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The growth of lithospheric thickness beneath the Tibetan Plateau since Early Cretaceous is demonstrated by changes in partial melting depth of the mantle as reflected in the Ce/Yb and Sm/Yb ratios ...

The synthesis of sulfochromeno [4,3-b] pyrrolidines is described. Under the catalysis of 20 mol% Brønsted base and using 4Å molecular sieves as HF scavenger, imines derived from salicylaldehydes and diethyl aminomalonate react with ethenesulfonyl fluorides through a tandem [3+2] cyclization-SuFEx click reaction to produce sulfochromeno [4,3-b] pyrrolidines in high yields.

A tandem annulation reaction of allyl ketones and ethenesulfonyl fluoride has been described. Under the catalysis of Brønsted base, vinyl ketones reacted with ethenesulfonyl fluoride through a cascade intermolecular Michael addition-intramolecular SuFEx process to afford γ-alkenylated δ-sultones in good to excellent reaction yields. In this reaction, no additional base was needed, and 4 Å Molecular sieves was used as efficient HF scavenger to restrict the neutralization and deactivation of the Brønsted base catalyst.

Existing model-based value expansion (MVE) methods typically leverage a world model for value estimation with a fixed rollout horizon to assist policy learning. However, a proper horizon setting is essential to world-model-based policy learning. Meanwhile, choosing an appropriate horizon value is time-consuming, especially for visual control tasks. In this article, we investigate the idea of adaptively using the model knowledge for value expansion. We propose a novel world-model-based method called dynamic-horizon MVE (DMVE) to adjust the use of the world model with adaptive rollout horizon selection. Based on the reconstruction-based technique, the raw and reconstructed images are both used to obtain multihorizon rollouts by utilizing latent imagination. Then, a horizon reliability degree detection approach is given to select appropriate horizons and obtain more accurate value estimation by the reconstructed value expansion errors. Experimental results on the mainstream benchmark visual control tasks show that DMVE outperforms all baselines in sample efficiency and final performance. In addition, experiments on the autonomous driving lane-changing task further demonstrate the scalability of our method. The codes of DMVE are available at https://github.com/JunjieWang95/dmve.

Based on social exchange and broaden-and-build of positive emotions theory, this study examines the effect of perceived corporate social responsibility on employee voice behavior and the mediating role of felt obligation and positive emotions on this relationship. Data collected from 276 employees working in China organizations. The findings revealed that perceived corporate social responsibility affects employee voice behavior. Moreover, both felt obligation and positive emotions mediate the relationship between perceived corporate social responsibility and employee voice behavior. Finally, the theoretical and managerial implications are further discussed in light of these findings.

In this paper, we develop a novel non-parametric online actor-critic reinforcement learning (RL) algorithm to solve optimal regulation problems for a class of continuous-time affine nonlinear dynamical systems. To deal with the value function approximation (VFA) with inherent nonlinear and unknown structure, a reproducing kernel Hilbert space (RKHS)-based kernelized method is designed through online sparsification, where the dictionary size is fixed and consists of updated elements. In addition, the linear independence check condition, i.e., an online criteria, is designed to determine whether the online data should be inserted into the dictionary. The RHKS-based kernelized VFA has a variable structure in accordance with the online data collection, which is different from classical parametric VFA methods with a fixed structure. Furthermore, we develop a sparse online kernelized actor-critic learning RL method to learn the unknown optimal value function and the optimal control policy in an adaptive fashion. The convergence of the presented kernelized actor-critic learning method to the optimum is provided. The boundedness of the closed-loop signals during the online learning phase can be guaranteed. Finally, a simulation example is conducted to demonstrate the effectiveness of the presented kernelized actor-critic learning algorithm.

