High-quality ice plant reference genome analysis provides insights into genome evolution and allows exploration of genes involved in the transition from C3 to CAM pathways.

Ice plant (Mesembryanthemum crystallinum), a member of the Aizoaceae family, is a typical halophyte crop and a model plant for studying the mechanism of transition from C3 photosynthesis to crassulacean acid metabolism (CAM). Here, we report a high-quality chromosome-level ice plant genome sequence. This 98.05% genome sequence is anchored to nine chromosomes, with a total length of 377.97 Mb and an N50 scaffold of 40.45 Mb. Almost half of the genome (48.04%) is composed of repetitive sequences, and 24 234 genes have been annotated. Subsequent to the ancient whole-genome triplication (WGT) that occurred in eudicots, there has been no recent whole-genome duplication (WGD) or WGT in ice plants. However, we detected a novel WGT event that occurred in the same order in Simmondsia chinensis, which was previously overlooked. Our findings revealed that ice plants have undergone chromosome rearrangements and gene removal during evolution. Combined with transcriptome and comparative genomic data and expression verification, we identified several key genes involved in the CAM pathway and constructed a comprehensive network. As the first genome of the Aizoaceae family to be released, this report will provide a rich data resource for comparative and functional genomic studies of Aizoaceae, especially for studies on salt tolerance and C3-to-CAM transitions to improve crop yield and resistance.

Preliminary Study of Pulsed Ultraviolet Technology for Low-Temperature Disinfection.

Introduction: To explore the feasibility of pulsed ultraviolet (UV) light technology for low-temperature disinfection, a series of experiments were conducted. Methods: Pulsed UV technology's effectiveness in disinfecting Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli on different carriers were studied under varying temperatures. Results: Under different temperatures and constant radiation illumination (i.e., distance), the disinfection effect was correlated with irradiation time; among the three carriers, the disinfection effect of cloth sheets was the best, followed by stainless steel sheets, and corrugated paper sheet. The disinfection effect on Gram-negative bacteria Escherichia coli was better than that on Gram-positive bacteria Staphylococcus aureus overall. Discussion: Temperature has a limited effect on pulsed UV disinfection. Irradiation times and carrier types are influencing factors.

Self-adjusted decomposition for multi-model predictive control of Hammerstein systems based on included angle.

A self-adjusted multi-model decomposition (SAMMD) method is proposed based on included angle (IA) to realize multi-model predictive control (MMPC) of Hammerstein systems. Given an initial value for threshold and a step-size, a balanced decomposition in terms of Measurement of Nonlinearity (MoN) is obtained with an appropriate linear model set to approximate the considered Hammerstein system. Based on the linear model set, a MMPC is designed for set-point tracking and anti-disturbance control using an offline weighting method. Thus, time-consuming tuning of threshold value is largely avoided; reliance on experience is greatly decreased. And the efficiency and quality of decomposition are largely raised. A CSTR process and a Lab-tank system that can be approximated by Hammerstein models are investigated. Simulations illustrate that the proposed SAMMD method is both effective and efficient.

Reaction kinetics of phenols and p-nitrophenols in flowing aerated aqueous solutions generated by a discharge plasma jet.

In this paper, we propose a method for removing phenols and p-nitrophenols (PNPs) from flowing aqueous solutions generated by atmospheric pressure plasma jets (APPJs). For analyzing the removal characteristics, multiple techniques were used, including flow speed analysis of the aerated solution, optical emission spectroscopy (OES), and liquid chromatography. In addition, the reaction kinetics of diffusion and activation control processes were evaluated using aerated fluid speed variation and the corresponding activation energy. From these results, the relative intensities of hydroxyl radicals produced by an APPJ in water were found to be stronger than those in air and to decrease with increasing flow speed. Furthermore, the reaction kinetics were found to be diffusion-controlled when the solution flow speed was low and activation-controlled under high solution flow speed. It was also found that the degradation efficiency was enhanced with increasing flow speed, which increased the discharge voltage and temperature of the solution and changed the initial pH value when TiO2/UV catalysis was used. From the complex relationship between the reactive species, fluid diffusion, and discharge parameters in wastewater described herein, it is anticipated that these findings will facilitate new approaches to both the design and optimization of discharge reactors intended for wastewater treatment.

Propagation characteristics of interface waves between a porous medium and a sediment-containing two-phase fluid.

