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The aim of this study was to evaluate the influence of vitamin and β-glucan supplementations on growth performance of growing-finishing pigs in Ben Tre province. A total of 36 post-weaned piglets (Duroc x Yorkshire-Landrace) with the initial live weight of 17.42 kg±0.26, was allotted into 3 treatments and 4 replications in a completely randomized design. There were three diets, including basal diet (BD) without any addition of β-glucan or vitamin (diet CT), the BD supplemented with vitamin (diet Vit) and the BD supplemented with β-glucan (diet Glu). The results on growth parameters indicated that final live weight (kg), weight gain (kg), and average daily gain (g/head/day) of pigs in the experimental diets were significantly higher (P

Enhanced carbon capture and oxygen production via water splitting was observed by controlling the plasmon-induced resonance energy transfer (PIRET) for photosystem II (PSII) in thylakoid extracts and spirulina assembled on gold nanoparticle (AuNP) dimer arrays. The two types of vertical (V) and horizontal (H) AuNP dimer arrays were uniformly inserted inside pore diameter-controlled templates. Based on the theoretical calculations, the longitudinal mode of the H AuNP dimer array was found to be sensitive to the nanogap distances between the two AuNPs in resonance with the absorption at P680 of the PSII. The longitudinal modes that interacted with P680 of PSII increased from the V to the H conformer. The optical properties from the H AuNP dimer array caused overlapping absorbance and photoluminescence with PSII, and the H AuNP dimer arrays exhibited a significant increase in carbon capture and oxygen generation rates in comparison with those of the bare PSII protein complex under light irradiation via the controlled PIRET process.

Nanocomposites (NCs) of silver nanoparticles (Ag NPs) and carbon quantum dots (CQDs) have been received increasing attention for diverse applications including sensing, photocatalyst, surface enhanced Raman scattering detection and antibacterial. Herein, we report a unique photosynthesis of Ag NPs-CQD using CQDs as photo-reducing agent. Highly luminescent CQDs were prepared by a hydrothermal method using a mixture of citric acid (CA) and ethylenediamine (EDA) as starting precursors. X-ray diffraction pattern (XRD), transmission electron microscope (TEM), infrared (IR) and Raman spectroscopies confirmed the formation of NCs. We have demonstrated that the formation of Ag NPs accompanied with the degradation of surface fluorophores, which responded for the resolved absorption peak at ca. 346 nm and high luminescence of pristine CQDs. The NCs showed excellent antibacterial affinity to Escherichia coli. The results provide new understandings on the interactions between CQDs and silver ions as well as potential applications of Ag NP – CQD nanocomposites.

The D-band (141 - 178 GHz), due to relatively low attenuation and about 27 GHz available bandwidth, is attractive for point to multipoint backhaul. However, solid state power amplifiers at those frequencies do not have sufficient power to assure a long propagation range with 99.99% availability. This paper will describe the design and fabrication of a novel D-band traveling wave tube power amplifier to enable the first point to multipoint wireless system at D-band. The design approach is for potentially large scale production. For the first time, a new topology of double corrugated waveguide, used as slow wave structure, has been fabricated and measured at D-band. The D-band TWT provides about 35 dB gain and more than 12 W output power.

The folded waveguide (FWG) traveling wave tube (TWT) developed in the frame of the Horizon 2020 TWEETHER project for enabling a novel ${W}$ -band (92–95 GHz) high capacity wireless network for 5G is presented. The FWG TWT was designed by particle-in-cell (PIC) simulations. The technology and the results in terms of measured RF losses and beam transmission from the realized beam tester are presented. Amplification on the first TWT breadboard has been observed but with a poor multireflection pattern resulting from spurious burrs inside the FWG. It indicates, however, that the FWG technology offers great manufacturing simplification compared to conventional helix TWTs, thus enabling a low-cost device with large series production suitable for the wide market of wireless communications.

International audience

We prepared novel Raman substrates for the sensitive detection of submicron-sized plastic spheres in water. Anisotropic nanostar dimer-embedded nanopore substrates were prepared for the efficient identification of submicron-sized plastic spheres by providing internal hot spots of electromagnetic field enhancements at the tips of nanoparticles. Silver-coated gold nanostars (AuNSs@Ag) were inserted into anodized aluminum oxide (AAO) nanopores for enhanced microplastic (MP) detection. We found that surface-enhanced Raman scattering (SERS) substrates of AuNSs@Ag@AAO yielded stronger signals at the same weight percentages for polystyrene MP particles with diameters as small as 0.4 μm, whereas such behaviors could not be observed for larger MPs (diameters of 0.8 μm, 2.3 μm, and 4.8 μm). The detection limit of the submicrometer-sized 0.4 μm in our Raman measurements were estimated to be 0.005% (∼0.05 mg/g =50 ppm) along with a fast detection time of only a few min without any sample pretreatments. Our nano-sized dimensional matching substrates may provide a useful tool for the application of SERS substrates for submicrometer MP pollutants in water.

