The observed ratio of Wolf–Rayet (WR) star subtypes (e.g., WC/WN) in M31 is significantly higher than the predictions of standard stellar evolution models, yet this key diagnostic discrepancy remains unresolved. This is partly due to incomplete census and the challenge of resolving individual stars in compact clusters with ground-based telescopes. In this work, we report a young cluster with WR features with the (R.A., Dec) = (00:43:39.36, +41:10:08.7), discovered with LAMOST spectra. We use the high spatial resolution of the HST imaging data to resolve the cluster members, leading to the identification of four WR star candidates, four OB stars, and one yellow supergiant. Based on the current known WR sample in M31 observed in the HST F275W filter, about one-third of WRs are contaminated by other sources within a 1.″1×1.″1 aperture, while this fraction can reach up to two-thirds for the LAMOST fiber size of 3.″3. Applying the approach demonstrated in this work to a larger sample of crowded regions in M31 will yield a more complete census and allow for the measurement of a definitive WC/WN ratio, corrected for contamination. Whether this refined ratio increases or decreases the current tension with models remains to be seen, but it will provide the essential observational constraint needed to advance our understanding.

Abstract Traditional species distribution models often have limitations in capturing invasion intensity, which reduces their effectiveness for invasive species management. To address this gap, we developed an integrated framework combining habitat suitability, population abundance, and ecosystem service value (ESV) risk assessment for Xanthium spinosum in China. Results revealed significant spatial heterogeneity, with high suitability areas concentrated along the Shanxi–Shaanxi–Gansu–Ningxia–Inner Mongolia border and high abundance areas mainly in the Ili Valley and central Inner Mongolia. Key environmental drivers of invasion included annual precipitation, warmest quarter precipitation, human footprint, and topsoil pH. ESV risk assessment projected substantial ecological and economic losses, with the greatest impacts on food production and climate regulation. High-risk areas for ESV overlap with high suitability and abundance regions, highlighting the urgent need for targeted management strategies. This study provides a robust, evidence-based framework to guide invasive species management in ecologically fragile and economically critical regions.

Invasive species exhibit heterogeneous invasion risks, a comprehensive paradigm for assessing and managing risks across scales, stages, and dimensions is required. Thus, we proposed an improved invasion risk management paradigm framework. Using the framework as a methodological system, we revealed that the invasion success of alien cockleburs is influenced by their intrinsic advantages, resource availability, differentiation in economic utility, and the frequency of accidental interception. We identified adaptive mechanisms and key drivers from different perspectives such as environmental niches and genetics and at different nodes such as introduction, colonization, abundance-related, and dispersal. The effects of key drivers on local abundance were primarily mediated by habitat suitability. Cockleburs showed distinct preferences for specific micro-functional landscapes: croplands, urban areas, and temperate forests require prioritized prevention. Spatially targeted strategies must incorporate latitude gradients and dispersal pathway characteristics. These findings support adopting an 'ecological precision surgery' model in biological invasion management.

Climate warming is affecting the ranges and population dynamics of invasive species, including insects, which have become a global problem, causing biodiversity declines and agricultural economic losses. Anthonomus eugenii as an important invasive pest on pepper is now mainly located in the USA and Mexico. However, the global potential geographic distribution (PGD) of A. eugenii with climate change remains unknown, which makes it difficult to monitor and control. In this study, based on the global distribution areas and important environmental variables, we constructed an ensemble model to predict the global PGD of A. eugenii under the current climate and three climate scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5) in the 2030s and 2050s. The mean true skill statistics (TSS) and the area under the receiver operating characteristic curve (AUC) of the EM were 0.825 and 0.988, respectively, indicating that the EM was reliable. The mean temperature of the driest (bio9) and wettest (bio8) quarter and precipitation of the coldest quarter (bio19) were the most important environmental variables affecting the PGD of A. eugenii. Under the current climate, the PGD of A. eugenii was mainly concentrated in southern North America and central South America. The suitable areas of A. eugenii could increase significantly, reaching the maximum under SSP5-8.5 in the 2030s, approximately 1911.7 × 104 km2. Moreover, the distribution centroid would shift to higher latitudes with global warming. It also had the potential invasion risk in Russia, China, the Republic of the Congo, and Romania, which should enhance quarantine control and early warning.

