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High-frequency repetitive transcranial magnetic stimulation (HF-rTMS) remains a promising strategy for neurorehabilitation. The stimulation intensity (SI) influences the after-effects observed. Here, we examined if single sessions of a HF-rTMS protocol, administered at different suprathreshold SI, can be safely administered to able-bodied (AB) individuals.Six right-handed men were included in this pilot study. HF-rTMS was delivered over the left M1, in 10 trains of 75 biphasic stimuli at 15 Hz, at 105 to 120% of the individual resting motor threshold (RMT). Participants and EMG were monitored to control for signs of spread of excitation and brief EMG burst (BEB) post-stimulation. TMS side-effects questionnaires and the numeric rating scale (NRS) were administered during each session. Additionally, we assessed CSE and motor performance changes with measures of resting (rMEP) and active (aMEP) motor evoked potential and grip strength and the Box and Block test (BBT) scores, respectively.Overall, the sessions were tolerated and feasible without any pain development. EMG analysis during HF-rTMS revealed increased BEB frequency with SI. Statistical models revealed an increase of CSE at rest (rMEP) but not during active muscle contraction (aMEP). No linear relationship was observed between HF-rTMS intensity and rMEP increase. No significant changes were highlighted for motor performance measures.Although feasible and tolerable by the AB tested, the results demonstrate that when administered at suprathreshold SI, 15 Hz-rTMS reveals signs of persistent excitation, suggesting that safety precautions and close monitoring of participants should be performed when testing such stimulation protocols.

ObjectiveThe current review was aimed to determine the effectiveness of mental imagery training (MIT) on the enhancement of maximum voluntary muscle contraction (MVC) force for healthy young and old adults.Data sourcesSix electronic databases were searched from July 2021 to March 2022. Search terms included: “motor imagery training,” “motor imagery practice,” “mental practice,” “mental training,” “movement imagery,” “cognitive training,” “strength,” “force,” “muscle strength,” “performance,” “enhancement,” “improvement,” “development,” and “healthy adults.”Study selection and data extractionRandomized controlled trials of MIT in enhancing muscle strength with healthy adults were selected. The decision on whether a study met the inclusion criteria of the review was made by two reviewers independently. Any disagreements between the two reviewers were first resolved by discussion between the two reviewers. If consensus could not be reached, then it would be arbitrated by a third reviewer.Data synthesisTwenty-five studies including both internal MIT and external MIT were included in meta-analysis for determining the efficacy of MIT on enhancing muscle strength and 22 internal MIT were used for subgroup analysis for examining dose-response relationship of MIT on MVC.ResultsMIT demonstrated significant benefit on enhancing muscle strength when compared with no exercise, Effect Size (ES), 1.10, 95% confidence interval (CI), 0.89–1.30, favoring MIT, but was inferior to physical training (PT), ES, 0.38, 95% CI, 0.15–0.62, favoring PT. Subgroup analysis demonstrated that MIT was more effective for older adults (ES, 2.17, 95% CI, 1.57–2.76) than young adults (ES, 0.95, 95% CI, 0.74–1.17), p = 0.0002, and for small finger muscles (ES, 1.64, 95% CI, 1.06–2.22) than large upper extremity muscles (ES, 0.86, 95% CI, 0.56–1.16), p = 0.02. No significant difference was found in the comparison of small finger muscles and large lower extremity muscles, p = 0.19 although the ES of the former (ES, 1.64, 95% CI, 1.06–2.22) was greater than that of the later (ES, 1.20, 95%, 0.88–1.52).ConclusionThis review demonstrates that MIT has better estimated effects on enhancing MVC force compared to no exercise, but is inferior to PT. The combination of MIT and PT is equivalent to PT alone in enhancing muscle strength. The subgroup group analysis further suggests that older adults and small finger muscles may benefit more from MIT than young adults and larger muscles.

