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Longitudinal multi-plot studies of nest architecture in non-domesticated birds are rare. Here we report the results of an 18-year multi-plot study that compared heights of fresh female-built nests in Corsican Great Tits (Parus major) and Blue Tits (Cyanistes caeruleus ogliastrae). Boxes with relatively small nest-chambers were erected in a landscape with habitat patches that were either dominated by food-rich broad-leaved deciduous oaks (Quercus humilis) or food-poor evergreen oaks (Quercus ilex). Nest height tended to change with oak habitat type in a species-specific manner. Great Tits built shallower nests than Blue Tits supporting the published findings from other geographic regions (Poland, UK, southern mainland France). Potential impacts of local climate factors and risks related to nest predation on the species-specific expression of the size of nests are discussed.

Comparative studies predicted or reported weaker or stronger positive relationships between nest size and body size both within and across avian species. Here we show that in relatively small nest-chambers, larger Great Tits (Parus major) build shallower nests than smaller Blue Tits (Cyanistes caeruleus). Our results from the Mediterranean region support findings from published studies that were conducted at more northerly latitudes (UK and Poland). Potential impacts of the local climate and predation risks on the species-specific expression of the size of fresh nests are discussed.

The electro-deposition and dissolution of MnO2 is studied for its potential utilization in hybrid supercapacitors. A commercially available graphene powder is used as high surface area substrate and capacitive type electrode. An aqueous electrolyte composed of 0.5 M H2SO4 + 0.5 M MnSO4 is used. The deposition-dissolution reaction of MnO2 is shown to provide the bulk of the charge storable in the battery type electrode. Furthermore, the potential window of stability of this electrode reaction is compatible with the aqueous electrolyte. Two complete systems were assembled and tested for their charge/discharge behavior. It is shown that energy and power densities of 25 Wh kg[?]1 and 980 W kg[?]1, respectively, can be achieved for at least 5000 cycles. Limitations of the system in terms of cycle numbers and electrolyte volume are discussed in more detail. The electrolyte volume to electrode mass ratio is shown to be a critical factor in determining the charge/discharge cycle number of the device. This is believed to be due to the fact that the efficiency of the MnO2 electro-dissolution/deposition process is less than 100%. This, in turn, could result in gradual pH changes and a lower Mn2+ concentration in the electrolyte during continues charging and discharging. This eventually results in lowering the energy and power density of the system. However, it is shown that an energy density of 25 Wh kg[?]1 is achievable, thus being comparable with similar hybrid systems.

The principle of feasibility of a hybrid super-capacitor, based on graphene and the electrochemical deposition and dissolution of "MnO2", is demonstrated. For this system, a composite graphene electrode is used as the capacitive electrode. Graphene is also used in the battery type electrode, where it serves as substrate for the in-situ electrochemical deposition and dissolution of "MnO2". The electrochemical deposition and dissolution reaction provides the bulk of the charge storable in the battery type electrode. The characteristics of the two electrodes are discussed showing that their respective potential windows of stabilities are compatible with the aqueous the electrolyte. Subsequently, two hybrid systems are assembled and subjected to long charge/discharge cycles. One assembly displays an energy density of 34 and 25 Wh kg-1 after the first and 5000th cycle, respectively.

Lead dioxide thin films and nanowires were prepared by electrochemical deposition using a solution. is deposited at pH 5.0, while is obtained at pH 0.0. Using pH 5.0, films of different thicknesses and nanowires of different lengths were prepared by varying the deposition charge . The electrochemical reactivity of is strongly dependent on the structure of the deposit. For nanowires and thin films, only and 2-3% of the deposited material is electrochemically active, respectively. A detailed analysis of the reactivity of with the deposition of with the deposition charge was performed by assuming that , where is the percentage of reactive matter, and and are adjustable parameters. For nanowires, and the reactivity is almost independent of the deposition charge (and length of the nanowires). In contrast, for thin films, and the reactivity decreases rapidly with the reciprocal of the deposition charge. After , nanowires and thin films exhibit almost the same activity.

Ordered lead dioxide nanowires were synthesized by electrodeposition through an alumina porous membrane. The reduction charge recorded on the first cyclic voltammogram in 1M H2SO4 is about three times larger for PbO2 nanowires compared to PbO2 thin film.

A small family of novel basic leucine zipper proteins that includes abscisic acid (ABA)-INSENSITIVE 5 (ABI5) binds to the promoter region of the lea class gene Dc3. The factors, referred to as AtDPBFs (Arabidopsis Dc3 promoter-binding factors), were isolated from an immature seed cDNA library. AtDPBFs bind to the embryo specification and ABA-responsive elements in the Dc3 promoter and are unique in that they can interact with cis-elements that do not contain the ACGT core sequence required for the binding of most other plant basic leucine zipper proteins. Analysis of full-length cDNAs showed that at least five different Dc3 promoter-binding factors are present in Arabidopsis seeds; one of these, AtDPBF-1, is identical to ABI5. As expected, AtDPBF-1/ABI5 mRNA is inducible by exogenous ABA in seedlings. Despite the near identity in their basic domains, AtDPBFs are distinct in their DNA-binding, dimerization, and transcriptional activity.

