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The decay p p ( at rest ) → K L o K ± π ∓ π o , studied on a sample of more than 14000 events, is found to proceed dominantly via two-body channels containing resonances with open strangeness. Contributions from K 1 (1270) K and K 1 (1400) K , branching into the successive K1-decay modes, and from K ∗ K ∗ , K ∗ ( K π) s and (Kπ) s ( K π) s are extracted by means of a partial-wave analysis which accounts well for the data and also allows a search for weak contributions from other (Kππ) and from ( K K π ) resonances. Striking asymmetries between the charged and the neutral kaonic resonances give evidence for interfering isospin 0 and 1 annihilation amplitudes.

The annihilation channel p p →K + K − π 0 in liquid hydrogen at rest has been studied with the Crystal Barrel detector at LEAR. The measured branching ratio is: BR ( p p → K + K − π 0 )=(2.37±0.15)×10 −3 . A partial wave analysis shows that this reaction is dominated by the π (K K ) S , K K ∗ (892) and π φ (1020) intermediate states. Weak signals are observed for π a 2 (1320), π f 2 (1270), π f 2 ′(1525) and K(Kπ) S . A satisfactory description of the Dalitz plot requires the introduction of π (K K ) P intermediate states with at least one pole.

We have measured the branching ratio for the radiative decay ω → ηγ with ω mesons produced in antiproton-proton annihilation at rest into π0ω and ηω. Taking into account ϱ - ω mixing we find a branching ratio B(ω → ηγ) = (6.6 ± 1.7) × 10−4, in accord with the constructive interference solution in other experiments. The upper-limit for the direct radiative decay ω → 3γ is 1.9 × 10−4 at 95% confidence level.

The π + π − invariant mass distribution produced in p p annihilation at rest and recoiling against η mesons exhibits large interference between the amplitudes for ϱη and ωη production. The interference can be quantitatively described within the framework of ϱ-ω interference. We find full coherence between the ϱω-ωη production amplitudes and a vanishing relative production phase. The implications of this result for p p annihilation dynamics are discussed.

Processes and measures of convergence for population matrices are considered based on additive norms other than the eigen-norm. Prior results on natural and spectral converges measures for population matrices [1] are shown to be partly valid for an arbitrarily weighted norm termed the W-norm. Special cases of imprimitive population matrices are analyzed for applicability of results on stability and convergence measures. These include the truncated case that includes post-fertile age groups and periodic cases, i.e., ones in which fertility occurs periodically across age groups.

A partial wave analysis of pp → π0π0η′ has been performed using the η′ → π0π0η and η′ → γγ decay modes. The data are dominated by an η′ recoiling against the (ππ) S-wave. In addition, α2 (1320) → η′π0 is needed. There is evidence for contributions from α0(1450) → η′π0. The branching ratio of α0(1450) → η′π0 with respect to ηπ0 is consistent with the prediction of SU(3).

There have been numerous studies which evaluate the impact of NAFTA on employment, immigration, the environment and other areas of concern. However, one key area has received little attention: the linkage between the potential effect of growth and change in the Mexican labor force and the presence of a North American Free Trade Zone. The linkage is in both directions. The success or failure of NAFTA will be fundamentally affected by the size, age, education and job skills of the Mexican labor force. Moreover, the Mexican labor force will be affected by NAFTA. In particular, the number, type and location of job opportunities over the next several decades will be determined, at least partially, by the success or failure of NAFTA. This article contains an analysis of projections of the Mexican labor force in relation to the recently enacted NAFTA agreement. We begin with a discussion of the NAFTA agreement, concentrating on its labor force implications in Mexico and the U.S. During this discussion, we pay particular attention to the implications of our analysis on the border region. We then present the projections of the Mexican labor force, looking at alternative assumptions for fertility, international migration and economic activity rates. While our primary focus is on the Mexican labor force, projections of the U.S. labor force need to be considered also. Finally, the policy implications of the projected labor force changes under alternative NAFTA scenarios will be considered.

This article has the objectives to discuss the background for the two special issues of International Journal of e-Collaboration on electronic collaboration in organizations, examine four theoretical frameworks with particular regard to their relevance to the content in the articles in the special issues, and summarize each of the nine articles in these issues. The articles in the special issues are diverse in conceptual theory, units of analysis, research methods, and levels of collaboration. Units of analysis span from the individual, virtual team, company to the dyadic relationship between firms. Electronic collaboration is studied in locales including Austria, Korea, the Netherlands, Switzerland, and the United States. The diversity extends knowledge within varied realms of the electronic collaboration field. This introductory article offers an overall framework for these two special issues to help readers and potential authors see how the studies relate to one another and to the overall body of knowledge.

