Improvement of Processing of Gold-Bearing Sulfide Minerals by Treatment by Magnetic Colloids

Journal of Mining Science - The experimental data on modification of magnetic properties of gold-bearing sulfide ore using magnetic colloids are reported. The magnetic product of the high-gradient...     

Evidence of basolateral water permeability regulation in amphibian urinary bladder

It is well known that arginine vasopressin (AVP) produces up to a 40-fold increase (0.1 to 4.0 microL/min.cm2) in net water flux across the amphibian urinary bladder under an osmotic gradient (mucosal side 10% hypotonic). No AVP effect is observed when the gradient is in the opposite direction (serosal hypotonic). Similar asymmetrical behavior to osmotic gradients occurs in the frog corneal epithelium. This rectification phenomenon has not been satisfactorily explained. We measured net water fluxes in bladder sacs and confirmed that AVP has no effect when the serosal bath is hypotonic. We reasoned that the 'abnormal' serosal osmolarity was inducing changes in membrane water permeability, the very parameter being measured. Thus, we studied the effect of solution osmolarity on diffusional water flow (Jdw) across the frog bladder using 3H2O. As expected, AVP doubled Jdw (in either direction from 12 to 21 microL/min.cm2) when the serosal solution was iso-osmolar regardless of mucosal osmolarity. However, in the AVP-stimulated bladders, hypo-osmolarity of the serosal solution reduced Jdw by 42%, an effect that was reversible when normal osmolarity was re-established. Amphotericin B (instead of AVP) was used to irreversibly increase the permeability to water of the apical membrane. Under these conditions, basolateral hypotonicity also reversibly decreased Jdw by 32%, suggesting the basolateral membrane as the site where permeability is reduced. SEM and TEM of the tissue shows extreme swelling when it was exposed to serosal hypotonicity with or without AVP and typical surface morphology changes following hormone stimulation. We conclude that this swelling may initiate a signaling mechanism that reduces basolateral water permeability. These findings constitute evidence of basolateral water channel permeability regulation, which can also contribute to cell volume regulation.     

“The grass is greener on the other side”: The relationship between the Brexit referendum results and spatial inequalities at the local level

Despite seven decades of development of the European Union project, on 23 June 2016, the United Kingdom, Europe and the rest of the world were surprised when the Leave campaign won the Brexit referendum, offering an extraordinary case study for researchers. We spatially disaggregate the vote share data, which allows us to explore where anti-European sentiment took root in the UK and why. In this paper, a spatial dependence model is applied to clarify and quantify the relevance of the different dimensions—demographic, cultural/educational and economic—that play a role in explaining the rise of support for the Leave campaign. The analysis is conducted at the local level, using local authorities (LAs) as the spatial unit of analysis due to the combination of official datasets with newly generated data in the context of an EU H2020 project. A new indicator capturing the affluence of each local area relative to its close neighbours is proposed and included in the model. In general, we observe that most of the main conclusions obtained by large regions or at the national level also hold at the local scale. However, it is particularly interesting that inequalities by LAs are clearly significant, indicating a marked influence on voters' decisions that have thus far been unaccounted for. This result provides further support for the existence of, to use Andrés Rodriguez-Pose's terminology, an even more intense “revenge of the places that do not matter” at the local scale.     

A robust,four-node,quadrilateral element for stress analysis of functionally graded plates through higher-order theories

ABSTRACT

A hybrid-mixed, four-node, quadrilateral element for the three-dimensional (3D) stress analysis of functionally graded (FG) plates using the method of sampling surfaces (SaS) is developed. The SaS formulation is based on choosing an inside the plate body N, not equally spaced SaS parallel to the middle surface, in order to introduce the displacements of these surfaces as basic plate variables. Such a choice of unknowns, with the consequent use of Lagrange polynomials of the degree N ? 1 in the assumed distributions of displacements, strains, and mechanical properties through the thickness leads to a robust FG plate formulation. All SaS are located at Chebyshev polynomial nodes that permit one to minimize uniformly the error due to the Lagrange interpolation. To avoid shear locking and spurious zero-energy modes, the assumed natural strain method is employed. The proposed four-node quadrilateral element passes 3D patch tests for FG plates and exhibits a superior performance in the case of coarse distorted meshes. It can be useful for the 3D stress analysis of thin and thick metal/ceramic plates because the SaS formulation gives an opportunity to obtain the solutions with a prescribed accuracy, which asymptotically approach the 3D exact solutions of elasticity as the number of SaS tends to infinity.     

Anisotropic magneto-resistive transducer-gradiometer of magnetic field

New type of anisotropic magneto-resistive transducer of magnetic field representing magnetic field gradiometer with even volt-oersted characteristic saturated with magnetic field increase, is considered. Results of its development are given as magneto-sensitive nanoelement for biosensor and magnetic head.