scholarly journals Mitochondria are specifically vulnerable to 420nm light in drosophila which undermines their function and is associated with reduced fly mobility

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0257149
Author(s):  
Jaimie Hoh Kam ◽  
Chris Hogg ◽  
Robert Fosbury ◽  
Harpreet Shinhmar ◽  
Glen Jeffery
Keyword(s):  
Membrane Permeability ◽  
Light Exposure ◽  
Complex Activity ◽  
Mitochondrial Inner Membrane ◽  
Specific Absorbance ◽  
Short Wavelength Light ◽  
Reduced Mobility ◽  
The Impact ◽  
Visual Range ◽  
Complex Activities

Increased blue light exposure has become a matter of concern as it has a range of detrimental effects, but the mechanisms remain unclear. Mitochondria absorb short wavelength light but have a specific absorbance at 420nm at the lower end of the human visual range. This 420nm absorption is probably due to the presence of porphyrin. We examine the impact of 420nm exposure on drosophila melanogaster mitochondria and its impact on fly mobility. Daily 15 mins exposures for a week significantly reduced mitochondrial complex activities and increased mitochondrial inner membrane permeability, which is a key metric of mitochondrial health. Adenosine triphosphate (ATP) levels were not significantly reduced and mobility was unchanged. There are multiple options for energy/time exposure combinations, but we then applied single 420nm exposure of 3h to increase the probability of an effect on ATP and mobility, and both were significantly reduced. ATP and mitochondrial membrane permeability recovered and over corrected at 72h post exposure. However, despite this, normal mobility did not return. Hence, the effect of short wavelengths on mitochondrial function is to reduce complex activity and increasing membrane permeability, but light exposure to reduce ATP and to translate into reduced mobility needs to be sustained.

scholarly journals Short-Wavelength Light Enhances Cortisol Awakening Response in Sleep-Restricted Adolescents

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Mariana G. Figueiro ◽  
Mark S. Rea
Keyword(s):  
Adrenal Gland ◽  
Short Wavelength ◽  
Light Exposure ◽  
Secondary Analysis ◽  
Cortisol Awakening Response ◽  
Dim Light ◽  
Short Wavelength Light ◽  
The Impact ◽  
Rising Time ◽  
Wavelength Light

Levels of cortisol, a hormone produced by the adrenal gland, follow a daily, 24-hour rhythm with concentrations reaching a minimum in the evening and a peak near rising time. In addition, cortisol levels exhibit a sharp peak in concentration within the first hour after waking; this is known as the cortisol awakening response (CAR). The present study is a secondary analysis of a larger study investigating the impact of short-wavelength(λmax≈470 nm)light on CAR in adolescents who were sleep restricted. The study ran over the course of three overnight sessions, at least one week apart. The experimental sessions differed in terms of the light exposure scenarios experienced during the evening prior to sleeping in the laboratory and during the morning after waking from a 4.5-hour sleep opportunity. Eighteen adolescents aged 12–17 years were exposed to dim light or to 40 lux (0.401 W/m2) of 470-nm peaking light for 80 minutes after awakening. Saliva samples were collected every 20 minutes to assess CAR. Exposure to short-wavelength light in the morning significantly enhanced CAR compared to dim light. Morning exposure to short-wavelength light may be a simple, yet practical way to better prepare adolescents for an active day.

scholarly journals Ground-Based MAX-DOAS Observations of Tropospheric NO2 and HCHO During COVID-19 Lockdown and Spring Festival Over Shanghai, China

2021 ◽  
Vol 13 (3) ◽  
pp. 488
Author(s):  
Aimon Tanvir ◽  
Zeeshan Javed ◽  
Zhu Jian ◽  
Sanbao Zhang ◽  
Muhammad Bilal ◽  
...  
Keyword(s):  
Air Quality ◽  
Anthropogenic Activities ◽  
Anthropogenic Activity ◽  
Hysplit Model ◽  
Vertical Column ◽  
Weekly Cycle ◽  
Spring Festival ◽  
Level 1 ◽  
Reduced Mobility ◽  
The Impact

