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Abstract We provide a remote sensing derived dataset for large-scale ground-mounted photovoltaic (PV) power stations in China of 2020, which has high spatial resolution of 10 meters. The dataset is based on the Google Earth Engine (GEE) cloud computing platform via random forest classifier and active learning strategy. Specifically, ground samples are carefully collected across China via both field survey and visual interpretation. Afterwards, spectral and texture features are calculated from publicly available Sentinel-2 imagery. Meanwhile, topographic features consisting of slope and aspect that are sensitive to PV locations are also included, aiming to construct a multi-dimensional and discriminative feature space. Finally, the trained random forest model is adopted to predict PV power stations of China parallelly on GEE. Technical validation has been carefully performed across China which achieved a satisfactory accuracy over 89%. Above all, as the first publicly released 10-m national-scale distribution dataset of China’s ground-mounted PV power stations, it can provide data references for relevant researchers in fields such as energy, land, remote sensing and environmental sciences.

Abstract Background The red-crowned crane is one of the vulnerable bird species. Although the captive population has markedly increased over the last decade, infectious diseases can lead to the death of young red-crowned cranes while few virological studies have been conducted. Methods Using a viral metagenomics approach, we analyzed the virome of tissues of the dead captive red-crowned crane with diarrhea symptoms in Dongying Biosphere Reserve, Shandong Province, China and feces of individual birds breeding at the corresponding captive breeding center, which were pooled separately. Results There is much more DNA and RNA viruses in the feces than that of the tissues. RNA virus belonging to the families Picornaviridae, and DNA viruses belonging to the families Parvoviridae, associated with enteric diseases were detected in the tissues and feces. Genomes of the picornavirus, genomovirus, and parvovirus identified in the study were fully characterized, which further suggested that infectious viruses of these families were possibly presented in the diseased red-crowned crane. Conclusion RNA virus belonging to the families Picornaviridae, and DNA viruses belonging to the families Genomoviridae and Parvoviridae were possibly the causative agent for diarrhea of red-crowned crane. This study has expanded our understanding of the virome of red-crowned crane and provides a baseline for elucidating the etiology for diarrhea of the birds.

ABSTRACT: Avian leukosis virus subgroup K (ALV-K) is composed of newly emerging isolates, which cluster separately from the well-characterized subgroups A, B, C, D, E, and J in sequence analysis, and exhibits a specific host range and a unique pattern of superinfection interference. Avian leukosis virus subgroup K replicate more slowly in avian cells than other ALV strains, leading to escaped detection during ALV eradication, but the underlying mechanism are largely unknown. In our previous study, we have reported that JS11C1 and most of other suspected ALV-K strains possessed unique mutations in the U3 region. Here, we selected 5 mutations in some important transcriptional regulation elements to explore the possible factor contributing for the lower activity of LTR, including CA-TG mutation in the CAAT box, 21 nt deletion in the CAAT box, A-G and A-T mutations in the CArG boxes, 11 nt insertion in the PRE boxes, and C-T mutation in the TATA box. On the basis of infectious clone of JS11C1, we demonstrated that the 11 nt fragment in the PRE boxes was associated with the transcription activity of LTR, the enhancer ability of U3, and the replication capacity of the virus. Notably, we determined the differential U3-protein interaction profile of ALVs and found that the 11 nt fragment specifically binds to cellular SERPINE1 mRNA binding protein 1 (SERBP1) to increase the LTR activity and enhance virus replication. Collectively, these findings reveal that a 11 nt fragment in the U3 gene contributed to its binding ability to the cellular SERBP1 to enhance its transcription and the infectious virus productions in avian cells. This study highlighted the vital role of host factor in retrovirus replication and thus provides a new perspective to elucidate the interaction between retrovirus and its host and a molecular basis to develop efficient strategies against retroviruses.

