Context-sensitive autoassociative memories as expert systems in medical diagnosis

BACKGROUND: The complexity of our contemporary medical practice has impelled the development of different decision-support aids based on artificial intelligence and neural networks. Distributed associative memories are neural network models that fit perfectly well to the vision of cognition emerging from current neurosciences. METHODS: We present the context-dependent autoassociative memory model. The sets of diseases and symptoms are mapped onto a pair of basis of orthogonal vectors. A matrix memory stores the associations between the signs and symptoms, and their corresponding diseases. A minimal numerical example is presented to show how to instruct the memory and how the system works. In order to provide a quick appreciation of the validity of the model and its potential clinical relevance we implemented an application with real data. A memory was trained with published data of neonates with suspected late-onset sepsis in a neonatal intensive care unit (NICU). A set of personal clinical observations was used as a test set to evaluate the capacity of the model to discriminate between septic and non-septic neonates on the basis of clinical and laboratory findings. RESULTS: We show here that matrix memory models with associations modulated by context can perform automatic medical diagnosis. The sequential availability of new information over time makes the system progress in a narrowing process that reduces the range of diagnostic possibilities. At each step the system provides a probabilistic map of the different possible diagnoses to that moment. The system can incorporate the clinical experience, building in that way a representative database of historical data that captures geo-demographical differences between patient populations. The trained model succeeds in diagnosing late-onset sepsis within the test set of infants in the NICU: sensitivity 100%; specificity 80%; percentage of true positives 91%; percentage of true negatives 100%; accuracy (true positives plus true negatives over the totality of patients) 93,3%; and Cohen's kappa index 0,84. CONCLUSION: Context-dependent associative memories can operate as medical expert systems. The model is presented in a simple and tutorial way to encourage straightforward implementations by medical groups. An application with real data, presented as a primary evaluation of the validity and potentiality of the model in medical diagnosis, shows that the model is a highly promising alternative in the development of accuracy diagnostic tools

Phylogenentic and enzymatic characterization of psychrophilic and psychrotolerant marine bacteria belong to γ-Proteobacteria group isolated from the sub-Antarctic Beagle Channel, Argentina

The phylogenetic and physiological characteristics of cultivable-dependent approaches were determined to establish the diversity of marine bacteria associated with the intestines of benthonic organisms and seawater samples from the Argentine´s Beagle Channel. A total of 737 isolates were classified as psychrophlic and psychrotolerant culturable marine bacteria. These cold-adapted microorganisms are capable of producing cold-active glycosyl hydrolases, such as β-glucosidases, celulases, β-galactosidases, xylanases, chitinases and proteases. These enzymes could have potential biotechnological applications for use in low-temperature manufacturing processesAccording to polymerase chain reaction-restriction fragment length polymorphism analysis of part of genes encoding 16S ribosomal DNA (ARDRA) and DNA gyrase subunit B (gyrB-RFLP), 11 operational taxonomic units (OTU) were identified and clustered in known genera using InfoStat software. The 50 isolates selected were sequencing based on near full sequence analysis of 16S rDNA and gyrB sequences and identified by their nearest neighbors ranging between 96 and 99 % of identities. Phylogenetic analyses using both genes allowed relationships between members of the cultured marine bacteria belonging to the γ-Proteobacteria group (Aeromonas, Halteromonas, Pseudomonas, Pseudoalteromonas, Shewanella, Serratia, Colwellia, Glacielocola and Psychrobacter) to be evaluated. Our research reveals a high diversity of hydrolytic bacteria and their products actuality has an industrial use in several bioprocesses at low-temperature manufacturing.Fil: Cristobal, Hector Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Investigación para la Industria Química (i); ArgentinaFil: Benito, Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); ArgentinaFil: Lovrich, Gustavo Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Abate, Carlos Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentin

