Potential nitrogen mineralization responses of urban and rural forest soils to elevated temperature in Louisville,KY

Soil nitrogen (N) mineralization is an important process determining terrestrial N availability, and evidence suggests elevated temperatures will enhance N mineralization rates. Along a 40 km urban-rural gradient of chestnut oak forest stands in Louisville, KY, we expected N mineralization rates would be higher in urban than in rural forests in part due to increased temperatures caused by the urban heat island. However, a 12-month field study along this Louisville gradient showed that annual N mineralization rates were lower in urban than in rural stands. Since variation in precipitation inputs and other factors across this land-use gradient may be influencing soil N mineralization rates, we conducted a three-month soil incubation experiment in the lab to determine the extent to which a + 2 °C temperature difference could affect soil N mineralization in urban and rural soils. Across the range of temperatures tested, rural soils mineralized N at twice the rate of urban soils under base (7.86 vs. 3.65 mg N kg^?1 AFDW soil d^?1) and elevated (9.08 vs. 4.76 mg N kg^?1 AFDW soil d^?1) temperatures (p < 0.01). A 2 °C temperature difference, did not significantly alter total inorganic N production in urban (p = 0.272) or rural soils (p = 0.293). The proportion of nitrate produced was lower in the urban (15.1 %) than in the rural soils (72.3 %; p < 0.01). These results suggest that differences in soil organic matter quality and potentially decomposer community composition are the primary explanatory factors for forests along this Louisville gradient.     

Elevated phosphorus: dynamics during four years of green roof development

Green roofs are emerging engineered ecosystems that provide multiple benefits, but many are constructed with nutrient-rich substrate and have been found to leach out high levels of phosphorus (P) in runoff. It is unclear, however, how long green roofs act as sources of P or what mechanisms are responsible for these net losses. We measured P concentrations in runoff water over 4 years from a 1–5 year old extensive green roof in Cincinnati, OH, USA, produced a model to predict runoff P levels into the future, and validated predictions using runoff from 2 nearby extensive green roofs. P concentrations in runoff from the focal green roof were on par with heavily fertilized agroecosystems and displayed strong seasonal dynamics and a rapid decline over the 4-year study. Runoff measurements and changes in substrate P content over a 2-year period were used to estimate a mass balance for green roof P. P loss from the substrate was substantial (4.55 ± 2.3 g P/m²/yr), but only a small portion of the loss was attributable to leaching of P in runoff (0.19–0.65 g P/m²/yr). Missing P may be attributed to a combination of plant uptake and altered P form and binding strength, but further research is needed to precisely identify the mechanisms of P depletion. Our results also suggest that these and similar extensive green roofs are likely to act as environmentally significant sources of P for 10 or more years following roof installation, highlighting the need for reductions in initial substrate P content.     

Dynamic heterogeneity: a framework to promote ecological integration and hypothesis generation in urban systems

Urban areas are understood to be extraordinarily spatially heterogeneous. Spatial heterogeneity, and its causes, consequences, and changes, are central to ecological science. The social sciences and urban design and planning professions also include spatial heterogeneity as a key concern. However, urban ecology, as a pursuit that integrates across these disciplines, lacks a theoretical framework that synthesizes the diverse and important aspects of heterogeneity. This paper presents the concept of dynamic heterogeneity as a tool to explore how social and ecological heterogeneities interact and how they together act as both an outcome of past interactions and a driver future heterogeneity and system functions. To accomplish this goal, we relate heterogeneity to the fundamental concept of the human ecosystem. The human ecosystem concept identifies key processes that require operationalized models of dynamic heterogeneity in three process realms: the flow of materials, the assembly of urban ecosystem biota, and the locational choices humans make concerning land. We exemplify a specific dynamic model of heterogeneity in each of these realms, and indicate a range of complementary statistical approaches to integrate the drivers and outcomes of dynamic heterogeneity across the three realms. We synthesize a hierarchical framework for a theory of dynamic urban heterogeneity, noting its complementarity to other major urban theories and general model approaches. We hypothesize that human actions and structures amplify the dynamics of heterogeneity in urban systems.     