ABSTRACTDue to their important role in maintaining temperature and soil moisture, agricultural plastic covers have been widely utilized around the globe for improving crop-growing conditions, which include both plastic-covered greenhouses (PCGs) and plastic-mulched farmlands (PMFs). However, it is a challenging and long-neglected issue to separate PCGs from PMFs due to their spectral similarity. The objective of this study is to propose a deep semantic segmentation model for accurate PCG and PMF mapping based on very high-resolution satellite images and to improve the model’s spatial generalization capability using a transfer learning strategy. Specifically, the proposed semantic segmentation model has an encoder-decoder structure, where the encoder is composed of a new convolutional neural network for discriminative spatial feature learning, while the decoder utilizes a multi-task strategy to improve the predictions on the boundaries. Meanwhile, a transfer learning framework is adopted to increase mapping performance and generalization ability under limited samples. Experimental results in several typical regions across the Eurasian continent show that the proposed model could separate PCGs from PMFs accurately with a mean overall accuracy of 94.49% and an average mIoU of 0.8377. Ablation studies verify the role of encoder-decoder and transfer learning strategy in improving classification performance.

2,4-dinitrophenol (2,4-DNP) is a new kind of pollutant that is highly toxic and difficult to be biodegraded. In this study, the feasibility of using exogenous growth regulator salicylic acid (SA) to improve the purification ability of Salix matsudana (S. matsudana) seedlings to 2,4-DNP stress was investigated by a hydroponic simulation experiment. The main research results are as follows: (1) After adding exogenous SA, a high concentration of SA (1000 mg·L−1) inhibited the photosynthetic process and the normal physiological process of the chlorophyll fluorescence system of S. matsudana seedlings to a certain extent. When adding a low concentration of SA (10 mg·L−1) to treat S. matsudana seedlings, all exogenous treatment groups could alleviate the stress of 2,4-DNP on the photosynthetic system and chlorophyll fluorescence system of S. matsudana seedlings, and 10 mg·L−1 SA (DNP + S1) was the best. (2) The addition of exogenous SA could alleviate the damage of 2,4-DNP to S. matsudana seedlings by enhancing the activity of its antioxidant enzymes to remove excess reactive oxygen species (ROS) in the body and reducing the level of membrane lipid peroxidation and the size of membrane damage. The treatment with 10 mg·L−1 SA had the best effect. (3) Exogenous low concentration of SA (10 mg·L−1) could alleviate the decline of biomass index of S. matsudana seedlings under 2,4-DNP stress, but a high concentration of SA (1000 mg·L−1) could not alleviate the 2,4-DNP toxicity of S. matsudana seedlings leaves. Exogenous SA could effectively alleviate the growth damage caused by 2,4-DNP stress on S. matsudana seedlings and increase the tolerance threshold range of S. matsudana seedlings to 2,4-DNP (8.81–33.78 mg·L−1). (4) Exogenous addition of SA could increase the removal percentage of 2,4-DNP in Salix matsudana seedlings. Among them, the removal percentage of Salix matsudana was the highest at 10 mg·L−1 SA, which was 1.46 times (5 days) and 1.19 times (10 days) higher than that of the DNP treatment group, respectively. Overall, when SA reached 10 mg·L−1, the photosynthetic productivity of S. matsudana was the highest, and S. matsudana had the best purification effect on 2,4-DNP in wastewater.

Callose contributes to many biological processes of higher plants including pollen development, cell plate and vascular tissue formation, as well as regulating the transport function of plasmodesmata. The functions of callose synthase genes in maize have been little studied. We describe a maize male-sterile mutant 39 (ms39) characterized by reduced plant height. In this study, we confirmed using CRISPR/Cas9 technology that a mutation in Zm00001d043909 (ZmCals12), encoding a callose synthase, is responsible for the male sterility of the ms39 mutant. Compared with male-fertile plants, callose deposition around the dyads and tetrads in ms39 anthers was significantly reduced. Increased cell autophagy observed in ms39 anthers may have been due to the premature programmed cell death of tapetal cells, leading to collapse of the anther wall structure. Disordered glucose metabolism in ms39 may have intensified autophagy in anthers. Evaluation of the ms39 gene on maize heterosis by paired-crossed experiment with 11 maize inbred lines indicated that ms39 can be used for maize hybrid seed production.

