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Abstract Background Genetic factors, including the Hedgehog Interacting Protein (HHIP) gene, play a crucial role in Chronic Obstructive Pulmonary Disease (COPD) susceptibility. This study examines the association between HHIP gene polymorphisms and COPD susceptibility, phenotypes, and serum IL-17 and IL-18 levels in a Han Chinese population. Methods A case-control study was conducted with 300 COPD patients and 300 healthy controls in Chinese Han population. Participants underwent genotyping for HHIP gene polymorphisms, pulmonary function tests, and quantitative CT scans. DNA samples were sequenced using a custom chip targeting the HHIP gene. Serum IL-17 and IL-18 levels were measured by enzyme-linked immunosorbent assay. Associations between SNPs, COPD susceptibility, and phenotypes were analyzed using logistic and multiple linear regression models, adjusting for confounders. Results Our study identified the rs11100865 polymorphism in the HHIP gene as significantly associated with COPD susceptibility (OR 2.479, 95% CI 1.527–4.024, P = 2.39E-04) after screening 114 SNPs through rigorous quality control. Stratified analyses further indicated this association was particularly in individuals aged 60 or older. Serum levels of IL-17 and IL-18 were significantly elevated in COPD patients compared to controls, with rs11100865 showing a notable association with IL-18 levels (B = 49.654, SE = 19.627, P = 0.012). However, no significant associations were observed between rs11100865 and serum IL-17 levels, COPD-related imaging parameters, or clinical phenotypes. Conclusion This study identified a significant association between HHIP gene polymorphisms and COPD susceptibility in a Han Chinese population, with connections to inflammation, but found no significant associations between this SNP and COPD-related imaging or clinical phenotypes. Trial registration www.chictr.org.cn ID: ChiCTR2300071579 2023-05-18.

Sub-atmospheric pressure environment and oscillation laser are both excellent ways to improve welded joint quality. However, the differences in their effects and mechanisms are unclear. Therefore, the differences between sub-atmospheric pressure and oscillating laser in weld formation, porosity suppression and grain size refinement were analyzed in this study. The results revealed that penetration depth of welded joint was increased to 6.09 mm under sub-atmospheric pressure environment while it was decreased to 3.3 mm under oscillation laser. Furthermore, reducing fluctuating vapor pressure and suppressing vortex formation were the main means to improve the keyhole stability and promote the escape of bubbles in a sub-atmospheric pressure environment. The improvement of the oscillating laser in these two aspects was attributed to enlarging keyhole area, shortening escape path and oscillation keyhole absorption. Additionally, the average grain size in the upper weld was reduced from 134.6 μm to 118.6 μm and 114.1 μm under the sub-atmospheric pressure environment and laser oscillation, respectively. The reduction of the temperature gradient led to former grain refinement while the increase of heterogeneous nucleation rate was responsible for latter grain refinement. Correspondingly, the mechanical properties of welded joints were improved. The study offered valuable insights for the application of laser welding with oscillation laser and sub-atmospheric pressure in industrial production.

ObjectiveTo investigate the choice of treatment options and long-term orthopedic results of congenital kyphosis in children due to anterior vertebral bone bridges.MethodsThe clinical data of children with congenital kyphosis due to anterior vertebral bridges treated at our center from May 2005 to May 2020 were retrospectively analyzed. We evaluated the clinical features of the deformity, the choice of treatment plan, the change in the Cobb angle of the kyphosis and the improvement of the sagittal trunk deviation before and after treatment and at the final follow-up visit by means of pre-treatment and post-treatment imaging, physical examination and analysis of the case data.ResultsA total of 35 children were included. Clinical follow-up was conducted on a cohort of 5 children, all of whom presented with type Ⅱ congenital kyphosis caused by less than three thoracic anterior bone bridges. The study findings revealed no noteworthy advancement in segmental kyphosis, thoracic kyphosis, lumbar lordosis, and sagittal vertical axis during the final follow-up assessment (p > 0.05). In a cohort of 30 pediatric patients who underwent surgical intervention, segmental kyphosis was corrected, with a decrease from an average angle of (40.1 ± 20.5)° to (15.6 ± 9.5)°. Furthermore, significant improvements were noted in segmental kyphosis, thoracic kyphosis, lumbar lordosis, and sagittal vertical axis at the postoperative stage compared to the preoperative stage (p

