From Event-B models to Dafny code contracts

International audienceThe constructive approach to software correctness aims at formal modelling and verification of the structure and behaviour of a system in different levels of abstraction. In contrast, the analytical approach to software verification focuses on code level correctness and its verification. Therefore it would seem that the constructive and analytical approaches should complement each other well. To demonstrate this idea we present a case for linking two existing verification methods, Event-B (constructive) and Dafny (analytical). This approach combines the power of Event-B abstraction and its stepwise refinement with the verification capabilities of Dafny. We presented a small case study to demonstrate this approach and outline of the rules for transforming Event-B events to Dafny contracts. Finally, a tool for automatic generation of Dafny contracts from Event-B formal models is presented

Perinatal Hypoxic-ischemic Encephalopathy: Acute Period And Outcome [encefalopatia Hipóxico-isquêmica Em Recém-nascidos A Termo: Aspectos Da Fase Aguda E Evolução]

Ninety four neonates with hypoxic ischemic encephalopathy HIE attended at the University of Ribeirão Preto since 1982 were studied in terms of the neurological alterations during the acute phase and outcome over a mean period of 47 months. From 43 newborns with HIE I, 40 recovered within 96 hours and 3 died. Among 40 infants with HIE II, 37 5% recovered within the first week, and the others continued abnormal beyond the 7 th day. All 11 infants with HIE III died before the second month of life. The HIE I group had no motor sequelae. Among the HIE II group, 34 5% showed cerebral palsy and 17.7% neuromotor retardation. 80.0% of those with sequelae persisted abnormal beyond 7 th day of life, during the acute phase of the HIE. Epilepsy occurred in 17.5% of cases with HIE grade II, only among those with neuromotor sequelae The IQ test did not show statistically significant difference between the HIE I, II without motor sequelae and the control groups. The authors reaffirm the value of the findings in the acute phase of HIE on the outcome of these patients.554771779André, M., Vert, P., Debruille, C.H., Diagnostic et evolution de la souffrance cerebrale chez les nouveau-nés ayant presents des signes d'hypoxie foetale: Étude prospective (1978) Arch Fr Ped, 35, pp. 23-36Apgar, V., A proposal for a new method of evaluation of the newborn infant (1953) Anesth Analg, 32, pp. 260-267Bergamasco, B., Benna, P., Ferrero, P., Gavinelli, R., Neonatal hypoxia and epileptic risk: A clinical prospective study (1984) Epilepsia, 25, pp. 131-136D'Souza, S.W., Richards, B., Neurological sequelae in newborn babies after perinatal asphyxia (1978) Arch Dis Child, 53, pp. 564-569Diament, A.J., (1976) Evoluc+ (Combining ogonek)Ão Neurológica do Lactente Normal, , São Paulo. EDARTFenichel, G.M., Hypoxi/Ischemic encephaLopathy in the newborn (1983) Arch Neurol, 40, pp. 261-266Fenichel, G.M., Webster, D.L., Wong, W.K.T., Intracranial hemorrhage in the term newborn (1984) Arch NeuroL, 41, pp. 30-34Finer, N., Robertson, C.M., Richards, R.T., Pinnel, L.E., Peters, K.L., Hypoxic-ischemic encephalopathy in term neonates: Perinatal factors and outcome (1981) J Pediatr, 98, pp. 112-117Funayama, C.A.R., (1990) Encefalopatia Hipóxico-isquêmica PerinatalAspectos Epidemiológicos, Neurológicos da Fase Aguda e Evolutivos, , Tese - Faculdade de Medicina de Ribeuão Preto da Universidade de Sāo Paulo Ribeirão PretoFunayama, C.A.R., Moura-Ribeiro, M.V.L., Gonçalves, A.L., Encefalopatia hipóxico-isquêmica perinatal: Aspectos epidemiológicos (1991) Pediatria, 67, pp. 371-374Gherpelli, J.L.D., Ferieira, H., Costa, H.P.F., Neurological follow-up of small-for- Gestational age newborn infants: A study of risk factors related to prognosis at one year of age (1993) Arq Neuropsiquiatr, 51, pp. 50-58Lefèvre, A.B., (1972) Exame Neurológico Evolutivo, , São Paulo: SarvierLevene, M.I., Grindulis, H., Sands, C., Moore, J.R., Comparation of two methods of predicting outcome in perinatal asphyxia (1986) Lancet, 1, pp. 67-68Lombroso, C.T., Prognosis in neonatal seizures (1983) Adv Neurol, 34, pp. 101-113Michaelis, R., Shulte, F.J., Nolte, R., Motor behaviour of small-for-gestational age newborn infants (1970) J Pediatr, 76, pp. 208-213Nelson, K.B., Ellenberg, J.H., Neonatal signs as predictors of cerebral palsy (1979) Pediatrics, 64, pp. 225-232Robertson, C.M., Finer, N., Term infants with hypoxic-ischemic encephalopathy: Outcome at 3,5 years (1985) Dev Med Child Neurol, 27, pp. 437-484Robertson, C.M., Finer, N., Grace, M.G., School perfomance of survivors of neonatal encephalopathy associated with birth asphyxia at term (1989) J Pediatr, 114, pp. 753-760Suint-Anne Dargassies, S., (1977) Desarollo Neurologico del Recien Nacido de Termino y Prematuro, , Buenos Aires: Médica PanamericanaSarnat, H.B., Sarnat, M.S., Neonatal encephalopathy following fetal distress (1976) Arch Neurol, 33, pp. 696-705Scher, M.S., Aso, K., Begarly, M.E., Hamid, M.Y., Steppe, D.A., Painter, M.J., Electrographic seizures in preterm and full-term neonates: Clinical correlates associated brain lesions, and risk for neurologic sequelae (1993) Pediatrics, 91, pp. 128-134Terman, L.M., Merrill, M.A., (1973) Stanford-Binet Intelligence Scale (Form L-M) Manual for the 3 rd Revision. Norms Edition, , Boston: Houghton MifflinVan Kranen-Mastenbroek, V.H.D.M., Folmer, K.B., Kingma, H., Postural behavior of term SGA and AGA newborn infants (1993) Dev Med Child Neurol, 35, pp. 516-524Volpe, J.J., (1995) Neurology of the Newborn. 3 a. Ed, pp. 314-348. , Philadelphia: SaundersZdanska-Brincken, M., Wolánski, N., A graph method for the evaluation of motor development in infants (1969) Dev Med Child Neurol, 11, pp. 228-24

