•A five-step framework was proposed to conduct construction safety research review.•Topics were grouped into the process, individual/group features, and accident data.•The first group is studied from ...the aspect of safety management process.•The second group aims to explore the impact of individual/group features on safety.•The third group focuses on utilizing accident data to improve safety performance.
Persistent endeavors have been made to promote construction safety, but fatalities still plague the industry. Recently there had been an emergence of a variety of construction safety research focusing on topics such as safety competency, accident statistics, design for safety, and safety culture. A large number of construction safety studies with the variety of topics make it difficult for stakeholders to have an overview of this field. Hence a systematic review of previous studies is paramount for facilitating sharing useful research findings and accessing future trends in construction safety research. A five-step framework was proposed in this review. The analysis focused on publication year, journal title, country/region distribution, organizational level, project phase, project type, innovative technology application and research topic. Three groups of construction safety research were identified. The first group of research is conducted from the perspective of safety management process, such as safety assessment and safety program. The second group aims to explore the impact of individual and group characteristics in relation to construction safety, such as worker behavior, perception, and safety climate. The third group utilizes accident/incident data to improve safety performance. In order to better capture construction safety research trend, these studies were discussed from chronological and thematic perspectives. Four main research findings including construction safety research perspectives, construction safety research trends, innovative technology applications in construction safety, and safety information flow, were gained. Finally, this review identified and discussed research gaps and corresponding agenda which can serve as guidance for future construction safety research.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Codon usage biases are found in all eukaryotic and prokaryotic genomes, and preferred codons are more frequently used in highly expressed genes. The effects of codon usage on gene expression were ...previously thought to be mainly mediated by its impacts on translation. Here, we show that codon usage strongly correlates with both protein and mRNA levels genome-wide in the filamentous fungus Neurospora. Gene codon optimization also results in strong up-regulation of protein and RNA levels, suggesting that codon usage is an important determinant of gene expression. Surprisingly, we found that the impact of codon usage on gene expression results mainly from effects on transcription and is largely independent of mRNA translation and mRNA stability. Furthermore, we show that histone H3 lysine 9 trimethylation is one of the mechanisms responsible for the codon usage-mediated transcriptional silencing of some genes with nonoptimal codons. Together, these results uncovered an unexpected important role of codon usage in ORF sequences in determining transcription levels and suggest that codon biases are an adaptation of protein coding sequences to both transcription and translation machineries. Therefore, synonymous codons not only specify protein sequences and translation dynamics, but also help determine gene expression levels.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
The article is devoted to topical issues of creating pedagogical conditions for learning to play the saxophone in distant format. The relevance of the research topic is due to the fact that during ...the period of quarantine on COVID-19 pandemic, education in music universities required new teaching methods and new pedagogical conditions. The research materials were the valuation results of pedagogical observation in two groups of 1st year students of the music university. The general sample of students was 150 people. The representative sample was 50 people selected by mechanical sampling. Two groups of 15 students, participated in the experimental sessions, and one control group were selected. The material was collected with author’s methodology, conditioned by the research logic and objectives. The empirical study was carried out in three stages. The research methodology was based on a systematic approach and includes the methods of the general scientific group (analysis, synthesis, induction, deduction); as well as special methods: content analysis of scientific literature, the method of included pedagogical observation, statistical analysis. As a result of the study, the author came to the following conclusions: in order to improve the level of professional skills of playing the saxophone among 1st year students, it is important to create special pedagogical conditions in the distance learning format (the use of multimedia, digital and communication technologies, collective music-making online and individual work based on online classes).
Codon usage bias is a universal feature of eukaryotic and prokaryotic genomes and has been proposed to regulate translation efficiency, accuracy, and protein folding based on the assumption that ...codon usage affects translation dynamics. The roles of codon usage in translation, however, are not clear and have been challenged by recent ribosome profiling studies. Here we used a Neurospora cell-free translation system to directly monitor the velocity of mRNA translation. We demonstrated that the preferred codons enhance the rate of translation elongation, whereas non-optimal codons slow elongation. Codon usage also controls ribosome traffic on mRNA. These conclusions were supported by ribosome profiling results in vitro and in vivo with template mRNAs designed to increase the signal-to-noise ratio. Finally, we demonstrate that codon usage regulates protein function by affecting co-translational protein folding. These results resolve a long-standing fundamental question and suggest the existence of a codon usage code for protein folding.
