Engaging indigenous patient partners in patient-oriented research: lessons from a one-year initiative.

Background: Patient-oriented research (POR) is a specific application of participatory research that promotes active patient engagement in health research. There is a growing concern that people involved in POR do not reflect the diversity of the population such research aims to serve, but are rather those more 'easily' engaged with institutions, organizations and society. Indigenous peoples are among such groups generally underrepresented in POR.

Drug samples in family medicine teaching units: a cross-sectional descriptive study: Part 1: drug sample management policies and the relationship between the pharmaceutical industry and residents in Quebec.

Objective: To determine the existence and the level of health care professional (HCP) knowledge of local policies regarding drug sample use and the relationship between residents and the pharmaceutical industry in academic primary health care settings.

Design: Descriptive cross-sectional survey. Health care providers were invited to complete a self-administered questionnaire on drug sample use between February and December 2013.

Ultrafast evolution and transient phases of a prototype out-of-equilibrium Mott-Hubbard material.

The study of photoexcited strongly correlated materials is attracting growing interest since their rich phase diagram often translates into an equally rich out-of-equilibrium behaviour. With femtosecond optical pulses, electronic and lattice degrees of freedom can be transiently decoupled, giving the opportunity of stabilizing new states inaccessible by quasi-adiabatic pathways. Here we show that the prototype Mott-Hubbard material VO presents a transient non-thermal phase developing immediately after ultrafast photoexcitation and lasting few picoseconds.

Laser-Induced Charge-Density-Wave Transient Depinning in Chromium.

We report on time-resolved x-ray diffraction measurements following femtosecond laser excitation in pure bulk chromium. Comparing the evolution of incommensurate charge-density-wave (CDW) and atomic lattice reflections, we show that, a few nanoseconds after laser excitation, the CDW undergoes different structural changes than the atomic lattice. We give evidence for a transient CDW shear strain that breaks the lattice point symmetry.

Investigating the role of superdiffusive currents in laser induced demagnetization of ferromagnets with nanoscale magnetic domains.

Understanding the loss of magnetic order and the microscopic mechanisms involved in laser induced magnetization dynamics is one of the most challenging topics in today's magnetism research. While scattering between spins, phonons, magnons and electrons have been proposed as sources for dissipation of spin angular momentum, ultrafast spin dependent transport of hot electrons has been pointed out as a potential candidate to explain ultrafast demagnetization without resorting to any spin dissipation channel. Here we use time resolved magneto-optical Kerr measurements to extract the influence of spin dependent transport on the demagnetization dynamics taking place in magnetic samples with alternating domains with opposite magnetization directions.

Stochastic current-induced magnetization switching in a single semiconducting ferromagnetic layer.

We show experimental evidence of magnetization switching in a single (Ga,Mn)(As,P) semiconducting ferromagnetic layer, attributed to a strong reduction of the magnetization and the anisotropy due to current injection. The nucleation of magnetization reversal is found to occur even in the absence of a magnetic field and to be both anisotropic and stochastic. Our findings highlight a new mechanism of magnetization manipulation based on spin accumulation in a semiconductor material.

Tuning a Schottky barrier in a photoexcited topological insulator with transient Dirac cone electron-hole asymmetry.

The advent of Dirac materials has made it possible to realize two-dimensional gases of relativistic fermions with unprecedented transport properties in condensed matter. Their photoconductive control with ultrafast light pulses is opening new perspectives for the transmission of current and information. Here we show that the interplay of surface and bulk transient carrier dynamics in a photoexcited topological insulator can control an essential parameter for photoconductivity-the balance between excess electrons and holes in the Dirac cone.

Ultrafast surface carrier dynamics in the topological insulator Bi₂Te₃.

We discuss the ultrafast evolution of the surface electronic structure of the topological insulator Bi(2)Te(3) following a femtosecond laser excitation. Using time and angle-resolved photoelectron spectroscopy, we provide a direct real-time visualization of the transient carrier population of both the surface states and the bulk conduction band. We find that the thermalization of the surface states is initially determined by interband scattering from the bulk conduction band, lasting for about 0.

Ultrafast spin-state photoswitching in a crystal and slower consecutive processes investigated by femtosecond optical spectroscopy and picosecond X-ray diffraction.

We report the spin state photo-switching dynamics in two polymorphs of a spin-crossover molecular complex triggered by a femtosecond laser flash, as determined by combining femtosecond optical pump-probe spectroscopy and picosecond X-ray diffraction techniques. The light-driven transformations in the two polymorphs are compared. Combining both techniques and tracking how the X-ray data correlate with optical signals allow understanding of how electronic and structural degrees of freedom couple and play their role when the switchable molecules interact in the active crystalline medium.

Photo-control of excitation waves in cardiomyocyte tissue culture.

Azobenzene photoswitches were recently reported to control the activity of neural cells and heart beat in leeches. Here, we report photocontrol of excitation of cultured cardiomyocytes that have been made light sensitive by using the addition of azobenzene trimethylammonium bromide (AzoTAB). The trans-isomer of AzoTAB reversibly suppresses spontaneous activity and propagation of excitation waves, whereas the cis-isomer has no detectable effect on the electrical properties of cardiomyocytes.

Successive dynamical steps of photoinduced switching of a molecular Fe(III) spin-crossover material by time-resolved x-ray diffraction.

We investigate the out-of-equilibrium switching dynamics of a molecular Fe(III) spin-crossover solid triggered by a femtosecond laser flash. The time-resolved x-ray diffraction and optical results show that the dynamics span from subpicosecond local photoswitching followed by volume expansion (nanosecond) and thermal switching (microsecond). We present a physical picture of the consecutive steps in the photoswitching of molecular materials.

Polymorphism in the spin-crossover ferric complexes [(TPA)Fe(III)(TCC)]PF6.

We have identified two polymorphs of the molecular complex [(TPA)Fe((III))(TCC)]PF(6) [TPA = tris(2-pyridylmethyl)amine and TCC = 3,4,5,6-tetrachlorocatecholate dianion]: one is monoclinic and the other is orthorhombic. By lowering the temperature both undergo a thermal spin-crossover between a high-spin (S = 5/2) and a low-spin (S = 1/2) state, which we detected by magnetic, optical and X-ray diffraction measurements. The thermal crossover is only slightly shifted between the polymorphs.