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The performance of programmable voltage signals that exploit the quantum behavior of superconducting Josephson junctions continues to improve and enhance measurements in metrology, communications, and quantum control. We review advances in pulse-driven digital synthesis techniques with Josephson-junction-based devices. Quantum-based synthesis of voltage waveforms has been demonstrated at frequencies up to 3 GHz and rms amplitudes up to 4 V. Josephson pulse generators have also been used to control and characterize superconducting qubits. [ABSTRACT FROM AUTHOR]

The liver has a unique ability to regenerate1,2; however, in the setting of acute liver failure (ALF), this regenerative capacity is often overwhelmed, leaving emergency liver transplantation as the only curative option3–5. Here, to advance understanding of human liver regeneration, we use paired single-nucleus RNA sequencing combined with spatial profiling of healthy and ALF explant human livers to generate a single-cell, pan-lineage atlas of human liver regeneration. We uncover a novel ANXA2+ migratory hepatocyte subpopulation, which emerges during human liver regeneration, and a corollary subpopulation in a mouse model of acetaminophen (APAP)-induced liver regeneration. Interrogation of necrotic wound closure and hepatocyte proliferation across multiple timepoints following APAP-induced liver injury in mice demonstrates that wound closure precedes hepatocyte proliferation. Four-dimensional intravital imaging of APAP-induced mouse liver injury identifies motile hepatocytes at the edge of the necrotic area, enabling collective migration of the hepatocyte sheet to effect wound closure. Depletion of hepatocyte ANXA2 reduces hepatocyte growth factor-induced human and mouse hepatocyte migration in vitro, and abrogates necrotic wound closure following APAP-induced mouse liver injury. Together, our work dissects unanticipated aspects of liver regeneration, demonstrating an uncoupling of wound closure and hepatocyte proliferation and uncovering a novel migratory hepatocyte subpopulation that mediates wound closure following liver injury. Therapies designed to promote rapid reconstitution of normal hepatic microarchitecture and reparation of the gut–liver barrier may advance new areas of therapeutic discovery in regenerative medicine.Harnessing single-nucleus RNA sequencing and spatial profiling, this work dissects unanticipated aspects of human liver regeneration to uncover a novel migratory hepatocyte subpopulation mediating wound closure following acute liver injury. [ABSTRACT FROM AUTHOR]

Compared to traditional semiconductor control electronics (TSCE) located at room temperature, cryogenic single flux quantum (SFQ) electronics can provide qubit measurement and control alternatives that address critical issues related to scalability of cryogenic quantum processors. Single-qubit control and readout have been demonstrated recently using SFQ circuits coupled to superconducting qubits. Experiments where the SFQ electronics are co-located with the qubit have suffered from excess decoherence and loss due to quasiparticle poisoning of the qubit. A previous experiment by our group showed that moving the control electronics to the 3 K stage of the dilution refrigerator avoided this source of decoherence in a high-coherence three-dimensional transmon geometry. In this paper, we also generate the pulses at the 3 K stage but have optimized the qubit design and control lines for scalable two-dimensional transmon devices. We directly compare the qubit lifetime T 1 , coherence time T 2 * , and gate fidelity when the qubit is controlled by the Josephson pulse generator (JPG) circuit vs the TSCE setup. We find agreement within the daily fluctuations for T 1 and T 2 * , and agreement within 10% for randomized benchmarking. We also performed interleaved randomized benchmarking on individual JPG gates demonstrating an average error per gate of 0.46% showing good agreement with what is expected based on the qubit coherence and higher-state leakage. These results are an order of magnitude improvement in gate fidelity over our previous work and demonstrate that a Josephson microwave source operated at 3 K is a promising component for scalable qubit control. [ABSTRACT FROM AUTHOR]

