Interjurisdictional Housing Prices and Spatial Amenities: Which Measures of Housing Prices Reflect Local Public Goods?

Understanding the spatial variation in housing prices plays a crucial role in topics ranging from the cost of living to quality-of-life indices to studies of public goods and household mobility. Yet analysts have not reached a consensus on the best source of such data, variously using self-reported values from the census, transactions values, tax assessments, and rental values. Additionally, while most studies use micro-level data, some have used summary statistics such as the median housing value. Assessing neighborhood price indices in Los Angeles, we find that indices based on transactions prices are highly correlated with indices based on self-reported values, but the former are better correlated with public goods. Moreover, rental values have a higher correlation with public goods and income levels than either asset-value measure. Finally, indices based on median values are poorly correlated with the other indices, public goods, and income.

A posteriori L∞(L^2)-error bounds in finite element approximation of the wave equation

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Change of size and type of patent ductus arteriosus in a one year old infant during routine echocardiographic study

There are only very few publications which document reactivity of patent ductus arteriosus. This report documentes the reactivity of a patent arterial duct in a one year old infant, 6.5 kg weight during a routine echocardiographic color Doppler study. Echocardiographic images were obtained during conscious sedation.peer-reviewe

Heating and Cooling Dynamics of Carbon Nanotubes Observed by Temperature-Jump Spectroscopy and Electron Microscopy

Microscopy imaging indicates that in situ carbon nanotubes (CNTs) irradiation with relatively low dosages of infrared radiation results in significant heating of the tubes to temperatures above 1300 K. Ultrafast temperature-jump experiments reveal that CNTs laser-induced heating and subsequent cooling in solution take tens and hundreds of picoseconds, respectively. Given the reported transient behavior, these observations suggest novel ways for a T-jump methodology, unhindered by the requirement for excitation of water in the study of biological structures. They also provide the rate information needed for optimization of photothermal therapy that invokes infrared irradiation to selectively heat and annihilate cancer cells

Scanning ultrafast electron microscopy

Progress has been made in the development of four-dimensional ultrafast electron microscopy, which enables space-time imaging of structural dynamics in the condensed phase. In ultrafast electron microscopy, the electrons are accelerated, typically to 200 keV, and the microscope operates in the transmission mode. Here, we report the development of scanning ultrafast electron microscopy using a field-emission-source configuration. Scanning of pulses is made in the single-electron mode, for which the pulse contains at most one or a few electrons, thus achieving imaging without the space-charge effect between electrons, and still in ten(s) of seconds. For imaging, the secondary electrons from surface structures are detected, as demonstrated here for material surfaces and biological specimens. By recording backscattered electrons, diffraction patterns from single crystals were also obtained. Scanning pulsed-electron microscopy with the acquired spatiotemporal resolutions, and its efficient heat-dissipation feature, is now poised to provide in situ 4D imaging and with environmental capability