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The successful colonization of invasive plants (IPs) may be facilitated by their nutrient release during decomposition, which alters soil physicochemical properties, enzyme activities, microbial metabolic processes and the diversity of soil microorganisms. This study aimed to examine the effects of co-decomposition of four Asteraceae IPs (Conyza canadensis, Conyza sumatrensis, Erigeron annuus and Solidago canadensis) along a gradient of invasion and a native plant (Pterocypsela laciniata) on decomposition rate, soil physicochemical properties, soil enzyme activities and the diversity of soil bacterial communities (SBCs). Leaves of C. canadensis with heavy invasion and S. canadensis with light and heavy invasion decomposed more slowly than P. laciniata. Leaves of C. canadensis with full invasion decomposed more rapidly than P. laciniata. Pterocypsela laciniata and C. sumatrensis had synergistic effects on each other’s decomposition, whereas P. laciniata and S. canadensis displayed an antagonistic effect. Decomposition of the four IPs increased soil microbial carbon content but reduced soil fluorescein diacetate (FDA) hydrolase activity compared to P. laciniata. Thus, invasion degree and species identity of IPs modulate the effects of the four IPs on the decomposition rate, mixed-effect intensity of co-decomposition, soil microbial carbon content, soil FDA hydrolase activity and SBC structure.
Large-scale field investigation in the Eastern Tianshan Mountains of Xinjiang identified 108 Palaeolithic/microlithic surface findspots. Pulei Cave reveals the first well-preserved spelean sediment record containing Upper Palaeolithic cultural remains in eastern Xinjiang, dating from c. 45–43 ka BP.
Patients with posttraumatic stress disorder (PTSD) exhibit smaller regional brain volumes in commonly reported regions including the amygdala and hippocampus, regions associated with fear and memory processing. In the current study, we have conducted a voxel-based morphometry (VBM) meta-analysis using whole-brain statistical maps with neuroimaging data from the ENIGMA-PGC PTSD working group.
Methods
T1-weighted structural neuroimaging scans from 36 cohorts (PTSD n = 1309; controls n = 2198) were processed using a standardized VBM pipeline (ENIGMA-VBM tool). We meta-analyzed the resulting statistical maps for voxel-wise differences in gray matter (GM) and white matter (WM) volumes between PTSD patients and controls, performed subgroup analyses considering the trauma exposure of the controls, and examined associations between regional brain volumes and clinical variables including PTSD (CAPS-4/5, PCL-5) and depression severity (BDI-II, PHQ-9).
Results
PTSD patients exhibited smaller GM volumes across the frontal and temporal lobes, and cerebellum, with the most significant effect in the left cerebellum (Hedges’ g = 0.22, pcorrected = .001), and smaller cerebellar WM volume (peak Hedges’ g = 0.14, pcorrected = .008). We observed similar regional differences when comparing patients to trauma-exposed controls, suggesting these structural abnormalities may be specific to PTSD. Regression analyses revealed PTSD severity was negatively associated with GM volumes within the cerebellum (pcorrected = .003), while depression severity was negatively associated with GM volumes within the cerebellum and superior frontal gyrus in patients (pcorrected = .001).
Conclusions
PTSD patients exhibited widespread, regional differences in brain volumes where greater regional deficits appeared to reflect more severe symptoms. Our findings add to the growing literature implicating the cerebellum in PTSD psychopathology.
Glyphosate, the most prevalent pesticide and widely used herbicide globally, has seen much research on its potential ecological toxicity. Glyphosate-based herbicide (GBH) is directly sprayed in the field, exposing predators to the chemical through contaminated prey or direct contact. While the consequences of ingesting glyphosate have been explored, the specific impact of GBH spraying on Chrysopa pallens (Neuroptera: Chrysopidae) remains unclear. In this study, life tables were constructed to evaluate the potential effects of different stages of exposure to GBH on both the parents (F0) and offspring (F1) of C. pallens, and the expression of genes related to the insulin signalling pathway and vitellogenin (Vg1) was detected by reverse transcription-quantitative polymerase chain reaction. The results revealed that medium (10 mL/L) and high (20 mL/L) concentrations of GBH adversely affected the development and longevity of the F0 and F1 generation of C. pallens larvae. Notably, high concentrations of GBH significantly reduced the fecundity of the F0 and suppressed Vg1 transcription at both medium and high concentrations. While GBH treatment of C. pallens adults showed no harmful effects on the longevity, fecundity, population parameters, and the transcription levels of genes involved in insulin signalling and Vg1 in the F0. Nevertheless, it altered the developmental duration of the F1. Therefore, spraying GBH may lead to reduced fecundity and inhibit the Vg1 transcription, posing potential risks to both parental and offspring generations of C. pallens. These findings offer valuable insights into the proper utilisation of GBH.
