On finitely ambiguous B\"uchi automata

Unambiguous B\"uchi automata, i.e. B\"uchi automata allowing only one accepting run per word, are a useful restriction of B\"uchi automata that is well-suited for probabilistic model-checking. In this paper we propose a more permissive variant, namely finitely ambiguous B\"uchi automata, a generalisation where each word has at most $k$ accepting runs, for some fixed $k$. We adapt existing notions and results concerning finite and bounded ambiguity of finite automata to the setting of $\omega$-languages and present a translation from arbitrary nondeterministic B\"uchi automata with $n$ states to finitely ambiguous automata with at most $3^n$ states and at most $n$ accepting runs per word

Congenital azygos pseudocontinuity with right lower intercostal vein

We report the case of a neonate born at 384/7 weeks of gestation with median birth weight and size and in the 75th percentile for head circumference. Routine pregnancy follow up allowed the antenatal discovery of azygos continuation with absence of the inferior vena cava

News from the Universities: Postgraduaat Radiologie van de Vlaamse Universiteiten. Programma 2012-2013

In this presentation, we reported a retrospective study on our experience in CT-guided percutaneous lung biopsy performed by residents having a low or limited previous experience. We compared our results with those obtained by experienced operators and published in large studies of the literature in terms of accuracy and side effects. The study included 229 patients (male: 131 - female: 98 - average age: 65 y) that underwent percutaneous lung biopsy (lesion diameter range : 6,9 to 163 mm - average : 32,3 mm) under CT control from 1 September, 2009, to 11 April, 2011. All biopsies were performed by two residents during their second/third year of residency. A first resident learned from an experienced radiologist in interventional radiology and, after a few weeks, he began to perform biopsies by himself. The ten first biopsies were performed in close supervision of the experienced radiologist. After some months of experience the first resident taught and trained the second resident. Usual indications and contraindications for lung biopsy were applied. Usual technique was used with both 18G fine needle aspiration and 20G co-axial tru-cut needle combined technique under CT fluoroscopic control. In 2 cases of the 229 biopsies, a sample was not obtained due to an immediate pneumothorax. Lesions reported as suspicious of malignancy at pathology, including atypical adenomatous/alveolar hyperplasia, were considered as a false negative biopsy (n = 7) for analysis. Malignant, benign and false negative samples were obtained in 78%, 18% and 4%, respectively. This represents a global accuracy of 94.7%, which is closely similar to other studies (Table I)

Pareto-based application specification for MP-SoC customized run-time management

In an MP-SoC environment, a customized run-time management should be incorporated on top of the basic OS services to globally optimize costs (e.g. energy consumption) across all active applications, according to constraints (e.g. performance, user requirements) and available platform resources. To that end, we have proposed a Pareto-based approach combining a design-time application mapping and platform exploration with a low-complexity run-time manager. This allows to alleviate the OS in its run-time decisison making and to avoid conservative worstcase assumptions. In this paper, we focus on the characterization of the Pareto-based application specification, resulting from our design-time exploration. This specification is essential as input for our run-time manager. A representative video codec multimedia application, simulated on our MP-SoC platform simulator, is used as case study. For the resulting Pareto-based specification, both binary size and performance overhead is negligible

Adjuvant Radiotherapy and 5-Fluorouracil After Curative Resection of Cancer of the Pancreas and Periampullary Region: Phase III Trial of the EORTC Gastrointestinal Tract Cancer Cooperative Group

OBJECTIVE: The survival benefit of adjuvant radiotherapy and 5-fluorouracil versus observation alone after surgery was investigated in patients with pancreatic head and periampullary cancers. SUMMARY BACKGROUND DATA: A previous study of adjuvant radiotherapy and chemotherapy in these cancers by the Gastrointestinal Tract Cancer Cooperative Group of EORTC has been followed by other studies with conflicting results. METHODS: Eligible patients with T1-2N0-1aM0 pancreatic head or T1-3N0-1aM0 periampullary cancer and histologically proven adenocarcinoma were randomized after resection. RESULTS: Between 1987 and 1995, 218 patients were randomized (108 patients in the observation group, 110 patients in the treatment group). Eleven patients were ineligible (five in the observation group and six in the treatment group). Baseline characteristics were comparable between the two groups. One hundred fourteen patients (55%) had pancreatic cancer (54 in the observation group and 60 in the treatment group). In the treatment arm, 21 patients (20%) received no treatment because of postoperative complications or patient refusal. In the treatment group, only minor toxicity was observed. The median duration of survival was 19.0 months for the observation group and 24.5 months in the treatment group (log-rank, p = 0.208). The 2-year survival estimates were 41% and 51%, respectively. The results when stratifying for tumor location showed a 2-year survival rate of 26% in the observation group and 34% in the treatment group (log-rank, p = 0.099) in pancreatic head cancer; in periampullary cancer, the 2-year survival rate was 63% in the observation group and 67% in the treatment group (log-rank, p = 0.737). No reduction of locoregional recurrence rates was apparent in the groups. CONCLUSIONS: Adjuvant radiotherapy in combination with 5-fluorouracil is safe and well tolerated. However, the benefit in this study was small; routine use of adjuvant chemoradiotherapy is not warranted as standard treatment in cancer of the head of the pancreas or periampullary region

Linking transpiration reduction to rhizosphere salinity using a 3D coupled soil-plant model

Soil salinity can cause salt plant stress by reducing plant transpiration and yield due to very low osmotic potentials in the soil. For predicting this reduction, we present a simulation study to (i) identify a suitable functional form of the transpiration reduction function and (ii) to explain the different shapes of empirically observed reduction functions. Methods We used high resolution simulations with a model that couples 3D water flow and salt transport in the soil towards individual roots with flow in the root system. Results The simulations demonstrated that the local total water potential at the soil-root interface, i.e. the sum of the matric and osmotic potentials, is for a given root system, uniquely and piecewise linearly related to the transpiration rate. Using bulk total water potentials, i.e. spatially and temporally averaged potentials in the soil around roots, sigmoid relations were obtained. Unlike for the local potentials, the sigmoid relations were non-unique functions of the total bulk potential but depended on the contribution of the bulk osmotic potential. Conclusions To a large extent, Transpiration reduction is controlled by water potentials at the soil-root interface. Since spatial gradients in water potentials around roots are different for osmotic and matric potentials, depending on the root density and on soil hydraulic properties, transpiration reduction functions in terms of bulk water potentials cannot be transferred to other conditions, i.e. soil type, salt content, root density, beyond the conditions for which they were derived. Such a transfer could be achieved by downscaling to the soilroot interface using simulations with a high resolution process model