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•The velocity of mRNA translation is monitored using a cell-free system•Preferred codons enhance the elongation rate, whereas non-optimal codons reduce it•Ribosome profiling results confirm the role of codon usage in elongation•Codon usage regulates protein function by affecting co-translational protein folding
Yu et al. demonstrate that codon usage impacts local translational dynamics: frequently used codons speed up elongation, while non-preferred codons slow it down. The changes of translation elongation rates on mRNAs are adapted to protein structures to facilitate co-translational folding. The results suggest a codon usage “code” for protein structure.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The discovery of natural adhesion phenomena and mechanisms has advanced the development of a new generation of tissue adhesives in recent decades. In this study, we develop a natural biological ...adhesive from snail mucus gel, which consists a network of positively charged protein and polyanionic glycosaminoglycan. The malleable bulk adhesive matrix can adhere to wet tissue through multiple interactions. The biomaterial exhibits excellent haemostatic activity, biocompatibility and biodegradability, and it is effective in accelerating the healing of full-thickness skin wounds in both normal and diabetic male rats. Further mechanistic study shows it effectively promotes the polarization of macrophages towards the anti-inflammatory phenotype, alleviates inflammation in chronic wounds, and significantly improves epithelial regeneration and angiogenesis. Its abundant heparin-like glycosaminoglycan component is the main active ingredient. These findings provide theoretical and material insights into bio-inspired tissue adhesives and bioengineered scaffold designs.
Additive manufacturing is an advanced forming method to fabricate complex components, while cracks appear in the deposited nickel-based single crystal superalloy samples undesirably. Though ...fabrication of crack-free superalloy were reported, effective solutions to fabricate crack-free nickel-based single crystal superalloy samples are still uncovered, thus the additive manufacturing in single crystal superalloy is still an extremely difficult work. In this work, we fabricated nickel-based single crystal superalloy samples through laser powder deposition, and analyzed the causes of crack during deposition processing. Experimental results demonstrate that the as-deposited thin-wall samples presented single crystal structure and its crystal orientation is well aligned with the 001 orientation of substrate, while some cracks appeared in the as-deposited block samples. Large misorientation angle in the local regions played significant roles in the cracks initiation and the further cracking propagation. Solidification cracks are attributed to the shrinkage cavities and the high-melting point interdendritic carbides, while liquation cracks are attributed to the low melting point compounds. These findings give a guide for causes analysis on cracks in the nickel-based single crystal superalloy fabricated by laser powder deposition additive manufacturing, which has bright prospects in single crystal superalloy manufacturing and repair.
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•Nickel-based single crystal superalloy samples were fabricated through laser powder deposition.•Large misorientation angle played significant roles in the cracks initiation and the further cracking propagation.•These findings give a guide for causes analysis on cracks in the nickel-based single crystal superalloy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The improvement of the impact resistance of carbon fiber reinforced epoxy (CF/EP) composite is of great significance for its application in safety protection. Herein, an approach to improve the ...compressive mechanical properties of CF/EP composites by self-interlocking Ti3C2Tx/polyvinyl alcohol (PVA) aerogel (TPA) has been developed. Mechanical responses and strain rate effects of CF/EP and TPA/CF/EP composites in longitudinal, transverse and through-thickness directions under quasi-static/dynamic loading have been studied. The results show that the stitching effect of TPA leads to the fact that the fracture has been dominated by cohesive failure and fiber breakage. Compared with CF/EP composites, TPA/CF/EP composites exhibit higher compressive strength and Young's modulus in the strain rate range from 0.003 s−1 to 2369 s−1. TPA/CF/EP composites have different damage evolution under quasi-static and dynamic loading and exhibits obvious strain rate sensitivity. Moreover, high-speed camera photographs and micro-morphological characteristics show that TPA/CF/EP laminates have different failure modes and fracture mechanisms for different loading directions. The well understanding of fracture mechanism can strengthen people's capability of and offer insights into designing advanced energy-absorbing materials and structures.
