Differences in the biomechanical response between healthy and low back pain patients from a isometric extension test

Purpose: To compare, in healhty subjects and low back pain patients, the erector spinal muscle response in a máximum isometric contraction intensities using simultaneously electromyography and ultrasonography. Participants: 59 subjects: 33 Healthy persons (45% ♀). 26 LBP patients (39% ♀) with a mean age of 30.39 (±7.785). Methods: Cross sectional study. Participants, following a maximal strength test as measured by a load cell, perform an isometric contraction of maximum strength. From sitting, each subject develops a maximum isometric lumbar extension, locked at 45 degrees from vertical. The hip and this of the subject were attached by a strap. After preliminary training, each subject performed three repetitions of described gesture resting for a minute and a half between each attempt. Records were taken throughout the maximum contraction, EMG signal and a ultrasonography image, for each ES (right and left). Measured torque, inclination angle, thickness and electromyography activation (MVC). Analysis: We performed a descriptive analysis of both groups and subsequently made T-Student test for independent data in each of the variables measured. Results: Mean values for groups of healthy subjects and low back pain patients were, respectively: Torque: 61.652 (±20.137); 70.298 (±25.053). Right Angle: 6.48 (±2.181); 7.15 (±2.53). Left Angle: 5.36 (±2.26); 6.38 (±1.86). Right Thickness: 0.031 (±0.005); 0.033 (±0.008). Left Thickness: 0.032 (±0.006); 0.034 (±0.006). Right MVC: 558.64 (±211.029); 576.15 (±267.69). Left MVC: 589.21 (±257.739); 671.15 (±370.722). No significant differences were found in any variable when comparing the results between healthy subjects and low back pain patients. Torque: −8.65 (±9.02) (p = 0.347). Angle: Right: −0.659 (±0.613) (p = 0.280); Left: −1.021 (±0.549) (p = 0.068). Thick-ness: Right: 0.00 (±0.00) (p=0.259); Left: 0.00 (±0.00) (p=0.069). MVC: Right: -17.52 (±62.29) (p=0.780). Left: −81.84 (±81.91) (p = 0.321). Conclusions: Knowing how the erector spinal muscle behaves in a isometric back extension test, noting that biomechanically there are not significant differences in the responses with respect to a healthy subject, physical therapists could perform planning treatment which is the biopsychosocial model supported by the biomechanical model.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Reliability and parameterization of Romberg Test in people who have suffered a stroke

AIM: To analyze the reliability and describe the parameterization with inertial sensors, of Romberg test in people who have had a stroke. METHODS: Romberg's Test was performed during 20 seconds in four different setting, depending from supporting leg and position of the eyes (opened eyes / dominant leg; closed eyes / dominant leg; opened eyes / non-dominant leg; closed eyes / non-dominant leg) in people who have suffered a stroke over a year ago. Two inertial sensors (sampling frequency 180Hz) were placed in lumbar (L5-S1) and in the trunk (T7). The test was performed three times for the four different settings. The outcome variables were extracted in each of the axes (X, Y, Z) (figure 1). We considered as the maximum, minimum and mean velocity and the magnitude of the angular displacement for each of the sensors (Figure 2 shows an example of direct extraction of variables). Statistical Analysis: descriptive analysis of all outcome variables for each axis and sensor. Further analysis of the internal consistency of the measure was performed by analysis interclass correlation (ICC) with a confidence interval of 95%. RESULTS: Values obtained after statistical analysis show levels of reliability ranging from 0.61 (Z axis speed - eyes closed / nondominant leg) and 0.92 (Y axis offset - opened eyes / dominant leg). The descriptive results of all outcome variables are shown in Table 1. CONCLUSION: Making inertial sensors in trunk and / or lumbar, inertial sensors are reliable tools for parameterizing Romberg test in different settings in people who have suffered stroke over a year ago.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Parameterisation and reliability of the functional reach test in people who suffer stroke

