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Elucidating the influence mechanisms of seed germination and seedling growth is important for revealing the natural regeneration of forest plantations. We collected the seeds from 58-year-old Quercus acutissima Carruth. forest, and the seeds were further divided into three classes: large, medium, and small, and sown under the forest gaps (I, 197.82 m2; II, 91.85 m2, III, understory) to observe seed germination and early seedling growth. Precipitation in the study area and soil moisture content in the forest gaps were also observed during the trial period. The results showed that the precipitation in 2019 was similar to that in 2020; both were significantly lower than the precipitation in 2021. The difference in soil water content between gaps I and II was not significant, and both were significantly lower than III. The order of seedling emergence rate in gaps was II > III > I, but the minimum was almost close to zero in I. Large and medium seeds showed significantly greater emergence rate than small seeds. The seedlings of II had higher seedling height, ground diameter, ground diameter relative growth rate, seedling biomass, root surface area, and root volume than those of III. Large seeds had the highest ground diameter, ground diameter relative growth rate, biomass, root mass ratio, root shoot ratio, and root surface area. Correlation analysis showed that seedling biomass was significantly and positively correlated with root surface area and root volume, and significantly and negatively correlated with specific root length and specific root surface area. The regulation of soil moisture in the gap and the adaptability related to seed size were two key factors influencing the seed germination and early seedling growth of Q. acutissima.

Pot experiments were performed to comparatively study the differences in 16 salt tolerance indices between the seedlings of six Salix matsudana clones under the stress of various concentrations of NaCl (0, 0.1%, 0.3%, 0.5%, and 0.7%), including the salt injury index, shoot fresh weight, root fresh weight, leaf water content, relative conductivity, malondialdehyde content, and antioxidant enzyme activity. The salt-tolerant clones and key indices of salt tolerance were selected. Transcriptome sequencing analysis was performed on the selected salt-tolerant and salt-sensitive clones under salt stress, and the links between the physiological indices of salt tolerance and gene expression were analyzed. Results: (1) Superoxide dismutase (SOD), peroxidase (POD), chlorophyll, and net photosynthetic rate were closely related to the salt tolerance of Salix matsudana at the seedling stage. The regression equation was constructed as follows: salt tolerance index (y) = 0.224x10 + 0.216x11 + 0.127x12 + 0.191x7 − 0.187 (x10 = chlorophyll, x11 = SOD, x12 = POD, x7 = net photosynthetic rate). (2) The number of differentially expressed genes between the seedlings of salt-tolerant and salt-sensitive clones varied with the time of exposure (0 h, 4 h, 12 h, and 24 h) to 200 mmol·L−1 NaCl stress. The most differentially expressed genes in Sm172 were detected upon 24 h vs. 4 h of salt treatment, while the most in Sm6 were in the 24 h vs. 0 h comparison. Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes analysis showed that several differentially expressed genes were involved in carotenoid biosynthesis and plant mitogen-activated protein kinase signaling pathways. The nine highly expressed transcription factor genes (Sm172-f2p30-2392, Sm172-f2p28-2386, Sm6-f8p60-2372, Sm6-f2p39-2263, Sm6-f16p60-2374, Sm6-f3p60-931, Sm6-f2p60-1067, Sm172-f3p54-1980, and Sm172-f3p54-1980) were closely correlated with the four key indices of salt tolerance. These genes could become genetic resources for salt tolerance breeding of Salix matsudana.

