1,599 research outputs found
Policy Analysis in a Second-Best World
This paper first describes the new literature in environmental economics on the so-called "double dividend" and then explores its implications for a broad range of economic issues. The basic finding in this literature is that in a second-best, general equilibrium setting, environmental measures raise costs and prices and thereby reduce the real wage. This rise in the cost of living reduces slightly the quantity of labor supplied in an already highly distorted labor market, giving rise to losses in social welfare that can be large relative to the basic welfare gains from improved environmental policy. These losses may be offset to some extent by using revenues (if any) from the environmental programs to reduce existing taxes on labor. This same line of analysis applies to many programs and institutions in the economy that raise the cost of living: tariffs and quotas on imports, agricultural price-support programs, monopoly pricing, programs of occupational licensure that limit entry, and many others. The paper thus suggests that traditional, partial equilibrium benefit-cost analysis has, in many instances, unwittingly omitted a potentially quite significant class of social costs from the calculations.
An innovative framework for selecting sustainable options to reduce the risk of soil erosion and environmental pollution incidents on road construction sites
Notes sobre els tres treballs per Barcelona
El autor, artista plástico, comenta las obras presentadas en Barcelona, todas ellas compuestas a partir de tres elementos (fotografĂa, texto, textura) y enmarcables en un mundo oscilante entre la modernidad y la ruina, entre la ironĂa y la melancolĂa.The author, an artist himself, discusses a number of works presented in Barcelona, each comprising three elements (photograph, text, texture) and capable of being framed in a world which oscillates between modernity and ruin, between irony and melancholy
Werner Mittenzwei: Exil in der Schweiz
Leipzig: Reclam, 1978. (Kunst und Literatur im antifaschistischen Exil, 2), 447 p., 4,- M
Sands through the hourglass the structural and functional diversity of major intrinsic proteins
Major Intrinsic Proteins (MIPs) are an ancient family of integral membrane proteins that mediate the bidirectional flux of water and small solutes across cellular membranes. Genomic and phylogenetic analyses indicate that plants contain more MIP genes than their animal and microbial counterparts. An analysis of MIP structure also indicates that plant MIPs structurally diverse at the regions that control selectivity of these proteins. Homology modeling was performed using all 35 members of the MIP family from Arabidopsis thaliana. This analysis revealed that MIPs can be divided into 8 functional subgroups based on the amino acids in their selectivity determining ar/R regions. A broader phylogenetic analysis of all available MIP sequences indicates that 92 ar/R regions exist in this dataset, and that much of the diversity arises from plant sources.Homology modeling indicated that the Nodulin 26-like intrinsic protein (NIP) family of Arabidopsis could be divided into two subgroups based on ar/R classification: NIP subgroup I and II. Functional analysis indicates that these two subgroups are functionally distinct. NIP subgroup I forms aquaglyceroporin channels that are also permeable to ammonia, while NIP subgroup II channels are impermeable to water and capable of transporting larger solutes, such as urea. Site-directed mutagenesis studies were used to rationally interconvert the selectivity of these proteins by amino acid substitutions in the ar/R region. Finally, it was demonstrated that members of NIP subgroup II in Arabidopsis form physiologically relevant boric acid channels at the plasma membrane. Nodulin 26, the archetypal NIP, is phosphorylated by a calcium dependant protein kinase (CDPK) at Ser 262 in its C-terminus. This study demonstrates that nodulin 26 phosphorylation increases the water permeability of the channel.In addition, the C-terminus was found to constitute a protein interaction site for nodule cytosolic glutamine synthetase. Finally, the study was extended to characterize MIP channels from the common pea aphid (ApAQP1 and ApAQP2). The results indicate that ApAQP1 is a water-selective aquaporin that is involved in aphid gut osmoregulation, while ApAQP2 is a water channel that is permeable to an array of linear polyols. The potential physiological function of this channel is also discussed
Russia and the Restricted Composer: Limitations of the Self, Culture, and Government
This paper will consider the various creative limitations that have inhibited Russian and Soviet composers throughout history. These restrictions will be classified into three broad areas: those of the self, those of culture, and those of government. As will be seen, individual Russian composers have been constrained in at least one of these areas. Consideration of important musical and historical figures, from the beginning of the 19th century through the later decades of the Soviet Union, will assist in presenting specific forms of restraint
The Development of explosives competencies, training and education in the UK
Competent explosives workers in the Armed Forces and in the civil sector are
critical to the safe production, testing and use of explosives. Moreover we need
competent explosives specialists to combat the challenge from terrorism and
clean up the planet from the explosive hazards that are the legacy of past
conflicts. Unfortunately many countries are witnessing a significant loss of
capability in this area and are looking at ways of replenishing vital expertise.
This paper describes the work done in recent years by the authors and others in
the UK to establish numbers of people working in the sector and to consider the
skills and knowledge required to carry out their work. It outlines the concept
of national occupational standards and the framework of professional and
vocational qualifications that are available or are being developed for
explosives specialists. It also describes some of the educational and e-learning
programmes designed to support this initiative. Ultimately the aim is to address
the professionalism of all personnel who deal with explosives in order to reduce
the incidence and consequence of accidents and maintain national capability
Airline planning benchmark problems—Part II : passenger groups, utility and demand allocation
This paper is the second of two papers entitled “Airline Planning Benchmark Problems”, aimed at developing benchmark data that can be used to stimulate innovation in airline planning, in particular, in flight schedule design and fleet assignment. The former has, to date, been under-represented in the optimisation literature, due in part to the difficulty of obtaining data that adequately reflects passenger choice, and hence schedule revenue. Revenue models in airline planning optimisation only roughly approximate the passenger decision process. However, there is a growing body of literature giving empirical insights into airline passenger choice. Here we propose a new paradigm for passenger modelling, that enriches our representation of passenger revenue, in a form designed to be useful for optimisation. We divide the market demand into market segments, or passenger groups, according to characteristics that differentiate behaviour in terms of airline product selection. Each passenger group has an origin, destination, size (number of passengers), departure time window, and departure time utility curve, indicating willingness to pay for departure in time sub-windows. Taking as input market demand for each origin–destination pair, we describe a process by which we construct realistic passenger group data, based on the analysis of empirical airline data collected by our industry partner. We give the results of that analysis, and describe 33 benchmark instances produced
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