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Maize is a globally valuable commodity and one of the most extensively studied genetic model organisms. However, we know surprisingly little about the extent and potential utility of the genetic variation found in wild relatives of maize. Here, we characterize a high-density genomic variation map from 744 genomes encompassing maize and all wild taxa of the genus Zea, identifying over 70 million single-nucleotide polymorphisms. The variation map reveals evidence of selection within taxa displaying novel adaptations. We focus on adaptive alleles in highland teosinte and temperate maize, highlighting the key role of flowering-time-related pathways in their adaptation. To show the utility of variants in these data, we generate mutant alleles for two flowering-time candidate genes. This work provides an extensive sampling of the genetic diversity of Zea, resolving questions on evolution and identifying adaptive variants for direct use in modern breeding.

Aurantiadioic acids A (1) and B (2), two new furan-containing polyketides, and aurantoic acid A (3), a new natural product, were isolated from the liquid fermentation of the sika deer dung-derived actinomycete Actinocorallia aurantiaca. The structures of the new compounds were established by extensive spectroscopic methods, including 1D & 2D NMR, HRESIMS spectroscopic analysis. The absolute configuration of 3was assigned by comparison of the specific optical rotations with the reported derivatives. Biological activity evaluations suggested that compounds 1–3showed weak inhibition on NO production in the murine monocytic RAW 264.7 macrophages with IC50values of 35.8, 41.8, 45.2 μM, respectively. Compound 3showed weak inhibition on influenza A virus (A/PuertoRico/8/1934, H1N1) with an EC50value of 35.9 μM, and a selective index higher than 13.3.

Six new fusicoccane-type diterpenoids (2–7) were isolated from the fermentation broth of Streptomyces violascens, which was isolated from Ailuropoda melanoleuca(giant panda) feces. The structures of these new compounds were elucidated by a detailed spectroscopic data and X-ray crystallographic analysis. Compounds 5–7demonstrated cytotoxicity against five human cancer cell lines, with IC50values ranging from 3.5 ± 0.7 to 14.1 ± 0.8 μM. Cell adhesion, migration, and invasion assays showed that 6inhibited the migration and invasion of human hepatocellular carcinoma SMMC7721 cells in a dose-dependent manner. Through further investigation, it was revealed that 6inhibited the enzymatic activity of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), in addition to down-regulating the expressions of MMP-2 and MMP-9 at both the protein and mRNA levels to influence the migration and invasion of cancer cells.

Background: Maize (Zea maysL.) is at the vanguard facing the upcoming breeding challenges. However, both a super pan-genome for the Zeagenus and a comprehensive genetic variation map for maize breeding are still lacking. Results: Here, we construct an approximately 6.71-Gb pan-Zeagenome that contains around 4.57-Gb non-B73 reference sequences from fragmented de novo assemblies of 721 pan-Zeaindividuals. We annotate a total of 58,944 pan-Zeagenes and find around 44.34% of them are dispensable in the pan-Zeapopulation. Moreover, 255,821 common structural variations are identified and genotyped in a maize association mapping panel. Further analyses reveal gene presence/absence variants and their potential roles during domestication of maize. Combining genetic analyses with multi-omics data, we demonstrate how structural variants are associated with complex agronomic traits. Conclusions: Our results highlight the underexplored role of the pan-Zeagenome and structural variations to further understand domestication of maize and explore their potential utilization in crop improvement.

From a fermentation broth of Streptomyces albolongusobtained from Elephas maximusfeces, nine bafilomycins (1–9) and seven odoriferous sesquiterpenoids (10–16) were isolated. The structures of the new compounds, including three bafilomycins, 19-methoxybafilomycin C1 amide (1), 21-deoxybafilomycin A1 (2), and 21-deoxybafilomycin A2 (3), and two sesquiterpenoid degradation products, (1β,4β,4aβ,8aα)-4,8a-dimethyloctahydronaphthalene-1,4a(2H)-diol (10) and (1β,4β,4aβ,7α,8aα)-4,8a-dimethyloctahydronaphthalene-1,4a,7(2H)-triol (11), were elucidated by comprehensive spectroscopic data analysis. The cytotoxicity activity against four human cancer cell lines and antimicrobial activities against a panel of bacteria and fungi of all compounds isolated were evaluated. Compounds 1, 7, and 8were cytotoxic, with IC50values ranging from 0.54 to 5.02 μM. Compounds 2, 7, 8, and 10showed strong antifungal activity against Candida parapsilosis, with MIC values of 3.13, 1.56, 1.56, and 3.13 μg/mL respectively.

Endowing a chatbot with the capability of specific emotion expression will significantly improve both chatbot’s usability and users’ satisfaction. Recently, many studies on open-domain neural emotional, conversational models (chatbots) have been conducted. However, enabling a chatbot to control what kind of emotion to respond to in conversation explicitly is still under exploration. This paper proposes a novel affective chatbot based on the sequence-to-sequence framework, responding with appropriate emotion like a human. In particular, a new module called single emotion generator is designed in the new chatbot model to address the existing issue of controlling over reacting emotion. It enables the chatbot to select the appropriate emotion for a response when interacting with users. In the decoder, an affective lexicon-based method generates emotion-awareness responses based on the specific emotion controlled by the single emotion generator. The proposed chatbot outperforms mainstream baseline algorithms for both semantic fluency and emotion consistence metrics through experimental evaluation. The experimental results also demonstrate that the new chatbot obtains the ability to control the emotion for response explicitly and responds emotionally with the specific emotion.

