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Abstract The hypothalamus plays an important role in aging, but it remains unclear regarding the underlying epigenetics and whether this hypothalamic basis can help address aging-related diseases. Here, by comparing mouse hypothalamus with two other limbic system components, we show that the hypothalamus is characterized by distinctively high-level DNA methylation during young age and by the distinct dynamics of DNA methylation and demethylation when approaching middle age. On the other hand, age-related DNA methylation in these limbic system components commonly and sensitively applies to genes in hypothalamic regulatory pathways, notably oxytocin (OXT) and gonadotropin-releasing hormone (GnRH) pathways. Middle age is associated with transcriptional declines of genes which encode OXT, GnRH and signaling components, which similarly occur in an Alzheimer’s disease (AD)-like model. Therapeutically, OXT-GnRH combination is substantially more effective than individual peptides in treating AD-like disorders in male 5×FAD model. In conclusion, the hypothalamus is important for modeling age-related DNA methylation and developing hypothalamic strategies to combat AD.

Abstract Institutions are increasingly employing algorithms to provide performance feedback to individuals by tracking productivity, conducting performance appraisals, and developing improvement plans, compared to traditional human managers. However, this shift has provoked considerable debate over the effectiveness and fairness of algorithmic feedback. This study investigates the effects of negative performance feedback (NPF) on the attitudes, cognition and behavior of medical researchers, comparing NPF from algorithms versus humans. Two scenario-based experimental studies were conducted with a total sample of 660 medical researchers (algorithm group: N1 = 411; human group: N2 = 249). Study 1 analyzes the differences in scientific misconduct, moral disengagement, and algorithmic attitudes between the two sources of NPF. The findings reveal that NPF from algorithms shows higher levels of moral disengagement, scientific misconduct, and negative attitudes towards algorithms compared to NPF from humans. Study 2, grounded in trait activation theory, investigates how NPF from algorithms triggers individual’s egoism and algorithm aversion, potentially leading to moral disengagement and scientific misconduct. Results indicate that algorithm aversion triggers individuals’ egoism, and their interaction enhances moral disengagement, which in turn leads to increased scientific misconduct among researchers. This relationship is also moderated by algorithmic transparency. The study concludes that while algorithms can streamline performance evaluations, they pose significant risks to scientific misconduct of researchers if not properly designed. These findings extend our understanding of NPF by highlighting the emotional and cognitive challenges algorithms face in decision-making processes, while also underscoring the importance of balancing technological efficiency with moral considerations to promote a healthy research environment. Moreover, managerial implications include integrating human oversight in algorithmic NPF processes and enhancing transparency and fairness to mitigate negative impacts on medical researchers’ attitudes and behaviors.

Due to the development and utilization of nuclear energy, the safe disposal of nuclear waste needs to be urgently addressed. In recent years, the utilization of microorganisms’ adsorption capacity to dispose of radioactive waste has received increasing attention. When compared with conventional disposal methods, microbial adsorption exhibits the characteristics of high efficiency, low cost, and no secondary pollution. In the long term, microbial biomass shows significant promise as specific chemical-binding agents. Optimization of biosorption conditions, identification of rare earth element binding sites, and studies on the sorption capacities of immobilized cells provide compelling reasons to consider biosorption for industrial applications in heavy metal removal from solutions. However, the interaction mechanism between microorganisms and radioactive nuclides is very complex. This mini-review briefly provides an overview of the preparation methods, factors affecting the adsorption capacity, and the mechanisms of microbial adsorbents.