Photodynamic therapy (PDT) is a promising therapeutic method for cancer due to many advantages including non-invasion, highly localized tissue region, low toxicity, and insignificant side effects. However, the poor tissue penetration of visible light for activating the traditional photosensitizer confines the utilization of PDT in the treatment of tumors embedded in thick biotissues. Upconversion nanoparticles (UCNPs) can be used to fabricate near-infrared light-triggered nanophotosensitizers by loading organic dyes or coating with inorganic semiconductor nanocrystals such as TiO2 and ZnO for deep-tissue PDT. In addition, some UCNPs-based nanophotosensitizers exhibit remarkable imaging properties for tumor detection. Improvement in reactive oxygen species (ROS) production and imaging sensitivity is the prerequisite for the application of UCNPs-based nanophotosensitizers in cancer diagnosis and therapy. Here, a near-infrared light-driven nanophotosensitizer UST-Au was prepared by assembling Au nanoparticles (AuNPs) on the surface of polyethyleneimine-modified NaYF4:Yb,Tm@NaGdF4:Yb@SiO2@TiO2 nanocomposites (UST), and then labeled with radioactive iodine ions (131I−) by virtue of Au-I− affinity interaction. The effects of AuNPs dosage on the morphology, diameter, zeta potential, optical properties, ROS generating ability and iodine labeling performance of the product were studied. And the feasibility of 131I−-labeled UST-Au as a single photon emission computed tomography (SPECT) imaging probe was analyzed. The results showed that tunable amounts of AuNPs were immobilized on the surface of polyethyleneimine-coated UST and the obtained UST-Au produced more ROS than UST as exposed to 980 nm near-infrared light. As AuNPs was added to be 3 wt% of the mass of UST, the obtained nanophotosensitizer had a mean hydrodynamic diameter (258 nm), relatively high zeta potential (+22.4 mV), good colloidal stability and the optimal ROS generation ability. Unexceptionally, iodine ions were expeditiously labeled on UST-Au suspended in aqueous solution, and the amount of the bound iodine ions enhanced with the increase of the mass percent of Au in UST-Au. The radiolabeling yield of UST-Au-131I− was more than 95%. Furthermore, the iodine labeling reaction had negligibly negative effect on the colloidal stability and ROS production of the nanophotosensitizer. In general, all these unique properties of the nanophotosensitizer facilitate the potential application in SPECT imaging-guided photodynamic therapy against tumor.

This study investigates the impact of financial incentives and role of information and communication in textbook availability (especially those in local languages) in Zambia. It uses the difference-in-difference estimation method to identify the causal links among the factors. The data used for the study were collected in 2017 and 2019 for baseline and end-line information. The study shows that providing financial incentives to schools increases the likelihood of a school receiving textbooks by 0.126. This improvement is mainly driven by raising the likelihood of a school collecting the books from zone-center schools and District Education Board Secretaries offices, by 0.356 and 0.158, respectively. Providing financial incentives to District Education Board Secretaries does not have any impact on the likelihood of a school receiving textbooks. This is partly because the current textbook delivery practice in districts and communities relies heavily on the action of schools and less on District Education Board Secretaries. Thus, providing incentives directly to schools seems to intensify the current last-mile textbook distribution practice and has better results. In addition, providing information to schools on the availability of textbooks at District Education Board Secretaries offices improves the outcomes significantly with minimum cost.

In this paper, the combination of simulation and experiment is used to study the performance of composite members after buckling. Considering the influence of initial defects on the buckling performance of the members, using the basic theory of contact and friction and the method of nonlinear analysis, the model of the composite members was established by ABAQUS finite element software and analyzed. At the same time, the compression test of the composite member was carried out to verify the correctness of the simulation. Finally, the calculated length coefficient of the composite member are obtained, which lays a foundation for the overall analysis of the long-span space grid structure.

Traditional WebQuest-oriented inquiry learning cannot help students develop good scientific literacy, because students are very dependent on network resources. They cannot obtain reliable evidence, and they also cannot think independently. The result is that they cannot explore science deeply. With the development of the Internet of Things and social network, in this paper, we propose a preliminary model of learning-oriented social network. It targets on inquiry learning and makes use of the Internet of Things. Specifically, in order to accomplish the purpose of inquiry learning by observing the real world, our model adopts advanced technology to uniquely mark research objects, uses wireless sensors to measure the parameters of research objects, and takes advantage of the description and discussion of social network to explore the changes of research objects. At the end of this paper, we come up with the organization pattern and software structure of this kind of social network and also put forward the method of implementing inquiry learning based on this model.

(1996). Debating ‘Brain Drain’ in the Context of Globalisation. Compare: A Journal of Comparative and International Education: Vol. 26, No. 3, pp. 269-285.

The role of university personnel management in higher education has been re-examined at all levels in both China and the West during the past ten years. This role will become even more important over the next decade of low-development in higher education in China. But, what kinds of policy does China have regarding the management of university personnel? How have these policies contributed to the improvement of university personnel? Since the policies were made under special circumstances of reform in the country, do they leave problems for the future development of higher education? This article is intended to discuss these interesting issues and preference will of course be given to those policies which have predominated in the past ten years. In addition, for the better understanding of the following discussion and the special Chinese situation, ‘higher education˚s refers to the regular one and ‘university personnel˚s refers to full-time staff, both administrative and academic, in all higher e...