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Se presenta un recuento del surgir de la Escuela Matemática de Varsovia, en el periodo Entreguerras (1918-1939), la cual pasó de ser periferia a ser centro de investigación matemática de punta en teoría de conjuntos y ramas cercanas. También se añade puntos para la discusión de la idea de especializar la Escuela en teoría de conjuntos a través de Fundamenta Mathematicae.

The increasing production of municipal solid waste (MSW) and its improper disposal affect environmental issues. As a way of dealing with landfill overload and still encompassing the growing demand for energy in cities, new technologies called Waste-to-Energy (WtE) are gaining more attention. Therefore, urban woody residues and MSW have become attractive as sustainable energy sources due to their availability and disponibility. In this context, the present work aims to perform the energy analysis of a hybrid biofuel formed by MSW and lignocellulosic residues in Brasilia, Brazil’s capital. For the study, a synthetic MSW was produced based on the main components of the landfill, which are paper and cardboard, plastic, and organic residues. The lignocellulosic blend was established based on six wood species representing the city’s pruning residues. To obtain a quality fuel, the individual components of the biomass, as well as its blend, were subjected to torrefaction pre-treatment (275 °C for 60 min with a heating rate of 5 °C.min-1), aiming to improve its characteristics such as moisture content, fixed carbon, and higher heating value (HHV). The hybrid blend was determined following the proportions, 80/20% and 70/30% (biomass/MSW). The torrefied products were characterized by proximate, ultimate, and calorific analysis. The obtained biofuel properties were used in thermodynamic equilibrium modeling to investigate the effect of the hybrid blends composition and gasification operational conditions on the producer gas quality. Three atmospheres (air, S/B = 0.25, S/B = 0.5) and a temperature range of 600–1000 °C were employed. A multi-criteria analysis decision evaluated the producer gas composition, lower heating value (LHV), and cold gas efficiency (CGE) for various gasification conditions. The results obtained show that: i) the torrefied lignocellulosic blend at 275 °C exhibited greater higher heating value (HHV) and lower H/C and O/C among the lignocellulosic samples; ii) the hybrid blend showed an intermediate HHV between the synthetic MSW and the lignocellulosic blend, and the hybrid; iii) the torrefied samples exhibit greater LHV and CGE during gasification; iv) H2 production was more advantageous with the raw feedstocks and steam atmosphere during gasification; iv) The producer gas obtained with air gasification of the torrefied blends evidenced best properties for direct combustion or green hydrogen production., Proceedings of the 30th European Biomass Conference and Exhibition, 9-12 May 2022, Online, pp. 205-213

Objective: To describe the environmental practices of participants in an urban organic community garden at the beginning of their gardening experience and after a period of six months, and to discover their opinion about how this activity influenced the consumption of vegetables, fruits and organic food. Method: Interviews using structured questionnaires were conducted twice with 115 city dwellers: when they started in the vegetable garden and about 6 months later. The questionnaire included questions related to environmental practices. The second evaluation also included questions related to the consumption of organic food, vegetables and fruit. Results: This research showed significant behavioural transformation, including positive outcomes in environmental practices such as recycling and trying to persuade friends or family to recycle, compost leftovers or choose to walk/bike to save petrol. In the opinion of the participants, activities in the organic community garden helped to increase consumption of fruits, vegetables and organic food. Conclusion: The study results reinforce the hypothesis that an organic community vegetable garden can induce significant, positive behavioural changes among its users. In particular this research suggests horticulture is associated with positive improvements in personal environmental behaviours, awareness of the environment's high social priority and increased consumption of organic food, fruit and vegetables.

Microorganisms have shown their ability to colonize extreme environments including deep subsurface petroleum reservoirs. Physicochemical parameters may vary greatly among petroleum reservoirs worldwide and so do the microbial communities inhabiting these different environments. The present work aimed at the characterization of the microbiota in biodegraded and non-degraded petroleum samples from three Brazilian reservoirs and the comparison of microbial community diversity across oil reservoirs at local and global scales using 16S rRNA clone libraries. The analysis of 620 16S rRNA bacterial and archaeal sequences obtained from Brazilian oil samples revealed 42 bacterial OTUs and 21 archaeal OTUs. The bacterial community from the degraded oil was more diverse than the non-degraded samples. Non-degraded oil samples were overwhelmingly dominated by gammaproteobacterial sequences with a predominance of the genera Marinobacter and Marinobacterium. Comparisons of microbial diversity among oil reservoirs worldwide suggested an apparent correlation of prokaryotic communities with reservoir temperature and depth and no influence of geographic distance among reservoirs. The detailed analysis of the phylogenetic diversity across reservoirs allowed us to define a core microbiome encompassing three bacterial classes (Gammaproteobacteria, Clostridia, and Bacteroidia) and one archaeal class (Methanomicrobia) ubiquitous in petroleum reservoirs and presumably owning the abilities to sustain life in these environments.