Multitarget tracking technology is the core topic in the field of intelligent driving. Multi-target complex manoeuvring, measurement outliers and unknown environmental prior parameters strongly affect the tracking accuracy of the target state. To address the accurate tracking of multitarget under the above complex working conditions, we propose a new multitarget tracking algorithm, named the Multiconstrained Generalized Probabilistic Data Association Filtering (MCGPDAF) algorithm. In this algorithm, we use the target position and heading information to construct constraint parameters to calculate the association probability between each effective measurement combination and the target track. This algorithm can effectively suppress the measurement association anomalies and aprior information errors, as well as enable the robust association of single-sensor multitarget measurements and accurate tracking of target states under complex working conditions. On this basis, a multitarget tracking method based on composite perception fusion is further constructed, and the correlation sequential track association algorithm and covariance cross fusion algorithm are used to enable the track association and the estimation and fusion of target states among multiple sensors, which further enhances the tracking accuracy of the multitarget state. The simulation and real vehicle experiment results reveal that, compared to current advanced algorithms, the RMSE and MAPE of the MCGPDAF algorithm for multitarget tracking are enhanced by an average of 23.97% and 24.35%, respectively. Additionally, the MOTA and MOTP of the MCGPDAF algorithm improve by an average of 14.68% and 15.71%. Moreover, compared to single-sensor multitarget tracking, the RMSE and MAPE of composite perception fusion results based on the MCGPDAF algorithm are further enhanced by 26.43% and 27.15% on average, which reflects the practicality of the tracking method showcased in this research.

The present study investigated the inhomogeneity of microstructure and properties of hybrid laser-MIG welded 10-mm-thick 316L/AH36 joints. The study focused on the inhomogeneity of the laser zone, hybrid zone, and transition zone. The temperature field was simulated using ABAQUS and showed a higher cooling rate in the laser zone. As a result, the microstructure in the laser zone was dominated by martensite while that in the hybrid zone was composed of 84 % austenite and 16 % ferrite. The laser zone showed poorer impact toughness and corrosion resistance than the hybrid zone. However, the corrosion resistance of the whole weld was the worst. Because the inhomogeneous microstructure formed a galvanic couple that accelerated the corrosion process. This work indicated that the energy ratio (the ratio of laser to arc energy) should be considered in the welding of dissimilar thick steel to reduce the inhomogeneity in the two zones and obtain a desirable property balance among hardness, toughness, and corrosion resistance.

External magnetic field has been employed to improve appearance and suppress defects in the single laser or arc welding, and its physical mechanism in magnetic-field-assisted single laser or arc welding has been clearly clarified. However, few studies on the physical processes in magnetic-field-assisted laser-arc hybrid welding (MFA-LAHW) are conducted and its influencing mechanism is unclear. In this research, a comprehensive three-dimension numerical model is established to investigate the keyhole dynamics and weld pool behaviors in MFA-LAHW under the effect of different magnetic flux density. The results suggest that the interaction between a lower magnetic flux density (≤30 mT) and welding current is induced due to the existence of arc. Compared to the magnetic-field-assisted laser beam welding (MFA-LBW), this interaction induces a stronger Lorentz force up to the order of magnitude of 105 N/m3. The weld pool width is reduced while its length and height are increased because the Lorentz force facilitates the backward flow of thermal fluid, increasing the heat transfer from the keyhole and droplet to the rear weld pool edge. Moreover, the steady magnetic field improves the keyhole stability. The deform on keyhole rear wall brought by the droplet and vortex is suppressed, and keyhole size is widened under steady magnetic field, which reduced keyhole collapse. Furthermore, the comparative analysis with the case in MFA-LBW is carried out and the MFA-LAHW is verified to be more valuable for medium-thickness aluminum alloy. This work provides the underlying physics understanding of MFA-LAHW, which will broaden the application value of LAHW.

