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Ficus species (Moraceae) play pivotal roles in tropical and subtropical ecosystems. Thriving across diverse habitats, from rainforests to deserts, they harbor a multitude of mutualistic and antagonistic interactions with insects, nematodes, and pathogens. Despite their ecological significance, knowledge about the genomic background of Ficus remains limited. In this study, we report a chromosome-level reference genome of F. hirta, with a total size of 297.27 Mb, containing 28,625 protein-coding genes and 44.67% repeat sequences. These findings illuminate the genetic basis of Ficus responses to environmental challenges, offering valuable genomic resources for understanding genome size, adaptive evolution, and co-evolution with natural enemies and mutualists within the genus. [ABSTRACT FROM AUTHOR]

Ground motion parameters are crucial characteristics in earthquake warning and earthquake engineering practice. However, the existing methods are time-consuming and labor-intensive. In this study, a multi-task approach (GMP-MT) based on a hard parameter sharing strategy and single station data is proposed to improve the overall estimation accuracy by jointly optimizing the estimation of peak ground acceleration (PGA) and peak ground velocity (PGV). In addition, this study reshapes the mean squared error by adjusting the weight of the loss according to the data distribution to solve the data imbalance. The developed network structure extracts not only the seismic features from various dimensions but also the spatial–temporal correlations from large-dimensional seismic data. The designed model is trained and tested based on the global three-component seismic waveform data recorded in the STanford EArthquake Dataset. Experimental results show that the correlation coefficients of PGA and PGV are above 90%, and the average errors are less than 0.19. The model has good stability, specifically insensitive to epicenter distance, hypocentral depth, and signal-to-noise ratio. Furthermore, the superiority of the model in terms of learning and fitting is demonstrated by comparison with several state-of-the-art models in the existing literature. [ABSTRACT FROM AUTHOR]

Regional seismic networks often observe artificially induced seismic events such as blasting and collapses. Misclassified seismic events in the earthquake catalog can therefore interfere with assessments of natural seismic activity. Traditional methods rely on the period, and phase features of seismic waves to determine the nature of seismic events. We designed three seismic event classifiers with reference to convolutional neural network structures such as VGGnet, ResNet, and Inception. The designed classifiers were tested and compared using three-channel seismic full-waveform time-series data and spectral data. Our classifiers are shown to only require 60 s of full-waveform seismic event data and first-arrival times for alignment; additional phase labeling or numerical filtering is unnecessary. Rapid classification of earthquakes, blasting, and mine collapses can be achieved within approximately 1 min of an event. As a test case, this study uses 6.4 k observations of actual local seismic events with magnitudes ranging from ML 0.6 to ML 4.5 obtained from 47 broadband seismic stations in the Henan Regional Network of the China Seismological Network Center; these observations include natural earthquakes, blasting, and collapse events. The results indicate that our classifiers can reach a lower classification magnitude limit of ML 0.6 and that their recall and accuracy exceed 90%, outperforming manually performed routine classifications and similar approaches. These findings provide an important reference for the rapid classification of small and medium earthquakes. [ABSTRACT FROM AUTHOR]

Key message: Identification of infection process and defense response during M. oryzae infecting Acuce. Magnaporthe oryzae is a destructive rice pathogen. Recent studies have focused on the initial infectious stage, with a few studies conducted to elucidate the characteristics of the late infectious stages. This study aims to decipher the characteristics at different stages (biotrophic, biotrophy-necrotrophy switch (BNS), and necrotrophic) between the interaction of two M. oryzae-rice combinations and investigate the resistance mechanisms of rice to M. oryzae using cytological and molecular methods. The biotrophic phase of M. oryzae-LTH compatible interaction was found to be longer than that of M. oryzae-Acuce incompatible interaction. We also found that jasmonic acid (JA) signaling plays an important role in defense by regulating antimicrobial compound accumulation in infected Acuce via a synergistic interaction of JA-salicylic acid (SA) and JA-ethylene (ET). In infected LTH, JA-ET/JA-SA showed antagonistic interaction. Ibuprofen (IBU) is a JA inhibitor. Despite the above findings, we found that exogenous JA-Ile and IBU significantly alleviated blast symptoms in infected LTH at 36 hpi (biotrophic) and 72 hpi (BNS), indicating these two-time points may be critical for managing blast disease in the compatible interaction. Conversely, IBU significantly increased blast symptoms on the infected Acuce at 36 hpi, confirming that the JA signal plays a central role in the defense response in infected Acuce. According to transcriptional analysis, the number of genes enriched in the plant hormone signal pathway was significantly higher than in other pathways. Our findings suggested that JA-mediated defense mechanism is essential in regulating Acuce resistance, particularly during the biotrophic and BNS phases. [ABSTRACT FROM AUTHOR]

