Training of quantum circuits on a hybrid quantum computer.

Generative modeling is a flavor of machine learning with applications ranging from computer vision to chemical design. It is expected to be one of the techniques most suited to take advantage of the additional resources provided by near-term quantum computers. Here, we implement a data-driven quantum circuit training algorithm on the canonical Bars-and-Stripes dataset using a quantum-classical hybrid machine. The training proceeds by running parameterized circuits on a trapped ion quantum computer and feeding the results to a classical optimizer. We apply two separate strategies, Particle Swarm and Bayesian optimization to this task. We show that the convergence of the quantum circuit to the target distribution depends critically on both the quantum hardware and classical optimization strategy. Our study represents the first successful training of a high-dimensional universal quantum circuit and highlights the promise and challenges associated with hybrid learning schemes.

Intestinal transit in dogs is accelerated by volume distension during fat-induced jejunal brake.

Intestinal transit is accelerated by volume distension and slowed by nutrient load. We hypothesized that the accelerating effect of volume distension might overcome the slowing effect of nutrient. To test this hypothesis, we compared intestinal transit in five dogs equipped with duodenal and mid-intestinal fistulas. The proximal half of the small intestine was perfused with 60 mM oleate, while the distal half of the small intestine was either perfused with buffer (with distension) or left unperfused (without distension). We found that intestinal transit was slowed by oleate (with marker recovery reduced from 85.8 +/- 5.3 to 39.4 +/- 7.5%) (P < 0.01) and that volume distension accelerated intestinal transit so that marker recovery increased from 39.4 +/- 7.5 without distension to 60.8 +/- 6.3% with distension (P < 0.05). We concluded that intestinal transit is accelerated by volume distension during fat-induced jejunal brake.

Acute inflammation causes epithelial invasion and mucosal destruction in experimental shigellosis.

The gram-negative pathogen Shigella flexneri causes bacillary dysentery, an invasive disease of the human colonic mucosa. A major characteristic of the infectious process is the occurrence of an acute inflammatory reaction of mucosal tissues which is generally consequence of primary invasion and destruction of colonic epithelial cells by the pathogen. Confirming in vitro demonstration that S. flexneri is unable to invade the apical pole of colonic cells and that polymorphonuclear (PMN) cells may assist them in reaching the basal side of epithelial cells where they can invade, we have provided here in vivo evidence that S. flexneri enters the epithelial barrier essentially through the dome of lymphoid follicles at the early stage of infection and that subsequent invasion and destruction of the epithelium is primarily due to immigration of leukocytes, particularly PMN that destroy cohesion of the epithelial barrier. These conclusions are based on experiments carried out in infected rabbit ligated intestinal loops, with some animals treated by an anti-CD18 monoclonal antibody that blocked immigration of leukocytes into infected tissues.