3,274 research outputs found

    5,7-Dihydr­oxy-3,6,8-trimethoxy­flavone

    Get PDF
    The title compound (systematic name: 5,7-dihydr­oxy-3,6,8-trimeth­oxy-4H-chromen-4-one), C18H16O7, is a flavone that was isolated from Ainsliaea henryi. There are two mol­ecules in the asymmetric unit, one of which has a disordered meth­oxy group [occupancy ratio 0.681 (9):0.319 (9)]. Both mol­ecules have an intra­molecular O—H⋯O hydrogen bond. In the crystal, mol­ecules are linked into O—H⋯O hydrogen-bonded chains parallel to [110]

    A dimeric sesquiterpene, gochnatiolide A

    Get PDF
    The title compound [systematic name: 5′a-hydroxy-1′,3,6,8′-tetrakis(methylene)-3a,4,5,5′,5′a,6,6′,6a,7,7′,7′a,8′,9a,9b,10′a,10′b-hexadecahydrospiro[azuleno[4,5-b]furan-9(2H),3′-[3H]benz[1,8]azuleno[4,5-b]furan]-2,2′,8,9′(1′H,3H,4′H)-tetrone acetone 0.92-solvate], C30H30O7·0.92C3H6O, is a dimeric sequiterpene formed by a cyclohexane system connecting two monomeric sesquiterpene lactone units of dehydro­zaluzanin C. It was isolated from Ainsliaea henryi

    SLDR: a computational technique to identify novel genetic regulatory relationships

    Get PDF
    We developed a new computational technique called Step-Level Differential Response (SLDR) to identify genetic regulatory relationships. Our technique takes advantages of functional genomics data for the same species under different perturbation conditions, therefore complementary to current popular computational techniques. It can particularly identify "rare" activation/inhibition relationship events that can be difficult to find in experimental results. In SLDR, we model each candidate target gene as being controlled by N binary-state regulators that lead to ≤2N observable states ("step-levels") for the target. We applied SLDR to the study of the GEO microarray data set GSE25644, which consists of 158 different mutant S. cerevisiae gene expressional profiles. For each target gene t, we first clustered ordered samples into various clusters, each approximating an observable step-level of t to screen out the "de-centric" target. Then, we ordered each gene x as a candidate regulator and aligned t to x for the purpose of examining the step-level correlations between low expression set of x (Ro) and high expression set of x (Rh) from the regulator x to t, by finding max f(t, x): |Ro-Rh| over all candidate × in the genome for each t. We therefore obtained activation and inhibitions events from different combinations of Ro and Rh. Furthermore, we developed criteria for filtering out less-confident regulators, estimated the number of regulators for each target t, and evaluated identified top-ranking regulator-target relationship. Our results can be cross-validated with the Yeast Fitness database. SLDR is also computationally efficient with o(N²) complexity. In summary, we believe SLDR can be applied to the mining of functional genomics big data for future network biology and network medicine applications

    Will Your Project Get the Green Light? Predicting the Success of Crowdfunding Campaigns

    Get PDF
    Capital is always essential for a business project over times. After emerging in 2000, crowdfunding gradually becomes one of the most popular fundraising resources. However, the mechanism of crowdfunding significantly differs from traditional capital-collecting approaches. As long as the amount of pledged money reaches the goal in time, the project succeeds, its initiator receives the funds, the platform gains the revenue, and its backers acquire rewards. Reaching the goal by deadline becomes an important issue. The goal of our study is to develop an effective technique for predicting whether a crowdfunding campaign will succeed or fail. On the basis of a dataset collected from Kickstarter, our empirical evaluation results suggest that our proposed technique significantly outperforms the benchmark method. In addition, with the use of time-dependent factors, the prediction accuracy improves from 72.89% at day 0 to 87.13% at the first day and eventually to 89.62% at day 7

