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The cube‐like copper ferrite (CuFe2O4) nanocrystallines are produced by the hydrothermal method without using any surfactant. X‐ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT‐IR) are used to characterize the morphology, structure, and phase of the samples. CuFe2O4 nanocubes show the superior catalytic performance of reduction 4‐nitrophenol (4‐NP) to 4‐aminophenol (4‐AP). 20 mg CuFe2O4 nanocubes can totally convert 4‐NP to 4‐AP in 30 s at room temperature. Moreover, the reaction kinetics of 4‐NP catalytic reduction are also studied. Hence, this innovative CuFe2O4 nanocube has a lot of potential for organic pollutant destruction. [ABSTRACT FROM AUTHOR]

Background: The co-existence of meningioma and craniofacial fibrous dysplasia (CFD) is rare. Due to the similar radiological characteristics, it is challenging to differentiate such co-existence from solitary hyperostotic meningioma resulting in a dilemma of prompt diagnosis and appropriate intervention. Method: We conducted a retrospective review of the data from 21 patients with concomitant meningioma and CFD who were treated at Beijing Tiantan Hospital from 2003 to 2021. We summarized their clinicopathological features and performed a comprehensive literature review. Additionally, we tested the characteristic pathogenic variants in exon 8 and 9 of GNAS gene and the expression of corresponding α-subunit of the stimulatory G protein (Gαs) related to CFD to explore the potential interactions between these two diseases. Results: The cohort comprised 4 men and 17 women (mean age, 45.14 years). CFD most commonly involved the sphenoid bone (n = 10) and meningiomas were predominantly located at the skull base (n = 12). Surgical treatment was performed in 4 CFD lesions and 14 meningiomas. Simpson grade I-II resection was achieved in 12 out of the 14 resected meningiomas and almost all of them were classified as WHO I grade (n = 13). The mean follow-up duration was 56.89 months and recurrence was noticed in 2 cases. Genetic study was conducted in 7 tumor specimens and immunohistochemistry was accomplished in 8 samples showing that though GNAS variant was not detected, Gαs protein were positively expressed in different degrees. Conclusions: We presented an uncommon case series of co-diagnosed meningioma and CFD and provided a detailed description of its clinicopathological features, treatment strategy and prognosis. Although a definite causative relationship had not been established, possible genetic or environmental interplay between these two diseases could not be excluded. It was challenging to initiate prompt diagnosis and appropriate treatment for concomitant meningioma and CFD because of its similar radiological manifestations to meningioma with reactive hyperostosis. Personalized and multi-disciplinary management strategies should be adopted for the co-existence of meningioma and CFD. [ABSTRACT FROM AUTHOR]

The axial buckling load of single carbon fiber or composite strands is typically predicted using Euler's formula, developed for isotropic materials. This study introduces anisotropy in a mechanical carbon/epoxy Z‐pin model under axial pressure. It examines the influence of compressive modulus, shear modulus, off‐axis angle, and aspect ratio on its buckling behavior. Results show that the axial instability performance of the Z‐pin decreases with lower compression, shear modulus, and aspect ratio while keeping the tensile modulus fixed. Anisotropy decreases buckling load by up to 14% compared with Euler's formula, which only considers tensile modulus. Additionally, the impact of the deflection Angle between the pressure and pin‐axis can be ignored when it is less than 3°. Highlights: Euler formula overestimates composite Z‐pin buckling force under axial pressure.Anisotropy decreases buckling load by up to 14% for carbon/epoxy.Shear modulus is more influential on Z‐pin with a small aspect ratio.For off‐axial compression angles <3°, influence can be ignored. [ABSTRACT FROM AUTHOR]

In recent years, wind turbines have shown a maximization trend. However, most of the wind turbine blades operate in areas with a relatively poor natural environment. The stability, safety, and reliability of blade operation are facing many challenges. Therefore, it is of great significance to monitor the structural health of wind turbine blades to avoid the failure of wind turbine outages and reduce maintenance costs. This paper reviews the commonly observed types of damage and damage detection methods of wind turbine blades. First of all, a comprehensive summary of the common embryonic damage, leading edge erosion, micro-cracking, fiber defects, and coating defects damage. Secondly, three fault diagnosis methods of wind turbine blades, including nondestructive testing (NDT), supervisory control and data acquisition (SCADA), and vibration signal-based fault diagnosis, are introduced. The working principles, advantages, disadvantages, and development status of nondestructive testing methods are analyzed and summarized. Finally, the future development trend of wind turbine blade detection and diagnosis technology is discussed. This paper can guide the use of technical means in the actual detection of wind turbine blades. In addition, the research prospect of fault diagnosis technology can be understood. [ABSTRACT FROM AUTHOR]

In winter, wind turbines often face the risk of blade icing, and traditional methods – which mostly rely on manual observation and sensors – are limited by the experience of testers and costs; therefore, they are not widely used in practice. With the development of artificial intelligence, data-driven methods have garnered increased attention. However, it is challenging to mine the effective hidden information within data. In this regard, this paper proposes a wind turbine blade icing detection method based on feature engineering and the PSO-ConvLSTM-Transformer. Firstly, feature engineering is carried out with the help of expert experience to construct the mechanism variables related to icing; secondly, the ConvLSTM-Transformer prediction model is constructed to mine the timing information between supervisory control and data acquisition (SCADA) data, and finally, the model hyper-parameters are optimized by using the particle swarm optimization (PSO) algorithm to improve the diagnostic performance and generalizability of the model. The proposed model is evaluated using two wind turbine blade icing datasets. The proposed PSO-ConvLSTM-Transformer has significant advantages over multiple baseline models. This study can inform wind farm operations in terms of optimizing maintenance strategies, ensuring the safe and efficient operation of wind turbines in cold weather conditions. • Constructing ConvLSTM-Transformers deep learning model for wind turbine icing detection. • Explored the impact of domain knowledge-based icing mechanism features on deep neural networks. • Tested the effect of different optimization algorithms on the performance of deep learning models. [ABSTRACT FROM AUTHOR]

Optimal microcatheter shaping is essential for successful endovascular coiling procedures which is sometimes challenging. Our aim was not only to introduce a new shaping method using three-dimensional (3D) printed vessel models but also to prove its feasibility, efficiency and superiority. This was a retrospective cohort study. From September 2019 to March 2021, 32 paraclinoid aneurysms managed with endovascular coiling were retrospectively included and identified. Sixteen aneurysms were coiled using 3D microcatheter shaping method (3D shaping group), and traditional manual shaping method using shaping mandrels was adopted for another 16 patients (control group). The cost and angiographical and clinical outcomes between the two groups were compared, and the feasibility and effectiveness of the new 3D shaping method were evaluated and described in detail. With technical success achieved in 93.75%, most of the 16 shaped microcatheters using new shaping method could be automatically navigated into the target aneurysms without the assistance of microguidewires and could be assessed with favorable accessibility, positioning and stability. Twenty-seven out of 32 aneurysms (84.38%) were completely occluded with the rate of perioperative complications being 12.50%. Although there was no significant difference between the occlusion rates and complication rates of the two groups, the new shaping method could dramatically decrease the number of coils deployed and reduce the overall procedure time. Patient specific shaping of microcatheters using 3D printing may facilitate easier and safer procedures in coil embolization of intracranial aneurysms with shorter surgery time and less coils deployed. [ABSTRACT FROM AUTHOR]