The supra-subduction zone ophiolite or ophiolitic mélange formed in the forearc setting is generally considered to be a key geological record for subduction initiation (SI) with petrological characteristics comparable to the SI-related rock sequence from forearc basalt (FAB) to boninite in the Izu-Bonin-Mariana subduction zone. Nevertheless, the standard FAB and boninite are generally difficult to observe in the forearc rocks generated during SI. Yet, a typical rock sequence indicating the SI of the western Proto-Tethys Ocean is reported for the first time in the Qimanyute intra-oceanic forearc system in the western Kunlun Orogen, Northwest Tibetan Plateau. The magmatic compositions, which range from less to more high field strength element (HFSE)-depleted and large ion lithophile element (LILE)-enriched, are changing from oceanic plagiogranites (ca. 494 Ma) to forearc basalt-like gabbros (FAB-Gs, ca. 487 Ma), boninites, and subsequent Nb-enriched gabbros (NEGs, ca. 485 Ma), which are thus consistent with the Izu-Bonin-Mariana forearc rocks as well as the Troodos and Semail supra-subduction zone-type ophiolites. The geochemical data from the chemostratigraphic succession indicate a subduction initiation process from a depleted mid-oceanic-ridge (MORB)-type mantle source with no detectable subduction input to gradual increasing involvement of subduction-derived materials (fluid/melts and sediments). The new petrological, geochemical, and geochronological data, combined with the regional geology, indicate that the well-sustained FAB-like intrusive magmas with associated boninites could provide crucial evidence for SI and further reveal that the SI of the western Proto-Tethys Ocean occurred in the Late Cambrian (494–485 Ma).

Studying the microbial symbionts of eukaryotic hosts has revealed a range of interactions that benefit host biology. Most eukaryotes are also infected by parasites that adversely affect host biology for their own benefit. However, it is largely unclear whether the ability of parasites to develop in hosts also depends on host-associated symbionts, e.g., the gut microbiota. Here, we studied the parasitic wasp Leptopilina boulardi (Lb) and its host Drosophila melanogaster. Results showed that Lb successfully develops in conventional hosts (CN) with a gut microbiota but fails to develop in axenic hosts (AX) without a gut microbiota. We determined that developing Lb larvae consume fat body cells that store lipids. We also determined that much larger amounts of lipid accumulate in fat body cells of parasitized CN hosts than parasitized AX hosts. CN hosts parasitized by Lb exhibited large increases in the abundance of the bacterium Acetobacter pomorum in the gut, but did not affect the abundance of Lactobacillus fructivorans which is another common member of the host gut microbiota. However, AX hosts inoculated with A. pomorum and/or L. fructivorans did not rescue development of Lb. In contrast, AX larvae inoculated with A. pomorum plus other identified gut community members including a Bacillus sp. substantially rescued Lb development. Rescue was further associated with increased lipid accumulation in host fat body cells. Insulin-like peptides increased in brain neurosecretory cells of parasitized CN larvae. Lipid accumulation in the fat body of CN hosts was further associated with reduced Bmm lipase activity mediated by insulin/insulin-like growth factor signaling (IIS). Altogether, our results identify a previously unknown role for the gut microbiota in defining host permissiveness for a parasite. Our findings also identify a new paradigm for parasite manipulation of host metabolism that depends on insulin signaling and the gut microbiota.

Block copolymer polymersomes offer considerable access for applications in a variety of fields; however, the traditional cosolvent self-assembly method can only produce polymersomes at a low solids...

Recent advances in artificial intelligence, big data, mobile edge computing and embedded systems have successfully driven the emergence and adoption of smart vehicles and vehicle edge computing which will improve road safety, traffic congestions, and vehicle exhaust emissions. The high-mobility, ad-hoc network topology, and diverse vehicle-to-everything (V2X) have brought substantial challenges in the TCP/IP-based vehicular networking. Given the unique characteristics and strengths in resilient communication in mobile ad hoc networking environments, named data networking (NDN) has become a natural fit for supporting vehicular edge computing (VEC) as the underlying network architecture. However, a variety of security and privacy challenges remain for developing NDN-based VEC networks such as key management, cache poisoning, access control. In this paper, we introduce a novel blockchain-based security architecture in NDN-based VEC networks to systematically tackle these security challenges. More specifically, we design and implement an efficient blockchain system on NDN by adopting lightweight yet robust delegate consensus algorithm, and carry out extensive experiments to evaluate performance efficiency on key management protocols, cache poisoning defense schemes, and access control strategies for NDN-based VEC networks. To the best of our knowledge, this paper is the first effort to systematically devise practical and efficient blockchain-based security architecture to provide key management, cache poisoning security protection, and privacy-aware access control in NDN VEC networks.

The corrosion behaviour of high-strength low-alloy AISI 4135 steel was studied in the presence of homoacetogenic bacteria (Blautia coccoides GA-1), which catalyse the formation of acetate from H-2 plus CO2 in their energy metabolism. In addition, the effects of cathodic protection were studied. The chronoamperometry curves showed a negative current density. The minimum current density was approximately -1.5 mu A.cm(-2). The results revealed that the strain GA-1 could consume 'cathodic hydrogen' and promote the cathodic reaction of AISI 4135 steel, but the hydrogen consumption of strain GA-1 was not the main reason leading to the increase in the corrosion current density.

