Joint learning of nonlinear representation and projection for fast constrained MRSI reconstruction.

Purpose: To develop and evaluate a novel method for computationally efficient reconstruction from noisy MR spectroscopic imaging (MRSI) data.

Methods: The proposed method features (a) a novel strategy that jointly learns a nonlinear low-dimensional representation of high-dimensional spectroscopic signals and a neural-network-based projector to recover the low-dimensional embeddings from noisy/limited data; (b) a formulation that integrates the forward encoding model, a regularizer exploiting the learned representation, and a complementary spatial constraint; and (c) a highly efficient algorithm enabled by the learned projector within an alternating direction method of multipliers (ADMM) framework, circumventing the computationally expensive network inversion subproblem.

Results: The proposed method has been evaluated using simulations as well as in vivo H and P MRSI data, demonstrating improved performance over state-of-the-art methods, with about 6 fewer averages needed than standard Fourier reconstruction for similar metabolite estimation variances and up to 100 reduction in processing time compared to a prior neural network constrained reconstruction method.

Simple cyclic chalcone dye with multiple optical functions: Piezochromism and lysosomes staining.

Both artificially synthesized and naturally occurring cyclic chalcones have been widely studied for their excellent biological activities. However, research on its photophysical properties is still limited. In the present study, we designed and synthesized a small molecule fluorescent dye based on the ICT effect, using dimethylamino as the electron-donating group and carbonyl as the electron withdrawing group, and investigated its photophysical properties in depth.

Multi-Parametric Molecular Imaging of the Brain Using Optimized Multi-TE Subspace MRSI.

Objective: To develop a novel multi-TE MR spectroscopic imaging (MRSI) approach to enable label-free, simultaneous, high-resolution mapping of several molecules and their biophysical parameters in the brain.

Methods: The proposed method uniquely integrated an augmented molecular-component-specific subspace model for multi-TE H-MRSI signals, an estimation-theoretic experiment optimization (nonuniform TE selection) for molecule separation and parameter estimation, a physics-driven subspace learning strategy for spatiospectral reconstruction and molecular quantification, and a new accelerated multi-TE MRSI acquisition for generating high-resolution data in clinically relevant times. Numerical studies, phantom and in vivo experiments were conducted to validate the optimized experiment design and demonstrate the imaging capability offered by the proposed method.

High-resolution, 3D multi-TE H MRSI using fast spatiospectral encoding and subspace imaging.

Purpose: To develop a novel method to achieve fast, high-resolution, 3D multi-TE H-MRSI of the brain.

Methods: A new multi-TE MRSI acquisition strategy was developed that integrates slab selective excitation with adiabatic refocusing for better volume coverage, rapid spatiospectral encoding, sparse multi-TE sampling, and interleaved water navigators for field mapping and calibration. Special data processing strategies were developed to interpolate the sparsely sampled data, remove nuisance signals, and reconstruct multi-TE spatiospectral distributions with high SNR.

TiO Nano-test tubes as a solid visual platform for sensitive Pb ion detection based on a fluorescence resonance energy transfer (FRET) process.

A cost-effective, facile, and sensitive fluorescence sensing strategy for Pb ion detection has been developed based on the fluorescence resonance energy transfer (FRET) between carbon quantum dots (CQDs) and Au nanoparticles (NPs). Glutathione (GSH)-synthesized CQDs acted as both the fluorescence donor and the sorbent to extract Pb ions from the solution via Pb-GSH complexes. Pb ions on CQDs reacted with -SH groups on AuNPs to generate sandwich-type Au-PdS-CQDs, leading to a dramatic decrease in the fluorescence of the CQDs.

Introducing graphitic carbon nitride nanosheets as supersandwich-type assembly on porous electrode for ultrasensitive electrochemiluminescence immunosensing.

Biomarkers in blood or tissue provide essential information for clinical screening and early disease diagnosis. However, increasing the sensitivity of detecting biomarkers remains a major challenge in a wide variety of electrochemical immunoassays. Herein, we present an electrochemiluminescence (ECL) immunosensing strategy with 1: N amplification ratio (target-to-signal probe) for biomarkers detection on a porous gold electrode.

A portable dual-mode sensor based on a TiO nanotube membrane for the evaluation of telomerase activity.

A portable dual-mode sensing platform based on a self-standing TiO2 nanotube membrane is developed for simultaneously performing both qualitative analysis by the naked eye and quantitative analysis by ionic current. This dual-mode diagnosis strategy exhibits a high performance in telomerase detection in urine specimens from patients with bladder cancer.

Protein Shell-Encapsulated Pt Clusters as Continuous O-Supplied Biocoats for Photodynamic Therapy in Hypoxic Cancer Cells.

As a highly oxygen-dependent process, the effect of photodynamic therapy is often obstructed by the premature leakage of photosensitizers and the lack of oxygen in hypoxic cancer cells. To overcome these limitations, this study designs bovine serum albumin protein (BSA)-encapsulated Pt nanoclusters (PtBSA) as O-supplied biocoats and further incorporates them with mesoporous silica nanospheres to develop intelligent nanoaggregates for achieving improved therapeutic outcomes against hypoxic tumors. The large number of amino groups on BSA can provide sufficient functional groups to anchor tumor targeting agents and thus enhance the selective cellular uptake efficiency.

Nitrogen-doped carbon nanospheres derived from cocoon silk as metal-free electrocatalyst for glucose sensing.

Nitrogen-doped carbon materials have attracted tremendous attention because of their high activity in electrocatalysis. In the present work, cocoon silk -- a biomass material is used to prepare porous carbon fibers due to its abundant nitrogen content. The as-prepared carbon microfibers have been activated and disintegrated into carbon nanospheres (CNS) with a diameter of 20--60 nm by a simple nitric acid refluxing process.

Carbon cladded TiO2 nanotubes: fabrication and use in 3D-RuO2 based supercapacitors.

In this work we introduce a facile procedure that allows a highly conformal coating of self-organized TiO2 nanotubes (NTs) with a graphite-like thin carbon layer. This provides a platform to enhance the functionality of TiO2 nanotubes for a wide range of applications. Here we show that such modified nanotubes can serve as a 3D scaffold for an ideal decoration with RuO2 nanoparticles.