Trapping of transuranium elements by the earth's magnetic field

The search for a transuranium element component of cosmic radiation has been carried out in high altitude balloon experiments. The trapping of high Z elements on orbits in the Earth's magnetic field may lead to a sufficient enhancement of the intensity of particle flux to make it possible to detect these elements by satellite experiments. Calculations are presented that predict the behavior of trapped particles as a function of the predicted flux and energy distribution of high Z elements incident on the Earth's magnetic field. Techniques are suggested for the detection of such particles. In addition, the possibility of production of transuranium elements in the recently discovered pulsars are discussed

Putting time into proof outlines

A logic for reasoning about timing of concurrent programs is presented. The logic is based on proof outlines and can handle maximal parallelism as well as resource-constrained execution environments. The correctness proof for a mutual exclusion protocol that uses execution timings in a subtle way illustrates the logic in action

Operational Semantics of Process Monitors

CSPe is a specification language for runtime monitors that can directly express concurrency in a bottom-up manner that composes the system from simpler, interacting components. It includes constructs to explicitly flag failures to the monitor, which unlike deadlocks and livelocks in conventional process algebras, propagate globally and aborts the whole system's execution. Although CSPe has a trace semantics along with an implementation demonstrating acceptable performance, it lacks an operational semantics. An operational semantics is not only more accessible than trace semantics but also indispensable for ensuring the correctness of the implementation. Furthermore, a process algebra like CSPe admits multiple denotational semantics appropriate for different purposes, and an operational semantics is the basis for justifying such semantics' integrity and relevance. In this paper, we develop an SOS-style operational semantics for CSPe, which properly accounts for explicit failures and will serve as a basis for further study of its properties, its optimization, and its use in runtime verification

Economic Development and the Timing and Components of Population Growth

This paper examines the relationship between population growth and economic growth in developing countries from 1965 to 1985. Our results indicate that developing countries were able to shift their labor force from low-productivity agriculture to the higher-productivity industry and service sectors, and to increase productivity within those sectors, despite the rapid growth of their populations. We also find that at given rates of population growth, income growth is related to the time path of population growth and that population growth due to high birth and death rates is associated with slower income growth than population growth due to relatively low birth and death rates. Hence, the timing and components of population growth are important elements in the process of economic development.

The "Youth Problem": Age or Generational Crowding?

This paper attempts to distinguish between two alternative views of the labor market problems faced by young workers in a number of industrialized countries in the 1970s and early 1980s. The first view is that the low relative earnings and high unemployment rates experienced by these workers were largely "age" related. Although this view carries the implication that the problems will disappear for recent youth cohorts as they grow older, it also implies that the problems will be "handed over" to successive waves of youth cohorts as they enter the labor market. The second view is that the labor market problems of recent youth cohorts are a consequence of their large size. This view has very different implications since generational crowding can permanently or temporarily depress the economic position of large cohorts but need not have an adverse effect on later waves of smaller youth cohorts. On the basis of a multicountry empirical analysis of patterns ofcohort size, earnings, unemployment, and the distribution of young workers across industries, we have four main sets of findings to report. First, the baby-boom was not uniformly experienced across OECD economies - in terms of either its timing or magnitude. While some countries, such as Canada, the U.S., and Belgium had large increases in the youth share ofthe population from 1965 to 1980, others, notably Japan and Switzerland, had large decreases. Second, our empirical results indicate that large cohort size tends to have a negative effect on the "expected relative earnings" of the cohort, where expected relative earnings is defined as the product of the earnings and the employment-to-labor force ratio of a young cohort relative to the same product for an older cohort. There is, moreover, a marked trade-off betweenthe relative earnings effect and the relative employment effect with large cohort sizes reducing relative earnings in some countries and reducing reiative employment in others. Third, at least for the U.S., the relatively low wages and high unemployment of the "unlucky cohorts" tend to converge to the patterns that would have resulted had the cohorts been more "normal" in size, with the convergence occurring within a decade or so. Fourth, our results show that baby-boom cohorts were absorbed inthe U.S. and other OECD economies quite evenly across a wide range of industries. This finding contradicts the popular belief that large youth cohorts were absorbed primarily through expansion of those industries that have been traditionally youth-intensive.

