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As one of the most important techniques for hyperspectral image dimensionality reduction, band selection has received considerable attention, whereas self-representation subspace clustering-based band selection algorithms have received quite a lot of attention with good effect. However, many of them lack the self-supervision of representations and ignore the multi-level spectral–spatial information of HSI and the connectivity of subspaces. To this end, this paper proposes a novel self-supervised multi-level representation learning fusion-based maximum entropy subspace clustering (MLRLFMESC) method for hyperspectral band selection. Firstly, to learn multi-level spectral–spatial information, self-representation subspace clustering is embedded between the encoder layers of the deep-stacked convolutional autoencoder and its corresponding decoder layers, respectively, as multiple fully connected layers to achieve multi-level representation learning (MLRL). A new auxiliary task is constructed for multi-level representation learning and multi-level self-supervised training to improve its capability of representation. Then, a fusion model is designed to fuse the multi-level spectral–spatial information to obtain a more distinctive coefficient matrix for self-expression, where the maximum entropy regularization (MER) method is employed to promote connectivity and the uniform dense distribution of band elements in each subspace. Finally, subspace clustering is conducted to obtain the final band subset. Experiments have been conducted on three hyperspectral datasets, and the corresponding results show that the proposed MLRLFMESC algorithm significantly outperforms several other band selection methods in classification performance. [ABSTRACT FROM AUTHOR]

The MADS-box family, a substantial group of plant transcription factors, crucially regulates plant growth and development. Although the functions of AGL12-like subgroups have been elucidated in Arabidopsis, rice, and walnut, their roles in grapes remain unexplored. In this study, we isolated VvAGL12, a member of the grape MADS-box group, and investigated its impact on plant growth and biomass production. VvAGL12 was found to localize in the nucleus and exhibit expression in both vegetative and reproductive organs. We introduced VvAGL12 into Arabidopsis thaliana ecotype Columbia-0 and an agl12 mutant. The resulting phenotypes in the agl12 mutant, complementary line, and overexpressed line underscored VvAGL12's ability to promote early flowering, augment plant growth, and enhance production. This was evident from the improved fresh weight, root length, plant height, and seed production, as well as the reduced flowering time. Subsequent transcriptome analysis revealed significant alterations in the expression of genes associated with cell-wall modification and flowering in the transgenic plants. In summary, the findings highlight VvAGL12′s pivotal role in the regulation of flowering timing, overall plant growth, and development. This study offers valuable insights, serving as a reference for understanding the influence of the VvAGL12 gene in other plant species and addressing yield-related challenges. [ABSTRACT FROM AUTHOR]

Understanding the accumulation characteristics of heavy metals in the growth process of American ginseng can provide theoretical support for its safe production. In this study, the content of Cu, Mn, As, Pb, Cd, Cr, and Ni in American ginseng (annual, biennial, and triennial) and planting soil were determined using inductively coupled plasma mass spectrometry (LCP-MS). In addition, the change in the content of these heavy metals in American ginseng was evaluated after soaking the plant for various time periods. The results indicated that the content of some heavy metals in American ginseng was correlated with soil heavy metal contents. For example, Ni, Cd, and Mn content in American ginseng was significantly negatively correlated with Ni content in soil. American ginseng exhibited distinct heavy metal accumulation characteristics in different parts at different growth stages. For example, in annual American ginseng, Mn and As are mainly enriched in lateral roots and taproots, while in biennial and triennial American ginseng, they are mainly enriched in reed heads. When American ginseng plant was soaked for various time intervals, its heavy metal content changed to varying degrees. In general, after soaking American ginseng for 30 min, the content of most heavy metals decreased. [ABSTRACT FROM AUTHOR]

Hyperspectral imaging (HSI) has emerged as a promising, advanced technology in remote sensing and has demonstrated great potential in the exploitation of a wide variety of data. In particular, its capability has expanded from unmixing data samples and detecting targets at the subpixel scale to finding endmembers, which generally cannot be resolved by multispectral imaging. Accordingly, a wealth of new HSI research has been conducted and reported in the literature in recent years. The aim of this Special Issue "Advances in Hyperspectral Data Exploitation" is to provide a forum for scholars and researchers to publish and share their research ideas and findings to facilitate the utility of hyperspectral imaging in data exploitation and other applications. With this in mind, this Special Issue accepted and published 19 papers in various areas, which can be organized into 9 categories, including I: Hyperspectral Image Classification, II: Hyperspectral Target Detection, III: Hyperspectral and Multispectral Fusion, IV: Mid-wave Infrared Hyperspectral Imaging, V: Hyperspectral Unmixing, VI: Hyperspectral Sensor Hardware Design, VII: Hyperspectral Reconstruction, VIII: Hyperspectral Visualization, and IX: Applications. [ABSTRACT FROM AUTHOR]