Substantial efforts have been undertaken to explore nonzero-sum differential games. Most of these studies are devoted to devising algorithms to pursue Nash equilibrium, where all players with the same access to information will take policies synchronously. However, when it comes to hierarchical optimization and asymmetric information, Nash equilibrium is ineffective. The Stackelberg game provides us with an idea of leader-follower strategy to cope with this conundrum. The paper investigates hierarchical optimal control for continuous-time two-player input-affine systems characterized by nonlinear dynamics and quadratic cost functions. By introducing new costates, this optimization problem is formulated as a Stackelberg game in conjunction with a parametric optimization problem. Besides, the closed-loop information is available for both players. An adaptive learning algorithm is thus developed to approximately obtain the open-loop Stackelberg equilibrium while ensuring the uniform ultimate bounded stability of this closed-loop system, and two approximators structured by neural networks put this purpose into practice. Finally, two numerical examples illustrate that the proposed methodology can accurately obtain optimal solutions, and a comparative example illustrates its characteristics. (C) 2020 Elsevier Inc. All rights reserved.

The hydrogen permeation current increase was noticed for carbon steel in 0.5 mol/L NaCl solution under strong anodic potentials, which is contrary to the common understanding. Hydrogen permeation under cathodic potentials has been widely studied because of possible hydrogen embrittlement failures of high strength steels in seawater, but investigations of anodic polarization on hydrogen permeation are fairly rare, as the hydrogen evolution reaction shall be retarded. To corroborate the observed phenomenon, experiments were conducted using both as-received and vacuum-annealed sheet specimens. It was verified that the observed phenomena originated from the released hydrogen in traps by metal dissolution under anodic polarization.

In order to solve the problem that the importance of the user’s attribute is seldom considered in the most of the existing attribute-based encryption schemes with traitor tracing, we designed a traceable and weighted attribute-based encryption scheme. In our constructed scheme, the private key of the user consisting of user’s identity information is applied to trace traitors. In addition, the idea of weighted attribute is introduced, and the attributes set is transformed into the segmentation set of weighted attributes through the attributes set segmentation algorithm. Via employing a linear secret sharing scheme, the constructed scheme offers fine-grained and nimble access control mechanism. Under the assumption of q-BDHE in the standard model, we prove that the designed scheme is able to reach security against chosen-plaintext attack. By comparing with other relevant schemes, it has significant improvement in the costs of communication and computation, and it is more suitable for the application of the mobile terminal in cloud computing.

Doxorubicin (DOX) is used as a first-line chemotherapeutic drug, whereas dihydroartemisinin (DHA) also shows a certain degree of antitumor activity. Disulfide bonds (-SS-) in prodrug molecules can be degraded in highly reducing environments. Thus, heterodimer prodrugs of DOX and DHA linked by a disulfide bond was designed and subsequently prepared as reduction-responsive self-assembled nanoparticles (DOX-SS-DHA NPs). In an in vitro release study, DOX-SS-DHA NPs exhibited reduction-responsive activity. Upon cellular evaluation, DOX-SS-DHA NPs were found to have better selectivity toward tumor cells and less cytotoxicity to normal cells. Compared to free DiR, DOX-SS-DHA NPs showed improved accumulation at the tumor site and even had a longer clearance half-life. More importantly, DOX-SS-DHA NPs possessed a much higher tumor inhibition efficacy than DOX-sol and MIX-sol in 4T1 tumor-bearing mice. Our results suggested the superior antitumor efficacy of DOX-SS-DHA NPs with less cytotoxicity.

Background Emerging evidence suggests that circular RNAs (circRNAs) were aberrantly expressed in the patients of non-small cell lung cancer (NSCLC). This study aims to evaluate the diagnostic value of potential serum biomarker in circRNAs. Methods Serum circRNAs were extracted and purified by RNA isolated kit and identified by quantitative real time-polymerase chain reaction (qRT-PCR) assay. We then performed a receiver operating characteristic (ROC) curve to estimate the diagnostic efficacy. The relationship between circRNA and clinic characteristics of patients was analyzed by SPSS 25.0. Univariate and multivariate analyses were also used to evaluate its diagnostic capability. The mechanism of circFOXP1 was further excavated by bioinformatics analysis. Results By performing qRT-PCR assay, we identified that circFOXP1 (hsa_circ_0008234) and conventional tumor markers (carcinoembryonic antigen (CEA) and cytokeratin fragment 21–1 (CYFRA21-1)) were all significantly overexpressed in the serum of patients with NSCLC when compared with healthy controls ( P Conclusion Our results highlight the preferable diagnostic potential of serum circFOXP1 in NSCLC.