Based on the modified Biot theory of Johnson, the propagation characteristics of the various interface waves at an interface between a semi-infinite fluid and a porous medium were studied. First, based on the characteristic equations of open-pore and sealed-pore, which were derived from the wave equations, time-domain waveforms at the interface were obtained by inverse Fourier transform. The effects of the longitudinal frame modulus on the interface waves were investigated. For open-pore and sealed-pore, the effect of porosity on the propagation of the interface waves was studied; the porosity was found to strongly influence the true surface wave. Based on four ultrasonic suspension models-Utrick, Utrick-Ament (UA), Harker-Temple (HT) and McClement, the pseudo-Stoneley wave propagation characteristics were analyzed at the interface between the sediment-containing two-phase fluid and the porous medium solid. The effects of volume fraction and particle diameter on the phase velocity, attenuation coefficient and dispersion for the pseudo-Stoneley and true surface wave were discussed, and the results demonstrated that the properties of the fluid strongly impacted the pseudo-Stoneley wave but exerted very little effect on the true surface wave. The conclusions drawn in this paper could contribute to elucidate the parameters of sediment and porous media.

Syntheses of silsesquioxane (POSS)-based inorganic/organic hybrid and the application in reinforcement for an epoxy resin.

A new inorganic/organic hybrid material containing silsesquioxane was prepared by the reaction of caged octa (aminopropyl silsesquioxane) (POSS-NH(2)) with n-butyl glycidyl ether (nBGE) and 1,4-butanediol diglycidyl ether (BDGE). The copolymers of POSS, nBGE, and BDGE could be obtained with varied feed ratio of POSS-NH(2), nBGE, and BDGE in the preparation. The hybrid material was added into an epoxy resin (E51) for enhancing the toughening and thermal properties of the epoxy resin. The results showed that the toughening and the thermal properties of the cured epoxy resin were greatly improved by the addition of the hybrid. The enhancement was ascribed to nano-scale effect of the POSS structure and the formation of anchor structure in the cured network. The investigation of kinetics for the curing process of the hybrid-modified epoxy resin revealed that two kinds of curing reactions occurred in different temperature ranges. They were attributed to the reactions between amino groups of the curing agent with epoxy groups of E51 and with residue epoxy groups in the hybrid. The reacting activation energies were calculated based on Kissinger's and Flynn-Wall-Ozawa's methods, respectively.

Hydrophobic modification of sodium alginate and its application in drug controlled release.

Sodium alginate was hydrophobically modified by coupling of polybutyl methacrylate onto the alginate. The polybutyl methacrylate was previously prepared through polymerization of butyl methacrylate in the presence of 2-amino-ethanethiol as a chain transfer agent. The structure of the product was characterized by Fourier-transformed infrared spectrometry, nuclear magnetic resonance ((1)HNMR) and thermogravimetry. The result of fluorescence analysis showed that the hydrophobicity of the modified alginate was obviously increased. The modified alginate conjugate was used for immobilization of bovine serum albumin in the presence of calcium chloride. In addition, the release behavior of the drug-loaded alginate in deionized water and Tris-HCl buffer solution (pH 7.2) was investigated. It was found that the modified sodium alginate possessed prolonged release behavior compared to unmodified sodium alginate, and it had potential application in controlled release as a drug carrier.

Study of a peak in cavitation activity from HIFU exposures using TA fluorescence.

Methods of measuring the sound field and focal region of a 1.05 MHz high intensity focused ultrasound (HIFU) are described in this paper. 1.05 MHz pulsed HIFU with intensity 2400 W/cm(2) with a 1:1 duty cycle ("on" phase equaled "off" phase) was used to irradiate terephthalic acid (TA). Pulse periods of 0.5 ms, 1 ms, 3.3 ms, 10 ms, 15 ms, 33 ms, 0.1s and 1s were used. The irradiation time was 2 min. To indicate the intensity of inertial cavitation activity, the fluorescence intensity of hydroxyterephthalic acid (HTA) was measured. The result shows that the cavitation activity of pulsed HIFU peaks at a pulse period of 10 ms, cavitation activity is significantly greater for pulse periods from 2 to 20 ms than for others.

Enhancement of ultrasonic cavitation yield by multi-frequency sonication.

The paper reports the enhanced effect of multi-frequency ultrasonic irradiation on cavitation yield. The cavitation yield is characterized by electrical conductivity determination, fluorescence intensity determination and iodine release method. Two-frequency (28 kHz/0.87 MHz) orthogonal continuous ultrasound, two-frequency (28 kHz/0.87 MHz) orthogonal pulse ultrasound and three-frequency (28 kHz/1.0 MHz/1.87 MHz) orthogonal continuous ultrasound have been used. It has been found that the combined irradiation of two or more frequencies of ultrasound can produce a significant increase in cavitation yield compared with single frequency irradiation. The possible mechanisms of the enhanced effect are briefly discussed.

Fluorescence enhancement of the aqueous solution of terephthalate ion after bi-frequency sonication.

The fluorescence enhancement of the aqueous solution of terephthalate ion (TA) under orthogonal sonication of 28 kHz and 1.7 MHz ultrasonic wave has been studied. It has been found that the fluorescence intensity of TA solution after bi-frequency ultrasonic irradiation is obviously higher than the sum of those under two individual ultrasonic irradiations.