Autism has been largely portrayed as a psychiatric and childhood disorder. However, autism is a lifelong neurological condition that evolves over time through highly heterogeneous trajectories. These trends have not been studied in relation to normative aging trajectories, so we know very little about aging with autism. One aspect that seems to develop differently is the sense of movement, inclusive of sensory kinesthetic-reafference emerging from continuously sensed self-generated motions. These include involuntary micro-motions eluding observation, yet routinely obtainable in fMRI studies to rid images of motor artifacts. Open-access repositories offer thousands of imaging records, covering 5–65 years of age for both neurotypical and autistic individuals to ascertain the trajectories of involuntary motions. Here we introduce new computational techniques that automatically stratify different age groups in autism according to probability distance in different representational spaces. Further, we show that autistic cross-sectional population trajectories in probability space fundamentally differ from those of neurotypical controls and that after 40 years of age, there is an inflection point in autism, signaling a monotonically increasing difference away from age-matched normative involuntary motion signatures. Our work offers new age-appropriate stochastic analyses amenable to redefine basic research and provide dynamic diagnoses as the person’s nervous systems age. Typical neurodevelopment is highly dynamic and variable, with transient changes that tend to occur asynchronously across a given age group. Starting at early infancy, some babies may grow very fast and develop mature neuromotor control before others of the same age group. Other babies may in contrast, be stunted in their growth and/or neuromotor control development . These dOpen access data can provide information to address these questions on neurodevelopment, so elusive today to basic science. In autism, we know very little about the structure of the probability distribution landscape spanned by the parameters that we can derive from the nervous systems’ self-generated biorhythms. There is a paucity of work with limited sample size addressing the stochastic shifts and maturation trends across the population that is aging with autism ,3,4. ConThere is an increasing need to stratify these heterogeneous data generated by clinical diagnoses rooted in observation of behavior . Some efIn recent years, the micro-movements spikes (MMS) fluctuations inherently present in and underlying all natural behaviors that clinicians observe and describe using pencil and paper means, have been assessed across a proposed taxonomy of neuromotor control  Figure . This phIn autism, voluntary MMS have provided evidence for a maturational process absent in the autistic phenotype and served as aid to  classify different developmental stages according to levels of motor noise evolution and probability distribution shape well-correlated with measures of IQ ,4. SinceIndeed, this recent body of work points at the use of MMS criteria as a potential tool to track the evolution of some of the biorhythms of the nervous systems as the neurotypical person ages. We could then use the normative data to build a proper notion of stochastic change, in a probabilistic sense. This would enable us to better understand the aging process of the autistic nervous systems in cross-sections of the aging population, beyond developmental periods and define age-dependent biometrics capturing different rates of change in young highly plastic systems vs. in aging systems whereby neurodegenerative processes manifest. A pressing question in any lifelong neurological condition like ASD is, when does the plasticity of a young system phase-transitions into a neurodegenerative process? Forecasting this transition would allow us to provide neuroprotective therapies in the rapidly emerging ASD aging population.In this paper, we present new analytical methods to automatically, in a heuristics-free manner, stratify patterns of variability inherently present in the involuntary head motions of neurotypical controls and of participants with ASD. Their involuntary micro-movements spikes data are reconstructed from brain images, registered as they try to volitionally control their body to prevent it from moving. As they deliberately attempt to dampen movements’ fluctuations upon being instructed to remain still in the fMRI setting, their involuntary motion data reveal the probability landscape of undesirable motor noise across sections of the ASD developing children and the ASD aging population. We explore data drawn at random from over 2144 records of the ABIDE repository and report on fundamental departures of the person aging with autism from the typically aging person.Across all sites of ABIDE, informed consent was obtained from all participants and/or their legal guardians. The following method have been published previously in various papers ,17,18, bhttp://fcon_1000.projects.nitrc.org/indi/abide/abide_I.html) andABIDE I (http://fcon_1000.projects.nitrc.org/indi/abide/abide_II.html).ABIDE II , and Typical Development (TD), using estimation of stochastic signatures of involuntary head micro-movements of individuals with a formal DSM-ASD  diagnosiRanges of age. Each group (ASD and TD) was split in seven different groups according to their age to assess how the stochastic signature of involuntary head micro-movements evolves with aging. The ranges of age used to that end were the following: from 5 to 10 years old, from 11 to 15 years old, from 16 to 20 years old, from 21 to 25 years old, from 26 to 30 years old, from 31 to 40 years old and from 41 to 65 years old.Inclusion/Exclusion CriteriaThis study includes all sites publicly available through ABIDE I and ABIDE II. They were comprised of 1127 TD and 1017 ASD. As we explained above, those groups were divided by age. ABIDE has data deposited from various labs whereby two types of data are available: cleaned up data sets (whereby noisy images have been removed according to some threshold of head motion amplitude) and raw data sets (whereby no images have been removed). In this work we use the raw data sets with no removal, because we are precisely interested in the head motion data. To that end, we aim at examining all frames continuously acquired in each scan session. Further, we note that different scanner sampling rates influence the nature of the noise in the images, which in turn is reflected in the noise derived from the variability of the raw extracted from the images reflecting the patterns of head motions. Our lab previously reported these effects on the linear (mm/s) and angular (rad/s) speed data . Here weFurthermore, given the inconsistent group sizes per age groups extracted from the ABIDE datasets see , we usedx, y, and z) and three rotational , from EPI time-series registration was saved.Head motion patterns were extracted from imaging data during (rs) fMRI experiments. Motion extraction was performed using the Analysis of Functional NeuroImages (AFNI) software packages . Single-We assess the scan-by-scan speed-dependent variations in the linear displacement of the head during resting-state functional magnetic resonance imaging (rs-fMRI) sessions. The analyses specifically refer to the stochastic signatures of micro-movement spikes  was obtained  ,33. ThesrP and θP, each with m possible states x or y, respectively; the EMD computes how much mass needs to be moved how far, to turn one distribution into the other. The Earth Mover’s Distance (EMD) ,35, also2log(n)) vs. a more recent version in O(n) [γ, to distribute the amount of earth from one place x over the domain of y (or vice versa.)The problem of finding the amount of work that it takes to turn one distribution into another has been posed as an optimization problem that can be resolved using linear programming ,37 in O( in O(n) . Brieflyγ is the joint probability distribution such that rP and θP respectively. To obtain the EMD, every value of the matrix Here the constraints  another .We use the EMD to compute pairwise for each age group of each cohort, the cost of turning one probability distribution into the other.The foundation of these methods has been explained elsewhere  and chose the best fit in an MLE sense. Owing to our prior works using the ABIDE sets ,17 we coi,j) connecting two records from participants i and j. Common network connectivity metrics  were used to characterize the neurotypical cohort spanning the 7 age groups with similar number of participants  and to provide the normative states of the network. Then, network states generated from the data of the ASD cohort were compared against the normative states.The MMS derived from the linear and angular speed were used to group the normalized peak amplitudes into a frequency histogram for each participant. Then, the EMD ,35,37 wafindpeaks function in MATLAB was used. i-participant’s EMD value from the i,j matrix entry was mapped  taken across all other participants. Then, the point located on the Gamma moments parameter space is colored using this scale.The distributions of EMD values was also examined B to asceed as in D–E to thThe idea was to uncover self-emerging clusters of EMD values in each age-group. Low values represent distributions that are similar, while high values represent distributions that are far apart in probability space. Possible scenarios are to have within each age group, highly heterogeneous values, or highly homogeneous values. Further, across the full scatter representing all age groups, we may have highly heterogeneous values, or homogeneous values. We set to interrogate this probability landscape about the evolution of the age groups, the heterogeneity/homogeneity of the groups and the nature of the cross-sectional trajectories of the groups.To interrogate about trajectories, we used the mean values of the three first Gamma moments in each cohort and traced a line connecting each representative point of each age group for each cohort. We also did this for the mode of the age-group scatter, representing the most frequent value and for the median (not shown). The coordinates of the mean values along each axis, were set as the representative point of the scatter and tracked over time. The departure of the coordinates of the point representing the ASD age-group from the neurotypical control age group were obtained using the norm of the vector difference and plotted to