Chimonanthus praecox is a traditional ornamental tree in China, flowering in winter at low temperature, which may have its unique molecular mechanism of flower opening and senescence. However, there is limited research on the molecular network regulatory mechanisms underlying the C. praecox flower senescence. Research showed that WRKY family is one of the largest transcription factors regulating senescence. In this study, 74 CpWRKY family members were identified in C.praecox var. Concolor genome. Based on the WRKY family gene profile during flower opening and senescence using the transcriptome database, the expression of 31 CpWRKYs was significantly induced during flower senescence. Among them, the expression of CpWRKY54 was significantly affected by flower senescence and specifically induced by low temperature. Additionally, the inducibility of CpWRKY54 promoter activity was consistent with the pattern of gene expression. Moreover, the overexpression of CpWRKY54 in petunia significantly accelerated the flower senescence. The yeast two-hybrid and bimolecular fluorescence complementation showed the CpWRKY54 interacted with a MADS-box gene, AGAMOUS-LIKE 29 (CpAGL29), while the yeast one-hybrid. dual-luciferase reporter assays and electrophoretic mobility shift assay (EMSA) showed that CpAGL29 is an upstream regulatory protein of CpWRKY42. Overexpression of CpWRKY42 also accelerated the flower senescence in transgenic petunia. The potential downstream genes, including autophagy- and senescence-associated genes containing W-box elements in their promoters that maybe related to flower senescence, and can be regulated by CpWRKY54 and CpWRKY42, were also identified from the genome. This transcription regulatory network provides new insights into the molecular mechanism underlying C. praecox flower longevity during winter.

Ancient introgression is an infrequent evolutionary process often associated with conflicts between nuclear and organellar phylogenies. Determining whether such conflicts arise from introgression, incomplete lineage sorting (ILS), or other processes is essential to understanding plant diversification. Previous studies have reported phylogenetic discordance in the placement of Xanthoceras, but its causes remain unclear. Here, we analyzed transcriptome data from 41 Sapindaceae samples to reconstruct phylogenies and investigate this discordance. While nuclear phylogenies consistently placed Xanthoceras as sister to subfam. Hippocastanoideae, plastid data positioned it as the earliest-diverging lineage within Sapindaceae. Our coalescent simulations suggest that this cyto-nuclear discordance is unlikely to be explained by ILS alone. HyDe and PhyloNet analyses provided strong evidence that Xanthoceras experienced ancient introgression, incorporating approximately 16% of its genetic material from ancestral subfam. Sapindoideae lineages. Morphological traits further support this evolutionary history, reflecting characteristics of both contributing subfamilies. Likely occurring during the Paleogene, this introgression represents a rare instance of cross-subfamily gene flow shaping the evolutionary trajectory of a major plant lineage. Our findings clarify the evolutionary history of Xanthoceras and underscore the role of ancient introgression in driving phylogenetic conflicts, offering a rare example of introgression-driven diversification in angiosperms.

Genetic diversity in endangered species is of special significance in the face of escalating global climate change and alarming biodiversity declines. Rhododendron platypodum Diels, an endangered species endemic to China, is distinguished by its restricted geographical range. This study aimed to explore genetic diversity and differentiation among its populations, gathering samples from all four distribution sites: Jinfo Mountain (JFM), Zhaoyun Mountain (ZYM), Baima Mountain (BMM), and Mao’er Mountain (MEM). We employed 18 pairs of Simple Sequence Repeat (SSR) primers to ascertain the genetic diversity and structural characteristics of these samples and further utilized 19 phenotypic data points to corroborate the differentiation observed among the populations. These primers detected 52 alleles, with the average number of observed alleles (Na) being 2.89, the average number of effective alleles (Ne) being 2.12, the average observed heterozygosity (Ho) being 0.57, and the expected heterozygosity (He) being 0.50. This array of data demonstrates the efficacy of the primers in reflecting R. platypodum’s genetic diversity. SSR-based genetic analysis of the populations yielded Ho, He, and Shannon index (I) values ranging from 0.47 to 0.65, 0.36 to 0.46, and 0.53 to 0.69, respectively. Notably, the ZYM population emerged as the most genetically diverse. Further analysis, incorporating molecular variance, principal component analysis, UPGMA cluster analysis, and structure analysis, highlighted significant genetic differentiation between the Chongqing (BMM, JFM, ZYM) and Guangxi (MEM) populations. Morphological data analysis corroborated these findings. Additionally, marked genetic and morphological distinctions were evident among the three Chongqing populations (BMM, JFM, and ZYM). This suggests that, despite the observed regional differentiation, R. platypodum’s overall genetic diversity is relatively constrained compared to other species within the Rhododendron genus. Consequently, R. platypodum conservation hinges critically on preserving its genetic diversity and protecting its distinct populations.