Introduction: Significant and persistent racial and ethnic disparities exist related to infant mortality and other birth outcomes. Few models exist that aim to prepare organizations to implement essential features, such as community engagement or intervening on social determinants of health. Methods: Between 2013 and 2015, teams from seven local health departments participated in the Institute for Equity in Birth Outcomes (EI) with the goals of building capacity and implementing changes to address equity in birth outcomes. Four of the teams enrolled in the first cohort (2013–2015), and three enrolled in cohort two (2014–2015). To examine the EI effort and its impact on capacity and implementation of changes, two types of assessments were completed. Capacities of the teams in specific key areas were assessed using "Best Change Process" instruments at the completion of participation in the EI. Teams also documented on an ongoing basis implementation of interventions. The data were analyzed using descriptive statistics and Pearson Correlation tests. Results: Best Change Process capacity scores were higher in the first cohort than in the second and were highly correlated with implementation of changes (Pearson's Correlation = 0.838, p = 0.037). Collectively, the teams implemented about 32 new programs, policies, practices, and systems changes aimed at addressing equity in birth outcomes. Most interventions were based on scientific recommendations and local epidemiologic data. Discussion: The results of the study suggest the EI is a promising approach that may result in strong capacity and ability to implement interventions aimed at addressing equity in birth outcomes. [ABSTRACT FROM AUTHOR]

The SEDIGISM (Structure, Excitation and Dynamics of the Inner Galactic Interstellar Medium) survey used the APEX telescope to map 84 deg2 of the Galactic plane between ℓ = −60° and +31° in several molecular transitions, including 13CO (2 – 1) and C18O (2 – 1), thus probing the moderately dense (∼103 cm−3) component of the interstellar medium. With an angular resolution of 30 arcsec and a typical 1 σ sensitivity of 0.8–1.0 K at 0.25 km s−1 velocity resolution, it gives access to a wide range of structures, from individual star-forming clumps to giant molecular clouds and complexes. The coverage includes a good fraction of the first and fourth Galactic quadrants, allowing us to constrain the large-scale distribution of cold molecular gas in the inner Galaxy. In this paper, we provide an updated overview of the full survey and the data reduction procedures used. We also assess the quality of these data and describe the data products that are being made publicly available as part of this First Data Release (DR1). We present integrated maps and position–velocity maps of the molecular gas and use these to investigate the correlation between the molecular gas and the large-scale structural features of the Milky Way such as the spiral arms, Galactic bar and Galactic Centre. We find that approximately 60 per cent of the molecular gas is associated with the spiral arms and these appear as strong intensity peaks in the derived Galactocentric distribution. We also find strong peaks in intensity at specific longitudes that correspond to the Galactic Centre and well-known star-forming complexes, revealing that the 13CO emission is concentrated in a small number of complexes rather than evenly distributed along spiral arms. [ABSTRACT FROM AUTHOR]

Three types of iron-based oxide nanoparticles (weight compositions Fe[sub 2]O[sub 3], BaFe[sub 2]O[sub 4], and BaFe[sub 12]O[sub 19]) embedded in a polyethylene matrix are studied using the electron paramagnetic resonance technique. All nanoparticles are found to be multiphase. Thermal variations of electron paramagnetic resonance spectra reveal the presence of two phases in the Fe[sub 2]O[sub 3] nanoparticles. One such phase undergoes an antiferromagnetic-like transition near 6 K. Nanoparticles of BaFe[sub 2]O[sub 4] demonstrate a resonance anomaly near 125 K that could indicate the presence of a magnetic phase. Reduced magnetic anisotropy in BaFe[sub 12]O[sub 19] nanoparticles may be related to either structural imperfection or particle smallness (effective diameter of less than 10 nm). Our data clearly show that low temperature experiments are desirable for the correct identification of nanoparticles by means of the electron paramagnetic resonance technique. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Studies the electron paramagnetic resonance of Fe-based nanoparticles embedded in polyethylene matrix as a function of temperature. Temperature-driven transition from superparamagnetic to ferromagnetic resonance observed for samples with different Fe content.

