267 research outputs found

    Statistical modeling of texture sketch

    Get PDF
    Abstract. Recent results on sparse coding and independent component analysis suggest that human vision first represents a visual image by a linear superposition of a relatively small number of localized, elongate, oriented image bases. With this representation, the sketch of an image consists of the locations, orientations, and elongations of the image bases, and the sketch can be visually illustrated by depicting each image base by a linelet of the same length and orientation. Built on the insight of sparse and independent component analysis, we propose a two-level generative model for textures. At the bottom-level, the texture image is represented by a linear superposition of image bases. At the top-level, a Markov model is assumed for the placement of the image bases or the sketch, and the model is characterized by a set of simple geometrical feature statistics

    Mach cone induced by γ\gamma-triggered jets in high-energy heavy-ion collisions

    Full text link
    MMedium excitation by jet shower propagation inside a quark-gluon plasma is studied within a linear Boltzmann transport and a multiphase transport model. Contrary to the naive expectation, it is the deflection of both the jet shower and the Mach-cone-like excitation in an expanding medium that is found to gives rise to a double-peak azimuthal particle distribution with respect to the initial jet direction. Such deflection is the strongest for hadron-triggered jets which are often produced close to the surface of dense medium due to trigger-bias and travel against or tangential to the radial flow. Without such trigger bias, the effect of deflection on γ\gamma-jet showers and their medium excitation is weaker. Comparative study of hadron and γ\gamma-triggered particle correlations can therefore reveal the dynamics of jet-induced medium excitation in high-energy heavy-ion collisions.Comment: 4 pages in RevTeX with 5 figures, finally version in PR

    3-Mesityl-2-oxo-1-oxaspiro­[4.4]non-3-en-4-yl 4-chloro­benzoate

    Get PDF
    The title compound, C24H23ClO4, is a potent insecticide and miticide. The five-membered cyclo­pentane ring displays an envelope conformation with the atom at the flap position 0.611 (2) Å out of the mean plane formed by the other four atoms. The furan ring makes dihedral angles of 71.3 (2) and 81.9 (2)°, respectively, with the 2,4,6-trimethyl­phenyl and 4-chloro­phenyl rings. The dihedral angle between the two benzene rings is 76.6 (1)°. In the crystal, mol­ecules are linked through weak inter­molecular C—H⋯O hydrogen bonds, forming chains running along the c axis

    4-Hydr­oxy-3-mesityl-1-oxaspiro­[4.4]non-3-en-2-one

    Get PDF
    In the title compound, C17H20O3, the five-membered cyclo­pentyl ring displays an envelope conformation, with the atom at the flap position 0.538 (3) Å out of the mean plane formed by the other four atoms. The dihedral angle between the benzene and furan rings is 63.34 (15)°. In the crystal structure, mol­ecules are linked through inter­molecular O—H⋯O hydrogen bonds, forming a zigzag chain along [101]

    2-(4-Chloro­phen­yl)-3-methyl-N-(5-methyl­thia­zol-2-yl)butanamide

    Get PDF
    In the title compound, C15H17ClN2OS, the thia­zole ring, which is essentially planar with a maximum deviation of 0.044 (3) Å, makes a dihedral angle of 54.76 (8)° with the benzene ring. In the crystal, adjacent molecules related by twofold rotation symmetry are linked by pairs of N—H⋯N hydrogen bonds

    3-(2,4-Dichloro­phen­yl)-2-oxo-1-oxa­spiro­[4.5]dec-3-en-4-yl 4-chloro­benzoate

    Get PDF
    In the title spiro­diclofen derivative, C22H17Cl3O4, the cyclo­hexane ring adopts a chair conformation [four C atoms are planar with a mean deviation of 0.018 Å and the two C atoms at the flap positions deviate by 0.613 (4) and −0.668 (5) Å from the plane]. The dihedral angles between the furan ring and the two benzene rings are 55.78 (3) and 49.92 (3)°. Weak inter­molecular C—H⋯Cl inter­actions are observed in the crystal structure

    Propofol exhibits inhibitory effect towards human liver microsomes (HLMs)- catalyzed glucuronidation of thienorphine

    Get PDF
    Drug-drug interaction (DDI) is a challenging problem in the process of drug utilization. Inhibition of glucuronidation reaction of drugs is a major reason for DDI. The aim of the present study is to predict propofol-thienorphine interaction from the perspective of propofol’s inhibition towards thienorphine glucuronidation. The human liver microsomes (HLMs) incubation system supplemented with uridine 5’-diphosphoglucuronic acid (UDPGA) was used. The results showed that propofol inhibited HLMscatalyzed thienorphine glucuronidation in a concentration-dependent manner. Both Dixon plot and Lineweaver-Burk plot showed that the inhibition of thienorphine glucuronidation by propofol was best fit to competitive inhibition, and the second plot using slopes from Lineweaver-Burk plot versus thienorphine concentration was used to determine the inhibition kinetic parameter (Ki ) value to be 365.9 μM. Whether the in vitro inhibition of propofol towards thienorphine glucuronidation can induce the in vivo propofolthienorphine interaction might be influenced by many factors, including various pharmacokinetic factors influencing the in vivo concentration of propofol. These data should be carefully explained due to complicated factors influencing the in vitro-in vivo extrapolation (IVIVE) results.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Hydrogen sulfide attenuates cardiac dysfunction in a rat model of heart failure: a mechanism through cardiac mitochondrial protection

