Remote light stress detection for greenhouse LED lighting control

The illumination in greenhouses is in general still controlled manually by on/off control because of the type of lamps (High Pressure Sodium) that are traditionally used. With High Brightness LEDs being introduced on the market today, sufficiently high power for greenhouse grown crops can be achieved, which opens up for advanced lighting control since both light spectrum and intensity can be controlled then. For the growers, maximizing production in order to meet customer demand and economically optimize the production, often imply a high light intensity and a high level of artificial light complementing the natural sunlight. However, a too high intensity causes light stress and a photo inhibition that can significantly reduce the photosynthetic yield and hence, production. A key issue to address is therefore to detect when this level is reached. Here we present new results on how to diagnose the plants remotely based on transient and frequency analysis, system identification and frequency function properties

The characterisation of a galactokinase from Streptomyces coelicolor

Promiscuous galactokinases (GalKs), which catalyse the ATP dependent phosphorylation of galactose in nature, have been widely exploited in biotechnology for the rapid synthesis of diverse sugar-1-phosphates. This work focuses on the characterisation of a bacterial GalK from Streptomyces coelicolor (ScGalK), which was overproduced in Escherichia coli and shown to phosphorylate galactose. ScGalK displayed a broad substrate tolerance, with activity towards Gal, GalN, Gal3D, GalNAc, Man and L-Ara. Most interestingly, ScGalK demonstrated a high activity over a broad pH and temperature range, suggesting that the enzyme could be highly amenable to multi-enzyme systems

Assessing School Neighbourhood Environments for Active Transport to Secondary Schools in Dunedin, New Zealand

Background: Adolescent active transport to school (ATS) is influenced by demographic, social, environmental and policy factors. Yet, the relationship between school neighbourhood built environment and adolescents’ ATS remains largely unexplored. This observational study extended the Built Environment and Active Transport to School (BEATS) Study to examine associations between observed, objectively-measured and perceived school neighbourhood built environments and rates of ATS across all twelve Dunedin (New Zealand) secondary schools. Methods: Microscale Audit of Pedestrian Streetscapes Global (MAPS Global) audits were physically conducted within a 0.5 km street-network buffer-zone of all schools. Sub-scale and overall summary scores were calculated. Intersection density, residential density, land use mix and walkability of school neighbourhood built environments were computed using Geographic Information Systems (GIS) spatial analysis over several street-network buffer zones (0.5 km, 1.0 km, 1.5 km and 2.25 km). School-specific ATS rates and perceptions of the school route from adolescents living ≤2.25 km from school (BEATS Study data: n=473; age: 15.2±1.4 years; 56.2% female) complemented analyses. Data were analysed using Pearson’s Product Moment correlations and Spearman’s Rank correlation coefficients. Results: School-level ATS rates were not significantly correlated with MAPS Global, GIS measures (0.5 or 2.25 km buffer zones) or adolescents’ perceptions of the school route. MAPS Global pedestrian design sub-scale (0.5 km: r=0.62), GIS-determined intersection density (0.5/2.25 km: r=0.77/r=0.64), land use mix (2.25 km: r=0.64) and walkability index (0.5/2.25 km: r=0.86/r=0.73) positively correlated with adolescents’ perception of dangerous crossings. MAPS Global pedestrian infrastructure sub-scale (0.5 km: r=-0.66) negatively correlated with walking safety concerns. Intersection density positively correlated with cycling safety concerns (0.5 km: r=0.68) and perceived cycle lane absence (0.5 km: r=0.65), while land use mix positively correlated with adolescents’ perception of high traffic volume (2.25 km: r=0.72). GIS-determined walkability index positively correlated with walking/cycling safety concerns (0.5 km: cycling: r=0.72; 2.25 km: r=0.68/r=0.66), high traffic volume (0.5 km: r=0.73), and absence of footpaths (0.5 km: r=0.62) and cycle lanes (2.25 km: r=0.71) (all p<0.05). Conclusions: Assessed micro- and macro-scale school neighbourhood built environment characteristics were significantly correlated with Dunedin adolescents’ perceptions of the school route, but not with ATS rates among adolescents living ≤2.25 km of school. The school neighbourhood built environment should be considered as a part of comprehensive efforts to enhance perceptions of safety and encourage ATS

Assessing School Neighbourhood Environments for Active Transport to Secondary Schools in Dunedin, New Zealand

