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The tuning of diastereoselectivity in the Mannich reaction of glycine ester with N-tosyl imines through electronic adjustment of the ligand is achieved. Either syn- or anti-diamino acid derivatives is obtained in excellent diastereo- and enantioselectivities by ligand modification.

Graphical Abstract

Self‐repair of critical bone defects from periodontitis, tumor resection, and trauma is difficult. Osteoporosis is an abnormal bone metabolism disease characterized by increased bone resorption, decreased bone formation, and decreased activity of bone marrow mesenchymal stem cells (BMSCs), which further inhibits the repair of bone defects. Improving the osteogenic ability of BMSCs after osteoporosis is an important step in treating osteoporotic bone defects. Hydroxyapatite (HA) with good biocompatibility is widely used in bone material research. HA and strontium‐doped hydroxyapatite (Sr‐HA) microspheres are synthesized following a hydrothermal method, and the characteristics and the ability of these microspheres are explored to promote osteogenesis. Further, the role of the calcium‐sensing receptor (CaSR) and Janus kinase 2 gene/signal transducers and activators of transcription 3 (JAK2/STAT3) signaling pathway in this process are investigated. The results show that Sr‐HA, rather than HA alone, significantly promote the osteogenic differentiation of BMSCs in vitro and bone formation in vivo. Further, the effect of promoting osteogenic differentiation is realized by activating the CaSR‐JAK2/STAT3 signaling pathway. Therefore, the study demonstrates that Sr‐HA is the better choice for restoring critical bone defects.

To provide a theoretical basis for alpine source lake protection, ten samples were taken from each lake annually from 2012 to 2015. Each year, the various species of nitrogen and phosphorus nutrients were measured. The average contents of nitrate nitrogen, ammonia nitrogen, nitrite nitrogen, total phosphorus, and total nitrogen in the four lakes are 0.195-0.0 mg/L, 0.038-0.143 mg/L, 0.004-0.168 mg/L, 0.006-0.740 mg/L, and 0.050-0.547 mg/L, respectively. The total phosphorus contents in Eling Lake, Longbao Lake and Sea Star were higher than Class I water quality standards, and the total nitrogen contents in Eling Lake, Sea Star and Zhaling Lake were higher than Class I water quality standards as well. The concentration contour maps of the nitrate nitrogen, ammonia nitrogen, nitrite nitrogen, total phosphorus and total nitrogen showed that the indicators of the four lakes in the east, the west, and the center of the lake did not have the same trend. From 2012 to 2015, each of the measured nutrients showed a rising trend year by year. The four lakes are polluted by both endogenous and exogenous pollution, and it is necessary to limit the exogenous pollution and protect the alpine lakes immediately. [ABSTRACT FROM AUTHOR]

AIM: To explore the topographic distribution features of choroidal thickness (CT) and retinal nerve fiber layer thickness (RNFLT), and determine the relationship between CT and ocular parameters in school-aged children. METHODS: The healthy school-aged children with low ametropia or emmetropia in Wenzhou were recruited for this cross-sectional study. With high-density optical coherence tomography (HD-OCT) combined with MATLAB software, the CT and RNFLT values in the macular area were measured at different locations and compared. Statistical analyses were performed to evaluate the correlation between CT and ophthalmic parameters, such as spherical equivalent (SE) and the axial length (AL). RESULTS: A total of 279 school-aged children with 8.00±1.35 years of mean age (range, 6-10y) were included. The mean AL was 23.66±0.86 mm. The mean CT in CT-C (264.31±48.93 µm) was thicker than that in CT-N1 (249.54±50.52 µm), and the average CT in the parafoveal region was also thicker than that in CT-N2 (235.65±50.63 µm). The subfoveal CT also varied substantially across refractive errors (P

