Reversibility in the Physical Properties of Agarose Gels following an Exchange in Solvent and Non-Solvent.

Agarose forms a homogeneous thermoreversible gel in an aqueous solvent above a critical polymer concentration. Contrary to the prevailing consensus, recent confirmations indicate that agarose gels are also stable in non-solvents like acetone and ethanol. A previous study compared gel characterisations and behaviours in water and ethanol, discussing the gelation mechanism.

Comprehensive experimental dataset on large-amplitude Rayleigh-Plateau instability in continuous InkJet printing regime.

The Rayleigh-Plateau instability, a phenomenon of paramount significance in fluid dynamics, finds widespread application in the Continuous InkJet (CIJ) printing process. This study presents a comprehensive dataset comprising experimental investigations of fluid jet breakup phenomena under large-amplitude stimulation conditions using an industrial CIJ print-head from Markem-Imaje. Unlike previous studies, this dataset encompasses a diverse range of experimental conditions, including nine different Newtonian fluids with meticulously measured rheological properties (viscosities, surface tensions and densities).

Characterization of Agarose Gels in Solvent and Non-Solvent Media.

Agarose is known to form a homogeneous thermoreversible gel in an aqueous medium over a critical polymer concentration. The solid-liquid phase transitions are thermoreversible but depend on the molecular structure of the agarose sample tested. The literature has mentioned that agarose gels could remain stable in non-solvents such as acetone or ethanol.

Rheological Behavior of Pectin Gels Obtained from Araçá ( Sabine) Fruits: Influence of DM, Pectin and Calcium Concentrations.

In this work, purified pectins from Araçá fruits ( Sabine) were obtained and characterized after partial demethylation. On each prepared sample, the carboxylic yield was obtained by titration, the degree of methylation (DM) by H-NMR, and the molecular weight distribution by steric exclusion chromatography (SEC). Then, the gelation ability in the presence of calcium counterions was investigated and related to DM (59-0%); the pectin concentration (2-10 g L); and the CaCl concentration (0.

Dataset of numerically-generated interfaces of Newtonian jets in CIJ regime.

The so-called Rayleigh-Plateau instability of fluid jets has been widely studied and is extensively used in the Continuous InkJet (CIJ) printing process. The present dataset contains the numerically-generated interfaces of Newtonian fluids jets in CIJ jetting conditions for low to moderately high stimulation amplitudes. We used Basilisk, an open-source Computational Fluid Dynamics (CFD) software specialized in multiphase flow to compute thousands of jets of fluids for Reynolds numbers ranging from 100 to 1000.

Structural characterization of the interfacial self-assembly of chitosan with oppositely charged surfactant.

Controlling the assembly of polyelectrolytes and surfactant at liquid-liquid interfaces offers new ways to fabricate soft materials with specific physical properties. However, little is known of the relationships between the kinetics of interfacial assembly, structural and rheological properties of such interfaces. We studied the kinetics at water-oil interface of the assembly of a positively charged biopolymer, chitosan, with an anionic fatty acid using a multi-scale approach.

Undernutrition combined with dietary mineral oil hastens depuration of stored dioxin and polychlorinated biphenyls in ewes. 2. Tissue distribution, mass balance and body burden.

Food safety crises involving persistent organic pollutants (POPs) lead to systematic slaughter of livestock to prevent contaminants from entering the food chain. Therefore, there is a need to develop strategies to depurate livestock moderately contaminated with POPs to reduce economic and social damage. This study aimed to test undernutrition (37% of energy requirements) combined with mineral oil (10% in total dry matter intake) in nine non-lactating ewes contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) 126 and 153 as a strategy to enhance the depuration of POPs through faecal excretion.

Hydroxyl Functionalized Pyridinium Ionic Liquids: Experimental and Theoretical Study on Physicochemical and Electrochemical Properties.