Endocrinological studies have contributed considerably to the development of theory concerning the proximate aspects of the timing of reproduction. In non–domesticated, avian species, the relative importance of the photoperiodic and non–photoperiodic factors influencing later stages of the breeding cycle, such as the onset of egg laying, remains unclear because egg laying is difficult to obtain with captive populations and laboratory experiments of breeding are rarely carried out in the framework of long–term field studies. We set up a special experimental design such that captive Mediterranean blue tits (Parus caeruleus) can breed with success in large outdoor aviaries at similar latitudes and altitudes to their wild counterparts. Here we demonstrate experimentally that the non–photoperiodic factors responsible for large and consistent differences in the expression of natural breeding responses between three captive outdoor blue tit populations are ignored during long–day treatment. Based on these findings, an evolutionary explanation is provided for why the relative importance of the non–photoperiodic factors decreases with the progress of the season. The hypothesis can explain observed maladapted breeding dates in free–living populations and could possibly be used to increase the success of breeding programmes with some endangered, captive, non–domesticated, photoperiodic species.

Risk taking, as is any other phenotypic and/or behavioural trait, is determined by proximate constraints related to time or resource availability and by evolutionary adaptive restraints related to the differences in the costs of risk taking and its benefits in terms of fitness. Because risk taking is influenced by many confounding variables related to experimental design, environment, parents and offspring, few field studies have been reported which unambiguously separate the effects of restraints from those of constraints. We compared parental risk taking in blue tits (Parus caeruleus) during brood defence towards a nest predator in broods with experimentally reduced and natural egg–hatching success leaving the original number of eggs in the nest. The experimentally reduced broods had more time or resources available and lower risk–taking benefits compared to the control broods. ‘Constraint’ would predict more risk taking in broods having experimentally reduced egg–hatching success, whereas ‘restraint’ would predict the opposite effect with more risk taking in broods with natural egg–hatching success. We report, to our knowledge, the first field study experimentally demonstrating a brood defence restraint in response to reduced egg–hatching success. This demonstration was only possible after controlling for more than 20 potential confounding variables showing once more how complicated it is to separate proximate from evolutionary levels of analyses in natural populations.

Selected channel-lining cysteine mutants from the M2 segment of rat α1 γ-aminobutyric acid (GABA) type A receptor subunit, at positions 257, 261, 264, and 272 were co-expressed with β1 and γ2 subunits in Xenopusoocytes. They generated functional receptors displaying conductance and response to both GABA and picrotoxinin similar to the wild type α1β1γ2 receptor. Three chemically reactive affinity probes derived from non-competitive blockers were synthesized to react with the engineered cysteines: 1) dithiane bis-sulfone derivative modified by an isothiocyanate function (probe A); 2) fiprole derivatives modified by an α-chloroketone (probe B) and α-bromoketone (probe C) moiety. These probes blocked the GABA-induced currents on all receptors. This blockade could be fully reversed by a washing procedure on the wild type, the α1T261Cβ1γ2 and α1L264Cβ1γ2 mutant receptors. In contrast, an irreversible effect was observed for all three probes on both α1V257Cβ1γ2 and α1S272Cβ1γ2 mutant receptors. This effect was probe concentration-dependent and could be abolished by picrotoxinin and/or t-butyl bicyclophosphorothionate. These data indicate a major interaction of non-competitive blockers at position 257 of the presumed M2 segment of rat α1 subunit but also suggest an interaction at the more extracellular position 272.

A complete understanding of the spatio–temporal variation in phenotypic traits in natural populations requires a combination long–term field studies with experiments using captive animals. Field studies allow the formulation of realistic hypotheses, but have the disadvantage that they do not allow the complete control of many potential confounding variables. Studies with captive animals allow tests of hypotheses that cannot be examined in the field, but have the disadvantage that artificial environments may provoke abnormal behaviour. Long–term studies that follow simultaneously captive and wild bird populations are rare. In a study lasting several years, we show here the unexpected patterns that two populations with a similar breeding time in the wild have non–overlapping breeding times in outdoor aviaries, and that two wild populations separated by a short geographical distance show differences in the expression of natural behaviour in captivity. The experimental design used is exceptional in the sense that the captive populations were held at similar latitudes and altitudes as the wild populations. Our case study shows that studies with captive animals can lead to wrong conclusions if they are carried out without population field studies, and without knowledge of the natural habits and habitats of the species involved. To examine the reliability of experiments with captive animals, comparisons with findings from population field studies are essential.