High-power lasers are vital for particle acceleration, imaging, fusion and materials processing, requiring precise control and high-energy delivery. Laser plasma accelerators (LPAs) demand laser positional stability at focus to ensure consistent electron beams in applications such as X-ray free-electron lasers and high-energy colliders. Achieving this stability is especially challenging for the low-repetition-rate lasers in current LPAs. We present a machine learning method that predicts and corrects laser pointing instabilities in real-time using a high-frequency pilot beam. By preemptively adjusting a correction mirror, this approach overcomes traditional feedback limits. Demonstrated on the BELLA petawatt laser operating at the terawatt level (30 mJ amplification), our method achieved root mean square pointing stabilization of 0.34 and 0.59 $\unicode{x3bc} \mathrm{rad}$ in the x and y directions, reducing jitter by 65% and 47%, respectively. This is the first successful application of predictive control for shot-to-shot stabilization in low-repetition-rate laser systems, paving the way for full-energy petawatt lasers and transformative advances across science, industry and security.
Spatial intensity modulation in amplified laser beams, particularly hot spots, critically constrains attainable pulse peak power due to the damage threshold limitations of four-grating compressors. This study demonstrates that the double-smoothing grating compressor (DSGC) configuration effectively suppresses modulation through directional beam smoothing. Our systematic investigation validated the double-smoothing effect through numerical simulations and experimental measurements, with comprehensive spatiotemporal analysis revealing excellent agreement between numerical and practical pulse characteristics. Crucially, the DSGC enables a 1.74 times energy output boost compared to conventional compressors. These findings establish the DSGC as a pivotal advancement for next-generation ultrahigh-power laser systems, providing a viable pathway toward hundreds of PW output through optimized spatial energy redistribution.
Adolescence marks a critical transition period, with significant mental health challenges including anxiety and depression symptoms that affect long-term happiness. There has been a lack of research exploring the factors mediating adolescent happiness.
Aims
To investigate the mediating effects of anxiety and depression on adolescent happiness, as well as the contributions of sociodemographic factors.
Methods
We recruited 392 adolescents. Anxiety symptoms, depression symptoms and happiness were assessed by the seven-item Generalized Anxiety Disorder scale, nine-item Patient Health Questionnaire and single-item happiness scale, respectively. Self-administered questionnaires were used to collect sociodemographic information.
Results
Spearman correlation analysis showed significant negative correlations of happiness with anxiety (r = −0.37, P < 0.0001) and depression (r = −0.47, P < 0.0001). Positive predictors of happiness included quality of parents’ marriage (β = 0.12, P = 0.006), regular physical exercise (β = 0.13, P = 0.006) and regular diet (β = 0.10, P = 0.03). Mediation analysis indicated that depressive symptoms (estimate = 0.50, 95% CI: 0.25 to 0.80) and anxiety symptoms (estimate = 0.32, 95% CI: 0.12 to 0.57) partially mediated the relationship between regular exercise and happiness, whereas depressive symptoms completely mediated the relationship between anxiety symptoms and happiness (estimate = −0.14, 95% CI: −0.20 to −0.08).
Conclusion
The findings of this study highlight the intricate interplay of mental health issues, lifestyle factors and adolescent happiness and emphasise the need for comprehensive interventions focusing on enhancing physical activity and addressing psychological health to foster happiness among adolescents.
The purpose of this study was to measure and examine the levels of IgG, IgM, and Spike antibody induced by inactivated vaccines, including CoronaVac and BBIBP-CorV.
