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Yellow mushrooms ( Floccularia luteovirens ), which grow in high-altitude regions, are a component of traditional Tibetan medicine and have high nutritional value. In this study, the basic quality indices and volatile organic compounds (VOCs) of yellow mushrooms with different cap opening stages were determined. The volatile compounds (VOCs) were determined by headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) technology. The results demonstrated that as the degree of cap opening increased, both the weight of individual mushrooms and their respiratory intensity exhibited an upward trend. However, there was no significant difference in firmness, and the color change was not obvious. A total of 99 VOCs were detected in yellow mushrooms. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) successfully differentiated the three groups of yellow mushrooms based on VOCs, indicating the presence of differentially volatile organic compounds (DVOCs) among the groups. Further, through orthogonal partial least squares discriminant analysis (OPLS-DA), hierarchical cluster analysis (HCA), venn diagram and K-means cluster analysis, the intergroup DVOCs and the specific high-abundance DVOCs were obtained. It revealed the differences in VOCs of yellow mushrooms with different cap opening stages, providing theoretical data for further exploring the quality changes of yellow mushrooms during storage and the traceability of their origin.

A share-point is a cutting edge of the ploughshare, the crucial component of a horizontally reversible plough (HRP). Our previous trials in sandy loam soil indicated that severe abrasion/attrition wear with white materials appeared at the share-point section in the high-speed shifting tillage operation of the HRP. This mechanical fatigue was demonstrated to be caused by the flowing soil-tool interaction. But whether the white materials are associated with the thermal effects due to the high-speed tillage is not known. This paper extended our previous work to evaluate the thermal effects by using a combined multi-body dynamics analysis (MDA) and fluid–solid-thermal simulation. The dynamic interaction between soil and share-point was studied with the MDA approach. Based on the generated tillage forces through the MDA, a fluid–solid-thermal model of the ploughshare was developed to investigate the specific quantitative results, maximum stresses and temperatures observed at the share-point, which were further compared with the published worn-lands at the same tillage conditions (such as tillage speed and depth). The comparisons showed that the maximum coupled stresses and tillage temperatures in this study both appeared at the share-point, particularly at the most severe abrasion/attrition section with white materials, and that they were both varied with the different working conditions or the different tillage behaviours. Our findings demonstrate that the high-speed shifting operation of HRP has the thermal effects on the share-point wear due to the fact that the greatly varied tillage temperatures can accelerate to impact the surface integrity because of the thermal stresses detrimental to the micro-shape or size shape at the share-point section. This result may add to the knowledge base usefully applicable to the design of the high-speed mouldboard.

Smooth cross-section and consistent stubble height are of importance for retained stalk quality of leek. The commonly-used cutting tools are prone to suffer from severe friction due to their high-speed rotation on the rough field ground. Surely, the high-speed rotation results in not only violent worn on the blade tip but also uneven cross-section and inconsistent stubble height. This study proposed to develop an innovative modular cutting tool based on the indexable mechanism in mechanical engineering for either improving the retained stalk quality or prolonging the tool life. Firstly, the discrete element model for the leek stalk was calibrated using shear tests, with a minimal relative error of 0.36% observed for the peak cutting force. The coupled DEM-MBD simulation method was employed to analyze interaction forces and failure forms of the leek stalks during the cutting process, optimizing blade angle of the modular cutting tool. The optimized modular cutting tool reduced peak force compared with the conventional rotary tool and unoptimized modular cutting tool (by 34% and 16%, respectively). Results of the bench test show that the optimized modular cutting tool reduced tip breakage rate and incomplete cutting rate of retained stalks by 75% and 50%, respectively, but increased the oblique cutting rate by 33% relative to the conventional rotary tool. Additionally, the corrected smoothness index ( ) of cross-section was improved by 53.95%. These results highlight the potential of the modular cutting tool to improve harvesting efficiency and stalk quality in field applications.

Aims While acute itch comprises histamine‐dependent and ‐independent subtypes, critical mechanisms underlying histamine‐independent itch remain poorly understood. This study investigates the role of paired‐like homeobox 2a (Phox2a) in tachykinin 1‐positive (Tac1+) neurons of the lateral spinal nucleus (LSN) as a novel target for histamine‐independent pruritus intervention. Methods We combined chemogenetic manipulation (viral‐mediated neuronal activation/inhibition), whole‐cell patch‐clamp recordings, immunohistochemistry, fluorescence in situ hybridization, Western blotting, and behavioral assays to investigate the role of LSNTac1 neurons and Phox2a in itch modulation. Results LSNTac1 neurons were specifically activated during chloroquine (CQ)–induced histamine‐independent itch. Chemogenetic activation of these neurons exacerbated scratching, whereas inhibition suppressed itch behavior. Notably, Phox2a, expressed in LSNTac1 neurons, was downregulated during CQ‐induced itch. Overexpression of Phox2a in LSNTac1 neurons significantly alleviated CQ‐evoked scratching and was accompanied by a reduction in spontaneous excitatory postsynaptic currents (sEPSCs) amplitude without a change in sEPSCs frequency. Conclusions Our findings identify Phox2a in LSNTac1 neurons as a selective regulator of histamine‐independent acute itch through presynaptic excitability. This highlights Phox2a as a novel therapeutic target for histamine‐independent pruritus intervention. Phox2a expression in LSNTac1 neurons is selectively reduced in chloroquine‐induced itch. Overexpression of Phox2a alleviates this itch by the amplitude of spontaneous excitatory postsynaptic currents, revealing a potential treatment target for histamine‐independent pruritus.

