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This study employs synthetic jet actuation (SJA) to control large-scale flow separation on the suction side of a NACA0015 aerofoil at a Reynolds number of 2.1 $\times$$10^5$ and an angle of $18^\circ$. The underlying control mechanism is investigated using large-eddy simulations to resolve the dynamics of jet-induced coherent structures associated with the low-frequency actuation. During the periodic blowing and suction cycle, two distinct types of spanwise coherent vortices are identified: blowing-induced vortices (BIVs) and suction-induced vortices (SIVs), which differ significantly in spatial distribution and energy content. As these vortices are convected downstream at speeds comparable to the free-stream velocity, BIVs exhibit a significantly slower rate of energy decay, whereas SIVs dissipate rapidly, particularly near the trailing edge. Triple decomposition analysis shows that energy addition is primarily associated with the coherent velocity components. Notably, BIVs exhibit a stronger entrainment capacity, enhancing momentum exchange between the separated shear layer and outer flow via coherent Reynolds shear stresses. This intensified exchange facilitates the outward transport of low-momentum fluid, effectively enhancing aerodynamic performance and delaying flow separation. Furthermore, spectral proper orthogonal decomposition reveals distinct energy peaks centred at the actuation frequency and its harmonics. Among the two vortex types, BIVs contribute most of the coherent spectral energy, highlighting their critical role in the overall effectiveness of the flow control. These findings elucidate the flow organisation and modulation mechanisms associated with low-frequency SJA under deep-stall conditions, and provide a physical interpretation of the observed reorganisation of the separated flow.
Replacing soiled bed linens is a common practice in intensive care units . We identified dust-driven transmission of carbapenem-resistant Acinetobacter baumannii correlated with changing bed linens by air sampling and genome-based analysis. This uncovers a hidden airborne route, which needs to be considered to design countermeasures against multidrug-resistant organisms.
The mechanisms governing generation and amplification of laser-driven electromagnetic pulses (EMPs) in the picosecond (ps) regime remain insufficiently understood. Here, we present a unified theoretical and experimental framework that demonstrates dual-picosecond laser irradiation of solid targets can synergistically enhance EMP emission. By integrating particle-in-cell simulations with three-dimensional electromagnetic modeling, we reveal that the increasing laser focal power density amplifies hot electron emission and strengthens neutralization currents, leading to giant EMP radiations. Experimentally, we validate these predictions at the XG-III and SG-II U picosecond petawatt laser facilities, achieving a record-breaking EMP field strength of 3.08 MV/m – substantially exceeding previously reported values from ps-laser–solid interactions. Furthermore, we demonstrate that EMP characteristics can be precisely tuned via laser and target parameters, enabling controllable, high-field electromagnetic sources. Our findings provide deep insight into the physics of laser-driven EMP amplification and establish a robust platform for developing next-generation high-intensity electromagnetic emitters.
Since little is known about the mental health status of Chinese male adults, the present study aimed to explore the prevalence and predictors of psychological distress among Chinese male adults. This cross-sectional study recruited 6,140 men by convenience sampling in Liaoning and Shanghai. Psychological distress and perceived social support were measured by the Depression, Anxiety, and Stress Scale-21 and the Perceived Social Support Scale. Multivariable logistic regression analysis was employed to investigate the factors associated with psychological distress. The prevalence of depression, anxiety and stress among Chinese male adults were 14.2%, 26.4% and 12.9%, respectively. Male adults with low perceived social support reported symptoms on all measurements. Being middle-aged, college or above and residing in urban areas were associated with depression, while living in urban areas was the independent risk factor of anxiety. Stress was significantly associated with being middle-aged, married status and college or above. Our results revealed a high prevalence of psychological distress among Chinese male adults in this sample. Results suggest more attention needs to be paid to the mental health of male adults in the studied population, especially those who are middle-aged, college or above, married status and reside in urban areas.
Depressive symptoms are closely associated with cognitive decline and risk of incident dementia, and plasma biomarkers may play a significant role in this relationship. We aimed to investigate the influence of plasma biomarkers and explore the underlying mechanisms.
