Sonication assisted Agrobacterium-mediated transformation of chalcone synthase (CHS) gene to Spring Dendrobium cultivar ‘Sanya’

In this study, a protocol was developed to obtain stable lines of the Spring Dendrobium cultivar ‘Sanya’ via sonication assisted Agrobacterium-mediated transformation (SAAT) of protocorm-like bodies (PLBs). Agrobacterium tumefaciens strain LBA4404 was used with the binary vector AG205 containing the chalcone synthase (CHS) gene for flower color change and the neomycin phosphotransferase II gene (NPTIIgene) as a selectable marker for kanamycin resistance. PLBs were treated for 10 min using ultrasound (40 KHz) and subsequently immersed in the Agrobacterium suspension for 60 min. The addition of 100 M acetosyringone (AS) during the pre-culture and co-culture achieved the highest efficiency of gene transformation (0.5%). Following co-cultivation, PLBs were cultured on selective medium containing 200 mgL-1 kanamycin and 250 mgL-1 cefotaxime. Proliferating PLBs were repeatedly selected for kanamycin resistance and stable transformed lines were generated. Incorporation and expression of transgenes were confirmed by PCR analysis, southern blot analysis and reverse transcription-quantitative real-time PCR (RT-PCR). A total of five southern blot positive lines were obtained from co-cultivated PLBs.Key words: Spring Dendrobium cultivar ‘Sanya’, chalcone synthase (CHS) gene, transformation, sonication assisted Agrobacterium-mediated transformation (SAAT), protocorm-like bodies (PLBs)

Monte Carlo Simulation of HERD Calorimeter

The High Energy cosmic-Radiation Detection (HERD) facility onboard China's Space Station is planned for operation starting around 2020 for about 10 years. It is designed as a next generation space facility focused on indirect dark matter search, precise cosmic ray spectrum and composition measurements up to the knee energy, and high energy gamma-ray monitoring and survey. The calorimeter plays an essential role in the main scientific objectives of HERD. A 3-D cubic calorimeter filled with high granularity crystals as active material is a very promising choice for the calorimeter. HERD is mainly composed of a 3-D calorimeter (CALO) surrounded by silicon trackers (TK) from all five sides except the bottom. CALO is made of 9261 cubes of LYSO crystals, corresponding to about 55 radiation lengths and 3 nuclear interaction lengths, respectively. Here the simulation results of the performance of CALO with GEANT4 and FLUKA are presented: 1) the total absorption CALO and its absorption depth for precise energy measurements (energy resolution: 1\% for electrons and gamma-rays beyond 100 GeV, 20\% for protons from 100 GeV to 1 PeV); 2) its granularity for particle identification (electron/proton separation power better than $10^{-5}$); 3) the homogenous geometry for detecting particles arriving from every unblocked direction for large effective geometrical factor ($>$3 ${\rm m}^{2}{\rm sr}$ for electron and diffuse gamma-rays, $>$2 ${\rm m}^{2}{\rm sr}$ for cosmic ray nuclei); 4) expected observational results such as gamma-ray line spectrum from dark matter annihilation and spectrum measurement of various cosmic ray chemical components

When Things Matter: A Data-Centric View of the Internet of Things

With the recent advances in radio-frequency identification (RFID), low-cost wireless sensor devices, and Web technologies, the Internet of Things (IoT) approach has gained momentum in connecting everyday objects to the Internet and facilitating machine-to-human and machine-to-machine communication with the physical world. While IoT offers the capability to connect and integrate both digital and physical entities, enabling a whole new class of applications and services, several significant challenges need to be addressed before these applications and services can be fully realized. A fundamental challenge centers around managing IoT data, typically produced in dynamic and volatile environments, which is not only extremely large in scale and volume, but also noisy, and continuous. This article surveys the main techniques and state-of-the-art research efforts in IoT from data-centric perspectives, including data stream processing, data storage models, complex event processing, and searching in IoT. Open research issues for IoT data management are also discussed

H∞ Norm Computation for Descriptor Symmetric Systems

This paper deals with the problem of H∞ norm computation for general symmetric systems and descriptor symmetric systems. The computation of H∞ norm for state-space symmetric systems is extended to descriptor symmetric systems. An explicit expression is given based on the bound real lemma (BRL), and the generalized bound real lemma (GBRL). The results have obvious computational advantages, especially for large scale descriptor symmetric systems. Additionally, two numerical examples are presented to demonstrate the feasibility and effectiveness of the results