Diabetic cardiomyopathy (DCM) is a form of idiopathic heart disease, with signs including hypertrophy of myocardial cells, hypertension-independent fibrosis and coronary artery disease. Considering the involvement of dimethylarginine dimethylaminohydrolase 2 (DDAH2) in diabetes, it was hypothesized that DDAH2 may be beneficial to cardiac function and myocardial fibrosis during the progression of DCM with involvement of the DDAH/asymmetric NG, NGdimethyl-L-arginine (ADMA)/nitric oxide synthase (NOS)/nitric oxide (NO) signaling pathway. Following establishment of diabetic rat models, diabetes-related blood biochemical indices and cardiac function were measured in diabetic rats treated with lentivirus expressing DDAH2, short hairpin RNA against DDAH2, or L-NNA (inhibitor of NOS) to identify the roles of DDAH2 in DCM. The functional roles of DDAH2 in DCM were further determined through detection of the levels of collagen I, matrix metalloproteinase 2 (MMP2) and tissue inhibitor of metalloproteinase 2 (TIMP2). The H9C2 myocardial cell line was selected for in vitro experiments. The effects of DDAH2 on the migration of myocardial cells under high glucose conditions were also examined. To further investigate the underlying regulatory mechanism of DDAH2 in DCM, the contents of ADMA and NO, and the activities of DDAH and NOS were observed. The DCM model rats treated with DDAH2 exhibited reduced left ventricular end-diastolic pressure, and decreased blood glucose, total cholesterol, triglyceride, fasting blood glucose, and fasting insulin levels, but exhibited increased left ventricular systolic pressure and maximum rate of left ventricular pressure rise/fall levels in myocardial tissues. Myocardial cells under high glucose conditions treated with DDAH2 showed reductions in collagen I, MMP2 and TIMP2, indicating that DDAH2 reduced cell migration. Decreased levels of ADMA and NO but increased levels of DDAH and NOS were observed following treatment with DDAH2, indicating that the DDAH/ADMA/NOS/NO pathway was activated. These results reveal that the overexpression of DDAH2 attenuates myocardial fibrosis and protects against DCM through activation of the DDAH/ADMA/NOS/NO pathway in DCM rats. These results indicate that DDAH2 is a potential therapeutic candidate for the treatment of DCM.

Background Tuberculosis poses a severe threat to human health. At present, compared with the traditional diagnostic methods for tuberculosis pleural effusion, such as Löwenstein–Jensen culture, pleural biopsy, and Ziehl–Neelsen smear microscopy, Xpert MTB/RIF was regarded as an emerging technology for its efficiency. The Xpert MTB/RIF accuracy for tuberculous pleural effusion diagnosis was evaluated in this systematic study. Materials and methods We searched the relevant literature published before January 2021 in PubMed, Cochrane, EMBASE, and Web of Science databases. Utilizing Review Manager 5.3 software, the quality of the included literature was evaluated based on the Quality Assessment of Diagnostic Accuracy Studies criteria. Sensitivity, specificity, and the summary receiver operating characteristic curves were plotted and analyzed with Metadisc 1.40 software. We used Stata 12.0 software to evaluate the publication bias of this study. Results Eighteen articles were identified in total. The sensitivity of Xpert MTB/RIF in the pleural effusion was 0.24, and specificity was 1.00, respectively. The area under the summary receiver operating characteristic curve was 0.9737, which indicated that the overall accuracy of the Xpert MTB/RIF was high. In addition, based on the Deeks funnel plot, no publication bias of the study was found. Conclusion Xpert MTB/RIF is a rapid method with high specificity but relatively low sensitivity for detecting Mycobacterium tuberculosis in pleural effusion. Its less sensitivity made it difficult to be used clinically, but the high specificity suggests that it can be used as a specific diagnostic method for tuberculous pleural effusion. SROC curve was plotted, and the following parameters were obtained: AUC of 0.9737 and Q of 0.9260 (SE = 0.0512). The SROC turn was near the top left corner, and the AUC was close to 1, which suggested that Xpert MTB/RIF had a comparatively overall high diagnostic accuracy for pleural effusion.

