Search results for "Quantitative Biology"
showing 10 items of 1025 documents
Chronic neural probe for simultaneous recording of single-unit, multi-unit, and local field potential activity from multiple brain sites
2017
Drug resistant focal epilepsy can be treated by resecting the epileptic focus requiring a precise focus localisation using stereoelectroencephalography (SEEG) probes. As commercial SEEG probes offer only a limited spatial resolution, probes of higher channel count and design freedom enabling the incorporation of macro and microelectrodes would help increasing spatial resolution and thus open new perspectives for investigating mechanisms underlying focal epilepsy and its treatment. This work describes a new fabrication process for SEEG probes with materials and dimensions similar to clinical probes enabling recording single neuron activity at high spatial resolution.Polyimide is used as a bi…
Triggering a transient organo-gelation system in a chemically active solvent
2021
A transient organo-gelation system with spatiotemporal dynamic properties is described. Here, the solvent actively controls a complex set of equilibria that underpin the dynamic assembly event. The observed metastability is due to the in situ formation of a secondary solvent, acting as an antagonist against the primary solvent of the organogel. peerReviewed
The adsorption of water vapor on super absorbent product at low temperatures and low mass.
2006
The adsorption isotherms of water vapor on super absorbent product have the same form of type III isotherm at ambient temperature with the hysteresis phenomena. For temperatures lower than ambient, the isotherms become deformed because of the chains effect. The polymer is characterized by a multilayer adsorption, which occurs before a full-course is complete. During adsorption reactions, the polymer undergoes rearrangement polymeric network, which results from a cooperative diffusion of the water molecules and from a chain spacing followed by an expansion of the polymeric network. Three types of water molecules adsorbed on polymer were identified: strongly dependent water, adsorbed water, a…
Effect of fixation target on the contrast sensitivity in the foveal and parafoveal area
2017
Purpose To determine the influence on the contrast sensitivity when the stimulus contains a fixation target in two retinal locations, foveal and parafoveal. Methods Four young adults with 0.0 logMar acuity participated in this study. The stimulus was based on vertical sinusoidal gratings masked by a circular (for foveal area) or a ring (for parafoveal area). To increase the luminance resolution of the display a bit-stealing technique was used. Four different sets of stimuli were generated, two for exploring the foveal sensitivity and two for the parafoveal area. The difference between the sets designed for the same area was the presence, or absence, of a fixation target (a white cross) in t…
Water Fluxes in Polymeric Membranes for Desalination via Membrane Distillation
2010
Membrane distillation is an emerging technique for seawater desalination. Hydrophobic polymeric membranes are used to separate the solute‐free water vapour from the hot solution. Vapour fluxes of commercial polymeric membranes were measured in various conditions, i.e. natural and forced convection and vacuum. Vapour fluxes were also predicted with models and compared with experimentals. Higher fluxes were recorded in vacuum conditions.
Dose calculation in biological samples in a mixed neutron-gamma field at the TRIGA reactor of the University of Mainz
2010
To establish Boron Neutron Capture Therapy (BNCT) for non-resectable liver metastases and for in vitro experiments at the TRIGA Mark II reactor at the University of Mainz, Germany, it is necessary to have a reliable dose monitoring system. The in vitro experiments are used to determine the relative biological effectiveness (RBE) of liver and cancer cells in our mixed neutron and gamma fi eld. We work with alanine detectors in combination with Monte Carlo simulations, where we can measure and characterize the dose. To verify our calculations we perform neutron fl ux measurements using gold foil activation and pin-diodes . Material and methods . When L- α -alanine is irradiated with ionizing …
Bis[S-hexyl 3-(thiophen-2-ylmethylidene)dithiocarbazato-κ2N3,S]palladium(II)
2016
In the title complex, [Pd(C12H17N2S3)2], the PdIIatom exhibits a square-planar coordination geometry with theN,S-chelating ligands arranged in atransconfiguration. Intramolecular C—H...S hydrogen bonds are observed. In the crystal, molecules are linked by weak C—H...N hydrogen-bond interactions, forming chains parallel to thebaxis.
Adsorption and desorption surface dynamics of gaseous adsorbate on silicate-1 by molecular dynamics simulation
2013
The dynamics of adsorption and desorption of gaseous molecules on the external surface of a crystal and a membrane of zeolite silicate-1 is investigated by molecular dynamics simulation. The gases ...
Monte Carlo Simulations of Parallel Charged Platelets as an Approach to Tactoid Formation in Clay
2013
The free energy of interaction between parallel charged platelets with divalent counterions has been calculated using Monte Carlo simulations to investigate the electrostatic effects on aggregation. The platelets are primarily intended to represent clay particles. With divalent counterions, the free energy for two platelets or two tactoids (clusters of parallel platelets) shows a minimum at a short separation due to the attraction caused by ion-ion correlations. In a salt-free system, the free energy of interaction has a long-range repulsive tail beyond the minimum. The repulsion increases for tactoids with larger aggregation numbers, whereas the depth of the free-energy minimum is graduall…
Pressure- and temperature-induced valence tautomeric interconversion in a o-dioxolene adduct of a cobalt-tetraazamacrocycle complex
2001
An electronic switch at the molecular level has been realized by using a class of ionic compounds of the formula [Co(L)(diox)]Y (L = tetraazamacrocyclic ligand, Y = mononegative anion). Such compounds undergo temperature- and pressure-induced intramolecular one-electron transfer equilibria. The transition temperature of interconversion varies with the nature of the counterions Y (Y = PF6, BPh4, I). Surprisingly the effect of the anion on the transition temperature is not only governed by its volume but also by its coulombic interaction.