Introduction: Treatment of relapsed or refractory acute myeloid leukemia (R/R AML) and myeloid sarcoma (MS) has presented challenges for decades. Studies on selinexor in combination with various standard or intensive chemotherapy regimens for the treatment of R/R AML have demonstrated promising results. This study aimed to evaluate the efficacy and safety of chemotherapy-free or low-dose chemotherapy regimens with selinexor for R/R AML and MS patients.Methods: Ten patients with R/R AML or MS who received chemotherapy-free or low-dose chemotherapy regimens in combination with selinexor at Tongji Hospital from October 2021 to August 2022 were included in this study. The primary endpoint was overall response rate (ORR) and secondary endpoints included complete remission (CR), CR with incomplete hematological recovery (CRi), partial remission (PR), transplantation rate, and safety.Results: All patients were evaluable for response, achieving CR in four (40.0%) patients and CRi in two (20.0%) patients for a total CR/CRi of 60.0%. The ORR was 80.0% when patients with PR were included. Five (50.0%) patients underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) after treatment with selinexor-containing regimens. At the end of the follow-up, seven (70.0%) patients were alive, and three patients died of transplant-related complications or disease progression. The most frequently reported nonhematologic adverse events (AEs) in patients were grade 1 or 2 asymptomatic hyponatremia.Conclusion: The chemotherapy-free or low-dose chemotherapy regimens in combination with selinexor for R/R AML are feasible and tolerable and provide an opportunity for patients to receive transplantation.

Abstract This paper introduces the worldwide history of fully automatic operation (FAO) system in urban rail transit, followed by the development status in China. Then, the architecture and characteristics of the FAO system are described, and the analysis method of system design requirements is proposed based on the human factors engineering. The key technologies are introduced from the aspects of signaling system, vehicle system, communication system, traffic integrated automation system and reliability, availability, maintainability, and safety (RAMS) assurance. Furthermore, based on the independent practical experience of the FAO system, this paper summarizes the management methods for the construction and operation of FAO lines and prospects its future development trends toward a more intelligent urban rail transit system.

At present, most studies have shown that probiotics have a positive regulatory effect on the nutritional metabolism of the body, but the mechanism is still unclear. Here, 48 piglets were divided into four groups. The control group was not fed probiotics, the Lac group was fed L. Rhamnosus GG ATCC53103, the Rha group was fed L. Plantarum JL01, and the mix group was fed two types of probiotics. Nitrogen metabolism and mRNA levels of mTOR and S6K in skeletal muscle were observed in each group. Then, metagenome and non-targeted metabonomics were used to observe the changes of intestinal microorganisms and plasma metabolites in portal channels after probiotics feeding. Finally, we combined the results of omics analysis to reveal the mechanism of probiotics on nitrogen metabolism in weaned piglets. The results showed that L. Rhmnosus GG ATCC53103 and L. Plantarum JL01 increased nitrogen apparent digestibility, nitrogen deposition rate, and nitrogen utilization rate of weaned piglets (P < 0.05); the relative expression of mTOR and SK6 mRNA in skeletal muscle increased significantly (P < 0.05). When L. rhamnosus GG ATCC53103 and L. plantarum JL01 were combined, we found that Clostridium and Prevotella significantly increased in the jejunum (P < 0.05). The relative abundance of Lactobacillus, Ruminococcus, Streptococcus, and Prevotella in the ileum increased significantly (P < 0.05). Compared with the control group, L-Tryptophan, 3-Phosphonyloxypyruvate, cis-Aconitate, and Carbamoyl phosphate were significantly increased in the mixed group portal vein. The result of the combinatorial analysis showed that the significantly increased microorganisms could encode the enzyme genes for the synthesis of L-Tryptophan, 3-Phosphonooxypyruvate, cis-Aconitate, and Carbamoyl phosphate. In summary, our results demonstrated that L. Rhamnosus GG ATCC53103 and L. Plantarum JL01 could stimulate the expression of skeletal muscle protein synthesis genes of weaned piglets by modulating the structure of the gut microbiota and its metabolites, thereby improving nitrogen metabolism in weaned piglets.

