Strategies to Modulate Specialized Metabolism in Mediterranean Crops: From Molecular Aspects to Field

Plant specialized metabolites (SMs) play an important role in the interaction with the environment and are part of the plant defense response. These natural products are volatile, semi-volatile and non-volatile compounds produced from common building blocks deriving from primary metabolic pathways and rapidly evolved to allow a better adaptation of plants to environmental cues. Specialized metabolites include terpenes, flavonoids, alkaloids, glucosinolates, tannins, resins, etc. that can be used as phytochemicals, food additives, flavoring agents and pharmaceutical compounds. This review will be focused on Mediterranean crop plants as a source of SMs, with a special attention on the strategies that can be used to modulate their production, including abiotic stresses, interaction with beneficial soil microorganisms and novel genetic approaches.     

Phytoextraction technologies for mercury- and chromium-contaminated soil: a review

Mercury and chromium represent two important elements of environmental concern and with a strong impact on human health. Several technologies are available to clean up the environment from these kinds of contaminants, but most of them are costly and difficult to use to get optimum results. Currently, phytoextraction is an effective and affordable technological solution used to extract or remove metals from contaminated soil and water by the use of plants as tools. This technology is environment-friendly and potentially cost-effective. This paper aims to compile some information about the two metals mercury and chromium, their effects and their possible treatment by phytoextraction, a branch of phytoremediation technologies aimed to confront metal/metalloid pollution. © 2019 Society of Chemical Industry     

Simulated annealing-based fitting of CAD models to point clouds of mechanical parts’ assemblies

Engineering with Computers - This paper introduces a new fitting approach to allow an efficient part-by-part reconstruction or update of editable CAD models fitting the point cloud of a digitized...     

Tuning light emission of PbS nanocrystals from infrared to visible range by cation exchange

Colloidal semiconductor nanocrystals, with intense and sharp-line emission between red and near-infrared spectral regions, are of great interest for optoelectronic and bio-imaging applications. The growth of an inorganic passivation layer on nanocrystal surfaces is a common strategy to improve their chemical and optical stability and their photoluminescence quantum yield. In particular, cation exchange is a suitable approach for shell growth at the expense of the nanocrystal core size. Here, the cation exchange process is used to promote the formation of a CdS passivation layer on the surface of very small PbS nanocrystals (2.3 nm in diameter), blue shifting their optical spectra and yielding luminescent and stable nanostructures emitting in the range of 700–850 nm. Structural, morphological and compositional investigation confirms the nanocrystal size contraction after the cation-exchange process, while the PbS rock-salt crystalline phase is retained. Absorption and photoluminescence spectroscopy demonstrate the growth of a passivation layer with a decrease of the PbS core size, as inferred by the blue-shift of the excitonic peaks. The surface passivation strongly increases the photoluminescence intensity and the excited state lifetime. In addition, the nanocrystals reveal increased stability against oxidation over time. Thanks to their absorption and emission spectral range and the slow recombination dynamics, such highly luminescent nano-objects can find interesting applications in sensitized photovoltaic cells and light-emitting devices.     

The renewable energy market in Brazil: Current status and potential

Renewable energy offers a range of options with which to meet the growing demand for energy, particularly in the context of the pursuit (especially in developing countries) of economic development which takes into account social and environmental issues. Brazil has abundant natural sources of renewable energy, such as wind and solar power, hydraulic energy, small hydroelectric plants, ethanol and bio-diesel. These sources form part of the Brazilian strategy aimed at satisfying the demand for 6300 MW of fresh capacity per year arising out of projected economic growth of 5.1% per year over the next 10 years. Renewable energy sources currently provide 47.2% of the internal supply of primary energy in Brazil. Brazil has been pursuing a strategy of maintaining its renewable energy matrix and developing and providing incentives for further low carbon initiatives.In this study we set out an overview of the renewable energy options available in Brazil, their current status, the main positive results obtained to date and future potential. We describe the market for renewable energy in Brazil and examine specific public policies aimed at overcoming barriers to this market, thereby promoting its consolidation and expansion.     

MOSFET threshold voltage: Definition,extraction, and some applications

This paper exploits a universal current-based definition of the threshold voltage (V_T) and discusses some direct methods to measure it. The consistency, accuracy, and sensitivity of the extraction procedures to second-order effects are examined through numerical simulations and experimental measurements. In addition to three procedures based on dc current measurements we propose an automatic V_T-extractor circuit which allows the direct determination of the threshold voltage with minimum influence of second-order effects.     

A real time FFT-based impedance meter with bias compensation

A real time FFT-based impedance meter is here presented. It is realized simply by a standard PC in addition to a low cost two channels hardware device, and is based on a cost-effective algorithm to meaningfully reduce the known problem of the bias introduced by the relative phase and amplitude error between channels. The impedance meter exploits the implementation of an ad hoc cost-effective algorithm and a synchronous sampling allows eliminating the leakage error. The aliasing and the spectral interference are eliminated by means of an anti-aliasing filter and the use of very low distortion sinusoidal signals. Automatic measurements can be managed too, capturing different measures at different test frequencies and displaying them graphically on the PC screen. To validate the measured results comparative test were performed with respect to certified and calibrated commercially available multimeters known with good accuracies.Finally, this novel impedance meter integrates a home-made software, previously reported [1] capable to implement real time virtual instruments.     

Evaluation of the impact of access to electricity: A comparative analysis of South Africa,China, India and Brazil

Most developing countries include rural electrification programs in their efforts to improve social conditions. There are, however, several obstacles to the evaluation of such programs and therefore of their social, economic, environmental and energy impacts on the target population, particularly on impoverished communities located in remote areas. Evaluation of the efficacy of public policies aimed at rural electrification in South Africa, China, India and Brazil enables such actions to be quantified and re-considered so as to bolster the sustainability of their planning and implementation and also so as to enable comprehension of the significance of access to electricity in relation to other aspects of the drive to improve living standards. The provision of electric energy amounts to more than access to a public service and should be considered an essential right, in a context of social equity and justice, which permits social integration and the access to other equally essential services.