AIM: The aim of this study is to analyse the reliability, sensitivity and specificity of the parameterisation of FRT using inertial sensors to record kinematic variables in subjects who have had a stroke. Our hypothesis is that the IS will be reliable instruments for kinematic study of the FRT. METHODS: This is a cross-sectional study of 5 subjects over 65 years who suffer of stroke. During the execution of Funtional Reach Test the subjects carried two inertial sensors, one was placed in the lumbar and the other in the trunk. After analysing the data obtained in the kinematic registration by inertial sensors a number of direct and indirect variables were obtained. The variables extracted directly from FRT through the IS were distance, maximun angular lumbosacral/thoracic displacement, time maximun angular lumbosacral/thoracic displacement, time return starting position and total time. Using this data the speed and the acceleration of each one of them were calculated. A descriptive analysis of all kinematic outcomes recorded by the two inertial sensors was developed (trunk and lumbar) and the average range achieved in the FRT. Reliability measures were calculated by analysing the internal consistency the measures with 95% confidence interval of each outcome variable. The reliability was calculated in the functional reach and the outcomes measured by the IS. RESULTS: The values in the the Functional Reach Test obtained in the present study (2.06 ± 12.75cm) are similar to those obtained in other studies with this population and in the same age range. Intrasubject reliability values observed in the use of inertial sensors are all located above 0.820, ranging from 0.829 (time B_C lumbar area) and 0.891 (A_B displacement of the trunk). Likewise, the observed intersubject values range from 0.821 (Time B_C lumbar area) and 0.883 (B_C trunk displacement). On the other hand, the reliability of the FRT was 0.987 (0.983-0.992) and 0.983 (0.979-0.989) intersubject and intrasubject respectively. CONCLUSION: The main conclusion that can be reached is that the inertial sensors are a tool with excellent reliability, validity, sensitivity and specificity in the parameterisation of the Functional Reach Test in people who have had a stroke.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Stereoselective Synthesis of Nojirimycin α-C-Glycosides from a Bicyclic Acyliminium Intermediate: A Convenient Entry to N,C-Biantennary Glycomimetics

A simple and efficient method for the stereoselective synthesis of nojirimycin α-C-glycoside derivatives has been developed using a bicyclic carbamate-type sp2-iminosugar, whose preparation on a gram scale has been optimized, as the starting material. sp2-iminosugar O-glycosides or anomeric esters serve as excellent precursors of acyliminium cations, which can add nucleophiles, including C-nucleophiles. The stereochemical outcome of the reaction is governed by stereoelectronic effects, affording the target α-anomer with total stereoselectivity. Thus, the judicious combination of C-allylation, carbamate hydrolysis, cross-metathesis, and hydrogenation reactions provides a very convenient entry to iminosugar α-C-glycosides, which have been transformed into N,C-biantennary derivatives by reductive amination or thiourea-forming reactions. The thiourea adducts undergo intramolecular cyclization to bicyclic iminooxazolidine iminosugar α-C-glycosides upon acid treatment, broadening the opportunities for molecular diversity. A preliminary evaluation against a panel of commercial glycosidases validates the approach for finely tuning the inhibitory profile of glycomimetics.España MCIN/AEI/10.13039/ 501100011033Unión Europea ERDF A way of making Europe” (grant nos. PID2019-105858RB-I00 and RTI2018-097609-B-C21)Junta de Andalucía (Grant number P20_00166

Inter-rater and intra-rater reliability of the extended TUG test in elderly participants

Background: To analyse the reliability, variance and execution time of the Extended Timed Up and Go (Extended TUG) test in three age groups of elderly participants (G1: 55–64 years; G2: 65–74 years; G3: 75–85 years). Methods: An analytical cross-sectional study of 114 recruited participants (63 women) of average age 70.17 (± 7.3) years was undertaken. Each participant performed the Extended TUG three consecutive times, with a rest break between tests of 120 s. Both the intragroup and intergroup reliability of the measurements in the Extended TUG were analysed. Results: The reliability of the Extended TUG test is excellent for the first and second decades but drops down to good for the third decade. Specifically, intragroup reliability ranged from 0.784 for G3 to 0.977 for G1 (G2 = 0.858). Intergroup reliability, compared with intragroup reliability, was slightly lower, ranging between 0.779 for G3 and 0.972 for G1 (G2 = 0.853). Conclusion: The reliability of the Extended TUG test progressively decreases with increasing age, being excellent for the younger age groups and good for the oldest age group

Biomechanical back disability index sonomyography-based: a new tool to identify risk of low back