ascertain the trends of the trajectories and to identify inflection points of the evolving curve representing the point by point distance between the two cohorts. Lastly, the trajectories were plotted in the scatter of points representing the probability landscape to ascertain their locations within the scatters.A measure of the scatter dispersion was built using the Delaunay Triangulation (DT) of each age-group scatter and the area of each of the triangles obtained. The fluctuations in the values of the area were treated as a point process and their MMS obtained as well. The values of the DT-area MMS were used to empirically fit the Gamma distribution (given that this was the best distribution using MLE ) and thei to all other participants and index the maximal value representing the farthest apart a person is from all other members of the age group, to color code the point in the scatter. Doing this through the full cohort, automatically identifies self-emerging clusters of participants, indicating important differences within a group and across age groups. Cross-sectionally, these patterns inform us about the aging trajectories of ASD in relation to the age-matched normative data and in so doing the empirically estimated personalized signatures of involuntary micro-motions automatically stratify ASD by age . Here we use the distribution spanned by the EMD from participant D by age .A bird’s view of this cohort confirms the notion that ASD is highly variable. But there is another feature that this parameter space and coloring reveals. There is a cluster that completely separates from the rest of the scatter (the oldest group of 41–65 years of age). This indicates a fundamental shift in the signatures of involuntary head micro-motions after 40 years of age. Interestingly, after 20 years of age, the spread in the ASD scatter of each age group decreases, and so does the value of the EMD. The latter, indicating that the participants are getting closer in probability space. This trend is maintained right until 31–40 years of age, when the inflection point marks a fundamental departure in the stochastic signatures of involuntary head motion variations. It is right at this point that the EMD increases maximally as the scatter spread contracts. All participants in this 41–65-year-old group become unambiguously different (far apart) in probability space and rather far from all other age-clusters in the Gamma moments parameter space.The breakdown of these scatters by age are shown in To ascertain the shifting differences in the spread of the scatter of points representing the empirically estimated Gamma moments of the MMS derived from the involuntary linear speed of each participant, we obtained the Delaunay triangulation of the scatter. For each unique triangle found by the Delaunay algorithm, we computed the area and studied the patterns of variability of the triangles’ areas across each age group within each cohort.Tracking the cross-sectional trajectory of the estimated mean value of each age-group scatter, as one moves from age group to age group, revealed a very different cross-sectional aging path in neurotypical controls than in ASD participants. This can be appreciated in The Euclidean distance cumulatively traveled in this Gamma parameter space by the ASD groups comprising 5–20 years of age is ½ of that traveled by their age-matched control counterparts. This can also be appreciated in the acceleration and deceleration of the curves in p << 0.001, Comparison of the autistic cohort to the normative data revealed statistically significant differences in the network connectivity metrics derived from the EMD adjacency matrix (see methods). Each entry in this matrix quantified the pairwise distance in probability space between two members of the age group within each cohort. p << 0.001).Each age group within the typical and autistic cohorts had statistically different clustering coefficient values according to the non-parametric Kruskal-Wallis test. Likewise, pairwise comparison between each neurotypical and autistic age-group yielded statistically significant differences according to this non-parametric ANOVA test C  of the matrix entry. This number is computed based on the travel weight of the network edges, which in our case represent the EMD. The length thus denotes how similar (or different) the family of probability distributions are to get from participant i to participant j. Long travelled distances represent paths along edges that are maximally apart in probability space. At the minimum characteristic pathlength occurring for the 5–10-year-old group, the EDM matrix is much higher for ASD, thus suggesting higher heterogeneity than the age-matched controls. The network distance matrices however have low values, so the shortest pairwise paths are comparable for both groups. Owing to the heterogeneity in probability space, for any two participants within the age group and cohort (ASD or control), it is always possible to find shortest travel path hoping along points of low value in EMD .Another network metric, the characteristic pathlength quantifying the average short-distance paths between a node and all other nodes of the network, was also obtained for each age-group in each cohort D. Large p<<0.001, rank sum test.) Here a more homogeneous ASD group gives rise to lower travel pathlength on average than those of the distribution points from age-match controls. The ASD lower heterogeneity of this age group in probability space appears to be forecasting a dramatic change in the involuntary movements of ASD after 40 years of age  with 95% confidence .We found that each age group could be well characterized by a different family of probability distributions, with different scatter dispersion. The methods provide a new way to automatically stratify the autistic cohort using the EMD on the probability distributions generated by the MMS, and to characterize the differences from the neurotypical cohort by representing the data as weighted connected graphs. The network analyses provided several connectivity metrics amenable to automatically separate atypical autistic development from neurotypical development. More importantly, we were able to automatically identify critical differences in the aging trajectories of the autistic cohort that were absent in the neurotypical cohort for the eldest group (41–65 years of age).These results are relevant to autism research in more than one way. They emphasize the importance of not enforcing a priori any statistical assumptions, but rather allowing the variability inherently present in the data to automatically reveal self-emerging patterns. Further, the results show that a “one size fits all” approach is inefficient to cope with the heterogeneity of autism. Each age group in the autistic cohort had a different stochastic signature unique to the group, spanning a family of PDFs. These were distinguishable from other age groups within the ASD cohort. This was also the case for the normative data, which was nonetheless, overall, visibly more homogeneous in nature than the ASD set. At an individual level, each person in each age-group of the normative cohort was unambiguously statistically different from every other person. This was captured by the large values of the EMD, signaling high effort to transform one frequency histogram into any other frequency histogram of the cohort.In stark contrast to the normative trends, the ASD group had non-uniform changes in the first 20 years of life. On the Gamma moments parameter space A a repreBeyond the MMS related work in ASD, the broader literature of motor control problems studying movements and their sensations in ASD has by now grown considerably ,43, inclUnder the current behavioral criteria for diagnosis and treatments of ASD, these neurological issues are treated as comorbid and secondary to the observed behaviors defining the condition. Under such criteria, the adult autistic population, which is rather large today, never received neuroprotective therapies aimed to slow down the progression of neurological issues. Yet, Parkinsonism is more prevalent and has earlier onset in autistic adults than in neurotypicals of comparable age . Other mThe results presented here strongly suggest that the involuntary micro-movements can not only provide a way to characterize the lack of volitional control of the brain over the body . More importantly, the results offer for the first time the means to differentiate aging with autism from typically aging in this cross section of the population. The methods allowed us to automatically stratify the broad spectrum of autism as a lifelong condition. The cross-sectional aging trajectories of these stochastic signatures pinpoint critical points of change in the statistical landscape of development and aging. These may perhaps forecast important milestones signaling physiological changes in the autistic system.Along those lines, a striking feature of the data concerns the separation of the 41–65-year-old cluster from the rest of the scatter. It may be possible that the high penetrance of Fragile X Syndrome in autism accounts for such differentiation, as motor symptoms are common among this part of the population and often result in Parkinsonism after 40 years of age ,60,61. IWe note that among the autistic participants of ABIDE, there are those who have taken psychotropic medications and those who have not. We have previously shown that the involuntary MMS are present in both types of participants, but that as the number of meds increases, so does the noise levels and the randomness of these involuntary motions ,16. ThisAlong those lines, the sensory-motor axes  were onlIt is hard to imagine a point whereby a neurodevelopmental condition may turn into a neurodegenerative disorder of the nervous systems, particularly since autism is primarily conceived as a mental illness, a cognitive/communicative childhood disorder and hardly defined and treated as a neurological condition. Perhaps it may be time to rethink autism as a lifelong condition that requires close attention to the physiological changes that may accelerate the process of neurodegeneration in the early adult or elderly years. This paper opens a new conversation regarding autism motor physiology across the human lifespan.EBT holds the US Patent “Methods and Systems for the Diagnoses and Treatments of Nervous Systems Disorders” combined in the paper as micro-movement spikes, MMS data type and Gamma process.


