Reachability of Communicating Timed Processes

We study the reachability problem for communicating timed processes, both in discrete and dense time. Our model comprises automata with local timing constraints communicating over unbounded FIFO channels. Each automaton can only access its set of local clocks; all clocks evolve at the same rate. Our main contribution is a complete characterization of decidable and undecidable communication topologies, for both discrete and dense time. We also obtain complexity results, by showing that communicating timed processes are at least as hard as Petri nets; in the discrete time, we also show equivalence with Petri nets. Our results follow from mutual topology-preserving reductions between timed automata and (untimed) counter automata.Comment: Extended versio

Forward Analysis and Model Checking for Trace Bounded WSTS

We investigate a subclass of well-structured transition systems (WSTS), the bounded---in the sense of Ginsburg and Spanier (Trans. AMS 1964)---complete deterministic ones, which we claim provide an adequate basis for the study of forward analyses as developed by Finkel and Goubault-Larrecq (Logic. Meth. Comput. Sci. 2012). Indeed, we prove that, unlike other conditions considered previously for the termination of forward analysis, boundedness is decidable. Boundedness turns out to be a valuable restriction for WSTS verification, as we show that it further allows to decide all $\omega$-regular properties on the set of infinite traces of the system

A brief history of selected malaria vaccine and medical interventions pursued by the Swiss Tropical and Public Health Institute and partners, 1943-2021

In order to be successful in global health today, all the long-established European tropical research institutes had to undergo a transition which can be described as "hunter-gatherer" and descriptive approaches during colonial and postcolonial times to a deeper understanding of infection biology and finally to public health interventions from which populations at large can benefit. During the 1980s and 1990s, the Swiss Tropical Institute (today: Swiss Tropical and Public Health Institute, Swiss TPH) based in Basel too has changed its focus from individual medicine to a public health context. This article does not present new scientific data but takes a historical perspective. Its aim is to highlight the above-mentioned transformation by focusing on selected malaria research-cum-action interventions during the crucial period of the 1990s, which were tailored to the social-ecological settings where the disease was endemic. In order for this transformation to be successful, we intend to emphasise the importance of (i) having a fundamental understanding of local transmission; (ii) building and nurturing relationships with partner institutions; and (iii) developing a coherent research portfolio as key elements for researching and applying evidence in malaria control and elimination as part of national malaria control programmes

Hybrid Method for Digits Recognition using Fixed-Frame Scores and Derived Pitch

This paper presents a procedure of frame normalization based on the traditional dynamic time warping (DTW) using the LPC coefficients. The redefined method is called as the DTW frame-fixing method (DTW-FF), it works by normalizing the word frames of the input against the reference frames. The enthusiasm to this study is due to neural network limitation that entails a fix number of input nodes for when processing multiple inputs in parallel. Due to this problem, this research is initiated to reduce the amount of computation and complexity in a neural network by reducing the number of inputs into the network. In this study, dynamic warping process is used, in which local distance scores of the warping path are fixed and collected so that their scores are of equal number of frames. Also studied in this paper is the consideration of pitch as a contributing feature to the speech recognition. Results showed a good performance and improvement when using pitch along with DTW-FF feature. The convergence rate between using the steepest gradient descent is also compared to another method namely conjugate gradient method. Convergence rate is also improved when conjugate gradient method is introduced in the back-propagation algorithm

Pitfalls in the management of infantile renal neoplasia

This article addresses questions posed by a renal mass in early infancy. Are changes required in the standard approach to a renal mass in this age group? Are diagnostic possibilities transformed enough to warrant a change of approach in a setting like this? What are the ‘benign’ lesions that require consideration? What is the physician’s liability in performing a nephrectomy in a patient with a problem like this? A review of the literature suggests that the vast majority of renal space occupying lesions in children of this age are still Wilms’ tumor. Unless diagnostic refinements reach a higher level, the present protocols should be persisted with.Keywords: cystic nephroma, infancy, liability, pyelonephritis, renal mass, Wilms tumor, xanthogranulomatou

