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Aim: Rapid global warming is threatening global biodiversity, and it will likely lead to varying degrees of local adaptation, particularly amongst plant species. Besides, rising temperatures frequently result in upslope distribution shifts towards climatic optima (i.e. the escalator effect) within a limited dispersal space, such as in insular environments. Here, we integrated ecological and genetic approaches to investigate how climate change will impact the genetic compositions and spatial distributions of Taiwan's endemic maple Acer caudatifolium. Location: Taiwan. Methods: We estimate the distribution range shifts of A. caudatifolium under climate change through species distribution modelling (SDM). We also use 368 genotyped samples to infer dispersal and genetic hotspots and quantify the contributions of geography/environments to genetic variations. We further assess the potential risk to A. caudatifolium under different climate warming scenarios. Results: We detected three genetic diversity hotspots near mountainous glacial refugia and two dispersal hotspots in northern Taiwan and the central‐to‐southern Central Mountain Range. Overall range reductions and an altitudinal upslope shift were observed in SDM. Using both linear and nonlinear regression approaches, we found that genetic variation was significantly associated with geographic distance and elevation‐related climatic variables. The potential risk analysis revealed that the northernmost summit‐dwelling populations were the most vulnerable. Furthermore, the major risk factor differed amongst populations: for central populations, temperature and precipitation jointly determined the potential risk, whereas precipitation was the only risk factor for northern and southern populations. Main conclusions: This case study demonstrates how various climate factors, mountain height and the availability of corridors jointly determine the demographic fates and sustainability of island maples in the face of climate change. This study also provided estimates of the implications of global warming, which can be conducive to developing appropriate conservation strategies. [ABSTRACT FROM AUTHOR]

Pollen grains are carriers of allergens, causing severe symptoms to hay fever sufferers. Due to annual variability in pollen levels, there is a need to develop a precise forecasting model that can accurately predict levels of annual airborne pollen for use by patients and medical personnel. In a previous study, we developed and tested a new pollen prediction algorithm based on past meteorological conditions in a flat region. In this study, we analyzed pollen samples (spring 1997–2016) and meteorological data (summer 1991–2015) from nine Swiss cities, using the algorithm to test its applicability in a mountainous region. However, we found variations in model applicability (r2 and RMSE) among the nine observation sites. Based on considerations of topographical influence on the spatial representativeness of airborne pollen data, we then investigated the relationships between these indices and topographical features at varying spatial ranges. The results suggested that the applicability of the algorithm to annual total airborne pollen forecasts can indicate the spatial representativeness of observed airborne pollen concentrations: r2 and RMSE reflected deviations in airborne pollen concentration caused by dispersal conditions at local and meso-scales, respectively. At higher-altitude monitoring sites, the local spatial representativeness of airborne pollen declined due to the influence of local topography-driven climate. On the other hand, dispersal conditions in the atmospheric boundary layer may deteriorate the meso-scale representativeness of airborne pollen at monitoring sites with higher terrain complexity. This study provides a reference approach to determining the spatial representativeness of airborne pollen data by applying the pollen forecast algorithm. Image 1 • Accurate methods for predicting annual pollen are essential for public health. • This study tested a new algorithm for annual airborne pollen in a mountainous area. • A clear relationship between model applicability and topography was found. • The results' accuracy was affected by local and meso-scale dispersal. • The method's applicability indicated the spatial representativeness of pollen data. [ABSTRACT FROM AUTHOR]