Multipath effects can significantly reduce the accuracy of GNSS precise positioning. Traditional methods, such as sidereal filtering and grid-based approaches, attempt to model and mitigate these errors by leveraging the spatial autocorrelation of multipath based on residuals. However, these methods can only approximately handle spatial autocorrelation data, limiting their effectiveness. This study investigates the spatial cross-correlation of residuals between various GNSS frequency bands, analyzes their covariance function parameters, and evaluates the impact of constellation shifts on long-term multipath mitigation. Based on this, a simplified autocorrelation-based approach utilizing unified covariance parameters for multipath mitigation is proposed, with its efficacy assessed for both short- and long-term applications. The study demonstrates the correlation of multipath effects across various GPS and Galileo frequencies, including GPS L1/L2/L5 and Galileo E1/E5a/E5b/E5ab/E6, by analyzing correlation coefficients. A strong correlation (greater than 0.8) is observed between residuals of closely spaced frequencies, such as E5b and E5ab, despite their frequency differences. Additionally, the covariance parameters of the residuals are found to be consistent across all frequencies for a baseline, suggesting that unified parameters can be applied effectively for spatial autocorrelation-based multipath mitigation without sacrificing performance. The orbit shifts of certain GPS satellites, particularly G02, G20, and G21, result in significant changes in orbital parameters and satellite tracks, reducing the effectiveness of long-term multipath mitigation. However, the impact of GPS orbit shifts can be minimized through periodic model updates or by integrating GPS and Galileo modeling. In experiments, the LSC correction strategy based on a GPS/Galileo combination, utilizing unified parameters, outperforms the grid method based on the GPS/Galileo combination, improving the mean residual variance elimination rate by 11.3% for GPS L1 and 11.4% for Galileo E1. These improvements remain consistent, with rates of 11.3% and 15.7%, respectively, even on DOY 365, which is 327 days after the modeling data were collected.

The success of an organism depends on the molecular and ecological adaptations that promote its beneficial fitness. Parasitoids are valuable biocontrol agents for successfully managing agricultural pests, and they have evolved diversified strategies to adapt to both the physiological condition of hosts and the competition of other parasitoids. Here, we deconstructed the parasitic strategies in a highly successful parasitoid, Trichopria drosophilae, which parasitizes a broad range of Drosophila hosts, including the globally invasive species D. suzukii. We found that T. drosophilae had developed specialized venom proteins that arrest host development to obtain more nutrients via secreting tissue inhibitors of metalloproteinases (TIMPs), as well as a unique type of cell—teratocytes—that digest host tissues for feeding by releasing trypsin proteins. In addition to the molecular adaptations that optimize nutritional uptake, this pupal parasitoid has evolved ecologically adaptive strategies including the conditional tolerance of intraspecific competition to enhance parasitic success in older hosts and the obligate avoidance of interspecific competition with larval parasitoids. Our study not only demystifies how parasitoids weaponize themselves to colonize formidable hosts but also provided empirical evidence of the intricate coordination between the molecular and ecological adaptations that drive evolutionary success.

The signaling environment, or niche, often governs the initial difference in behavior of an adult stem cell and a derivative that initiates a path towards differentiation. The transition between an instructive stem cell niche and differentiation niche must generally have single-cell resolution, suggesting that multiple mechanisms might be necessary to sharpen the transition. Here, we examined the Drosophila ovary and found that Cap cells, which are key constituents of the germline stem cell (GSC) niche, express a conserved microRNA (miR-124). Surprisingly, loss of miR-124 activity in Cap cells leads to a defect in differentiation of GSC derivatives. We present evidence that the direct functional target of miR-124 in Cap cells is the epidermal growth factor receptor (EGFR) and that failure to limit EGFR expression leads to the ectopic expression of a key anti-differentiation BMP signal in neighboring somatic escort cells (ECs), which constitute a differentiation niche. We further found that Notch signaling connects EFGR activity in Cap cells to BMP expression in ECs. We deduce that the stem cell niche communicates with the differentiation niche through a mechanism that begins with the selective expression of a specific microRNA and culminates in the suppression of the major anti-differentiation signal in neighboring cells, with the functionally important overall role of sharpening the spatial distinction between self-renewal and differentiation environments.

