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Odontoidectomy for ventral compressive pathology may result in O-C1 and/or C1-2 instability. Same-stage endonasal C1-2 spinal fusion has been advocated to eliminate risks associated with separate-stage posterior approaches. While endonasal methods for C1 instrumentation and C1-2 trans-articular stabilization exist, no hypothetical construct for endonasal occipital instrumentation has been validated. We provide an anatomic description of anterior occipital condyle (AOC) screw endonasal placement as proof-of-concept for endonasal craniocervical stabilization.Eight adult, injected cadaveric heads were studied for placing 16 AOC screws endonasally. Thin-cut CT was used for registration. After turning a standard inferior U-shaped nasopharyngeal flap endonasally, 4 mm × 22 mm AOC screws were placed with a 0° driver using neuronavigation. Post-placement CT scans were obtained to determine: site-of-entry, measured from the endonasal projection of the medial O-C1 joint; screw angulation in sagittal and axial planes, proximity to critical structures.Average site-of-entry was 6.88 mm lateral and 9.74 mm rostral to the medial O-C1 joint. Average angulation in the sagittal plane was 0.16° inferior to the palatal line. Average angulation in the axial plane was 23.97° lateral to midline. Average minimum screw distances from the jugular bulb and hypoglossal canal were 4.80 mm and 1.55 mm.Endonasal placement of AOC screws is feasible using a 0° driver. Our measurements provide useful parameters to guide optimal placement. Given proximity of hypoglossal canal and jugular bulb, neuronavigation is recommended. Biomechanical studies will ultimately be necessary to evaluate the strength of AOC screws with plate-screw constructs utilizing endonasal C1 lateral mass or C1-2 trans-articular screws as inferior fixation points.

This study examines the potential relationship between eating disorders and antisocial behaviors through the lenses of the general theory of crime and general strain theory. We utilized the data from the National Longitudinal Study of Adolescent to Adult Health, a longitudinal study of a nationally representative sample of juveniles in grades 7 to 12 in the United States between 1994 and 2008. We constructed three separate measures of eating disorders and examined their relationships with both petty theft and aggressive behaviors. Results indicated that previous traumatic experiences (such as sexual abuse) are consistent risk factors for eating disorders, and that eating disorders can increase antisocial involvements. Moreover, eating disorders can diminish self-control and agitate depressed moods, which may increase the likelihood of both petty theft and violent conduct, and this effect can extend to later adulthood as well.

In many agricultural regions the human use of water from irrigation is often ignored or poorly represented in land surface models and operational forecasts. Because irrigation increases soil moisture, the feedbacks to surface energy balance, rainfall recycling, and atmospheric dynamics are not represented and may lead to reduced model skill. In this work, we describe four plausible and relatively simple irrigation routines that can be coupled to the next generation of hyper-resolution LSMs operating at scales of 1 km or less. The irrigation output from the four routines (crop model, precipitation delayed, evapotranspiration replacement, and vadose zone model irrigation based) are compared against a historical field scale irrigation database (2008–2014) from a 35 km2 study area under maize production and center pivot irrigation in western Nebraska (USA). Here we find the most conservative irrigation routine (crop model) produces seasonal totals of irrigation that compare well against the observed irrigation amounts across a range of wet and dry years but with a low bias of 80 mm yr−1. The most aggressive water savings irrigation routine (vadose zone model) indicates a potential irrigation savings of 120 mm yr−1 and yield losses of less than 3 % against the crop model benchmark and historical averages. The results from the various irrigation routines offer insights to local water managers about the potential value of water savings technologies and irrigation practices. Moreover, the routines offer the hyper-resolution LSM community a range of irrigation routines to better constrain irrigation decision making at critical temporal (daily) and spatial scales (