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Homeostatic plasticity is engaged when neurons need to stabilize their synaptic strength and excitability in response to acute or prolonged destabilizing changes in global activity. Compared to the extensive studies investigating the molecular mechanisms for homeostatic synaptic plasticity, the mechanism underlying homeostatic intrinsic plasticity is largely unknown. Through whole-cell patch-clamp recording in low-density cultures of dissociated hippocampal neurons, we demonstrate here that prolonged activity blockade induced by the sodium channel blocker tetrodotoxin (TTX) leads to increased action potential firing rates. Conversely, prolonged activity enhancement induced by the A-type gamma-aminobutyric acid receptor antagonist bicuculline (BC) results in decreased firing rates. Prolonged activity enhancement also enhanced potassium (K + ) current through K v 1 channels, suggesting that changes in K + current, in part, mediate stabilization of hippocampal neuronal excitability upon prolonged activity elevation. In contrast to the previous reports showing that L-type voltage-gated calcium (Ca 2+ ) channels solely mediate homeostatic regulation of excitatory synaptic strength ( Ibata et al., 2008; Goold and Nicoll, 2010 ), inhibition of N -Methyl- d -aspartate (NMDA) receptors alone mimics the elevation in firing frequency driven by prolonged TTX application, while the decrease in firing rates induced by prolonged BC treatment involves the activity of NMDA receptors and L-type voltage-gated Ca 2+ channels. These results collectively provide strong evidence that alterations in Ca 2+ influx through NMDA receptors and L-type voltage-gated Ca 2+ channels mediate homeostatic intrinsic plasticity in hippocampal neurons in response to prolonged activity changes. [ABSTRACT FROM AUTHOR]

Abstract: It has been reported that ipriflavone was primarily metabolized via hepatic microsomal cytochrome P450 (CYP) 1A1/2 and 2C11 in rats, and the expression of hepatic CYP1A2 and 2C11 was not changed in rats with water deprivation for 72h compared to controls. Hence, it could be expected that the time-averaged nonrenal clearance (Clnr) of ipriflavone would be comparable between two groups of rat. As expected, after intravenous administration of ipriflavone (20mg/kg), the Clnr values of ipriflavone were comparable between two groups of rat. This could be supported by comparable in vitro intrinsic clearance (Clint) values for the disappearance of ipriflavone in hepatic microsomes for both groups of rat. After oral administration of ipriflavone (200mg/kg), the total area under the plasma concentration–time curve from time zero to the last measured time, 12h, in plasma (AUC0–12h) values of ipriflavone were also comparable between two groups of rat. The above data suggest that dehydration state did not affect significantly pharmacokinetics of ipriflavone in rats. [Copyright &y& Elsevier]

Abstract: Growth rates of high-purity single-crystal 6H-SiC have been studied as a function of growth conditions during chemical vapor deposition process using silicon tetrachloride, propane, and hydrogen as reactants. The growth temperature ranged from 2000 to 2150°C. High-quality SiC crystals were deposited at growth rates in the 100–300μm/h range in both silicon- and carbon-supply limited regimes by adjusting flows of all three reactants. The results have been interpreted using thermodynamic equilibrium calculations. [Copyright &y& Elsevier]

Abstract: Cerium-substituted bismuth titanate (Bi3.25Ce0.75Ti3O12 (BCT)) films were deposited on the Pt(111)/SiO2/Si(100) substrates by a liquid source misted chemical deposition technique. This film showed X-ray diffraction patterns that crystallization along the (006) direction was suppressed and did not contain any other oxides. The remnant polarization of this film increased with increase in annealing temperature. The 2P r and 2E c values of the BCT film annealed at 700 °C were 19.72 μC/cm2 and 357 kV/cm, respectively. 2P r value of this film decreased by less than 5% of the initial value after 7×109 read/write switching cycles at a frequency of 1 MHz. [Copyright &y& Elsevier]

