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Abstract Heterosis, Haldane and Bateson-Dobzhansky-Muller effects have been widely documented amongst a range of plants and animals. However, typically these effects are shown by taking parents of known genotype into the laboratory and measuring components of the F1 progeny under laboratory conditions. This leaves in doubt the real significance of such effects in the field. Here we use the well-known colour pattern genotypes of the African monarch or queen (Danaus chrysippus), which also control wing length, to test these effects both in the laboratory and in a contact zone in the field. By measuring the wing lengths in animals of known colour pattern genotype we show clear evidence for all three hybrid effects at the A and BC colour patterning loci, and importantly, that these same effects persist in the same presumptive F1s when measured in hybrid populations in the field. This demonstrates the power of a system in which genotypes can be directly inferred in the field and highlights that all three hybrid effects can be seen in the East African contact zone of this fascinating butterfly.

We present the results of the spectral transmittance and reflectance of a SiO2/TiO2 1D photonic crystal deposited by Radio Frequency sputtering on a flexible polymeric substrate, which shows a blue-shift in its transmittance stopband proportional to the incidence angle when bent. An adjustable sample holder was designed to regulate the bending and keep the sample in a bent condition. Different angles of incidence were also achieved through variable angle reflectance, where an increase in incidence angle led to the blue-shift and narrowing of the transmittance stopband. We addressed the sample's resistance against bending wear and tear by comparing the transmittance spectra acquired for the flat sample before and after the measurements made in bent configurations. An important stability has been observed.

The experimental study of the oxidation of a blend containing n-decane and a large unsaturated ester, methyl oleate, was performed in a jet-stirred reactor over a wide range of temperature covering both low and high temperature regions (550-1100 K), at a residence time of 1.5 s, at quasi atmospheric pressure with high dilution in helium (n-decane and methyl oleate inlet mole fractions of 1.48 × 10-3 and 5.2 × 10-4) and under stoichiometric conditions. The formation of numerous reaction products was observed. At low and intermediate temperatures, the oxidation of the blend led to the formation of species containing oxygen atoms like cyclic ethers, aldehydes and ketones deriving from n-decane and methyl oleate. At higher temperature, these species were not formed anymore and the presence of unsaturated species was observed. Because of the presence of the double bond in the middle of the alkyl chain of methyl oleate, the formation of some specific products was observed. These species are dienes and esters with two double bonds produced from the decomposition paths of methyl oleate and some species obtained from the addition of H-atoms, OH and HO2 radicals to the double bond. Experimental results were compared with former results of the oxidation of a blend of n-decane and methyl palmitate performed under similar conditions. This comparison allowed highlighting the similarities and the differences in the reactivity and in the distribution of the reaction products for the oxidation of large saturated and unsaturated esters.

The hot pressing process for 100% coriander-based fiberboards was optimized using an induction RocTool system, which offers rapid mold heating and cooling. The fiberboards were made with deoiled press cake as a proteic binder and extrusion-refined straw as reinforcement. A Doehlert’s experimental design evaluated the influence of pressure (10-50 MPa), molding time (60-300 s), and mold temperature (155-205°C) on fiberboard properties, energy consumption, cost, and environmental impact. The results showed that the RocTool device allows better temperature control during shaping, resulting in exacerbated adhesive properties for proteins. Using the isoresponse curves, optimal hot pressing conditions were 35 MPa, 300 s, and 205°C, corresponding to a 40.6 MPa flexural strength. However, it was observed that to achieve a MDF-like fiberboard with minimal production cost, much less restrictive molding conditions were sufficient, i.e., 32.5 MPa, 170 s, and 160°C. The study revealed that maximum thermopressing conditions emitted 3.87 kg of CO2 eq., while conditions leading to the MDF-like board reduced emissions to 1.45 kg CO2 eq., resulting in a more environmentally-friendly material.

AbstractLifetime techniques are frequently used to identify transition metals and to quantify their concentrations in silicon1-3. One of the most common contaminations is iron1,4,5. Dissolved iron exists in many defect configurations, the most prominent two are the interstitial Iron (Fei) and the Iron Boron Pairs (FeB). These defects are investigated on intentionally iron contaminated silicon samples by means of injection dependent lifetime spectroscopy (IDLS) and temperature and injection dependent lifetime spectroscopy (T-IDLS). In this paper we present IDLS and T-IDLS measurements, explain the basics of the used evaluation technique and compare the results.

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La croissance secondaire est à l'origine de l'accumulation de biomasse pérenne par les arbres et détermine en partie la capacité des écosystèmes forestiers à stocker du carbone. Cependant, les contraintes environnementales sur la croissance en milieu méditerranéen sont encore mal décrites et nous ne savons pas comment les changements climatiques futurs vont les modifier. L'objectif de la thèse est de déterminer, principalement à partir de l'étude de l'allocation du carbone à la croissance secondaire, les réponses fonctionnelles saisonnières et interannuelles du chêne vert (Quercus ilex L.) aux variations climatiques en région méditerranéenne. L'utilisation de différentes approches expérimentales, à des échelles spatiales allant du cerne à l'écosystème et à des échelles temporelles allant de la journée à plusieurs dizaines d'années, a permis de mettre en évidence l'effet de différentes contraintes environnementales (disponibilité en eau, réchauffement de la température, et densité du peuplement) sur la croissance secondaire et la composition isotopique du cerne. L'étude de la phénologie de la croissance montre que celle-ci est contrôlée directement par les températures hivernales et le déficit hydrique, plus que par la disponibilité en éléments carbonés issus de la photosynthèse. De 1968 à 2013, les changements climatiques ont entrainé une contrainte hydrique de plus en plus précoce qui s'est trouvée compensée par un début de croissance initié plus tôt dans l'année, sous l'effet du réchauffement des températures hivernales, et une meilleure efficacité d'utilisation de l'eau, sous l'effet de l'augmentation de la concentration en CO2 atmosphérique. La réduction de la mortalité et l'augmentation de la croissance observée dans des parcelles éclaircies montre que cette pratique sylvicole permet de préparer les taillis de chêne vert à l'intensification de la sècheresse prévue pour la région méditerranéenne. Tree secondary growth is responsible for woody biomass accumulation and is a major component of carbon storage in forest ecosystems. Environmental constraints on secondary growth in Mediterranean ecosystems must, however, be described in more to details to better understand how they will be modified by climate change. This dissertation aims at studying the functional responses of Mediterranean holm oak (Quercus ilex) to seasonal and inter-annual climate variations through the study of carbon allocation to secondary growth. Different experimental approaches, at spatial scales ranging from tree rings to the ecosystem and at temporal scales from the day to several decades, were used to identify the main environmental constraints (water availability, temperature warming, competition) to secondary growth and carbon isotopic composition of tree rings. The phenology of stem growth shows evidence for a direct environmental control on annual growth by winter temperature and summer drought that is more limiting than the carbon supply from photosynthesis. Climate change from 1968 to 2013 resulted in earlier water limitation on secondary growth, which was compensated by earlier growth onset, due to warmer winter temperature, and higher water use efficiency, due to increased atmospheric CO2 concentration. Thinning reduced tree mortality and increased stem growth, so thinning management in old holm oak coppices could prepare the ecosystem to better withstand the increasing drought forecasted for the Mediterranean region.