Invasive sandburs (Cenchrus spp.), tropical and subtropical plants, are preferred in grasslands and agricultural ecosystems worldwide, causing significant crop production losses and reducing native biodiversity. Integrating phylogenetic relatedness and potentially suitable habitats (PSHs) to identify areas at risk of invasion is critical for prioritizing management efforts and supporting decisions on early warning and surveillance for sandbur invasions. However, despite risk assessments for individual Cenchrus species, the combined analysis of suitable habitats and phylogenetic relationships remains unclear. Therefore, this study aims to assess the invasion risk regions-including PSHs, species richness (SR), and phylogenetic structure-of eight invasive and potentially invasive sandburs in China, to quantify their niche overlap and identify driving factors. Our results showed that the phylogenetic distance of potentially invasive sandburs was closely related to invasive sandburs. Especially, three potentially invasive sandburs, C. ciliaris, C. setigerus, and C. myosuroides, possessed invasion potential resulting from close phylogenetic relatedness and high climatic suitability compared with invasive sandburs. The PSHs for invasive sandburs were distributed in wider regions except northwest China and had higher suitability to different environmental conditions. Potentially invasive sandburs were primarily located in southwestern and southern China driven by precipitation, especially, being inspected in Guangdong, Hainan, and Yunnan on numerous occasions, or potentially introduced in Guangxi, Taiwan, and Fujian for sandburs invasion hotspots. The phylogenetic clustering for eight sandburs occurred in the eastern, center, and southern coastal China, where higher SR in distribution was correlated with invasion hotspots. The SR and phylogenetic relatedness metrics were related to temperature and topographic variables. Totally, the expansion and invasion risk could be increased toward higher latitudes under future global warming. These findings offer novel insights for the prevention and management of sandburs invasions.

Giant planets like Jupiter and Saturn, play important roles in the formation and habitability of Earth-like planets. The detection of solar system analogs that have multiple cold giant planets is essential for our understanding of planet habitability and planet formation. Although transit surveys such as Kepler and TESS have discovered thousands of exoplanets, these missions are not sensitive to long period planets due to their limited observation baseline. The Tianyu project, comprising two 1-meter telescopes (Tianyu-I and II), is designed to detect transiting cold giant planets in order to find solar system analogs. Featuring a large field of view and equipped with a high-speed CMOS camera, Tianyu-I will perform a high-precision photometric survey of about 100 million stars, measuring light curves at hour-long cadence. The candidates found by Tianyu-I will be confirmed by Tianyu-II and other surveys and follow-up facilities through multi-band photometry, spectroscopy, and high resolution imaging. Tianyu telescopes will be situated at an elevation about 4000 meters in Lenghu, China. With a photometric precision of 1% for stars with V < 18 mag, Tianyu is expected to find more than 300 transiting exoplanets, including about 12 cold giant planets, over five years. A five-year survey of Tianyu would discover 1-2 solar system analogs. Moreover, Tianyu is also designed for non-exoplanetary exploration, incorporating multiple survey modes covering timescales from sub-seconds to months, with a particular emphasis on events occurring within the sub-second to hour range. It excels in observing areas such as infant supernovae, rare variable stars and binaries, tidal disruption events, Be stars, cometary activities, and interstellar objects. These discoveries not only enhance our comprehension of the universe but also offer compelling opportunities for public engagement in scientific exploration.

Invasive alien insects directly or indirectly driven by climate change threaten crop production and increase economic costs worldwide. Ectomyelois ceratoniae (Zeller) is a highly reproductive invasive crop insect that can severely damage fruit commodities and cause significant economic losses globally. Estimating the global potentially suitable habitats (PSH) of E. ceratoniae is an important aspect of its invasive risk assessment and early warning. Here, we constructed an optimized MaxEnt model based on the global distribution records of E. ceratoniae, and nine environmental variables (EVs), to predict its global PSH under current and future climates. Our results showed that the RM value was 2.0 and the mean area under receiver operating characteristic curve (AUC) value was 0.972, indicating the high accuracy of the optimal MaxEnt model. The mean temperature of driest quarter (bio9, 50.2%), mean temperature of wettest quarter (bio8, 16.9%), temperature seasonality (bio4, 9.7%), and precipitation of coldest quarter (bio19, 9.1%) were the significant EVs affecting its distribution patterns. The global PSH of E. ceratoniae are mainly located in western Asia under current climate scenarios (687.57 × 104 km2), which showed an increasing trend under future climate scenarios. The PSH of E. ceratoniae achieved the maximum under the shared socioeconomic pathway (SSP) 1–2.6 in the 2030s and under the SSP2-4.5 in the 2050s. The increased PSH of E. ceratoniae are mainly located in southwestern Asia, northwestern Europe, northwestern South America, northwestern North America, southern Oceania, and northwestern Africa. Our findings suggest that quarantine officials and governmental departments in the above high-risk invasion areas should strengthen monitoring and early warning to control E. ceratoniae; in particular, cultural measures should be taken in areas where its further expansion is expected in the future.