Background: Craniofacial fibrous dysplasia is a fairly rare condition. Some literature have reported a few patients with craniofacial fibrous dysplasia suffering from vascular abnormalities. This study aimed to describe the possible coexistence of craniofacial fibrous dysplasia and cerebrovascular diseases for the first time.Method: We retrospectively reviewed the 1175 patients with craniofacial fibrous dysplasia in Beijing Tiantan Hospital and the information of the 22 patients coexisted with cerebrovascular diseases were described. In addition, we performed a systematic review for cases of craniofacial fibrous dysplasia with vascular abnormalities.Result: 22 out of 1175 patients (1.9%) were diagnosed with craniofacial fibrous dysplasia and cerebrovascular diseases including 9 intracranial aneurysms, 4 venous malformations, 2 arteriovenous malformations, 1 moyamoya disease, 2 intracranial venous stenosis and 4 cerebral ischemia with a mean age of 38.18 years old. Only 2 patients were managed surgically for craniofacial fibrous dysplasia and 6 patients were treated with neurosurgery for cerebrovascular diseases. 8 patients were closely followed and only 1 patient's symptoms worsened.Conclusion: Craniofacial fibrous dysplasia might cause constriction of the intracranial vessels and alteration of the overall hemodynamics of the intracranial vasculature resulting in various cerebrovascular diseases. Multimodal screening and examinations seems reasonable for patients with craniofacial fibrous dysplasia for throughout treatment and prognosis evaluations. [ABSTRACT FROM AUTHOR]

We aimed to study the clinical and radiological characteristics of intracranial tumors and explore the possible predictive value of these characteristics in relation to perioperative outcomes in elderly patients. We retrospectively identified 1535 elderly patients (aged 65 years and older) with intracranial tumors who underwent surgical resection between 2014 and 2018 in Beijing Tiantan Hospital. Factors associated with an increased risk of unfavorable perioperative performance and complications were investigated. Meningiomas were the most common tumors in the cohort (43.26%). The overall risk of perioperative death was 0.59%, and 42.80% of patients were discharged with unfavorable performance (Karnofsky Performance Scale [KPS] score ≤ 70). Of all patients, 39.22% had one or more complications after surgical resection. Aggressive surgery significantly lowered the rate of unfavorable perioperative outcomes (P = 0.000) with no increase in postoperative complications (P = 0.153), but it failed to be an independent predictor for perioperative outcomes in the multivariate analysis. Low performance status at admission (KPS ≤ 70) was independently associated with both unfavorable perioperative performance (P = 0.000) and complications (P = 0.000). In addition to the histopathological patterns of tumors, low performance status at admission is an independent predictor for both unfavorable perioperative performance and the occurrence of complications in elderly patients with intracranial tumors who have undergone surgical resections. However, age is not associated with perioperative outcomes in elderly patients. [ABSTRACT FROM AUTHOR]

An algorithm to assess the deviation of a machined workpiece model for a nominal part of the stereolithography (STL) model-based numerically controlled (NC) machining verification is presented, which is inspired by several algorithms used for evaluating the difference between two triangular meshes of similar shape, and some improvements are made. First, each triangle of the machined workpiece model is sampled under a user-defined sampling step δ. Then, the signed distance between each sample and the nominal part is computed to obtain the maximal error, minimal error, and mean error between the two STL models. Finally, a background grid is constructed to quickly search for the triangle closest to the sampling point. The experimental results demonstrate that the accuracy can be improved by sampling all the triangles, including those too small to be sampled under the current sampling step δ. The efficiency can be increased by applying a background grid, and the undercut and overcut areas can be easily detected by coloring the machined workpiece model according to the signed distance associated with each sample. [ABSTRACT FROM AUTHOR]

Methyl-CpG binding domain proteins (MBD) can specifically bind to methylated CpG sites and play important roles in epigenetic gene regulation. Here, we identified and functionally characterized the MBD protein in Tribolium castaneum. T. castaneum genome encodes only one MBD protein: TcMBD2/3. RNA interference targeting this gene at different developmental stages caused lethal phenotypes including metamorphosis deficiency in larvae and pupae, gastrointestinal system problems and fecundity deficiency in adult. Moreover, Tcmbd2/3 knockdown adult showed progressive reduced locomoter activity, a typical neurodegeneration phenotype. This is a common feature of DNA methylation in mammals and has not been found in other insects. However, band shift assays demonstrated that TcMBD2/3 could not bind to methylated DNA, indicating the essential roles of TcMBD2/3 is independent of DNA methylation. Our study provides Tcmbd2/3 plays important roles in T. castaneum and gives new insights into the potential mechanism of action of MBD proteins in insect. • A single methyl-CpG binding domain protein TcMBD2/3 was identified in Tribolium castaneum. • TcMBD2/3 is essential for metamorphosis, gastrointestinal system and reproductive activity in T. castaneum. • TcMBD2/3 plays important roles in neurogenesis of adult. • TcMBD2/3 lost the methylated DNA binding activity. [ABSTRACT FROM AUTHOR]

Legionella pneumophila encodes an extracellular secreted phospholipase A named PlaA that is translocated by the type II secretion system. It plays an essential role in maintaining the integrity of Legionella‐containing vacuoles in L. pneumophila pathogenesis. Here, it is shown that PlaA has a main lysophospholipase activity to hydrolyze fatty‐acyl groups in lysophospholipids. Although it has a very low phospholipase A activity to catalyze the hydrolysis of fatty‐acyl groups in phospholipids, PlaA can bind phospholipids such as 1,2‐dipalmitoylphosphatidylcholine with a dissociation constant of 11.1 µM. Sequence‐alignment analysis combined with activity assays revealed that PlaA contains a distinct substrate‐binding site among the known structures of the phospholipase A family, implying that PlaA may present a novel mechanism for substrate recognition. Native PlaA and its selenomethionine (SeMet)‐substituted form were purified and crystallized by vapour diffusion in hanging drops at 296 K. Diffraction data were collected to a resolution of 2.0 Å for native PlaA protein and to a resolution of 2.7 Å for SeMet‐substituted PlaA protein. The crystals of native PlaA belonged to the monoclinic space group P21, while the crystals of SeMet‐substituted PlaA belonged to the primitive orthorhombic space group P212121. Initial phases for PlaA were obtained from SeMet SAD data sets. [ABSTRACT FROM AUTHOR]

In recent years, researches in the field of salient object detection have been widely made in many industrial visual inspection tasks. Automated surface inspection (ASI) can be regarded as one of the most challenging tasks in computer vision because of its high cost of data acquisition, serious imbalance of test samples, and high real-time requirement. Inspired by the requirements of industrial ASI and the methods of salient object detection (SOD), a task mode of defect type classification plus defect area segmentation and a novel deeper and mixed supervision network (DMS) architecture is proposed. The backbone network ResNeXt-101 was pretrained on ImageNet. Firstly, we extract five multiscale feature maps from backbone and concatenate them layer by layer. In addition, to obtain the classification prediction and saliency maps in one stage, the image-level and pixel-level ground truth is trained in a same side output network. Supervision signal is imposed on each side layer to realize deeper and mixed training for the network. Furthermore, the DMS network is equipped with residual refinement mechanism to refine the saliency maps of input images. We evaluate the DMS network on 4 open access ASI datasets and compare it with other 20 methods, which indicates that mixed supervision can significantly improve the accuracy of saliency segmentation. Experiment results show that the proposed method can achieve the state-of-the-art performance. [ABSTRACT FROM AUTHOR]

