Super-hard Superconductivity

We present a study of the magnetic response of Type-II superconductivity in the extreme pinning limit, where screening currents within an order of magnitude of the Ginzburg-Landau depairing critical current density develop upon the application of a magnetic field. We show that this "super-hard" limit is well approximated in highly disordered, cold drawn, Nb and V wires whose magnetization response is characterized by a cascade of Meissner-like phases, each terminated by a catastrophic collapse of the magnetization. Direct magneto-optic measurements of the flux penetration depth in the virgin magnetization branch are in excellent agreement with the exponential model in which J_c(B)=J_co exp(-B/B_o), where J_co~5x10^6 A/cm^2 for Nb. The implications for the fundamental limiting hardness of a superconductor are discussed.Comment: corrected Fig.

Oriented hydroxyapatite single crystals produced by the electrodeposition method

International audienceWe propose here the use of cathodic electrodeposition as tool to fabricate implant coatings consisting in nano/micro single crystals of hydroxyapatite (HA), preferentially orientated along the c-axis. Coating characterization is the base of this work, where we discuss the mechanisms related to the deposition of oriented hydroxyapatite thin films. It is shown that when deposited on titanium alloys, the HA coating is constituted by two distinct regions with different morphologies: at a distance of few microns from the substrate, large HA single crystals are oriented along the c-axis and appear to grow up from a base material, consisting in an amorphous HA. This organized system has a great importance for cell investigation once the variables involved in the cell/surface interaction are reduced. The use of such systems could give a new insight on the effect of particular HA orientation on the osteoblast cells

RESCUE‐ICAS: Rationale and Study Design

BACKGROUND Mechanical thrombectomy (MT) failure occurs in ≈10% to 20% of MTs. Among the common causes of failed MT is residual underlying intracranial stenosis (ICAS), typically attributable to atherosclerotic disease. ICAS large‐vessel occlusion (ICAS‐LVO) remains poorly understood, and management of ICAS‐LVO is unclear. The RESCUE‐ICAS (Registry of Emergent Large Vessel Occlusion Due to Intracranial Stenosis) aims at providing better understanding of the prevalence of ICAS‐LVO, and the overall safety and efficacy of various rescue therapies. METHODS RESCUE‐ICAS is a multicenter, international, prospective registry that is currently enrolling patients with ICAS‐LVO who underwent MT. All sites are required to report monthly MT cases that meet inclusion criteria. The decision of whether to use rescue therapy is up to the interventionist. RESULTS We will collect patients’ demographic, clinical, and radiographic data at baseline. Also, we will capture variables related to the MT procedure and rescue therapy (if performed), and postprocedural clinical and imaging variables. Outcomes include the rate of successful recanalization, defined by modified Thrombolysis in Cerebral Infarction score of ≥2b, the rate of symptomatic intracranial hemorrhage, the 90‐day modified Rankin scale score, and mortality. CONCLUSIONS No strong evidence is currently available to support an optimal treatment strategy for patients with ICAS‐LVO undergoing MT. RESCUE‐ICAS is a prospective cohort study that will provide important data to help design randomized controlled trials