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Study designLow back pain (LBP) is a widespread clinical symptom affecting nearly all age groups and is a leading cause of disability worldwide. Degenerative changes in the spine and paraspinal tissues primarily contribute to the etiology of LBP.ObjectivesWe conducted this systematic review of animal models of paraspinal muscle (PSM) degeneration secondary to degenerative intervertebral disc (IVD), providing a comprehensive evaluation of PSM structural changes observed in these models at both macroscopic and microscopic levels.MethodsPubMed, EMBASE, Web of Science, Cochrane Library, and MEDLINE Ovid databases were searched through November 2023. Literature was sequentially screened based on titles, abstracts, inclusion of animal models and full texts. A manual search of reference lists from all eligible studies was also performed to identify any eligible article. Two independent reviewers screened the articles according to inclusion and exclusion criteria. The risk of bias was assessed using the Systematic Review Centre for Laboratory Animal Experimentation's Risk of Bias tool.ResultsA total of nine studies were included in the final analysis after a comprehensive screening process. The included studies were assessed for various aspects of the multifidus muscle. Given the limited number of studies and the substantial heterogeneity among them, a quantitative meta-analysis was deemed inappropriate.ConclusionsThis systematic review shows a comprehensive analysis of structural changes in the multifidus muscle in animal models of IVD degeneration and offers crucial insights for developing improved rodent models of IVD degeneration and assessing a battery of approaches for multifidus degeneration.

Objective To compare the efficacy of oblique lateral interbody fusion (OLIF), OLIF combined with anterolateral screw fixation (OLIF-AF), and OLIF combined with percutaneous pedicle screw fixation (OLIF-PF) in the treatment of single-level or 2-level degenerative lumbar disease. Methods Between January 2017 and 2021, 71 patients were treated with OLIF and combined OLIF. The demographic data, clinical outcomes, radiographic outcomes, and complications were compared among the 3 groups. Results The operative time and intraoperative blood loss in the OLIF (p0.05) or between the OLIF and OLIF-AF groups (p>0.05). There were no significant differences in fusion rates, the incidence of complications, lumbar lordosis, anterior disc height, and cross-sectional area among the 3 groups (p>0.05). The OLIF-PF group had significantly lower rates of subsidence than the OLIF group (p

PurposeNo multi-center radiomics models have been built to predict delayed remission (DR) after transsphenoidal surgery (TSS) in Cushing’s disease (CD). The present study aims to build clinical and radiomics models based on data from three centers to predict DR after TSS in CD.MethodsA total of 122 CD patients from Peking Union Medical College Hospital, Xuanwu Hospital, and Fuzhou General Hospital were enrolled between January 2000 and January 2019. The T1-weighted gadolinium-enhanced MRI images and clinical data were used as inputs to build clinical and radiomics models. The regions of interest (ROI) of MRI images were automatically defined by a deep learning algorithm developed by our team. The area under the curve (AUC) of receiver operating characteristic (ROC) curves was used to evaluate the performance of the models. In total, 10 machine learning algorithms were used to construct models.ResultsThe overall DR rate is 44.3% (54/122). According to multivariate Logistic regression analysis, patients with higher BMI and lower postoperative cortisol levels are more likely to achieve a higher rate of delayed remission. Among the 10 models, XGBoost achieved the best performance among all models in both clinical and radiomics models with AUC values of 0.767 and 0.819 respectively. The results from SHAP value and LIME algorithms revealed that postoperative cortisol level (PoC) and BMI were the most important features associated with DR.ConclusionRadiomics models can be built as an effective noninvasive method to predict DR and might be useful in assisting neurosurgeons in making therapeutic plans after TSS for CD patients. These results are preliminary and further validation in a larger patient sample is needed.

