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Two new compounds, including one meroterpenoid (1) and a polyketide derivative (2), along with six compounds (3 − 8), were isolated from the rice solid fermentation of Penicillium expansum GY618. The structures of these new compounds were elucidated through interpretations of spectroscopic data and highresolution electrospray ionization mass spectrometry. The absolute configurations of all new compounds were unambiguously established through the optical rotation or calculation of the ECD spectrum. All isolated compounds were evaluated for their antibacterial and antitumor activities. Compound 6 exhibited weak antitumor activity. [Display omitted] • One new meroterpenoid and a new polyketide derivative were isolated. • The absolute configuration of all new compounds was unambiguously established. • Compound 6 showed weak antitumor activity. [ABSTRACT FROM AUTHOR]

The physical properties of natural gas hydrate-bearing sediments are critical for the analysis of natural systems and for the design of gas production strategies. This work explores the properties of fine-grained sediments containing segregated hydrate lenses. Our analyses show that hydrate formation is grain-displacive when the product of the effective stress and the grain radius is σ′R < 2π Γ hw ≈ 0.2-to-0.3 N/m, such as in shallow fine-grained sediments. The assessment of physical properties is particularly challenging in fine-grained sediments with segregated gas hydrate because (1) inherent difficulties in hydrate formation hinder laboratory studies, and (2) segregated hydrate requires large specimens and laboratory devices to avoid boundary effects and to create a representative volume for analysis. We circumvent these challenges through the use of numerical simulations. In these simulations, the properties of the hydrate-free sediment surrounding the segregated hydrate lenses take into consideration the effects of cryogenic suction and grain-displacive hydrate growth. Our results for mechanical properties and conduction show that numerical simulations must properly consider the hydrate morphology, the altered sediment properties, and the sediment-hydrate interfacial conditions (interfaces are rough, jagged and well bonded during hydrate formation, but become weak-frictional on dissociation). In fact, changes in the strength and stiffness of the hydrate-free sediment that surrounds a segregated hydrate mass can be more important on the global properties than the presence of hydrate itself. Numerical simulations highlight distinct anisotropy in mechanical properties and conduction in the presence of segregated hydrate lenses, and the tendency to shear localization when there is a weak-frictional interface. We emphasize that a relatively small fraction of fines can make sediments prone to segregated hydrate formation, therefore proper sediment classification is critical. • Particle-displacive hydrate formation compacts the surrounding sediment and alters its physical properties. • Theoretical and numerical approaches must consider hydrate morphology and altered properties of surrounding sediments. • Segregated hydrate lenses results in distinct anisotropy in conduction and mechanical properties. [ABSTRACT FROM AUTHOR]

This paper measures the regional oceanic economic performance in China's 11 coastal areas from 2007 to 2014 using a dynamic growth efficiency framework. We construct a new global Malmquist ocean performance index (GMOPI), which integrates the global benchmark technology with the slacks-based measure (SBM) and Malmquist-Luenberger (ML) productivity index. This index can successfully eliminate a common infeasibility problem encountered in ML cross-period problem. Furthermore, the labour input, capital input, economic output, and environmental output contribution indexes are proposed by internally decomposing the GMOPI, which can explain which factor could bias technological progress. The empirical results indicate two different modes of China's oceanic economic growth during the examined time period, i.e., a volatility phase (2007–2010) and a stability phase (2011–2014). Moreover, the factor contribution indexes show that the low contribution scores for environmental integrity and capital in the volatility phase. The findings highlight the need for the further strengthening of environmental and investment policies in China. • China's ocean economy performance depends on environmental integrity was examined. • The four factor contributions to GMOPI are explored. • The empirical results indicated two phases of China's ocean economy. • The findings will call for further strengthening of the coordination of environmental policies in China. [ABSTRACT FROM AUTHOR]

