Search results for "clam"

Chlorohydrocarbons, PCB congeners, polychlorodioxins, furans and dibenzothiophenes in pine needles in the vicinity of a metal reclamation plant

1995

Abstract Chlorohydrocarbons, PCB congeners, polychlorodioxins, furans and dibenzothiophenes in pine needles in the vicinity of a metal reclamation plant were analyzed by GC/ECD and GC/MS. Wax and the rest of the needles were analyzed separately. As a rule the concentrations of α-HCH (0.5–13.6 ng/g), γ-HCH (0.4–7.3 ng/g), HCB (0.2–3.4 ng/g), PCB congeners (0.2–67 ng/g), PCDDs and PCDFs were higher in the older needles. The ratio of the concentration in the wax to the concentration in the rest of the needles was higher in the younger needles. The concentrations of PCB congeners, TeCDDs and TeCDFs were higher in the needles collected in the area nearest to the plant. The samples, obviously, co…

Investigation on Metal–Oxide Graphene Field-Effect Transistors With Clamped Geometries

2019

In this work, we report on the design, fabrication and characterization of Metal-Oxide Graphene Field-effect Transistors (MOGFETs) exploiting novel clamped gate geometries aimed at enhancing the device transconductance. The fabricated devices employ clamped metal contacts also for source and drain, as well as an optimized graphene meandered pattern for source contacting, in order to reduce parasitic resistance. Our experimental results demonstrate that MOGFETs with the proposed structure show improved high frequency performance, in terms of maximum available gain and transition frequency values, as a consequence of the higher equivalent transconductance obtained.

Electrophysiological and morphological properties of Cajal–Retzius cells with different ontogenetic origins

2010

International audience; The different origins of Cajal-Retzius cells (CRc) as well as their diverse molecular profile suggest that this cell type may represent different neuronal subpopulations. In order to investigate whether CRc from different origins show distinct functional or morphological characteristics we used transgenic Dbx1(cre);ROSA26(YFP) mice in which two subpopulations of CRc, originating from the septum and ventral pallium (VP) at the pallial-subpallial border (PSB), were permanently labeled by yellow fluorescent protein (YFP) expression. Electrophysiological properties of YFP(+) and YFP(-) CRc were investigated by whole-cell patch-clamp recordings, while a thorough somatoden…

Etude des propriétés de coordination de nouveaux ligands macrocycliques vis-à-vis de cations métalliques en vue de l'utilisation de leurs complexes p…

2011

Noninvasive medical imaging techniques such as single-photon emission computed tomography (SPECT) or positron emission tomography (PET), are valuable tools for the development and validation of new therapeutic molecules. That approach requires the conjugation of a radioactive source emitting either y-rays or positrons with a biological tracer (e.g. DOTATOC). Among the potentially useful radionuclides available, 111In3+ (SPECT), 64Cu2+, and 68Ga3+ (PET) have attracted increasing attention over the last years for medical applications. To minimize the in vivo release of the radioactive cation by transmetalation or transchelation with biological ligands, it is essential to trap selectively the …

A Study Using X-ray Absorption and Emission Spectroscopy of Dioxygen-Binding Xerogels Incorporating Cyclam Units Complexed with Copper Salts.

2005

X-ray absorption spectroscopy was used to elucidate how hybrid xerogels complexed with CuCl2 could reversibly bind molecular dioxygen. Difference EXAFS analyses at the Cu K-edge suggest that dioxygen could bridge two Cu atoms in a μ-η1:η1 peroxo-like conformation with unequal Cu···O distances. Only the short distance (RCu–O1 = 1.86 ± 0.01 A) was unambiguously determined and looks typical of a CuII site. The Cu···Cu internuclear distances would be rather long: RCu–Cu ≈ 4.0 A (3.9 A) for the oxygenated (oxygen-free) xerogels. Cl K-edge EXAFS spectra revealed the pre-existence in the oxygen-free xerogels of CuI sites with short Cl–Cu bonds (2.11 ± 0.03 A). Pentacoordinate CuII sites with a lon…

Microglia and α-synuclein implication in Parkinson's disease

2011

Age-related neurodegenerative disorders like Parkinson’s disease take an enormous toll on individuals and on society. Despite extensive efforts, Parkinson’s disease remains incurable and only very limited treatments exist. Indeed, Parkinson’s pathogenesis is still not clear and research on its molecular mechanisms is ongoing. In this study, we focused our interest on two abnormal events occurring in Parkinson’s patients, namely α-synuclein aggregation and microglial activation. We first investigated α-synuclein and its abnormal polymerisation. For this purpose, we developed novel methods, which allowed the in vitro production of different types of α-synuclein oligomers. Using highly sensiti…

Fusariose du cyclamen : travaux sur la lutte biologique. Phytoma-La défense des végétaux

2016

SPEIPM; Fusariose du cyclamen : travaux sur la lutte biologique. Phytoma-La défense des végétaux

Diversité génétique au sein de la forme spéciale cyclaminis de Fusarium oxysporum et recherche d’un marqueur spécifique

2014

Le cyclamen est la 3e plante fleurie la plus vendue en France. Une des maladies dommageables de cette culture est la fusariose, causée par Fusarium oxysporum f. sp. cyclaminis (FoCy). Cette forme spéciale, inféodée au cyclamen n’est pas différenciable des autres formes spéciales et souches saprophytes. En se développant dans le xylème, FoCy entraîne la mort de la plante. Quand les symptômes externes apparaissent, la plante est condamnée. La lutte chimique est inefficace, la lutte variétale est inexistante, et les mesures prophylactiques sont difficilement applicables. Pour détecter le pathogène précocement et améliorer la lutte, nous nous sommes intéressés à sa diversité génétique. Pour cel…

Fusariose du Cyclamen (FoCy): Détection préventive du risque et contrôle biologique

2013

Fusarium oxysporum f. sp. cyclaminis: Identification of specific molecular markers for improved disease prevention

2014

Fusarium oxysporum is a well-known soil-borne and ubiquitous fungus. The species includes a high diversity of saprophytic and pathogenic populations. The phytopathogenic ones are subdivided into formae speciales according to their host specificity. The forma specialis cyclaminis (FoCy) is causing Fusarium wilt only on cyclamen. It causes damages during the entire production line and can raise more than 50 % losses. FoCy is considered as the more destructive pathogen on cyclamen. To achieve a better understanding of the disease and a more efficient and eco-friendly way of control, we aim at finding a specific molecular marker allowing for early detection and quantification of the pathogen an…