Vein-associated pigmentation (venation) is a type of floral coloration adopted by plants to attract pollinators. Several petunia (Petunia hybrida) lines generate dorsoventrally asymmetric venation patterning of the corolla tube, in which venation is only present in the dorsal tube. The molecular mechanism underlying this trait is unknown. Here, we demonstrate that miR319 is preferentially expressed in the dorsal corolla tube, leading to dorsoventrally asymmetric expression of its target genes. Transgenic lines overexpressing phy-miR319a generated uniform venation patterning of the corolla tube. Knockout of TCP genes targeted by miR319 promoted venation patterning in the ventral and dorsal tube, while overexpression of the miR319 target gene, PhTCP6, completely inhibited corolla tube venation patterning. In addition, miR319-targeted TCPs negatively regulated venation patterning, probably by repressing the regulator of venation patterning, AN4. Together, our data demonstrate that asymmetric expression of miR319 promotes venation patterning in the petunia dorsal tube alone by repressing the expression of its target TCP genes, which negatively regulate corolla tube venation patterning. These findings provide novel insights into how the dorsoventrally asymmetric distribution of venation patterning is established in zygomorphic flowers.

NAC (NAM, ATAF1/2, and CUC2) transcription factors regulate plant growth and development and response to various stresses. However, there is still limited insight into the NAC family in Chimonanthus praecox. This study performed a genome-wide characterization of the NAC transcription factor family members in C. praecox. A total of 105 NAC family members were identified from the C. praecox genome. The phylogenetic tree categorized the CpNACs into nine groups and the accuracy of this classification was confirmed by the analysis results of conserved motifs, conserved domain, and gene structure. Cis-acting element analysis revealed that the promoters of CpNACs were abundant in elements responsive to various hormones and stresses, implying the functional diversity and complexity of CpNACs. Furthermore, we investigated the function of the CpNAC30. The expression level of CpNAC30 could be significantly induced by abiotic stress and the CpNAC30 was the highest expressed in mature leaves of C. praecox. Overexpression of CpNAC30 reduced salt stress tolerance of transgenic Arabidopsis. Nevertheless, the drought stress tolerance of transgenic plants was enhanced. This study lays a foundation for further understanding the function of CpNACs genes and provides insights for abiotic stress tolerance breeding of C. praecox and other woody plants.

In this study, salicylhydroxamic acid (SHA) was added before the depressant dextrin during flotation process as a pre-adsorbent to pre-adsorb chlorite subordinating elements (Al) and hinder the subsequent adsorption of depressants on chlorite, which utilizing reverse flotation to separate specularite from chlorite and reveal the mechanisms behind it. Single-mineral flotation test results indicated that dextrin and starch have comparable depression effect, while dextrin exhibits better selectivity towards specularite than starch. Chlorite's high floatability can be maintained under the same experimental conditions by adding 9mg/L SHA and there is an effective separation achieved. Zeta potential data, FT-IR and X-ray photoelectron spectroscopy demonstrated that SHA forms four or five membered ring chelates with Al sites and a few Fe sites on the surface of chlorite through O-O bonding, which forms steric hindrance the adsorption of dextrin, and then forms electrostatic attraction with DDA to improve the floatability of chlorite. In addition, the active Fe sites on specularite surface were sufficiently depressed by dextrin, resulting in the selective separation of chlorite from specularite.

AbstractPassive source detection is a challenging problem in the shadow zone, where the sound is contributed primarily by bottom‐bounce rays. The conventional beamforming detector (CBFD), which utilises the sound energy from a single direction, suffers potential significant performance degradation in the multipath‐signal scenario. The matched field detector (MFD) offers optimal performance by exploiting full‐wave field characteristics but is limited due to its reliance on prior ocean environmental knowledge. The authors demonstrate that the incident sound on a near‐surface vertical line array in the shadow zone can be approximated as a coherent sum of two plane waves that share a symmetric arrival angle about the horizontal. This leads to the signal subspace depending only on the arrival angle, which the authors call the bottom‐bounce ray angle subspace (BRAS). With generalised likelihood ratio test theory, the authors further derive the BRAS detector (BRASD). It can utilise the full signal energy under the premise of weak environmental knowledge requirements and is generally superior to the CBFD. Simulation results in a typical deep‐water channel under different source‐position and array configuration conditions demonstrate the effectiveness of the BRASD and suggest that it can even offer a performance comparable to that of the MFD under specific conditions.

