity, and minimal adverse effects. Herein, we reviewed the types and delivery mechanisms of NPs currently used in gliomas, including passive and active brain targeting drug delivery. In particular, we primarily focused on various hopeful types of NPs (such as liposome, chitosan, ferritin, graphene oxide, silica nanoparticle, nanogel, neutrophil, and adeno-associated virus), and discussed their advantages, disadvantages, and progress in preclinical trials. Moreover, we outlined the clinical trials of NPs applied in gliomas. According to this review, we provide an outlook of the prospects of NDDS for treating gliomas and summarise some methods that can enhance the targeting specificity and safety of NPs, like surface modification and conjugating ligands and peptides. Although there are still some limitations of these NPs, NDDS will offer the potential for curing glioma patients.

18.
Front Neurol ; 15: 1413582, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974685

RESUMEN

Background: Epilepsy ranks among the most common neurological disorders worldwide, frequently accompanied by depression as a prominent comorbidity. This study employs bibliometric analysis to reveal the research of comorbid epilepsy and depression over the past two decades, aiming to explore trends and contribute insights to ongoing investigations. Methods: We conducted a comprehensive search on the Web of Science Core Collection database and downloaded relevant publications on comorbid epilepsy and depression published from 2003 to 2023. VOSviewer and CiteSpace were mainly used to analyze the authors, institutions, countries, publishing journals, reference co-citation patterns, keyword co-occurrence, keyword clustering, and other aspects to construct a knowledge atlas. Results: A total of 5,586 publications related to comorbid epilepsy and depression were retrieved, with a general upward trend despite slight fluctuations in annual publications. Publications originated from 121 countries and 636 institutions, with a predominant focus on clinical research. The United States led in productivity (1,529 articles), while Melbourne University emerged as the most productive institution (135 articles). EPILEPSY & BEHAVIOR was the journal with the highest publication output (1,189 articles) and citation count. Keyword analysis highlighted emerging trends, including "recognitive impairment" and "mental health," indicating potential future research hotspots and trends. Conclusion: This study is one of the first to perform a bibliometric analysis of the 20-year scientific output of comorbid epilepsy and depression. While research has trended upwards, ambiguity in pathogenesis and the absence of standardized diagnostic guidelines remain concerning. Our analysis offers valuable guidance for researchers, informing that this might be a strong area for future collaborations.

19.
Artículo en Inglés | MEDLINE | ID: mdl-39031069

RESUMEN

High-efficiency Pb-Sn narrow-bandgap perovskite solar cells (PSCs) heavily rely on PEDOT:PSS as the hole-transport layer (HTL) owing to its excellent electrical conductivity, dopant-free nature, and facile solution processability. However, the shallow work function (WF) of PEDOT:PSS consequently results in severe minority carrier recombination at the perovskite/HTL interface. Here, we tackle this issue by an in situ interface engineering strategy using a new molecule called 2-fluoro benzylammonium iodide (FBI) that suppresses nonradiative recombination near the Pb-Sn perovskite (FA0.6MA0.4Pb0.4Sn0.6I3)/HTL bottom interface. The WF of PEDOT:PSS increases by 0.1 eV with FBI modification, resulting in Pb-Sn PSCs with 20.5% efficiency and an impressive VOC of 0.843 V. Finally, we have successfully transferred our in situ buried interface modification strategy to fabricate blade-coated FA0.6MA0.4Pb0.4Sn0.6I3 PSCs with 18.3% efficiency and an exceptionally high VOC of 0.845 V.

20.
Nat Energy ; 9(2): 172-183, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38419691

RESUMEN

The stabilization of grain boundaries and surfaces of the perovskite layer is critical to extend the durability of perovskite solar cells. Here we introduced a sulfonium-based molecule, dimethylphenethylsulfonium iodide (DMPESI), for the post-deposition treatment of formamidinium lead iodide perovskite films. The treated films show improved stability upon light soaking and remains in the black α phase after two years ageing under ambient condition without encapsulation. The DMPESI-treated perovskite solar cells show less than 1% performance loss after more than 4,500 h at maximum power point tracking, yielding a theoretical T80 of over nine years under continuous 1-sun illumination. The solar cells also display less than 5% power conversion efficiency drops under various ageing conditions, including 100 thermal cycles between 25 °C and 85 °C and an 1,050-h damp heat test.

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