Transient expression in Nicotiana benthamiana for rapid functional analysis of genes involved in non-photochemical quenching and carotenoid biosynthesis.

Plants must switch rapidly between light harvesting and photoprotection in response to environmental fluctuations in light intensity. This switch can lead to losses in absorbed energy usage, as photoprotective energy dissipation mechanisms can take minutes to hours to fully relax. One possible way to improve photosynthesis is to engineer these energy dissipation mechanisms (measured as non-photochemical quenching of chlorophyll a fluorescence, NPQ) to induce and relax more quickly, resulting in smaller losses under dynamic light conditions. Previous studies aimed at understanding the enzymes involved in the regulation of NPQ have relied primarily on labor-intensive and time-consuming generation of stable transgenic lines and mutant populations - approaches limited to organisms amenable to genetic manipulation and mapping. To enable rapid functional testing of NPQ-related genes from diverse organisms, we performed Agrobacterium tumefaciens-mediated transient expression assays in Nicotiana benthamiana to test if NPQ kinetics could be modified in fully expanded leaves. By expressing Arabidopsis thaliana genes known to be involved in NPQ, we confirmed the viability of this method for studying dynamic photosynthetic processes. Subsequently, we used naturally occurring variation in photosystem II subunit S, a modulator of NPQ in plants, to explore how differences in amino acid sequence affect NPQ capacity and kinetics. Finally, we functionally characterized four predicted carotenoid biosynthesis genes from the marine algae Nannochloropsis oceanica and Thalassiosira pseudonana and examined the effect of their expression on NPQ in N. benthamiana. This method offers a powerful alternative to traditional gene characterization methods by providing a fast and easy platform for assessing gene function in planta

Design and implementation of sensor systems for control of a closed-loop life support system

The sensing and controlling needs for a Closed-Loop Life Support System (CLLSS) were investigated. The sensing needs were identified in five particular areas and the requirements were defined for workable sensors. The specific areas of interest were atmosphere and temperature, nutrient delivery, plant health, plant propagation and support, and solids processing. The investigation of atmosphere and temperature control focused on the temperature distribution within the growth chamber as well as the possibility for sensing other parameters such as gas concentration, pressure, and humidity. The sensing needs were studied for monitoring the solution level in a porous membrane material along with the requirements for measuring the mass flow rate in the delivery system. The causes and symptoms of plant disease were examined and the various techniques for sensing these health indicators were explored. The study of sensing needs for plant propagation and support focused on monitoring seed viability and measuring seed moisture content as well as defining the requirements for drying and storing the seeds. The areas of harvesting, food processing, and resource recycling, were covered with a main focus on the sensing possibilities for regulating the recycling process

Water and Energy Requirements for Outdoor Algal Cultivation in Panel and Raceway Photobioreactors

abstract: Recognition of algae as a “Fit for Purpose” biomass and its potential as an energy and bio-product resource remains relatively obscure. This is due to the absence of tailored and unified production information necessary to overcome several barriers for commercial viability and environmental sustainability. The purpose of this research was to provide experimentally verifiable estimates for direct energy and water demand for the algal cultivation stage which yields algal biomass for biofuels and other bio-products. Algal biomass productivity was evaluated using different cultivation methods in conjunction with assessment for potential reduction in energy and water consumption for production of fuel and feed. Direct water and energy demands are the major focal sustainability metrics in hot and arid climates and are influenced by environmental and operational variables connected with selected algal cultivation technologies. Evaporation is a key component of direct water demand for algal cultivation and directly related to variations in temperature and relative humidity. Temperature control strategies relative to design and operational variables were necessary to mitigate overheating of the outdoor algae culture in panel photobioreactors and sub-optimal cultivation temperature in open pond raceways. Mixing in cultivation systems was a major component in direct energy demand that was provided by aeration in panel bioreactors and paddlewheels in open pond raceways. Management of aeration time to meet required biological interactions provides opportunities for reduced direct energy demand in panel photobioreactors. However, the potential for reduction in direct energy demand in raceway ponds is limited to hydraulics and head loss. Algal cultivation systems were reviewed for potential integration into dairy facilities in order to determine direct energy demand and nutrient requirements for algal biomass production for animal feed. The direct energy assessment was also evaluated for key components of related energy and design parameters for conventional raceway ponds and a gravity fed system. The results of this research provide a platform for selecting appropriate production scenarios with respect to resource use and to ensure a cost effective product with the least environmental burden.Dissertation/ThesisDoctoral Dissertation Design 201

