Quantifying Riverbed Sediment Using Recreational-Grade Side Scan Sonar

The size and organization of bed material, bed texture, is a fundamental attribute of channels and is one component of the physical habitat of aquatic ecosystems. Multiple discipline-specific definitions of texture exist and there is not a universally accepted metric(s) to quantify the spectrum of possible bed textures found in aquatic environments. Moreover, metrics to describe texture are strictly statistical. Recreational-grade side scan sonar systems now offer the possibility of imaging submerged riverbed sediment at resolutions potentially sufficient to identify subtle changes in bed texture with minimal cost,expertise in sonar, or logistical effort. However, inferring riverbed sediment from side scan sonar data is limited because recreational-grade systems were not designed for this purpose and methods to interpret the data have relied on manual and semi-automated routines. Visual interpretation of side scan sonar data is not practically applied to large volumes of data because it is labor intensive and lacks reproducibility. This thesis addresses current limitations associated with visual interpretation with two objectives: 1) objectively quantify side scan sonar imagery texture, and 2) develop an automated texture segmentation algorithm for broad-scale substrate characterization. To address objective 1), I used a time series of imagery collected along a 1.6 km reach of the Colorado River in Marble Canyon, AZ. A statistically based texture analysis was performed on georeferenced side scan sonar imagery to identify objective metrics that could be used to discriminate different sediment types. A Grey Level Co-occurrence Matrix based texture analysis was found to successfully discriminate the textures associated with different sediment types. Texture varies significantly at the scale of ≈ 9 m2 on side scan sonar imagery on a regular 25 cm grid. A minimum of three and maximum of five distinct textures could be observed directly from side scan sonar imagery. To address objective 2), linear least squares and a Gaussian mixture modeling approach were developed and tested. Both sediment classification methods were found to successfully classify heterogeneous riverbeds into homogeneous patches of sand, gravel, and boulders. Gaussian mixture models outperformed the least squares models because they classified gravel with the highest accuracies.Additionally, substrate maps derived from a Gaussian modeling approach were found to be able to better estimate reach averaged proportions of different sediments types when they were compared to similar maps derived from multibeam sonar

Violence Against Women: Synthesis of Research on Offender Interventions

This report provides an overview of the latest research on interventions for men who assault women—wives, girlfriends, and acquaintances. The assaults may be physical or sexual, and they almost always involve psychological abuse. The overview begins with a description of the major components of current programs and then describes what is known about effective assessment and treatment methods. Several topics are covered that are often of interest to practitioners, including methods for enhancing treatment motivation, assessment of dangerousness, and culturally competent practice. The role of research in resolving controversial issues and the characteristics of sound evaluations are also discussed. Programs reviewed will be those commonly labeled as “social service,” “treatment,” and “psycho-educational,” as opposed to purely criminal justice interventions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88208/1/Violence_Against_Women-_Synthesis of Resarch_on_Offender_Interventions-Saunders+Hamill-NCJ201222.pd

Alluvial Substrate Mapping by Automated Texture Segmentation of Recreational-Grade Side Scan Sonar Imagery

Side scan sonar in low-cost ‘fishfinder’ systems has become popular in aquatic ecology and sedimentology for imaging submerged riverbed sediment at coverages and resolutions sufficient to relate bed texture to grain-size. Traditional methods to map bed texture (i.e. physical samples) are relatively high-cost and low spatial coverage compared to sonar, which can continuously image several kilometers of channel in a few hours. Towards a goal of automating the classification of bed habitat features, we investigate relationships between substrates and statistical descriptors of bed textures in side scan sonar echograms of alluvial deposits. We develop a method for automated segmentation of bed textures into between two to five grain-size classes. Second-order texture statistics are used in conjunction with a Gaussian Mixture Model to classify the heterogeneous bed into small homogeneous patches of sand, gravel, and boulders with an average accuracy of 80%, 49%, and 61%, respectively. Reach-averaged proportions of these sediment types were within 3% compared to similar maps derived from multibeam sonar

MENSTRUAL CYCLE AND FRONTAL KNEE LOADING DURING A CUTTING MANOEUVRE – A PILOT STUDY

The aim of this study was to compare the knee internal adduction moment during an unanticipated cutting manoeuvre in different phases of the menstrual cycle. Data were collected using a motion capture system integrated with a force platform. The knee internal adduction moment of four young women were compared in menstrual and ovulation phase of the menstrual cycle. The results of this study showed that knee internal adduction moment is higher in the time of ovulation phase and may increase the potential risk for noncontact ACL injury during this phase of the menstrual cycle. These results could affect the development of training schedules for women athletes

