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We present "Diagrams of States", a way to graphically represent and analyze how quantum information is elaborated during the execution of quantum circuits. This introductory tutorial illustrates the basics, providing useful examples of quantum computations: elementary operations in single-qubit, two-qubit and three-qubit systems, immersions of gates on higher dimensional spaces, generation of single and multi-qubit states, procedures to synthesize unitary, controlled and diagonal matrices. To perform the analysis of quantum processes, we directly derive diagrams of states from physical implementations of quantum circuits associated to the processes. Complete diagrams are then rearranged into simplified diagrams, to visualize the overall effects of computations. Conversely, diagrams of states help to conceive new quantum algorithms, by schematically describing desired manipulations of quantum information with intuitive diagrams and then by guessing the equivalent complete diagrams, from which the corresponding quantum circuit is obtained effortlessly. Related examples and analysis of complex algorithms will be provided in future works, for whose comprehension this first tutorial offers the necessary introduction., Comment: 29 pages, 25 figures, to be published in IJUC - International Journal of Unconventional Computing

BACKGROUND AND STUDY AIM: The aim of this study was to assess the prevalence of nonpolypoid lesions (NPLs) in Italy and their risk of containing neoplasia or advanced histology. PATIENTS AND METHODS: This was a multicenter cross-sectional observational study on consecutive patients undergoing total colonoscopy over a 3-month period in 80 Italian centers. RESULTS: In all, 27,400 total colonoscopies were analyzed. Cancer was diagnosed in 801 patients (2.9 %). A total of 6553 precancerous lesions were detected in 5609 patients. Of these, 4154 patients (74.1 %) had polypoid lesions and 1455 patients (25.9 %) had NPLs. Therefore, the prevalence of NPLs was 5.3 % (95 %CI 5.0 - 5.6). NPLs larger than 10 mm were detected in 254 patients (17.5 %). NPLs were more predominant in the proximal colon (OR 2.92, 95 %CI 2.56 - 3.43; P < 0.0001 vs. polypoid lesions). Neoplastic tissue was diagnosed in 79.0 % and advanced histology (high-grade intraepithelial neoplasia or more) in 20.9 % of resected lesions. The risk of advanced histology was similar for polypoid and nonpolypoid lesions when adjusted for size. Depressed lesions had the highest risk of advanced histology (OR 10.56, 95 %CI 6.02 - 18.55; P < 0.0000 vs. flat-elevated). Age was an independent predictor of both neoplasia and advanced histology ( P = 0.0001). CONCLUSIONS: NPLs are relatively common in the Italian population, with a prevalence similar to that in other Western series. NPLs are not more aggressive than polypoid lesions, except for those with depressed morphology. Georg Thieme Verlag KG Stuttgart. New York.

We study the dynamics of a spin coupled to an oscillating magnetic field, in the presence of decoherence and dissipation. In this context we solve the master equation for the Landau-Zener problem, both in the unitary and in the irreversible case. We show that a single spin can be "magnetized" in the direction parallel to the oscillating bias. When decay from upper to lower level is taken into account, hysteretic behavior is obtained., Comment: 26 pages, 12 figures

We have studied critically the validity, reproducibility, and possible limitations of the rat hind limb perfusion technique under constant flow conditions. Of all the variables studied, bolus size, order of dose administration, perfusion pressure, rat temperature, perfusate temperature, perfusate type, rat age, and rat sex, we found that time is an important limitation in the use of this technique when oxygenated standard physiological salt solutions are used. This limitation may be minimized when a colloid is added to the perfusing medium or eliminated when the perfusion time is no longer than 60 min.

We introduce different strategies to enhance photon generation in a cavity within the Rabi model in the ultrastrong coupling regime. We show that a bang-bang strategy allows one to enhance the effect up to 1 order of magnitude with respect to simply driving the system in resonance for a fixed time. Moreover, up to about another order of magnitude can be gained by exploiting quantum optimal control strategies. Finally, we show that such optimized protocols are robust with respect to systematic errors and noise, paving the way to future experimental implementations of such strategies.

Background and objectives The aim of this prospective, randomized study was to compare the standard regimen of midazolam and pethidine administered by the gastroenterologist versus patient controlled sedation with a propofol–fentanyl mixture during upper gastrointestinal tract endoscopic ultrasonography. Our primary end-points were patient satisfaction and patient cooperation assessed by endoscopist. Methods Fifty-four consecutive patients, undergoing endoscopic ultrasonography, received sedation with midazolam and pethidine (Group M: n = 27) or propofol and fentanyl (Group P: n = 27). Group M: pethidine 0.7 mg/kg midazolam 0.04 mg/kg before examination; boluses of same drugs if the sedation was insufficient plus a sham patient controlled sedation analgesia; Group P: propofol 17 mg plus fentanyl 15 μg before examination and a patient controlled sedation analgesia pump containing 170 mg propofol plus 150 μg fentanyl injecting 0.5 ml every time the patient pressed the button (no “lock out”). Boluses of 1 ml of the same mixture if the sedation was insufficient. Results Group M: mean dosage of pethidine and midazolam 88.6 and 5 mg, respectively. Group P: mean dosage of propofol and fentanyl 119.7 mg and 106 μg, respectively. Both groups were similar for duration and difficulty of the procedure, the grade of sedation (Observer's Assessment of Alertness/Sedation Score) and judgement by endoscopist and patient about cooperation and satisfaction. The only difference between groups was about the extra boluses administered during the procedure. Conclusion This study demonstrated that a patient controlled sedation analgesia with propofol and fentanyl is an effective and safe technique for upper gastrointestinal tract endoscopic ultrasonography procedures and results in a high level of satisfaction both for patients and operator.