Insect species composition and diversity on intensive green roofs and adjacent level-ground habitats

While it is expected that green roofs support a wider variety of insects compared with conventional roof surfaces, few studies have quantified insect diversity on green roofs. Even fewer have attempted to determine whether green roofs can support insect communities comparable to level-ground urban habitats. In this study, insect richness, abundance and diversity indices were compared between five pairs of intensive green roofs and adjacent ground-level habitat patches in downtown Halifax, Nova Scotia. Pitfall traps were set at each site, collected bi-weekly between May-October 2009 and captured insects were identified to morphospecies (except where taxonomic expertise was available). No significant differences in richness, abundance or any of the indices (S, H’, E_var) were detected in analysis, which included plant species richness, site area and sampling effort as covariables. However, richness and abundance tended to be greater at ground level for all orders (except Heteroptera), and diversity appeared to increase away from the downtown core. Insect composition differed slightly between green roof and ground-level sites; only 17 species were collected from a single site type in numbers greater than five specimens. Nevertheless, a wide variety of insects, including many uncommon species were collected from green roofs, supporting the idea that these habitats can contribute to sustaining biodiversity in cities.     

Issue Information

While engaged in research and teaching regarding racism in US organizations, members of the writing team have frequently found that conscientious humour and the meaningful lessons it can encode provide needed releases from the stress associated with social justice work as well as serve as an effective pedagogical tool. Taking inspiration from contemporary satirical humourists, including Robin Thede, Issa Rae, Dave Chappelle and Jordan Peele, who have used comedy to expose serious aspects of racism, as well as leading critical race theorists’ use of fictional chronicles about race we present a comedic chronicle centred around an African American protagonist who demonstrates a variety of coping and resistance strategies in conversations with a well‐intentioned yet culturally insensitive white male co‐worker who regularly engages her about her hair.     

INTERPERSONAL DISCRIMINATION AGAINST HMONG AMERICANS: Parallels and Variation in Microlevel Racial inequality

Different racial and ethnic minorities are commonly compared across various measures of macrolevel inequality but have thus far not been compared with respect to microlevel inequality. Using data from interviews with forty-eight Hmong Americans, this article systematically extends Feagin's (1991) analysis of interpersonal discrimination against African Americans to the experiences of everyday racism among a group of foreignborn Asian Americans. Hmong Americans report all of the forms of interpersonal discrimination that Feagin documents for African Americans, suggesting that minorities face a common inequality structure in public face-to-face encounters. Nativism and limited English proficiency, two factors that Feagin did not identify as affecting African Americans, are also important components of interpersonal discrimination against Hmong Americans. These additional dimensions of interpersonal discrimination against suggest that macrolevel patterns of racial and ethnic inequality can lead to variation in microlevel inequality.     

Colonial Military Garrisons as Labor-Market Shocks: Quebec City and Boston, 1760–1775

The military occupation of Boston in 1768 shocked the city's labor market. The soldiers, who were expected to supplement their pay by working for local businesses, constituted an influx equal to 12.5 percent of greater Boston's population. To assess the importance of this shock, we use the case of Quebec City, which experienced the reverse process (i.e., a reduction in the British military presence from close to 18 percent of the region's population to less than 1 percent). We argue that, in Boston, the combination of the large influx of soldiers and a heavy tax on the local population in the form of the billeting system caused an important wage reduction, while the lighter billeting system of Quebec City and the winding down of the garrison pushed wages up. We tie these experiences to political developments in the 1770s.     