Background: Adolescent active transport to school (ATS) is influenced by demographic, social, environmental and policy factors. Yet, the relationship between school neighbourhood built environment and adolescents’ ATS remains largely unexplored. This observational study extended the Built Environment and Active Transport to School (BEATS) Study to examine associations between observed, objectively-measured and perceived school neighbourhood built environments and rates of ATS across all twelve Dunedin (New Zealand) secondary schools. Methods: Microscale Audit of Pedestrian Streetscapes Global (MAPS Global) audits were physically conducted within a 0.5 km street-network buffer-zone of all schools. Sub-scale and overall summary scores were calculated. Intersection density, residential density, land use mix and walkability of school neighbourhood built environments were computed using Geographic Information Systems (GIS) spatial analysis over several street-network buffer zones (0.5 km, 1.0 km, 1.5 km and 2.25 km). School-specific ATS rates and perceptions of the school route from adolescents living ≤2.25 km from school (BEATS Study data: n=473; age: 15.2±1.4 years; 56.2% female) complemented analyses. Data were analysed using Pearson’s Product Moment correlations and Spearman’s Rank correlation coefficients. Results: School-level ATS rates were not significantly correlated with MAPS Global, GIS measures (0.5 or 2.25 km buffer zones) or adolescents’ perceptions of the school route. MAPS Global pedestrian design sub-scale (0.5 km: r=0.62), GIS-determined intersection density (0.5/2.25 km: r=0.77/r=0.64), land use mix (2.25 km: r=0.64) and walkability index (0.5/2.25 km: r=0.86/r=0.73) positively correlated with adolescents’ perception of dangerous crossings. MAPS Global pedestrian infrastructure sub-scale (0.5 km: r=-0.66) negatively correlated with walking safety concerns. Intersection density positively correlated with cycling safety concerns (0.5 km: r=0.68) and perceived cycle lane absence (0.5 km: r=0.65), while land use mix positively correlated with adolescents’ perception of high traffic volume (2.25 km: r=0.72). GIS-determined walkability index positively correlated with walking/cycling safety concerns (0.5 km: cycling: r=0.72; 2.25 km: r=0.68/r=0.66), high traffic volume (0.5 km: r=0.73), and absence of footpaths (0.5 km: r=0.62) and cycle lanes (2.25 km: r=0.71) (all p<0.05). Conclusions: Assessed micro- and macro-scale school neighbourhood built environment characteristics were significantly correlated with Dunedin adolescents’ perceptions of the school route, but not with ATS rates among adolescents living ≤2.25 km of school. The school neighbourhood built environment should be considered as a part of comprehensive efforts to enhance perceptions of safety and encourage ATS

Remote Detection of Growth Dynamics in Red Lettuce Using a Novel Chlorophyll a Fluorometer

The production of food crops in controlled environment agriculture (CEA) can help mitigate food insecurity that may result from increasingly frequent and severe weather events in agricultural areas. Lighting is an absolute requirement for crop growth in CEA, and is undergoing rapid advances with the advent of tunable, light emitting diode (LED) systems. The integration of these systems into existing CEA environmental control architectures is in its infancy and would benefit from a non-invasive, rapid, real-time, remote sensor that could track crop growth under different lighting regimes. A newly-developed remote chlorophyll a fluorescence (ChlF) sensing device is described herein that provides direct, remote, real-time physiological data collection for integration into tunable LED lighting control systems, thereby enabling better control of crop growth and energy efficiency. Data collected by this device can be used to accurately model growth of red lettuce plants. In addition to monitoring growth, this system can predict relative growth rates (RGR), net assimilation rates (NAR), plant area (PA), and leaf area ratio (LAR)

Method for controlling a growth cycle for growing plants using state oriented control

The present invention relates to a method for controlling a growth cycle for growing plants. Such a method may be implemented in a greenhouse, a walk-in chamber or a growth cabinet. The invention also relates to a corresponding system, use of the system and a computer program product. The invention allows for improvements in operating a greenhouse, such as in relation to reduced energy consumption and increased predictability of the growth process

Method for controlling a growth cycle for growing plants using state oriented control

The present invention relates to a method for controlling a growth cycle for growing plants. Such a method may be implemented in a greenhouse, a walk-in chamber or a growth cabinet. The invention also relates to a corresponding system, use of the system and a computer program product. The invention allows for improvements in operating a greenhouse, such as in relation to reduced energy consumption and increased predictability of the growth process

Spectrum optimization for artificial illumination

The present invention relates to a method for optimizing a spectrum of light emitted by an illumination system in a photosynthetic environment, such as for example using an illumination system arranged in a greenhouse, a walk-in chamber or a growth cabinet. The invention also relates to a corresponding illumination system and a computer program product

Spectrum optimization for artificial illumination

The present invention relates to a method for optimizing a spectrum of light emitted by an illumination system in a photosynthetic environment, such as for example using an illumination system arranged in a greenhouse, a walk-in chamber or a growth cabinet. The invention also relates to a corresponding illumination system and a computer program product

Growth doubling times for batch-grown cultures of <i>C. reinhardtii</i> grown in the presence of EE2 at concentrations ranging from 10 pM to 10 µM in the culture media.

<p>Control  =  no EE2 added. Growth was determined by daily measurements of A₇₅₀, for a minimum of 10 days. Data represent means ± SE, n = 3. * above a bar indicates a significant change as compared to the control using a student's t-test and <i>p</i><0.05.</p