Hyccin/FAM126A mutations are linked to hypomyelination and congenital cataract disease (HCC), but whether and how Hyccin/FAM126A deficiency causes hypomyelination remains undetermined. This study shows Hyccin/FAM126A expression was necessary for the expression of other components of the PI4KIIIα complex in Drosophila. Knockdown of Hyccin/FAM126A in glia reduced the enrichment of glial cells, disrupted axonal sheaths and visual ability in the visual system, and these defects could be fully rescued by overexpressing either human FAM126A or FAM126B, and partially rescued by overexpressing a plasma membrane-targeting recombinant mouse PI4KIIIα. Additionally, PI4KIIIα knockdown in glia phenocopied Hyccin/FAM126A knockdown, and this was partially rescued by overexpressing the recombinant PI4KIIIα, but not human FAM126A or FAM126B. This study establishes an animal model of HCC and indicates that Hyccin/FAM126A plays an essential role in glial enrichment and axonal sheath in a cell-autonomous manner in the visual system via controlling the expression and stabilization of the PI4KIIIα complex at the plasma membrane.

Background: DNA methylation is an important epigenetic modification, which plays an important role in regulating gene expression at the transcriptional level. In tumor research, it has been found that the change of DNA methylation leads to the abnormality of gene structure and function, which can provide early warning for tumorigenesis. Our study aims to explore the relationship between the occurrence and development of tumor and the level of DNA methylation. Moreover, this study will provide a set of prognostic biomarkers, which can more accurately predict the survival and health of patients after treatment.Methods: Datasets of bladder cancer patients and control samples were collected from TCGA database, differential analysis was employed to obtain genes with differential DNA methylation levels between tumor samples and normal samples. Then the protein-protein interaction network was constructed, and the potential tumor markers were further obtained by extracting Hub genes from subnet. Cox proportional hazard regression model and survival analysis were used to construct the prognostic model and screen out the prognostic markers of bladder cancer, so as to provide reference for tumor prognosis monitoring and improvement of treatment plan.Results: In this study, we found that DNA methylation was indeed related with the occurrence of bladder cancer. Genes with differential DNA methylation could serve as potential biomarkers for bladder cancer. Through univariate and multivariate Cox proportional hazard regression analysis, we concluded that FASLG and PRKCZ can be used as prognostic biomarkers for bladder cancer. Patients can be classified into high or low risk group by using this two-gene prognostic model. By detecting the methylation status of these genes, we can evaluate the survival of patients.Conclusion: The analysis in our study indicates that the methylation status of tumor-related genes can be used as prognostic biomarkers of bladder cancer.

In recent years, convolutional neural network (CNN) has been widely used in security, autonomous driving, and healthcare. Even though CNN has achieved a great performance, the results produced by CNN are difficult to explain and sometimes irresponsible. The black-box nature of CNN makes it lack trust. In this paper, we propose an attention based CNN structure, named IA -CNN, which highly improves the interpretability of the CNN models. Each feature map of the last conv-layer only has one response (one key point) of the target object, which is directly connected to the output. We also combine the attention mechanism to weakly supervise the last conv-layer. In this way, our model can clearly show that which features the model extracted are the keys to the output prediction. Meanwhile, our IA-CNN structure can be used in various classical models with higher performance in the fine-grained classification and comparative performance in the ordinary classification task. Note that our IA-CNN structure is an end-to-end model, the last conv-layer of which can extract key points from images automatically and is connected to the output prediction linearly.

Although the rapid development of high-speed rail (HSR) enhanced the national transportation and boosted the economical grow in China, it also has great impacts on the psychology and behaviors of h...