To achieve laser direct welding of glass and metal without optical contact is hard, owing to the large difference in thermal expansion and thermal conductivity between glass and metal and an insignificant melting area. In this study, the high-power picosecond pulsed laser was selected to successfully weld the aluminosilicate glass/6061 aluminum alloy with a gap of 35 ± 5 μm between glass and metal. The results show that the molten glass and metal diffuse and mix at the interface. No defects such as microcracks or holes are observed in the diffusion mixing zone. Due to the relatively large gap, the glass collapsed after melting and caulking, resulting in an approximately arc-shaped microcrack between modified glass and unmodified glass or weakly modified glass. The shape of the glass modification zone and thermal accumulation are influenced by the single-pulse energy and linear energy density of the picosecond laser during welding, resulting in variations in the number and size of defects and the shape of the glass modification zone. By reasonably tuning the two factors, the shear strength of the joint reaches 15.98 MPa. The diffusion and mixing at the interface and the mechanical interlocking effect of the glass modification zone are the main reasons for achieving a high shear strength of the joint. This study will provide reference and new ideas for the laser transmission welding of glass and metal in the non-optical contact conditions.

The arc torch angle greatly affected the deposition characteristics in the wire arc additive manufacturing (WAAM) process, and the relation between the droplet transition behavior and macrostructure morphology was unclear. This work researched the effect of torch angle on the formation accuracy, droplet transition behavior and the mechanical properties in the WAAM process on a ZL205A aluminum alloy. The results suggested that at the obtuse torch angle, part of the energy input was used to heat the existing molten pool, which was optimized for the longer solidification period of the molten pool. Therefore, the greater layer penetration depth at 100° resulted in the improved layer-by-layer combination ability. The obtuse torch angle was associated with the better formation accuracy on the sidewall surface due to the smaller impact on the molten pool, which was influenced by both the arc pressure and droplet impact force. The eliminated pores were optimized for the mechanical properties of depositions at a torch angle of 100°; thus, the tensile strength and elongation attained maximum values of 258.6 MPa and 17.1%, respectively. These aspects made WAAM an attractive mode for manufacturing large structural components on ZL205A aluminum alloy.

The detection of keyhole-induced pore positions is a critical procedure for assessing laser welding quality. Considering the detection error due to pore migration and noise interference, this research proposes a regional prediction model based on the time–frequency-domain features of the laser plume. The original plume signal was separated into several signal segments to construct the morphological sequences. To suppress the mode mixing caused by environmental noise, variational modal decomposition (VMD) was utilized to process the signals. The time–frequency features extracted from the decomposed signals were acquired as the input of a backpropagation (BP) neural network to predict the pore locations. To reduce the prediction error caused by pore migration, the effect of the length of the signal segments on the prediction accuracy was investigated. The results show that the optimal signal segment length was 0.4 mm, with an accuracy of 97.77%. The 0.2 mm signal segments failed to eliminate the negative effects of pore migration. The signal segments over 0.4 mm resulted in prediction errors of small and dense pores. This work provides more guidance for optimizing the feature extraction of welding signals to improve the accuracy of welding defect identification.

