Diaporindenes A-D (1-4), four unusual 2,3-dihydro-1 H-indene isomers, a novel isoprenylisobenzofuran A (5), two new isoprenylisoindole alkaloids diaporisoindoles D and E (6 and 7), and a new benzophenone derivative tenellone D (11), together with four known biogenetic agents (8-10 and 12), were all separated from the endophytic fungus Diaporthe sp. SYSU-HQ3 guided by ultraperformance liquid chromatography high-resolution mass spectrometry. The absolute configurations of 1-7 and 11 were defined by X-ray diffraction, quantum chemical calculations, and spectroscopic analysis. Diaporindenes A-D (1-4) possessed an unprecedented chemical skeleton featuring a 2,3-dihydro-1 H-indene ring and a 1,4-benzodioxan moiety. All of the isolates (1-12) were tested for their inhibitory effects on the production of nitric oxide in lipopolysaccharide-induced microglial cells (RAW 264.7 cells). Compounds 1-5, 8, and 9 were found to exhibit significant inhibitory effects against nitric oxide production with IC values from 4.2 to 9.0 μM and SI values from 3.5 to 6.9. In addition, the structure-activity relationships of all compounds were summarized.

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Abstract:The genus Tephrosia, belonging to the Leguminosae family, is a large pantropical genus of more than 350 species, many of which have important traditional uses in agriculture because they possess the bioactivity of phytoalexins. This review not only outlines the sources, chemistry and biological evaluations of natural products from the genus Tephrosia worldwide that have appeared in literature from 1910 to December 2013, but also covers work related to proposed biosynthetic pathways and synthesis of some natural products from the genus Tephrosia, with 105 citations and 168 new compounds.

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A pair of enantiomeric indole diketopiperazine alkaloid dimers [(−)- and (+)-asperginulin A (1a and 1b)] with an unprecedented 6/5/4/5/6 pentacyclic skeleton were isolated from the mangrove endophytic fungus Aspergillus sp. SK-28. The enantiomeric dimers were separated by chiral-phase HPLC. Their structures including absolute configurations were elucidated by spectroscopic analysis, X-ray diffraction, and quantum chemical calculation. (+)-Asperginulin A (1b) exhibited antifouling activity against the barnacle Balanus reticulatus.

The well-known size exclusion chromatography (SEC) universal calibration allows the characterization of a polymer sample using a set of polymer standards of a different polymer family. This is a polymer-transferable calibration method. A more “universal” calibration method has been proposed for thermal field-flow fractionation (ThFFF) where the calibration constants closely describe the ratio of ordinary (molecular) diffusion coefficient D to thermal diffusion coefficient (or, more correctly, thermophoretic mobility) D T. The universal calibration for ThFFF is therefore instrument or system transferable. Systematic experiments have previously been carried out to verify this calibration method for a wide range of conditions. Results showed that the method holds well provided experimental conditions such as sample size and cold wall temperature T c are the same for each system. This paper quantifies the effect of cold wall temperature on polymer retention in ThFFF and on the universal calibration constants for the polystyrene−tetrahydrofuran, poly(methyl methacrylate)−tetrahydrofuran, and polyisoprene−tetrahydrofuran systems, respectively. The universal calibration for ThFFF is thereby extended to account for variation of cold wall temperature. The extended calibration will allow for accurate data retrieval from analyses obtained at any cold wall temperature. It will even allow for accurate information retrieval when cold wall temperature is not held constant during sample elution, such as may occur with a change in coolant flow rate or with a programmed decay of Δ T.

Abstract:Critical mining under buildings, railways, and water bodies (BRW) brings the contradiction between high recovery rate and minor environmental hazards. To lessen this contradiction, an innovative mining method referred to as "wide strip backfill mining" (WSBM) was proposed in this study. A Winkler beam model is applied to the primary key strata (PKS), and the study revealed a surface subsidence control mechanism and designed the technical parameters of the method. The respective numerical simulations suggested the feasibility of the proposed method and the main influencing factors on surface subsidence can be ranked in descending order as wide filling strip width (WFSW), filling ratio, and pillar width. Meanwhile, a drop in the WFSW from 96 m to 72 m brought out the surface subsidence reduction by 44.5%. By using the super-high water content filling material, the proposed method was applied in the Taoyi coal mine under critical mining conditions. The resulting surface subsidence and deformations met the safety requirements for building protection level 1, and the recovery rate reached 75.9%. Moreover, the application of the method achieved significant technical and economic benefits. The research can provide a theoretical and experimental substantiation for critical mining under BRW.

A reference interval provides a basis for physicians to determine whether a measurement is typical of a healthy individual. It can be interpreted as a prediction interval for a new individual from the overall population. However, a reference interval based on a single study may not be representative of the broader population. Meta‐analysis can provide a general reference interval based on the overall population by combining results from multiple studies. Methods for estimating the reference interval from a random effects meta‐analysis have been recently proposed to incorporate the within and between‐study variation, but a random effects model may give imprecise estimates of the between‐study variation with only few studies. In addition, the normal distribution of underlying study‐specific means, and equal within‐study variance assumption in these methods may be inappropriate in some settings. In this article, we aim to estimate the reference interval based on the fixed effects model assuming study effects are unrelated, which is useful for a meta‐analysis with only a few studies (e.g., ≤5). We propose a mixture distribution method only assuming parametric distributions (e.g., normal) for individuals within each study and integrating them to form the overall population distribution. This method is compared to an empirical method only assuming a parametric overall population distribution. Simulation studies have shown that both methods can estimate a reference interval with coverage close to the targeted value (i.e., 95%). Meta‐analyses of women daytime urination frequency and frontal subjective postural vertical measurements are reanalyzed to demonstrate the application of our methods.