High variation in laying date and clutch size of the blue tit between a Mediterranean mixed habitat on the mainland, southern France, and a sclerophyllous habitat on the island of Corsica is hypothesized to be related to differences in the food supply. The diet of the nestlings and feeding frequencies were studied using camera nestboxes and electronic chronographs. Food items brought to the nestlings were much more diverse on Corsica than on the mainland, including many fewer caterpillars and a wider range of taxa. However, when expressed as a volume index, prey items were on average larger on Corsica than on the mainland. Feeding frequencies were significantly lower on Corsica. A good correlation was found in both habitats between laying date and the caterpillar peak date, although both the leafing development of oaks and the peak of abundance of caterpillars occurred 3 weeks later in the Corsican sclerophyllous trees than in the mainland deciduous ones. Differences in the feeding ecology of tits between the two habitats are discussed in the light of the evergreen habit, which means that only 30% of leaves are available for phyllophagous insects instead of 100% in deciduous trees. the combination of a late and low food supply in evergreen trees is the best explanation for the differences in breeding traits betwen the two populations.

We investigate whether a mosaic of habitats of different quality functions as a source-sink system for the Blue Tit Parus caeruleusL. Breeding parameters, especially laying date, clutch size and breeding success have been studied in relation to the food supply in three habitats: two habitats, one rich and one poor, next to each other on the mainland (southern France) and one poor habitat on the island of Corsica. Food resources are more abundant and are available earlier in the season in the rich habitat than in both the mainland and the island poor habitats. The timing of breeding is nicely timed on the food peak of abundance in the rich mainland habitat and in the poor insular one but tits are mistimed in the poor mainland habitat because they start to breed too early in relation to food availability. Such patterns strongly suggest that the rich mainland habitat where birds produce many fledglings functions as a source from which birds emigrate in the poor habitat which functions as a sink. These birds which are genetically programmed to breed in the source habitat become mistimed in the sink. Tits on Corsica which are isolated from any mainland population have adjusted their breeding traits on the local patterns of food availability and abundance. This hypothesis is supported by the existence of a strong genetic component of laying date which has been experimentally proved.

Abstract: In an attempt to test predictions of the optimisation hypothesis of life history traits in birds, we estimated fitness consequences of brood size manipulations. Experiments were carried out over a period of 4 years in a Mediterranean population of blue tits Parus caeruleus which is confronted with a particular set of environmental constraints. Effects of brood size manipulation were investigated in relation to year-to-year variation in environmental conditions, especially caterpillar abundance. There was a strong variation in the effects of brood size manipulation depending on year. Most effects were on offspring quality (fledging mass, tarsus length). The absolute number of recruits did not significantly differ among categories (reduced, control, enlarged broods) but varied considerably among years. Females recruited from enlarged broods were of lower quality, started to breed later and laid fewer eggs than those recruited from control and reduced broods. Neither parental survival nor reproductive performances of adults in year n + 1 was affected by brood size manipulation in year n. Thus there was no evidence for a cost of reproduction in this population. Since the number of recruits did not depend on brood size manipulation (recruitment rates were higher in reduced broods), but recruits from reduced broods were of better quality compared with other groups, we conclude that adults lay a clutch that is larger than that which is predicted by the optimisation hypothesis. Producing more young could incur some penalties because offspring from large broods are of lower quality and less likely to recruit in the population. Two possible reasons why decision rules in this population seem to be suboptimal are discussed.

There are striking differences in life-history traits associated with reproduction, between an insular population of the blue-tit and one on the nearby mainland. In order to test the extent to which these differences are genetic, two samples of birds, one from Corsica and one from mainland southern France, were hand-raised. These birds bred subsequently in aviaries at Montpellier during three consecutive years, at the same date and in the same way as did the natural populations from which they came. It is concluded that the difference in laying-date between the two samples has a genetic basis. The adaptation to each particular set of environmental conditions is discussed.

Females of the Blue Tit were observed to bring plant materials to their nests on Corsica. The timing of the visits with green moss and leaves, late evening, suggests that their most probable function is the insulation of the nest. Another likely function is the protection against parasites and pathogens.

Abstract: The detrimental effects of ectoparasites on the breeding success of birds have been especially well demonstrated in the case of ectoparasites that affect both chicks and their parents. Since blowfly larvae of the genus Protocalliphora attack only nestling birds, they represent a good model for testing the consequences of parasitism on nestlings. A Corsican population of blue tit suffers extremely high rates of infestation by blowflies, which are suspected to negatively affect young birds. Comparing experimentally deparasitized (treated) and naturally infested (control) broods, we showed that the attack by Protocalliphora causes anaemia and an important disturbance to the chicks. Therefore, we expected that these effects would have a negative impact on body condition and survival in the infested broods. Although we did not find any effect of treatment on fledging success, our predictions were confirmed by lower growth rate, body mass at fledging and tarsus length at fledging in the control compared with the treated group. This suggests that in this population, blowflies decrease the probability of recruitment of young blue tits.

