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Premise: Previous work searching for sexual dimorphism has largely relied on the comparison of trait mean vectors between sexes in dioecious plants. Whether trait scaling (i.e., the ratio of proportional changes in covarying traits) differs between sexes, along with its functional significance, remains unclear. Methods: We measured 10 vegetative traits pertaining to carbon, water, and nutrient economics across 337 individuals (157 males and 180 females) of the diocious species Eurya japonica during the fruiting season in eastern China. Piecewise structural equation modeling was employed to reveal the scaling relationships of multiple interacting traits, and multivariate analysis of (co)variance was conducted to test for intersexual differences. Results: There was no sexual dimorphism in terms of trait mean vectors across the 10 vegetative traits in E. japonica. Moreover, most relationships for covarying trait pairs (17 out of 19) exhibited common scaling slopes between sexes. However, the scaling slopes for leaf phosphorus (P) vs. nitrogen (N) differed between sexes, with 5.6‐ and 3.0‐fold increases of P coinciding with a 10‐fold increase of N in male and female plants, respectively. Conclusions: The lower ratio of proportional changes in P vs. N for females likely reflects stronger P limitation for their vegetative growth, as they require greater P investments in fruiting. Therefore, P vs. N scaling can be a key avenue allowing for sex‐specific strategic optimization under unequal reproductive requirements. This study uncovers a hidden aspect of secondary sex character in dioecious plants, and highlights the use of trait scaling to understand sex‐defined economic strategies. [ABSTRACT FROM AUTHOR]

In addition to the performance of the respiratory system, COVID-19 can also have different degrees of abnormal liver function, and even liver injury and liver failure may occur in serious cases. In addition, infection with novel coronavirus will aggravate the liver damage of patients with chronic liver disease, resulting in a significant increase in severe morbidity and mortality. Based on this, this paper briefly reviews the mechanism of liver injury caused by COVID-19 and its impact on patients with chronic liver disease, in order to provide a theoretical basis for the prevention and treatment of COVID-19. [ABSTRACT FROM AUTHOR]

Understanding variation of carbon (C), nitrogen (N) and phosphorus (P) stoichiometry in common plant species across islands along a latitude gradient is insightful to reveal the adaptation strategies of plant species to environmental changes. Five common herbaceous species including Artemisia argyi, Setaira viridis, Humulus japonicus, Ophiopog onjaponicus, and Oxalis corniculata were sampled in 125 plots across nine islands in Eastern China. C, N and P contents in leaves, stems, and roots of five plant species were measured, and their relationships with soil C, N and P contents as well as mean annual air temperature (MAT) and mean annual precipitation (MAP) were investigated. The results showed that the range of C, N and P contents in aboveground parts of five species across nine islands was 352.16-518.16, 10.81-34.43, 0.58-2.38 mg⋅g-1, while the range of C:N, N:P and C:P was 11.98-38.99, 4.67-27.47, 133.39-748.54, respectively. In terms of roots, the range of C, N and P contents of five species was 312.28-493.34, 9.26-23.27, 0.40-2.10 mg⋅g-1, while the range of C:N, N:P and C:P was 18.18-46.79, 8.53-37.38, 174.45-1120.40, respectively. With the increases of latitude, contents of N and P in aboveground parts increased, but N:P decreased. Relative to N content, P content showed higher variation and was largely dependent on environment. Climate factors explained 60% of the variation of N and P contents and N:P across nine islands. In contrast, N and P contents and N:P of roots were independent of latitude, with climatic factors only explained 6%-10% of their variations. The contribution of climatic factors and soil nutrients contributed to the variations of N and P contents differed between above ground parts and roots of five species. Soil N and P had significant effects on P content in roots. Soil P content was positively correlated to aboveground P content. Soil properties explained 37% of the variation in N and P contents of plant roots. Our results suggested that latitude associated environment shifts were the main drivers of variation in N and P contents and N:P in aboveground parts, and soil nutrients especially affected variation in P in roots of five common plant species, when the effects of plant phylogeny was controlled. [ABSTRACT FROM AUTHOR]

Island vegetation plays an important role in biodiversity research across the world. The study of plant diversity in island is helpful for understanding the mechanism of plant diversity maintenance under land-sea interaction. Here, four typical plant communities (Quercus acutissima community, Robinia pseudoacacia community, Pinus thunbergii community and Vitex negundo community) in Miao Archipelago were selected to examine the species, functional and structural diversities and their responses to environmental factors at the community scale by using species diversity indices, functional diversity indices, as well as structural diversity indices. The results showed that the species richness and Rao index of P. thunbergii community was higher than that of Q. acutissima community and R. pseudoacacia community, but the structural diversity was lower. The species diversity and structural diversity of V. Negundo shrub were lower than that of forest community, but the functional diversity was higher than some forest communities. The relationship between the diversity of typical plant communities in island area illustrated a significant positive correlation between species richness with Rao index and tree height diversity, however the correlation with functional evenness was significantly negative. The structural diversity and functional evenness were determined by slope with negative and positive relationships, respectively. Functional heterogeneity, functional divergence and species diversity were affected largely by soil physical and chemical properties, displaying the positive relationship with soil bulk density and soil total carbon content, and a negative relationship with soil water content. In conclusion, diversity pattern of plant community in Miao Archipelago reflected not only the characteristics in mainland vegetation but also the special nature of the sea island. [ABSTRACT FROM AUTHOR]