The European Commission Horizon 2020 TWEETHER project will conclude the activity on September 2018 with the release of one transmission hub and three network terminal equipment for enabling the first W -band, 92–95 GHz, point to multipoint system, for high capacity backhaul and fixed access. The ambition of the project is to develop the European technology for a breakthrough in millimeter wave wireless networks, by introducing the use of traveling wave tubes to achieve the required transmission power for covering, by low-gain antennas, wide area sectors with radius longer than 1 km. The lack of transmission power has so far prevented the use of point to multipoint distribution at millimeter waves. At W -band, the 3 GHz bandwidth provides more than 10 Gbps capacity, and 4 Cbps/km2area capacity for small cells backhaul, with flexible allocation of the base stations and low total cost of operation. The TWEETHER system is also designed to provide high throughput fixed access. This paper will describe the latest results and the technological advancements the project generated, bringing Europe at the state of the art for point to multipoint millimeter wave wireless networks.

The European Commission H2020 TWEETHER project aims to enable the first Point to multipoint wireless backhaul at W-band (92 - 95 GHz) by a transmission hub with a high power Traveling Wave Tube. A 40 W TWT was desigtied and it is in the final fabrication phase to satisfy the system specifications, lhe TWT is designed to reduce the fabrication steps and to provide suitable performance for the wireless network specifications. It is based on a folded waveguide slow wave structure build in copper by high precision CNC milling. The TWT will be enclosed in a case for the transmission hub and connected to a low gain horn antenna. This paper will describe the latest fabrication steps.

An ultra-wideband (UWB) doublet pulse generation technique in the optical domain for UWB-over-fiber systems is presented. Our solution is based on the direct modulation of a semiconductor laser, optical filtering, and chromatic dispersion in a transmission fiber. When the integration of the transmitter in optical access network infrastructure is considered, the transmission length difference, or the difference in accumulated dispersion, is an issue to exactly obtain the desired pulse shape. To solve this problem, we propose to adjust the transmitter operation point, specifically the laser chirp, with respect to the targeted transmission fiber length. Bit error rate measurements prove that doublet pulses can be achieved with fiber length variation from 15 to 40 km of single-mode fiber.

We demonstrate direct modulation of a widely tunable microelectromechanical system (MEMS) vertical-cavity surface-emitting laser (VCSEL). The wavelength tuning is realized with electrothermal actuation of a SiO $_x$ /SiN $_y$ -based MEMS distributed Bragg reflector (DBR). The DBR is deposited in a low-temperature plasma-enhanced chemical vapor deposition chamber on a InP-based half-VCSEL by means of surface micromachining. More than 60 nm of mode-hop free continuous tuning with a center wavelength of 1554 nm is achieved. A maximum 3-dB small-signal modulation response ( $S_{21}$ ) bandwidth of 7.05 GHz is reported. Quasi-error-free operation of a back-to-back link is demonstrated at 10 Gb/s for a record 47-nm tuning range, showing the compatibility of the MEMS tunable VCSEL as a cost-effective optical source in access networks and interconnects.

We present an all-optical computing scheme based on normalization operations of injection-locked lasers. We show cascaded operations in cellular automaton by an all-optical Conway’s Game of Life and simulate 100 generations of gaming.

