42 research outputs found
Statistical Optimality of Deep Wide Neural Networks
In this paper, we consider the generalization ability of deep wide
feedforward ReLU neural networks defined on a bounded domain . We first demonstrate that the generalization ability of
the neural network can be fully characterized by that of the corresponding deep
neural tangent kernel (NTK) regression. We then investigate on the spectral
properties of the deep NTK and show that the deep NTK is positive definite on
and its eigenvalue decay rate is . Thanks to the well
established theories in kernel regression, we then conclude that multilayer
wide neural networks trained by gradient descent with proper early stopping
achieve the minimax rate, provided that the regression function lies in the
reproducing kernel Hilbert space (RKHS) associated with the corresponding NTK.
Finally, we illustrate that the overfitted multilayer wide neural networks can
not generalize well on . We believe our technical contributions
in determining the eigenvalue decay rate of NTK on might be of
independent interests
Huge myxoid chondrosarcoma expanded into the thoracic cavity with spinal involvement
En bloc resection is the treatment of choice of myxoid chondrosarcoma. These tumors can produce huge masses. Anatomical constraints limit the possibility to perform en bloc resection in the spine. A very huge myxoid chondrosarcoma (14.2 × 10.8 × 11.4 cm) arising from T2 to T5 and invading the whole higher left pleural cavity was observed. Surgical planning according to WBB staging system was performed. The tumor was successfully submitted to en bloc resection achieving a tumor-free margin as demonstrated by the pathologist's report. A careful planning and a multidisciplinary collaboration make possible to perform en bloc resection even in apparently impossible cases
Temperature Homogenization of Co-Integrated Shape Memory—Silicon Bimorph Actuators
The high work density and beneficial downscaling of shape memory alloy (SMA) actuation performance provide a basis for the development of actuators and systems at microscales. Here, we report a novel monolithic fabrication approach for the co-integration of SMA and Si microstructures to enable SMA-Si bimorph microactuation. Double-beam cantilevers are chosen for the actuator layout to enable electrothermal actuation by Joule heating. The SMA materials under investigation are NiMnGa and NiTi(Hf) films with tunable phase transformation temperatures. We show that Joule heating of the cantilevers generates increasing temperature gradients for decreasing cantilever size, which hampers actuation performance. In order to cope with this problem, a new method for design optimization is presented based on finite element modeling (FEM) simulations. We demonstrate that temperature homogenization can be achieved by the design of additional folded beams in the perpendicular direction to the active beam cantilevers. Thereby, power consumption can be reduced by more than 35 % and maximum deflection can be increased up to a factor of 2 depending on the cantilever geometry
Targeted therapy of RET fusion-positive non-small cell lung cancer
Lung cancer has very high morbidity and mortality worldwide, and the prognosis is not optimistic. Previous treatments for non-small cell lung cancer (NSCLC) have limited efficacy, and targeted drugs for some gene mutations have been used in NSCLC with considerable efficacy. The RET proto-oncogene is located on the long arm of chromosome 10 with a length of 60,000 bp, and the expression of RET gene affects cell survival, proliferation, growth and differentiation. This review will describe the basic characteristics and common fusion methods of RET genes; analyze the advantages and disadvantages of different RET fusion detection methods; summarize and discuss the recent application of non-selective and selective RET fusion-positive inhibitors, such as Vandetanib, Selpercatinib, Pralsetinib and Alectinib; discuss the mechanism and coping strategies of resistance to RET fusion-positive inhibitors
Poly(2-(diethylamino)ethyl methacrylate)-based, pH-responsive, copolymeric mixed micelles for targeting anticancer drug control release
Process of Extraction Protein from Selenium-enriched Lyophyllum decastes Mycelia and Analysis of Its Amino Acid
The process of extracting seleno-protein from the selenium enriched Lyophyllum decastes mycelia cultured in a 20 L fermentor was optimized, and the effects of selenium enrichment on both types and contents of amino acids in Lyophyllum decastes mycelia were analyzed. Single factor tests and Box-Benhnken central combined response surface test were used to optimize process of extracting seleno-protein from Lyophyllum decastes mycelia. The content of protein was determined by 3,3'-diaminobenzidine spectrophotometry. The types and contents of amino acids in mycelia protein before and after selenium enrichment were compared by means of amino acid analyzer. The results showed that the optimal conditions of extracting seleno-protein from mycelia of Lyophyllum decastes were extraction temperature of 64 ℃, extraction time of 60 min, liquid-solid ratio of 200:1 g/mL, and extraction times of 2. The protein extraction rate was 75.13%, and the content of selenium in mycelia was 63.87 μg/g. The amino acid composition were analyzed by means amino acid score (AAS) and chemical score (CS), and the nutritional value of the protein in the selenium-enriched Lyophyllum decastes mycelia was evaluated. The varieties of amino acids in the selenium-enriched Lyophyllum decastes mycelia were abundant and the content of essential amino acids for human body was 17.20 g/100 g, 19.75% higher than that in the non-selenium-ecriched Lyophyllum decastes mycelia. The ratio of EAA/NEAA was 0.51, close to the recommended value proposed by WHO, and the values of both AAS and CS were close to the those in the model protein. In summary, the protein extraction rate could be improved by optimizing the extraction process, and there was selenium in the protein from selenium-enriched mycelia, which promoted the increase of amino acid content. The nutritional value of protein in selenium-enriched mycelia was higher than that in non-selenium-riched mycelia, and selenium-enrichec mycelia had potential edible and application value
Rare Copy Number Variants Identify Novel Genes in Sporadic Total Anomalous Pulmonary Vein Connection
Total anomalous pulmonary venous connection (TAPVC) is a rare congenital heart anomaly. Several genes have been associated TAPVC but the mechanisms remain elusive. To search novel CNVs and candidate genes, we screened a cohort of 78 TAPVC cases and 100 healthy controls for rare copy number variants (CNVs) using whole exome sequencing (WES). Then we identified pathogenic CNVs by statistical comparisons between case and control groups. After that, we identified altogether eight pathogenic CNVs of seven candidate genes (PCSK7, RRP7A, SERHL, TARP, TTN, SERHL2, and NBPF3). All these seven genes have not been described previously to be related to TAPVC. After network analysis of these candidate genes and 27 known pathogenic genes derived from the literature and publicly database, PCSK7 and TTN were the most important genes for TAPVC than other genes. Our study provides novel candidate genes potentially related to this rare congenital birth defect (CHD) which should be further fundamentally researched and discloses the possible molecular pathogenesis of TAPVC