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Translation is regulated mainly in the initiation step, and its dysregulation is implicated in many human diseases. Several proteins have been found to regulate translational initiation, including Pdcd4 (programmed cell death gene 4). Pdcd4 is a tumor suppressor protein that prevents cell growth, invasion, and metastasis. It is downregulated in most tumor cells, while global translation in the cell is upregulated. To understand the mechanisms underlying translational control by Pdcd4, we used single-particle cryo-electron microscopy to determine the structure of human Pdcd4 bound to 40S small ribosomal subunit, including Pdcd4-40S and Pdcd4-40S-eIF4A-eIF3-eIF1 complexes. The structures reveal the binding site of Pdcd4 at the mRNA entry site in the 40S, where the C-terminal domain (CTD) interacts with eIF4A at the mRNA entry site, while the N-terminal domain (NTD) is inserted into the mRNA channel and decoding site. The structures, together with quantitative binding and in vitro translation assays, shed light on the critical role of the NTD for the recruitment of Pdcd4 to the ribosomal complex and suggest a model whereby Pdcd4 blocks the eIF4F-independent role of eIF4A during recruitment and scanning of the 5' UTR of mRNA.

This study focuses on what latecomers can leverage to drive their learning; moreover, it examines how domestic customer demands and latecomers' internal capabilities affect their preferences for external technology acquisition. Using a policy-capturing technique, this study shows that customer demand and latecomers' absorptive capacity are positively related to their preferences for technology purchase and imitation. R&D capabilities negatively affect latecomers' preferences for technology purchase. Furthermore, customer demand allows latecomers to prefer technology purchase over technology imitation; absorptive capacity drives latecomer preferences for technology imitation over technology purchase; and latecomers with high R&D capabilities are more inclined to 'NOT purchase' rather than 'NOT imitation'. [ABSTRACT FROM AUTHOR]

In order to study the chemical characteristics and ion source of groundwater and support pollution control and prevention, as well as the rational development and utilization of groundwater resources in Baotou City, 33 groups of groundwater samples were collected from the western area of Kundulun River in Baotou. Piper diagram, Gibbs diagram, ion ratio, and multivariate statistical analysis methods were comprehensively used to analyze the hydrochemical characteristics, ion source and formation mechanism of groundwater. The results showed that the groundwater in the study area was neutral-weak alkaline water, TH was high, and the TDS was between 116~6 032 mg/L, the anions and cations were dominated by SO42-, HCO3- and Na+, Ca2+, Mg2+, and the content of ions in phreatic water was more than that in confined water. The hydrochemistry types of groundwater were complex, the types of anions and cations were dominated by SO4 • Cl, HCO3 • SO4 • Cl, HCO3 and Na•Ca•Mg, Ca•Mg. The chemical components of groundwater were mainly affected by rock weathering leaching and evaporation concentration, followed by cation alternating adsorption and human activities, TDS, total hardness, Ca2+, Mg2+ were mainly derived from the dissolution of silicate rocks and evaporite rocks, K+, Cl-, SO42- were mainly derived from the industrial and mining activities, HCO3-, NO3- were mainly derived from the weathering of carbonate rock and agricultural activities, Na+ were mainly derived from the rock weathering and industrial and mining activities. [ABSTRACT FROM AUTHOR]

This study has thoroughly uncovered the characteristics of the marine euphotic zone system in the Beibu Gulf, featuring adjacent semiconducting minerals and electrochemically active microbes, via mineralogical characterization, photoelectrochemical measurements, and microbiological analysis techniques. Notably, results of Raman and ESEM with EDS indicated that anatase, the semiconducting mineral with prominent photocatalytic performance, exists in large quantities in the Beibu Gulf. Photoelectrochemical measurements tested photoelectric response and redox activity of suspended particulate minerals, demonstrating the suspended particulates dominated by titanium and iron oxide semiconducting minerals presented excellent photo-response property and distinct photoelectric catalytic potential under visible light irradiation. Its significant property of photoelectric response with 110.483% increment ratio of the average photocurrent density relative to the dark current density. 16S amplicon sequence analysis revealed that the euphotic zone was dominated by Proteobacteria, Actinobacteria, and Cyanobacteria at the phylum level, and by Synechococcus CC9902, Cyanobium PCC-6307 and unclassified Ilumatobacteraceae at the genus level. Halomonas (0.2–1.2%), Vibrio (0.7–1.8%), and Nautella (0.1–1.1%), closely related to semiconducting minerals reduction reaction, were also presented in YL and RGS samples of the Beibu Gulf. This work firstly revealed that the neglected characteristics of the marine euphotic zone system in the Beibu Gulf of the South China Sea, which is an important natural ecosystem for microorganisms to uptake energy sources. It will provide a new perspective for further research on novel ways for microorganisms to acquire energy sources through semiconducting minerals in the marine euphotic zone system. [ABSTRACT FROM AUTHOR]