University of Puerto Rico, Medical Sciences Campus

About: University of Puerto Rico, Medical Sciences Campus is a education organization based out in San Juan, Puerto Rico, United States. It is known for research contribution in the topics: Population & Medicine. The organization has 1711 authors who have published 1496 publications receiving 27756 citations.

Geophagy amongst rhesus macaques on Cayo Santiago, Puerto Rico

Abstract: Soil mining and eating (geophagy) behavior of rhesus macaques (Macaca mulatta) on Cayo Santiago, Puerto Rico, is described and assessed with respect to the chemical, geochemical, and mineralogical composition of the ingested materials. The samples forming the uneaten (control) and eaten (matrix and blocky) groups of soils come from the top and flanks of a marine terrace underlain with volcanic tuff on Cayo Santiago, off the east shore of Puerto Rico. Both the uneaten and geophagy samples were analyzed to determine particle size distributions, clay and primary mineralogy, and soil chemical and geochemical compositions. Primary minerals such as orthoclase and plagioclase feldspar in the clay fraction is higher in the control group than in the ingested samples. Both the control and matrix plus blocky samples have moderate to abundant amounts of kaolinite and halloysite (both silicon:aluminum = 1:1 type clay minerals) that may be important as a stimulus to geophagy behavior. The pH, total salts, and phosphorus levels in both the control and geophagy samples show considerable overlap with little clear indication of causal factors. Analysis of the geochemical data showed no clear cut elemental differences to suggest elemental supplementation as a possible explanation for mining and eating of tropical soil. It is possible that rhesus macaques ingest clay to obtain kaolinite/halloysite minerals which may alter the taste of their provided food, and may act as pharmaceutical agents to alleviate intestinal ailments such as diarrhea.

Morbidity associated with four-wheel all-terrain vehicles and comparison with that of motorcycles.

Abstract: Background: The U.S. Consumer Product Safety Commission in their annual report (2001) of all-terrain vehicle (ATV) deaths and injuries concluded that in the late 1990s there had been a gradual increase in the number of deaths and injuries related to ATV collisions. The objective of our study was to describe the morbidity of four-wheel all-terrain vehicle collisions (ATVCs) and compare them with motorcycle collision (MCC) victims. Methods: This was a 24-month (April 2000-November 2002) retrospective review of all trauma patients admitted. Statistical significance was defined at p < 0.05. Results: A total of 2,380 blunt trauma patients were admitted, of which 74 (3.1%) were ATVC victims and 169 (7.1%) were MCC victims. The average age was 23.9 ′ 9.4 years for ATVC victims and 29.1 ′ 11.5 years (p < 0.001) for MCC victims. The median Injury Severity Score was 16.0 for the ATVC group and 13 for the MCC group (p = 0.106). ATVC patients had a higher incidence of head and neck injuries (56%) than MCC patients (30%) (p < 0.001). The incidence of chest and abdominal injuries was similar between groups. Mortality occurred in 15 of 74 (20%) ATVC patients and 24 of 169 (14.2%) MCC patients (p = 0.236). Conclusion: This study demonstrates that ATVCs are associated with significant morbidity and mortality. When compared with MCCs, ATVCs have similar mortality and a much higher incidence of head injuries. National tracking of ATVCs should be continued and improved in an effort to assist legislators in enacting laws protecting the riders of ATVs.

Sexually selected skin colour is heritable and related to fecundity in a non-human primate

Abstract: Sexual selection promotes the prevalence of heritable traits that increase an individual's reproductive rate. Despite theoretically strong directional selection, sexually selected traits can show inter-individual variation. Here, we investigate whether red skin ornamentation, a rare example of a male mammalian trait involved in mate attraction, influences fecundity and is heritable in rhesus macaques (Macaca mulatta), and explore the mechanisms that are involved in maintaining trait variation. Interestingly, the trait is expressed by and is attractive to both sexes. We collected facial images of 266 free-ranging individuals and modelled skin redness and darkness to rhesus macaque vision. We used 20 years of genetic parentage data to calculate selection gradients on the trait and perform heritability analyses. Results show that males who were both darkly coloured and high-ranking enjoyed higher fecundity. Female skin redness was positively linked to fecundity, although it remains unclear whether this influences male selectiveness. Heritability explained 10-15% of the variation in redness and darkness, and up to 30% for skin darkness when sexes are considered separately, suggesting sex-influenced inheritance. Our results suggest that inter-individual variation is maintained through condition-dependence, with an added effect of balancing selection on male skin darkness, providing rare evidence for a mammalian trait selected through inter-sexual selection.