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

Capture on High Curvature Region: Aggregation of Colloidal Particle Bound to Giant Phospholipid Vesicles

A very recent observation on the membrane mediated attraction and ordered aggregation of colloidal particles bound to giant phospholipid vesicles (I. Koltover, J. O. R\"{a}dler, C. R. Safinya, Phys. Rev. Lett. {\bf 82}, 1991(1999)) is investigated theoretically within the frame of Helfrich curvature elasticity theory of lipid bilayer fluid membrane. Since the concave or waist regions of the vesicle possess the highest local bending energy density, the aggregation of colloidal beads on these places can reduce the elastic energy in maximum. Our calculation shows that a bead in the concave region lowers its energy $\sim 20 k_B T$. For an axisymmetrical dumbbell vesicle, the local curvature energy density along the waist is equally of maximum, the beads can thus be distributed freely with varying separation distance.Comment: 12 pages, 2 figures. REVte

A quality-assured dataset of nine radiation components observed at the Shangdianzi regional GAW station in China (2013–2022)

The New Baseline Surface Radiation (NBSR) system was established at the Shangdianzi (SDZ) regional Global Atmosphere Watch (GAW) station in 2013 to observe nine broadband radiation components, i.e. the global, direct, diffuse, and upwelling shortwave irradiance (GSWI, DSWI, DifSWI, and UpSWI); the photosynthetically active radiation (PAR); the ultraviolet irradiance (UVAI and UVBI); and the down- and upwelling longwave irradiance (DnLWI and UpLWI). To test the 1 min raw radiometric data, a Hybrid Algorithm for Radiation Data Quality Control (HARDQC) is presented in this study based on well-established methods, together with the solar irradiance dataset and the spectral features of the instrument bands. Subsequently, a NBSR dataset, which consists of radiation data at multiple timescales (i.e. 1 min, hourly, daily, monthly, monthly average hourly, and monthly average daily) over 2013–2022, is established and evaluated. Results show that more than 98.7 % of all radiation components passed the physical possibility test. The percentages of those that passed the extremely rare test are greater than 98.6 % for all radiation components except for the DnLWI (97.1 %). The percentages of those that passed the comparison test are greater than 83.3 % (GSWI), 78.3 % (DSWI), 81.7 % (DifSWI), 93.1 % (UpSWI), 88.9 % (PAR), 95.6 % (UVAI), 96.3 % (UVBI), 99.8 % (DnLWI), and 99.7 % (UpLWI), respectively. Due to data logger faults, removal of the instruments for calibration, and lightning strikes, some apparent data gaps in the upwelling radiation components (January 2015–August 2017) and all radiation components (December 2018; July to September 2021) were detected. Despite the existence of a few imperfections in the NBSR dataset, it is still reliable to apply it in many fields such as the validation of satellite products and numerical models, the investigation of relationships between radiation and atmospheric composition, and the detection of changes in the surface fluxes. The dataset described in this paper is available at https://doi.org/10.1594/PANGAEA.963330 (Quan et al., 2023b).</p

Internal R&amp;D or external asset growth? A closer look at CEO narcissism and entrepreneurial orientation

PurposeIn today\u27s competitive business environment, understanding how leadership traits shape outcomes is critical. Chief executive officer (CEO) narcissism, an intriguing and debated trait, raises questions about its impact on organisational behaviour, particularly regarding entrepreneurial orientation (EO). This study aims to examine how CEO narcissism affects EO, both as aggregate and specific measures, encompassing internal and external growth. It also considers the organisational context by examining how factors such as capital intensity, firm ownership and CEO duality moderate this relationship.Design/methodology/approachTo test the hypotheses, the authors used a sample of firms drawn from China\u27s ChiNext database (2008–2017). After an initial screening, the final sample consists of 251 CEOs from 239 companies. Data on CEO narcissism are collected from the firm\u27s official website and major online sources, whilst additional data are extracted from the WIND daabase. The authors use multiple regression and ordinary least squares (OLS) for data analysis.FindingsThe results show that CEO narcissism leads to external asset growth investments but not internal research and development (R&amp;D). There is a positive relationship between CEO narcissism and EO as an aggregate measure and also different managerial discretions play varying roles in the relationship. Specifically, capital intensity weakens this relationship, but state ownership strengthens it.Originality/valueThis study helps to clarify the relationship between CEO narcissism and EO and advances the literature by showing that firms\u27 EO actions may take various forms of innovation and venturing as new entry initiations of EO. The study findings have important implications for firms to capitalise on narcissistic CEOs\u27 entrepreneurial tendencies, balance internal R&amp;D and external asset growth and leverage various managerial discretions

Quantum Critical Dynamics of A Qubit Coupled to An Isotropic Lipkin-Meshkov-Glick Bath

We explore a dynamic signature of quantum phase transition (QPT) in an isotropic Lipkin-Meshkov-Glick (LMG) model by studying the time evolution of a central qubit coupled to it. We evaluate exactly the time-dependent purity, which can be used to measure quantum coherence, of the central qubit. It is found that distinctly different behaviors of the purity as a function of the parameter reveal clearly the QPT point in the system. It is also clarified that the present model is equivalent to an anti Jaynes-Cummings model under certain conditions.Comment: 8 pages, 4 figure