46 research outputs found

    Environmental Air Pollution and the Risk of Osteoporosis and Bone Fractures

    Get PDF

    Efficient Vortex-assisted Extraction of Phorbol Esters from Jatropha Leaves and Correlation Between Leaves and Seeds in Phorbol EstersContent

    Get PDF
    This work aimed to optimise and validate the vortex-assisted extraction with high-performance liquid chromatography ultraviolet detection (HPLC-UV) method to quantify phorbol esters (PEs) in  Jatropha leaves. Additionally, to evaluate the correlation between PEs content in leaves and seeds. The results  of PEs content were expressed as equivalent of the major Jatropha phorbol ester, 12-deoxy-16-hydroxyphorbol-4’-[12’,14’-butadienyl]-6’-[16’,18’,20’-  nonatrienyl]-bicyclo[3.1.0]-hexane- (13-O)-2’-[carboxylate]-(16-O)-3’-]8’-butenoic-10’]ate (DHPB) . One-variable-at-time strategy and 25−1 V factorial  fractional design were employed to determine the effects of solvent type, volume, stirring frequency, extraction time and cycles on yield. The  quantification was performed using HPLC-UV. The optimum conditions were three extractions with 2% tetrahydrofuran:dichloromethane (1:1) in  methanol (THF:DCM/MeOH). The sample:solvent ratio was 1 mg:25 µL, and the vortex stirring was 2200 rpm for 5 minutes. The method showed good  linearity (R2 0.999), recoveries (97 to 105%), selectivity and repeatability (RSD 1.93-7.95%). In addition, good limits of detection and quantification of 2.19  and 6.65 ng µL−1, respectively, were noted. DHPB content in leaves and seeds ranged from 0.01 to 0.38 mg g−1 and 0.41 to 1.82 mg g−1, respectively.  There is a statistically significant and positive linear relationship between leaves and seeds for DHPB content. These results may have practical application  in analysing and predicting the amount of PEs in Jatropha leaves for environmental safety studies and the selection of better varieties for  genetic improvement. &nbsp

    Characterisation of Ppy-lineage cells clarifies the functional heterogeneity of pancreatic beta cells in mice

    Get PDF
    Aims/hypothesis Pancreatic polypeptide (PP) cells, which secrete PP (encoded by the Ppy gene), are a minor population of pancreatic endocrine cells. Although it has been reported that the loss of beta cell identity might be associated with beta-to-PP cell-fate conversion, at present, little is known regarding the characteristics of Ppy-lineage cells. Methods We used Ppy-Cre driver mice and a PP-specific monoclonal antibody to investigate the association between Ppy-lineage cells and beta cells. The molecular profiles of endocrine cells were investigated by single-cell transcriptome analysis and the glucose responsiveness of beta cells was assessed by Ca2+ imaging. Diabetic conditions were experimentally induced in mice by either streptozotocin or diphtheria toxin. Results Ppy-lineage cells were found to contribute to the four major types of endocrine cells, including beta cells. Ppy-lineage beta cells are a minor subpopulation, accounting for 12–15% of total beta cells, and are mostly (81.2%) localised at the islet periphery. Unbiased single-cell analysis with a Ppy-lineage tracer demonstrated that beta cells are composed of seven clusters, which are categorised into two groups (i.e. Ppy-lineage and non-Ppy-lineage beta cells). These subpopulations of beta cells demonstrated distinct characteristics regarding their functionality and gene expression profiles. Ppy-lineage beta cells had a reduced glucose-stimulated Ca2+ signalling response and were increased in number in experimental diabetes models. Conclusions/interpretation Our results indicate that an unexpected degree of beta cell heterogeneity is defined by Ppy gene activation, providing valuable insight into the homeostatic regulation of pancreatic islets and future therapeutic strategies against diabetes

    The Japanese space gravitational wave antenna; DECIGO

    Get PDF
    DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the future Japanese space gravitational wave antenna. DECIGO is expected to open a new window of observation for gravitational wave astronomy especially between 0.1 Hz and 10 Hz, revealing various mysteries of the universe such as dark energy, formation mechanism of supermassive black holes, and inflation of the universe. The pre-conceptual design of DECIGO consists of three drag-free spacecraft, whose relative displacements are measured by a differential Fabry– Perot Michelson interferometer. We plan to launch two missions, DECIGO pathfinder and pre- DECIGO first and finally DECIGO in 2024

    DECIGO pathfinder

    Get PDF
    DECIGO pathfinder (DPF) is a milestone satellite mission for DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) which is a future space gravitational wave antenna. DECIGO is expected to provide us fruitful insights into the universe, in particular about dark energy, a formation mechanism of supermassive black holes, and the inflation of the universe. Since DECIGO will be an extremely large mission which will formed by three drag-free spacecraft with 1000m separation, it is significant to gain the technical feasibility of DECIGO before its planned launch in 2024. Thus, we are planning to launch two milestone missions: DPF and pre-DECIGO. The conceptual design and current status of the first milestone mission, DPF, are reviewed in this article

    Current status of space gravitational wave antenna DECIGO and B-DECIGO

    Get PDF
    Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) is the future Japanese space mission with a frequency band of 0.1 Hz to 10 Hz. DECIGO aims at the detection of primordial gravitational waves, which could be produced during the inflationary period right after the birth of the universe. There are many other scientific objectives of DECIGO, including the direct measurement of the acceleration of the expansion of the universe, and reliable and accurate predictions of the timing and locations of neutron star/black hole binary coalescences. DECIGO consists of four clusters of observatories placed in the heliocentric orbit. Each cluster consists of three spacecraft, which form three Fabry-Perot Michelson interferometers with an arm length of 1,000 km. Three clusters of DECIGO will be placed far from each other, and the fourth cluster will be placed in the same position as one of the three clusters to obtain the correlation signals for the detection of the primordial gravitational waves. We plan to launch B-DECIGO, which is a scientific pathfinder of DECIGO, before DECIGO in the 2030s to demonstrate the technologies required for DECIGO, as well as to obtain fruitful scientific results to further expand the multi-messenger astronomy.Comment: 10 pages, 3 figure

    The status of DECIGO

    Get PDF
    DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) is the planned Japanese space gravitational wave antenna, aiming to detect gravitational waves from astrophysically and cosmologically significant sources mainly between 0.1 Hz and 10 Hz and thus to open a new window for gravitational wave astronomy and for the universe. DECIGO will consists of three drag-free spacecraft arranged in an equilateral triangle with 1000 km arm lengths whose relative displacements are measured by a differential Fabry-Perot interferometer, and four units of triangular Fabry-Perot interferometers are arranged on heliocentric orbit around the sun. DECIGO is vary ambitious mission, we plan to launch DECIGO in era of 2030s after precursor satellite mission, B-DECIGO. B-DECIGO is essentially smaller version of DECIGO: B-DECIGO consists of three spacecraft arranged in an triangle with 100 km arm lengths orbiting 2000 km above the surface of the earth. It is hoped that the launch date will be late 2020s for the present
    corecore