Methods
This study included 1,658 dementia-free community residents recruited in 2009–2011 from the Shanghai Aging Study. At baseline, we assayed plasma phosphorylated tau 217 (p-tau217) and neurofilament light chain (NfL), and assessed depressive symptoms using the Center for Epidemiologic Studies Depression scale. Cox regression models were performed to estimate the risks of incident dementia and Alzheimer’s disease (AD) during the 5-year follow-up. Parallel and serial mediation models were applied to investigate whether plasma p-tau217 and NfL mediated the relationship between depressive symptoms and cognitive decline.
Results
Older adults with depressive symptoms had higher risks of dementia and AD, especially among those with higher concentrations of baseline plasma p-tau217/NfL. Sex-specific analysis revealed that depressive symptoms combined with high plasma NfL increased AD risk in men (hazard ratio, HR [95% confidence interval, CI] = 5.89 [2.01, 17.27], p = 0.001), whereas women with depressive symptoms and high plasma p-tau217 showed higher AD risk (HR [95%CI] = 6.07 [2.82, 13.09], p < 0.001). Parallel mediation analysis revealed that plasma p-tau217/NfL mediated the relationship between depressive symptoms and cognitive decline, respectively. Additionally, serial mediation analysis found p-tau217 precedes NfL within the mediating pathway (β = 0.403, bootstrap 95% CI: 0.347, 0.452).
Conclusions
Plasma p-tau217 and NfL could individually or jointly mediate the relationship between depressive symptoms and cognitive decline.
How psychotic symptoms, depressive symptoms, cognitive deficits, and functional impairment may interact with one another in schizophrenia or bipolar disorder is unclear.
Methods
This study explored these interactions in a discovery sample of 339 Chinese, of whom 146 had first-episode schizophrenia and 193 had bipolar disorder. Psychotic symptoms were assessed using the Positive and Negative Symptom Scale; depressive symptoms, using the Hamilton Depression Rating Scale; cognitive deficits, using tests of processing speed, executive function, and logical memory; and functional impairment, using clinical assessments. Network models connecting the four types of variables were developed and compared between men and women and between disorders. Potential causal relationships among the variables were explored through directed acyclic graphing. The results in the discovery sample were compared to those obtained for a validation sample of 235 Chinese, of whom 138 had chronic schizophrenia and 97 had bipolar disorder.
Results
In the discovery and validation cohorts, schizophrenia and bipolar disorder showed similar networks of associations, in which the central hubs included ‘disorganized’ symptoms, depressive symptoms, and deficits in processing speed during the digital symbol substitution test. Directed acyclic graphing suggested that disorganized symptoms were upstream drivers of cognitive impairment and functional decline, while core depressive symptoms (e.g. low mood) drove somatic and anxiety symptoms.
Conclusions
Our study advocates for transdiagnostic, network-informed strategies prioritizing the mitigation of disorganization and depressive symptoms to disrupt symptom cascades and improve functional outcomes in schizophrenia and bipolar disorder.
In this paper, we prove the existence of minimizers for the sharp stability constant of Caffarelli–Kohn–Nirenberg inequality near the new curve $b^*_{\mathrm{FS}}(a)$ (which lies above the well-known Felli–Schneider curve $b_{\mathrm{FS}}(a)$), extending the work of Wei and Wu [Math. Z., 2024] to a slightly larger region. Moreover, we provide an upper bound for the Caffarelli–Kohn–Nirenberg inequality with an explicit sharp constant, which may have its own interest.
MicroRNAs (miRNAs) alterations in patients with bipolar disorder (BD) are pivotal to the disease’s pathogenesis. Since obtaining brain tissue is challenging, most research has shifted to analyzing miRNAs in peripheral blood. One innovative solution is sequencing miRNAs in plasma extracellular vesicles (EVs), particularly those neural-derived EVs emanating from the brain.
