Urban impacts on tropical island streams: Some key aspects influencing ecosystem response

Improving our understanding of the impacts of urbanization on tropical island streams is critical as urbanization becomes a dominant feature in tropical areas. Although the ??urban stream syndrome?? has been successful in summarizing urban impacts on streams, the response of some island streams is different to that expected. Here we review available information on urban impacts to tropical island streams and describe unique responses to urbanization. We identified three key aspects that play particularly important or unique roles in determining tropical-island stream integrity: biotic response to water pollution, movement barriers along the stream network, and altered geomorphology that results in habitat loss. As expected, water pollution negatively impacts stream ecosystems in tropical islands and in some regions impacts can be severe, as untreated wastewaters are directly discharged into streams. While aquatic insects show the expected responses to pollution, other native fauna (e.g., shrimps and fishes) appear to be less impacted by moderate levels of pollution. Movement barriers along the stream network are especially important as much of the tropical island fauna have diadromous (either amphidromous or catadromous) life histories. Most native freshwater mollusks, shrimps, and fishes inhabiting tropical islands are diadromous and depend on unimpeded connections between freshwater and marine environments to complete their life cycles. The presence of these species in urban streams is best explained by longitudinal connectivity rather than by the degree of urban impact. Finally, in streams that remain connected to marine environments, the presence of native shrimps and fishes is strongly related to the physical habitat. Fish assemblages in channelized and severely altered stream reaches are almost completely devoid of native fauna and tend to be dominated by non-native species. In contrast, relatively diverse shrimp and fish assemblages can be found in reaches that retain their physical habitat complexity, even when they are impacted by urbanization. Our understanding of urban impacts on tropical island streams remains limited. However, the identification of key aspects can help us better understand urban impacts on streams in tropical islands, and best focus our management and research efforts to protect these unique ecosystems.     

Skin lighteners, Black consumers and Jewish entrepreneurs in South Africa

This article considers the rise and decline of South Africa's lucrative and controversial skin-lighteners market through examination of the business history of the largest manufacturers, Abraham and Solomon Krok, and their evolving personas as millionaires and philanthropists. Such examination reveals how the country's skin-lighteners trade emerged as part of the broader growth of a black consumer market after the Second World War and how elements of that market became the target of anti-apartheid protests in subsequent decades. It also demonstrates how the Kroks' experiences as second-generation Jewish immigrants shaped their involvement in the trade and how, later, their self-identification as Jewish philanthropists informed their efforts to rehabilitate their reputations following South Africa's 1990 ban on all skin lighteners. Such efforts include the building of Johannesburg's highly acclaimed Apartheid Museum, modelled after the United States Holocaust Memorial Museum. This article explores the profound ironies that some South Africans see in the fact that a museum dedicated to commemorating those who suffered under and, ultimately, triumphed against state racism was financed by a family fortune generated through the sale of skin lighteners to black consumers.     

Limits to expansion: transnational corporations and territorial embeddedness in the Japanese temporary staffing market

Recent changes to employment legislation have combined with shifting macro‐economic conditions to drive dramatic growth in Japan's temporary staffing industry. Leading transnational staffing agencies have sought to capitalize on this growth as part of their wider globalization strategies but have faced substantial challenges both in entering the market and in their subsequent attempts at expansion. In this article, we explore the ways in which the particularities of the Japanese host market regulatory and institutional environment combine with the inherent characteristics of the temporary staffing business model to challenge the expansionary strategies of these firms. We argue that while transnational firms have sought to adapt their business practices and strategies to the Japanese case, the attributes of the Japanese staffing market mean they have been unable to make significant inroads into the dominant market shares held by their domestic rivals.     

Teenage employment and career readiness

Most American youth hold a job at some point during adolescence, but should they work? This article presents a broad overview of teenage employment in the United States. It begins by describing which teenagers work and for how long and then focuses attention on the consequences (both good and bad) of paid work in adolescence. It then presents recent nationally representative data from the Monitoring the Future Study suggesting that limited hours of paid work do not crowd out developmentally appropriate after-school activities. A review of the literature also supports the idea that employment for limited hours in good jobs can promote career readiness and positive development. The article concludes with a discussion of the implications of youth work for practitioners and policymakers who are delivering career-related programming.     

Infant Distress and Regulatory Behaviors Vary as a Function of Attachment Security Regardless of Emotion Context and Maternal Involvement

Differences in infant distress and regulatory behaviors based on the quality of attachment to mother, emotion context (frustration versus fear), and whether or not mothers were actively involved in the emotion-eliciting tasks were examined in a sample of 98 16-month-old infants and their mothers. Dyads participated in the Strange Situation, a limiting task designed to elicit infant frustration, and a novelty task designed to elicit infant fear. Mothers were asked to remain uninvolved during the first minute of each task, and then instructed to engage with their infants as they wished for the remaining three minutes. Independent of concurrent maternal sensitivity, resistant infants were significantly more distressed than secure and avoidant infants. Avoidant infants engaged in fewer active mother-oriented regulation behaviors than secure and resistant infants and engaged in more self-soothing in the mother involved condition than the mother uninvolved condition. Resistant infants engaged in more physical comfort with their mothers and more venting than both secure and avoidant infants, and exhibited a smaller variety of adaptive non-mother-oriented strategies than did secure infants. There were few differences in infant distress and regulatory behaviors as a function of emotion task and maternal involvement. Limitations and implications for future research are discussed.     

