scholarly journals The Follow-up Photobioreactor Illumination System for the Cultivation of Photosynthetic Microorganisms

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1143 ◽  
Author(s):  
Beata Brzychczyk ◽  
Tomasz Hebda ◽  
Jakub Fitas ◽  
Jan Giełżecki

The article presents the basic conceptual assumptions of a photobioreactor with a complementary lighting system. The cylindrical bioreactor has three independent, interconnected, and fully controlled lighting systems. A characteristic feature is the combination of the lighting system with the measurement of photosynthetically active PAR (photosynthetically active radiation) and the optical density of the culture medium. The entire lighting system is based on RGBW (“red, green, blue, white”) LED and RBG (“red, green, blue”) LEDs. The pilot study was conducted on a simplified prototype of a photobioreactor designed for the distribution and optimization of light in algae cultures designed for energy purposes. The study was carried out on microalgae Chlorella Vulgaris BA0002a from the collection of marine algae cultures.

Author(s):  
Jinren Yan

AbstractIn this work, a scheme of combining an aspheric reflector and a primary packaging freeform lens in phosphor-converted lighting-emitting diode (pc-LED) based lighting system design was developed. In contrast to most of previous works in which the color and illumination uniformity of the pc-LED lighting systems were improved one by one, the developed scheme can improve both indicators simultaneously. To demonstrate the feasibility of the developed design scheme, an initially designed pc-LED optical model, with an average correlated color temperature (CCT) of about 5000 K, was constructed as the light source of the illumination system. The key ingredient to the color uniformity of the illumination system was investigated at first, and then several instances with the cut-off angle ranging from 40 to 60 degrees were further discussed. Detailed analysis shows: for each case, the CCT variation decreases from over 4000 K to smaller than 300 K and the illumination uniformity increases from a very low level to better than 80% on the target region.


Author(s):  
Teruaki Ito ◽  
Eiichi Honda ◽  
Tetsuo Ichikawa ◽  
Yosuke Kinouchi ◽  
Masatake Akutagawa ◽  
...  

The power spectrum of human heart rate measured over 24 h exhibits “power-law” 1/f alpha-type spectral behavior with alpha approximately 1. This may be one of the reasons why 1/f noise help people make relaxed, or feel comfortable. As a result, people feel relaxed by looking at a candle light, listening to the sound of ocean wave, or feeling the breezing wind because all of these natural phenomenon is based on the 1/f noise fluctuation. Considering this feature, a technical approach of 1/f noise fluctuation has been applied to various industry products, ranging from light illumination, fan control, temperature control, etc. to implement cozy products. For example, one typical example would be a lighting product mimicking a candle light, which illuminate just like a true candle. A candle light provides a cozy atmosphere to relax our mind by forgetting severe business issues, which is because of the nature of 1/f noise fluctuation as mentioned above. However, it is not suitable to do something important by concentration under a candle light because of the changes of brightness and the blinking nature of candles. This study designs and develops 1/f noise-fluctuated cozy lighting system with stable brightness and chromaticity without blinking so that people unconsciously feel relaxed under this lighting system without noticing the 1/f noise fluctuation and concentrate on work or operation. In order to implement this lighting system, combination of two types of white LED lights were used. White LED lights are manufactured by the combination of different colors having different spectrum. For example, Blue with YAG fluorophore, Blue with RG fluorophore, UV with RGB fluorophore, etc. provide all white LED lights. This means that it is possible to make two different types of LED lights which have the same white color with different combination of spectrums. If the two white colors of the two LED are the same, nobody cannot notice when the two LEDs are switching over each other, periodically or randomly. People only think that the white color is constantly provided by the white LED light. However, if the switching is based on 1/f noise fluctuation, some positive effect can be expected under this lighting system. This paper shows the overview of the idea of 1/f noise-fluctuated cozy lighting system, and then presents the two basic challenges of the idea towards concentration improvement; Combination of two types of white LED and 1/f noise-fluctuated switching system. These two challenges are presented using a prototype lighting systems developed in this study.


Crisis ◽  
2010 ◽  
Vol 31 (2) ◽  
pp. 109-112 ◽  
Author(s):  
Hui Chen ◽  
Brian L. Mishara ◽  
Xiao Xian Liu

Background: In China, where follow-up with hospitalized attempters is generally lacking, there is a great need for inexpensive and effective means of maintaining contact and decreasing recidivism. Aims: Our objective was to test whether mobile telephone message contacts after discharge would be feasible and acceptable to suicide attempters in China. Methods: Fifteen participants were recruited from suicide attempters seen in the Emergency Department in Wuhan, China, to participate in a pilot study to receive mobile telephone messages after discharge. All participants have access to a mobile telephone, and there is no charge for the user to receive text messages. Results: Most participants (12) considered the text message contacts an acceptable and useful form of help and would like to continue to receive them for a longer period of time. Conclusions: This suggests that, as a low-cost and quick method of intervention in areas where more intensive follow-up is not practical or available, telephone messages contacts are accessible, feasible, and acceptable to suicide attempters. We hope that this will inspire future research on regular and long-term message interventions to prevent recidivism in suicide attempters.


2019 ◽  
pp. 15-21
Author(s):  
Banu Manav

In lighting design, the main concept is to achieve a healthy environment, which addresses energy efficiency, cost, maintenance, and quality. User-friendly lighting systems shall be adopted to architecture and interior architecture. User control over the lighting system is important, by dimming or increasing light output, by changing the colour of the light sets the inner atmosphere and affects user mood. Standards and codes on lighting shall also be evaluated by means of these topics. The paper aims to analyse how the luminous environment is affective on the perceived environment. Hence, a series of experimental studies and recent research will be evaluated in regard to understanding and designing luminous environment.


