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esearch and practice during the last 20 years has shown that urban agriculture can contribute to minimising the effects of climate change by, at the same time, improving quality of life in urban areas. In order to do so most effectively, land use and spatial planning are crucial so as to obtain and maintain a supportive green infrastructure and to secure citizens' healthy living conditions. As people today trend more towards living in green and sustainable city centres that can offer fresh and locally produced food, cities become again places for growing food. The scope of urban agriculture thereby is to establish food production sites within the city's sphere; for example, through building-integrated agriculture including concepts such as aquaponics, indoor agriculture, vertical farming, rooftop production, edible walls, as well as through urban farms, edible landscapes, school gardens and community gardens. Embedded in changing urban food systems, the contribution of urban agriculture to creating sustainable and climate-friendly cities is pivotal as it has the capacity to integrate other resource streams such as water, waste and energy. This article describes some of the current aspects of the circular city debate where urban agriculture is pushing forward the development of material and resource cycling in cities. European Cooperation in Science and Technology (COST): CA17133; EU Horizon 2020 Programme info:eu-repo/semantics/publishedVersion

The use of hydrogenated titanium powders combined with traditional PM techniques may lead to a significant reduction in the manufacturing costs of titanium components. In this work, the advantages and limitations of the use of TiH2 powder consolidated through the conventional press-and-sinter method were investigated. Processing parameters related to the compaction and sintering were studied for a TiH2 powder in the particle sizes

International audience; This paper presents first results of SPIS-DUST modelling of the interaction between the lunar plasma environment , regolith and a lander. The model takes into account the geometry of the Luna-Glob lander, the electric properties of materials used on the lander surface, as well as Luna-Glob landing place. Initial conditions were chosen based on the current theoretical models of formation of dusty plasma exosphere and levitating charged dust particles.

International audience; One of the complicating factors of the future robotic and human lunar landing missions is the influence of the dust. The absence of an atmosphere on the Moon's surface is leading to the compaction and sintering of the dust particles found on the Moon surface. Properties of regolith as well as near-surface lunar exosphere depend on many factors, including the solar activity, lunar local time, position of the Moon relative to the Earth's magnetotail. The upper insulating regolith layer is electrically charging by photoelectron emission due to solar UV radiation and solar wind particles. Positive charge is created on the lunar illuminated side, while its night side is negatively charged. Charge distribution, and thus surface potential, depend on the lunar local time, latitude and the electrical properties of the regolith (the presence of water in the upper layer of the regolith, for example, might change the regolith electric conductivity). Understanding of mechanisms of the dust electric charging, dust levitation and Lander electric charging is essential for interpretation of measurements of two instruments: Dust Impact sensor and Langmuir Probe included in the forthcoming Luna-Glob lander mission what is under development now according to the Russian space program. One of the tools, which allows to simulate the dust emission from the Moon and asteroids, its transport, deposition and its interaction with a lander, is the SPIS-DUST (Spacecraft Plasma Interaction Software) code [1]. This paper presents first results of SPIS-DUST modelling of the interaction between the lunar exosphere, regolith and a lander. The model takes into account the geometry of the Luna-Glob lander, the electric properties of materials used on the lander surface, as well as Luna-Glob landing place. Initial conditions were chosen based on the current theoretical models of formation of dusty plasma exosphere and levitating charged dust particles. This paper is the first step in the cooperation between IKI, ESA, ONERA and LATMOS in frame of the Luna-Glob project on simulation of the lunar dusty plasma environment.

The use of hydride powders in titanium powder metallurgy (P/M) is a low cost alternative for the manufacture of titanium alloys. However, due to the high reactivity of these powders, parts produced using this technique may contain interstitial impurities such as oxygen, nitrogen and carbon. In this work a factorial design approach was used to evaluate the influence of some stages of P/M upon the levels of these elements in sintered samples of Ti-6Al-4V. Milling time of titanium hydride powders, sintering temperature and holding time were evaluated. The effect of milling time was detected as the most significant for the increase in oxygen levels. The contents of all elements were affected by the increase of sintering temperature from 1200 °C to 1400 °C. Holding time was shown to be significant only for the carbon absorption in the samples sintered at 1400 °C.