Today, even in access networks, data traffic is enormously increasing, a trend that causes existing passive optical network (PON) infrastructures to become bottlenecks in a tele- and data-communication infrastructure, which is aimed to be both broadband and seamless. Thus, two major objectives are considered for next-generation PONs (NG-PONs), i.e., first, bandwidth increase, and second, reach extension to reduce deployment costs. Here, we describe a new reach extension scheme that at the same time allows increasing the number of subscribers in the network. The amplification technique is based on a bidirectional semiconductor optical amplifier (SOA). It is shown that the extender configuration not only meets the bandwidth and budget requirements for NG-PONs but also remarkably improves them. Differential (quadrature) phase-shift keying (D(Q)PSK) signals are investigated in this paper. Hybrid wavelength-division multiplexing/time-division multiplexing (WDM/TDM) transmission up to 120-Gb/s downstream and 40-Gb/s upstream are experimentally demonstrated. The access budget of 33.4 dB is achieved at 10 Gb/s on every WDM channel in case of DPSK enabling a splitting ratio of 1:512 per wavelength. Furthermore, optical power budget of 40 dB is obtained when DQPSK is used, where a splitting ratio of 1024 per wavelength can be supported. Additionally, a cost-efficient chirped managed directly modulated laser scheme is proposed for DPSK signal generation in U.S. scenario enabling a high-power budget performance low-cost transmitter configuration, which appears suitable for NG-PON application. The proposed technique also alleviates nonlinear impairments [specifically, cross-phase modulation (XPM)], which appear in dense WDM transmission.

Photoluminescence (PL) is the center property to deploy carbon quantum dots (CQDs) in diverse applications although their physicochemical origin is still debated. Herein, carboxylic-terminated CQDs were synthesized from citric acid (CA) and treated sequentially with ethylenediamine (EDA). Infrared, magnetic, X-ray photoelectron and UV–Vis spectroscopies indicated the formation of surface fluorophores by the EDA treatment. The post-decorated surface fluorophores accounted for a resolved UV absorption band at 346 nm, which originated from HOMO → LUMO transition in the fluorophores. The post-decorated fluorophores dominated the emission spectrum of CQDs when excited with wavelengths below 340 nm and enhanced the PL quantum yield of CQDs from 20.7% to 47.6%. The results pave new understanding on the optical properties of CQDs derived from CA and amines.

International audience

The objective of this study was to optimize and compare production condition of GBRto maximize bio-active compounds. In order to do that the white sticky rice (CLN) and black sticky rice (DH6) varieties from An Giang Province, Mekong Delta, Viet Nam were selected for this study because of their popularity and benefits. Optimum conditions for dehusk, steep and germination to maximize γ-amino butyric acid, ferulic acid and γ-oryzanol content in brown rice were determined. Both sticky sticky varieties were dehusked at various grain’s humidity conditions which were 12, 13, 14, 15, 16 and 17%. The brown rice was soaked in various solutions which were pH 2, 3, 4, 5 , 6, 7 and distilled water at room temperature for 6 hours and germinated in various CO2 concentration as 0, 3, 5, 7, 9% at 37oC for 16, 20, 24, 28 and 32 hours. The results indicated that the optimum condition for dehusk depended on grain’s moisture content which was from 13 to 14% for black sticky and from 12 to 14% for white sticky. The highest γ-amino butyric acid content was obtained when the rice was soaked in solution at pH 5 and germinated in 5% CO2 32 hours for white sticky rice and 7% CO2 32 hours for black sticky rice respectively. The γ-amino butyric acid content in white sticky rice and black sticky rice increased as 7.5 and 9.13 times when compared to brown rice. The content of ferulic acid and γ-oryzanol in GBRwere also increased after germination. Black sticky rice showed better for value for production of germinated brown rice. &nbsp

We propose and experimentally demonstrate a flexible wavelength division multiplexing/time division multiplexing network architecture for converged metro-access environment. Entire passiveness in the fiber plant is achieved with remote amplification in the signal distribution nodes along the metro ring and in the power splitters of the local access tree. We assist a traditional remote pumping scheme with a distributed pump provided by the optical network units and demonstrate that loss budgets beyond 30 dB can be supported. Data transmission of up to 10 Gb/s is evaluated in different deployment scenarios, reaching from a 78 km long reach rural to a dense 1:128 split/ urban configuration with field installed fibers, including also worst case resilience configurations.

