8,022 research outputs found
The subzero microbiome: Microbial activity in frozen and thawing soils
No full textMost of the Earth's biosphere is characterized by low temperatures (<5 °C) and cold-adapted microorganisms are widespread. These psychrophiles have evolved a complex range of adaptations of all cellular constituents to counteract the potentially deleterious effects of low kinetic energy environments and the freezing of water. Microbial life continues into the subzero temperature range, and this activity contributes to carbon and nitrogen flux in and out of ecosystems, ultimately affecting global processes. Microbial responses to climate warming and in particular, thawing of frozen soils are not yet well understood although the threat of microbial contribution to positive feedback of carbon flux is substantial. To date, several studies have examined microbial community dynamics in frozen soils and permafrost due to changing environmental conditions, and some have undertaken the complicated task of characterizing microbial functional groups and how their activity changes with changing conditions, either in situ or by isolating and characterizing macromolecules. With increasing temperature and wetter conditions microbial activity of key microbes and subsequent efflux of greenhouse gases also increase. In this review, we aim to provide an overview of microbial activity in seasonally frozen soils and permafrost. With a more detailed understanding of the microbiological activities in these vulnerable soil ecosystems, we can begin to predict and model future expectations for carbon release and climate change.Peer reviewe
Ab Initio Calculations Show Why m-Phenylene Is Not Always a Ferromagnetic Coupler
No full textIn agreement with the experimental results of the groups of Rassat and Iwamura on respectively m-phenylene
bis(tert-butyl nitroxides) 2 and 3, ab initio calculations on m-benzoquinodimethane (la) and m-phenylene bis(nitroxide)
(la) find that near dihedral angles of 4 = 90" between the benzene ring and the radical-bearing groups, the singlet
falls below the triplet in energy. The change in m-phenylene from a ferromagnetic coupler at angles around 4 = 0" to an antiferromagnetic coupler around 4 = 90" is found to be largely due to selective destabilization of the
antisymmetric (A) combination of the singly-occupied orbitals on each of the radical centers by a u orbital of this symmetry on the m-phenylene coupler. The asymmetry about 4 = 90" in the singlet-triplet energy difference that
is calculated for Id is shown to be due to additional interactions of the oxygens of the singly-occupied nitroxyl
orbitals with p-n AOs of the benzene ring
Stability of a spherical flame ball in a porous medium
No full textGaseous flame balls and their stability to symmetric disturbances are studied numerically and asymptotically, for large activation temperature, within a porous medium that serves only to exchange heat with the gas. Heat losses to a distant ambient environment, affecting only the gas, are taken to be radiative in nature and are represented using two alternative models. One of these treats the heat loss as being constant in the burnt gases and linearizes the radiative law in the unburnt gas (as has been studied elsewhere without the presence of a solid). The other does not distinguish between burnt and unburnt gas and is a continuous dimensionless form of Stefan's law, having a linear part that dominates close to ambient temperatures and a fourth power that dominates at higher temperatures.Numerical results are found to require unusually large activation temperatures in order to approach the asymptotic results. The latter involve two branches of solution, a smaller and a larger flame ball, provided heat losses are not too high. The two radiative heat loss models give completely analogous steady asymptotic solutions, to leading order, that are also unaffected by the presence of the solid which therefore only influences their stability. For moderate values of the dimensionless heat-transfer time between the solid and gas all flame balls are unstable for Lewis numbers greater than unity. At Lewis numbers less than unity, part of the branch of larger flame balls becomes stable, solutions with the continuous radiative law being stable over a narrower range of parameters. In both cases, for moderate heat-transfer times, the stable region is increased by the heat capacity of the solid in a way that amounts, simply, to decreasing an effective Lewis number for determining stability, just as if the heat-transfer time was zero
Interaction of flexible filaments with the wake of cylinder at low Reynolds numbers
No full textThis work is the very first attempt to understand and optimize the configuration of flexible filaments placed on the lee side of a bluff body to manipulate flow transitions and bifurcations. It is found that the presence of a sparse set of flexible filaments on the lee side of a cylinder can interfere with the 2D-3D transition process resulting in elongation of recirculation bubble, inhibition of higher order unstable modes, and narrowing the global energy content about a particular shedding frequency. Filaments become effective when spacing between them is smaller than the dominant unstable mode at each particular Reynolds number, i.e. A and B modes
Mie scattering captures observed optical properties of ambient biomass burning plumes assuming uniform black, brown, and organic carbon mixtures
No full textMie scattering captures observed optical properties of ambient biomass burning plumes assuming uniform black, brown, and organic carbon mixtures
Citation: Chylek, P., Lee, J. E., Romonosky, D. E., Gallo, F., Lou, S., Shrivastava, M., Carrico, C. M., Aiken, A. C., Dubey, M. K. (2019), Mie scattering captures observed optical properties of ambient biomass burning plumes assuming uniform black, brown, and organic carbon mixtures. J. Geophys. Res. Atmopsheres.
Corresponding Author: Chylek, P.