Understanding species boundaries maintenance in the face of hybridization/introgression is an intriguing yet complex topic in evolutionary biology. The underlying mechanisms, however, remain elusive. To address this, we propose to investigate the role of climatic shifts in shaping genetic structure and influencing species boundaries. We combine multilocus genetic data and species distribution modeling to explore how past and current climatic shifts affect the genetic structure and demographic history of two Taiwan endemic gingers, Zingiber pleiostachyum and Z. shuanglongense. We identified a well-delimited genetic structure with evidence of admixture, indicating incomplete reproductive isolation between the two gingers. This is likely due to secondary contact and range overlap during the last glacial maximum, leading to sporadic instances of hybridization. Niche overlap tests based on climate and soil data indicate that these two gingers occupy similar but nonidentical ecological niches. Furthermore, we found that the considerable differences in their current geographic distribution and altitude preferences might have resulted from different seed dispersal capabilities and competitive exclusion due to their similar niche preferences. Our results reveal a model where altitudinal differentiation and dispersal strategy synergistically reinforce the species divergence, thereby illuminating the importance of these factors in shaping and maintaining the island's biodiversity. [ABSTRACT FROM AUTHOR]

The rapid spread of influenza-associated H1N1 viruses has caused serious concern in recent years. Therefore, there is an urgent need for the development of automatic, point-of-care devices for rapid diagnosis of the influenza virus. Conventional approaches suffer from several critical issues; notably, they are time-consuming, labor-intensive, and are characterized by relatively low sensitivity. In this work, we present a new approach for fluorescence-based detection of the influenza A H1N1 virus using a sandwich-based aptamer assay that is automatically performed on an integrated microfluidic system. The entire detection process was shortened to 30 min using this chip-based system which is much faster than the conventional viral culture method. The limit of detection was significantly improved to 0.032 hemagglutination unit due to the high affinity and high specificity of the H1N1-specific aptamers. The results showed that the two-aptamer microfluidic system had about 10 3 times higher sensitivity than the conventional serological diagnosis. It was demonstrated that the developed microfluidic system may play as a powerful tool in the detection of the H1N1 virus. [ABSTRACT FROM AUTHOR]

A new root canal sealer was developed based on urethane acrylates using polycarbonate polyol (PCPO), a macrodiol prepared in the consumption of carbon dioxide as feedstock. The superior mechanical properties and biostability nature of PCPO-based urethane acrylates were then co-crosslinked with a difunctional monomer of tripropylene glycol diarylate (TPGDA) as sealers for resin matrix. Moreover, nanoscale silicate platelets (NSPs) immobilized with silver nanoparticles (AgNPs) and/or zinc oxide nanoparticles (ZnONPs) were introduced to enhance the antibacterial effect for the sealers. The biocompatibility and the antibacterial effect were investigated by Alamar blue assay and LDH assay. In addition, the antibacterial efficiency was performed by using Enterococcus faecalis (E. faecalis) as microbial response evaluation. These results demonstrate that the PCPO-based urethane acrylates with 50 ppm of both AgNP and ZnONP immobilized on silicate platelets, i.e., Ag/ZnO@NSP, exhibited great potential as an antibacterial composite for the sealer of root canal obturation. [ABSTRACT FROM AUTHOR]

In addition to the Warburg effect, which increases the availability of energy and biosynthetic building blocks in WSSV-infected shrimp, WSSV also induces both lipolysis at the viral genome replication stage (12 hpi) to provide material and energy for the virus replication, and lipogenesis at the viral late stage (24 hpi) to complete virus morphogenesis by supplying particular species of long-chain fatty acids (LCFAs). Here, we further show that WSSV causes a reduction in lipid droplets (LDs) in hemocytes at the viral genome replication stage, and an increase in LDs in the nuclei of WSSV-infected hemocytes at the viral late stage. In the hepatopancreas, lipolysis is triggered by WSSV infection, and this leads to fatty acids being released into the hemolymph. β-oxidation inhibition experiment reveals that the fatty acids generated by WSSV-induced lipolysis can be diverted into β-oxidation for energy production. At the viral late stage, WSSV infection leads to lipogenesis in both the stomach and hepatopancreas, suggesting that fatty acids are in high demand at this stage for virion morphogenesis. Our results demonstrate that WSSV modulates lipid metabolism specifically at different stages to facilitate its replication. Investigation into the lipid metabolism shifts occurring in shrimp infected with white spot syndrome virus provides insight into how this virus modulates host metabolism in a way that creates a favorable environment for its replication. [ABSTRACT FROM AUTHOR]

