1,098 research outputs found

    An Ultrastructural and Histological Study of the Equine Respiratory Tract in Health and Disease, Volume I

    Get PDF
    There were two main aims in the work presented in this thesis. First, to carry out a detailed scanning electron microscopic (SEM), histological and, where appropriate, transmission electron microscopic (TEM) study of the surface features of the entire respiratory tract of normal horses. The second aim was to investigate the effects of respiratory disease (Streptococcus equi infection or Strangles and chronic obstructive pulmonary disease) on equine respiratory tract surfaces

    The effect of short-term kaempferol exposure on reactive oxygen levels and integrity of human (HL-60) leukaemic cells

    Get PDF
    AbstractFlavonoids may be a principal contributor to the cancer preventative activity of fruit- and vegetable-rich diets and there is interest in their use as dietary supplements. However, there is potential conflict between the cytoprotective and cytotoxic activities of flavonoids, and their efficacy as anti-cancer agents is unresolved. Here, the integrity and survival of HL-60 promyelocytic leukaemia cells following short-term (90 min) exposure to the dietary abundant flavonoid kaempferol (1–100 μM) is reported. Supplementation initially decreased reactive oxygen levels but, paradoxically, a dose-dependent increase in single-strand DNA breakage occurred. However, there was no increase in oxidised DNA purines or membrane damage. Following a 24-h recovery period in non-kaempferol supplemented media, DNA single-strand breakage had declined and kaempferol exposed and control cultures possessed similar reactive oxygen levels. A reduction in 3H-thymidine incorporation occurred with ≥10 μM kaempferol. One hundred micromolar kaempefrol increased the proportion of cells in G2-M phase, the proportion of cells with a sub-G1 DNA content and enhanced ‘active’ caspase-3 expression but only induced a loss of mitochondrial membrane potential within a minority of cells. The relevance of induced DNA damage within a non-overtly oxidatively stressed environment to the disease preventative and therapeutic use of kaempferol is discussed

    Consistency between ARPES and STM measurements on SmB6_6

    Full text link
    Strongly correlated topological surface states are promising platforms for next-generation quantum applications, but they remain elusive in real materials. The correlated Kondo insulator SmB6_6 is one of the most promising candidates, with theoretically predicted heavy Dirac surface states supported by transport and scanning tunneling microscopy (STM) experiments. However, a puzzling discrepancy appears between STM and angle-resolved photoemission (ARPES) experiments on SmB6_6. Although ARPES detects spin-textured surface states, their velocity is an order of magnitude higher than expected, while the Dirac point -- the hallmark of any topological system -- can only be inferred deep within the bulk valence band. A significant challenge is that SmB6_6 lacks a natural cleavage plane, resulting in ordered surface domains limited to 10s of nanometers. Here we use STM to show that surface band bending can shift energy features by 10s of meV between domains. Starting from our STM spectra, we simulate the full spectral function as an average over multiple domains with different surface potentials. Our simulation shows excellent agreement with ARPES data, and thus resolves the apparent discrepancy between large-area measurements that average over multiple band-shifted domains and atomically-resolved measurements within a single domain

    The impacts of the trade liberalization of environmental goods on power system and CO2 emissions

    Get PDF
    The trade liberalization of Environmental Goods (EG), through as Environmental Goods Agreement (EGA), is crucial in low carbon electricity technology diffusion. However, there is a big gap of the EG definition lists and the integrated effectiveness analysis of EGA. This paper analyses the effects of the trade liberalization of EG based on macroeconomic and electricity sector models and attempts to find a more efficient EG trade policy by comparing different EG lists, considering end-use control and combining the EG policy with a carbon tax. The results show that the trade liberalization of EG does not necessarily benefit the environment without other policies, as the effects of the multiple end-uses of EG on conventional energy might result in environmental damage. We find that merging an EGA into a global carbon tax system would enhance the effects of carbon tax on CO2 reduction by 33%, and simultaneously lower the GDP loss due to the carbon tax by 75%. The economic benefits from the EGA could offset the costs of other environmental policies. Thus, end-use control and other environmental policies should be considered at both the global and regional levels in the setting of international trade agreements that target EG

    Cushing's syndrome caused by ectopic ACTH secretion from pulmonary tumourlets

    Get PDF
    No Abstrac

    Population, sexual and reproductive health, rights and sustainable development: forging a common agenda.

    No full text
    This article suggests that sexual and reproductive health and rights activists seeking to influence the post-2015 international development paradigm must work with sustainable development advocates concerned with a range of issues, including climate change, environmental issues, and food and water security, and that a way of building bridges with these communities is to demonstrate how sexual and reproductive health and rights are relevant for these issues. An understanding of population dynamics, including urbanization and migration, as well as population growth, can help to clarify these links. This article therefore suggests that whether or not sexual and reproductive health and rights activists can overcome resistance to discussing "population", become more knowledgeable about other sustainable development issues, and work with others in those fields to advance the global sustainable development agenda are crucial questions for the coming months. The article also contends that it is possible to care about population dynamics (including ageing and problems faced by countries with a high proportion of young people) and care about human rights at the same time. It expresses concern that, if sexual and reproductive health and rights advocates do not participate in the population dynamics discourse, the field will be left free for those for whom respecting and protecting rights may be less of a priority
    corecore