Geometric accuracy is the major concern in numerically controlled (NC) milling simulation. Solid-based approach can provide more accurate geometric information, but it is of high computational cost. An efficient solid-based geometric NC simulation approach, by representing both cutter swept volume and initial or updated workpieces with triangular mesh and then performing consecutive Boolean subtractions to simulate the cutting process, is presented. The simulation efficiency is improved by applying two spatial decomposition methods including workpiece division and background grid to accelerate the spatial queries needed during the simulation process. The proposed approach was implemented, and the experimental results demonstrate that the simulation efficiency is improved significantly by applying spatial decomposition methods. [ABSTRACT FROM AUTHOR]

Building upon fully convolutional networks (FCNs), deep learning-based salient object detection (SOD) methods achieve gratifying performance in many vision tasks, including surface defect detection. However, most existing FCN-based methods still suffer from the coarse object edge predictions. The state-of-the-art methods employ intricate feature aggregation techniques to refine boundaries, but they are often too computational cost to deploy in the real application. This paper proposes a semantics guided detection paradigm for salient object detection. Guided atrous pyramid module is first applied on the top feature to segment complete salient semantics. Query context modules are further used to build relation maps between saliency and structural information from the top-down pathway. These two modules allow the semantic features to flow throughout the decoder phase, yielding detail enriched saliency predictions. Experimental results demonstrate that the proposed method performs favorably against the state-of-the-art methods on surface defect detection and SOD benchmarks. In addition, this method can detect at 27 FPS in a fully convolutional fashion without any post-processing, which has the potential for real-time detection. [ABSTRACT FROM AUTHOR]

• ER, AR and HR nonlinearly increased to gradient warming. • The nonlinear response of AR was closely related to TB. • The nonlinear response of HR was closely related to soil MBC. • Warming nonlinearly increased the AR/ER ratios but decreased the HR/ER ratios. • The nonlinear response of AR to gradient warming would dominate the ER response. Ecosystem respiration (ER) is greatly affected by global warming and responds nonlinearly to different warming levels. However, the mechanisms of the response of ER to gradient warming in paddy field remain obscure. Studying the effects and mechanisms of different warming levels on ER and its components in paddy field ecosystems will provide a theoretical basis for predicting future carbon budgets under climate change scenarios. In this study, 2-year gradient warming experiments with 5 warming treatments (+0 °C [control, CK], +0.3 °C [500 W warming, T1], +0.6 °C [1000 W warming, T2], +1.0 °C [1500 W warming, T3], +2.3 °C [3000 W warming, T4]) were performed by using a free air temperature increasing (FATI) system in paddy field in Northeast China. ER and its two components, autotrophic respiration (AR) and heterotrophic respiration (HR), were measured to reveal the mechanisms of the response of ER to gradient warming. The results showed that ER, AR and HR increased significantly under warming treatments and exhibited nonlinear responses to different warming levels. The maximum increases in ER, AR and HR appeared in the 1500 W warming treatment. The nonlinear response of AR was primarily related to total plant biomass (TB), while the nonlinear response of HR was closely related to soil microbial biomass carbon (MBC). Furthermore, warming nonlinearly enhanced the AR/ER ratios but reduced the HR/ER ratios. The AR/ER ratios were much greater than the HR/ER ratios. ER was closely correlated with its two components, and its nonlinear response might mainly derive from that of AR. The results highlight that the nonlinear response patterns of ER and its components to warming should be taken into global carbon cycling models to predict future carbon-climate feedbacks. [ABSTRACT FROM AUTHOR]

By applying displacement maps to slightly perturb two free-form surfaces, one can ensure exact agreement between the images in R3 of parameter-domain approximations to their curve of intersection. Thus, at the expense of slightly altering the surfaces in the vicinity of their intersection, a perfect matching of the surface trimming curves is guaranteed. This exact agreement of contiguous trimmed surfaces is essential to achieving topologically consistent solid model constructions through Boolean operations, and has a profound impact on the efficiency and reliability of applications such as meshing, rendering, and computing volumetric properties. Moreover, the control point perturbations require only the solution of a linear system for their determination. The basic principles of this approach to topologically consistent surface trimming curves are described, and example results from the implementation of a simple instance of the method are presented. [Copyright &y& Elsevier]

As a type of flow control technology, vortex generators (VGs) offer several advantages, including low cost, easy installation, and high practicality, making them widely used in engineering applications. This paper introduces a new rectangular VG design tailored for the NACA0015 flapped rudder, positioning it at the hydrofoil-flap junction to enhance hydrodynamic performance across various angles of attack (AOAs). Numerical simulations were conducted to analyze the near-wall flow patterns of the clean base rudder—both with and without gap sealing—as well as with traditional triangular and the newly designed rectangular VGs at deflection angles between 5° and 25° AOAs by Reynolds-Averaged Navier-Stokes (RANS) method. The results indicate that the specifically designed rectangular VGs effectively improve the lift coefficients and lift-to-drag ratio of the unsteady hydrofoil at different AOAs under a zero drift angle compared to traditional triangular VGs, with maximum enhancements of 9% and 15%, respectively. Moreover, the rudder's stability is enhanced, with the average oscillation of turning torque reduced by up to 18% at AOAs between 15° and 20°. These findings provide valuable insights into improving the hydrodynamic performance of flapped hydrofoils using VGs. • Investigate gap flow effects on the hydrodynamic performance of flapped rudders. • Propose a novel rectangular vortex generator tailored to flapped rudder characteristics. • Analysis on three-dimensional flow characteristics for unsteady hydrofoils under various rudder angles. • Demonstrate the optimized vortex generator's principle and its effect on hydrodynamic performance. [ABSTRACT FROM AUTHOR]

• The influence of fiber cutting at the composite grid intersection on the compressive behavior of laminate is studied. • The varied compressive performance of laminate induced by different fiber cutting methods is considered. • The reduction in compressive strength and dominant failure modes are accurately predicted and revealed. For thick composite grid structure, automated fiber placement (AFP) must be adopted to alternating cut fiber at the composite grid intersection to avoid out-of-plane fiber bending. In the present work, an experimental and numerical study has been carried out to understand and predict the influence of different cutting methods at the composite grid intersection on the compressive failure performance of laminate. Five kinds of test specimens with different cutting ratios were firstly manufactured and tested. A maximum of 67% drop in the compressive strength was recorded for the most severe cutting ratio. A High-speed camera was used to clarify the compressive failure progress of cut specimens. The dominant failure mechanism was classified into fiber fracture failure and inter-ply delamination. Further, numerical simulations were carried out to inform the deformation and failure mechanism of cut specimens. The FEM results correlated well with experiments in terms of location of dominant failure mode and strength knockdown for five different cutting configurations. These findings offered certain practical reference for the design and manufacture of thick AFP composite grid structures. [ABSTRACT FROM AUTHOR]

The problem of robust, angular velocity-free control and fault-tolerant control for liquid-filled flexible spacecraft attitude maneuver subject to unknown external disturbances is investigated. Moreover, state variables measurement uncertainty and actuator failures are explored. The liquid sloshing effect of spacecraft fuel is equivalent to a two-order spring-mass model, and the flexible attachments are equivalent to the Euler–Bernoulli beams. The external disturbance, multiple failures of the output actuator, and the coupled interference caused by liquid sloshing and vibrations of flexible attachments are distinguished as continuous and percussive disturbances. First, a fault-tolerant control method against the percussive disturbances is proposed, and the robustness performance and characteristics of this method are analyzed. Then, both continuous and percussive disturbances are considered to propose a new fault-tolerant control method based on a nonlinear disturbance observer, which is used to estimate the integrated disturbance. The Lyapunov stability theory proves that the proposed control strategy can make the state variables converge to a small neighborhood of the origin in finite time. Finally, the numerical simulation is used to verify the effectiveness and robustness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

