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Soil degradation and climate change are threatening the sustainability of Mediterranean olive orchards, typically grown under rainfed conditions and conventional soil tillage. Thus, implementing sustainable soil management practices is crucial to preserve soil health and mitigate the negative effects on plant performance. In this study, we assessed the effects of conventional tillage (T), an early maturing and self-reseeding annual legume cover crop (LC) and its combination with natural zeolites (ZL) on plant physiological performance, tree nutritional status, crop yield, and soil physicochemical and microbiological properties. Although both LC and ZL enhanced the photosynthetic activity, tree nutritional status, soil moisture and olive yield relative to T, ZL was clearly more efficient at improving some soil health indicators, namely at the 0–10 cm soil layer, once soil acidity decreased and Kjeldahl N, extractable P and B, cation exchange capacity and microbiological activity increased, as evidenced by the higher concentrations of easily extractable and total glomalin-related soil protein, microbial biomass carbon, microbial biomass quotient, and actinomycetes. Therefore, using natural zeolite with leguminous cover crops appears to be a promising strategy of sustainable soil management in rainfed olive orchards, as it is able to provide numerous ecosystem services. [ABSTRACT FROM AUTHOR]

Under climate change threats, there is a growing need to adapt the conventional agronomic practices used in rainfed olive orchards by sustainable practices, in order to ensure adequate crop yield and olive oil quality and to preserve soil health. Therefore, for two years, the effects of conventional tillage practice (T) and two sustainable soil management strategies, a leguminous cover crop (LC) and its combination with natural zeolites (ZL), on the yield, fatty acid composition, polyphenolic profile and quality indices of olive fruits and oil were evaluated. Crop yield was significantly increased by LC and ZL in the first year. Although in the second year no significant differences were verified, the cumulative yield increased significantly by 31.6% and 35.5% in LC and ZL trees, respectively. LC enhanced the moisture and size of olives, while ZL increased, in general, the concentrations of oleuropein, verbascoside, caffeic acid and epicatechin, as well the oleic/linoleic ratio in fruits and the levels of 3,4-dihydroxyphenylglycol, tyrosol, verbascoside and caffeic acid in olive oil. Despite the higher concentration of total phenols in the fruits and oil from T trees in the warmer and dryer year, the quality of the oil decreased, mainly when compared with ZL, as evidenced by the peroxide value and K232 and K270 coefficients. In short, both sustainable soil management strategies appear to be promising practices to implement in olive orchards under rainfed conditions, but the innovative strategy of combining zeolites with legume cover crops, first reported in the present study, confers advantages from a nutritional and technological point of view. Nevertheless, studies subjected to the long-term use of these practices should be conducted to ensure the sustainability of the crop yield and olive oil quality. [ABSTRACT FROM AUTHOR]

The effects of mineral fertilizers on the physicochemical properties of olives and oil under rainfed conditions is scarce. In this three-year study, the results of a nitrogen (N), phosphorus (P), potassium (K) and boron (B) fertilization trial carried out in a young rainfed olive grove and arranged as a nutrient omission trial are reported. The control consisted of the application of N, P, K and B (NPKB) and four other treatments corresponded to the removal of one of them (N0, P0, K0 and B0). Olive yield and several variables associated with the physicochemical properties of olives and oil were evaluated. The NPKB treatment increased olive yield compared to the treatment that did not receive N (N0). Although dependent on the climate conditions of the crop season, the NPKB treatment increased fruit weight and the pulp/pit ratio and its fruits tended to accumulate more oil than K0. However, the phenolics concentrations on fruits and oil tended to be lower. All olive oil samples were classified in the "extra virgin" category and all showed a decrease in its stability between 3 and 15 months of storage, regardless of treatment, especially in N0, P0 and B0 treatments. The results of the sensorial analysis indicate that all the oils fell into the medium fruitiness and greenly-fruity category. Only in P0 and B0 were defects detected, namely muddy sediment. Thus, this study seems to indicate the importance of N application, but also a balanced nutrient application and that further studies are needed, given the difficulty in finding clear trends in the response of measured variables to fertilizer treatments. [ABSTRACT FROM AUTHOR]