Edge Influence Computation in Dynamic Graphs

Reachability queries are of great importance in many research and application areas, including general graph mining, social network analysis and so on. Many approaches have been proposed to compute whether there exists one path from one node to another node in a graph. Most of these approaches focus on static graphs, however in practice dynamic graphs are more common. In this paper, we focus on handling graph reachability queries in dynamic graphs. Specifically we investigate the influence of a given edge in the graph, aiming to study the overall reachability changes in the graph brought by the possible failure/deletion of the edge. To this end, we firstly develop an efficient update algorithm for handling edge deletions. We then define the edge influence concept and put forward a novel computation algorithm to accelerate the computation of edge influence. We evaluate our approach using several real world datasets. The experimental results show that our approach outperforms traditional approaches significantly

Multiparty simultaneous quantum identity authentication based on entanglement swapping

We present a multiparty simultaneous quantum identity authentication protocol based on entanglement swapping. In our protocol, the multi-user can be authenticated by a trusted third party simultaneously

A Cellular Automata Model with Probability Infection and Spatial Dispersion

In this article, we have proposed an epidemic model by using probability cellular automata theory. The essential mathematical features are analyzed with the help of stability theory. We have given an alternative modelling approach for the spatiotemporal system which is more realistic and satisfactory from the practical point of view. A discrete and spatiotemporal approach are shown by using cellular automata theory. It is interesting to note that both size of the endemic equilibrium and density of the individual increase with the increasing of the neighborhood size and infection rate, but the infections decrease with the increasing of the recovery rate. The stability of the system around the positive interior equilibrium have been shown by using suitable Lyapunov function. Finally experimental data simulation for SARS disease in China and a brief discussion conclude the paper

The Dynamics of Sustained Reentry in a Loop Model with Discrete Gap Junction Resistance

Dynamics of reentry are studied in a one dimensional loop of model cardiac cells with discrete intercellular gap junction resistance ($R$). Each cell is represented by a continuous cable with ionic current given by a modified Beeler-Reuter formulation. For $R$ below a limiting value, propagation is found to change from period-1 to quasi-periodic ($QP$) at a critical loop length ($L_{crit}$) that decreases with $R$. Quasi-periodic reentry exists from $L_{crit}$ to a minimum length ($L_{min}$) that is also shortening with $R$. The decrease of $L_{crit}(R)$ is not a simple scaling, but the bifurcation can still be predicted from the slope of the restitution curve giving the duration of the action potential as a function of the diastolic interval. However, the shape of the restitution curve changes with $R$.Comment: 6 pages, 7 figure

Assessment of molecular detection of anaerobic ammonium-oxidizing (anammox) bacteria in different environmental samples using PCR primers based on 16S rRNA and functional genes

This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this recordEleven published PCR primer sets for detecting genes encoding 16S ribosomal RNA (rRNA), hydrazine oxidoreductase (HZO), cytochrome cd1-containing nitrite reductase (NirS), and hydrazine synthase subunit A (HzsA) of anaerobic ammonium-oxidizing (anammox) bacteria were assessed for the diversity and abundance of anammox bacteria in samples of three environments: wastewater treatment plant (WWTP), wetland of Mai Po Nature Reserve (MP), and the South China Sea (SCS). Consistent phylogenetic results of three biomarkers (16S rRNA, hzo, and hzsA) of anammox bacteria were obtained from all samples. WWTP had the lowest diversity with Candidatus Kuenenia dominating while the SCS was dominated by Candidatus Scalindua. MP showed the highest diversity of anammox bacteria including C. Scalindua, C. Kuenenia, and Candidatus Brocadia. Comparing different primer sets, no significant differences in specificity for 16S rRNA gene could be distinguished. Primer set CL1 showed relatively high efficiency in detecting the anammox bacterium hzo gene from all samples, while CL2 showed greater selectivity for WWTP samples. The recently reported primer sets of the hzsA gene resulted in high efficiencies in detecting anammox bacteria while nirS primer sets were more selective for specific samples. Results collectively indicate that the distribution of anammox bacteria is niche-specific within different ecosystems and primer specificity may cause biases on the diversity detected.This research project was supported in part by a Ph.D. studentship from The University of Hong Kong (PH), Research Grant Council GRF Project (Grant No. 701913) (J-DG), Shenzhen Science and Technology Innovation Commission (Grant no. KQCX2015032416053646) (ML), Leaderman & Associates in Taipei (JGL), and additional financial support of Environmental Toxicology Education and Research Fund of this laboratory