Different types of abiotic stress significantly affect plant growth and crop production even though plants have evolved complex responses to mitigate their effects. Some studies have shown that the GDSL (Gly-Asp-Ser-Leu) lipase proteins regulate the adaptation of plants to abiotic stresses. However, the functions of most GDSL lipases still remain unexplored in plants. To our knowledge, this study is the first to identify the GDSL lipase (GLIP) gene CpGLIP1 in Chimonanthus praecox, which is a hardy and important deciduous aromatic shrub that is native to China. CpGLIP1 was highly expressed in the young leaves and the sprout stage of flowers when there were easily damaged parts of C. praecox. Treatments of drought, cold, jasmonic acid, and gibberellic acid significantly increased the level of expression of CpGLIP1. Additionally, a β-glucuronidase histochemical analysis showed that the CpGLIP1 promoter activity was tissue-specific, and the inducibility of the CpGLIP1 promoter was consistent with the pattern of gene expression. Moreover, the overexpression of CpGLIP1 in Arabidopsis thaliana and poplar (Populus tremula×Populus alba) plants resulted in higher rates of growth and survival and better physiological indices than the wild-type (WT) plants after drought and cold treatment, which indicated that overexpression of CpGLIP1 improved tolerance to drought and cold. In addition, 22 upstream regulatory proteins were screened using a yeast one-hybrid (Y1H) system, and SRG (senescence-related gene) and HARBI1 (harbinger transposase derived 1) proteins were verified to bind the promoter region of CpGLIP1 gene, which suggests that their function is to enhance their regulation in drought and cold response by CpGLIP1. These findings comprehensively demonstrate the function of GDSL lipase in C. praecox. It also provides effective references to elucidate the potential molecular regulatory mechanism of GDSL lipases and provide candidate genes to improve the tolerance of crops, such as drought and cold stress, in future research.

Flotation is the most known beneficiation method for the separation of complex and refractory iron ores. As a typical iron-containing silicates, it is difficult to separate chlorite from specularite, because of the similar surface physicochemical properties. In this study, the selective depression effect of sodium hexametaphosphate (SHMP) was conducted via the cationic micro-flotation. The surface adsorption mechanism between SHMP and the two mineral surface was explored through surface adsorption amount tests, Zeta-potential measurements, Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses. The micro-flotation results indicated that SHMP could selectively depress around 90% of chlorite, while its effect on the floatability of specularite was negligible (<20% depressing). The surface adsorption amount tests, Zeta-potential measurements analysis demonstrated that SHMP selectively adsorb on chlorite surface while on the surface of specularite is feeble. The further surface adsorption analysis via FT-IR and XPS proved that SHMP selective adsorption occurred on the chlorite surface mainly by chemisorption mainly through the chelation reaction between O in the phosphate groups of SHMP molecular and metal ions on surface of chlorite.

In this paper, we focus on estimating output growth and its components attributed to quasi-fixed inputs, variable inputs, and productivity change, while treating variable inputs as endogenous. We consider two approaches. In the classical approach the time trend variable proxies for technical (productivity) change, while in the productivity (proxy variable) approach, we add a “productivity” term which is correlated with the variable inputs. Therefore, estimation strategies in the two models are different. Instead of using a Cobb–Douglas production function, we employ a translog production function to add flexibility. We showcase our theoretical results with Chinese manufacturing as an empirical exercise.

Members of the AP2 subfamily were identified at the whole genome level in Chimonanthus praecox,and their expression patterns during flower development were analyzed. The expression profile of CpAP2-L11 was investigated,and 35S::CpAP2-L11 was introduced into Arabidopsis thaliana Columbia-0（Col-0）to analyze its function. A total of 20 AP2 subfamily transcription factors were identified,including five,six,and nine members from the euAP2,basalANT,and euANT groups,respectively,and all members of the euAP2 group have no miR172 binding sites. Synteny analysis revealed that 12members form 16 pairs of duplicated genes,which were subject to purifying selection during the evolutionary process. Most AP2 subfamily members are highly expressed in April and May flower buds（FBs）,with low expression during the entire or later stage of the chilling requirement（CR）accumulation;the expression level of CpAP2-L11 increased significantly in FBs initiating blooming when CR accumulation reached 570 CU. qRT-PCR analysis indicated CpAP2-L11 was highly expressed in the young fruit,outer tepals,and stamens,but a low expression level was detected in stems and leaves in C.praecox. The expression level of CpAP2-L11 was downregulated by high-or low-temperature. Ectopic expression of CpAP2-L11 in Arabidopsis showed earlier bolting time and the relative expression of FT,SOC1,LFY and AP1 genes increased significantly. CpAP2-L11 probably participates in chilling-induced dormancy breaking and blooming in winter and FBs differentiation in spring in C. praecox,also promoting flowering in ectopic overexpression Arabidopsis.