Methods
Two groups of healthy adults over 18 years old (50 participants per group), who had previously received 1 dose of either BBIBP-CorV or CoronaVac and receiving either a homologous booster of BBIBP-CorV or a heterologous booster of CoronaVac. Serum IgG, IgM, and Spike antibody levels against SARS-COV-2 were measured using magnetic particle chemiluminescence immunoassay and the ELISA method.
Results
The results showed that both spike antibody and IgG/IgM antibodies elicited by a CoronaVac booster following 1 dose of BBIBP-CorV were significantly higher than those elicited by either a homologous BBIBP-CorV booster or a heterologous BBIBP-CorV booster. The Spike antibody against SARS-COV-2 induced by the heterologous CoronaVac booster reached 200.3, which is substantially greater than that induced by the homologous BBIBP-CorV booster (127.5 pg/mL). Conversely, the Spike antibody against SARS-COV-2 induced by the heterologous BBIBP-CorV booster reached 53.93 pg/mL, which is substantially greater than that induced by the homologous CoronaVac booster (9.60 pg/mL).
Conclusions
In summary, CoronaVac is immunogenic as a booster dose following 1 dose of BBIBP-CorV and is immunogenically superior to both the homologous booster and the heterologous BBIBP-CorV booster.
This paper proposes a compact coplanar waveguide-fed slot antenna for ultra-wideband wearable applications, featuring six notch bands. The antenna utilizes a flexible liquid crystal polymer substrate with a thickness of 0.1 mm. The antenna achieves six band-notched characteristics by incorporating a split concentric ring etched on the radiating patch and L-shaped branches loaded on the ground plane. The proposed flexible antenna has dimensions of 30 × 30 mm2(0.65λ0*0.65λ0,λ0 is the free space wavelength at 6.5 GHz.). Measurement results show an impedance bandwidth ranging from 2.37 to 13.7 GHz and a fractional bandwidth of 134%. The notch bands cover 2.9–3.77 GHz for WiMAX applications, 4.14–4.9 GHz for the ARN band, 5.09–5.55 GHz for the WLAN downlink band, 5.86–6.46 GHz for the C-band uplink band, 6.66–7.39 GHz for the C-band/INSAT/super-extended band, and 7.93–8.43 GHz for ITU-8 GHz. The maximum gain in the operating band is 6.5 dBi. The performances of the flexible antenna are analyzed under bending conditions. The ANSYS HFSS electromagnetic simulator was used for the design and simulation of the proposed antenna. The flexible antenna is suitable for wearable applications.
A four-port ultra-wideband (UWB) multiple-input multiple-output (MIMO) antenna with three notch bands is proposed in this work. The antenna uses ultra-thin flexible material liquid crystal polymer (LCP) as the substrate. Four identical monopole radiators are designed in this proposed antenna system. The notch bands of the antenna are generated by adding complementary split ring resonator (CSRR) and ring branch. A cross-shaped stub is set in the center of the four antenna units to enhance the isolation. The measured bandwidth of the antenna is 2.54–10.69 GHz, filtering out three notch frequency bands of 2.81–3.85, 5.11–5.98, and 7.34–8.69 GHz. The isolation in the entire working frequency is better than 22 dB. The bent performances of the MIMO system and the specific absorption rate (SAR) value are analyzed. The low SAR values, low envelope correlation coefficient (<0.05), high diversity gain (>9.999), and stable gain of the proposed antenna indicate that in UWB-MIMO systems and wearable Internet of Things applications, it can be widely used.
Despite global efforts to end tuberculosis (TB), the goal of preventing catastrophic health expenditure (CHE) due to TB remains unmet. This cross-sectional study was conducted in Guizhou Province, Southwest China. Data were collected from the Hospital Information System and a survey of TB patients who had completed standardized antituberculosis treatment between January and March 2021. Among the 2 283 participants, the average total expenditure and out-of-pocket expenditure were $1 506.6 (median = $760.5) and $683.6 (median = $437.8), respectively. Health insurance reimbursement reduced CHE by 16.8%, with a contribution rate of 24.9%, and the concentration index changed from -0.070 prereimbursement to -0.099 postreimbursement. However, the contribution of health insurance varied significantly across different economic strata, with contribution rates of 6.4% for the lowest economic group and 53.1% for the highest group. For patients from lower socioeconomic strata, health insurance contributed 10.7% to CHE in the prediagnostic phase and 23.5% during treatment. While social health insurance alleviated the financial burden for TB patients, it did not provide sufficient protection for those in lower economic strata or during the prediagnostic stage. This study underscores the need for more effective and equitable subsidy policies for TB patients .