Describing the pore habit of methane hydrate in sediment matrices is essential for understanding natural distribution of methane hydrate, methane trace (transport and solidification) in the hydrate stability zone, physical properties of hydrate-bearing sediments, and the associated influence on potential gas production. Pore habit visualization in natural media at pore scale even with laboratory synthesized cores has been challenging due to the similar densities of methane hydrate from pore liquid. In this work, we used phase-contrast assisted micro-CT with potassium iodine-doped brine to visualize four phases: sand particles, pore fluid, methane hydrate and methane gas. This study visualizes the pore habit of methane hydrate at various stages including during hydrate formation in excess-gas systems, its evolution after brine injection to replace pore fluid, and hydrate formation in excess-water systems. Hydrate tends to adopt round and smooth surfaces when in contact with water while exhibits relatively angular interfaces when in contact with methane gas. Hydrate formation in excess-gas systems results in a partial cementing and partial mineral-coating pore habit, while hydrate in excess-water systems develops mainly as pore-filling, and locally cementing or mineral-coating where big gas pockets exist at the initial state. Pore liquid replacement from methane gas to brine triggers a shift of hydrate pore habit towards pore-filling. Methane hydrate evolution over time produces bigger hydrate particles but with less contact area with sand particles. The effects of hydrate pore habit become less important as hydrate particle size exceeds the pore size. Additionally, hydrate formation could trap residual methane gas and brine as inclusions. • Excess-gas systems host primarily cementing and mineral-coating hydrate. • Excess-water systems develop mainly pore-filling hydrate. • Brine injection into excess-gas systems shifts pore habits towards pore-filling. • The affinity to quartz sand surface follows the order: water > hydrate > gas. • Natural gas hydrate could be: round, similar in size, mainly pore-filling. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) was modified with poly (butylene adipate- co -terephthalate) (PBAT) and carbon nanotubes (CNTs-COOH) with carboxyl groups by using the melt blending technique. Ethylene-butyl acrylate-glycidyl methacrylate (E-BA-GMA) was used as a compatibilizer which can bond the CNTs-COOH nanoparticles with PLA/PBAT matrix through interaction between the epoxy and carboxyl groups. The effects of the CNTs-COOH content on the mechanical properties, thermal properties, crystallinity and morphology of PLA/CNTs-COOH nanocomposites were investigated. The results showed that the tensile strength, elongation at break and impact strength of PLA could be simultaneously increased by incorporating CNTs-COOH nanoparticles. PLA/CNTs-COOH nanocomposites possessed higher thermal stability than pure PLA. The glass transition temperature and initial degradation temperature of PLA/CNTs-COOH increased as the CNTs-COOH content increased. When the CNTs-COOH content was low (≤0.5 wt%), CNTs-COOH nanoparticles could uniformly disperse in the PLA matrix. In general, CNTs-COOH was an effective filler to reinforce and toughen PLA simultaneously, and the PLA/CNTs-COOH nanocomposite with 0.5 wt% CNTs-COOH exhibited a good combination of strength and toughness. [ABSTRACT FROM AUTHOR]