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 105 and 109 GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

In this paper, a stable node-based smoothed finite element method with PML (SNS-FEM-PML) is proposed to solve the scattering problem of a time-harmonic elastic plane wave by a rigid obstacle in two dimensions. In the algorithm, the stability term is constructed by the Taylor expansion of the gradient to cure the instability of the original NS-FEM. The linear variations of the gradient with respect to x and y are included in the stability term, which are calculated using four integral points in an equivalent circle of node-based smoothing domain. Meanwhile, the perfectly matched layer (PML) technique is used to truncate the unbounded domain. Furtherly, the smoothed Galerkin weak formulations of SNS-FEM-PML model are derived and the linear algebra system with the linear smoothed gradient is constructed for the Navier equation and Helmholtz equations with coupled boundaries. Besides, we also prove theoretically the softening effect and convergence of the SNS-FEM model. Several numerical examples verify the effectiveness and accuracy of SNS-FEM model. The results suggest that the convergence order of L2 and H1 semi-norm errors of the SNS-FEM model is consistent with the theory of FEM, and convergence rate of the relative error is higher than that of the FEM.

Traumatic brain injury (TBI) often results in balance impairment, increasing the risk of falls, and the chances of further injuries. However, the underlying neural mechanisms of postural control after TBI are not well understood. To this end, we conducted a pilot study to explore the neural mechanisms of unpredictable balance perturbations in 17 chronic TBI participants and 15 matched healthy controls (HC) using the EEG, MRI, and diffusion tensor imaging (DTI) data. As quantitative measures of the functional integration and segregation of the brain networks during the postural task, we computed the global graph‐theoretic network measures (global efficiency and modularity) of brain functional connectivity derived from source‐space EEG in different frequency bands. We observed that the TBI group showed a lower balance performance as measured by the center of pressure displacement during the task, and the Berg Balance Scale (BBS). They also showed reduced brain activation and connectivity during the balance task. Furthermore, the decrease in brain network segregation in alpha‐band from baseline to task was smaller in TBI than HC. The DTI findings revealed widespread structural damage. In terms of the neural correlates, we observed a distinct role played by different frequency bands: theta‐band modularity during the task was negatively correlated with the BBS in the TBI group; lower beta‐band network connectivity was associated with the reduction in white matter structural integrity. Our future studies will focus on how postural training will modulate the functional brain networks in TBI., EEG connectivity graph measures were studied in traumatic brain injury (TBI) during the balance perturbation task. TBI group showed altered brain activation and connectivity during the balance task. Graph‐theoretic measures showed that the task modulation of brain network segregation in alpha‐band was reduced in TBI and the network segregation in theta‐band was associated with postural instability in TBI.

The aim of this study was to evaluate the effect of driving pressure (DP) guided ventilation strategy on the patients with mechanical ventilation in the hospital.The articles published in PubMed, the Cochrane Library, the China National Knowledge Information (CNKI), Wei Pu, Wan Fang database and Web of Science from inception to September 2021 were retrieved. The Q test and the I² statistic were used to assess statistical heterogeneity. Risks ratios (RR) with 95% confidence intervals (CI) were calculated for mortality.Seven studies (n=1,405 patients) were included. Five studies reported an adjusted Risk Ratio (RR) of mortality. Compared with the control group, the DP guided ventilation group was associated with a decreased mortality (RR 0.56; 95% confidence interval [CI], 0.39-0.79; p=0.001; I2 = 23%) using a fixed-effects model without significant heterogeneity. The control group had significantly higher driving pressure level than DP guided group (MD -3.03, 95%CI, -5.72 - -0.34, I2=100%, p=0.03); PaO2/FiO2 was significantly higher in DP guided group than in control group (MD 43.37; 95%CI, 12.58-74.15; I2=97%, p=0.006). There was no statistically significant difference in respiratory compliance, complications, platform pressure, duration of mechanical ventilation and the length of hospital stay between the DP guided group and the control group.The results suggested that the driving pressure guided ventilation strategy could decrease the mortality and increase oxygenation index (OI). However, further high-quality randomized controlled trials (RCTs) are needed to verify the impact of driving pressure on mechanically ventilated patients.

