67 research outputs found
Recent Advances in Liver Engineering With Decellularized Scaffold
Liver transplantation is currently the only effective treatment for patients with end-stage liver disease; however, donor liver scarcity is a notable concern. As a result, extensive endeavors have been made to diversify the source of donor livers. For example, the use of a decellularized scaffold in liver engineering has gained considerable attention in recent years. The decellularized scaffold preserves the original orchestral structure and bioactive chemicals of the liver, and has the potential to create a de novo liver that is fit for transplantation after recellularization. The structure of the liver and hepatic extracellular matrix, decellularization, recellularization, and recent developments are discussed in this review. Additionally, the criteria for assessment and major obstacles in using a decellularized scaffold are covered in detail
Fabrication and Characterization of Al/NiO Energetic Nanomultilayers
The redox reaction between Al and metallic oxide has its advantage compared with intermetallic reaction and Al/NiO nanomutlilayers are a promising candidate for enhancing the performance of energetic igniter. Al/NiO nanomutlilayers with different modulation periods are prepared on alumina substrate by direct current (DC) magnetron sputtering. The thicknesses of each period are 250 nm, 500 nm, 750 nm, 1000 nm, and 1500 nm, respectively, and the total thickness is 3 μm. The X-ray diffraction (XRD) and scanning electron microscope (SEM) results of the as-deposited Al/NiO nanomutlilayers show that the NiO films are amorphous and the layered structures are clearly distinguished. The X-ray photoelectron spectroscopy (XPS) demonstrates that the thickness of Al2O3 increases on the side of Al monolayer after annealing at 450°C. The thermal diffusion time becomes greater significantly as the amount of thermal boundary conductance across the interfaces increases with relatively smaller modulation period. Differential scanning calorimeter (DSC) curve suggests that the energy release per unit mass is below the theoretical heat of the reaction due to the nonstoichiometric ratio between Al and NiO and the presence of impurities
Predicting Axillary Lymph Node Metastasis in Early Breast Cancer Using Deep Learning on Primary Tumor Biopsy Slides
Objectives: To develop and validate a deep learning (DL)-based primary tumor
biopsy signature for predicting axillary lymph node (ALN) metastasis
preoperatively in early breast cancer (EBC) patients with clinically negative
ALN.
Methods: A total of 1,058 EBC patients with pathologically confirmed ALN
status were enrolled from May 2010 to August 2020. A DL core-needle biopsy
(DL-CNB) model was built on the attention-based multiple instance-learning
(AMIL) framework to predict ALN status utilizing the DL features, which were
extracted from the cancer areas of digitized whole-slide images (WSIs) of
breast CNB specimens annotated by two pathologists. Accuracy, sensitivity,
specificity, receiver operating characteristic (ROC) curves, and areas under
the ROC curve (AUCs) were analyzed to evaluate our model.
Results: The best-performing DL-CNB model with VGG16_BN as the feature
extractor achieved an AUC of 0.816 (95% confidence interval (CI): 0.758, 0.865)
in predicting positive ALN metastasis in the independent test cohort.
Furthermore, our model incorporating the clinical data, which was called
DL-CNB+C, yielded the best accuracy of 0.831 (95%CI: 0.775, 0.878), especially
for patients younger than 50 years (AUC: 0.918, 95%CI: 0.825, 0.971). The
interpretation of DL-CNB model showed that the top signatures most predictive
of ALN metastasis were characterized by the nucleus features including density
( = 0.015), circumference ( = 0.009), circularity ( = 0.010), and
orientation ( = 0.012).
Conclusion: Our study provides a novel DL-based biomarker on primary tumor
CNB slides to predict the metastatic status of ALN preoperatively for patients
with EBC. The codes and dataset are available at
https://github.com/bupt-ai-cz/BALNMPComment: Update Table 1 and corresponding description
Characteristics of the Energetic Igniters Through Integrating Al/NiO Nanolaminates on Cr Film Bridge
Integrated Temperature and Hydrogen Sensors with MEMS Technology
In this work, a PdNi thin film hydrogen gas sensor with integrated Pt thin film temperature sensor was designed and fabricated using the micro-electro-mechanical system (MEMS) process. The integrated sensors consist of two resistors: the former, based on Pt film, is used as a temperature sensor, while the latter had the function of hydrogen sensing and is based on PdNi alloy film. The temperature coefficient of resistance (TCR) in both devices was measured and the output response of the PdNi film hydrogen sensor was calibrated based on the temperature acquired by the Pt temperature sensor. The SiN layer was deposited on top of Pt film to inhibit the hydrogen diffusion and reduce consequent disturbance on temperature measurement. The TCR of the PdNi film and the Pt film was about 0.00122/K and 0.00217/K, respectively. The performances of the PdNi film hydrogen sensor were investigated with hydrogen concentrations from 0.3% to 3% on different temperatures from 294.7 to 302.2 K. With the measured temperature of the Pt resistor and the TCR of the PdNi film, the impact of the temperature on the performances of the PdNi film hydrogen sensor was reduced. The output response, response time and recovery time of the PdNi film hydrogen sensors under the hydrogen concentration of 0.5%, 1.0%, 1.5% and 2.0% were measured at 313 K. The output response of the PdNi thin film hydrogen sensors increased with increasing hydrogen concentration while the response time and recovery time decreased. A cycling test between pure nitrogen and 3% hydrogen concentration was performed at 313 K and PdNi thin film hydrogen sensor demonstrated great repeatability in the cycling test
Positive solutions to singular Dirichlet-type boundary value problems of nonlinear fractional differential equations
Abstract In this paper, by using the properties of the Green function, u0 -positive operator and Gelfand’s formula, some properties of the first eigenvalue corresponding to the relevant operator are obtained. Based on these properties, the fixed point index of the nonlinear operator is calculated explicitly and some sufficient conditions for the existence and uniqueness results of positive solution are established
Positive Solutions for Higher Order Nonlocal Fractional Differential Equation with Integral Boundary Conditions
In this paper, by using the spectral analysis of the relevant linear operator and Gelfand’s formula, some properties of the first eigenvalue of a fractional differential equation were obtained; combining fixed point index theorem, sufficient conditions for the existence of positive solutions are established. An example is given to demonstrate the application of our main results
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