Ecology of Aquatic Plant Myriophyllum Spicatum L. New Record to Kurdistan, Erbil, Iraq

This work deals with the study of aquatic plant Eurasian watermilfoil, Myriophyllum spicatum L. new record to Kurdistan, It is submersed aquatic weed that can easily become excessive in growth and maybe a completely choked small shallow pond. The ecological habitats, distribution, growth characteristic, species description, taxonomical status, economically important and other information, including their control in the aquatic ecosystem, are given in the text. In Kurdistan this plant found in several small and shallow ponds, at the edge of the Greater Zab River behind Kapran village near Gwer sub-district, this area is free from ecological and biological studies.  Ecologically the waters are natural, hard, alkaline, rich in nutrients and Cl-1 ions. And contain a certain amount of heavy metal such as (Mg+², Zn+², Cu+², Fe+², Cr+², Cd) but lead (Pb) was not detected

A point mutation in codon 76 of pfcrt of P. falciparum is positively selected for by chloroquine treatment in Tanzania

This study was undertaken to validate the relevance of Chloroquine (CQ) resistance markers pfert76 and pfmdrl86 in an endemic area in Tanzania. After treatment with CQ, recrudescence was distinguished from new infection by msp2 genotyping, and the number of concurrent infection was also determined. The rate of children with recrudescent parasites at day 7 and/or day 14 amounted to a parasitological failure rate of 22.4% using PCR. The mean multiplicity of infection at day 0 was 3.2 (n = 71). The allelic frequencies of the mutated pfert76 and pfmdrl86 were estimated to be 92 and 77%, respectively. Both values exceeded by far the observed frequency of 14% of recrudescent parasites as calculated on the whole analysed parasite population taking multiple infections into account. Although neither mutant allele is of predictive value for parasitological resistance, there is evidence for a role of pfert76 in CQ resistance in the natural parasite population. All wild-type pfert76 alleles were eliminated before day 3, after the onset of CQ treatment and no recrudescent parasite with the wild-type allele was observed at later time points. The discrepancy between the rate of resistant parasites (14%) and the frequency of the mutant pfert76 allele (92%), however, indicates that other polymorphisms and other factors must be involved in CQ resistance. No selective elimination of the pfmdrl86 wild-type allele was observed. © 2002 Elsevier Science B.V. All rights reserved

Interprocedural Reachability for Flat Integer Programs

We study programs with integer data, procedure calls and arbitrary call graphs. We show that, whenever the guards and updates are given by octagonal relations, the reachability problem along control flow paths within some language w1* ... wd* over program statements is decidable in Nexptime. To achieve this upper bound, we combine a program transformation into the same class of programs but without procedures, with an Np-completeness result for the reachability problem of procedure-less programs. Besides the program, the expression w1* ... wd* is also mapped onto an expression of a similar form but this time over the transformed program statements. Several arguments involving context-free grammars and their generative process enable us to give tight bounds on the size of the resulting expression. The currently existing gap between Np-hard and Nexptime can be closed to Np-complete when a certain parameter of the analysis is assumed to be constant.Comment: 38 pages, 1 figur

Dynamics of axialized laser-cooled ions in a Penning trap

We report the experimental characterization of axialization - a method of reducing the magnetron motion of a small number of ions stored in a Penning trap. This is an important step in the investigation of the suitability of Penning traps for quantum information processing. The magnetron motion was coupled to the laser-cooled modified cyclotron motion by the application of a near-resonant oscillating quadrupole potential (the "axialization drive"). Measurement of cooling rates of the radial motions of the ions showed an order-of-magnitude increase in the damping rate of the magnetron motion with the axialization drive applied. The experimental results are in good qualitative agreement with a recent theoretical study. In particular, a classical avoided crossing was observed in the motional frequencies as the axialization drive frequency was swept through the optimum value, proving that axialization is indeed a resonant effect.Comment: 8 pages, 9 figure