Glutathione S-transferases (GSTs) play an essential role in plant cell detoxification and secondary metabolism. However, their accurate functions in the growth and response to abiotic stress in woody plants are still largely unknown. In this work, a Phi class Glutathione S-transferase encoding gene PtGSTF1 was isolated from poplar (P. trichocarpa), and its biological functions in the regulation of biomass production and salt tolerance were investigated in transgenic poplar. PtGSTF1 was ubiquitously expressed in various tissues and organs, with a predominant expression in leaves and inducible expression by salt stress. Transgenic poplar overexpressing PtGSTF1 showed improved shoot growth, wood formation and improved salt tolerance, consistent with the increased xylem cell number and size under normal condition, and the optimized Na+ and K+ homeostasis and strengthened reactive oxygen species scavenging during salt stress. Further transcriptome analyses demonstrated that the expressions of genes related to hydrolase, cell wall modification, ion homeostasis and ROS scavenging were up- or down-regulated in transgenic plants. Our findings imply that PtGSTF1 improves both biomass production and salt tolerance through regulating hydrolase activity, cell wall modification, ion homeostasis and ROS scavenging in transgenic poplar, and that it can be considered as a useful gene candidate for the genetic breeding of new tree varieties with improved growth under salt stress conditions. [ABSTRACT FROM AUTHOR]

Individuals' gender development is influenced by the characteristics of personal and contextual environments. However, the role of sibling contexts in shaping gender norms has rarely been studied among Chinese youth at early adolescence as most of them were the only child. The aim of this paper is to compare perceived gender norms among adolescents aged 10–14 with different sibling configurations, to help inform and tailor guidance for sexual and reproductive health education in the future. We used the Global Early Adolescent Study baseline data collected from Shanghai, China. The sample for analysis was 1615 students. We used univariate analysis and multivariate ordinal logistic regression to compare perceived gender-stereotyped traits and gender role attitudes, stratified by age and sex. The results showed that sibling context was more influential for boys than girls at early adolescence in their gender socialization process. Among boys those who were with mixed-sex siblings scored higher on gender-stereotyped traits (ORonly-childvs. mixed-sex siblings = 0.67, 95% CI: 0.48–0.94, p = 0.019; ORsame-sex siblingsvs. mixed-sex siblings = 0.59, 95% CI: 0.37–0.96, p = 0.033). Younger early adolescents aged 10–12 who were the only child or who had mixed-sex siblings perceived more traditional gender role attitudes than those living with same-sex siblings (ORonly-childvs. same-sex siblings = 1.71, 95% CI: 1.06–2.75, p = 0.028; ORmixed-sex siblingsvs. same-sex siblings = 1.74, 95% CI: 1.03–2.94, p = 0.037). Comprehensive sexuality education with gender and power components being well addressed, both in and out of the family, is needed to provide extra gender-inclusive and gender-egalitarian environments for youth. [ABSTRACT FROM AUTHOR]

A type VI secretion system (T6SS) gene cluster has been reported in Acidovorax citrulli. Research on the activation conditions, functions, and the interactions between key elements in A. citrulli T6SS is lacking. Hcp (Hemolysin co-regulated protein) is both a structural protein and a secretion protein of T6SS, which makes it a special element. The aims of this study were to determine the role of Hcp and its activated conditions to reveal the functions of T6SS. In virulence and colonization assays of hcp deletion mutant strain Δhcp, tssm (type VI secretion system membrane subunit) deletion mutant strain Δtssm and double mutant ΔhcpΔtssm, population growth was affected but not virulence after injection of cotyledons and seed-to-seedling transmission on watermelon. The population growth of Δhcp and Δtssm were lower than A. citrulli wild type strain Aac5 of A. citrulli group II at early stage but higher at a later stage. Deletion of hcp also affected growth ability in different culture media, and the decline stage of Δhcp was delayed in KB medium. Biofilm formation ability of Δhcp, Δtssm and ΔhcpΔtssm was lower than Aac5 with competition by prey bacteria but higher in KB and M9-Fe3+ medium. Deletion of hcp reduced the competition and survival ability of Aac5. Based on the results of Western blotting and qRT-PCR analyses, Hcp is activated by cell density, competition, ferric irons, and the host plant. The expression levels of genes related to bacterial secretion systems, protein export, and several other pathways, were significantly changed in the Δhcp mutant compared to Aac5 when T6SS was activated at high cell density. Based on transcriptome data, we found that a few candidate effectors need further identification. The phenotypes, activated conditions and transcriptome data all supported the conclusion that although there is only one T6SS gene cluster present in the A. citrulli group II strain Aac5, it related to multiple biological processes, including colonization, growth ability, competition and biofilm formation. [ABSTRACT FROM AUTHOR]