ObjectiveThis study offers a bibliometric analysis of the current situation, hotspots, and cutting-edge domains of genetic factors of adolescent idiopathic scoliosis (AIS).MethodsAll publications related to genetic factors of AIS from January 1, 1992, to February 28, 2023, were searched from the Web of Science. CiteSpace software was employed for bibliometric analysis, collecting information about countries, institutions, authors, journals, and keywords of each article.ResultsA cumulative number of 308 articles have been ascertained. Since 2006, publications relating to genetic factors of AIS have significantly increased. China leads in both productivity and influence in this area, with the Chinese Academy of Medical Sciences being the most productive institution. The most prolific scholars in this field are Y. Qiu and Z. Z. Zhu. The publications that contributed the most were from Spine and European Spine Journal. The most prominent keywords in the genetic factors of AIS were “fibrillin gene”, “menarche”, “calmodulin”, “estrogen receptor gene”, “linkage analysis”, “disc degeneration”, “bone mineral density”, “melatonin signaling dysfunction”, “collagen gene”, “mesenchymal stem cell”, “LBX1”, “promoter polymorphism”, “Bone formation”, “cerebrospinal fluid flow” and “extracellular matrix”.ConclusionThis analysis provides the frontiers and trends of genetic factors in AIS, including relevant research, partners, institutions and countries.

Genome miniaturization drives key evolutionary innovations of adaptive traits in vertebrates, such as the flight evolution of birds. However, whether similar evolutionary processes exist in invertebrates remains poorly understood. Derived from the second-largest animal phylum, scallops are a special group of bivalve molluscs and acquire the evolutionary novelty of the swimming lifestyle, providing excellent models for investigating the coordinated genome and lifestyle evolution. Here, we show for the first time that genome sizes of scallops exhibit a generally negative correlation with locomotion activity. To elucidate the co-evolution of genome size and swimming lifestyle, we focus on the Asian moon scallop (Amusium pleuronectes) that possesses the smallest known scallop genome while being among scallops with the highest swimming activity. Whole-genome sequencing of A. pleuronectes reveals highly conserved chromosomal macrosynteny and microsynteny, suggestive of a highly contracted but not degenerated genome. Genome reduction of A. pleuronectes is facilitated by significant inactivation of transposable elements, leading to reduced gene length, elevated expression of genes involved in energy-producing pathways, and decreased copy numbers and expression levels of biomineralization-related genes. Similar evolutionary changes of relevant pathways are also observed for bird genome reduction with flight evolution. The striking mimicry of genome miniaturization underlying the evolution of bird flight and scallop swimming unveils the potentially common, pivotal role of genome size fluctuation in the evolution of novel lifestyles in the animal kingdom.

The Al butt-lap joints are widely applied in China Railway High-speed (CRH) trains body joints. However, the gaps caused by the thermal deformation in Al butt-lap joints lead to the lack penetration or over penetration. To predict the penetration state of laser welds in Al butt-lap joints with different gaps, this work investigated the correlation between the plasma plume morphology and penetration state monitored by high-speed imaging system and the vertical gap and horizontal gap were utilized as intermediary. The ensemble experience mode decomposition (EEMD) was used to obtain the frequency features of plasma plume morphology. A support vector machine (SVM) model combined with EEMD was then established to classify the different penetration state, which adopted the original signals at time-domain and the mode decomposition signals at frequency-domain as input. The EEMD-SVM accuracy of 97.98% was the highest among the EMD-SVM of 86.44% and the SVM of 58.15%. The EEMD-SVM obtained both high Accuracy and Recall when the quantity of positive and negative samples were utmost different. The classification of the EEMD-SVM model was the most superior among the EMD-SVM model and SVM model. This proposed method provided a novel and accurate approach to perform process monitoring and penetration defects detection during laser welding of butt-lap joints.

