Mesoscopic Thermovoltage Measurement Design

Quantitative thermoelectric measurements in the mesoscopic regime require accurate knowledge of temperature, thermovoltage, and device energy scales. We consider the effect of a finite load resistance on thermovoltage measurements of InAs/InP heterostructure nanowires. Load resistance and ac attenuation distort the measured thermovoltage therefore complicating the evaluation of device performance. Understanding these effects improves experimental design and data interpretation.Comment: 2 pages, 3 figure

Radiative Characteristics of Clouds in the Infrared

Infrared radiative neat transfer in and through clouds, thermal emission effects and atmospheric scatterin

Revealed cardinal preference

I prove that as long as we allow the marginal utility for money (lambda) to vary between purchases (similarly to the budget) then the quasi-linear and the ordinal budget-constrained models rationalize the same data. However, we know that lambda is approximately constant. I provide a simple constructive proof for the necessary and sufficient condition for the constant lambda rationalization, which I argue should replace the Generalized Axiom of Revealed Preference in empirical studies of consumer behavior. 'Go Cardinals!' It is the minimal requirement of any scientifi c theory that it is consistent with the data it is trying to explain. In the case of (Hicksian) consumer theory it was revealed preference -introduced by Samuelson (1938,1948) - that provided an empirical test to satisfy this need. At that time most of economic reasoning was done in terms of a competitive general equilibrium, a concept abstract enough so that it can be built on the ordinal preferences over baskets of goods - even if the extremely specialized ones of Arrow and Debreu. However, starting in the sixties, economics has moved beyond the 'invisible hand' explanation of how -even competitive- markets operate. A seemingly unavoidable step of this 'revolution' was that ever since, most economic research has been carried out in a partial equilibrium context. Now, the partial equilibrium approach does not mean that the rest of the markets are ignored, rather that they are held constant. In other words, there is a special commodity -call it money - that reflects the trade-offs of moving purchasing power across markets. As a result, the basic building block of consumer behavior in partial equilibrium is no longer the consumer's preferences over goods, rather her valuation of them, in terms of money. This new paradigm necessitates a new theory of revealed preference

Study of the ammonia ice cloud layer in the north tropical zone of Jupiter from the infrared interferometric experiment on Voyager

An average of 51 Voyager 1 IRIS spectra of Jupiter's North Tropical Zone was analyzed to infer the abundance, vertical extent, and size distribution of the particles making up the ammonia cloud in this region. It is assumed that the cloud base coincides with the level at which 100% saturation of ammonia vapor occurs. The vertical distribution of particulates above this level is determined by assuming a constant total ammonia mixing ratio and adjusting the two phases so that the vapor is saturated throughout the cloud. A constant scaling factor then adjusts the base number density. A radiative transfer program is used that includes the effects of absorption and emission of all relevant gases as well as anisotropic scattering by cloud particles. Mie scattering from a gaussian particle size distribution is assumed. The vertical thermal structure is inferred from a temperature retrieval program that utilizes the collision induced S(0) and S(1) molecular hydrogen lines between 300 and 700.cm, and the 1304.cm methane band

Inside the Economist's Mind: The History of Modern Economic Thought, as Explained by Those Who Produced It

This is the front matter from a book of interviews to be published by Blackwell. The book is coedited by W. A. Barnett and P. A. Samuelson. The front matter includes the Table of Contents, Coeditor Preface by W. A. Barnett, Coeditor Foreword by Paul A. Samuelson, and History of Thought Introduction by E. Roy Weintraub. The front matter highlights some of the more startling and controversial statements contained in the interviews and puts the interviews into context relative to the history of modern economic thought. The interviews reprinted in this book include: (1) Wassily Leontief interviewed by Duncan Foley. (2) David Cass interviewed jointly by Steven Spear and Randall Wright. (3) Robert E. Lucas interviewed by Bennett T. McCallum. (4) Janos Kornai interviewed by Olivier Blanchard. (5) Franco Modigliani interviewed by William Barnett and Robert Solow. (6) Milton Friedman interviewed by John Taylor. (7) Paul A. Samuelson interviewed by William A. Barnett. (8) Paul Volcker interviewed by Perry Mehrling. (9) Martin Feldstein interviewed by James Poterba. (10) Christopher Sims interviewed by Lars Peter Hansen. (11) Robert Shiller interviewed by John Campbell. (12) Stanley Fischer interviewed by Olivier Blanchard. (13) Jacques Drèze interviewed by Pierre Dehez and Omar Licandro. (14) Tom Sargent interviewed by George Evans and Seppo Honkapohja. (15) Robert Aumann interviewed by Sergiu Hart. (16) James Tobin and Robert Shiller interviewed by David Colander.history of economic thought, Samuelson, macroeconomics, microeconomics, policy, interviews

Tunable effective g-factor in InAs nanowire quantum dots

We report tunneling spectroscopy measurements of the Zeeman spin splitting in InAs few-electron quantum dots. The dots are formed between two InP barriers in InAs nanowires with a wurtzite crystal structure grown by chemical beam epitaxy. The values of the electron g-factors of the first few electrons entering the dot are found to strongly depend on dot size and range from close to the InAs bulk value in large dots |g^*|=13 down to |g^*|=2.3 for the smallest dots. These findings are discussed in view of a simple model.Comment: 4 pages, 3 figure

Fractal Markets Hypothesis and the Global Financial Crisis: Scaling, Investment Horizons and Liquidity

We investigate whether fractal markets hypothesis and its focus on liquidity and invest- ment horizons give reasonable predictions about dynamics of the financial markets during the turbulences such as the Global Financial Crisis of late 2000s. Compared to the mainstream efficient markets hypothesis, fractal markets hypothesis considers financial markets as com- plex systems consisting of many heterogenous agents, which are distinguishable mainly with respect to their investment horizon. In the paper, several novel measures of trading activity at different investment horizons are introduced through scaling of variance of the underlying processes. On the three most liquid US indices - DJI, NASDAQ and S&P500 - we show that predictions of fractal markets hypothesis actually fit the observed behavior quite well.Comment: 11 pages, 3 figure

Urbanisation is associated with reduced Nosema sp. infection, higher colony strength and higher richness of foraged pollen in honeybees

Bees are vital pollinators, but are faced with numerous threats that include loss of floral resources and emerging parasites amongst others. Urbanisation is a rapidly expanding driver of land-use change that may interact with these two major threats to bees. Here we investigated effects of urbanisation on food store quality and colony health in honeybees (Apis mellifera) by sampling 51 hives in four different land-use categories: urban, suburban, rural open and rural wooded during two seasons (spring and autumn). We found positive effects of urban land use on colony strength and richness of stored pollen morphotypes, alongside lower late-season Nosema sp. infection in urban and suburban colonies. Our results reveal that honeybees exhibit lower colony performance in strength in rural areas, adding to the growing evidence that modern agricultural landscapes can constitute poor habitat for insect pollinators