    Get PDF
    HF (heart failure) after MI (myocardial infarction) is a major cause of morbidity and mortality worldwide. Recent studies have shown that hydrogen sulfide (H2S) has cardioprotective effects. Hence, we aimed to elucidate the potential effects of H2S on HF after MI in rats. The HF model after MI was made by ligating the left anterior descending coronary artery. HF groups and sham-operated groups of rats were treated with vehicle, sodium hydrosulfide (NaHS) or PAG (propagylglycine). Equal volumes of saline, 3.136 mg·kg−1·day−1 NaHS or 37.5 mg·kg−1·day−1 PAG, were intraperitoneally injected into rats for 6 weeks after operation. Survival, lung-to-body weight ratio and left ventricular haemodynamic parameters were measured. The protein and gene expression of Bcl-2, Bax, caspase 3 and cytochrome c were analysed by Western blotting and RT–PCR (reverse transcription–PCR). TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling) and EM (electron microscopy) were used to examine apoptosis of heart tissues. NaHS was found to improve the survival and lower the lung-to-body weight ratio. It increased the LVSP (left ventricular systolic pressure) and the maximum rate of pressure and decreased LVEDP (left ventricular end-diastolic pressure). Furthermore, NaHS promoted Bcl-2 protein and mRNA expression and demoted Bax, caspase 3 protein and mRNA expression in HF rats. We also showed that NaHS decreased the leakage of cytochrome c protein from the mitochondria to the cytoplasm. Histological observation by TUNEL and EM proved that NaHS inhibited cardiac apoptosis in HF hearts and improved mitochondrial derangements, but that PAG aggravated those indices. Hence, H2S has protective effects in HF rats

    3D Printing‐Enabled Design and Manufacturing Strategies for Batteries: A Review

    Get PDF
    Lithium-ion batteries (LIBs) have significantly impacted the daily lives, finding broad applications in various industries such as consumer electronics, electric vehicles, medical devices, aerospace, and power tools. However, they still face issues (i.e., safety due to dendrite propagation, manufacturing cost, random porosities, and basic & planar geometries) that hinder their widespread applications as the demand for LIBs rapidly increases in all sectors due to their high energy and power density values compared to other batteries. Additive manufacturing (AM) is a promising technique for creating precise and programmable structures in energy storage devices. This review first summarizes light, filament, powder, and jetting-based 3D printing methods with the status on current trends and limitations for each AM technology. The paper also delves into 3D printing-enabled electrodes (both anodes and cathodes) and solid-state electrolytes for LIBs, emphasizing the current state-of-the-art materials, manufacturing methods, and properties/performance. Additionally, the current challenges in the AM for electrochemical energy storage (EES) applications, including limited materials, low processing precision, codesign/comanufacturing concepts for complete battery printing, machine learning (ML)/artificial intelligence (AI) for processing optimization and data analysis, environmental risks, and the potential of 4D printing in advanced battery applications, are also presented

    Dynamic hydraulic jump and retrograde sedimentation in an open channel induced by sediment supply: experimental study and SPH simulation

    Get PDF
    Mountainous torrents often carry large amounts of loose materials into the rivers, thus causing strong sediment transport. Experimentally it was found for the first time that when the intensive sediment motion occurs downstream over a gentle slope, the siltation of the riverbed is induced and the sediment particles can move upstream rapidly in the form of a retrograde sand wave, resulting in a higher water level along the river. To further study the complex mechanisms of this problem, a sediment mass model in the framework of the Smoothed Particle Hydrodynamics (SPH) method was presented to simulate the riverbed evolution, sediment particle motion, and the generation and development of dynamic hydraulic jump under the condition of sufficient sediment supply over a steep slope with varying angles. Because the sediment is not a continuous medium, the marker particle tracking approach was proposed to represent a piece of sediment with a marked sediment particle. The two-phase SPH model realizes the interaction between the sediment and fluid by moving the bed boundary particles up and down, so it can reasonably treat the fluid-sediment interfaces with high CPU efficiency. The critical triggering condition of sediment motion, the propagation of the hydraulic jump and the initial siltation position were all systematically studied. The experimental and numerical results revealed the extra disastrous sediment effect in a mountainous flood. The findings will be useful references to the disaster prevention and mitigation in mountainous rivers
    corecore