The effects of family stressors on substance use initiation in adolescence

Smoking and drinking are critical problems in adolescence that have long-term adverse impacts on health and socio-economic factors. We examine the extent to which family stresses influence the timing of initiation of smoking and drinking. Using national panel data from the National Educational Longitudinal Study (NELS) we capitalize on the survey design and use school-level fixed effects that control for the local environments, including prices of cigarettes and alcohol. In addition, we narrow our control group to classmates who will experience a similar stressor in the future. We find that a composite measure of family stressors when young increases the likelihood of initiating tobacco and alcohol use, with much of the impact attributable to parental divorce. In our baseline estimates, the composite stress measure is associated with a 30% increase in the likelihood of smoking and a 20% increase in drinking. When we control for multiple sources of confounding, the impact shrinks and remains significant for smoking but not for drinking. We conclude that studies which do not control for confounding are likely to significantly overestimate the impact of family stress on substance use. Our approach helps to move the literature forward by separating causal results from spurious associations.     

Overcoming the Neglect of Social Process in Cross‐National and Comparative Criminology

How and why crime rates vary across different societal and cultural contexts has been a perennial question within criminological research. Numerous studies have emerged in recent years responding to calls for criminology to examine the cross‐cultural relevance of contemporary theory. While many of these studies have made significant advances, a great deal of work remains to be done in the development of theory, measurement, and methods. The present article examines the state of cross‐national criminological research, including a discussion of challenges in examining key theoretical questions. Promising avenues for overcoming issues with data and developing key theoretical perspectives to better assess how social processes explain cross‐national variations of crime are discussed.     

Potential strategies to avoid progestogen-induced premenstrual disorders

Non-hormonal approaches to premenstrual syndrome (PMS) treatment such as selective serotonin reuptake inhibitors are by no means effective for all women and frequently we must resort to endocrine therapy. During many of the hormonal approaches, PMS-like symptoms can be introduced or re-introduced during the necessary cyclical or continuous progestogen component of the therapy. This is seen with combined oral contraception, progestogen only contraception, progestogen therapy for heavy menstrual bleeding and endometriosis, sequential hormone replacement therapy and any therapeutic strategy for premenstrual syndrome where it is necessary to provide endometrial protection, including estrogen suppression of ovulation or add-back during gonadotrophin releasing hormone suppression. The link to progestogen is very often missed by health professionals. When the pattern of symptoms mimics the cyclicity of PMS, it is termed progestogen-induced premenstrual disorder. The need to use progestogen to protect the endometrium from the proliferative actions of estrogen can pose insurmountable difficulties in managing premenstrual disorders. In the absence of any really useful evidence, nearly all practice in this area depends on clinician experience. We cannot afford to wait for adequate research evidence to be produced - it never will - and so we must rely on empirical findings, clinical experience, theoretical strategies and common sense.     

Knox meets Cox: Adapting epidemiological space-time statistics to demographic studies

Many important questions and theories in demography focus on changes over time, and on how those changes differ over geographic and social space. Space-time analysis has always been important in studying fertility transitions, for example. However, demographers have seldom used formal statistical methods to describe and analyze time series of maps. One formal method, used widely in epidemiology, criminology, and public health, is Knox’s space-time interaction test. In this article, we discuss the potential of the Knox test in demographic research and note some possible pitfalls. We demonstrate how to use familiar proportional hazards models to adapt the Knox test for demographic applications. These adaptations allow for nonrepeatable events and for the incorporation of structural variables that change in space and time. We apply the modified test to data on the onset of fertility decline in Brazil over 1960–2000 and show how the modified method can produce maps indicating where and when diffusion effects seem strongest, net of covariate effects.     

Climate change and population migration in Brazil’s Northeast: scenarios for 2025–2050

This research contributes to an understanding of the relationship between climate change, economic impacts and migration. We model the long-term relationship (up to 45 years of projection) between demographic dynamics—particularly migration—driven by changes in the performance of the economy due to climate changes in the Northeast region of Brazil. The region is of particular relevance to the study of climate change impacts given its large human population (28% of Brazil’s population) and high levels of impoverishment, having an extensive semi-dry area which will be severely impacted by growing temperatures. Ultimately, the integrated model generates state- and municipal-level migration scenarios based on climate change impacts on the primary economic sectors and their articulations with other sectors. Results suggest that the predicted climate changes will impact severely the agriculture sector in the region, acting as a potential migration push factor to other regions in the country. Finally, we discuss how the increased vulnerability of some groups, particularly migrants, can be factored into Brazilian public policy and planning.