Impacts of Privatization on Employment - Evidence from China

This paper evaluates the impact of privatization on firm employment using a panel dataset of 386 firms in China in the period 1995-2001. Controlling firm and year fixed effects, our panel regressions find that employment grows faster in privatized firms than in pure state-owned firms by a margin of 17.7 percentage points over the base year of 1995. We also study the dynamic impact of privatization on employment growth and find that the performance of privatized firms improves over time. These findings are robust even after we control other performance and financial variables as well as the pre-privatization employment history of privatized firms. In addition, we employ the difference-in-dffierence propensity score matching method to check the robustness of our results. The estimates cofinrm the regression-based results.Labor Demand, Comparison of Public and Private Enterprises, Privatization, Socialist Enterprises and Their Transitions, China

Quantitative evaluation of the immunodeficiency of a mouse strain by tumor engraftments

© 2015 Ye et al. Background: The mouse is an organism that is widely used as a mammalian model for studying human physiology or disease, and the development of immunodeficient mice has provided a valuable tool for basic and applied human disease research. Following the development of large-scale mouse knockout programs and genome-editing tools, it has become increasingly efficient to generate genetically modified mouse strains with immunodeficiency. However, due to the lack of a standardized system for evaluating the immuno-capacity that prevents tumor progression in mice, an objective choice of the appropriate immunodeficient mouse strains to be used for tumor engrafting experiments is difficult. Methods: In this study, we developed a tumor engraftment index (TEI) to quantify the immunodeficiency response to hematologic malignant cells and solid tumor cells of six immunodeficient mouse strains and C57BL/6 wild-type mouse (WT). Results: Mice with a more severely impaired immune system attained a higher TEI score. We then validated that the NOD-scid-IL2Rg-/- (NSI) mice, which had the highest TEI score, were more suitable for xenograft and allograft experiments using multiple functional assays. Conclusions: The TEI score was effectively able to reflect the immunodeficiency of a mouse strain.Link_to_subscribed_fulltex

Differential distribution of phytochemicals in Scutellariae Radix and Scutellariae Amoenae Radix using microscopic mass spectrometry imaging

Scutellariae Radix, the root of Scutellaria baicalensis Georgi, is widely applied in China for the treatment of fever, ulcer, bronchitis, hepatitis and inflammatory symptoms. Sctuellariae Amoenae Radix, the root of Scutellaria amoena C.H. Wright, is often prescribed as the substitute for Scutellariae Radix. Up to now, no attempt has been made to unveil and compare the localization of phytochemicals in Scutellariae Radix and its succedaneum. This investigation succeeded to look into the differential distribution of natural compounds in Scutellariae Radix and Scutellariae Amoenae Radix using microscopic mass spectrometry imaging. Compounds presenting different distribution modes in two kinds of roots were sorted out, then a quick method for the differentiation between Scutellariae Radix and Scutellariae Amoenae Radix was established. Accumulation sites of baicalein, baicalin, wogonin and wogonoside in Scutellariae Radix were also uncovered using microscopic mass spectrometry imaging. Moreover, the application of matrix assisted laser desorption ionization-quadrupole-time of flight mass spectrometry allowed the on-tissue dissociation of major flavonoids. Overall, the utilization of microscopic mass spectrometry imaging and matrix assisted laser desorption ionization-quadrupole-time of flight mass spectrometry provided a novel perspective for the discovery of natural compounds within medicinal plants

Mono-Mercury Doping of Au₂₅ and the HOMO/LUMO Energies Evaluation Employing Differential Pulse Voltammetry

Controlling the bimetal nanoparticle with atomic monodispersity is still challenging. Herein, a monodisperse bimetal nanoparticle is synthesized in 25% yield (on gold atom basis) by an unusual replacement method. The formula of the nanoparticle is determined to be Au₂₄Hg₁(PET)₁₈ (PET: phenylethanethiolate) by high-resolution ESI-MS spectrometry in conjunction with multiple analyses including X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). X-ray single-crystal diffraction reveals that the structure of Au₂₄Hg₁(PET)₁₈ remains the structural framework of Au₂₅(PET)₁₈ with one of the outer-shell gold atoms replaced by one Hg atom, which is further supported by theoretical calculations and experimental results as well. Importantly, differential pulse voltammetry (DPV) is first employed to estimate the highest occupied molecular orbit (HOMO) and the lowest unoccupied molecular orbit (LUMO) energies of Au₂₄Hg₁(PET)₁₈ based on previous calculations

Mono-cadmium vs Mono-mercury Doping of Au₂₅ Nanoclusters

Controlling the dopant type, number, and position in doped metal nanoclusters (nanoparticles) is crucial but challenging. In the work described herein, we successfully achieved the mono-cadmium doping of Au₂₅ nanoclusters, and revealed using X-ray crystallography in combination with theoretical calculations that one of the inner-shell gold atoms of Au₂₅ was replaced by a Cd atom. The doping mode is distinctly different from that of mono-mercury doping, where one of the outer-shell Au atoms was replaced by a Hg atom. Au₂₄Cd is readily transformed to Au₂₄Hg, while the reverse (transformation from Au₂₄Hg to Au₂₄Cd) is forbidden under the investigated conditions

Structure of Chiral Au₄₄(2,4-DMBT)₂₆ Nanocluster with an 18-Electron Shell Closure

The 18-electron shell closure structure of Au nanoclusters protected by thiol ligands has not been reported until now. Herein, we synthesize a novel nanocluster bearing the same gold atom number but a different thiolate number as another structurally resolved nanocluster Au₄₄(TBBT)₂₈ (TBBTH = 4-<i>tert</i>-butylbenzenelthiol). The new cluster was determined to be Au₄₄(2,4-DMBT)₂₆ (2,4-DMBTH = 2,4-dimethylbenzenethiol) using multiple techniques, including mass spectrometry and single crystal X-ray crystallography (SCXC). Au₄₄(2,4-DMBT)₂₆ represents the first 18-electron closed-shell gold nanocluster. SCXC reveals that the atomic structure of Au₄₄(2,4-DMBT)₂₆ is completely different from that of Au₄₄(TBBT)₂₈ but is similar to the structure of Au_38Q. The arrangement of staples (bridging thiolates) and part of the Au₂₉ kernel atom induces the chirality of Au₄₄(2,4-DMBT)₂₆. The finding that a small portion of the gold kernel exhibits chirality is interesting because it has not been previously reported to the best of our knowledge. Although Au₄₄(2,4-DMBT)₂₆ bears an 18-electron shell closure structure, it is less thermostable than Au₄₄(TBBT)₂₈, indicating that multiple factors contribute to the thermostability of gold nanoclusters. Surprisingly, the small difference in Au/thiolate molar ratio between Au₄₄(2,4-DMBT)₂₆ and Au₄₄(TBBT)₂₈ leads to a dramatic distinction in Au 4f X-ray photoelectron spectroscopy, where it is found that the charge state of Au in Au₄₄(2,4-DMBT)₂₆ is remarkably more positive than that in Au₄₄(TBBT)₂₈ and even slightly more positive than the charge states of gold in Au-(2,4-DMBT) or Au-TBBT complexes