This chapter examines the success factors for industry-university collaboration through IS industry boards. Based on an in-depth case of industry-academic collaboration in Mexico, the chapter addresses the following research questions: What are the critical success factors for achieving good outcomes from an IS industry board? What factors impede the achievement of good outcomes from such a board in a developing nation? What factors are distinctive and serve to differentiate IS industry boards of developing nations from those of advanced ones? In the case study, the IS industry board enhanced the IS academic program’s curriculum, the university’s computer labs, the student internship program, and faculty training. This case demonstrates that the critical success factors for the IS industry board were top management support, the department chair’s interpersonal skills, board member selection, proper board management, and appropriate university policies regarding industry-university collaboration. The experiences of developing and advanced nations for such boards are mostly similar, but differ due to lack of tenure track careers for IS faculty in the developing nation under study.

This chapter identifies the technology and non-technology factors that companies consider important in deciding to adopt and deploy wireless devices designed for mobile telephony and information services, the extent of current use of cell phones, the extent of existing utilization and/or planning for Web-enabled cell phone use, the constraining factors in their deployment decisions, how such decisions are made, and the practical technology implications for decision-making, including beyond 3G. This chapter seeks to help decision makers by shedding light on the adoption process. The conceptual model combines the TAM and innovation adoption/diffusion models, adding the factors of security, cost, reliability, digital standards/regulatory environment, technology product suitability, and future Web connectivity. Case study methodology is utilized for five manufacturing and technology firms. A key finding is that the most important technology decision factors are security, reliability, and Web connectivity. Although the current uses are dominated by voice, Web-enabled capability dominates future decision-making.

The standard human population pyramid contains only current information; it is often inadequate when making comparisons of different countries or years. A graphic computer program superimposes current population, life table survivor ships, stable population, and past population projected up to the present. Fertility, health conditions, migration, and demographic transition stage are better revealed by this expanded graph form. A time series of the modified pyramids reveals detailed age-specific trends for a country or region. With ’minor modifications the computer program is applicable to all machines with a Fortran IV compiler.

This paper presents a model of governmental, investment, social, and economic factors that influence technological utilization for 110 countries. Structural equation modeling is applied to conceptualize and test the model. This model uses latent and observable variables and the application tests the hypothesis that technology use can be accounted for in a multidimensional model composed of four factors: Government Support/Legal Framework/Openness, Investment in Business and Technology, Socioeconomic Level, and Technology Utilization. Findings indicate a critical pathway of influences between the factors of government support/legal framework/openness, socioeconomic level, and technology utilization. The results are important because they model complex path relationships between factors identified in the literature, but not previously available for SEM analysis. The paper suggests policy steps for national governments of developed and developing nations especially for policies stressing investment in ICT, strengthening of R&D, societal openness, a strong legal system, prioritization of ICT, and betterment of education.

This study examines state migration patterns to Baja California for most of the twentieth century. Methods of analysis include computerized mapping and regression. Findings indicate that, in spite of very rapid population growth in Baja California, the geographic distribution for origin states of migration to Baja remained consistent over eighty years of censuses from 1900 to 1980. Furthermore, there is strong consistency in the determinants of migration over the eighty years. There is ample indication that the intervening distance/obstacles hypothesis is a major factor in explaining migration patterns in Mexico, especially to the border region. Also, an economic opportunity model of migration explains at least part of the two major, contrasting migration patterns that have historically occurred in Mexico during this century, one to the Federal District and the other to the U.S. borderlands area, especially Baja California (for a contrasting view, see Davis 1981). This article examines the concepts of intervening distance/obstacles as opposed to economic opportunities influences upon migration (Fukurai et al. 1987a, Greenwood et al. 1981, King 1978, Lowly 1966, Rogers 1968, Whetten and Burnight 1956, Zipf 1946).

This paper examined effects of various socioeconomic variables on fertility for selected samples of municipios in the border region of Mexico. A theoretical model of Mexican borderlands fertility is mostly confirmed by regression analysis of 1980 census data. An improved model is suggested. The major results indicate that literacy is a major factor influencing the reduction in fertility male and female labor force participation have significant and opposite effects on fertility and unemployment generally lowers fertility. (SUMMARY IN SPA) (EXCERPT)

The research goal is to analyze the influence of education, workforce, economic, and policy factors on ICT usage, expenditure, and infrastructure in 67 countries. Findings indicate importance of R&D capacity, foreign direct investment, government prioritization of ICT, and math/science education. The findings that technology factors in poorer nations are more strongly associated with foreign direct investment and government initiatives contrast with this and other studies of more prosperous countries. The paper suggests policy steps that can be taken by national governments to foster the effective use of technology and reduce the digital divide including encouraging creative workforce, and emphasizing education, and fostering R&D.

