The Patterns of Morphological Change During Intracerebral Hemorrhage Expansion: A Multicenter Retrospective Cohort Study

Objectives: Hemorrhage expansion (HE) is a common and serious condition in patients with intracerebral hemorrhage (ICH). In contrast to the volume changes, little is known about the morphological changes that occur during HE. We developed a novel method to explore the patterns of morphological change and investigate the clinical significance of this change in ICH patients.Methods: The morphological changes in the hematomas of ICH patients with available paired non-contrast CT data were described in quantitative terms, including the diameters of each hematoma in three dimensions, the longitudinal axis type, the surface regularity (SR) index, the length and direction changes of the diameters, and the distance and direction of movement of the center of the hematoma. The patterns were explored by descriptive analysis and difference analysis in subgroups. We also established a prognostic nomogram model for poor outcomes in ICH patients using both morphological changes and clinical parameters.Results: A total of 1,094 eligible patients from four medical centers met the inclusion criteria. In 266 (24.3%) cases, the hematomas enlarged; the median absolute increase in volume was 14.0 [interquartile range (IQR), 17.9] mL. The initial hematomas tended to have a more irregular shape, reflected by a larger surface regularity index, than the developed hematomas. In subtentorial and deep supratentorial hematomas, the center moved in the direction of gravity. The distance of center movement and the length changes of the diameters were small, with median values of less than 4 mm. The most common longitudinal axis type was anterior–posterior (64.7%), and the axis type did not change between initial and repeat imaging in most patients (95.2%). A prognostic nomogram model including lateral expansion, a parameter of morphological change, showed good performance in predicting poor clinical outcomes in ICH patients.Conclusions: The present study provides a morphological perspective on HE using a novel automatic approach. We identified certain patterns of morphological change in HE, and we believe that some morphological change parameters could help physicians predict the prognosis of ICH patients.

Modeling and analysis of an electro-magneto-elastic rotating cylindrical tube actuator

This paper presents the static modeling and analysis of a novel cylindrical tube actuator subjected to a rotation about longitudinal axis with an internally applied air pressure under an electromagnetic field. The current tube actuator belongs to a smart actuator category and is made of an electro-magneto-active polymer filled with a particular volume fraction of suitable fillers. A continuum mechanics-based electro-magneto-mechanical model is developed to predict the response of the actuator for a combined pressure and electromagnetic field loading. To validate the same, the model is compared with the outputs of an existing spring roll actuator. Parametric studies are subsequently performed for varying input pressure, electric field, magnetic field, fillers content, and actuator’s rotational speed. The output sensitivity in terms of strain intensity at inner and outer surfaces of the actuator is also checked at different controlling inputs. In addition, various electro-magneto-mechanical instability curves are drawn to examine the critical inflation of the tube actuator. In general, the developed model provides initial steps toward the modern actuator designs for applications where a precise control with high load-carrying capability of the actuator plays a significant role.

Effect of chord-wise flexibility in the lift generation of flapping MAV with membrane wing

Purpose The purpose of this study is to experimentally analyse the effect of flexible and stiffened membrane wings in the lift generation of flapping micro air vehicle (MAV). Design/methodology/approach This is analysed by the rectangle wing made up of polyethylene terephthalate sheets of 100 microns. MAV is tested for the free stream velocity of 2 m/s, 4 m/s, 6 m/s and k* of 0, 0.25, 1, 3, 8. This test is repeated for flapping MAV of the free flapping frequency of 2 Hz, 4 Hz, 6 Hz, 10 Hz and 12 Hz. Findings This study shows that the membrane wing with proper stiffeners can give better lift generation capacity than a flexible wing. Research limitations/implications Only a normal force component is measured, which is perpendicular to the longitudinal axis of the model. Practical implications In MAVs, the wing structures are thin and light, so the effect of fluid-structure interactions is important at low Reynold’s numbers. This data are useful for the MAV developments. Originality/value The effect of chord-wise flexibility in lift generation is the study of the effect of a flexible wing and rigid wing in MAV. It is analysed by the rectangle wing. The coefficient of normal force at different free stream conditions was analysed.

