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This study presents an alternative method for solving a general class of control synthesis problems by employing chain-scattering matrix descriptions and coprime factorisations. Extended from Kimura's approach, the proposed method follows an abridged development without the need for any plant augmentation or the conjugation technique in its solution process. It is shown that general control synthesis problems, including those for stabilising controllers or further for H 2 controllers, can be represented via two associated chain-scattering matrix descriptions and solved by means of two coprime factorisations. In the two-port chain description framework, the coprime factorisation is utilised as the fundamental idea instead of J-spectrum factorisation from the perspective of facilitating the process of guaranteeing no unstable pole-zero cancellation. A significant contribution of this study is its transparency and intuitive nature, providing a systematic theory of control and allowing practicing control engineers to learn this approach more easily and apply it to advanced control systems. Related graphic network representations are also presented to help explain the whole concept which will benefit engineering readers.

Green-lipped mussels Perna viridis secrete a larger number of byssus threads to anchor themselves to the substrate more firmly when predation risks are high. These mussels also form clumps. As predators usually attack clumps from the periphery, the predation risks of solitary mussels are higher than those of mussels living along the edge of clumps, which are in turn higher than those of mussels living within the clumps. The byssus thread number, length and diameter were investigated in relation to the mussels’ position in the clump. We set up chemical stimulus treatments with damaged conspecifics and heterospecifics, suggesting predation risks, as well as with intact conspecifics and heterospecifics, shrimp cues and control (no cue). The mean number of byssus threads produced was significantly affected by both the mussels’ position in the clump, the treatment type, and the interactive effect between these 2 variables. In the treatment in which mussels were exposed to damaged conspecific cues, the mean number of byssus threads produced by the solitary mussels was greater than the number produced by edge mussels, which was, in turn, greater than the number produced by the mussels within the clump. Furthermore, the solitary and edge mussels exposed to damaged conspecifics secreted more byssus threads than their counterparts in the control, intact conspecifics, intact and damaged heterospecifics, and shrimp meat treatments. However, the mussels within the clumps exposed to damaged conspecifics did not secrete more byssus threads than their control counterparts. Results of the present study suggest that the anti-predator responses to risk may be related to the presence of damaged conspecifics and the mussels’ position in the clump, both indicative of local predation pressure.

A single factorial experiment was conducted to test the effects of three dietary levels of energy on mRNA expression of fatty acid synthase (FAS-mRNA) and hormone-sensitive lipase (HSL-mRNA) and their association with intramuscular fat in finishing pigs. 72 crossbred (Large WhitexRongchang) barrows with an average initial body weight of 20.71 (s.e. 0.1) kg, were randomly allotted to three dietary treatments (11.75, 13.05 and 14.36 MJ DE/kg) and fed until slaughtered at 100 or 101 kg. The diets were iso-nitrogenous and iso-essential amino acids. The growth performances including the duration of finishing were changed linearly (p

The objective of this study was to compare coronary artery bypass graft (CABG) surgery with non-extracorporeal vs. extracorporeal circulation. The study outcomes included operative time, number of graft vessels, pulmonary infection rates, and systemic inflammatory markers.96 patients received selective CABG, either with non-extracorporeal (study group; n = 48) or extracorporeal circulation (control group; n = 48). Operative time, pulmonary infection rates, and blood levels of inflammatory markers TNF-α, IL-6, and IL-8 before and 4, 24, and 48 hours after the surgery were quantified. Graft vessels were quantified using computed tomography.Operative time was significantly shorter in study group (4.58 ± 0.91 vs. 5.36 ± 1.12 hours in control group; p0.05). The number of graft vessels and pulmonary infection rates were comparable between both techniques. However, systemic inflammatory markers were significantly (p0.05) lower in study group at 4 and, partly, 24 hours after the surgery.Extracorporeal circulation prolongs operation and can aggravate systemic inflammatory response. Therefore, CABG with non-extracorporeal circulation offers more beneficial outcomes.

Macrophages from C57BL/6J mice, an animal susceptible to atherosclerosis, were chosen as target cells to study changes in the transmembrane Ca2+ gradient during the formation of macrophage-derived foam cells. The transmembrane Ca2+ gradients of single living cells were examined-using Fura-2/AM combined with Fluo-3/AM by laser scanning confocal microscopy. Exposure to Oxidized Low Density Lipoprotein, decreases the Ca2+ gradient across macrophage plasma membrane, but increases that across the nuclear membrane. The altered transmembrane Ca2+ gradients could induce the up-regulation of scavenger receptor in macrophages, resulting in the formation of foam cells.