Urinary system tumors affect a huge number of individuals, and are frequently recurrent and progressing following surgery, necessitating lifelong surveillance. As a result, early and precise diagnosis of urinary system cancers is important for prevention and therapy. Histopathology is now the golden stan-dard for the diagnosis, but it is invasive, time-consuming, and inconvenient for initial diagnosis and re-gular follow-up assessment. Endoscopy can directly witness the tumor's structure, but intrusive detection is likely to cause harm to the patient's organs, and it is apt to create other hazards in frequently examined patients. Imaging is a valuable non-invasive and quick assessment tool; however, it can be difficult to define the type of lesions and has limited sensitivity for early tumor detection. The conventional approaches for detecting tumors have their own set of limitations. Thus, detection methods that combine non-invasive detection, label-free detection, high sensitivity and high specificity are urgently needed to aid clinical diagnosis. Optical diagnostics and imaging are increasingly being employed in healthcare settings in a variety of sectors. Raman scattering can assess changes in molecular signatures in cancer cells or tissues based on the interaction with vibrational modes of common molecular bonds. Due to the advantages of label-free, strong chemical selectivity, and high sensitivity, Raman scattering, especially coherent Raman scattering microscopy imaging with high spatial resolution, has been widely used in biomedical research. And quantity studies have shown that it has a good application in the detection and diagnosis of bladder can-cer, renal clear cell carcinoma, prostate cancer, and other cancers. In this paper, several nonlinear imaging techniques based on Raman scattering technology are briefly described, including Raman spectroscopy, coherent anti-Stokes Raman scattering, stimulated Raman scattering, and surface-enhanced Raman spectroscopy. And we will discuss the application of these techniques for detecting urologic malignancy. Future research directions are predicted using the advantages and limitations of the aforesaid methodologies in the research. For clinical practice, Raman scattering technology is intended to enable more accurate, rapid, and non-invasive in early diagnosis, intraoperative margins, and pathological grading basis for clinical practice.

The emphasis of risk has been recognized as a crucial component to effective and successful policy compliance amidst a crisis. Yet, during the COVID-19 pandemic, when the impact of risk may fluctua...

The use of aero-elastically tailored blades (ATB) for large wind turbines has shown the benefit of mitigating blade loads, in a passive adaptive manner, with the design of bend-twist coupling (BTC) along the blades. The BTC design makes the blades torsionally flexible and capable of adapting to different wind speeds. However, such increased flexibility makes the turbine modeling computationally demanding and the real-time controller design more challenging. In this work, to include the ATB effect into the turbine model for control, a twofold modeling for ATB characteristics is proposed. First a static BTC distribution is added to the turbine aerodynamics to account for the blade’s pre-bend-twist design, next a second-order transfer function is introduced to approximate the blade structural dynamic response to wind speed variations. The nonlinear model of the whole ATB wind turbine is built up in Simulink, linearized and discretized into a state-space form. A model predictive controller (MPC) is developed with the actuator constraints considered. Simulation studies are conducted on a 5MW ATB wind turbine at a selected above-rated wind speed. The use of the simplified model for control is assessed and the performance of MPC is compared to the gain-scheduling baseline controller.

Balance impairment or the loss of balance control is one of the most debilitating consequences of Traumatic Brain Injury (TBI). The levels of balance impairment may not be necessarily associated with the severity level of TBI, which makes it more difficult to do the correlational analysis of the balance impairment and its neural underpinnings. Therefore, we conducted a study where we collected the neurophysiological data (EEG and EMG) during a balance control task on a computerized posturography platform in a group of 17 TBIs and 15 age-matched healthy controls. Further, to distinguish balance-impaired TBIs (BI-TBI) from non-impaired TBIs (BN-TBI), we stratified the level of balance impairment using the Berg Balance Scale, a functional outcome measure widely used in both research and clinical settings. We computed the brain functional connectivity features between different cortical regions of interest using the imaginary part of coherence in different frequency bands. These features are then studied in a mean-centered Partial Least Squares Correlation analysis, which is a data-driven framework with the advantage of handling more features than the number of samples, thus making it suitable for a small-sample study. Based on the nonparametric significance testing using permutation and bootstrap procedure, we noticed that theta-band connectivity strength in the following ROIs significantly contributed to distinguishing balance impaired from non-impaired population: left middle frontal gyrus, right precuneus, right precentral gyrus, bilateral middle occipital gyrus, right middle temporal gyrus, left superior frontal gyrus, left post-central gyrus, right paracentral lobule. The knowledge of specific neural regions associated with balance impairment helps better understand neural mechanisms of TBI-associated balance dysfunction and may guide the development of novel therapeutic strategies, including targeted noninvasive brain stimulation. Our future studies will investigate the effects of balance platform training on sensorimotor connectivity.

