Interlocked feedback loops contribute to the robustness of the Neurospora circadian clock

Interlocked feedback loops may represent a common feature among the regulatory systems controlling circadian rhythms. The Neurospora circadian feedback loops involve white collar-1 (wc-1), wc-2, and frequency (frq) genes. We show that WC-1 and WC-2 proteins activate the transcription of frq gene, whereas FRQ protein plays dual roles: repressing its own transcription, probably by interacting with the WC-1/WC-2 complex, and activating the expression of both WC proteins. Thus, they form two interlocked feedback loops: one negative and one positive. We establish the physiological significance of the interlocked positive feedback loops by showing that the levels of WC-1 and WC-2 determine the robustness and stability of the clock. Our data demonstrate that with WC-1 being the limiting factor in the WC-1/WC-2 complex, the greater the levels of WC-1 and WC-2, the higher the level of the FRQ oscillation and the more robust the overt rhythms. Our data also show that, despite considerable changes in the levels of WC-1, WC-2, and FRQ, the period of the clock has been limited to a small range, suggesting that the interlocked circadian feedback loops are also important for determining the circadian period length of the clock.

A chimeric light-regulated amino acid transport system allows the isolation of blue light regulator (blr) mutants of Neurospora crassa.

We have developed a system for the isolation of Neurospora crassa mutants that shows altered responses to blue light. To this end we have used the light-regulated promoter of the albino-3 gene fused to the neutral amino acid permease gene mtr. The product of the mtr gene is required for the uptake of neutral aliphatic and aromatic amino acids, as well as toxic analogs such as p-flurophenylalanine or 4-methyltryptophan. mtr trp-2-carrying cells were transformed with the al-3 promoter-mtr wild-type gene (al-3p-mtr+) to obtain a strain with a light-regulated tryptophan uptake. This strain is sensitive to p-fluorophenylalanine when grown under illumination and resistant when grown in the dark. UV mutagenesis of the al-3p-mtr(+)-carrying strain allowed us to isolate two mutant strains, BLR-1 and BLR-2 (blue light regulator), that are light-resistant to p-fluorophenylalanine and have lost the ability to grow on tryptophan. These two strains have a pale-orange phenotype and show down-regulation of all the photoregulated genes tested (al-3, al-1, con-8, and con-10). Mutations in the BLR strains are not allelic with white collar 1 or white collar 2, regulatory genes that are also involved in the response to blue light.

Desigualdades de género en salud laboral en España

Objetivos: Analizar las desigualdades de género en las condiciones de empleo, trabajo, conciliación de la vida laboral y familiar, y en los problemas de salud relacionados con el trabajo en una muestra de la población ocupada en España en el año 2007 teniendo en cuenta la clase social y el sector de actividad. Métodos: Las desigualdades de género se analizaron mediante 25 indicadores en los 11.054 trabajadores entrevistados en la VI Encuesta Nacional de Condiciones de Trabajo. Se calcularon las odds ratio (OR) y sus intervalos de confianza del 95% (IC95%) mediante modelos de regresión logística multivariados, estratificando por clase social ocupacional y sector de actividad. Resultados: Más mujeres que hombres trabajaban sin contrato (OR = 1,83; IC95%: 1,51-2,21), con alto esfuerzo o baja recompensa (1,14:1,05-1,25) y sufriendo acoso sexual (2,85:1,75-4,62), discriminación (1,60:1,26-2,03) y más dolores osteomusculares (1,38:1,19-1,59). Más hombres que mujeres trabajaban a turnos (0,86:0,79-0,94), con altos niveles de ruido (0,34:0,30-0,40), altas exigencias físicas (0,58:0,54-0,63) y sufriendo más lesiones por accidentes de trabajo (0,67:0,59-0,76). Las trabajadoras no manuales mostraron trabajar con un contrato temporal (1,34:1,09-1,63), expuestas a más riesgos psicosociales y sufriendo mayor discriminación (2,47:1,49-4,09) y enfermedades profesionales (1,91:1,28-2,83). En el sector de la industria las desigualdades de género fueron más marcadas. Conclusiones: En España existen importantes desigualdades de género en las condiciones de empleo, trabajo y en los problemas de salud relacionados con el trabajo, que se ven influenciadas por la clase social y el sector de actividad, y que sería necesario tener en consideración en las políticas públicas de salud laboral.

