High photovoltages in ferroelectric ceramics

The short-circuit currents and photo-emfs were measured for various ceramics including barium titanate, lead metaniobate, and lead titanate. It is suggested that the emfs and currents arise from the presence of photoconductor-insulator sandwiches in the presence of space-charge-produced internal fields. Results are in agreement with the proposed theory and indicate that the ferroelectric ceramics are not only producers of high-voltage photoelectricity but a photo-battery, the polarity and magnitude of which can be switched by application of an electrical signal

Information geometry of density matrices and state estimation

Given a pure state vector |x> and a density matrix rho, the function p(x|rho)= defines a probability density on the space of pure states parameterised by density matrices. The associated Fisher-Rao information measure is used to define a unitary invariant Riemannian metric on the space of density matrices. An alternative derivation of the metric, based on square-root density matrices and trace norms, is provided. This is applied to the problem of quantum-state estimation. In the simplest case of unitary parameter estimation, new higher-order corrections to the uncertainty relations, applicable to general mixed states, are derived.Comment: published versio

Efficient Simulation of Quantum State Reduction

The energy-based stochastic extension of the Schrodinger equation is a rather special nonlinear stochastic differential equation on Hilbert space, involving a single free parameter, that has been shown to be very useful for modelling the phenomenon of quantum state reduction. Here we construct a general closed form solution to this equation, for any given initial condition, in terms of a random variable representing the terminal value of the energy and an independent Brownian motion. The solution is essentially algebraic in character, involving no integration, and is thus suitable as a basis for efficient simulation studies of state reduction in complex systems.Comment: 4 pages, No Figur

Temperature-sensitive mutant strains for isolation of additional mutants of a given site

Use of temperature-sensitive strain

Assay of steady-state level of glucose-6-phosphate

Assay of glucose-6-phosphat

The neighborhood unit concept and the shaping of land planning in the United States 1912-1968

Although one of the more well-known concepts in planning, both planning scholars and professional communities such as the New Urbanism have neglected the neighbourhood unit concept's historic influence in shaping suburban land planning norms. This paper analyzes contemporaneous professional and governmental literature in order to understand the context of land planning and development during the time that the neighbourhood unit became a leading idea. Between 1912 and 1968 the neighbourhood unit concept bridged planning, design, development and policy-making communities to improve standards in the construction of residential environments by shifting the scale of development to an area as a whole. In this time period the neighbourhood unit concept shaped land planning norms, facilitated execution of policies, framed new institutions, and became associated with the changes that it helped to bring about

Survey of the research done on art among schizophrenic children.

Thesis (Ed.M.)--Boston Universit