This study aims to evaluate the impact of low-carbohydrate diet, balanced dietary guidance and pharmacotherapy on weight loss among individuals with overweight or obesity over a period of 3 months. The study involves 339 individuals with overweight or obesity and received weight loss treatment at the Department of Clinical Nutrition at the Second Affiliated Hospital of Zhejiang University, School of Medicine, between 1 January 2020 and 31 December 2023. The primary outcome is the percentage weight loss. Among the studied patients, the majority chose low-carbohydrate diet as their primary treatment (168 (49·56 %)), followed by balanced dietary guidance (139 (41·00 %)) and pharmacotherapy (32 (9·44 %)). The total percentage weight loss for patients who were followed up for 1 month, 2 months and 3 months was 4·98 (3·04, 6·29) %, 7·93 (5·42, 7·93) % and 10·71 (7·74, 13·83) %, respectively. Multivariable logistic regression analysis identified low-carbohydrate diet as an independent factor associated with percentage weight loss of ≥ 3 % and ≥ 5 % at 1 month (OR = 0·461, P < 0·05; OR = 0·349, P < 0·001). The results showed that a low-carbohydrate diet was an effective weight loss strategy in the short term. However, its long-term effects were comparable to those observed with balanced dietary guidance and pharmacotherapy.
The AIMTB rapid test assay is an emerging test, which adopted a fluorescence immunochromatographic assay to measure interferon-γ (IFN-γ) production following stimulation of effector memory T cells in whole blood by mycobacterial proteins. The aim of this article was to explore the ability of AIMTB rapid test assay in detecting Mycobacterium tuberculosis (MTB) infection compared with the widely applied QuantiFERON-TB Gold Plus (QFT-Plus) test among rural doctors in China. In total, 511 participants were included in the survey. The concordance between the QFT-Plus test and the AIMTB rapid test assay was 94.47% with a Cohen’s kappa coefficient (κ) of 0.84 (95% CI, 0.79–0.90). Improved concordance between the two tests was observed in males and in participants with 26 or more years of service as rural doctors. The quantitative values of the QFT-Plus test was higher in individuals with a result of QFT-Plus-/AIMTB+ as compared to those with a result of QFT-Plus-/AIMTB- (p < 0.001). Overall, our study found that there was an excellent consistency between the AIMTB rapid test assay and the QFT-Plus test in a Chinese population. As the AIMTB rapid test assay is fast and easy to operate, it has the potential to improve latent tuberculosis infection testing and treatment at the community level in resource-limited settings.
Continuum robots offer unique advantages in performing tasks within extremely confined environments due to their exceptional dexterity and adaptability. However, their soft materials and elastic structures inherently introduce nonlinearity and shape instability, especially when the robot encounters external contact forces. To address these challenges, this paper presents a comprehensive model and experimental study to estimate the shape deformation of a switchable rigid-continuum robot (SRC-Bot). The kinematic analysis is first conducted to specify the degrees of freedom (DoF) and basic motions of SRC-Bot, including motion of bending, rotating, and elongating. This analysis assumes that the curvature varies along the central axis and maps the relationship between joint space and driven space. Subsequently, an equivalence concept is proposed to unify the stiffness addressing each DoF, which is then utilized in the establishment of the dynamic model. According to the mechanical structural design, the deformed posture of SRC-Bot is discretized into five segments, corresponding to the distribution of the guiders. The dynamics model is then derived using Newton’s second law and Euler’s method to simulate the deformation under gravity, friction, and external forces. Additionally, the stiffness in three directions is quantified through an identification process to complete the theoretical model. Furthermore, a series of experiments are conducted and compared with simulated results to validate the response and deformed behavior of SRC-Bot. The comparative results demonstrate that the proposed model-based simulation accurately captures the deformable characteristics of the robot, encompassing both static deformed postures and dynamic time-domain responses induced by external and actuation forces.
