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For the family of quadratic rational functions having a 2-cycle of bounded type Siegel disks, we prove that each of the boundaries of these Siegel disks contains at most one critical point. In the parameter plane, we prove that the locus for which the boundaries of the 2-cycle of Siegel disks contain two critical points is a Jordan curve. [ABSTRACT FROM AUTHOR]

As the core food crop of a bioregenerative life support system (BLSS), wheat is susceptible to pathogen infection due to the lack of effective microbial communities in the confined and isolated environment. Therefore, a thorough understanding of the dynamic changes in wheat rhizosphere fungi is of great significance for improving wheat production and ensuring the stability of the BLSS. In the current study, we collected samples of rhizosphere fungi in the four growth stages of wheat grown in the "Lunar Palace 365" experiment. We employed bioinformatics methods to analyze the samples' species composition characteristics, community network characteristics, and FUNGuild function analysis. We found that the species composition of rhizosphere fungi in the wheat at the tillering stage changed greatly in the closed and isolated environment, while the species composition in the seedling, flowering, and mature stage were relatively stable. The results of the FUNGuild function analysis showed that the functions of rhizosphere fungi changed during wheat development. The rhizosphere fungal community was centered on Ascomycota, Mortierellomycota, and Chytridiomycota, and the community showed the characteristics of a "small world" arrangement. The stage of wheat seedlings is characterized by a greater abundance, diversity, and complexity of the network of interactions in the rhizosphere mycorrhiza community, while the tillering stage exhibited a greater clustering coefficient. Based on the changes in species composition, guild function regulation, and community structure differences of the wheat rhizosphere fungi in the BLSS, our study identified the critical fungal species during wheat development, providing a reference for ensuring the health and yield of plants in the BLSS system. Key points: • The diversity, composition, FUNguild, and network structure of rhizosphere fungi were analyzed. • Ascomycota, Mortierellomycota, and Chytridiomycota were the center of the rhizosphere fungal community network. • The effects of different wheat developmental stages on the community composition, function, and network structure of rhizosphere fungi were examined. [ABSTRACT FROM AUTHOR]

The general public spends one-third of its time under artificial lighting, which lacks bands beneficial to human health, and long-term exposure will have a negative impact on bone health. Here, we report the effects of long-term, low-dose ultraviolet (UV) supplementation to white light-emitting diode (LED) light exposure on intestinal microorganisms and bone metabolism, as well as the correlations between the two. Normal and ovariectomized rats were irradiated with LED white light with or without supplementation with UV. The effects of UV supplementation on the intestinal flora and the relationship between the intestinal flora and bone were investigated by measuring the intestinal flora, bone metabolism markers, and bone histomorphology. UV supplementation affected the bone density and bone mass by changing the relative content of Firmicutes, Saccharibacteria, and Proteobacteria; however, the intestinal flora were not the only factors affecting bone. Ultraviolet supplementation changed the composition and function of the gut flora in the bone loss model. By increasing the synthesis of short-chain fatty acids and affecting immunomodulatory, intestinal flora directly or indirectly regulate the activity of osteoclasts and thus mediate UV-mediated improvements in bone metabolism. Our work shows that UV supplementation affects bone density by influencing the intestinal flora, introducing a novel strategy to develop healthier artificial light sources and prevent bone loss. Key points: • We measured the bone metabolism markers and bone histomorphometry of rats. • The diversity, composition, and function of intestinal flora were analyzed. • The relationship between gut microbiota and host bone physiology was analyzed. [ABSTRACT FROM AUTHOR]