Current investments in IS/IT are increasingly being deployed across multiple countries and world regions. In this connected global economy, crosssystem integration and collaboration technologies play essential roles and often determine the success or failure of IS/IT systems and projects. The intensive investigation for two decades of different aspects of IS/IT collaboration sets the context of this minitrack. The theme is the integration of people, systems, processes and infrastructure across organizations, borders, nations and world regions to enable productive teamwork toward accomplishing mutual goals. Until now, studies have been almost entirely focused on a single country or region.

This chapter examines the costs and benefits of geographic information systems (GIS). It focuses on the research questions of what components to include in GIS cost-benefit (C-B) analysis, what distinguishes GIS C-B analysis from non-spatial C-B analysis, what methods to use, and how to invest in GIS systems in order to obtain net payoffs over time. It categorizes costs and benefits of GISs. It considers the topics of systems analysis sub-steps in cost-benefit analysis, the feasibility decision, stakeholders and externalities, and the importance of timing and timeliness in investing in GIS and assessing payoffs. It examines the C-B aspects of a well-known GIS case study of Sears Roebuck’s delivery system. The literature on the value of investment in IT and productivity paradox is analyzed for its relevance to GIS investment. The major findings are, first, that the costs and benefits of a GIS can be estimated through modifications of standard non-spatial IS methods. Second, the key factors that differentiate GIS cost-benefit analysis from that of non-spatial IS are more extensive analyses of the costs of data acquisition, need to pro-rate the GIS costs and benefits for tightly linked combinations of GIS and other systems and technologies, and need for improved techniques to estimate the costs and benefits of the GIS’s visualization features.

This book contains state-of-the-art research studies on the concepts, theory, processes, and real world applications of geographical information systems (GIS) in business. Its chapters are authored by many of the leading experts in applying GIS and geospatial science to business. This book utilizes a wide variety of approaches and methodologies including conceptual theory development, research frameworks, quantitative and qualitative methods, case studies, systems design, DSS theory, and geospatial analysis combined with point-of-sale. Since relatively little research has been published on GIS in business, this volume is pioneering and is the principal compendium of the latest research in this area. Geographic Information Systems in Business will impact not only the underlying definitions, concepts, and theories of GIS in business and industry, but its practice as well.

This chapter examines the influence of socio-economic factors on the employment, payroll, and number of enterprises of three technology sectors for counties in California. Based on correlation and regression analyses, the results reveal that factors that are important correlates of technology sectors are professional/scientific/technical services, other services, and educational services, ethnicity, and college education. As a whole, the findings emphasize the importance of the association of socio-economic factors with the per capita magnitude of the technology sectors. This chapter suggests steps that can be taken by the state of California and its county and local governments to foster technology and reduce the digital divide.

This paper studies the technology factors that companies consider important in deciding to adopt and deploy wireless devices designed for mobile telephony and information services, the extent of current use of wireless cell phones, the extent of existing utilization and/or planning for Web-enabled cell phone use, the constraining factors in their deployment decisions, and how such decisions are made, and the practical technology implications for decision-making. Wireless cell phone technology has complex characteristics that often make the process of corporate adoption decisions difficult. This study seeks to shed light on this process to help decision makers. The conceptual model combines the TAM and innovation adoption/diffusion models, adding the factors of security, cost, reliability, digital standards, technology product suitability, and future Web connectivity. Case study methodology is utilized for five manufacturing and technology firms. A key finding is that the most important technology decision factors are security, reliability, and Web connectivity. Customer service was the most important non-technology factor. Although the current uses are dominated by voice, Web-enabled capability dominates future decision-making.

This paper examines the technological level of 74 counties in technologically advanced states in the United States at the end of the 1990s. The conceptual framework is that selected socioeconomic dimensions influence the level of technological development for advanced communities; i.e., technology does not develop by itself but in concert with pre-disposing characteristics of the environment. The influence of socioeconomic factors was studied through correlation and regression analysis. The findings reveal that, on a national basis, factors that are important across several technology sectors are college education, ethnicity, income, and federal grant funds. There are distinctive influences for high-tech counties in the “rust belt” versus the “sunbelt.” Taken together, the results highlight the association of socioeconomic factors with the per capita magnitude of the technology sectors. The findings are discussed relative to research literature and data collected, and policy and ethical implications are presented.

