The Long Run Demand for Lighting: Elasticities and Rebound Effects in Different Phases of Economic Development

The provision of artificial light was revolutionised by a series of discontinuous innovations in lighting appliances, fuels, infrastructures and institutions during the nineteenth and twentieth centuries. In Britain, the real price of lighting fell dramatically (3,000-fold between 1800 and 2000) and quality rose. Along with rises in real income and population, these developments meant that total consumption of lighting was 40,000 times greater by2000 than in 1800. The paper presents estimates of the income and price elasticities of demand for lighting services over the past three hundred years, and explores how they evolved. Income and price elasticities increased dramatically (to 3.5 and -1.7, respectively) between the 1840s and the 1890s and fell rapidly in the twentieth century. Even in the twentieth century and at the beginning of the twenty-first century, rebound effects in the lighting market still appear to be potentially important. This paper provides a first case study of the long run effects of socio-economic change and technological innovation on the consumption of energy services in the UK. We suggest that understanding the evolution of the demand for energy services and the factors that influence it contributes to a better understanding of future energy uses and associated greenhouse gas emissions.Energy Services, Demand, Economic Development, Rebound Effect

Aerosol number-to-volume-relationship and relative humidity in the eastern Atlantic

J. Geophys. Res ., 105, 1987-1995.Measurementsa cquiredf rom the Office of Naval Research( ONR) Pelican research aircraftd uringt he secondA erosolC haracterizationE xperiment( ACE 2) are analyzedt o derive valuesf or the dry (RH = 40%) aerosonl umber-to-volumrea tio in the submicrons izer ange. This ratioi s foundto ber elativelyc onstanwt,i tha meanv alueo f 168_ +2 1 gm- 3,i n agreemenwti th previouss tudiese lsewhere.T he impacto f ambientr elativeh umidity (RH) on the dry number-to-volumies alsoq uantifieda nd a procedurefo r estimatingth e dry from the ambientr atio established.F inally, the feasibilityo f a remoter etrievalo f the aerosoln umberc oncentrationin the submicrons izer ange,e ssentiallyth e cloudc ondensation ucleusc oncentrationa ctive at a nominal0 .2% supersaturationis, partially assessed

The Bethe-Ansatz for N=4 Super Yang-Mills

We derive the one loop mixing matrix for anomalous dimensions in N=4 Super Yang-Mills. We show that this matrix can be identified with the Hamiltonian of an integrable SO(6) spin chain with vector sites. We then use the Bethe ansatz to find a recipe for computing anomalous dimensions for a wide range of operators. We give exact results for BMN operators with two impurities and results up to and including first order 1/J corrections for BMN operators with many impurities. We then use a result of Reshetikhin's to find the exact one-loop anomalous dimension for an SO(6) singlet in the limit of large bare dimension. We also show that this last anomalous dimension is proportional to the square root of the string level in the weak coupling limit.Comment: 35 pages, 3 figures, LaTeX; v2 references added, typos corrected, \Lambda fixed; v3 expanded discussion of higher loops in conclusion, matches published versio

Stringing Spins and Spinning Strings

We apply recently developed integrable spin chain and dilatation operator techniques in order to compute the planar one-loop anomalous dimensions for certain operators containing a large number of scalar fields in N =4 Super Yang-Mills. The first set of operators, belonging to the SO(6) representations [J,L-2J,J], interpolate smoothly between the BMN case of two impurities (J=2) and the extreme case where the number of impurities equals half the total number of fields (J=L/2). The result for this particular [J,0,J] operator is smaller than the anomalous dimension derived by Frolov and Tseytlin [hep-th/0304255] for a semiclassical string configuration which is the dual of a gauge invariant operator in the same representation. We then identify a second set of operators which also belong to [J,L-2J,J] representations, but which do not have a BMN limit. In this case the anomalous dimension of the [J,0,J] operator does match the Frolov-Tseytlin prediction. We also show that the fluctuation spectra for this [J,0,J] operator is consistent with the string prediction.Comment: 27 pages, 4 figures, LaTex; v2 reference added, typos fixe