Revealing the impact of forest succession processes on changes in plant diversity is crucial for understanding the mechanisms that maintain plant diversity across various succession stages. While previous research has predominantly focused on the influence of environmental factors or management strategies on plant diversity within rubber plantation understories, there is a scarcity of studies examining the effects of forest succession processes on plant diversity. This study focuses on the plant diversity of the understory herbaceous layer within the rubber forest of the Yinggeling area, located in National Park of Hainan Tropical Rainforest. It employs a spatial analysis approach, rather than a temporal one, to examine the characteristics of the understory herbaceous community. The findings revealed that (1) The understory of Yinggeling rubber plantations harbors 175 plant species from 149 genera and 75 families, with Gramineae and Rubiaceae representing 46.45% of total species. And the dominant families are Rubiaceae, Gramineae, and Moraceae, with Ficus and Pteris being the dominant genera. (2) The dominant species vary with succession duration, with Tetrastigma pachyphyllum dominating in 0-year succession, Paspalum conjugatum in 3-year succession, and Microstegium fasciculatum in 7-year succession. (3) Diversity indices such as the Shannon–Wiener index, Simpson index, and Pielou index peak at 7 years of natural succession, while the species richness is highest at 3 years. (4) The similarity coefficient between understory herbaceous plant communities in rubber plantations undergoing 0 and 3 years of natural succession is highest 0.56, indicating a significant similarity, while similarity is lowest between 0 and 7 years of succession. This research shows that natural restoration helps increase species diversity in the understory herb layer of rubber forests. Succession leads to changes in the dominant families, genera, and species of the herbaceous layer. This change can be attributed to the intraspecific competition and ecological competition that occur during the succession process, leading to changes in biological and resource allocation.
Newborn calf diarrhea has led to widespread overuse of antibiotics. Therefore, it is crucial to find effective solutions for calf diarrhea. In this study, we aimed to evaluate the impact of the synthetic organic zinc-chelating-peptide glycine-glutamine-Zn (GQ-Zn) on the microbiota and metabolites in the gut of calves with diarrhea. The results showed that GQ-Zn alleviated diarrhea in calves. Additionally, 16S rDNA sequencing and metabolomic analysis revealed that GQ-Zn improved antioxidant capacity, relieved inflammation, altered the gut microbiota by decreasing the number of harmful bacteria Prevotella denticola, Fusobacterium necrophorum and influenced metabolomic profiles via the linoleic acid metabolic pathway in calves. In conclusion, GQ-Zn supplementation alleviated diarrhea through regulating the gut microbiota and metabolites in pre-weaning Holstein calves.
The discovery that blazars dominate the extra-galactic $\gamma$-ray sky is a triumph in the Fermi era. However, the exact location of $\gamma$-ray emission region still remains in debate. Low-synchrotron-peaked blazars (LSPs) are estimated to produce high-energy radiation through the external Compton process, thus their emission regions are closely related to the external photon fields. We employed the seed factor approach proposed by Georganopoulos et al. It directly matches the observed seed factor of each LSP with the characteristic seed factors of external photon fields to locate the $\gamma$-ray emission region. A sample of 1 138 LSPs with peak frequencies and peak luminosities was adopted to plot a histogram distribution of observed seed factors. We also collected some spectral energy distributions (SEDs) of historical flare states to investigate the variation of $\gamma$-ray emission region. Those SEDs were fitted by both quadratic and cubic functions using the Markov-chain Monte Carlo method. Furthermore, we derived some physical parameters of blazars and compared them with the constraint of internal $\gamma\gamma$-absorption. We find that dusty torus dominates the soft photon fields of LSPs and most $\gamma$-ray emission regions of LSPs are located at 1–10 pc. The soft photon fields could also transition from dusty torus to broad line region and cosmic microwave background in different flare states. Our results suggest that the cubic function is better than the quadratic function to fit the SEDs.