This chapter examines the relationship between IT expenditure and bank profitability, efficiency, productivity, and performance for Mexican banks. The principal research method is correlation analysis between IT expenditure and four bank performance indices: a profitability index that combines bank profits, income, operational cost, and financial cost; a performance index that includes credit and bank income market share; a productivity index consisting of the number of employees, branches, and managers; and an efficiency index that includes banks’ operational cost and income. The unit of analysis is the firm. The data are from the 18 banks comprising the Mexican banking industry from 1982–1992, when Mexico’s banks were owned by the federal government. The study’s interpretations are supported by interviews with four bank CIOs and a CEO, in office during the period. The main findings are that bank IT expenditure ratio is positively correlated to bank performance and productivity indices, whereas IT expenditure is not correlated with bank efficiency or profitability indices. There are fluctuations in the strength of correlation during the 11-year period, which are explained. The chapter results not only reject the productivity paradox but also provide insights to explain the paradox and IT contribution to the firm performance.

This paper analyzes the relationship between IT expenditure and the monetary value of organizations. Based on the case of the Mexican banking industry from 1982–1992, the paper’s hypotheses test the relationship between IT expenditure and the real and perceived market values of banks. Correlations are performed between annual IT expenditures for a 10 year period —when Mexico’s commercial banks were owned by the federal government— and bank selling prices, when the industry divestiture took place in 1992. The main findings are that IT spending has a positive impact on the value of the firm, when the value of the firm reflects the change of ownership or the control of the firm. Second, firms spending more on IT do not tend to reach higher selling prices. Other findings are presented. The model and its results are discussed in terms of the literature about value of investment and the productivity paradox.

This paper examines tourism in Mexico. The research questions concern the long term role of the Mexican federal government in developing and stimulating tourism, the extent of tourism dependency of Mexico on the United States, and the extent of regional differences in tourism within Mexico. The method is simple economic trend analysis. The research results are illustrated by a case study of a leading Mexican hotel chain. Findings are interpreted in terms of world systems theory. The paper shows that Mexican tourism has a large variety of forms and is tied to processes of globalization.

We report on a measurement of the branching ratio of the rare decay $\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\omega}}\ensuremath{\eta}\ensuremath{\gamma}$ relative to the well known decay $\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\omega}}{\ensuremath{\pi}}^{0}\ensuremath{\gamma}.$ The \ensuremath{\omega}'s are produced in $p\overline{p}\ensuremath{\rightarrow}\ensuremath{\eta}\ensuremath{\omega}$ and $p\overline{p}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}\ensuremath{\omega}.$ Eigenstate mixing and interference effects of the \ensuremath{\omega} and ${\ensuremath{\rho}}^{0}$ are taken into account, as well as coherent interference with the background. We find evidence for the non-resonant annihilation channel $B(p\overline{p}\ensuremath{\rightarrow}\ensuremath{\eta}\ensuremath{\eta}\ensuremath{\gamma})=(3.5\ifmmode\pm\else\textpm\fi{}1.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$ and limit the value of $B(\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\omega}}\ensuremath{\eta}\ensuremath{\gamma})$ to the range of $(0.7\mathrm{to}5.5)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ depending on the degree of coherence with the background.

The annihilation channel pp to K/sup +/K/sup -/ pi /sup 0/ in liquid hydrogen at rest has been studied with the Crystal Barrel detector at LEAR. The measured branching ratio is: BR(pp to K/sup +/K/sup -/ pi /sup 0/)=(2.37+or-0.15)*10/sup -3/. A partial wave analysis shows that this reaction is dominated by the pi (KK)/sub S/, KK*(892) and pi phi (1020) intermediate states. Weak signals are observed for pi a /sub 2/(1320), pi f/sub 2/(1270), pi f/sub 2/'(1525) and K(K pi )/sub S/. A satisfactory description of the Dalitz plot requires the introduction of pi (KK)/sub P/ intermediate states with at least one pole. (25 refs).

Mexico has a large and rapidly growing labor force. This paper projects the Mexican national labor force from 1980 to 2005, with varying assumptions of vital rates, economic activity, and international migration. Projections are also made for the urban and rural components of the Mexican population, assuming inter-component migration flows. Results indicate that the Mexican labor force will grow over the projection period at an average annual rate of 907,000 to 1,183,000 workers; will age slightly; and will have a much higher proportion female. Implications are discussed in terms of Mexican-U.S. migration, possible agreements on free trade, and global trends in workforce.

Staffing and managerial aspects of information systems in U. S. and Canadian art museums are examined. In general, art museums have non-professional computing staff, strong influences on the information systems function from outside the organization, and weak IS planning and control.Differences in the information systems environment of the charitable nonprofit versus the private sector are discussed. Based on the empirical results, modifications are made to the stage theory of end user computing to encompass a wider range of organizational and staffing types.

