Flower color polymorphism of a wild Iris on the Qinghai-Tibet plateau.

BACKGROUND: Flower color plays a crucial role in attracting pollinators and facilitating environmental adaptation. Investigating the causes of flower color polymorphism and understanding their potential effects on both ecology and genetics can enhance our understanding of flower color polymorphism in wild plant. RESULTS: In this study, we examined the differences of potential male and female fitness between purple- and yellow- flower individuals in Iris potaninii on the Qinghai-Tibet Plateau, and screened key genes and positively selective genes involved in flower color change. Our results showed that yellow flower exhibited a higher pollen-to-ovule ratio. Yellow flowers were derived from purple flowers due to the loss of anthocyanins, and F3H could be an essential gene affecting flower color variation though expression regulation and sequence polymorphism in this species. Furthermore, our findings suggest that genes positively selected in yellow-flowered I. potaninii might be involved in nucleotide excision repair and plant-pathogen interactions. CONCLUSIONS: These results suggest that F3H induces the flower color variation of Iris potaninii, and the subsequent ecological and additive positive selection on yellow flowers may further enhance plant adaptations to alpine environments.

Multiple lines of evidence supports the two varieties of Halenia elliptica (Gentianaceae) as two species.

Delimiting species requires multiple sources of evidence. Here, we delimited two varieties of Halenia elliptica (Gentianaceae) using several lines of evidence, including morphological traits and mating system in a sympatric population, phylogenetic relationships based on nrITS and cpDNA (rpl16) data, and complete chloroplast genome sequences. Comparative analysis of 21 morphological traits clearly separates the two varieties of H. elliptica. Examination of the flowering process and pollination treatments indicate that H. elliptica var. grandiflora produces seeds via outcrossing, whereas H. elliptica var. elliptica produces seeds via mixed mating. Furthermore, hand-pollinated hybridization of the two varieties produced no seeds. Observations of pollinators showed that when bees began a pollination bout on H. elliptica var. grandiflora they preferred to continue pollinating this variety; however, when they began a pollination bout on H. elliptica var. elliptica, they showed no preference for either variety. Phylogenetic analysis confirmed the monophyly of H. elliptica, which was further divided into two monophyletic clades corresponding to the two varieties. A large number of variants from the chloroplast genomes reflected remarkable genetic dissimilarities between the two varieties of H. elliptica. We recommend that the two varieties of H. elliptica should be revised as two species (H. elliptica and H. grandiflora). Our findings indicate that H. elliptica varieties may have split into two separate species due to a shift in mating system, changes in flowering phenology and/or post-pollination reproductive isolation.

Development of Microsatellite Markers for a Dioecious Herpetospermum pedunculosum (Cucurbitaceae).

Understanding the evolution of flower diversity is a central topic in plant evolutionary ecology, and natural selection on floral traits via male fitness could be estimated quantitatively using microsatellites. Here, based on RNA sequencing, we developed simple sequence repeat primers and verified polymorphisms in 2 wild populations of Herpetospermum pedunculosum (Cucurbitaceae), a dioecious annual plants native to the Himalaya Mountains. A total of 131 paired primers were designed; 15 paired primers were found to be polymorphic, with the expected heterozygosity varying between 0.280 and 0.767. We also identified 58 genotypes in 20 plants from the 2 populations. Conclusively, these primers could be effective in examining male fitness and population genetic structure of H pedunculosum in future studies.

An anti-forensic scheme on computer graphic images and natural images using generative adversarial networks.

Computer graphic images (CGI) can be manufactured very similar to natural images (NI) by state-of-the-art algorithms in computer graphic filed. Thus, there are various identification algorithms proposed to detect CGI. However, the manipulation is complicated and difficult for an ultimate CGI against the forensic algorithms. Further, the forensics on CGI and NI made achievements in the different aspects with the encouragement of deep learning. Though the generated CGI can achieve high quality automatically by generative adversarial networks (GAN), CGI generation based on GAN is difficult to ensure that it cannot be detected by forensics. In this paper, we propose a brief and effective architecture based on GAN for preventing the generated images being detected under the forensics on CGI and NI. The adapted characteristics will make the CGI generated by GAN fools the detector and keep the end-to-end generation mode of GAN.

Cell number explains the intraspecific spur-length variation in an Aquilegia species.