U-Net Modelling-Based Imaging MAP Score for Tl Stage Nephrectomy: An Exploratory Study

We evaluate the stability of the clinical application of the MAP scoring system based on anatomical features of renal tumour images, explore the relevance of this scoring system to the choice of surgical procedure for patients with limited renal tumours, and investigate the effectiveness of automated segmentation and reconstruction 3D models of renal tumour images based on U-net for interpretative cognitive navigation during laparoscopy Tl stage radical renal tumour cancer surgery. A total of 5 000 kidney tumour images containing manual annotations were applied to the training set, and a stable and efficient full CNN algorithm model oriented to clinical needs was constructed to regionalism and multistructure and to finely automate segmentation of kidney tumour images, output modelling information in STL format, and apply a tablet computer to intraoperatively display the Tl stage kidney tumour model for cognitive navigation. Based on a training sample of MR images from 201 patients with stage Tl renal tumour cancer, an adaptation of the classical U-net allows individual segmentation of important structures such as renal tumours and 3D visualisation to visualise the structural relationships and the extent of tumour invasion at key surgical sites. The preoperative CT and clinical data of 225 patients with limited renal tumours treated surgically at our hospital from August 2011 to August 2012 were retrospectively analysed by three imaging physicians using the MAP scoring system for the total score and the variables R (maximum diameter), E (exogenous/endogenous), N (distance from the renal sinus), A (ventral/dorsal), L (relationship along the longitudinal axis of the kidney), and h (whether in contact with the renal hilum). The score for each variable (contact with the renal hilum) was statistically compared with each other for the three observers. Patients were divided into three groups according to the total score—low, medium, and high—and according to the surgical procedure—radical and partial resection. The correlation between the total score and the score of each variable and the choice of surgical procedure was analysed. The agreement rate of the total score and the score of each variable for all three observers was over 90% ( P ≤ 0.001). The map scoring system based on the anatomical features of renal tumour imaging was well stabilized, and the scores were significantly correlated with the surgical approach.

Calculation features of compressed-bent build-up timber columns with nonlinear-deformable shear bracings

Object of research is build-up compressed–bent and eccentrically compressed columns on yielding nonlinear – deformable shear bracings. Purpose of the research is development of a numerical method for calculation of columns, allowing to take in account the influence of deflection of elastic axis of bar on the increment of the bending moment from the action of longitudinal compressive force and the nonlinear dependence between the forces and deformations in the shear bracings. Problem-solving method consists in dividing the column into separate sections, a system of equations is compiled from the condition of equality of the increment of concentrated shears. The loading process is divided into a set number of stages, at each forces in the shear bracings, the stresses in the branches, and the buckling function of the elastic axis of the element are determined. The obtained values of forces in the shear bracings and buckling are used to specify stiffness of the bracings and component of the bending moment arising due to eccentric application of the longitudinal compressive force when longitudinal axis of the element is deflecting. To obtain the resulting values, the obtained forces, deflections and stresses in the branches at each calculation stage are summed up.

A novel 3D-vision–based collaborative robot as a scope holding system for port surgery: a technical feasibility study

OBJECTIVE A clear, stable, suitably located vision field is essential for port surgery. A scope is usually held by hand or a fixing device. The former yields fatigue and requires lengthy training, while the latter increases inconvenience because of needing to adjust the scope. Thus, the authors innovated a novel robotic system that can recognize the port and automatically place the scope in an optimized position. In this study, the authors executed a preliminary experiment to test this system’s technical feasibility and accuracy in vitro. METHODS A collaborative robotic (CoBot) system consisting of a mechatronic arm and a 3D camera was developed. With the 3D camera and programmed machine vision, CoBot can search a marker attached to the opening of the surgical port, followed by automatic alignment of the scope’s axis with the port’s longitudinal axis so that optimal illumination and visual observation can be achieved. Three tests were conducted. In test 1, the robot positioned a laser range finder attached to the robot’s arm to align the sheath’s center axis. The laser successfully passing through two holes in the port sheath’s central axis defined successful positioning. Researchers recorded the finder’s readings, demonstrating the actual distance between the finder and the sheath. In test 2, the robot held a high-definition exoscope and relocated it to the setting position. Test 3 was similar to test 2, but a metal holder substituted the robot. Trained neurosurgeons manually adjusted the holder. The manipulation time was recorded. Additionally, a grading system was designed to score each image captured by the exoscope at the setting position, and the scores in the two tests were compared using the rank-sum test. RESULTS The CoBot system positioned the finder successfully in all rounds in test 1; the mean height errors ± SD were 1.14 mm ± 0.38 mm (downward) and 1.60 mm ± 0.89 mm (upward). The grading scores of images in tests 2 and 3 were significantly different. Regarding the total score and four subgroups, test 2 showed a more precise, better-positioned, and more stable vision field. The total manipulation time in test 2 was 20 minutes, and for test 3 it was 52 minutes. CONCLUSIONS The CoBot system successfully acted as a robust scope holding system to provide a stable and optimized surgical view during simulated port surgery, providing further evidence for the substitution of human hands, and leading to a more efficient, user-friendly, and precise operation.

