5 research outputs found
A Generative Modeling Framework for Inferring Families of Biomechanical Constitutive Laws in Data-Sparse Regimes
Quantifying biomechanical properties of the human vasculature could deepen
our understanding of cardiovascular diseases. Standard nonlinear regression in
constitutive modeling requires considerable high-quality data and an explicit
form of the constitutive model as prior knowledge. By contrast, we propose a
novel approach that combines generative deep learning with Bayesian inference
to efficiently infer families of constitutive relationships in data-sparse
regimes. Inspired by the concept of functional priors, we develop a generative
adversarial network (GAN) that incorporates a neural operator as the generator
and a fully-connected neural network as the discriminator. The generator takes
a vector of noise conditioned on measurement data as input and yields the
predicted constitutive relationship, which is scrutinized by the discriminator
in the following step. We demonstrate that this framework can accurately
estimate means and standard deviations of the constitutive relationships of the
murine aorta using data collected either from model-generated synthetic data or
ex vivo experiments for mice with genetic deficiencies. In addition, the
framework learns priors of constitutive models without explicitly knowing their
functional form, providing a new model-agnostic approach to learning hidden
constitutive behaviors from data
Cryoprotective Roles of Carboxymethyl Chitosan during the Frozen Storage of Surimi: Protein Structures, Gel Behaviors and Edible Qualities
Carboxymethyl chitosan (CMCh) is an ampholytic chitosan derivative that manifests versatile applications in food industry, such as antibacterial ingredients and nutritional additives. However, its use as a cryoprotectant remains under-researched. In this study, the cryoprotective effect of CMCh oligosaccharide (CMCO) on frozen surimi (silver carp) was systematically investigated in terms of protein structures, gelling behaviors, and sensory qualities. CMCO (0.6%) was incorporated in the surimi before frozen storage (−18 °C for 60 days) while the commercial cryoprotectant (4% sucrose, 4% sorbitol) was used as a positive control. Results indicated that CMCO could inhibit the freezing-induced denaturation of myofibrillar protein, whose values of solubility, Ca2+-ATPase and sulfhydryl content were 24.8%, 64.7%, and 17.1% higher than the nonprotected sample, respectively, while the surface hydrophobicity was 21.6% lower. Accordingly, CMCO stabilized microstructure of the surimi gels associated with improved gel strength, viscoelasticity, water-holding capacities, and whiteness. Moreover, the cryoprotective effect of CMCO with higher degree of carboxymethyl substitution (DS: 1.2) was more pronounced than that of low-DS-CMCO (DS: 0.8). Frozen surimi treated with high-DS-CMCO achieved competitive gelling properties and sensory acceptability to those with the commercial counterpart. This study provided scientific insights into the development of ampholytic oligosaccharides as food cryoprotectants
NTIRE 2022 Challenge on Stereo Image Super-Resolution: Methods and Results
In this paper, we summarize the 1st NTIRE challenge on stereo image super-resolution (restoration of rich details in a pair of low-resolution stereo images) with a focus on new solutions and results. This challenge has 1 track aiming at the stereo image super-resolution problem under a standard bicubic degradation. In total, 238 participants were successfully registered, and 21 teams competed in the final testing phase. Among those participants, 20 teams successfully submitted results with PSNR (RGB) scores better than the baseline. This challenge establishes a new benchmark for stereo image SR