The J-TEXT capability is enhanced compared to two years ago with several upgrades of its diagnostics and the increase of electron cyclotron resonance heating (ECRH) power to 1 MW. With the application of electron cyclotron wave (ECW), the ECW assisted plasma startup is achieved; the tearing mode is suppressed; the toroidal injection of 300 kW ECW drives around 24 kA current; fast electrons are generated with toroidal injected ECW and the runaway current conversion efficiency increases with ECRH power. The mode coupling between 2/1 and 3/1 modes are extensively studied. The coupled 2/1 and 3/1 modes usually lead to major disruption. Their coupling can be either suppressed or avoided by external resonant magnetic perturbation fields and hence avoids the major disruption. It is also found that the 2/1 threshold of external field is significantly reduced by a pre-excited 3/1 mode, which can be either a locked island or an external kink mode. The disruption control is studied by developing prediction methods capable of cross tokamak application and by new mitigation methods, such as the biased electrode or electromagnetic pellet injector. The high-density operation and related disruptions are studied from various aspects. Approaching the density limit, the collapse of the edge shear layer is observed and such collapse can be prevented by applying edge biasing, leading to an increased density limit. The density limit is also observed to increase, if the plasma is operated in the poloidal divertor configuration or the plasma purity is increased by increasing the pre-filled gas pressure or ECRH power during the start-up phase.

Scrape-off layer (SOL) profiles and turbulence in ion cyclotron range of frequency (ICRF)-heated plasmas are investigated by the reciprocating probe diagnostic system (FRPs) and gas puff imaging (GPI) diagnostic in EAST. A radio-frequency (RF) sheath potential reaching up to 100 V is identified proximate to the ICRF antennas. Notably, the amplitude of this RF sheath potential escalates in response to rising ICRF power and inversely with plasma density. When a RF sheath is present in the far SOL, a pronounced density ‘shoulder’ forms in front of the ICRF antennas, while the ‘shoulder’ fade away as the antenna and associated RF sheath shift outwards. A strong E _r shear is revealed by measurements from both FRPs and GPI. Analysis of the poloidal wave number-frequency spectrum reveals suppression of high-frequency turbulence in the far SOL due to the RF sheath. This effect is manifested in the reduced autocorrelation time τ _c and reduced average blob size δ _blob of the SOL plasma. Intriguingly, the poloidal propagation direction of the low-frequency turbulence reverses from the electron to the ion diamagnetic drift direction at the RF sheath location. A surge of tungsten impurity is potentially attributed to the heightened interaction between the SOL plasmas and the wall material. Shifting the ICRF antennas outward, to alleviate heat spots, results in the relocation of the RF sheath to the shaded region of the main limiter. This shift amplifies the radial velocity of blobs in the far SOL and concurrently diminishes the SOL density when compared to conditions without ICRF injection. The properties of ion saturation current fluctuations are consistent with the stochastic model predictions.

Since the last IAEA-FEC in 2021, significant progress on the development of long pulse steady state scenario and its related key physics and technologies have been achieved, including the reproducible 403 s long-pulse steady-state H-mode plasma with pure radio frequency (RF) power heating. A thousand-second time scale (∼1056 s) fully non-inductive plasma with high injected energy up to 1.73 GJ has also been achieved. The EAST operational regime of high β _P has been significantly extended ( H _98y2 > 1.3, β _P ∼ 4.0, β _N ∼ 2.4 and n _e / n _GW ∼ 1.0) using RF and neutral beam injection (NBI). The full edge localized mode suppression using the n = 4 resonant magnetic perturbations has been achieved in ITER-like standard type-I ELMy H-mode plasmas with q _95 ≈ 3.1 on EAST, extrapolating favorably to the ITER baseline scenario. The sustained large ELM control and stable partial detachment have been achieved with Ne seeding. The underlying physics of plasma-beta effect for error field penetration, where toroidal effect dominates, is disclosed by comparing the results in cylindrical theory and MARS-Q simulation in EAST. Breakdown and plasma initiation at low toroidal electric fields (

In type I ELMy H-mode experiment, Edge localized mode (ELM) filaments are clearly captured by the high-speed vacuum ultraviolet imaging (VUVI) system which is developed on the Experimental Advanced Superconducting Tokamak. To analyze the ELM filament structures, the so-called singular value decomposition is performed on the imaging data to extract the key fluctuating components. In this work, the filament structure is characterized by the pitch angle and poloidal width. In a single ELM crash, it is found that the poloidal width increases (decreases) in the rise (decay) phase of the VUVI intensity induced by ELM crash. The pitch angle derived from the VUVI data agrees well with that calculated by the Equilibrium FITting code, indicating the filaments are aligned with the field lines. The poloidal velocity shows no obvious change during the rise and decay phases in an ELM crash. In addition, both the poloidal width and the poloidal velocity of the filament increase with the heating power. Since the filament structures are extracted from the line-integrated imaging data, all these results are obtained on the condition that the ELMs are confined to a narrow layer in the plasma.