Gender dissatisfaction is often linked to adverse health outcomes and is an under-researched area of adolescent health. The aim of our study was to examine the associations of gender dissatisfaction with adolescent mental distress and sexual victimization. We conducted a cross-sectional study in April 2019 using a computerized self-administered questionnaire to collect data on the gender dissatisfaction, mental distress, and sexual victimization among Chinese adolescents. We used multivariate logistic models to estimate sex-stratified adjusted odds ratios (AORs) and 95% confidence intervals (CIs) for the associations of gender dissatisfaction with mental distress and sexual victimization. Our study involved 538 female and 556 male students from grades 7 to 11. Among the female students, gender dissatisfaction was significantly associated with depression (AOR, 2.04, 95%CI, 1.17–3.58), anxiety (AOR, 2.13, 95%CI, 2.00–2.27), suicidal ideation (AOR, 2.36, 95%CI, 2.02–2.76), sexting victimization (AOR, 1.67, 95%CI, 1.11–2.51), and nonphysical sexual harassment (AOR, 1.72, 95%CI, 1.08–2.76). Among the male students, gender dissatisfaction was significantly associated with oral-–genital contact (AOR, 5.86, 95%CI, 2.74–12.54), attempted sexual assault (AOR, 9.63, 95%CI, 6.91–13.42), and completed sexual assault (AOR, 14.71, 95%CI, 1.16–187.33). Our findings suggest gender dissatisfaction is associated with adolescent mental distress and sexual victimization, underscoring the importance of implementing comprehensive sexual education with gender perspectives in China. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the associations between sexual-related knowledge, access to school and family sexuality education, and the experience of sexual intercourse, in order to make recommendations on sexuality education for vocational secondary school students in China. Methods: A cross-sectional study was conducted among 3180 vocational secondary school students in the Shanghai municipality and the Shaanxi province, China. Data were collected through an online, electronic questionnaire, which included socio-demographics, sexual-related knowledge, sources of information, and sexual-related behaviors. Results: The score on sexual-related knowledge among girls (53.8) is higher than that of boys (48.8), and that of participants from Shanghai (55.2) is higher than their counterparts from Shaanxi (47.6). The proportions of girls (70% and 41.7%, respectively) and participants from Shanghai (65% and 35.7%, respectively) who reported acquiring sexual information from their schools/teachers and parents are higher than that of boys (54.3% and 21.0%, respectively) and their counterparts from Shaanxi (59.7% and 27.4%, respectively). About 6% of participants had experienced sexual intercourse and 10% had watched porn actively. Experience of sexual intercourse was associated with higher sexual-related knowledge scores (OR = 1.01, 95% CI: 1.00–1.02) and active porn watching (OR = 2.63, 95% CI: 1.79–3.84) but was not associated with school and family sexuality education. Conclusions: Vocational secondary school students had poor sexual knowledge and inadequate school and family sexuality education. School and family-based comprehensive sexuality education should be promoted among vocational secondary school students. [ABSTRACT FROM AUTHOR]

This paper develops a new approach to band subset selection (BSS) for hyperspectral image classification (HSIC) which selects multiple bands simultaneously as a band subset, referred to as simultaneous multiple band selection (SMMBS), rather than one band at a time sequentially, referred to as sequential multiple band selection (SQMBS), as most traditional band selection methods do. In doing so, a criterion is particularly developed for BSS that can be used for HSIC. It is a linearly constrained minimum variance (LCMV) derived from adaptive beamforming in array signal processing which can be used to model misclassification errors as the minimum variance. To avoid an exhaustive search for all possible band subsets, two numerical algorithms, referred to as sequential (SQ) and successive (SC) algorithms are also developed for LCMV-based SMMBS, called SQ LCMV-BSS and SC LCMV-BSS. Experimental results demonstrate that LCMV-based BSS has advantages over SQMBS. [ABSTRACT FROM AUTHOR]