The superstring Hagedorn temperature in a pp-wave background

The thermodynamics of type IIB superstring theory in the maximally supersymmetric plane wave background is studied. We compute the thermodynamic partition function for non-interacting strings exactly and the result differs slightly from previous computations. We clarify some of the issues related to the Hagedorn temperature in the limits of small and large constant RR 5-form. We study the thermodynamic behavior of strings in the case of $AdS_3 \times S^3 \times T^4$ geometries in the presence of NS-NS and RR 3-form backgrounds. We also comment on the relationship of string thermodynamics and the thermodynamic behavior of the sector of Yang-Mills theory which is the holographic dual of the string theory.Comment: 22 pages, JHEP style, minor misprints corrected, some comments adde

Challenges of the transition to a low carbon, more electric future:From here to 2050

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PV cohomology of pinwheel tilings, their integer group of coinvariants and gap-labelling

In this paper, we first remind how we can see the "hull" of the pinwheel tiling as an inverse limit of simplicial complexes (Anderson and Putnam) and we then adapt the PV cohomology introduced in a paper of Bellissard and Savinien to define it for pinwheel tilings. We then prove that this cohomology is isomorphic to the integer \v{C}ech cohomology of the quotient of the hull by $S^1$ which let us prove that the top integer \v{C}ech cohomology of the hull is in fact the integer group of coinvariants on some transversal of the hull. The gap-labelling for pinwheel tilings is then proved and we end this article by an explicit computation of this gap-labelling, showing that \mu^t \big(C(\Xi,\ZZ) \big) = \dfrac{1}{264} \ZZ [\dfrac{1}{5}].Comment: Problems of compilation by arxiv for figures on p.6 and p.7. I have only changed these figure

A Model for the Development of the Rhizobial and Arbuscular Mycorrhizal Symbioses in Legumes and Its Use to Understand the Roles of Ethylene in the Establishment of these two Symbioses

We propose a model depicting the development of nodulation and arbuscular mycorrhizae. Both processes are dissected into many steps, using Pisum sativum L. nodulation mutants as a guideline. For nodulation, we distinguish two main developmental programs, one epidermal and one cortical. Whereas Nod factors alone affect the cortical program, bacteria are required to trigger the epidermal events. We propose that the two programs of the rhizobial symbiosis evolved separately and that, over time, they came to function together. The distinction between these two programs does not exist for arbuscular mycorrhizae development despite events occurring in both root tissues. Mutations that affect both symbioses are restricted to the epidermal program. We propose here sites of action and potential roles for ethylene during the formation of the two symbioses with a specific hypothesis for nodule organogenesis. Assuming the epidermis does not make ethylene, the microsymbionts probably first encounter a regulatory level of ethylene at the epidermis–outermost cortical cell layer interface. Depending on the hormone concentrations there, infection will either progress or be blocked. In the former case, ethylene affects the cortex cytoskeleton, allowing reorganization that facilitates infection; in the latter case, ethylene acts on several enzymes that interfere with infection thread growth, causing it to abort. Throughout this review, the difficulty of generalizing the roles of ethylene is emphasized and numerous examples are given to demonstrate the diversity that exists in plants

SHCal20 Southern Hemisphere Calibration, 0–55,000 Years cal BP

Early researchers of radiocarbon levels in Southern Hemisphere tree rings identified a variable North-South hemispheric offset, necessitating construction of a separate radiocarbon calibration curve for the South. We present here SHCal20, a revised calibration curve from 0–55,000 cal BP, based upon SHCal13 and fortified by the addition of 14 new tree-ring data sets in the 2140–0, 3520–3453, 3608–3590 and 13,140–11,375 cal BP time intervals. We detail the statistical approaches used for curve construction and present recommendations for the use of the Northern Hemisphere curve (IntCal20), the Southern Hemisphere curve (SHCal20) and suggest where application of an equal mixture of the curves might be more appropriate. Using our Bayesian spline with errors-in-variables methodology, and based upon a comparison of Southern Hemisphere tree-ring data compared with contemporaneous Northern Hemisphere data, we estimate the mean Southern Hemisphere offset to be 36 ± 27 14C yrs older