Reduced mobility and less anthropogenic activity under special case circumstances over various parts of the world have pronounced effects on air quality. The objective of this study is to investigate the impact of reduced anthropogenic activity on air quality in the mega city of Shanghai, China. Observations from the highly sophisticated multi-axis differential optical absorption spectroscope (MAX-DOAS) instrument were used for nitrogen dioxide (NO2) and formaldehyde (HCHO) column densities. In situ measurements for NO2, ozone (O3), particulate matter (PM2.5) and the air quality index (AQI) were also used. The concentration of trace gases in the atmosphere reduces significantly during annual Spring Festival holidays, whereby mobility is reduced and anthropogenic activities come to a halt. The COVID-19 lockdown during 2020 resulted in a considerable drop in vertical column densities (VCDs) of HCHO and NO2 during lockdown Level-1, which refers to strict lockdown, i.e., strict measures taken to reduce mobility (43% for NO2; 24% for HCHO), and lockdown Level-2, which refers to relaxed lockdown, i.e., when the mobility restrictions were relaxed somehow (20% for NO2; 22% for HCHO), compared with pre-lockdown days, as measured by the MAX-DOAS instrument. However, for 2019, a reduction in VCDs was found only during Level-1 (24% for NO2; 6.62% for HCHO), when the Spring Festival happened. The weekly cycle for NO2 and HCHO depicts no significant effect of weekends on the lockdown. After the start of the Spring Festival, the VCDs of NO2 and HCHO showed a decline for 2019 as well as 2020. Backward trajectories calculated using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model indicated more air masses coming from the sea after the Spring Festival for 2019 and 2020, implying that a low pollutant load was carried by them. No impact of anthropogenic activity was found on O3 concentration. The results indicate that the ratio of HCHO to NO2 (RFN) fell in the volatile organic compound (VOC)-limited regime.

scholarly journals Agricultural Cooperatives and COVID-19 in Southeast Africa. The Role of Managerial Capital for Rural Resilience

2021 ◽  
Vol 13 (3) ◽  
pp. 1046
Author(s):  
Nicola Francesconi ◽  
Fleur Wouterse ◽  
Dorothy Birungi Namuyiga
Keyword(s):  
Health Impact ◽  
Value Chains ◽  
Agricultural Cooperatives ◽  
African Countries ◽  
Elite Capture ◽  
Innovative Solutions ◽  
Reduced Mobility ◽  
The Impact ◽  
Food Value

While the health impact of COVID-19 in most African countries appears modest, the impact of social distancing measures, closing of markets and reduced mobility is felt across the board. Domestic, labor-intensive and traditional food value chains and the smallholders they serve appear to be particularly affected. During a systemic shock where idiosyncratic risk coping strategies fail, collective or organizational resilience becomes of the essence to protect the livelihoods of smallholders. In this study, we have used pre- and during-shock data on agricultural cooperatives from Southeast Africa to understand how resilient these smallholder-owned organizations are. We find that many organizations could not countervail market-disruptions and fell into a state of dormancy during the pandemic. One reason for this is that collective decision-making was heavily affected by the banning of gatherings. Only a few organizations devised innovative solutions to maintain the market linkages of rural smallholders. The lack of resilience demonstrated by most cooperatives appears to be associated with organizational immaturity, large membership size, elite capture and limited business-orientation, which underscore a general lack of managerial capital.

scholarly journals Fundamentals of circadian entrainment by light

2021 ◽  
Vol 53 (5) ◽  
pp. 377-393
Author(s):  
RG Foster
Keyword(s):  
Ganglion Cells ◽  
Light Exposure ◽  
Bright Light ◽  
Evidence Based ◽  
Retinal Ganglion ◽  
Rods And Cones ◽  
Long Duration ◽  
Lighting Systems ◽  
Short Wavelength Light ◽  
Wavelength Light