Substantiation of the influence of changes in the coefficient of axle distribution of braking force on the handling of a passenger car

The article considers the change of the radius of the instantaneous center of rotation of a car moving along a curved trajectory during braking, taking into account the lateral input of the wheels of both axles of cars, both equipped with electronic tracking systems and not equipped with such. A criterion for assessing the controllability of cars moving on a curved trajectory in a braked state, by comparing the ratio of the current speed of the car to the longitudinal base with the ratio of the coefficients of lateral tire input to the product of the longitudinal base of the car, mass and cosines. It is established that the radius of instantaneous rotation of the longitudinal axis of the car moving along a curved trajectory during braking depends on the speed of the center of mass of the car, the coefficient of axle distribution of braking force, physical characteristics of applied tires, steering wheel angle and design and weight parameters. As a result, it allows you to set controllability. The authors obtained dependences that will create new algorithms for the operation of modern electronic control systems for stabilizing the longitudinal axis of a braked car, taking into account the speed of the car, its design and weight characteristics, the main characteristics of its braking system (coefficient of axle braking force distribution), physical characteristics used tires on wheels and connect them to the angles of the steered wheels, controlling the deviation of the longitudinal axis, which allows the driver to maintain the possibility of quite sharp maneuvers directly in the braking process, moving along a curved trajectory.

Aircraft Position Prediction during the Crosswind Approach

Testing the impact of the drag coefficient on an F16 aircraft model, depending on the angle of attack a was performed. First, a navigation model was introduced describing the preliminary and computational assumptions of the model. The final part of the present paper contains the relationships between the wind angle and the wind correction angle at the angle of attack a = 00, a = 110, a = 130 for a full-scale F-16 aircraft. The tables present results of all the calculations for individual angles of attack, taking into account variable wind angles relative to the longitudinal axis of the runway. The values show the corrections calculated for an 1/19 scale aircraft model and for a full-scale F16 aircraft. The "right" and "left" designations represent the direction from which the wind blows in relation to the aircraft.

Features of an elastic wheel motion along a curvilinear and rectilinear trajectory with a slip

The results of the study of the motion of an elastic wheel as an integral mechanism along a curvilinear and a rectilinear trajectory with a slip on the ground plane having a high adhesion coefficient are presented. The previous researches analysis has shown that the most complete theory of wheel skidless rolling without slipping on elastic pneumatics was formulated by Keldysh V. M. who proposed the equation for calculating the curvature of the motion trajectory. Due to the difficulty of this equation coefficients determining, its use is currently limited. In this paper, the dependences for determining the components of the equation of the elastic wheel motion trajectory curvature have been proposed. According to the shimmy theory, during an elastic wheel rolling along a curvilinear trajectory, the rim turn and its lateral displacement relative to the tire-ground contact patch occur simultaneously. The rim turn causes tire body torsion, and the lateral displacement causes the elastic wheel moving with a slip angle. It is established that the absolute value of the tire body torsion angle is equal to the slip angle, and their values depend on the trajectory curvature, on the tire-ground contact patch longitudinal axis, and on the existence of traction there. The condition, under which the tire body energy distribution on the rim relative rotation and on its lateral displacement during the movement along a curved trajectory is uniform, has been determined. The experimental confirmation of the hypothesis of uniform distribution of the energy supplied to the elastic wheel during its movement along a curvilinear trajectory on the rim relative turning and its lateral displacement has been obtained. When the elastic wheel moves along a rectilinear trajectory with a slip, only the rim lateral displacement occurs, this displacement is accompanied by a cornering force applied in the center of the tire-ground contact patch and by the tire alining torque relative to the vertical axis passing through the contact patch geometric center. The energy consumption for the rim lateral displacement during the wheel rolling along a rectilinear trajectory with a slip has been also determined. The results of the research can be useful to professionals improving the wheeled vehicles performance characteristics, including maneuverability, handling, and road stability.

Consciousness Detection on Injured Simulated Patients Using Manual and Automatic Classification via Visible and Infrared Imaging

In a disaster scene, triage is a key principle for effectively rescuing injured people according to severity level. One main parameter of the used triage algorithm is the patient’s consciousness. Unmanned aerial vehicles (UAV) have been investigated toward (semi-)automatic triage. In addition to vital parameters, such as heart and respiratory rate, UAVs should detect victims’ mobility and consciousness from the video data. This paper presents an algorithm combining deep learning with image processing techniques to detect human bodies for further (un)consciousness classification. The algorithm was tested in a 20-subject group in an outside environment with static (RGB and thermal) cameras where participants performed different limb movements in different body positions and angles between the cameras and the bodies’ longitudinal axis. The results verified that the algorithm performed better in RGB. For the most probable case of 0 degrees, RGB data obtained the following results: Mathews correlation coefficient (MMC) of 0.943, F1-score of 0.951, and precision-recall area under curve AUC (PRC) score of 0.968. For the thermal data, the MMC was 0.913, F1-score averaged 0.923, and AUC (PRC) was 0.960. Overall, the algorithm may be promising along with others for a complete contactless triage assessment in disaster events during day and night.