Aims. In order to understand the observed molecular diversity in high-mass star-forming regions, we have to determine the underlying physical and chemical structure of those regions at high angular resolution and over a range of evolutionary stages. Methods. We present a detailed observational and modeling study of the hot core VLA 3 in the high-mass star-forming region AFGL 2591, which is a target region of the NOrthern Extended Millimeter Array (NOEMA) large program CORE. Using NOEMA observations at 1.37 mm with an angular resolution of ~0″. 42 (1400 au at 3.33 kpc), we derived the physical and chemical structure of the source. We modeled the observed molecular abundances with the chemical evolution code MUSCLE (MUlti Stage ChemicaL codE). Results. With the kinetic temperature tracers CH3CN and H2CO we observe a temperature distribution with a power-law index of q = 0.41 ± 0.08. Using the visibilities of the continuum emission we derive a density structure with a power-law index of p = 1.7 ± 0.1. The hot core spectra reveal high molecular abundances and a rich diversity in complex molecules. The majority of the molecules have an asymmetric spatial distribution around the forming protostar(s), which indicates a complex physical structure on scales <1400 au. Using MUSCLE, we are able to explain the observed molecular abundance of 10 out of 14 modeled species at an estimated hot core chemical age of ~21 100 yr. In contrast to the observational analysis, our chemical modeling predicts a lower density power-law index of p < 1.4. Reasons for this discrepancy are discussed. Conclusions. Combining high spatial resolution observations with detailed chemical modeling allows us to derive a concise picture of the physical and chemical structure of the famous AFGL 2591 hot core. The next steps are to conduct a similar analysis for the whole CORE sample, and then use this analysis to constrain the chemical diversity in high-mass star formation to a much greater depth. [ABSTRACT FROM AUTHOR]

In Puerto Rico, the first records of the transmission of Chikungunya (CHIKV) and Zika (ZIKV) viruses were confirmed in May 2014 and December 2015, respectively. Transmission of CHIKV peaked in September 2014, whereas that of ZIKV peaked in August 2016. The emergence of these mosquito‐transmitted arboviruses in the context of a lack of human population immunity allowed observations of whether the outbreaks were associated with Aedes aegypti (Diptera: Culicidae) densities and weather. Mosquito density was monitored weekly in four communities using sentinel autocidal gravid ovitraps (AGO traps) during 2016 in order to provide data to be compared with the findings of a previous study carried out during the 2014 CHIKV epidemic. Findings in two communities protected against Ae. aegypti using mass AGO trapping (three traps per house in most houses) were compared with those in two nearby communities without vector control. Mosquito pools were collected to detect viral RNA of ZIKV, CHIKV and dengue virus. In areas without vector control, mosquito densities and rates of ZIKV detection in 2016 were significantly higher, similarly to those observed for CHIKV in 2014. The density of Ae. aegypti in treated sites was less than two females/trap/week, which is similar to the putative adult female threshold for CHIKV transmission. No significant differences in mosquito density or infection rates with ZIKV and CHIKV at the same sites between years were observed. Although 2016 was significantly wetter, mosquito densities were similar. In Puerto Rico, mosquito densities and rates of Zika virus (ZIKV) detection in 2016 were significantly higher in areas without vector control, similarly to those observed for Chikungunya virus (CHIKV) in 2014.The density of Aedes aegypti in sites treated with mass trapping was under two females/trap/week, which is similar to the putative adult female threshold for CHIKV transmission.There were no significant differences in mosquito density or infection rates with ZIKV and CHIKV at the same sites between years. [ABSTRACT FROM AUTHOR]

