Coupling Charge and Topological Reconstructions at Polar Oxide Interfaces.

In oxide heterostructures, different materials are integrated into a single artificial crystal, resulting in a breaking of inversion symmetry across the heterointerfaces. A notable example is the interface between polar and nonpolar materials, where valence discontinuities lead to otherwise inaccessible charge and spin states. This approach paved the way for the discovery of numerous unconventional properties absent in the bulk constituents. However, control of the geometric structure of the electronic wave functions in correlated oxides remains an open challenge. Here, we create heterostructures consisting of ultrathin SrRuO_{3}, an itinerant ferromagnet hosting momentum-space sources of Berry curvature, and LaAlO_{3}, a polar wide-band-gap insulator. Transmission electron microscopy reveals an atomically sharp LaO/RuO_{2}/SrO interface configuration, leading to excess charge being pinned near the LaAlO_{3}/SrRuO_{3} interface. We demonstrate through magneto-optical characterization, theoretical calculations and transport measurements that the real-space charge reconstruction drives a reorganization of the topological charges in the band structure, thereby modifying the momentum-space Berry curvature in SrRuO_{3}. Our results illustrate how the topological and magnetic features of oxides can be manipulated by engineering charge discontinuities at oxide interfaces.

Coherent spin-wave transport in an antiferromagnet.

Magnonics is a research field complementary to spintronics, in which quanta of spin waves (magnons) replace electrons as information carriers, promising lower dissipation1-3. The development of ultrafast nanoscale magnonic logic circuits calls for new tools and materials to generate coherent spin waves with frequencies as high, and wavelengths as short, as possible4,5. Antiferromagnets can host spin waves at terahertz (THz) frequencies and are therefore seen as a future platform for the fastest and the least dissipative transfer of information6-11. However, the generation of short-wavelength coherent propagating magnons in antiferromagnets has so far remained elusive. Here we report the efficient emission and detection of a nanometer-scale wavepacket of coherent propagating magnons in antiferromagnetic DyFeO3 using ultrashort pulses of light. The subwavelength confinement of the laser field due to large absorption creates a strongly non-uniform spin excitation profile, enabling the propagation of a broadband continuum of coherent THz spin waves. The wavepacket contains magnons with a shortest detected wavelength of 125 nm that propagate with supersonic velocities of more than 13 km/s into the material. This source of coherent short-wavelength spin carriers opens up new prospects for THz antiferromagnetic magnonics and coherence-mediated logic devices at THz frequencies.

Ultrafast control of magnetic interactions via light-driven phonons.

Resonant ultrafast excitation of infrared-active phonons is a powerful technique with which to control the electronic properties of materials that leads to remarkable phenomena such as the light-induced enhancement of superconductivity1,2, switching of ferroelectric polarization3,4 and ultrafast insulator-to-metal transitions5. Here, we show that light-driven phonons can be utilized to coherently manipulate macroscopic magnetic states. Intense mid-infrared electric field pulses tuned to resonance with a phonon mode of the archetypical antiferromagnet DyFeO3 induce ultrafast and long-living changes of the fundamental exchange interaction between rare-earth orbitals and transition metal spins. Non-thermal lattice control of the magnetic exchange, which defines the stability of the macroscopic magnetic state, allows us to perform picosecond coherent switching between competing antiferromagnetic and weakly ferromagnetic spin orders. Our discovery emphasizes the potential of resonant phonon excitation for the manipulation of ferroic order on ultrafast timescales6.

What do professionals recommend regarding the frequency of self-monitoring of blood glucose?

BACKGROUND: Patients' adherence to guidelines regarding self-monitoring of blood glucose (SMBG) is limited. However, there are no previous reports about the recommendations that are given in clinical practice concerning SMBG. The aim of this study was to investigate what healthcare providers recommend to insulin-treated patients with diabetes regarding frequency and timing of SMBG. METHODS: In this cross-sectional descriptive study, primary care assistants, diabetes specialised nurses and doctors in the Netherlands were invited via e-mail to complete an internet survey. RESULTS: A total of 980 (14%) professionals returned the questionnaire. Insulin pump users and patients with type 1 diabetes (T1DM) on 4 injections a day were advised to perform SMBG daily by 96% and 63% of the professionals, respectively. The majority of the professionals advised these patients to perform 3-4 measurements per day. There was less agreement on the timing (pre- and÷or postprandial). Patients with type 2 diabetes (T2DM) on four injections were advised to perform SMBG less frequently. There was a wide variation in recommendations that were given to patients with T2DM on less intensive insulin regimens. CONCLUSION: This study investigated SMBG from a professional's perspective. A considerable and relevant variation in the recommendations about the number and timing of SMBG was observed. The most striking differences were found in patients with T2DM on less intensive insulin regimes, also with respect to the frequency of SMBG. Well-designed studies are necessary in order to give a more evidence-based advice on the basic frequency and timing of SMBG.

Needlestick injuries and infectious patients in a major academic medical centre from 2003 to 2010.

To implement adequate preventive measures in a hospital, the number and nature of occupational exposures to blood must be known. In the Amsterdam Academic Medical Centre a standardised procedure was used to assess all reported occupational exposures to blood from 2003 to 2010. 1601 incidents were reported of which 66% were needlestick accidents. Thirty-five percent of the incidents concerned persons in training and 27% concerned experienced nurses. Twenty-nine percent of accidents occurred during cleaning up after a medical procedure, including the recapping of needles in 6%. In 8% of the accidents the patient was known or found to be infected with hepatitis B or C virus or HIV and in 86% of accidents the personnel were immune to HBV. One case of HCV transmission occurred. The number and nature of the occupational exposures indicate that preventive measures must focus on the replacement of needles by safety devices and on awareness training of experienced nurses and of persons in training.

Self-monitoring of blood glucose in tablet-treated type 2 diabetic patients (ZODIAC).

BACKGROUND: Whether self-monitoring of blood glucose (SMBG) improves glycaemic control in patients with type 2 diabetes mellitus (T2DM) not using insulin is questionable. Our aim was to investigate the effects of SMBG in patients with T2DM who were in persistent moderate glycaemic control whilst not using insulin. METHODS: Patients were eligible when between 18 and 70 years of age, with an HbA1c between 7 and 8.5%, using one or two oral blood glucose lowering agents. Forty-one of the anticipated 52 patients were randomly assigned to receive either SMBG added to usual care, or to continue with usual care for one year. A fasting glucose value and three postprandial glucose values were measured twice weekly (including a Saturday or a Sunday). The primary efficacy parameter was HbA1c. Furthermore, health-related quality of life and treatment satisfaction were assessed using the Short-form 36 Health Survey Questionnaire (SF-36), the Type 2 Diabetes Symptom Checklist (DSC-r), the Diabetes Treatment Satisfaction Questionnaire (DTSQ) and the WHO -Wellbeing Index (WHO-5). RESULTS: Change in HbA1c between groups was -0.05% (95% CI: -0.51, 0.41; p=0.507). Also, there were no significant changes between groups on the DTSQ , DSC type 2, WHO-5 or SF -36, except for the SF -36 dimension 'health change' which was lower in the SBMG group (mean difference: -12 (95% CI: -20.9, -3.1). CONCLUSION: On top of the absence of a clinical benefit, tablet-treated T2DM patients experienced some worsening of their health perception. We therefore argue that the use of SMBG in this patient group is questionable, and its unlimited use and promotion should be reconsidered.