Search results for "190"
showing 10 items of 346 documents
Sun-Induced Chlorophyll Fluorescence I: Instrumental Considerations for Proximal Spectroradiometers
2019
Growing interest in the proximal sensing of sun-induced chlorophyll fluorescence (SIF) has been boosted by space-based retrievals and up-coming missions such as the FLuorescence EXplorer (FLEX). The European COST Action ES1309 “Innovative optical tools for proximal sensing of ecophysiological processes” (OPTIMISE, ES1309; https://optimise.dcs.aber.ac.uk/) has produced three manuscripts addressing the main current challenges in this field. This article provides a framework to model the impact of different instrument noise and bias on the retrieval of SIF; and to assess uncertainty requirements for the calibration and characterization of state-of-the-art SIF-oriented spectroradiom…
Dental wear at macro- and microscopic scale in rabbits fed diets of different abrasiveness: A pilot investigation
2020
To differentiate the effects of internal and external abrasives on tooth wear, we performed a controlled feeding experiment in rabbits fed diets of varying phytolith content as an internal abrasive and with addition of sand as an external abrasive. 13 rabbits were each fed one of the following four pelleted diets with different abrasive characteristics (no phytoliths: lucerne L; phytoliths: grass G; more phytoliths: grass and rice hulls GR; phytoliths plus external abrasives: grass, rice hulls and sand GRS) for two weeks. At the end the feeding period, three tooth wear proxies were applied to quantify wear on the cheek teeth at macroscopic and microscopic wear scales: CT scans were obtained…
Transient metazoan reefs in the aftermath of the end-Permian mass extinction
2011
5 pages; International audience; Recovery from the devastating Permian-Triassic mass extinction about 252 million years ago is usually assumed to have spanned the entire 5 million years of the Early Triassic epoch1,2. The post-crisis interval was characterized by large-scale fluctuations of the global carbon cycle and harsh marine conditions, including a combination of ocean acidification, euxinia, and fluctuating productivity3. During this interval, metazoan-dominated reefs are thought to have been replaced by microbial deposits that are considered the hallmark of the Early Triassic4-7. Here we use field and microscopic investigations to document Early Triassic bioaccumulations and reefs f…
Nonlinear femtosecond pulse propagation in an all-solid photonic bandgap fiber
2009
Nonlinear femtosecond pulse propagation in an all-solid photonic bandgap fiber is experimentally and numerically investigated. Guiding light in such fiber occurs via two mechanisms: photonic bandgap in the central silica core or total internal reflection in the germanium doped inclusions. By properly combining spectral filtering, dispersion tailoring and pump coupling into the fiber modes, we experimentally demonstrate efficient supercontinuum generation with controllable spectral bandwidth.
Multi-sensor spectral synergies for crop stress detection and monitoring in the optical domain: A review
2022
Nitrogen isotopes in tooth enamel record diet and trophic level enrichment: results from a controlled feeding experiment
2021
Nitrogen isotope ratios (δ15N) are a well-established tool for investigating the dietary and trophic behavior of animals in terrestrial and marine food webs. To date, δ15N values in fossils have primarily been measured in collagen extracted from bone or dentin, which is susceptible to degradation and rarely preserved in deep time (>100,000 years). In contrast, tooth enamel organic matter is protected from diagenetic alteration by the mineral structure of hydroxyapatite and thus is often preserved over geological time. However, due to the low nitrogen content (<0.01 %) of enamel, the measurement of its nitrogen isotopic composition has been prevented by the analytical limit…
Músicas alternativas. Sobre formas de gestionar y producir músicas durante la década de 1980 en Córdoba- Argentina
2021
"Päihdyttävien juomien valmistamisesta ja käyttämisestä" : alkoholirikokset ja niiden kontrollointi Mikkelin seudulla 1895-1905
2017
Pro gradu-tutkielmassa kartoitetaan, millaisia alkoholirikoksia Mikkelin seudulla tehtiin ja miksi, kuten myös miten näitä rikoksia kontrolloitiin ja valvottiin vuosina 1895–1905. Tarkemmiksi tutkimuskohteiksi on rajattu kolme eniten oikeuksissa näkynyttä rikosta: viinan salapolttaminen, laiton myyminen sekä juopuminen julkisella alueella. Pääasiallisina lähteinä tutkimuksessa on käytetty rikoshistoriassa keskeisiä oikeusistuinten pöytäkirjoja sekä näiden tukena aikalaissanomalehtiä. Edellä mainituista kolmesta rikoksesta oli tutkimusajanjakson aikana syytettynä yhteensä 338 henkilöä. Suurin osa syytetyistä oli miehiä. Naisia oli mukana viinan salapolttamis- ja myymisrikoksissa, mutta juopu…
À la recherche du circuit idéal : le discours sur les autodromes et circuits automobiles dans L'Auto (1900-1939)
2022
Un tournant historiographique : l'histoire culturelle de la guerre en France
2015
International audience; ...