Insect-Habitat Relationships in Intermittent Streams of Eastern South Dakota

Relationships between habitat and invertebrate community structure are an important aspect of bioassessment. Little effort has been made to address these relationships in intermittent streams. The objective of this effort was to examine relationships between habitat and insect community metrics in intermittent streams in Eastern South Dakota. Habitat parameters were measured at 21 sites August 2001 and April, June and August 2002. Aquatic insect samples were collected from all sites, August through October 2001 and April through September 2002. Spearman rank correlation analysis was performed on mean site values (n=21) for habitat and insect community metrics. Only significant correlations (p\u3c0.05) are reported here. Several invertebrate metrics were positively correlated with substrate, bank, and flow measurements. Percent Chironomidae and sprawlers were associated with percent unstable substrate (rho = 0.41 and 0.45, respectively) while percent Ephemeroptera plus Trichoptera were positively associated with fine gravel (rho = 0.47). Numbers of filterers were associated with greater bank erosion, undercut banks and stream flow (rho = 0.42, 0.60 and 0.90, respectively). In contrast, percent Diptera and Trichoptera and Ephemeroptera richness were negatively associated with emergent vegetation (rho = -0.46 to -0.50) and percent predators were negatively associated with stream flow and percent bank erosion (rho = -0.58, -0.73, respectively). These results demonstrate strong relationships between insect community composition, richness and guild metrics and habitat characteristics which may facilitate bioassessment of intermittent streams in Eastern South Dakota

The role of rapid maxillary expansion in the promotion of oral and general health

Rapid maxillary expansion (RME) is an effective orthopedic procedure that can be used to address problems concerned with the growth of the midface. This procedure also may produce positive side effects on the general health of the patient. The aim of the present consensus paper was to identify and evaluate studies on the changes in airway dimensions and muscular function produced by RME in growing patients. A total of 331 references were retrieved from a database search (PubMed). The widening of the nasal cavity base after midpalatal suture opening in growing patients allows the reduction in nasal airway resistance with an improvement of the respiratory pattern. The effects of RME on the upper airway, however, have been described as limited and local, and these effects become diminished farther down the airway, possibly as a result of soft-tissue adaptation. Moreover, limited information is available about the long-term stability of the airway changes produced by RME. Several studies have shown that maxillary constriction may play a role in the etiology of more severe breathing disorders such as obstructive sleep apnea (OSA) in growing subjects. Early orthodontic treatment with RME is able to reduce the symptoms of OSA and improve polysomnographic variables. Finally, early orthopedic treatment with RME also is beneficial to avoid the development of facial skeletal asymmetry resulting from functional crossbites that otherwise may lead to functional and structural disorders of the stomatognathic system later in life