Ultrasoundassisted unusual body extraction USAFE Overview of method and complex pearls
Performing an osteotomy with a surgical mallet and an osteotome is a delicate intervention mostly based on the surgeon proprioception. It remains difficult to assess the properties of bone tissue being osteotomized. Mispositioning of the osteotome or too strong impacts may lead to bone fractures which may have dramatic consequences. The objective of this study is to determine whether an instrumented hammer may be used to retrieve information on the material properties around the osteotome tip. A hammer equipped with a piezoelectric force sensor was used to impact 100 samples of different materials and thicknesses. A model-based inversion technique was developed based on the analysis of two indicators derived from the analysis of the variation of the force as a function of time in order to i) classify the samples depending on their material types, ii) determine the materials stiffness and iii) estimate the samples thicknesses. The model resulting from the classification using Support Vector Machines (SVM) learning techniques can efficiently predict the material of a new sample, with an estimated 89% prediction performance. A good agreement between the forward analytical model and the experimental data was obtained, leading to an average error lower than 10% in the samples thickness estimation. Based on these results, navigation and decision-support tools could be developed and allows surgeons to adapt their surgical strategy in a patient-specific manner. Copyright (c) 2020 by ASME.Phyllosphere harbors diverse microorganisms, which influence plant growth and health. In order to understand the extent to which environmental factors affect epiphytic microbial communities, we characterized microbial communities on leaves of three separate tree species present on the college campus, and also present within a forest park over two seasons. Quantitative PCR analysis showed the quantity of 16S rRNA genes was lower in May compared with October, while the abundances of functional genes (nifH and bacterial amoA genes) were extremely high in May. High-throughput sequencing revealed a large variation in the diversity and composition of bacterial and diazotrophic communities over the two seasons, and showed the abundance of functional genera, such as Nocardioides, Bacillus and Zoogloea were significantly elevated in May. In addition, xenobiotic biodegradation pathways of bacterial communities were clearly elevated in May. Network analysis showed the correlations between phyllospheric bacteria in May were more complex than that in October and showed greater negative correlations. These results were consistent in all tree species in this study. This study showed that phyllospheric bacteria varied greatly in different seasons, which implies that different growing seasons should be considered in the exploitation of the interactions between phyllospheric microorganisms and host plants. © FEMS 2020.Transferring sows and their litters to group lactation (GL) after an initial period of farrowing crate (FC) housing could enhance the viability of GL for commercial production. Group lactation from 7 d postpartum would reduce the time sows spend in confinement, but the effects of early mixing on animal welfare and productivity require examination. Two experiments were conducted on sows and piglets kept in GL from 7, 10, or 14 d postpartum, compared with FC. Experiment 1 utilized 180 sows and 1,887 piglets over five time replicates (n = 60 sow and litter units per treatment) comparing GL from 7 or 14 d postpartum to FC. In experiment 2, 108 sows and 1,179 piglets were studied over three time replicates (n = 36 sow and litter units per treatment) comparing GL from 10 or 14 d postpartum to FC. All sows farrowed in FC. Group lactation sows were transferred to pens (one pen of five sows at 8.4 m2/sow and one pen of seven sows at 8.1 m2/sow, per GL treatment and replicate) with their litters at 7 (GL7), 10 (GL10), ence. All rights reserved. For permissions, please e-mail [email protected] International Society of Biomechanics (ISB) has proposed standardized recommendations for recording human joint motion. The Euler angles-the orientation representation currently proposed by the ISB-has two drawbacks, namely the issue of singularities (gimbal lock) and the difficulty to obtain clinical and interpretable orientation representation for compound movements. The orientation representation of the shoulder joint with the Euler angles is particularly challenging due to its broad range of motion. This paper proposes and evaluates an alternative orientation representation for shoulder movement based on the Tilt-and-Torsion representation, a method that aims at providing a more clinically interpretable solution for describing joint movements compared to the standard Euler angles. METHODS Three studies were performed to compare the different orientation representation methods. The first two studies consist in simulations of arm elevation in different planes. The third study is an experiment using inertial-measurement-units with one test subject performing shoulder elevation movements in different planes. check details The Tilt-and-Torsion representation is then compared with different Euler angle conventions. RESULTS The results show that Euler angles are biased or clinically uninterpretable for compound movements. Conversely, Tilt-and-Torsion representation does not suffer from these limitations. DISCUSSION Although not extensive, the experiments suggests that the Tilt-and-Torsion representation has the potential to better represent human movements and provide more clinically interpretable results than the Euler angles. Copyright (c) 2020 by ASME.Ballet dancers have finite careers due to the demands placed upon their bodies throughout years of training, study, and performance. The average age a dancer retires is thirty-four due to persistent stress on their joints and injuries due to mechanical overload or overuse. Proper form is crucial to prevent injury. The aim of the study was to establish benchmarks for normal movement patterns amongst professional dancers. Ten professional ballerinas were studied. Reflective markers were placed on the pelvis, left and right anterior superior iliac spine (ASIS) and posterior iliac spine (PSIS) to evaluate motion during Barre movements plié, grand battement, and développé. Pelvis flexion/extension, mediolateral rotation, and torsion were analyzed. These motions test different skills. The plié is a controlled coordinated motion using both legs. The grand battement and développé both require leg extension, one with a quick motion that creates momentum and one using controlled motion that requires strength. Each requires core and pelvis stability to perform accurately and with less injury.