The titanium alloys are used for applications that demand high performance, including surgical implants and aerospace applications. Powder metallurgy is an advantageous alternative for titanium parts production with complex geometries at a relative low cost. Despite that, it is verified that the introduction of interstitial elements (oxygen, nitrogen and carbon) wile processing these alloys, though can increase hardness and mechanical resistance, which is frequently related to the reduction of ductility and fragility increase. The objective of this work is to investigate the influence of the interstitial elements in commercially pure Ti and Ti-13Nb-13Zr alloy produced by powder metallurgy (P/M). Samples were produced by the mixing of hydrided metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering at 1400 °C, in vacuum. Sintered samples were characterized for phase composition, microstructure and microhardness by X-ray diffraction, scanning electron microscopy and Vickers indentation, respectively. The interstitial content was analyzed by Leco equipment. It was shown that the samples were sintered to high densities with a Widmanstatten microstructure. The oxygen and nitrogen contents are above the ELI (Extra Low Interstitial) and the critical issues were identified in the original blended elemental route.

The Ti–13Nb–13Zr near-β alloy was developed aiming the replacement of the traditional Ti–6Al–4V alloy in surgical implants owing to its larger biocompatibility. Samples of this alloy were obtained using the blended elemental technique from hydrided powders. The isochronal sintering of the compacts for 2 h was carried out in the range 900–1,400 °C with a heating rate of 20 °C min−1. In this work, the behavior of the elementary powders during sintering and the corresponding microstructural evolution were investigated. The alloy was characterized by means of scanning electron microscopy (SEM) in the backscattered mode, X-ray diffraction, and density measurements. The results indicate that the homogenization of the alloy is diffusion-controlled. With increasing temperature, homogenization of the alloy takes place and a fine plate-like α + β structure is found throughout the microstructure in temperatures above 1,300 °C. The process variables were defined aiming to minimize interstitial pick-up (C, O, and N) and avoiding intensive grain growth.

Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders1, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach2 to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing3,4,5,6,7,8,9,10,11 and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders.

International audience; This paper presents a numerical estimation of spacecraft surface charging that combines the effects of both spacecraft material properties and severe environments, often called worst-cases. A series of simulations with the SPIS-GEO tool (Spacecraft Plasma Interaction Software) is analysed in order to determine if a worst-case environment can be extracted from the literature. The simulation especially focuses on the conductivity parameters, especially radiation induced. It is found hardly feasible to define a single and global worst-case, applicable to all situations.

We report design, fabrication, and test of a monolithic GaAs optoelectronic integrated circuit (OEIC) implementing a broad-band optically driven digital/analog radio frequency (RF) interface. The integrated circuit (IC) was fabricated using a foundry-compatible enhancement/depletion metal-semiconductor field-effect transistor (MESFET) process with no added lithography steps. A single optical fiber carries externally amplitude modulated 0.85-/spl mu/m light to the on-chip GaAs metal-semiconductor-metal interdigitated photodetector. RF as well as simultaneous digital information encoded at up to 10 Mb/s using a novel waveform set is transmitted over the fiber. The serial digital data is self-clocked into on-chip registers to control the RF signal chain, which includes a three-bit digital attenuator. The circuit operates in an asynchronous mode to detect digital and RF on the single optical-fiber input, control RF level, and transmit the 2-8-GHz RF to the IC's electrical output. Measurements characterizing the RF and digital performance of the IC as well as a demonstration of the full optoelectronic mixed-mode functioning of the IC are presented.

