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To investigate the effects of conventional shot peening and micro-particle shot peening on the surface properties of 42CrMo steel，ABAQUS software was employed to identify the primary and secondary influencing factors of these two processes on material surface roughness and the depth of the residual stress layer through orthogonal experiments.Based on the analysis results of the orthogonal experiments，practical experiments were conducted for validation.Considering the characteristics of micro-particle shot peening and conventional shot peening，a single-factor study of the shot peening coverage rate was carried out to examine the impact of these two processes on the residual stress，surface roughness and equivalent plastic strain of 42CrMo steel.Results showed that under the same coverage rate condition，micro-particle shot peening yielded higher residual compressive stress，lower surface roughness and higher equivalent plastic strain compared to conventional shot peening，accompanied by a slightly shallower strengthening layer.The increase in residual compressive stress contributed to improving wear resistance and fatigue performance of the material，while the lower surface roughness contributed to restraining crack initiation.Higher equivalent plastic strain could further refine grains and promote the generation of residual compressive stress.These advantages suggested the broad prospects of micro-particle shot peening in the surface strengthening of mechanical components.

In order to avoid the blindness of the hydraulic fracturing of the directional long borehole in coal mine 2130 of Xinjiang Coking Coal Group, and to accurately grasp the extension and expansion of hydraulic fracturing under different hole layout methods, this paper uses the numerical simulation method to carry out hydraulic fracturing numerical simulation for comb directional long borehole in 4# coal seam of coal mine 2130 with a buried depth of 500 m. The simulation results show that the different hole layout methods have obvious effects on hydraulic fracturing initiation pressure, crack initiation position, fracture mode and crack extension and expansion law, combined with the actual situation of 4# coal seam in coal mine 2130, the optimal drilling hole layout method and fracturing parameters are optimized for engineering practice, and good fracturing results have been achieved. Compared with the previous hydraulic fracturing measures at this level, the drainage concentration is increased by 2.7 times, and the scalar amount of drainage increased by 11.8 times.

BackgroundThe SXFEL (Soft X-ray Free-Electron Laser facility) is the first X-ray coherent light source in China. To monitor the beam loss in its undulator beamline, a quartz fiber beam loss monitoring system based on the Cherenkov radiation principle was designed and installed. The quartz fiber is insensitive to high-energy gamma rays, making it suitable for a strong SXFEL radiation field environment.PurposeThis study aims to apply quartz fiber beam loss monitoring (BLM) system to the undulator beamline of SXFEL, and carry out position calibration experiment to measure the fiber attenuation coefficient, and performance of the system in the beam tuning period.MethodsFirst, two pure quartz composition fibers with 400 μm inner diameter of core and high concentration of hydroxide ions were employed. The beam loss signal was generated by falling YAG (Ce:Y3Al5O12, target film) of the beam profile monitor at a fixed position and adjusting the trigger time delay to make the position of the beam loss signal the same as that of the beam profile monitor for position calibration experiment. Second, to measure the fiber attenuation coefficient, the coefficient was fitted by bringing the peak value of the beam loss signal generated by the falling YAG at different positions of the SBP (Shanghai-XFEL Beamline Project) beamline and the corresponding fiber position into the signal attenuation formula.ResultsThe fiber BLM can accurately reflect the position of the beam loss with upstream position resolution of approximate 0.2 m in the experiment test, as well as in the period of beam tuning. The refractive index of quazrtz firber core is approximately 1.5, hence the relationship between the beam loss position and signal arrival to upstream PMT time interval is 0.12 m·ns-1. The measured fiber attenuation coefficient is around 74 dB·km-1, which is consistent with the calculation result and similar to the measurement result of SPring-8 Angstrom Compact Free Electron Laser (SACLA) using the same type of optical fiber.ConclusionsThe fiber beam loss monitoring system has a good position resolution and has the potential to meet the requirements of SXFEL beam tuning.

The chemical composition and fracture toughness of thermal barrier coatings (TBCs) before and after heat treatment were characterized, and the cracks around the interface between the coating and the substrate could be successfully eliminated and meanwhile the porosity of the coatings tended to reduce. The XRD analysis revealed the coatings were composed of non-transformable tetragonal t’ phase of ZrO2 and γ $\gamma $-(Ni, Cr) with minor Ni3Al (γ′ $\gamma ^' $) precipitates. Additionally, the relationship between the heat treatment and wear resistance was systematically studied. The results indicated that both the hardness and fracture toughness increased after quenching process. The oxidation wear became more prominent after heat treatment, which probably resulted from the better bonding strength of coatings. Dense and homogeneous microstructure introduced by vacuum oil-quenching improved stabilization of the weight gain during thermal cycle test.

