Development of a method based on ATR-FTIR spectroscopy to detect maple syrup adulterated with added syrups.

Background: Food adulteration is a global concern, whether it takes place intentionally or incidentally. In Canada, maple syrup is susceptible to being adulterated with cheaper syrups such as corn, beet, cane syrups, and many more due to its high price and economic importance.

Results: In this study, the use of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy was investigated to detect maple syrups adulterated with 15 different sugar syrups at different concentration levels.

Patterns of bacterial motility in microfluidics-confining environments.

Understanding the motility behavior of bacteria in confining microenvironments, in which they search for available physical space and move in response to stimuli, is important for environmental, food industry, and biomedical applications. We studied the motility of five bacterial species with various sizes and flagellar architectures (, , , , and ) in microfluidic environments presenting various levels of confinement and geometrical complexity, in the absence of external flow and concentration gradients. When the confinement is moderate, such as in quasi-open spaces with only one limiting wall, and in wide channels, the motility behavior of bacteria with complex flagellar architectures approximately follows the hydrodynamics-based predictions developed for simple monotrichous bacteria.

Using the fringe field of a clinical MRI scanner enables robotic navigation of tethered instruments in deeper vascular regions.

Navigating tethered instruments through the vasculatures to reach deeper physiological locations presently inaccessible would extend the applicability of many medical interventions, including but not limited to local diagnostics, imaging, and therapies. Navigation through narrower vessels requires minimizing the diameter of the instrument, resulting in a decrease of its stiffness until steerability becomes unpractical, while pushing the instrument at the insertion site to counteract the friction forces from the vessel walls caused by the bending of the instrument. To reach beyond the limit of using a pushing force alone, we report a method relying on a complementary directional pulling force at the tip created by gradients resulting from the magnetic fringe field emanating outside a clinical magnetic resonance imaging (MRI) scanner.

Relative influence of watershed and geomorphic features on nutrient and carbon fluxes in a pristine and moderately urbanized stream.

Streams are important sites of elemental transformations due to the relatively high contact rates between flowing water and biogeochemically reactive sediments. Increased urbanization typically results in higher nutrient and carbon (C) inputs to streams from their watersheds and increased flow rates due to modification in channel form, reducing within stream net retention and increasing downstream exports. However, less is known on how moderate urbanization might influence the joint processing of C, nitrogen (N), and phosphorus (P) in streams or the relative influence of changes in watershed and stream features on their fluxes.

Magnetic Resonance Navigation for Targeted Embolization in a Two-Level Bifurcation Phantom.

This work combines a particle injection system with our proposed magnetic resonance navigation (MRN) sequence with the intention of validating MRN in a two-bifurcation phantom for endovascular treatment of hepatocellular carcinoma (HCC). A theoretical physical model used to calculate the most appropriate size of the magnetic drug-eluting bead (MDEB, 200 μm) aggregates was proposed. The aggregates were injected into the phantom by a dedicated particle injector while a trigger signal was automatically sent to the MRI to start MRN which consists of interleaved tracking and steering sequences.

MRI-Compatible Injection System for Magnetic Microparticle Embolization.

Objective: Dipole field navigation and magnetic resonance navigation exploit B magnetic fields and imaging gradients for targeted intra-arterial therapies by using magnetic drug-eluting beads (MDEBs). The strong magnetic strength (1.5 or 3 T) of clinical magnetic resonance imaging (MRI) scanners is the main challenge preventing the formation and controlled injection of specific-sized particle aggregates.

Selective embolization with magnetized microbeads using magnetic resonance navigation in a controlled-flow liver model.

Purpose: The purpose of this study was to demonstrate the feasibility of using a custom gradient sequence on an unmodified 3T magnetic resonance imaging (MRI) scanner to perform magnetic resonance navigation (MRN) by investigating the blood flow control method in vivo, reproducing the obtained rheology in a phantom mimicking porcine hepatic arterial anatomy, injecting magnetized microbead aggregates through an implantable catheter, and steering the aggregates across arterial bifurcations for selective tumor embolization.

Materials And Methods: In the first phase, arterial hepatic velocity was measured using cine phase-contrast imaging in seven pigs under free-flow conditions and controlled-flow conditions, whereby a balloon catheter is used to occlude arterial flow and saline is injected at different rates. Three of the seven pigs previously underwent selective lobe embolization to simulate a chemoembolization procedure.

In vivo demonstration of magnetic guidewire steerability in a MRI system with additional gradient coils.

Purpose: To assess the ability to control the steering of a modified guidewire actuated by the magnetic force of a magnetic resonance imaging system with additional gradient coils for selective arterial catheterization in rabbits.

Methods: Selective catheterizations of the right renal artery, left renal artery, superior mesenteric artery, and iliac artery were performed on two rabbits. A 3D magnetic force was applied onto a magnetic bead placed at the tip of a guidewire.