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Haemonchus contortus is a parasitic nematode that causes significant economic losses in ruminant livestock worldwide. In this study, we assessed the global genetic diversity and population structure of H. contortus using mitochondrial COX1 and ribosomal ITS2 sequences retrieved from the NCBI GenBank database. In total, 324 haplotypes of the COX1 and 72 haplotypes of the ITS2 were identified. The haplotype diversity values were all higher than 0.5, and the nucleotide diversity values were higher than 0.005. The Tajima’s D value for COX1 (−1.65634) was higher than that for ITS2 (−2.60400). Fu’s Fs, Fu and Li’s D (FLD), and Fu and Li’s F (FLF) values also showed high negative values, indicating a high probability of future population growth. In addition, the high fixation index (FST) value suggests significant genetic differentiation among populations. The haplotype networks of H. contortus populations based on COX1 sequences revealed clear geographic clustering, whereas ITS2 sequences showed more haplotype admixture across regions. The results of phylogenetic analyses were consistent with the haplotype networks. These findings highlighted that H. contortus populations exhibit significant genetic variation and are undergoing rapid population expansion, with clear genetic differences across geographic regions. This study established critical baseline data for future molecular epidemiology studies, which could guide region-specific parasite surveillance and targeted control strategies, thus helping to mitigate the risk of cross-border parasite transmission and drug resistance.
The hypersonic vehicle surfaces are subjected to intense thermal loads during atmospheric re-entry. Such conditions induce material ablation and structural deformation, potentially causing changes to aerodynamic configuration that critically endanger mission integrity. In this paper, a mathematical model of thermochemical non-equilibrium magnetohydrodynamics (MHD) at low magnetic Reynolds number is introduced to investigate the effects of MHD on the flow field. Variation of the magnetic pole angle (θ), the flow field profiles are quantitatively analysed, including gas component distributions and aerodynamic heating characteristics. Results indicate that the heat flux at the stagnation point initially decreases and then increases with θ increasing, reaching a minimum at θ = 60°. A portion of the heat flux from the blunt position is transferred to the shoulder (α between 30° and 60°). Notably, the shock standoff distance also shows a non-monotonic trend with θ increasing, peaking at θ = 30°, mirroring the effect of θ on the stagnation point heat flux. As θ increases, the component of the Lorentz force along the X-direction gradually increases, with its peak position corresponding to the shock standoff distance. The electrons and nitrogen atoms are primarily concentrated at the blunt nose, while nitric oxide and oxygen atoms are predominantly distributed along the vehicle wall. The dissociation region of the gas is influenced by the shock standoff distance, which increases as the shock standoff distance increases. At θ = 30°, the concentration of oxygen atoms, nitrogen atoms, nitric oxide molecules and electrons on the stagnation point line reaches its maximum. The present study provides a theoretical foundation for the application of MHD thermal protection methods on hypersonic vehicles.
Background: TERT promoter mutation (TPM) is an established biomarker in meningiomas associated with aberrant TERT expression and reduced progression-free survival (PFS). TERT expression, however, has also been observed even in tumours with wildtype TERT promoters (TP-WT). This study aimed to examine TERT expression and clinical outcomes in meningiomas. Methods: TERT expression, TPM status, and TERT promoter methylation of a multi-institutional cohort of meningiomas (n=1241) was assessed through nulk RNA sequencing (n=604), Sanger sequencing of the promoter (n=1095), and methylation profiling (n=1218). 380 Toronto meningiomas were used for discovery, and 861 external institution samples were compiled as a validation cohort. Results: Both TPMs and TERTpromoter methylation were associated with increased TERT expression and may represent independent mechanisms of TERT reactivation. TERT expression was detected in 30.4% of meningiomas that lacked TPMs, was associated with higher WHO grades, and corresponded to shorter PFS, independent of grade and even among TP-WT tumours. TERT expression was associated with a shorter PFS equivalent to those of TERT-negative meningiomas of one higher grade. Conclusions: Our findings highlight the prognostic significance of TERT expression in meningiomas, even in the absence of TPMs. Its presence may identify patients who may progress earlier and should be considered in risk stratification models.