Throughout the past decade, the advanced telecommunications computing architecture (ATCA) solidified its position as one of the main switched-based crate standards for advanced physics instrumentation, offering not only high performance characteristics in data throughput, channel density, or power supply/dissipation capabilities but also special features for high availability (HA), required for the latest and upcoming large-scale endeavors, as is the case of ITER. Hot swap is one of the main HA features in ATCA, allowing for boards to be replaced in a crate (shelf), without powering off the whole system. Platforms using the peripheral component interconnect express (PCIe) protocol on the fabric interface must be complemented, at the software level, with the PCIe hot-plug native feature, currently not specified for the ATCA form-factor. From a customized hot-plug support implementation for ATCA node boards, this article presents an implementation extension for hub boards, allowing hot-plug of PCIe switching devices, without causing bus enumeration problems. This article further addresses the main issues concerning an eventual standardization of PCIe hot-plug support in ATCA, such as the implementability of hot-plug elements and the generation and management of hot-plug events, aiming to stimulate the discussion within the PCI Industrial Computer Manufacturers Group (PICMG) community toward a long-overdue standardized solution for hot-plug in ATCA. [ABSTRACT FROM AUTHOR]

Different SA concentrations (10, 100 and 1000 μM) were applied in young olive trees (Olea europaea L.) subjected to drought and rewatering. Plants treated with 10 μM exhibited a close behavior to SA-starved plants. Although both 100 and 1000 μM improved the balance between ROS production and scavenging, 100 μM was more efficient. During drought, 100 μM improved ROS detoxification and scavenging by the maintenance or overaccumulation of soluble proteins. During recovery, soluble proteins return to well-watered values and increased the investment in non-enzymatic antioxidants. 100 μM was also the most effective in plant ionome regulation, improving macro and micronutrients uptake, namely P, Fe, Mn and Zn, and changing mineral allocation patterns. Therefore, 100 μM also countered the drought-induced decline in total plant biomass accumulation. The application of suitable SA concentrations is an efficient tool to improve cellular homeostasis and growth of plants subjected to recurrent drought episodes. • Salicylic acid (SA) influence in young olive trees is concentration dependent. • 100 μM SA ameliorates olive tree responses to recurrent drought episodes. • SA improves the balance between ROS production and scavenging. • SA improves plant ionome regulation. • SA promotes root development. [ABSTRACT FROM AUTHOR]

The main role of the ITER Radial Neutron Camera (RNC) diagnostic is to measure in real time the plasma neutron emissivity profile at high peak count rates for a time duration up to 500 s. Due to the unprecedented high-performance conditions and after the identification of critical problems, a set of activities have been selected, focused on the development of high-priority prototypes, and capable to deliver answers to those problems before the final RNC design. This paper presents one of the selected activities: the design, development, and testing of a dedicated field-programmable gate array (FPGA) code for the RNC data acquisition prototype. The FPGA code aims to acquire, process, and store in real time the neutron and gamma pulses from the detectors located in collimated lines of sight (LOS) viewing a poloidal plasma section from the ITER Equatorial Port Plug 1. The hardware platform used was an evaluation board from Xilinx (KC705) carrying an IPFN FPGA Mezzanine Card (FMC-AD2-1600) with two digitizer channels of 12-bit resolution sampling up to 1.6 Gsamples/s. The code performs the proper input signal conditioning using a down-sampled configuration to 400 Msamples/s, applies dedicated algorithms for pulse detection, filtering and pile up (PU) detection, and includes two distinct data paths operating simultaneously: 1) the event-based datapath for pulse storage and 2) the real-time processing with dedicated algorithms for pulse shape discrimination (PDS) and pulse height spectra (PHS). For continuous data throughput, both datapaths are streamed to the host through two distinct PCIe $\times 8$ direct memory access (DMA) channels. [ABSTRACT FROM AUTHOR]

