Scale or effectiveness? The nonlinear impact of talent agglomeration on high-quality economic development in China.

Talent agglomeration serves as a vital pathway for achieving high-quality economic development. This paper, based on provincial panel data from China spanning 2011-2020, first analyses the impact of talent agglomeration on high-quality economic development from two dimensions: the talent agglomeration scale and effectiveness. Second, with innovation activity as a threshold variable, this paper explores the nonlinear impact of the talent agglomeration scale and effectiveness on economic efficiency improvement and economic structure optimization. This study finds that (1) the main driving force for high-quality economic development within the sample period comes from the talent agglomeration scale, while the promoting role of talent agglomeration effectiveness has not yet passed significant tests. (2) Under different levels of innovation activity, the talent agglomeration scale has a diminishing marginal utility impact on economic efficiency improvement and economic structure optimization; talent agglomeration effectiveness also has different nonlinear effects on economic efficiency improvement and economic structure optimization.

Optical Fiber Probe Microcantilever Sensor Based on Fabry-Perot Interferometer.

Optical fiber Fabry-Perot sensors have long been the focus of researchers in sensing applications because of their unique advantages, including highly effective, simple light path, low cost, compact size, and easy fabrication. Microcantilever-based devices have been extensively explored in chemical and biological fields while the interrogation methods are still a challenge. The optical fiber probe microcantilever sensor is constructed with a microcantilever beam on an optical fiber, which opens the door for highly sensitive, as well as convenient readout. In this review, we summarize a wide variety of optical fiber probe microcantilever sensors based on Fabry-Perot interferometer. The operation principle of the optical fiber probe microcantilever sensor is introduced. The fabrication methods, materials, and sensing applications of an optical fiber probe microcantilever sensor with different structures are discussed in detail. The performances of different kinds of fiber probe microcantilever sensors are compared. We also prospect the possible development direction of optical fiber microcantilever sensors.

High-Temperature Measurement of a Fiber Probe Sensor Based on the Michelson Interferometer.

In this paper, a fiber probe high-temperature sensor based on the Michelson Interferometer (MI) is proposed and experimentally verified. We used a fiber splicing machine to fabricate a taper of the single-mode fiber (SMF) end. The high order modes were excited at the taper, so that different modes were transmitted forward in the fiber and reflected by the end face of the fiber and then recoupled back to the fiber core to form MI. For comparison, we also coated a thin gold film on the fiber end to improve the reflectivity, and the reflection intensity was improved by 16 dB. The experimental results showed that the temperature sensitivity at 1506 nm was 80 pm/°C (100 °C~450 °C) and 109 pm/°C (450 °C~900 °C). The repeated heating and cooling processes showed that the MI structure had good stability at a temperature up to 900 °C. This fiber probe sensor has the advantages of a small size, simple structure, easy manufacturing, good stability, and broad application prospects in industrial and other environments.

Analysis of Metallo-ß-lactamases, oprD Mutation, and Multidrug Resistance of ß-lactam Antibiotic-Resistant Strains of Pseudomonas aeruginosa Isolated from Southern China.

The purpose of this study was to analyze the metallo-ß-lactamases (MBLs) genotype and oprD mutations of the ß-lactam antibiotic-resistant Pseudomonas aeruginosa (PA) strains isolated from southern China. We collected 110 strains of ß-lactam antibiotic-resistant PA from 2 hospitals during January 2016-December 2017 from Dongguan, South China. MBLs were detected, amplified, and typed using EDTA disc synergy test, PCR, and Sanger gene sequencing. The mutations and expression levels of oprD were detected using Sanger gene sequencing and qPCR. A total of 16.36% (18/110) ß-lactam antibiotic-resistant PA strains produced MBLs, and the main genotypes of MBLs were IMP-25, VIM-2, and SIM-2. Sanger gene sequencing results showed that 107 of the 110 strains harbored mutations in oprD sequence, while 3 strains were negative for oprD amplification (2.73%). Among the 107 strains with positive amplification (97.27%), the rate of intentional mutations (including deletions, insertions, and premature stop codons) was 93.46% (100/107) and that of no disrupted mutation was 6.54% (7/107). qPCR analysis confirmed that the expression level of the OprD protein in the 7 strains of no disrupted mutation was significantly reduced. Among the ß-lactam antibiotic-resistant PA strains in southern China, 16.36% were positive for MBLs. The loss rate of oprD was 2.73%, and almost all PA strains showed oprD amplification variation or transcription downregulation. Thus, impaired oprD expression and MBLs production may be some of the mechanisms of ß-lactam antibiotic-resistance of PA strains in southern China.