[Analysis of Spatiotemporal Variation Characteristics and Driving Forces of NPP in Shanxi Province from 2000 to 2020 Based on Geodetector].

The net primary productivity (NPP) of vegetation, as an indispensable element in carbon cycle studies, characterizes plant growth status. This study applied MODIS NPP products from 2000 to 2020 and multi-source data on elevation, slope, precipitation, temperature, land use, and population density in Shanxi province. We used trend analysis, correlation analysis, and geographic probes to explore the spatial and temporal evolution characteristics and driving factors of NPP in Shanxi province and its national planned coal-mining areas.

[Comparison of the influences of gold alloy metal crown and ni-cr alloy metal crown on gingival health].

Objective: To compare the influences of gold alloy metal crown and Ni-Cr alloy metal crown on gingival health.

Methods: Totally 20 patients requiring one metal crown restoration were divided into the gold alloy metal crown group (n=9) and Ni-Cr alloy metal crown group (n=11). The contra-lateral homonymy natural healthy teeth served as controls.