Capsule endoscopes (CEs) have emerged as an advanced diagnostic technology for gastrointestinal diseases in recent decades. However, with regard to robotic motions, they require active movability and multi-functionalities for extensive, untethered, and precise clinical utilization. Herein, we present a novel wireless biopsy CE employing active five degree-of-freedom locomotion and a biopsy needle punching mechanism for the histological analysis of the intestinal tract. A medical biopsy punch is attached to a screw mechanism, which can be magnetically actuated to extrude and retract the biopsy tool, for tissue extraction. The external magnetic field from an electromagnetic actuation (EMA) system is utilized to actuate the screw mechanism and harvest biopsy tissue; therefore, the proposed system consumes no onboard energy of the CE. This design enables observation of the biopsy process through the capsule’s camera. A prototype with a diameter of 12 mm and length of 30 mm was fabricated with a medical biopsy punch having a diameter of 1.5 mm. Its performance was verified through numerical analysis, as well as in-vitro and ex-vivo experiments on porcine intestine. The CE could be moved to target lesions and obtain sufficient tissue samples for histological examination. The proposed biopsy CE mechanism utilizing punch biopsy and its wireless extraction–retraction technique can advance untethered intestinal endoscopic capsule technology at clinical sites. As an emerging alternative to traditional endoscopy, M2A, the first commercial capsule endoscope (CE) was approved by the U.S. Food and Drug Administration in 2001 ,4, whichHowever, commercialized endoscopic capsules have several limitations, including passive locomotion due to peristalsis motions, the inability to perform targeted diagnosis, the long diagnosis time, and the single visualization modality only . To overSeveral advanced functions are needed for CEs, e.g., biopsy, drug delivery, and tattooing ,13,14,15Herein, we propose a novel biopsy methodology utilizing a clinically available biopsy needle that can be integrated into a conventional CE. A battery-free screw mechanism is developed to actuate the biopsy punch using the external magnetic field. The punch needle is stowed inside the capsule body during locomotion to avoid undesired tissue extraction and prevent perforation. It is actively extruded to obtain biopsy samples owing to the screw mechanism that converts the rotation motion of a permanent magnet into linear motion under the rotation magnetic field. After tissue is extracted, the punch needle is retracted into the CE body, and the investigation process is continued. A distinct advantage of our design is that the biopsy procedure can be viewed through the CE’s camera. The new design of the biopsy CE enables independent magnetic actuation for both flexible locomotion and tissue acquisition. This provides a complete diagnosis procedure for the intestines, including the moving, scanning, and sampling of tissue.The remainder of this paper is organized as follows: The developed biopsy CE system has two main functions: visual inspection for intestinal organ diagnosis and tissue extraction for further histological analysis. 3 are suitable for a standard-sized CE [3) for reliable histological analysis [The requirements for the practical biopsy endoscopic capsule considered in this study are presented in sized CE . The wirsized CE . For extsized CE ,27. Furtsized CE . The biosized CE , and colanalysis ,29. FinaTwo common biopsy tools are used clinically: biopsy forceps and biopsy punch needles. In this study, we used the latter for the CE because it is superior to the biopsy forceps. The biopsy needle has played an important role as a medical diagnostic tool. It is inexpensive, simple, highly efficient, and easy to use. The biopsy needle was first used to perform skin biopsies and was then gradually used in intestinal biopsies employing endoscopic instruments to collect samples from neoplasms and intestinal-wall abnormalities ,30. The The biopsy module is designed by incorporating a screw mechanism that can extrude and retract the punch needle magnetically. By applying a rotational magnetic field, the extracting or retracting motion of the biopsy tool can be controlled without consuming internal battery power. The conventional endoscopic capsule is a passive device; thus, its motions are limited to the peristaltic movement of digestive organs. This leads to ineffective diagnosis and therapeutic motion in small tubular organs and unreliability in large digestive organs such as the stomach and colon. Therefore, the motions of the CE must be actively controlled. In this study, we utilized an EMA system to fulfill the requirement of controllable wireless active locomotion for the endoscopic capsule . This EMM assigned to the x-axis, and Zr, the capsule is driven by a magnetic torque, as follows:M = (X MY MZM)T, B = (X BY BZB)T, and (i j k)T is the unit vector of the world coordinate system. Because the magnetic field is proportional to the input current of the electromagnetic coil, the controlled magnetic field B can be calculated via a linear combination of 10 coils, as follows:mth coil and the input current, respectively. b (3 × 10 matrix) is the mapping matrix of the magnetic field of 10 coils with respect to the input current vector I (10 × 1 matrix). The induced magnetic field aligns the vector M along the vector B.When the capsule is within the ROI of the EMA system where the magnetic field is controllable, the resulting magnetic torque and force acting on the permanent magnet steer the capsule and push it along the planned path, respectively. The magnetic force pushing the capsule can be calculated using the following equation:F is identical to that of B, although the magnitudes differ.Normally, the capsule is pushed along the alignment direction; therefore, the direction of the vector p  generates a cutting force Fr to tear off the tissue, as shown in The tissue-harvesting process consists of two steps. In the first step, the capsule is pushed against the intestinal wall by a magnetic force Fp see a, and thx-axis of the capsule coordinate system or the axial axis of the capsule. The rotation of the magnetic field vector B with respect to an arbitrary axis u by an angle φ can be expressed as:The punch tool is extruded by screw motion before sampling. The screw motion is created by rotating PM#2 under the rotation magnetic field about the M is collinear to the x-axis; thus, the vector u can be taken as M that is the current posture of the CE. The resultant magnetic torque is exerted on both permanent magnets. Therefore, the amplitude of the rotation magnetic field should be small enough to reduce the vibration of the capsule body but large enough to actuate PM#2.In Equation (5), the magnetization vector s represents the sharpness, and punchd represents the diameter of the tip of the biopsy punch. In this study, we used a punch tool with outer and inner diameters of 1.5 and 1.2 mm, respectively, and the sharpness of the tool tip was 0.03 mm. Therefore, the required cutting force punchd = 1.5 mm).Once the punch needle is fully exposed, the operator can observe the target position and the needle through the camera of the capsule. The capsule is steered to direct the biopsy tool toward the target. Then, the magnetic force in Equation (4) is generated for the tool to penetrate the tissue, creating a cut imprint on the mucosal layer. The shear stress induced by the biopsy tool must be larger than the standard destructive stress of the mucosa layer, which is given as  1.2 MPa . Therefod = 25 mm is the distance from the center of PM#1 to the tip of the fully extruded punch tool. Accordingly, the capsule must be able to create a minimum of 0.0042 N∙m of physical torque.Finally, the rotation motion of the capsule body is used to tear off the target. The required magnetic torque can be estimated as follows:M = 955,000 A/m. In this simulation, we used a gradient magnetic field of 0.5 T/m and a magnetic field of 0.03 T for the propulsion force and torque, respectively. The inner diameter of PM#1 was fixed to 5 mm to leave space for the camera and its signal wire. We simulated the magnetic response with various values of the outer diameter and height. We selected a magnet with an outer diameter of 11 mm and a height of 6 mm, which is denoted as PM#1 in The propulsion force and rotational torque of the capsule body were estimated for various volumes of the permanent magnet to optimize the dimensions of the permanent magnet PM#1. The designed ACE with the biopsy punch mechanism was fabricated and assembled for experimental evaluation, as shown in The experimental setup is illustrated in A set of in-vitro tests was performed to evaluate the efficiency of the control of the magnetic field for biopsy needle actuation and capsule locomotion. Because the screw-shaped body and screw guide were printed by the 3D printer and the friction coefficient was difficult to measure, we experimentally determined the appropriate amplitude of the rotation magnetic field to extrude the needle. It should be sufficient to actuate the screw mechanism and small enough to prevent the vibration of the capsule body. By adjusting the magnetic-field amplitude with step inputs of 0.2 mT, a range of 4–6 mT  was used to activate the biopsy needle.Y-axis in this test) using a magnetic field of 15 mT and then extruded the punch biopsy using the rotation magnetic field with an amplitude of 4 mT. After 3 s, the ACE prototype could extrude the biopsy punch from its body without affecting the posture of the capsule. However, the position of capsule was changed slightly, owing to the tubular shape of the capsule body, which caused undesired rolling motions. Subsequently, the capsule was moved to arbitrary positions along the Y-axis and X-axis; the rotation magnetic field was disabled in this phase to avoid unwanted motion of the needle. The biopsy punch was stable during the locomotion. Finally, the rotation magnetic field was applied in the reverse direction to retract the biopsy tool into the body of the capsule. By controlling the external magnetic field, we could actuate the needle and move the capsule independently. It took approximately 3 s to extrude and retract the needle.First, the ACE was placed in an acrylic phantom in the ROI of the EMA system. Experiments were performed in air, and the capsule was manipulated manually by the user. Second, a test was performed to evaluate the targeting accuracy of the biopsy tool under the open-loop control system. We conducted targeting experiments using a phantom model with a known geometry and targeting markers. The phantom had a cylindrical shape with a millimeter grid. Four double-rounded targets were marked inside the phantom: 1-mm-radius red inner targets and 2.5-mm-radius blue outer targets. The ACE with the pre-extruded needle was placed in the phantom and controlled to approach all the red targets. The