This paper studies the semi-active suspension damping control algorithm. The shortcomings of traditional damping control algorithms such as the sky-hook algorithm and the acceleration-driven damper algorithms are analyzed in this article. For the shortcomings of the traditional damping control algorithm, a semi-active suspension damping control strategy based on improved particle swarm optimization is proposed. The proposed algorithm uses the dynamic nonlinear inertia coefficient instead of the fixed inertia coefficient of the traditional particle swarm algorithm, which improves solution efficiency and accuracy. Nonlinear damping curves for different forms of expression are optimized using the algorithm, and the optimal nonlinear damping curve for the white noise pavement is obtained. A simulation model is established to verify the effect of the proposed algorithm. The simulation results show that the nonlinear semi-active control strategy can achieve the target of high vibration isolation coefficient at high frequency and strong inhibitory resonance ability at low frequency. Moreover, the jerk of the spring mass does not deteriorate by a large margin. The results show that the nonlinear semi-active control strategy improves the driving comfort of the vehicle.

To overcome the disadvantage of high initial peak crush force (IPCF) in hierarchical and gradient structures, the hierarchical multicellular tubes (HMTs) with gradient character along axial and radial directions are proposed based on the bidirectional structural characters of bamboo stem. Crashworthiness performances of HMTs under oblique loads are systematically studied by using numerical simulation. Results show that compared with the square tube with the same mass, HMTs have higher energy absorption capability under different impact angles. The maximum increases of specific energy absorption (SEA) and crush force efficiency (CFE) reach up to 67.02% and 806%, respectively. Whereas, the maximum decrease of IPCF reaches up to 79.92%. Effects of structural parameters, including hierarchical level, wall thickness and internode space, on the crashworthiness performances of HMTs are also fully investigated.

BackgroundOpinions on the optimal age for surgical management of hydroceles in young boys are not uniform. Scrotal ultrasonography can be used to diagnose hydroceles and measure testicular size. A comparison of bilateral testicular size with hydrocele and the change in trend with age has not been reported. We therefore aimed to analyze the bilateral testicular size of children with unilateral non-communicating hydroceles and examine the correlation between age and testicular volume.MethodsNon-communicating hydrocele cases in children were included. Ultrasound results, age, and diagnose time were retrospectively recorded. The bilateral testicular size was compared, and the correlation between age and testicular volume was analyzed.ResultsThere were 138 cases of non-communicating hydrocele, ranging in age from 11 to 72 months. The diagnose time ranged from 3 days to 54 months. The volume of the testis on the side of the hydrocele was larger than that on the normal side (P < 0.001). Testicular length was not different bilaterally. Testicular width and height were greater on the hydrocele side than on the normal testicular side (PConclusionsAn important finding was that when the contralateral normal testicular volume increases with age, the testicular volume does not increase on the hydrocele side. This finding confirms the adverse effects of hydrocele on testicular growth and provides a basis for early treatment.

ObjectiveTo retrospectively analyze the feasibility and efficacy of posterior hemivertebra resection without internal fixation in the treatment of congenital scoliosis in very young children.MethodsSixteen cases of very young children with congenital scoliosis treated at our hospital from April 2000 to July 2019 were collected, including 8 cases of each sex, all of whom had type I/III congenital scoliosis and were operated on at a median (interquartile range) of 9.00 (7.75) months (range, 0.5–48 months) of age. All cases underwent posterior hemivertebra resection without internal fixation and wore orthopedic braces or plaster undershirts for more than six months after surgery, with a mean follow-up of 94.31 ± 65.63 months (range, 36–222 months).ResultsCoronal plane: the preoperative Cobb angle for the segmental curve was 39.50 ± 9.70° compared to postoperative (19.19 ± 8.56°) and last follow-up (14.94 ± 12.11°) (both P 0.05). There was a tendency for the thoracolumbar kyphosis to worsen and the lumbosacral kyphosis to improve during the follow-up period.ConclusionPosterior hemivertebra resection without internal fixation is a feasible treatment for type I/III congenital scoliosis in very young children, but the correction of the sagittal deformity of the thoracolumbar spine is not satisfactory, and postoperative external fixation may require further improvement.