To explore the flotation feasibility and flotation law of iron minerals from amphibole-type iron oxide ore with full-size minerals, a systematic study on the flotation behaviors of single minerals hematite, quartz, and amphibole was carried out with the anionic reverse flotation system. The effects of collectors, depressants, activators, and pH on the floatabilities of three single minerals was investigated. The flotation separations of binary mixed minerals and ternary mixed ores were carried out, respectively. The study results show that CaCl2 is adsorbed on the surfaces of quartz and amphibole, which can activate them. The hydroxyl groups of the starch molecular chain were adsorbed on the surfaces of the hematite and amphibole in the form of hydrogen bonds, but were hardly adsorbed on surface of the quartz. Therefore, both hematite and amphibole were depressed, resulting in a poor separation effect of the three single minerals in the anionic flotation system.

Abstract The plant MYB transcription factor family participates in growth, differentiation, metabolism, and biotic and abiotic stress responses. The functions of HbMYBs in rubber tree leaves remain to be elucidated. In this study, molecular biology, bioinformatics and plant pathology techniques were used to identify and analyze HbMYB gene family members in rubber tree leaves. According to the results, 31 members of the HbMYB gene family were identified in the rubber tree. They were divided into 10 subgroups and were characterized by 3 unique motifs, in which 25 HbMYB members have R2R3-MYB conserved structural domains. Expression analysis revealed that the members of the HbMYB family were mainly expressed in flowers. The expression of the S22 and S20 subgroups increased significantly in powdery mildew-infected leaves. The expression of 10 HbMYBs was significantly induced by ethylene treatment. These results provide fundamental knowledge for further studying the response of the HbMYB family to biotic and abiotic stresses in rubber tree.

Why should the producers be subsidized? What are the contributions and channels of subsidies in total factor productivity (TFP) and profitability changes? We address these in a novel way by decomposing TFP and profitability changes into technical change, scale economies, subsidies, input and output misallocations, and inefficiency. A battery of models is deployed to answer these questions, instead of using a single model as done in past studies. First, we use both parametric and nonparametric approaches and estimate them treating subsidies as either exogenous or endogenous. Second, we reexamine both approaches with and without inefficiency. Third, we check the robustness of results across different models using a panel of Norwegian farms. The empirical results show an overall increase of 2.3% per annum in profitability in which the subsidy, scale, and inefficiency components contributed, on average, positively. It is important to note that the magnitude of these components varies across models.

Using a unique dataset assembled from several sources, we examine the effects of democracy, corruption, and economic freedom on economic growth for over one hundred countries. To allow for heterogeneous effects, we use a quantile regression approach. Our results support some findings in the literature, but also provide some new conclusions. In many cases, quantile regression estimates are quite different from those from GMM. We find that the positive effect of democracy is lower for the countries with a higher growth rate of GDP per capita, which may sound counter-intuitive to conventional wisdom. Likewise, we find that corruption “sands the wheels” (“greases the wheels”) for the lowest (highest) GDP per capita growth countries. Economic freedom shows a positive effect on GDP per capita growth rate. Our results suggest that since democratic status is hard to change in the short run, certain current corruption control measures as well as economic freedom adjustment policies may be reconsidered, especially among the fastest and slowest growing countries.

This paper examines the effect of government subsidies on firm-level productivity. The subsidy-promoting policies are oftentimes justified on the ground that subsidies increase the recipient firms' innovation and productivity. We develop a novel (semiparametric) method to structurally identify the firm-level productivity in the presence of subsidies. Unlike previous studies, we assume that subsidies are endogenous. To correct for the endogeneity problem, we use a switching regression in our semiparametric production function. Our method provides an improved framework for estimating the production function with endogenous and/or censored variables. We apply our method to study the effect of subsidies on firmlevel productivity in the Chinese machinery industry, using panel data from 1998 to 2007. We find strong empirical evidence that subsidies have a positive effect on firms' persistent productivity. Subsidies may allow firms to invest more on research and development (R&D) and thus improve productivity. Using the available R&D data, we find evidence to support this explanation that more subsidies are associated with higher R&D investment. We also carry out a decomposition analysis to separately examine the subsidy effect on output via the input channel and the persistent productivity channel. Opposite effects are found from the two channels and overall subsidies have a positive effect on a firm's output. (c) 2022 Elsevier B.V. All rights reserved.

