No abstract

In this paper, the UDE (uncertainty and disturbance estimator)-based robust control is applied to the control of a class of non-affine nonlinear systems. This class of systems is very general and covers a large range of nonlinear systems. However, the control of such systems is very challenging because the input variables are not expressed in an affine form, which leads to the failure of using feedback linearization. The proposed UDEbased control method avoids the "inverse operator" construction which might result in the control singularity problem. Moreover, the general assumption on the uncertainty and disturbance term is relaxed and only its bandwidth information is required for the control design. The asymptotic stability of the closedloop system is established. The proposed approach is easy to be implemented and tuned while bringing very good robust performance. The important features and performance of the proposed approach are demonstrated through both simulation studies and experimental validation on a servo system with nonaffine uncertainties.

The oncogenic transcription factor c-Maf has been proposed as an ideal therapeutic target for multiple myeloma (MM) but how to achieve it is still elusive. In the present study we found the Otub1/c-Maf axis could be a potential target. Otub1, an OTU family deubiquitinase, was found to interact with c-Maf by mass spectrometry. Otub1 abrogates c-Maf K48-linked polyubiquitination thus preventing its degradation and enhancing its transcriptional activity. Specifically, this deubiquitinating activity depends on its Lys71 and the N-terminus but independent UBE2O, a known E2 of c-Maf. Otub1 promotes MM cell survival and MM tumor growth. In contrast, silence of Otub1 leads to c-Maf degradation and c-Maf-expressing MM cell apoptosis. Therefore, the Otub1/c-Maf axis could be a therapeutic target of MM. In order to explore this concept, we performed a c-Maf-recognition element-driven luciferase-based screen against FDA-approved drugs and natural products, from which the generic cardiac glycoside lanatoside C (LanC) is found to prevent c-Maf de-ubiquitination and induces its degradation by disrupting the interaction of Otub1 and c-Maf. Consequently, LanC inhibits c-Maf transcriptional activity, induces c-Maf-expressing MM cell apoptosis, and suppresses MM growth and prolongs overall survival of model mice but without apparent toxicity. Therefore, the present study identifies Otub1 as a novel deubiquitinase of c-Maf and establishes that the Otub1/c-Maf axis is a potential therapeutic target for MM.

Hydrogels are excellent for protecting membranes from oil fouling for oil/water separation. However, conventional hydrogels including adhesive hydrogels have a contradictory between high adhesion on membranes and anti‐oil‐fouling ability. Herein, the design of an adhesive hydrogel on membranes is proposed by ingeniously integrating high adhesion on membranes, outstanding anti‐oil‐fouling ability, ultrathin thickness suitable for membrane decoration and satisfactory durability, where an inside‐out gradient distribution of adhesive protocatechuic acid (PCA) and hydrated calcium alginate (CaAlg) on membranes is constructed. The innermost PCA enables the adhesive hydrogel to tightly adhere to the membranes. The outermost CaAlg defends membranes from oil fouling. The gradient distribution and uniform integration of PCA/CaAlg guarantee an excellent stability. Membranes decorated with the adhesive hydrogel demonstrate superhydrophilicity,  anti‐fouling to various oils, and anti‐abrasion to external damaging. The membranes achieve ultra‐stable and efficient separation of surfactant‐stabilized oil‐in‐water emulsions and crude oil/water mixture with the most advanced cycling ability of ≈100% flux recovery and nearly zero irreversible oil fouling. This study provides a new strategy for designing anti‐oil‐fouling membranes toward practical oil/water separation applications.