BackgroundThis study aimed to explore the feasibility and safety of single-incision plus one-port laparoscopic total gastrectomy (SITG + 1) with Overlap esophagojejunostomy (SITG + 1-Overlap) and to share preliminary experiences.MethodsThis retrospective study included 10 patients with gastric cancer located in the cardia or body who underwent SITG + 1-Overlap between August 2020 and October 2021.The demographics, tumor characteristics, postoperative outcomes, and short-term complications of all the enrolled patients were summarized and statistically analyzed. Data were expressed as mean ± standard deviation (SD) if they were normally distributed. Otherwise, Median (Quartile1, Quartile3) was used.ResultsIn the collective perioperative data of these 10 patients who underwent radical gastrectomy, the median of the length of transumbilical incision and blood loss were 3.0 cm and 100.0 ml respectively, and the mean operation time and 385.5 ± 51.6 min. Postoperative data indicated that the gastric tube was removed on 2.0 (2.0, 3.0) days, and the timing of first feeding, activity, flatus, and defecation was 1.5 (1.0, 2.0) days, 2.0 (2.0, 2.0) days, 3.0 (2.0, 3.0) days, and 3.8 ± 0.6 days, respectively. The timing of drainage tube removal was 4.6 ± 1.0 days after operation. The duration of hospital stay was 7.5 ± 1.2 days and the VAS pain scores for the 3 days following surgery were 3.0 (2.0, 3.3), 2.0 (2.0, 3.0), and 1.5 (1.0, 2.0) respectively. The mean number of retrieved lymph nodes was 30.7 ± 13.2. Most biochemical indicators gradually normalized with the recovery of the patients after surgery. No 30-day postoperative complications were noted.ConclusionsFor the first time, our preliminary data indicate the feasibility and safety of Overlap esophagojejunostomy in SITG + 1 surgery. This modified Overlap procedure has the potential to simplify the reconstruction procedure and lower the technical challenge of SITG + 1 radical gastrectomy for cardia or upper gastric cancer in the early and advanced stages.

ABSTRACT: In recent years, clinical cases of inclusion body hepatitis (IBH) and hydropericardium syndrome (HPS) have been emerging and increasing in chicken flocks worldwide. Mixed infections with 2 or more fowl adenovirus (FAdV) serotypes were common in these cases. Herein, we collected a clinical sample that was positive for FAdV from 40-day-old broilers with IBH and HPS symptoms in Shandong province of China and determined the complete genome of FAdVs on the Illumina HiSeq4000 platform. The results showed that the sample contained 2 FAdV strains of D species and C species and named SD1763-1 and SD1763-2 respectively. The genome of SD1763-1 strain was 43,913 nt in length, with a G+C content of 53.51%, whereas SD1763-2 strain was 43,721 nt in length, with a G+C content of 54.87%. Sequence alignment and phylogenetic analysis revealed that strain SD1763-1 was clustered together with serotype 2/11 of FAdV-D, and SD1763-2 was clustered together with FAdV-4. There is no recombination between the genomes of the 2 viruses of FAdV-D and FAdV-C in the present study. This is the first report of obtaining 2 genomic sequences of FAdV strains simultaneously by direct use of deep sequencing in one clinical individual chicken sample, which provided direct evidence for mixed infections of adenovirus serotypes in the clinic and enriched the genome data to explore the geographic biomarkers and virulence signatures of the genus Aviadenovirus.

Titanium alloys are difficult-to-machine materials that exhibit a low machining efficiency, yielding its restricted applications. The combination of micro-textures and a cemented carbide surface cutter can effectively improve the cutting performance and enhance titanium alloys' machining quality. Therefore, this manuscript investigates a cemented carbide ball-end milling cutter with surface modifications. Firstly, we prepared micro-textures with a variable distribution density on the surface of a cemented carbide cutter and revealed its properties from the microscopic aspect based on the simulation and test methods. Secondly, a milling test was done to reveal the anti-wear and anti-friction properties accuracy. Finally, based on the test data, the Lasso regression prediction models were established. Based on the Matlab particle swarm optimization algorithm, the parameters of micro-textures with a variable distribution density were optimized.

