GaN/GaInN asymmetric multiple quantum well light-emitting diodes with varying potential barrier thicknesses (5 and 15 nm) are grown by using metal organic chemical vapor deposition. The narrow ...barrier structure improves the performance of the device, including the super-linear increase of electroluminescence integral intensity, the mitigation of efficiency droop at high current density, the reduction of wavelength drift, the reduction of forward voltage, and the improvement of wall-plug efficiency. This is due to the narrowing of the thickness of the quantum barrier, which results in the smaller electric field among the quantum well, the weakening of the quantum confinement Stark effect, the more uniform distribution of carriers across the active region of the device, and the suppression of electron leakage.
A long-standing problem at the frontier of biomechanical studies is to develop fast methods capable of estimating material properties from clinical data. In this paper, we have studied three ...surrogate models based on machine learning (ML) methods for fast parameter estimation of left ventricular (LV) myocardium. We use three ML methods named K-nearest neighbour (KNN), XGBoost and multi-layer perceptron (MLP) to emulate the relationships between pressure and volume strains during the diastolic filling. Firstly, to train the surrogate models, a forward finite-element simulator of LV diastolic filling is used. Then the training data are projected in a low-dimensional parametrized space. Next, three ML models are trained to learn the relationships of pressure-volume and pressure-strain. Finally, an inverse parameter estimation problem is formulated by using those trained surrogate models. Our results show that the three ML models can learn the relationships of pressure-volume and pressure-strain very well, and the parameter inference using the surrogate models can be carried out in minutes. Estimated parameters from both the XGBoost and MLP models have much less uncertainties compared with the KNN model. Our results further suggest that the XGBoost model is better for predicting the LV diastolic dynamics and estimating passive parameters than other two surrogate models. Further studies are warranted to investigate how XGBoost can be used for emulating cardiac pump function in a multi-physics and multi-scale framework.
Three isoreticular hydrogen‐bonded frameworks with functionalized pore structures were constructed by a modular self‐assembly process in which a series of amino acids with various substituents serve ...as facile exchange subassemblies to decorate the pore wall. The ordered amino acid side‐chain groups in the pore channels play an important role in determining the adsorption behavior of the framework materials, and ensure exclusive adsorption of methanol/water over ethanol. Gas‐chromatographic separation experiments demonstrated that alcohols can be efficiently separated from ternary water/methanol/ethanol mixtures and revealed a key influence of the adsorbate–host framework interaction on the practical separation performance of mixtures.
Isoreticular H‐bonded frameworks with functionalized pore structures were constructed by modular self‐assembly. The ordered amino acid side‐chain groups in the pore channels play a crucial role in determining the adsorption behavior of the framework materials and ensure the efficient separation of ternary water/methanol/ethanol mixtures (see figure).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Crystalline materials with large tailor-made channels have been made by an isoreticular synthesis strategy, which includes a successful adjustment of the pi -conjugation over a framework skeleton ...allowing target recognition for aromatic molecules. The selective absorption of benzene over cyclohexane has been achieved, with a significant increase in benzene uptake with the improvement of the degree of pi -conjugation.
Far-field detection has been widely used in biomedical diagnosis, security inspection, such as MRI, ultrasonic, SPECT, X-ray, etc. However, the near-field detection has yet to be well established. ...This paper proposed a sensor structure with series inductance and capacitor. The inductance is a differential-transformer-type inductor formed by winding two spiral inductors. The interdigital capacitor is redesigned and placed inside the inductor to reduce its overall size. With the presence of the digital capacitor, the resonance shifts to the lower frequency, and the amplitude of return loss is increased. The micro-fabricated resonator was realized through integrated passive device technology for sensitive detection and characterization of glucose. The experimental results verified the performance of the proposed biosensor as the radio frequency multi-parameter bio-detector, such as the resonance frequency and the reflection coefficient. The detection results vary in response to deionized water, following by the iterative measurements of the changing glucose concentrations (from 50 to 150 mg<inline-formula> <tex-math notation="LaTeX">\cdot </tex-math></inline-formula>dL<inline-formula> <tex-math notation="LaTeX">^{-1} </tex-math></inline-formula>). The concentration of glucose solution changes from 50 mg<inline-formula> <tex-math notation="LaTeX">\cdot </tex-math></inline-formula>dL<inline-formula> <tex-math notation="LaTeX">^{-1} </tex-math></inline-formula> to 150 mg<inline-formula> <tex-math notation="LaTeX">\cdot </tex-math></inline-formula>dL<inline-formula> <tex-math notation="LaTeX">^{-1} </tex-math></inline-formula>. The experimental results show that the amplitude changes 32.1 dB, and the phase changes 60.88° at 1 GHz. The results indicate the proposed microwave sensor has an excellent biosensing performance.