Purpose: To analyze associations and contributions between architecture and muscle function variables during a back extension in a maximal isometric contraction. To develop an index to identify the risk of low back pain. Relevance: Identify predictors of the architecture and function of the back, particularly if such predictors are modifiable. Develop an index from a multivariate analysis to detect subjects at rick of low back pain. If such relationships exist and would create the index, then the effective intervention strategies could be used. Participants: 66 subjects: 33 Healthy persons and 33 LBP patients (49% ♀) with a mean age of 30.39 (±7.785). Methods: The subjects performed a maximal isometric strength test from which, through the use of sonomyography and electromyography, six variables were obtained: inclination angle and thickness of the erector spinal muscle fibers left and right, by ultrasound scan and muscle activation level (MVC) using EMGs. Analysis: A multiple regression was conducted to examine the relationship between the variables torque, architecture and muscle function. Discriminant analysis was performed. The grouping variable was the value of RMQ greater than or equal to 6. A logistic regression was calculated, with the variables of muscle architecture and activation level, during a maximal isometric contraction. The standardized scores of the variables included in the regression were used to develop the new index, a summative continuous scale assessing the risk of low back pain. Results: Multiple regression models explained between 60 and 86% of the variance in torque (Newton)for the lumbar extension. Linear discrimination ratios were: Angle: right (0.407); left (-0177). Thickness: Right (23.913); Left (59.775). The new index showed a good validity in the assessment of low back pain (area under the Receiver Operating Characteristic curve) with a ratio of 0.844. Conclusions: These findings suggest that it would be possible predicting the risk of low back pain from biomechanical variables. We suggest say that the Biomechanical Back Disability Index sonomyography-based is presented as a tool that can be used to indetify subjects with risk of low back pain.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Contribution in the foot health status in elderly people based on the results of biomechanics gait analysis

Purpose: To examine the correlation between the gait biomechanic analysis, foot dynamometry movements and different variables about the foot health status in elderly people. Relevance: Exact knowledge of the biomechanics of foot-print using this tool, as well as the relationship with the function and health status of the foot are important for planning the rehabilitation of the musculo skeletal pathology of the foot. Participants: 22 participants over 60 years old were recruited for a physical activity program. Methods: The variables were about anthropometric characteristics, about general and foot health status by FHSQ questionnaire scores ( foot pain, foot function, participant shoes, general health, physical activity, social capacity and vigour), about biomechanic gait analysis ( maximum pressures retro, mid and front foot, pressures times, times to initiate and end supports, maximum average pressures) and about analogue dynamometry variables in differente foot movements. Analysis: We used Pearson’s linear correlation with 95% Zr and a multivariant correlation. We looked for simple and multiple regression models. Results: the Pearson´s linear correlation showed relationships between foot pain variable with ending support in mid right foot variable (r = 0.562), maximum average pressure in mid right foot (r = 0.424), maximum average time pressure in front right foot (r = 0.588) and first right foot finger flexion (r = 0.434). A multivariant correlation was performed using the foots physical components of the FHSQ questionnaire scores how to dependent variable (foot pain) and the most relevant independents variables; ending support in mid right foot, maximum average time pressure in front right foot, first right foot finger flexion (r2 = 0.484; p < 0.007). Conclusions: We determined a significant quantitative relationship between biomechanics gait analysis, right foot dynamometry movements and the foot health status.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Evacuation management system for major disasters

Predicting and understanding mass evacuations are important factors in disaster management and response. Current modelling approaches are useful for planning but lack of real-time capabilities to help informed decisions as the disaster event evolves. To address this challenge, a real-time Evacuation Management System (EMS) is proposed here, following a stochastic approach and combining classical models of low complexity but high reliability. The EMS computes optimal assembly points and shelters and the related network of evacuation routes using GIS-based traffic, pedestrian and routing models including damaged assets or impassable areas. To test the proper operation performances of the EMS, we conducted a case study for the Gran Canaria wildfireThis research and APC was funded by the European Union’s H2020 research and innovation programme under grant agreement No. 832576 (ASSISTANCE project)

Goodness-of-fit tests for the functional linear model based on randomly projected empirical processes

We consider marked empirical processes indexed by a randomly projected functional covariate to construct goodness-of-fit tests for the functional linear model with scalar response. The test statistics are built from continuous functionals over the projected process, resulting in computationally efficient tests that exhibit root-n convergence rates and circumvent the curse of dimensionality. The weak convergence of the empirical process is obtained conditionally on a random direction, whilst the almost surely equivalence between the testing for significance expressed on the original and on the projected functional covariate is proved. The computation of the test in practice involves calibration by wild bootstrap resampling and the combination of several p-values, arising from different projections, by means of the false discovery rate method. The finite sample properties of the tests are illustrated in a simulation study for a variety of linear models, underlying processes, and alternatives. The software provided implements the tests and allows the replication of simulations and data applications.Supported by projects MTM2014-56235-C2-2-P and MTM2017-86061-C2-2-P from the Spanish Ministry of Economy, Industry and Competitiveness. Supported by projects MTM2013-41383-P and MTM2016-76969-P from the Spanish Ministry of Economy, Industry and Competitiveness, and the European Regional Development Fund; project 10MDS207015PR from Dirección Xeral de I + D, Xunta de Galicia