O estudo teve como objetivo identificar e comparar os resultados de glicemia de pacientes adultos com diabetes tipo 2 por meio de duas técnicas, laboratorial e capilar. Estudo comparativo foi desenvolvido no período de setembro a dezembro de 2007. A população foi constituída de 36 pacientes adultos residentes no município de Planaltina do Paraná, PR. A pesquisa foi realizada no laboratório de análises clínicas municipal. Para o exame laboratorial foi usado o sangue venoso e para o teste capilar o sangue da ponta do dedo. A maioria dos pacientes (63,9%) era do gênero feminino, idade média de 62,4 anos. Quanto à escolaridade, 41,6% dos pacientes possuíam menos de 8 anos de estudo. Em relação aos níveis glicêmicos, o p-valor do teste Kappa foi significativo em todas as categorias (p< 0,001, p=0,005 e p=0,001), mostrando concordância. Os dados indicam elevada precisão e acurácia dos resultados de glicemia obtidos por meio do glicosímetro, quando comparada ao teste padrão obtido em laboratório. Palavras-chave: Diabetes mellitus tipo 2. Glicemia capilar. Glicemia laboratorial.

This paper presents the design of a MESH network to provide services simultaneous of voice, video and data. The network architecture is constituted by two access points(APpsilas), two mobile wireless routers (WRpsilas), a mobile unit, a portable unit and a control center. The network was implemented at Instituto Politecnico Nacional (IPN), campus Zacatenco. We make different communications tests of voice, data and video with and without the network infrastructure to carry out a system evaluation. We also tested the network with different speeds reaching up to 100 km/h.

A Ka-band HBT two-stage LNA has been developed. This circuit is to be used in a multifunction T/R module which includes both analog and digital functions. The measured noise figure is 5 dB from 30 GHz to 34 GHz, with an associated gain of better than 7.5 dB. A single-stage LNA has also been developed. The measured noise figure is 4 dB from 33 GHz to 35 GHz with an associated gain of 4 dB. These results are the best yet reported at Ka-band for a HBT LNA. The amplifiers have been designed to minimize the noise measure.

Gallium arsenide double-drift Read IMPATT diodes are under development for use at 40 GHz. Such diodes have offered higher efficiency and average power than silicon diodes. The advantage may be ascribed to both the intrinsic properties of GaAs and the more complex doping structures used. In this paper, we describe diodes which give 16 W peak power at efficiencies up to 15%. Duty cycles between 5% and 30% have been employed at various peak power levels. The techniques used to design the double Read doping profiles and their resulting microwave properties are discussed. The characteristics of the Kurokawa test circuit are described in terms of measured S-parameters.

Rare-earth (R) phosphate glasses have shown great promise in the laser and optoelectronics industry. Their structure plays an important role in their physical characteristics, with the R...R closest approach affecting their optical and magnetic properties. A novel characterisation method for amorphous materials which makes use of magnetic field effects has enabled the first direct experimental evidence of nearest neighbour R...R separation in these materials.

Excellent noise (0.41 dB minimum noise figure with 11.5 dB associated gain at 18 GHz) and linearity (third order intercept point of 37.6 dBm at 42.5 mW DC power giving a linearity figure of merit (LFOM) of 137) have been obtained for InAlAs-InGaAs metamorphic HEMTs on a GaAs substrate. These devices have been used to design and fabricate microwave and millimeter wave amplifiers. Amplifier results are presented.

The authors describe the design, fabrication, and performance of a 4-18 GHz matrix distributed amplifier which incorporates a novel biasing scheme enabling the amplifier to run at higher voltages while drawing only half of the current of conventional multistage amplifiers having comparable gain levels. A voltage divider is used at the input of the FET pair to derive the gate bias, ensuring that both FETs are biased at the same point. This scheme enables the stages to be connected in cascade at RF frequencies and in cascode for DC biasing, thus conserving current. The amplifier shows >13 dB gain across the frequency band using a chip area of only 1.9 mm*2.1 mm. >