Optical properties of apple skin and flesh in the wavelength range from 350 to 2200 nm

Optical measurement of fruit quality is challenging due to the presence of a skin around the fruit flesh and the multiple scattering by the structured tissues. To gain insight in the light-tissue interaction, the optical properties of apple skin and flesh tissue are estimated in the 350-2200nm range for three cultivars. For this purpose, single integrating sphere measurements are combined with inverse adding- doubling. The observed absorption coefficient spectra are dominated by water in the near infrared and by pigments and chlorophyll in the visible region, whose concentrations are much higher in skin tissue. The scattering coefficient spectra show the monotonic decrease with increasing wavelength typical for biological tissues with skin tissue being approximately three times more scattering than flesh tissue. Comparison to the values from time-resolved spectroscopy reported in literature showed comparable profiles for the optical properties, but overestimation of the absorption coefficient values, due to light losses

Trend in ice moistening the stratosphere – constraints from isotope data of water and methane

Water plays a major role in the chemistry and radiative budget of the stratosphere. Air enters the stratosphere predominantly in the tropics, where the very low temperatures around the tropopause constrain water vapour mixing ratios to a few parts per million. Observations of stratospheric water vapour show a large positive long-term trend, which can not be explained by change in tropopause temperatures. Trends in the partitioning between vapour and ice of water entering the stratosphere have been suggested to resolve this conundrum. We present measurements of stratospheric H_(2)O, HDO, CH_4 and CH_(3)D in the period 1991–2007 to evaluate this hypothesis. Because of fractionation processes during phase changes, the hydrogen isotopic composition of H_(2)O is a sensitive indicator of changes in the partitioning of vapour and ice. We find that the seasonal variations of H_(2)O are mirrored in the variation of the ratio of HDO to H_(2)O with a slope of the correlation consistent with water entering the stratosphere mainly as vapour. The variability in the fractionation over the entire observation period is well explained by variations in H_(2)O. The isotopic data allow concluding that the trend in ice arising from particulate water is no more than (0.01±0.13) ppmv/decade in the observation period. Our observations suggest that between 1991 and 2007 the contribution from changes in particulate water transported through the tropopause plays only a minor role in altering in the amount of water entering the stratosphere

New methods for measuring and monitoring chromatic dispersion in optical communication systems

This PFC main goal is to introduce new approaches on the chromatic dispersion measurement field, based on the big range of possibilities the setup of a general standard RF-tone modulation chromatic modulation method provides, and to show its good performance pointing towards a real-time on-line monitoring system for optical communication networks. The project’s objectives are defined considering two well-delimited stages. First, we will study some standard RF-tone-addition techniques for measuring chromatic dispersion, specifically the Modulation Phase Shift Method (MPSM) [2] and the Peucheret`s Method [3]. We will analyze their operating principles, recognize all the variables involved in their basic configurations and evaluate their performances under different measurement conditions. We will also study the implications of real-time on-line monitoring of chromatic dispersion in optical networks. We have to consider that the test signal has to travel together with the data; therefore, it is a priority to keep the optical carrier unaltered in the transmission and reception procedures. This background will help us to identify the main drawbacks of both methods which motivate the proposal of a new improved technique based on a similar mathematical basis but with better performance in terms of accuracy and cost trade-off. The general features of this new approach will be exposed on a basic setup designed for a laboratory environment, so that we can contrast it with the conventional techniques. This method dubbed Asymmetric Modulation Bias-Controlled Method (ABCM) will focus on RF modulated signal amplitude and will take advantage of its direct relation with chromatic dispersion. One of the basic building blocks of these standard methods is the device that imposes the RF pure-tone modulation to the optical signal, namely the Mach-Zehnder interferometric modulator usually in the conventional push-pull configuration and biased at the quadrature point. In the context of the new improved CD measurement methods, we will observe how the Mach-Zehnder modulator Bias Voltage concept gains relevance; becoming the main variable to be handled by the use of a dual drive Mach-Zehnder modulator in asymmetric configuration. Finally, we will analyze this ABCM method performance while some fixed parameters (RF Frequency, Nominal Dispersion, resolution) take different values in order to find out the optimum operating conditions. The problem when trying to apply the ABCM to the real-time on-line monitoring of optical networks is that it relies in the eventual cancellation of the optical carrier which in a network monitoring application is shared with the data and it is essential for a proper data recovery. We must find an alternative where this optical carrier cancellation is not essential for the monitoring function and that would be the ABCM-SC (SC for suppressed carrier) Therefore, on a second stage, we will focus on giving this new perspective about dispersion measurement a direct application in optical communications field. We will restructure the ABCM into a practical dispersion monitoring system for optical communication networks. This improved monitoring technique will be based on a proof-of-concept study (no real data transmission considered) to evaluate the method’s performance in terms of accuracy, robustness and adaptability, building the basis for data transmission experiments in future projects. An important aspect to take into account will be the way we carry out the RF tone addition procedure without altering the optical carrier (transmitted data). To accomplish this requirement we will use a Bessel function analysis to achieve a carrier-suppressed modulation of the RF tone, which introduces another important handling parameter: the RF Tone Amplitude. We will also be concerned about isolating the emitter part (where data is transmitted) from the monitoring point (where dispersion is measured), but at the same time complementing each other to operate in a real-time situation. Finally, we will study the requirement of including the second RF harmonic detection together with the first harmonic as it adjusts better to a real-time monitoring system and increases the accuracy level in chromatic dispersion measurement