SC9-2 is a recombinant Marek's disease virus (MDV) strain lacking the meq oncogene. Previous study demonstrated that SC9-2 virus provides good protection against challenge with a very virulent MDV rMd5, but it induces immunosuppressive effects in specific pathogen-free (SPF) chickens. In the present study, SC9-2 was serially passaged on chicken embryo fibroblast (CEF) cell cultures. The pathogenicity and immune efficacy of SC9-2/10th and SC9-2/40th against rMd5 were evaluated. Animal experimental results showed that SC9-2/10th and SC9-2/40th showed no lethality or tumorigenicity in SPF chickens. Body weight of chickens inoculated with SC9-2/40th were significantly higher than that of the chickens inoculated with SC9-2/10th but lower than that of the uninoculated controls. The severity of bursa and thymus atrophy (BTA) and spleen enlargement in SC9-2/40th-inoculated chickens were also weaker than the SC9-2/10th-inoculated ones but stronger than the uninoculated controls. Chickens inoculated with SC9-2/40th and SC9-2/10th showed similar antibody levels induced by H9N2 subtype avian influenza virus/Newcastle disease virus inactivated vaccines, both of which were lower than the uninoculated controls. Replication of SC9-2/40th was significantly lower than SC9-2/10th in feather follicle epithelium (FFE) of infected chickens. The immune protection index of SC9-2/40th was also lower than that of SC9-2/10th, but the difference was not significantly, and both of which were significant higher than that of the commercial MDV vaccine CVI988/Rispens. The results of our studies demonstrated that SC9-2/40th showed weaker severity of BTA, spleen enlargement, and body weight loss and lower replication level in FFE than SC9-2/10th in SPF chickens. However, SC9-2/40th was able to confer better immune protection as compared with CVI988/Rispens vaccination in SPF chickens. In conclusion, serially attenuation of SC9-2 in CEFs reduced the lymphoid organ atrophy and replication in SPF chickens, and the immune protective efficacy of attenuated viruses was still superior than CVI988/Rispens.

Distribution of methylsiloxanes in environment is still far from being well studied. Little is known about the concentrations and associated risks of these chemicals in river-lake systems. This study investigated the occurrence of twelve methylsiloxanes (D4–D6, L5–L13) in the sediments from Lake Chaohu and its inflowing rivers, China, and found the total concentrations (ng/g dry weight) were in the range of 47.1–496 and 239–3593, respectively. Linear congeners were dominant, representing a median of 62.8% and 58.7% of the total concentrations found in the lake and its inflowing rivers, respectively. In general, the concentrations of sediment methylsiloxanes in the investigated river-lake system were low to moderate, compared with the results reported previously in other waters. Source assessment indicated that the emissions from industrial activities and the use of silicone-containing products were the main contributors of sediment methylsiloxanes in the investigated waters. D4 and D5 in 18.5% and 11.1% of river sediment samples might pose ecological risks to fish. The risks from the linear congeners in sediments in the area were not estimated due to no related benchmarks available. More studies are needed to investigate the occurrence of these chemicals and associated risks in aquatic environment.

Avian leukosis virus (ALV) continues evolving to obtain new genomic characters to enhance its pathogenicity. In the present study, an ALV-J strain LH20180301 was isolated from broiler breeder chickens that reached the speak of paralyzation before 20-week-old. The necropsy chickens showed subcutaneous and muscular hemorrhage, and developed tumors in multiple organs including bone, liver, spleen, and kidney. The complete provirus was then cloned and sequenced to investigate the molecular characteristics and oncogenicity etiology of this virus associated with the outbreak of disease. The genomic structure of the reported ALV-J strain LH20180301 was highly conservative with other ALVs. Recombination events between the virus with endogenous virus were identified in the viral genome. Compared with the ALV-J original HPRS-103 strain, the major recombination sites of the viral genome with ev-1 were located in 5′ UTR-gag and 3′ UTR regions. Phylogenetic analysis of group specific antigen gp85 encoding protein showed that the LH20180301 branched with ALV-J prevalent in “yellow chickens” of local breeds in South China. Nine amino acids (N58, D60, K70, A71, K108, N112, N113, N121, R272) in the gp85 were highly conserved among ALV-J isolates before 2012, but various mutations were found in the late isolates including LH20180301. In addition, the LH20180301 strain also had the same deletion pattern of 3′ UTR with them. Therefore, LH20180301 might derive from the same ancestor with those viruses and may be the trend of ALV-J evolution in China. The defined new genomic characters in the gp85 and 3′ UTR region of ALV-J might provide the molecular basis for its enhanced oncogenicity.

