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[Objective] The characteristics of sand and dust transport amount and particle size on the windward and leeward sides of a natural Populus euphratica riparian forest at the Arghan section of the lower reaches of the Tarim River under the prevailing wind direction were studied in order to provide a theoretical basis for its windbreak and sand fixation capacity. [Methods] Sediments were collected from two windward sites (Y1 and Y2) and two leeward sites (B1 and B2) of the forest at five heights of 10, 30, 50, 100, and 150 cm near the surface using a BSNE sand collector. The particle size characteristics of the sand samples were then measured using a Microtrac S3500 laser diffraction particle size analyzer. [Results] ① The horizontal flux of sand and dust in the four sample plots followed either a power function or exponential function distribution, and total sediment transport followed the order of Y1 > Y2 > B1 > B2. The sediment transport for each sample plot decreased with increasing height from the soil surface. ② The reduction of sediment on the leeward side compared with the windward side ranged from 35% to 80% less than on the windward side, indicating that the natural P. euphratica riparian forest in the lower reaches of the Tarim River has obvious windbreak and sand fixation benefits. ③ The average particle size of sand grains at all heights was 80~93 μm, mainly composed of extremely fine sand. The particle size frequency curve showed a single peak distribution, and the sand dust composition was simple, mainly composed of local sand sources. [Conclusion] The sediment transport on the leeward side of the natural P. euphratica riparian forest in the study area was lower than that of the windward side. Average particle size was smaller and sorting performance was better on the leeward side than on windward side. The average particle size smaller than that of the windward side, the sorting was better than that of the windward side, the kurtosis was narrower than that of windward side, and skewness is slightly smaller than that of the windward side. The P. euphratica riparian forest exhibited obvious windbreak and sand fixation benefits, and can be used as an effective measure to reduce the damage by wind and sand transport in the study area.

As one of the most serious health issues facing trees, the occurrence of decay and hollowing not only reduces the stability and quality of living trees but also leads to the deterioration of their eco-physiological functions, which creates great challenges to the conservation and sustainable management of forest resources. In recent years, the study of tree decay and hollow rot have attracted more and more attention from scholars at home and abroad. The relevant research results have a great significance for the prevention and control of affected living trees and the conservation and sustainable management of endangered species. However, there is a lack of systematic literature review and an insufficient understanding of research hotspots and trends in this field. This paper selects literature retrieved from the CNKI and Web of Science core databases as data sources, the number of publications, research topics, research status, hot spots, and trends, as well as the main research countries, institutions, and co-cited authors in the field of tree decay are visualized by using bibliometrics software CiteSpace (V.5.8.R3), and the current international research hotspots and development trends in this field were systematically summarized. The results showed that the number of papers in this field at home and abroad showed rapid growth in general, and the number of Chinese papers showed a slow growth after 2009. The number of papers published in English by Chinese authors was more than the number of papers published in Chinese in the field. From 2002 to 2021, the research hotspots in this field are constantly changing. Cluster analysis shows that the main themes of the relevant research are as follows: "Eastern Canada" tree species, "hydraulic vulnerability segmentation", "dead wood management", and "hydraulic safety". The advantages and disadvantages of hollow/dead wood on forest ecosystems were explored from different perspectives, providing a theoretical basis and scientific support for the forest health and sustainable management. The United States dominates the research in this field, while China is a relatively late comer but is catching up fast, and the Chinese Academy of Sciences is the most prolific publisher on this topic in China. The influence of Chinese research in this field on relevant international publications is gradually increasing. In short, the research in this field is still in the phase of rapid development, and both the breadth and depth of quantitative research are increasing. How to accurately diagnose and quantify the internal decay of tree trunks and its relationship with tree death and forest decline under the interference and pressure of climate change and human activities is still a hot and difficult issue in this field. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) modified by luminescent Ru(ii) complexes not only possess bright red fluorescence but also can target lysosomes. Cell imaging and a cytotoxicity study suggest that Ru1–2·AgNPs may act as a potential theranostic agent. [ABSTRACT FROM AUTHOR]

Chiral recognition of DNA molecules is important because much evidence has indicated that transformations of chirality and diverse conformations of DNA are involved in a series of key biological events. Among these, enrichment of G-quadruplexes (GQs) in the genome, and the exploration of their multiple structures, has aroused great interest. Herein, we compared nearly 100 different sequences with 3′-tail sequences of variable length or different linkers or diverse loops and mutative ionic concentrations. All sequences were capable of forming stable GQs, with fluorescence signal enhancement upon binding with Δ- and Λ- [Ru(bpy)2(dppz-idzo)]2+ (Δ/Λ-1). Our results show that multiple factors, including the 3′-tail length, linkers, loop length and ionic concentration, regulate the enantioselectivity of GQs. Furthermore, molecular docking simulations revealed that chiral recognition of GQs depends on the binding site. To the best of our knowledge, this is the first systematic study regarding the regulation of multi-factors for GQ selectivity of chiral Ru-complexes. These results will serve as a useful reference for enantioselective recognition of genomic GQs and may facilitate the development of chiral anticancer agents for targeting GQs. [ABSTRACT FROM AUTHOR]

Chiral recognition of DNA molecules is important because much evidence has indicated that transformations of chirality and diverse conformations of DNA are involved in a series of key biological events. Among these, enrichment of G-quadruplexes (GQs) in the genome, and the exploration of their multiple structures, has aroused great interest. Herein, we compared nearly 100 different sequences with 3′-tail sequences of variable length or different linkers or diverse loops and mutative ionic concentrations. All sequences were capable of forming stable GQs, with fluorescence signal enhancement upon binding with Δ- and Λ- [Ru(bpy)2(dppz-idzo)]2+ (Δ/Λ-1). Our results show that multiple factors, including the 3′-tail length, linkers, loop length and ionic concentration, regulate the enantioselectivity of GQs. Furthermore, molecular docking simulations revealed that chiral recognition of GQs depends on the binding site. To the best of our knowledge, this is the first systematic study regarding the regulation of multi-factors for GQ selectivity of chiral Ru-complexes. These results will serve as a useful reference for enantioselective recognition of genomic GQs and may facilitate the development of chiral anticancer agents for targeting GQs. [ABSTRACT FROM AUTHOR]

Chiral recognition of DNA molecules is important because much evidence has indicated that transformations of chirality and diverse conformations of DNA are involved in a series of key biological events. Among these, enrichment of G-quadruplexes (GQs) in the genome, and the exploration of their multiple structures, has aroused great interest. Herein, we compared nearly 100 different sequences with 3'-tail sequences of variable length or different linkers or diverse loops and mutative ionic concentrations. All sequences were capable of forming stable GQs, with fluorescence signal enhancement upon binding with Δ- and Λ- [Ru(bpy)2(dppz-idzo)]2+ (Δ/Λ-1). Our results show that multiple factors, including the 3'-tail length, linkers, loop length and ionic concentration, regulate the enantioselectivity of GQs. Furthermore, molecular docking simulations revealed that chiral recognition of GQs depends on the binding site. To the best of our knowledge, this is the first systematic study regarding the regulation of multi-factors for GQ selectivity of chiral Ru-complexes. These results will serve as a useful reference for enantioselective recognition of genomic GQs and may facilitate the development of chiral anticancer agents for targeting GQs.