Structurally modified hydroxyl functionalized pyridinium ionic liquids (ILs), liquid at room temperature, were synthesized and characterized. Alkylated -(2-hydroxyethyl)-pyridinium ILs were prepared from alkylpyridines via corresponding bromide salts by -alkylation (65-93%) and final anion exchange (75-96%). Pyridinium-alkylation strongly influenced the IL physicochemical and electrochemical properties.

Role of Electrostatic Interactions on Supramolecular Organization in Calf-Thymus DNA Solutions under Flow.

Previous investigations were conducted on two concentrations of DNA solution: 4 mg/mL, for which it has been shown that no supramolecular organization is induced under flow at low shear rates; and 10 mg/mL, in which a liquid crystalline-type texture is formed under flow at low shear rates, attesting to an orientation of pre-organized chains. Rheological experiments are discussed and their results supported by small-angle X-ray scattering (SAXS) and flow birefringence visualization experiments. Scattering from polyelectrolytes has a characteristic signal, which is here observed in SAXS, showing a strong correlation peak between charged chains in water, for both concentrations.

Redox-Triggered Folding of Self-Assembled Coordination Polymers incorporating Viologen Units.

We report the study of stimuli-responsive Zn and Fe coordination polymers (MC3 or MC2 with M=Fe or Zn ). These soluble metallopolymers were formed spontaneously by reaction of an organic ligand (C3 or C2 ) with one molar equivalent of metal ions. The C3 and C2 ligands incorporate two chelating terpyridine groups bridged by a redox responsive hinge featuring two viologen units (viologen=N,N'-dialkyl-4,4'-bipyridinium) linked either with propyl (C3 ) or ethyl (C2 ) chains.

Effects of synthetic biomacromolecule addition on the flow behavior of concentrated mesenchymal cell suspensions.

In the fields of tissue engineering and regenerative medicine, many researchers and companies alike are investigating the utility of concentrated mesenchymal stem cell suspensions as therapeutic injectables, with the hope of regenerating the damaged tissue site. These cells are seldom used alone, being instead combined with synthetic biomacromolecules, such as branched poly(ethylene glycol) (PEG) polymers, in order to form cross-linked hydrogels postinjection. In this article, we present the results of a detailed experimental and analytical investigation into the impacts of a range of eight-arm PEG polymers, each presenting functional end groups, on the rheological properties of concentrated living cells of mesenchymal origin.

Effects of cell density and biomacromolecule addition on the flow behavior of concentrated mesenchymal cell suspensions.

With the rapidly growing interest in the use of mesenchymal stromal cells (MSCs) for cell therapy and regenerative medicine applications, either alone as an injected suspension, or dispersed within injectable hydrogel delivery systems, greater understanding of the structure-function-property characteristics of suspensions of adhesion-dependent mesenchymal cells is required. In this paper, we present the results of an experimental study into the flow behavior of concentrated suspensions of living cells of mesenchymal origin (fibroblasts) over a wide range of cell concentrations, with and without the addition of hyaluronic acid (HA), a commonly utilized biomolecule in injectable hydrogel formulations. We characterize the change in the shear viscosity as a function of shear stress and shear rate for cell volume fractions varying from 20 to 60%.

Prenatal diagnosis and management of sex chromosome aneuploidy: a report on 98 cases.

Objectives: To analyse the management of pregnancy after prenatal diagnosis of sex chromosome aneuploidy (SCA) and the factors influencing genetic counselling and parental decision.

Methods: Between 1991 and 2001, 73 non-mosaic fetal SCA were diagnosed in our centre and 25 were referred to us from outside institutions. The same geneticist carried out genetic counselling.

Feasibility, accuracy and safety of chorionic villus sampling: a report of 10741 cases.

Objectives: To evaluate the feasibility, accuracy and safety of chorionic villus sampling (CVS).

Methods: Ten thousand seven hundred and forty one singleton pregnancies at risk of chromosome abnormalities (96.3%) and gene disorders (2.