In the postgenomics era, comparative genomics have advanced the understanding of evolutionary processes of neuropeptidergic signaling systems. The evolutionary origin of many neuropeptidergic signaling systems can be traced date back to early metazoan evolution based on the conserved sequences. Insect parathyroid hormone receptor (iPTHR) was previously described as an ortholog of vertebrate PTHR that has a well-known function in controlling bone remodeling. However, there was no sequence homologous to PTH sequence in insect genomes, leaving the iPTHR as an orphan receptor. Here, we identified the authentic ligand insect PTH (iPTH) for the iPTHR. The taxonomic distribution of iPTHR, which is lacking in Diptera and Lepidoptera, provided a lead for identifying the authentic ligand. We found that a previously described orphan ligand known as PXXXamide (where X is any amino acid) described in the cuttlefish Sepia officinalis has a similar taxonomic distribution pattern as iPTHR. Tests of this peptide, iPTH, in functional reporter assays confirmed the interaction of the ligand-receptor pair. Study of a model beetle, Tribolium castaneum, was used to investigate the function of the iPTH signaling system by RNA interference followed by RNA sequencing and phenotyping. The results suggested that the iPTH system is likely involved in the regulation of cuticle formation that culminates with a phenotype of defects in wing exoskeleton maturation at the time of adult eclosion. Moreover, RNAi of iPTHRs also led to significant reductions in egg numbers and hatching rates after parental RNAi. Author summary: Vertebrate parathyroid hormone (PTH) and its receptors have been extensively studied with respect to their function in bone remodeling and calcium metabolism. Insect parathyroid hormone receptors (iPTHRs) have been previously described as counterparts of vertebrate PTHRs, however, they are still orphan receptors for which the authentic ligands and biological functions remain unknown. We describe an insect form of parathyroid hormone (iPTH) by analyzing its interactions with iPTHRs. Identification of this new insect peptidergic system proved that the PTH system is an ancestral signaling system dating back to the evolutionary time before the divergence of protostomes and deuterostomes. We also investigated the functions of the iPTH system in a model beetle Tribolium castaneum by using RNA interference. RNA interference of iPTHR resulted in defects in wing exoskeleton maturation and fecundity. Based on the differential gene expression patterns and the phenotype induced by RNAi, we propose that the iPTH system is likely involved in the regulation of exoskeletal cuticle formation and fecundity in insects. [ABSTRACT FROM AUTHOR]

In automated fiber placement (AFP), the abrupt variations of orientations affect layup quality and kinematic performance. This paper proposes a quaternion-based orientation smoothing method constrained by the Domain of Admissible Orientation (DAO) to solve this problem. The DAO is the orientation domain attached to each orientation and defined by the interference avoidance and layup process constraints. All the placement orientations are interpolated into a quaternion curve, and the quaternion curve is smoothed by minimizing its energy function. The energy function is presented in three-dimensional (3D) space, so to facilitate this minimization, the DAO is also transformed into 3D space to constrain the orientation. Then, a spline shortcut generation (SPSG) algorithm is proposed to geometric smooth the curve by generating a spline passing through all DAOs. After that, a Resampling method nonlinearly optimizes the energy function by sampling the curve parameters to redefine the layup orientation within the DAO. Experiments show that the method effectively smooths the orientation trajectory under layup constraints and improves the kinematic performance of APF machines. [ABSTRACT FROM AUTHOR]

The performance of fiber‐reinforced composites is not only determined by their constituents, but also by the spatial distribution of inclusions. The traditional random distribution algorithm only considers the randomness of its relative position, and every newly generated fiber has to be checked with all the existing fibers, which requires a large amount of calculation. In this paper, inspired by the spreading process that the fibers are not arranged randomly, but the forces acting on the upper and lower rows of fibers. A random fiber distribution algorithm based on partition randomness is proposed, and a microscopic model of in‐plane fibers with random distribution is established. The maximum volume fraction of fibers generated by the algorithm is 75%, and the generation time is less than 20s. Statistical characterization and finite element analysis of the structure generated by the algorithm are compared with the experimental data to verify the randomness and effectiveness of fibers. The algorithm overcomes the jamming limit of the traditional hard‐core method, and can efficiently generate random microstructure models with different volume fractions, which can be a promising alternative for modeling and analysis of unidirectional fiber‐reinforced composites. [ABSTRACT FROM AUTHOR]

The uncertainty of wind speed has a great impact on the reliability of wind turbines. However, previous studies usually used average wind speed or rated wind speed as inputs, ignoring the impact of time and space distribution on wind speed. Based on the hourly ground observation data of meteorological stations, four observation stations are taken as the research object of the uncertainty of wind speed spatial distribution. The four observation stations are divided into single day and one week, and seven data analysis indicators and normal distribution models are used day and night to analyze the uncertainty of wind speed time distribution. The results show that both spatial distribution and temporal distribution are important factors that cause the uncertainty of wind speed. Due to different geographical locations of four stations, their wind speed time domain diagrams are different, and the maximum wind speed, fluctuation frequency and fluctuation amplitude of wind speed at each observation station are different; The wind speed distribution of a single day is quite different from that of a week. The data of a single day and a week are analyzed by day and night, which is quite different from the overall data analysis. The necessity of wind speed uncertainty research of wind turbine considering the temporal and spatial distribution is verified, and it is concluded that normal distribution is not suitable for fitting the distribution model of four stations under study, which lays a foundation for determining the wind speed distribution model, analyzing the power characteristics of wind turbine, evaluating the generation capacity of wind turbine, and analyzing the reliability of wind turbine. [ABSTRACT FROM AUTHOR]

This study concerns the importance of curing kinetic models for the prediction accuracy of the thermal overshoot in the curing process of thick polymeric composite plates. An adaptive activation energy (AAE) method was proposed to determine an accurate curing kinetic model with adaptive activation energy (CK‐AAE). Then the temperature field model of the autoclave curing process was established based on the CK‐AAE equations for predicting the curing thermal overshoot of thick polymer‐matrix composite plates. The prediction accuracy of the curing degree using the CK‐AAE model was improved greatly compared with the common curing kinetic models. And the predicted curing thermal overshoot of thick polymeric composite plates yielded good agreement with the measured results from the autoclave curing experiments. Moreover, it was observed that the curing thermal overshoot was more susceptible to the laminate thickness and less affected by the stacking sequence. [ABSTRACT FROM AUTHOR]

With the service environment of underwater vehicles gradually moving to the deep sea, the high load-bearing requirements lead to an increase in the thickness of the composite pressure hull, which not only reduces the molding quality but also increases the difficulty of design. Thus, in order to improve the design efficiency, a collaborative grading optimization method for geometry and layup of rib-reinforced ultra-thick composite pressure hull is proposed. Firstly, the sensitivity analysis of geometric parameters on weight, stability and strength of the pressure hull are conducted based on approximate model technology, and the reinforcement efficiency of different configurations under different length to diameter (L/D) ratios of hull is compared. Secondly, based on geometric factors and approximate model techniques, the complex ultra-thick layup optimization is gradually decomposed into bearing characteristics analysis, optimization of ply ratio, ply thickness and ply sequence. Finally, the results show that when the L/D ratio of the hull is less than 3, the hat-shaped rib has the best reinforcement efficiency, while the total thickness of the hull is large. Otherwise, the I-shaped rib is better. Compared with the mono-shell, the buoyancy factor of the optimized rib-reinforced configuration is reduced by 41%. • Geometry and layup collaborative optimization for rib-reinforced pressure hull. • Comparison of rib reinforcement efficiency under different L/D ratios of the hull. • Introducing geometric factor and ply units optimizes the ultra-thick hull layup. • The buoyancy factor of the optimized configuration is reduced by 41%. [ABSTRACT FROM AUTHOR]

