Search results for "Allium"

Cathodoluminescence and structural studies of nitrided 3D gallium structures grown by MOCVD

2009

Abstract Cathodoluminescence (CL) spectrum imaging and grazing incidence X-ray diffraction (GIXRD) are employed to investigate nitride three-dimensional (3D) gallium structures. The metallic precursors are naturally obtained on a large variety of substrates by metal-organic chemical vapor deposition (CVD) with different shape/size controlled by the growth conditions, especially the temperature. These 3D metallic structures are subsequently exposed to a nitridation process in a conventional CVD reactor to form GaN nanocrystals, as confirmed by GIXRD measurements. CL spectroscopy shows visible light emission (2.5–2.8 eV) excited from the GaN in the 3D structures.

Chemical characterization of gallium droplets grown by LP-MOCVD.

2006

International audience; This study is concerned with the chemical characterization of metallic gallium droplets, obtained on silicon (1 0 0) substrates with a single growth step, by the LP-MOCVD technique with TMGa like precursor. These structures are characterized by SIMS, XPS and TEM. The analyses results lead to a structure proposition for the droplets. The core is composed of metastable metallic gallium with a non-negligible carbon quantity probably coming from incomplete precursor decomposition. The outer part, composed of gallium oxide maintains the structure stability. Covering of the substrate by a thin gallium layer of gallium compounds is observed.

Photoelectron spectroscopy of thin discontinuous metal films deposited onto a sapphire substrate

1995

Abstract The charging of small metallic clusters forming discontinuous gold and gallium films, condensed in vacuum onto an insulating substrate (sapphire), was experimentally studied by the method of ultraviolet photoelectron spectroscopy (UPS) for a photon energy of 5.4 eV. It seems that the charging is due to electron emission as well as to electron transfer from metal islands to the empty electron states in the metal-insulator interface.

Effetti della Densità d’Impianto e della Concimazione Solfo-Potassica sulla Qualita’ dell’Aglio Coltivato nella Sicilia Occidentale

2009

Low-level 809 nm GaAlAs laser irradiation increases the proliferation rate of human laryngeal carcinoma cells in vitro

2002

The aim of the study was to investigate the effect of low-level 809 nm laser irradiation on the proliferation rate of human larynx carcinoma cells in vitro. Epithelial tumor cells were obtained from a laryngeal carcinoma and cultured under standard conditions. For laser treatment the cells were spread on 96-well tissue culture plates. Sixty-six cell cultures were irradiated with an 809 nm GaAlAs laser. Another 66 served as controls. Power output was 10 mW(cw) and the time of exposure 75–300 s per well, corresponding to an energy fluence of 1.96–7.84 J/cm2. Subsequent to laser treatment, the cultures were incubated for 72 h. The proliferation rate was determined by means of fluorescence acti…

Radiolabelling and preliminary evaluation of 68Ga-tetrapyrrole derivatives as potential tracers for PET

2013

article i nfo Tetrapyrroles are multisided natural products which are of relevance in clinical medicine. Owing to their specific accumulation in tumour tissue, porphyrins, metalloporphyrins and chlorins have been used as in photodynamic therapy and optical imaging. Moreover, their specific uptake into inflammatory atheromatous plaques via LDL endocytosis has been reported. The present study is concerned with the synthesis of 68 Ga labelled porphyrin derivatives and an in vitro assessment of the utility of radiotracers in positron emission tomography. A set of five porphyrin derivatives were labelled using 68 Ga from a commercially obtained radionuclide generator. Dedicated post-processing o…

Cytotoxic effects of two extracts from garlic (Allium sativum L.) cultivars on the human squamous carcinoma cell line SCC-15

2018

Garlic (Allium sativum L., Alliaceae) has acquired a reputation as a therapeutic agent and herbal remedy to prevent and treat several pathologies. The aim of the present study was to determine the effect of two Allium sativum L. cultivars, Harnaś and Morado, on reactive oxygen species (ROS) production, viability and apoptotic process in human squamous carcinoma cell line SCC-15. The experiments were conducted on SCC-15 cell line exposed to increasing concentrations of garlic extracts of 0.062, 0.125, 0.250, 0.500 and 1.000 mg/mL. After the experiments, ROS formation, caspase-3 activity and neutral red uptake were measured in the cells, and in a collected medium lactate dehydrogenase (LDH) r…

Effects of garlic powders with varying alliin contents on hepatic drug metabolizing enzymes in rats

2003

International audience; The anticarcinogenic effect of garlic has been demonstrated in both epidemiologic and experimental studies. In this study, possible mechanisms involved in the anticarcinogenic effect of garlic consumption were assessed by determining its capacity to alter drug metabolizing enzymes, in relation with its alliin content. Rats were fed a diet for 2 weeks containing 5% garlic powders produced from bulbs grown on soils with different levels of sulfate fertilization and therefore containing differing amounts of alliin. Activities of several hepatic enzymes, which are important in carcinogen metabolism such cytochromes P450 (CYP) and phase II enzymes, were determined. Garlic…

Reduction of temperature coefficients in multicrystalline silicon solar cells after light-induced degradation

2015

This study focuses on the variations of the temperature coefficients after light-induced degradation (LID) of compensated multicrystalline silicon solar cells from three different ingots. The ingots have been chosen to see the effect of the compensation level, the resistivity and the impact of adding gallium to keep the resistivity as constant as possible along the ingot. The temperature coefficients of the efficiency experience a major decrease after LID on all ingots. We found that this decrease varies along the ingot height and does not correspond to the VOC drop. Moreover, no direct correlation with the interstitial oxygen concentration profiles could be seen.

Nuclear mean-square charge radii of63,64,66,68−82Ga nuclei: No anomalous behavior atN=32

2012

Collinear laser spectroscopy was performed on the ${}^{63,64,66,68\ensuremath{-}82}$Ga isotopes with neutron numbers from $N=32$ to $N=51$. These measurements were carried out at the ISOLDE radioactive ion beam facility at CERN. Here we present the nuclear mean-square charge radii extracted from the isotope shifts and, for the lighter isotopes, new spin and moment values. New ground-state nuclear spin and moments were extracted from the hyperfine spectra of ${}^{63,70}$Ga, measured on an atomic transition in the neutral atom. The ground-state spin of ${}^{63}$Ga is determined to be $I=3/2$. Analysis of the trend in the change in mean-square charge radii of the gallium isotopes demonstrates …