There is a growing interest in non-invasive stimulation interventions as treatment strategies to improve functional outcomes and recovery after spinal cord injury (SCI). Repetitive transcranial magnetic stimulation (rTMS) is a neuromodulatory intervention which has the potential to reinforce the residual spinal and supraspinal pathways and induce plasticity. Recent reviews have highlighted the therapeutic potential and the beneficial effects of rTMS on motor function, spasticity, and corticospinal excitability modulation in SCI individuals. For this scoping review, we focus on the stimulation parameters used in 20 rTMS protocols. We extracted the rTMS parameters from 16 published rTMS studies involving SCI individuals and were able to infer preliminary associations between specific parameters and the effects observed. Future investigations will need to consider timing, intervention duration and dosage (in terms of number of sessions and number of pulses) that may depend on the stage, the level, and the severity of the injury. There is a need for more real vs. sham rTMS studies, reporting similar designs with sufficient information for replication, to achieve a significant level of evidence regarding the use of rTMS in SCI.

The East Asian experience in tackling COVID-19 has been highly praised, but this high-level generalisation neglects variation in pandemic response measures adopted across countries as well as the socio-political factors that shaped them. This paper compares the early pandemic response in Singapore and Hong Kong, two Asian city-states of similar sizes, a shared history of SARS, and advanced medical systems. Although both were able to contain the virus, they did so using two very different approaches. Drawing upon data from a cross-national, probability sample Internet survey conducted in May 2020 as well as media and mobility data, we argue that the different approaches were the result of the relative strength of civil society vs. the state at the outset of the outbreak. In protest-ridden Hong Kong, low governmental trust bolstered civil society, which focused on self-mobilisation and community mutual-help. In Singapore, a state-led response model that marginalised civil society brought early success but failed to stem an outbreak among its segregated migrant population. Our findings show that an active civil society is pivotal to effective outbreak response and that trust in government may not have been as important as a factor in these contexts.

International audience; Advances in the additive manufacturing (AM) processes have opened up the possibilities of widely using them in various structural sectors. Since 1980s this technology has been in permanent mutations. The ramification of the AM technology makes it difficult to obtain a clear impression of its potentialities. Predicting and controlling the mechanical characteristics of printed products is crucial for their final practical use. This study mainly aims to characterize the impact of printing parameters on the characteristics of printed articles and to evaluate their significance.

Objective of the study: This study aimed at characterizing output features of the higher-order motor control centers (hoMCCs), including secondary (premotor cortex [Pre] and supplementary motor area [SMA]) and association (prefrontal cortex [PFC]) motor regions to the primary motor cortex (M1) during graded force tasks. It is well known that one of the major roles of the primary motor cortex (M1) is controlling motor output such as muscle force. However, it is unclear how the hoMCCs interact with M1 in regulating voluntary muscle contractions. Methods: fMRI data was acquired during graded force tasks and fMRI-based effective connectivity (EC) and muscle force analyses were performed to study the relationship between hoMCCs-M1 effective connectivity and voluntarily exerted handgrip force. Results: The results show that there is a consistent information flow from the hoMCCs to M1 under all force conditions, suggesting a hierarchical control mechanism in the brain in regulating voluntary muscle force. Only the premotor cortex exhibited a significant role in mediating the level of force production through its EC with M1 but that role diminished when the exerted force was high, suggesting perhaps a ceiling and/or fatigue effect on the EC. A flip in the direction of EC from the primary sensory cortex (S1) to the hoMCCs (PFC, SMA, and Pre) at lower force levels while at higher forces EC was observed from the hoMCCs to S1. Conclusion: The hoMCCs regulate M1 output to produce desired voluntary muscle force. Only the Pre-to-M1 connectivity strength directly correlates with the force level especially from low to moderate levels. The hoMCCs are involved in modulating higher force production likely by strengthening M1 output and downgrading inhibition from S1 to M1.