In this study, two cationic lipids, each containing an α-tocopherol moiety and a biocompatible amino acid headgroup (histidine or lysine) linked through a biodegradable disulfide and carbamate bond, were prepared and evaluated in cell culture as nonviral gene delivery vectors. The physicochemical properties of these lipids, including size, zeta potential and cellular uptake of the lipoplexes formed with DNA, as well as the transfection efficacy (TE), were investigated. The results show that the chemical structure of the cationic headgroup affects the physicochemical parameters of these amino acid based lipids and especially the TE. In addition to their low cytotoxicity, these lipoplexes also showed comparable TE with the commercially available Lipofectamine 2000. The TE of the cationic lipid based on histidine was especially high, and was 4.3 times higher than that of a branched polyethylenimine in the presence of 10 % serum. These results demonstrate the promise of amino acid based lipids for safe and efficient gene delivery. [ABSTRACT FROM AUTHOR]

Despite its monotonous structure, sea-island plays a crucial role in sustaining biodiversity and ecosystem functioning. The objectives of this study were to explore the altitudinal variation of soil carbon (C), nitrogen (N), and phosphorus (P) pools in forests across 14 islands spanning temperate zone (TZ), northern subtropical zone (NSZ), mid-subtropical zone (MSZ), and sou-thern subtropical zone (SSZ) in eastern China. The relationships of soil C and nutrient pools with climatic factors and plant species diversity were examined across islands. Our results showed that soil C, N and P pools differed significantly across climatic zones. Soil C and N pools were the lowest in TZ (49.35 and 1.08 t·hm -2 ) and the highest in NSZ (137.25 and 4.63 t·hm -2 ). Soil P pool was the lowest in SSZ (1.3 t·hm -2 ) and the highest in NSZ (5.19 t·hm -2 ). There were significant difference in soil C, N and P pools among vegetation types. Soil C, N and P pools in deciduous forests were significantly higher in subtropical than in temperate islands. Soil C and N pools in evergreen broadleaved forests did not differ among sub-climatic zones, and soil P pool was lower in SSZ than that in NSZ and MSZ. The interactions across mean annual temperature, mean annual precipitation, soil water content, and plant species diversity positively affected latitudinal variation in soil C, N, and P pools. Plant species diversity positively associated with soil N pool, but negatively linked with soil P pool. In conclusion, the latitudinal trend of soil C pool is different, but that of soil N and P pools are identical between sea-island and mainland. The main abiotic and biotic dri-vers of soil C, N and P pools are water availability, temperature and plant species diversity across sea-islands in eastern China.

Island vegetation plays an important role in biodiversity research across the world. The study of plant diversity in island is helpful for understanding the mechanism of plant diversity maintenance under land-sea interaction. Here, four typical plant communities (Quercus acutissima community, Robinia pseudoacacia community, Pinus thunbergii community and Vitex negundo community) in Miao Archipelago were selected to examine the species, functional and structural diversities and their responses to environmental factors at the community scale by using species diversity indices, functional diversity indices, as well as structural diversity indices. The results showed that the species richness and Rao index of P. thunbergii community was higher than that of Q. acutissima community and R. pseudoacacia community, but the structural diversity was lower. The species diversity and structural diversity of V. Negundo shrub were lower than that of forest community, but the functional diversity was higher than some forest communities. The relationship between the diversity of typical plant communities in island area illustrated a significant positive correlation between species richness with Rao index and tree height diversity, however the correlation with functional evenness was significantly negative. The structural diversity and functional evenness were determined by slope with negative and positive relationships, respectively. Functional heterogeneity, functional divergence and species diversity were affected largely by soil physical and chemical properties, displaying the positive relationship with soil bulk density and soil total carbon content, and a negative relationship with soil water content. In conclusion, diversity pattern of plant community in Miao Archipelago reflected not only the characteristics in mainland vegetation but also the special nature of the sea island.

Understanding variation of carbon (C), nitrogen (N) and phosphorus (P) stoichiometry in common plant species across islands along a latitude gradient is insightful to reveal the adaptation strategies of plant species to environmental changes. Five common herbaceous species including Artemisia argyi, Setaira viridis, Humulus japonicus, Ophiopog onjaponicus, and Oxalis corniculata were sampled in 125 plots across nine islands in Eastern China. C, N and P contents in leaves, stems, and roots of five plant species were measured, and their relationships with soil C, N and P contents as well as mean annual air temperature (MAT) and mean annual precipitation (MAP) were investigated. The results showed that the range of C, N and P contents in aboveground parts of five species across nine islands was 352.16-518.16, 10.81-34.43, 0.58-2.38 mg·g -1 , while the range of C:N, N:P and C:P was 11.98-38.99, 4.67-27.47, 133.39-748.54, respectively. In terms of roots, the range of C, N and P contents of five species was 312.28-493.34, 9.26-23.27, 0.40-2.10 mg·g -1 , while the range of C:N, N:P and C:P was 18.18-46.79, 8.53-37.38, 174.45-1120.40, respectively. With the increases of latitude, contents of N and P in aboveground parts increased, but N:P decreased. Relative to N content, P content showed higher variation and was largely dependent on environment. Climate factors explained 60% of the variation of N and P contents and N:P across nine islands. In contrast, N and P contents and N:P of roots were independent of latitude, with climatic factors only explained 6%-10% of their variations. The contribution of climatic factors and soil nutrients contributed to the variations of N and P contents differed between above ground parts and roots of five species. Soil N and P had significant effects on P content in roots. Soil P content was positively correlated to aboveground P content. Soil properties explained 37% of the variation in N and P contents of plant roots. Our results suggested that latitude-associated environment shifts were the main drivers of variation in N and P contents and N:P in aboveground parts, and soil nutrients especially affected variation in P in roots of five common plant species, when the effects of plant phylogeny was controlled.