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Abstract Solid organ transplant (SOT) recipients are especially at risk of developing infections by multidrug resistant (MDR) Gram-negative bacilli (GNB), as they are frequently exposed to antibiotics and the healthcare setting, a...
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Abstract Solid organ transplant (SOT) recipients are especially at risk of developing infections by multidrug resistant (MDR) Gram-negative bacilli (GNB), as they are frequently exposed to antibiotics and the healthcare setting, and are regulary subject to invasive procedures. Nevertheless, no recommendations concerning prevention and treatment are available. A panel of experts revised the available evidence; this document summarizes their recommendations: (1) it is important to characterize the isolate's phenotypic and genotypic resistance profile; (2) overall, donor colonization should not constitute a contraindication to transplantation, although active infected kidney and lung grafts should be avoided; (3) recipient colonization is associated with an increased risk of infection, but is not a contraindication to transplantation; (4) different surgical prophylaxis regimens are not recommended for patients colonized with carbapenem-resistant GNB; (5) timely detection of carriers, contact isolation precautions, hand hygiene compliance and antibiotic control policies are important preventive measures; (6) there is not sufficient data to recommend intestinal decolonization; (7) colonized lung transplant recipients could benefit from prophylactic inhaled antibiotics, specially for Pseudomonas aeruginosa ; (8) colonized SOT recipients should receive an empirical treatment which includes active antibiotics, and directed therapy should be adjusted according to susceptibility study results and the severity of the infection.
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We demonstrate compact tunable phased-array wavelength-division multiplexers driven by surface acoustic waves (SAWs) in the low GHz range. The devices comprise two couplers, which respectively split and combine the optical signal,...
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We demonstrate compact tunable phased-array wavelength-division multiplexers driven by surface acoustic waves (SAWs) in the low GHz range. The devices comprise two couplers, which respectively split and combine the optical signal, linked by an array of single-mode waveguides (WGs). Two different layouts are presented, in which multi-mode interference couplers or free propagating regions were separately employed as couplers. The multiplexers operate on five equally distributed wavelength channels, with a spectral separation of 2 nm. A standing SAW modulates the refractive index of the arrayed WGs. Each wavelength component periodically switches paths between the output channel previously asigned by the design and the adjacent channels, at a fixed applied acoustic power. The devices were monolithically fabricated on (Al,Ga)As. A good agreement between theory and experiment is achieved.
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The objective of this work was to study the effect of shading screens, normally used during the day for cooling purposes, on the night-time climate of unheated greenhouses. For this purpose, first a number of experimental measurem...
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The objective of this work was to study the effect of shading screens, normally used during the day for cooling purposes, on the night-time climate of unheated greenhouses. For this purpose, first a number of experimental measurements were taken during cold nights to characterise the greenhouse climate both with and without an aluminised external screen. Secondly a Computational Fluid Dynamic (CFD) model of greenhouse was developed. After validation of the model by comparison with experimental data, the model was used to simulate the greenhouse climate for different sky conditions ranging from cloudless to overcast nights. Simulations were performed for a greenhouse with internal and external shading screens and for the same greenhouse without screens. Experimental results showed the positive effect of an external shading screen, whose use increased night-time temperature and reduced the risk of thermal inversion. Its effect was much stronger under clear sky conditions. The CFD model supported this conclusion and provided a detailed explanation of the temperature behaviour of all the greenhouse types considered. CFD simulations proved that an aluminised screen placed inside the greenhouse at gutter height gave the greatest thermal increase. Therefore, external or internal screens can help to increase the sustainability of greenhouse production in areas with mild winter climates by enhancing the use of solar energy stored in the greenhouse soil during the previous day and released at night-time.
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In the context of Long-Term Evolution (LTE), the next generation mobile telecommunication network, femtocells are low-power base stations that efficiently provide coverage and capacity indoors. This paper presents a computationall...
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In the context of Long-Term Evolution (LTE), the next generation mobile telecommunication network, femtocells are low-power base stations that efficiently provide coverage and capacity indoors. This paper presents a computationally efficient dynamic system-level LTE simulator for enterprise femtocell scenarios. The simulator includes specific mobility and traffic and propagation models for indoor environments. A physical layer abstraction is performed to predict link-layer performance with low computational cost. At link layer, two important functions are included to increase network capacity: Link Adaptation and Dynamic Scheduling. At network layer, other Radio Resource Management functionalities, such as Admission Control and Mobility Management, are also included. The resulting tool can be used to test and validate optimization algorithms in the context of Self-Organizing Networks (SON).
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We develop, to the best of our knowledge, the first model for an array waveguide grating (AWG) device subject to quantum inputs and analyze its basic transformation functionalities for single-photon states. A commercial, cyclic AW...
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We develop, to the best of our knowledge, the first model for an array waveguide grating (AWG) device subject to quantum inputs and analyze its basic transformation functionalities for single-photon states. A commercial, cyclic AWG is experimentally characterized with weak input coherent states as a means of exploring its behaviour under realistic quantum detection. In particular it is shown the existence of a cutoff value of the average photon number below which quantum crosstalk between AWG ports is negligible with respect to dark counts. These results can be useful when considering the application of AWG devices to integrated quantum photonic systems.
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Osteomyelitis is an infection of the bone, associated with an inflammatory process. Imaging plays an important role in establishing the diagnosis and the most appropriate patient management. However, data are lacking regarding the...