This paper gives an overview of recent demonstrations of optical 2R regeneration achieved by vertical microcavity mirror-based multiple-quantum-well saturable absorber (SA). The potential of the device to perform wavelength division multiplexing regeneration is first demonstrated through the first pigtailed SA chip implemented with eight independent fibers using a cost effective coupling technique. The cascadability and wavelength tunability assessment of this module associated with a power limiter fiber-based function has been experimentally demonstrated at 42.6 Gbit/s. Because this method of power limiting is not a suitable solution for all-optical multichannel 2R regeneration, a new SA structure allowing a power limiting function was proposed. We describe and characterize such a structure in this paper. This new SA opens the door to a complete passive all-optical 2R regeneration relying upon a single technology, as shown in this paper through the use of two SA: SA.0 for extinction ratio enhancement and SA.1 for high-power level equalization allowing receiver sensitivity (up to 3.5 dB) and Q-factor (up to 1.4 dB) improvement for a RZ signal at 42.6 Gbit/s. The limitation of SA.1 when the regenerator must be cascaded a large number of times is also described, leading to the observation that SA.1 should be more suitable for phase encoded formats that are more spectrally efficient than ON-OFF keying formats. A SA.1 used as a phase-preserving amplitude regenerator in a 42.6 Gbit/s RZ differential quadrature phase-shift keying transmission system is, therefore, assessed . A fiber launched power margin of 2 dB and a receiver sensitivity improvement of 5.5 dB are obtained. Finally, we use, for the first time an SA.1 as a phase-preserving amplitude regenerator of RZ differential quadrature phase-shift keying signals. The regenerator is assessed in a recirculating loop at 28 Gbaud. The system tolerance to nonlinear phase noise is enhanced by 3 dB and the distance improvement factor was 1.3 for a bit error rate = 10-4.

The present paper describes different methods for storing the benzotriazole (BTA) corrosion inhibitor in the titanium dioxide nanotubes (TNT) as nanocontainers. Three methods were used, including the vacuum impregnation at ambient temperature, the vacuum impregnation at cooling temperature () and the rotary vacuum evaporation. TNT, BTA and BTA/TNT products were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) surface area, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopy. nanotube powder was synthesized by hydrothermal treatment from the inexpensive spherical commercial precursor. The results obtained from SEM, TEM images and BET values showed the successful synthesis of TNT with a homogeneous morphology of nano size tubes and a large specific surface . The existence of BTA in TNT was demonstrated. The BTA/TNT obtained via the rotary vacuum evaporation contained a very significant amount of BTA (66.6 weight %) but BTA existed mostly outside the nanotubes. Two processes of vacuum impregnation at ambient temperature and vacuum impregnation at cooling temperature revealed that there was about 8 weight % BTA stored in BTA/TNT product and BTA was present mostly inside the nanotubes.

A new, simple, and cost efficient method is experimentally demonstrated to generate 6th order Gaussian derivative optically. Proposed technique is based on directly modulated semiconductor laser, optical filtering and chromatic dispersion of fiber transmission line.

Optical UWB pulse generation and wireless propagation through antenna is investigated. Experimental BER results are presented. It is shown due to antenna characteristics monocycle pulse is converted into 3rd-order Gaussian derivative after wireless propagation.

A new method to generate ultra-wideband (UWB) pulses based on direct modulation of laser and optical filtering is demonstrated. The intensity modulation and the frequency modulation of the directly modulated laser are combined by the optical filter, which performs a photonic electro-optical derivative operation. Gaussian driving pulses are used in order to generate monocycles for ultra-wideband systems. In association with laser power oscillation, doublet waveforms could also be obtained. Monocycle and doublet pulses are experimentally generated with fractional bandwidths of 139 and 105%, respectively.

This paper proposes a budget extender which is at the same time burst power equalizer based on SOAs for upstream 10 Gbit/s PON that achieves 38 dB access budget and 16 dB dynamic range compression.

A multi-layer next generation PON prototype has been built and tested, to show the feasibility of extended hybrid DWDM/TDM-XGPON FTTH networks with resilient optically-integrated ring-trees architecture, supporting broadband multimedia services. It constitutes a transparent common platform for the coexistence of multiple operators sharing the optical infrastructure of the central metro ring, passively combining the access and the metropolitan network sections. It features 32 wavelength connections at 10 Gbps, up to 1000 users distributed in 16 independent resilient sub-PONs over 100 km. This paper summarizes the network operation, demonstration and field trial results. (C) 2014 Elsevier Inc. All rights reserved.

The integration of ultra-wideband (UWB)-over- ber into passive optical network (PON) is of great interest as it bene ts the high bandwidth capability from optical network technologies and the high exibility from wireless network technologies. The later can only be done with a reasonable cost when a universal optical transmitter, which is capable of generation both UWB and PON signals, is available. Direct modulation of semiconductor laser was demonstrated to be suitable for high bit-rate PON systems, however the generation of UWB signals by this technique is still challenging. Using the chirp properties of directly modulated semiconductor lasers, UWB signals are generated. Di erent UWB signal waveforms and polarities are obtained. The received electrical spectra conform to the requirements of indoor UWB systems.