Highlights • UV-A and UV-B can be used to modulate the tomato fruit quality. • UV-A supplementation increases the concentration of antioxidant compounds in fruits. • The UV-A doses tested here are more promising than UV-B. Abstract Solanum lycopersicum L. is among the healthiest fruits/vegetables due to its richness in bioactive compounds. However, its fruits from off-season (usually obtained in greenhouses that block UV-rays) have lower reputation than the ones of in-season/field productions. We hypothesise that moderate UV-A/UV-B irradiation during fruit development is able to improve its bioactive compounds and sensorial attributes, increasing its healthy properties. We supplemented for 30 days 'MicroTom' fruiting plants with two daily doses of UV-A (1 or 4 h) and UV-B (2 or 5 min). Irradiated plants showed higher ripening synchronization and produced more and smaller fruits. UV-A irradiation stimulated the fruit's antioxidant capacity, and the antiradical activity by the accumulation of phenolic compounds including the flavonoids. Only the UV-A1 h condition promoted the accumulation of ortho-diphenols in tomato fruits. Regarding the consumers' preference for aroma/taste, a consumers' panel test ranked the tomatoes as UV-A 1 h, UVA 4 h, Control, UV-B 5 min and UV-B 2 min. We conclude that the supplementation of UV-A during pre-harvest is particularly effective in increasing ripening synchronization and fruit's nutritional properties, potentially making these fruits more appealing to consumers. [ABSTRACT FROM AUTHOR]

Highlights • Kaolin (KL) and salicylic acid (SA) alleviate summer stress effects on olive trees. • KL and SA modulate distinct physiological and biochemical responses. • KL reduce the plant necessity to invest in extra protective mechanisms. • SA improve some stress tolerance responses. • KL and SA improved trees recovery during stress relief. Abstract In a changing world, the search for new agronomic practices that help crops to maintain and/or increase yields and quality is a continuous challenge. We aim to evaluate kaolin (KL) and salicylic acid (SA) effectiveness as summer stress alleviating agents through physiological, biochemical and immunohistochemical analysis. Olive trees (Olea europaea L. cv. Cobrançosa) grown under rainfed conditions were sprayed with 5% KL and 100 μM SA, at the beginning of summer, during two consecutive years. KL enhanced relative water content (RWC), stomatal conductance (g s) net photosynthesis (A) and leaf indole-3-acetic acid (IAA) signal, and decreased leaf sclerophylly, secondary metabolites and non-structural carbohydrates accumulation and abscisic acid (ABA).The trees treated with SA showed changes on IAA and ABA dynamics, and an enhancement in RWC, g s , A, soluble proteins, and leaf P and Mg concentrations during the summer. Notably, KL and SA also allowed a faster restauration of the physiological functions during stress relief. In sum, KL and SA foliar sprays alleviated the negative effects induced by summer stress in olive trees performance, by modulation of distinct physiological and biochemical responses. [ABSTRACT FROM AUTHOR]

