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Background: Postural sway could be separated into several components according to frequencies. Higher frequency sway is indicative of hip strategy but how is it impaired in ataxia patients is still unknown. Methods: Static posturography examination were administered to 37 patients with spinocerebellar ataxia (SCA), 58 patients with the cerebellar type of multiple system atrophy and 53 healthy controls. Energy value trajectory during the four-step sensory organization tests were evaluated by generalized additive mixed model (GAMM). Repeated measures correlation analysis between energy value/proportions and postural performance (total postural sway, fall and tremor occurrence) were also performed. Results: GAMM analysis revealed that the middle frequency band proportion did not increase with test difficulties in MSA and SCA, indicating a failure of frequency shift. Repeated measures correlation analysis revealed that the highest correlation coefficient between energy values were found between MFV and HFV in healthy controls, illustrating components of a complete hip strategy, which was not found in SCA or MSA. In normal adults, there is a significant and positive relationship between MFP and HFP with total energy values, illustrating frequency shifts of normal stance. However, MFP was negatively related with total energy values in SCA (p>0.05) and MSA (pConclusion: Hip strategy was not complete in SCA while it was completely disrupted in MSA, which explains why there were more falls in MSA patients. High frequency band postural sway (>2Hz) is an important component of a complete hip strategy and its origin needs further investigation.

Gestodene (GES), altrenogest (ALT), and medroxyprogesterone acetate (MPA) are three potent synthetic progestins detected in agricultural soils; however, their biotransformation outcomes in soils remain unclear. This study explored the biotransformation of these progestins in five agricultural soils with different physicochemical properties. The biotransformation data were well-described by a first-order decay model (R

Nitrous oxide (N₂O) is a potent greenhouse gas that is released from agricultural ecosystems where nitrogen fertilizers are poorly used and contributes to global climate warming. Large nitrogen fertilizer inputs in summer maize fields on the North China Plain (NCP) lead to large N₂O emissions. N₂O emissions can be mitigated using 3,4‐dimethylpyrazole phosphate (DMPP), but the efficiency and microbial mechanisms of this mitigation at different nitrogen rates remain poorly understood. To evaluate the efficiency of N₂O emission mitigation by DMPP at different nitrogen rates and to explore its mechanisms at the microbial level, we monitored the dynamic changes in mineral and N₂O fluxes and analysed the abundance and community structure of ammonia oxidizers. We found that DMPP significantly inhibited the oxidation of ammonium (NH₄⁺) to nitrate (NO₃⁻) and thus maintained NH₄⁺ concentrations but decreased the peak value of NO₃⁻ concentrations. Total N₂O emissions were increased by 6.5‐fold, 13.2‐fold and 26.7‐fold in fields with 112.5 kg N ha⁻¹, 225 kg N ha⁻¹ and 337.5 kg N ha⁻¹, respectively, compared with fields with no nitrogen applied. Nitrogen increased the abundance of ammonia‐oxidizing bacteria (AOB) and decreased that of ammonia‐oxidizing archaea (AOA), whereas DMPP exhibited the opposite effects. Therefore, AOB could be the dominant N₂O emission contributors in nitrogen‐treated soils. Sequencing results suggested that all AOB belong to the Nitrosospira and Nitrosomonas nitrosa groups, and all AOA fell within the Nitrososphaera group. In both AOB and AOA communities, changes in the second‐largest cluster after the application of nitrogen fertilizer and DMPP were more pronounced than those in the largest cluster. The potential functional clusters of AOB and AOA were Nitrosospira cluster 3b and Nitrososphaera cluster 4.1, respectively. This study showed that nitrogen and DMPP both affected the abundance and structure of ammonia‐oxidizer communities, which may contribute to the variations in N₂O emissions from croplands. HIGHLIGHTS: Role of soil microorganisms in the efficiency of DMPP to reduce N₂O emissions under different N inputs was explored. N input increased N₂O emissions and DMPP reduced N₂O emissions N and DMPP affect N₂O emission via a changed key cluster of ammonia oxidizers. DMPP was more efficient at higher nitrogen input levels.