• A layered pre-compaction scheme has been developed for curing ultra-thick composite laminates. • A novel uniaxial test method for ultra-thick composite laminates is proposed, and a heavy-duty compression test device is built. • High-modulus specimens have lower strength than low-modulus specimens due to premature delamination. • The test and simulation data of ultra-thick laminates are valuable reference for the design of ultra-thick structure. The damage mechanism of ultra-thick laminates widely used in aerospace and marine industries was obviously different from that of thin laminates. However, compression testing and simulation methods were generally limited to relatively thin laminates. To explore the compressive failure behavior of ultra-thick laminates, Firstly, a layered pre-compaction scheme was proposed to ensure the curing quality of ultra-thick laminates. A heavy-duty compression test equipment (accuracy reached 0.001 mm) was then developed, and a novel compression test method for ultra-thick composite laminates was proposed. The results showed that delamination played a key role in the failure behavior of ultra-thick laminates. The low interlaminar normal strength of ultra-thick laminates (55% of the 2 mm thin laminate) led to premature delamination, and wrinkle defects seriously reduced the compressive strength (11%). The compressive behavior for the matrix-dominant failure specimen predicted by the Puck criterion was the smallest (0.07%), while Tsai-Wu 3D predicted the smallest error (5.1%) for the delamination-dominant specimen. Finally, these findings are helpful for the design of ultra-thick composite structures. [Display omitted] [ABSTRACT FROM AUTHOR]

• A new method to improve the OHT strength of laminates by controlling different fine Z-pin arrangement angles was proposed. • The influence of Z-pins size parameters and the arrangement directions were investigated by experiments and simulations. • The tensile strength of fine Z-pin can reach 3500 Mpa without pore defects. • Fine Z-pins aligned 45°to the loading orientation improve open-hole tensile strength by up to 10%. The damage to structural performance caused by cut-out or holes is inevitable. In this paper, a new method to improve the tensile strength of open-hole laminates by using ultrasound-guided machine to control different fine Z-pin arrangement angles was proposed. The influence of systematically changing size parameters (0.11 mm, 0.28 mm and 0.5 mm diameters) and the direction of arrangement (unenhanced, parallel, vertical and 45° to the loading direction, respectively) were investigated by experiments and simulations. The production process of Ø 0.11 mm Z-pin with tensile strength up to 3500Mpa is firstly proposed. Z-pins with larger diameters have a certain inhibition effect on the depth of delamination damage, the connected resin-rich area seriously reduces the open-hole tensile strength when increasing the volume contents. In contrast, Ø 0.11 mm Z-pins can effectively reduce the strain level around the notch compared with the unpinned specimen. Ø 0.11 mm Z-pins aligned at 45° to the loading direction resulted in a 9% increase in open-hole tensile strength and a 54.1% reduction in delamination damage area. Finally, the simulation optimization is used to find that the 30° alignment has a better effect of suppressing delamination. [Display omitted] [ABSTRACT FROM AUTHOR]

Cuticle is not only critical for protecting insects from noxious stimuli but is also involved in a variety of metabolic activities. Cuticular proteins (CPs) affect cuticle structure and mechanical properties during insect growth, reproduction, and environmental adaptation. Here, we describe the identification and characterization of a member of the RR‐1 subfamily of CPs with an R&R consensus (CPR) in Tribolium castaneum (TcCPR69). Although it was previously reported to be highly expressed in the wings, we found that knocking down TcCPR69 by RNA interference (RNAi) did not cause obvious wing abnormalities but markedly disrupted the growth and metamorphosis of beetles with 100% cumulative mortality; additionally, the chitin content of the pharate adult was decreased and the new abdominal cuticle was significantly thinner before molting. TcCPR69 showed chitin‐binding ability and the expression levels of key genes involved in chitin metabolism (trehalase [TcTRE], chitin synthase [TcCHSA and TcCHSB], and chitinase [TcCHT5 and TcCHT10]) were also decreased by TcCPR69 knockdown. TcCPR69 gene expression peaked shortly after molting and was increased 2.61 fold at 12 h after 20‐hydroxyecdysone (20E) injection. This was reversed by RNAi of the ecdysone‐related genes ecdysone receptor (TcECR) and fushi tarazu transcription factor 1 (TcFTZ‐F1). These results indicate that TcCPR69 is positively regulated by 20E signaling to contribute to cuticle formation and maintain chitin accumulation during the growth and metamorphosis of beetles. [ABSTRACT FROM AUTHOR]

The autoclave curing process of the large-scale composite stiffened panel greatly affects the manufacturing quality of the component, especially the curing quality of stiffeners and the bonding quality between stiffeners and the panel. In this paper, a multi-objective optimization method is developed to optimize the curing cycle for the composite T-stiffened fuselage panel, which aims to minimize the temperature difference within the component to achieve better forming quality. The autoclave curing model considering thermal properties of composites is established and verified by the experiment first. The response surface models are then built up with the Finite Element Method (FEM) and the Box-Behnken Design (BBD). The fgoalattain algorithm is applied to solve the multi-objective optimization problem with nonlinear constraints. Results show that the maximum temperature difference of the two groups of monitoring points decreases by 22.91% and 21.42%, respectively. Besides, the total curing time is also reduced by 11 mins. [ABSTRACT FROM AUTHOR]

In recent years, increasing numbers of microRNAs (miRNAs) have been reported to regulate insect metamorphosis. One thousand, one hundred fifty‐four miRNAs have been previously identified from Tribolium castaneum by high‐throughput sequencing; however, little is known about which miRNAs can participate in metamorphosis, leaving the role of miRNAs in regulating the underlying mechanism elusive. Here, we report the participation of miR‐3017b in the metamorphosis of T. castaneum. Temporal profiles revealed that miR‐3017b was highly expressed at the late larval stage, but significantly decreased at the early pupal stage. Overexpression of miR‐3017b caused larval to pupal to adult metamorphosis arrested. Dual‐luciferase reporter assay and miRNA–mRNA interaction assay illustrated that miR‐3017b interacts with the coding sequence of sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) and suppresses its expression. Knockdown of SERCA caused metamorphosis arrested, similar to that observed in miR‐3017b overexpression beetles. Further functional mechanism analyses revealed that 20‐hydroxyecdysone application downregulates miR‐3017b and up‐regulates SERCA expression. The expression level of downstream genes in the 20E pathway was disrupted after overexpressing miR‐3017 and the knockdown of SERCA. These results provided evidence miR‐3017b‐SERCA contributes to metamorphosis by regulating the 20E pathway in T. castaneum. It could advance our understanding of the coordination of 20E and miRNA regulation in insect metamorphosis. [ABSTRACT FROM AUTHOR]

