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Biotic exchanges between Taiwan and Mainland China have shaped the biodiversity and ecosystems of both regions. Exchanges from Mainland China to Taiwan have received more attention, mainly studied in terrestrial vertebrates, while the reverse direction and invertebrates have largely been overlooked. Here, we explore the dispersal events between these two regions based on the moths of three species groups of Obeidia, including Taiwan taxa and its relatives from mainland. We conducted mixed methods and analysis, including reconstructing a phylogenetic tree, estimating associated divergence times and inferring ancestral areas and source regions, to explore the phylogeographical structure and genetic pattern of three groups based on eight genes. Our results revealed a structure of three clades and every clade included at least one Taiwanese taxa and its closest relatives of mainland of China, and also served Taiwan as an important source region of two mainland taxa. Our study revealed various origin pattern and dispersal models on the basis of three species groups of Obeidia. Bi‐directional biotic exchange via a land bridge were found: four Taiwanese taxa originated from mainland, and two of them migrated back to mainland. Both eastern Himalayas and south China are important origin areas for Taiwan biota, and the dominant source region may need multiple insect cases to confirm. Our study also provided evidences for disjunct distribution from the perspective of insecta molecular phylogeny. [ABSTRACT FROM AUTHOR]

In repaired marine concrete structures, generally, an interface exists between old and new concrete, however, the influence of this interface on durability has yet not been well understood. In this study 18 reinforced concrete beams with new‐to‐old concrete interfaces (N–O interfaces) were designed to investigate chloride transport through a cracked interface. The effects of crack widths at the interface, concrete strain, and the chloride exposure time were considered, respectively. Results showed that the N–O interfaces having crack widths between 0 and 0.13 mm posed no significant impact on the chloride transport in the depth direction of the N–O interfaces, however when the crack width exceeded 0.13 mm, the chloride concentration gradually increased as the crack width increased. Chloride transport through the horizontal direction of the N–O interface was different between new and old concrete matrix when the crack width reached 0.18–0.20 mm. The surface layer with a range of 5–10 mm depth of concrete was sensitive to the variation of concrete strain, and the evolution of chloride concentration with concrete strain presented a logarithm relationship. Within the exposure period between 60 and 90 days, the increasing rate of chloride concentration was higher than that between 30 and 60 days. The study can provide some recommendations for repair of concrete elements exposed to a chloride‐laden exposure environment. [ABSTRACT FROM AUTHOR]

Globally, insect pollinators that are linked to increased yields in many crops have experienced severe population declines. Crop diversification is often proposed as an effective conservation measure to boost pollinator populations. Here, we investigate the potential benefits of mixed oilseed rape/milk vetch cultivation for wild pollinator communities by comparing it with oilseed rape monocultures. Studying 8 mixed and 10 monocropping fields positioned along a gradient of increasing semi‐natural habitat coverage in mountainous agricultural landscapes, we found that agricultural landscapes with mixed cultivation harboured higher wild pollinator diversity than oilseed rape monocropping landscapes. This positive effect was observed irrespective of the proportion of semi‐natural habitat. Meanwhile, the pollinator community composition in mixed cultivation landscapes was similar to that of oilseed rape monoculture landscapes, and, contrary to expectations, mixed cultivation did not benefit specific pollinator trait groups like cavity‐nesting bees. Overall, we believe the higher pollinator diversity linked to mixed cultivation can increase insect‐pollinated crop yields, and mixed oilseed rape‐milk vetch cultivation might represent a potential mitigation measure for the negative impacts agricultural intensification has on wild pollinator communities. [ABSTRACT FROM AUTHOR]

The full potential for using DNA barcodes for profiling functional trait diversity has yet to be determined in plants and animals; thus, we outline a general framework for quantifying functional trait diversity of insect community DNA and propose and assess the accuracy of three methods for achieving this. We built a novel dataset of traits and DNA barcodes for wild bees in China. An informatics framework was developed for phylogeny‐based integration of these data and prediction of traits for any subject barcodes, which was compared with two distance‐based methods. For Phylogenetic Assignment, we additionally conducted a species‐level analysis of publically available bee trait data. Under the specimen‐level dataset, the rate of trait assignment was negatively correlated with distance between the query and the nearest trait‐known reference, for all methods. Phylogenetic Assignment was found to perform best under several criteria; particularly, it had the lowest false‐positive rate (rarely returning a state prediction where success was unlikely; where the distance from query to the nearest reference was high). For a wider range of compiled traits, conservative life‐history traits showed the highest rates of assignment; for example, sociality was predicted with confidence at 53%, parasitism at 44% and nest location at 33%. As outlined herein, automated trait assignment might be applied at scale to either barcodes or metabarcodes. With further compilation and databasing of DNA barcode and trait data, the rate and accuracy of trait assignment is expected to increase to the point of being a widely viable and informative approach. [ABSTRACT FROM AUTHOR]