The quality of a crowdsourcing virtual community is an essential factor that stimulates users' perceptions of belonging and attachment to the community, thereby influencing their behavior. As a prerequisite for the development of “creative crowdsourcing,” it is particularly important to study how users' voice behavior can be promoted in virtual communities. Drawing on the Stimulus-Organism-Response (SOR) framework and the Social Identification Theory, this study developed a conceptual model that investigates the impact of crowdsourcing virtual communities in system, information, interaction, and service quality on users' voice behavior. Furthermore, we introduce community identification and self-disclosure to further analyze the influencing mechanism between these two variables. Data were collected through 672 survey questionnaires from participants in well-known crowdsourcing virtual communities such as Xiaohongshu, Bilibili, Haier Hope, Test Baidu, and Test China. Using hierarchical regression and bootstrap analysis, we found a positive correlation between the quality of the crowdsourcing virtual community and users’ voice behavior, with community identification acting as a mediator. Furthermore, self-disclosure showed a significant moderating effect on the relationship between community identification and voice behavior. These findings significantly contribute to the theoretical landscape by advancing the SOR framework within a virtual community. This not only deepens the understanding of the quality of the crowdsourcing virtual community, but also provides theoretical and practical implications for managers and users on how to promote voice behavior.

Metal oxides can be doped by various metal ions to tune the properties. While the migration of metal ions especially extrinsic metal ions in metal oxides still needs to be clarified in order to adjust the composition and the structure of metal oxides properly. Here, 14 kinds of metal oxide powders were utilized to investigate the key factors of Zn ion migration in metal oxide powders experimentally. Results show that chemical reactions and/or phase transitions in metal oxides can hinder the migration of Zn ions in metal oxide powders. Compared with unstable metal oxides, it is easier for Zn ions to pass through stable metal oxides which maintain the same component phases at elevated temperatures. Transition from unstable metal oxide medium to stable metal oxide medium will make the transport of Zn ions in the medium from impossible to possible. These findings are helpful for selecting proper metal oxides in related industries such as battery designing, gas sensor development and so on.

A large amount of nuclear waste produced in the process of nuclear energy utilization has always been a key problem to be solved urgently for nuclear safety. At present, “deep geological disposal” is a feasible method and generally accepted by many countries. The oxygen content in the near field environment of the waste container will decrease to anaerobic conditions, and hydrogen will permeation into the internal materials of container for a long time. Hydrogen evolution corrosion may cause a risk of hydrogen embrittlement. The harm of hydrogen embrittlement in metal container is far more severe than predictable uniform corrosion. It is a research hotspot that the microorganisms impact on the corrosion behavior of container materials in the deep geological environment. Microbial corrosion in deep geological environments can be divided into two types: aerobic microbial corrosion and anaerobic microbial corrosion. There is a type of hydrogen consuming microorganism in the natural environment that uses the oxidation of hydrogen as the energy for its life activities. This provides a new approach for us to study reducing the hydrogen embrittlement sensitivity of nuclear waste container materials.

Animals have evolved varied strategies for predator avoidance. Here the authors find that Drosophila can recognize threats from younger parasitoid wasps via the perception of their search performance, and reduce egg laying through the reduction of octopamine neuronal signalling.

The removal of decabromodiphenyl ether (BDE 209), as a typical persistent organic pollutant (POP), is of worldwide concern. Mechanochemical (MC) processes are promising methods to degrade environmental pollutants, most of which use a single grinding reagent. The performance of MC processes with co-milling agents still needs to be further verified. In this study, an efficient MC treatment with combined utilization of lithium cobalt oxide (LiCoO2) and iron (Fe) as co-milling reagents for BDE 209 degradation was investigated. The synchronous action of LiCoO2 and Fe with a LiCoO2/Fe/Br molar ratio of 1.5:1.67:1 and a ball-to-powder ratio of 100:1 led to almost thorough-paced abatement and debromination of BDE 209 within 180 min using a ball milling rotation speed of 600 rpm. The reduction in particle sizes and the destruction of crystal structure in mixture powders with the increase in milling time induced the enhanced degradation of BDE 209, as characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The X-ray photoelectron spectroscopy (XPS) characterization showed that the valence state of Co was converted from Co(III) to Co(II), and Fe(0) was changed to Fe(III) when treated with an MC process. This indicated that the reductive debromination of BDE 209 by Fe and the following oxidative degradation of debrominated products by LiCoO2 were integrated in a concerted way. It proved the removal of BDE 209 via an MC treatment. The full breakage of C-Br and C-O bonds in BDE 209 was confirmed by Fourier transform-infrared spectrometry (FT-IR) spectra, and a possible abatement pathway was also proposed based on the identified intermediate products using gas chromatography–mass spectrometry (GC-MS). These obtained results indicated that a combination of LiCoO2 and Fe as co-milling reagents is promising in the MC treatment of toxic halogenated pollutants like BDE 209.

