SWINE WASTE PHYTOREMEDIATION USING DUCKWEED (Landoltia punctata, Les & Crawford) IN A FULL SCALE PLANT

Banner Apresentado em Congresso: 11th International Conference, Heraklion, Crete, Greece PhytotechnologiesThe large amount of nitrogen and phosphorous compounds found in pig manure has caused ecological imbalances, with eutrophication of major river basins in the producing regions. Therefore, the aquatic macrophytes group named duckweeds (Araceae; Lemnoideae) have been successfully used for phytoextraction and rhizodegradation of nutrient and heavy metals from swine waste, generating further a biomass with high protein content. The present study evaluated the phytoremediation of nitrogen and phosphorus from swine waste using the duckweed Landoltia punctata and also their protein biomass production as by-product

Using full-scale duckweed ponds as the finish stage for swine waste treatment with a focus on organic matter degradation

Artigo Publicado em: IWA - Water Science & TechnologyThe rapid increase in the number of swine has caused pronounced environmental impacts worldwide, especially on water resources. As an aggregate, smallholdings have an important role in South American pork production, contributing to the net diffusion of pollution. Thus, duckweed ponds have been successfully used for swine waste polishing, mainly for nutrient removal. Few studies have been carried out to assess organic matter degradation in duckweed ponds. Hence, the present study evaluated the efficiency of two full-scale duckweed ponds for organic matter reduction of swine waste on small pig farms. Duckweed ponds, in series, received the effluent after an anaerobic biodigester and storage pond, with a flow rate of 1 m3 day 1. After 1 year of monitoring, an improvement in effluent quality was observed, with a reduction in biochemical oxygen demand (BOD) and total chemical oxygen demand (tCOD), respectively, of 94.8 and 96.7%, operating at a loading rate of approximately 27 kgBOD ha 1 day 1 and 131 kgCOD ha 1 day 1. Algae inhibition due to duckweed coverage was strongly observed in the pond effluent, where chlorophyll a and turbidity remained below 25 μg L 1 and 10 NTU. Using the study conditions described herein, duckweed ponds were shown to be a suitable technology for swine waste treatment, contributing to the environmental sustainability of rural areas

Revealing hidden symmetries and gauge invariance of the massive Carroll-Field-Jackiw model

In this paper we have analyzed the improved version of the Gauge Unfixing (GU) formalism of the massive Carroll-Field-Jackiw model, which breaks both the Lorentz and gauge invariances, to disclose hidden symmetries to obtain gauge invariance, the key stone of the Standard Model. In this process, as usual, we have converted this second-class system into a first-class one and we have obtained two gauge invariant models. We have verified that the Poisson brackets involving the gauge invariant variables, obtained through the GU formalism, coincide with the Dirac brackets between the original second-class variables of the phase space. Finally, we have obtained two gauge invariant Lagrangians where one of them represents the Stueckelberg form.Comment: revised version. To appear in Europhysics Letter

It comes from the sea: macroalgae-derived bioactive compounds with anti-cancer potential

Nature derived compounds represent a valuable source of bioactive molecules with enormous potential. The sea is one of the richest environments, full of skilled organisms, where algae stand out due to their unique characteristics. Marine macroalgae adapt their phenotypic characteristics, such as chemical composition, depending on the environmental conditions where they live. The compounds produced by these organisms show tremendous potential to be used in the biomedical field, due to their antioxidant, anti-inflammatory, immunomodulatory, and anti-cancer properties. Cancer is one of the deadliest diseases in the world, and the lack of effective treatments highlights the urgent need for the development of new therapeutic strategies. This review provides an overview of the current advances regarding the anti-cancer activity of the three major groups of marine macroalgae, i.e., red algae (Rhodophyta), brown algae (Phaeophyceae), and green algae (Chlorophyta) on pancreatic, lung, breast, cervical, colorectal, liver, and gastric cancers as well as leukemia and melanoma. In addition, future perspectives, and limitations regarding this field of work are also discussed.info:eu-repo/semantics/publishedVersio

Learning 2-opt Heuristics for the Traveling Salesman Problem via Deep Reinforcement Learning

Recent works using deep learning to solve the Traveling Salesman Problem (TSP) have focused on learning construction heuristics. Such approaches find TSP solutions of good quality but require additional procedures such as beam search and sampling to improve solutions and achieve state-of-the-art performance. However, few studies have focused on improvement heuristics, where a given solution is improved until reaching a near-optimal one. In this work, we propose to learn a local search heuristic based on 2-opt operators via deep reinforcement learning. We propose a policy gradient algorithm to learn a stochastic policy that selects 2-opt operations given a current solution. Moreover, we introduce a policy neural network that leverages a pointing attention mechanism, which unlike previous works, can be easily extended to more general k-opt moves. Our results show that the learned policies can improve even over random initial solutions and approach near-optimal solutions at a faster rate than previous state-of-the-art deep learning methods.Comment: To appear in Proceedings Machine Learning Research - ACML 202