capsule was first aligned in the desired direction by the magnetic field and was then pushed forward/backward by the magnetic force. The user could manually increase or decrease the magnetic force to obtain large or small movement steps of the capsule, respectively. As shown in To verify the cutting force of the proposed needle punching biopsy analyzed in Additionally, in a comparative study, we measured the cutting forces of the biopsy punch and the biopsy forceps commonly used at clinical sites by endoscopy clinicians, to show that it is more beneficial to integrate punch needle into CE for tissue extraction. We measured the cutting force of the clinically used endoscopic biopsy forceps  and the biopsy punch, as shown in The performance of the developed biopsy CE was evaluated through ex-vivo experiments. We used a piece of porcine small intestine  and fixed it in a semi-cylindrical tube. The small intestine and the biopsy ACE device were placed at the center of the ROI of the EMA system. First, the ACE was controlled to move to the target point. An external electromagnetic field was generated to align the ACE in the desired direction, and then a gradient field was used to push it in the desired direction. The rotation magnetic field was disabled during the locomotion process to prevent undesired motion of the biopsy needle. Once the ACE reached the destination, the gradient field was turned off, and the rotational magnetic field was generated to extrude the needle. As mentioned previously, one of the advantages of the proposed biopsy CE over other tools is that the extrusion step and the entire sampling procedure can be viewed using the camera of the capsule. The proposed biopsy CE could be controlled to move to target positions, and the developed biopsy mechanism was successful in sampling biopsy tissue. There was no perforation on the intestine. To validate the quality of the extracted samples, we conducted an examination, as shown in For the investigation of the harvested biopsy tissues, hematoxylin and eosin (H&E) staining was performed . After tIn this study, as a critical application for clinicians, a biopsy modality based on an actively controlled CE using biopsy needle punching was developed. This was the first trial to transfer a clinical biopsy tool into a miniaturized CE, which allows the collection of biopsy tissue in deep regions of the small intestine. The developed biopsy CE has several advantages. The biopsy process is manipulated magnetically by an external control system; therefore, it does not consume the energy from the internal battery of the capsule, which has limited power. The new design allows the operators to view the entire biopsy procedure, including the needle actuation and biopsy punching motions. This feature is a significant advantage of our design, as it can enhance the retrieval rate of biopsy tissue. Therefore, the proposed tool has the potential to expedite the detection of abnormal tissues and improve the diagnosis accuracy.The proposed biopsy module is simple and easy to operate. By utilizing a small magnet covered by a screw-shaped body, the biopsy module can be actuated independently from the locomotion. The number of components of the biopsy module is small, making it small and inexpensive to fabricate. Additionally, the screw mechanism can be used for other endoscopic capsule applications in which the tools must be kept inside the capsule body during locomotion for safety and exposed at desired location .Although the proposed mechanism can facilitate endoscopy and biopsy procedures, it has limitations for application at clinical sites. Performing multiple biopsies in different target regions is impossible because of the space limitation. However, the proposed mechanism can be used to biopsy multiple tissues at the same target or along a segment of the intestine under suspicious or abnormal conditions for special cases, such as aged patients who may have difficulties with conventional endoscopy due to the discomfort and side effects. The proposed capsule can function easily in tubular organs . It might be difficult to operate in the stomach owing to the folding structures and high-curvature parts . In this study, we did not quantify or model the effect of the intestinal environment for the precise control of the capsule motion and posture inside the intestine. Additionally, the motions of the living body and the pressure of internal organs were not considered in the ex-vivo tests.In the future, the developed biopsy capsule will be tested in animals, followed by clinical trials. The working environments, which affect the control performance, will be analyzed for in-vivo tests. The in-vivo experiments will be conducted on subjects to validate the proposed system with the scaled up system. A feedback system and advanced control techniques will be integrated with the EMA system to track the capsule and improve the control performance of the system in the living body, where there are noise and uncertain factors  ,35. AdvaIn this paper we have presented a novel retractable needle punching biopsy methodology integrated with an ACE that could perform robotic movement for the histological analysis of intestinal diseases. Numerical analysis and in-vitro tests proved the feasibility of utilizing an available medical biopsy punch for the ACE to sample tissues in the intestine. The developed screw mechanism was actuated magnetically to extrude and retract the biopsy tool without affecting the posture of the capsule. In ex-vivo tests, we successfully demonstrated a full intestinal diagnosis procedure, including locomotion for visual inspection, needle actuation, and tissue acquisition.Regarding clinical applications, the proposed biopsy CE with the noninvasive monitoring ability and microscale-functionality could operate in the intestinal tract and provide a view of organs for drug delivery or tissue sampling. The two main contributions of this work are summarized as follows: (1) we demonstrated a novel battery-free screw mechanism for an ACE driven by an external EMA system, and (2) we performed the first trial integrating a medical biopsy punch with an ACE to obtain intestinal samples. In conclusion, we demonstrated the potential applicability of the biopsy punch with the developed screw mechanism to the recently developed five-DOF locomotive active capsule for gastrointestinal-tract diagnosis.


The use of fiberglass in dentistry has increased due to the improvements in the development of adhesive techniques reducing the cost of treatment and avoiding abutment tooth craving. The present study aims to evaluate the clinical usefulness of the new technique to fabricate a direct fiber-reinforced composite bridge (FRCB) over a long period of time. Twenty-one FRCB were performed with the new direct technique on 21 patients with a mean age of 58.85 years and female predominance in the Faculty of Dentistry of Oviedo (Spain). The framework design releases the embrasures allowing adequate interproximal brushing, avoidance of periodontal disease and interproximal caries. A baseline examination was performed and the patients were examined regularly at six-month intervals (nine years’ follow-up). The restorations were also evaluated by an examiner using parameters to check their stability, longevity and the lack of periodontal disease. The most frequent location was the maxillary premolar region and the purpose of the restorations was to give a definitive bridge in 100% of the patients. Only one total debonding of the prostheses was detected during the observation period at 24 months and three partial adhesive–cohesive veneering composite fractures at the pontic after 60, 72 and 84 months, respectively. Kaplan–Meier was performed to detect the overall survival rate of the restorations at the end of the follow-up. Nine-year survival rates for the FRCB was 95.2%. All the cases had a clinically acceptable periodontal condition and an interproximal absence of caries in the abutment teeth. Currently, this type of restoration allows a minimally invasive aesthetic and is an affordable procedure, being a good alternative to other types of treatments. Currently, prosthetic replacements of anterior or posterior edentulous segments present an aesthetic challenge to clinicians. A variety of therapeutic modalities, from implants to conventional fixed partial dentures or even removable partial dentures, have been used for the replacement of missing teeth. Each of these techniques has advantages and disadvantages related to their durability: the overall complexity of the cases, their cost  and challenges to oral hygiene after the treatment ,2.Fiber-reinforced technology was initially used as a splint material for periodontally involved teeth and to stabilize avulsed teeth . NowadayRegarding the type of fiber-reinforced, glass fiber or the ultra-high molecular weight polyethylene (UHMWPE) fiber is normally used. These materials have shown better performance as the core of FRCBs ,5. In reFiber-reinforced types are heterogeneous and anisotropic, meaning their properties strongly depend on the direction in which they are tested relative to their fiber orientation. For unidirectional fiber-reinforced types in which the fibers run parallel and in one direction, properties are highest in the direction parallel to the fibers and lowest in the direction perpendicular to the fibers. To give the fiber better properties, they create meshes with multiple fiber orientations several times. This can be achieved in one of two ways: either by placing unidirectional fibers in multiple directions or by using a braided or woven fabric .At this moment, FRCB is performed with two different types of techniques (direct or indirect techniques). The direct technique allows the prosthesis to be done in a single appointment, excluding laboratory needs and reducing the cost of treatment. Even so, it is necessary that the technician has great knowledge of fiber management and preparation of the operative area (isolation with the rubber dam) ,15. On tIf we take all these considerations into account, this material offers an attractive alternative for the treatment for the replacement of tooth loss. On the one hand, this type of prosthesis allows easy repairs in a single appointment such as composite chipping, without the help of a laboratory technician. Other advantages include reduced cost  compared with conventional bridges, absence of metal allergies and a natural feeling ,17.The aim of this clinical retrospective study was to analyze the survival rate and rule out the possible complications that this new direct technique for performing FRCB can present. We believe that this proposed aim will allow us to discard the null hypothesis that the nine-year survival rate of follow-up of the FRCB performed with this new technique has been deemed unacceptable.Between June to July 2010, 21 patients with a complaint of an anterior or posterior single missing tooth were randomly treated with an FRCB in the Faculty of Dentistry of Oviedo, University of Oviedo, Spain. The main reason for the treatment with FRCB was the need for a low-priced fixed prosthesis and the need to save tooth substance. We obtain signed informed consent from patient of the pictures in this paper.Maintenance of good oral hygiene;No parafunctional habits;The absence of large restorations or caries lesions on the abutment teeth;No periodontal disease of the abutment teeth  the wax-up and the silicone keys for the tooth replacement . Figure 2. The proximal faces of the adjacent teeth delimiting the edentulous space were carved up to the level of the ideal point of contact (inlay cavities), to position the future horizontal structure of the fiberglass bridge .