As job insecurity becomes increasingly common, seeking its palliatives has become a hot topic for scholars, especially for high-speed railway drivers who are vital for the development of China’s high-speed railway. Researches have demonstrated that, organizational support is a valuable psychosocial resource that can alleviate individual negative behavior, yet its buffering effect between job insecurity and safety performance has attracted little attention. In this study, organizational support in the safety field was identified as supervisory and coworker support for safety. Using conservation of resources theory, this paper tested the predictive powers of job insecurity, supervisory support for safety, and coworker support for safety on safety performance. Additionally, it tested the buffer effects of both supervisory and coworker support for safety on the relationship between job insecurity and safety performance. The data were collected via questionnaires from 470 high-speed railway drivers in China. The results showed that (1) job insecurity had negative impact on safety compliance and safety participation; (2) higher safety support from the supervisor and coworker were associated with higher safety compliance and safety participation; (3) both supervisory and coworker support for safety moderated the effect of job insecurity on safety compliance and safety participation, respectively. Finally, theoretical as well as practical implications were proposed and suggestions for future research were also provided based on the findings in this study.

Named data networking (NDN) enables fast and efficient content dissemination in mission-critical unmanned aerial vehicle ad hoc networks (UAANETs); however, its in-network caching mechanism brings a new security challenge: content poisoning. Poisoned content can contaminate the cache on the routers and isolate valid content from the network, leading to performance degradation or denial of service. To mitigate such attacks and enhance network-layer trust of NDN-based UAANETs, this article proposes a novel and systematic framework that integrates interest-key-content binding (IKCB), forwarding strategy, and on-demand verification to efficiently discover poisoned content. To further provide decentralized IKCB store and detect internal attackers, we introduce a lightweight permissioned blockchain system over NDN and develop a scalable adaptive delegate consensus algorithm. Our experimental results have demonstrated that our proposed framework can effectively purge poisoned content with low overhead, and our algorithms achieve great performance to fit UAANETs.

The combination of the trityl cation and a chiral weakly coordinating Fe(III)-based bisphosphate anion was used to develop a new type of a highly active carbocation Lewis acid catalyst. The stereocontrol potential of the chiral tritylium ion pair was demonstrated by its application in an enantioselective Diels–Alder reaction of anthracene.

The surface of nuclear waste container will be completely wetted by the groundwater infiltrating through the bentonite or concrete buffer after the closure of its deep geological disposal. Because of its excellent corrosion resistance, titanium is one of the candidates for the container materials for high-level nuclear waste (HLNW) disposal. However, once oxygen depleted in the large time scale deep geological disposal, titanium container will suffer from hydrogen embrittlement (HE). Therefore, in order to predict the potential danger of the HLNW container caused by HE, the hydrogen entry into titanium was studied at different temperatures in simulated deep geological environment of Beishan, which is the preselected HLNW disposal area in China. Devanathan-Stachurski cell methods were firstly implemented in measuring apparent hydrogen diffusivity in titanium with hydrides being formed during hydrogen charging at low temperature ranges (298–373 K). Given the characteristic of the Devanathan-Stachurski cell method's capable of getting apparent diffusivity with combined influencing factors easily, the technique provides a simple way to measure the parameter that is necessary for the estimation of hydrogen penetration depth, facilitating the design of HLNW containers.

This paper investigates the vision-based autonomous driving with deep learning and reinforcement learning methods. Different from the end-to-end learning method, our method breaks the vision-based lateral control system down into a perception module and a control module. The perception module which is based on a multi-task learning neural network first takes a driver-view image as its input and predicts the track features. The control module which is based on reinforcement learning then makes a control decision based on these features. In order to improve the data efficiency, we propose visual TORCS (VTORCS), a deep reinforcement learning environment which is based on the open racing car simulator (TORCS). By means of the provided functions, one can train an agent with the input of an image or various physical sensor measurement, or evaluate the perception algorithm on this simulator. The trained reinforcement learning controller outperforms the linear quadratic regulator (LQR) controller and model predictive control (MPC) controller on different tracks. The experiments demonstrate that the perception module shows promising performance and the controller is capable of controlling the vehicle drive well along the track center with visual input.