Epilepsy is a neurological disorder characterized by recurrent seizures, which can affect individuals of all age groups, but infants and older individuals are particularly vulnerable. Sudden epileptic attacks can pose significant risks and be life-threatening, impacting the overall quality of life of affected individuals. With the progress made in medical science, Electroencephalography (EEG) has emerged as a valuable tool for diagnosing and predicting seizure occurrences. The availability of wearable EEG devices, including caps and helmets, has become increasingly prominent in the market. As a result, there has been a recent surge in the development of deep learning-based systems. These systems are helpful for diagnosis in hospital settings and for mobile applications that provide timely warnings and predictions regarding seizure onset. Most of the existing state-of-the-art (SOTA) approaches focus on distinguishing between healthy and epileptic patients. Some studies categorize individuals into three classes: healthy, experiencing the onset of a seizure, or currently having a seizure, specifically focusing on mobile applications. However, limited literature is available on the five-class problem, which is valuable for localization and diagnosis in hospitals and mobile applications. In this regard, we propose our novel model, named EpilConNet, and conduct extensive experiments on a real-world dataset to demonstrate its efficacy in all modes of classification. EpilConNet results in a significant increase of 4% in accuracy in five-class classification. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the Hodgkin–Huxley theory, this paper establishes several nonlinear system models, analyzes the models' stability, and studies the conditions for repetitive discharge of neuronal membrane potential. Our dynamic analysis showed that the main channel currents (the fast transient sodium current, the potassium delayed rectifier current, and the fixed leak current) of a neuron determine its dynamic properties and that the GHK formula will greatly widen the stimulation current range of the repetitive discharge condition compared with the Nernst equation. The model including the change in ion concentration will lead to spreading depression (SD)-like depolarization, and the inclusion of a Na-K pump will weaken the current stimulation effect by decreasing the extracellular K accumulation. The results indicate that the Hodgkin–Huxley model is suitable for describing the response to initial stimuli, but due to changes in ion concentration, it is not suitable for describing the response to long-term stimuli. [ABSTRACT FROM AUTHOR]

Doping with oxygen and nitrogen in graphite felt (GF) is critical for enhancing the activity of the electrode material in vanadium redox flow batteries (VRFB). In this paper, we present a combined approach that utilizes Fe etching and nitrogen functionalization by means of K2FeO4 and NH3 to modify the surface structure of graphite fibers. The results show that the innovative approach enhances the disordered structure of the surface carbon of GF and substantially improves the oxygen and nitrogen functionalized groups. This modified GF is completely hydrophilic, and its assembled electrode energy efficiency is 80.08% at a current density of 80 mA∙cm−2, compared with 69.87% for the pristine GF. The energy efficiency of the modified GF was maintained at 81.8% after 50 charge-discharge cycles. This can be attributed to the reduced internal resistance of these modified GF electrode as well as to the improved mass transport and charge redox exchange towards VO2+/VO2+ redox couple. The combined approach of Fe etching and nitrogen functionalization significantly enhances the electrochemical activity of the GF electrode. This improves the performance of the VRFB. [ABSTRACT FROM AUTHOR]