Methods
We isolated plasma neural-derived EVs from 85 patients with BD and 39 healthy controls (HC) using biotinylated antibodies targeting a neural tissue marker, followed by miRNA sequencing and expression analysis. Furthermore, we conducted bioinformatic analyses and functional experiments to delve deeper into the underlying pathological mechanisms of BD.
Results
Out of the 2,656 neural-derived miRNAs in EVs identified, 14 were differentially expressed between BD patients and HC. Moreover, the target genes of miR-143-3p displayed distinct expression patterns in the prefrontal cortex of BD patients versus HC, as sourced from the PsychENCODE database. The functional experiments demonstrated that the abnormal expression of miR-143-3p promoted the proliferation and activation of microglia and upregulated the expression of proinflammatory factors, including IL-1β, IL-6, and NLRP3. Through weighted gene co-expression network analysis, a module linking to the clinical symptoms of BD patients was discerned. Enrichment analyses unveiled these miRNAs’ role in modulating the axon guidance, the Ras signaling pathway, and ErbB signaling pathway.
Conclusions
Our findings provide the first evidence of dysregulated plasma miRNAs within neural-derived EVs in BD patients and suggest that neural-derived EVs might be involved in the pathophysiology of BD through related biological pathways, such as neurogenesis and neuroinflammation.
To explore the treatment options and prognostic factors of vocal fold leukoplakia.
Methods
The study examined conservative and surgical treatment approaches, and analysed prognostic factors influencing vocal fold leukoplakia outcomes.
Results
In the conservative treatment group, lesion size (p = 0.035) and smoking (p < 0.001) were identified as independent factors influencing treatment outcomes. In the surgical treatment group, lesion size (p = 0.018) was identified as an independent factor affecting recurrence. There was no statistically significant difference in the effectiveness of conservative versus surgical treatment for patients with hyperplasia (p = 0.223), mild dysplasia (p = 0.634) and moderate dysplasia (p = 0.758).
Conclusion
Smoking and lesion size are key factors influencing the outcome of conservative treatment, while lesion size is a significant factor affecting recurrence in surgically treated patients. More importantly, conservative treatment should be prioritised for patients with moderate dysplasia and milder vocal fold leukoplakia.
To define extended high-frequency hearing threshold ranges in normal hearing elderly (aged 55 years and above) and identify associated risk factors for extended high-frequency hearing loss.
Methods
Pure-tone thresholds (0.25–16 kHz) and word recognition scores were measured using portable audiometric equipment. Lifestyle and medical histories were collected, and generalised linear models analysed risk factors for extended high-frequency hearing (10–12 kHz).
Results
In normal hearing elderly (28 ears, 18 subjects), 95 per cent confidence intervals for 10 and 12 kHz were 34.770–49.301 and 56.976–65.809, respectively. Among 342 ears (200 subjects), hypertension emerged as a leading risk factor for extended high-frequency hearing loss, while lipid-lowering medications showed potential protective effects.
Conclusion
Preliminary extended high-frequency hearing thresholds were established, with hypertension identified as a key risk factor and lipid-lowering medications as a potential protective factor.
The betatron radiation source features a micrometer-scale source size, a femtosecond-scale pulse duration, milliradian-level divergence angles and a broad spectrum exceeding tens of keV. It is conducive to the high-contrast imaging of minute structures and for investigating interdisciplinary ultrafast processes. In this study, we present a betatron X-ray source derived from a high-charge, high-energy electron beam through a laser wakefield accelerator driven by the 1 PW/0.1 Hz laser system at the Shanghai Superintense Ultrafast Laser Facility (SULF). The critical energy of the betatron X-ray source is 22 ± 5 keV. The maximum X-ray flux reaches up to 4 × 109 photons for each shot in the spectral range of 5–30 keV. Correspondingly, the experiment demonstrates a peak brightness of 1.0 × 1023 photons·s−1·mm−2·mrad−2·0.1%BW−1, comparable to those demonstrated by third-generation synchrotron light sources. In addition, the imaging capability of the betatron X-ray source is validated. This study lays the foundation for future imaging applications.