The dynamic model of the distributed propulsion vehicle faces significant challenges due to several factors. The primary difficulties arise from the strong coupling between multiple power units and aerodynamic rudder surfaces, the interaction between thrust and vehicle dynamics, and the complexity of the aerodynamic model, which includes high-dimensional and high-order variables. To address these challenges, wind tunnel tests are conducted to analyse the aerodynamic characteristics and identify variables affecting the aerodynamic coefficients. Subsequently, a deep neural network is employed to investigate the influence of the power system and aerodynamic rudder on the aerodynamic coefficients. Based on these findings, a multi-dynamic coupled aerodynamic model is developed. Furthermore, a control-oriented nonlinear dynamics model for the distributed propulsion vehicle is established, and a flight controller is designed. Finally, closed-loop simulations for the climb, descent and turn phases are performed, validating the effectiveness of the established model.
A distributed cooperative guidance law without numerical singularities is proposed for the simultaneous attack a stationary target by multiple vehicles with field-of-view constraints. Firstly, the vehicle engagement motion model is transformed into a multi-agent model. Then, based on the state-constrained consensus protocol, a coordination control law with field-of-view (FOV) constraints is proposed. Finally, the cooperative guidance law has been improved to make it more suitable for practical application. Numerical simulations verified the effectiveness and robustness of the proposed guidance law in the presence of acceleration saturation, communication delays and measurement noise.
The objective of this study was to investigate the effects of different cockpit primary flight display (PFD) interface designs on pilot cognitive efficiency and cognitive load. This study designed five optimised PFD interfaces and conducted interface cognition experiments to assess cognitive responses across six different PFD interface designs, including the original design. It compared various subjective and objective metrics across different interface designs and evaluated the impact of each design factor on cognitive task performance. The experimental results show that the PFD interface in the original interface design performs better under different flight symbol designs, and the interface with 50% increase in font size performs better among interface designs with different font sizes with relatively lower cognitive load. This study provides experimental support and optimization suggestions for the optimal design of cockpit PFD interface, which can help improve pilots’ perception and operational capabilities, and thus enhance task performance efficiency and flight safety. Future research can investigate the effects of various design factors on the cognitive effects of the interface to enhance the ongoing improvement and optimisation of interface design.
In this paper, a brand-new adaptive fault-tolerant non-affine integrated guidance and control method based on reinforcement learning is proposed for a class of skid-to-turn (STT) missile. Firstly, considering the non-affine characteristics of the missile, a new non-affine integrated guidance and control (NAIGC) design model is constructed. For the NAIGC system, an adaptive expansion integral system is introduced to address the issue of challenging control brought on by the non-affine form of the control signal. Subsequently, the hyperbolic tangent function and adaptive boundary estimation are utilised to lessen the jitter due to disturbances in the control system and the deviation caused by actuator failures while taking into account the uncertainty in the NAIGC system. Importantly, actor-critic is introduced into the control framework, where the actor network aims to deal with the multiple uncertainties of the subsystem and generate the control input based on the critic results. Eventually, not only is the stability of the NAIGC closed-loop system demonstrated using Lyapunov theory, but also the validity and superiority of the method are verified by numerical simulations.
The purpose of this study was to explore the electroencephalogram (EEG) features sensitive to situation awareness (SA) and then classify SA levels. Forty-eight participants were recruited to complete an SA standard test based on the multi-attribute task battery (MATB) II, and the corresponding EEG data and situation awareness global assessment technology (SAGAT) scores were recorded. The population with the top 25% of SAGAT scores was selected as the high-SA level (HSL) group, and the bottom 25% was the low-SA level (LSL) group. The results showed that (1) for the relative power of $\beta$1 (16–20Hz), $\beta$2 (20–24Hz) and $\beta$3 (24–30Hz), repeated measures analysis of variance (ANOVA) in three brain regions (Central Central-Parietal, and Parietal) × three brain lateralities (left, midline, and right) × two SA groups (HSL and LSL) showed a significant main effect for SA groups; post hoc comparisons revealed that compared with LSL, the above features of HSL were higher. (2) for most ratio features associated with $\beta$1 ∼ $\beta$3, ANOVA also revealed a main effect for SA groups. (3) EEG features sensitive to SA were selected to classify SA levels with small-sample data based on the general supervised machine learning classifiers. Five-fold cross-validation results showed that among the models with easy interpretability, logistic regression (LR) and decision tree (DT) presented the highest accuracy (both 92%), while among the models with hard interpretability, the accuracy of random forest (RF) was 88.8%, followed by an artificial neural network (ANN) of 84%. The above results suggested that (1) the relative power of $\beta$1 ∼ $\beta$3 and their associated ratios were sensitive to changes in SA levels; (2) the general supervised machine learning models all exhibited good accuracy (greater than 75%); and (3) furthermore, LR and DT are recommended by combining the interpretability and accuracy of the models.
