Experimental testing of the blind ocean acoustic tomography concept

Acoustic focalization is a well known concept that aims at estimating source location through the adjustment of multiple environmental parameters. This paper uses the same concept for inverting water column sound speed in a blind fashion, where both source location and source emitted waveform are not known at the receiver - that is Blind Ocean Acoustic Tomography (BOAT). The results obtained with BOAT, using ship noise data received on a vertical line array in a shallow water area off the coast of Portugal, show that it is indeed possible to obtain reliable joint estimates of source location and water column sound speed. During that process, it was shown that source range and depth, and Bartlett power, where good indicators of the degree of focus of the model being used.This work was supported by FCT, Portugal, under projects INTIMATE (2/2.1/MAR/1698/95) and ATOMS (PDCTM/P/MAR/15296/1999). The authors are also in debt to the crew of NRP D. Carlos I of IH, that made the sea trial successful

Evaluación del impacto ambiental al extender la vida útil del teléfono móvil

El mercado de telefonía móvil ha experimentado un continuo crecimiento en la última década. Cada vez más, los teléfonos móviles son reemplazados por nuevos modelos con diseños más modernos y ampliación de funciones. Este estilo de vida está provocando incremento en la cantidad de residuos de aparatos electrónicos que no siempre reciben tratamiento. Por lo que, en este artículo, se presentan los resultados de la aplicación de la metodología de análisis de ciclo de vida (ACV) para calcular cuantitativamente el beneficio ambiental debido a la extensión de vida útil del teléfono móvil durante diferentes períodos. Tomando como unidad funcional el ciclo de vida promedio de 30 meses, se modelaron tres escenarios considerando cuatro etapas: adquisición de materias primas/producción, distribución, uso y fin de vida útil. Se utilizó el paquete SimaPro (2013), la base de datos Ecoinvent para configurar el inventario y las emisiones consideradas se asignaron en seis categorías de impacto según el método CML2000 del Centro para Estudios Medioambientales (CML). Se observó que al prolongar la vida útil del teléfono móvil y dar tratamiento cuando se convierte en residuo representa una ganancia ambiental no sólo porque se evita su disposición y consumo de uno nuevo, sino porque se ahorran recursos limitados y la energía necesaria para su extracción a través de la recuperación de materiales. Sin embargo, antes de reciclar es importante considerar su reutilización (extensión de su vida útil) ya que una cantidad sustancial de los móviles son dispuestos por razones de moda o estética mientras aún son funcionales.The mobile phone market has experienced continuous growth over the last decade. Increasingly, mobile phones are replaced by new models with more modern designs or expansion of functions. This lifestyle is causing increasing amount of electronic waste that do not always receive treatment. This article presents the results of the application of the methodology for life-cycle assessment (LCA) to calculate quantitatively the environmental benefit due to the extension of lifespan mobile phones during different periods of time. Taking as a functional unit the life cycle of an average mobile phone during 30 months and considering the stages of raw materials/production, distribution, use and end of life, three scenarios were modeled. The SimaPro (2013) software was used, the Ecoinvent database has been applied to configure the life cycle inventory, and the emissions were allocated into six categories according to the impact CML2000 method. It was observed that to extend the mobile phone useful life and to provide treatment when it becomes a waste, represents an environmental gain not only because the provision and consumption of a new one is avoided, but because limited resources and energy required for extraction are saved through recovery of materials. However, before recycling it is important to consider reuse (extending lifespan) because a substantial amount of the mobile phones are discarded for fashion or cosmetic reasons while they are still functional

The influence of the clay particles on the mechanical properties and fracture behavior of PLA/o-MMT composite films

In this study, calendered films of polylactic acid/organo-montmorillonite clay (PLA/o-MMT) were prepared and the influence of the clay particles' morphology on the mechanical properties and fracture behavior was evaluated. An image analysis was performed using transmission electron microscopy micrographs to complete the morphological study. The micrographs were taken from ultramicrotomic samples corresponding to the melting flow (MD) and transverse direction (TD) of the films. The micrographs revealed intercalated particles and tactoids, which were in accordance with the wide angle X-ray scattering patterns. Uniaxial tensile tests were performed in the MD and TD directions, finding a slight anisotropy in the films, which was associated with a low level of polymer chain orientation due to the calender processing. The fracture behavior was also evaluated in the MD and TD directions using deeply double-edge-notched tension (DDENT) specimens. The mechanical and fracture tests were evaluated on aging (brittle) and deaging (ductile) films by applying a thermal treatment that consisted of heating above the glass transition temperature of the PLA and subsequent quenching. For ductile PLA composite films, the reinforcement effect promoted by the clay particles was not so evident.Peer ReviewedPostprint (author’s final draft

Towards a quasiphase transition in the single-file chain of water molecules: Simple lattice model

Recently, X.Ma et al. [Phys. Rev. Lett. 118, 027402 (2017)] have suggested that water molecules encapsulated in (6,5) single-wall carbon nanotube experience a temperature-induced quasiphase transition around 150 K interpreted as changes in the water dipoles orientation. We discuss further this temperature-driven quasiphase transition performing quantum chemical calculations and molecular dynamics simulations and, most importantly, suggesting a simple lattice model to reproduce the properties of the one-dimensionally confined finite arrays of water molecules. The lattice model takes into account not only the short-range and long-range interactions but also the rotations in a narrow tube and the both ingredients provide an explanation for a temperature-driven orientational ordering of the water molecules, which persists within a relatively wide temperature range.Comment: 15 pages, 10 figure