Abstract: Recycled aggregates (RA) have been extensively studied in the production of concrete. Normally, the coarse fraction of recycled concrete aggregates (RCA) is the most commonly used to manufacture recycled concretes. The manufacturing of concrete with fine fraction of RCA and/or recycled mixed aggregates (RMA) (from a mix of concrete, asphalt, masonry, etc.) has not been studied in depth. In most cases, the recycling plants produce RA with an ALL-IN particle size distribution. These recycled materials could be named as ALL-IN RECYCLED CONCRETE AGGREGATES (aiRCA) and ALL-IN RECYCLED MIXED AGGREGATES (aiRMA). Applying these aiRCA or aiRMA, limiting the percentage of the substitution of natural aggregates (NA) by the aiRCA, is more beneficial for both the production costs and the environment. In recent studies, other by-products, such as biomass bottom ash (BBA) were used in concretes, substituting natural sand (NS) and improving the mechanical properties in concretes with low quantities of cement. It is possible to improve the properties of the BBA via mechanical processes (like screening or flotation) to reduce the organic matter content and there by obtain processed BBA (Pr-BBA). This study provides interesting data on the mechanical and durability properties of the concretes manufactured with 30% aiRCA and aiRMA, and also by applying different replacement rates (0, 15, and 30%) of NA by BBA and Pr-BBA. The mechanical and durability properties were analysed over different time durations in different mixtures. It was demonstrated that it is possible to apply these recycled materials in non-structural concrete mixtures by limiting the replacement rate. The application of BBA and Pr-BBA reduced the properties of the concrete. However, this reduction was less significant with the use of Pr-BBA.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Summary: The seismic design of optimal damped outrigger structures relies on the assumption that most of the input energy will be absorbed by the dampers, whilst the rest of the structure remains elastic. When subjected to strong earthquakes, nevertheless, the building structure may exhibit plastic hinges before the dampers begin to work. In order to determine to which extent the use of viscously damped outriggers would avoid damage, both the host structure's hysteretic behaviour and the dampers' performance need to be evaluated in parallel. This article provides a parametric study on the factors that influence the distribution of seismic energy in tall buildings equipped with damped outriggers: First, the influence of outrigger's location, damping coefficients, and rigidity ratios core‐to‐outrigger and core‐to‐column in the seismic performance of a 60‐story building with conventional and with damped outriggers is studied. In parallel, nonlinear behaviour of the outrigger with and without viscous dampers is examined under small, moderate, strong, and severe long‐period earthquakes to assess the hysteretic energy distribution through the core and outriggers. The results show that, as the ground motion becomes stronger, viscous dampers effectively reduce the potential of damage in the structure if compared to conventional outriggers. However, the use of dampers cannot entirely prevent damage under critical excitations. [ABSTRACT FROM AUTHOR]

Background. Aims were to assess the efficacy of metacognitive training (MCT) in people with a recent onset of psychosis in terms of symptoms as a primary outcome and metacognitive variables as a secondary outcome. Method. A multicenter, randomized, controlled clinical trial was performed. A total of 126 patients were randomized to an MCT or a psycho-educational intervention with cognitive-behavioral elements. The sample was composed of people with a recent onset of psychosis, recruited from nine public centers in Spain. The treatment consisted of eight weekly sessions for both groups. Patients were assessed at three time-points: baseline, post-treatment, and at 6 months follow- up. The evaluator was blinded to the condition of the patient. Symptoms were assessed with the PANSS and metacognition was assessed with a battery of questionnaires of cognitive biases and social cognition. Results. Both MCT and psycho-educational groups had improved symptoms post-treatment and at follow-up, with greater improvements in the MCT group. The MCT group was superior to the psycho-educational group on the Beck Cognitive Insight Scale (BCIS) total (p = 0.026) and self-certainty (p = 0.035) and dependence self-subscale of irrational beliefs, comparing baseline and post-treatment. Moreover, comparing baseline and follow-up, the MCT group was better than the psycho-educational group in self-reflectiveness on the BCIS (p = 0.047), total BCIS (p = 0.045), and intolerance to frustration (p = 0.014). Jumping to Conclusions (JTC) improved more in the MCT group than the psycho-educational group (p = 0.021). Regarding the comparison within each group, Theory of Mind (ToM), Personalizing Bias, and other subscales of irrational beliefs improved in the MCT group but not the psycho-educational group (p < 0.001-0.032). Conclusions. MCT could be an effective psychological intervention for people with recent onset of psychosis in order to improve cognitive insight, JTC, and tolerance to frustration. It seems that MCT could be useful to improve symptoms, ToM, and personalizing bias. [ABSTRACT FROM AUTHOR]

