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Purpose: To study the curative effect of the volatile oil from Litsea cubeba (EOL) on type II collagen (CII) induced arthritic (CIA) rat. Methods: The chemical constituents of EOL were analyzed by gas chromatography-mass spectrometry (GC-MS). The analgesic effect of the oil was assessed by acetic acid-stimulated torsion and hot plate methods, while antiinflammatory potential was further assessed by in an ear oedema model induced by dimethylbenzene in mice. The anti-rheumatoid arthritis (RA) activity of EOL in mice was evaluated in terms of paw volume, arthritis index, thymus and spleen index, and serum inflammatory factor levels. Results: GC-MS showed that α-citral (26.42 %), β-citral (21.94 %), and limonene (12.79 %) were the main components of EOL. Different doses of EOL (50, 100, 200 mg/kg) exerted varying inhibitory effects on torsion in mice induced by acetic acid (p < 0.01) but had no significant effect on thermal stimulation-induced pain. EOL reduced ear oedema in mice (p < 0.01). In addition, EOL (50, 100, 200 mg/kg) reduced the mouse paw volume, arthritis index, and thymus and spleen index (p < 0.01). Furthermore, EOL reduced proinflammatory cytokines in serum but increased antiinflammatory cytokines (p < 0.01). Conclusion: EOL ameliorates symptoms of inflammation in CIA rats by inhibiting inflammatory reactions, suggesting it could be further developed as an anti-arthritic drug. Keywords: Litsea cubeba, Essential oil, Rrheumatoid arthritis, Pro-inflammatory cytokines

Enteric diseases caused by

FigS1-Site-directed mutation of the ��-galactosidase from Streptococcus thermophilus for functional yogurt making(supporting document), FigS1-supporting document

Tables2-Site-directed mutation of the ��-galactosidase from Streptococcus thermophilus for functional yogurt making(supporting document, Tables2-supporting document

TableS1-Site-directed mutation of the ��-galactosidase from Streptococcus thermophilus for functional yogurt making, TableS1-supporting document

Sequence of bgaQ

Enterococcus avium (E. avium) is a common bacterium inhabiting the intestines of humans and other animals. Most strains of this species can produce gamma-aminobutyric acid (GABA) via the glutamate decarboxylase (GAD) system, but the presence and genetic organization of their GAD systems are poorly characterized. In this study, our bioinformatics analyses showed that the GAD system in E. avium strains was generally encoded by three gadB genes (gadB1, gadB2, and gadB3), together with an antiporter gene (gadC) and regulator gene (gadR), and these genes are organized in a cluster. This finding contrasts with that for other lactic acid bacteria. E. avium SDMCC050406, a GABA producer isolated from human feces, was employed to investigate the contribution of the three gadB genes to GABA biosynthesis. The results showed that the relative expression level of gadB3 was higher than those of gadB1 and gadB2 in the exponential growth and stationary phases, and this was accompanied by the synchronous transcription of gadC. After heterologous expression of the three gadB genes in Escherichia coli BL21 (DE3), the Km value of the purified GAD3 was 4.26 ± 0.48 mM, a value lower than those of the purified GAD1 and GAD2. Moreover, gadB3 gene inactivation caused decreased GABA production, accompanied by a reduction in resistance to acid stress. These results indicated that gadB3 plays a crucial role in GABA biosynthesis and this property endowed the strain with acid tolerance. Our findings provided insights into how E. avium strains survive the acidic environments of fermented foods and throughout transit through the stomach and gut while maintaining cell viability.

International audience; For the first time, we show that the density of nanostructures on Black Silicon obtained by wafer-level cryogenic plasma processing increases with a high level of doping, extending the spectral range of its very high absorptivity from near-infrared to far-infrared. We have found experimentally and confirmed by simulations that, for highly doped Black Silicon, a high absorptivity is observed till 15 µm. Subsequent processing of SEM images reveals that these noteworthy radiative properties are probably due to particular morphological features of heavily doped Black Silicon at the nano-scale. These features are quantified through statistical image processing. Reported results pave the way to highly integrated and effective infrared sources using Black Silicon.

Dynamic structural color has attracted considerable attentions due to its good tunable characteristics. Here, an ultrathin asymmetric Fabry-Perot (FP)-type structural color with phase-change material VO2 cavity is proposed. The color-switching performance can be realized by temperature regulation due to the reversible monoclinic-rutile phase transition of VO2. The various, vivid structural color can be generated by simply changing the thickness of VO2 and Ag layers. Moreover, the simple structural configuration enables a large-scale, low-cost preparation on both rigid and flexible substrates. Accordingly, a flexible dynamic structural color membrane is adhered on a cup with a curved surface to be used for temperature perception. The proposed dynamic structural color has potential applications in anti-counterfeiting, temperature perception, camouflage coatings among other flexible optoelectronic devices.

