215 research outputs found

    Air temperature changes in Toruń (central Poland) from 1871 to 2010

    Get PDF
    The article presents a detailed analysis of changes in air temperature in Toruń in the period 1871–2010 on the basis of homogenised monthly, seasonal and annual air temperature series which have been newly constructed (i.e. extended by the 50 years of 1871–1920). Over the 140-year study period, a sizeable and statistically significant increase of 0.1 °C per decade was found in the air temperature in Toruń. The greatest increases occurred for spring and winter, at 0.12 and 0.11 °C, respectively. A lesser warming, meanwhile, was recorded for autumn (0.10 °C/10 years), and particularly for summer (0.07 °C/10 years). The air temperature trends are statistically significant for all seasons. Air temperature differences between the monthly averages of three analysed subperiods (1871–1900, 1901–1950 and 1951–2010) and averages for the entire period under review rarely exceeded ± 0.5 °C. In all of these periods, the highest average air temperatures occurred in July and the lowest in January. The period of 1981–2010 had the highest frequency of occurrence of very and extremely warm seasons and years. Meanwhile, the highest frequency of very and extremely cool seasons and years was recorded in the 1940s and in the nineteenth century. In the period of 1871–2010, winters shortened markedly (by 7%) and summers lengthened by 3.8%. All of the presented aspects of air temperature in Toruń, which is representative of the climate of central Poland, are in close agreement with the findings of analogous studies of the same for other areas of Poland and Central Europe

    Health and safety issues in the Victorian workplace: an example of mandibular phosphorus necrosis from Gloucester, UK

    Get PDF
    Working conditions in factories during the Industrial Era in Great Britain have been linked to numerous occupational diseases. In this paper, the authors present a case study from Victorian Gloucester, where skeletal remains of a young male recovered from the Southgate Street 3/89 excavation exhibit osteonecrosis on the left mandibular ramus, a condition known as “phossy jaw”. The case is examined in terms of macroscopic characteristics, distribution and severity of lesions and differential diagnosis. The lesions consist of extensive bone necrosis with periosteal reaction and subperiosteal new bone formation that affects the left side of the mandible. Conditions that may have produced similar changes were considered and include various forms of neoplasms, actinomycosis and taphonomic alterations. However, these are rejected as they are not supported by the lesion characteristics. Additional supportive evidence for the case of phosphorus necrosis is offered by the historical context: in the 19th century, Gloucester was one of the main centres for match manufacture and it is well known that individuals who were directly exposed to phosphorus fumes developed a condition known as “phossy jaw”. The potential contribution of the current analysis in our understanding of working conditions in Victorian Gloucester is evaluated

    Physically Similar Systems - A History of the Concept

    Get PDF
    PreprintThe concept of similar systems arose in physics, and appears to have originated with Newton in the seventeenth century. This chapter provides a critical history of the concept of physically similar systems, the twentieth century concept into which it developed. The concept was used in the nineteenth century in various fields of engineering (Froude, Bertrand, Reech), theoretical physics (van der Waals, Onnes, Lorentz, Maxwell, Boltzmann) and theoretical and experimental hydrodynamics (Stokes, Helmholtz, Reynolds, Prandtl, Rayleigh). In 1914, it was articulated in terms of ideas developed in the eighteenth century and used in nineteenth century mathematics and mechanics: equations, functions and dimensional analysis. The terminology physically similar systems was proposed for this new characterization of similar systems by the physicist Edgar Buckingham. Related work by Vaschy, Bertrand, and Riabouchinsky had appeared by then. The concept is very powerful in studying physical phenomena both theoretically and experimentally. As it is not currently part of the core curricula of STEM disciplines or philosophy of science, it is not as well known as it ought to be

    Insights into household transmission of SARS-CoV-2 from a population-based serological survey

    Get PDF
    Understanding the risk of infection from household- and community-exposures and the transmissibility of asymptomatic infections is critical to SARS-CoV-2 control. Limited previous evidence is based primarily on virologic testing, which disproportionately misses mild and asymptomatic infections. Serologic measures are more likely to capture all previously infected individuals. We apply household transmission models to data from a cross-sectional, household-based population serosurvey of 4,534 people ≥5 years from 2,267 households enrolled April-June 2020 in Geneva, Switzerland. We found that the risk of infection from exposure to a single infected household member aged ≥5 years (17.3%,13.7-21.7) was more than three-times that of extra-household exposures over the first pandemic wave (5.1%,4.5-5.8). Young children had a lower risk of infection from household members. Working-age adults had the highest extra-household infection risk. Seropositive asymptomatic household members had 69.4% lower odds (95%CrI,31.8-88.8%) of infecting another household member compared to those reporting symptoms, accounting for 14.5% (95%CrI, 7.2-22.7%) of all household infections

    Volumetric Properties of the Mixture 2-Methylpropenoic acid C4H6O2 + C7H8 Toluene (LB0111, VMSD1111)

    No full text

    Propan-1-ol C3H8O + C6H14O Diisopropyl ether

    No full text

    Methyl 2-methylpropenoate C5H8O2 + C7H8 Toluene

    No full text

    Methyl ethanoate C3H6O2 + C6H12 Hex-1-ene

    No full text
    corecore