Laura Thomas - Academia.edu (original) (raw)
Uploads
Papers by Laura Thomas
Ecological Research, 2002
Competitive interactions were compared under field and greenhouse conditions for three representa... more Competitive interactions were compared under field and greenhouse conditions for three representative tallgrass prairie species, Echinacea purpurea, Panicum virgatum and Ratibida pinnata. These were planted in monoculture and in mixtures of two species using a replacement series design with groups of four or eight plants. Competition was determined from shoot dry weight data collected during 120 days in the greenhouse and after 415 days in the field. Yields declined with increased density of a single species in the greenhouse from 40 days onward and in the field. Relative yields were up to 100% higher in mixtures than in monocultures for all species early on in the greenhouse experiment. Later in the experiment and in the field relative yields of E. purpurea decreased in the presence of P. virgatum and R. pinnata, whereas relative yields of these two species increased in the presence of E. purpurea. There were correlations in relative yield between the field and the greenhouse experiment at 80 and 120 days. In the greenhouse P. virgatum maintained higher net assimilation rates than the other species. Relative growth rates of all species were higher in monoculture and in mixtures up to 40 days, after which they declined, especially for E. purpurea in mixtures. In the field, higher light intensities occurred in pure stands of E. purpurea than in mixed stands with other species. The order of competitive ability that was apparent from these field and greenhouse studies, P. virgatum = R. pinnata > E. purpurea, could be partially explained by photosynthetic rates in relation to canopy light interception.
American Journal of Psychiatry, 2010
Objective-To understand disorder-unique and common pathophysiology, studies in multiple patient g... more Objective-To understand disorder-unique and common pathophysiology, studies in multiple patient groups with overlapping symptoms are needed. Deficits in emotion processing and hyperarousal symptoms are prominent features of bipolar disorder, attention deficit hyperactivity disorder (ADHD), and severe mood dysregulation. The authors compared amygdala response during emotional and nonemotional ratings of neutral faces in youths with these disorders as well as a group of healthy comparison youths.
Environmental Health Perspectives, 2008
Environmental Health Perspectives, 2008
Ecological Research, 2002
Competitive interactions were compared under field and greenhouse conditions for three representa... more Competitive interactions were compared under field and greenhouse conditions for three representative tallgrass prairie species, Echinacea purpurea, Panicum virgatum and Ratibida pinnata. These were planted in monoculture and in mixtures of two species using a replacement series design with groups of four or eight plants. Competition was determined from shoot dry weight data collected during 120 days in the greenhouse and after 415 days in the field. Yields declined with increased density of a single species in the greenhouse from 40 days onward and in the field. Relative yields were up to 100% higher in mixtures than in monocultures for all species early on in the greenhouse experiment. Later in the experiment and in the field relative yields of E. purpurea decreased in the presence of P. virgatum and R. pinnata, whereas relative yields of these two species increased in the presence of E. purpurea. There were correlations in relative yield between the field and the greenhouse experiment at 80 and 120 days. In the greenhouse P. virgatum maintained higher net assimilation rates than the other species. Relative growth rates of all species were higher in monoculture and in mixtures up to 40 days, after which they declined, especially for E. purpurea in mixtures. In the field, higher light intensities occurred in pure stands of E. purpurea than in mixed stands with other species. The order of competitive ability that was apparent from these field and greenhouse studies, P. virgatum = R. pinnata > E. purpurea, could be partially explained by photosynthetic rates in relation to canopy light interception.
American Journal of Psychiatry, 2010
Objective-To understand disorder-unique and common pathophysiology, studies in multiple patient g... more Objective-To understand disorder-unique and common pathophysiology, studies in multiple patient groups with overlapping symptoms are needed. Deficits in emotion processing and hyperarousal symptoms are prominent features of bipolar disorder, attention deficit hyperactivity disorder (ADHD), and severe mood dysregulation. The authors compared amygdala response during emotional and nonemotional ratings of neutral faces in youths with these disorders as well as a group of healthy comparison youths.
Environmental Health Perspectives, 2008
Environmental Health Perspectives, 2008