Copyright of Geology & Exploration is the property of Geology & Exploration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geology & Exploration is the property of Geology & Exploration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Benzylisoquinoline alkaloids (BIAs) are a type of secondary metabolite with clinical application value. (S)-stylopine is a special BIA which contains methylenedioxy bridge structures. CYP719As could catalyze the methylenedioxy bridge-formation on the A or D rings of protoberberine alkaloids, while displaying significant substrate regiospecificity. To explore the substrate preference of CYP719As, we cloned and identified five CyCYP719A candidates from Corydalis yanhusuo. Two CyCYP719As (CyCYP719A39 and CyCYP719A42) with high catalytic efficiency for the methylenedioxy bridge-formation on the D or A rings were characterized, respectively. The residues (Leu 294 for CyCYP719A42 and Asp 289 for CyCYP719A39) were identified as the key to controlling the regioselectivity of CYP719As affecting the methylenedioxy bridge-formation on the A or D rings by homology modeling and mutation analysis. Furthermore, for de novo production of BIAs, CyCYP719A39, CyCYP719A42, and their mutants were introduced into the (S)-scoulerine-producing yeast to produce 32 mg/L (S)-stylopine. These results lay a foundation for understanding the structure-function relationship of CYP719A-mediated methylenedioxy bridge-formation and provide yeast strains for the BIAs production by synthetic biology. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Double-shield TBM is more efficient than shield tunnel construction in hard rock strata. It is widely used in subway tunnel construction, such as in Qingdao and Chongqing in China. However, construction vibration problems caused by double-shield TBM critically affect human comfort in surface buildings. In order to study the vibration influence law of double-shield TBM, the on-site monitoring plan of double-shield TBM is developed, relying on a tunnel section of Qingdao Metro Line 4. Then, the vibration monitoring results are analyzed, and the time domain and frequency domain characteristics of vibration acceleration are obtained. Subsequently, taking vibration peak acceleration as the research object, the transverse and longitudinal vibration laws of double-shield TBM construction are studied. Finally, according to the standard of human comfort in buildings, the vibration influence ranges of double-shield TBM construction are obtained. The research results can provide a reference for the vibration effect of double-shield TBM passing through houses, highways and bridges. Moreover, it can also provide a basis for the disputes that double-shield TBM tunnel construction affects the lives of inhabitants. [ABSTRACT FROM AUTHOR]

The Chinese soft‐shelled turtle, Pelodiscus sinensis, is an important aquaculture species in China. Understanding the molecular mechanisms of growth regulation may contribute to its genetic improvement and lead to increases in the production. Growth rate in this species varies greatly among individuals, and the variation apparently has a genetic basis. To identify growth‐related genes and explore the molecular mechanism of its growth regulation, fast‐growing and slow‐growing turtles were selected from two growth stages, juveniles or adults, respectively, for transcriptome sequencing with liver tissue using the Illumina sequencing platform. Analyses showed that, in juveniles, 303 genes were differentially expressed, of which 217 genes were expressed at higher levels in the fast‐growing turtles. In adults, 1,093 genes were differentially expressed, of which 682 genes were expressed at higher levels in the fast‐growing turtles. Gene Ontology (GO) enrichment of differentially expressed genes (DEGs) identifies three functional groups being significantly enriched in juveniles, but 71 functional groups in adults. Kyoto Encyclopedia of Genes and Genomes enrichment analysis of DEGs in juveniles identified only one pathway being significantly enriched, the proxisome proliferator‐activated receptor (PPAR) signaling pathway, while eight pathways mostly related to fatty acid metabolism were identified in adults. These findings suggest that regulation of growth is more complicated and involves more genes and pathways in adults compared with juveniles, and metabolic or metabolic‐related genes may relate to the growth difference of P. sinensis. Some key genes related to growth were identified from another six growth‐related signaling pathways, and DEGs in GH‐IGF 1 axis genes and Jak–STAT signaling pathway might play important roles in the growth difference of P. sinensis. In addition, 73 single‐nucleotide polymorphisms (SNPs) from 23 growth‐related genes were successfully genotyped. Growth association analysis in 280 individuals revealed that 2 SNPs in 2 key genes (IGF2R and SLC27A2) were associated with growth of P. sinensis. This study provides information on key genes, SNPs, and biological processes that may be involved in growth and highlights the differentiation of growth regulation in different growth stages of P. sinensis. [ABSTRACT FROM AUTHOR]

The rapid development of urbanization has had a dramatic impact on the economy, society and environment in China. In this context, the coordination relationship between population urbanization and land urbanization is essential for achieving sustainable urbanization. Based on the statistical data from 2007–2017 in the Yangtze River Economic Belt (YEB), this paper established the multi-dimensional coordination evaluation (MDCE) model by using the speed coordination evaluation (SCE) model, the level consistency evaluation (LCE) model, the entropy method and the space matching evaluation (SME) model to evaluate the coordination relationship between population urbanization and land urbanization from the speed-level-space perspective. The results showed that from 2007 to 2017: 1) the development speed of population urbanization and land urbanization in the YEB were more and more coordinated, and the speed of population urbanization lagged behind that of land urbanization. In addition, the overall development speed of the 11 provinces declined, and most of them were characterized by excessive development of land urbanization. 2) the development level of population urbanization and land urbanization in the YEB were all high, but the development level of population urbanization was lower than that of land urbanization. Further, the development level of the 11 provinces remained stable and high, and continuously improved. 3) the space matching of population urbanization and land urbanization in the YEB had a high degree of coordination, and the space matching degree of population urbanization was higher than that of land urbanization. Moreover, the space matching of most provinces in the region had declined, but the change was small. Finally, this paper proposes the policy recommendations on the coordinated development of population and land urbanization at the institutional, market and management levels to achieve coordinated and sustainable urbanization. [ABSTRACT FROM AUTHOR]