Urban mobility and transportation

Urban areas are developing quickly, innovative technologies grant enlarged scope for mobility management. According to literature, 50% of world population and as much as 75% of EU population live in cities, where the majority of GDP is generated. CO2 is responsible of 75% GHG worldwide and transportation is worth around 20% of this share and the contribution is rising, in particular in urban areas. Besides pollution and noise, also collisions (70% of which in urban areas) and congestion - which is worth around 1% of EU GDP in terms of time lost due to delay suffered - are negative externalities. Finally, due to urban sprawl induced by car-centric cultural regimen under the justification of cheaper land costs, the need to travel has been growing notwithstanding economic downturns, resulting in an increased threat of social exclusion for those who cannot afford a car. The attitude towards urban transportation has shifted from laissez-faire to deep concern: as far as EU is concerned, the Action plan on Urban Mobility (2009) recommended the adoption of Sustainable Urban Mobility Plans (SUMPs), the 2011 White Paper envisaged SUMPs to become mandatory for cities over 100,000 inhabitants and a base requisite to access to EU Funds. The 2013 Guidelines and the 2015 EC Urban Mobility Package have further established the SUMP policy. In 2015, UN adopted the “Agenda for sustainable development 2030” (7 out of 17 objectives deal with transportation) and a new worldwide agreement on climate has been signed in Paris. Finally, the funding foreseen by EU research project H2020 (8,2% of the total budget allocated on transportation) will further encourage the investigation of new strategies and technologies. SUMPs emphasize long term vision, the active involvement of citizen and stakeholders (Priester et al., 2014), the setting of targets, measures and a radical reform of regulatory and funding framework to avoid start-and-stop approach (Hickman et al., 2013; Stephenson et al., 2018). Nevertheless, the commitment level is different: developing countries would rather urge to build more and modern infrastructures, leaving the environment as a secondary priority. SUMPs are expected to find solution to road congestion and policy fragmentation between documents (Baidan, 2016). According to EU CIVITAS project’s outcomes, the implementation of SUMPs can be hindered by pro-car & infrastructure building lobbyism, inefficient planning - monitoring – dissemination, lack of stakeholder involvement and support, excessive outsourcing, fluctuation of political commitment over time (Ibeas et al., 2011; Persia et al., 2016), inadequate coordination among policy tiers and plans (Stephenson et al., 2018), unsupportive or inappropriate regulation and financial structures, poor or missing data and reliance to business-as-usual scenarios. The topics facing less acceptance have been accessibility, logistic, traffic control, cycling and walking measures (Bruhova Foltynova & Jordova, 2014)

Influence of Hyperoxia and Mechanical Ventilation in Lung Inflammation and Diaphragm Function in Aged Versus Adult Rats

Although assist ventilation with FIO2 0.21 is the preferable mode of ventilation in the intensive care unit, sometimes controlled ventilation with hyperoxia is needed. But the impact of this setting has not been extensively studied in elderly subjects. We hypothesized that a high fraction of inspired oxygen (FiO(2)) and controlled mechanical ventilation (CMV) is associated with greater deleterious effects in old compared to adult subjects. Adult and old rats were submitted to CMV with low tidal volume (6 ml/kg) and FiO(2) 1 during 3 or 6 h. Arterial blood gas samples were measured at 0, 60 and 180 min (four groups: old and adult rats, 3 or 6 h of CMV), and additionally at 360 min (two groups: old and adult rats, 6 h of CMV). Furthermore, total protein content (TPC) and tumor necrosis factor-alpha (TNF-alpha) in bronchoalveolar lavage were assessed; lung tissue was used for malondialdehyde and histological analyses, and the diaphragm for measurement of contractile function. Arterial blood gas analysis showed an initial (60 min) greater PaO2 in elderly versus adult animals; after that time, elderly animals had lowers pH and PaO2, and greater PaCO2. After 3 h of CMV, TPC and TNF-alpha levels were higher in the old compared with the adult group (P < 0.05). After 6 h of MV, malondialdehyde was significantly higher in elderly compared with the adult animals (P < 0.05). Histological analysis showed leukocyte infiltration and edema, greater in old animals. in diaphragm, twitch contraction with caffeine significantly declined after 6 h of CMV only for the elderly group. These data support the hypothesis that relatively short-term CMV with low tidal volume and hyperoxia has greatest impact in elderly rats, decreasing diaphragmatic contractile function and increasing lung inflammation.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Ctr Estudo Diagnost & Invest Hipertermia Maligna, Disciplina Anestesiol Dor & Terapia Intens, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Ctr Estudo Diagnost & Invest Hipertermia Maligna, Disciplina Anestesiol Dor & Terapia Intens, BR-04024002 São Paulo, BrazilFAPESP: FAPESP: 06/60834-9FAPESP: 08/51508-6Web of Scienc