    Ball Pad Mold Electromagnetic Forming Process for Aluminium Alloy Sheet

    Get PDF
    In order to meet requirements of lightweight technology in the field of aerospace, the new forming technology for aluminium alloy skin parts and integral panel are brought to more attention. Based on the principle of electromagnetic forming (EMF) and energy distribution, a new electromagnetic forming process using ball as pad mold for aluminium alloy sheet forming was suggested and test apparatus was designed. The new method was verified by the finite element simulation and experimental technology, and all studies were carried out on 2024-T3 aluminium alloy sheet. The results show that the new process of ball pad mold electromagnetic forming is feasible to aluminium alloy sheet parts forming. Rubber cushion thickness and electromagnetic pulse voltage are significant contributors to the curvature radius of the test sample. Based on these observations, application advantages and prospects of this new process were pointed out, and the subsequent research was put forward

    Biological Evaluation of an Antibiotic DC-81–Indole Conjugate Agent in Human Melanoma Cell Lines

    Get PDF
    Pyrrolo[2, 1-c][1, 4]benzodiazepines (PBDs) are potent inhibitors of nucleic acid synthesis because of their ability to recognize and bind to specific sequences of DNA and form a labile covalent adduct. DC-81, an antitumor antibiotic produced by Streptomyces species, is a PBD. We combined DC-81 and an indole carboxylate moiety to synthesize a hybrid designed to have much higher sequence selectivity in DNA interactivity. In this paper, the cytotoxic potency of the hybrid in human melanoma cell lines was studied. XTT assay demonstrated that the DC-81-indole conjugate possessed cytotoxicity against human melanoma cell lines

    The emerging role of cellular senescence in renal diseases

    Get PDF
    Cellular senescence represents the state of irreversible cell cycle arrest during cell division. Cellular senescence not only plays a role in diverse biological events such as embryogenesis, tissue regeneration and repair, ageing and tumour occurrence prevention, but it is also involved in many cardiovascular, renal and liver diseases through the senescence-associated secretory phenotype (SASP). This review summarizes the molecular mechanisms underlying cellular senescence and its possible effects on a variety of renal diseases. We will also discuss the therapeutic approaches based on the regulation of senescent and SASP blockade, which is considered as a promising strategy for the management of renal diseases

    PARENTAGE OF OVERLAPPING OFFSPRING OF AN ARBOREAL-BREEDING FROG WITH NO NEST DEFENSE: IMPLICATIONS FOR NEST SITE SELECTION AND REPRODUCTIVE STRATEGY

    Get PDF
    Overlapping offspring occurs when eggs are laid in a nest containing offspring from earlier reproduction. To unveil the parentage between overlapping offspring and parents is critical in understanding oviposition site selection and the reproductive strategies of parents. Amplectant pairs of an arboreal-breeding frog, Kurixalus eiffingeri, lay eggs in tadpole-occupied nests where offspring of different life stages (embryos and tadpoles) coexist. We used five microsatellite DNA markers to assess the parentage between parents and overlapping offspring. Results showed varied parentage patterns, which may differ from the phenomenon of overlapping egg clutches reported earlier. Parentage analyses showed that only 58 and 25% of the tadpole-occupied stumps were reused by the same male and female respectively, partially confirming our prediction. Re-nesting by the same individual was more common in males than females, which is most likely related to the cost of tadpole feeding and/or feeding schemes of females. On the other hand, results of parentage analyses showed that about 42 and 75 % of male and female respectively bred in tadpole-occupied stumps where tadpoles were genetically unrelated. Results of a nest-choice experiment revealed that 40% of frogs chose tadpole-occupied bamboo cups when we presented identical stumps, without or with tadpoles, suggesting that the habitat saturation hypothesis does not fully explain why frogs used the tadpole-occupied stumps. Several possible benefits of overlapping offspring with different life stages were proposed. Our study highlights the importance of integrating molecular data with field observations to better understand the reproductive biology and nest site selection of anuran amphibians
    corecore