Metal halide perovskites have attracted much attention in biomedicine because of their excellent fluorescence energy conversion properties; however, poor water-stability and cytotoxicity limit its ...applications as a biomedical tracer, especially in cellular imaging. Herein, water-ultrastable perovskites CsPbBr
3
:Cs
4
PbBr
6
nanocrystals (NCs) encapsulated in chitosan are fabricated successfully using a water-triggered method. The as-synthesized CsPbBr
3
:Cs
4
PbBr
6
@CS (chitosan, CS) nanoparticles in water display enhanced fluorescence emission for 35 days. Further, the viability of glioma cells (U87 cells) incubated with different concentrations of CsPbBr
3
:Cs
4
PbBr
6
@CS nanoparticles (0–20 μg·ml
−1
) for 24 h is found to be higher than 90%. In artificial body fluid, analyses using laser confocal microscopy, the standard Cell Counting Kit-8 (CCK-8) method, and flow cytometry demonstrated the good water ultrastability and high biocompatibility performance of CsPbBr
3
:Cs
4
PbBr
6
@CS nanoparticles in cellular imaging. Overall, the water-ultrastable halide perovskites support promising perspectives in biological cell tracing and intelligent medical technology.
Graphical Abstract
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Two generations of garnet are recognized in a granite and a pegmatite from the Gangdese orogen in southeastern Tibet on the basis of a combined study of petrography, major and trace element profiles, ...and garnet O isotopes. Zircon U-Pb dating and Hf-O isotope compositions also help constrain the origin of both granite and pegmatite. The first generation of garnet (Grt-I) occurs as residues in the center of garnet grains, and it represents an early stage of nucleation related to magmatic-hydrothermal fluids. Grt-I is dark in backscattered electron (BSE) images, rich in spessartine, and poor in almandine and grossular. Its chondrite-normalized rare earth element (REE) patterns show obvious negative Eu anomalies and depletion in heavy REE (HREE) relative to middle REE (MREE). The second generation of pegmatite garnet (Grt-II) occurs as rims of euhedral garnets or as patches in Grt-I domains of the pegmatite, and it crystallized after dissolution of the preexisting pegmatite garnet (Grt-I domains) in the presence of the granitic magma. Compared with Grt-I, Grt-II is bright in BSE images, poor in spessartine, and rich in almandine and grossular contents. Its chondrite-normalized REE patterns exhibit obvious negative Eu anomalies but enrichment in HREE relative to MREE. The elevation of grossular and HREE contents for Grt-II relative to Grt-I domains indicate that the granitic magma had higher contents of Ca than the magmatic-hydrothermal fluids. The garnets in the granite, from core to rim, display homogenous profiles in their spessartine, almandine, and pyrope contents but increasing grossular and decreasing REE contents. They are typical of magmatic garnets that crystallized from the granitic magma. Ti-in-zircon temperatures demonstrate that the granite and pegmatite may share the similar temperatures for their crystallization. Grt-II domains in the pegmatite garnet have the same major and trace element compositions as the granite garnet, suggesting that the pegmatite Grt-II domains crystallized from the same granitic magma. Therefore, the pegmatite crystallized at first from early magmatic-hydrothermal fluids, producing small amounts of Grt-I, and the fluids then mixed with the surrounding granitic magma. The U-Pb dating and Hf-O isotope analyses of zircons from the granite and pegmatite yield almost the same U-Pb ages of 77-79 Ma, positive εHf(t) values of 5.6 to 11.9, and δ18O values of 5.2 to 7.1 ppm. These data indicate that the granite and pegmatite were both derived from reworking of the juvenile crust in the newly accreted continental margin prior to the continental collision in the Cenozoic.