When precision cutting titanium alloy, the cutting part of cutting tool is mainly concentrated in the cutting edge area, so there is a strong emphasis upon the cutting edge’s geometric parameters. Studies have found that putting a micro-texture on the cutting surface can reduce the cutting force. This article looks at the milling force involved in cutting titanium alloy with a micro-textured ball-end milling cutter with different shaped cutting edges. First, a milling model relating to different cutting edges is established based on the traditional model of milling force. Then, the effects of different cutting edge geometry parameters and micro-texture parameters on milling force are simulated and tested using a finite element method. With milling force serving as the evaluation index, the optimum micro-texture parameters for a blunt circular cutting edge are a micro-pit diameter of 40 μm, a distance between micro-pits of 175 μm, a distance from the cutting edge of 110 μm, and a blunt circle radius of 60 μm. For a negative chamfer edge, the optimum parameters were a micro-pit diameter of 50 μm, a distance between micro-pits of 175 μm, a distance from the cutting edge of 120 μm, an edge width of 200 μm, and an edge angle of 10°.

This experimental study presents the rheological properties and strength characteristics of cemented unclassified tailings backfill (CUTB). The particle size distribution and chemical properties of tailings from the Shizhuyuan lead-zinc mine were examined experimentally. A series of rheological properties and uniaxial compressive strength (UCS) tests were conducted to study the relations between the rheological properties of CUTB and two factors of cement-tailings ratio (c/t) and solid content (SD). The two-factor nonrepetitive analysis of variance (ANOVA) method was used to study the sensitivity of rheological properties to two factors of c/t and SD. Relations between UCS performance of CUTB and c/t, SD, and curing time (CT) were discussed. Results indicate that CUTB samples exhibit obvious shear thinning characteristics and the rheological process is the result of multiple rheological model composites. Yield stress and viscosity of CUTB increase with the increase of SD and c/t as quadratic. The solid content is the most important factor for the rheological properties of CUTB, followed by c/t. UCS of CUTB increases exponentially with the increase of SD and increases with c/t as quadratic. The larger the ratio of c/t, the greater the influence of the CT on the increasing strength of CUTB. The smaller the c/t, the slower the increase of the CUTB’s strength with the increase of the SD. The findings of this study can provide the efficient mix proportion of backfill slurry for the backfill mining design, so as to have better performance of the underground mining structure and reduce the cost of backfill mining.

GX0101 is the first field Marek’s disease virus (MDV) recombinant with an REV LTR insert isolated in China. We speculated that there was a selective advantage of GX0101 becoming the more prevalent field strain from a very low percentage of recombinant virus. In the study, dual fluorescence quantitative real-time PCR (DF-qPCR) that detects GX0101 and GX0101ΔLTR simultaneously was established based on the genomic difference of GX0101 and its LTR deletion strain GX0101ΔLTR. MDV natural transmission was simulated in specific-pathogen-free (SPF) chicks, and continuous tracking of GX0101 and GX0101ΔLTR in chicks was carried out. The results showed that GX0101 possessed high horizontal transmission capacity, which could infect SPF chicks by contact in a short time and became the predominant strain following contact infections in chicken flocks. GX0101 still had a more significant advantage of horizontal transmission than GX0101ΔLTR after continuous passage even if the initially infectious dose was significantly lower. There were 72 differentially expressed MDV genes between GX0101 and GX0101ΔLTR, with the genes and gene products mainly involved in virus replication, tegument protein, glycoprotein, nucleocapsid protein, immune evasion, tumor development and/or pathogenesis, and hypothetical protein. Sixteen genes related to virus replication and transmission were significantly up-regulated. This is the first study to illuminate that increased horizontal transmission of recombinant MDV due to REV LTR was the competitive advantage of the virus being a prevalent strain and define the differential transcription profile of viral genes between GX0101 and GX0101ΔLTR. This will be helpful for in-depth study on the molecular mechanism of increased horizontal transmission of MDV by REV LTR.