Post-traumatic stress disorder (PTSD) is a mental health condition caused by the dysregulation or overgeneralization of memories related to traumatic events. Investigating the interplay between explicit narrative and implicit emotional memory contributes to a better understanding of the mechanisms underlying PTSD.
Methods
This case–control study focused on two groups: unmedicated patients with PTSD and a trauma-exposed control (TEC) group who did not develop PTSD. Experiments included real-time measurements of blood oxygenation changes using functional near-infrared spectroscopy during trauma narration and processing of emotional and linguistic data through natural language processing (NLP).
Results
Real-time fNIRS monitoring showed that PTSD patients (mean [SD] Oxy-Hb activation, 0.153 [0.084], 95% CI 0.124 to 0.182) had significantly higher brain activity in the left anterior medial prefrontal cortex (L-amPFC) within 10 s after expressing negative emotional words compared with the control group (0.047 [0.026], 95% CI 0.038 to 0.056; p < 0.001). In the control group, there was a significant time-series correlation between the use of negative emotional memory words and activation of the L-amPFC (latency 3.82 s, slope = 0.0067, peak value = 0.184, difference = 0.273; Spearman’s r = 0.727, p < 0.001). In contrast, the left anterior cingulate prefrontal cortex of PTSD patients remained in a state of high activation (peak value = 0.153, difference = 0.084) with no apparent latency period.
Conclusions
PTSD patients display overactivity in pathways associated with rapid emotional responses and diminished regulation in cognitive processing areas. Interventions targeting these pathways may alleviate symptoms of PTSD.
Microstates of an electroencephalogram (EEG) are canonical voltage topographies that remain quasi-stable for 90 ms, serving as the foundational elements of brain dynamics. Different changes in EEG microstates can be observed in psychiatric disorders like schizophrenia (SCZ), major depressive disorder (MDD), and bipolar disorder (BD). However, the similarities and disparatenesses in whole-brain dynamics on a subsecond timescale among individuals diagnosed with SCZ, BD, and MDD are unclear.
Methods
This study included 1112 participants (380 individuals diagnosed with SCZ, 330 with BD, 212 with MDD, and 190 demographically matched healthy controls [HCs]). We assembled resting-state EEG data and completed a microstate analysis of all participants using a cross-sectional design.
Results
Our research indicates that SCZ, BD, and MDD exhibit distinct patterns of transition among the four EEG microstate states (A, B, C, and D). The analysis of transition probabilities showed a higher frequency of switching from microstates A to B and from B to A in each patient group compared to the HC group, and less frequent transitions from microstates A to C and from C to A in the SCZ and MDD groups compared to the HC group. And the probability of the microstate switching from C to D and D to C in the SCZ group significantly increased compared to those in the patient and HC groups.
Conclusions
Our findings provide crucial insights into the abnormalities involved in distributing neural assets and enabling proper transitions between different microstates in patients with major psychiatric disorders.
Digitaria ciliaris var. chrysoblephara (Fig. & De Not.) R.R. Stewart is an annual xeromorphic weed that severely infests direct-seeded rice fields in China. Herbicide resistance is emerging in D. ciliaris var. chrysoblephara owing to extensive and recurrent use of the acetyl-CoA carboxylase (ACCase)-inhibiting herbicide metamifop. In this study, a total of 53 D. ciliaris var. chrysoblephara populations randomly sampled from direct-seeded rice fields across Jiangsu Province were investigated for metamifop resistance and potential resistance-endowing mutations. Single-dose assays revealed that 17 (32.1%) populations evolved resistance to metamifop and 5 (9.4%) populations were in the process of developing resistance. The resistance index (RI) of metamifop-resistant populations ranged from 2.7 to 32.1. Amino acid substitutions (Ile-1781-Leu, Trp-2027-Cys/Ser, and Ile-2041-Asn) in ACCase genes were detected in resistant D. ciliaris var. chrysoblephara plants and caused various cross-resistance patterns to ACCase-inhibiting herbicides. All of four resistant populations (YC07, YZ09, SQ03, and HA06), with different ACCase mutations, exhibited cross-resistance to the aryloxyphenoxypropionate (APP) herbicides cyhalofop-butyl (RI values: 10.0 to 19.9), fenoxaprop-P-ethyl (RI values: 53.7 to 132.8), and haloxyfop-P-methyl (RI values: 6.2 to 62.6), and the phenylpyrazoline (DEN) pinoxaden (RI values: 2.3 to 5.4), but responded differently to the cyclohexanedione (CHD) herbicides clethodim and sethoxydim. It is noteworthy that four postemergence herbicides used for rice cropping, including bispyribac-sodium, pyraclonil, quinclorac, and anilofos, showed poor control effect against D. ciliaris var. chrysoblephara, suggesting few alternations for managing this weed in rice fields except ACCase inhibitors. In conclusion, this work demonstrated that the D. ciliaris var. chrysoblephara had developed resistance to ACCase-inhibiting herbicides in rice cultivation of China, and target-site amino acid substitutions in ACCase were primarily responsible for metamifop resistance.