Accumulating evidence has shown that chronic injection of
d
-galactose (
d
-gal) can mimic natural aging, with accompanying liver and brain injury. Oxidative stress and apoptosis play a vital role in ...the aging process. In this study, the antioxidant ability of polydatin (PD) was investigated using four established
in vitro
systems. An
in vivo
study was also conducted to investigate the possible protective effect of PD on
d
-gal-induced liver and brain damage. The results showed that PD had remarkable
in vitro
free radical scavenging activity on 2,2-diphenyl-1-picryl-hydrazyl (DPPH&z.rad;), 2,2′-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS
+
&z.rad;) radical ions, and hydroxyl and superoxide anions. Results
in vivo
indicated that, in a group treated with
d
-gal plus PD, PD remarkably decreased the depression of body weight and organ indexes, reduced the levels of the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and alleviated alterations in liver and brain histopathology. PD also significantly decreased the level of MDA and elevated SOD, GSH-Px, CAT activity and T-AOC levels in the liver and brain. In addition, the levels of inflammatory mediators, such as TNF-α, IL-1β and IL-6 in serum were markedly reduced after PD treatment. Western blotting results revealed that PD treatment noticeably attenuated the
d
-gal-induced elevation of Bcl-2/Bax ratio and caspase-3 protein expression in liver and brain. Overall, our findings indicate that PD treatment could effectively attenuate
d
-gal-induced liver and brain damage, and the mechanism might be associated with decreasing the oxidative stress, inflammation and apoptosis caused by
d
-gal. PD holds good potential for further development into a promising pharmaceutical candidate for the treatment of age-associated diseases.
Accumulating evidence has shown that chronic injection of
d
-galactose (
d
-gal) can mimic natural aging, with accompanying liver and brain injury.
Reactive oxygen species (ROS) production is essential for both physiological processes and environmental stress in diverse plants. Previous studies have found that benzo-(1, 2, ...3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH)-inducible ROS were associated with wound healing of potato tubers. Calcium-dependent protein kinases (CDPKs), the important calcium receptors, are known to play a crucial part in plant development and adaptation to abiotic stresses. However, whether CDPK-mediated ROS generation induced by BTH is involved in wound healing is elusive. In this study, we measured
Solanum tuberosum CDPKs
(
StCDPKs
) expression using real-time PCR, and it was found that the transcriptional levels of
StCDPKs
from BTH-treated tissues were significantly induced, among which
StCDPK14
presented the most increased level. Subcellular localization results showed that StCDPK14 is located in the nucleus and membrane. The transgenic potato plants and tubers were developed using interference-expression of
StCDPK14
by
Agrobacterium tumefaciens
–mediated transformation. The
St
respiratory burst oxidase homologs (
StRbohs
) expression showed a remarkable decrease in
StCDPK14
transgenic tubers, notably, H
2
O
2
content and suberin deposition were also significantly declined. To confirm the relationship between StCDPK14 and StRbohB, yeast-two-hybrid and bimolecular fluorescence complementation were used to examine the interaction, and it was shown that StCDPK14 interacted with the specific Ca
2 +
-binding motif (helix-loop-helix, called EF-hand) of StRbohB N-terminus. The above results unraveled that StCDPK14 functions in ROS generation
via
interacting with StRbohB during wound healing of potato tubers.
To investigate the feasibility of enhanced computed tomography (CT) radiomics analysis to differentiate between pancreatic cancer (PC) and chronic pancreatitis.
The CT images of 151 PCs and 24 ...chronic pancreatitis were retrospectively analyzed in the three-dimensional regions of interest on arterial phase (AP) and venous phase (VP) and segmented by MITK software. A multivariable logistic regression model was established based on the selected radiomics features. The radiomics score was calculated, and the nomogram was established. The discrimination of each model was analyzed by the receiver operating characteristic curve (ROC). Decision curve analysis (DCA) was used to evaluate clinical utility. The precision recall curve (PRC) was used to evaluate whether the model is affected by data imbalance. The Delong test was adopted to compare the diagnostic efficiency of each model.
Significant differences were observed in the distribution of gender (
= 0.034), carbohydrate antigen 19-9 (
< 0.001), and carcinoembryonic antigen (
< 0.001) in patients with PC and chronic pancreatitis. The area under the ROC curve (AUC) value of AP multivariate regression model, VP multivariate regression model, AP combined with VP features model (Radiomics), clinical feature model, and radiomics combined with clinical feature model (COMB) was 0.905, 0.941, 0.941, 0.822, and 0.980, respectively. The sensitivity and specificity of the COMB model were 0.947 and 0.917, respectively. The results of DCA showed that the COMB model exhibited net clinical benefits and PRC shows that COMB model have good precision and recall (sensitivity).
The COMB model could be a potential tool to distinguish PC from chronic pancreatitis and aid in clinical decisions.
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