Thermal treatment is a widely applied food processing technology in the meat industry due to its convenience. However, the interpretation of the changes in the bacterial community and quality properties in the thermal processed meat products have not been well established. Therefore, the effects of thermal treatment on the quality characteristics and bacterial communities in meatballs during storage at 4°C were investigated, which will provide a more comprehensive understanding of the influence of thermal treatment on the meat quality. Thermal treatment (121°C, 15 min) decreased the initial total viable bacterial counts by 2.1 log CFU/g and the diversity of the initial bacterial communities in meatballs. Compared with the thermal treatment group, a significantly more rapidly increasing trend of total volatile basic nitrogen and a decreasing trend of pH were observed in the control group. At the end of storage, the bacterial community was dominated by Streptococcus, Acinetobacter and Pseudomonas in the thermal treatment meatballs, whereas Pseudomonas, Pantoea, and Serratia. dominated the bacterial community of the control group. Besides, the predicted metabolic pathways revealed high levels of carbohydrate, amino acid, and lipid metabolism in the control group. This finding could contribute to a deep understanding of the influence of thermal treatment on the meat quality. Moreover, these results could provide a theoretical foundation for the development of alternative and novel nonthermal processing technologies for use in the meat industry. [ABSTRACT FROM AUTHOR]

To decode the pilot's behavioral awareness, an experiment is designed to use an aircraft simulator obtaining the pilot's physiological behavior data. Existing pilot behavior studies such as behavior modeling methods based on domain experts and behavior modeling methods based on knowledge discovery do not proceed from the characteristics of the pilots themselves. The experiment starts directly from the multimodal physiological characteristics to explore pilots' behavior. Electroencephalography, electrocardiogram, and eye movement were recorded simultaneously. Extracted multimodal features of ground missions, air missions, and cruise mission were trained to generate support vector machine behavior model based on supervised learning. The results showed that different behaviors affects different multiple rhythm features, which are power spectra of the 𝜃 waves of EEG, standard deviation of normal to normal, root mean square of standard deviation and average gaze duration. The different physiological characteristics of the pilots could also be distinguished using an SVM model. Therefore, the multimodal physiological data can contribute to future research on the behavior activities of pilots. The result can be used to design and improve pilot training programs and automation interfaces. [ABSTRACT FROM AUTHOR]

Establishment of the primordial follicle (PF) pool is pivotal for the female reproductive lifespan; however, the mechanism of primordial folliculogenesis is poorly understood. Here, the transcription factor SP1 was shown to be essential for PF formation in mice. Our results showed that SP1 is present in both oocytes and somatic cells during PF formation in the ovary. Knockdown of Sp1 expression, especially in pregranulosa cells, significantly suppressed nest breakdown, oocyte apoptosis, and PF formation, suggesting that SP1 expressed by somatic cells functions in the process of primordial folliculogenesis. We further demonstrated that SP1 governs the recruitment and maintenance of Forkhead box L2-positive (FOXL2+) pregranulosa cells using an Lgr5 -EGFP-IRES- Cre ERT2 (Lgr5 - KI) reporter mouse model and a FOXL2+ cell-specific knockdown model. At the molecular level, SP1 functioned mainly through manipulation of NOTCH2 expression by binding directly to the promoter of the Notch2 gene. Finally, consistent with the critical role of granulosa cells in follicle survival in vitro , massive loss of oocytes in Sp1 knockdown ovaries was evidenced before puberty after the ovaries were transplanted under the renal capsules. Conclusively, our results reveal that SP1 controls the establishment of the ovarian reserve by regulating pregranulosa cell development in the mammalian ovary. [ABSTRACT FROM AUTHOR]