Me/Pt/CeO2/Al2O3 (Me: Mn and Cu) catalysts and Pt/CeO2/Al2O3 catalyst were synthesized by a solution chemical reduction method to reveal the influence of a small amount of transition metals on the CO-SCR reaction. Various of analysis technologies were performed to study the structure and texture, physicochemical property, adsorption ability, redox property and surface state of the catalysts. The results revealed that the BET surface area, CO adsorption ability and redox property of Pt catalyst were enhanced after the addition of transition metals. Moreover, the addition of Cu generated the maximum reduced Pt species, Ce3+ and surface oxygen species. And the synergistic interactions among Cu2+/Cu+, Ce4+/Ce3+ and Pt4+/Pt2+ were conductive to form more oxygen vacancies, which played a key role to promote the CO-SCR performance and resulted in the best CO-SCR activity of Cu modified Pt/CeO2/Al2O3 catalyst at 80–240 °C. [ABSTRACT FROM AUTHOR]

Key message: MoSDT1, a rice blast fungus transcription factor, is as an inducer to activate defense response through mainly mediating phosphorylated proteins in rice. Pathogen effector proteins play a dual role in infecting the host or triggering a defense response. Our previous research found a Magnaporthe oryzae effector, MoSDT1, which could activate the rice defense response when it was overexpressed in rice. However, we still know little about the mechanisms on how MoSDT1 in vivo or in vitro influences the resistance ability of rice. Our results showed that decreased ROS and increased lignin contents appeared along with significant upregulation of defense-related genes, raffinose synthesis gene, and phenylalanine ammonialyase gene. Moreover, we revealed that the contents of lignin were increased, which was in accordance with the upregulation of its precursor phenylalanine gene despite the fact that the glutamate-/thiamine-responsive genes were inhibited in MoSDT1 transgenic rice, and these indicated that MoSDT1 triggered the defense system of rice in vivo. Interestingly, in vitro studies, we further found that MoSDT1 induced the defense system by ROS synthesis, callose deposition, PR gene expression and SA/JA synthesis/signal genes using the purified prokaryotic expression system in rice plants. In addition, this defense response was confirmed to be activated by the zinc finger domain of MoSDT1 via prokaryotic expression of MoSDT1 truncated mutants in rice plants. To elucidate the regulative effects of MoSDT1 on protein phosphorylation in rice, phosphoproteome analysis was performed in both MoSDT1-transgenic and wild type rice. We found that MoSDT1 specifically up-regulated the expression levels of a few phosphorylated proteins, which were involved in multiple functions, such as biotic/abiotic stress and growth. In addition, the motifs in these specific proteins ranked the top among the top-five conserved motifs in the MoSDT1-transgenic rice. MoSDT1 played a crucial role in enhancing rice resistance by modulating several genes and signaling pathways. [ABSTRACT FROM AUTHOR]

A machine learning model for accurate and quick classification of tectonic and nontectonic earthquakes is proposed. Firstly, an improved method is proposed for detection of first arrivals. An iterative approach is applied for the multiwindow algorithm to decrease its computational cost, then a new method for detection of first arrivals is proposed by combining the improved multiwindow algorithm with a recursive least-squares filter and the Akaike information criterion. Secondly, it is shown that the integrated learning algorithm is a suitable method for classification, then four suitable features are manually selected to train it. Thirdly, the three parameter values of the integrated learning model are determined to improve its accuracy. Finally, based on seismic data from the China Earthquake Networks Center, simulations are conducted to test the validity of the proposed method for detection of first arrivals, then the classification accuracy is tested. The results show an accuracy of the model of 88.88%, indicating effective classification performance. [ABSTRACT FROM AUTHOR]