Glare reduction is the focus of much attention in the field of optical engineering owing to its vital role in high-quality image acquisition in photoelectric visual inspection technology. Based on Fresnel reflection theory, we have derived a polarization factor related to the glare intensity distribution and have obtained theoretical results showing that the factor plays a leading role in reducing glare. Based on the image detection model, we have derived a displacement factor which determines the position and the size of the glare area, and have obtained theoretical results showing that the factor plays a supporting role in reducing glare. The image gray-scale transformation curve is obtained by sampling image data under the different polarization and positions. And these image data are measured from certain object in the equivalent environment while the different conditions. Then the theories above have been justified and the whole theory of the polarization-based glare elimination method has been interpreted completely via actual experiments in glare elimination. As a result, reducing the intensity contrast between the glare area and its neighboring area is proved to be the essence of glare elimination. Furthermore, the glare can be nearly eliminated perfectly by adjusting the polarization factor and the displacement factor. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) was modified by poly (butylene adipate- co -terephthalate) (PBAT) and nano-attapulgite (AT) using the melt blending technique. Ethylene-butyl acrylate-glycidyl methacrylate (E-BA-GMA) was used as a compatibilizer which can bond the AT nanoparticles with PLA/PBAT matrix by interaction between the epoxy and hydroxyl groups. The effects of the AT content on the mechanical properties, thermal properties, crystallinity and morphology of PLA/PBAT/ATT nanocomposites were investigated. The results showed that the tensile strength, elongation at break and impact strength of PLA/PBAT could be simultaneously increased by incorporating AT nanoparticles. PLA/PBAT/AT nanocomposites possessed higher thermal stability than pure PLA/PBAT. In the ternary composite system of PLA/PBAT/AT, AT acted as a heterogeneous nucleating agent and was able to increase the crystallization temperature. When the AT content was low (≤2.5 wt%), AT nanoparticles could uniformly disperse in the PLA/PBAT matrix. In general, AT was an effective filler to reinforce and toughen PLA/PBAT blend simultaneously, and the PLA/PBAT/AT nanocomposite with 2.5 wt% AT exhibited a good combination of strength and toughness. [ABSTRACT FROM AUTHOR]

Banana fusarium wilt caused by Fusarium oxysporum f. sp. cubense race 1 (FOC1) and race 4 (FOC4) is a destructive disease that affects bananas in tropical and subtropical areas worldwide. A sensitive and specific detection method is the primary step to preventing spread of the disease. In this study, a real-time fluorescence PCR method was developed based on specific conserved primers from the markers of sequence characterized amplified region (SCAR) and TaqMan probes for detecting FOC1 and FOC4. The results showed that real-time fluorescence PCR could be used to detect FOC1 and FOC4 accurately and effectively within 90 min (not including DNA extraction). The developed method had high specificity and could therefore be used to distinguish F. oxysporum f. sp. cubense from other allied species and forma, such as Fusarium verticillioides , Fusarium oxysporum f. sp. melonis , Fusarium oxysporum f. sp. momodicae , Fusarium oxysporum f. sp. benincasae , and Fusarium oxysporum f. sp. opuntiarum , and other plant pathogens, such as Penicillium . This detection system also demonstrated high sensitivity, yielding a total copy number of 91,258, which was 100 times higher than that of endpoint PCR. We found that FOC1 had approximately 36 times higher abundance in banana ‘Guangfen #1’ pseudostem than FOC4 at 14 days after infection. In addition, banana ‘Guangfen #1’ root tissues showed an approximately 23 times higher abundance of FOC1 than corm tissues in field samples. In conclusion, the developed single-tube duplex real-time PCR method can sensitively distinguish FOC1 and FOC4 with high specificity. This method can be utilized to assist in the implementation of quarantine measures for the prevention and control of banana fusarium wilt caused by F. oxysporum f. sp. cubense . [ABSTRACT FROM AUTHOR]

We discuss the disadvantage in conventional Spectral Phase Interferometry for Direct Electric-field Reconstruction (SPIDER) technology in complex femtosecond pulse measurement. An improved version of conventional technology named DC-FISH is presented, where single replica of the unknown pulse upconverts synchronously with two frequency-shifted narrow-banded long pulses. The spectral phase of the unknown pulse can be directly calculated from the fringe-free spectra with the introduction of a suitable small delay between the upconverted pulses. The numerical simulation results are achieved to identify a higher efficiency and lower requirements on measurement in novel approach. [ABSTRACT FROM AUTHOR]