® Post GT, VOCO GmbH, Cuxhaven, Germany) bonding to the adjacent teeth. Firstly, when the isolation of the operative field with the rubber dam was made, the fiberglass pin was adjusted to size and silanization according to the instructions by the manufacturer. Later, the inlay cavities were etched with Ultra-etch®  for 20 s, rinsed for 10 s and dried for 10 s. The etched surfaces were covered with a layer of a universal adhesive resin , thinned using a brush, and cured for 20 s with a light- polymerizing unit. A flowable resin  was used to cover the inlay cavities (inlays retainers) and the fiberglass pin to shape the transverse structure of the future bridge  and nanohybrid composite resin . The most frequent area was the maxillary premolar region followed by the maxillary incisor sector and the purpose of the restorations were as a definitive bridge in 100% of the patients .Two patients did not complete the observation period (exitus at 54 and 72 months).Only one total debonding of the prostheses was detected during the observation period at 24 months. This prosthesis was later replaced with a conventional full-coverage fixed prosthesis.Three partial adhesive–cohesive veneering composite fracture at the pontic. They occurred either in the occluso-buccal or occluso-lingual area of the pontic after 60, 72 and 84 months, respectively, and one FRCB needed polished at 72 months. They were repaired and polished in situ .All the cases had a clinically acceptable periodontal condition due to the embrasures and were released allowing adequate interproximal brushing. The patients reported no caries, no temperature or pressure sensitivity during the follow-up and all the abutment teeth were vital at the final examination appointments.As shown in the Kaplan–Meier curves, the overall survival probability at 108 months for the FRCB was 0.952 , as well as an endless combination of these with restorative materials to make the pontic, even natural teeth. On the other hand, FRCBS are used with a very broad age spectrum. This is because at very early ages they are used as temporary prostheses after orthodontic treatment or after a non-restorable dental trauma ,22 untilNowadays, the incisive localization is indicated as the most frequent region for this type of restoration ,10,23. AThe length of the edentulous space is another consideration to keep in mind. Large edentulous spaces (more than one tooth) would be a contraindication for this type of prosthesis, since it would increase the probability of fracture or failure of the FRCB. For this reason, it is important to consider a patient with small edentulous spaces and very soft contact points on the FRCB pontic.Failure by partial or total debonding of the FRCB and framework fracture, as witnessed under clinical condition, is a well-known phenomenon in dental literature . VariousIn relation to the fiberglass pin, this should have a higher fracture resistance than the average masticatory forces and should contain physical properties such as an elastic modulus, compressive strength, and coefficient thermal expansion similar to the tissue (dentin) that we seek to replace as the core of the FRCB ,29. For Recently, Goguta et al.  publisheRegarding the periodontal aspect and the development of interproximal caries, few articles have been written on this very important aspect . We consAnother problem that practitioners found in this type of rehabilitation was its durability. Normally they were designed to be used provisionally, as the adhesion techniques were underdeveloped due to the fragility of the fiberglass. At present, they are used for definitive restorations, because these problems practically do not exist and the survival has extended exceeding up to even six years . In our On the other hand, we recognize the limitations of our study in relation to the sample size and the lack of a control group. Therefore, the results can only be considered preliminary. It would be interesting to increase the number of patients in the future, as well as the number of dental schools to collaborate with in order to see if our results can be extrapolated to a large sample with a control group.In conclusion, on the one hand, the results obtained discard the null hypothesis as the nine-year survival of the FRCB is acceptable .The periodontal inflammation aspect on the pontic area: the framework design releases the embrasures allowing adequate interproximal brushing, avoiding periodontal disease and interproximal caries.Long term survival: this proposed protocol which uses inlay retainers and a core with two “T” shaped pins reinforces and stabilizes the FRCB, allowing greater survival over time.On the other hand, this technique could solve two main drawbacks with this type of restoration:


In this paper, we investigate the progression of Ascending Thoracic Aortic Aneurysms (ATAA) using a computational model of Growth and Remodeling (G&R) taking into account the composite  and multi-layered (media and adventitia) nature of the aorta. The G&R model, which is based on the homogenized Constrained Mixture theory, is implemented as a UMAT in the Abaqus finite-element package. Each component of the mixture is assigned a strain energy density function: nearly-incompressible neo-Hookean for elastin and Fung-type for collagen and SMCs. Active SMCs tension is additionally considered, through a length-tension relationship having a classic inverted parabola shape, in order to investigate its effects on the progression of ATAA in a patient-specific model. A sensitivity analysis is performed to evaluate the potential impact of variations in the parameters of the length-tension relationships. These variations reflect in variations of SMCs normal tone during ATAA progression, with active stress contributions ranging between 30% (best case scenario) and 0% (worst case scenario) of the total wall circumferential stress. Low SMCs active stress in the worst case scenarios, in fact, affect the rates of collagen deposition by which the elastin loss is gradually compensated by collagen deposition in the simulated ATAA progression, resulting eventually in larger aneurysm diameters. The types of length-tension relationships leading to a drop of SMCs active stress in our simulations reveal a critical condition which could also result in SMCs apoptosis. Nowadays, the paramount importance of mechanobiology is widely acknowledged in morphogenesis and pathogenesis  was developed by Humphrey and Rajagopal  and, theDespite the significant insight of the CMM methodology in arterial G&R, it has generally been employed in the case of canonical problems  and, then, regularizing the blood pressure  moving from its initial undeformed configuration, say before any G&R happens, occupying a volume Ω0, of boundary ∂Ω0, to a time dependent deformed configuration occupying a volume Ω(t), of boundary ∂Ω(t) at time t. The motion of the continuum is defined through a deformation mapping, such as x = ϕ by which a solid particle at the reference state is transformed to the spatial configuration. The total deformation gradient F of a mixture, consisting of different constituents , can be expressed asWe consider the three dimensional deformation of a continuum . Additionally, the volume map J is defined asThe deformation gradient essentially relates a fiber at material configuration to its spatial counterpart .linking a reference volume element into the deformed states (F and (2) the deformation gradient of each constituent i of the mixture  is decomposed into an elastic Two main assumptions are made for the deformation gradient on the basis of CMT, namely, (1) all constituents deform together resulting in a unified deformation gradient where the elastic deformation gradient F(t0) = I where I is the identity tensor, each constituent i of the mixture has an individual elastic deformation gradient Initially i in the fiber direction whose unit vector is denoted by where The G&R deformation process is typically governed by the balance of the linear momentum equationP denotes the first Piola-Kirchhoff stress tensor, b0 is the body forces per unit mass and in which DIV is the material divergence operator, W (per unit undeformed volume) is introduced  represent, respectively, the mass densities and strain energy densities (per unit mass) of each individual constituent.In the above equation, A nearly incompressible Neo-Hookean material model is introduced for elastin as  of the elastin, respectively. where μwhere The strain energy density of collagen families is described with a Fung-type exponential expression  and where actmax denotes the maximal active Cauchy stress and λmax and λ0 are parameters denoting the active stretches at maximum and zero active stresses, respectively.Moreover, σIt is worthwhile noting that the same strain energy density functions are assumed all across the aorta. However, different material properties and mass densities of the individual constituents are assigned to each layer (media and adventitia). Note that the intima layer is disregarded in this work, due to its relatively thin thickness.Having Equation (6), it is now possible to evaluate the second Piola-Kirchhoff stress tensor using the following relationsSi is the Piola-Kirchhoff stress of constituent i and φi its volume fraction in the current configuration, which may be written, such aswhere The obtained second Piola-Kirchhoff stress can simply be pushed forward in order to compute the Cauchy stress tensorTherefore, the Cauchy stress for each individual constituent can be expressed aswhere act was replaced by act = 1 meaning that In Equation (15c), λu et al.  who assuIn this work, a two-layer arterial model was considered where the rate of mass degradation or deposition of collagen in both layers was computed, such asm and where Dmax is the maximum damage length, X is the material position, Ldam and tdam are the spatial and the temporal damage spread parameters, respectively, and Te is the average turnover time for elastin constituent.whose objective is to describe additional mass deposition or mass degradation  in elastin. i at time t can be evaluated by solving the following system of equations  structural mesh, made of hexahedral elements, is reconstructed across the arterial wall