Rainwater harvesting system as a strategy for adaptation on climate change: a review

In the face of increasing water scarcity aggravated by climate change, the rainwater harvesting system is a technique that increases the water supply for various purposes. The objective of this research is to analyse the recent literature published on the rainwater collection system, for which the systematic review method was used. The main form of rainwater catchment are roofs, but the material used is important because it can affect the quality of the water. Some physicochemical parameters of rainwater may be within the standards for human consumption, but it is contaminated by pathogenic microorganisms, which represents a risk to public health if it is consumed without prior treatment, so it is mainly used for irrigation and flushing toilets. However, this system has been implemented mainly in rural areas to satisfy their basic needs, including human consumption, because these places do not have access to the central drinking water system. Given this scenario, treatment technologies are being developed that are easy to operate and maintain, such as solar disinfection and filtration for drinking water purposes. This study provides a global overview progress of research related to the rainwater harvesting system

Emerging renewable energy technologies: Survey, modeling, and simulations

This thesis approaches recent technologies to produce electric power from wind or water. The use of tethered kites for harnessing wind or water power and consequently transforming it into electric power is an idea which is starting to take off and with serious on-going developments. There are two types of major systems: Ground generation and on-board generation. The first one comprises a soaring kite tethered to a ground generator which generates electric power by means of reeling out the tether as the kite rises. This movement is controlled through the manipulation of its surface similar to the control of surfaces an aircraft. As for on-board generation, it is basically an aircraft with mounted generators on its wings, and tethered to the ground by a cable with the double function of securing and tethering the aircraft to the ground, as well as to bring the electric power from the aircraft to the grid. Both systems can be implemented on air and underwater. In the recent times there were serious developments in these technologies, one of them is the Makani Project powered by Google with a proven concept on-board generator of 600kW. Regarding underwater kite systems, there are several companies like Minesto (Saab spinoff) which also have a proven concept of 500kW. For these reasons and given the increasing power demand and accountability regarding energy sources, this work offers an overview of these ground-breaking technologies (compared against the conventional technologies) which can and will contribute to the decentralization of the electric energy production. In addition, this work provides a series of simulations and power estimates for kite systems to offer an unbiased view of this new type of electric energy harnessing.O uso de asas ou kites (vulgo papagaios) para aproveitar a força do vento ou da água e consequentemente transformá-la em energia elétrica é uma ideia que começa a ganhar forma nos últimos tempos e com desenvolvimentos muito significativos, que implicam um olhar mais atento sobre este tipo de tecnologia. Existem dois grandes grupos de sistemas: Geração no solo e em voo. A primeira consiste numa asa , ancorada a um gerador no solo através de um cabo, em que a energia elétrica é gerada pelo enrolar e desenrolar do cabo que o liga ao solo, à medida que a asa se movimenta ao sabor do vento, com a trajetória controlada através da alteração da superfície da asa de uma forma semelhante ao que acontece numa aeronave comum. Quanto à geração em voo, trata basicamente uma aeronave com geradores montados nas suas asas e ancorada ao solo através de um cabo com a função extra de efetuar a ligação elétrica entre a aeronave e a rede. Nos últimos tempos têm havido desenvolvimentos muito significativos nestas tecnologias, sendo que um deles chama especial atenção pela espetacularidade das imagens e por se tratar de uma empresa Google X – A Makani Project possui um conceito já provado de geração de 600kW. Da mesma forma e para geração subaquática, existem já diversas empresas entre elas a Minesto (constituída por engenheiros da Saab) com um conceito de 500kW. Por estas razões e dada a solicitação crescente a nível de energia elétrica e o aumento da responsabilização dos produtores de energia elétrica para o uso de fontes de energia renovável, este trabalho oferece um panorama geral sobre estas tecnologias inovadoras que terão um papel preponderante a desempenhar no futuro da descentralização do sistema elétrico-produtor