Although a large number of surface electromyography (sEMG) features have been proposed to improve hand gesture recognition accuracy, it is still hard to achieve acceptable performance in inter-session and inter-subject tests. To promote the application of sEMG-based human machine interaction, a convolutional neural network based feature extraction approach (CNNFeat) is proposed to improve hand gesture recognition accuracy. A sEMG database is recorded from eight subjects while performing ten hand gestures. Three classic classifiers, including linear discriminant analysis (LDA), support vector machine (SVM) and K nearest neighbor (KNN), are employed to compare the CNNFeat with 25 traditional features. This work concentrates on the analysis of CNNFeat through accuracy, safety index and repeatability index. The experimental results show that CNNFeat outperforms all the tested traditional features in inter-subject test and is listed as the best three features in inter-session test. Besides, it is also found that combining CNNFeat with traditional features can further improve the accuracy by 4.35%, 3.62% and 4.7% for SVM, LDA and KNN, respectively. Additionally, this work also demonstrates that CNNFeat can be potentially enhanced with more data for model training. [ABSTRACT FROM AUTHOR]

The regeneration mechanism of sulfated Cu/SAPO-34 catalysts in reducing atmospheres (5% H2/Ar and NH3/Ar at 600 °C) was investigated by using a series of characterization methods. Hydrogen regeneration improved the catalysts' NH3-SCR activity from 150 to 550 °C remarkably, while ammonia regeneration exhibited relatively less obvious promotion effect. The TPR of hydrogen and EPR spectra data show that the regeneration process affects the amount and the coordination of the active isolated Cu2+ species significantly. The desulfation increases the amount of isolated copper ions and improves the catalytic activity of SCR. [ABSTRACT FROM AUTHOR]

Compact molecular packing with short π-π stacking and large π-overlap in organic semiconductors is desirable for efficient charge transport and high carrier mobility. Thus charge transport anisotropy along different directions is commonly observed in organic semiconductors. Interestingly, in this article, we found that comparable charge transport property were achieved based on the single crystals of a bis-fused tetrathiafulvalene derivative (EM-TTP) compound along two interaction directions, that is, the multiple strong S···S intermolecular interactions and the π-π stacking direction, with the measured electrical conductivity and hole mobility of 0.4 S cm, 0.94 cm V s and 0.2 S cm−1, 0.65 cm V s, respectively. This finding provides us a new molecular design concept for developing novel organic semiconductors with isotropic charge transport property through the synergistic effect of multiple intermolecular interactions (such as S···S interactions) and π-π stacking. [ABSTRACT FROM AUTHOR]

The limestone forest of Mt. Exianling on Hainan Island, China, was inventoried, and their floristic composition and biogeographical affinities discussed. Botanical surveys recorded 1121 vascular plant species belonging to 620 genera and 171 families; of which 81 represented significant records including 11 new species. Mt. Exianling is characterized by phanerophytes making up ca. 79% of the total flora, and those with mesophyllous leaves comprising ca. 64%. Ecological species groups were discerned from field observations: species exclusive to limestone habitats make up 2.4% of the total flora. Based on their distributions, 11 biogeographic elements at the generic level are recognized. Our work on Mt. Exianling revealed closer affinity to tropical Asian floras than to temperate elements of eastern Asian floras, with ca. 90% of the seed plant genera being tropical; this limestone forest is essentially tropical and is part of the tropical Asian flora at its northern margin. Unfortunately, Exianling has been subject to environmental threats from mining activities in the past two decades. Kadoorie Conservation China has heavily involved in the conservation of Exianling limestone forest and partially financed the above floristic studies. A nature reserve station was constructed in 2009, and now Exianling is being gazetted as a formal provincial nature reserve. Recently, activities in exploiting of the gold mining in Exianling has been stopped by the nature reserve. [ABSTRACT FROM AUTHOR]

