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The coexistence of anions and cations in zwitterionic hydrogels results in electrostatic interactions between the polymer chains. This structure endows zwitterionic hydrogels with higher ion sensitivity and promising properties, such as anti-polyelectrolyte and thermosensitive effects. Hydrophilic groups on the molecular backbone give zwitterionic hydrogels good biocompatibility, and they effectively resist the non-specific adsorption of proteins. The abundant functional groups on the molecular skeleton also facilitate the chemical modification of zwitterionic hydrogels. In recent years, these excellent properties have made zwitterionic hydrogels broadly interesting and they have been heavily studied for medical applications. A comprehensive review will help researchers have a deeper understanding of zwitterionic hydrogels and their potential applications. In this review, the types, functional characteristics, and applications in the biomedicine of zwitterionic hydrogels are summarized in detail. In addition, the challenges and opportunities for using zwitterionic hydrogels for biomedical applications are discussed.

This book presents the fundamental theories, methodologies and case studies of marine ecosystem modeling with a special focus on marine ecological dynamics that could provide scientists and researchers with a stabile and reliabile technical framework to study marine life and their developments.This book also clarifies the research objective and model classification methods of marine ecosystem dynamics research and analyzes the key marine ecological processes that affect modeling. The technical framework for improving the performance of modeling is also proposed, and the latest progress in research, as well as existing difficulties and challenges in end-to-end dynamics models are reviewed and analyzed. A dimensionality reduction theorem is established and derived for analyzing the stability of the solutions of a class of self-conserving marine ecosystem dynamic models. Also included in this work are several new types of marine ecosystem dynamics models constructed by modern computing methods — including artificial neural networks, cellular automata, and statistical dynamics — and case studies.This book is a suitable reference for professional and technical personnel, managers and graduate students specializing in the evolution mechanism, simulation, predication and regulation of marine ecosystems.

Membrane fouling still remains the main limitation for the development of membrane bioreactor (MBR). In this thesis, the main objective focuses on the effects of pharmaceutical micropollutants which are frequently found in domestic wastewater on MBR fouling. Carbamazepine (CBZ), an anti-epileptic drug, was chosen in this study due to its occurrence in domestic wastewater and persistency in MBR process. The effects of CBZ on MBR fouling were investigated in two different ways of contact, i.e. short-term peak contact and long-term continuous contact. The results showed that during only 3 hours contact with 100 μg L-1 CBZ, the fouling propensity of the sludge increased due to the increase in 100-1000 kDa protein-like substances in the supernatant, which could be completely retained by the MBR membrane and the membranes used in the filterability tests. The increase of 100-1000 kDa protein-like compounds in the supernatant may probably be caused by the bacterial decay when facing the pharmaceutical stress. Besides, the reduced effect was observed for sludge obtained from MBR operated under higher organic loading rate. During the long-term continuous contact, significantly higher MBR fouling rate was observed after the continuous addition of CBZ in the MBR via the feed (90 μg L-1 CBZ in the feed), which could be related to the significant increase of 10-100 kDa protein-like compounds in the supernatant after addition of CBZ. The 10-100 kDa protein-like compounds could accumulate in the biocake, which was formed on MBR membrane surface, modify the biocake structure and change the retention characteristics of MBR. The increase of 10-100 kDa protein-like compounds was probably caused by the defensive response of bacteria when continuously facing the pharmaceutical stress. Slight inhibition of microbial activity was found several days after addition of CBZ in MBR, and then it was stabilized to some constant level due to the acclimation of sludge to the pharmaceutical stress. Similar, significant increase of protein concentration was observed at the beginning several days after addition of CBZ in MBR, then returned to the initial level. No significant change in sludge floc size and polysaccharide concentration in supernatant was found during the long-term continuous contact period. This study could help to enhance the understanding of complex interactions among pharmaceutical micropollutants, activated sludge and MBR fouling.