Phosphate-solubilizing bacteria (PSB) have the ability to dissolve insoluble phosphate and enhance soil fertility. However, the growth and mineral phosphate solubilization of PSB could be affected by exogenous soluble phosphate and the mechanism has not been fully understood. In the present study, the growth and mineral phosphate-solubilizing characteristics of PSB strain WS-FJ9 were investigated at six levels of exogenous soluble phosphate (0, 0.5, 1, 5, 10, and 20 mM). The WS-FJ9 strain showed better growth at high levels of soluble phosphate. The phosphate-solubilizing activity of WS-FJ9 was reduced as the soluble phosphate concentration increased, as well as the production of pyruvic acid. Transcriptome profiling of WS-FJ9 at three levels of exogenous soluble phosphate (0, 5, and 20 mM) identified 446 differentially expressed genes, among which 44 genes were continuously up-regulated when soluble phosphate concentration was increased and 81 genes were continuously down-regulated. Some genes related to cell growth were continuously up-regulated, which would account for the better growth of WS-FJ9 at high levels of soluble phosphate. Genes involved in glucose metabolism, including glycerate kinase, 2-oxoglutarate dehydrogenase, and sugar ABC-type transporter, were continuously down-regulated, which indicates that metabolic channeling of glucose towards the phosphorylative pathway was negatively regulated by soluble phosphate. These findings represent an important first step in understanding the molecular mechanisms of soluble phosphate effects on the growth and mineral phosphate solubilization of PSB.

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An experiment was conducted in a 20-level building to study the individual ascent speed on long stair. 165 college students, including 51 female students and 114 male students, took part in the experiment. Their ascent speeds and heart rates were recorded during they traveled upward. The experimental results show that their ascent speeds decrease continuously for the first 13-14 levels, then the ascent speeds keep at around 0.68 m/s for the males and 0.52 m/s for the females. Further study was conducted to explore the factors that might affect the ascent speeds on long stair. For the males, their ascent speeds show no obvious correlation with their body mass index and their scores of physical fitness test. For the females, it is observed that those who are overweight or fail in physical fitness test have the lowest ascent speed. After traveling upward around 18 levels, the average heart rates increase to 135 bpm and the average relative heart rates increase to 60% for the males, while the average heart rates increase to 150 bpm and the average relative heart rates increase to 70% for the females. Moreover, participates are more likely to use handrail for assistance as they move upward on higher levels.

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Two-dimensional layered materials have attracted tremendous attention as photodetectors due to their fascinating features, including comprehensive coverage of band gaps, high potential in new-generation electronic devices, mechanical flexibility, and sensitive light–mass interaction. Currently, graphene and transition-metal dichalcogenides (TMDCs) are the most attractive active materials for constructing photodetectors. A growing number of emerging TMDCs applied in photodetectors bring up opportunities in the direct band gap independence with thickness. This study demonstrated for the first time a photodetector based on a few-layer Re x Mo1–x S2, which was grown by chemical vapor deposition (CVD) under atmospheric pressure. The detailed material characterizations were performed using Raman spectroscopy, photoluminescence, and X-ray photoelectron spectroscopy (XPS) on an as-grown few-layer Re x Mo1–x S2. The results show that both MoS2 and ReS2 peaks appear in the Re x Mo1–x S2 Raman diagram. Re x Mo1–x S2 is observed to emit light at a wavelength of 716.8 nm. The electronic band structure of the few layers of Re x Mo1–x S2 calculated using the first-principles theory suggests that the band gap of Re x Mo1–x S2 is larger than that of ReS2 and smaller than that of MoS2, which is consistent with the photoluminescence results. The thermal stability of the few layers of Re x Mo1–x S2 was evaluated using Raman temperature measurements. It is found that the thermal stability of Re x Mo1–x S2 is close to those of pure ReS2 and MoS2. The fabricated Re x Mo1–x S2 photodetector shows a high response rate of 7.46 A W–1 under 365 nm illumination, offering a competitive performance to the devices based on TMDCs and graphenes. This study unambiguously distinguishes Re x Mo1–x S2 as a future candidate in electronics and optoelectronics.