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The optimal combination of the nitrogen fertilizer application and planting density with reference to the silage maize yield and quality remains unclear. We hypothesized that increasing both would increase yields following the law of diminishing returns. Yayu26, a silage maize cultivar, was used in a split-plot experiment to investigate the effects of nitrogen fertilizer and planting density on growth, nutrient characteristics, and chlorophyll fluorescence. The main plots were assigned to three planting densities: 60,000 (A1), 75,000 (A2), and 90,000 (A3) plants hm−2, and the subplots were assigned to four nitrogen fertilizer rates: 0 (B1), 120 (B2), 240 (B3), and 360 (B4) kg hm−2. The results showed that increasing the nitrogen application rate and planting density both enhanced silage maize yield. Nitrogen accumulation and agronomic use efficiency peaked at a planting density of 75,000 hm−2. Structural equation modeling showed that the nitrogen application rate and planting density affected nitrogen accumulation and nutrient properties by influencing chlorophyll fluorescence parameters and nitrogen agronomic efficiency, ultimately resulting in a positive effect on the yield. The A3 × B2 treatments exhibited higher nitrogen accumulation, potentially compensating for any deficiencies in the dry-matter yield. Therefore, the A3 × B2 treatment was evaluated as the optimal treatment to achieve sustainable and economically feasible silage maize production. [ABSTRACT FROM AUTHOR]

Introduction: Lignin has great potential as the most abundant renewable phenolic polymer. Studies have shown that lignin structure varies depending on different sources and different extraction methods. However, there are few studies on lignin in kudzu root residue. Objectives: The aim of the study was to explore optimal extraction conditions of Pueraria lobata residue lignin (PLL) with deep eutectic solvents (DESs) and characterise the structure and morphology of PLL. Methods: Firstly, the chemical composition of kudzu root residue was determined by the Van‐soest method. Then, betaine was used as hydrogen bond acceptor (HBA), nine kinds of common acids and alcohol were selected as hydrogen bond donor (HBD) to synthesise a DES to extract lignin from kudzu root residue. The influence of conditions on the extraction of PLL was explored by a betaine‐based DES according to a single‐factor experiment, and then the best process of PLL extraction was determined by an orthogonal experiment. Finally, the morphology and structure of PLL were analysed by scanning electron microscope (SEM), thermogravimetric analysis (TGA), gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), and NMR. Results: Cellulose, hemicellulose, lignin, and ash content in kudzu root residue were 41.13%, 16.39%, 25.03%, and 0.41%, respectively. When the DES consisted of betaine and formic acid, the solid–liquid ratio was 1:45, the extraction time was 5.5 h at 160°C, the extraction yield of lignin was 89.29%, and the purity was 83.01%. PLL was composed of interconnected spherical particles with good thermal stability and narrow polydispersity index (PDI) distribution. FTIR and 2D‐heteronuclear singular quantum correlation (HSQC) NMR illustrated that PLL was a typical G‐type and S‐type lignin. Conclusion: This study would fill the gap of research on lignin in kudzu root residue and provide a theoretical reference for the utilisation of lignin in kudzu roots as well as a new thinking for the recycling of kudzu root resources. Deep eutectic solvents which composed of biomass‐based betaine and a variety of carboxylic acids, were investigated to extract lignin from kudzu roots. The single‐factor and orthogonal experiments were carried out using the extraction yield of lignin as the indicator to acquire the optimum conditions. Morphological and structural experiments data indicate that kudzu lignin is a SG‐type lignin with nano‐network. Kudzu lignin has medium molecular weight and small dispersion coefficient, all of which leads to the excellent physical and chemical stability. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to examine how father involvement and family relationships changed during the COVID‐19 lockdown and their relations to fathers' work arrangements. Background: The COVID‐19 pandemic has transformed how parents arrange their work and family in China and elsewhere. Many fathers, once working long hours at the workplace, had to adjust their work arrangements, working reduced hours or working from home. Method: This study used a mixed methods design. Participants were parents of preschool or school‐age children in China. In Study 1, 31 mothers were interviewed about the change in father involvement and family relationships during the COVID‐19 lockdown compared with pre‐COVID‐19. In Study 2, a sample of father–mother dyads (N = 637) completed survey measures of work arrangements, father involvement, and family relationships. Results: Study 1 suggested increased father involvement and improved family relationships amid the lockdown and highlighted the role of fathers' work. Study 2 revealed that fathers' changed work arrangements (i.e., working from home) were associated with higher father involvement and more positive family relationships during the lockdown. Father involvement may mediate the associations between fathers' work arrangements and father–child closeness as well as mothers' marital satisfaction. Conclusion and Implications: Working from home could promote involved fathering and stronger family relationships, strengthening the family's overall capacity to combat the stressors and challenges brought by the COVID‐19 pandemic. [ABSTRACT FROM AUTHOR]