using the Abaqus finite-element package   while free (no-traction) boundary condition are assigned in the radial direction (r).The geometry is subjected to a luminal pressure of 80 mmHg (diastole), an axial deposition stretch of nd Avril . The appGuzzardi et al.  found thA parametric study was carried out about the effects of three parameters on G&R progression:tdam),the time at which the artery is maximally damaged (the rate of collagen deposition (max).the maximum contractility of SMCs ; and (2) the ratio between the SMCs active stress and the total stress field (Rt).In order to quantify the contribution of SMCs active tone in the stress distribution field, two ratios were considered, namely (1) the ratio of the SMCs active stress with respect to the SMCs (active and passive) stresses . The curves are comparatively depicted in max) has led to a larger decrease in active stress in comparison to the previous case, once reaching the maximum active stress value.Interestingly, the active stress even drops and reaches zero see . In thismax) and plotted for various damage times tdam. As clearly shown in max and The distribution of the normalized collagen density  is depicted in tdam = 40. The stretch evolution shows that the ATAA dilation evolves in the opposite direction of the rate of collagen deposition. This occurs as more collagen is deposited for compensating elastin degradation: the thicker the artery and the smaller the displacement. This can be related to the evolution of the active stresses in which the inverted parabola behavior is more evident for the bigger value of tdam. In this case, increasing the damage time increased the developed stretch due to G&R in the artery.The evolutions shown in tdam = 40. The results are compared for different values of the maximum SMCs stretches shown in media and adventitia layers. In fact, the longer G&R occurs, the more stress is transferred from the media to the adventitia layer.The absolute value of the principal stress distributions are shown in max where various rates of collagen deposition are investigated. As expected, faster collagen deposition results in less dilation of the aortic wall and, therefore, faster convergence of the numerical solution. This trend can be observed for both diameter and thickness whose opposite trend is inevitable. In addition, the effects of SMCs maximum contractility, especially in the case of diameter, is evident as a smaller λmax has led to an increase in the diameter. However, this increasing trend of diameter does not completely agree with the thickness of the artery. It seems that thickness decreased in the critical condition (λmax = 1.0).The same behavior can be observed in tdam = 40 in the media layer for different values of maximum SMCs contractility.The contour plot of the arterial wall thickness and displacement distributions are shown in In this paper, growth and remodeling of a patient-specific aortic geometry has been computationally modeled using the homogenized CMT in order to predict ATAA evolution while the artery has undergone proteolysis of elastin localized in regions of deranged hemodynamics. To the best of the authors' knowledge, it is the first time that the effects of possible variations in SMC contractility on ATAA progression are simulated in a multi-layer patient-specific model. The results reveal a possible critical condition in which the active stress of SMCs can reduce to zero, which can be interpreted as if SMCs do not pull onto the extracellular matrix anymore, potentially leading to apoptosis.The paramount importance of the SMCs role in short- and long-term changes of arterial responses is reported in Cox , 1978, HCompared to the well-known model proposed by Zulliger et al. , our modZulliger et al.  have a mZulliger et al.  considerfor the length tension relationship, Zulliger et al.  used a Hin vivo measurements of the active stress in vivo.It is worth noting that it is the first time that variations of the active stress are investigated in G&R progression through computational modeling. The situations that we have considered for these variations of the active stress remain partly fictitious because there are no tdam), the rate of collagen deposition (max) in order to study the effects of active SMCs on G&R of a patient-specific ATAA geometry. Results illustrate the importance of damage time on the expansion rate of the artery such that the larger value of tdam leads the higher rate of G&R. Note that elastin degradation during ATAA growth may be related to multiple biological and mechanical parameters including abnormal distribution of Wall Shear Stress (WSS)  of a patient-specific geometry should be consistent with ex vivo bulge inflation data of an ATAA segment excised after the surgical intervention of the same patient. However, the in vivo material properties of ATAAs (Farzaneh et al., In this work, the constitutive parameters for the patient-specific model were estimated by curve fitting from the in vivo in order to improve the predictions of G&R computational models.We have generated fictitious situations where the active stretch of SMCs evolves with the actual stretch of the tissue and have echoed this evolution onto the active stress through the inverted parabola function. Although these situations can be justified if SMC proliferate at an extremely low rate and do not adapt to aneurysm progression, they remain fictitious and there is a pressing need to characterize the evolution of SMCs length-tension relationships in aortic aneurysms Several biological pathways may be activated during aneurysm development and induce adaptation mechanisms of SMCs that were not considered in this work. More specifically, the distribution of WSS is complex in ATAAs (Condemi et al., In this work, the contribution of SMCs contractility during aneurysmal growth and remodeling has been computationally investigated with a multi-layer patient-specific model of the human aorta subjected to localized elastin degradation. The model relies on the homogenized constrained mixture theory. The results show that the active contribution of SMCs is of paramount importance in analyzing the total stress field of the mixture. It, in fact, affects the rates of collagen deposition by which the elastin loss is gradually compensated. Interestingly, a critical condition has been observed, under which the active stress of SMCs could drop and possibly result in apoptotic conditions. Future work will carry on investigating the major role of SMCs contractility on G&R in aneurysm development, considering supplemental biological pathways in our computational model in order to account for actual adaptation mechanisms undergone by SMCs.The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author/s.The studies involving human participants were reviewed and approved by CHU Saint-Etienne. The patients/participants provided their written informed consent to participate in this study.AG: software implementation, simulations, validation, analysis of results, and writing—original draft presentation. All authors supervision of the research, methodology, funding, analysis of results, reviewing, and editing of manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


As living standards improve, people’s demand for appreciation and learning of art is growing gradually. Unlike the traditional learning model, art teaching requires a specific understanding of learners’ psychology and controlling what they have learned so that they can create new ideas. This article combines the current deep learning technology with heart rate to complete the action recognition of art dance teaching. The video data processing and recognition are conducted through the Openpose network and graph convolution network. The heart rate data recognition is completed through the Long Short-Term Memory (LSTM) network. The optimal recognition model is established through the data fusion of the two decision levels through the adaptive weight analysis method. The experimental results show that the accuracy of the classification fusion model is better than that of the single-mode recognition method, which is improved from 85.0% to 97.5%. The proposed method can evaluate the heart rate while ensuring high accuracy recognition. The proposed research can help analyze dance teaching and provide a new idea for future combined research on teaching interaction. With the development of artificial intelligence technology, the continuous change of traditional teaching methods, and the popularization of online and mixed teaching, art teaching has also undergone significant changes. It is becoming more and more common to give lectures in person and video lectures. With the development of deep learning and machine learning , teachinArt is an emotion . WhetherOnline and mixed teaching courses are usually recorded through video images. Therefore, given the existing equipment and teaching environment, there is an urgent need for a new teaching evaluation method to understand the student’s learning situation and consider their psychological conditions. In video teaching evaluation, video stream information includes spatial and temporal dimension features. Therefore, obtaining effective spatiotemporal dimension features becomes the focus of video field research. Given the achievements of convolutional neural networks in the image field, how to introduce a convolutional neural network into the video field has become the focus of many researchers. A 3D convolutional neural network is a video action recognition algorithm emerging in recent years, including the 3D convolutional network (C3D), the pseudo 3D reactive network (P3D) and the influenced 3D convolutional network (I3D) . CompareOn this basis, people complete the work of extracting human motion features and motion posture information from video streams. In the analysis of the mental state, people usually use EEG and ECG technology to complete cognitive state assessment and emotional calculation. However, such equipment is expensive and cumbersome for dance art teaching. It is acceptable to conduct small-scale research, but applying it to large-scale education is difficult. Some emotions, such as tension and relaxation in work, study and life, can be expressed through heart rate . With thTherefore, to meet the needs of teaching actions evaluation and psychological state analysis in dance art teaching. This article takes art dance teaching as the research object and uses existing video technology and wearable devices to evaluate dance teaching methods. In the actual teaching, due to the occlusion of images or personal privacy, the video cannot completely show the students’ movement status, so the wearable device heart rate data is used to complement each other to complete the high-precision recognition of students’ dance movements while completing the evaluation of psychological emotions to a certain extent. In the method proposed in this article, dance video data is used to extract motion features, the