Counterexample-Guided Polynomial Loop Invariant Generation by Lagrange Interpolation

We apply multivariate Lagrange interpolation to synthesize polynomial quantitative loop invariants for probabilistic programs. We reduce the computation of an quantitative loop invariant to solving constraints over program variables and unknown coefficients. Lagrange interpolation allows us to find constraints with less unknown coefficients. Counterexample-guided refinement furthermore generates linear constraints that pinpoint the desired quantitative invariants. We evaluate our technique by several case studies with polynomial quantitative loop invariants in the experiments

Thalidomide-induced sensory polyneuropathy and electrophysiological study of the sural nerve as a screening diagnosis: a case report

Polineuropatia é uma condição clínica freqüente com sintomatologia debilitante e o tratamento depende fundamentalmente da etiologia. Inúmeras são as causas possíveis deste tipo de distúrbio e o diagnóstico etiológico nem sempre é fácil. Neste relato de caso descrevemos um caso de um paciente com mieloma múltiplo que evoluiu com polineuropatia puramente sensitiva, comprovada por estudo eletrofisiológico, induzida por talidomida.Polyneuropathy is a common clinical condition with debilitating symptoms whose treatment depends on etiology. There are numerous possible causes of this type of disorder and the etiological diagnosis is not always easy. In this case report we describe a case of a patient with multiple myeloma who developed purely sensory polyneuropathy, confirmed by electrophysiological study, induced by thalidomide

Prevalence of Carpal Tunnel syndrome in wheel-chair users due to medullary lesion

Medullary lesions create numerous functional limitations directly related to the loss of nervous functions. However, the mechanics associated with the use of a wheelchair impose a load on the upper limbs that seems to be linked to secondary lesions in the tendinous and nervous structures. Objective: This study seeks to evaluate the appearance of signs of electromyographic impairments of the median nerve around the carpal tunnel in individuals who use wheelchairs due to medullary lesion. Method: Following a transversal design, all the individuals with medullary lesion in the rehabilitation program at the HC-FMUSP Institute of Physical Medicine and Rehabilitation in the year 2010 were submitted to a study of nervous conduction and electromyography. Those findings were correlated with biodemographic and clinical variables, as well as to characteristics of the use of wheelchairs. Results: Twenty-eight (28) individuals were evaluated, with an average age of 41.4 years (60.7% males). Most patients moved the wheelchair for less than four hours and would move it less than 500 meters a day. An absence of painful symptoms was found in 67.9%, while only 7.1% presenting positive Phalen and/or Tinel test. Half of the sample presented the neurophysiological diagnostic of carpal tunnel syndrome (CTS), which had a statistically significant association with age (p = 0.024), but not with the time and distance moving the wheelchair daily, the use of protection or adaptation of the wheelchair, of pain in upper limbs, or the presence of positive signs of CTS in the physical exam. Conclusion: We concluded that the electromyographic signs of CTS are very prevalent in these individuals, which suggests more situations of risk for the integrity of their upper limbs and demands the development of a more efficient biomechanical strategy for prevention.A lesão medular acarreta inúmeras limitações funcionais diretamente relacionadas à perda das funções nervosas. Todavia, a mecânica associada ao uso de cadeiras de rodas impõe uma sobrecarga aos membros superiores que parece estar associada ao aparecimento de lesões secundárias em estruturas tendíneas e nervosas. Objetivo: Avaliar o surgimento de sinais eletromiográficos de comprometimento do nervo mediano na altura do túnel do carpo em indivíduos usuários de cadeiras de rodas devido à lesão medular. Método: Seguindo um desenho transversal, todos os indivíduos com lesão medular sob programa de reabilitação no Instituto de Medicina Física e Reabilitação do HC-FMUSP no ano 2010 foram submetidos a estudo de condução nervosa e eletromiografia. Esses achados foram correlacionados com variáveis biodemográficas e clínicas, bem como características do uso de cadeiras de rodas. Resultados: Foram avaliados 28 indivíduos, com média de idade de 41,4 anos (60,7% homens). A maioria dos pacientes tocava a cadeira de rodas por um tempo inferior a quatro horas e percorria uma distância tocando a cadeira de rodas inferior a 500 metros por dia. A ausência de sintomas dolorosos ocorreu em 67,9%, enquanto apenas 7,1% apresentavam o teste de Phalen e/ou Tinel positivos. Metade da amostra apresentava o diagnóstico neurofisiológico de síndrome do túnel do carpo (STC), que apresentou associação estatisticamente significante com a idade (p = 0,024), mas não com tempo e distância percorrida tocando a cadeira de rodas diariamente, uso de proteção ou adaptação na cadeira de rodas, sintomatologia dolorosa em membros superiores ou presença de sinais positivos para STC ao exame físico. Conclusão: Os sinais eletromiográficos de STC são muito prevalentes nesses indivíduos, o que sugere maiores situações de risco para a integridade dos membros superiores e exige o desenvolvimento de estratégias biomecanicamente mais eficazes para a prevenção