"This study examines the socioeconomic influence on migration frequency and transitory movements in four Mexican regions. The analysis is based on data gathered from the [Mexican Fertility Survey] 1976-1977, considering the influences of...education, occupation, literacy, place of residence and fertility. The methods used for this analysis were regression and logistic regression." Aspects considered include patterns of internal migration in Mexico, data sources, analysis of independent variables, migration experiences, and age effects. A comment by Carlos Brambila Paz is included (pp. 179-83). (SUMMARY IN ENG)

Although the ketogenic diet has existed for over 75 years, the exact mechanism of action is still unknown. In 1921, R.M. Wilder, MD theorized that the ketosis and acidosis resulting from minimal caloric intake produced an anticonvulsant effect. Since then, other investigators have validated the efficacy of the ketogenic diet and it has become a more common therapy for children with intractable seizures. The classic ketogenic diet involves an initial period of starvation that is followed by a diet consisting of a 3:1 or 4:1 ratio of fat grams to grams of carbohydrate and protein. The purpose of the fasting phase is to stimulate ketogenisis and to initiate hunger which will encourage the child to consume the diet. Studies have shown that during the fasting period, children can become hypoglycemic and too ketotic. At least one death has been reported during the fasting period of the diet. Medication levels are often unstable during fasting which can cause nausea, vomiting and irritability. For these reasons the ketogenic diet is started at our facility without the traditional fasting phase. On the morning of admission to the hospital, the child is allowed to eat his/her usual breakfast at home (omitting concentrated sweets). Upon admission to the hospital the child is fed ketogenic meals totaling l/3 rd of his/her total daily caloric diet goal. On day 2 of admission the child is fed 2/3rds of his/her total daily caloric goal. Full calories are provided on day 3. The medical charts of eleven consecutive children were reviewed and the highest level of urine ketones registered for each of the three days was recorded. Ketone levels were measured with urinalysis reagent strips and indicated as negative/trace/small/moderate/large. By day 3 100% ( 11) of the children had registered large urine ketones on 2 or more readings. We feel our practice has allowed a smooth transition to the ketogenic diet while minimizing hypoglycemia, excessive ketosis, nausea, and inpatient hospital days.

En este estudio se examina la influencia socioeconómica en la frecuencia de migración y movimientos transitorios en cuatro regiones de México. El análisis se basa en los datos colectados en la Encuesta Mexicana de Fecundidad 1976-1977, y considera la influencia de: educación, ocupación, alfabetización, lugar de residencia y fecundidad. Los métodos utilizados para el análisis son regresión y regresión logística. En la regresión logística las tres primeras transiciones de movimientos se separaron y se analizaron individualmente. Los resultados muestran una sucesión de influencias socioeconómicas dependiendo del estado de transición del movimiento. Para la transición 0–1 + el mayor efecto es el lugar de residencia; para la transición de 1–2 + es la ocupación de migrante; y para la transición de 2–3 + los efectos inconsistentes de edad y educación. Se muestran los efectos específicos de acuerdo con la edad y la región.

Aunque los autores reconocen que algunos aspectos del comentario son valiosos, discuten puntos que, en su opinión, son incorrectos.

The present study analyzes data on selected socioeconomic characteristics for the six states of Mexico on the U.S.-Mexico border utilizing data on the region's 272 municipios. A common definition of the Mexican borderlands, the one adopted in the present research, includes the six states of Baja California, Sonora, Chihuahua, Coahuila, Nuevo Leon, and Tamaulipas (Beegle et al. 1960; Stoddard et al. 1983; and Reich 1984). On occasion, researchers have modified the definition to encompass a seven state region, including the above states plus Baja California Sur (Stoddard 1983). The present analysis differs from all previous studies except Beegle et al. (1960) by analyzing all Mexican borderlands municipios. The data are first presented with descriptive statistics and computer mapping. Then, relationships among variables are examined at both regional and state levels.

A methodology is introduced to project the number of farm laborers displaced by reduction in agricultural land by geothermal energy development. For each geothermal area, the projection is based on estimates of land used for energy facilities and of land environmentally disrupted, on estimates of manpower per acre by crop type, and on estimates of alternative employment of farm laborers. Each area's projected farm labor force displacement per 100 megawatts is multiplied by the area's projected geothermal capacity. Results for Imperial County, California, indicate maximal farm laborer displacement in 25 years of 4.81 percent of the 1970 farm labor force. Assumption of slant drilling techniques reduces projected displacement. Distribution of crop types also significantly affects displacement. The methodology is transferable to other agricultural areas undergoing geothermal development.