Chinese nurses working with immense stress may have issues with burnout during COVID-19 regular prevention and control. There were a few studies investigating status of burnout and associated factors among Chinese nurses. However, the relationships remained unclear.
Objectives
To investigate status and associated factors of nurses’ burnout during COVID-19 regular prevention and control.
Methods
784 nurses completed questionnaires including demographics, Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, Insomnia Severity Index, Impact of Event Scale-revised, Perceived Social Support Scale, Connor–Davidson Resilience Scale, General Self-efficacy Scale and Maslach Burnout Inventory.
Results
310 (39.5%), 393 (50.1%) and 576 (73.5%) of respondents were at high risk of emotional exhaustion (EE), depersonalization (DP) and reduced personal accomplishment (PA). The risk of EE, DP and reduced PA were moderate, high and high. Nurses with intermediate and senior professional rank and title and worked >40 h every week had lower scores in EE. Those worked in low-risk department reported lower scores in PA. Anxiety, post-traumatic stress disorder (PTSD), self-efficacy and social support were influencing factors of EE and DP, while social support and resilience were associated factors of PA.
Conclusion
Chinese nurses’ burnout during COVID-19 regular prevention and control was serious. Professional rank and title, working unit, weekly working hours, anxiety, PTSD, self-efficacy, social support and resilience were associated factors of burnout.
Although dopaminergic disturbances are well-known in schizophrenia, the understanding of dopamine-related brain dynamics remains limited. This study investigates the dynamic coactivation patterns (CAPs) associated with the substantia nigra (SN), a key dopaminergic nucleus, in first-episode treatment-naïve patients with schizophrenia (FES).
Methods
Resting-state fMRI data were collected from 84 FES and 94 healthy controls (HCs). Frame-wise clustering was implemented to generate CAPs related to SN activation or deactivation. Connectome features of each CAP were derived using an edge-centric method. The occurrence for each CAP and the balance ratio for antagonistic CAPs were calculated and compared between two groups, and correlations between temporal dynamic metrics and symptom burdens were explored.
Results
Functional reconfigurations in CAPs exhibited significant differences between the activation and deactivation states of SN. During SN activation, FES more frequently recruited a CAP characterized by activated default network, language network, control network, and the caudate, compared to HCs (F = 8.54, FDR-p = 0.030). Moreover, FES displayed a tilted balance towards a CAP featuring SN-coactivation with the control network, caudate, and thalamus, as opposed to its antagonistic CAP (F = 7.48, FDR-p = 0.030). During SN deactivation, FES exhibited increased recruitment of a CAP with activated visual and dorsal attention networks but decreased recruitment of its opposing CAP (F = 6.58, FDR-p = 0.034).
Conclusion
Our results suggest that neuroregulatory dysfunction in dopaminergic pathways involving SN potentially mediates aberrant time-varying functional reorganizations in schizophrenia. This finding enriches the dopamine hypothesis of schizophrenia from the perspective of brain dynamics.