Resumen Objetivos Evaluar el uso de la 4D PET/TC para capturar el movimiento respiratorio en comparación con la «slow»-TC (TCs), en el procedimiento de planificación de radioterapia. Material y métodos Se ha incluido a 25 pacientes diagnosticados de estadio inicial de cáncer de pulmón de célula no pequeña (NSCLC) médicamente inoperable. A cada paciente se le realizó una TCs (4 s/corte) y una 4D PET/TC. La idoneidad de cada técnica en la captura del movimiento respiratorio fue evaluada comparando el volumen definido por cada una de ellas: internal target volumen (ITV) 4D y el ITVslow, con relación a la suma de los volúmenes de la 4D PET/TC y la TCs (ITVsuma). La máxima diferencia entre el volumen definido por cada técnica respecto al volumen suma fue evaluada en una proyección antero-posterior y otra lateral. Resultados Los volúmenes generados con 4D PET/TC consiguen una definición más precisa del ITV que los volúmenes obtenidos con TCs (ITV4D/ITVsuma 78% vs. ITVslow/ITVsuma 63%). En general, los volúmenes de la 4D PET/TC son de mayor tamaño (19,9 vs. 16,3 cc). El ITV4D muestra menor diferencia con el ITVsuma en los ejes cráneo-caudal y antero-posterior respecto al ITVslow y capta el movimiento de forma más exacta. La máxima diferencia observada es de 0,36 mm en la 4D PET/TC y de 0,57 mm en la TCs en el eje antero-posterior. Conclusiones La planificación con 4D PET/TC en comparación con TCs permite cuantificar el movimiento respiratorio del tumor y mejorar la planificación de radioterapia en estadios iniciales de NSCLC. Objectives To evaluate the use of 4D PET/CT to quantify tumor respiratory motion compared to the «Slow»-CT (CTs) in the radiotherapy planning process. Material and methods A total of 25 patients with inoperable early stage non small cell lung cancer (NSCLC) were included in the study. Each patient was imaged with a CTs (4s/slice) and 4D PET/CT. The adequacy of each technique for respiratory motion capture was evaluated using the volume definition for each of the following: Internal target volume (ITV) 4D and ITVslow in relation with the volume defined by the encompassing volume of 4D PET/CT and CTs (ITVtotal). The maximum distance between the edges of the volume defined by each technique to that of the total volume was measured in orthogonal beam's eye view. Results The ITV4D showed less differences in relation with the ITVtotal in both the cranio-caudal and the antero-posterior axis compared to the ITVslow. The maximum differences were 0.36 mm in 4D PET/CTand 0.57 mm in CTs in the antero-posterior axis. 4D PET/CT resulted in the definition of more accurate (ITV4D/ITVtotal 0.78 vs. ITVs/ITVtotal 0.63), and larger ITVs (19.9 cc vs. 16.3 cc) than those obtained with CTs. Conclusion Planning with 4D PET/CT in comparison with CTs, allows incorporating tumor respiratory motion and improving planning radiotherapy of patients in early stages of lung cancer. [ABSTRACT FROM AUTHOR]

Myopodin is a cytoskeleton protein that shuttles to the nucleus depending on the cellular differentiation and stress. It has shown tumor suppressor functions. Myopodin methylation status was useful for staging bladder and colon tumors and predicting clinical outcome. To our knowledge, myopodin has not been tested in kidney cancer to date. The purpose of this study was to evaluate whether myopodin methylation status could be clinically useful in renal cancer (1) as a prognostic biomarker and 2) as a predictive factor of response to antiangiogenic therapy in patients with metastatic disease. Methylation-specific polymerase chain reactions (MS-PCR) were used to evaluate myopodin methylation in 88 kidney tumors. These belonged to patients with localized disease and no evidence of disease during follow-up ( n = 25) (group 1), and 63 patients under antiangiogenic therapy (sunitinib, sorafenib, pazopanib, and temsirolimus), from which group 2 had non-metastatic disease at diagnosis ( n = 32), and group 3 showed metastatic disease at diagnosis ( n = 31). Univariate and multivariate Cox analyses were utilized to assess outcome and response to antiangiogenic agents taking progression, disease-specific survival, and overall survival as clinical endpoints. Myopodin was methylated in 50 out of the 88 kidney tumors (56.8 %). Among the 88 cases analyzed, 10 of them recurred (11.4 %), 51 progressed (57.9 %), and 40 died of disease (45.4 %). Myopodin methylation status correlated to MSKCC Risk score ( p = 0.050) and the presence of distant metastasis ( p = 0.039). Taking all patients, an unmethylated myopodin identified patients with shorter progression-free survival, disease-specific survival, and overall survival. Using also in univariate and multivariate models, an unmethylated myopodin predicted response to antiangiogenic therapy (groups 2 and 3) using progression-free survival, disease-specific, and overall survival as clinical endpoints. Myopodin was revealed hypermethylated in kidney cancer. Myopodin methylation status identified which patients showed a more aggressive clinical behavior and predicted antiangiogenic response. These observations support the clinical utility of an unmethylated myopodin as a prognostic and predictive biomarker in kidney cancer. [ABSTRACT FROM AUTHOR]

