Search results for "PICO"
showing 10 items of 343 documents
Injection and ultrafast regeneration in dye-sensitized solar cells
2014
Injection of an electron from the excited dye molecule to the semiconductor is the initial charge separation step in dye-sensitized solar cells (DSC's). Though the dynamics of the forward injection process has been widely studied, the results reported so far are controversial, especially for complete DSC's. In this work, the electron injection in titanium dioxide (TiO2) films sensitized with ruthenium bipyridyl dyes N3 and N719 was studied both in neat solvent and in a typical iodide/triiodide (I-/I3 -) DSC electrolyte. Transient absorption (TA) spectroscopy was used to monitor both the formation of the oxidized dye and the arrival of injected electrons to the conduction band of TiO2. Emiss…
Substitution of the laser borane anti-B18H22 with pyridine: a structural and photophysical study of some unusually structured macropolyhedral boron h…
2018
Reaction of anti-B18H221 with pyridine in neutral solvents gives sparingly soluble B16H18-3',8'-Py23a as the major product (ca. 53%) and B18H20-6',9'-Py22 (ca. 15%) as the minor product, with small quantities of B18H20-8'-Py 4 (ca. 1%) also being formed. The three new compounds 2, 3a and 4 are characterized by single-crystal X-ray diffraction analyses and by multinuclear multiple-resonance NMR spectroscopy. Compound 2 is of ten-vertex nido:ten-vertex arachno two-atoms-in-common architecture, long postulated for a species with borons-only cluster constitution, but previously elusive. Compound 3a is of unprecedented ten-vertex nido:eight-vertex arachno two-atoms-in-common architecture. The si…
The good, the bad and the ugly: Emys trinacris, Placobdella costata and Haemogregarina stepanowi in Sicily (Testudines, Annelida and Apicomplexa)
2016
Endemic Sicilian pond turtles Emys trinacris Fritz, Fattizzo, Guicking, Tripepi, Pennisi, Lenk, Joger et Wink were examined for the presence of haemogregarine parasites. The presence of haemogregarines, occurring mainly in the microgametocyte stage (13.2 ± 0.12 μm in length and 6.4 ± 0.52 μm in width), was observed in approximately 9% of the sampled E. trinacris. Based on the observed morphology and on the sequencing of nuclear 18S rDNA, we identified the parasite as Haemogregarina stepanowi Danilewsky, 1885. Morphometric study of uninfected and infected red blood cells has shown that H. stepanowi induces different changes in erythrocyte shape depending on the infective stage. The different…
The effects of meta-Topolin and benzyladenine on in vitro organogenesis from epicotyl cuttings of Troyer citrange (Citrus sinensis[L.] Osbeck ×Poncir…
2017
Citrus tristeza virus (CTV), worldwide considered as one of the worst disease affecting Citrus plants, produced great changes in citriculture, mainly because it made mandatory the turnover of the sensitive sour orange rootstock with virus resistant ones. Among them, Troyer citrange has become one of the most employed rootstocks, due to its CTV tolerance and to the positive characteristics induced to the scion fruit production. Unfortunately, in Italy, there is a scarcity of seed mother plants. Micropropagation can be a solution for this problem. Among the in vitro techniques allowing the production of good quality true-to-type plants, the regeneration from seedling epicotyl cuttings general…
Evaluation of fungicides and sterilants for potential application in the management of Fusarium wilt of banana
2007
Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Fusarium wilt is considered one of the most important diseases of bananas. The disease can only be managed by using resistant cultivars and by preventing its introduction into new fields. The objectives of this study were to evaluate newly available fungicides, in vitro and in vivo, for their efficacy against the responsible pathogen Fusarium oxysporum f.sp. cubense, and to evaluate surface sterilants that could be used for sterilization purposes. Of the fung…
Development of picoplankton during natural and enhanced mixing under late-winter ice
2014
We studied the development of autotrophic picophytoplankton and heterotrophic bacterioplankton during the tran- sition from winter ice cover to open water under natural and manipulated mixing conditions in eutrophic Lake Vesijarvi. During the melting of the snow and ice cover, a convection layer developed which eventually met the che- mocline at the interface between the oxic and anoxic water masses. However, in the years with mechanically enhanced mixing, the whole water column remained well oxygenated and the deepening of penetrative convection was facilitated. Stochastic variations in weather, primarily the thickness of the snow cover, likely determined the timing of picophytoplankton gr…
Sensitive measure of prevalence and parasitaemia of haemosporidia from European blackbird (Turdus merula) populations: value of PCR-RFLP and quantita…
2006
8 pages; International audience; Haemosporidian parasites are common in birds in which they act as an important selective pressure. While most studies so far have focused on the effect of their prevalence on host life-history traits, no study has measured the effect of parasitaemia. We developed molecular methods to detect, identify and quantify haemosporidia in 2 natural populations of the Blackbird Turdus merula. Three different parasite genotypes were found - 1 Haemoproteus and 2 Plasmodium. A PCR-RFLP screening revealed that only approximately 3% of blackbirds were free of parasites, compared to the 34% of uninfected birds estimated by blood smear screening. A quantitative PCR (q-PCR) a…
New national and regional bryophyte records, 36
2013
In the moss flora of Uruguay there are recorder ten species of genus Fissidens (Matteri, 2004). Three of them (F. macrobryoides, F. prionocheilos and F. vitreo-limbatus) are species incertae because the type material for the names not was located (Purssel, 2007). As part of project "Studies on Bryophytes in the Cone Sur (Systematic and Phylogeny)" some specimens recently collected in Uruguay were determinate as Fissidens asplenioides a no previously species recorded in this country. The presence of F. asplenioides in Uruguay complete the distribution range of the species in the cone Sur (is present in Argentina, Bolivia, Brazil, Chile and Paraguay). However, within the Neotropical region th…
Variation in timing of breeding of five woodpeckers in a primeval forest over 45 years: role of food, weather, and climate
2020
AbstractClimate warming could lead to ‘mis-matching’ of birds’ breeding times with availability of their invertebrate food resources. Fluctuating spring temperatures could influence variation in the commencement of egg-laying, as well as, in phenology of their resources (e.g., tree bud burst, appearance of folivorous caterpillars). We studied timing of Dendrocopos leucotos, Dendrocoptes medius, Dendrocopos major, Dryobates minor, and Picoides tridactylus breeding in, free of direct human intervention, strictly protected fragments of Białowieża Forest (Poland) in 1975–2019. We related their onset of breeding to inter-year variation in spring weather, trees’ bud burst and timing of folivorous…
Abilities of β-Estradiol to interact with chemotherapeutic drugs, signal transduction inhibitors and nutraceuticals and alter the proliferation of pa…
2019
Improving the effects of chemotherapy and reducing the side effects are important goals in cancer research. Various approaches have been examined to enhance the effectiveness of chemotherapy. For example, signal transduction inhibitors or hormonal based approaches have been included with chemo- or radio-therapy. MIA-PaCa-2 and BxPC-3 pancreatic ductal adenocarcinoma (PDAC) cells both express the estrogen receptor (ER). The effects of β-estradiol on the growth of PDAC cells has not been examined yet the ER is expressed in PDAC cells. We have examined the effects of combining β-estradiol with chemotherapeutic drugs, signal transcription inhibitors, natural products and nutraceuticals on PDAC.…