Vitamin D deficiency and insufficiency have been found in general population but especially in women of childbearing age. Although Vitamin D can be obtained from food source (few naturally) and produced from skin sunlight exposure, it can come from a reliable source via supplementation. Supplementing 15 µg daily could meet the recommended dietary allowance for 19 years and older and 20 µg for 70 years older. Daily supplementation greater than 100 µg is not recommended. Unlike water-soluble vitamins B and C, Vitamins A, D, E, and K are fat-soluble. This property of Vitamin D affects not only the delivery of it in drink but also absorption at the small intestine and bioavailability (i.e., serum level). This study focused on enhancing the solubility of vitamin D using a novel botanical solubilizer. Using rubusoside (RUB), isolated from stevia and other plants, Vitamin D3 (cholecalciferol; VD3) was experimented for solubility enhancement. VD3 was processed with RUB to form the VD3-RUB structure in powder form. Solubility of this powder in physiologic solutions of water, gastric or intestinal fluid, stability over time, and dilutability for achieving desired supplementation levels were examined. The VD3-RUB complex structure in water solution was characterised for particle size and shape using dynamic light scattering techniques. VD3 in water solution after filtration was quantified on HPLC. VD3 was practically insoluble in water. However, in the presence of 10% w/v RUB as the botanical solubilizer, VD3 became soluble in water to a concentration of 4,500 µg/mL. This water-soluble concentrate appeared clear and was freely dilutable to a drink containing amounts of VD3 ranging from 15 µg to 100 µg. Particle size analysis indicated the presence of approximately 4 nm spherical particles. HPLC analysis of the water solution detected RUB and VD3. These drinks were stable and remained clear and transparent for at least eight weeks. A packet of water-soluble Vitamin D3 powder was also developed for addition to a glass of water in the amount of 15 µg VD3. The packet, similar to the instant coffee powder, produced an instant Vitamin D drink containing the recommended dietary allowance of 15 µg. The water-soluble VD3 powder was also dissolvable in simulated gastric fluid and intestinal fluid, and stable for at least two hours. This solubility enhancement could aid in absorption and improve oral bioavailability, seen in the work with oily ceramides(1) and insoluble curcumin(2). It is especially advantageous for making drinks as the solubilizer is generally regarded as safe by the US FDA.
It is well-known that many modern lifestyles, including the use of artificial light, shift work, irregular or short sleep, sedentary activity, and unhealthy diet can disrupt the circadian rhythm. This disruption can result in the so-called Circadian Syndrome (CircS) which has been identified as a risk factor for a variety of chronic diseases. The concept of Circadian Syndrome (CircS) was first proposed by Zimmet et al in 2019. CircS has been shown to be a better predictor for cardiovascular diseases (CVD) than the metabolic syndrome (MetS) in adults in China and USA 1,2. Dietary patterns are found to be associated with CircS 3, whereby western dietary pattern was positively related, while prudent pattern was inversely associated, with CircS in the US adults. However, no prior study has investigated the association between fiber intake and CircS. We, thus, aimed to fill this research gap. We analysed data from 10,486 adults aged 20 years and above years who attended the 2005-2016 National Health and Nutrition Examination Survey (NHANES). Fiber and other nutrients intake were assessed using two days 24 hours recall. CircS was derived from all five components of MetS (i.e. central obesity, elevated fasting glucose, elevated triglyceride, reduced HDL-Cholesterol and elevated blood pressure), in addition to short sleep (sleep duration <6 hours/day) and depressive symptoms (PHQ-9 score ≥5). A cut-off for CircS was set as ≥ 4 components. Multivariable logistic regression was used to assess the association between fiber intake and CircS. Mean age of participants was 50.3(SD 17.6) years, and 41.3% had CircS. The mean (SD) fiber intake was 7.8 (2.1), 12.9 (1.3), 17.9 (1.7), and 28.9 (8.2) g/day across the quartiles of fiber intake. The prevalence of CircS decreased across quartiles of fiber intake (44.5% in Q4 and 37.1% in Q1). In the multivariable logistic model adjusting for age, gender, ethnicity, energy intake, education and lifestyle factors, across the quartiles of fiber intake, the odds ratios (ORs) (95%CI) for CircS were: 1.00, 0.91 (0.76-1.08), 0.82 (0.70-0.96), 0.79 (0.63-0.98) (p trend 0.012), respectively. No significant interactions were found between fiber intake and race, gender, smoking, alcohol drinking, and physical activity, in relation to CircS. In conclusion, a high fiber intake was associated with a lower prevalence of CircS among US adults. The findings highlight the importance of fiber intake for the prevention of metabolic and circadian syndrome, suggesting a potentially accessible and cost-effective lifestyle approach to improve public health. Our results underscore the concern that most of the US adults had fiber intake below the recommended level. Longitudinal studies are needed to validate the findings in different populations.