Abstract: To prevent the deleterious effects of antibiotic overuse, alternative strategies against microbial pathogens become essential in clinic surgeries. Thereinto, antibacterial inorganic coating materials have stimulated great interest recently. In this work, Ag–SiO2 composite films have been synthesized at room temperature (RT) using pulsed laser deposition, and the ratio of Ag and SiO2 in the films can be strictly controlled by tuning the Ag:SiO2 ablated area ratio of the target. The resultant films exhibit pronounced antibacterial properties against both gram-negative Escherichia coli (E. coli) and gram-positive Staphylococcus aureus (S. aureus). It is revealed that all films obtained are highly effective against S. aureus even at a low Ag:SiO2 ratio, while those with a larger Ag:SiO2 ratio can inhibit E. Coli more efficiently. This RT gas-phase deposition of Ag–SiO2 composite films can be universally applied on diverse substrates and may have promising applications as antibacterial coatings in orthopedic and dental surgeries. [Copyright &y& Elsevier]

Abstract: We describe a novel transmission grating with a connecting layer to achieve high efficiency diffraction with polarization-independence. The grating duty cycle and period are optimized by modal method. Accurate grating depth and connecting layer thickness are optimized using rigorous coupled-wave analysis. High efficiencies of 99.21% for TE polarization and 99.12% for TM polarization can be achieved with the optimized grating parameters. Furthermore, the grating with a connecting layer can show efficiencies larger than 97% for both TE and TM polarizations within the given range of grating depth and connecting layer thickness, which will be significant for practical applications of such a high-efficiency polarization-independent grating with a connecting layer. [Copyright &y& Elsevier]

Abstract: We describe a novel polarizing beam splitter (PBS) of transmission connecting-layer-based grating, which can show high efficiency for TE polarization in the −1st order and TM polarization in the 0th order. According to the modal method, grating duty cycle and period are prescribed to obtain high efficiency for TM polarization. Using the rigorous coupled-wave analysis, grating depth and thickness of the connecting layer are optimized to achieve high efficiency for TE polarization. The presented PBS has advantages of wideband properties for incident wavelength and angle. Most importantly, the efficiency is improved greatly for TE polarization compared with the reported PBS based on fused-silica grating. [Copyright &y& Elsevier]

Abstract: A shift- and scale-invariant version of morphological fringe-adjusted joint transform correlation (MFJTC) is proposed in this paper, which we call shift- and scale-invariant MFJTC (SIMFJTC). SIMFJTC is combination of MFJTC and conventional radial harmonic filter (RHF). Using computer simulation, we compare the output results of SIMFJTC with those of morphological radial harmonic correlation (MRHC) and SDF-based FPFJTC when input scene is corrupted by salt-and-pepper noise and cluttered background. Our results show that SIMFJTC has higher discriminability and displays better stability against salt-and-pepper noise and cluttered background. Moreover, scale-invariance of SIMFJTC is much stricter than MRHC and SDF-based FPFJTC. [Copyright &y& Elsevier]

Abstract: Pak4 is a member of the group B family of Pak serine/threonine kinases, originally identified as an effector protein for the Rho GTPase Cdc42. Pak4 knockout mice are embryonic lethal and do not survive past embryonic day 11.5. Previous work on Pak4 knockout mice has focused on studying the phenotype of the embryo. Abnormalities in the extraembryonic tissue, however, are common causes of early embryonic death in knockout mice. Extraembryonic tissue associated with the Pak4-null embryos was therefore examined. Abnormalities in both yolk sacs and placentas resulted when Pak4 was deleted. These included a lack of vasculature throughout the extraembryonic tissue, as well as an abnormally formed labyrinthine layer of the placenta. Interestingly, epiblast-specific deletion of Pak4 using a conditional knockout system, did not rescue the embryonic lethality. In fact, it did not even rescue the extraembryonic tissue defects. Our results suggest that the extraembryonic tissue abnormalities are secondary to defects that occur in response to epiblast abnormalities. More detailed analysis suggests that abnormalities in vasculature throughout the extraembryonic tissue and the epiblast may contribute to the death of the Pak4-null embryos. [Copyright &y& Elsevier]