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Osteomyelitis is an infection of the bone, associated with an inflammatory process. Imaging plays an important role in establishing the diagnosis and the most appropriate patient management. However, data are lacking regarding the use of preclinical molecular imaging techniques to assess osteomyelitis progression in experimental models. This study aimed to compare structural and molecular imaging to assess disease progression in a mouse model of implant-related bone and joint infections caused by Staphylococcus aureus . In SWISS mice, the right femur was implanted with a resorbable filament impregnated with S. aureus (infected group, n = 10) or sterile culture medium (uninfected group, n = 6). Eight animals (5 infected, 3 uninfected) were analyzed with magnetic resonance imaging (MRI) at 1, 2, and 3 weeks postintervention, and 8 mice were analyzed with [ 18 F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)-computed tomography (CT) at 48 h and at 1, 2, and 3 weeks postintervention. In infected animals, CT showed bone lesion progression, mainly in the distal epiphysis, although some uninfected animals presented evident bone sequestra at 3 weeks. MRI showed a lesion in the articular area that persisted for 3 weeks in infected animals. This lesion was smaller and less evident in the uninfected group. At 48 h postintervention, FDG-PET showed higher joint uptake in the infected group than in the uninfected group ( P = 0.025). Over time, the difference between groups increased. These results indicate that FDG-PET imaging was much more sensitive than MRI and CT for differentiating between infection and inflammation at early stages. FDG-PET clearly distinguished between infection and postsurgical bone healing (in uninfected animals) from 48 h to 3 weeks after implantation. IMPORTANCE Our results encourage future investigations on the utility of the model for testing different therapeutic procedures for osteomyelitis.
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The key role of the building and construction sector, in terms of sustainability and decarbonization, has led building codes to tighten mandatory requirements related to buildings energy performance. Envelope quality, beyond light...
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The key role of the building and construction sector, in terms of sustainability and decarbonization, has led building codes to tighten mandatory requirements related to buildings energy performance. Envelope quality, beyond light efficiency or the renewable energy contribution, is a key factor since the highest percentage of energy consumption is produced by thermal losses through enclosures. Therefore, building codes have significantly increased the mandatory benchmarks for equivalent thermal transmittance. However, the specific heat capacity (SHC) has commonly been overlooked in the discussion. Thus, in order to estimate the impact of such parameter in the energy consumption and thermal comfort of residential and non-residential buildings, a building model has been simulated by means of Transfer Functions Methods and the Finite Difference Methods. A traditional double brick fa?ade has been considered and the SHC of bricks has been varied from 800 to 1800 kJ/kg K. The thermal behavior of the building has been assessed at several locations in accordance with the Spanish building code. In addition, building orientation has also been shifted from north to south. Although passive strategies have not been considered, the results show significant energy savings (i.e. up to 20%) and a reduction of thermal discomfort (i.e. up to 20%), depending on the type of building and its location.
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This paper compares the equivalent thermal transmittances of different fa?ades built using commercial clay bricks with three different thicknesses and fa?ades made using the same method but with ceramic bricks with optimized rhomb...
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This paper compares the equivalent thermal transmittances of different fa?ades built using commercial clay bricks with three different thicknesses and fa?ades made using the same method but with ceramic bricks with optimized rhomboidal interior geometry.Equivalent thermal transmittances of 0.300 W/m2·K were recorded for the rhomboidal brick with a thickness of 0.290 m and a fa?ade with thermo-acoustic insulation and a large format brick on the interior, but the final thickness of the fa?ade was 0.445 m.For ventilated fa?ades made of the proposed rhomboidal brick with thicknesses of 0.290 and 0.240 m an 8–9% improvement was found, with values of 0.312 W/m2·K and 0.339 W/m2·K, respectively.It can be concluded that in view of the small difference in thermal terms, the best option is to use a brick 0.240 m thick, as the overall thickness of the fa?ade will not then exceed 0.300 m.
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We report the design, fabrication and characterization of an integrated frequency discriminator on InP technology for microwave photonic phase modulated links. The optical chip is, to the best of our knowledge, the first reported ...
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We report the design, fabrication and characterization of an integrated frequency discriminator on InP technology for microwave photonic phase modulated links. The optical chip is, to the best of our knowledge, the first reported in an active platform and the first to include the optical detectors. The discriminator, designed as a linear filter in intensity, features preliminary SFDR values the range between 67 and 79 dB.Hz2/3 for signal frequencies in the range of 5-9 GHz limited, in principle, by the high value of the optical losses arising from the use of several free space coupling devices in our experimental setup. As discussed, these losses can be readily reduced by the use of integrated spot-size converters improving the SFDR by 17.3 dB (84-96 dB.Hz2/3). Further increase up to a range of (104-116 dB.Hz2/3) is possible by reducing the system noise eliminating the EDFA employed in the setup and using a commercially available laser source providing higher output power and lower relative intensity noise. Other paths for improvement requiring a filter redesign to be linear in the optical field are also discussed.
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In this paper the design, fabrication and experimental characterization of an spectral amplitude coded (SAC) optical label swapper monolithically integrated on Indium Phosphide (InP) is presented. The device has a footprint of 4.8...
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In this paper the design, fabrication and experimental characterization of an spectral amplitude coded (SAC) optical label swapper monolithically integrated on Indium Phosphide (InP) is presented. The device has a footprint of 4.8x1.5 mm2 and is able to perform label swapping operations required in SAC at a speed of 155 Mbps. The device was manufactured in InP using a multiple purpose generic integration scheme. Compared to previous SAC label swapper demonstrations, using discrete component assembly, this label swapper chip operates two order of magnitudes faster.
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