The electro-deposition and dissolution of MnO2is studied for its potential utilization in hybrid supercapacitors. A commercially available graphene powder is used as high surface area substrate and capacitive type electrode. An aqueous electrolyte composed of 0.5 M H2SO4+ 0.5 M MnSO4is used. The deposition-dissolution reaction of MnO2is shown to provide the bulk of the charge storable in the battery type electrode. Furthermore, the potential window of stability of this electrode reaction is compatible with the aqueous electrolyte. Two complete systems were assembled and tested for their charge/discharge behavior. It is shown that energy and power densities of 25 Wh kg−1and 980 W kg−1, respectively, can be achieved for at least 5000 cycles. Limitations of the system in terms of cycle numbers and electrolyte volume are discussed in more detail. The electrolyte volume to electrode mass ratio is shown to be a critical factor in determining the charge/discharge cycle number of the device. This is believed to be due to the fact that the efficiency of the MnO2electro-dissolution/deposition process is less than 100%. This, in turn, could result in gradual pH changes and a lower Mn2+concentration in the electrolyte during continues charging and discharging. This eventually results in lowering the energy and power density of the system. However, it is shown that an energy density of 25 Wh kg−1is achievable, thus being comparable with similar hybrid systems.

The principle of feasibility of a hybrid super-capacitor, based on graphene and the electrochemical deposition and dissolution of "MnO2", is demonstrated. For this system, a composite graphene electrode is used as the capacitive electrode. Graphene is also used in the battery type electrode, where it serves as substrate for the in-situ electrochemical deposition and dissolution of "MnO2". The electrochemical deposition and dissolution reaction provides the bulk of the charge storable in the battery type electrode. The characteristics of the two electrodes are discussed showing that their respective potential windows of stabilities are compatible with the aqueous the electrolyte. Subsequently, two hybrid systems are assembled and subjected to long charge/discharge cycles. One assembly displays an energy density of 34 and 25 Wh kg-1 after the first and 5000th cycle, respectively.

Lead dioxide thin films and nanowires were prepared by electrochemical deposition using a 0.1MPb(NO3)2solution. α-PbO2is deposited at pH 5.0, while β-PbO2is obtained at pH 0.0. Using pH 5.0, films of different thicknesses and nanowires of different lengths were prepared by varying the deposition charge (Qdep). The electrochemical reactivity of PbO2is strongly dependent on the structure of the deposit. For PbO2nanowires and thin films, only ∼6to7%and 2–3% of the deposited material is electrochemically active, respectively. A detailed analysis of the reactivity of PbO2with the deposition of PbO2with the deposition charge was performed by assuming that r=aQdepb, where ris the percentage of reactive matter, and aand bare adjustable parameters. For PbO2nanowires, b=−0.2and the reactivity is almost independent of the deposition charge (and length of the nanowires). In contrast, for PbO2thin films, b=−0.65and the reactivity decreases rapidly with the reciprocal of the deposition charge. After 10cycles, PbO2nanowires and thin films exhibit almost the same activity.

Ordered lead dioxide nanowires were synthesized by electrodeposition through an alumina porous membrane. The reduction charge recorded on the first cyclic voltammogram in 1M H2SO4 is about three times larger for PbO2 nanowires compared to PbO2 thin film.

Few empirical studies of bird populations have examined in detail how proximate and ultimate factors determine phenotypic variation in relation to small-scale environmental variation. This question has been addressed in the Mediterranean region, using blue tit (Parus caeruleus) populations living in habitat patches dominated either by deciduous (Quercus humilis) or evergreen (Q. ilex) oaks, which strongly differ in the timing and abundance of food resources. Our aim was threefold: 1) to analyse phenotypic variation and local differentiation of fitness-related life history traits on the scale of habitat mosaics within two different landscapes, one in mainland southern Prance and one on the island of Corsica; 2) to examine to what extent phenotypic variation is an ultimate response to local selection regimes and results in local adaptation; 3) to investigate whether phenotypic variation correlates with the genetic structure of populations. In the mainland landscape, where tits are assumed to disperse freely across habitat patches, little local differentiation of breeding traits has been found within a range of ca40 km, suggesting gene swamping between populations. A molecular genetics study of populations within this landscape supported the hypothesis of a source-sink population structure with more birds immigrating from deciduous habitat patches to evergreen ones than the reverse. In a similar geographic configuration of habitats in Corsica, there was a higher phenotypic variation and a higher degree of population differentiation on a scale which is usually smaller than the dispersal range of blue tits. This difference between the mainland and Corsica is interpreted as resulting from reduced dispersal ranges of island birds and supports the divergence-with-gene-flow model of speciation.