Publications by authors named "Juan Staforelli"

Honey adulteration is a common practice that affects food quality and sale prices, and certifying the origin of the honey using non-destructive methods is critical. Guindo Santo and Quillay are fundamental for the honey production of Biobío and the Ñuble region in Chile. Furthermore, Guindo Santo only exists in this area of the world.

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Correction for 'Controlling the dynamics of colloidal particles by critical Casimir forces' by Alessandro Magazzù et al., Soft Matter, 2019, 15, 2152-2162, DOI: 10.1039/C8SM01376D.

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Critical Casimir forces can play an important role for applications in nano-science and nano-technology, owing to their piconewton strength, nanometric action range, fine tunability as a function of temperature, and exquisite dependence on the surface properties of the involved objects. Here, we investigate the effects of critical Casimir forces on the free dynamics of a pair of colloidal particles dispersed in the bulk of a near-critical binary liquid solvent, using blinking optical tweezers. In particular, we measure the time evolution of the distance between the two colloids to determine their relative diffusion and drift velocity.

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A noncontact infrared (IR) imaging-based methodology and signal recovery tools are applied on an enzyme reaction as a test target. The method is implemented by a long-wave (8-12 μm) IR microbolometer imaging array and a germanium-based IR optical vision. The reaction is carried out by the glucokinase, which produces a rapid exothermal release of energy that is weak, and, even worse, the IR video captured by the uncooled microbolometer detector is affected by spatial and temporal noise with specific complexities.

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In this paper, a comprehensive spatio-spectral and temporal analysis for Chromobacterium violaceum colonies is reported. A hyperspectral imaging (HSI) system is used to recover the spectral signatures of pigment production in a non-homogeneous media with high spectral resolution and high sensitivity in vivo, without destructing the sample. This non-contact sensing technique opens avenues to study the temporal growing of a specific section in the bacterial colony.

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High-speed cameras are reliable alternatives for the direct characterization of optical trap force and particle motion in optical tweezers setups, replacing indirect motion measurements often performed by quadrant detectors. In the present approach, subpixel motion data of the trapped particle is retrieved from a high-speed low-resolution video sequence. Due to the richness structure of motion diversity of microscopic trapped particles, which are subjected to a Brownian motion, we propose to also use the obtained motion information for tackling the inherent lack of resolution by applying superresolution algorithms on the low-resolution image sequence.

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