Variations of nectar spur length allow pollinators to utilize resources in novel ways, leading to the different selective pressures on spurs and allowing taxa to diversify. However, the mechanisms underlying spur length variation remain unclear. Interspecific comparisons of spur length suggest that both cell division and anisotropic expansion could explain the changes of spur length, and that hormone-related genes contribute to the process of spur formation. In contrast, little is known about intraspecific spur length variation. In Aquilegia rockii, spur length varies strikingly, ranging from 1 mm to 18 mm. To examine the potential mechanisms underlying spur length variation in A. rockii, we observed cell morphology and analyzed RNA-seq of short- and long-spurred flowers. Scanning electron microscopy revealed that at two positions on spurs there were no differences in either cell density or cell anisotropy between short- and long-spurred flowers, suggesting that in A. rockii changes in cell number may explain variations in spur length. In addition, we screened transcriptomes of short- and long-spurred flowers for differentially expressed genes; this screen identified several genes linked to cell division (e.g., F-box, CDKB2-2, and LST8), a finding which is consistent with our analysis of the cellular morphology of spurs. However, we did not find any highly expressed genes involved in the hormone pathway in long-spurred flowers. In contrast to previous hypotheses that anisotropic cell expansion leads to interspecific spur variation in Aquilegia, our results suggest that cell number changes and related genes are mainly responsible for spur length variations of A. rockii. Furthermore, the underlying mechanisms of similar floral traits in morphology may be quite different, enriching our understanding of the mechanisms of flower diversity in angiosperms.

A mathematical optimization model for efficient assignment of inpatients in an oncology center in China.

This paper addresses a problem for assignment of chemo-receiving inpatients in an oncology care center, which has not been addressed in the literature. Chemotherapy is regarded as one of the most effective treatments for cancer. In recent years, as cancer incidence increased, the number of patients admitted to a cancer treatment center has also been rising. How to balance the workload of medical service resources by planning admission of patients has become an essential problem that must be given consideration by policy- makers. The allocation of chemotherapy patients, different from that of the routine inpatients, is restrained by treatment agreements of patients and presents periodic features. Therefore, the allocation of chemotherapy patients is much more difficult than that of routine patients. A mixed integer programming (MIP) model was first formulated for this problem in order to maximize the usage of beds. Specific features of chemotherapy, such as chemotherapy protocols, were integrated into this model. The inpatient assignment problem was proved to be non-deterministic polynomial- complete and we propose an exact method to solve it. Numerical experiments on suitable use-case scenarios and a practical Chinese oncology center were performed to test and evaluate this model. The obtained results demonstrated the effectiveness of our method. Some useful managerial implication are provided for policy-makers through the analysis of obtained results. The models and methods suggested here can be effectively applied in similar departments of other countries and regions.

Development and characterization of EST-SSR markers in Bombax ceiba (Malvaceae).

PREMISE OF THE STUDY: Bombax ceiba (Malvaceae), commonly known as silk cotton tree, is a multipurpose tree species of tropical forests. Novel expressed sequence tag-simple sequence repeat (EST-SSR) markers were developed and characterized for the species using transcriptome analysis. METHODS AND RESULTS: A total of 33 new EST-SSR markers were developed for B. ceiba, of which 13 showed polymorphisms across the 24 individuals from four distant populations tested in the study. The results showed that the number of alleles per polymorphic locus ranged from two to four, and the expected heterozygosity and observed heterozygosity per locus varied from 0.043 to 0.654 and from 0 to 0.609, respectively. CONCLUSIONS: These newly developed EST-SSR markers can be used in phylogeographic and population genetic studies to investigate the origin of B. ceiba populations. Furthermore, these EST-SSR markers could also greatly promote the development of molecular breeding studies pertaining to silk cotton tree.

Rothia endophytica sp. nov., an actinobacterium isolated from Dysophylla stellata (Lour.) Benth.

A novel endophytic actinobacterium, designated strain YIM 67072(T), was isolated from healthy roots of Dysophylla stellata (Lour.) Benth. Cells of this aerobic, cream-yellow-coloured strain occurred singly, in pairs or in tetrads, were Gram-stain-positive and ovoid- to spherical-shaped. Strain YIM 67072(T) grew at 4-45 °C, pH 5.0-10.0 and in the presence of 0-7 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 67072(T) belonged to the genus Rothia. The isolate contained MK-7 as the major component of the quinone system. The peptidoglycan type was A3α. The polar lipid profile consisted predominantly of diphosphatidylglycerol and glycolipids. The major fatty acids were anteiso-C15 : 0, iso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The DNA G+C content was 53.2 mol%. However, strain YIM 67072(T) differed from its closest relatives Rothia nasimurium CCUG 35957(T) (98.5 % 16S rRNA gene sequence similarity), Rothia amarae JCM 11375(T) (97.6 %) and Rothia terrae L-143(T) (97.3 %) in many phenotypic characteristics. Moreover, the levels of DNA-DNA relatedness between the novel isolate and the three above-mentioned type strains were 28.7±1.3 %, 36.5±1.2 %, 46.8±1.5 %, respectively. Based on comparative analysis of physiological and chemotaxonomic data, strain YIM 67072(T) represents a novel species of the genus Rothia, for which the name Rothia endophytica sp. nov. is proposed. The type strain is YIM 67072(T) ( = DSM 26247(T) = JCM 18541(T)).