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The objective of the study described in this article was to evaluate the nitrogen contributions from two onsite wastewater systems (sites 1 and 2) to groundwater and adjacent surface waters in coastal Beaufort County, North Carolina. Groundwater levels and water quality parameters including total nitrogen, nitrogen species, temperature, and pH were monitored from October 2009 to May 2010. Nitrogen was also tested in groundwater from deeper irrigation or drinking water wells from the two sites and six additional neighboring residences. Mean total nitrogen concentrations in groundwater beneath onsite wastewater systems 1 and 2 were 34.3 ± 16.7 mg/L and 12.2 ± 2.9 mg/L, respectively, and significantly higher than background groundwater concentrations (<1 mg/L). Groundwater in the deeper wells appeared not to be influenced by the onsite systems. Groundwater nitrogen concentrations typically decreased with distance down-gradient from the systems, but were still elevated relative to background conditions more than 15 m from the systems and near the estuary. This was a pioneering effort to better understand the link of onsite systems, the fate of nitrogen in the environment, and public health. [ABSTRACT FROM AUTHOR]

Purpose: Fusionless growth modulation is an attractive alternative to conventional treatments of idiopathic scoliosis. To date, fusionless devices achieve unilateral growth modulation by compressing the intervertebral disc. This study explores a device to control spinal alignment and vertebral morphology via growth modulation while excluding the disc in a porcine model.Methods: A device that locally encloses the vertebral growth plate exclusive of the disc was introduced anteriorly over T5-T8 in four immature pigs (experimental) while three underwent surgery without instrumentation (sham) and two were selected as controls. Bi-weekly coronal and lateral radiographs were taken over the 12-week follow-up to document vertebral morphology and spinal alignment modifications via an inverse approach (creation of deformity).Results: All animals completed the experiment with no postoperative complications. Control and sham groups showed no significant changes in spinal alignment. Experimental group achieved a final coronal Cobb angle of 6.5° ± 3.5° (constrained to the four instrumented levels) and no alteration to the sagittal profile was observed. Solely the experimental group ended with consistent vertebral wedging of 4.1° ± 3.6° amounting to a cumulative wedging of up to 25° and a concurring difference in left/right vertebral height of 1.24 ± 1.86 mm in the coronal plane.Conclusions: The proposed intravertebral epiphyseal device, for the early treatment of progressive idiopathic scoliosis, demonstrated its feasibility by manipulating spinal alignment through the realization of local growth modulation exclusive of the intervertebral disc. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study is to better understand how risk factors for coronary heart disease (CHD) mortality may interact.Methods: We conducted a moderator-mediator analysis of a representative national sample of 5027 and 2902 community-dwelling women and men in the first National Health and Nutrition Examination Survey free of CHD in 1982. The outcome was 10-year CHD mortality.Results: Two hundred sixty-seven subjects experienced CHD mortality. In the complete sample, gender moderated the effect of depressive symptoms, and among women, race-ethnicity moderated the effect of nonleisure activity on CHD mortality, defining three subgroups for further analysis: men, white women, and black/other women. Among men, baseline differences from median age (55 to 64 years), systolic blood pressure (129 to 158 mmHg), or self-rated general health ("good" to "poor") were associated with equivalent increases in 10-year CHD mortality from 2.3% to 5.3% [area-under-the-curve effect size (ES)=0.53]. These factors appeared to mediate the effect of education on CHD mortality. Severe depression in men was associated with higher 10-year CHD mortality than less or no depression, 10.0% vs. 2.5% (ES=0.55). Among white women, baseline differences from median age (51 to 65 years) was also associated with 10-year mortality (1.2 to 13.4%, ES=0.56), as was higher blood pressure (125 to 151 mmHg) or worse self-rated health ("very good" to "fair") to a lesser extent (1.2% to 3.5%, ES=0.51).Conclusion: Moderators (gender, race-ethnicity) defined possible pathways to CHD mortality characterized by varying factors and interactions between factors, highlighting potential utility for targeted interventions among community-dwelling persons. [ABSTRACT FROM AUTHOR]

Inadequate understanding of risk factors involved in the progression of idiopathic scoliosis restrains initial treatment to observation until the deformity shows signs of significant aggravation. The purpose of this analysis is to explore whether the concave-convex biases associated with scoliosis (local degeneration of the intervertebral discs, nucleus migration, and local increase in trabecular bone-mineral density of vertebral bodies) may be identified as progressive risk factors. Finite element models of a 26 degrees right thoracic scoliotic spine were constructed based on experimental and clinical observations that included growth dynamics governed by mechanical stimulus. Stress distribution over the vertebral growth plates, progression of Cobb angles, and vertebral wedging were explored in models with and without the biases of concave-convex properties. The inclusion of the bias of concave-convex properties within the model both augmented the asymmetrical loading of the vertebral growth plates by up to 37% and further amplified the progression of Cobb angles and vertebral wedging by as much as 5.9 degrees and 0.8 degrees, respectively. Concave-convex biases are factors that influence the progression of scoliotic curves. Quantifying these parameters in a patient with scoliosis may further provide a better clinical assessment of the risk of progression. [ABSTRACT FROM AUTHOR]