Photosynthetic Rate of Lettuce Cultivated on Floating Raft Hydroponic with Controlled Nutrient Solution

Lettuce becomes the main ingredient of salad as one of the healthy foods. The lettuce cultivation in tropical areas is often performed in highland. To reduce soil erosion and pesticide contamination, the cultivation of lettuce plants in high open land needs to be reduced. The lettuce cultivation in hydroponic system at tropical lowland requires cooling. The root zone cooling requires enormous electrical energy. However, it can be solved by controlling the temperature based on the automatically. Therefore, it has been developed control and monitoring system for the root zone on floating raft hydroponic system. This study aimed to evaluate the photosynthetic rate of lettuce cultivated in floating raft hydroponic system whose nutrient solution was controlled by the developed control and monitoring system. Statistical analysis was performed to draw the conclusions about photosynthetic variance of lettuce on two hydroponic systems, namely controlled and uncontrolled system. Furthermore, this paper presents an artificial neural network (ANN) model to estimate the photosynthetic rate of lettuce cultivated in the hydroponic systems. The ANN model was comprised of eight input (nutrient temperature, EC, pH, DO, and ORP, air temperature, air humidity, and photon flux density of photosynthetic) and one output (photosynthetic rate). It was noted that the ANN model predicted accurately the photosynthetic rate of lettuce leaves whose R2 was 0.87 for plants cultivated in floating raft hydroponic system whose nutrient solution was controlled by control and monitoring system. The ANN was useful for identifying the photosynthetic rate of lettuce cultivated in floating raft hydroponic systems on tropical lowland

Studies of cosmic-ray solar modulation with the PAMELA experiment

The launch of the satellite-borne PAMELA instrument on the 15th June 2006 opened a new era of high-precision studies of cosmic rays. Due to its low detection energy threshold and its long operation, PAMELA was able to accurately measure the fluxes of several cosmic-ray species over a large energy range and study their time variations below a few tens of GeVs. In this presentation we will review PAMELA results on the time-dependent proton, helium and electron fluxes measured between a few tens of MeV/n and few tens of GeV/n from 2006 to 2014. Moreover, preliminary results of yearly energy spectra of deuterons, helium-3 and helium-4 nuclei below 1 GeV/n will be discussed. These measurements covered a time including the minimum phase of the 23rd solar cycle and the 24th solar maximum including the polarity reversal of the solar magnetic field. The PAMELA measurements have allowed to significantly improve the understanding of the charged-particle propagation through the Heliosphere, the charge-sign effect due to the drift motions of these particles and to calibrate state-of-the-art models of cosmic-ray transport in the Heliosphere

Cosmic Antihelium Nuclei Sensitivity of the GAPS Experiment

The General Antiparticle Spectrometer (GAPS) is an Antarctic balloon experiment designed for low-energy (0.1$-$0.3 GeV/$n$) cosmic antinuclei as signatures of dark matter annihilation or decay. GAPS is optimized to detect low-energy antideuterons, as well as to provide unprecedented sensitivity to low-energy antiprotons and antihelium nuclei. The novel GAPS antiparticle detection technique, based on the formation, decay, and annihilation of exotic atoms, provides greater identification power for these low-energy antinuclei than previous magnetic spectrometer experiments. This work reports the sensitivity of GAPS to detect antihelium-3 nuclei, based on full instrument simulation, event reconstruction, and realistic atmospheric influence simulations. The report of antihelium nuclei candidate events by AMS-02 has generated considerable interest in antihelium nuclei as probes of dark matter and other beyond the Standard Model theories. GAPS is in a unique position to detect or set upper limits on the cosmic antihelium nuclei flux in an energy range that is essentially free of astrophysical background. In three long-duration balloon flights, GAPS will be sensitive to an antihelium flux on the level of $1.3^{+4.5}_{-1.2}\cdot 10^{-6}\mathrm{m^{-2}sr^{-1}s^{-1}}(\mathrm{GeV}/n)^{-1}$ (95% CL) in the energy range of 0.11$-$0.3 GeV/$n$, opening a new window on rare cosmic physics.Comment: 12 pages, 5 figure

Maternal Risk of Breeding Failure Remained Low throughout the Demographic Transitions in Fertility and Age at First Reproduction in Finland

Radical declines in fertility and postponement of first reproduction during the recent human demographic transitions have posed a challenge to interpreting human behaviour in evolutionary terms. This challenge has stemmed from insufficient evolutionary insight into individual reproductive decision-making and the rarity of datasets recording individual long-term reproductive success throughout the transitions. We use such data from about 2,000 Finnish mothers (first births: 1880s to 1970s) to show that changes in the maternal risk of breeding failure (no offspring raised to adulthood) underlay shifts in both fertility and first reproduction. With steady improvements in offspring survival, the expected fertility required to satisfy a low risk of breeding failure became lower and observed maternal fertility subsequently declined through an earlier age at last reproduction. Postponement of the age at first reproduction began when this risk approximated zero–even for mothers starting reproduction late. Interestingly, despite vastly differing fertility rates at different stages of the transitions, the number of offspring successfully raised to breeding per mother remained relatively constant over the period. Our results stress the importance of assessing the long-term success of reproductive strategies by including measures of offspring quality and suggest that avoidance of breeding failure may explain several key features of recent life-history shifts in industrialized societies

East–West Proton Flux Anisotropy Observed with the PAMELA Mission

Abstract We present a study of the east–west anisotropy of trapped-proton fluxes in low-Earth orbit based on the measurements of the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) experiment. The differential intensities of eastward- and westward-traveling protons detected in the South Atlantic Anomaly region were estimated as a function of equatorial pitch angle and drift shell, for six energy bins between 80 MeV and 2 GeV. We found that, as a consequence of the strong atmospheric gradient coupled with the large gyroradius in this energy range, the intensities of eastward fluxes exceed those of westward fluxes by a factor of ∼10–20. However, the reported directional asymmetry also depends on the sign of the local flux gradient, resulting in more intense westward fluxes beyond the radial distances where the inner belt peaks. PAMELA observations can be used to improve the description of the near-Earth radiation environment at lowest altitudes and highest trapping energies, where current theoretical and empirical models are affected by the largest uncertainties