Epiphyas postvittana, commonly known as the light brown apple moth (LBAM), is native to Australia and has a restricted global distribution. Its polyphagous nature and the recent surge in interceptions have emphasized the need for focused risk assessments to guide effective measures to curb the entry of this pest into new countries. This study aimed to perform a detailed global invasion risk assessment using an optimized MaxEnt model that incorporated 19 bioclimatic variables and elevation. The predictive outcomes underscored the significance of key variables, specifically the minimum temperature of the coldest month (bio6), precipitation of the driest month (bio14), and precipitation of the coldest quarter (bio19), in shaping the potential geographical distribution of LBAM. Regions beyond the existing range, including the southeastern United States, southern Brazil, eastern Argentina, Uruguay, southern Chile, and various Western European countries, were identified as susceptible to invasion and establishment by LBAM. An increase in suitability was observed above 45°N and 40°S under future climate scenario. With respect to climate change, LBAM would expand its potential range in Western Europe and the United States, especially under SSP5-8.5, in the 2050s. An upward trend in the latitudinal suitability gradient for LBAM in mid-high latitude areas implies that amid changing climate conditions, LBAM may find favorable habitats in these regions. For countries and regions with invasion risk, it is imperative to implement corresponding inspections and quarantine measures to thwart the introduction of LBAM, particularly in countries with established trade ties with invaded regions.

Solanum viarum has become extensively invasive owing to international trade, climate change, and land-use change. As it is classified as a quarantine weed by countries such as the U.S. and Mexico, it is critical to understand the prevailing historical dispersal, ecological niche dynamics, and distribution patterns. We reconstructed the historical invasion countries and analyzed the ecological niche shift of S. viarum. Using MaxEnt based on the conservativeness of ecological niches, we studied variations in the potential geographical distributions (PGDs) of S. viarum in ecosystems and variations in suitability probabilities along latitudinal gradients. The invasion history in six continents involved three phases: lag (before 1980), spread (1980-2010), and equilibrium (2010-present). The ecological niche remains conserved. The area of S. viarum PGDs had increased by 259 km2; the PGDs will expand to reach a maximum in the 2050s, SSP5-8.5. The PGDs of S. viarum will migrate to higher latitudes under the same future climate scenarios. The latitudes subject to high threats range from 20° to 30° in forest and cropland ecosystems, 15.5° to 27.5° (northern hemisphere) and 33.1° to 42.8° (southern hemisphere) in grassland ecosystems, and 20° to 35° in urban ecosystems. Global change has led to an increased threat of S. viarum at high latitudes. These findings provide a theoretical basis to monitor and control S. viarum.