• TE-GDQ method as the solver of highly coupled partial differential equations of motion. • FSDT theory to approximate the displacement field of composite conical shell. • Generalized Maxwell constitutive law for modeling the magnetorheological elastomer matrix. • Modified rule of mixture and Halpin–Tsai micromechanical rule to numerical homogenize the composite media. • Tunable dynamic and damping of structures by using the MRE materials in the composites. This study explores the dynamic behavior of axially loaded conical shells composed of magnetorheological elastomer composites (MRECs). The investigation focuses on analyzing the impact of compressive loads on the frequencies and loss factors of these composites. The MRECs consist of laminates reinforced with fibers, enabling tunable viscoelastic properties through the utilization of magnetic fields. The equivalent mechanical characteristics of the MREC are calculated using the modified Voigt and Halpin–Tsai micromechanical rules. By employing the first-order shear deformation theory and Sanders-based strains, the kinematics of the conical shell are accurately modeled. A semi-analytical analysis, combining trigonometric expansion and the generalized differential quadrature (GDQ) methods, is employed to solve the system's highly coupled partial differential equations. Two consecutive analyses are performed. Firstly, the critical buckling load of the MREC conical shell is obtained through a stability analysis. Subsequently, the frequencies and loss factors of the shell in the pre-buckling zone are computed. Parametric analyses are conducted to study the impact of key factors, including magnetic field strength, compressive load magnitude, composite properties, geometric parameters, and boundary conditions. The proposed methodology is rigorously validated through meticulous accuracy and convergence analysis. The outcomes provide valuable insights into the dynamic response of axially loaded magnetorheological elastomer composite conical shells, highlighting their potential in adjustable dynamic and damping systems. [ABSTRACT FROM AUTHOR]

Objective: To study the protective effect of fecal microbiota transplantation (FMT) on experimental autoimmune encephalomyelitis (EAE) and reveal its potential intestinal microflora-dependent mechanism through analyses of the intestinal microbiota and spinal cord transcriptome in mice.Method: We measured the severity of disease by clinical EAE scores and H&E staining. Gut microbiota alteration in the gut and differentially expressed genes (DEGs) in the spinal cord were analyzed through 16S rRNA and transcriptome sequencing. Finally, we analyzed associations between the relative abundance of intestinal microbiota constituents and DEGs.Results: We observed that clinical EAE scores were lower in the EAE+FMT group than in the EAE group. Meanwhile, mice in the EAE+FMT group also had a lower number of infiltrating cells. The results of 16S rRNA sequence analysis showed that FMT increased the relative abundance of Firmicutes and Proteobacteria and reduced the abundance of Bacteroides and Actinobacteria. Meanwhile, FMT could modulate gut microbiota balance, especially via increasing the relative abundance of g_Adlercreutzia, g_Sutterella, g_Prevotella_9, and g_Tyzzerella_3 and decreasing the relative abundance of g_Turicibacter. Next, we analyzed the transcriptome of mouse spinal cord tissue and found that 1476 genes were differentially expressed between the EAE and FMT groups. The analysis of these genes showed that FMT mainly participated in the inflammatory response. Correlation analysis between gut microbes and transcriptome revealed that the relative abundance of Adlercreutzia was correlated with the expression of inflammation-related genes negatively, including Casp6, IL1RL2 (IL-36R), IL-17RA, TNF, CCL3, CCR5, and CCL8, and correlated with the expression of neuroprotection-related genes positively, including Snap25, Edil3, Nrn1, Cpeb3, and Gpr37.Conclusion: Altogether, FMT may selectively regulate gene expression to improve inflammation and maintain the stability of the intestinal environment in a gut microbiota-dependent manner. [ABSTRACT FROM AUTHOR]

This paper studies the merits of using knot interval notation for B-spline curves, and presents formulae in terms of knot intervals for common B-spline operations such as knot insertion, differentiation, and degree elevation. Using knot interval notation, the paper introduces MD-splines, which are B-spline-like curves that are comprised of polynomial segments of various degrees (MD stands for “multi-degree”). MD-splines are a generalization of B-spline curves in that if all curve segments in an MD-spline have the same degree, it reduces to a B-spline curve. The paper focuses on MD-splines of degree 1, 2, and 3, as well as degree 1 and n. MD-splines have local support, obey the convex hull and variation diminishing properties, and are at least Cn−1, where n is the smaller of the degrees of two adjoining curve segments. [Copyright &y& Elsevier]

Brake noise, a principal component of vehicle noise, is among the most critical measures of vehicle quality. The perceived quality of cars can be improved by reducing brake noise; therefore, vehicle manufacturers are extensively investigating the influencing factors, generating mechanism, and solutions of brake noise. Compressive strain is one of the most influential performance parameters of a brake pad and can be adjusted by regulating the material elastic modulus and by modifying the shape of the brake lining. In this study, the compressive strain of a brake pad was adjusted through four methods, and the noise characteristics of brake pads with different elastic modulus, section outlines, lining widths, and chamfers were studied through finite element analysis and the complex-eigenvalue method. The effects of compressive strain of a brake pad on brake noise were examined, and an optimized brake-pad scheme was developed. A dynamometer test conducted to validate the effectiveness of the optimized scheme confirmed a clear alleviation in brake noise. [ABSTRACT FROM AUTHOR]

Small heat shock proteins (sHSPs) are important modulators of insect survival. Previous research revealed that there is only one orthologous cluster of shsps in insects. Here, we identified another novel orthologous cluster of shsps in insects by comparative analysis. Multiple stress experiments and function investigation of Tchsp21.8a belonging to this orthologous cluster and seven species-specific shsps were performed in the stored-grain pest Tribolium castaneum. The results indicated that expression of Tchsp21.8a showed weak responses to different stresses. However, expressions of most species-specific shsps exhibited hyper-responses to heat stress, and expressions of all species-specific shsps displayed diverse responses during other stresses to protect beetles in a cooperative manner. Additionally, Tchsp21.8a and species-specific Tcshsp19.7 played important roles in the development of T. castaneum , and all Tcshsps had a certain impact on the fecundity. Our work created a comprehensive reliable scaffold of insect shsps that can further provide instructive insights to pest bio-control • Firstly identified another novel orthologous cluster of sHSPs in insects. • Two shsps were identified in Acrythociphon pisum and one new shsp was found in Anopheles gambiae. • Novel orthologous Tchsp21.8a in Tribolium castaneum had typical features of orthologous shsps. • Most species-specific Tcshsps were related to anti-heat stress by hundreds-fold up-regulation. • Species-specific Tcshsps did not respond to cold but had different responses under other stresses. [ABSTRACT FROM AUTHOR]

[Display omitted] • A geometric reconstruction approach based on consolidation and sweeping formation is proposed to characterize gap geometry. • A mechanical model on effects of AFP gaps is developed to study delamination failure of curved laminates. • The effect of AFP gaps on the bending strength of curved laminates varies with gap orientations. • 45°oriented gaps in spatial distribution greatly reduce the bending resistance of laminated panels. Automated placement technology has been widely used due to its excellent processing adaptability for large composite components with complex geometric structures. Whereas, it still poses challenges to study the effect of manufactured gaps induced by automated placement on curved composite parts. This study proposes a new geometric reconstruction approach based on consolidation and sweeping formation to model manufactured gaps. Additionally, a mechanical model incorporating the reconstructed geometry and the cohesive layer method is established to predict the physical behaviors of curved laminates. The micrograph of automated placement-induced gaps with 90° orientation was used to verify the rationality of the geometric reconstruction approach of gaps forming in the preparation process of composite materials. According to predictions of the proposed mechanical model, the effect of − 45° oriented gap defects on curved laminates was validated via four-point bending tests that confirmed alignment between predictions and experimental results for peak load, crack propagation, and failure patterns. Experimental results show that due to the differences in spatial local geometric features, orientations of gap defects would reduce the bending strength to different degrees and significantly affect the failure pattern of curved laminates. Furthermore, curved laminates with wider gaps experience a more considerable reduction in load-bearing capacity. [ABSTRACT FROM AUTHOR]