Wheat is the core food crop in bioregenerative life support systems (BLSSs). In confined isolation environments, wheat growth suffers from a lack of stable microbial communities and is susceptible to pathogenic infections due to the culture substrate's limitations. To overcome this limitation, the time series changes of wheat rhizosphere microorganisms in wheat production must be understood. In the present study, we examined the rhizosphere microbial samples from wheat at four different growth stages from plants collected from a BLSS plant cabin. We employed bioinformatics analysis strategies to analyze the characteristics of species composition, function prediction, and community network. The species composition of wheat rhizosphere microorganisms was relatively stable in the seedling, tillering, and flowering stages in confined isolation environments. However, we observed marked microbial changes at mature stages. The results of functional prediction analysis suggest that the rhizosphere microbial community function of "Energy metabolism" gradually decreased, and the function of "Transmembrane transport" gradually increased during wheat development. The construction of the rhizosphere microbial community is non-random, scale-free and has the characteristics of a small world. We found the tillering stage to be more complex than the other stages. Our study reveals the composition characteristics, functional changes, and community structure fluctuations of rhizosphere bacteria at different development stages of wheat in the isolated and controlled environment, providing a theoretical basis for the efficient production of BLSS plant systems. Key Points: • We collected wheat rhizosphere microorganisms at different stages in a confined isolation environment. • The diversity, composition, function, and network structure of rhizosphere bacteria were analyzed. • The effect of different wheat stages on the composition, function, and network structure of rhizosphere microorganisms was speculated. [ABSTRACT FROM AUTHOR]

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The intelligent simulation of Sports can match the actual game and is of great significance to the development of Sports. Sports is a system in which multiple agents work together. Compared with a single agent, the learning space of multiple agents increases sharply as the number of agents increases, so the learning difficulty increases. Therefore, based on machine learning technology, this study combines with the actual situation to build a Sports simulation system. Moreover, after establishing a more reasonable team defensive formation and strategy, the overall movement of the agent is optimized, and the corresponding structural model has been established in combination with various actions. In addition, this study designs a controlled trial to analyze the performance of the model. The research shows that the proposed method has certain effects and can provide theoretical reference for subsequent related research. [ABSTRACT FROM AUTHOR]

Wheat seedlings are significantly impacted by the presence of bacteria. However, bacteria are unavoidably growing together with wheat. The study aimed to reveal wheat photosynthesis, phyllosphere bacterial community composition, and a shift in the bacterial community following different density treatments in a closed artificial ecosystem. Here, we report the relationship between photosynthesis and bacterial community in wheat seedlings for different planting densities. In this closed artificial ecosystem, a total of 30 phyla were detected, with 17 of them were simultaneously present in four treatments, under high light intensity and carbon dioxide growth environment. The key phyla detected include Firmicutes, Proteobacteria, and Bacteroidetes. We found that planting densities significantly impacted the photosynthetic characteristics of wheat and bacterial genetic biodiversity, but not on species composition of the bacterial community. Network analysis shows that the phyllosphere bacteria network structures were characterized by the clustering coefficient and modularity. Network for the 1000 plants/m2 treatment group exhibits the highest levels of average clustering coefficient but lowest modularity and number of modules, among all plant densities tested. In addition, the network for the 1200 plants/m2 treatment group exhibits the best characteristics in terms of net photosynthesis rate and intrinsic water use efficiency, higher complex phyllosphere community network structures, higher abundance of Corynebacterium, and more function of "Amino acid metabolism", which encourages the plants to grow better. The findings presented in this work elucidated the role of plant density in the growth of phyllosphere bacteria during wheat seedlings and provided theoretical support for reasonable wheat density cultivation in closed artificial ecosystems and wheat field production. [ABSTRACT FROM AUTHOR]