The kinetics and mechanism of probe-induced oxide growth on an octadecyltrichlorosilane (OTS) self-assembled monolayer (SAM) passivated native-SiO2/Si surface have been investigated using atomic force microscopy (AFM). It was found that oxidation strongly depends on tip polarity and the local chemistry of OTS molecules. At negative tip voltage, oxide grows and the oxidation involves a decomposition and depletion of OTS SAM. While under positive tip bias, OTS molecules are partially degraded. The dielectrical properties of the oxide were characterized by I–V measurements using current sensing AFM. The barrier height of AFM grown oxide, in comparison with thermal oxide and OTS SAM, was determined. Current spikes relating to the release of single charge were also observed on the I–V curves of AFM oxide. [Copyright &y& Elsevier]

The life cycle of Giardia lamblia contains two differentiation processes, encystation and excystation. We performed an experiment to identify the genes induced during encystation using the differential display reverse transcriptase–polymerase chain reaction. Three of twelve isolated cDNA clones that showed increased transcription during encystation were identified to be of the myb2, which encodes a well-known transcriptional factor involved in cellular development and differentiation. The amino acid sequences of the Myb2 protein deduced from the isolated gene revealed that this Myb2 has a DNA binding domain comprising two imperfect repeats at its carboxyl-terminus. The nuclear localization of Myb2 protein during encystation was observed in vivo by expressing a Myb2-GFP fusion protein. In a random site selection experiment, the oligonucleotides bound by rMyb2 contained a conserved sequence of GTTT(G/T)(G/T). Two promoters of the encystation-induced genes, myb2, and cwp1, were also found to bind to rMyb2, whereas gap1, one of the constitutive genes did not. [Copyright &y& Elsevier]

Abstract: The major carbohydrate of pulse seeds is starch, which accounts for 22–45% of the dry matter. In recent years, substantial progress has been made on the molecular structure of cereal and tuber starches and their impact on functionality. Similar studies on pulse starches are limited. This review summarizes the present status of knowledge on the isolation, composition, molecular structure, properties and modification of pulse starches. Future research needs in the area of pulse starches are outlined. [Copyright &y& Elsevier]

Abstract: A high-pressure, double-chamber, fan-stirred, large-scale explosion facility is proposed for measurements of laminar and turbulent burning velocities, S L and S T, of centrally-ignited hydrogen and carbon monoxide syngas/air mixtures over an initial pressure range of p = 0.1–1.0 MPa. Results show that lean syngas laminar flames at elevated pressure are highly unstable resulting in cellular structures all over the expanding flame front surface, where S L∼p −0.15 having a relatively modest decrease with pressure as compared to lean methane flames where S L∼p −0.50. Contrarily, as to lean syngas turbulent flames, values of S T increase with increasing pressure (S T∼p 0.15) at a fixed r.m.s. turbulent fluctuating velocity (u′ ≈ 1.4 m/s). Moreover, it is also shown that increasing u′/S L is still a way much more effective in increasing values of S T/S L than increasing pressure. Finally, discussions are offered and area for further studies identified. [Copyright &y& Elsevier]

Abstract: Physicochemical, microbiological and sensorial qualities of cooked pork patty coated with pectin-based material containing green tea leaf extract powder were studied. Cooked pork patties were separated into three groups; uncoated control (C), coated with pectin-based materials (CP), and coated with pectin-based materials containing 0.5% green tea powder (CGP). The prepared patties were irradiated at 0 and 3kGy using cobalt-60 gamma rays. Lipid oxidation, free radical scavenging effects, moisture content, total plate count, and sensory properties were evaluated during storage for 14days at 10°C. Lipid oxidation decreased (p ⩽0.05) and radical scavenging (p ⩽0.05) increased in the pork patties in CGP or CP relative to those of the controls when vacuum packaged. Coated patties contained higher moisture contents than the controls in both air- and vacuum packagings. The numbers of total aerobic bacteria were significantly reduced by the coating treatments as well as by irradiation. No difference were detected in sensory characteristics due to gamma irradiation or coating treatments. [Copyright &y& Elsevier]