Background: Resting‐state functional MRI (rs‐fMRI) has identified static changes of local brain activity among patients with intracerebral hemorrhage (ICH). However, the dynamic and concordance‐related characteristics of brain activity remain unclear. Purpose: To investigate static, dynamic, and concordance‐related features of the regional brain activity of young non‐disabled ICH patients. Study Type: Prospective. Subjects: Thirty‐three ICH patients (modified Rankin Scale score ≤2, 21% female, 46.36 ± 6.53) and 33 matched healthy controls (HCs) (21% female, 47.64 ± 6.16). Field Strength/Sequence: 3‐T, rs‐fMRI using gradient echo‐planar imaging, T1‐weighted imaging. Assessment: Neuropsychological and rs‐fMRI data were acquired from all participants. Amplitude of low‐frequency fluctuations (ALFF), fractional ALFF (fALFF), regional homogeneity (ReHo), voxel‐mirrored homotopic connectivity, global signal correlation (GSCorr) and degree centrality (DC), and their dynamic and concordance‐related changes with sliding window analysis were calculated based on rs‐fMRI data at a whole‐brain level. The burden of cerebral small vascular diseases (cSVD) was assessed by cSVD scores. All hemorrhage lesions were delineated on normalized T1 images. Statistical Tests: Multiple regression models, a voxel‐level uncorrected P < 0.001, a cluster‐level false discovery rate (FDR) corrected q < 0.05, a re‐corrected qFDR <0.05 were considered significant. Pearson or Spearman correlation analyses between fMRI data and neurocognitive performance were performed. Results: Compared to HCs, ICH patients showed significant abnormal changes of ALFF, dynamic ALFF, fALFF, ReHo, dynamic ReHo, GSCorr, DC, and voxel‐wise concordance in multiple brain regions mainly including the bilateral cerebellar hemispheres, ipsilesional thalamus, and bilateral middle cingulum gyrus. The ALFF in the cerebellar posterior lobe and thalamus were significantly associated with attention (r = −0.481) and executive function (rho = −0.521) in ICH patients. Data Conclusion: Young non‐disabled ICH patients exhibit static, dynamic, and concordance‐related alterations of local brain activity, part of which shows associations with cognitive functions. These findings may help comprehensively understand the mechanism of cognitive impairment after ICH. Level of Evidence: 2 Technical Efficacy: Stage 3 [ABSTRACT FROM AUTHOR]

Here we report a fully non-inductive H-mode operation with a sporadic-small-edge-localized mode(ELM)-dominant pedestal realized in EAST with a tungsten divertor, where the normalized electron collisionality at the pedestal top is estimated below unity. This is regarded as the expansion and/or supplement of our previous research having been preliminarily reported (section 4.2 in (B N Wan et al 2017 Nucl. Fusion57 102019)) in the EAST overview article contributed to the special issue on FEC 2016 summaries and overviews. In this operation, spontaneous avoidance of large ELMs is realized reproducibly, for the first time on EAST, at a lower collisionality (below unity) at the pedestal top, profiting from high heating power. Besides, this regime shows the well controlled bulk plasma density and light impurity concentration, good energy confinement with H98, (y2) ≃ 1, together with a loop voltage very close to zero. All of these features are considered critical to a steady-state operation with high performance, which EAST is on target to demonstrate in the near future in support to the International Thermonuclear Experimental Reactor (ITER). However, this operation regime suffers a continuous accumulation of medium-/high-Z impurities, which may seriously limit its sustainability. The resonant magnetic perturbation (RMP) with a dominant toroidal mode number n = 1 has been employed for assisting exhaust of heavy impurities, which is, unfortunately, not successful since the RMP with an effective poloidal spectrum always brings back large ELMs. This scenario transits to an ELM H-mode regime as plasma current is decreased, and elimination of large ELMs is well reproduced by ELITE simulation. Finally, we present a discussion on the potential mechanism eliminating large ELMs, which seems to highlight the LHW-induced profound change in edge magnetic topology. [ABSTRACT FROM AUTHOR]