Latrophilin (LPH) is an adhesion G protein-coupled receptor (aGPCR) that participates in multiple essential physiological processes. Our previous studies have shown that lph is not only indispensable for the development and reproduction of red flour beetles (Tribolium castaneum), but also for their resistance against dichlorvos or carbofuran insecticides. However, the regulatory mechanism of lph -mediated insecticide susceptibility remains unclear. Here, we revealed that knockdown of lph in beetles resulted in opposing changes in two chemoreception genes, chemosensory protein 10 (CSP10) and odorant - binding protein C01 (OBPC01), in which the expression of TcCSP10 was downregulated, whereas the expression of TcOBPC01 was upregulated. TcCSP10 and TcOBPC01 were expressed at the highest levels in early pupal and late larval stages, respectively. High levels of expression of both these genes were observed in the heads (without antennae) of adults. TcCSP10 and TcOBPC01 were significantly induced by dichlorvos or carbofuran between 12 and 72 h (hrs) after exposure, suggesting that they are likely associated with increasing the binding affinity of insecticides, leading to a decrease in sensitivity to the insecticides. Moreover, once these two genes were knocked down, the susceptibility of the beetles to dichlorvos or carbofuran was enhanced. Additionally, RNA interference (RNAi) targeting of lph followed by exposure to dichlorvos or carbofuran also caused the opposing expression levels of TcCSP10 and TcOBPC01 compared to the expression levels of wild-type larvae treated with insecticides alone. All these results indicate that lph is involved in insecticide susceptibility through positively regulating TcCSP10 ; and the susceptibility could also further partially compensated for through the negative regulation of TcOBPC01 when lph was knockdown in the red flour beetle. Our studies shed new light on the molecular regulatory mechanisms of lph related to insecticide susceptibility. lph was involved in insecticide susceptibility through positively regulating TcCSP10 , and it could further partially compensate for insecticide susceptibility by negatively regulating TcOBPC01 when lph was knockdown in Tribolium castaneum. Unlabelled Image • TcCSP10 was down-regulated and TcOBPC01 was up-regulated after knockdown of Tclph. • TcCSP10 and TcOBPC01 were significantly induced by insecticides of dichlorvos or carbofuran. • RNAi of TcCSP10 and TcOBPC01 increased the susceptibilities of larval to insecticides. • Tclph related to insecticide susceptibility via regulating TcCSP10 and partially compensated by TcOBPC01. [ABSTRACT FROM AUTHOR]

Z-pinning is an effective method to improve the delamination resistance of composite laminates. The microstructure and manufacturing parameters have a great influence on the properties of z-pin composite laminates. In order to explore the influence of microscopic characteristic parameters on material properties and damage analysis, a parameterized RVE finite element model algorithm for automatic establishment of z-pin reinforced composites was proposed. The algorithm involves avoiding in-plane fibers to pin, generating fiber waviness, and assembling pin-fiber–matrix. Moreover, the statistical distribution of fiber misalignment angle can also be controlled. The developed program can generate RVE models with different parameters efficiently and quickly, such as fiber volume fraction, pin volume fraction, pin diameter, RVE size and fiber waviness. The statistical verification of the distribution of fiber misalignment angle can satisfy the probability distribution modeling of fiber angle. The generated model is divided into meshes, and finite element calculation can be realized. This work is of great significance to study the effects of microscopic characteristics on the properties and to optimize the design of z-pin reinforced composites. [ABSTRACT FROM AUTHOR]

The compressive strength drops sharply within 30 mm thick, but slowly when exceeding 30 mm thick. Delamination and fiber misalignment dominate the failure mechanism of ultra-thick laminate. Fiber waviness and voids contribute to the effect of thickness change on compressive strength. Higher interlaminar stresses S13 and S33 at the free edge induced premature delamination. As ultra-thick laminates are widely used in the field of aerospace and marine as the main load-bearing structure, extreme service conditions lead to increasing thickness of composite structures. However, the effect of the increase in thickness on the compressive properties of ultra-thick laminates is still unclear. Herein parameters including fiber volume fraction, fiber waviness, void content and free edge effect that affect the compressive strength with increasing thickness are studied. The results show that the fiber volume fraction of ultra-thick laminates does not change significantly with the increase of thickness due to the adoption of the zero-bleeding process, while the fiber waviness and void contribute to the thickness effect on compressive strength. On the other hand, the high interlaminar stress of the free edge contributes to the premature delamination of the specimen, which dominates the compressive strength of the ultra-thick laminate. Finally, compared with the thin laminate (2 mm), the compressive strength of ultra-thick laminate drops sharply (nearly 28%), but when the thickness increases from 30 to 70 mm, the drop of compressive strength is not obvious (only 10%). When the material and curing process are consistent, the weak interlaminar properties of ultra-thick laminates does not change significantly with the increase of thickness, which leads to the insignificant decrease in compression strength of ultra-thick laminates with the increase of thickness. The proposed empirical relationship between the compressive strength and thickness of quasi-isotropic laminates can provide important theoretical basis and experimental reference for the design of ultra-thick composite structures. [Display omitted] [ABSTRACT FROM AUTHOR]

Glutathione S-transferases (GSTs) are a large group of enzymes having both detoxification roles conferring insecticide resistance and specialist metabolic functions. Tribolium castaneum GST Delta 1 ( TcGSTd1 ) has been found playing crucial role in insecticide resistance and biological processes in insect species. However, the regulatory system of TcGSTd1 has still rarely been known. Comparing the transcriptome profile of RNAi treated larvae (ds- TcGSTd1 ) and control larvae of T. canstaneum by using RNA-sequencing, we obtained 14,284,085 sequence reads aligned with 13,275 genes. And 512 differentially expressed genes (DEGs) were identified from ds- TcGSTd1 treated group. Est/CCE , CYP , MRPs were significantly down-regulated in ds -TcGSTd1 group when compared with control group, which illustrated that they cooperated with TcGSTd1 to reduce the activity of cellular metabolism system. While, SNO was up-regulated in ds- TcGSTd1 insects suggested it may also involve in detoxifying alkaloid of insect metabolism system. These results established that TcGSTd1 not only acts as a vital gene for phase II cellular detoxification but also participates in phase 0, I, and III cellular detoxification by cooperating with CSPs , OBPs , CYP9 , ESTB1, CCE6 , MRPs and other detoxification genes. Knockdown of TcGSTd1 also suppressed several genes encoding antioxidant enzymes, e.g. CuZnSOD , Duox , Prx , HPX , CPO , and MCORP . Suggested that they may modulate the function of TcGSTd1 on lifespan, immune, development and reproduction. All these results shed the new insights into the regulatory mechanism of TcGSTd1 involved in insect physiology and could further facilitate the research of suitable and sustainable managements for the pest control. [ABSTRACT FROM AUTHOR]

This note conjectures that if two surface patches intersect with G1 continuity along an entire curve, the probability is one that the curve is rational. This idea has significance for surface intersection algorithms. [Copyright &y& Elsevier]