Ganglionopatia como manifestação inicial de neoplasia pulmonar: relato de caso

Ganglionopathy is a rare condition defined by an injury to the sensory neurons in the dorsal root ganglion. This disease belongs to a group of peripheral polyneuropathies with an exclusively sensory and axonal pattern and its diagnoses can be made by an electromyoneurographic study. The association between ganglionopathy and other underlying pathologies, such as some types of cancer, autoimmune diseases, and celiac disease is often mentioned in published studies. The purpose of this report was to describe the case of a patient suffering from ganglionopathy including a detailed discussion of the electromyoneurographic study that led the attending physician to a diagnosis of neoplastic lung disease. The conclusion therefore was that it is important for the neurophysiology specialist to keep in mind the possible causes of ganglionopathy and, through this diagnosis, to help the attending physician in making an early and full workup of the patient.A ganglionopatia é uma entidade rara que consiste na afecção dos neurônios sensitivos da raiz dorsal, fazendo parte do grupo das polineuropatias periféricas do tipo exclusivamente sensitivo com comprometimento axonal e tendo seu diagnóstico feito através de estudo eletroneuromiográfico. A associação entre a ganglionopatia e outras patologias como neoplasias, doenças autoimunes, doença celíaca, entre outras é amplamente citada na literatura. O objetivo deste trabalho é descrever o caso clínico de um paciente com diagnóstico de neoplasia pulmonar cuja manifestação inicial foi a ganglionopatia, incluindo a descrição detalhada do exame eletroneuromiográfico que auxiliou no processo diagnóstico do médico assistente. Concluímos ser importante que o médico neurofisiologista tenha em mente as possíveis causas da ganglionopatia e saiba apontar o médico assistente para que a investigação possa ser realizada de maneira completa e precoce

Removing Algebraic Data Types from Constrained Horn Clauses Using Difference Predicates

We address the problem of proving the satisfiability of Constrained Horn Clauses (CHCs) with Algebraic Data Types (ADTs), such as lists and trees. We propose a new technique for transforming CHCs with ADTs into CHCs where predicates are defined over basic types, such as integers and booleans, only. Thus, our technique avoids the explicit use of inductive proof rules during satisfiability proofs. The main extension over previous techniques for ADT removal is a new transformation rule, called differential replacement, which allows us to introduce auxiliary predicates corresponding to the lemmas that are often needed when making inductive proofs. We present an algorithm that uses the new rule, together with the traditional folding/unfolding transformation rules, for the automatic removal of ADTs. We prove that if the set of the transformed clauses is satisfiable, then so is the set of the original clauses. By an experimental evaluation, we show that the use of the differential replacement rule significantly improves the effectiveness of ADT removal, and we show that our transformation-based approach is competitive with respect to a well-established technique that extends the CVC4 solver with induction.Comment: 10th International Joint Conference on Automated Reasoning (IJCAR 2020) - version with appendix; added DOI of the final authenticated Springer publication; minor correction

The use of zootherapeutics in folk veterinary medicine in the district of Cubati, Paraíba State, Brazil

<p>Abstract</p> <p>Background</p> <p>The present work addresses the use of zootherapy in folk veterinary medicine (ethnoveterinary) by the residents of the municipal district of Cubati, microregion of Seridó, Paraíba State, Brazil. It sought to identify the principal animals used as medicinal sources for zootherapeutics and to contribute to the preservation and sustainability of this traditional knowledge.</p> <p>Methods</p> <p>Field research was undertaken on a weekly or biweekly basis during the period November, 2006, to January, 2007. Free, semi-structured, and open interviews were made with local residents of the municipal district of Cubati (in both urban and rural settings) as well as with venders in public markets. A total of 25 individuals of both sexes were interviewed (with ages varying from 26 to 78 years) although only 16 were finally chosen as informants as these people demonstrated the greatest degree of knowledge concerning zootherapeutics. Graphs and percentages were generated using Microsoft^©Excel 2007 software, and the species were identified by photographic registration and subsequent bibliographical surveys.</p> <p>Results</p> <p>Mammals constitute the main medicinal zootherapeutic source for folk veterinary medicines in the studied area, both in terms of the total number of species used and the frequency of their citation. Sheep (<it>Ovis aries</it>), pigs (<it>Sus scrofa</it>), cattle (<it>Bos taurus</it>), and foxes (<it>Cerdocyon thous</it>) were mentioned by 62.5, 43.75, 37.5, and 31.25% of the informants, respectively, as being used in folk veterinary medicine. Additionally, chameleons (<it>Iguana iguana</it>), chickens (<it>Gallus domesticus</it>), and rattlesnakes (<it>Crotalus durissus</it>) were mentioned by 75, 43.75, and 31.25% of the informants, respectively. Relatively simple animal illnesses, such as furuncles, or injuries resulting from embedded thorns or skin eruptions are responsible for the largest number of zootherapeutic treatment, while, diseases of greater complexity, such as rabies and brucellosis, were not even mentioned. Fat from various animals constituted the most frequently cited resource used for its medicinal-veterinary properties.</p> <p>Conclusion</p> <p>The examination of folk knowledge and health practices allows a better understanding of human interactions with their local environment, and aids in the formulation of appropriate strategies for natural resource conservation.</p

Friends with benefits: implementing corecursion in foundational proof assistants

We introduce AmiCo, a tool that extends a proof assistant, Isabelle/HOL, with flexible function definitions well beyond primitive corecursion. All definitions are certified by the assistant’s inference kernel to guard against inconsistencies. A central notion is that of friends: functions that preserve the productivity of their arguments and that are allowed in corecursive call contexts. As new friends are registered, corecursion benefits by becoming more expressive. We describe this process and its implementation, from the user’s specification to the synthesis of a higher-order definition to the registration of a friend. We show some substantial case studies where our approach makes a difference