•A self-interlocked network using Ti3C2Tx/PVA aerogel (TPA) is constructed.•TPA can significantly improve impact resistance of CF/EP composites.•Mechanical responses under different loading directions are analyzed.•TPA can effectively limit the delamination failure between fiber and matrix.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Earthquakes are a consequence of the motions of the planet's tectonic plates, yet predicting when and where they may occur, and how to prepare remain some of the shortcomings of using scientific ...knowledge to protect human life. A devastating Mw 7.0 earthquake on October 30, 2020, offshore Samos Island, Greece was a consequence of the Aegean and Anatolian upper crust being pulled apart by north-south extensional stresses resulting from slab rollback, where the African plate is subducting northwards beneath Eurasia, while the slab is sinking by gravitational forces, causing it to retreat southwards. Since the retreating African slab is coupled with the overriding plate, it tears the upper plate apart as it retreats, breaking it into numerous small plates with frequent earthquakes along their boundaries. Historical earthquake swarms and deformation of the upper plate in the Aegean have been associated with massive volcanism and cataclysmic devastation, such as the Mw 7.7 Amorgos earthquake in July 1956 between the islands of Naxos and Santorini (Thera). Even more notable was the eruption of Santorini 3650 years ago, which contributed to the fall of the Minoan civilization. The Samos earthquake highlights the long historical lack of appreciation of links between deep tectonic processes and upper crustal deformation and geological hazards, and is a harbinger of future earthquakes and volcanic eruptions, establishing a basis for studies to institute better protection of infrastructure and upper plate cultures in the region.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•The unweighted directed network subway construction accident network (SCAN) is integrated with 26 vertices and 49 edges.•Pajek 3.08 was employed to assist in identifying SCAN and analyzing ...corresponding topological parameters.•If vertices with high degree are attacked simultaneously, SCAN will be vulnerable and turned into isolated sub-networks.•SCAN obeys small-world properties, exhibiting much faster accident propagation than a regular network.
Accident case analysis has been widely adopted to promote construction safety. Learning from past accidents is effective to avoid similar dangerous situations or accidents. An accident is often the result of a sequence of previous accidents, or the cause of the next accidents. There is an accident chain or network in practice. Instead of analyzing a single accident, this study uses network theory to explore the complexity of the subway construction accident network (SCAN). Pajek was employed to identify SCAN and analyze corresponding topological characteristics. As a result, an unweighted directed network with 26 vertices and 49 edges was obtained. Five parameters were calculated for better capturing the structure of SCAN. The cumulative degree distribution obeys power-law distribution. This indicates that SCAN is resilience to random attacks. If some high-degree vertices are attacked at the same instant, SCAN is turned to be vulnerable and isolated. The characteristics of big clustering coefficient and short average path length denote that SCAN is a small-world network. This type of network demonstrates faster accident propagation than regular networks. Almost 60% of shortest paths contain collapse of soil, struck-by, explosion and collapse of machine. Effectively controlling these four types of accidents can increase average path length and diameter. As a result, accident propagation efficiency can lower, and chain reaction is dampened in this accident network. Topological parameters analysis is beneficial to understanding the mechanism and capturing the complexity of SCAN. It is helpful to restraint original accidents, and prevent secondary and derivative accidents, which can assist in improving safety management on subway construction sites.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Hepatoblastoma (HB) is a common liver malignancy in children. Our previous study has disclosed the crucial role of STAT3 (signal transducer and activator of transcription 3) in HB.
Present study was ...designed to study the circular RNA (circRNA) STAT3 in HB.
Gel electrophoresis revealed the circular characteristics of circ-STAT3. Function assays like EdU, transwell and sphere formation assay disclosed the function of circ-STAT3 in HB cells. Mechanism assays including ChIP, RIP, RNA pull down assay demonstrated the macular mechanism underlying circ-STAT3.
Circ_0043800, which was originated from STAT3, was up-regulated in HB tissues and cells. More importantly, silencing of circ-STAT3 led to the inhibition on HB cell growth, migration and stem-cell characteristics. Circ_0043800 was predominantly located in the cytoplasm of HB cells. Then, circ_0043800 was found to up-regulate STAT3 via sponging miR-29a/b/c-3p. Besides, we identified that STAT3 overexpression partially rescued silenced circ_0043800, while miR-29a/b/c-3p inhibition completely rescued silenced circ_0043800 on HB cellular biological behaviors. Subsequently, Gli2 (GLI family zinc finger 2) was identified as another target of miR-29a/b/c-3p. Circ_0043800 served as a competing endogenous RNA (ceRNA) to up-regulate both Gli2 and STAT3 via sponging miR-29a/b/c-3p. Moreover, we figured out that Gli2 overexpression completely rescued silenced circ_0043800 on HB cell malignant behaviors. After that, we discovered that Gli2 transcriptionally activated circ_0043800. The in-vivo assays further revealed that circ_0043800 promoted HB tumor growth by up-regulation of Gli2 and STAT3.
Gli2-induced circ_0043800 served as the ceRNA to promote HB by up-regulation of STAT3 and Gli2 at a miR-29a/b/c-3p dependent manner.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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