Diversidade de espécies dos gêneros de Crematogaster, Gnamptogenys e Pachycondyla (Hymenoptera: Formicidae) e complementaridade dos métodos de coleta durante a estação seca numa estação ecológica no estado do Pará, Brasil Diversity of species of the genera Crematogaster,Gnamptogenys and Pachycondyla, (Hymenoptera: Formicidae) and complementarity of sampling methods during the dry season in an ecological station in the Brazilian state of Pará

As formigas são muito usadas em programas de inventários e monitoramentos, resultando em grande quantidade de material coletado com vários métodos, limitações financeiras e na falta de taxonomos para vários táxons. Para contribuir na elaboração de protocolos alternativos, analisamos a complementaridade de dois métodos de amostragem na detecção da riqueza de espécies. Em seis parcelas de 1 km² distribuídas em 33.000 ha de floresta primária, investigamos a diversidade e a freqüência das espécies de Crematogaster,Gnamptogenys e Pachycondyla, como parte do protocolo de formigas de serapilheira do Projeto TEAM. Em cada parcela, quatro transectos de 100 m foram instalados. Dez sub-amostras foram efetuadas por transecto, usando extrator de Winkler e armadilha de fosso. Registramos 36 espécies, sendo 15 novos registros para o Pará e 29 para a área de estudo. Dezessete espécies foram comuns aos dois métodos, onze foram capturadas com armadilhas de fosso e oito com Winkler. As proporções de espécies representadas por um indivíduo ("singletons") foram altas para ambos os métodos (> 0,4). Dezenove espécies foram coletadas por apenas um método e três foram representadas por apenas um indivíduo em cada método. A análise de ordenação (escalonamento multidimensional semi-híbrido) revelou diferenças na estrutura das comunidades de formigas obtidas pelos dois métodos de amostragem. Houve um efeito de complementaridade entre os dois métodos para a obtenção de um levantamento mais completo da riqueza de espécies, significando que ambos devem ser usados no protocolo. Outros recursos, como a rarefação e/ou diluição das amostras são recursos a serem avaliados em futuras investigações.<br>Ants are largely used for monitoring and inventory programs, resulting in great amounts of material sampled with several methodologies, financial limitations and lack of experts to do the taxonomy of many taxa. To contribute for the elaboration of alternative protocols, we analyzed the complementarity of two sampling methods in the detection of species richness. In 6 plots of 1 km² distributed in an area of 33,000 ha of continuous primary forest, in the Brazilian state of Pará, the diversity and the frequency of species of genera Crematogaster,Gnamptogenys and Pachycondyla were investigated, as part of the "Ant methodology Protocol" of the Project TEAM. Using the Winkler extractor and pitfall traps, 10 sub-samples were collected per transect. In each plot, 4 transects of 100 m were installed. We registered 36 species, and 15 are new records for the state, and 29 for the study site. Seventeen species were common to both sampling methods, 11 were captured with pitfall and 8 with Winkler. The proportions of singletons were high for both methods (>0,4). Nineteen species were captured by only one method and three were represented by only one individual in both methods. Ordination analysis (SSH, Semi-Strong Hybrid Multi-Dimensional Scaling) indicated differences in community structure between both sampling methods. There was a complementarity's effect between these two methods in order to obtain a more complete inventory of the species richness, indicating that both must be used in the protocol. Other resources like rarefaction and/or sample dilution must be evaluated in future investigations

Hiperglicinemia não cetótica: estudo de um caso

A hiperglicinemia não cetótica é erro inato do metabolismo que se manifesta por crises epilépticas de difícil controle desde os primeiros dias de vida, em recém-nascido hipotônico. A falta do enzima que catalisa a conversão de glicina em ácido hidroximetiltetra-hidrofólico, dióxido de carbono e amônia, no fígado e no cérebro, resulta em aumento da concentração de glicina no sangue. Neste estudo é relatado caso de hiperglicinemia diagnosticado no período neonatal e caracterizado por hipotonia e múltiplas convulsões não controláveis. Os achados clínicos e eletrencefalográficos, aspectos do tratamento e do estudo anátomo-patológico são comentados

Modelling Destructive Assignments

Abstract. Translating procedural object oriented code into constraints is required for many processes that reason about the execution of this code. The most obvious is for symbolic execution of the code, where the code is executed without necessarily knowing the concrete values. In this paper, we discuss translations from procedural object oriented code to constraints in the context of solving optimisation problems defined via simulation. A key difficulty arising in the translation is the modelling of state changes. We introduce a new technique for modelling destructive assignments that outperforms previous approaches. Our results show that the optimisation models generated by our technique can be as efficient as equivalent hand written models.