The fusion of a hyperspectral image (HSI) and multispectral image (MSI) can significantly improve the ability of ground target recognition and identification. The quality of spatial information and the fidelity of spectral information are normally contradictory. However, these two properties are non-negligible indicators for multi-source remote-sensing images fusion. The smoothing filter-based intensity modulation (SFIM) method is a simple yet effective model for image fusion, which can improve the spatial texture details of the image well, and maintain the spectral characteristics of the image significantly. However, traditional SFIM has a poor effect for edge information sharpening, leading to a bad overall fusion result. In order to obtain better spatial information, a spatial filter-based improved LSE-SFIM algorithm is proposed in this paper. Firstly, the least square estimation (LSE) algorithm is combined with SFIM, which can effectively improve the spatial information quality of the fused image. At the same time, in order to better maintain the spatial information, four spatial filters (mean, median, nearest and bilinear) are used for the simulated MSI image to extract fine spatial information. Six quality indexes are used to compare the performance of different algorithms, and the experimental results demonstrate that the LSE-SFIM based on bilinear (LES-SFIM-B) performs significantly better than the traditional SFIM algorithm and other spatially enhanced LSE-SFIM algorithms proposed in this paper. Furthermore, LSE-SFIM-B could also obtain similar performance compared with three state-of-the-art HSI-MSI fusion algorithms (CNMF, HySure, and FUSE), while the computing time is much shorter. [ABSTRACT FROM AUTHOR]

Arabidopsis trichome is specialized structure that develops from epidermal cells, and is an excellent model system for studying various aspects of plant cell development and cell differentiation. Our previous studies have shown that C2H2 zinc finger protein family genes, including GIS, GIS2, GIS3, ZFP5, ZFP6 and ZFP8, play an important role in controlling trichome initiation in Arabidopsis. Here, our novel results showed a C2H2 zinc finger protein, ZFP1, which also plays an important role in trichome initiation in Arabidopsis. ZFP1 over-expression lines display significantly increased trichome number on cauline leaves, lateral branches and main stems in comparison with wild type plants. ZFP1 RNAi lines and loss-of-function mutants showed the opposite phenotype. Furthermore, our study also found that ZFP1 mediates the regulation of trichome initiation by cytokinin signaling. The molecular and genetic analyses reveal that ZFP1 acts upstream of key trichome initiation factors, GL3 and TRY. [ABSTRACT FROM AUTHOR]

A new sintering method, namely ultrasonic assisted sintering (UAS), has been proposed using mechanical heat converted from high frequency motion between particles. Pure aluminum specimens with diameter of 5 mm and thickness of ~2 mm have been successfully sintered in two seconds. Based on the thermodynamic analysis, the underlying heating mechanism is quantitatively interpreted, which involves high-frequency interparticle friction and plastic deformation driven by ultrasonic squeezing. Consequently, temperature rises rapidly at a speed of about 300 K/s, and the maximum temperature reaches up to 0.9 times of melting point of the aluminum during UAS. The sintered specimens have a high density of dislocations, under the combined effects of dislocations and undulating stress field, volume diffusion coefficient for sintering increases by several orders of magnitude, therefore, rapid densification can be accomplished in seconds. In addition, the sintered aluminum has ultrahigh nanohardness (~1.13 GPa), which can be attributed to the hierarchical structure formed during UAS process. [ABSTRACT FROM AUTHOR]

Forming complex geometries using the casting process is a big challenge for bulk metallic glasses (BMGs), because of a lack of time of the window for shaping under the required high cooling rate. In this work, we open an approach named the "entire process vacuum high pressure die casting" (EPV-HPDC), which delivers the ability to fill die with molten metal in milliseconds, and create solidification under high pressure. Based on this process, various Zr-based BMGs were prepared by using industrial grade raw material. The results indicate that the EPV-HPDC process is feasible to produce a glassy structure for most Zr-based BMGs, with a size of 3 mm × 10 mm and with a high strength. In addition, it has been found that EPV-HPDC process allows complex industrial BMG parts, some of which are hard to be formed by any other metal processes, to be net shaped precisely. The BMG components prepared by the EVP-HPDC process possess the advantages of dimensional accuracy, efficiency, and cost compared with the ones formed by other methods. The EVP-HPDC process paves the way for the large-scale application of BMGs. [ABSTRACT FROM AUTHOR]