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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]

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]

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]

Aim: The Massenerhebung effect (Mass elevation effect) refers to heat‐ or wind‐driven altitudinal distribution patterns of temperature‐dependent parameters among massifs with narrower range and lower elevation around peripheral and isolated mountains compared to core and continuous ones. Although common in ecology, this effect is rarely discussed in population genetics. Here, we use genetic markers to reveal population genetic patterns and also test the mountain‐ and sky‐barrier hypotheses relevant to the Massenerhebung distribution pattern of Acer morrisonense in Taiwan's rugged topography and varied local climates. Location: The alpine and cloud forest of Taiwan. Taxon: Acer morrisonense Hayata. Methods: Two chloroplast DNA (cpDNA) fragments and 17 expressed sequence tag‐simple sequence repeat (EST‐SSR) loci, respectively, from 200 to 286 individuals were used to elucidate the phylogeographic pattern of pollen and seed dispersal of A. morrisonense. These data were combined with ecological niche modeling (ENM) to infer distribution range shifts and refugia. We also correlated the genetic‐divergence indices with spatial factors to clarify latitudinal and altitudinal effects on genetic diversity. Results: The incongruent phylogeographic patterns of genetic distributions between nuclear and cpDNA markers indicate unhindered pollen flow but spatially constrained seed dispersal. Taken together with ENM, the genetic pattern further reflects historical colonization from central‐mountain refugia to edges since the Holocene. The Massenerhebung reduces the gene flow by the surrounding mountains and also causes lower genetic diversity compared to central alpine populations. Main conclusions: This study is the first to reveal the influence of Massenerhebung effect on cpDNA genetic structure of montane trees and reflect the spatial trends of seed dispersal. This population genetic pattern can also be attributed to the demography‐related range shifts with paleoclimate fluctuations under complex mountain topography, supporting the mountain‐barrier hypothesis. The results have important implications for conserving the genetic diversity of species with a wide altitudinal distribution range. [ABSTRACT FROM AUTHOR]

TaHf thin films were deposited by performing the cosputtering of Ta and Hf targets. The results indicated that TaHf alloy is suitable for use as a resistive layer for thin film chip resistors and a replacement for NiCr and TaN x alloys. Maintaining the Hf:Ta ratio at approximately 1:1 produced the highest resistivity of 5.7 × 10−4 Ωcm when compared with TaN x and NiCr alloy thin films. This ratio also yielded a smaller temperature coefficient of resistance of −330 ppm/°C compared with TaN x thin films. Furthermore, the temperature coefficient of resistance of most TaHf thin films could be adjusted closer to zero through annealing. The increased Hf content in TaHf alloy was attributed to its poorer thermal stability and anticorrosion property relative to pure Ta films. However, the anticorrosion property of TaHf thin films was still stronger than that of NiCr thin films. • TaHf is a promising alternative material to TaN and NiCr for thin film resistor applications. • TaHf thin film possesses a smaller TCR and higher resistivity compared to TaN. • Anticorrosion properties of TaHf are stronger than those of NiCr. • TaHf thin film achieves a near-zero TCR by annealing if its oxygen content is low. [ABSTRACT FROM AUTHOR]

Ta–N–Al thin films were produced by reactive sputtering with two different TaAl alloys (Al 10 at.% and 20 at.%) for use as resistive materials for thin film chip resistors. Changing the N 2 gas flow of the N 2 /Ar plasma and the Al ratio in TaAl alloy resulted in different microstructures and electrical properties of the Ta–N–Al thin film. The resistivity of the thin film sputtered by TaAl (Al 20 at.%) alloy was 1.23 times that sputtered by Ta under 20% N 2 /Ar. After deposition, rapid thermal processing was applied to anneal the thin films for 5 min at 600 °C, 650 °C, and 700 °C under N 2 (99.995%) atmosphere, causing the Ta 2 N and TaN crystalline phase formation. Al in Ta–N–Al was observed to hinder Ta 2 N and TaN crystalline phase formation during annealing. It is crucial to dope Al ith Ta–N appropriately to obtain a near-zero temperature coefficient of resistance (TCR) after annealing. The TCR of Ta–N–Al thin film, sputtered by TaAl (Al 20 at.%) alloy, was substantially affected by the annealing temperature. However, the thin film sputtered by TaAl (Al 10 at.%) alloy under 16% N 2 /Ar can achieve a TCR of −1.8 ppm/°C and 1.4 ppm/°C after annealing at 600 °C and 650 °C, respectively. • Ta-N-Al with adequate Al has a higher resistivity than Ta-N. • Get near-zero TCR of Ta-N-Al by annealing within a specific temperature range. • Al in Ta-N-Al hinders Ta 2 N and TaN grain growth during annealing. [ABSTRACT FROM AUTHOR]