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Dimorphic flowers growing on a single individual plant play a critical role in extreme adaption and reproductive assurance in plants and have high ecological and evolutionary significance. However, the omics bases underlying such a differentiation and maintenance remain largely unknown. We aimed to investigate this through genomic, transcriptome and metabolomic analyses of dimorphic flowers in an alpine biennial, Sinoswertia tetraptera (Gentianaceae). A high‐quality chromosome‐level genome sequence (903 Mb) was first assembled for S. tetraptera with 31,359 protein‐coding genes annotated. Two rounds of recent independent whole‐genome duplication (WGD) were revealed. Numerous genes from the recent species‐specific WGD were found to be differentially expressed in the two types of flowers, and this may have helped contribute to the origin of this innovative trait. The genes with contrasting expressions between flowers were related to biosynthesis of hormones, floral pigments (carotenoids and flavonoids) and iridoid compounds, which are involved in both flower development and colour. Metabolomic analyses similarly suggested differential concentrations of these chemicals in the two types of flowers. The expression interactions between multiple genes may together lead to contrasting morphology and chemical concentration and open versus closed pollination of the dimorphic flowers in this species for reproductive assurance. [ABSTRACT FROM AUTHOR]

This paper studies integral input-to-state stability (iISS) of a class of hybrid delayed systems with impulse and switching behavior, in which the delay-dependent impulse and switching behavior are allowed for asynchronous occurrence. Relative to admissible edge-dependent average dwell time (AED-ADT) concept of the switching signal, a fresh concept of admissible edge-dependent average impulsive interval (AED-AII) is proposed for the impulse signal. Several sufficient criteria for iISS are achieved by using multiple Lyapunov–Krasovskii functional (MLKF) tool, AED-ADT switching, and AED-AII schemes. An improved inequality that describing the relation among Lyapunov function continuous switching signal and discrete impulse is constructed, where the jump amplitude at discrete switching points and impulsive moments including delay-dependent part and delay-independent part are involved. Compared with existing results, our conclusions have the following novelties: (1) the influence of time delay existing in continuous dynamics and discrete impulse on the function part of L-K functional is dug out, which is less conservative; (2) the AED-AII scheme proposed in this paper is combined with the AED-ADT switching method, which contains a larger set of the impulsive and switching signal. Moreover, the stability criterion is suitable for the arbitrary time delay in situation that all the subsystems are destabilizing. Finally, an example is given to verify the validity of the results. [ABSTRACT FROM AUTHOR]

Objective: A sensitive and rapid ultra‐high‐performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method was successfully applied to the determination of 10 alkaloids in beagle dog plasma following a single oral dose of Xiatianwu capsules and enteric‐coated capsules, with theophylline serving as the internal standard (IS). Methods: Plasma samples were preprocessed using liquid–liquid extraction (LLE) with ethyl acetate ahead to separation using a gradient elution procedure on a Waters ACQUITY UPLC HSS T3 column (1.8 μm, 100 × 2.1 mm). The mobile phase was composed of 0.1% formic acid solution and acetonitrile at the flow rate of 0.3 ml/min. Multiple reaction monitoring (MRM) was used to determine the analytes in the positive ion mode. Results: The calibration curves for 10 analytes demonstrated a high degree of linearity (r ≥ 0.9920). The lower limit of quantification (LLOQ) values for 10 alkaloids were all more than 1.074 ng/ml, and matrix effects varied from 94.25% to 106.15%. The mean extraction recovery of quality control samples at low (LQC), medium (MQC) and high (HQC) concentrations, as well as IS, was all more than 76.60%. The intra‐day and inter‐day precision (RSD) also satisfied the requirement. Simultaneously, the variation of assay accuracies (RE) was between 13.05% and 9.38%. Conclusion: The test was validated in accordance with regulatory bioanalytical guidelines and was found to be suitable for use in a pharmacokinetic investigation of these compounds in beagle dogs after oral administration of Xiatianwu general capsules and enteric‐coated capsules. The Cmax of 10 alkaloids ranged from 52.61 to 192.46 ng/ml after oral administration of Xiatianwu capsules, and from 67.50 to 247.36 ng/ml. The Tmax was between 0.59 and 1.33 h of Xiatianwu capsules, and between 1.08 and 2.00 h of enteric‐coated capsules. The t1/2 ranged from 3.18 to 7.47 h of general capsules, and from 6.01 to 11.36 h. AUC0‐t ranged from 181.06 to 722.74 ng·h/ml of Xiatianwu capsules, and from 275.03 to 884.17 ng·h/ml of enteric‐coated capsules. The Cmax of enteric‐coated capsules were significantly increased except for tetrahydropalmatine and berberine. Tmax of general capsules were less than 1 h, and of enteric‐coated capsules were less than 2 h. The t1/2 of dehydrocorydaline, palmatine, tetrahydrojatrorrhizine, jatrorrhizine and coptisine in enteric‐coated capsules was longer than that in ordinary capsule. The AUC0‐t and AUC0‐∞ of bicuculline, dehydrocorydaline, protopine, magnoflorine, tetrahydrojatrorrhizine, jatrorrhizine, berberine and coptisine were all significantly higher in enteric‐coated capsules. [ABSTRACT FROM AUTHOR]

Medicago ruthenica has been recently cultivated as a new forage crop and has been recognized as a source of genes to improve abiotic stress tolerance in cultivated alfalfa because of its remarkable tolerance to drought, salinity‐alkalinity, and cold and snowy winters. Here, we reveal a chromosome‐scale genome sequence of M. ruthenica based on Illumina, PacBio, and Hi‐C data. The assembled genome consists of 903.56 Mb with 50,268 annotated protein‐coding genes, which is larger and contains relatively more genes than Medicago truncatula (420 Mb and 44,623 genes) and Medicago sativa spp. caerulea (793 Mb and 47,202 genes). All three species shared the ancestral Papilionoideae whole‐genome duplication event before their divergence. The more recent expansion of repetitive elements compared to that in the other two species was determined to have contributed greatly to the larger genome size of M. ruthenica. We further found that multiple gene and transcription factor families (e.g., SOS homologous genes, NAC, C2H2, and CAMTA) have expanded in M. ruthenica, which might have led to its enhanced tolerance to abiotic stress. In addition, M. ruthenica harbors more genes involved in the lignin and cellulose biosynthesis pathways than the other two species. Finally, population genomic analyses revealed two genetic lineages, reflecting the west and east of its geographical distribution, respectively. The two lineages probably diverged during the last glaciation and survived in multiple refugia at the last glacial maximum, followed by recent expansion. Our genomic data provide a genetic basis for further molecular breeding research on M. ruthenica and alfalfa. [ABSTRACT FROM AUTHOR]