Grinding is the main process step for the high-precision optical components, and its process parameters may bring forth subsurface damage to some degrees on the surfaces and finally result in the variation of the mechanical and optical properties of the components. In this paper, the ground sample is etched to expose the micro cracks and the characterization parameters of the subsurface damage are extracted using the image processing method. To investigate the influence of main grinding parameters on the micro cracks of subsurface damage, relationships among the average abrasive size, grinding force, wheel speed, and grinding depth and characterization parameters (length, angle, and density) of micro cracks are established. The results show that the influence of grinding parameters on the micro crack's length is consistent with that on the surface roughness. The average abrasive size and grinding force have obvious influence on the subsurface damage and surface roughness than wheel speed and grinding depth. Micro cracks' angle and density are almost not affected by the grinding parameters. [ABSTRACT FROM AUTHOR]

Dayaoshania cotinifolia W. T. Wang is a rare and endangered member of the Gesneriaceae family which is endemic to China. To conserve this species, an efficient in vitro propagation and regeneration system via shoot organogenesis was established from young leaf explants. Adventitious shoot induction was possible within 50-60 d on basal Murashige and Skoog medium supplemented with 1-3 μM 6-benzyladenine, although 5 μM 6-benzyladenine induced hyperhydricity. Basal medium containing 1-5 μM thidiazuron induced fewer shoots, while 1-5 μM α-naphthaleneacetic acid induced numerous adventitious roots and a few adventitious shoots. However, when thidiazuron and α-naphthaleneacetic acid were combined, both the induction percentage and number of shoots increased. Leaf explants cultured on induction medium supplemented with 1-5 μM 2,4-dichlorophenoxyacetic acid become necrotic and died. Induction medium supplemented with 1 μM α-naphthaleneacetic acid and 1-3 μM 6-benzyladenine was optimal for inducing adventitious shoots as was the combination of 1-3 μM thidiazuron and 1 μM α-naphthaleneacetic acid. Induction medium containing 2.0 μM 6-benzyladenine and 0.5 μM indole-3-acetic acid was optimal for the multiplication of adventitious shoots. Rooting was achieved on half-strength MS medium supplemented with 3.0 μM indole-3-acetic acid or α-naphthaleneacetic acid and 0.1% activated charcoal. Plantlets were transplanted to a mixture of sand, vermiculite, and humus (1:1:1); 92% survived. This protocol is a unique and effective means to micropropagate this rare and important plant and could serve as a solution for in vitro and ex vitro conservation. [ABSTRACT FROM AUTHOR]

We investigated the effects of major environmental drivers associated with urbanization on species diversity and plant functional traits (PFTs) in the remnant subtropical evergreen broad-leaved forests in Metropolitan Guangzhou (Guangdong, China). Twenty environmental factors including topography, light, and soil properties were used to quantify the effects of urbanization. Vegetation data and soil properties were collected from 30 400-m plots at 6 study sites in urban and rural areas. The difference of plant species diversity and PFTs of remnant forests between urban and rural areas were analyzed. To discern the complex relationships, multivariate statistical analyses (e.g., canonical correspondence analysis and regression analysis) were employed. Pioneer species and stress-tolerant species can survive and vigorously establish their population dominance in the urban environment. The native herb diversity was lower in urban forests than in rural forests. Urban forests tend to prefer the species with Mesophanerophyte life form. In contrast, species in rural forests possessed Chamaephyte and Nanophanerophyte life forms and gravity/clonal growth dispersal mode. Soil pH and soil nutrients (K, Na, and TN) were positively related to herb diversity, while soil heavy metal concentrations (Cu) were negatively correlated with herb diversity. The herb plant species diversity declines and the species in the remnant forests usually have stress-tolerant functional traits in response to urbanization. The factors related to urbanization such as soil acidification, nutrient leaching, and heavy metal pollution were important in controlling the plant diversity in the forests along the urban-rural gradients. Urbanization affects the structure and functional traits of remnant subtropical evergreen broad-leaved forests. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen (N) deposition in subtropical metropolitan regions has increased greatly because of rapid urbanization, and such increase could lead to N-related changes in soil properties and plant diversity in remnant forests of urban ecosystems. To investigate the pattern of atmospheric N deposition along an urban-rural gradient in metropolitan Guangzhou, southern China, and to assess the potential influence of N deposition on soil properties and understory plant diversity in remnant forests, precipitation, and soil samples were collected and vegetation was surveyed from four forest sites between March 2010 and March 2011. The atmospheric inorganic nitrogen deposition (DIN) decreased with increasing distance from the urban center: DIN inputs were 43.3, 41.2, 35.2, and 30.1 kg N ha year in two urban sites, a suburban site and a rural site, respectively. However, forest soil N status (NH-N, NO-N, and total nitrogen) showed the opposite pattern. Understory herb-layer diversity was negatively correlated to DIN input and positively correlated to soil calcium (Ca) and potassium (K) concentrations and pH; with highest herb-layer diversity found in the rural site receiving the lowest amount of DIN input. These results indicated that higher DIN along with soil acidification and leaching of base cations (Ca and K) might change the current N status and increase nutrients leaching and thereby cause reductions in understory plant diversity. A regional policy linking atmospheric pollution and land protection is needed to protect the most N-sensitive herb species (e.g., forbs and ferns) in these remnant forests. [ABSTRACT FROM AUTHOR]