Abstract Regarding the foreseeing climate change is reasonable to expect harmful consequences to olive tree (Olea europaea L.), an iconic species of Mediterranean region. Thus, the selection of practices that allow a better drought resistance and recovery capacity needs the immediate attention of scientific community. This study evaluates the strategies adopted by young potted olive trees, subjected to three cycles of drought and rewatering, in the presence of a reflective clay, kaolin (KL). The results demonstrated that KL induced shade-related leaf structural changes and was effective in keeping leaf water status during the most stressful periods. In general, photosynthetic activity of sprayed plants was improved by the alleviation of drought-induced stomatal and non-stomatal limitations. Moreover, during stress imposition sprayed leaves showed reduced oxidative damages, allowing lower investment in antioxidant defences. Furthermore, sprayed plants also had lower nighttime water losses due to inferior nighttime stomatal conductance, and are able to maintain higher respiration rates. Upon rewatering, the shaded effect conferred by KL limited gas exchange restauration, but improved the plants' capacity to restore the metabolic functions. In spite of the induced physiological and biochemical changes, no significant differences were found in whole-plant water use efficiency and plant biomass accumulation, possibly by the attenuation of photosynthesis restauration during the recovery events. In conclusion, the changes induced by KL might be beneficial under severe conditions, as on realistic Mediterranean field environments. Highlights • Kaolin (KL) induces shade-related leaf characteristics. • KL improves water status and reduces nighttime water losses during drought. • KL improves photosynthetic capacity and reduces oxidative damages during drought. • KL limits gas exchange restauration after stress relief. • KL improves the capacity to restore the metabolic functions upon rewatering. [ABSTRACT FROM AUTHOR]

Highlights: [•] Elevated CO2 enhanced carbon accumulation in rice during its entire life cycle. [•] However, plants grown at elevated CO2 had low levels of phenolic compounds. [•] At maturity, elevated CO2 increased the concentrations of phenolic compounds in rice. [•] Following acclimation of photosynthesis, phenolics were increased by elevated CO2. [•] Following a disease attack, levels of phenolics were also increased by elevated CO2. [Copyright &y& Elsevier]

Extreme climate change events, such as long periods of drought and heat waves, are predicted to increase throughout this century. Pinus species are important economic resources. However, it remains unknown the vulnerability of most species to climate change-related stresses. We aimed to compare the performance reconfiguration of two resin/timber important species [ Pinus elliottii var. elliottii (PE) and the hybrid Pinus elliottii var. elliottii × Pinus caribaea var. hondurensis (PE × PCH)] to face combined stress of drought+heat. Young PE and PE × PCH plants were grown at optimal conditions, then exposed to water deficit for 5 days, and in the last day of water deficit, plants were additionally exposed to a heat shock. The physiological responses, antioxidant capacity and oxidative stress were evaluated immediately and 5 days (recovery) after drought+heat treatment. Under control conditions, the hybrid displayed higher photosynthetic and biochemical performance (e.g. higher net CO 2 assimilation rate, transpiration rate, photosynthetic pigments and anthocyanins levels, carbohydrates and antioxidant enzyme activities). Immediately after the drought+heat episode, plant water status decreased in both species, as well as the PSII photosynthetic parameters (Ф PSII and F v '/F m '), while non-photochemical quenching increased. However, the gas-exchange parameters of PE and the hybrid responded differently to the combined stress. The hybrid suffered a stronger reduction on the net CO 2 assimilation rate and transpiration rate, and presented higher levels of lipid peroxidation, but with no cell membrane permeability injuries. Principal component analysis supports that the different profile of both species is possibly associated to the stronger antioxidant capacity of PE under stress conditions. Moreover, these differences were still observed during recovery and photosynthesis was re-established totally only in PE. The hybrid clearly demonstrated less ability to restore the gas-exchange in the same period, possibly due to stomata re-opening limitations. The low net CO 2 assimilation rates in the hybrid after stress relief could also result in the necessity to use the starch reserves to maintain TSS pools available for stress recovery. We conclude that the hybrid perform better under control conditions, and the PE seems better prepared to cope with the predictable global climate change scenarios forecast for the next decades. The hybrid is more affected by drought+heat, but is able to keep a photosynthetic performance close to the PE under stress, although less efficient during recovery. • The hybrid has a higher physiological performance under optimal growth conditions. • The PE is better prepared to cope with drought and heat episodes. • The hybrid has less ability to recovery the physiological performance after stress. [ABSTRACT FROM AUTHOR]