The dorsolateral prefrontal cortex (DLPFC) has been implicated in auditory–motor integration for accurate control of vocal production, but its precise role in this feedback-based process remains largely unknown. To this end, the present event-related potential study applied a transcranial magnetic stimulation (TMS) protocol, continuous theta-burst stimulation (c-TBS), to disrupt cortical activity in the left DLPFC as young adults vocalized vowel sounds while hearing their voice unexpectedly shifted upwards in pitch. The results showed that, as compared to the sham condition, c-TBS over left DLPFC led to significantly larger vocal compensations for pitch perturbations that were accompanied by significantly smaller cortical P2 responses. Source localization analyses revealed that this brain activity pattern was the result of reduced activation in the left superior frontal gyrus and right inferior parietal lobule (supramarginal gyrus). These findings demonstrate c-TBS-induced modulatory effects of DLPFC on the neurobehavioral processing of vocal pitch regulation, suggesting that disrupting prefrontal function may impair top–down inhibitory control mechanisms that prevent speech production from being excessively influenced by auditory feedback, resulting in enhanced vocal compensations for feedback perturbations. This is the first study that provides direct evidence for a causal role of the left DLPFC in auditory feedback control of vocal production.

Objective: To construct a comprehensive simulation framework of "gait-musculoskeletal system(MS)-finite element(FE)" for analysis of hip joint dynamics characteristics and the changes in the contact stress in the hip throughout a gait cycle.Methods:Two healthy volunteers (male and female) were recruited. The 3D gait trajectories during normal walking and the CT images including the hip and femur of the volunteers were obtained. CT Imaging data in the DICOM were extracted for subjected 3D hip joint reconstruction. The reconstructed 3D model files were used to realize the subject-specific registration of the pelvis and thigh segment of general musculoskeletal model. The captured marker trajectory data were used to drive subject-specific musculoskeletal model to complete inverse dynamic analysis. Results of inverse dynamic analysis were exported and appliedas boundary and load settings of the hip joint finite element in ABAQUS. Finally, the finite element analysis(FEA) was performed to analyze contact stress of hip joint during a gait cycle of left foot.Results: In the inverse dynamic analysis, the dynamic changes of the main hip-femoral muscle force with respect to each phase of a single gait cycle were plotted. The hip joint reaction force reached a maximum value of 2.9%BW（Body weight）and appeared at the end of the terminal stance phase. Twin peaks appeared at the initial contact phase and the end of the terminal stance phase respectively. FEA showed the temporal changes in contact stress in the acetabulum. In the visual stress cloud chart, the acetabular contact stress was mainly distributed in the dome of the acetabulum and in the anterolateral area at the top of the femoral head during a single gait cycle. The acetabular contact area was 293.8-998.4 mm2 and the maximum contact area appear at the mid-stance phase or the loading response phase of gait. The maximum contact stress of the acetabulum reached 6.91 Mpa (Model 1) / 6.92 Mpa(Model 2) at the terminal stance phase. Conclusions:The "Gait-MS-FE" technology is integrated to construct a comprehensive simulation framework. Based on human gait trajectories and their CT images, individualized simulation modeling can be achieved. Subject-specific gait in combination with an inverse dynamic analysis of the MS provides pre-processing parameters for FE simulation for more accurate biomechanical analysis of hip joint.

Objective To construct a comprehensive simulation method of “gait-musculoskeletal system (MS)-finite element (FE)” for analysis of hip joint dynamics characteristics and the changes in the contact stress in the hip throughout a gait cycle. Methods Two healthy volunteers (male and female) were recruited. The 3D gait trajectories during normal walking and the CT images including the hip and femur of the volunteers were obtained. CT imaging data in the DICOM format were extracted for subjected 3D hip joint reconstruction. The reconstructed 3D model files were used to realize the subject-specific registration of the pelvis and thigh segment of general musculoskeletal model. The captured marker trajectory data were used to drive subject-specific musculoskeletal model to complete inverse dynamic analysis. Results of inverse dynamic analysis were exported and applied as boundary and load settings of the hip joint finite element in ABAQUS. Finally, the finite element analysis (FEA) was performed to analyze contact stress of hip joint during a gait cycle of left foot. Results In the inverse dynamic analysis, the dynamic changes of the main hip-femoral muscle force with respect to each phase of a single gait cycle were plotted. The hip joint reaction force reached a maximum value of 2.9%BW (body weight) and appeared at the end of the terminal stance phase. Twin peaks appeared at the initial contact phase and the end of the terminal stance phase, respectively. FEA showed the temporal changes in contact stress in the acetabulum. In the visual stress cloud chart, the acetabular contact stress was mainly distributed in the dome of the acetabulum and in the anterolateral area at the top of the femoral head during a single gait cycle. The acetabular contact area was between 293.8 and 998.4 mm2, and the maximum contact area appear at the mid-stance phase or the loading response phase of gait. The maximum contact stress of the acetabulum reached 6.91 MPa for the model 1 and 6.92 MPa for the model 2 at the terminal stance phase. Conclusions The “Gait-MS-FE” technology is integrated to construct a comprehensive simulation framework. Based on human gait trajectories and their CT images, individualized simulation modeling can be achieved. Subject-specific gait in combination with an inverse dynamic analysis of the MS provides pre-processing parameters for FE simulation for more accurate biomechanical analysis of hip joint. Graphical abstract

