Two-dimensional superconductivity at the (111)LaAlO3_3/SrTiO3_3 interface

We report on the discovery and transport study of the superconducting ground state present at the (111)LaAlO$_3$/SrTiO$_3$ interface. The superconducting transition is consistent with a Berezinskii-Kosterlitz-Thouless transition and its 2D nature is further corroborated by the anisotropy of the critical magnetic field, as calculated by Tinkham. The estimated superconducting layer thickness and coherence length are 10 nm and 60 nm, respectively. The results of this work provide a new platform to clarify the microscopic details of superconductivity at LaAlO$_3$/SrTiO$_3$ interfaces, in particular in what concerns the link with orbital symmetry.Comment: 4 pages, 4 figure

Probing dynamics of an electron-spin ensemble via a superconducting resonator

We study spin relaxation and diffusion in an electron-spin ensemble of nitrogen impurities in diamond at low temperature (0.25-1.2 K) and polarizing magnetic field (80-300 mT). Measurements exploit mode- and temperature-dependent coupling of hyperfine-split sub-ensembles to the resonator. Temperature-independent spin linewidth and relaxation time suggest that spin diffusion limits spin relaxation. Depolarization of one sub-ensemble by resonant pumping of another indicates fast cross-relaxation compared to spin diffusion, with implications on use of sub-ensembles as independent quantum memories.Comment: 5 pages, 5 figures, and Supplementary Information (2 figures

Viewpoint: filovirus haemorrhagic fever outbreaks: much ado about nothing?

The recent outbreak of Marburg haemorrhagic fever in the Democratic Republic of Congo has put the filovirus threat back on the international health agenda. This paper gives an overview of Marburg and Ebola outbreaks so far observed and puts them in a public health perspective. Damage on the local level has been devastating at times, but was marginal on the international level despite the considerable media attention these outbreaks received. The potential hazard of outbreaks, however, after export of filovirus from its natural environment into metropolitan areas, is argued to be considerable. Some avenues for future research and intervention are explored. Beyond the obvious need to find the reservoir and study the natural history, public health strategies for a more timely and efficient response are urgently needed

The application of fluorescence techniques in meningioma surgery-a review

Surgical resections of meningiomas, the most common intracranial tumor in adults, can only be curative if radical resection is achieved. Potentially, the extent of resection could be improved, especially in complex and/or high-grade meningiomas by fluorescence-guided surgery using 5-aminolevulinic acid (5-ALA), indocyanine green (ICG), or fluorescein. This review aims to summarize and evaluate these fluorescence-guided meningioma surgery techniques. PubMed and Embase were searched for relevant articles. Additionally, we checked reference lists for further studies. Forty-eight articles were included in the final analysis. 5-ALA fluoresced with varying sensitivity and selectivity in meningiomas and in invaded bone and dura mater. Although ICG was mainly applied for video angiography, one report shows tumor fluorescence 18-28 h post-ICG injection. Lastly, the use of fluorescein could aid in the identification of tumor remnants; however, detection of dural tail is highly questionable. Fluorescence-guided meningioma surgery should be a reliable, highly specific, and sensitive technique. Despite numerous studies reporting the use of fluorescent dyes, currently, there is no evidence that these tools improve the radical resection rate and long-term recurrence-free outcome in meningioma surgery without neurological deficits. Evidence regarding the effectiveness and increased safety of resection after the application of these fluorophores is currently lacking. Future research should focus on the development of a meningioma-targeted, highly sensitive, and specific fluorophore

Pure cervical radiculopathy due to spontaneous spinal epidural haematoma (SSEH): report of a case solved conservatively

Introduction: Spontaneous spinal epidural haematoma (SSEH) is widely recognised throughout the literature as a cause of myelopathy, radicular compression being very rarely reported. Surgical management is almost always recommended, especially in the cases of spinal cord compression. Conservative treatment is reported as a curiosity and only in the case of spontaneous improvement. This report presents the particular case of a 64-year-old patient undergoing anticoagulant therapy that had a cervical radiculopathy due to a SSEH confirmed by MRI. The patient improved spontaneously and symptoms were solved with unconventional conservative treatment and without stopping the anticoagulant therapy. Conclusions: Spontaneous epidural haematoma must be kept in mind when patients undergoing anticoagulant therapy have a sudden onset of cervicobrachialgia. Even though most spinal surgeons advocate surgical treatment, a conservative approach may lead to a complete recovery and may be considered as a good option in the case of radicular involvement. Discontinuation of the anticoagulant therapy may not always be needed, especially when the clinical syndrome improves spontaneously

Insights from the supplementary motor area syndrome in balancing movement initiation and inhibition

The supplementary motor area syndrome is a characteristic neurosurgical syndrome that can occur after unilateral resection of the supplementary motor area. Clinical symptoms may vary from none to a global akinesia, predominantly on the contralateral side, with preserved muscle strength, and mutism. A remarkable feature is that these symptoms completely resolve within weeks to months, leaving only a disturbance in alternating bimanual movements. In this review we give an overview of the old and new insights from the supplementary motor area syndrome and extrapolate these findings to seemingly unrelated diseases and symptoms such as Parkinson’s disease and tics. Furthermore, we integrate findings from lesion, stimulation and functional imaging studies to provide insight in the motor function of the supplementary motor area

Vasopressin release is enhanced by the Hemocontrol biofeedback system and could contribute to better haemodynamic stability during haemodialysis

Haemodialysis with the Hemocontrol biofeedback system (HHD) is associated with improved haemodynamic stability compared with standard haemodialysis (HD) (SHD). Although the beneficial effect of HHD on haemodynamic stability is generally explained by its effect on blood volume, we questioned whether additional factors could play a role. Since HHD is associated with higher initial dialysate sodium concentrations and ultrafiltration (UF) rate, we studied whether the beneficial effect of HHD on haemodynamic stability may be explained by an increased release of the vasoconstrictor arginine vasopressin (AVP). Fifteen chronic dialysis patients underwent SHD and HHD in random order. All other treatment factors were identical and patients served as their own control. Plasma levels of AVP were measured pre-dialysis, at 30 and 60 min intra-dialysis and, next, hourly until completion of the dialysis session. Plasma AVP levels did not change significantly during SHD, whereas AVP levels rose significantly within 30 min after the start of HHD (P 0.01). AVP levels were significantly higher at 30 and 60 min of HHD in comparison with SHD (P 0.05). Dialysis hypotension occurred significantly less frequent during HHD than during SHD (P 0.05). HHD is associated with higher initial AVP levels compared with SHD. The enhanced release of the vasoconstrictor AVP with HHD could contribute to the lower frequency of dialysis hypotension by facilitating fluid removal during the first part of the dialysis session, permitting lower UF rates during the second half of the dialysis session

Isotope effects in underdoped cuprate superconductors: a quantum phenomenon

We show that the unusual doping dependence of the isotope effects on transition temperature and zero temperature in - plane penetration depth naturally follows from the doping driven 3D-2D crossover, the 2D quantum superconductor to insulator transition (QSI) in the underdoped limit and the change of the relative doping concentration upon isotope substitution. Close to the QSI transition both, the isotope coefficient of transition temperature and penetration depth approach the coefficient of the relative dopant concentration, and its divergence sets the scale. These predictions are fully consistent with the experimental data and imply that close to the underdoped limit the unusual isotope effect on transition temperature and penetration depth uncovers critical phenomena associated with the quantum superconductor to insulator transition in two dimensions.Comment: 6 pages, 3 figure