TCN network is established, and state judgment is formed. At the same time, the dancer’s state is recognized according to the collected heart rate data. Finally, it is fused with image recognition data to form an adaptive decision-making model, complete dance action recognition, and help teachers complete the analysis of the psychological state.In practical application scenarios, the single-mode data recognition method has a high rate of false recognition due to the influence of occlusion or signal loss. To meet the needs of students’ action in art teaching, this article combines computer vision technology and ECG heart rate recognition to jointly evaluate the students’ psychological characteristics and activities. The overall process is shown in First, we should preprocess their original video images to ensure students’ privacy in art teaching. According to the need for action evaluation and action observation in art teaching, this article selects the Openpose framework to take the lead in extracting skeleton frames . The OpeSt is the joint point confidence map output at t, and Lt is the affinity of the two pairs of relationship nodes output at t, namely, the weight coefficient. To ensure network convergence, the method uses the L2 loss function for the loss functions of both branches. To avoid gradient disappearance, only the output of the last layer is used in the prediction process. The loss values at each stage are shown in t represents the predicted value at different stages, p represents each pixel point, W (p) represents the missing mark at this point, and its value is 0 or 1. If it is 0, the loss value is calculated, as shown in the overall loss value After the human skeleton extraction based on Openpose, the 3D map convolution technology is used to complete the network construction of motion features. The 3D convolutional neural network is a deep learning algorithm widely used in video action recognition. Compared with the convolutional neural network algorithm in the image field, its essential difference is that the two-dimensional convolution core in the image field is “expanded” into a three-dimensional convolution core. Its schematic diagram is shown in The convolution process of graph map convolution adopted in this article is shown in vti, vti is the frame of node i in the skeleton node sequence at time t, which represents the adjacent set of node vti with K subsets, Z is the node feature of vti, and lti represents the corresponding mapping of B to K-1 data, namely convolution. The network structure layer is shown in etc. On this basis, the sliding variance of the sliding window is used as the feature, and its calculation method is shown in As for the heart rate signal collected by wearable devices, its accuracy is limited. The frequency domain features such as FFT, wavelet transform and Hilbert Huang transform can hardly produce the expected observation effect due to the noise problem . Therefocj is the heart rate value collected at the j point, w is the width of the sliding window, j point window. In this way, the size of the sliding window w can be changed to adapt to the size and length of the action, thus ensuring the algorithm’s accuracy to a certain extent.After feature extraction is completed, the pattern shown in To ensure the optimization of model identification, this article adopts an adaptive multimodal decision fusion method . The claWi of both. At this time, the result generated by the iteration is optimal.The calculation is carried out according to the label vector Jj in the training process. The goal is to maximize the probability in Wi becomes the optimal weight matrix, similar to the voting mechanism. The two types of optimal results are fused through the optimal weight to achieve optimal identification under data fusion.In this article, according to the characteristics of dance teaching in art teaching, four main dance movements in school teaching are selected for recognition, and video recording equipment is set up in the particular classroom. This article uses an RGB network camera to collect video data, and heart rate is monitored through the bracelet. As shown in At the same time, to reference the analysis of typical signals in teachers’ teaching, this article analyzes the specific signals of tension, as shown in After the model is built, the network model shown in To verify the effect of the adaptive fusion method proposed in this article, in addition to mutual recognition, we also use video and heart rate data to recognize dance movements and compare some leading indicators in machine learning. The recognition indicators used in this article are the precision P, recall R, and F1 score . The mulThe confusion matrix formed by the model prediction results is shown in To more intuitively illustrate the classification effect among the three models, this article calculates the accuracy rate, property right rate and F1 score of the three models, respectively. By comparing the index shown in Recently, it has been essential to upgrade teaching methods, teaching contents and teaching evaluation methods in an all-around way through new technologies. In art teaching, for example, vocal music teaching uses natural language processing technology to complete speech recognition, and dance teaching uses video image analysis technology to identify dance movements to form a refined evaluation. Video image technology has developed rapidly, and the number of contributions to top-level computer conferences such as CVPR and ICCV has increased year by year, becoming the most important research hotspot in the computer field. Based on this, this article categorizes and recognizes common actions in art dance teaching through video stream data. At the same time as technological development, more attention should be paid to students’ mental health. Especially in the current new pandemic, everyone’s activity area and social experience are limited, which should pay more attention to psychological counseling in teaching.In teaching, especially in art teaching, we should combine the law of students’ psychological growth, master the art of teaching methods and methods skillfully and creatively, organize teaching creatively, and integrate basic knowledge, basic technology, basic skills, and sports psychology with aesthetics; The content of dance movements is characterized by elegance and artistry, which requires high physical quality, and to some extent, causes certain learning difficulties for some students. In the process of teaching, the positive artistic mood of adjusting teaching mood and paying attention to teaching is a weak, calm and long-lasting emotional state, which has a pretty long duration. The teaching mood affects the teaching behavior of teachers and students and will make everything around them infected with this emotion. In teaching, some games will be interspersed. If the distribution is improper, it will cause psychological pressure on students and affect the teaching mood. Only in a positive and good teaching mood can teachers make teaching become a vibrant teaching whole full of vitality and vitality through reasonable organization and distribution, which has a soul-stirring and shocking artistic charm. The guidance of self-confidence and the establishment of teachers’ praise, encouragement and psychological suggestion can arouse students’ self-confidence, stimulate their potential and meet students’ needs for love and respect. The rational use of motivation and strengthening the art of teaching motivation can fully mobilize students’ enthusiasm for learning. Teachers can also use praise as an auxiliary teaching evaluation art. The so-called evaluation art refers to the PE teachers’ assessment of students’ mastery of teaching content and the teacher’s recognition of students. It is essential to assess each student with respect appropriately. How to evaluate poor students and improving their academic performance should be the teaching focus of PE teachers. Teachers must teach these students patiently in the principle of care, love and encouragement, and pay attention to the improvement process in evaluating their learning effect so that these students can see their progress and enhance their self-confidence.Of course, achieving the above teaching art means understanding the students’ mentality. Therefore, this article uses wearable bracelets to monitor the students’ heart rates based on the current equipment characteristics to achieve action recognition in dance teaching and learning. On the one hand, it makes up for the shortcomings of video signal blocking and signal instability; on the other hand, it hopes to evaluate the students’ psychological state through heart rate monitoring. By comparing the natural heart rate with the standard and relaxed heart rate, we can analyze their psychological tension and make predictions about their physical fitness to achieve a win-win situation for mental and physical fitness evaluation. The adaptive fusion recognition method combined graph convolution network and LSTM model used in this article has a higher longitude. Mutual recognition is more robust than the traditional convolution network and the different learning methods based on machine learning. At present, psychoanalysis based on heart rate can only conduct a preliminary study on the psychological state; that is, it can judge the most fundamental tension and relaxation state and cannot achieve emotional calculation. With the development of science and technology, it will have a better effect to conduct a deeper multi-mode fusion analysis of video data with portable EEG, ECG and other signals.This article proposes an adaptive fusion classification model framework that integrates video technology and heart rate signals. The Openpose network is used to take the lead in extracting human skeleton motion features to ensure privacy. The extracted signals are formed into new video stream data, and the graph convolution network is used to complete the probability identification of actions. At the same time, the LSTM network is used to complete the probability identification of the heart rate data the other way, and the adaptive weight learning method is used to achieve the optimal classification decision. By comparing the classification results, the multi-mode fusion method used in this article has a higher recognition accuracy. At the same time, by observing the actual heart rate signal and the sliding variance signal, the psychological state of the dancers can be analyzed to realize the joint analysis of multimodal information in the teaching process and ensure the teaching effect. As single-mode information, the stability of heart rate signal and the impact of psychological state analysis are challenging to meet the needs of accurate analysis. Therefore, we hope to combine more modal information in future research to form a more precise analysis.10.7717/peerj-cs.1285/supp-1Supplemental Information 1Click here for additional data file.