Tourmalines occur widely within leucogranites and pegmatites that intrude the leucogranites in the south Tibetan plateau. Morphological and geochemical (elemental and boron-isotopic) studies on these tourmalines are very limited. Furthermore, the tourmaline genetic correlation between the leucogranite and the pegmatite is also unknown. In this contribution, two types of tourmaline occurrences have been identified in the Conadong area, south Tibet, including randomly disseminated tourmaline in leucogranite (GT type) and radial, dendritic or massive tourmaline aggregates in pegmatite dikes that intrude the leucogranite (PT type). We performed major element and boron isotopic analyses of tourmaline using electron microprobe (EMPA) and laser ablation multi-collector inductively coupled plasma mass spectrometry, respectively. The two types of tourmalines are enriched in Fe, Na and Al but relatively depleted in Ca and Mg elements, with compositions close to alkali group tourmaline and schorl. All the tourmalines are likely the products of equilibrium crystallization and their dominance of Na was controlled by the magmatic compositions of their host rocks. The GT type tourmalines show a narrow range of δ11B values between −9.78 ± 0.81‰ and − 8.53 ± 0.68‰ (with a mean of −8.91 ± 0.18‰); whereas the PT type tourmalines have significantly lower δ11B values than the GT type, ranging from −14.02 ± 0.85‰ to −11.83 ± 0.57‰ (with a mean of −13.31 ± 0.49‰). These data together with their morphology and petrography indicate that the Conadong granitic tourmalines were derived by the melts at the early magmatic stage, whereas the pegmatitic tourmalines precipitated from magmatic–hydrothermal fluids at the late magmatic stage. The variation in boron isotopic compositions (Δ11B = 4.4‰) between the PT and the GT type tourmalines is most likely correlated with their different melt/fluid source regions that had distinct Sr-Nd-B isotopic compositions.

During the COVID-19 pandemic, the use of social media platforms for working online has become a global phenomenon. For female employees, social media usage has made it easier to balance work and family, but the pressures have also multiplied. Especially in China, the COVID-19 prevention policies led to dramatic changes in working patterns, which significantly affected the emotions, cognitions, and behaviors of female employees. Based on the job demands resource theory, this study explores the double-edged effect of social media usage on job crafting for female employees. Survey data were collected from 563 female employees in Chinese enterprises. Hierarchical regression analysis and the bootstrap method by SPSS and AMOS software were used to test the hypotheses. The results show that work-related social media usage has a negative effect on job crafting, while social-related social media usage has a positive effect. Moreover, job autonomy and workplace friendship mediate the relationship between them. This study extends the research on the double-edge effect of female employees’ social media usage and enriches the antecedents and influencing mechanisms of job crafting. It also provides theoretical and practical guidance for managers on how to promote the sustainability of human capital during the COVID-19 pandemic.

Earthworm bio-composting is an environmentally friendly way of processing agricultural organic waste, especially cow manure. In order to observe the temperature, humidity and conductivity of cow manure during the biological composting process of earthworms, a composting data collection system was designed to collect the above data. The experiment was carried out in an earthworm breeding farm in Changqing District, Jinan City, and lasted for 50 days, from October 21, 2020 to December 10, 2020. The experiment data can be used for data comparison with conventional composting, and can also provide a reference for the exploration of the earthworm composting process.

Environment perception is one of the most crucial modules in a self-driving system. In an open subway environment, pedestrians, equipment boxes and other unknown obstacles often appear. The perception module is required to quickly and accurately recognize the obstacle and measures the corresponding distance data. This paper proposes a detection and ranging fusion method based on one Lidar and two different focal length cameras, which be applied in the subway system, to alert drivers to possible obstacles and assist brake. First, the relative transformation between Lidar and camera is calibrated to find the intrinsic and extrinsic matrices. Modified SSD network is trained on the self-built dataset to detect the potential obstacle and produces the final detection bounding box. Then, rail track segmentation network RailNet is applied to obtain rail shape features, which offers a region of interest (ROI) for sensing systems in point cloud clustering algorithms. Further, the fusion information is utilized to estimate the distance of objects detected by the SSD detector. The proposed method can realize real-time pedestrian detection and range on the onboard embedded platform Jetson Xavier, which satisfies the subway environment's perception requirements.

Most ships currently use electric propulsion systems. In this system, the transformer plays a key role in power distribution. The probability of interturn short circuit occurs in the transformer is high, it will cause faults such as three-phase voltage imbalance and endanger the safe operation of the ship. The simulation model of ship electric propulsion system established in this paper includes propellers and transformers, and the influence of the interturn short circuit of a transformer on the sailing conditions is studied. The research results show that the transformer interturn short circuit will generate a huge inrush current and have a huge impact on the torque and speed of the propeller.

In view of the current status of research on verification of the correctness and effectiveness of FHFT design, a field-circuit coupling based FHFT design verification method is proposed in this paper. This paper proposes a FHFT design verification method based on field-circuit coupling. The steps of FHFT verification using field-circuit coupling method are elaborated in detail. A three-dimensional physical model of FHFT based on AP method is established. The calculation of FHFT flux density and the verifying of transformer output waveform are completed by using the field-circuit coupling method of alternating iteration of non-linear magnetic field solution and circuit. On the basis of completing the flux density calculation, the field circuit coupling method is used to verify the output waveform of the transformer. It is found that the output waveform of FHFT is not an ideal square wave, but has some distortion, which is caused by neglecting the leakage inductance of transformer in the design process. This shows that the influence of transformer leakage inductance is very important and should be paid attention to.