The electronic interaction between metal and supports can regulate the activity of heterogeneous nanomaterials. We designed four supported Pd catalysts (Pd/ZnO, Pd/TiO2, Pd/Al2O3 and Pd/SiO2) for the electrocatalytic activity toward the formic acid oxidation reaction (FAOR). The electrochemical results demonstrate that Pd/ZnO exhibits superior electrocatalytic activity toward FAOR, which can be attributed to the decreased electron density of ZnO-supported Pd nanoparticles, as further confirmed by X-ray photoelectron spectroscopic characterization and CO stripping electrochemical measurement. This study provides an effective method for the design of high-efficiency electrocatalysts, which could be also useful for studying the surface electronics of supported metal-nanoparticle. Keywords: Electronic metal–support interaction, Pd nanoparticles, Electron density, Formic acid oxidation reaction, Electrocatalysis

Subway systems consume a large amount of energy each year. How to reduce the energy consumption of subway systems has already become an issue of concern in recent years. This paper proposes an energy-efficient approach to reduce the traction energy by optimizing the train operation for multiple interstations. Both the trip time and driving strategy are considered in the proposed optimization approach. Firstly, a bi-level programming model of multiple interstations is developed for the energy-efficient train operation problem, which is then converted into an integrated model to calculate the driving strategy for multiple interstations. Additionally, the multi-population genetic algorithm (MPGA) is used to solve the problem, followed by calculating the energy-efficient trip times. Finally, the paper presents some examples based on the operation data of the Beijing Changping subway line. The simulation results show that the proposed approach presents a better energy-efficient performance than that with only optimizing the driving strategy for a single interstation.

The simulation of railway systems plays a key role in designing the traction power supply network, managing the train operation, and making changes to timetables. Various simulation technologies have been developed to study the railway traction power network and train operation independently. However, the interactions between the load performance, train operation, and fault conditions are not fully understood. This paper proposes a mathematical modeling method to simulate the railway traction power network with a consideration of a multi-train operation, driving controls, under-voltage traction, and substation fault modes. The network voltage, power load demands, and energy consumption according to the existing operation are studied. The hotspots of the power supply network are identified based on an evaluation of the train operation and power demand. The impact of traction power substation (TPSS) outage and a short circuit on the power supply network have been simulated and analyzed. The simulation results have been analyzed and compared with those of a normal operation. A case study based on a practical metro line in Singapore is developed to illustrate the power network evaluation performance.

H9N2 subtype avian influenza virus (AIV) is widely prevalent in poultry, and the virus is becoming adaptive to mammals, which poses pandemic importance. Here, BALB/c mice were employed as a model to evaluate the adaption in mammals of 21 field H9N2 viruses isolated from avian species between 2016 to 2019 in China. The replication capacity of the viruses was evaluated in the lungs of mice. The pathogenicity of the viruses were compared by weight loss and lung lesions from infected mice. The whole genomic sequences of the viruses were further characterized to define the associated phenotypes of the H9N2 viruses in vitro and in vivo. The results showed that most viruses could replicate well and cause lesions in the mouse lungs. The propagation capacity in MDCK cells and damage to respiratory tissues of the infected mice corresponded to relative viral titers in the mouse lungs. Further genome analysis showed that all of the H9N2 viruses belonged to the same genotype, G57, and contained a couple of amino acid substitutions or deletions that have been demonstrated as avian-human markers. Additionally, nine amino acids residues in seven viral proteins were found to be correlated with the replication phenotypes of the H9N2 viruses in mammals. The study demonstrated that a well-defined H9N2 AIV genotype with high adaption in mammals was prevalent in China in recent years. Further investigations on the role of the identified residues and continuous surveillance of newly identified mutations associated with host adaption should be strengthened to prevent any devastating human influenza pandemics.

A high temperature is produced in the process of precision milling of titanium alloy, and the cutting temperature can be effectively reduced by placing a micro-texture on the tool surface. In order to study the milling temperature of micro-textured ball-end milling cutter in milling titanium alloy under the combined action of a blunt radius with different edges and a micro-texture with different parameters, a new method based on micro-element theory and the generation and transmission of cutting heat has been established. At the same time, the influence of different radii of blunt edges on the milling temperature is simulated by the finite element method and experimentally verified to explore the influence of different radii of a blunt edge and micro-texture parameters on the milling temperature. Taking the milling temperature as the evaluation index, the optimum parameters of micro-circular pit texture are as follows: the diameter of micro-circular pit is 40 micron, pit spacing is 225 micron, distance from cutting edge is 100 microns, and radius of the blunt edge is 60 microns.

