I know there are some "quantum versions" of hand-writing recognition algorithms which have been proposed using quantum neural networks. Example: "Recognition of handwritten numerals by Quantum Neural Network with fuzzy features" (J Zhou, 1999). Also, recently by Rebentrost et al.: "A Quantum Hopfield Neural Network" presents an application of their method as a genetic sequence recognizer.
What are some other proposed applications of quantum neural networks whose given solutions provide considerable improvement over the corresponding classical version of the neural network in terms of accuracy? Also, have any of those proposed solutions been programmed/simulated?
Please note that I'm looking for research papers which specifically demonstrate some applications of quantum neural networks and which provide a significant improvement over the corresponding classical neural networks.