Detailed petrological and geochemical data.

Parasitoids have been extensively found to manipulate nutrient amounts of their hosts to benefit their own development and survival, but the underlying mechanisms are largely unknown. Leptopilina boulardi (Hymenoptera: Figitidae) is a larval-pupal endoparasitoid wasp of Drosophila melanogaster whose survival relies on the nutrients provided by its Drosophila host. Here, we used RNA-seq to compare the gene expression levels of the host midgut at 24 h and 48 h post L. boulardi parasitization. We obtained 95 and 191 differentially expressed genes (DEGs) in the parasitized host midgut at 24 h and 48 h post L. boulardi parasitization, respectively. A KEGG analysis revealed that several metabolic pathways were significantly enriched in the upregulated DEGs, and these pathways included “starch and sucrose metabolism” and “galactose metabolism”. A functional annotation analysis showed that four classes of genes involved in carbohydrate digestion process had increased expression levels in the midgut post L. boulardi parasitization than nonparasitized groups: glucosidase, mannosidase, chitinase and amylase. Genes involved in protein digestion process were also found among the DEGs, and most of these genes, which belonged to the metallopeptidase and serine-type endopeptidase families, were found at higher expression levels in the parasitized host midgut comparing with nonparasitized hosts. Moreover, some immune genes, particularly those involved in the Toll and Imd pathways, also exhibited high expression levels after L. boulardi parasitization. Our study provides large-scale transcriptome data and identifies sets of DEGs between parasitized and nonparasitized host midgut tissues at 24 h and 48 h post L. boulardi parasitization. These resources help improve our understanding of how parasitoid infection affects the nutrient components in the hosts.

In today&rsquo, s highly uncertain environment, the value of creativity and innovation are increasingly critical. How individuals could improve their creativity and innovation performance has become the focus of attention. Future work self as an intrinsic motivation factor plays an important role in creativity and innovation. Based on the self-consistency theory, this study integrated proactive personality and informal field-based learning (IFBL) to explore the relationship between future work self and employee creativity to increase innovation performance. It used data from 201 R&amp, D department employees in China&rsquo, s high-tech companies. The results show that future work self has a positive effect on employee creativity and that IFBL mediates the relationship between future work self and employee creativity. This process is then positively moderated by a proactive personality. This study&rsquo, s results help clarify the formation mechanism of creativity from the perspective of intrinsic motivation and indicate that future work self can drive individuals&rsquo, creativity and innovation efforts, especially under the consistency of self-concept, motivation and personality. This research also emphasizes the importance of IFBL in improving individual creativity and further organizational innovation performance. Implications for theory and management to help improve creativity and innovation performance are then discussed in detail.

Leptopilina syphax (Hymenoptera: Figitidae) is a newly recorded species of parasitic wasp, and it attacks the larval stage of Drosophilidae, mainly the Drosophila species. Few works have been done in the basic study of L. syphax, including the data of mitochondrial genome. In this study, the complete mitochondrial genome of L. syphax (GeneBank accession number: MT649407) was sequenced using Illumina HiSeq X Ten system. The mitochondrial genome is 15,882bp long and comprises 13 protein-coding genes, 2 ribosomal RNA genes and 22 transfer RNA genes. Meanwhile, 26 genes are in majority strand, and the remaining 11 genes are in minority strand. The overall base composition is 41.7% for A, 6.0% for G, 13.6% for C, and 38.7% for T, with an A + T content of 80.4%, respectively. We also performed a phylogenetic analysis with other known mitochondrial genomes of some parasitic wasps. The results show that L. syphax is closely related to L. boulardi, which is another Drosophila parasitoid.

Parasitoids are ubiquitous in natural ecosystems. Parasitic strategies are highly diverse among parasitoid species, yet their underlying genetic bases are poorly understood. Here, we focus on the divergent adaptation of a specialist and a generalist drosophilid parasitoids. We find that a novel protein (Lar) enables active immune suppression by lysing the host lymph glands, eventually leading to successful parasitism by the generalist. Meanwhile, another novel protein (Warm) contributes to a passive strategy by attaching the laid eggs to the gut and other organs of the host, leading to incomplete encapsulation and helping the specialist escape the host immune response. We find that these diverse parasitic strategies both originated from lateral gene transfer, followed with duplication and specialization, and that they might contribute to the shift in host ranges between parasitoids. Our results increase our understanding of how novel gene functions originate and how they contribute to host adaptation., Parasitism is a widespread evolutionary strategy. A study that spans functional and evolutionary genomics identifies the molecular basis and history underlying two genes that have mediated divergent parasitic strategies (specialist vs generalist) between two sister species of parasitoid wasp.