Introduction The establishment of invasive alien plants (IAPs) is primarily driven by climate warming and human activities, and their populations have a negative impact on agricultural economics, ecological systems, and human health. Lolium temulentum and Aegilops tauschii are critical IAPs in China because they reduce the quality of cereal grains and decrease wheat yields. Lolium temulentum is a winter-temperate weed that spreads easily and is poisonous to humans and animals. Aegilops tauschii is resistant to herbicides, has a high reproductive rate, and frequently grows in wheat. Both species have been listed in the Ministry of Agriculture and Rural Affairs of the People’s Republic of China’s management catalog since 2006. Methods In the present study, the historical occurrence and invasion of each species were collected and reconstructed, which showed that the population outbreak of L. temulentum began in 2010, whereas that of A. tauschii began in 2000. Using the optimal MaxEnt model, the geographical distributions of L. temulentum and A. tauschii were predicted based on screened species occurrences and environmental variables under the current and three future scenarios in the 2030s and 2050s (i.e., SSP1-2.6, SSP2-4.5, and SSP5-8.5). Results The mean AUC values were 0.867 and 0.931 for L. temulentum and A. tauschii , respectively. Human influence index (HII), mean temperature of coldest quarter (bio11), and precipitation of coldest quarter (bio19) were the most significant variables for L. temulentum , whereas human influence index, temperature seasonality (standard deviation×100) (bio4), and annual mean temperature (bio1) were the critical environmental variables for A. tauschi. Suitable habitat areas in China for L. temulentum and A. tauschii currently covered total areas of 125 × 10 4 and 235 × 10 4 km 2 , respectively. Future suitable areas of L. temulentum reached the maximum under SSP2-4.5, from 2021 to 2060, whereas for A. tauschii they reached the maximum under SSP5-8.5, from 2021 to 2060. Furthermore, the overlap area under the current climate conditions for L. temulentum and A. tauschii was approximately 90 × 10 4 km 2 , mainly located in Hubei, Anhui, Jiangsu, Shandong, Henan, Shaanxi, Shanxi, and Hebei. The overlap areas decreased in the 2030s, increased in the 2050s, and reached a maximum under SSP1-2.6 (or SSP2-4.5) with an approximate area of 104 × 10 4 km 2 . The centroid of L. temulentum in Henan was transferred to the southwest, whereas for A. tauschii it transferred to higher latitudes in the northeast. Discussion Our findings provide a practical reference for the early warning, control, and management of these two destructive IAP populations in China.

Invasive crop pests (ICPs) are a major cause of crop losses and adversely affect global food security. Diuraphis noxia Kurdjumov is a significant ICP that feeds on the sap of crops, reducing crop yield and quality. Although estimating the geographical distribution patterns of D. noxia under climate change is critical for its management and global food security, such information remains unclear. Based on 533 global occurrence records and 9 bioclimatic variables, an optimized MaxEnt model was used to predict the potential global geographical distribution of D. noxia. The results showed that Bio1, Bio2, Bio7, and Bio12 were significant bioclimatic variables that influenced the potential geographical distribution of D. noxia. Under current climatic conditions, D. noxia was mainly distributed in west-central Asia, most of Europe, central North America, southern South America, southern and northern Africa, and southern Oceania. Under the SSP 1-2.6, SSP 2-4.5, and SSP 5-8.5 scenarios for the 2030s and 2050s, the potential suitable areas increased, and the centroid migrated to higher latitudes. The early warning of D. noxia in northwestern Asia, western Europe, and North America should be attended to further. Our results provide a theoretical basis for early monitoring and warning of D. noxia worldwide.

We present an atmospheric analysis of LTT 9779 b, a rare planet situated in the hot Neptune desert, that has been observed with HST WFC3 G102 and G141. The combined transmission spectrum, which covers 0.8 - 1.6 $\mu$m, shows a gradual increase in transit depth with wavelength. Our preferred atmospheric model shows evidence for H$_{\rm 2}$O, CO$_{\rm 2}$ and FeH with a significance of 3.1 $\sigma$, 2.4 $\sigma$ and 2.1 $\sigma$, respectively. In an attempt to constrain the rate of atmospheric escape for this planet, we search for the 1.083 $\mu$m Helium line in the G102 data but find no evidence of excess absorption that would indicate an escaping atmosphere using this tracer. We refine the orbital ephemerides of LTT 9779 b using our HST data and observations from TESS, searching for evidence of orbital decay or apsidal precession, which is not found. The phase-curve observation of LTT 9779 b with JWST NIRISS should provide deeper insights into the atmosphere of this planet and the expected atmospheric escape might be detected with further observations concentrated on other tracers such as Lyman $\alpha$.

Sorghum halepense competes with crops and grass species in cropland, grassland, and urban environments, increasing invasion risk. However, the invasive historical dynamics and distribution patterns of S. halepense associated with current and future climate change and land-use change (LUC) remain unknown. We first analyzed the invasive historical dynamics of S. halepense to explore its invasion status and expansion trends. We then used a species distribution model to examine how future climate change and LUC will facilitate the invasion of S. halepense. We reconstructed the countries that have historically been invaded by S. halepense based on databases with detailed records of countries and occurrences. We ran biomod2 based on climate data and land-use data at 5′ resolution, assessing the significance of environmental variables and LUC. Sorghum halepense was widely distributed worldwide through grain trade and forage introduction, except in Africa. Europe and North America provided most potential global suitable habitats (PGSHs) for S. halepense in cropland, grassland, and urban environments, representing 48.69%, 20.79%, and 84.82%, respectively. The future PGSHs of S. halepense increased continuously in the Northern Hemisphere, transferring to higher latitudes. Environmental variables were more significant than LUC in predicting the PGSHs of S. halepense. Future PGSHs of S. halepense are expected to increase, exacerbating the invasion risk through agricultural LUC. These results provide a basis for the early warning and prevention of S. halepense worldwide.

