50 research outputs found

    Analysis of Laboratory Experimental Tests on Mixed Oil Disposal (Bilge) from Ships Based on Marpol Annex I: A Case Study of Port of Tanjung Mas Semarang and Port of Tegal

    Get PDF
    Management of marine pollution is a difficult condition to realize, especially the pollution of mixed oil disposal (bilge) resulting from the operation of ships. The oil component has different characteristics compared to the essence of other substances; namely, oil can float on the surface of the water because it has an extra weight the type/density of the essence. The parameters tested in this research are oil/fat content parameters and their extraction according to National Certification Institution 6989.59:2008. Bilge water samples were taken from five commercial ships that leaned on the port and then carried out pre-treatment and post-treatment tests with the liquid separation process in the Oil Water Separator (OWS) device on the ship and then tested in the laboratory to determine the infrared spectrum in the absorption of oil content emissions in water samples, which may not exceed the standard threshold for port water quality, i.e., 5 mg.L-1. The sampling tests were carried out for the variables temperature, pH, Total Dissolved Solid (TDS), and oil content obtained values were below the threshold for water quality. To find out the relationship between Group I and Group II, linear regression was used showing the Ho result in reject (0.000<0.05), which means there is a significant relationship between Group I and II

    Abiotic Stresses Tolerance and Nutrients Contents in Groundnut, Pearl Millet and Sorghum Mini Core Collections for Food and Nutrition Security

    Get PDF
    Food and nutrition security still require new sources of tolerance to major abiotic stresses and high nutritional quality. Groundnut, pearl millet and sorghum mini core collections are representing diversity of global collections but few studies investigated the nutrients contents and the tolerance to low phosphorus (LP) and drought stress (WS). Under lysimetre and pots conditions, subsets of these mini core collections were used to assess genotypic variation in nutrients contents and identify new sources of tolerance to WS and LP. In a randomized completely block design with 5 replications, water regimes and phosphorus treatments were imposed. Agromorphological and nutrients contents parameters were investigated. ANOVA were performed to assess the genotype and treatments effects. WS decreased the transpiration efficiency (47%), yield and its components (68%) in groundnut. Combined WS-LP reduced pods weight (83%). ICG3312, ICG81, ICG13395 and ICG467 revealed tolerant to WS/LP. In Pearl millet, LP decreased 100 seeds weight (14%), panicle and shoot biomass weight (25%), the booting date delayed except on IP1060, IP5869, IP9000, IP17532 and IP17775. WS-LP decreased total biomass (35%) while LP reduced total N(4.5%), P(20%), K(23%), Fe(25%) and Zn(3%). IP17532, IP 5153 and IP 5581 revealed highest Fe content (524mgkg-1). In sorghum, LP delayed the booting date, decreased biomass (32%) and WS-LP reduced biomass (74%). ISS2151, ISS705 and ISS862 revealed tolerant to WS-LP. LP decreased total N(11%), P(32%), K(13%), Fe(13%) and Zn(11%). IS1412, IS311 and IS376 showed high Fe content (515mgKg-1). Selected genotypes and traits might be useful in crops improvement for more adaptation and productivity

    Femtosecond x-ray diffraction from an aerosolized beam of protein nanocrystals

    Get PDF
    We demonstrate near-atomic-resolution Bragg diffraction from aerosolized single granulovirus crystals using an x-ray free-electron laser. The form of the aerosol injector is nearly identical to conventional liquid-microjet nozzles, but the x-ray-scattering background is reduced by several orders of magnitude by the use of helium carrier gas rather than liquid. This approach provides a route to study the weak diffuse or lattice-transform signal arising from small crystals. The high speed of the particles is particularly well suited to upcoming MHz-repetition-rate x-ray free-electron lasers

    Coherent diffraction of single Rice Dwarf virus particles using hard X-rays at the Linac Coherent Light Source

    Get PDF
    Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a wellcharacterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and injected into the approximately 0.1 mu m diameter focused hard X-ray beam at the CXI instrument of LCLS. Diffraction patterns from RDV with signal to 5.9 angstrom ngstrom were recorded. The diffraction data are available through the Coherent X-ray Imaging Data Bank (CXIDB) as a resource for algorithm development, the contents of which are described here.11Ysciescopu

    On the use of multilayer Laue lenses with X-ray Free Electron Lasers

    Get PDF
    Multilayer Laue lenses were used for the first time to focus x-rays from an X-ray Free Electron Laser (XFEL). In an experiment, which was performed at the European XFEL, we demonstrated focusing to a spot size of a few tens of nanometers. A series of runs in which the number of pulses per train was increased from 1 to 2, 3, 4, 5, 6, 7, 10, 20 and 30 pulses per train, all with a pulse separation of 3.55 us, was done using the same set of lenses. The increase in the number of pulses per train was accompanied with an increase of x-ray intensity (transmission) from 9% to 92% at 5 pulses per train, and then the transmission was reduced to 23.5 % when the pulses were increased further. The final working condition was 30 pulses per train and 23.5% transmission. Only at this condition we saw that the diffraction efficiency of the MLLs changed over the course of a pulse train, and this variation was reproducible from train to train. We present the procedure to align and characterize these lenses and discuss challenges working with the pulse trains from this unique x-ray source

    Eliminating Malaria Vectors.