We consider detection of a source by a vertical line array (VLA) in shallow water: the source position is unknown and the environmental parameters (such as water depth) are known only in that they are within certain limits. The performances of familiar correlation detectors, e.g., generalized likelihood ratio, Bayesian, robust matched field processing detectors, can deteriorate markedly in some environment/source-position pairs. Previous work proposed a robust mode space detector, robust in the sense that the performance only depends on the signal-to-noise ratio and is insensitive to the unknown environmental and source-position specifics, with the mode space being spanned by VLA sampled modes (modal depth functions). However, only complete mode sampling was considered. Given that modes are generally incompletely sampled due to insufficient array aperture, robustness absent complete mode sampling is here investigated. We propose to use the physically supported greatest dimensional effective mode space to implement a robust subspace detector, as opposed to the original greatest dimensional one as before: the former is exactly the latter, but with nuisance modes rejected, thus leading to a better robust performance. The resulting greatest dimensional effective mode space detector (GE-MSD) suffers only light performance decreases relative to the correlation detectors’ performance peaks, and is much more computationally efficient. The effect of surface-generated noise on the GE-MSD’s robustness is numerically investigated. The results suggest that surface noise indeed degrades the GE-MSD’s robustness, but that incomplete mode sampling, which causes an approximate collinearity among sampled modes, can mitigate this.

光催化方法降解选矿废水中黄药是一种环境友好型的选矿废水处理工艺,具有操作简单方便、适用范围广、反应条件温和、无二次污染等优点.本工作以黄药为光催化降解对象,综述了近年来相关催化剂的研究进展,主要介绍了光催化剂的研究概况,根据光催化剂材料的差异及其改性方式的不同分类进行说明,其次基于影响光催化降解率的因素总结提出了改善方法,同时对光催化降解黄药的催化剂的设计及工艺开发进行了展望.

以96份来源于贵州、 湖南、 秦岭地区的三叶木通实生种质资源为材料,对其19个表型性状进行遗传多样性分析、 相关性分析、 主成分分析和聚类分析.结果表明,10个数量性状变异系数范围为12.9％～41.4％,9个质量性状的遗传多样性指数范围为0.59～1.85;通过相关分析可知,大部分性状之间都有显著相关性;主成分分析将表型性状整合为4个主成分,累积贡献率达到64.714％,第1主成分主要与果实性状有关,第2和第3主成分都主要与叶片长宽和形态有关,第4主成分主要与植株染病情况有关;聚类分析将96份资源划分为3个类群,第Ⅰ类为果实、 叶片较大的类群,第Ⅱ类为果实抗病性较强类群,第Ⅲ类为无果实着生、 株型疏散类群.综合分析三叶木通种质资源遗传多样性,为三叶木通种质资源的利用及品种选育等提供重要参考.

The effect of the dilution gas flow rate on inorganic oxide insulating layers can improve fluidised bed chemical vapour deposition (FBCVD) in Fe–Si/inorganic-oxide soft magnetic composites and obtain excellent magnetic properties. Herein, Fe–Si/SiO2 composite particles coated via FBCVD and deposited at a 125–350 mL/min Ar-dilution gas flow rate were prepared and sintered into soft magnetic composites. Results demonstrate that SiO2 deposited on the Fe–Si substrate particle surface changed from submicron SiO2 clusters (125 mL/min) to an incomplete SiO2 film, then to a complete SiO2 film, and finally to a porous SiO2 film as the Ar-dilution gas flow rate increased. SiO2 layers began to transform from the amorphous to the beta-cristobalite state with a hexagonal crystal structure between 1149.45 K and 1280.75 K. However, the SiO2 amorphous layers’ crystallisation did not affect the Fe–Si substrate particles’ crystal structure. With the increasing Ar-dilution gas flow rate, the saturation magnetisation of Fe–Si/SiO2 soft magnetic composites initially decreased and then increased. The electrical resistivity increased before 150 mL/min, followed by an increase between 150 and 250 mL/min and then decreased, whereas the total core loss exhibited the opposite trend. These results show that magnetic performance can be promoted by selecting a suitable dilution flow rate.