COMPONENTS OF VARIANCE MODELS WITH TRANSFORMATIONS

Power transformations are a popular way to improve the agreement between the observations and the assumptions in a statistical model. In this paper it is assumed that the data, after appropriate power transformation Λ, satisfies a variance components model, with independent Gaussian components. The focus is on inference for quantities which have an interpretation regardless of the choice of Λ (Carroll & Ruppert, 1981) – in particular the intraclass correlation coefficient ρ, the predicted probability of a new observation being less than a specified value and the predicted quantile. It is shown that, in the case Λ= 0, the asymptotic variance of ρ is the same, whether or not one treats Δ as estimated or as known. This supports an empirical conjecture of Solomon (1985). For predicted probabilities and predicted quantiles the variance when A is estimated is shown to be only slightly greater than the variance assuming Δ is known, except in the tails of the distribution where there can be substantial difference between the two variances.     

Child abuse: differential diagnosis, differential treatment

This study assessed the relationship between treatment intensity and rehabilitation at discharge of child abusers whose MMPI profiles revealed high levels of psychological distress. It should be noted that this sample does not represent the child abuser who requires only a support group or outpatient counseling. Because of repeated failures at other social service agencies coupled with the court selection process, this sample may be described as having been screened for intransigence, severity of symptomatology, and resistance to previous attempts at treatment. It is noteworthy that participation in treatment was court-ordered, thereby diminishing the possibility of improvement because of subject characteristics, emotional availability or stamina in the treatment process. In this exploratory study, the association between treatment intensity and assessed rehabilitation yielded a positive and statistically significant relationship. The client who received intense weekly treatment for longer durations was assessed as having a higher degree of rehabilitation. This finding is important particularly for a population that exhibited an abnormally high degree of psychological distress. As an initial investigation, results support the need for differential diagnosis and subsequent differential treatment of child abusers. Without differential diagnosis, treatment needs may go unrecognized; without intense and sustained treatment, the needs of the highly distressed child abuser may go unmet.     

Organization of the planning department in a divisionalized concern

This article is based upon an assignment carried out by the author concerned with organization for planning in a company formed as a result of a merger. Possible organizational solutions are discussed and the recommendations of the author and his colleague outlined.     

Urban politics and the study of urban poverty: Promising developments and future directions

The study of urban poverty is alive and well in sociology. The study of urban politics, by contrast, has stagnated. Though scholars agree that politics shapes the creation and durability of urban poverty, analytical connections between the two subfields are rarely made explicit. In this article, I make the case for a more integrated body of research. I first illustrate how urban poverty scholars implicitly discuss politics, and conversely, how urban politics scholars implicitly discuss poverty. I then highlight recent developments in the literature and propose two paths forward—by no means the only paths forward, but two ways to jumpstart greater conversation across both subfields. For the urban poverty literature, a focus on organizations can help scholars analyze political dynamics more directly. And for the urban politics literature, an emphasis on political mechanisms rather than overarching perspectives can disrupt the current theoretical malaise. These two moves can advance both literatures while drawing them closer together.     

Quantifying the Economic Impact of Hydraulic Fracturing Proppant Selection in Light of Occupational Exposure Risk and Functional Requirements

Selection of an effective and economic proppant material for hydraulic fracturing is an important design choice to optimize the production of oil and natural gas. Proppants are made of silica (quartz sand), alumina, resin-coated silica, ceramics, and others. These materials can be toxic to varying degrees and lead to health problems in the employees handling them primarily due to inhalation exposure. Proppants are selected based on grain size, shape, strength, and cost. Current use is dominated by crystalline silica—the proppant that also has the greatest hazard as an inhalation toxin. Existing research describes the effect of silica on human health, but little research has been done to determine the risk-reduction and social-cost-effectiveness associated with using alternative proppants in light of the health risks. This study quantifies the relative risks or benefits to human health by the use of these proppants through an economic analysis considering the health-related economic impact and its technical attributes. Results show that the use of each ton of silica proppant results in $123 of external costs from fatalities and nonfatal illness arising due to exposure to silica for a crew handing 60,000 tons of proppants. If these health-related externalities were incorporated into the cost, silica proppant could be economically replaced by less harmful, more expensive alternatives for hydraulic fracturing crews handling less than 60,000 tons of proppant each year.