Intraspecific competition is a major force in mediating population dynamics, fuelling adaptation, and potentially leading to evolutionary diversification. Among the evolutionary arms races between parasites, one of the most fundamental and intriguing behavioural adaptations and counter-adaptations are superparasitism and superparasitism avoidance. However, the underlying mechanisms and ecological contexts of these phenomena remain underexplored. Here, we apply the Drosophila parasite Leptopilina boulardi as a study system and find that this solitary endoparasitic wasp provokes a host escape response for superparasitism avoidance. We combine multi-omics and in vivo functional studies to characterize a small set of RhoGAP domain-containing genes that mediate the parasite’s manipulation of host escape behaviour by inducing reactive oxygen species in the host central nervous system. We further uncover an evolutionary scenario in which neofunctionalization and specialization gave rise to the novel role of RhoGAP domain in avoiding superparasitism, with an ancestral origin prior to the divergence between Leptopilina specialist and generalist species. Our study suggests that superparasitism avoidance is adaptive for a parasite and adds to our understanding of how the molecular manipulation of host behaviour has evolved in this system., Evolutionary arms races can drive adaptations in hosts and parasites as well as among competing parasites. A combination of multi-omics and functional tests identifies a set of genes that allow a parasitic wasp to minimize intraspecific competition by inducing hosts to escape before more wasps can parasitize them.

To clearly understand TCC (transient circulating current), which is one of the most important EMI (electromagnetic interference) source of GIS (gas insulated substation), a research about TCC is carried out. The generation mechanism of TCC is analyzed, and a current transformer coupling method to calculate TCC accurately is presented. Then, this paper focus on setting up the model of SF6 gas discharge, which is the key problem of calculating TCC. According to the impedance variation characteristic of SF6 gas discharge, an exponential reignition model is set up and the typical transient parameters such as amplitude, rise steepness, duration, decay time and frequency are calculated. The results show that: 1) The positive and negative maximum value of TCC with UHV(ultra-high voltage) voltage level is about 129.90 $A$ and −108.37 $A$ respectively, and the positive value of TCC is always larger than that of the negative; 2) the rise steepness of TCC waveform can reach $321.39\ A/\mu s$ , the duration and decay time is about 12 ms and $24.32\ \mu s$ , respectively; 3) the frequency of TCC distributes at the range of 0∼417 MHz, and the dominant frequency is 5∼20 MHz and 30∼35 MHz.

As the basis of scenes understanding for the track inspection task, track segmentation is challenging due to the various illumination conditions, track crossing, and plant coverage. Since the rail has a strong shape prior, strict rail spacing and special distribution in the image, making full use of the spatial information of the rail features becomes an important factor to improve the accuracy of rail segmentation. In this paper, an information aggregation module is proposed to enhance the spatial relationship between pixels of the rail features. In other words, this module expands the receptive field. Furthermore, we build an information aggregation network based on this module, which is called as RailNet. Finally, the RailNet is evaluated in an open train track dataset. Experimental results show that RailNet can achieve the best performance so far in the dataset of trains.

Porous titanium scaffold has been prepared by freeze casting of TiH2 aqueous slurry for the application of structural core of sandwiches, filters, heat exchangers and bones due to the directional lamellar structure. The effects of freezing temperature and solid content, which are decisive parameter in freezing casting process, on porous structure are revealed. As freezing temperature drops and solid content increases, the porosity ranges from 15% to 73%, wall thickness increases from 8 µm to more than 15 µm. Different structures provide different mechanical properties. With the decrease of porosity, the yield strength in the direction parallel to the freezing direction rose from 60 MPa to 286 MPa while Young’s modulus is from 0.8 GPa to 11.2 GPa. The fracture mode changes from surface fragmentation to body fragmentation along with partial splitting. The modified Gibson - Ashby formula was used to describe the relationship between the mechanical properties and the relative density. The constant and exponents of mechanical properties with porosity are much higher than the conventional process, which indicated excellent mechanical properties compared with other processes.