Physicochemical properties of silkworm larvae protein isolate and gastrointestinal hydrolysate bioactivities

The objectives of this study were to investigate the amino acid composition and thermal properties of silkworm larvae protein isolate (SLPI) and to evaluate the in vitro angiotensin-converting enzyme (ACE) inhibitory and antioxidant activities of its hydrolysate prepared with gastrointestinal enzymes. The results showed that, SLPI was a high quality protein source with a well-balanced composition of essential amino acids, which was especially rich in glutamic acid (13.79 g/100 g protein), aspartic acid (10.44 g/100 g protein), leucine (8.68 g/100 g protein), lysine (8.01 g/100 g protein) and arginine (6.59 g/100 g protein). In additon, three endothermic denaturation transitions were observed in DSC thermograms of SLPI. The maximum transition peak occurred in the third thermal transition, which denaturation temperature (Td), peak temperature of denaturation (Tp) and enthalpy change (ΔH) were 76.95°C, 80.42°C and 783.75 J/g, respectively. SLPI hydrolysate exhibited strong ACE-inhibitory activity (IC50=8.3 μg/ml) and relatively higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (IC50=57.91 μg/ml) and ferrous ions chelating capacity (IC50=2.03 mg/ml). Moreover, the  hydrolysate showed notable reducing power. It was concluded that, SLPI might be considered as a multifunctional ingredients for functional foods with protein supplements, ACE-inhibitory and antioxidant activity.Key words: Silkworm larvae protein isolates (SLPI), amino acid composition, thermal properties, gastrointestinal enzymes, hydrolysis, ACE inhibition, antioxidant

On the Hardware/Software Design and Implementation of a High Definition Multiview Video Surveillance System

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DNA regulatory motif selection based on support vector machine (SVM) and its application in microarray experiment of Kashin-Beck disease

Conserved DNA sequences are essential to investigate the regulation and expression of nearby genes. The conserved regions can interact with certain proteins and can potentially determine the transcription speed and amount of the corresponding mRNA in gene replication process. In this paper, motifs of coexpressed genes of microarray experiments were explored with discovery algorithms. Then a selection algorithm based on support vector machine (SVM) was applied to identify those motifs which mostly influenced gene expression. This method combined the advantages from both matrix based motif finding and functional motif selection. When applied to Kashin-Beck disease (KBD), this method identified 9 motifs, and revealed that some motifs may be related to the immune reactions. In addition, we suggested that the methods used could be applied to other microarray experiments to explore the underlying relationships between motif types and gene functions.Key words: Support vector machine (SVM), microarray, motif discovery, gene regulation, Kashin-Beck disease

Regulation of cytokinesis by spindle-pole bodies

Author Posting. © The Author(s), 2006. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature Cell Biology 8 (2006): 891-893, doi:10.1038/ncb1449.In the fission yeast Schizosaccharomyces pombe, cytokinesis is thought to be controlled by the daughter spindle pole body (SPB) through a regulatory pathway, the Septation Initiation Network (SIN). Here we demonstrate that laser ablation of both but not a single SPB results in cytokinesis failure. Ablation of just the daughter SPB often leads to activation of the SIN on the mother and successful cytokinesis. Thus, either SPB can drive cytokinesis.This work was supported by National Institutes of Health grants GMS 59363 (to A.K.), GMS 69670 (to F.C), and by the Human Frontiers Science Program grant RGP0064 (to AK)

Control of Emi2 activity and stability through Mos-mediated recruitment of PP2A.

Before fertilization, vertebrate eggs are arrested in meiosis II by cytostatic factor (CSF), which holds the anaphase-promoting complex (APC) in an inactive state. It was recently reported that Mos, an integral component of CSF, acts in part by promoting the Rsk-mediated phosphorylation of the APC inhibitor Emi2/Erp1. We report here that Rsk phosphorylation of Emi2 promotes its interaction with the protein phosphatase PP2A. Emi2 residues adjacent to the Rsk phosphorylation site were important for PP2A binding. An Emi2 mutant that retained Rsk phosphorylation but lacked PP2A binding could not be modulated by Mos. PP2A bound to Emi2 acted on two distinct clusters of sites phosphorylated by Cdc2, one responsible for modulating its stability during CSF arrest and one that controls binding to the APC. These findings provide a molecular mechanism for Mos action in promoting CSF arrest and also define an unusual mechanism, whereby protein phosphorylation recruits a phosphatase for dephosphorylation of distinct sites phosphorylated by another kinase

Delocalized single-photon Dicke states and the Leggett- Garg inequality in solid state systems

We show how to realize a single-photon Dicke state in a large one-dimensional array of two- level systems, and discuss how to test its quantum properties. Realization of single-photon Dicke states relies on the cooperative nature of the interaction between a field reservoir and an array of two-level-emitters. The resulting dynamics of the delocalized state can display Rabi-like oscillations when the number of two-level emitters exceeds several hundred. In this case the large array of emitters is essentially behaving like a mirror-less cavity. We outline how this might be realized using a multiple-quantum-well structure and discuss how the quantum nature of these oscillations could be tested with the Leggett-Garg inequality and its extensions.Comment: 29 pages, 5 figures, journal pape

Metal-insulator transition in vanadium dioxide nanobeams: probing sub-domain properties of strongly correlated materials

Many strongly correlated electronic materials, including high-temperature superconductors, colossal magnetoresistance and metal-insulator-transition (MIT) materials, are inhomogeneous on a microscopic scale as a result of domain structure or compositional variations. An important potential advantage of nanoscale samples is that they exhibit the homogeneous properties, which can differ greatly from those of the bulk. We demonstrate this principle using vanadium dioxide, which has domain structure associated with its dramatic MIT at 68 degrees C. Our studies of single-domain vanadium dioxide nanobeams reveal new aspects of this famous MIT, including supercooling of the metallic phase by 50 degrees C; an activation energy in the insulating phase consistent with the optical gap; and a connection between the transition and the equilibrium carrier density in the insulating phase. Our devices also provide a nanomechanical method of determining the transition temperature, enable measurements on individual metal-insulator interphase walls, and allow general investigations of a phase transition in quasi-one-dimensional geometry.Comment: 9 pages, 3 figures, original submitted in June 200

Observation of long-lived interlayer excitons in monolayer MoSe2–WSe2 heterostructures

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Antikaon production in nucleon-nucleon reactions near threshold

The antikaon production cross section from nucleon-nucleon reactions near threshold is studied in a meson exchange model. We include both pion and kaon exchange, but neglect the interference between the amplitudes. In case of pion exchange the antikaon production cross section can be expressed in terms of the antikaon production cross section from a pion-nucleon interaction, which we take from the experimental data if available. Otherwise, a $K^*$-resonance exchange model is introduced to relate the different reaction cross sections. In case of kaon exchange the antikaon production cross section is related to the elastic $KN$ and $\bar KN$ cross sections, which are again taken from experimental measurements. We find that the one-meson exchange model gives a satisfactory fit to the available data for the $NN\to NNK\bar K$ cross section at high energies. We compare our predictions for the cross section near threshold with an earlier empirical parameterization and that from phase space models.Comment: 16 pages, LaTeX, 5 postscript figures included, submitted to Z. Phys.