This paper investigates the identification problem for a class of input nonlinear systems whose disturbance is in the form of the moving average model. In order to improve the computation complexity, the key term separation principle is introduced to avoid the redundant parameter estimation. Based on the decomposition technique, a hierarchical Newton iterative identification method combining the key term separation principle is proposed for enhancing the estimation accuracy and handling the computational load with the presence of the high dimensional matrices. In the identification procedure, the unknown internal items or vectors are replaced with their iterative estimates. The effectiveness of the proposed identification methods is shown via a numerical simulation example.

In urban rail transit systems, train scheduling plays an important role in improving the transport capacity to alleviate the urban traffic pressure of huge passenger demand and reducing the operation costs for operators. This paper considers the train scheduling with short turning strategy for an urban rail transit line with multiple depots. In addition, the utilization of trains is also taken into consideration. First, we develop a mixed integer nonlinear programming (MINLP) model for the train scheduling, where short turning train services and full-length train services are optimized based on the predefined headway obtained by the passenger demand analysis. The MINLP model is then transformed into a mixed integer linear programming (MILP) model according to several transformation properties. The resulting MILP problem can be solved efficiently by existing solvers, e.g., CPLEX. Two case studies with different scales are constructed to assess the performance of train schedules with the short turning strategy based on the data of Beijing Subway line 4. The simulation results show that the reduction of the utilization of trains is about 20.69%.

Marek’s disease (MD) has been occurring with increasing frequency in chickens in recent years. To our knowledge, however, there has been no report of the very virulent plus (vv+) MD virus (MDV) field isolate in China. Studies have shown that dual infection with immunosuppressive viruses such as chicken infectious anemia virus (CIAV) occurs frequently in chickens developing MD. In this study, we performed a designed set of in vivo experiments, which comprised five different groups of chickens, including the group of CVI988/Rispens-vaccinated chickens, the groups of CVI988/Rispens-vaccinated chickens infected with MDV or CIAV or both viruses (MDV and CIAV), and the group of MDV-challenged chickens. The effects of CIAV dual infection on the immunization of commercial MDV vaccine CVI988/Rispens were evaluated. The results show that infection of the SD15 strain of CIAV significantly reduced the weight and antibody titers to avian influenza virus (AIV)/Newcastle disease virus (NDV) inactivated vaccines of chickens immunized with the CVI988/Rispens, and resulted in the atrophy of thymus/bursa and the enlargement of spleen. The CVI988/Rispens vaccination conferred good immune protection for chickens challenged with 2000 PFU of the GX0101 strain of MDV. However, dual infection with SD15 significantly reduced the body weight, antibody titers induced by AIV/NDV inactivated vaccines and protective index of CVI988/Rispens, and resulted in the aggravation of the immunosuppression, mortality, and viremia of GX0101 in CVI988/Rispens-immunized/GX0101-challenged chickens. Overall, CIAV infection significantly reduced the protective effects of the CVI988/Rispens vaccine against MDV, implying that concurrent infection with CIAV may be a major contributor in the frequent attacks of MD in China in recent years.

Increasing attention is being paid to the energy efficiency in metro systems to reduce the operational cost and to advocate the sustainability of railway systems. Classical research has studied the energy-efficient operational strategy and the energy-efficient system design separately to reduce the traction energy consumption. This paper aims to combine the operational strategies and the system design by analyzing how the infrastructure and vehicle parameters of metro systems influence the operational traction energy consumption. Firstly, a solution approach to the optimal train control model is introduced, which is used to design the Optimal Train Control Simulator(OTCS). Then, based on the OTCS, the performance of some important energy-efficient system design strategies is investigated to reduce the trains’ traction energy consumption, including reduction of the train mass, improvement of the kinematic resistance, the design of the energy-saving gradient, increasing the maximum traction and braking forces, introducing regenerative braking and timetable optimization. As for these energy-efficient strategies, the performances are finally evaluated using the OTCS with the practical operational data of the Beijing Yizhuang metro line. The proposed approach gives an example to quantitatively analyze the energy reduction of different strategies in the system design procedure, which may help the decision makers to have an overview of the energy-efficient performances and then to make decisions by balancing the costs and the benefits.