Relationships among nutrients,chloride and biological indices in urban Maryland streams

Using a spatially extensive urban database constructed from the Maryland Biological Stream Survey (MBSS), we describe the relationships of nutrients in small-order streams to eight defined categories of percent catchment urbanization, correlations between chloride and conductivity in urban streams, and relationships between nutrients and chloride with two Maryland-specific indices of biotic integrity for benthic macroinvertebrates and fish assemblages. Stream nutrients become elevated with increasing percent catchment urbanization, followed by increases in all four measured nitrogen species and total phosphorus at catchment urbanization levels greater than 10%. There was a strong collinear relationship (r ² = 0.90) between chloride and conductivity (trimeans) across all eight urbanization classes, where Cl (mg/L) = −0.397 + 0.188*conductivity (μS/cm). Critical values for all water quality parameters with the two Maryland biological indices were derived using quantile regression, with significant regressions developed for 11 of 16 water quality parameters and the two biotic indices. For nitrate (NO₃-N), the critical thresholds between fair and poor stream quality for the two Maryland biological indices were 0.83 mg/L (benthic macroinvertebrate assemblages) and 0.86 mg/L (fish assemblages). Increasing stream nutrient and chloride levels, associated with widespread catchment urbanization intensity, now affect many small streams in Maryland, with implications for decreasing water quality in major tributaries and the Chesapeake Bay.     

Die Wirkung von Beratern

The theoretical basis behind consultancy does not match its importance to the economy. Although theory building research has been advanced since the 1990s, it still remains fragmentary. The impact of these consulting theories on practice has therefore been limited. This paper provides a contribution to this recent field of research. Based on the Social Systems Theory by Luhmann, a model outlining the impact of consultancy is presented. Three empirical cases outline the usefulness of the presented model in practice.     

Systemic lupus erythematosus and hormone replacement therapy

The indications for hormone replacement therapy (HRT) in postmenopausal women is the treatment of climacteric symptoms and the prevention of osteoporosis. Women with systemic lupus erythematosus (SLE) are more likely to have a premature menopause, osteoporosis and cardiovascular disease. HRT can induce SLE flares and cardiovascular or venous thromboembolic events. Therefore it should not be used in women with active disease or those with antiphospholipid (aPL) antibodies. In general, it should be used only for patients without active disease, a history of thrombosis or aPL antibodies. Non-oral administration of estrogen is recommended because of its lesser effect on coagulation. With regard to the progestogen, progesterone or pregnane derivatives are preferred. Otherwise, non-estrogen-based strategies should be used.     

A Reexamination of Card and Krueger's State-Level Study of the Minimum Wage

Card and Krueger's (1995) difference-in-difference study of the 1990-1991 federal minimum wage hikes compared states by the proportion of workers directly affected by the minimum wage. They found "no evidence that the increase in the minimum wage significantly lowered teenage employment rates more in highly affected states" and they concluded the minimum wage did not reduce employment. Their paper was highly influential and convinced many that the minimum wage did not reduce employment. However, when I apply their model to the 1996-1997 federal minimum wage hike, I find that increases in the minimum wage significantly lowered teenage employment rates more in highly affected states. Using Card and Krueger's interpretation, this implies the minimum wage did reduce teenage employment.     

Government Intervention in Public Sector Industrial Relations: Lessons from the Alberta Teachers’ Association

In the public sector, Canadian governments intervene frequently in labor disputes by suspending collective bargaining and curtailing legal strikes. Previous research has focused on the contours of government intervention, such as its overall effects on collective bargaining and strikes. The discussion highlights one actor, a government, restricting the behavior of another actor, a union, using legislation and policy making. As a result, we know less about more micro-level elements and implications of the process of government intervention. I address these themes using a detailed case study of the Alberta Teachers’ Association and the strikes it coordinated in 2002.

The Experience-Earnings Profile: Productivity-Augmenting or Purely Contractual? Evidence from the UK

We test the human capital interpretation of the experience-earnings profile. Does the upward sloping portion of the experience-earnings profile reflect on-the-job training which in turn causes the experience-productivity profile to slope upwards, or do purely contractual factors determine the nature of life-cycle earnings. Herein, we provide additional evidence on the relationship between productivity and earnings by examining earnings differentials in the UK academic labor market for economists. Using a test first suggested by Mincer, we find that the empirical results are consistent with human capital theory. We find that, although the positive relationship between earnings and experience persists when individual productivity measures are included in the salary equations for lecturers and senior lecturers, the positive relationship becomes statistically insignificant when the same productivity measures are included in the salary equations for professors. For lecturers and senior lecturers, the experience-salary profile properly reflects the structure of the national pay scale rather than variations in individual research productivity. At the professor level, where individual salaries are not determined by a pay scale, the data support the human capital explanation of the positive experience-earnings profile.

Reading your Counterpart: The Benefit of Emotion Recognition Accuracy for Effectiveness in Negotiation

Using meta-analysis, we find a consistent positive correlation between emotion recognition accuracy (ERA) and goal-oriented performance. However, this existing research relies primarily on subjective perceptions of performance. The current study tested the impact of ERA on objective performance in a mixed-motive buyer-seller negotiation exercise. Greater recognition of posed facial expressions predicted better objective outcomes for participants from Singapore playing the role of seller, both in terms of creating value and claiming a greater share for themselves. The present study is distinct from past research on the effects of individual differences on negotiation outcomes in that it uses a performance-based test rather than self-reported measure. These results add to evidence for the predictive validity of emotion recognition measures on practical outcomes.

Earnings Differentials of Seafarers

I investigate the earnings differentials among union and nonunion seafarers, across seafarer occupations, and with respective to other transport operatives. The empirical results suggest that the union and nonunion weekly earnings of captains/mates are comparable, and the union earnings gap for sailors/deckhands is positive. The union (nonunion) weekly earnings of captains/mates are 14.7 (30.5) percent greater than those of sailors/deckhands; the union weekly earnings of captains/mates (sailors/deckhands) are 12.6% greater (9.5% less) than those of truck drivers; and the nonunion weekly earnings of captains/mates (sailors/deckhands) are 33.0% greater (6.2% less) than those of truck drivers. The sailor/deckhand and truck driver earnings differentials are contrary to the general belief that the earnings of truck drivers are less than those of other operative occupations involved in transporting intermodal cargo.

Virtual Interpersonal Touch and Digital Chameleons

We studied the characteristics of hand touch with a mechanical device that approximated a handshake, and we then examined the effect of handshake mimicry on assessment of a partner. Two participants interacted with a force-feedback joystick that recorded each of their hand movements individually. The two participants then greeted one another by feeling the recording of the other person’s movements via the force-feedback device. For each dyad, one of the participants actually received his or her own virtual handshake back under the guise that it was the other person’s virtual handshake. Results demonstrated three significant findings. First, for any given participant, a metric that took into account position, angle, speed, and acceleration of the hand movements correlated highly within individuals across two handshakes. Second, across participants, these metrics demonstrated specific differences by gender. Finally, there was an interaction between gender and mimicry, such that male participants liked people who mimicked their handshakes more than female participants did. We discuss the implications of these findings and relate them to theories of social interaction.