• Kaolin (KL) improved olive trees performance under sustained deficit irrigation (SDI). • KL improved photosynthetic efficiency at high light intensity. • KL improved cellular metabolic functions and reduced oxidative damages. • KL increased crop yield, oil yield and oxidative stability of olive oil. Regarding the foreseeing climate change is reasonable to expect harmful consequences to olive tree (Olea europaea L.), an iconic species of Mediterranean basin. In large areas of the Region, the sustained deficit irrigation (SDI) accounts with a reduced amount of water that might not be enough to keep the plant functioning at desirable levels. In this study the use of a reflective clay, kaolin, was evaluated in order to alleviate the negative summer stress effects on olive trees (cv. Cobrançosa) under an SDI system. Kaolin reduced the stomatal and the non-stomatal limitations to photosynthesis at high light intensity, improved plant water status, and decreased the oxidative damages. The amelioration of physiological and metabolic functions and the lower allocation of resources to summer stress tolerance mechanisms, allowed the KL-sprayed trees to increase crop yield, the oil yield and its oxidative stability, with the reduction of peroxide index and K 232. Thus, the application of kaolin had a positive synergistic effect with SDI, especially important for semi-arid areas where water available for irrigation do not cover all the necessities. [ABSTRACT FROM AUTHOR]

• Nitrogen fertilization delayed fruit maturation and the incidence of olive fruit fly. • Nitrogen fertilization had no significant effect on olive anthracnose. • Nitrogen fertilization had no significant effect of olive leaf spot. • Pests and diseases do not seem to be relevant criteria to be taken into account in nitrogen management in olive groves. Pests and diseases can cause significant loss of olive yield and/or justify control measures with pesticides which are harmful to the environment. Several agroecological variables, such as fertilization, can favour or limit the incidence of pests and diseases. However, in olive, few studies exist on the subject than can assist in the implementation of more sustainable phytosanitary measures. In this study the effect of nitrogen fertilization (0, 20, 40 and 120 kg N ha−1) on the incidence of olive fruit fly (Bactrocera oleae), olive leaf spot (Spilocaea oleaginea) and olive anthracnose (Colletotrichum gloeosporioides) was evaluated in two olive orchards of the cultivars 'Cobrançosa' and 'Madural'. The study took place in 2017 and 2018 in Lombo, NE Portugal. Nitrogen fertilization significantly increased olive yield and nitrogen concentrations in plant tissues and induced a delay in fruit maturity. The incidence of the olive fruit fly was significantly lower in the more fertilized treatments of both cultivars. However, 'Madural' showed itself to be more susceptible than 'Cobrançosa' to olive fruit fly. The effect of nitrogen on the reduction of the incidence of the olive fruit fly was attributed to the delay caused in fruit maturation, which might have desynchronized the attractiveness of the fruits for insects to lay their eggs on their flight curve. In contrast, olive leaf spot and olive anthracnose were not influenced by nitrogen fertilization. As a result, nutrient management in olive groves must balance carefully the requirements of economic rationality with environmental preservation, particularly with regard to the harmful relationship between the use of excessive nitrogen rates and several adverse environmental effects. [ABSTRACT FROM AUTHOR]

Capturing high-resolution imagery of the Earth's surface often calls for a telescope of considerable size, even from low Earth orbits (LEOs). A large aperture often requires large and expensive platforms. For instance, achieving a resolution of 1 m at visible wavelengths from LEO typically requires an aperture diameter of at least 30 cm. Additionally, ensuring high revisit times often prompts the use of multiple satellites. In light of these challenges, a small, segmented, deployable CubeSat telescope was recently proposed creating the additional need of phasing the telescope's mirrors. Phasing methods on compact platforms are constrained by the limited volume and power available, excluding solutions that rely on dedicated hardware or demand substantial computational resources. Neural networks (NNs) are known for their computationally efficient inference and reduced onboard requirements. Therefore, we developed a NN-based method to measure co-phasing errors inherent to a deployable telescope. The proposed technique demonstrates its ability to detect phasing errors at the targeted performance level [typically a wavefront error (WFE) below 15 nm RMS for a visible imager operating at the diffraction limit] using a point source. The robustness of the NN method is verified in presence of high-order aberrations or noise and the results are compared against existing state-of-the-art techniques. The developed NN model ensures its feasibility and provides a realistic pathway towards achieving diffraction-limited images.

