A linear translation from CTL* to the first-order modal μ -calculus

The modal μ-calculus is a very expressive temporal logic. In particular, logics such as LTL, CTL and CTL* can be translated into the modal μ-calculus, although existing translations of LTL and CTL* are at least exponential in size. We show that an existing simple first-order extension of the modal μ-calculus allows for a linear translation from LTL. Furthermore, we show that solving the translated formulae is as efficient as the best known methods to solve LTL formulae directly.     

Bruck syndrome: neonatal presentation and natural course in three patients

Three unrelated patients with congenital arthrogryposis and brittle bones, the main neonatal signs of Bruck syndrome, are presented. In infancy and early childhood recurrent fractures of ribs and long bones and persistent Wormian bones in the calvarium are reminiscent of osteogenesis imperfecta (OI) even with white sclerae, normal dental quality and normal hearing as important clinical negatives. The diagnosis was made before two years of age in two, and in adolescence in the third patient. The latter's radiologically documented long-term natural course reveals slow progressivity of osteopenia and growth deficiency, worsening tendon contractures and pterygia in addition to increasing spine and pelvis deformation. Mental development remains normal. Bruck syndrome is monogenic and probably due to homozygosity of an as yet unidentified gene. As no alteration in the collagens I and III is detected and molecular screening reveals no mutation in the COL1A1 and COL1A2 genes, the pathogenesis of this severe disorder of connective tissue remains largely unknown.     

A syntactic commutativity format for SOS

Considering operators defined using Structural Operational Semantics (SOS), commutativity axioms are intuitive properties that hold for many of them. Proving this intuition is usually a laborious task, requiring several pages of boring and standard proof. To save this effort, we propose a syntactic SOS format which guarantees commutativity for a set of composition operators.     

Rhizomucor pusillus mucormycosis combined with chlamydiosis in an African grey parrot (Psittacus erithacus erithacus)

This paper describes a case of mucormycosis combined with chlamydiosis in an African grey parrot (Psittacus erithacus erithacus). The clinical signs included diarrhoea, an unsteady gait and a twisted neck. Smears of the spleen, liver and contents of the cloaca stained strongly positive for Chlamydia species. Histologically, hyphae typical of Zygomycetes were observed invading through the walls of blood vessels of the spleen. Rhizomucor pusillus was isolated as a pure culture from the intestines, lungs and liver.     

Verification of a sliding window protocol in μCRL and PVS

We prove the correctness of a sliding window protocol with an arbitrary finite window size n and sequence numbers modulo 2n. The correctness consists of showing that the sliding window protocol is branching bisimilar to a queue of capacity 2n. The proof is given entirely on the basis of an axiomatic theory, and has been checked in the theorem prover PVS. Received November 2004 Revised June 2005 Accepted July 2005 by J. V. Tucker     

Cellular vaccines

This project is devoted to the development of novel cellular vaccines designed to treat cancer patients. These cellular vaccines present and enhance immunogens, which will elicit a potent immune response. The goal is to achieve safe and effective immune reaction against the patient's own tumour. (1) Autologous cellular vaccines are prepared by processing circulating blood mononuclear cells outside of the patient's body (ex vivo) to differentiate them into antigen-presenting cells (APCs). Monocyte-derived APCs (MD-APCs) are then grown in the presence of exogenous target antigens (tumour cell debris, or apoptotic bodies) to become fully mature APCs. (2) Functionality for antigen presentation to T cells of ex vivo MD-APCs is evaluated in vivo. (3) Cellular vaccines are tested in selected rodent animal models. Efficiency and immune response are monitored in pertinent experimental systems for cancer. Pharmacological data are generated for clinical investigation. Tolerance and biologic effects are documented in primates. (4) The first clinical trials on cancer patients are taking place in 1998 on melanoma and prostate cancer to validate the concept. Specialized cell processors with dedicated software and standardized controls are being developed and used for the preparation of cellular vaccines. (5) The evaluation of new non-viral vectors and the validation of new non-viral transfection methods of mononuclear cells with marker genes is in progress and will lead to the ex vivo transfection of genes coding for immunostimulating cytokines or for tumour antigens in MD-APCs. Efficiency will be validated in vitro and in animal models. The ex vivo and animal model studies validate the clinical relevance of this new cellular immunotechnology. Clinical validation of individual autologous cellular vaccines in specific indications for which no treatment is presently available will allow the development of cellular and gene immunotherapy for other types of cancers.     

Sepsis and serum cytokine concentrations

Hematological and plasma chemistry parameters were measured in 129 juvenile white storks (Ciconia ciconia), either wild or captive bred, April to June 1994. Wild storks were members of a colony in the Lozoya River Valley, Madrid, Spain. Red blood cells count, packed cell volume and hemoglobin increased significantly with age. White blood cells count, lymphocytes count and platelets decreased with age. Total solids, total proteins, fibrinogen, albumin, alpha, beta, gamma-globulins and urea increased with age. Differences between captive and wild birds were not notable.     

Verification of Hypertorus Communication Grids by Infinite Petri Nets and Process Algebra

A model of a hypertorus communication grid has been constructed in the form of an infinite Petri net. A grid cell represents either a packet switching device or a bioplast cell. A parametric expression is obtained to allow a finite specification of an infinite Petri net. To prove properties of an ideal communication protocol, we derive an infinite Diophantine system of equations from it, which is subsequently solved. Then we present the programs htgen and ht-mcrl2-gen, developed in the C language, which generate Petri net and process algebra models of a hypertorus with a given number of dimensions and grid size. These are the inputs for the respective modeling tools Tina and mCRL2, which provide model visualization, step simulation, state space generation and reduction, and structural analysis techniques. Benchmarks to compare the two approaches are obtained. An ad-hoc induction-like technique on invariants, obtained for a series of generated models, allows the calculation of a solution of the Diophantine system in a parametric form. It is proven that the basic solutions of the infinite system have been found and that the infinite Petri net is bounded and conservative. Some remarks regarding liveness and liveness enforcing techniques are also presented.      

Operator dependency of arterial input function in dynamic contrast-enhanced MRI

Objective

To investigate the effect of inter-operator variability in arterial input function (AIF) definition on kinetic parameter estimates (KPEs) from dynamic contrast-enhanced (DCE) MRI in patients with high-grade gliomas.

Methods

The study included 118 DCE series from 23 patients. AIFs were measured by three domain experts (DEs), and a population AIF (pop-AIF) was constructed from the measured AIFs. The DE-AIFs, pop-AIF and AUC-normalized DE-AIFs were used for pharmacokinetic analysis with the extended Tofts model. AIF-dependence of KPEs was assessed by intraclass correlation coefficient (ICC) analysis, and the impact on relative longitudinal change in K^trans was assessed by Fleiss’ kappa (κ).

Results

There was a moderate to substantial agreement (ICC 0.51–0.76) between KPEs when using DE-AIFs, while AUC-normalized AIFs yielded ICC 0.77–0.95 for K^trans, k_ep and v_e and ICC 0.70 for v_p. Inclusion of the pop-AIF did not reduce agreement. Agreement in relative longitudinal change in K^trans was moderate (κ = 0.591) using DE-AIFs, while AUC-normalized AIFs gave substantial (κ = 0.809) agreement.

Discussion

AUC-normalized AIFs can reduce the variation in kinetic parameter results originating from operator input. The pop-AIF presented in this work may be applied in absence of a satisfactory measurement.