Light at dawn and dusk is the key signal for the entrainment of the circadian clock. Light at dusk delays the clock. Light at dawn advances the clock. The threshold for human entrainment requires relatively bright light for a long duration, but the precise irradiance/duration relationships for photoentrainment have yet to be fully defined. Photoentrainment is achieved by a network of photosensitive retinal ganglion cells (pRGCs) which utilise the short-wavelength light-sensitive photopigment, melanopsin. Although rods and cones are not required, they do play a role in photoentrainment, by projecting to and modulating the endogenous photosensitivity of the pRGCs, but in a manner that remains poorly understood. It is also important to emphasise that the age and prior light exposure of an individual will modify the efficacy of entrainment stimuli. Because of the complexity of photoreceptor interactions, attempts to develop evidence-based human centric lighting are not straightforward. We need to study how humans respond to dynamic light exposure in the ‘real world’ where light intensity, duration, spectral quality and the time of exposure vary greatly. Defining these parameters will allow the development of electric lighting systems that will enhance human circadian entrainment.

scholarly journals A conceptual simulation workflow to guide design decisions regarding the effects of daylight on occupants’ alertness

2021 ◽  
Vol 2042 (1) ◽  
pp. 012116
Author(s):  
Pierson Clotilde ◽  
Soto Magán Victoria Eugenia ◽  
Aarts Mariëlle ◽  
Andersen Marilyne
Keyword(s):  
Light Exposure ◽  
Well Being ◽  
Research Field ◽  
Decision Makers ◽  
Spectral Simulation ◽  
Design Decisions ◽  
Computational Tools ◽  
Recent Developments ◽  
The Impact

Abstract Recent developments in the lighting research field have demonstrated the importance of a proper exposure to light to mediate several of our behavioral and physiological responses. However, we spend nowadays around 90% of our time indoors with an often quite limited access to bright daylight. To be able to anticipate how much the built environment actually influences our light exposure, and how much it may ultimately impact our health, well-being, and productivity, new computational tools are needed. In this paper, we present a first attempt at a simulation workflow that integrates a spectral simulation tool with a light-driven prediction model of alertness. The goal is to optimize the effects of light on building occupants, by informing the decision makers about the impact of different design choices. The workflow is applied to a case study to provide an example of what learnings can be expected from it.

scholarly journals How the global economy reflected the year of the pandemic

2021 ◽  
Vol 129 ◽  
pp. 01014
Author(s):  
Vladislav Kaputa ◽  
Frederik Kvočák ◽  
Miroslava Triznová ◽  
Andrej Tomić ◽  
Hana Maťová
Keyword(s):  
Global Economy ◽  
Value Added ◽  
Point Of View ◽  
Environmental Aspects ◽  
Data Comparison ◽  
The Social ◽  
Macroeconomic Indicators ◽  
The Individual ◽  
Reduced Mobility ◽  
The Impact

Research background: The coronavirus pandemic in 2020 had a significant impact on all aspects of life, from the point of view of the individual by forcing social isolation, moving work and study to the home, enormous pressure on the social and health system, but also by forcing closures of services and direct contact with customers. These, as well as other factors, have also had an impact on the performance of economies around the world. Purpose of the article: The paper aims to evaluate the development of the world's major economies in terms of macroeconomic indicators and foreign trade in the pandemic period and previous periods. The social and environmental aspects of the impact of the pandemic on selected economies are also reflected. Methods: Analysis of the main macroeconomic data, comparison and synthesis of findings. Findings & Value added: The interdependence of economies and interconnectedness of markets on transport routes associated with reduced mobility, forced isolation of people and death of economic activity had a significant impact on all the observed indicators, where a significant decline in GDP could be observed in all countries except China. This country was the only one that managed to keep GDP growth in positive numbers. Unemployment development was not equal in the observed economies due to different labour market environment. On the contrary, the environment has benefited in some way.

scholarly journals Objective Behavioral Measures in Children before, during, and after the COVID-19 Lockdown in Israel

