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The posterior superior temporal gyrus (pSTG) has been implicated in the integration of auditory feedback and motor system for controlling vocal production. However, the question as to whether and how the pSTG is causally involved in vocal feedback control is currently unclear. To this end, the present study selectively stimulated the left or right pSTG with continuous theta burst stimulation (c-TBS) in healthy participants, then used event-related potentials to investigate neurobehavioral changes in response to altered auditory feedback during vocal pitch regulation. The results showed that, compared to control (vertex) stimulation, c-TBS over the right pSTG led to smaller vocal compensations for pitch perturbations accompanied by smaller cortical N1 and larger P2 responses. Enhanced P2 responses received contributions from the right-lateralized temporal and parietal regions as well as the insula, and were significantly correlated with suppressed vocal compensations. Surprisingly, these effects were not found when comparing c-TBS over the left pSTG with control stimulation. Our findings provide evidence, for the first time, that supports a causal relationship between right, but not left, pSTG and auditory-motor integration for vocal pitch regulation. This lends support to a right-lateralized contribution of the pSTG in not only the bottom-up detection of vocal feedback errors but also the involvement of driving motor commands for error correction in a top-down manner.

As a clean, low-carbon, efficient and renewable energy source, hydrogen has gradually become an important energy carrier to combat climate change and achieve sustainable development in the world. China is now facing the stress of realizing the carbon peak and carbon neutrality goals, where hydrogen will play a significant role. Against this backdrop, to develop China's hydrogen strategy under the carbon peak and carbon neutrality goals, this paper explores the hydrogen resource endowment in China, presents the concepts such as Hydrogen Ethics and the Hu's Hydrogen Line, and discusses the status quo and existing advantages in hydrogen production, storage, transport and utilization in China. Six major obstacles and challenges that China's hydrogen energy industry is facing are pointed out, i.e. cost problem, inadequate hydrogen infrastructures, low energy efficiency mismatching the development progress of renewable energy, insufficient market demand, shortcomings in technology, and imperfect policy system. Finally, five policy suggestions for the future development of China's hydrogen energy industry are proposed as follows: (1) make an action plan as a response to the national hydrogen development plan; (2) build an international and domestic double-cycle hydrogen economic system; (3) incorporate hydrogen into the establishment of a clean, low-carbon, safe and efficient energy system; (4) accelerate the technological innovation to form advanced hydrogen technologies; and (5) construct hydrogen-oriented industrial clusters/parks to expand the hydrogen utilization market. It is concluded that for meeting the carbon peak and carbon neutrality goals, China should leverage the dual advantages of hydrogen as an energy carrier and an industrial raw material, allowing the hydrogen industry to play a synergistic role in ensuring the country's energy security, promoting the socio-economic transformation and upgrading, and protecting the ecological environment, thereby providing a technical option and support for China to achieve the ultimate goal of carbon neutrality.

BackgroundAccumulating evidence has shown significant contributions of the right cerebellum to auditory-motor integration for vocal production. Whether the left cerebellum is likewise involved in vocal motor control, however, remains unclear.MethodsBy applying neuronavigated continuous and intermittent theta burst stimulation (cTBS/iTBS) over the left cerebellar lobule VII (Crus I), the present event-related potential (ERP) study investigated whether the left cerebellum exerts causal effects in modulating auditory feedback control of vocal pitch production. After receiving cTBS, iTBS, or sham stimulation over the left cerebellum, a group of fifteen young adults produced sustained vowels while hearing their voice unexpectedly shifted in pitch upwards or downwards by 200 cents. The effects of cerebellar stimulation were assessed by measuring the vocal and ERP (N1/P2) responses to pitch perturbations across the conditions.ResultsWhen compared to sham stimulation, cTBS or iTBS over the left cerebellar lobule VII (Crus I) led to no systematic changes in vocal compensations for pitch perturbations in auditory feedback. Also, the cortical N1/P2 responses did not vary significantly across the three stimulation sessions.ConclusionThese findings present the first neurobehavioral evidence suggesting that the left cerebellum is not causally associated with auditory feedback control of vocal production. Together with previously reported causal effects of the right cerebellum in modulating vocal pitch regulation, the present study lends support to the hypothesis that there is a functional lateralization of the cerebellum in vocal motor control though auditory feedback.

The supplementary motor area (SMA) has been implicated in the feedforward control of speech production. Whether this region is involved in speech motor control through auditory feedback, however, remains uncertain. The present event-related potential (ERP) study examined the role of the left SMA in vocal pitch regulation in a causal manner by combining auditory feedback manipulations and neuronavigated continuous theta bust stimulation (c-TBS). After receiving c-TBS over the left SMA or the control site (vertex), twenty young adults vocalized the vowel sound /u/ while hearing their voice unexpectedly pitch-shifted -50 or -200 cents. Compared to the control stimulation, c-TBS over the left SMA led to decreased vocal compensations for pitch perturbations of -50 and -200 cents. A significant decrease of N1 and P2 responses to -200 cents perturbations was also found when comparing active and control stimulation. Major neural generators of decreased P2 responses included the right-lateralized superior and middle temporal gyrus and angular gyrus. Notably, a significant correlation was found between active-control differences in the vocal compensation and P2 responses for the -200 cents perturbations. These findings provide neurobehavioral evidence for a causal link between the left SMA and auditory-motor integration for vocal pitch regulation, suggesting that the left SMA receives auditory feedback information and mediates vocal compensations for feedback errors in a bottom-up manner.