Soil degradation processes and climate change threaten the sustainability of Mediterranean rainfed olive orchards, with repercussions on crop yield and quality of olives, olive oil and olive by-products. Using soil amendments can enhance soil fertility for sustained environmental quality and plant performance. For two years, we evaluated, under rainfed conditions, the effects of a fertilizer compound (FC) and its combination with zeolites (ZL) and biochar (BC) amendments on soil moisture, yield, fruit and oil polyphenols and quality indices. The polyphenolic composition was strongly influenced by treatments, although no effects were observed on crop yield. ZL improved soil moisture (average increase of 26.3% compared to FC), fruit fatty acid composition (increase of 12.4% in oleic/linoleic ratio in 2018) and oil quality, BC enhanced the concentrations of polyphenols with high nutritional value (average annual increase of 25.6, 84.8 and 11.6% for 3,4-dihydroxyphenylglycol, oleuropein and rutin, respectively). In contrast, olive oil from FC fruits showed the poorest quality, with oxidation and hydrolytic breakdown signals. The applied soil amendments appear to be a promising sustainable strategy to implement in olive rainfed orchards.

UV-B radiation effects on nutrient concentrations in above-ground organs of maize were investigated at silking and maturity at different levels of applied nitrogen under field conditions. The experiment simulated a 20% stratospheric ozone depletion over Portugal. At silking, UV-B increased N, K, Ca, and Zn concentrations, whereas at maturity Ca, Mg, Zn, and Cu increased and N, P and Mn decreased in some plant organs. Generally, at maturity, N, Ca, Cu, and Mn were lower, while P, K, and Zn concentrations in stems and nitrogen-use efficiency (NUE) were higher in N-starved plants. UV-B and N effects on shoot dry biomass were more pronounced than on nutrient concentrations. Nutrient uptake decreased under high UV-B and increased with increasing N application, mainly at maturity harvest. Significant interactions UV-B x N were observed for NUE and for concentration and mass of some elements. For instance, under enhanced UV-B, N, Cu, Zn, and Mn concentrations decreased in leaves, except on N-stressed plants, whereas they were less affected by N nutrition. In order to minimize nutritional, economical, and environmental negative consequences, fertiliser recommendations based on element concentration or yield goals may need to be adjusted.

Leaf-level morphological and structural adaptations to reduce water loss were examined in five olive (Olea europaea L.) tree cultivars (Arbequina, Blanqueta, Cobrançosa, Manzanilla and Negrinha) growing under field conditions with low water availability. Leaf measurements included leaf tissue thickness, stomatal density, leaf area, leaf mass per unit area, density of leaf tissue, relative water content, succulence, water saturation deficit, water content at saturation and cuticular transpiration rate. We found considerable genotypic differences among the cultivars. Negrinha, Manzanilla and Cobrançosa had more morphological and structural leaf adaptations to protect against water loss than the other cultivars. Manzanilla and Negrinha enhanced their sclerophylly by building parenchyma tissues and increasing protective structures like the upper cuticle and both the upper and lower epidermis. Cobrançosa exhibited good protection against water loss through high density of foliar tissue and by thick cuticle and trichome layers. Compared with the Negrinha, Manzanilla and Cobrançosa cultivars, Arbequina leaves had a thinner trichome layer, implying that the leaves were less protected against water loss; however, the development of smaller leaves may reduce water loss at the whole-plant level. Among cultivars, Blanqueta had the largest leaves and some anatomical traits that may lead to high water loss, especially from the adaxial surface. The mechanisms employed by the cultivars to cope with summer stress are discussed at the morpho-structural level.