24 research outputs found
COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study
Background:
The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms.
Methods:
International, prospective observational study of 60â109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms.
Results:
âTypicalâ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (â€â18 years: 69, 48, 23; 85%), older adults (â„â70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each Pâ<â0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country.
Interpretation:
This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men
Conflict-driven symbolic execution : how to learn to get better
Due to software complexity, manual and automatic testing are not enough to guarantee the correct behavior of software. One alternative to this limitation is known as Symbolic Execution.
Symbolic Execution is a formal verification method that simulates software execution using symbolic values instead of concrete ones. The execution starts with all input variables unconstrained, and assignments that use any input variable are encoded as logical expressions. Whenever a branch is reached, the symbolic execution engine checks which values the branch condition can assume. If more than one valid evaluation is possible, the execution forks, and a new process is created for each possibility.
In cases where the program execution is finite, symbolic execution is complete, and potentially executes every reachable program path. However, the number of paths is exponential in the number of branches in the program, and this approach suffers from a problem know as path explosion.
This thesis presents a novel algorithm that can dynamically reduce the number of paths explored during symbolic execution in order to prove a given set of properties. The algorithm is capable of learning from conflicts detected while symbolically executing a path.
I have named this algorithm Conflict-Driven Symbolic Execution (CDSE), since it was inspired by the conflict-driven clause learning (CDCL) insights introduced by modern boolean satisfiability solvers. The proposed algorithm takes advantage of two features responsible for the success of CDCL solvers: conflict analysis and non-chronological backtracking. In a nutshell, CDSE prunes the search space every time a certain branch is proven infeasible by learning the reason why there is a
conflict.
In order to assess the proposed algorithm, this thesis presents a proof-of-concept CDSE tool named Kite, and compares its performance to the state-of-the-art symbolic execution tool Klee. The results are encouraging, and present practical evidence that conflict-driven symbolic execution can perform better than regular symbolic execution.Science, Faculty ofComputer Science, Department ofGraduat
Formal coâvalidation of lowâlevel hardware/software interfaces
Today's microelectronics industry is increasingly confronted with the challenge of developing and validating software that closely interacts with hardware. These interactions make it difficult to design and validate the hardware and software separately; instead, a verifiable co-design is required that takes them into account. This paper demonstrates a new approach to co-validation of hardware/software interfaces by formal, symbolic co-execution of an executable hardware model combined with the software that interacts with it. We illustrate and evaluate our technique on three realistic benchmarks in which software I/O is subject to hardware-specific protocol rules: a real-time clock, a temperature sensor on an I2C bus, and an Ethernet MAC. We provide experimental results that show our approach is both feasible as a bug-finding technique and scales to handle a significant degree of concurrency in the combined hardware/software model
Psican?lise e sa?de coletiva : aproxima??es e possibilidades de contribui??es.
Este artigo discute possibilidades de
contribui??es da Psican?lise lacaniana para alguns
impasses e dilemas vivenciados no campo de pr?tica
e pesquisa da Sa?de Coletiva. Parte-se do pressuposto
de que as formula??es psicanal?ticas potencializam
transforma??es nas pr?ticas em sa?de relacionadas
? desconstru??o do paradigma biom?dico,
possibilitando uma abordagem mais complexa do
processo sa?de-adoecimento. Para isso, apresentase
aspectos hist?ricos, epistemol?gicos, te?ricos,
metodol?gicos e pol?ticos atrav?s da problematiza??o
dos conceitos de inconsciente, sintoma, diagn?stico,
transfer?ncia, trabalho interdisciplinar, produ??o
do conhecimento e la?o social. A reflex?o pretende
destacar a necessidade de se estimular reflex?es
criativas para al?m da mera prescri??o de condutas,
de forma a se operar em uma ?tica que foge da
imposi??o de normas e valores. Prop?e-se, assim,
um alargamento da compreens?o dos fen?menos, a
identifica??o de novas din?micas e racionalidades,
assim como a constru??o de novas formas de
interven??o
Sobre anorexias e bulimias: concepçÔes e suposiçÔes etiolĂłgicas na perspectiva dos profissionais de SaĂșde
Anorexias e bulimias sĂŁo sĂndromes graves que requerem um manejo cuidadoso. A prĂĄtica clĂnica e a literatura mostram, entretanto, que sua abordagem Ă©, muitas vezes, inadequada. Neste estudo, interessou-nos conhecer o discurso dos profissionais de SaĂșde acerca da caracterização e etiologia desses quadros. Foram realizadas entrevistas semiestruturadas com 13 trabalhadores da rede pĂșblica de saĂșde de um municĂpio de Minas Gerais. A partir dos pontos de convergĂȘncia, divergĂȘncia e silĂȘncio das falas, localizamos eixos discursivos tais como distorção da imagem corporal, estigma e padrĂŁo estĂ©tico do corpo magro veiculado pela mĂdia. Chegamos Ă formação discursiva de todos eles por meio de um diĂĄlogo crĂtico com a literatura mĂ©dica, psicanalĂtica e sociolĂłgica. Os resultados encontrados apontam para a insuficiĂȘncia do saber biomĂ©dico nesse contexto, indicando a necessidade de diĂĄlogos com outras teorias para o alcance de estratĂ©gias mais eficazes de abordagem
Selection of formal verification heuristics for parallel execution
Functional verification is âtheâ major designphase bottleneck for silicon productivity. Since functional verification is an NP-complete problem, it relies on a large number of heuristics with associated parameters (engines). With the advent of parallel processing, formal verification
can be optimized by selecting the best n engines to run in parallel, increasing the chance of reaching successful termination of the verification task. In this paper, we will present a methodology to build engine estimators based on structural metrics and to select n engines to run in parallel. The methodology considers both enginesâ estimated performance and enginesâ correlation. Results confirmed that the methodology can be a very quick selection mechanism for parallelization of engines in order to increase the chance of running the best engines to solve the problem
A type-specific study of human papillomavirus prevalence in cervicovaginal samples in three different Spanish regions
A type-specific study of human papillomavirus prevalence in cervicovaginal samples in three different Spanish regions. APMIS 2009; 117:22-7. Human papillomavirus (HPV) is the most frequent sexually transmitted viral infection. It is necessary to know HPV genotype distribution to identify how many women will be protected by HPV vaccines. During a period of 18 months, we have analyzed 2362 HPV positive reporting data from a secondary demand screening program in three regions in Spain (Cantabria, Leon and Burgos). The study has been conducted using polymerase chain reaction and tube array hybridization covering the 35 HPV genotypes described as affecting anogenital mucosa. There were no significant differences between the three regions according to genotype distribution. The most frequent were HPV16 (19.18%), HPV53 (11.26%) and HPV58 (7.66%). HPV18 was the source of 4.02% of infections. High-risk HPVs were found in 1863/2362 cases. HPV16 was present in 24.3% of high-risk infections and HPV18 was found in 5.1%. Uncommon genotypes (o5% of the total prevalence each) were found in 17,9% of the total high-risk infections (334/1863). Multiple infections were diagnosed in 22% of the cases. The HPV genotype distribution is different from previously published data when multiple types are included in the screening. Both HPV16/18 account for 30% of high-risk infections in a clinical setting in Spain. The presence of multiple genotypes is very common among the population