Echinococcosis poses a significant threat to public health. The Chinese government has implemented prevention and control measures to mitigate the impact of the disease. By analyzing data from the Chinese Center for Disease Control and Prevention and the State Council of the People’s Republic of China, we found that implementation of these measures has reduced the infection rate by nearly 50% between 2004 to 2022 (from 0.3975 to 0.1944 per 100,000 person-years). Nonetheless, some regions still bear a significant disease burden, and lack of detailed information limites further evaluation of the effects on both alveolar and cystic echinococcosis. Our analysis supports the continuing implementation of these measures and suggests that enhanced wildlife management, case-based strategies, and surveillance systems will facilitate disease control.
In this paper, we investigate the constrained attitude control problem of hypersonic vehicles (HVs). An improved prescribed performance dynamic surface control method is proposed based on an adaptive scaling strategy. Because of the uncertain time-varying disturbances, the controlled state may violate the constraint in the prescribed performance control (PPC) framework. An adaptive scaling strategy is introduced in the PPC method to avoid state violation. The performance function is scaled with respect to the state adaptively. Moreover, a nonlinear disturbance observer is used to compensate the sum of external and other internal disturbances of the system. The proposed method improves the system dynamic performance while ensuring the system robustness. Furthermore, the stability of the closed-loop system is proved by Lyapunov analysis. Finally, numerical simulations are implemented to verify the effectiveness of the PPC method and superiority over other methods.
The boundary layer thickness on a compressor blade suction surface increases rapidly under a adverse pressure gradient and even separates from the blade surface. This paper proposes a novel method for developing the slot inside the blade, with the inlet of the slot located at the leading edge of the blade and the outlet located at the suction surface, using the momentum of the incoming flow to form a high velocity jet to control the boundary layer on the suction surface. For a plane cascade with a diffusion factor of 0.45, the effects of the main slot parametres (such as the shape of the slot and the positions of the slot inlet and outlet) on the flow in the slot, the flow field and the aerodynamic performance of the cascade were investigated with a numerical method. When the aerodynamic performance of cascades with slotted and unslotted blades was compared, it was found that a reasonable slot structure can effectively inhibit the development of the boundary layer on the blade suction surface and greatly improve the aerodynamic performance of the cascade. Based on the influence of the slot parametres of the above cascade, the slot of a plane cascade with a diffusion factor of 0.60 was designed. The numerical calculation results show that the slotted cascade with a diffusion factor of 0.60 outperformed the slotted cascade with a diffusion factor of 0.45. This result showed that the higher the cascade load, the greater the performance improvement from slotting. Furthermore, the unslotted and slotted cascades were tested, and the test results agreed well with the calculations. The aerodynamic performance of the slotted cascade was better than that of the unslotted cascade, which verifies the accuracy of the calculation method and the feasibility of blade slotting for suppressing the development of boundary layers on suction surfaces and reducing flow loss.