The present study investigated the influence of energy ratio on microstructure and mechanical properties in the transition zone of hybrid laser-MIG welded 316L/AH36 joints. The region between the laser zone and hybrid zone was defined as the transition zone. The ratio of laser to arc energy was defined as energy ratio. Similar microstructure types including ferrite, austenite, and martensite were observed in the transition zone under each energy ratio. However, obvious difference in microstructure distribution and crystallographic characteristic in transition zone was found in varying energy ratio. With the energy ratio decreasing from 2:1 to 1:2, the fraction of martensite was decreased from 83.1% to 65.6%, the fraction of high angle grain boundaries was increased from 44.8% to 61.3% and the average grain size was increased from 3.62 to 17.20 μm. The phenomenon was attributed to the improvement of cooling rate and reduction of filler metal. Therefore, the highest average microhardness value of 445 HV in the fusion zone was obtained under the highest energy ratio compared to that of 223 HV under the lowest energy ratio. Besides, the low-temperature impact absorption energy was increased from 41 to 90 J and the tensile fracture mode was changed from cleavage fracture mode to ductile fracture mode as the energy ratio decreased from 2:1 to 1:2.

Aiming at the problem of transmission gear idling knocking abnormal noise in a batch of domestically produced new trucks， based on the research method of "conjecture-theoretical research-test verification"， the situation that the transmission idling knocking problem is caused by the friction clutch first-stage torsion damper and mismatch of parameters and power transmission system is analyzed and confirmed. The relationship between the first-stage torsional stiffness， dry friction damping torque， the limit value of the forward and reverse torsion angle and the transmission gear knocking noise is studied. The results show that， the torsion characteristic parameters of the clutch torsion damper can be adjusted to solve the abnormal noise of the transmission idling， which is the simplest and most effective method. Therefore， under the condition that the premise of keeping the first-class forward and reverse torsion angle limit values and dry friction damping torque unchanged， the first-class torsional stiffness is optimized， and the samples are manufactured and tested on the vehicle. The data of speed and noise time domain is collected after optimization of the clutch and is post-processed. Then compared with the before it had not been optimized， and the subjective feelings are compared. Both theoretical analysis and tests show that， the friction clutch after adjusting the first-stage torsional stiffness effectively attenuates the engine output speed fluctuations， and the transmission idling knocking abnormal noise is well suppressed. This method has reference value for solving other similar transmission gear knocking problems.

The work aimed to investigate the effects of alternating magnetic field on the microstructure, mechanical properties and plasma characteristics during laser-MIG hybrid welding of HG785D steel. The weld appearance was improved and the weld depth was significantly enhanced by an alternating magnetic field. The same microstructure type of lath martensite (LM) was obtained in the arc zone and laser zone of all hybrid welded joints. However, grains in the arc zone were significantly refined and the ratio of high-misorientation angles was increased under alternating magnetic field. The average grain size in the arc zone reduced from 4.60 to 3.67 μm with a magnetic flux density of 30 mT. The average microhardness of the arc part and the laser part increased from 356 and 378 to 388 and 393 HV, respectively. The grain refinement and increased ratio of high-misorientation angles led to an improvement in low-temperature impact toughness. The low-temperature impact toughness was 184 J with a magnetic flux density of 30 mT, which was 95.7% higher than that without the alternating magnetic field. Additionally, the shielding effect of the hybrid plasma was suppressed with the magnetic flux density of 10–30 mT, leading to an increase in the penetration ability of hybrid heat sources and weld depth. However, the penetration ability of the hybrid heat source was no longer enhanced with a further increase in magnetic flux density.

Split cord malformation (SCM) is a neural tube defect that the spinal cord is longitudinally separated into two hemicords with individual functions, which causes severe spinal cord impairment and sensorimotor deficit. As a kind of myelodysplasia and a special type of tethered cord syndrome, SCM is not widely understood, and common issues in the diagnosis and treatment of SCM should be clarified. In this paper, the Chinese Split Cord Malformation Working Group made a consensus for SCM on embryopathogenesis and types, clinical presentations, neuroimaging assessment, indications and principle of the surgery, surgical techniques and nuances, and prognosis and follow up.