In superconducting quantum information, machined aluminum superconducting cavities have proven to be a well-controlled, low-dissipation electromagnetic environment for quantum circuits such as qubits. They can possess large internal quality factors, Qint > 108, and present the possibility of storing quantum information for times far exceeding those of microfabricated circuits. However, in order to be useful as a storage element, these cavities require a fast "read/write" mechanism--in other words, they require tunable coupling between other systems of interest such as other cavity modes and qubits, as well as any associated readout hardware. In this work, we demonstrate these qualities in a simple dual cavity architecture in which a low-Q "readout" mode is parametrically coupled to a high-Q "storage" mode, allowing us to store and retrieve classical information. Specifically, we employ a flux-driven Josephson junction-based coupling scheme to controllably swap coherent states between two cavities, demonstrating full, sequenced control over the coupling rates between modes. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the reduction of infection risk due to exposure to Salmonella sp. in kitchen cleaning clothes by the use of a bleach (sodium hypochlorite) cleaner utilizing a continuous-time dynamic exposure model. The only route of exposure considered was hand contamination during cloth use. The occurrence and numbers of Salmonella was studied in 60 homes over a 6-week period in which half disinfected kitchen cleaning clothes with a sodium hypochlorite based disinfectant cleaner. This study demonstrated that a significant risk exists for Salmonella infection from kitchen cleaning clothes in Mexican homes and that this risk can be reduced by almost 100-fold by soaking cleaning clothes in a bleach product. The risks of infection and illness could likely be further reduced by developing a more effective procedure for reducing Salmonella in cleaning clothes treated twice a day with a sodium hypochlorite disinfectant (i.e. longer soaking time) or using a greater concentration of the disinfectant. Significance and Impact of the Study Hygiene intervention is a key strategy to reduce the potential risk of disease-causing micro-organisms in households. There is a lack of understanding of the human health risk associated with the use of contaminated kitchen cleaning cloths. The study used a quantitative microbial risk assessment to estimate the risk associated with the use of kitchen cleaning clothes by using disinfectant products. The results showed that the use of prescribe protocols can reduce the risk of Salmonella infections in household kitchens. [ABSTRACT FROM AUTHOR]

We have fabricated large arrays of mesoscopic metal rings on ultrasensitive cantilevers. The arrays are defined by electron beam lithography and contain up to 105 rings. The rings have a circumference of 1 µm, and are made of ultrapure (6N) Au that is deposited onto a silicon-on-insulator wafer without an adhesion layer. Subsequent processing of the SOI wafer results in each array being supported at the end of a free-standing cantilever. To accommodate the large arrays while maintaining a low spring constant, the cantilevers are nearly 1 mm in both lateral dimensions and 100 nm thick. The extreme aspect ratio of the cantilevers, the large array size, and the absence of a sticking layer are intended to enable measurements of the rings' average persistent current (I) in the presence of relatively small magnetic fields. We describe the motivation for these measurements, the fabrication of the devices, and the characterization of the cantilevers' mechanical properties. We also discuss the devices' expected performance in measurements of (I). [ABSTRACT FROM AUTHOR]

Borderline resectable pancreatic head carcinoma is a challenging disease that requires multidisciplinary approach to obtain maximal benefits from current therapeutical possibilities. We review current knowledge and therapeutic options for the patients from the surgical, medical oncology and radiotherapy views and emphasize the need for a coordinated multidisciplinary approach to obtain optimal results. [ABSTRACT FROM AUTHOR]

The La- Lantejuela playa-lakes endorheic complex is a groundwater-dependent ecosystem located within the Guadalquivir River Basin ( Southern Spain) in an area mainly devoted to agriculture production with increasing groundwater extractions for irrigation from the Osuna- La Lantejuela ( O- LL) aquifer. The O- LL aquifer was hydrogeologically characterised in previous works made by the authors. New data and the combination of more field observations, together with the use of morphologic indexes of the playa lakes, has permitted to analyse the relationships between the aquifer and each one of the playa lakes in the complex, assessing whether their hydrological functioning would have been affected by the expansion of irrigated agriculture. Furthermore, the analysis of the results obtained has allowed establishing a hypothesis of the hydrological functioning of the whole system under natural conditions. This case study represents a useful example to understand how agriculture in semi-arid environments can induce alterations on the wetlands hydrological functioning. [ABSTRACT FROM AUTHOR]