LOS MECANISMOS DE DEFENSA COMERCIAL EN EL PARAGUAY

El presente trabajo tiene por objeto hacer conocer los Mecanismos deDefensa Comercial que se tiene a disposición para enfrentar la competenciadesleal de importaciones, o de incrementos significativos en el volumen delas importaciones realizadas en condiciones tales, que estén ocasionando oamanezando ocasionar un daño importante a una rama de la producciónnacional

Nutritional value of four pest animals to be used in feeding monogastric organisms

[ES] Las muestras de animales plagas fueron colectadas, secadas y molidas. Estas fueron analizadas para determinar su contenido en proteína, cenizas y aminoácidos. Los análisis bromatológicos mostraron que Achatina fulica y Pieris brassica, contienen más proteína bruta, (PB) (779.2 y 812.2 g/kg) en comparación a Phyllophaga spp. y Spodoptera frugierda (432. 5 y 445.7 g/ kg). Comparando el perfil de aminoácidos, A. fulica y P. brassica obtuvieron los niveles más altos en la mayoría de los amino ácidos esenciales (AAE) que la torta de soya y en el caso de A. fulica, éste exhibió valores más altos que la harina de pescado en arginina, cisteina, glicina, serina y tirosina. Observando la relación de AAE/AANE (amino ácidos no esenciales) en las harinas, sólo S. frugiperda presentó valores similares a la harina de pescado (0.85). Todas las harinas de animales plagas presentaron una reducción en la cuantificación de amino ácidos en relación con los valores de PB obtenidos por el método de Kjeldahl, esta reducción se encontraba entre 28.6 y 38.0%. Esta disminución podría deberse a la combinación entre la proteína y la quitina que se encuentran en el cuerpo de los insectos. A pesar de esta reducción la cuantificación de amino ácidos de los animales plagas podría ser una buena alternativa para su uso en la alimentación de monogástricos, especialmente para peces y crustáceos.[EN] The pest samples were collected, dried, and grounded. They were analysed to determinate contain of protein, energy, ashes and amino acids. The bromatological analysis showed that Achatina fulica and Pieris brassica, obtained a higher amount of crude protein (CP) (779.2 and 812.2 g/kg) in comparison to Phyllophaga spp. and Spodoptera frugiperda (432.5 and 455.7 g/kg). Comparing the amino acids profile, A. fulica and P. brassica obtained higher values in most of the essential amino acids (EAA) than soybean meal, and A. fulica exhibited even higher values than fish meal (FM) in Arginine, Cysteine, Glycine, Serine, and Tyrosine. Observing the relation of EAA/NEEA (no essential amino acids) in all the meals only S. frugiperda presented a similar value to fish meal (0.85). All the pest meals presented a reduction in the amino acids quantification in comparison to the CP values obtained by the Kjeldahl method, with reduction between 28.6 through 38.0%. This diminution could be due to the linkage of the protein to the chitin content of the insect body. In spite of the reduction of the amino acids quantification, the pest meals could be an alternative in feeding monogastric organisms, especially fish and crustaceans.To the Polytechnic University of Valencia for it support.Nogales Mérida, S.; Velazco Vargas, JL.; Martínez-Llorens, S.; Tomas-Vidal, A. (2018). Nutritional value of four pest animals to be used in feeding monogastric organisms. Archivos de Zootecnia. 67(258):278-282. https://doi.org/10.21071/az.v67i258.3664S2782826725