Population Growth, Labor Supply, and Employment in Developing Countries

The economies of the less developed countries are about to face perhaps the greatest challenge in their histories: generating a sufficient number of jobs at reasonable wages to absorb their rapidly growing populations into productive employment. In terms of absolute magnitude, this challenge has no precedent in human history. In some respects, this challenge is also unprecedented in terms of its nature, given, on the one hand, the limited availability of natural resources in many countries and, on the other hand,the widespread availability of advanced technology.This paper examines the nature and magnitude of the principal effects of population growth on labor supply and employment in the developing economies of the world. On the supply side of labor markets, we discuss key features of the interrelations between population growth and the labor force. These include the lags between population growth and labor force participation; the independent effects on labor supply of accelerated population growth due to changes in fertility, mortality, and migration; patterns and trends in labor force participation rates; and gender differences in labor supply behavior. On the demand side, we describe and analyze the nature of labor markets in developing economies and attempt to identify the key factors that condition their labor absorption capacity. Descriptive statistics on the characteristics of developing country labor markets and on the relationships between population growth, labor supply, employment shifts, and growth of output per worker are presented and discussed.The key result of our analysis is that, despite the unprecedented magnitude of population growth and the existence of imperfections in labor markets, developing economies tended to shift between 1960 and 1980, from low-productivity agriculture to the higher productivity service and industrial sectors and, albeit with some exceptions, to raise real income per capita. With respect to their prospects for the remainder of this century, we also conclude that Malthusian disasters will not necessarily be the result of forecasted population growth, provided the developing economies can generate human and physical capital investments of comparable relative magnitudes to the past two decades. However, on the basis of past history, the middle-income developing countries are likely to perform better in this respect than the low-income countries, some of whom may need considerable help if they are to absorb increased population while shifting labor to more productive sectors and raising output per worker.

Mountain building processes in the Central Andes

False color composite images of the Thematic Mapper (TM) bands 5, 4, and 2 were examined to make visual interpretations of geological features. The use of the roam mode of image display with the International Imaging Systems (IIS) System 600 image processing package running on the IIS Model 75 was very useful. Several areas in which good comparisons with ground data existed, were examined in detail. Parallel to the visual approach, image processing methods are being developed which allow the complete use of the seven TM bands. The data was organized into easily accessible files and a visual cataloging of the quads (quarter TM scenes) with preliminary registration with the best available charts for the region. The catalog has proved to be a valuable tool for the rapid scanning of quads for a specific investigation. Integration of the data into a complete approach to the problems of uplift, deformation, and magnetism in relation to the Nazca-South American plate interaction is at an initial stage

Perceived Cognitive Changes with Chemotherapy for Breast Cancer: A Pilot Study

Purpose The purpose of this study was to determine perceived cognitive functioning, fatigue, depression and general well-being among women before and after the initiation of chemotherapy for breast cancer compared to a sample of healthy women. Method This descriptive, repeated measures study compared women receiving chemotherapy and healthy women. Women completed measures of quality of life, fatigue, cognitive changes and depression. Results Before chemotherapy, women with cancer reported more fatigue and depression than healthy women. After chemotherapy, women with cancer reported decreased cognitive functioning accompanied by more fatigue and depressive symptoms than healthy women. Conclusion This study is one of the first to use multiple symptom measures before and after starting chemotherapy. Understanding cognitive changes and related symptoms that occur before and during chemotherapy for breast cancer is the first step toward helping women cope with changes that occur with breast cancer treatment

A New Low-Mass Eclipsing Binary from SDSS-II

We present observations of a new low-mass double-lined eclipsing binary system discovered using repeat observations of the celestial equator from the Sloan Digital Sky Survey II. Using near-infrared photometry and optical spectroscopy we have measured the properties of this short-period [P=0.407037(14) d] system and its two components. We find the following parameters for the two components: M_1=0.272+/-0.020 M_sun, R_1=0.268+/-0.010 R_sun, M_2=0.240+/-0.022 M_sun, R_2=0.248+/-0.0090 R_sun, T_1=3320+/-130 K, T_2=3300+/-130 K. The masses and radii of the two components of this system agree well with theoretical expectations based on models of low-mass stars, within the admittedly large errors. Future synoptic surveys like Pan-STARRS and LSST will produce a wealth of information about low-mass eclipsing systems and should make it possible, with an increased reliance on follow-up observations, to detect many systems with low-mass and sub-stellar companions. With the large numbers of objects for which these surveys will produce high-quality photometry, we suggest that it becomes possible to identify such systems even with sparse time sampling and a relatively small number of individual observations.Comment: 15 Pages, 9 Figures, 6 Tables. Replaced with version accepted to Ap