Email: [email protected]
Data Description:
Summary of SSA and AAE values for laboratory burns. Fuel for Laboratory burns was approximately 50 g of masticated material. A resistance heater, approximately 700 C, was used to ignite burns. SSA and AAE values are time weighted average and standard deviation
Auto-regulating New Media
No full textUsing Foucault's (1977, 1978) notion of panoptic method of governmentality and looking at the case of Singapore's Internet policy, this paper attempts to expand on the idea-and ideals-of 'auto-regulation'(Lee, 2000, pp. 4-5; Lee & Birch, 2000). Auto-regulation, as I shall posit in this paper, provides a way for regulatory enforcement and surveillance to become sufficiently transparent and 'normalised' so that 'the exercise of power may be supervised by society as a whole'(Foucault, 1977, pp.207-208) rather than by a select group of policy and law enforcement officers, or civil society /activist groups
The Marble Man: Images Depict Lee, His Friends, And His Legend
No full textRobert E. Lee: An Album tells of Lee\u27s life through images. This book is an album in the literal sense, author Emory M. Thomas explains. It contains pictures, contemporary with Lee and with us, of places associated with Lee. It includes pictures of people Lee knew and pictures of Lee. Here...
God and Mrs Thatcher : religion and politics in 1980s Britain
No full textThe core theme of this thesis explores the evolving position of religion in the British public
realm in the 1980s. Recent scholarship on modern religious history has sought to relocate
Britain's "secularization moment" from the industrialization of the nineteenth century to the
social and cultural upheavals of the 1960s. My thesis seeks to add to this debate by examining
the way in which the established Church and Christian doctrine continued to play a central
role in the politics of the 1980s. More specifically it analyses the conflict between the
Conservative party and the once labelled "Tory party at Prayer", the Church of England.
Both Church and state during this period were at loggerheads, projecting contrasting
visions of the Christian underpinnings of the nation's political values.
The first part of this thesis addresses the established Church. It begins with an
examination of how the Church defined its role as the "conscience of the nation" in a period
of national fragmentation and political polarization. It then goes onto explore how the
Anglican leadership, Church activists and associated pressure groups together subjected
Thatcherite neo-liberal economics to moral scrutiny and upheld social democratic values as the
essence of Christian doctrine. The next chapter analyses how the Church conceptualized
Christian citizenship and the problems it encountered when it disseminated this message to its
parishioners.
The second half of this study focuses on the contribution of Christian thought to the
New Right. Firstly, it explores the parallels between political and religious conservatism in this
period and the widespread disaffection with liberal Anglicanism, revealing how Parliament
became one of the central platforms for the traditionalist Anglican cause. Secondly, it
demonstrates how those on the right argued for the Christian basis of economic liberalism and
of the moral superiority of capitalism over socialism. The next chapter focuses on the public
doctrine of Margaret Thatcher, detailing how she drew upon Christian doctrine, language and
imagery to help shape and legitimise her political vision and reinforce her authority as
leader. Finally, the epilogue traces the why this Christian-centric dialogue between the
Church and Conservative government eventually dissipated and was superseded by a much
more fundamental issue in the 1990s as both the ruling elite and the Church were forced to
recognise the religious diversity within British society
Biography of Mary Jane Oliver
No full textTypescript of a sketch biography about Mary Jane (Oliver) Barlow, who came came from England around 1851 and with her husband, Oswald Barlow, helped to settle Saint George. Author unknown, but copied on January 13, 1937 by Virginia M. Lee of the Federal Writers Project, WPA, at Ogden, Uta
P01-330 - Dreaming Brain and Acculturative Mind
No full textAuthor intends to explicate dreaming brain and mind interactions by interpreting the neurophenomenology of dreaming brain as well as by analyzing the narratives of collected dream data. The author articulates acculturative dreaming mind by demonstrating two empirical research outcomes and suggests some analogical connections between dreaming brain and acculturative dreaming mind.The author explored an acculturative dreaming model by analyzing dream data that show an unconscious self-adaptation or acculturative self-process. The author designed “Lee Acculturation Dream Scale” (Lee, Sang Bok, 2005: Psychological Reports, 96, 454-456) to analyze the location of each dream by evaluating the dream content. A two-sample t test on the mean score of the “Lee Acculturation Dream Scale” indicated significant difference between men and women (Lee, 2005).In terms of domain-specific dreaming mind the author analyzed the dreamers’ anxiety level by evaluating the dream content. A sample t test on the “Lee Cross-cultural Anxiety Dream Scale”(Lee, Sang Bok, 2008) means showed significant difference between the two groups(p< 0.001): Korean college students group (N=93, M=1.7, SD=1.2) and Korean-American college student group (N=165, M=2.3, SD=1.5). In this study, Korean American college students, who were experiencing cross-cultural life situation and under acculturation process in the USA, showed more anxiety in their dream contents than Korean college students.Dreaming brain and mind need to be recapitulated as having inherently acculturative function regardless of cultural origins, value or life-style difference.</jats:p
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