The Natural Ecology and Stock Enhancement of the Edible Jellyfish (Rhopilema esculentum Kishinouye, 1891) in the Liaodong Bay, Bohai Sea, China

Among the edible jellyfish species, Rhopilema esculentum Kishinouye, 1891, is one of the most abundant jellyfish species consumed. Therefore, this jellyfish species is an important fisheries source in China. The jellyfish fisheries in China show annually considerable fluctuations and have a very short season. In the chapter, we firstly try to review the natural ecology of R. esculentum, which includes the distribution and migration, growth model, and survival rate in the Liaodong Bay (LDB) based on the results of our field studies for more than 20 years. Secondly, we focus on reviewing the jellyfish fishery and population dynamic in the LDB. Thirdly, we emphasize the themes, including the survey methods, catch prediction, enhancement assessment, and fishery management, based on our survey results from 2005 to 2010. Finally, we present our field and experiment results of resource restoration. The high commercial value of R. esculentum enhancement in the LDB has made this a very successful enterprise

Sparse online collaborative filtering with dynamic regularization

Abstract(#br)Collaborative filtering (CF) approaches are widely applied in recommender systems. Traditional CF approaches have high costs to train the models and cannot capture changes in user interests and item popularity. Most CF approaches assume that user interests remain unchanged throughout the whole process. However, user preferences are always evolving and the popularity of items is always changing. Additionally, in a sparse matrix, the amount of known rating data is very small. In this paper, we propose a method of online collaborative filtering with dynamic regularization (OCF-DR), that considers dynamic information and uses the neighborhood factor to track the dynamic change in online collaborative filtering (OCF). The results from experiments on the MovieLens100K, MovieLens1M, and HetRec2011 datasets show that the proposed methods are significant improvements over several baseline approaches

Characterization of large tilt-angle flexoelectro-optic switching in chiral nematic liquid crystal devices

The “flexoelastic ratio”, which is the ratio of the effective flexoelectric coefficient to the elasticcoefficients, is commonly used to characterize the electro-optic behavior of chiral nematic liquid crystal(LC) devices that exhibit flexoelectro-optic switching. In the uniform lying helix configuration, thiselectro-optic effect is manifested as a rapid (~100 s) rotation of the macroscopic optic axis when anelectric field is applied perpendicular to the helix axis of the chiral nematic LC and is attractive for bothintensity and phase modulation devices. There has been renewed interest in this electro-effect as newLC materials and mixtures have been developed that exhibit large tilt angles, , of the optic axis ( ≥45°) whilst maintaining a fast response time. In this Letter, we consider the relevance of the flexoelasticratio when characterizing the performance of the devices and find that an alternative ratio is required tocharacterize materials that can switch by = ±45° when the pitch is constrained. We show that for largetilt angles of the optic axis the values for the new and conventional flexoelastic ratios measurablydiverge. In addition, a simple way of determining this new characteristic ratio is presented that involvesdetermining the electric field amplitude at the point the transmission levels are the same for bothpositive and negative electric field polarities

From Selection to Instruction and Back: Competing Conformational Selection and Induced Fit Pathways in Abiotic Hosts

Two limiting cases of molecular recognition, induced fit (IF) and conformational selection (CS), play a central role in allosteric regulation of natural systems. The IF paradigm states that a substrate “instructs” the host to change its shape after complexation, while CS asserts that a guest “selects” the optimal fit from an ensemble of preexisting host conformations. With no studies that quantitatively address the interplay of two limiting pathways in abiotic systems, we herein and for the first time describe the way by which twisted capsule M-1, encompassing two conformers M-1(+) and M-1(−), trap CX4 (X=Cl, Br) to give CX4⊂M-1(+) and CX4⊂M-1(−), with all four states being in thermal equilibrium. With the assistance of 2D EXSY, we found that CBr4 would, at its lower concentrations, bind M-1 via a M-1(+)→M-1(−)→CBr4⊂M-1(−) pathway corresponding to conformational selection. For M-1 complexing CCl4 though, data from 2D EXSY measurements and 1D NMR line-shape analysis suggested that lower CCl4 concentrations would favor CS while the IF pathway prevailed at higher proportions of the guest. Since CS and IF are not mutually exclusive, we reason that our work sets the stage for characterizing the dynamics of a wide range of already existing hosts to broaden our fundamental understanding of their action. The objective is to master the way in which encapsulation takes place for designing novel and allosteric sequestering agents, catalysts and chemosensors akin to those found in nature

Fast and low loss flexoelectro-optic liquid crystal phase modulator with a chiral nematic reflector.

