The enzyme superoxide dismutase (SOD) holds a key position in the microalgal antioxidant network. The present research focused on oxidative stress responses in the Antarctic diatom Chaetoceros brevis F. Schütt during transition to excess (including ultraviolet radiation [UVR]) and limiting irradiance conditions. Over a 4 d period, cellular responses of thiobarbituric acid reactive substances (T...

Aeschynanthus longicaulis plants are understory plants in the forest, adapting to low light conditions in their native habitats. To observe the effects of the high irradiance on growth and physiology, plants were grown under two different light levels, PPFD 650 μmol·m(-2) ·s(-1) and 150 μmol·m(-2) ·s(-1) for 6 months. Plants under high irradiance had significantly thicker leaves with smaller le...

Establishing human habitation on the Moon or Mars requires development of a palette interconnected reaction chemistries to transform their native soils into structural metals, fuels, propellants, and load-bearing forms. This article outlines key research needs relevant fundamental chemistry in situ resource utilization.

It has long been known that the microbial component of terrestrial ecosystems provides capacity for nutrient and elemental cycling other key ecosystem services. Advances in DNA sequencing technology analytical continue to reveal novel insights into structure dynamics these ecosystems. These have led an increasing appreciation importance species associate with multicellular organisms, including ...

The effectiveness of neonatal hyperbilirubinaemia treatment depends directly on the amount of energy emitted by light (irradiance). This cross-sectional study aimed to determine the irradiance of phototherapy equipment in maternity wards in Maceió, AL, Brazil. All equipment in use in the neonatal units in Maceió was included in the study, totaling 36 devices, except those in maintenance. The me...

The detection of variations in solar irradiance by satellitebased experiments during the last 17 years stimulated modelling e orts to help to identify their causes and to provide estimates for irradiance data when no satellite observations exist. Because of the lack of quantitative physical models of solar irradiance, the current empirical models have been developed with linear regression analy...

Mammalian retinal photoreceptors form an irradiance detection system that drives many nonvisual responses to light such as pupil reflex and resetting of the circadian clock. To understand the role of pupil size in circadian light responses, pupil diameter was pharmacologically manipulated and the effect on behavioral phase shifts at different irradiance levels was studied in the Syrian hamster....

[1] Solar irradiance is the main external driver of the Earth’s climate. Whereas the total solar irradiance is the main source of energy input into the climate system, solar UV irradiance exerts control over chemical and physical processes in the Earth’s upper atmosphere. The time series of accurate irradiance measurements are, however, relatively short and limit the assessment of the solar con...