Biodegradation of lipids from olive oil mill wastewaters in a stationary basket bioreactor with immobilized Bacillus spp. cells - influence of internal diffusion.

The study is focused on the external and internal mass transfers of lipids during their biodegradation process in a bioreactor with stationary basket bed of immobilized Bacillus spp. cells. By means of the lipid mass balance for a single particle of biocatalyst, considering the kinetic model adapted for the immobilized bacterial cells, specific mathematical models have been developed to estimate their mass flows in the liquid boundary layer surrounding the particle and inside the particle.

Biomimetic chitosan-calcium phosphate composites with potential applications as bone substitutes: preparation and characterization.

A novel biomimetic technique for obtaining chitosan-calcium phosphates (Cs-CP) scaffolds are presented: calcium phosphates are precipitated from its precursors, CaCl(2) and NaH(2) PO(4) on the Cs matrix, under physiological conditions (human body temperature and body fluid pH; 37°C and pH = 7.2, respectively). Materials composition and structure have been confirmed by various techniques: elemental analysis, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM).

Inclusion complex of a new propiconazole derivative with β-cyclodextrin: NMR, ESI-MS and preliminary pharmacological studies.

A novel inclusion complex of the propiconazole nitrate (NO3PCZ) with β-cyclodextrin (β-CD) was prepared by treatment of propiconazole (PCZ) with an acidic nitrating agent. The formation of NO3PCZ and its inclusion complex with β-CD has been studied by NMR, ESI-MS, TGA, DSC methods. Using the undecoupled signal in the HMBC correlation spectra, almost identical coupling constants of CH from trizolic ring of PCZ and NO3PCZ compounds ((1)J(HC)3=207 Hz, (1)J(CH)5=214 Hz, for PCZ; (1)J(HC)3=208 Hz and (1)J(CH)5=215 Hz, for NO3PCZ) were determined, confirming that the geometry of the heterocyclic skeleton is identical in both the forms.

Enzyme-assisted purification of denatured atelocollagen, using pronase as scavenging agent.

Collagen liquid-crystal characteristics can be exploited in advanced applications, like microelectromechanical systems (MEMS), collagen-silica biohybrids or intelligent substrates for tissue engineering. Such applications necessarily require high purity of the collagen colloidal solutions, in terms of macromolecular unitary composition, which is equivalent to almost zero poydispersity. In this work a protocol for the enzyme-assisted removal of non-triple helical polypeptide entities in atelocollagen solutions was conceived, using pronase as scavenger, in the presence of poly(ethyleneglycol) (PEG 10000) as a crowding agent, trimethylamine-N-oxide dihydrate, (TMAO) as kosmotropic agent and anhydrous sodium sulfate as anti-chaotrope salt.

Comparative corrosion study of Ti-Ta alloys for dental applications.

Besides other important material features, the corrosion parameters and corrosion products are responsible for limiting the biocompatibility of metallic materials, and can produce undesirable reactions in implant-adjacent and/or more distant tissues. Titanium and some of its alloys are known as being the most biocompatible metallic materials due to their high strength, low modulus, high corrosion resistance in biological media, etc. More recently, Ti-Ta alloys have been developed, and these are expected to become more promising candidates for biomedical and dental applications than commercially pure Ti, Ti-6Al-4V or Ti-6Al-7Nb alloy.

A computerized data analysis method for electrogastrographic signals.

Unlabelled: Many recent studies showed that EGG signal can be used to diagnose and monitor patients with gastric motility disorders.

Material And Method: This paper presents the way to record and process the EGG signal, and the results of study on a sample of 10 patients. These patients are initially evaluated by upper endoscopy were are normal without gastric motility dysfunction or some gastric lesions.

Cadmium tolerance and adsorption by the marine brown alga Fucus vesiculosus from the Irish Sea and the Bothnian Sea.

Cadmium (Cd) uptake capacities and Cd tolerance of the marine alga Fucus vesiculosus from the Irish Sea (salinity 35 psu) and from the Bothnian Sea (northern Baltic, 5 psu) were quantified. These data were complemented by measurements of changes in maximal photosynthetic rate (P(max)), dark respiration rate and variable fluorescence vs. maximal fluorescence (F(v):F(m)).

SEM and EDX studies of bioactive hydroxyapatite coatings on titanium implants.

This work presents a study on an alternative coating method based on biomimetic techniques which are designed to form a crystalline hydroxyapatite layer very similar to the process corresponding to the formation of natural bone. The HA formation on the surface of titanium alloy pretreated with NaOH solution is investigated. Two types of solutions such as supersaturated calcification solution (SCS) and modified SCS (M-SCS) were used to investigate bone-like apatite formation on alkali-treated titanium.

Thermal power plants ash as sorbent for the removal of Cu(II) and Zn(II) ions from wastewaters.

This study concerns the sorption of copper(II) and zinc(II) ions on an energy pit coal fly ash, a massive by-product of a thermal power station in Iaşi, Romania. In order to establish the optimum conditions of Cu(II) and Zn(II) sorption on the fly ash, the influence of experimental conditions (solution pH, adsorbent dose and metal ion concentration, temperature and contact time) was studied. The equilibrium data at three different temperatures were processed using the Langmuir isotherm model.

Immobilization of alpha-[di-(beta-chloroethyl)-amide]-N-(m-nitrobenzoyl)-D,L-asparagic acid on xanthan.

The paper studies the coupling reaction, through ester-type covalent bonds, of an oxazolone derived from the N-(m-nitrobenzoyl)-L-asparagic acid, the cycle of which is opened with an N-mustard derivative, on xanthan (a polysaccharide of microbian synthesis), in conditions of activation with dicyclohexyl carbodiimide. The coupling product has been characterized through elemental analysis and IR spectroscopy. For the establishment of the capacity of the active principle's controlled release by the polymer-active principle system thus obtained, active principle's release kinetics from the polysaccharide support, in conditions of basic hydrolysis, is studied.