A novel quenching‐partitioning‐tempering (Q‐P‐T) process is applied to 60Si2Mn spring steel, resulting in multiphase microstructures consisting mainly of retained austenite (RA) and softened martensite (SFM). The influence of multiphase microstructures on the high‐cycle fatigue behavior of Q‐P‐T and traditional quenching and tempering (Q&T) spring steels are investigated under rotating–bending and tension–tension loading. The results indicate that the fatigue strength of Q‐P‐T spring steel with RA, SFM, and lower quenching stress increases by 23.9 and 14.4% under cyclic rotating–bending and tension–tension loadings, respectively, compared with that of Q&T spring steel. Under both loading modes, the fatigue crack of the Q‐P‐T spring steel is mainly initiated from the interface between the martensitic matrix and inclusions or carbides. In contrast, the fatigue crack of the Q&T spring steel is mainly initiated from the plastic area around the martensitic matrix rather than inclusions. The RA, SFM, and lower quenching stress of the Q‐P‐T spring steel are conducive to the formation of dimples and tear ridges in the crack propagation and ultimate failure areas, whereas the inadequate SFM and higher quenching stress of the Q&T spring steel are prone to the formation of quasi‐cleavage facets and secondary cracks. [ABSTRACT FROM AUTHOR]

The microbiomes associated with bee nests influence colony health through various mechanisms, although it is not yet clear how honeybee congeners differ in microbiome assembly processes, in particular the degrees to which floral visitations and the environment contribute to different aspects of diversity. We used DNA metabarcoding to sequence bacterial 16S rRNA from honey and stored pollen from nests of 4 honeybee species (Apis cerana, A. dorsata, A. florea, and A. laboriosa) sampled throughout Yunnan, China, a global biodiversity hotspot. We developed a computational pipeline integrating multiple databases for quantifying key facets of diversity, including compositional, taxonomic, phylogenetic, and functional ones. Further, we assessed candidate drivers of observed microbiome dissimilarity, particularly differences in floral visitations, habitat disturbance, and other key environmental variables. Analyses revealed that microbiome alpha diversity was broadly equivalent across the study sites and between bee species, apart from functional diversity which was very low in nests of the reclusive A. laboriosa. Turnover in microbiome composition across Yunnan was driven predominantly by pollen composition. Human disturbance negatively impacted both compositional and phylogenetic alpha diversity of nest microbiomes, but did not correlate with microbial turnover. We herein make progress in understanding microbiome diversity associated with key pollinators in a biodiversity hotspot, and provide a model for the use of a comprehensive informatics framework in assessing pattern and drivers of diversity, which enables the inclusion of explanatory variables both subtly and fundamentally different and enables elucidation of emergent or unexpected drivers. [ABSTRACT FROM AUTHOR]

Reinforcing steel bar can exert its strength and ductility by bonding to concrete. However, corrosion of steel bars reduces the bonding effect. This study mainly investigated the coupling effects of fly ash (FA) and corrosion on bond behavior. The impressed current method was utilized to achieve the target corrosion degrees. Three crucial factors that have impact on bond behavior was considered, which were FA content, corrosion degree and stirrups. The bond behavior was discussed using the bond‐slip curves. The results showed that the slight corrosion (less than 2.1%) can improve the bond behavior, the supplement of 15% FA can result in a higher ultimate bond strength and to a substantial extent offset the reduction in bond strength owing to the severe corrosion of rebar. The effects of stirrups on bond strength mainly focused on fly ash concrete (FAC) and had an almost negligible impact on ordinary concrete. The results and discussions can be of great significance to establish the bond‐slip constitutive model under multi‐factor coupling conditions and also can give some important advices to the design of engineering structures. [ABSTRACT FROM AUTHOR]

How many species of life are there on Earth? This is a question that we want to know but cannot yet answer. Some scholars speculate that the number of species may reach 2.2 billion when considering cryptic diversity and that each morphology‐based insect species may contain an average of 3.1 cryptic species. With nearly two million described species, such high estimates of cryptic diversity would suggest that cryptic species are widespread. The development of molecular species delimitation has led to the discovery of a large number of cryptic species, and cryptic biodiversity has gradually entered our field of vision and attracted more attention. This paper introduces the concept of cryptic species, how they evolve, and methods by which they may be discovered and confirmed, and provides theoretical and methodological guidance for the study of hidden species. A workflow of how to confirm cryptic species is provided. In addition, the importance and reliability of multi‐evidence‐based integrated taxonomy are reaffirmed as a way to better standardize decision‐making processes. Special focus on cryptic diversity and increased funding for taxonomy is needed to ensure that cryptic species in hyperdiverse groups are discoverable and described. An increased focus on cryptic species in the future will naturally arise as more difficult groups are studied, and thereby, we may finally better understand the rules governing the evolution and maintenance of cryptic biodiversity. [ABSTRACT FROM AUTHOR]