International audience; The European community cannot address the issue of bio-waste solely in terms of collection and waste management, as such activities generate costs. Today, waste prevention in Europe must involve waste reduction and prevention at a local level, targeting all producers of bio-waste, not only consumers and households, and promoting the use of a number of waste reduction practices including composting, mulching, grinding, use of slow-growing plant species, using bio-waste as animal feed, reducing food wastage and the use of ramial wood chips. The Miniwaste project, supported by the European Life+ program (2010-2012), aims to provide evidence that it is possible to significantly reduce the production of bio-waste generated in the European Union, as well as provide tools and points of further reflection on bio-waste prevention. The partnership (Rennes Métropole, Irstea, City of Brno, LIPOR in Porto, and ACR+) wishes to set up a computerised tool for local authorities within Europe. This project will help users to conduct a bio-waste management programme including territorial diagnosis, the implementation and monitoring of specific preventive actions and the evaluation of these actions. The overall structure will be based on three different modules: 1-A decision making assistance module that includes a territorial diagnosis chart offering several scenarios associated with different potential possible actions in the field of bio-waste prevention: Composting (home, community, apartment blocks, vermi-composting, catering services), food waste (household,restaurant), smart gardening and animal feeding. The territorial diagnosis is produced on the scale chosen by the user in order to get homogeneous data. It could be a neighbourhood, district, town, etc. For a given sector, the decision making module consists in entering data of 15 territorial indicators in terms of population, current waste management and current preventive actions on the territory, etc. Meanwhile, a calculation of potential waste reduction is processed by the computer using an algorithm. The result of the diagnosis is displayed for the whole territory and for each sector according to the list defined. Corresponding to the results, synthetic worksheets are proposed as a real decision making tool with the following information: target, type of waste concerned, linked indicators, main actions, participants involved, materials necessary, personnel necessary, an estimate of cost, and expected results. With such information (diagnosis and worksheets), the users are able to choose one or several preventive actions to implement in their territory. 2-Some guidelines to implement the actions and especially some data sheets proposing activity indicators and impact indicators: depending on the preventive actions chosen, the user can download the corresponding procedural sheet which explains step by step how to implement the actions in detail. Moreover, a data sheet is available with a list of relevant indicators (awareness, number of composters, etc.) 3-A results display module, producing graphs to help visualise the results. This web tool will be available on the Miniwaste website by subscription, from 2013 (www.miniwaste.eu). More information will be provided and a tool demonstration will be organized during the final conference scheduled in Rennes in November 2012.

Los síndromes de malabsorción constituyen una entidad compleja de etiopatogenia multifactorial. Clásicamente se describe el sprue tropical, entidad con predisposición genética…

The endovascular treatment (ET) of traumatic rupture of the thoracic aorta (TRTA) may represent, particularly in patients with severe multisystemic post-traumatic surgical lesions, an alternative approach to traditional surgery. We observed (October 2001- November 2004) 5 male patients (age: range 23-42 years - average 32,4) affected by TRTA (3 isthmic aortic ruptures - 2 distal descending thoracic aorta ruptures), all successfully treated with an endovascular approach. The Glasgow Coma Score (GCS) ranged between 5 and 13. After performing resuscitation manoeuvres, all patients were investigated with total body CT scans in order to evaluate the thoracic aorta and to identify associated visceral lesions. In 4 cases were evident associated visceral lesions (3 cases: bone, abdominal and neurosurgical trauma - 1 case: bone, abdominal, neurosurgical and thoracic trauma). All the procedures were performed in the operative room using DSA (Digital Subtraction Angiography). The mean operating time was 105 minutes (range 80 - 125). We didn't observed early and late complications (follow-up: average 24 months, range 12-36). In conclusion the ET of TRTA represents in 'critical' patients with severe polytrauma an alternative approach to traditional surgery in order to 'stabilizing' the cardiovascular clinical parameters and to treating 'safety' the other associated surgical lesions.

El principal limitante fitosanitario del cultivo de lechuga (Lactuca sativa L.) es la enfermedad conocida como moho blanco causada por el hongo Sclerotinia sclerotiorum (Lib.) de Bary. Con el fin de realizar un aporte al conocimiento de esta enfermedad y establecer protocolos para su control en campo se realizó un experimento entre los meses de febrero y mayo de 2006 en el cual se compararon tres métodos de control: aplicación de 0,5 kg· ha-1 de procimidona, dosis de conidiosporas (Trichoderma harzianum DSM 14944) de 0,25 g· m-2 de suelo, solarización, integración de solarización con procimidona y solarización con T. harzianum. Se evaluó la incidencia de la enfermedad, densidad de inóculo en el suelo antes y al finalizar el ensayo, temperatura del suelo durante la solarización y productividad. La densidad promedio del inóculo fue de 1,67 esclerocios de S. sclerotiorum por100 g de suelo al inicio y 2,07 esclerocios por 100 g de suelo al finalizar el ensayo. La temperatura del suelo solarizado se incrementó hasta 50°C con un promedio de 34,69°C hacia el medio día. Los porcentajes de incidencia de la enfermedad fueron: con procimidona, 3,3 por ciento, con T. harzianum, 10,0 por ciento, con solarización, 15,8 por ciento, con solarización y procimidona, 8,8 por ciento, con solarización y T. harzianum, 9,2 por ciento y testigo 18,3 por ciento. No se presentaron diferencias significativas en la productividad. En conclusión el control de la enfermedad fue mejor con la aplicación de procimidona y deficiente con T. harzianum y la solarización Lechuga-Lechugas - Lactuca sativa