In this paper, we demonstrate a flexoelectro-optic liquid crystal phase-only device that uses a chiral nematic reflector to achieve full 2π phase modulation. This configuration is found to be very tolerant to imperfections in the chiral nematic reflector provided that the flexoelectro-optic LC layer fulfils the half-wave condition. Encouragingly, the modulation in the phase, which operates at kHz frame rates, is also accompanied by low amplitude modulation. The configuration demonstrated herein is particularly promising for the development of next-generation liquid crystal on silicon spatial light modulators

Flexoelectro-optic liquid crystal analog phase-only modulator with a 2π range and 1 kHz switching

We present a flexoelectro-optic liquid crystal (LC) analog phase modulator with >

Closed Aromatic Tubes-Capsularenes

In this study, we describe a synthetic method for incorporating arenes into closed tubes that we name capsularenes. First, we prepared vase-shaped molecular baskets 4–7. The baskets comprise a benzene base fused to three bicycle[2.2.1]heptane rings that extend into phthalimide (4), naphthalimide (6), and anthraceneimide sides (7), each carrying a dimethoxyethane acetal group. In the presence of catalytic trifluoroacetic acid (TFA), the acetals at top of 4, 6 and 7 change into aliphatic aldehydes followed by their intramolecular cyclization into 1,3,5-trioxane (1H NMR spectroscopy). Such ring closure is nearly a quantitative process that furnishes differently sized capsularenes 1 (0.7×0.9 nm), 8 (0.7×1.1 nm;) and 9 (0.7×1.4 nm;) characterized by X-Ray crystallography, microcrystal electron diffraction, UV/Vis, fluorescence, cyclic voltammetry, and thermogravimetry. With exceptional rigidity, unique topology, great thermal stability, and perhaps tuneable optoelectronic characteristics, capsularenes hold promise for the construction of novel organic electronic devices

Dynamic and Assembly Characteristics of Deep-Cavity Basket Acting as a Host for Inclusion Complexation of Mitoxantrone in Biotic and Abiotic Systems

We describe the preparation, dynamic, assembly characteristics of vase-shaped basket 13− along with its ability to form an inclusion complex with anticancer drug mitoxantrone in abiotic and biotic systems. This novel cavitand has a deep nonpolar pocket consisting of three naphthalimide sides fused to a bicyclic platform at the bottom while carrying polar glycines at the top. The results of 1H Nuclear Magnetic Resonance (NMR), 1H NMR Chemical Exchange Saturation Transfer (CEST), Calorimetry, Hybrid Replica Exchange Molecular Dynamics (REMD), and Microcrystal Electron Diffraction (MicroED) measurements are in line with 1 forming dimer [12]6−, to be in equilibrium with monomers 1(R)3− (relaxed) and 1(S)3− (squeezed). Through simultaneous line-shape analysis of 1H NMR data, kinetic and thermodynamic parameters characterizing these equilibria were quantified. Basket 1(R)3− includes anticancer drug mitoxantrone (MTO2+) in its pocket to give stable binary complex [MTO⊂1]− (Kd=2.1 μM) that can be precipitated in vitro with UV light or pH as stimuli. Both in vitro and in vivo studies showed that the basket is nontoxic, while at a higher proportion with respect to MTO it reduced its cytotoxicity in vitro. With well-characterized internal dynamics and dimerization, the ability to include mitoxantrone, and biocompatibility, the stage is set to develop sequestering agents from deep-cavity baskets

Fast and low loss flexoelectro-optic liquid crystal phase modulator with a chiral nematic reflector

© 2019, The Author(s). In this paper, we demonstrate a flexoelectro-optic liquid crystal phase-only device that uses a chiral nematic reflector to achieve full 2π phase modulation. This configuration is found to be very tolerant to imperfections in the chiral nematic reflector provided that the flexoelectro-optic LC layer fulfils the half-wave condition. Encouragingly, the modulation in the phase, which operates at kHz frame rates, is also accompanied by low amplitude modulation. The configuration demonstrated herein is particularly promising for the development of next-generation liquid crystal on silicon spatial light modulators

Fast and low loss flexoelectro-optic liquid crystal phase modulator with a chiral nematic reflector

© 2019, The Author(s). In this paper, we demonstrate a flexoelectro-optic liquid crystal phase-only device that uses a chiral nematic reflector to achieve full 2π phase modulation. This configuration is found to be very tolerant to imperfections in the chiral nematic reflector provided that the flexoelectro-optic LC layer fulfils the half-wave condition. Encouragingly, the modulation in the phase, which operates at kHz frame rates, is also accompanied by low amplitude modulation. The configuration demonstrated herein is particularly promising for the development of next-generation liquid crystal on silicon spatial light modulators