[Retraction]AIM: To explore the topographic distribution features of choroidal thickness (CT) and retinal nerve fiber layer thickness (RNFLT), and determine the relationship between CT and ocular parameters in school-aged children. METHODS: The healthy school-aged children with low myopia or emmetropia in Wenzhou were recruited for this cross-sectional study. With high-density optical coherence tomography (HD-OCT) combined with MATLAB software, the CT and RNFLT values in the macular area were measured at different locations and compared. Statistical analyses were performed to evaluate the correlation between CT and ophthalmic parameters, such as spherical equivalent (SE) and the axial length (AL). RESULTS: A total of 279 school-aged children with 8.00±1.35 years of mean age (range, 6-10y) were included. The mean AL was 23.66±0.86 mm. The mean CT in CT-C (264.31±48.93 µm) was thicker than that in CT-N1 (249.54±50.52 µm), and the average CT in the parafoveal region was also thicker than that in CT-N2 (235.65±50.63 µm). The subfoveal CT also varied substantially across refractive errors (P

We investigated the distribution and chemical speciation of Cd, Cr, Cu, Pb and Zn in the water level-fluctuating (WLF) zone of the main stream (MS) and tributaries (ZX and MX) of the Three Gorges Reservoir. We evaluated the ecological risk and pollution level from heavy metals based on the Potential Ecological Risk Index (RI), Risk Assessment Code (RAC), and Ratio of Secondary Phase and Primary Phase (RSP). Our results indicated that the total and bio-available heavy metal contents were higher in the tributaries than in the MS. Moderate pollution from Cd and light pollution from Pb were observed both at the MS and ZX sites, whereas the MX site exhibited a pattern of heavy Cd pollution and light Cr and Pb pollution. In our study area, the results indicated that Cd exhibited a higher ecological risk than did the other heavy metals. Finally, the pH and nitrogen content of sediments may play a key role in controlling the amount of heavy metal bioavailability, further inducing a higher potential ecological risk.

Knowledge of vegetation dynamics in relation to climatic changes and human activities is essential for addressing the terrestrial carbon cycle in the context of global warming. Scientific detection and quantitative attribution of vegetation dynamic changes in different climatic zones and human activities are the focus and challenge of the relevant research. Taking the Poyang Lake basin as the research area, this study aimed to reveal how climate and land use drive changes in net primary productivity (NPP) in the subtropical humid basin. Change patterns of vegetation NPP and their relationships with meteorological factors across the basin were first investigated based on the estimation of 18 year (2000–2017 year) NPP by using a typical light energy utilization model, the Carnegie-Ames-Stanford Approach (CASA) model. Quantitative analysis was then conducted to explicitly distinguish the driving effects of climate change and land-use change on NPP dynamics in two different periods. Results show that annual NPP and total production (TP) of the Poyang Lake basin increased significantly from 2000 to 2017. During this period, land-use change in the basin was driven by the process of urbanization expansion and the efforts of ecological protection. Climatically, the temperature is the major influencing climatic factor in determining vegetation productivity in the subtropical humid basin, followed by precipitation and solar radiation. In addition, our investigation also revealed that with comparison to the period of 2000s, the increased TP of the Poyang Lake basin due to climate change in 2010s was much bigger than the decreased TP due to land-use change. However, in the areas where the land-use change occurred, the decreased TP was mainly attributed to the impact of land-use change, even though climate change showed a positive effect of increasing productivity.

The article presents a study on the properties of a mean square value featuring the dual function of Smarandache function, square value formula and prime divisor function through analytic method.

In the title mononuclear complex, [Cu(C14H10O3)(C12H8N2)(H2O)], the CuII atom is five-coordinated by two N atoms from a 1,10-phenanthroline (phen) ligand, two O atoms from a benzilate ligand and one O atom from a water molecule in a distorted square-pyramidal geometry. The crystal structure is stabilized via intermolecular O—H...O and C—H...O hydrogen bonds, C—H...π interactions and π–π stacking interactions between the pyridine and benzene rings of neighboring phen ligands [centroid–centroid distances = 3.684 (2), 3.564 (2) and 3.380 (1) Å].