    Get PDF
    Malaria vectors which predominantly feed indoors upon humans have been locally eliminated from several settings with insecticide treated nets (ITNs), indoor residual spraying or larval source management. Recent dramatic declines of An. gambiae in east Africa with imperfect ITN coverage suggest mosquito populations can rapidly collapse when forced below realistically achievable, non-zero thresholds of density and supporting resource availability. Here we explain why insecticide-based mosquito elimination strategies are feasible, desirable and can be extended to a wider variety of species by expanding the vector control arsenal to cover a broader spectrum of the resources they need to survive. The greatest advantage of eliminating mosquitoes, rather than merely controlling them, is that this precludes local selection for behavioural or physiological resistance traits. The greatest challenges are therefore to achieve high biological coverage of targeted resources rapidly enough to prevent local emergence of resistance and to then continually exclude, monitor for and respond to re-invasion from external populations

    3D diffractive imaging of nanoparticle ensembles using an X-ray laser

    Get PDF
    We report the 3D structure determination of gold nanoparticles (AuNPs) by X-ray single particle imaging (SPI). Around 10 million diffraction patterns from gold nanoparticles were measured in less than 100 hours of beam time, more than 100 times the amount of data in any single prior SPI experiment, using the new capabilities of the European X-ray free electron laser which allow measurements of 1500 frames per second. A classification and structural sorting method was developed to disentangle the heterogeneity of the particles and to obtain a resolution of better than 3 nm. With these new experimental and analytical developments, we have entered a new era for the SPI method and the path towards close-to-atomic resolution imaging of biomolecules is apparent

    Femtosecond X-ray diffraction from an aerosolized beam of protein nanocrystals

    Get PDF
    High-resolution Bragg diffraction from aerosolized single granulovirus nanocrystals using an X-ray free-electron laser is demonstrated. The outer dimensions of the in-vacuum aerosol injector components are identical to conventional liquid-microjet nozzles used in serial diffraction experiments, which allows the injector to be utilized with standard mountings. As compared with liquid-jet injection, the X-ray scattering background is reduced by several orders of magnitude by the use of helium carrier gas rather than liquid. Such reduction is required for diffraction measurements of small macromolecular nanocrystals and single particles. High particle speeds are achieved, making the approach suitable for use at upcoming high-repetition-rate facilities.Use of the Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under contract No. DE-AC02-76SF00515. Parts of the sample delivery system used at LCLS for this research were funded by the NIH grant P41GM103393, formerly P41RR001209. In addition to DESY, this work has been supported by the excellence cluster ‘The Hamburg Center for Ultrafast Imaging – Structure, Dynamics and Control of Matter at the Atomic Scale’ of the Deutsche Forschungsgemeinschaft (CUI, DFG-EXC1074), the Gottfried Wilhelm Leibniz Program of the DFG, the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007–2013) through the Synergy Grant AXSIS (ERC-2013-SyG 609920) and the Consolidator Grant COMOTION (ERC-Ku¨pper-614507), the Helmholtz Association ‘Initiative and Networking Fund’, and the Australian Research Council’s Discovery Projects funding scheme (DP170100131). RAK acknowledges support from an NSF STC award (1231306)

    Catalytic cleavage of HEAT and subsequent covalent binding of the tetralone moiety by the SARS-CoV-2 main protease

    Get PDF
    Here we present the crystal structure of SARS-CoV-2 main protease (Mpro) covalently bound to 2-methyl-1-tetralone. This complex was obtained by co-crystallization of Mpro with HEAT (2-(((4-hydroxyphenethyl)amino)methyl)-3,4-dihydronaphthalen-1(2H)-one) in the framework of a large X-ray crystallographic screening project of Mpro against a drug repurposing library, consisting of 5632 approved drugs or compounds in clinical phase trials. Further investigations showed that HEAT is cleaved by Mpro in an E1cB-like reaction mechanism into 2-methylene-1-tetralone and tyramine. The catalytic Cys145 subsequently binds covalently in a Michael addition to the methylene carbon atom of 2-methylene-1-tetralone. According to this postulated model HEAT is acting in a pro-drug-like fashion. It is metabolized by Mpro, followed by covalent binding of one metabolite to the active site. The structure of the covalent adduct elucidated in this study opens up a new path for developing non-peptidic inhibitors
    corecore