Sedum sarmentosum (Sedi Herba) has traditionally been used to treat jaundice and various types of liver disease. This study aimed to clarify the anti-cholestatic efficacy and the mechanism of S. sarmentosum ethyl acetate extract (SDEAE), as well as to screen the potential compounds with FXR activation. SDEAE effectively ameliorated ANIT-induced cholestasis in rats, as evidenced by the ameliorative histopathology of the liver and the significant decrease in biochemical markers (ALT, AST, ALP, GGT, TBIL, DBIL and TBA). The analysis of bile acid profile by LC–MS indicated that SDEAE decreased the toxic bile acid levels (TCA, TMCA and CA). Western blotting indicated that SDEAE activated FXR-associated pathway, thereby upregulating FXR, SHP, BSEP and UGT2B4 expression, and downregulating CYP7A1 and NTCP expression. Twenty-three compounds (7 nor-sesquiterpenoids, 13 flavonoids, 1 lignin, 1 sterol and 1 anthraquinone) were isolated and identified from SDEAE by comparing NMR data with the literature. The HPLC profiles of SDEAE and isolated compounds were also compared. High-content analysis showed that eight compounds (6, 7, 8, 11, 12, 13, 14 and 23) could activate FXR and compound 8 exhibited the most potent activity (p

BackgroundLanguage recovery is limited in moderate to severe post-stroke aphasia patients. Repetitive transcranial magnetic stimulation (rTMS) has emerged as a promising tool in improving language dysfunctions caused by post-stroke aphasia, but the treatment outcome is as yet mixed. Considerable evidence has demonstrated the essential involvement of the cerebellum in a variety of language functions, suggesting that it may be a potential stimulation target of TMS for the treatment of post-stroke aphasia. Theta burst stimulation (TBS) is a specific pattern of rTMS with shorter stimulation times and better therapeutic effects. The effect of continuous TBS (cTBS) on the cerebellum in patients with aphasia with chronic stroke needs further exploration.MethodsIn this randomized, sham-controlled clinical trial, patients (n = 40) with chronic post-stroke aphasia received 10 sessions of real cTBS (n = 20) or sham cTBS (n = 20) over the right cerebellar Crus I+ a 30-min speech-language therapy. The Western Aphasia Battery (WAB) serves as the primary measure of the treatment outcome. The secondary outcome measures include the Boston Diagnostic Aphasia Examination, Boston Naming Test and speech acoustic parameters. Resting-state fMRI data were also obtained to examine treatment-induced changes in functional connectivity of the cerebro-cerebellar network. These outcome measures are assessed before, immediately after, and 12 weeks after cerebellar cTBS intervention.DiscussionThis protocol holds promise that cerebellar cTBS is a potential strategy to improve language functions in chronic post-stroke aphasia. The resting-state fMRI may explore the neural mechanism underlying the aphasia rehabilitation with cerebellar cTBS.

Abstract This paper presents an open‐switch fault detection, and identification method for a neutral‐point clamped rectifier system. A new calculation method for phase‐to‐phase pole voltage deviations is proposed for reducing calculation errors. In this way, the more accurate diagnosis can be achieved. Both single‐switch faults, and multiple‐switch faults can be identified effectively by using fewer diagnostic variables, which makes the diagnostic method simpler, and more reliable. And all the variables can be simply calculated by signals which are available to the control system of the rectifier, avoiding the use of additional hardware. Moreover, different voltage thresholds are designed for different faulty feature sections to further reduce the diagnostic time. Additionally, a diagnostic result checking method is proposed to avoid the misdiagnosis when considering the effect of outer‐switch faults. Finally, experiments are carried out, and the results show the robustness, and effectiveness of the proposed method.

The open-switch fault of three-phase voltage source rectifiers (VSR) may lead to ac current distortion. In the past decade, some current-based fault diagnosis methods have been proposed, which directly used the phenomenon of current distortion but lacked a detailed analysis of the cause of it. In this paper, the current distortion of VSR with unity power factor operation is analyzed from two aspects: the effect of the three-phase switching state on the ac current and the response of the VSR control system after the fault. Besides, the impact of the VSR system and control parameters on the current distortion is also discussed. The analysis verifies the feasibility of the distortion current for fault diagnosis, providing a theoretical basis for current-based fault diagnosis methods of VSRs. To substantiate the analysis of the distorted current, we designed a simplified fault diagnosis method, which determined the faulty phase by the difference of the normalized three-phase distorted current, and located the faulty switch by the grid voltage angle. The experiments are conducted to verify the analysis of current distortion and the reliability of the proposed fault diagnosis method.