Disordered eating (DE) is associated with elevated cardiometabolic risk (CMR) factors, yet little is known about this association in non-Western countries. We examined the association between DE characteristics and CMR and tested the potential mediating role of BMI. This cross-sectional study included 2005 Chinese women (aged 18–50 years) from the 2015 China Health and Nutrition Survey. Loss of control, restraint, shape concern and weight concern were assessed using selected questions from the SCOFF questionnaire and the Eating Disorder Examination-Questionnaire. Eight CMR were measured by trained staff. Generalised linear models examined associations between DE characteristics with CMR accounting for dependencies between individuals in the same household. We tested whether BMI potentially mediated significant associations using structural equation modelling. Shape concern was associated with systolic blood pressure (β (95 % CI) 0·06 (0·01, 0·10)), diastolic blood pressure (DBP) (0·07 (95 % CI 0·03, 0·11)) and high-density lipoprotein (HDL)-cholesterol (–0·08 (95 % CI –0·12, −0·04)). Weight concern was associated with DBP (0·06 (95 % CI 0·02, 0·10)), triglyceride (0·06 (95 % CI 0·02, 0·10)) and HDL-cholesterol (–0·10 (95 % CI –0·14, −0·07)). Higher scores on DE characteristics were associated with higher BMI, and higher BMI was further associated with lower HDL-cholesterol and higher other CMR. In summary, we observed significant associations between shape and weight concerns with some CMR in Chinese women, and these associations were potentially partially mediated by BMI. Our findings suggest that prevention and intervention strategies focusing on addressing DE could potentially help reduce the burden of CMR in China, possibly through controlling BMI.
Numerous studies have indicated that turbulence typically initiates along the boundary layer of the stationary disk within a rotor–stator cavity. To describe the transition process to turbulence on the stationary side of a closed rotor–stator cavity, a comprehensive approach combining global linear stability analysis with direct numerical simulation was adopted in the present study. The proposed model aligns with that of Yim et al. (J. Fluid Mech., vol. 848, 2018, pp. 631–647), who investigated the stability characteristics of the rotating-disk boundary layer in a rotor–stator cavity. In order to achieve a stable inflow for the stationary-disk boundary layer, we rotate the shroud together with the rotating disk. Through careful global stability analysis, the predominant spiral mode exhibiting the highest instability in the boundary layer of the stationary disk was discerned, corroborating observations from simulations. Initially, the spiral mode undergoes linear amplification, reaches a state of linear saturation and enters the nonlinear regime. Following nonlinear saturation in the flow field, a circular wave mode arises due to the influence of mean flow distortion. As the Reynolds number attained a sufficiently high level, the interplay between the downstream-propagating circular mode and spiral mode amplified disturbances in the boundary layer of the stationary disk, ultimately leading to the development of localised turbulence at the mid-radius of the rotor–stator cavity. Notably, the present study is the first to elucidate the coexistence of laminar–transitional–turbulent flow states in the stationary-disk boundary layer through direct numerical simulations.
The long- and finite-wavelength instabilities of weakly viscoelastic film on an oscillating inclined plane are investigated. By using the Chebyshev series solution with the Floquet theory, the combined effects of viscoelasticity and forcing amplitude on instability are described when the inclined plane oscillates in streamwise and wall-normal directions. For long-wavelength instability, the solution to the eigenvalue problem is obtained analytically by the asymptotic expansion method. Results show that the Floquet exponent is independent of the wall-normal oscillation amplitude. The effects of inclined angle, gravity and surface tension on the stability of viscoelastic liquid film are also discussed. For finite-wavelength instability, numerical results corresponding to the wall-normal oscillation disclose that with the increase of viscoelasticity, the unstable gravitational boundary moves to a higher wavenumber, and the critical amplitudes of subharmonic and harmonic instabilities are reduced. The neutral curve of gravity instability for streamwise oscillatory flow is divided into two parts, and a stable bandwidth is formed for a large value of the viscoelastic parameter. Besides, a new oscillatory mode is identified at small angles of inclination, which will be enhanced if the effect of viscoelasticity is incorporated.