Invasive alien plants posed a significant threat to natural ecosystems, biodiversity, agricultural production, as well as human and livestock health. Lolium temulentum, an annual invasive alien weed with fibrous roots, can reduce wheat production and cause economic losses. Moreover, the consumption of grains or cereal products mixed with darnel can cause dizziness, vomiting, and even death. Therefore, darnel is regarded as one of ″the worst weeds around the world″. In the present study, we predicted the potential global geographical distribution of L. temulentum using an optimal MaxEnt model, based on occurrence records and related environmental variables. The mean AUC, TSS, and KAPPA were 0.95, 0.778, and 0.75, indicating the MaxEnt model accuracy was excellent. The significant environmental variables, including the mean temperature of coldest quarter (bio 11), precipitation of coldest quarter (bio 19), temperature annual range (bio 7), and annual precipitation (bio 12), produced a great impact on the potential global geographical distribution of L. temulentum. Under the current climate, L. temulentum was primarily distributed in south-eastern Asia, Europe, and south-eastern North America. The widest total suitable habitat was distributed in Asia, covering nearly 796 × 104 km2. By the 2050s, the potential geographical distribution of L. temulentum was expected to decrease in the Northern Hemisphere, and shrink gradually in southern America, Africa, and Oceania. Moreover, the distribution center of L. temulentum was expected to shift from Asia to Europe. Based on these predictions, changes in the suitable habitats for L. temulentum between Europe and Asia warrant close attention to prevent further spread.

Mass loss is a key property to understand stellar evolution and in particular for low-metallicity environments. Our knowledge has improved dramatically over the last decades both for single and binary evolutionary models. However, episodic mass loss although definitely present observationally, is not included in the models, while its role is currently undetermined. A major hindrance is the lack of large enough samples of classified stars. We attempted to address this by applying an ensemble machine-learning approach using color indices (from IR/Spitzer and optical/Pan-STARRS photometry) as features and combining the probabilities from three different algorithms. We trained on M31 and M33 sources with known spectral classification, which we grouped into Blue/Yellow/Red/B[e] Supergiants, Luminous Blue Variables, classical Wolf-Rayet and background galaxies/AGNs. We then applied the classifier to about one million Spitzer point sources from 25 nearby galaxies, spanning a range of metallicites (1/15 to ∼3 Z_⊙). Equipped with spectral classifications we investigated the occurrence of these populations with metallicity.

针对计量自动化系统普遍存在的档案一致性差、实时监控效果不佳以及数据价值尚未深入发掘等问题,结合电网电能量数据上传要求,主要针对计量运行数据深化应用与故障智能识别开展应用研究。以云平台作为基础平台支撑,构建了计量数据智能分析平台,能够对计量档案完成质量分析,并对异常数据进行提取和处理,有效解决档案一致性问题。该平台可依据典型计量故障数据,智能化构建计量故障池,对海量计量数据进行分析,并识别出疑似的计量故障数据,辅助运维人员开展计量设备的运维工作。该平台还可基于计量海量数据的分析与挖掘,实现客户日用电情况、异常数据监控等数据高级分析应用。文中研究对于我国泛在电力物联网在计量自动化领域的实践提供了可靠借鉴。

近年来,在电真空技术进一步发展和概念创新的基础上,借助于材料、工艺及微加工技术的进步,大功率毫米波器件取得了快速发展,诞生了大功率毫米波回旋行波管、W波段宽带行波管、准太赫兹行波管、毫米波扩展互作用速调管、集成微型行波管等新管型.在毫米波频段取得了输出功率100 W～100 kW、带宽6～10 GHz等标志性成果.利用上述性能优良的电真空器件结合雷达探测新技术,开展毫米波单脉冲精密测量及目标成像雷达、毫米波空间合成无源相控阵多目标监视雷达、毫米波微型行波管有源相控阵多功能一体化雷达、机载亚毫米波视频合成孔径雷达研究,突破大功率毫米波器件应用和发射机关键技术,实现大功率毫米波雷达空间目标的多维特征精细测量和成像等应用目标.