Carrier Smoothing Code (CSC), as a low-pass filter, has been widely used in GNSS positioning processing to reduce pseudorange noise via carrier phases. However, current CSC methods do not consider the systematic bias between the code and carrier phase observation, also known as Satellite-induced Code Bias (SICB). SICB has been identified in the BDS-2 and the bias will reduce the accuracy or reliability of the CSC. To confront bias, an improved CSC algorithm is proposed by considering SICB for GEO, IGSO, and MEO satellites in BDS constellations. The correction model of SICB for IGSO/MEO satellites is established by using a 0.1-degree interval piecewise weighted least squares Third-order Curve Fitting Method (TOCFM). The Variational Mode Decomposition combined with Wavelet Transform (VMD-WT) is proposed to establish the correction model of SICB for the GEO satellite. To verify the proposed method, the SICB model was established by collecting 30 Multi-GNSS Experiment (MGEX) BDS stations in different seasons of a year, in which the BDS data of ALIC, KRGG, KOUR, GCGO, GAMG, and SGOC stations were selected for 11 consecutive days to verify the effectiveness of the algorithm. The results show that there is obvious SICB in the BDS-2 Multipath (MP) combination, but the SICB in the BDS-3 MP is smaller and can be ignored. Compared with the modeling in the references, TOCFM is more suitable for IGSO/MEO SICB modeling, especially for the SICB correction at low elevation angles. After the VMD-WT correction, the Root Mean Square Error (RMSE) of SICB of B1I, B2I, and B3I in GEO satellites is reduced by 53.35%, 63.50%, and 64.71% respectively. Moreover, we carried out ionosphere-free Single Point Positioning (IF SPP), Ionosphere-free CSC SPP (IF CSC SPP), CSC single point positioning with the IGSO/MEO SICB Correction based on the TOCFA Method (IGSO/MEO SICB CSC), and CSC single point positioning with the IGSO/MEO/GEO SICB correction based on VMD-WT and TOCFA (IGSO/MEO/GEO SICB CSC), respectively. Compared to IF SPP, the average improvement of the IGSO/MEO/GEO SICB CSC algorithm in the north, east, and up directions was 24.42%, 27.94%, and 24.98%, respectively, and the average reduction in 3D RMSE is 24.54%. Compared with IF CSC SPP, the average improvement of IGSO/MEO/GEO SICB CSC is 7.03%, 6.50%, and 10.48% in the north, east, and up directions, respectively, while the average reduction in 3D RMSE was 9.86%. IGSO/MEO SICB mainly improves the U direction positioning accuracy, and GEO SICB mainly improves the E and U direction positioning accuracy. After the IGSO/MEO/GEO SICB correction, the overall improvement was about 10% and positioning improved to a certain extent.