The glucose transporter of human erythrocytes (Glut1) was reconstituted into soybean phospholipid liposomes by a method of direct incorporation using the nonionic detergent n-octyl beta-D-glucopyranoside. The reconstituted proteoliposomes were proved to be intact and low ionic permeability. Freeze-fracture electron microscopy study showed that the diameter of the proteoliposomes was about 150 +/- 50 nm and the protein was randomly distributed. The kinetic parameters of the reconstituted transporter were: Km =16.23 mmol/L, Vmax = 34.48 nmol/sec x mg protein. Furthermore, about 90% of the glucose transporter in the reconstituted proteoliposomes were orientated inside-out. Until now it is a more efficient method for uni-directional reconstitution of Glut1 with good reproducibility and higher transport activity.

The relationship between Ca2+ transport and energy transduction of myocardial mitochondria in the presence of reactive oxygen species was investigated. Following treatment with oxygen free radicals [superoxide(O2•) or hydroxyl radical (•)OH], lipid free radicals in myocardial mitochondrial membrane could be detected by using the method of EPR spin trap. Simultaneously there were obvious alterations in the free Ca2+ ([Ca2+]m) in the mitochondrial matrix; the physical state of membrane lipid; the efficiency of oxidative phosphorylation (ADP/O); the value of the respiratory control ratio (RCR); and the membrane potential of the inner membrane of myocardial mitochondria. If the concentrations of reactive oxygen species were reduced by about 30%, the alterations in the physical state of the membrane lipid and energy transduction of myocardial mitochondria were not observed, but the changes in Ca2+ homeostasis remained. We conclude that Ca2+ transport by myocardial mitochondria is more sensitive to agents such as (O2•) or •OH, etc. than are oxidation phosphorylation and the respiratory chain.

This review will focus on the recent advance in the study of effect of transmembrane Ca2+ gradient on the function of membrane proteins. It consits of two parts: 1. Transmembrane Ca2+ gradient and sarcoplasmic reticulum Ca2+-ATPase; 2. Effect of transmembrane Ca2+ gradient on the components and coupling of cAMP signal transduction pathway. The results obtained indicate that a proper transmembrane Ca2+ gradient may play an important role in modulating the conformation and activity of SR Ca2+-ATPase and the function of membrane proteins involved in the cAMP signal transduction by mediating the physical state change of the membrane phospholipids.

The conformational states of Ca2+-ATPase in sarcoplasmic reticulum (SR) vesicles with or without a thousand-fold transmembrane Ca2+ gradient have been studied by fluorescence spectroscopy and fluorescence quenching. In consequence of the establishment of the transmembrane Ca2+ gradient, the steady-state fluorescence results revealed a reproducible 8% decrease in the intrinsic fluorescence while time-resolved fluorescence measurements showed that 13 tryptophan residues in SR · Ca2+-ATPase could be divided into three groups. The fluorescence lifetime of one of these groups increased from 5.5 ns to 5.95 ns in the presence of a Ca2+ gradient. Using KI and hypocrellin B (a photosensitive pigment obtained from a parasitic fungus, growing in Yunnan, China), the fluorescence quenching further indicated that the dynamic change of this tryptophan group, located at the protein-lipid interface, is a characteristic of transmembrane Ca2+ gradient-mediated conformational changes in SR · Ca2+-ATPase.

Divalent cations play an important role in the functions of biomembranes. This review deals with three topics: (1) Mg2+-mediated change in physical state of phospholipid induces conformation and activity change of reconstituted mitochondrial H+-ATPase, (2) a proper transmembrane Ca2+ gradient is essential for the higher enzymatic activity of adenylate cyclase, and (3) role of transmembrane Ca2+ gradient in the modulation of reconstituted sarcoplasmic reticulm Ca2+-ATPase activity.

Using pulsed laser ablation with arsenic over pressure, the growth conditions for GaAs nanowires have been systematically investigated and optimized. Arsenic over pressure with As$_2$ molecules was introduced to the system by thermal decomposition of polycrystalline GaAs to control the stoichiometry and shape of the nanowires during growth. GaAs nanowires exhibit a variety of geometries under varying arsenic over pressure, which can be understood by different growth processes via vapor-liquid-solid mechanism. Single-crystal GaAs nanowires with uniform diameter, lengths over 20 $\mu$m, and thin surface oxide layer were obtained and can potentially be used for further electronic characterization.

Stimulation of the host immune system is crucial in cancer treatment. In particular, nonspecific immunotherapies, when combined with other traditional therapies such as radiation and chemotherapy, may induce immunity against primary and metastatic tumors. In this study, we demonstrate that a novel, non-toxic immunoadjuvant, glycated chitosan (GC), decreases the motility and invasion of mammalian breast cancer cells in vitro and in vivo. Lung metastatic ratios were reduced in 4T1 tumor-bearing mice when intratumoral GC injection was combined with local high-intensity focused ultrasound (HIFU) treatment. We postulate that this treatment modality stimulates the host immune system to combat cancer cells, as macrophage accumulation in tumor lesions was detected after GC-HIFU treatment. In addition, plasma collected from GC-HIFU-treated tumor-bearing mice exhibited tumor-specific cytotoxicity. We also investigated the effect of GC on epithelial-mesenchymal transition-related markers. Our results showed that GC decreased the expression of Twist-1 and Slug, proto-oncogenes commonly implicated in metastasis. Epithelial-cadherin, which is regulated by these genes, was also upregulated. Taken together, our current data suggest that GC alone can reduce cancer cell motility and invasion, whereas GC-HIFU treatment can induce immune responses to suppress tumor metastasis in vivo.