Structural color with polarization sensitivity has been widely studied due to its benefits for improving information storage and dynamic color display capacity. However, large amount and good concealment of information encoding are the major issues to be addressed. Here, we propose the elliptical Al/a-Si/Al (metal-insulator-metal, MIM) nanostructure arrays as the basic building blocks to realize polarization-sensitive subtractive structural colors for information encoding, and dynamic polarization-resolved displays. The experimentally realized structural color exhibits a wide color gamut covering the whole cyan, magenta, and yellow (CMY) color system, and presents a strong dependence on the incident polarization state due to its shape anisotropy. A new approach to improve the information encoding capacity is demonstrated using this structure combined with the polarization-independent nanostructures, increasing the concealment of information. Additionally, the polarization controllable dynamic display is engineered by the well-designed pixels with respect to different polarizations, generating the animation effect. These intrinsic properties and functionalities of the proposed structural color significantly extend its potential to the fields of information encoding, security encryption, and dynamic displays, not limited to color printing and filtering devices.

A flexible broadband absorber based on an all-dielectric multilayer structure is proposed to get an average absorbance of 97.4%, covering the whole visible light. Additionally, such high absorption presents an extraordinary angular tolerance of up to ± 50 ∘ . Due to the single broadband resonance in the highly lossy Fabry–Perot (F–P) cavity and the intrinsic loss property of Ge, the proposed multilayer structure achieves the broadband absorption effect. Furthermore, the simple all-dielectric multilayer configuration requires no noble metal, making the lithography-free, large-scale, cost-effective manufacturing process feasible. Meanwhile, the good substrate adaptation facilitates its preparation on a flexible substrate. Accordingly, a three-dimensional object covered by the proposed flexible absorber can be treated as a two-dimensional black hole, revealing the effect of stealth. The proposed perfect absorber shows potentials for camouflage coating, solar energy collection, flexible optoelectronics, and other fields.

A broadband optical absorber based on the nanostructured germanium (Ge) film composed of single-sized circular nanodisk-nanohole arrays is proposed, which demonstrates high efficiency, strong polarization independence, and large viewing angle. Due to the electric and magnetic resonance absorption modes excited by the nanostructure arrays in highly lossy Ge film, the absorber obtains a high absorptivity, reaching above 90% over the full visible wavelength, and it can be maintained well at a large viewing angle over ±50°. Based on the geometrical symmetry, the absorber is proved to be polarization independent. Moreover, the simple single-sized nanostructure within a certain size tolerance decreases the design and fabrication complexity. The structural configuration with a slight Ge sidewall formed in the nanofabrication process could enhance the overall light absorption. These results indicate that the proposed broadband absorber has great potential in various applications such as anti-reflective coating and perfect cloaking.

International audience; We present the Near-Infra-Red (NIR) and Mid-Infrared (MIR) absorption properties of Ultra-Black Silicon obtained by wafer-level cryogenic plasma processing. We found that when using highly-doped silicon, the spectral range of near-unity full absorption of light is extended from the visible range till a wavelength of 10 µm. This MIR wavelength range coincides with that of the maximum of black-body radiation from room temperature up to a few thousand Kelvin. Therefore, according to Kirchhoff's Law, we take advantage of the enhanced properties of black silicon to realize ultra-compact light-sources of high efficiency, which are operated in combination with a MEMS-FTIR spectrometer.

Structural color printing based on plasmonic metasurfaces has been recognized as a promising alternative to the conventional dye colorants, though the color brightness and polarization tolerance are still a great challenge for practical applications. In this work, we report a novel plasmonic metasurface for subtractive color printing employing the ultrathin hexagonal nanodisk-nanohole hybrid structure arrays. Through both the experimental and numerical investigations, the subtractive color thus generated taking advantages of extraordinary low transmission (ELT) exhibits high brightness, polarization independence and wide color tunability by varying key geometrical parameters. In addition, other regular patterns including square, pentagonal and circular shapes are also surveyed, and reveal a high color brightness, wide gamut and polarization independence as well. These results indicate that the demonstrated plasmonic metasurface has various potential applications in high-definition displays, high-density optical data storage, imaging and filtering technologies.