During an early epoch of development, the brain is highly adaptive to the stimulus environment. Exposing young animals to a particular tone, for example, leads to an enlarged representation of that tone in primary auditory cortex. While the neural effects of simple tonal environments are well characterized, the principles that guide plasticity in more complex acoustic environments remain unclear. In addition, very little is known about the perceptual consequences of early experience-induced plasticity. To address these questions, we reared juvenile rats in complex multitone environments that differed in terms of the higher-order conditional probabilities between sounds. We found that the development of primary cortical acoustic representations, as well as frequency discrimination ability in adult animals, were shaped by the higher-order stimulus statistics of the early acoustic environment. Our results suggest that early experience-dependent cortical reorganization may mediate perceptual changes through statistical learning of the sensory input. [ABSTRACT FROM AUTHOR]

In this study, vanadium (V) was used as a top electrode in a vanadium oxide (VOx)-based selector device. Electroforming was performed to form a threshold region with metal–insulator transition (MIT) at both V electrode and VOx switching layers without annealing during fabrication. The simple V/VOx/TiN structure obtained was scalable and compatible with complementary metal–oxide–semiconductors. All electrical measurement results indicated that V/VOx/TiN selectors exhibited excellent characteristics such as high uniformity, a short switching time of 60 ns, a robust endurance of >109 cycles, and high reliability and stability. Both the simulation analysis and current fitting method were applied to further validate experimental results. Consequently, we developed a nanoscale V/VOx/TiN selector with excellent characteristics, which can be potentially applied to future highdensity crossbar memory devices to overcome sneak-path problems. [ABSTRACT FROM AUTHOR]

In this paper, vanadium oxide (VOx) was chosen for the resistive switching layer in a typical resistive random access memory (RRAM) structure. During negative forming bias, we found an initial selector property. This indicates the presence of metal–insulator-transition characteristics in the VOx layer even without an annealing process. In order to study this phenomenon, material analyses were conducted, with results indicating that there are V-O stretching bonds and an oxide/vanadium ratio of nearly 2.2 (${O}/{V} = {2.2}$). In addition, the experimental results of the dc sweeping test indicated that off-state current gradually decreased after each cycle, meaning that the selectivity characteristics in the VOx selector could be improved. Endurance performance of our experimental devices reached 108, sufficient for integration with RRAM devices in a 1S1R array. To further investigate this special phenomenon, current fitting analysis and simulation analyses were conducted. The results of the fitting analysis indicated that the conduction mechanism for off-state current was Schottky emission and the Schottky distance increased with increasing numbers of cycles. In other words, oxide ions migrate toward the filament at low negative voltage during dc sweeping, causing the formation of VOx. Furthermore, the results of thermal field simulation analysis indicated that there is a thermal concentration effect in and around the filament. Thus, oxide ions more easily migrate toward the vanadium filament when a stronger electrical field is present around the filament during dc sweeping cycles. Finally, stable vanadium selector characteristics are obtained and a conduction filament behavior model is proposed. [ABSTRACT FROM AUTHOR]

This paper investigates the characteristics of applying indium–tin oxide (ITO) with and without nitride gas (N2) as the insulator in resistive random access memory (RRAM). After cosputtering an ITO target with N2 as the insulator and capping the same ITO material as the top electrode, the device exhibits rectifier and resistance switching characteristics before and after the forming process, respectively. The Schottky diodelike rectifier mechanism was also verified by various temperature measurements. Furthermore, robust resistance switching at a positive forming voltage, smaller than that required during negative bias forming, can be achieved. Both positive and negative forming processes are examined with current fitting results, which show different dominant mechanisms when using positive or negative biases. All these mechanisms have also been verified by temperature effect experiments, which confirmed the dominant conduction mechanisms. This, in combination with the fact that the positive forming voltage itself is smaller than the negative forming voltage, and decreases with device scale down, provides two highly beneficial results. This good performance achieved by using ITO with N2 suggests significant progress of RRAM and remarkable potential applications. [ABSTRACT FROM PUBLISHER]