THE RELATIONSHIP BETWEEN ACHILLES TENDON DIMENSIONS AND FOOT STRIKE INDEX IN REARFOOT AND NON-REARFOOT RUNNERS

The purpose of this study was to describe the relationship between Achilles tendon dimensions and foot strike index in rearfoot and non-rearfoot runners. 107 recreational runners were divided into a group of rearfoot (n = 88) and a group of non-rearfoot runners (n = 19). Achilles tendon dimensions were measured by a combination of ultrasonography imaging and kinematic analysis. To analyse the footfall pattern, each participant performed 8 successful trials of running at their stated self-preferred endurance speed. Partial correlation was used for statistical analysis. Runners in the group of non-rearfoot runners, whose footfall pattern is more over forefoot, have a longer and thinner Achilles tendon

Strategies for a self-selected unanticipated cutting maneuver and the risk for ACL injury: Findings from HAIE study

The purpose of the study was twofold: 1) to qualitatively investigate the different change of direction (COD) strategies used by females in an ecological situation; and 2) to evaluate the knee internal adduction moment and knee flexion during the first 30% of support as risk factors for anterior cruciate ligament (ACL) injury during these strategies. Ninety-four females, classified in ACTIVE and NON-ACTIVE groups performed five trials of a COD maneuver that were subsequently qualitatively evaluated. Kinematic and ground reaction force data were analyzed in the first 30% of support. To assess differences between strategies, we used a two-way repeated measures analysis of variance. Four strategies of 45° COD maneuvers were found. The different strategies involved either a cross-over with the right or left leg or had no cross-over. The statistical analysis revealed significant differences with a lesser knee internal adduction moment (p<.05) and a greater knee flexion angle during the strategies with a cross-over of the right foot compared to the other strategies (p<.05). Therefore, it is important to consider the potential effect of different strategies on ACL injury risk factors, as ACL injury risk factors may vary depending on the specific directional technique used

"It is very difficult in this business if you want to have a good conscience": pharmaceutical governance and on-the-ground ethical labour in Ghana

The governance of pharmaceutical medicines entails complex ethical decisions that should, in theory, be the responsibility of democratically accountable government agencies. However, in many Low- and Middle-Income Countries (LMICs), regulatory and health systems constraints mean that many people still lack access to safe, appropriate and affordable medication, posing significant ethical challenges for those working on the “front line”. Drawing on 18 months of fieldwork in Ghana, we present three detailed case studies of individuals in this position: an urban retail pharmacist, a rural over-the-counter medicine retailer, and a local inspector. Through these case studies, we consider the significant burden of “ethical labour” borne by those operating “on the ground”, who navigate complex moral, legal and business imperatives in real time and with very real consequences for those they serve. The paper ends with a reflection on the tensions between abstract, generalised ethical frameworks based on high-level principles, and a pragmatic, contingent ethics-in-practice that foregrounds immediate individual needs – a tension rooted in the gap between the theory and the reality of pharmaceutical governance that shifts the burden of ethical labour downwards and perpetuates long-term public health risks

FOOTFALL PATTERN DURING RUNNING IN PRESCHOOL CHILDREN ACCORDING TO AGE AND FOOTWEAR

The aim of this study was to compare the footfall pattern (FP) in different age groups of preschool children while they ran in standard running shoes (SRS) and barefoot. Forty-eight children aged 3-6 years participated in the study and were split into 4 age groups (n=12). All children performed a simple running game (based on the shuffle run) in SRS and barefoot. The length of the runway was adjusted for each age group. Kinematic and kinetic data were collected using 3-D motion capture system. We analyzed strike index (SI) and sagittal plane ankle angle (AA) at initial contact (IC) from 6 successful running trials for each child in each condition. We found differences between conditions in both SI (p=0.000, η2=0.448) and AA (p=0.000, η2=0.259) respectively, but we did not find any differences among age groups. Moreover, we found an interaction between age and conditions in AA (p=0.019, η2= 0.201). In preschool children, FP changed differently in certain age groups according to the footwear condition

LANDING PATTERNS AFTER BLOCK IN VOLLEYBALL: APLICATION FOR ACL INJURY

The aim of the present study was to describe landing patterns during initial phase (0-30° knee flexion) of “go” landing after block in volleyball. Nineteen elite female volleyball players served as participants in this study. Eight infrared cameras and two force platforms were employed to collect the kinematic and kinetic data. The players used four different landing patterns during initial phase of the “go” landing after block. The players landed with different knee angle positions at initial contact depending on landing pattern. Results of the current study generally suggest that players may protect the ACL during the initial phase of landing by decreasing knee frontal plane angle and moment in direction from valgus to varus position

TRENDELENBURG TEST AND ACL RISK FACTORS DURING UNANTICIPATED CUTTING MANOEUVRE – A PILOT STUDY

The aim of this study was to find differences between the Trendelenburg test and risk factors for an ACL injury during a cutting manoeuvre in two age groups. Six female athletes divided into two groups (n3x2) participated in this study. Ten infrared cameras and force platform were used to collect the kinematic and kinetic data. The results of this pilot study suggest no hip weakness was observed in either group. The younger group had a larger difference between starting and finishing position during TT. In other side we found the higher values of the ACL risk factors in the older group