Seven new 3,4,6-trisubstituted α-pyrone derivatives, violapyrones A–G (1–7), were isolated from Streptomyces violascensobtained from Hylobates hoolockfeces. Their structures were elucidated on the basis of detailed spectroscopic analysis. The antimicrobial activities of 1–7were evaluated against Gram-positive and Gram-negative bacteria and against fungi. Compounds 1–3showed moderate antibacterial activities against Bacillus subtilisand Staphylococcus aureuswith MIC values of 4–32 μg/mL.

Abstract: For the purpose of investigating the turbulent and spatial coherent characteristics of strong wind during typhoon landing period, two 3-dimensional ultrasonic anemometer stations were set up 30 m horizontally apart on the Macao Friendship Bridge to caputure the turbulent wind velocities of Typhoon Nuri. Based on the reliable and representative field measured data, the mean wind speed and direction, turbulence intensity, turbulence integral scale, turbulence power spectra, spatial correlation coefficient and coherence function were statistically evaluated. The field measurement analysis have presented the following results: 1) Two anemometer stations provided consistent results. The mean wind speed variation in time domain presented typical M-shape curves. The strong wind (10-minute mean wind speed higher than 8th grade in Beaufort wind scale) direction changed in a big range up to 122-degrees-angle, indicating the field measurements scoped over the typhoon landing period. 2) The ratio of the longitudinal, lateral and vertical turbulence intensities of the strong wind in the typhoon eye wall region was 1:0.96:0.36. Compared with the code defined ratio 1:0.88:0.5, the lateral component was larger and the vertical component was smaller. 3) The value of integral scale increased when the eye wall of Typhoon Nuri passed over the field measurement site. Before the center of Typhoon Nuri arrived, the integral scale of the strong typhoon wind was about twice compared with that for the non-typhoon wind. 4) The spatial correlation of the turbulent wind, coherence function curve and the decay factor had significant differences at different times during the typhoon process. In the eye wall of the typhoon, the horizontal spatial correlation was relatively strong and horizontally spatial correlation spectrum decayed slower with frequency increase. The minimum regressed coefficient C in coherence function model was 4.67, which is lower than the code defined low limit. The maximum decay factor was 27.75 which is larger than the code defined upper bound. The strong wind characteristic parameters of Typhoon Nuri mentioned above partly represented the turbulent and spatial coherent characteristic during strong typhoon wind period.

ABSTRACTThe giant panda evolved from omnivorous bears. It lives on a bamboo-dominated diet at present, but it still retains a typical carnivorous digestive system and is genetically deficient in cellulose-digesting enzymes. To find out whether this endangered mammalian species, like other herbivores, has successfully developed a gut microbiota adapted to its fiber-rich diet, we conducted a 16S rRNA gene-based large-scale structural profiling of the giant panda fecal microbiota. Forty-five captive individuals were sampled in spring, summer, and late autumn within 1 year. Significant intraindividual variations in the diversity and structure of gut microbiota across seasons were observed in this population, which were even greater than the variations between individuals. Compared with published data sets involving 124 gut microbiota profiles from 54 mammalian species, these giant pandas, together with 9 captive and 7 wild individuals investigated previously, showed extremely low gut microbiota diversity and an overall structure that diverged from those of nonpanda herbivores but converged with those of carnivorous and omnivorous bears. The giant panda did not harbor putative cellulose-degrading phylotypes such as Ruminococcaceaeand Bacteroidesbacteria that are typically enriched in other herbivores, but instead, its microbiota was dominated by Escherichia/Shigellaand Streptococcusbacteria. Members of the class Clostridiawere common and abundant in the giant panda gut microbiota, but most of the members present were absent in other herbivores and were not phylogenetically related with known cellulolytic lineages. Therefore, the giant panda appears not to have evolved a gut microbiota compatible with its newly adopted diet, which may adversely influence the coevolutionary fitness of this herbivore.IMPORTANCEThe giant panda, an endangered mammalian species endemic to western China, is well known for its unique bamboo diet. Unlike other herbivores that have successfully evolved anatomically specialized digestive systems to efficiently deconstruct fibrous plant matter, the giant panda still retains a gastrointestinal tract typical of carnivores. We characterized the fecal bacterial communities from a giant panda population to determine whether this animal relies on its symbiotic gut microbiota to cope with the complex carbohydrates that dominate its diet, as is common in other herbivores. We found that the giant panda gut microbiota is low in diversity and highly variable across seasons. It also shows an overall composition typical of bears and entirely differentiated from other herbivores, with low levels of putative cellulose-digesting bacteria. The gut microbiota of this herbivore, therefore, may not have well adapted to its highly fibrous diet, suggesting a potential link with its poor digestive efficiency.