The growth of plants under high carbon dioxide (CO2) concentrations (≥ 1000 ppm) is explored for the climate change and the bioregenerative life support system (BLSS) environment of long-duration space missions. Wheat (Triticum aestivum L.) is a grass cultivated for cereal grain—a global staple food including astronauts. Light and CO2 are both indispensable conditions for wheat seedlings. This study provides insights on the physiology, antioxidant capacity and photosynthetic characteristics of wheat seedlings under a range of photosynthetic photon flux densities in a closed system simulating BLSS with high CO2 concentration. We found that the Fv/Fm, Fv/F0, chlorophyll content, intrinsic water use efficiencies (WUEi), membrane stability index (MSI), and malondialdehyde (MDA) of wheat seedlings grown under an intermediate light intensity of 600 μmol m−2 s−1 environment were all largest. Interestingly, the high light intensity of 1200 mol m−2 s−1 treatment group exhibits the highest net photosynthetic rate but the lowest MDA content. The stomatal conductance and F0 of high light intensity of 1000 μmol m−2 s−1 treatment group were both significantly higher than that of other groups. Our study provides basic knowledge on the wheat growth in different environments, especially in a closed ecosystem with artificial lights. [ABSTRACT FROM AUTHOR]

We prove the existence of rational maps whose Julia sets are Sierpiński carpets having positive area. Such rational maps can be constructed such that they either contain a Cremer fixed point, a Siegel disk or are infinitely renormalizable. We also construct some Sierpiński carpet Julia sets with zero area but with Hausdorff dimension two. Moreover, for any given number s ∈ (1 , 2) , we prove the existence of Sierpiński carpet Julia sets having Hausdorff dimension exactly s. [ABSTRACT FROM AUTHOR]

Since the discovery of metal nanoparticles (NPs) in the 1960s, unknown toxicity, cost and the ethical hurdles of research in humans have hindered the translation of these NPs to clinical use. In this work, we demonstrate that Pt NPs with protein coronas are generated in vivo in human blood when a patient is treated with cisplatin. These self-assembled Pt NPs form rapidly, accumulate in tumors, and remain in the body for an extended period of time. Additionally, the Pt NPs are safe for use in humans and can act as anti-cancer agents to inhibit chemotherapy-resistant tumor growth by consuming intracellular glutathione and activating apoptosis. The tumor inhibitory activity is greatly amplified when the Pt NPs are loaded in vitro with the chemotherapeutic drug, daunorubicin, and the formulation is effective even in daunorubicin-resistant models. These in vivo-generated metal NPs represent a biocompatible drug delivery platform for chemotherapy resistant tumor treatment. Platinum based drugs like cisplatin are common chemotherapy treatments for cancer. Here, the authors report on the in situ formation of platinum nanoparticles in patients and demonstrated how platinum nanoparticles can be synthesized using patients' blood and provide effective drug delivery and cancer treatments. [ABSTRACT FROM AUTHOR]

The microbial communities of plant ecosystems are in relation to plant growing environment, but the alteration in biodiversity of rhizosphere and phyllosphere microbial communities in closed and controlled environments is unknown. The purpose of this study is to analyze the change regularity of microbial communities with wheat plants dependent-cultivated in a closed artificial ecosystem. The microbial community structures in closed-environment treatment plants were investigated by a culture-dependent approach, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), and Illumina Miseq high-throughput sequencing. The results indicated that the number of microbes decreased along with time, and the magnitude of bacteria, fungi, and actinomycetes were 10-10, 10, and 10-10 CFU/g (dry weight), respectively. The analysis of PCR-DGGE and Illumina Miseq revealed that the wheat leaf surface and near-root substrate had different microbial communities at different periods of wheat ecosystem development and showed that the relative highest diversity of microbial communities appeared at late and middle periods of the plant ecosystem, respectively. The results also indicated that the wheat leaf and substrate had different microbial community compositions, and the wheat substrate had higher richness of microbial community than the leaf. Flavobacterium, Pseudomonas, Paenibacillus, Enterobacter, Penicillium, Rhodotorula, Acremonium, and Alternaria were dominant in the wheat leaf samples, and Pedobacter, Flavobacterium, Halomonas, Marinobacter, Salinimicrobium, Lysobacter, Pseudomonas, Halobacillus, Xanthomonas, Acremonium, Monographella, and Penicillium were dominant populations in the wheat near-root substrate samples. [ABSTRACT FROM AUTHOR]