2020 ◽  
pp. 1-7
Author(s):  
Michael Lumintang Loe ◽  
Tito Vivas-Buitrago ◽  
Ricardo A. Domingo ◽  
Johan Heemskerk ◽  
Shashwat Tripathi ◽  
...  

OBJECTIVEThe authors assessed the prognostic significance of various clinical and radiographic characteristics, including C1–C2 facet malalignment, in terms of surgical outcomes after foramen magnum decompression of adult Chiari malformation type I.METHODSThe electronic medical records of 273 symptomatic patients with Chiari malformation type I who were treated with foramen magnum decompression, C1 laminectomy, and duraplasty at Mayo Clinic were retrospectively reviewed. Preoperative and postoperative Neurological Scoring System scores were compared using the Friedman test. Bivariate analysis was conducted to identify the preoperative variables that correlated with the patient Chicago Chiari Outcome Scale (CCOS) scores. Multiple linear regression analysis was subsequently performed using the variables with p < 0.05 on the bivariate analysis to check for independent associations with the outcome measures. Statistical software SPSS version 25.0 was used for the data analysis. Significance was defined as p < 0.05 for all analyses.RESULTSFifty-two adult patients with preoperative clinical and radiological data and a minimum follow-up of 12 months were included. Motor deficits, syrinx, and C1–C2 facet malalignment were found to have significant negative associations with the CCOS score at the 1- to 3-month follow-up (p < 0.05), while at the 9- to 12-month follow-up only swallowing function and C1–C2 facet malalignment were significantly associated with the CCOS score (p < 0.05). Multivariate analysis showed that syrinx presence and C1–C2 facet malalignment were independently associated with the CCOS score at the 1- to 3-month follow-up. Swallowing function and C1–C2 facet malalignment were found to be independently associated with the CCOS score at the 9- to 12-month follow-up.CONCLUSIONSThe observed results in this pilot study suggest a significant negative correlation between C1–C2 facet malalignment and clinical outcomes evaluated by the CCOS score at 1–3 months and 9–12 months postoperatively. Prospective studies are needed to further validate the prognostic value of C1–C2 facet malalignment and the potential role of atlantoaxial fixation as part of the treatment.


2019 ◽  
Vol 18 (3) ◽  
pp. 232-238 ◽  
Author(s):  
Emanuela Onesti ◽  
Vittorio Frasca ◽  
Marco Ceccanti ◽  
Giorgio Tartaglia ◽  
Maria Cristina Gori ◽  
...  

Background: The cannabinoid system may be involved in the humoral mechanisms at the neuromuscular junction. Ultramicronized-palmitoylethanolamide (μm-PEA) has recently been shown to reduce the desensitization of Acetylcholine (ACh)-evoked currents in denervated patients modifying the stability of ACh receptor (AChR) function. <p> Objective: To analyze the possible beneficial effects of μm-PEA in patients with myasthenia gravis (MG) on muscular fatigue and neurophysiological changes. <p> Method: The duration of this open pilot study, which included an intra-individual control, was three weeks. Each patient was assigned to a 1-week treatment period with μm-PEA 600 mg twice a day. A neurophysiological examination based on repetitive nerve stimulation (RNS) of the masseteric and the axillary nerves was performed, and the quantitative MG (QMG) score was calculated in 22 MG patients every week in a three-week follow-up period. AChR antibody titer was investigated to analyze a possible immunomodulatory effect of PEA in MG patients. <p> Results: PEA had a significant effect on the QMG score (p=0.03418) and on RNS of the masseteric nerve (p=0.01763), thus indicating that PEA reduces the level of disability and decremental muscle response. Antibody titers did not change significantly after treatment. <p> Conclusion: According to our observations, μm-PEA as an add-on therapy could improve muscular response to fatigue in MG. The possible modulation of AChR currents as a means of eliciting a direct effect from PEA on the conformation of ACh receptors should be investigated. The co-role of cytokines also warrants an analysis. Given the rapidity and reversibility of the response, we suppose that PEA acts directly on AChR, though further studies are needed to confirm this hypothesis.


2014 ◽  
Vol 99 (Suppl 2) ◽  
pp. A520.2-A520
Author(s):  
L Charafeddine ◽  
R El Hage ◽  
H Tamim ◽  
L Akouri-Dirani ◽  
D Sinno

Energies ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 202
Author(s):  
Gianluca Serale ◽  
Luca Gnoli ◽  
Emanuele Giraudo ◽  
Enrico Fabrizio

Artificial lighting systems are used in commercial greenhouses to ensure year-round yields. Current Light Emitting Diode (LED) technologies improved the system efficiency. Nevertheless, having artificial lighting systems extended for hectares with power densities over 50W/m2 causes energy and power demand of greenhouses to be really significant. The present paper introduces an innovative supervisory and predictive control strategy to optimize the energy performance of the artificial lights of greenhouses. The controller has been implemented in a multi-span plastic greenhouse located in North Italy. The proposed control strategy has been tested on a greenhouse of 1 hectare with a lighting system with a nominal power density of 50 Wm−2 requiring an overall power supply of 1 MW for a period of 80 days. The results have been compared with the data coming from another greenhouse of 1 hectare in the same conditions implementing a state-of-the-art strategy for artificial lighting control. Results outlines that potential 19.4% cost savings are achievable. Moreover, the algorithm can be used to transform the greenhouse in a viable source of energy flexibility for grid reliability.


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