An impulse-radio ultrawideband (UWB) photonic generation technique based on frequency shifting in the remote connectivity fiber in optical access networks is proposed and analyzed in this paper. This technique is based on optical carrier suppression modulation combined with fiber chromatic dispersion targeting to overcome the bandwidth limitation of optical upconversion, with the advantage of being easily reconfigurable generating simultaneously different RF bands. A comprehensive simulation analysis is performed with special focus on capabilities for dual 24 GHz/60 GHz operation paired with experimental demonstration at 1.24 Gb/s. 60 GHz wireless performance after optical generation and transmission in 12.5 km of standard single-mode fiber is measured demonstrating error-free transmission at 1 m radio distance. The inclusion of remote Gaussian-monocycle pulse shaping is also analyzed in this paper considering dual 24 GHz/60 GHz operation. Pulse-shaped dual 24 GHz/60 GHz generation is experimentally demonstrated at 1.24 Gb/s. Transmission performance is measured at 24 GHz demonstrating error-free transmission. The simulation analysis further indicates that the technique is suitable for UWB generation at higher RF bands such as the W-band (75-110 GHz). Practical implementation considerations and trade-offs (e.g., in terms of cost and number of remote antenna units supported) of this system are also analyzed by simulation showing that the technique is cost effective. [ABSTRACT FROM PUBLISHER]

Nowadays limestone powder and blast furnace slag (BFS) are widely used in concrete as blended materials in cement. The replacement of Portland cement by limestone powder and BFS can lower the cost and enhance the greenness of concrete, since the production of these two materials needs less energy and causes less CO2 emission than Portland cement. Moreover, the use of limestone powder and BFS improves the properties of fresh and hardened concrete, such as workability and durability. Engineered cementitious composites (ECC) is a class of ultra ductile fiber reinforced cementitious composites, characterized by high ductility, tight crack width control and relatively low fiber content. The limestone powder and BFS are used to produce ECC in this research. The mix proportion is designed experimentally by adjusting the amount of limestone powder and BFS, accompanied by four-point bending test and uniaxial tensile test. This study results in an ECC mix proportion with the Portland cement content as low as 15% of powder by weight. This mixture, at 28 days, exhibits a high tensile strain capacity of 3.3%, a tight crack width of 57 μm and a moderate compressive strength of 38 MPa. In order to promote a wide use of ECC, it was tried to simplify the mixing of ECC with only two matrix materials, i.e. BFS cement and limestone powder, instead of three matrix materials. By replacing Portland cement and BFS in the aforementioned ECC mixture with BFS cement, the ECC with BFS cement and limestone powder exhibits a tensile strain capacity of 3.1%, a crack width of 76 μm and a compressive strength of 40 MPa after 28 days of curing. [ABSTRACT FROM AUTHOR]

Nanomechanical oscillators are at the heart of ultrasensitive detectors of force, mass and motion. As these detectors progress to even better sensitivity, they will encounter measurement limits imposed by the laws of quantum mechanics. If the imprecision of a measurement of the displacement of an oscillator is pushed below a scale set by the standard quantum limit, the measurement must perturb the motion of the oscillator by an amount larger than that scale. Here we show a displacement measurement with an imprecision below the standard quantum limit scale. We achieve this imprecision by measuring the motion of a nanomechanical oscillator with a nearly shot-noise limited microwave interferometer. As the interferometer is naturally operated at cryogenic temperatures, the thermal motion of the oscillator is minimized, yielding an excellent force detector with a sensitivity of 0.51 aN Hz−1/2. This measurement is a critical step towards observing quantum behaviour in a mechanical object. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the foaming process of a commercial polyethylene in the presence of a crosslinking agent. It mentioned that foams have been produced under nearly atmospheric conditions. It found that under a specific processing temperatures and with an accurate formulation, foam densities have been reduced up to 70% with respect to non-foamed polymer.