In the automatic detection of epileptic seizures, the monitoring of critically ill patients with time varying EEG signals is an essential procedure in intensive care units. There is an increasing interest in using EEG analysis to detect seizure, and in this study we aim to get a better understanding of how to visualize the information in the EEG time-frequency feature, and design and train a novel random forest algorithm for EEG decoding, especially for multiple-levels of illness. Here, we propose an automatic detection framework for epileptic seizure based on multiple time-frequency analysis approaches; it involves a novel random forest model combined with grid search optimization. The short-time Fourier transformation visualizes seizure features after normalization. The dimensionality of features is reduced through principal component analysis before feeding them into the classification model. The training parameters are optimized using grid search optimization to improve detection performance and diagnostic accuracy by in the recognition of three different levels epileptic of conditions (healthy subjects, seizure-free intervals, seizure activity). Our proposed model was used to classify 500 samples of raw EEG data, and multiple cross-validations were adopted to boost the modeling accuracy. Experimental results were evaluated by an accuracy, a confusion matrix, a receiver operating characteristic curve, and an area under the curve. The evaluations indicated that our model achieved the more effective classification than some previous typical methods. Such a scheme for computer-assisted clinical diagnosis of seizures has a potential guiding significance, which not only relieves the suffering of patient with epilepsy to improve quality of life, but also helps neurologists reduce their workload. [ABSTRACT FROM AUTHOR]

Technology of brain-computer interface (BCI) provides a new way of communication and control without language or physical action. Brain signal tracking and positioning is the basis of BCI research, while brain modeling affects the treatment analysis of (EEG) and functional magnetic resonance imaging (fMRI) directly. This paper proposes human ellipsoid brain modeling method. Then, we use non-parametric spectral estimation method of time-frequency analysis to deal with simulation and real EEG of epilepsy patients, which utilizes both the high spatial and the high time resolution to improve the doctor's diagnostic efficiency. [ABSTRACT FROM AUTHOR]

Abstract: This study assessed the influence of stewing (1, 2 or 3 h) on the texture, ultrastructure and in vitro digestibility of meat from the yellow‐feathered chicken, which is a popular broiler chicken in Asia. Results indicated that longer stewing considerably increased cooking loss of the chicken carcass and tenderness of thigh meat. After 3 h of stewing, protein digestibility decreased from 90.5% to 80.3% and fiber diameter decreased by 8.63 μm. The shear force value of breast meat decreased from 32.34 N at 1 h to 10.29 N at 2 h, and then increased to 39.98 N at 3 h. The texture profile of breast meat remarkably decreased during stewing. Moreover, increased stewing time induced longitudinal and transversal shrinkage of muscle fibers and the degradation of the myosin heavy chain. These findings suggested that prolonged stewing (3 h) resulted in decreased meat qualities, based on the changes in cooking loss, digestibility and texture profile, but that stewing for 2 h increased thigh and breast tenderness. Producers could utilize this information to stew yellow‐feathered chicken meat with desirable qualities. [ABSTRACT FROM AUTHOR]

Nano-scaled materials have been proved to be ideal DNA carriers for transgene. Bacterial magnetic particles (BMPs) help to reduce the toxicity of polyethylenimine (PEI), an efficient gene-transferring agent, and assist tissue transgeneex vivo. Here, the effectiveness of the BMP-PEI complex-conjugated foreign DNAs (BPDs) in promoting testes-mediated gene transfer (TMGT) in mouse was compared with that of liposome-conjugated foreign DNAs. The results proved that through testes injection, the clusters of BPDs successfully reached the cytoplasm and the nuclear of spermatogenesis cell, and expressed in testes of transgene founder mice. Additionally, the ratio of founder mice obtained from BPDs (88%) is about 3 times higher than the control (25%) (p < 0.05). Interestingly, the motility of sperms recovered from epididymis of the founder mice from BPD group were significantly improved, as compared with the control (p < 0.01). Based on classic breeding, the ratio of transgene mice within the first filial was significantly higher in BPDs compared with the control (73.8% versus 11.6%,p < 0.05). TMGT in this study did not produce visible histological changes in the testis. In conclusion, nano-scaled BPDs could be an alternative strategy for efficiently producing transgene micein vivo. [ABSTRACT FROM AUTHOR]