Evaluation of soybean meal as protein source for Argyrosomus Regius (Asso, 1801) (Sciaenidae)

[EN] The meagre (Argyrosomus regius) is a carnivorous fish which requires diets with higher protein content, causing an increment in diets cost. A way to diminish this cost is to use vegetable meals like soybean meal (SB). So the aim of this trial was to determine the optimum inclusion level of defatted soybean meal in experimental diets for this species. 800 fishes (165 g) were distributed in 8 tanks, two replicates per treatment. Four isoproteic (50% CP) and isolipidic (17% Cl) diets were formulated with four levels of soybean meal inclusion, 0, 15, 30 and 45%. The trial lasted 107 days. Meagre fed diets 15 and 30% obtained the highest final weight. There were no significant differences among treatments in the feed conversion rate (FCR) and the protein efficiency (PER). According to the quadratic regression, the optimum SB inclusion to maximize thermal growth coefficient (TGC) was 26.4% and for FCR was 27.6%. No significant differences were observed in energy, protein and amino acid retention among diets. The inclusion of SB in meagre diets can generate a decrease in the use of fish meal and in turn reduce the cost of producing meagre Mediterranean aquaculture industry.Velazco Vargas, JL.; Martínez-Llorens, S.; Jover Cerda, M.; Tomas-Vidal, A. (2013). Evaluation of soybean meal as protein source for Argyrosomus Regius (Asso, 1801) (Sciaenidae). International Journal of Fisheries and Aquaculture. 5(3):25-44. doi:10.5897/IJFA12.062S25445

Single event effects in static and dynamic registers in a 0.25−μ−m0.25-\mu-m CMOS technology

We have studied single event effects in static and dynamic registers designed in a quarter micron CMOS process. In our design, we systematically used guardrings and enclosed (edgeless) transistor geometry to improve the total dose tolerance. This design technique improved both the SEL and SEU sensitivity of the circuits. Using SPICE simulations, the measured smooth transition of the cross-section curve between LET threshold and saturation has been traced to the presence of four different upset modes, each corresponding to a different critical charge and sensitive area. A new architecture to protect the content of storage cells has been developed, and a threshold LET around 89 MeV cm/sup 2/ mg/sup -1/ has been measured for this cell at a power supply voltage of 2 V

Efecto de la adición de ácido cítrico y la cantidad de yeso sobre las propiedades del cemento de sulfoaluminato de calcio