Technoeconomic and life-cycle analysis of single-step catalytic conversion of wet ethanol into fungible fuel blendstocks

Technoeconomic and life-cycle analyses are presented for catalytic conversion of ethanol to fungible hydrocarbon fuel blendstocks, informed by advances in catalyst and process development. Whereas prior work toward this end focused on 3-step processes featuring dehydration, oligomerization, and hydrogenation, the consolidated alcohol dehydration and oligomerization (CADO) approach described here results in 1-step conversion of wet ethanol vapor (40 wt% in water) to hydrocarbons and water over a metal-modified zeolite catalyst. A development project increased liquid hydrocarbon yields from 36% of theoretical to >80%, reduced catalyst cost by an order of magnitude, scaled up the process by 300-fold, and reduced projected costs of ethanol conversion 12-fold. Current CADO products conform most closely to gasoline blendstocks, but can be blended with jet fuel at low levels today, and could potentially be blended at higher levels in the future. Operating plus annualized capital costs for conversion of wet ethanol to fungible blendstocks are estimated at $2.00/GJ for CADO today and$1.44/GJ in the future, similar to the unit energy cost of producing anhydrous ethanol from wet ethanol ($1.46/GJ). Including the cost of ethanol from either corn or future cellulosic biomass but not production incentives, projected minimum selling prices for fungible blendstocks produced via CADO are competitive with conventional jet fuel when oil is$100 per barrel but not at $60 per barrel. However, with existing production incentives, the projected minimum blendstock selling price is competitive with oil at$60 per barrel. Life-cycle greenhouse gas emission reductions for CADO-derived hydrocarbon blendstocks closely follow those for the ethanol feedstock

Top effective operators at the ILC

We investigate the effect of top trilinear operators in t tbar production at the ILC. We find that the sensitivity to these operators largely surpasses the one achievable by the LHC either in neutral or charged current processes, allowing to probe new physics scales up to 4.5 TeV for a centre of mass energy of 500 GeV. We show how the use of beam polarisation and an eventual energy upgrade to 1 TeV allow to disentangle all effective operator contributions to the Ztt and gamma tt vertices.Comment: LaTeX 13 pages. Typos corrected. Final version in JHE

Top effective operators at the ILC

We investigate the effect of top trilinear operators in t tbar production at the ILC. We find that the sensitivity to these operators largely surpasses the one achievable by the LHC either in neutral or charged current processes, allowing to probe new physics scales up to 4.5 TeV for a centre of mass energy of 500 GeV. We show how the use of beam polarisation and an eventual energy upgrade to 1 TeV allow to disentangle all effective operator contributions to the Ztt and gamma tt vertices.Comment: LaTeX 13 pages. Typos corrected. Final version in JHE

Growth dynamics of morphological and reproductive traits of Physalis peruviana L. M1 plants obtained from seeds irradiated with gamma rays

There is an increasing interest in the development of uchuva (Physalis peruviana L.) cultivars adapted to greenhouse farming. Sexual behavior makes it difficult to obtain uniform commercial uchuva cultivars by conventional breeding methods. Mutations induced by gamma rays is an alternative approach. M1 plants derived from 14 irradiation 60Co doses, from 0 to 275 Gy, that were applied to uchuva seeds were evaluated. Recorded data included days to first flower and growth dynamics (four to seven samplings) of morphological traits (plant height, stem diameter, basal stems) and reproductive traits (floral buds, flowers and green fruits). Treatments were distributed in a completely randomized blocks experimental design with six replications, in a greenhouse. The experimental unit was a single M1 plant. Statistical differences were found for irradiation doses, growth samplings, and its interaction. Growth dynamics results indicate that all traits showed a linear increase with plant age (R2 = 0.92* to 0.98**), but the effect of the irradiation doses on morphological and reproductive traits was no linear. Irradiation reduced plant height by 79%. M1 plants developed from irradiated seeds at doses of 125, 175 and 200 Gy showed greater stem diameter, with more basal stems, floral buds, flowers and green fruits than the control. It is concluded that intermediate irradiation doses had a stimulating effect on vegetative growth and fruiting traits of M1 uchuva plants

Immune system challenge improves recognition memory and reverses malaria-induced cognitive impairment in mice

The immune system plays a role in the maintenance of healthy neurocognitive function. Different patterns of immune response triggered by distinct stimuli may affect nervous functions through regulatory or deregulatory signals, depending on the properties of the exogenous immunogens. Here, we investigate the effect of immune stimulation on cognitive-behavioural parameters in healthy mice and its impact on cognitive sequelae resulting from non-severe experimental malaria. We show that immune modulation induced by a specific combination of immune stimuli that induce a type 2 immune response can enhance long-term recognition memory in healthy adult mice subjected to novel object recognition task (NORT) and reverse a lack of recognition ability in NORT and anxiety-like behaviour in a light/dark task that result from a single episode of mild Plasmodium berghei ANKA malaria. Our findings suggest a potential use of immunogens for boosting and recovering recognition memory that may be impaired by chronic and infectious diseases and by the effects of ageing