Nitrous oxide (N2O) is a pollutant released from agriculture soils following N fertilizer application. N stabilizers, such as N-(n-butyl) thiophosphoric triamide (NBPT) and 3,4-dimethylpyrazole phosphate (DMPP) could mitigate these N2O emissions when applied with fertilizer. Here, field experiments were conducted to investigate the microbial mechanisms by which NBPT and DMPP mitigate N2O emissions following urea application. We determined dynamic N2O emissions and inorganic N concentrations for two wheat seasons and combined this with metagenomic sequencing. Application of NBPT, DMPP, and both NBPT and DMPP together with urea decreased mean N2O accumulative emissions by 77.8, 91.4 and 90.7%, respectively, compared with urea application alone, mainly via repressing the increase in NO2- concentration after N fertilization. Sequencing results indicated that urea application enriched microorganisms that were positively correlated with N2O production, whereas N stabilizers enriched microorganisms that were negatively correlated with N2O production. Furthermore, compared to urea application alone, NBPT with urea reduced the abundances of genes related to denitrification, including napA/nasA, nirS/nirK, and norBC, resulting in a higher soil NO3- pool. Conversely, DMPP application, either alone or together with NBPT, decreased the abundance of genes involved in ammonia oxidation and denitrification, including amoCAB, hao, napA/nasA, nirS/nirK, and norBC, and maintained a greater soil NH4+ pool. Both N stabilizers resulted in similar abundances of nirABD-which is related to NO2- reducers-as when no N fertilizer was applied, which could prevent NO2- accumulation, consequently mitigating N2O emissions. These findings suggest that the high effectiveness of N stabilizers on mitigating N2O emissions could be attributed to changes to soil microbial communities and N-cycling functional genes to control the by-product or intermediate products of microbial N-cycling processes in agricultural soils.

The aim of this study is to evaluate the prevalence and electrophysiological features of 3-Hz postural tremor in multiple system atrophy-cerebellar type and spinocerebellar ataxia. A static posturography examination was administered to 37 persons with spinocerebellar ataxia, 58 others with the cerebellar type of multiple system atrophy, and 53 healthy controls. During the sensory organization tests of 5 multiple system atrophy patients, surface electromyograms were recorded from bilateral tibialis anterior and medial gastrocnemius muscles. The patients with multiple system atrophy had, on average, significantly higher scores on the International Cooperative Ataxia Rating Scale and significantly greater prevalence of cross sign. Almost 80% of them fell during the posturography testing compared with two-thirds of the spinocerebellar ataxia patients. Twenty-seven percent of the spinocerebellar ataxia patients and 82.8% of those with multiple system atrophy displayed postural tremor with a frequency of approximately 3 Hz. The tremor’s frequency tended to be lower in the spinocerebellar ataxia patients. The surface electromyography revealed highly coherent tremor activity at about 3 Hz in the patients’ bilateral tibialis anterior and alternating firing in the bilateral antagonist muscles. Combining cross sign with a subject’s static score of the International Cooperative Ataxia Rating Scale and occurrence of the tremor produced an indicator able to differentiate the two conditions with a sensitivity of 87.9% and a specificity of 89.2%. The area under the receiver operating characteristics curve for the indicator was 0.942. Three-hertz postural tremor is relatively characteristic of cerebellar type of multiple system atrophy and appears at an early stage of the disease. Identification of the tremor by posturography will facilitate its diagnosis.