Toward improved prediction of the bedrock depth underneath hillslopes: Bayesian inference of the bottom‐up control hypothesis using high‐resolution topographic data

The depth to bedrock controls a myriad of processes by influencing subsurface flow paths, erosion rates, soil moisture, and water uptake by plant roots. As hillslope interiors are very difficult and costly to illuminate and access, the topography of the bedrock surface is largely unknown. This essay is concerned with the prediction of spatial patterns in the depth to bedrock (DTB) using high‐resolution topographic data, numerical modeling, and Bayesian analysis. Our DTB model builds on the bottom‐up control on fresh‐bedrock topography hypothesis of Rempe and Dietrich (2014) and includes a mass movement and bedrock‐valley morphology term to extent the usefulness and general applicability of the model. We reconcile the DTB model with field observations using Bayesian analysis with the DREAM algorithm. We investigate explicitly the benefits of using spatially distributed parameter values to account implicitly, and in a relatively simple way, for rock mass heterogeneities that are very difficult, if not impossible, to characterize adequately in the field. We illustrate our method using an artificial data set of bedrock depth observations and then evaluate our DTB model with real‐world data collected at the Papagaio river basin in Rio de Janeiro, Brazil. Our results demonstrate that the DTB model predicts accurately the observed bedrock depth data. The posterior mean DTB simulation is shown to be in good agreement with the measured data. The posterior prediction uncertainty of the DTB model can be propagated forward through hydromechanical models to derive probabilistic estimates of factors of safety.Key Points:We introduce an analytic formulation for the spatial distribution of the bedrock depthBayesian analysis reconciles our model with field data and quantifies prediction and parameter uncertaintyThe use of a distributed parameterization recognizes geologic heterogeneitiesPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137555/1/wrcr22005.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137555/2/wrcr22005_am.pd

Scapular winging: anatomical review, diagnosis, and treatments

Scapular winging is a rare debilitating condition that leads to limited functional activity of the upper extremity. It is the result of numerous causes, including traumatic, iatrogenic, and idiopathic processes that most often result in nerve injury and paralysis of either the serratus anterior, trapezius, or rhomboid muscles. Diagnosis is easily made upon visible inspection of the scapula, with serratus anterior paralysis resulting in medial winging of the scapula. This is in contrast to the lateral winging generated by trapezius and rhomboid paralysis. Most cases of serratus anterior paralysis spontaneously resolve within 24 months, while conservative treatment of trapezius paralysis is less effective. A conservative course of treatment is usually followed for rhomboid paralysis. To allow time for spontaneous recovery, a 6–24 month course of conservative treatment is often recommended, after which if there is no recovery, patients become candidates for corrective surgery

Examining elementary students\u27 perceptions of engineers

There has been a national focus on improving K-12 Science, Technology, Engineering, and Mathematics (STEM) education. The integration of engineering education from kindergarten through high school (K-12) has been identified as key to sustaining the U.S. economy and standard of living. Misconceptions about the nature of engineering may deter children from even considering this profession. Currently, there are few research studies on young children\u27s perceptions of engineers, and such research can be used to support children along STEM pathways. The purpose of this research was to investigate elementary students’ perceptions of engineers for children enrolled in a gifted and talented outreach program. Participants included students enrolled in two structural engineering classes: one for 3rd and 4th graders and another for 5th and 6th grade students. Participants represented an age group that is not typically exposed to engineering. This research was framed within a constructivist theoretical framework, and qualitative research methods were utilized to develop a rich understanding of the perspectives of students enrolled in the engineering classes. Data collection included student pre- and post-questionnaires, Draw-an-Engineer tasks, and semi-structured interviews. Data analysis entailed the use of open and axial coding. Trustworthiness of data was determined through triangulation of multiple data sources. Results demonstrated how children describe the work of engineers, objects associated with engineering, tools used or created by engineers, and professional characteristics of engineers. In addition, images of engineers were discussed and influences on students’ perceptions of engineers were identified. The findings of this study have implications for the development of formal and informal K-12 curricula and programs that focus on improving students\u27 understanding and engagement in engineering. Implications for researchers interested in studying children’s perceptions were also discussed

Ramp Metering and High Occupancy Vehicle Facilities: A Synthesis Study

High Occupancy Vehicle (HOV) lanes and ramp metering have been implemented at several places in the country to improve traffic conditions on freeways. This report presents a comprehensive study of the state of the art and state of the practice of these facilities in the U.S. and their effectiveness in improving traffic conditions on the freeway. The various types of HOV facilities have been discussed along with other system components such as park-and-ride facilities, ridership programs, enforcement areas and policies, ingress/egress facilities. The cost of several HOV facilities in the country has been presented and a set of guidelines have been prepared that may be followed for the implementation of a HOV Lane Facility. A comprehensive review of the various ramp metering facilities in the country has been presented. The components of the ramp metering system, the physical infrastructure and the various classifications of the ramp metering algorithms have been discussed. The results of a feasibility study for the implementation of these facilities on I-70 in Indianapolis, between I-65 and I-465 have also been presented