In this paper, an adaptive neural output-constrained control algorithm is proposed for a class of non-affine kinetic kill vehicle (KKV) systems. The key point is that the non-affine control law can be designed and the output of the KKV system conform to the output limit with the aid of the proposed method. Due to the aerodynamic moments, the actual control torque is non-affine, which can be addressed by introducing an integral process to the design of the controller. Besides, in order to improve the control precision, a nonlinear mapping is put forward so that the output constraint can be transformed to the constraint of the introduced dynamic signal that can be simply achieved. From the simulation results it can be concluded that the states of the KKV system can track the desired trajectories in spite of different working conditions and the control precision is higher compared with other control methods.
It has been previously identified that levels of peripheral inflammatory proteins, such as cytokines, are altered in people with schizophrenia spectrum disorders (SSD).
Objectives
As there is considerable inconsistency in the literature with respect to how inflammatory profiles differ between acute and chronic stages of SSD, a systematic review and network meta-analysis was performed.
Methods
Records from CINAHL, the Cochrane Central Register of Controlled Trials, EMBASE, PubMed, and PsycINFO were systematically searched from inception until 31 March 2022 for published studies that had measured levels of inflammatory proteins in cases of SSD and healthy controls. Pairwise and network meta-analyses were performed to determine whether there were significant differences in mean peripheral protein concentrations between acute SSD, chronic SSD, and healthy controls.
Results
After application of the screening process, 215 articles were included for data-analysis. One group of markers were consistently elevated (p<0·05) in both acute and chronic SSD, relative to healthy controls; this group comprised interleukin (IL)-1β, IL-1 receptor antagonist (IL-1RA), soluble interleukin-2 receptor (sIL-2R), IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, and high sensitivity C-reactive protein (hsCRP). A second group of markers were inconsistently altered between illness stages: IL-2 and interferon (IFN)-γ were significantly elevated (p<0·05) in acute SSD, whilst IL-4, IL-12 and IFN-γ were significantly decreased (p<0·05) in chronic SSD.
Conclusions
These results indicate that a baseline level of inflammatory protein alteration occurs in SSD throughout the course of illness. This was evident from the group of markers that were consistently elevated in acute and chronic SSD (e.g., IL-6), representing possible trait markers. Moreover, superimposed immune activity may occur in acute SSD, given the group of possible state markers that were increased only in acute illness (e.g., IFN-γ). Further research is required to elucidate whether these peripheral changes are reflected within the central nervous system.
Vortex shedding in the wake of a cylinder in uniform flow can be suppressed via the application of a porous coating; however, the suppression mechanism is not fully understood. The internal flow field of a porous coated cylinder (PCC) can provide a deeper understanding of how the flow within the porous medium affects the wake development. A structured PCC (SPCC) was three-dimensionally printed using a transparent material and tested in water tunnel facilities using flow visualisation and tomographic particle image velocimetry at outer-diameter Reynolds numbers of $Re = 7 \times 10^{3}$ and $7.3 \times 10^{4}$, respectively. The internal and near-wall flow fields are analysed at the windward and mid-circumference regions. Flow stagnation is observed in the porous layer on the windward side and its boundary is shown to fluctuate with time in the outermost porous layer. This stagnation region generates a quasi-aerodynamic body that influences boundary layer development on the SPCC inner diameter, that separates into a shear layer within the porous medium. For the first time via experiment, spectral content within the separated shear layer reveals vortex shedding processes emanating through single pores at the outer diameter, providing strong evidence that SPCC vortex shedding originates from the inner diameter. Velocity fluctuations linked to this vortex shedding propagate through the porous layers into the external flow field at a velocity less than that of the free stream. The Strouhal number linked to this velocity accurately predicts the SPCC vortex shedding frequency.
The target backsheath field acceleration mechanism is one of the main mechanisms of laser-driven proton acceleration (LDPA) and strongly depends on the comprehensive performance of the ultrashort ultra-intense lasers used as the driving sources. The successful use of the SG-II Peta-watt (SG-II PW) laser facility for LDPA and its applications in radiographic diagnoses have been manifested by the good performance of the SG-II PW facility. Recently, the SG-II PW laser facility has undergone extensive maintenance and a comprehensive technical upgrade in terms of the seed source, laser contrast and terminal focus. LDPA experiments were performed using the maintained SG-II PW laser beam, and the highest cutoff energy of the proton beam was obviously increased. Accordingly, a double-film target structure was used, and the maximum cutoff energy of the proton beam was up to 70 MeV. These results demonstrate that the comprehensive performance of the SG-II PW laser facility was improved significantly.