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Toonasinemines A–K ( 1 – 12 ), 12 new azadirone- and gedunin-type limonoids with eight-classes of modified furan rings, were isolated from the root barks of Toona sinensis (A. Juss.) Roem. Their structures were elucidated based on detailed spectroscopic analyses, and the absolute configurations of 1 – 9 were established by the electronic circular dichroism exciton chirality method. The lactam-bearing moieties in compounds 1 – 7 were rare in limonoids family. Results of bioactivities screening exhibited that 1 , 4 , and 8 showed moderate cytotoxicities against HepG2, MCF-7, and U2OS human cancer cell lines, and 1 , 2 , 6 , 8 , and 9 exhibited marked inhibitory effects on nitric oxide (NO) production in LPS-activated RAW 264.7 macrophages at nontoxic concentration. [ABSTRACT FROM AUTHOR]

In the recent worldwide campaign for the global biodiversity inventory via DNA barcoding, a simple and easily used measure of confidence for assigning sequences to species in DNA barcoding has not been established so far, although the likelihood ratio test and the Bayesian approach had been proposed to address this issue from a statistical point of view. The TDR (Two Dimensional non-parametric Resampling) measure newly proposed in this study offers users a simple and easy approach to evaluate the confidence of species membership in DNA barcoding projects. We assessed the validity and robustness of the TDR approach using datasets simulated under coalescent models, and an empirical dataset, and found that TDR measure is very robust in assessing species membership of DNA barcoding. In contrast to the likelihood ratio test and Bayesian approach, the TDR method stands out due to simplicity in both concepts and calculations, with little in the way of restrictive population genetic assumptions. To implement this approach we have developed a computer program package (TDR1.0beta) freely available from ftp://202.204.209.200/education/video/TDR1.0beta.rar. [ABSTRACT FROM AUTHOR]

The plants of genus Toona are well known for diverse limonoid secondary metabolites, while polyacetylenes are rarely found from Toona species. In this work, six new polyacetylenes toonasindiynes A-F (1 – 6) and six known analogues (7 – 12) were isolated from the root bark of Toona sinensis. Their structures and absolute configurations were elucidated by HRESIMS, 1D and 2D NMR spectroscopic analysis, modified Mosher's method, and biosynthetic consideration. These polyacetylenes share the same 4,6-diyne moiety with different side chain length and different oxidation degree. Bioactivity screening revealed the cytotoxic activity of 3 , 5 , 9 , and 11 against U2OS cells, and the inhibitory effects on nitric oxide (NO) production of 1 , 2 , 5 , 8 , 9 , and 11 in lipopolysaccharide-induced RAW 264.7 cells. Unlabelled Image • Six new polyacetylenes were isolated from the edible plant Toona sinensis. • Absolute configurations were determined by modified Mosher's method. • Some polyacetylenes showed potent cytotoxic and anti-inflammatory activities. [ABSTRACT FROM AUTHOR]

Nine new euphane- and apotirucallane-type triterpenoids (Toosendines A–I; 1–9 ), along with three known tirucallane-type compounds were isolated from the barks of Melia toosendan . Their structures were elucidated based on detailed spectroscopic analyses (HRESIMS, 1D/2D-NMR) and circular dichroism spectra. Results of bioactivities screening exhibited that compounds 1 , 4 and 5 showed remarkable NO inhibitory activities in LPS-activated RAW 264.7 macrophages, meanwhile, compounds 1 and 4 showed moderate cytotoxicities against U2OS human cancer cell line. [ABSTRACT FROM AUTHOR]

Highlight: [•] MiR-21 plays a significant role in 5-FU resistance. [•] This role might be attributed to targeting of hMSH2 as well as TP and DPD via miR-21 targeted hMSH2. [•] Indirectly targeted TP and DPD to influence 5-FU chemotherapy sensitivity. [ABSTRACT FROM AUTHOR]

The dynamic compaction (DC) method is a versatile ground treatment technique with growing popularity. It is applicable to a wide variety of soil types and conditions, particularly sandy materials and granular fills. This study presents a case history of the dynamic compaction with a high energy level of 6,000 kN·m on granular deposits at a site in China. The reclaimed site featured loose backfill with heterogeneity and saturated silt. In order to properly deal with such soil conditions and to optimize the DC design, field tests were conducted to determine the influencing factors in DC. Deformation tests were performed to ascertain the rational spacing of impacts and the optimal number of drops and to provide proofs to the adjustment of the original DC procedure. Monitoring of the pore water pressure helped obtain the time delay between passes. The approach to assess the depth of improvement was discussed based on interpretations of the spectral analysis of surface waves (SASW) test. Analysis of the SASW and plate-load tests demonstrated significant improvement in the soils at the site, with no obvious weak layers. Following dynamic compaction, the allowable ground-bearing capacity and the depth of improvement at the site were no less than 270 kPa and 7.4 m, respectively. [ABSTRACT FROM AUTHOR]

Abstract  The paper reports a study into the dynamic compaction of very coarse grained material placed over soft clays in a coastal reclamation area. It was found that higher energy levels are more effective than low impact energy levels, which can result in ground heave between impact points. Spectral analysis of surface wave (SASW) tests and plate load tests confirmed the effect of the dynamic compaction extended to at least 10 m, with no obvious weak layers identified. Following dynamic compaction, the allowable bearing capacity was >120 kPa. [ABSTRACT FROM AUTHOR]

The optical microcavity effect of the homo-tandem solar cells is explored utilizing the transfer matrix method. Ultrathin silver can reduce the deadzone effect compared with graphene and PH1000, and leads to a factor of 1.07 enhancement for an electrical field in a metal microcavity. The enhancement is considered to be the fact that strong exciton-photon coupling occurs in the microcavity due to ultrathin Ag. On the basis of the optical enhancement effect, optical behaviors are manipulated by varying the microcavity length. It is confirmed that ultrathin silver can serve as an ideal interconnection layer as the active layer is ∼150 nm thick and the thickness ratio between front and rear active layers lies between 1:1 and 1:2. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which discusses a study related to 75 cases of primary gastric diffuse large B cell lymphoma (PG-DLBCL) in China.