Abst~act: This paper studies the management of costs associated with transmission constraints (i.e., transmission congestion costs) in a competitive electricity market. The paper examines two approaches for dealing with these costs. The first approach is based on a nodal pricing framework and forms the basis of the so-calledpool model. The paper also provides an analysis of financial instruments proposed to complement nodal pricing and includes illustrative test results on a large scale system. The second approach is based on cost allocation procedures proposed for the so-called bilateral model. The paper explains the basis for this model including a game-theoretic evaluation of some of its aspects. Both the pool and bilateral models have been at the center of the electric utility restructuring debate in California.

This paper discusses the competitive procurement of Ancillary Services by an Independent System Operator (ISO). The paper assumes the existence of an underlying market for energy and explains why this energy market must be accompanied by a market for Ancillary Services. These services include operating reserves and Automatic Generation Control (AGC) both of which may require generators that are infra-marginal in the energy market to choose between supplying energy or Ancillary Services. The paper discusses the design of an auction for these services that has formed the basis for the Califomia ISO's Ancillary Services market. The paper also discusses the real-time dispatch of Ancillary Services.

ABBREVIATIONS APSAnti-phospholipid syndrome NMDAR N-methyl-D-aspartate receptor PMD Psychogenic movement disorder SLE Systemic lupus erythematosus AIM The purpose of this study was to report a prospective cohort of children with acute-onset movement disorders.METHOD We report on 52 individuals (31 females, 21 males; mean age 6y 5mo, range 2mo-15y) with acute-onset movement disorders managed at a busy tertiary paediatric referral hospital over a 40-month period. RESULTSIn descending order of frequency, the movement disorders reported were chorea, dystonia, tremor, myoclonus, and parkinsonism. It was possible to divide the participants into three groups: (1) those with inflammatory or autoimmune disorders (n=22), (2) those with non-inflammatory disorders (n=18), and (3) those with psychogenic disorders (n=12). The inflammatory or autoimmune aetiologies included N-methyl-D-aspartate receptor encephalitis (n=5), opsoclonusmyoclonus syndrome (n=4), Sydenham chorea (n=3), systemic lupus erythematosus (n=3), acute necrotizing encephalopathy (n=3), and other types of encephalitis (n=4). Other important noninflammatory movement disorder aetiologies included drug-induced movement disorder (n=6), post-pump chorea (n=5), metabolic (n=3) and vascular (n=2) disease. The participants with psychogenic movement disorders (n=12) were all over 10 years of age and were more likely to be female. Tremor and myoclonus were significantly over-represented in the psychogenic movement disorder subgroup. The outcomes of the total cohort were variable, and included full recovery, severe morbidity, and death.

This paper presents a new methodology within the framework of centralized optimization for calculating optimal generation schedules that minimize energy payments by power pool consumers. This paper addresses issues related to market structure and the operation of power pools, such as bid evaluation, generator no-load and start-up cost recovery, generator unit operating constraints, and market clearing price determination. Unlike conventional Unit Commitment algorithms that minimize total energy production costs, the method presented here minimizes payments by power pool consumers. A payment minimization objective leads to a different unit commitment and dispatch solution, and lower market clearing prices. Additionally, optimal allocation of generator no-load and start-up costs over the scheduling period is integrated in the bid evaluation process, leading to a further reduction in consumer payments.

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