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Microalgae are new and sustainable sources of starch with higher productivity and flexible production modes than conventional terrestrial crops, but the downstream processes need further development. Here, ultrasonication (with power of 200 W or 300 W and duration of 10, 15, 20, or 25 min) was applied to simultaneously extract and modify starch from a marine microalga Tetraselmis subcordiformis for reducing the digestibility, and an aqueous two-phase system (ATPS) of ethanol/NaH2PO4 was then used to isolate the starches with varied properties. Increasing ultrasonic duration facilitated the partition of starch into the bottom pellet, while enhancing the ultrasonic power was conducive to the allocation in the interphase of the ATPS. The overall starch recovery yield reached 73 ∼ 87 % and showed no significant difference among the ultrasonic conditions tested. The sequential ultrasonication-ATPS process successfully enriched the starch with purities up to 65 % ∼ 88 %, which was among the top levels reported in microalgal starch isolated. Ultrasonication produced more amylose which was mainly fractionated into the interface of the ATPS. The digestibility of the starch was altered under different ultrasonic conditions and varied from different ATPS phases as well, with the one under the ultrasonic power of 200 W for 15 min at the bottom pellet having the highest resistant starch content (RS, 39.7 %). The structural and compositional analysis evidenced that the ultrasonication-ATPS process could exert impacts on the digestibility through altering the surface roughness and fissures of the starch granules, modulating the impurity compositions (protein and lipid) that could interact with starch, and modifying the long- and short-range ordered structures. The developed ultrasonication-ATPS process provided novel insights into the mechanism and strategy for efficient production of functional starch from microalgae with a potential in industrial application.

Rehabilitation robots play an increasingly important role in the recovery of motor function for stroke. To ensure a natural physical human-robot interaction (pHRI) and enhance the active participation of subjects, it is necessary for the robots to understand the human intention and cooperate actively with humanlike characteristics. This study proposed a hybrid active control algorithm with human motion intention detection. The motion intention was defined as the desired position and velocity, which were continuously estimated according to the human upper-limb model and minimum jerk model, respectively. The motion intention was then fed into a hybrid force and position controller of an upper-limb cable driven rehabilitation robot (CDRR). And a three-dimensional reaching task without predefined trajectory was employed to validate the effectiveness of the proposed control algorithm. Experimental results showed that the control algorithm could continuously recognize the human motion intention and enabled the robot better movement performance indicated as smaller offset error, smoother trajectory, and lower impact. The proposed method could guarantee a natural pHRI and improve the engagement of the subjects, which has great potential in clinical applications.

Chrysolaminarin, a kind of water-soluble bioactive β-glucan produced by certain microalgae, is a potential candidate for food/pharmaceutical applications. This study identified a marine microalga Isochrysis zhangjiangensis, in which chrysolaminarin production was investigated via nutrient (nitrogen, phosphorus, or sulfur) deprivations (-N, -P, or -S conditions) along with an increase in light intensity. A characterization of the antioxidant activities of the chrysolaminarin produced under each condition was also conducted. The results showed that nutrient deprivation caused a significant increase in chrysolaminarin accumulation, though this was accompanied by diminished biomass production and photosynthetic activity. -S was the best strategy to induce chrysolaminarin accumulation. An increase in light intensity from 80 (LL) to 150 (HL) µE·m−2·s−1 further enhanced chrysolaminarin production. Compared with -N, -S caused more suitable stress and reduced carbon allocation toward neutral lipid production, which enabled a higher chrysolaminarin accumulation capacity. The highest chrysolaminarin content and concentration reached 41.7% of dry weight (%DW) and 632.2 mg/L, respectively, under HL-S, with a corresponding productivity of 155.1 mg/L/day achieved, which exceeds most of the photoautotrophic microalgae previously reported. The chrysolaminarin produced under HL-N (Iz-N) had a relatively competitive hydroxyl radical scavenging activity at low concentrations, while the chrysolaminarin produced under HL-S (Iz-S) exhibited an overall better activity, comparable to the commercial yeast β-glucan, demonstrating I. zhangjiangensis as a promising bioactive chrysolaminarin producer from CO2.

Green construction engineering is closely related to people's production and life, and its quality will directly affect people's lives and property. The rapid development of the economy has caused tremendous damage to the environment and energy. The concept of green environmental protection has been highly valued by all sectors of society. In order to improve the quality of green building projects, it is necessary to analyze the human factors, material quality factors, mechanical equipment factors and environmental safety factors that affect the quality of the project, and find out the problems and take measures to improve the management system. The green construction management mode is to introduce the concept of green environmental protection based on the traditional management mode, and it is more suitable for the development strategy of energy conservation and emission reduction. The article analyzes the problems existing in green construction management of China's green building construction projects, and puts forward countermeasures for developing green construction management. [ABSTRACT FROM AUTHOR]

Modeling land-use change is a prerequisite to understanding the complexity of land-use- change patterns. This paper presents a novel method to model urban land-use change using support-vector machines (SVMs), a new generation of machine learning algorithms used in classification and regression domains. An SVM modeling framework has been developed to analyze land-use change in relation to various factors such as population, distance to roads and facilities, and surrounding land use. As land-use data are generally unbalanced, in the sense that the unchanged data overwhelm the changed data, traditional methods are incapable of classifying relatively minor land-use changes with high accuracy. To circumvent this problem, an unbalanced SVM has been adopted by enhancing the standard SVMs. A case study of Calgary land-use change demonstrates that the unbalanced SVMs can achieve high and reliable performance for land-use-change modeling. [ABSTRACT FROM AUTHOR]

In recent years, there has been a significant shift in the development of a Geographic Information System (GIS) from desktop applications to mobile field applications. By integrating the precision location data collection capability of Global Positioning System (GPS) and the spatial processing power of GIS, mobile GIS provides an ideal basis of building systems for field workers to collect data with increased efficiency and ease. This paper presents the design and implementation of a pavement distress data collection and management system for efficient airport pavement condition inspection with the aid of mobile GIS. The system seeks to streamline the field data collection process by offering a customized user interface for distress data entry, transformation, retrieval, and real-time transmission through wireless handheld devices. An R*-tree algorithm has been explored to index the distress data and speed up the retrieval of distress information when performing spatial and attribute searches. A least squares adjustment algorithm is also introduced in an effort to improve the precision of GPS data. Furthermore, a wireless communication algorithm has been developed to enable the transmission of distress data from the mobile client in the field to the in-house GIS server. On the side of hardware, Pocket PC has been chosen as the platform for deploying all field operations. Three peripheral devices, namely the GPS receiver, digital camera and wireless card, are attached to the Pocket PC for capturing distress location, digital photos and support wireless communication, respectively. The effectiveness and efficiency of the system have been tested and verified by various field trials in Singapore Changi International Airport. [ABSTRACT FROM AUTHOR]

The research introduced selection and breeding process, characteristics and high-yield cultivation technology of Wuqing No.1. Wuqing No.1, also named Gaoyou black soybean, is bred based on Danbo black soybean introduced from Japan in 1996 by Gaoyou Vegetable Cultivation Technology Station and Yangzhou Agricultural Technology Promotion Station. It was named in 2014 by Jinagsu Crop Cultivar Approvement Committee. The cultivar is high-yielding with high quality, big seeds, high resistance to stress, as well as high health-care value. [ABSTRACT FROM AUTHOR]