The role of a transmembrane Ca2+ gradient in anion transport by Band 3 of human resealed erythrocyte ghosts has been studied. The results show that a transmembrane Ca2+ gradient is essential for the conformation of erythrocyte Band 3 with higher anion transport activity. The dissipation of the transmembrane Ca2+ gradient by the ionophore A23187 inhibits the anion transport activity. The extent of this inhibition approaches 90% as the Ca2+ concentration on both sides of the ghost membrane is increased to 1.0 mM and half-maximum inhibition is observed at 0.25 mM Ca2+. Addition of ATP (0.4 mM) to the resealing medium can partly reestablish the transmembrane Ca2+ gradient by activation of Ca2+-ATPase and alleviate the inhibition to some extent. N-ethylmaleimide, an inhibitor of erythrocyte Ca2+-ATPase, prevents such restoration. Electron micrographs reveal that numerous larger intramembranous particles can be observed on the P-faces of freeze-fractured resealed ghosts in the absence of a transmembrane Ca2+ gradient.

Chinese atractylodes (Atractylodes japonica Koidz.ez Kitam.) is a perennial herb in the Compositae family, and is widely distributed in China. The dried rhizomes of the plant are used in traditional Chinese medicine. During the summer of 2011, typical signs and symptoms of Sclerotinia rot were observed on Chinese atractylodes in a production field of Liaoning Province of China. Symptoms were observed in plants at the flowering stage, distributed in patches throughout the rows, and with a disease incidence of approximately 10 to 15%. The lower mature leaves of infected plants first became yellow and wilted, basal stem areas showed a black-brown rot at the same time under conditions of high humidity, and white cottony mycelium formed along the basal stem and soil surfaces. Ultimately, the basal stem and roots rotted and the plants wilted and died quickly. Black, irregular sclerotia (average 0.8 to 6.9 mm in diameter) were also observed within the pith cavity of split stems and rotted roots. The pathogen was isolated from symptomatic tissues and sclerotia, surface disinfested with 2% sodium hypochlorite, and cultured on potato dextrose agar (PDA) (1). The fungus was mesophilic, with an optimum temperature for mycelial growth in culture of about 20°C. Colonies on PDA produced masses of white aerial mycelium, with small white flocci distributed among sclerotia. After 2 weeks, sclerotia 0.5 to 4.5 mm in diameter were produced near the margin in a uniform distribution. Sclerotia were spherical, elongated, or fused to form irregular shapes and tightly attached to the agar surface by their under surface, which could be seen through the bottom of the petri dishes. DNA sequences of five replicates were obtained using the TianGen DNA secure plant kit. The internal transcribed spacer (ITS) region of rDNA was amplified with primers ITS1/ITS4 and sequenced. BLAST analysis of the 513-bp segment showed high similarity (99%) with a sequence of Sclerotinia nivalis (GenBank Accession No. AB516670). A representative sequence was deposited in GenBank (Accession No. JX294862). The fungus isolated from symptomatic tissues was identified as S. nivalis Saito on the basis of morphological and cultural characteristics (2,3) and ITS sequence analysis. Symptoms were reproduced in the greenhouse by inoculating the basal stem and roots of 15 atractylodes plants at the 7- to 10-leaf stage. Inoculum was prepared by macerating 14-day-old PDA cultures of the fungus in a blender and placing the mixture (approximately 20 g) into the potting medium of each plant. Sterile PDA was used to inoculate the five control plants. Plants were maintained in a greenhouse at 22 to 25°C and about 75% relative humidity. After 7 to 10 days, symptoms were similar to those in the fields. Lower leaves of inoculated plants became yellow and wilted, and infected plants died 2 weeks after inoculation, whereas control plants remained healthy. The pathogen was successfully recovered from symptomatic tissues, completing Koch's postulates. To our knowledge, this is the first report of Sclerotinia rot of Chinese atractylodes. Given its wide host range, S. nivalis has great potential to become an economically important plant pathogen. References: (1) W. G. Kim and W. D. Cho. Mycobiology 30:41, 2002. (2) G. Q. Li et al. Mycol. Res. 104:232, 2000. (3) I. Saito. Mycoscience 38:227, 1997.