Reconfigurable unitary transformations of optical beam arrays.

Spatial transformations of light are ubiquitous in optics, with examples ranging from simple imaging with a lens to quantum and classical information processing in waveguide meshes. Multi-plane light converter (MPLC) systems have emerged as a platform that promises completely general spatial transformations, i.e.

Towards quantum telescopes: demonstration of a two-photon interferometer for precision astrometry.

Classical optical interferometry requires maintaining live, phase-stable links between telescope stations. This requirement greatly adds to the cost of extending to long baseline separations and limits on baselines will in turn limit the achievable angular resolution. Here we describe a novel type of two-photon interferometer for astrometry, which uses photons from two separate sky sources and does not require an optical link between stations.

Sugarcane production and climate trends in Paraíba state (Brazil).

Statistical surveys to detect trends in time series are fundamental tools to evaluate farming dynamics of sugarcane and of adaptation plans for possible impacts caused by climate change. This work analyzed the influence of climate change in the cultivation of sugarcane in the state of Paraíba (Northeast Brazil), in order to investigate what are the consequences of temperature increase, air humidity level, and changes in the precipitation regime forecasted for the region in sugarcane farming. Data of temperature, total precipitation, and relative humidity of six meteorological stations kept by the Brazilian National Institute of Meteorology (INMET) spread across the state of Paraíba and data from the area of sugarcane harvesting from the Brazilian Institute of Geography and Statistics (IBGE).

Comparison between observed and estimated data to assess air temperature variability and trends in the Sertão Paraibano mesoregion (Brazil).

Given the importance of climate for society at different scales, such as local, regional, and global scales, the analysis of trends of climatic elements improves the assessment of projections and variations, aiding in the design of policies focused on processes of adaptation to and mitigation of the effects of climate change. The aim of this study was to detect mean air temperature trends in the Sertão Paraibano mesoregion in Brazil by constructing temperature series with observed data provided by the Brazilian National Institute of Meteorology (INMET) collected in the localities of Patos and São Gonçalo and with data estimated using Estima_T software to study the spatial and temporal distribution of the mean air temperature of seven localities in the Sertão Paraibano mesoregion: Água Branca, Aguiar, Coremas, Patos, Princesa Isabel, São Gonçalo, and Teixeira. The temperature series with observed and estimated data were compared, showing the variability of using temperature estimates to overcome the lack of meteorological stations in the study area.

Effectiveness of nutrient remotion and cell physiology of Amphora sp. cultured in shrimp farm effluents.

Shrimp farm effluents are one of the principal causes of eutrophication in coastal environments. Integrated processes of bioremediation involving the culturing of purifying organisms have been suggested, but very few studies have focused on microalgae. For that purpose evaluated the growth potential of Amphora sp.

Environmental evaluation of the life cycle of elephant grass fertilization-Cenchrus purpureus (Schumach.) Morrone-using chemical fertilization and biosolids.

Law 12305/10, National Solid Waste Policy of Brazil, banned the disposal in landfills of any solid waste that could be converted to another use. Sludge produced at Industrial Wastewater Treatment Plants, which contains components characteristic of fertilizers, falls into this category. This type of sludge, also known as a biosolid, has great potential to replace commercial chemical fertilization.

Cultivation of freshwater microalgae in biodiesel wash water.

Biodiesel wash water is a contaminating industrial effluent that must be treated prior to disposal. The use of this effluent as a low-cost alternative cultivation medium for microalgae could represent a viable supplementary treatment. We cultivated 11 microalgae species with potential use for biodiesel production to assess their growth capacities in biodiesel industrial washing waters.

Carbon and water footprints of irrigated corn and non-irrigated wheat in Northeast Spain.

Irrigation increases yields and allows several crops to be produced in regions where it would be naturally impossible due to limited rainfall. However, irrigation can cause several negative environmental impacts, and it is important to understand these in depth for the correct application of mitigation measures. The life cycle assessment methodology was applied herein to compare the main irrigated and non-irrigated crops in Northeast Spain (corn and wheat, respectively), identifying those processes with greater contribution to environmental impacts (carbon and water footprint categories) and providing scientifically-sound information to facilitate government decisions.

Life cycle assessment of the transesterification double step process for biodiesel production from refined soybean oil in Brazil.

Biodiesel has been attracting considerable attention as being a renewable, biodegradable, and nontoxic fuel that can contribute to the solution of some energy issues as it presents potential to help mitigate climate change. The Life Cycle Assessment of biodiesel from soybean oil (transesterification double step process) was carried out herein. A pilot plant was considered, designed to produce 72 L of biodiesel in daily continuous flow, throughout a lifetime of 15 years (8000 annual hours).

Climate change and the water cycle in newly irrigated areas.

Climate change is affecting agriculture doubly: evapotranspiration is increasing due to increments in temperature while the availability of water resources is decreasing. Furthermore, irrigated areas are expanding worldwide. In this study, the dynamics of climate change impacts on the water cycle of a newly irrigated watershed are studied through the calculation of soil water balances.

Nitrate and salt water contamination associated with the transition of an agrarian basin into an irrigated area.

The introduction of irrigation to agrarian areas involves several environmental changes that can be aggravated by physical and agronomic factors. The aim of this study is to analyze the spatiotemporal dynamics of the environmental impact on water resources that result from the transition of an agrarian basin into an irrigated area. During five hydrological years, a spatiotemporal comparison was carried out on the quantity and quality of drainage from the four zones in which the study area was subdivided.