Passive remote sensing of airborne chemicals at infrared wavelengths may be limited by temporal fluctuations in atmospheric brightness temperatures deltaT(t). Brightness temperatures in two infrared spectral bands were simultaneously measured on clear and cloudy days along three lines of sights. For time windows t < 3-5 s, deltaT(t) remained constant at the sensor noise level and rapidly increased as t increased. The fluctuation time scale for the cloudy day was longer than for the clear day. The long correlation time for T(t) limits the utility of signal averaging in improving detection signal-to-noise ratio (SNR). The simultaneous outputs of the two spectral channels during the clear day exhibited no spectral coherence at t < 3 s and limited coherence at t > 30 s. Measurements during the cloudy day were largely coherent. Consequently, band-by-band subtraction may have limited benefits.
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http://dx.doi.org/10.1364/opex.13.008781 | DOI Listing |
Mar Drugs
December 2024
Consiglio Nazionale delle Ricerche (CNR), Istituto di Chimica Biomolecolare (ICB), Via Campi Flegrei 34, 80078 Pozzuoli, Napoli, Italy.
The waters around the western Antarctic Peninsula are experiencing fast warming due to global change, being among the most affected regions on the planet. This polar area is home to a large and rich community of benthic marine invertebrates, such as sponges, tunicates, corals, and many other animals. Among the sponges, the bright yellow is commonly known for using secondary diterpenoids as a defensive mechanism against local potential predators.
View Article and Find Full Text PDFEur J Neurosci
January 2025
Institute of Physiology, Sleep Research & Clinical Chronobiology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
Timing and architecture of sleep are co-driven by circadian rhythms modulated by their major Zeitgeber light and darkness. In a natural environment, one is exposed to 3.000 lx (cloudy winter sky) to 100.
View Article and Find Full Text PDFPLoS One
January 2025
Marine Animal Ecology, Wageningen University & Research, Wageningen, The Netherlands.
Restoration and artificial reefs can assist the recovery of degraded reefs but are limited in scalability and climate resilience. The Mineral Accretion Technique (MAT) subjects metal artificial reefs to a low-voltage electrical current, thereby creating a calcium-carbonate coating. It has been suggested that corals on MAT structures experience enhanced health and growth.
View Article and Find Full Text PDFSoft Matter
January 2025
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
The impact of animal-based food production on climate change drives the development of plant-based alternatives. We demonstrate the use of colloidal thermogelation on a real nanoemulsion system to create structured gels that could be of interest for thermo-mechanical processing of next-generation plant-based food applications. We use a commercial pea protein isolate (PPI) without further purification to stabilize a 20 vol% peanut oil-in-water nanoemulsion at pH = 7 by high-pressure homogenization (HPH) and demonstrate the temperature induced gelation behavior of the nanoemulsion as a function of the HPH processing parameters.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University Marine Lab, Beaufort, NC 28516.
Ecosystem restoration has historically been viewed as an ecological endeavor, but restoration possesses significant, yet largely untapped, potential as a catalyst for personal and social transformation. We highlight the opportunity for restoration to enhance community resilience by increasing agency and collective action and countering the pervasive perception that we are powerless witnesses to environmental decline. In this perspective, we take a "bright spots" approach and highlight successful examples of ecosystem restoration that have helped to nurture a sense of place, foster optimism, and cultivate stronger and more diverse social networks.
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