Social determinants of self-perceived discrimination in Spain

Objectives: To analyse the association between self-perceived discrimination and social determinants (social class, gender, country of origin) in Spain, and further to describe contextual factors which contribute to self-perceived discrimination. Methods: Cross-sectional design using data from the Spanish National Health Survey (2006). The dependent variable was self-perceived discrimination, and independent and stratifying variables were sociodemographic characteristics (e.g. sex, social class, country of origin, educational level). Logistic regression was used. Results: The prevalence of self-perceived discrimination was 4.2% for men and 6.3% for women. The likelihood of self-perceived discrimination was higher in people who originated from low-income countries: men, odds ratio (OR) 5.59 [95% confidence interval (CI) 4.55–6.87]; women, OR 4.06 (95% CI 3.42–4.83). Women were more likely to report self-perceived discrimination by their partner at home than men [OR 8.35 (95% CI 4.70–14.84)]. The likelihood of self-perceived discrimination when seeking work was higher among people who originated from low-income countries than their Spanish counterparts: men, OR 13.65 (95% CI 9.62–19.35); women, OR 10.64 (95% CI 8.31–13.62). In comparison with Spaniards, male white-collar workers who originated from low-income countries [OR 11.93 (95% CI 8.26–17.23)] and female blue-collar workers who originated from low-income countries (OR 1.6 (95% CI 1.08–2.39)] reported higher levels of self-perceived discrimination. Conclusions: Self-perceived discrimination is distributed unevenly in Spain and interacts with social inequalities. This particularly affects women and immigrants.

National survey of professional, administrative, technical, and clerical pay /

Description based on: 1980.

Office and technical workers fact book.

Mode of access: Internet.

Report of the United States delegation to a meeting of the International Labor Organization [at] the fifth session of the Advisory Committee on Salaried Employees and Professional Workers, Cologne, Germany, Nov. 23-Dec. 4, 1959.

Cover title.

Office workers : salaries, hours of work, supplementary benefits, New York, N. Y., January-February 1948.

Cover title.

Leisure at work in Britain, West Germany, France and Japan : a cross-cultural comparative study

The aim of this thesis was to investigate the impact of changing values and attitudes toward work and the workplace in Britain, West Germany, France and Japan. A cross-national approach was adopted in order to gain a better understanding of differences and similarities in behaviour and to identify aspects specific to each society. Although the relationship between work and leisure has been thoroughly examined and there is a growing body of literature on changes in the values associated with these two phenomena, little research has been carried out into leisure at work. Studies of work time have tended to consider it as a homogeneous block, whereas recent research suggests that more attention should be devoted to unravelling the multiple uses of time at the workplace. The present study sought to review and analyse this new approach to the study of work time, and special attention is devoted to an examination of definitions of leisure, recreation, free time and work within the context of the workplace. The cross-cultural comparative approach gave rise to several problems due to the number of countries involved and the unusual combination of factors being investigated. The main difficulties were differences in the amount and quality of literature available, the non-comparability of existing data, definitions of concepts and socio-linguistic terms, and problems over access to organizations for fieldwork. Much of the literature generalizes about patterns of behaviour and few authors isolate factors specific to particular societies. In this thesis new empirical work is therefore used to ascertain the extent to which generalizations can be made from the literature and characteristics peculiar to each of the four countries identified. White-collar employees in large, broadly comparable companies were studied using identical questionnaires in the appropriate language. Respondents selected were men and women, aged between 20-65 years and either managers or non-managers. Patterns of leisure at work were found to be broadly similar in the national contexts, but with the Japanese and the West Germans experiencing the least leisure at work, and the British and the French perceiving the most. The general trend seems to be toward convergence of attitudes regarding leisure at work in the four countries. Explanations for variations in practice were sought within the wider societal contexts of each country.

Trade union policy and new technology: the Civil and Public Services Association

The introduction of a micro-electronic based technology to the workplace has had a far reaching and widespread effect on the numbers and content of jobs. The importance of the implications of new technology were recognised by the trade unions, leading to a plethora of advice and literature in the late 70s and early 80s, notably the TUC 'Technology and Employment ' report. However, studies into the union response have consistently found an overall lack of influence by unions in the introduction of technology. Whilst the advent of new technology has coincided with an industrial relations climate of unprecedented hostility to union activity in the post-war period, there are structural weaknesses in unions in coming to terms with the process of technological change. In particular was the identification of a lack of suitable technological expertise. Addressing itself to this perceived weakness of the union response, this thesis is the outcome of a collaborative project between a national union and an academic institution. The thesis is based on detailed case studies concerning technology bargaining in the Civil Service and the response of the Civil and Public Services Associations (CPSA), the union that represents lower grade white collar civil servants. It is demonstrated that the application of expertise to union negotiators is insufficient on its own to extend union influence and that for unions to effectively come to terms with technology and influence its development requires a re-assessment across all spheres of union activity. It is suggested that this has repercussions for not only the internal organisation and quality of union policy formation and the extent, form and nature of collective bargaining with employer representatives, but also in the relationship with consumer and interest groups outside the traditional collective bargaining forum. Three policy options are developed in the thesis with the 'adversarial' and 'co~operative' options representing the more traditional reactive and passive forms of involvement. These are contrasted with an 'independent participative' form of involvement which was a 'pro-active' policy option and utilised the expertise of the Author in the CPSA's response to technological change.

