Spatial Economic Theory of Pollution Control under Stochastic Emissions

This paper examines the eectiveness of environmental policies in curtailing pollution of a rm which is operating in a space economy under stochastic emissions. We consider a general n-input planar space production-location model, in which the output is produced jointly with the byproduct pollution. Although production is nonstochastic, the resulting pollution emission is assumed to have a random component, and the polluting rm must make its production and location decisions before the uncertainty is resolved. We provide some propositions concerning the comparative statics of the polluting rm's location choices, urban pollution concentration, and the relative impact of regulation via emission taxes to that of emission standards.location theory, pollution control, emission uncertainty

Spatial Monopoly Pricing in a Stochastic Environment

This paper reexamines the welfare implications of three pricing regimes (mill, uniform and discriminatory) for a monopoly in a stochastic environment. It con-siders a risk-averse monopolist faces two markets with stochastic and linear demands. The monopolist is assumed to commit to an irreversible price in each market before the uncertainty is resolved. Several unconventional results are shown to be triggered by the presence of demand uncertainty. The reason for the reversal of orthodox intuition is the asymmetry in the risk chacteristics of the markets and the willingness of the monopolist to trade increased level of expected prots for reduced risk.spatial pricing, monopoly, demand uncertainty

Functional analysis of Methanocaldococcus jannaschii RNA polymerase A’ ‘bridge-helix’ using a fully automated high-throughput robotic system

RNA polymerases (RNAPs) are the ‘engines’ of cellular transcriptional machineries, which are essential to life and highly conserved from bacteria to eukaryotes. Though crystal structures of both eukaryotic and bacterial RNAPs have been intensively studied, the relationships between structures and appropriate functions of such enzymes in eukaryotes remain unknown since there has not yet been possible to constitute any active eukaryotic RNAPs from recombinant subunits. The successfully assembled archaeal counterparts have provided an alternative approach to study the eukaryotic system due to not only the structural similarities between these enzymes but also the structural and functional similarities of their basal transcriptional machineries. ‘Bridge-helix’ is one of the most highly conserved structures near the catalytic site of RNAPs, which has been proposed to play an important role in coordinating the processing of nucleic acid substrates through the active center. 17 adjacent residues (mjA’-L814 to mjA’-R830) within the central portion of Methanocaldococcus jannaschii A’ ‘bridge-helix’ were chosen for a systematic high-throughput sitedirected mutagenesis approach using a novel robotic system. This robotic system is fully automated without any human interventions that may enormously reduce human errors and effectively increase the number of samples that could be processed in parallel. The results obtained from such high-throughput approach showed a wide spectrum of in vitro phenotypes ranging from complete loss of function to ‘superactivity’. According to the unexpected functional evidences obtained with the ‘superactive’ mutants, we propose a highly favorable kinked ‘bridge-helix’ conformation for the nucleotide addition cycle that has to be precisely localized in certain positions in order to increase the specific activity of RNAPs. The fact that no additive effects have been found so far in any of the ‘superactive’ double mutants suggests that various single amino-acid substitution ‘superactive’ mutants may affect the same process in a functionally overlapping and mutually independent manner

Three new and remarkable species of mosses from China and the Philippines

Distichophyllum meizhii Tan & Lin and D. wanianum Tan & Lin (Hookeriaceae) collected from southwestern region of China are described as new to science. Also, Horikawaea redfearnii Tan & Lin is described as a new species based on collections from Hainan Island of China and Palawan Island of the Philippines. The sporophytic specimen of Horikawaea Nog. was collected for the first time and support a family placement in Pterobryaceae

Thermoelectric power and heats of transport of the alkali-halides

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