A large amount of nuclear waste produced in the process of nuclear energy utilization has always been a key problem to be solved urgently for nuclear safety. At present, “deep geological disposal” is a feasible method and is generally accepted by many countries. It is a “multi-barrier system” composed of an artificial barrier, including the solidified waste body, outer packaging material, buffer backfill material, and a natural barrier including the surrounding rock. During deep geological disposal, a near-field environment, where the corrosion of a container could happen, is formed with continuous groundwater infiltration and the release of much heat energy in the process of nuclear waste decay and fission. At the same time, the environment will become a long-term reduction place because of the gradual consumption of the initially retained oxygen. The hydrogen evolution reaction is dominant, so unpredictable hydrogen embrittlement of the container materials could happen due to hydrogen absorption and penetration. This study summarizes the possibility of hydrogen embrittlement of carbon steel, titanium, and their alloys from three aspects, namely, hydrogen solubility, diffusion coefficient, and hydrogen embrittlement, which provides a theoretical basis for predicting the container life in a large time scale.

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.

After a nuclear waste container buried 500–1,000 m underground, it gradually experiences the dual effects of groundwater infiltration and the decay heat of radioactive nuclear waste. The decay and heat release of nuclear waste will also result in temperature stress. At the same time, the groundwater will gradually saturate the buffer/backfill materials which will produce expansion stress, thus forming a typical thermal–water–stress multi-coupling environment in the geological disposal, forming the environment where the corrosion could happen. In comparison, the information obtained through laboratories, field tests, and natural simulations are limited. However, numerical simulation is very important to predict the changes of a near-field environment. On one hand, the numerical simulation can verify the corresponding experimental data in the early stages; on the other hand, it can also predict the long-term corrosion environment change. This article mainly summarizes the large-scale evolution of a typical corrosion environment obtained by numerical simulation under different deep geological conditions in various countries, focusing on the effects of temperature, saturation, oxygen content, and radiation, which provide a reference for the research on the evolution of important corrosion environments on the surface of a nuclear waste container.

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.

The domain name system (DNS) is an important internet infrastructure.However,current DNS utilizes centralized hierarchical structure with severe dependence on root server,which causes defects such as the risk of single-point failure and the abuse of central rights.Designing new decentralized DNS mainly focuses on transforming the domain name system from a single trust domain which relies on the center to multiple trust domains with the top-level domain name as the root parallel to each other,but also faces cross-domain credible challenges.To design a cross-domain trusted architecture,the concept of separating control and analysis was adopted,and a dual-blockchain DNS architecture was proposed.At data layer,a novel cross-domain verification was designed based on a one-way accumulator verification scheme,with the time complexity of the verification process O(N) reducing to O(1) nearly.The CDBFT algorithm was proposed by combining the DPoS mechanism and the BFT algorithm,whose average throughput reaches 736 TPS.The theoretical derivation and experimental results have demonstrated the advantages of this new DNS architecture on security,performance,and scalability.

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.

Deep geological disposal is the most reliable method for high-level nuclear waste, of which metal container as the first barrier for deep geological disposal of high-level nuclear waste is particularly important. Carbon steel is used as a container material because of the low possibility of local corrosion in bentonite. However, after the storage is closed, the decrease of oxygen content will create a near-field environment where the hydrogen embrittlement (HE) in the corrosion process of the container could happen. To evaluate the safety of containers in deep geological disposal of Beshai, the preselected area in China, hydrogen permeation efficiency and HE were estimated in highly pressed saturated bentonite by electrochemical and extrapolation analyses. It is concluded that hydrogen permeation efficiency increases with the disposal year, which proves that the hydrogen evolution reaction dominates the cathode process in the corrosion during long-term disposal. However, slow strain rate tensile shows that Q235 steel has a low HE sensitivity.