Global warming is partly due to the increase in atmospheric CO concentration. In the last two decades, many investigations have studied the effect of high CO levels on crops. However, nearly all studies have examined the effects of CO enrichment up to about 1200 μmol mol. In general, more CO is beneficial to plant growth because plants feed on CO. Here we tested the effect of CO levels from 400 to 5000 μmol mol on the yield and antioxidant capacity of Chinese cabbage, Brassica chinensis, and lettuce, Lactuca sativa. Total antioxidant capacity was measured using the ferric ion reducing antioxidant potential assay and the diphenyl-picryl-hydrazylhydrate free radical detection. Our results show that, as expected, CO concentrations of 1000-3000 μmol mol enhance the yields and contents of polyphenols, flavonoids and vitamin C in both vegetables. However, surprisingly, further increase up to 5000 μmol mol CO decreased yields and contents of polyphenols, flavonoids and vitamin C. Our findings thus show that very high atmospheric CO levels are impeding the growth of tested plants. They also suggest that agricultural food and production could be depleted at high atmospheric CO levels. [ABSTRACT FROM AUTHOR]

Although terrestrial CO concentrations [CO] are not expected to reach 1000 μmol mol (or ppm) for many decades, CO levels in closed systems such as growth chambers and greenhouses can easily exceed this concentration. CO levels in life support systems (LSS) in space can exceed 10,000 ppm (1 %). In order to understand how photosynthesis in C plants may respond to elevated CO, it is necessary to determine if leaves of closed artificial ecosystem grown plants have a fully developed C photosynthetic apparatus, and whether or not photosynthesis in these leaves is more responsive to elevated [CO] than leaves of C plants. To address this issue, we evaluated the response of gas exchange, water use efficiency, and photosynthetic efficiency of PSII by soybean ( Glycine max (L.) Merr., 'Heihe35') of a typical C plant and maize ( Zea mays L., 'Susheng') of C plant under four CO concentrations (500, 1000, 3000, and 5000 ppm), which were grown under controlled environmental conditions of Lunar Palace 1. The results showed that photosynthetic pigment by the C plants of soybean was more sensitive to elevated [CO] below 3000 ppm than the C plants of maize. Elevated [CO] to 1000 ppm induced a higher initial photosynthetic rate, while super-elevated [CO] appeared to negate such initial growth promotion for C plants. The C plant had the highest ETR, φPSII, and qP under 500-3000 ppm [CO], but then decreased substantially at 5000 ppm [CO] for both species. Therefore, photosynthetic down-regulation and a decrease in photosynthetic electron transport occurred by both species in response to super-elevated [CO] at 3000 and 5000 ppm. Accordingly, plants can be selected for and adapt to the efficient use of elevated CO concentration in LSS. [ABSTRACT FROM AUTHOR]

Silkworm ( Bombyx mori L.) larvae were used as an ideal animal protein source for astronauts in the bioregenerative life support system (BLSS). Here, we compared the difference in bacterial communities of the silkworm larval gut between the BLSS rearing way (BRW) and the traditional rearing way (TRW) through culture-dependent approach, 16S rRNA gene analysis, and denaturing gradient gel electrophoresis (DGGE). The culture-dependent approach revealed that the numbers of gut bacteria of silkworm in the BRW significantly decreased compared with that of the TRW. The analysis of clone libraries showed that the gut microbiota in the BRW was significantly less diverse than that in the TRW. Acinetobacter and Bacteroides were dominant populations in the BRW, and Bacillus and Arcobacter dominated in the TRW. DGGE profiles confirmed the difference of silkworm gut bacterial community between two rearing ways. These results demonstrate that gut bacteria change from the BRW contributes to the decrease of silkworm physiological activity. This study increases our understanding of the change of silkworm gut microbiota in response to lettuce leaf feeding in the BRW. We could use the dominant populations to make probiotic products for nutrient absorption and disease prevention in the BLSS to improve gut microecology, as well as the yield and quality of animal protein. [ABSTRACT FROM AUTHOR]