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The ArcturusXT™ is a unique microdissection system that combines Laser Capture Microdissection (LCM) and Ultraviolet (UV) Laser Cutting in one instrument. The solid-state IR laser, exclusive to the ArcturusXT microdissection system, delivers a gentle capture technique, maximizing biomolecule integrity and ideal for single cells and small number of cells. The solid-state UV laser delivers unprecedented speed and precision, ideal for dense tissue structures and for capturing large number of cells.

Electronic confinement at nanoscale dimensions remains a central means of science and technology. I will describe a novel method for producing electronic nanostructures at the interface between two normally insulating oxides, LaAlO3 and SrTiO3. These structures and devices are “written” by a conductive atomic force microscope probe in ambient conditions at room temperature, and can be erased and reconfigured. The spatial dimensions of these structures are comparable to the width of a single-wall carbon nanotube (~2 nm). A wide variety of devices can be created, including nanowires, tunnel junctions, diodes, field-effect transistors, single-electron transistors, superconducting nanowires, quantum dots and nanoscale THz emitters and detectors. This new, on-demand nanoelectronics platform has the potential for widespread scientific and technological exploitation.

Water-rock interactions in the Earth's crust often modify the pore space and permeability of rocks, soils, and sediments, changing the way fluids flow in the subsurface. Crucially, such geochemical reactions are often controlled by nano-scale processes. In this study, we use atomic force microscopy to examine dissolution rates of limestone; crucially, our measurements show that the rate of mineral dissolution within micron-size pores is much lower than the rate of dissolution on surrounding polished mineral surfaces. In addition, we use numerical simulations to show that this difference cannot be explained using a diffusion - surface reaction model. We propose that the observed variation in reaction rates could instead be due to the elevated density of reactive high curvature features on the polished surfaces. These features can strongly affect local interfacial free energy, making surfaces more prone to dissolution. As a result, polished surfaces should be more reactive than pore surfaces that have effectively been smoothed during prolonged contact with natural fluids. As standard rate experiments routinely use polished and powdered samples, our findings may help to explain the widely reported discrepancy between lab and field-based dissolution rates.

We propose an alternative method to compute the entropy production of a classical underdamped nonequilibrium system in a continuous phase space. This approach has the advantage that it is not necessary to distinguish between even and odd-parity variables. We show that the method leads to the same local entropy production as in previous studies while the differential entropy production along a stochastic trajectory turns out to be different. This demonstrates that the differential entropy production in continuous phase space systems is not uniquely defined.
See also: arxiv 1305.0655, not yet published