Outsourcing in Ireland:a literature review, survey and case study perspective

Outsourcing, or offshoring as it is now known, has been around for many decades. In the beginning it was only the very peripheral activities that were blue-collar (lower skilled) work outsourced, but this is now all changing with the outsourcing of white-collar jobs. Historically outsourcing was used when organisation could not perform to world-class excellence in all sectors of the organisation due to incompetence of staff and/or management, lack of capacity, financial pressures, and/or technological pressures. The research currently underway is initially focusing on a literature review of current outsourcing applications in the market place and what impact outsourcing has on business performance. This paper will present the findings of the initial literature review. It will also discuss the methodology being followed to explore the Irish Industrial Sector.

Outsourcing: a Theoretical Viewpoint

Outsourcing or offshoring as it is now known has been around for many decades. In the beginning, it was only very peripheral activities that were outsourced, i.e. blue-collar (lower skilled) work but this is now all changing with the outsourcing of white-collar jobs. The digital revolution, the falling costs of transport and telecom costs and the opening up of the global economy helped the outsourcing market. For companies going down or contemplating the road of outsourcing there are both potential benefits and challenges, for example, the type of outsourcing they want to get involved in, and the country they want to outsource to. Outsourcing can potentially happen anywhere in the world where the costs are lower and the quality higher. The main places that have been used for outsourcing have been India, China, Ireland, South-East Asia, Russia, Mexico and the Czech Republic. The research currently underway is initially focusing on a literature review of current outsourcing applications in the market place. From this literature review, a questionnaire is being developed to assess the impact Outsourcing has on businesses. This research focuses on the Irish Market place.

Three essays on entrepreneurial entry, serial entrepreneurship, and labor turnover

This study explores two important aspects of entrepreneurship — liquidity constraints and serial entrepreneurs, with an additional analysis of occupational choice among wage workers. In the first essay, I revisit the question of whether entrepreneurs face liquidity constraints in business formation. The principle challenge is that wealth is correlated with unobserved ability, and adequate instruments are often difficult to identify. This paper uses the son's birth order as an instrument for household wealth. I exploit the data available in the Korean Labor and Income Panel Study, and find evidence of liquidity constraints associated with self-employment in South Korea. The second essay develops and tests a model that explains entry into serial entrepreneurship and the performance of serial entrepreneurs as the result of selection on innate ability. The model supposes that agents establish businesses with imperfect information about their entrepreneurial ability and the profitability of business ideas. Agents continually observe signals with which they update their beliefs, and this process eventually determines their next business choice. Selection on ability induces a positive correlation between entrepreneurial experience (measured by previous business earnings and founding experience) and serial business formation, as well as its subsequent performance. The predictions in the model are tested using panel data from the NLSY79. The analysis permits a distinction to be made between selection on innate ability and learning by doing. Motivated by previous empirical findings that white-collar workers had higher turnover rates than blue-collar workers during firm expansion, the third essay further examines job turnover among workers with or without specific skills. I present a search-matching model, which predicts that when firm growth is driven by technological advance, workers whose skills are specific to the obsolete technology show a higher tendency to separate from their jobs. This hypothesis is tested with data from the PSID. I find supportive evidence that in the context of technological change, having an occupation requiring specific skills, such as computer specialists or engineers, increases the odds of job separation by nearly eight percent. ^

The impact of migration and intergenerational changes on the Cuban family in the United States

This study examines changes in the Cuban family in the United States produced by time, migration, and the rise of new generations. The thesis will use a data set extracted from the 5% Public Use Microdata Series (PUMS) of the U.S. Decennial Census of Population for the years 1970, 1980 and 1990. Contingency table analysis and comparison of means were used to examine various family-related variables. The analysis points to changes in the traditional Cuban family towards less traditional family arrangements. The multigenerational feature of the Cuban household has diminished as the elderly have become independent and are more likely to be living on their own. Although female labor participation remains high, the occupational patterns of the first generation of Cuban women have diversified and a new trend has emerged for the second generation. The second generation of Cuban women demonstrates a strong inclination for white-collar occupations. Fertility rates remain low.