Non-Negative Matrix Factorization Based on Smoothing and Sparse Constraints for Hyperspectral Unmixing.

Hyperspectral unmixing (HU) is a technique for estimating a set of pure source signals (end members) and their proportions (abundances) from each pixel of the hyperspectral image. Non-negative matrix factorization (NMF) can decompose the observation matrix into the product of two non-negative matrices simultaneously and can be used in HU. Unfortunately, a limitation of many traditional NMF-based methods, i.e., the non-convexity of the objective function, may lead to a sub-optimal solution. Thus, we put forward a new unmixing method based on NMF under smoothing and sparse constraints to obtain a better solution. First, considering the sparseness of the abundance matrix, a weight sparse regularization is introduced into the NMF model to ensure the sparseness of the abundance matrix. Second, according to the similarity prior of the same feature in the adjacent pixels, a Total Variation regularization is further added to the NMF model to improve the smoothness of the abundance map. Finally, the signatures of each end member are modified smoothly in spectral space. Moreover, it is noticed that discontinuities may emerge due to the removal of noisy bands. Therefore, the spectral data are piecewise smooth in spectral space. Then, in this paper, a piecewise smoothness constraint is further applied to each column of the end-member matrix. Experiments are conducted to evaluate the effectiveness of the proposed method based on two different datasets, including a synthetic dataset and the real-life Cuprite dataset, respectively. Experimental results show that the proposed method outperforms several state-of-the-art HU methods. In the Cuprite hyperspectral dataset, the proposed method's Spectral Angle Distance is 0.1694, compared to the TV-RSNMF method's 0.1703, L1/2NMF method's 0.1925, and VCA-FCLS method's 0.1872.

Dual-target Janus kinase (JAK) inhibitors: Comprehensive review on the JAK-based strategies for treating solid or hematological malignancies and immune-related diseases.

Janus kinases (JAKs) are the non-receptor tyrosine kinases covering JAK1, JAK2, JAK3, and TYK2 which regulate signal transductions of hematopoietic cytokines and growth factors to play essential roles in cell growth, survival, and development. Dysregulated JAK activity leading to a constitutively activated signal transducers and activators of transcription (STAT) is strongly associated with immune-related diseases and cancers. Targeting JAK to interfere the signaling of JAK/STAT pathway has achieved quite success in the treatment of these diseases. However, inadequate clinical response and serious adverse events come along by the treatment of monotherapy of JAK inhibitors. With better and deeper understanding of JAK/STAT pathway in the pathogenesis of diseases, researchers start to show huge interest in combining inhibition of JAK and other oncogenic targets to realize a broader regulation on pathological processes to block disease development and progression, which has hastened extensive research of dual JAK inhibitors over the past decades. Until now, studies of dual JAK inhibitors have added BTK, SYK, FLT3, HDAC, Src, and Aurora kinases to the overall inhibitory profile and demonstrated significant advantage and superiority over single-target inhibitors. In this review, we elucidated the possible mechanism of synergic effects caused by dual JAK inhibitors and briefly describe the development of these agents.

Water insoluble and flexible transparent film based on carboxymethyl cellulose.

Preparation of renewable, insoluble, and transparent films is still a major challenge for the application of soft electronics and packing industry. Herein, a "green" protocol for preparation of such a film based on carboxymethyl cellulose (CMC) is presented, where acid assistant freeze-thaw method was used in combination with drying. We have shown that the resultant films displayed flexibility, high light transmittance (above 90 %), insolubility, high mechanical performances (elastic modulus of 29.6 MPa), and good thermal stability. Moreover, CMC film/filter paper was fabricated, and the waterproof and mechanical properties of which were investigated. This approach offers a promising route to the fabrication of flexible and transparent films with good waterproof properties based on soluble biomass.

Synthesis of 6-O-poly(ϵ-caprolactone)-L-ascorbic acid and its controlled release from supramolecular polymer micelles.

Lipophilic 6-O-poly (ϵ-caprolactone)-L-ascorbic acid (AA-6-PCL) is synthesized through ROP of ϵ-caprolactone (CL). The number of repeating CL units in the polymer chain varies from 6 to 19. AA-6-PCL loaded supramolecular polymer micelles (SMPMs) are constructed with ß-cyclodextrin (ß-CD) and PCL as blocks. Transmission electron microscopy images show a nanospheric morphology of the micelles with a size range of 43.3 ± 5.0 nm. The drug loading contents are 22.53-39.23% for AA-6-PCL. AA-6-PCL exhibits high radical scavenging capacity (93.96-96.73%) and efficient scavenging potency, and a cytotoxicity study proves the excellent cytocompatibility of AA-6-PCL loaded ß-CD/PCL SMPMs, which altogether herald their potential application in the study of the induced pluripotent stem cells.

Host-guest chemistry of cyclodextrin carbamates and cellulose derivatives in aqueous solution.

Supramolecular polymer micelles were prepared on basis of the inclusion complexation between cyclodextrin carbamates and cellulose derivatives in aqueous media. Cyclodextrin carbamates were synthesized by microwave-assisted method from cyclodextrin and urea. The urea modified cyclodextrin shows the higher yield than the physical mixture of urea/cyclodextrin in the micellization with cellulose derivatives. The supramolecular structure of the core-shell micelles was demonstrated by (1)H NMR spectra, TEM images, and fluorescence spectra. The drug release behavior of the supramolecular polymer micelles was evaluated using prednisone acetate as a model drug. The drug loaded micelles showed steady and long time drug release behavior. With these properties, the supramolecular polymer micelles are attractive as drug carriers for pharmaceutical applications.

Biopolymer-based supramolecular micelles from ß-cyclodextrin and methylcellulose.

Supramolecular polymer micelles (SMPMs) were constructed from natural and natural-derived polymers: ß-cyclodextrin (ß-CD)/maleic anhydride modified ß-cyclodextrin (MAh-ß-CD) and methylcellulose (MC) in aqueous solution by one-pot self-assembly procedure, in which, ß-CD and MAh-ß-CD inclusion complexes were used as the hydrophilic shell and the free MC as the core. The shapes of the SMPMs were regular spheres with diameters of 25±5 nm. The critical micelle concentrations, calculated from steady-state fluorescence emission spectra, were around 15.13 and 20.89 mg/L for MC/ß-CD and MC/MAh-ß-CD SMPMs, respectively. The in vitro drug release behaviors of the micelles were studied using prednisone acetate as a model drug, and the results showed that the MC/MAh-ß-CD micelle had a drug-enrichment core and excellent drug released behaviors with a sustaining release time of 700 h.