The pull evolution: from Kanban to customised token-based systems

This work formalises a new approach for material flow control, i.e. the so-called customised token-based systems (CTBS). This approach represents a natural evolution from classical pull systems, such as Kanban. The article first describes the flow of materials (orders or tasks) from a management point of view, and discusses exact and approximate approaches to tackle the problem. The origin of Customised Production Control systems is explained, as well as the main advantages: high degree of generalisation, enhancement of the space of solutions and adaptation to the manufacturing environment. Next, we propose a method based on cross-entropy for the optimisation of CTBS. The computational experience carried out in a number of scenarios shows the CTBS to be profitable. Furthermore, the resulting control mechanisms seem to be relatively easy to implement in real-manufacturing environments.     

Access to Mental Health Services: The Struggle of Poverty Affected Urban Children of Color

It is estimated that, in the United States, one in ten children and adolescents suffer from illness severe enough to cause some level of psychosocial dysfunction. Urban children, and in particular low-income children of color, are at greater risk of developing mental health problems, and are less likely to receive effective child mental health services. Prompt and effective access to mental health services by urban children of color is a critical direct practice and social policy concern. This article provides an overview of significant barriers to mental health care experienced by poverty affected urban children of color and their families. It also addresses a broad range of practice and policy issues that need to be raised in order to ensure competent delivery of mental health services for children living in urban environments. The role of social work in assisting poor urban children of color to access and benefit from mental health services is stressed. Manny John González, D.S.W., is an Assistant Professor of Social Work at Fordham University Graduate School of Social Service.     

The Alligator Woman's Tale: Remembering Nicaragua's “First Self-Declared Lesbian”

Carmen Aguirre (1931–1971) was a young woman who lived as a self-made man in the 1960s under the brutal, yet populist, right-wing Somoza dictatorship in Nicaragua. Carmen was known as Carmelo or la Caimana (the alligator woman). This article sheds light not only on la Caimana's life, but on how he is remembered today in Nicaragua. It addresses dynamics of Nicaragua's sexual past, present, and future, as well as theoretical questions dealing with identity, sex, and politics.     

Medical and Scientific Conferences as Sites of Sociological Interest: A Review of the Field

Conferences play a pivotal role in the production and circulation of knowledge and in shaping and establishing academic and professional disciplines. As collective events, they facilitate intense moments of interaction where scientific and medical knowledge can be observed in the making. This paper calls attention to conferences as fascinating sites for sociologists of science, technology and medicine. By bringing together authors who look at conferences from different areas within the social sciences and using a variety of data gathering methods, this paper provides a comprehensive introduction to the field of conference studies and hopes to inspire greater reflection about the nature of conferences and their potential within research.     

When stressors make you work: Mechanisms linking challenge stressors to performance

Based on previous empirical findings, “challenge stressors” (Cavanaugh, Boswell, Roehling, & Bouderau, 2000 Cavanaugh, M. A., Boswell, W. R., Roehling, M. V., & Boudreau, J. W. (2000). An empirical examination of self-reported work stress among U.S. managers. Journal of Applied Psychology, 85, 65–74. doi:10.1037/0021-9010.85.1.65[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]; Lepine, Podsakoff, & Lepine, 2005 LePine, J. A., Podsakoff, N. P., & LePine, M. A. (2005). A meta-analytic test of the challenge stressor hindrance stressor framework: An explanation for inconsistent relationships among stressors and performance. Academy of Management Journal, 48, 764–775. doi: 10.5465/AMJ.2005.18803921[Crossref], [Web of Science ®] , [Google Scholar]), such as the amount and scope of responsibility, can be loosely considered as “good stressors” that are consistently and positively related to job satisfaction and performance. We introduce the role of appraisal to further examine how challenge stressors are connected to performance. Structural equation modelling analyses using an applied sample of 284 employee–supervisor dyads showed that affective commitment to the organization mediated the relationship between both opportunity and threat appraisal and performance (in-role and extra-role). The mediating role of increased psychosomatic distress was supported only for the relationship between threat appraisal and in-role performance. The findings indicate the importance of taking into account the actual appraisal of “challenge stressors”, as it carries implications for performance, and reveals the key role of affective commitment and induced distress mechanisms in this relationship. In conclusion, “challenge stressors” are not always positively related to performance, but only when they are perceived as opportunities.     

Mindful Ethics: Comments on Informant-Centered Practices in Sociological Research

In this article, I introduce the concept of “mindful ethics” to describe my experiences as a feminist qualitative researcher who has confronted ethical dilemmas in my sexuality research. Mindful ethics is informed theoretically by mindful inquiry, grounded theory, ethics in practice, and ethically important moments. Mindful ethics has been useful in dealing with ethical considerations throughout all stages of my sexuality research. Shifting my attention to the takenfor-granted social contexts and circumstances surrounding informants’ life experiences has helped me deal with ethical concerns that otherwise may have resulted in harm to informants.     

Parametric Bayesian inference for Y-linked two-sex branching models

A Y-linked two-sex branching process with blind choice is a suitable model for analyzing the evolution of the number of carriers of two alleles of a Y-linked gene in a two-sex monogamous population where each female chooses her partner from among the male population without caring about his type (i.e., the allele he carries). This work focuses on the development of Bayesian inference for this model, considering a parametric framework with the reproduction laws belonging to the power series family of distributions. A sample is considered given by the observation of the total number of females and males (regardless of their types) up to some generation as well as the number of each type of male in the last generation. Using a simulation method based on the Gibbs sampler, we approximate the posterior distributions of the main parameters of this model. The accuracy of the procedure based on this sample is illustrated by way of a simulated example.     

Does higher income equal higher levels of happiness in every society? The case of the Mayan people

Guardiola J, González‐Gómez F, García‐Rubio MA, Lendechy‐Grajales Á. Does higher income equal higher levels of happiness in every society? The case of the Mayan people This study analysed happiness and several domains of life of Mayan people in the poor rural areas of Yucatan, Mexico. Using a sample of 373 households, we examined the influence of income on happiness and its domains, obtaining results that lend support to the ‘paradox of happy peasants and miserable millionaires’. According to the results, income influences happiness among the Mayan people, as do material domains and health, but income does not influence the domains related to intangible feelings and public goods. A number of reasons, such as a lack of a means for comparison, close contact with nature, adaptation to deprivation, general material improvements compared with the past, low aspirations and a Mayan culture that is devoted to solidarity and enjoyment of social relationships, could explain why the sample population reported high levels of happiness. Although the Mayans' level of happiness is high, their situation nevertheless requires political attention.     

Influence diagnostics in the tobit censored response model

In this article, we develop influence diagnostic tools for the tobit model. Specifically, we discuss global influence methods based on the Cook distance and residuals with envelopes, and total and conformal local influence techniques. In order to analyze the sensitivity of the maximum likelihood estimators of the parameters of the model to small perturbations on the assumptions of the model and/or data, we consider several perturbation schemes, such as case-weight and response perturbations. Finally, we illustrate the developed methodology by means of a real data set.