The domesticated silkworm, Bombyx mori, is an economically important insect that synthesizes large amounts of silk proteins in its silk gland to make cocoons. In recent years, germline transformation strategies advanced the bioengineering of the silk gland as an ideal bioreactor for mass production of recombinant proteins. However, the yield of exogenous proteins varied largely due to the random insertion and gene drift caused by canonical transposon-based transformation, calling for site-specific and stable expression systems. In the current study, we established a targeted in-fusion expression system by using the transcription activator-like effector nuclease (TALEN)-mediated targeted insertion to target genomic locus of sericin, one of the major silk proteins. We successfully generated chimeric Sericin1-EGFP (Ser-2A-EGFP) transformant, producing up to 3.1% (w/w) of EGFP protein in the cocoon shell. With this strategy, we further expressed the medically important human epidermal growth factor (hEGF) and the protein yield in both middle silk glands, and cocoon shells reached to more than 15-fold higher than the canonical piggyBac-based transgenesis. This natural Sericin1 expression system provides a new strategy for producing recombinant proteins by using the silkworm silk gland as the bioreactor.

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.

Etch pits could form on an exposed surface of a crystal when the crystal is exposed to an etching environment or chemicals. Due to different dissolution rates along various crystalline directions in a crystal, the dissolution process is anisotropic; hence, etch pits usually have a regular shape. Here, the morphology and origin of the regular-shaped etch pits are discussed firstly; then, factors which could affect the morphology and density of etch pits are shown; finally, the state of the art of etch pit technology and the utilization of etch pits is presented. Traditionally, etch pits are utilized to evaluate the dislocation density and some defect-related properties. Now, in the modern fabrication industries, the relationship between etch pits and defects has been utilized more skillfully. High-quality crystals can be fabricated by controlling dislocations revealed by etch pits. Meanwhile, with the as-revealed dislocation as the diffusion path of atoms, new crystals will emerge in corresponding etch pits.

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.

With the development of the shipping industry, Automatic Identification System (AIS) used for ship communication becomes more and more important. Aiming at the problem of mixing position estimation of AIS mixed signals, this paper improves the double sliding-window detection algorithm to estimate the mixing position of miscellaneous signals accurately. There is a significant difference in energy between the aliased and unmixed parts of the mixed signal. When unmixed parts just enter one of the energy detections windows, the decision function reaches its peak value by establishing a proper decision function, that is to say, the position of the beginning and end of the mixing part is estimated. The simulation results show that the proposed algorithm which is compared with the frequency and amplitude detection algorithm can achieve the mixing position estimation with low complexity and strong robustness, and the estimation accuracy is close to the Cramer-Rao Bound under the condition of the high signal-to-noise ratio.

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.

Abstract Titanium dioxide (TiO2) nanotube arrays coupled with a narrow gap semiconductor—bismuth selenide (Bi2Se3)—exhibited remarkable enhancement in the photocathodic protection property for 304 stainless steel under visible light. Bi2Se3/TiO2 nanocomposites were successfully synthesized using a simple two-step method, including an electrochemical anodization method for preparing pure TiO2 and a chemical bath deposition method for synthesizing Bi2Se3 nanoflowers. The morphology and structure of the composite films were studied by scanning electron microscopy, energy dispersion spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. In addition, the influence of the Bi2Se3 content on the photoelectrochemical and photocathodic protection properties of the composite films was also studied. The photocurrent density of the Bi2Se3/TiO2 nanocomposites was significantly higher than that of pure TiO2 under visible light. The sensitizer Bi2Se3 enhanced the efficient separation of the photogenerated electron-hole pairs and the photocathodic protection properties of TiO2. Under visible light illumination, Bi2Se3/TiO2 nanocomposites synthesized by the chemical bath deposition method with Bi3+ (0.5 mmol/L) exhibited the optimal photogenerated cathodic protection performance for 304 stainless steel.

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.

In this paper, a finite element model for the particle-impact target is established for the abrasion erosion failure behavior of 20# steel used in natural gas gathering pipelines. The JC plastic model and failure criterion are used in the model to simulate the failure and damage of the material, and the reliability of the model was verified by comparison with experimental data. The dynamic behavior of particle erosion was studied by using this model. The changes of energy, stress, and morphology at the microscopic level were analyzed. The influence of particle shape, particle size, impact velocity, and impact angle on the erosion rate of 20# steel was obtained. The model is further used to study the influence mechanism of stress interference on erosion damage behavior under multiparticle random drop impact.