The hydrolysis of sugar-containing compounds by glycoside hydrolases (GHs) plays essential roles in many major biological processes, but to date our systematic understanding of the functional diversity and evolution of GH families remains largely limited to a few well-studied terrestrial animals. Molluscs represent the largest marine phylum in the animal kingdom, and many of them are herbivorous that utilize algae as a main nutritional source, making them good subjects for studying the functional diversity and adaptive evolution of GH families. In the present study, we conducted genome-wide identification and functional and evolutionary analysis of all GH families across major molluscan lineages. We revealed that the remarkable expansion of the GH9, GH10, GH18 and GH20 families and the wide adoption of carbohydrate-binding modules in molluscan expanded GH families likely contributed to the efficient hydrolysis of marine algal polysaccharides and were involved in the consolidation of molluscan algae-feeding habits. Gene expression and network analysis revealed the hepatopancreas as the main organ for the prominent expression of approximately half of the GH families (well corresponding to the digestive roles of the hepatopancreas) and key or hub GHs in the coexpression gene network with potentially diverse functionalities. We also revealed the evolutionary signs of differential expansion and functional divergence of the GH family, which possibly contributed to lineage-specific adaptation. Systematic analysis of GH families at both genomic and transcriptomic levels provides important clues for understanding the functional divergence and evolution of GH gene families in molluscs in relation to their algae-feeding biology.

Abstract Chondrosarcoma (CS) is a rare cancer, but it is the second most common primary malignant bone tumor and highly resistant to conventional chemotherapy and radiotherapy. Aberrant DNA methylation in the promoter CpG island of Wnt inhibitory factor 1 (WIF1) has been observed in different cancers. However, no studies have shown the relationship between WIF1 methylation and CS. In this study, we found promoter methylated WIF1 in both CS cell lines (CS-1 and SW1353) and tumor tissues. Western blot analysis confirmed loss WIF1 expression and activation of Wnt pathway proteins (Wnt5a/b, LRP6, and Dvl2). We subsequently examined the correlation between levels of WIF1 methylation and overall survival (OS) and progression-free survival (PFS) in CS patient samples with a follow-up spanning 234 months (mean: 57.6 months). Kaplan-Meier survival curves and log-rank tests revealed that high levels of WIF1 methylation were associated with lower OS and PFS rates (p

Strong steering wheel jitter during idling states of the engine can seriously deteriorate the driving comfort as well as the driving safety. The powertrain suspension system can be considered as the only essential path for the transmission of vibrations from the engine to the vehicle cab. Its vibration isolation performance directly affects the severity of vibrations on the steering wheel. In this article, aiming at solving the problem of a certain type of commercial vehicle’s steering wheel with strong idle jitter at the idle state, the intrinsic characteristics and vibration isolation performances of the powertrain suspension system were studied in detail. A multi-sensor-based measurement strategy was utilized to evaluate the idle jitter severity of the steering wheel. In order to improve the indicators of the decoupling degree, the vibration transmissibility, and the resonant frequency distributions of the engine suspension system, an optimization model of engine suspension system was established. Parameters of the optimized suspension system were obtained by multi-objective particle swarm optimization. Finally, the effectiveness and feasibility of the optimization algorithm to solve the problem of the vehicle’s steering wheel jitter at idle states were verified through a test using multiple acceleration sensors, which has practical values in the engineering field.

Spondylus violaceus is a species of the bivalve family Spondylidae, commonly known as thorny oyster. Here, we report the complete mitochondrial genome of S. violaceus. The mitochondrial genome of S. violaceus is 30,160 bp in length, which contains 12 protein-coding genes, 2 ribosomal RNA genes and 19 transfer RNA genes. The overall AT content (58.31%) was higher than GC content (41.69%). This is the first record of complete mitochondrial genome in the family Spondylidae, providing the basis for future taxonomic and phylogenetic studies of this bivalve family.