Mesopelagic-epipelagic fish nexus in viability and feasibility of commercial-scale mesopelagic fisheries

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kourantidou, M., & Jin, D. Mesopelagic-epipelagic fish nexus in viability and feasibility of commercial-scale mesopelagic fisheries. Natural Resource Modeling, 35(4), (2022): e12350, https://doi.org/10.1111/nrm.12350.While considerable scientific uncertainties persist for mesopelagic ecosystems, the fishing industry has developed a great interest in commercial exploitation with improved technologies as part of their search for new sources of feed for fishmeal and fish oil for aquaculture, which will intensify with the planet's growing population. The multiple uncertainties surrounding the ecosystem structure and particularly the size of biomass, hinder a good understanding of the risks associated with large-scale exploitation, which is needed for a management framework for sustainable ocean uses. Despite concerns regarding irreversible losses triggered by commercial fishing, work exploring the vulnerability of mesopelagic fish to harvesting is largely missing. This study investigates the economic feasibility of mesopelagic fishing which is the primary driver for any possible future expansion. Using very limited information currently available, we conduct a high-level assessment focusing on key ecological and economic interactions and develop an initial understanding of the economic feasibility of commercial harvesting for mesopelagic fish in the coming years. We conduct simulations using a classical bioeconomic model that captures two species groups, mesopelagic and epipelagic fish, using a wide range of price and cost parameters. We analyze different scenarios for the economic profitability of the fishery in a regional fishery management context. The results of our study highlight the importance of better understanding key biological and ecological mechanisms and parameters which can in turn help inform policies aimed at protecting the mesopelagic.This study is supported by WHOI's Ocean Twilight Zone program which is part of the Audacious Project, a collaborative endeavor, housed at TED

Assessment of cross-flow filtration as microalgae harvesting technique prior to anaerobic digestion: Evaluation of biomass integrity and energy demand

[EN] In the present study, the effect of cross-flow filtration (CFF) on the overall valorization of Chlorella spp. microalgae as biogas was assessed. The effect of CFF on microalgae cell integrity was quantified in terms of viability which was correlated with the anaerobic biodegradability. The viability dropped as the biomass concentration increased, whereas anaerobic biodegradability increased linearly with the viability reduction. It was hypothesized that a stress-induced release and further accumulation of organic polymers during CFF increased the flux resistance which promoted harsher shear-stress conditions. Furthermore, the volume reduction as the concentration increased entailed an increase in the specific energy supply to the biomass. The energy demand was positive in the whole range of concentrations studied, yielding an overall energy efficiency as high as 22.9% for the highest concentration studied. Specifically, heat requirements were lower than electricity requirements only when the biomass concentrations exceeded 10 g COD.L-1.This work was funded by the Spanish Ministry of Economy and Competitiveness with the support from the European Commission through the European Regional Development Funds (MINECO, CTM2011-28595-C02-01 and CTM2011-28595-C02-02), which are gratefully acknowledged. The authors would also express their gratitude to the Education, Investigation, Culture and Sports Council from the Valencian Generality for the Post-Doctoral fellowship awarded to Juan Bautista Gimenez Garcia (APOSTD/2016/104).Giménez García, J.; Bouzas Blanco, A.; Carrere, H.; Steyer, J.; Ferrer, J.; Seco Torrecillas, A. (2018). Assessment of cross-flow filtration as microalgae harvesting technique prior to anaerobic digestion: Evaluation of biomass integrity and energy demand. Bioresource Technology. 269:188-194. https://doi.org/10.1016/j.biortech.2018.08.052S18819426