This study investigated thermophilic bioleaching of a low grade nickel-copper sulfide using mixture of four acidophilic thermophiles. Effects of 0.2g/L l-cysteine on the bioleaching process were further evaluated. It aimed at offering new alternatives for enhancing metal recoveries from nickel-copper sulfide. Results showed a recovery of 80.4% nickel and 68.2% copper in 16-day bioleaching without l-cysteine; while 83.7% nickel and 81.4% copper were recovered in the presence of l-cysteine. Moreover, nickel recovery was always higher than copper recovery. l-Cysteine was found contributing to lower pH value, faster microbial growth, higher Oxidation-Reduction Potential (ORP), higher zeta potential and absorbing on the sulfide surfaces through amino, carboxyl and sulfhydryl groups. X-ray Diffraction (XRD) patterns of leached residues showed generation of S, jarosite and ammoniojarosite. Denaturing Gradient Gel Electrophoresis (DGGE) results revealed that l-cysteine could have variant impacts on different microorganisms and changed the microbial community composition dramatically during nickel-copper sulfide bioleaching.

A ferroelectric liquid crystal (FLC) cell with continuously alignment structure is realized by a polarization hologram method for fabricating a Pancharatnam-Berry (PB) lens, which is employed as a concave/convex lens. The PB phase can be maintained by the optical axis in-plane switching; meanwhile, its diffraction efficiency can be tuned in a certain range by electrically controlling azimuthal angle and optical biaxiality of the smectic helical structure realized by deformed helix ferroelectric liquid crystals. The measured diffraction efficiency of the fabricated device is up to 87% and the response time can be 300μs with a low electric voltage. The FLC PB lens can have potential applications in existing optical devices and the realization of FLC with continuous alignment structure can be further used for other LC-based optical devices.

The effect of L-cysteine in different concentrations on the bioleaching of Ni-Cu sulfide was studied with an extremely thermophilic archaea, Acidianus manzaensis. It is found that adding certain amounts of L-cysteine to the bioleaching system of Ni-Cu sulfide largely enhances the leaching rate. X-ray diffraction (XRD) patterns show the change of bioleached solid residues and the effect of L-cysteine on the surface charges of minerals. Zeta potential and IR spectra of mineral surface show that the interaction between L-cysteine and mineral leads to the formation of metal complex, which is propitious to the bioleaching of Ni-Cu sulfide by Acidianus manzaensis.

The microbial ecology of the bioleaching of Ni-Cu sulfide is poorly understood and little effort has been made to handle the microbiological components of these processes. In this study, denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA genes fragments from bacteria was used to evaluate the changes of the bacterial community in the process of Ni-Cu sulfide bioleaching in a shaken flask system. The results revealed that the bacterial community was disturbed after the addition of Ni-Cu sulfide. Phylogenetic analyses of 16S rRNA fragments revealed that the retrieved sequences clustered together with the genera Acidithiobacillus and Leptospirillum. Multidimensional scaling (MDS) and cluster analysis of DGGE-banding patterns revealed that the process of Ni-Cu sulfide bioleaching in 46days was divided into three stages. During the bioleaching process of Ni-Cu sulfide, Leptospirillum was always dominant. The genera Acidithiobacillus was only detected at early and later stages of the bioleaching process. These results extend our knowledge on microbial dynamics in Ni-Cu sulfide bioleaching, a key issue required to improve commercial applications.

The microbial ecology of the bioleaching of chalcopyrite ores is poorly understood and little effort has been made to handle the microbiological components of these processes. In this study, the composition and structure of microbial communities in acid mineral bioleaching systems have been studied using a PCR-based cloning approach. Denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA gene fragments from bacteria was used to evaluate the changes in the bacterial community in the process of chalcopyrite bioleaching in a shaken flask system. The results revealed that the bacterial community was disturbed after the addition of chalcopyrite. Phylogenetic analyses of 16S rRNA gene fragments revealed that the retrieved sequences clustered together with the genera Acidithiobacillus, Leptospirillum, and Acidovorax. Multidimensional scaling analysis of DGGE banding patterns revealed that the process of chalcopyrite bioleaching in 46 days was divided into four stages. In the first stage, Leptospirillum were dominant. In the second stage, Leptospirillum and Acidithiobacillus groups were mainly detected. In the third and fourth stages, the bacterial community was relatively stable and was dominated by Leptospirillum and Acidithiobacillus. These results extend our knowledge on the microbial dynamics in chalcopyrite bioleaching, a key issue required to improve commercial applications.