Search results for "GOLD"

Motion detection in goldfish investigated with the optomotor response is “color blind”

1996

AbstractThe action spectrum of the optomotor response in goldfish was measured to investigate which of the four cone types involved in color vision contributes to motion detection. In the dark-adapted state, the action spectrum showed a single maximum in the range of 500–520 nm, and resembled the rod spectral sensitivity function. Surprisingly, the action spectrum measured in the light-adapted state also revealed a single maximum only, located in the long wavelength range between 620 and 660 nm. A comparison with spectral sensitivity functions of the four cone types suggests that motion detection is dominated by the L-cone type. Using a two colored, “red-green” cylinder illuminated with two…

Temporal resolution and temporal transfer properties: gabaergic and cholinergic mechanisms.

2007

Temporal resolution is a basic property of the visual system and critically depends upon retinal temporal coding properties which are also of importance for directional coding. Whether the temporal coding properties for directional coding derive form inherent properties or critically depend upon the temporal coding mechanisms is unclear. Here, the influence of acetylcholine and GABA upon photopic temporal coding was investigated in goldfish, using flicker stimuli, in a behavioral and an electrophysiological (ERG) approach. The goldfish temporal resolution ability decreased from more than 90% correct choices at 20 Hz flicker frequency to about 65% at 45 Hz flicker frequency with a flicker fu…

Sabanejewia Aurata (De Filippi, 1863) Populations Management Decisions Support System for Rosci0132 (Olt River Basin)

2015

Abstract The ADONIS: CE was used to design a specific management model for the Sabanejewia aurata (De Filippi, 1863) populations. The proposed model is based on this species, in situ identified biological/ecological necessities in relation to the habitats, the conservation status indicators and appropriate management actions and the pressures and threats founded in the study area. Such on species, on habitats and on site based management system was done to complete this approach for ROSCI0132, the other fish species which are living there being treated already in this respect.

Inulin Coated Gold Nanoparticles As a Potential Tool For Cancer Therapy

2014

Gold nanoprobe-based detection of human telomerase reverse transcriptase (hTERT) Gene Expression

2015

Human Telomerase Reverse Transcriptase (hTERT) gene is expressed in all types of cancers, and it is considered as unique biomarker for early detection, monitoring and prognosis of different cancers. Routinely, the main techniques for detection of hTERT gene expression are based on enzymatic amplifications which need specified equipments, expert personnel and high cost and time. With regarding to the clinical importance of analysis of hTERT gene expression, we have developed a rapid, simple and low cost method which detects hTERT RNA target in 5 $\mu {\rm l}$ reaction scale using gold nanoprobes. The method is based on the inhibition of nanoparticle aggregation in the presence of ${\rm MgCl}…

Near-Infrared-Responsive Choline-Calix[4]arene-Gold Nanostructures for Potential Photothermal Cancer Treatment

2022

The development of novel chemical approaches for the fabrication of gold nanostructures with localized surface plasmon resonance (LSPR) falling in the near-infrared (NIR) region is one challenging topic in nanomaterials science. Due to their optical and photothermal properties triggered by light excitation in the therapeutic window (λmax = 650-1300 nm), gold-based nanostructures are appealing candidates in anticancer nanomedicine. Here, we report a novel method to prepare water-dispersible gold nanostructures with NIR-LSPR (λmax = 600-1000 nm) properties. The gold nanostructures were achieved in a single step by an unconventional method using NADH as a reducing agent and an amphiphilic chol…

A coumarin based gold(I)-alkynyl complex: a new class of supramolecular hydrogelators

2015

A phosphine-gold(I)-alkynyl-coumarin complex, [Au{7-(prop-2-ine-1-yloxy)-1-benzopyran-2-one}- (DAPTA)] (1), was synthesized and the formation of long luminescent fibers in solution was characterized via fluorescence microscopy and dynamic light scattering. The fibers presented strong blue and green luminescence, suggesting that the gold(I) in the complex increased intersystem crossing due to the heavy atom effect, resulting in a significant increase in triplet emission. The X-ray structure of the fibers indicates that both aurophilic, π–π interactions and hydrogen bonding contribute to their formation in aqueous solvents. peerReviewed

Persistence of oxidation state III of gold in thione coordination

2017

Ligands N,N'-tetramethylthiourea and 2-mercapto-1-methyl-imidazole form stable Au(III) complexes [AuCl3(N,N'-tetramethylthiourea)] (1) and [AuCl3(2-mercapto-1-methyl-imidazole)] (2) instead of reducing the Au(III) metal center into Au(I), which would be typical for the attachment of sulfur donors. Compounds 1 and 2 were characterized by spectroscopic methods and by X-ray crystallography. The spectroscopic details were explained by simulation of the UV-Vis spectra via the TD-DFT method. Additionally, computational DFT studies were performed in order to find the reason for the unusual oxidation state in the crystalline materials. The preference for Au(III) can be explained via various weak in…

COUPLING ELECTROCHEMISTRY TO ELECTROSPRAY: A NOVEL PREPARATION OF GOLD NANOSTRUCTURES

2013

nanoparticles on ITO (Indium tin oxide) coated glass using the electrospray (ESI) method Method:The starting point of this study is that the ESI/MS spectrum (Figure 1) of an ethanolic solution of HAuCl 4 shows a reduction process of Au (III) strongly dependent on the Cone Voltage (CV) values (20, 80, 150 V), affording to the ion at m/z 197 (Au+). Further, the decrease of the abundance of this ion at the highest cone voltage suggests the subsequent its reduction with the formation of Au 0 . Figure 1: ESI/MS spectra of an ethanolic solution of HAuCl4 at various cone voltages: Conclusion: Such experimental evidence leads us to use electrospray technique as a preparative tool to obtain the form…

Golden Power, emergenza Covid-19 e spirito del tempo

2020

L’articolo ha ad oggetto l’ampliamento dei poteri speciali del Governo in materia di aziende strategiche (c.d. Golden Power), previsto dalle disposizioni introdotte dal d.l. 8 aprile 2020 n. 23, nell’ambito della produzione normativa legata all’emergenza Covid-19. Nel procedere ad una un’analisi del testo, il lavoro si interroga sul rapporto fra la nuova disciplina e le esigenze poste dalla pandemia, e con il più generale “spirito del tempo” in tema di protezione dei sistemi economici nazionali. The article refers to the enlargement of governmental special powers regarding strategic business entities (so called Golden Power), according to the new rules issued by decree 8 April 2020 n. 23, w…