Testing prescribed burning to shift an agronomic grass community to a diverse native plant community.

Prescribed burning can be an effective land management tool. Here, we study changes in plant diversity and composition following experimental fire disturbance in microcosm units extracted from a twenty-five-year-old historically reclaimed grassland located at Highland Valley Copper mine in British Columbia (B.C.), Canada. Experimental microcosm units were dominated by agronomic grass species Elymus lanceolatus, Thinopyrum intermedium and Bromus inermis. The disturbance treatment was fire intensity, represented by three levels (light, moderate, and heavy), replicated six times per treatment. Fire intensity was controlled by modifying the weight of dried litter applied to each microcosm unit (50 g,150 g, 200g), along with the time each grass turf was burned (10 s, 15 s, 20 s). One day after the fire treatment was applied, microcosm units were seeded with a native species mix consisting of six grassland species common to southern B.C. to examine effectiveness of plant establishment postburn. Disturbance treatments resulted in higher overall alpha diversity, richness, evenness, and beta diversity. Plant community changes included colonization of seeded native forbs, grasses, and legumes in response to disturbance. Aboveground net primary productivity (ANPP) was net neutral within the light and moderate burning disturbance treatments but resulted in increased ANPP with heavy disturbance. Litter mass reduced plant diversity and ANPP, indicating that litter was a major factor in plant community dynamics. These results suggest disturbance by burning leads to short term positive plant community response towards increasing diversity of semi-arid grasslands, and aids in shifting plant communities to higher diversity composed of an increase in native plant species. Our results also suggest that without active management the gains observed in native species establishment might quickly be out shadowed and restricted by the previously dominant agronomic plant community.

A trial comparing the use of rectal misoprostol plus perivascular vasopressin with perivascular vasopressin alone to decrease myometrial bleeding at the time of abdominal myomectomy.

OBJECTIVE: To compare the efficacy of rectal misoprostol plus perivascular vasopressin with perivascular vasopressin alone as hemostatic agents for the reduction of blood loss during myomectomies. DESIGN: Prospective, randomized, double-blind, controlled study. SETTING: University of the West Indies and Andrews Memorial Hospital. PATIENT(S): Fifty women with symptomatic uterine fibroids, 25 receiving misoprostol and vasopressin and 25 receiving vasopressin alone before myomectomy. INTERVENTION(S): Abdominal myomectomies on patients with symptomatic uterine fibroids. MAIN OUTCOME MEASURE(S): Perioperative blood loss and febrile morbidity. RESULT(S): There were no statistically significant differences in sociodemographic, clinical, or myoma characteristics between the two groups at baseline. Postoperatively, there were no statistically significant differences in perioperative febrile morbidity or blood pressure between the groups. However, the group treated with misoprostol plus vasopressin had statistically significantly lower blood loss (geometric mean with 95% confidence interval, 334 mL [261 to 428] vs. 623 mL [354 to 1,094], a smaller change in hemoglobin (1.6 ± 1.5 vs. 3.0 ± 2.0), and a lower requirement for transfusion. In addition to treatment, significant determinants of blood loss were larger size of fibroids and greater number of fibroids. CONCLUSION(S): We conclude that perivascular vasopressin plus misoprostol caused a significant reduction in blood loss compared with perivascular vasopressin alone. CLINICAL TRIAL REGISTRATION NUMBER: NCT01700478.

Color vision in the giant panda (Ailuropoda melanoleuca).

Hue discrimination abilities of giant pandas were tested, controlling for brightness. Subjects were 2 adult giant pandas (1 male and 1 female). A simultaneous discrimination procedure without correction was used. In five tasks, white, black, and five saturations each of green, blue, and red served as positive stimuli that were paired with one or two comparison stimuli consisting of 16 saturations of gray. To demonstrate discrimination, the subjects were required to choose the positive stimulus in 16 of 20 trials (80% correct) for three consecutivesessions. Both subjects reached criterion forgreen and red. The female subject also reached criterion for blue. The male was not tested for blue. This study is a systematic replication of Bacon and Burghardt's (1976) color discrimination experiment on black bears. The results suggest that color vision in the giant panda is comparable to that of black bears and other carnivores that are not strictly nocturnal.