Exact algorithms for scheduling programs with shared tasks

We study a scheduling problem where the jobs we have to perform are composed of one or more tasks. If two jobs sharing a non-empty subset of tasks are scheduled on the same machine, then these shared tasks have to be performed only once. This kind of problem is known in the literature under the names of VM-PACKING or PAGINATION. Our objective is to schedule a set of these objects on two parallel identical machines, with the aim of minimizing the makespan. This problem is NP-complete as an extension of the PARTITION problem. In this paper we present three exact algorithms with worst-case time-complexity guarantees, by exploring different branching techniques. Our first algorithm focuses on the relation between jobs sharing one or more symbols in common, whereas the two other algorithms branches on the shared symbols.

     

The role of experts in forming family policy under an adversarial subsystem in the Czech Republic

This article analyzes the interplay between policymakers and scientists in developing the Family Policy Plan for the Czech Republic in 2017. As former members of the government commission that developed the plan, we base the article on participatory observation. When we joined the commission, a ‘window of opportunity’ had opened as the country for the first time ever had feminist-friendly minister and vice-minister of labour and social affairs. We explain why due to the inter- and intra-party dynamics, the parental leave reform to introduce ‘daddy months’ failed. We argue an adversarial subsystem existed in that the three coalition partners disagreed on the reform. According to Ingold and Gschwend (2014), under such circumstances, scientists play a strategic role, especially if there is unity among them. However, although there was basic unity among the scientists in the commission, the coalition partners at the governing level were able to block or water down the reform proposal under the study.     

Returns to Education during the Reform of State‐owned Enterprises in Hunan,People’s Republic of China

The objective of this paper is to analyse the impact of education on personal earnings during the reform of state‐owned enterprises, comparing 1995 with 1998 in Hunan, China, using the Mincerian earnings equation method. The results show that the rates of return to education increased, indicating that human capital has been better rewarded as the reforms of the Chinese economic structure have progressed. Moreover, the findings show that primary education receives the highest returns, followed by tertiary education. Middle school education obtains the lowest rewards, reflecting the effects of the reform of state‐owned enterprises on middle school graduates on whom the unemployment impact of this change has been the greatest.     

Influence of habitat type and distance from source area on bird taxonomic and functional diversity in a Neotropical megacity

The Neotropical region has been subjected to massive urbanization, which poses high risks for some global biodiversity hotspots and losses of ecosystem functions and services. In this study, we investigate how distance from large patches of native forests (source areas) and vegetation (green)/and infrastructure (gray) characteristics affect bird species richness and functional diversity in São Paulo megacity, southeastern Brazil. We analyzed the effects of source areas and green/gray characteristics on species richness and functional diversity (richness, evenness, and divergence) indices. We detected 231 bird species, and our data confirmed our predictions: (1) bird species richness in urbanized habitats was found to be (~?50–85%) lower than in source habitats; (2) species richness and trait composition significantly decreased as the distance from the source area increased, while functional richness was not affected by this metric; and (3) shrub and herbaceous covers and maximum height of trees were positively correlated with species richness and unique functional traits regarding habitat, diet, foraging and nesting strata and dispersal ability of birds in the forest-urban matrix. The number of buildings was negatively correlated with bird species richness and functional richness. Maximum height of buildings caused dramatic declines in functional evenness. Functional divergence was notably lower in sites with high shrub cover. Our study stresses the complexity of vegetation embedded in large Neotropical urban settlements and the need to maintain large protected areas surrounding megacities to mitigate the impacts of urbanization on birds.

     

Free time,gender and the pandemic: An exploration of children's daily routines in the times of COVID-19 in Chile

This article discusses the differentiation by gender displayed by children between 8 and 12 years old on how they used their free time during the COVID-19 pandemic in Chile. This study had a qualitative approach, where 43 in-depth interviews were conducted with children from three different regions of the country, using participatory photo-elicitation as the central tool. The main results of the study show a configuration of free time based on gender stereotypes, showing that boys are the ones who most adhere to such stereotypes, triggering a crisis in the identity construction of masculinities during childhood. The study also suggests that socioeconomic and territorial differences between children configures different experiences of the use of free time.     

Disorganized attachment,mentalization and dissociation in context of childhood trauma: Implications for depressive symptoms

Extensive evidence indicates that adults with experience of childhood trauma and disorganised attachment are at a higher risk of suffering from depressive symptoms, while at the same time dissociation and mentalisation are very important risk and protective factors in this relation. Although mentalisation and dissociation are mentioned as potential mediators of this relationship, very few studies have analysed the mutual relations between these variables. Bearing in mind the importance of creating more specific and effective ways for dealing with depression, especially within vulnerable groups such as the traumatised, the aim of this research is to examine a serial mediation model in which disorganisation is modelled as effecting a decrease in mentalisation, in turn lead to dissociation, thereby resulting in depressive symptoms. Adult respondents (N = 153) with a history of interpersonal childhood trauma were selected from a larger geographical cluster sample from the general population of Serbia. The respondents filled in a battery of instruments, including The Childhood Traumatic Events Scale, Relationship Questionnaire – CV, Patient Health Questionnaire, Short Scale for the Assessment of Stress-Related Dissociation Symptomatology and the Mentalisation Scale. Our findings suggest that disorganisation has an effect on depression by leading to a decrease in the ability to mentalise, which further triggers dissociation, resulting in depressive symptoms as a final consequence (estimated indirect effect = 0.014, 95 percent CI = 0.005 to 0.026). Additionally, the specific indirect effect involving dissociation as the sole mediator was also significant (estimated indirect effect = 0.058, 95 percent CI = 0.030 to 0.091). Targeting dissociative symptoms in the treatment in patients struggling with depression aftermath of traumatic experience could gain a great benefit for recognition and selection of more adequate treatment strategies.