2021 ◽  
Vol 18 (16) ◽  
pp. 8732
Author(s):  
Einat Shneor ◽  
Ravid Doron ◽  
Jonathan Levine ◽  
Deena Rachel Zimmerman ◽  
Julia S. Benoit ◽  
...  
Keyword(s):  
Physical Activity ◽  
Light Exposure ◽  
Vigorous Physical Activity ◽  
Rank Test ◽  
Long Term Effects ◽  
Wake Time ◽  
Signed Rank ◽  
Social Restriction ◽  
Signed Rank Test ◽  
The Impact

Studies using questionnaires report that COVID-19 restrictions resulted in children spending significantly less time outdoors. This study used objective measures to assess the impact of pandemic-related restrictions on children’s behavior. A total of 19 healthy 8–12-year-old boys were observed before and during social restriction periods. Of these, 11 boys were reassessed after restrictions were lifted. For each session, Actiwatches were dispensed for measures of time outdoors, activity, and sleep. Changes overall and by school status were assessed using signed-rank test and Wilcoxon rank sum tests. During restrictions, children spent significantly less time outdoors (p = 0.001), were less active (p = 0.001), and spent less time engaged in moderate-to-vigorous physical activity (p = 0.004). Sleep duration was not significantly different between sessions (p > 0.99), but bedtime and wake time shifted to a later time during restrictions (p < 0.05 for both). Time outdoors and activity returned close to pre-pandemic levels after restrictions were lifted (p > 0.05 for both). Children’s behaviors significantly changed during the COVID-19 pandemic. The reduction in outdoor light exposure is of importance due to the role of light in the etiology of myopia and vitamin D production. The reduction in physical activity may have negative health effects in terms of obesity and depression, although further research is required to ascertain the long-term effects.

Osteogenesis Imperfecta: The Impact of Genotype and Clinical Phenotype on Adiposity and Resting Energy Expenditure

2021 ◽  
Author(s):  
Kaitlin L Ballenger ◽  
Nicol Tugarinov ◽  
Sara K Talvacchio ◽  
Marianne M Knue ◽  
An N Dang Do ◽  
...  
Keyword(s):  
Energy Expenditure ◽  
Osteogenesis Imperfecta ◽  
Type I Collagen ◽  
Resting Energy Expenditure ◽  
Type I ◽  
Healthy Controls ◽  
Type Iv ◽  
Reduced Mobility ◽  
The Impact ◽  
Resting Energy

Abstract Context Mutations in type I collagen or collagen-related proteins cause Osteogenesis Imperfecta (OI). Energy expenditure and body composition in OI could reflect reduced mobility, or intrinsic defects in osteoblast differentiation increasing adipocyte development. Objective Compare adiposity and resting energy expenditure (REE) in OI and healthy controls (HC), for OI genotype- and Type-associated differences. Design/Setting/Participants We studied 90 participants, 30 with OI (13 COL1A1 Gly, 6 COL1A2 Gly, 3 COL1A1 non-Gly, 2 COL1A2 non-Gly, 6 non-COL; 8 Type III, 16 Type IV, 4 Type VI, 1 Type VII, 1 Type XIV) and 60 HC with sociodemographic characteristics/BMI/BMIz similar to the OI group. Participants underwent dual-energy X-ray absorptiometry to determine lean mass and fat mass percentage (FM%) and REE. FM% and REE were compared, adjusting for covariates to examine the relationship of OI genotypes and phenotypic Types. Results FM% did not differ significantly in all patients with OI versus HC (OI: 36.6±1.9%, HC: 32.7±1.2%, p =0.088). FM% was, however, greater than HC for those with non-COL variants (p=0.018). FM% did not differ from HC among OI Types (p’s&gt;0.05). Overall, covariate-adjusted REE did not differ significantly between OI and HC (OI: 1376.5±44.7 kcal/d, healthy controls: 1377.0±96 kcal/d p=0.345). However, those with non-COL variants (p=0.034) and Type VI OI (p=0.04) had significantly lower REE than HC. Conclusions Overall, patients with OI did not significantly differ in either extra-marrow adiposity or REE from BMI-similar HC. However, reduced REE among those with non-COL variants may contribute to greater adiposity.

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