In this paper, an efficient two-step convolutional neural network (CNN) procedure is proposed to estimate earthquake magnitude using raw waveform data up to only 4 s after the P wave onset. In the proposed procedure, magnitude estimation is split into classification task and regression task. The classification task trains a CNN model to estimate the magnitude range by employing unsure responses that represent the classification decision boundary. In addition, the regression task trains two CNN models to estimate the specific magnitudes of large and small earthquakes, respectively. After training, the classification model achieves an accuracy of 98.63%. The mean absolute error (MAE) of the large earthquake regression and the small earthquake regression models are 0.26 and 0.46, respectively. The ideology behind the two-step procedure effectively address two main issues in earthquake early warning (EEW) systems: reducing missed alert caused by seismometer saturation and improving the accuracy of estimating specific magnitudes. Currently, this procedure has been connected to China Earthquake Networks Center (CENC) for real-time monitoring. [ABSTRACT FROM AUTHOR]

Plant phenology is sensitive to climate change; the timing of flowering has served as a visible indicator of plant phenology in numerous studies. The present study used phenological records from a manual monitoring program to characterize the flowering phenology of 12 species in Guia Hill, Macao. The mean peak flowering dates (PFDs) of these species ranged from March to September, 41.7% of which occurred in May. The earliest or latest PFDs of nine species occurred in 2013, a year with extremely heavy rain events in early spring. In addition, we found that, in the 5-year period, the monthly mean temperature or monthly precipitation in two periods, specifically 1) during November to December of the previous year and 2) during 0-2 months before the PFDs of each species, were significantly correlated with the PFD of eight species. The result showed that, even though complex species-specific responses to the characteristics of climate widely exist, most species in the present study responded to shifts in climate shifts in these two periods. In addition, some species were extraordinarily sensitive to extreme climate events. Precipitation was more effective in altering flowering date than temperature, especially among the late-flowering species in Guia Hill, Macao. [ABSTRACT FROM AUTHOR]

Understanding how the discharge-rate and the hydraulic gradient of a karst aquifer varies in response to rainfall events is important for the efficient management of water resources in these aquifers. The relationship between discharge and hydraulic gradient is related to aquifer properties such as the physical characteristics of the karstic matrix, hydraulic conductivity and the extent to which water is exchanged between conduits and the matrix. In this study, discharge and hydraulic gradient data were monitored at 4-h intervals for 476 continuous days in the Zhaidi karst aquifer located in Guilin, Guangxi Province, China. These data showed that the relationship between flow rate and hydraulic gradient in the aquifer became increasing non-linear with increasing flow rates. After analyzing the time series data, a hydrodynamic threshold between quickflow- and baseflow conditions was found to take place at a discharge rate of 0.80 m3/s. The linear law and nonlinear equations were obtained between discharge and hydraulic gradient which reflected the flow mechanism of groundwater flow in this karst aquifer. [ABSTRACT FROM AUTHOR]