Solar flares and coronal mass ejections, the primary space weather disturbances affecting the entire heliosphere and near-Earth environment, mainly emanate from sunspot regions harbouring high degrees of magnetic twist. However, it is not clear how magnetic helicity, the quantity for measuring the magnetic twist, is supplied to the upper solar atmosphere via the emergence of magnetic flux from the turbulent convection zone. Here, we report state-of-the-art numerical simulations of magnetic flux emergence from the deep convection zone. By controlling the twist of emerging flux, we find that with the support of convective upflow, the untwisted emerging flux can reach the solar surface without collapsing, in contrast to previous theoretical predictions, and eventually create sunspots. Because of the turbulent twisting of magnetic flux, the produced sunspots exhibit rotation and inject magnetic helicity into the upper atmosphere, amounting to a substantial fraction of injected helicity in the twisted cases that is sufficient to produce flare eruptions. This result indicates that the turbulent convection is responsible for supplying a non-negligible amount of magnetic helicity and potentially contributes to solar flares. The strongest events among these eruptions emanate from the solar active regions, in which the rotation and shear motions of strongly magnetised sunspots are often observed4. Once a solar flare occurs and a coronal mass ejection is launched, a helical magnetic flux rope is observed in the interplanetary space6, which is the clearest evidence that solar flares are the sudden release of the excessive magnetic energy accumulated in the helical magnetic structure in the solar corona through magnetic reconnection and plasma instability9.Solar flares and coronal mass ejections are the primary sources of space weather disturbances driving various plasma processes in the entire interplanetary space, including the near-Earth environmentA is the vector potential of a magnetic field B, i.e., 11,z denote the horizontal and vertical directions, respectively, are widely used in analyses of flare-productive active regions. For instance, observations show that active regions with a larger amount of magnetic helicity tend to produce stronger flares14 and that the activity level is enhanced in association with the total injected helicity or the temporal variation of helicity flux19. This is why magnetic helicity attracts broad attention of the solar and heliophysics community in the context of flare prediction and forecasting.Magnetic helicity is a measure to quantify the topology of a magnetic field, such as twists, kinks, and internal linkages:27. Therefore, investigating how magnetic helicity is accumulated in the corona as the magnetic flux emerges and builds up active regions is an important factor in understanding the occurrence of solar flares. However, it has almost never been considered how and to what extent the background convection affects the helicity injection, which is probably because we cannot probe the solar interior using direct optical observations. The detection of flux emergence in the convection zone using helioseismology is a promising technique but still in the development stage30.Based on a copious amount of observational evidence, it is widely believed that the injection of magnetic helicity into the corona is mainly due to the emergence of twisted magnetic flux from the convection zone and the consequential motions of sunspots, such as rotation and shearing31 and the references therein). Under the ideal condition with no background convection, even if the non-twisted flux tube reaches the photosphere, the helicity injection will be zero . In this study, we explore the occurrence of helicity injection by calculating the case with convection and, if so, to what extent.To solve this problem, we perform numerical simulations in which a twist-free magnetic flux tube emerges from the turbulent convection zone and examine whether the helicity injection into the upper atmosphere is negligibly small or comparable to the observations. Previous theoretical studies suggested that an untwisted emerging flux cannot reach the photosphere because it experiences counteracting aerodynamic drag , but the background convection field remains the same. The twist strengths of the weakly- and strongly-twisted tubes are 40, namely, these tubes are stable against the instability. In all three cases, the total magnetic flux in the axial direction is on the order of At mentclass2pt{minim31.Figure mentclass2pt{minim41. This situation agrees with the scenario where a single flux system emerges at multiple locations to build up a colliding bipolar sunspot43. The magnetic energy of the flux tube at the initial state is set to be the same for the three cases. However, once the sunspots are established in the photosphere, their decay is more rapid for the weaker twist cases because the local convection cells can more easily intrude into the sunspots and break them into pieces. In the twist-free case, the sunspots disappear by around From 45. Observations show that many more flaring active regions show rotations of bipolar sunspots in the same directions than in the opposite directions46. Of particular note, however, is that the sunspots in the no-twist case also exhibit rotations, with the negative sunspot in a clockwise direction and the positive sunspot in a counterclockwise direction  for the negative (positive) sunspot. This indicates that the local vortices streaming into the downflow plumes spin the magnetic pillars and drive the sunspot rotations in the photosphere. If the sunspot rotation is because of the release of magnetic twists, the two magnetic pillars (sunspots in the photosphere) should rotate in the same direction45. However, this is not the case. Thus, even if the flux tube is initially endowed with no magnetic twist, it is possible that the surrounding turbulent flow, in which the local vortices reside, exerts a spinning effect on the flux tube and, accordingly, the sunspot rotation occurs in the photosphere, leading to the significant injection of magnetic helicity into the upper atmosphere.Then, what effect causes a finite positive helicity injection in the non-twisted case? Fig. entclass1pt{minima49) for each HiFER patch near the polarity inversion line50. Top and middle panels of Fig. 50.One of the most promising methodologies that have been suggested to predict the flare eruptions is to analyse the spatial distribution of high free-energy regions (HiFERs), where the non-potential magnetic field, ility DAI9 for eacIn the strongly-twisted case, the HiFER patches  over time. This indicates that the sign of helicity injection in simulations with different background turbulence can be negative, which will be examined in the future studies.We investigate the physical mechanisms that provide magnetic helicity into the solar corona, which is critically important in understanding the occurrence of flare eruptions, by comparing the flux emergence simulations with and without magnetic twists under the existence of turbulent thermal convection. It is widely believed that the emergence of twisted flux tubes and associated sunspot rotations supply helicity into the active region corona. However, this is not trivial because of the lack of optical observations below the photosphere, which is the primary motivation of this study. We summarise the key results as follows. 51, and this could be due to the difference in vortex motions in the convection zone. Also, a considerable fraction of solar active regions do not obey the hemispheric helicity sign rule, with the fraction of violators being 20–40%53. This randomness may be the result of the stochastic imposing of magnetic helicity by the background turbulence to the twist of the emerging flux that is determined by the solar dynamo54.Asymmetry in sunspot rotation is reported in bipolar active regionsR2D232, which realistically simulates the thermal convection over the entire solar convection zone, to model the emergence of magnetic flux tubes and the spontaneous sunspot formation39. This code computes the 3D MHD equations with realistic radiation transfer and equation of state, and by implementing RSST58, it effectively suppresses the high sound speed in the deep solar interior and relaxes the Courant–Friedrichs–Lewy condition.In this study, we use the radiative MHD code 38, in which a magnetic flux tube emerges to successfully produce a bipolar sunspot group. The net kinetic helicity is negligibly small because the calculation box did not consider the solar rotation. The normalised net kinetic helicity at R2D2 simulations, which used the force-free magnetic flux tubes, we adopt commonly used Gaussian-type flux tubes, where the longitudinal and azimuthal components of the magnetic field are given byr, q are the axial field strength, radial distance from the tube axis, typical radius and twist intensity, respectively. We calculate three cases with varying q (Table q to be 0 or below the critical value for the kink instability 40, where We use a rectangular Cartesian box as the computational domain, spanning over mentclass2pt{minim59,We measure several physical quantities including the relative magnetic helicity (sing Eq. , and theentclass1pt{minima49. This instability is characterised by the parameter60. While the To investigate the flare productivity of the generated active regions, the instability analysis is performed based on the DAI theory, which states that a flux rope becomes unstable if it is sufficiently twisted and has a sufficient amount of magnetic flux against the overlying confinement field50, the coronal magnetic field is first calculated by the non-linear force-free field extrapolation based on the vector magnetic field of the photosphere. For the computational resources, the grid number was reduced from 50. For each HiFER, the critical area In the Supplementary Information.