• Chat knockdown severely affected larval development and pupal eclosion, but vacht RNAi only disrupted pupal eclosion. • Parental RNAi of chat or vacht would reduce egg production and completely inhibite egg hatchability in T. castaneum. • Reduction of chat or vacht decreased the resistance to carbofuran and dichlorvos. Choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT) are essential enzymes for synthesizing and transporting acetylcholine (ACh). But their functions in metamorphosis, reproduction, and the insecticide susceptibility were poorly understood in the insects. To address these issues, we identified the orthologues of chat and vacht in Tribolium castaneum. Spatiotemporal expression profiling showed Chat has the highest expression at the early adult stage, while vacht shows peak expression at the early larval stage. Both of them were highly expressed at the head of late adult. RNA interference (RNAi) of chat and vacht both led to a decrease in ACh content at the late larval stage. It is observed that chat knockdown severely affected larval development and pupal eclosion, but vacht RNAi only disrupted pupal eclosion. Further, parental RNAi of chat or vacht led to 35 % or 30 % reduction in fecundity, respectively, and knockdown of them completely inhibited egg hatchability. Further analysis has confirmed that both the reduction in fecundity and hatchability caused through the maternal specificity in T. castaneum. Moreover, the transcript levels of chat and vacht were elevated after carbofuran or dichlorvos treatment. Reduction of chat or vacht decreased the resistance to carbofuran and dichlorvos. This study provides the evidence for chat and vacht not only involved in development and reproduction of insects but also could as the potential targets of insecticides. [ABSTRACT FROM AUTHOR]

This paper uses the Particle Image Velocimetry technique through wind tunnel experiments to investigate the spanwise velocity and vortex characteristics of a straight-bladed vertical axis wind turbine (VAWT) and to verify the reliability of the numerical simulation model. The aerodynamic forces are obtained by a multiport pressure measurement device. To assess the flow field of VAWT with bionic blades, this paper compares results between numerical simulations and experiments. Different flow field characteristics of wind turbines have been found in the baseline blades and bionic blades. The research shows that the bionic blade can suppress the influence of the tip vortex on the velocity of the cross-section z /(H /2) = 1.0, and the wake recovery velocity of VAWT with bionic blades is lower than that with baseline blades. By comparing the tangential force coefficients of the blades, it has been found that the tangential force of the bionic blades increases in azimuth angle regions 30°< θ < 116° and 193°< θ < 301°. It has also been proven that the aerodynamic performance of the bionic blade is slightly better than the baseline blades at TSR = 2.19. This study provides a better understanding of the development of aerodynamic forces and vortex characteristics through torque and velocity measurements. • The wind velocity around the blades are measured by the Particle Image Velocimetry (PIV) device. • Wake characteristics of the VAWT with bionic blades are investigated by contrasting with standard blades. • The bionic structure can suppress the influence of the tip vortex on the airflow. • The wake recovery of the VAWT with bionic blades is slower than that with standard blades. • The average power coefficient of the VAWT with bionic blades is bigger than that with standard blades. [ABSTRACT FROM AUTHOR]

[Display omitted] • New orthologous cluster of eclosion hormone-like (EHL) was identified in Arthropoda. • 20E up-regulated the expression of TcEHL during pupal-adult development. • RNAi of TcEHL caused lethal phenotypes with un-tanning adult cuticle in T. castaneum. • RNAi of TcEHL affected ecdysis behavior and tanning pathway genes in T. castaneum. Eclosion hormone (EH) is a neurohormone that plays a key role in the regulation of insect pre-ecdysis behavior at the end of each molt. Previous research has reported more than one EH gene was found in certain insects, with their functions and mechanisms still unclear. Here, aside from the classical EH gene orthologous group, we characterized another novel orthologous cluster of eclosion hormone-like (EHL) genes in Arthropoda and investigated the roles of EHL during development in Tribolium castaneum. T. castaneum EHL (TcEHL) shows high expression levels during pupal − adult development, which also positively responded to 20‐hydroxyecdysone (20E) treatment as well as RNA interference (RNAi) of ECR (20E nuclear receptor). Knockdown of TcEHL prevented the tanning of the adult cuticle and caused lethal phenotypes. Further analysis indicated that knockdown of TcEHL could upregulate expression levels of the classical TcEH , and downregulate the ecdysis behavior cascade genes, as well as tanning pathway enzymes. This suggests a critical role for TcEHL in adult eclosion and cuticle tanning. In addition, our data indicated that TcEHL is responsible for the female reproduction process. Taken together, these results suggest that TcEHL has specific roles in adult cuticle tanning during the post-eclosion process and female reproduction. They also suggest that EHL gene is the ancestral copy for the EH family and it is functionally shuffled by synfunctionalization. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of bionic airfoil on the aerodynamic characteristic and flow field of an H-type vertical axis wind turbine (VAWT). The pressure acting on the blade surface and flow field around the blade were predicted at different tip speed ratios (TSRs) and the angles of attack were predicted by numerical simulation. As a result, it was showed that the maximum value of lift force coefficient was 0.723 for baseline airfoil at the angle of attack 12° and was 0.743 for bionic airfoil at the angle of attack 14°. When the angle of attack was equal or greater than 14°, the static bionic airfoil showed better lift characteristic. Moreover, the maximum value of power coefficient occurred at TSR = 2.58 for the simulation, but the maximum value of torque coefficient was identified at TSR = 2.19. Meanwhile, the growth rates of the power coefficient were 7.02% at TSR = 1.38, 7.35% at TSR = 2.19, and 3.42% at TSR = 2.58 for simulation between baseline blades and bionic blades. The power performance of VAWT improved in dynamic stall for bionic airfoil by delaying stall on the blade's surface and promoting the laminar-to-turbulent transition to improve the power performance of wind turbine at the low TSRs for the mainstream wind velocity of 8.0 m/s. The research results were helpful to predict the performance of VAWTs under various wind environments and to improve the aerodynamic performance of VAWTs. • The power and torque coefficients of VAWT are obtained by wind tunnel experiments. • A bionic airfoil is selected to study power performance of VAWT. • Maximum lift coefficient of bionic airfoil is 0.743 at the angle of attack 14°. • Bionic bulge promotes the laminar-to-turbulent transition and delaying stall on blades surface. • Bionic airfoil improves power performance of an H-type VAWT. [ABSTRACT FROM AUTHOR]

This paper has attempted to investigate the aerodynamic characteristics of the straight-bladed vertical axis wind turbine (VAWT) with bionic blades for better application of bionic blades to VAWTs. The study was based on the computational fluid dynamics numerical simulation (CFD numerical simulation) technique to investigate the differences of the power and tangential force coefficients of the wind turbine between the bionic blades and standard blades at three different tip speed ratios (TSRs = 1.38, 2.19, and 2.58) for the mainstream wind velocity of 8.0 m/s. The results showed that the average power coefficient enhancing effect of the bionic blade increases as the TSR increases, and the average power coefficient of the bionic blade is higher than that of the standard blade mainly because of the high wind energy utilization in the wave trough section. Moreover, the power coefficients of the wave crest sections for bionic blades are better than that of the standard blades at the downstream region of 200° < θ < 260°. This research provides a reference for the use of bionic blades in the straight-bladed VAWT. • The aerodynamic characteristics of bionic blades for the VAWT are investigated. • The advantage of bionic blade is more significant as tip speed ratio increases. • The power coefficient of the trough section is higher than the crest section. • The bionic structure is beneficial for weakening the influence of tip vortex. [ABSTRACT FROM AUTHOR]