Electric Pulse Induced Resistive Switching, Electronic Phase Separation, and Possible Superconductivity in a Mott insulator

Metal-insulator transitions (MIT) belong to a class of fascinating physical phenomena, which includes superconductivity, and colossal magnetoresistance (CMR), that are associated with drastic modifications of electrical resistance. In transition metal compounds, MIT are often related to the presence of strong electronic correlations that drive the system into a Mott insulator state. In these systems the MIT is usually tuned by electron doping or by applying an external pressure. However, it was noted recently that a Mott insulator should also be sensitive to other external perturbations such as an electric field. We report here the first experimental evidence of a non-volatile electric-pulse-induced insulator-to-metal transition and possible superconductivity in the Mott insulator GaTa4Se8. Our Scanning Tunneling Microscopy experiments show that this unconventional response of the system to short electric pulses arises from a nanometer scale Electronic Phase Separation (EPS) generated in the bulk material.Comment: Highlight in Advanced Functional Materials 18, 1-4 (2008) doi : 10.1002/adfm.20080055

A doubly responsive probe for the detection of Cys4-tagged proteins

International audienceRecombinant proteins bearing a tag are crucial tools for assessing protein location or function. Small tags such as Cys4 tag (tetracysteine; Cys–Cys–X–X–Cys–Cys) are less likely disrupt protein function in the living cell than green fluorescent protein. Herein we report the first example of the design and synthesis of a dual fluorescence and hyperpolarized 129Xe NMR-based sensor of Cys4-tagged proteins. This sensor becomes fluorescent when bound to such Cys4-tagged peptides, and the 129Xe NMR spectrum exhibits a specific signal, characteristic of the biosensor-peptide association

Cognitive loading affects motor awareness and movement kinematics but not locomotor trajectories during goal-directed walking in a virtual reality environment.

The primary purpose of this study was to investigate the effects of cognitive loading on movement kinematics and trajectory formation during goal-directed walking in a virtual reality (VR) environment. The secondary objective was to measure how participants corrected their trajectories for perturbed feedback and how participants' awareness of such perturbations changed under cognitive loading. We asked 14 healthy young adults to walk towards four different target locations in a VR environment while their movements were tracked and played back in real-time on a large projection screen. In 75% of all trials we introduced angular deviations of ±5° to ±30° between the veridical walking trajectory and the visual feedback. Participants performed a second experimental block under cognitive load (serial-7 subtraction, counter-balanced across participants). We measured walking kinematics (joint-angles, velocity profiles) and motor performance (end-point-compensation, trajectory-deviations). Motor awareness was determined by asking participants to rate the veracity of the feedback after every trial. In-line with previous findings in natural settings, participants displayed stereotypical walking trajectories in a VR environment. Our results extend these findings as they demonstrate that taxing cognitive resources did not affect trajectory formation and deviations although it interfered with the participants' movement kinematics, in particular walking velocity. Additionally, we report that motor awareness was selectively impaired by the secondary task in trials with high perceptual uncertainty. Compared with data on eye and arm movements our findings lend support to the hypothesis that the central nervous system (CNS) uses common mechanisms to govern goal-directed movements, including locomotion. We discuss our results with respect to the use of VR methods in gait control and rehabilitation

Pneumococcal polyarticular septic arthritis after a single infusion of infliximab in a rheumatoid arthritis patient: a case report

<p>Abstract</p> <p>Introduction</p> <p>We present a case of <it>Streptococcus pneumoniae </it>polyarticular septic arthritis in a patient with rheumatoid arthritis receiving a single infusion of infliximab.</p> <p>Case presentation</p> <p>A 38-year-old Japanese man with a 5-year history of seronegative rheumatoid arthritis had previously received sulphasalazine and methotrexate therapies and was on regular low-dose prednisolone therapy. Despite these treatments, his disease activity remained high and infliximab was introduced in addition to methotrexate, prednisolone, and folic acid. However, he was admitted to hospital with a fever of 40.6°C, chills, and polyarthralgia eight days after the first infusion of infliximab. His joints were swollen, painful, and warm. Laboratory data showed marked acute inflammation. He was diagnosed with bacterial septic polyarthritis, and emergency surgical joint lavage and drainage was performed at the knees along with needle aspiration and lavage of the ankles and right wrist. He was then given intravenous antibiotic therapy for 31 days. He made a good recovery and was discharged on day 37.</p> <p>Conclusions</p> <p>We believe this is the first reported case of severe pneumococcal septic arthritis requiring hospitalization in a patient treated with infliximab. <it>S. pneumonia </it>is now a well-recognized but uncommon cause of polyarticular septic arthritis that can lead to cessation of therapy, as in our patient's case.</p

Access to treatment in prison: an inventory of medication preparation and distribution approaches

The preparation and distribution of medication in prisons or jails are critical for individuals to access their treatment. This process is resource-intensive for healthcare professionals and may violate principles of confidentiality, autonomy, respect, and dignity if non-qualified staff are involved. However, there are no published best practices on the topic. This report aims to bridge this gap by presenting the results of a mapping exercise on different models of medication preparation and delivery. Authors call upon healthcare professionals to enrich this live document to inform health services research further and improve access to prescribed medications for people experiencing incarceration.</ns4:p