Previous studies in small samples have identified inconsistent cortical abnormalities in major depressive disorder (MDD). Despite genetic influences on MDD and the brain, it is unclear how genetic risk for MDD is translated into spatially patterned cortical vulnerability. Here, we initially examined voxel-wise differences in cortical function and structure using the largest multi-modal MRI data from 1660 MDD patients and 1341 controls. Combined with the Allen Human Brain Atlas, we then adopted transcription-neuroimaging spatial correlation and the newly developed ensemble-based gene category enrichment analysis to identify gene categories with expression related to cortical changes in MDD. Results showed that patients had relatively circumscribed impairments in local functional properties and broadly distributed disruptions in global functional connectivity, consistently characterized by hyper-function in associative areas and hypo-function in primary regions. Moreover, the local functional alterations were correlated with genes enriched for biological functions related to MDD in general (e.g., endoplasmic reticulum stress, mitogen-activated protein kinase, histone acetylation, and DNA methylation); and the global functional connectivity changes were associated with not only MDD-general, but also brain-relevant genes (e.g., neuron, synapse, axon, glial cell, and neurotransmitters). Our findings may provide important insights into the transcriptomic signatures of regional cortical vulnerability to MDD. Our combined large-scale neuroimaging and brain transcriptome study demonstrates genetic substrates underlying cortical functional abnormalities in depression, suggesting transcriptomic decoding of regional cortical vulnerability to depression.

Major depressive disorder (MDD) is common and disabling, but its neuropathophysiology remains unclear. Most studies of functional brain networks in MDD have had limited statistical power and data analysis approaches have varied widely. The REST-meta-MDD Project of resting-state fMRI (R-fMRI) addresses these issues. Twenty-five research groups in China established the REST-meta-MDD Consortium by contributing R-fMRI data from 1,300 patients with MDD and 1,128 normal controls (NCs). Data were preprocessed locally with a standardized protocol before aggregated group analyses. We focused on functional connectivity (FC) within the default mode network (DMN), frequently reported to be increased in MDD. Instead, we found decreased DMN FC when we compared 848 patients with MDD to 794 NCs from 17 sites after data exclusion. We found FC reduction only in recurrent MDD, not in first-episode drug-naïve MDD. Decreased DMN FC was associated with medication usage but not with MDD duration. DMN FC was also positively related to symptom severity but only in recurrent MDD. Exploratory analyses also revealed alterations in FC of visual, sensory-motor, and dorsal attention networks in MDD. We confirmed the key role of DMN in MDD but found reduced rather than increased FC within the DMN. Future studies should test whether decreased DMN FC mediates response to treatment. All R-fMRI indices of data contributed by the REST-meta-MDD consortium are being shared publicly via the R-fMRI Maps Project.

Aberrant topological organization of whole-brain networks has been inconsistently reported in studies of patients with major depressive disorder (MDD), reflecting limited sample sizes. To address this issue, we utilized a big data sample of MDD patients from the REST-meta-MDD Project, including 821 MDD patients and 765 normal controls (NCs) from 16 sites. Using the Dosenbach 160 node atlas, we examined whole-brain functional networks and extracted topological features (e.g., global and local efficiency, nodal efficiency, and degree) using graph theory-based methods. Linear mixed-effect models were used for group comparisons to control for site variability; robustness of results was confirmed (e.g., multiple topological parameters, different node definitions, and several head motion control strategies were applied). We found decreased global and local efficiency in patients with MDD compared to NCs. At the nodal level, patients with MDD were characterized by decreased nodal degrees in the somatomotor network (SMN), dorsal attention network (DAN) and visual network (VN) and decreased nodal efficiency in the default mode network (DMN), SMN, DAN, and VN. These topological differences were mostly driven by recurrent MDD patients, rather than first-episode drug naive (FEDN) patients with MDD. In this highly powered multisite study, we observed disrupted topological architecture of functional brain networks in MDD, suggesting both locally and globally decreased efficiency in brain networks.

Emotional regulation is known to be associated with activity in the amygdala. The amygdala is an emotion-generative region that comprises of structurally and functionally distinct nuclei. However, little is known about the contributions of different frontal-amygdala sub-region pathways to emotion regulation. Here, we investigated how functional couplings between frontal regions and amygdala sub-regions are involved in different spontaneous emotion regulation processes by using an individual-difference approach and a generalized psycho-physiological interaction (gPPI) approach. Specifically, 50 healthy participants reported their dispositional use of spontaneous cognitive reappraisal and expressive suppression in daily life and their actual use of these two strategies during the performance of an emotional-picture watching task. Results showed that functional coupling between the orbitofrontal cortex (OFC) and the basolateral amygdala (BLA) was associated with higher scores of both dispositional and actual uses of reappraisal. Similarly, functional coupling between the dorsolateral prefrontal cortex (dlPFC) and the centromedial amygdala (CMA) was associated with higher scores of both dispositional and actual uses of suppression. Mediation analyses indicated that functional coupling of the right OFC-BLA partially mediated the association between reappraisal and emotional response, irrespective of whether reappraisal was measured by dispositional use (indirect effect(SE)=-0.2021 (0.0811), 95%CI(BC)= [-0.3851, -0.0655]) or actual use (indirect effect(SE)=-0.1951 (0.0796), 95%CI(BC)= [-0.3654, -0.0518])). These findings suggest that spontaneous reappraisal and suppression involve distinct frontal- amygdala functional couplings, and the modulation of BLA activity from OFC may be necessary for changing emotional response during spontaneous reappraisal.