The 2-way quantum finite automaton introduced by Kondacs and Watrous[KW97] can accept non-regular languages with bounded error in polynomial time. If we restrict the head of the automaton to moving classically and to moving only in one direction, the acceptance power of this 1-way quantum finite automaton is reduced to a proper subset of the regular languages.In this paper we study two different models of 1-way quantum finite automata. The first model, termed measure-once quantum finite automata, was introduced by Moore and Crutchfield [MC00], and the second model, termed measure-many quantum finite automata, was introduced by Kondacs and Watrous [KW97].We characterize the measure-once model when it is restricted to accepting with bounded error and show that, without that restriction, it can solve the word problem over the free group. We also show that it can be simulated by a probabilistic finite automaton and describe an algorithm that determines if two measure-once automata are equivalent.We prove several closure properties of the classes of languages accepted by measuremany automata, including inverse homomorphisms, and provide a new necessary condition for a language to be accepted by the measure-many model with bounded error. Finally, we show that piecewise testable sets can be accepted with bounded error by a measure-many quantum finite automaton, in the process introducing new construction techniques for quantum automata.

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Although certain preoperative factors are associated with the need to convert a LC for acute cholecystitis, they have limited predictive power. Factors with higher predictive power are obtained only during LC. The need to convert can only be established during an attempt at LC. Preoperative and operative factors associated with total and infectious complications have no predictive power.

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It is not possible to define an evidence-based index of suspicion for ICCs in patients with AM. Diagnostic imaging at presentation accordingly remains mandatory.

Although bactibilia is an important condition of acute cholecystitis, its effect on the course and outcome of the infectious gallbladder disease has rarely been studied, particularly in relation to the laparoscopic procedure. The current study attempts to learn more about the inter-relationship between bactibilia and laparoscopic cholecystectomy during acute cholecystitis. Demographic, preoperative, operative, and postoperative data were prospectively collected in every patient with acute cholecystitis treated in the department of surgery at the Bnai Zion Medical Center, Israel. Intraoperative biliary samples were collected under aseptic conditions at the time of operation for bacteriologic examination and were routinely cultured in aerobic and anaerobic media for 3 days. The study population was divided into culture-positive and culture-negative groups, and the collected parameters were compared between the groups. Age over 60 years, a palpable gallbladder, temperature over 37.5 degrees C, a white blood cell (WBC) count of more than 12,000/cc(3), and serum alkaline phosphatase higher than 100 U/dL were all found to be factors capable of predicting bactibilia. Bactibilia was a significant factor associated with total, as well as infectious, operative complications. Bactibilia is considered to indicate an advanced stage of acute cholecystitis. In cases of laparoscopic cholecystectomy for infectious gallbladder disease, bactibilia is strongly associated with total, as well as local, infectious complications. Preoperative conditions such as older age, elevated temperature, a palpable gallbladder, elevated WBC count, and elevated serum levels of alkaline phosphatase can serve as predictors of bactibilia and its consequent complications. Although the sensitivity and specificity of the predictive factors for bactibilia are limited to 63% and 67%, respectively, in their presence during acute cholecystitis, conservative wide-spectrum antibiotics as the first-line therapy is appropriate, and, upon regimen failure, laparoscopic surgery by an experienced surgeon is indicated as the adjusted therapy.