The influence of citric acid on the hydration and strength development of a calcium sulphoaluminate cement was investigated. Cement pastes were prepared by mixing calcium sulphoaluminate (C4A3Ŝ) with 15, 20 and 25wt% of hemihydrate (CŜH0.5). Citric acid was added as a retarder at 0 and 0.5wt%. The samples were cured at 20 °C for periods of time from 1 to 28 days to evaluate their compressive strength and to characterize the hydration products by scanning electron microscopy and X-ray diffraction. Calorimetric curves showed that the retarding agent considerably decreases the heat release rate and the quantity of total heat released. The main product after the curing was ettringite (C6AŜ3H32). The morphology of this phase consisted of long and thin needles growing radially on the cement grains. Samples with 15wt% of hemihydrate and 0.5wt% of citric acid developed the highest compressive strength (70 MPa) at 28 days of curing.Se investigó el efecto del ácido cítrico sobre la hidratación y propiedades mecánicas de un cemento de sulfoaluminato de calcio. El C4A3Ŝ se mezcló con 15, 20 y 25% e.p. de hemihidrato (CŜH0.5). Se agregó ácido cítrico como retardante en 0 y 0.5% e.p. Las muestras fueron curadas a 20 °C por periodos de 1 a 28 días para realizar mediciones de resistencia a la compresión y caracterizar los productos de hidratación mediante microscopía electrónica de barrido y difracción de rayos X. Las curvas de calorimetría mostraron ue el ácido cítrico disminuye la velocidad de liberación de calor y la cantidad de calor liberado durante la hidratación. La resistencia a la compresión alcanzó un máximo de 70 MPa en muestras con 15% e.p. de hemihidrato y 0,5% e.p de ácido cítrico. Los resultados muestran a la etringita (C6AŜ3H32) como principal producto de hidratación. Se observa a esta fase con morfología acicular creciendo sobre las partículas de cemento

Efecto del contenido de aluminato de estroncio y hemihidrato sobre las propiedades de un cemento de sulfoaluminato de calcio

The effect of strontium aluminate (SrAl2O4) on the hydration process of a calcium sulphoaluminate (C4A3Ŝ) cement was investigated. Cement pastes were prepared by mixing C4A3Ŝ , hemihydrate (CaSO4· ½H2O, CŜH0.5) and 0, 10 or 20wt% of SrAl2O4 (SrA). The amount of CŜH0.5 was 15, 20 or 25wt% based on the C4A3Ŝ quantity. The cement pastes were hydrated using water to cement ratios (w/c) of 0.4 and 0.5. Samples were cured from 1 to 28 d. The compressive strength and setting time were evaluated and the hydration products were characterized. It was found that the setting time was delayed up to 42 min for the samples containing SrAl2O4 compared to samples without addition. The samples with 25wt% hemihydrate containing 20wt% SrAl2O4 developed the highest compressive strength (60 MPa) after 28 d of curing. The main product after hydration was ettringite (C6AŜ3H32). The morphology of this phase consisted of thin needle-shaped crystals.Se investigó el efecto de la adición de aluminato de estroncio (SrAl2O4) sobre las propiedades de un cemento de sulfoaluminato de calcio (C4A3Ŝ). Se prepararon muestras mezclando C4A3Ŝ, hemihidrato (CaSO4· ½H2O, CŜH0.5) y 0, 10 o 20% e.p de SrAl2O4 (SrA). La cantidad de CŜH0.5 fue de 15, 20 o 25% e.p. basado en la cantidad de C4A3Ŝ. Las relaciones agua/cemento utilizadas fueron 0.4 y 0.5. Las muestras fueron curadas hasta 28 d. Se evaluó el tiempo de fraguado y la resistencia a la compresión. Los productos de hidratación se caracterizaron mediante DRX y MEB. El tiempo de fraguado se retardó hasta 42 minutos con la adición del SrAl2O4 comparado con las muestras sin adiciones. Las muestras con 25% e.p. de yeso y 20% e.p. de SrAl2O4 desarrollaron la mayor resistencia a la compresión alcanzando 60 MPa a 28 d de curado. Los análisis por MEB y DRX muestran como principal producto de hidratación a la etringita (C6AŜ3H32), cuya morfología se observa como cristales aciculares