Burnout,coping and suicidal ideation: An application and extension of the job demand-control-support model

Suicidal tendencies are typically considered related to individual traits or predispositions, but some occupations have significantly higher rates than other occupations and the general population. This article proposes that stressful work conditions may be important in understanding occupational variations in suicidal tendencies. It explores the links between work-related factors and burnout, and suicidal thoughts among veterinarians. Burnout appears to be an important mediator in understanding veterinarians’ suicidal tendencies; work conditions that are emotionally exhausting for veterinarians may foster suicidal thoughts. Individual coping strategies are also explored. Emotion-focused strategies of avoidance and alcohol consumption not only exacerbate burnout and suicidal thoughts but also amplify the harmful effects of some job demands. Active problem solving is not as beneficial as expected, but a supportive work environment is a valuable coping resource. Organizational interventions and coping resources effective in reducing burnout may also reduce the risk of suicide for those in service occupations.     

Staff Development as a School Climate Intervention to Support Transgender and Gender Nonconforming Students: An Integrated Research Partnership Model for School Counselors and Counselor Educators

ABSTRACT

This article posits that an integrative research partnership model can assist school counselors in addressing the marginalization of transgender students in schools through staff development. A methodological integration of action research and program evaluation through quantitative and qualitative data collection is explained, and a collaborative process is highlighted. A case example is provided to demonstrate the use of the design.     

Structural and Contextual Factors Regarding the Accessibility of Elective Office for Women of Color at the Local Level

Different from the majority of past research on gender gaps in political officeholding, we adopt an intersectionality framework and move beyond traditional individual factors to explore what implications certain elements in the political opportunity structure may have for women and men of color elected officials serving in county, municipal, and local school board offices. We argue that structural and contextual factors, such as type of institutions, election systems, and jurisdictional racial makeup, may influence the calculations women of color make concerning the accessibility of elective office. Using data from the Gender and Multiracial Leadership (GMCL) project, we find county offices to be the least, and seats on school boards the most, accessible to women of color. Of the types of electoral arrangements, we find multimember districts (MMD) to be the most significant variable predicting the likelihood of women of color in office. Although both Black and Latina women benefit from having a significant share of coethnics or nonwhites in jurisdictions, the two groups of women have an opposite relationship to their racial constituent makeup than that held by their male counterparts.     

Comparison of Two Psycho-Educational Interventions Aimed at Preventing HIV and Promoting Sexual Health Among Portuguese Women

This study compares the efficacy of 2 psychoeducational interventions—ACCENT skills-based and didactic information only—to prevent HIV among Portuguese women. At posttest and follow-up, participants in both intervention groups (n = 127) were more knowledgeable about HIV than at baseline. Although both intervention groups showed an increase in self-reported condom use over time, differences were marginally stronger in the ACCENT group. Both intervention groups showed more positive results than the non-intervention control group (n = 33). The study suggests that HIV prevention interventions can produce significant changes when they target a set of knowledge, social, and cognitive variables relevant to sexual behavior change.     

Semi-parametric segmentation of multiple series using a DP-Lasso strategy

We consider a semi-parametric approach to perform the joint segmentation of multiple series sharing a common functional part. We propose an iterative procedure based on Dynamic Programming for the segmentation part and Lasso estimators for the functional part. Our Lasso procedure, based on the dictionary approach, allows us to both estimate smooth functions and functions with local irregularity, which permits more flexibility than previous proposed methods. This yields to a better estimation of the functional part and improvements in the segmentation. The performance of our method is assessed using simulated data and real data from agriculture and geodetic studies. Our estimation procedure results to be a reliable tool to detect changes and to obtain an interpretable estimation of the functional part of the model in terms of known functions.