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  • Article
    Gavish Y, Ziv Y.
    PLoS One. 2016;11(12):e0168417.
    Understanding the main processes that affect community similarity have been the focus of much ecological research. However, the relative effects of environmental and spatial aspects in structuring ecological communities is still unresolved and is probably scale-dependent. Here, we examine the effect of habitat identity and spatial distance on fine-grained community similarity within a biogeographic transition zone. We compared four hypotheses: i) habitat identity alone, ii) spatial proximity alone, iii) non-interactive effects of both habitat identity and spatial proximity, and iv) interactive effect of habitat identity and spatial proximity. We explored these hypotheses for spiders in three fragmented landscapes located along the sharp climatic gradient of Southern Judea Lowlands (SJL), Israel. We sampled 14,854 spiders (from 199 species or morphospecies) in 644 samples, taken in 35 patches and stratified to nine different habitats. We calculated the Bray-Curtis similarity between all samples-pairs. We divided the pairwise values to four functional distance categories (same patch, different patches from the same landscape, adjacent landscapes and distant landscapes) and two habitat categories (same or different habitats) and compared them using non-parametric MANOVA. A significant interaction between habitat identity and spatial distance was found, such that the difference in mean similarity between same-habitat pairs and different-habitat pairs decreases with spatial distance. Additionally, community similarity decayed with spatial distance. Furthermore, at all distances, same-habitat pairs had higher similarity than different-habitats pairs. Our results support the fourth hypothesis of interactive effect of habitat identity and spatial proximity. We suggest that the environmental complexity of habitats or increased habitat specificity of species near the edge of their distribution range may explain this pattern. Thus, in transitions zones care should be taken when using habitats as surrogate of community composition in conservation planning since similar habitats in different locations are more likely to support different communities.
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  • Article
    Ren G, Chen L, Fan J, Hou S, Chen J, Deng H, Luo J, Huang P, Zhao Y, Li J, Feng D, Ge C, Yu H.
    Sci Total Environ. 2024 Jan 15;908:168417.
    Since data on Per- and polyfluoroalkyl substances (PFASs) in mangrove ecosystems are very limited. This study investigated the occurrence, distribution, sources, and ecological risk of 24 PFASs in the overlying waters and sediments of mangrove systems in Hainan Island, China. The concentration levels of PFASs in water and sediment ranged from 6.3 to 35.3 ng/L and from 0.33 to 10.2 ng/g dw, respectively. In terms of spatial distribution, firstly, the mangrove forests in Haikou and Sanya contained higher levels of PFASs; secondly, the eastern region contained higher levels of PFASs than the western region. The reasons for this may be related to the population size and development level of the region. For the organic carbon normalized sediment-water partition coefficient (log Koc), the results showed that log Koc decreased with increasing carbon chains for short-chain PFASs (with ≤6 CF2 units) and increased with increasing carbon chains for long-chain PFASs (with ˃6 CF2 units). Principal Component Analysis (PCA) and correlation analysis were employed to pinpoint specific origins of PFASs, namely firefighting, metal plating, food packaging, textiles, and fluoropolymer manufacturing. The risk quotient (RQ) values of PFASs in mangrove ecosystems on Hainan Island were all <1, but the existence of potential risks cannot be excluded. Hence, further investigations related to the bioaccumulation effects of PFASs in organisms in mangrove forests should be conducted to gain a more comprehensive understanding of their environmental behavior.
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  • Article
    Bozděchová L, Havlová K, Fajkus P, Fajkus J.
    J Mol Biol. 2024 02 15;436(4):168417.
    Telomerase RNA (TR) conformation determines its function as a template for telomere synthesis and as a scaffold for the assembly of the telomerase nucleoprotein complex. Experimental analyses of TR secondary structure using DMS-Map Seq and SHAPE-Map Seq techniques show its CLOSED conformation as the consensus structure where the template region cannot perform its function. Our data show that the apparent discrepancy between experimental results and predicted TR functional conformation, mostly ignored in published studies, can be explained using data analysis based on single-molecule structure prediction from individual sequencing reads by the recently established DaVinci method. This method results in several clusters of secondary structures reflecting the structural dynamics of TR, possibly related to its multiple functional states. Interestingly, the presumed active (OPEN) conformation of TR corresponds to a minor fraction of TR under in vivo conditions. Therefore, structural polymorphism and dynamic TR transitions between CLOSED and OPEN conformations may be involved in telomerase activity regulation as a switch that functions independently of total TR transcript levels.
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  • Book
    Steven F. Weiner, Christopher C. Surek.
    Summary: An anatomically-informed guide on the use of ultrasound to elevate facial rejuvenation outcomes. Facial injection requires in-depth understanding of clinically relevant underlying anatomy. Until the recent introduction of ultrasound into the medical aesthetics space, soft tissue filler and neurotoxin injection relied upon the injector's experience and ability to navigate the face without direct vision of deeper structures. Atlas of Ultrasound and Anatomy: Facial Rejuvenation by internationally renowned facial rejuvenation experts Steven F. Weiner and Christopher C. Surek provides a high-yield anatomical guide on how to leverage ultrasound to optimize facial injection results. This unique textbook is the culmination of hundreds of cadaver dissections, extensive literature reviews, and countless ultrasound images. Throughout four chapters, the authors share a wealth of knowledge garnered from decades of surgical and injection experience. The first chapter discusses how anatomical concepts can be applied to the various aesthetic subunits of the face to navigate desired targets and avoid potential danger zones. Chapters two through four present an immersive journey through layered anatomy of the upper, middle, and lower face, respectively, and the use of ultrasound to finesse techniques. Key Features: Clinically relevant anatomy highlighting different facial layers and the symphony of structures that exist within them; Step-by-step guidance for utilizing ultrasound to prevent facial injection complications and improve patient outcomes; Beautiful medical illustrations and ultrasound images provide high-yield insights; This is an essential reference for facial injectors to sharpen their skills and perform precision facial rejuvenation procedures informed by ultrasound imagery. - Provided by publisher.
doi:10.1371/journal.pone.0168417 doi:10.1016/j.scitotenv.2023.168417 doi:10.1016/j.jmb.2023.168417