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Studies have shown that applying a reflective film to the floor of an orchard enhances fruit colouration. Here we assessed whether this practice also prolonged the post-harvest storage life of apple (Malus x domestica Borkh cv. Fuji and Malus prunifolia [Willd.]) fruit. Strips of reflective mulching film (RMF) were placed beneath the apple trees and RMF-treated fruit were compared with those from untreated control (CK) trees. Enzymes involved in reducing lipid peroxidation such as superoxide dismutase (SOD) and catalase (CAT) are associated with delaying fruit senescence. Their activities, as well as malondialdehyde (MDA) concentrations, were quantified as indicators of physiological changes related to lipid peroxidation and membrane damage in the peel and flesh of RMF-treated or control apple fruit during 50 d of post-harvest storage at 4°C. SOD activities increased in the peel and flesh from RMF-treated fruit during the first 40 d post-harvest, but declined significantly during the final 10 d of storage. RMF treatment resulted in increases in CAT activities of 5 - 14% and 16 - 29% in the peel and flesh of RMF-treated apples, respectively, compared with untreated CK fruit. Conversely, MDA concentrations were 7 - 23% and 14 - 30% lower in the peel and flesh, respectively, of RMF-treated fruit than in CK fruit over the 50 d storage period. Similarly, RMF treatment resulted in reductions of 7 - 20% and 3 - 10% in saturated fatty acid (SFA) concentrations in the peel and flesh, respectively, compared to CK fruit, while the corresponding polyunsaturated fatty acid (PUFA) concentrations increased by 2 - 10% and 3 - 7%. In conclusion, the use of RMF in apple orchards appears to be an effective technique to delay post-harvest senescence in apple fruit. [ABSTRACT FROM AUTHOR]

We investigate the index tracking model with the analysis and optimization of tracking dynamic properties. The return deviations between tracking portfolio and the index are first decomposed into several components with different time-scale features. Our model then filters out components at low frequencies. Our approach is implemented to five data sets drawn from major world markets. The results show that our method could control the tracking dynamics and such control could also improve the terminal performance of index tracking. [ABSTRACT FROM PUBLISHER]

A new type of rat-race coupler, based on electromagnetic bandgap (EBG)-loaded half-mode substrate integrated waveguide (HMSIW) and composite right/left-handed (CRLH) HMSIW, has been proposed and investigated comprehensively. It consists of three sections of EBG-loaded HMSIWs with 90° phase delay and one section of CRLH HMSIW with −90° phase advance. Due to the evanescent-mode of EBG-loaded HMSIW and the backward behavior of the CRLH HMSIW in the left-handed region, the size of such a miniaturized rat-race coupler is reduced about 65.7% in comparison with its conventional counterpart. The rat-race coupler with the central frequency of 5.5 GHz has been designed and fabricated so as to validate our method, and its good performance is demonstrated by both simulated and measured results. [ABSTRACT FROM AUTHOR]

In this article, modelling and robust stability of networked control systems (NCS) are discussed. Considering the existence of packet reordering and network-induced delay, a new mathematical model of NCS whose network-induced delay is longer than one sampling period is obtained, which can fully describe packet reordering and effectively eliminate the impact of packet reordering on the performance of NCS such that the newest control input can be executed by the actuator. Based on this model, the time-varying NCS is converted into an uncertain discrete linear system with multi-step delay in terms of matrix theory. Furthermore, a sufficient condition for robust stability of NCS is presented. Linear matrix inequality approach has been employed to solve the controller design problems. Numerical examples are compared with previous schemes to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper presents the design of one dimensional broadband phase shifters based on a new class of negative refraction index transmission line. The proposed phase shifter here consists of conventional microstrip line and Negative Refraction Index (NRI) transmission line (TL) in which ideal operational amplifiers are applied to form the periodically loaded negative-impedance-converted inductors and capacitors. It is demonstrated that variations in inductors and capacitors can produce arbitrary phase shifts while maintaining the same overall length. Also, the NRI-TL is non-dispersive so that the new phase shifter can be used in many new broadband devices. [ABSTRACT FROM AUTHOR]

An approach to realize left-handedness in microstrip transmission line by simultaneously loading it with split ring resonator and complementary split ring resonator is proposed. A transmission line individually loaded with either with SRR (-μ) or CSRR (-ε) has band rejection but when simultaneously loaded has a passband near the previously rejected band due to negative values of both -μ and -ε. i.e., left handedness. The design is compact, low profile and independent of the substrate permittivity. Simulation and experimental results are also presented and the design is suitable for devices like filters and couplers. [ABSTRACT FROM AUTHOR]

Square-planar nickel(II) complex with tridentate ONO-donor 4-[(2-hydroxyphenyl)imino]-2-pentanone (H2hpac) and imidazole (Himdz) are reported. The complex was synthesized in moderate yield by reacting Ni(O2CCH3)2 · 4H2O, H2hpac and imidazole in 1 : 1 : 1 mole ratio and characterized by elemental analysis, IR, 1H NMR spectroscopy. An X-ray structure determination of the complex has been completed. In the solid state, a one-dimensional assembly of the [Ni(hpac)(Himdz)] molecules is formed via intermolecular hydrogen bonds between the imidazole N-H groups and the coordinated hydroxyphenyl-O atoms. [ABSTRACT FROM AUTHOR]