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Background: Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disease, of which diarrhea-predominant irritable bowel syndrome (IBS-D) is a common subtype. In China, acupoint application therapy is widely used as an effective complementary therapy for IBS-D treatment. For clinical management, currently acupoint application is usually combined with other therapies (including acupuncture, moxibustion, Chinese herbal medicine and western medicine, etc.) for treating IBS-D; however, to date, evidence demonstrating the most effective options for treating different manifestations of IBS-D is insufficient. Therefore, this protocol proposes a systematic review and network meta-analysis (NMA) for evaluating the effectiveness of acupoint application and its combination therapies in terms of preventing the onset of IBS-D. Objective: To analyze the medication rules and mechanism of action concerning patented CHF in the intervention of SS, and to provide review findings which serve as an add-on reference for treating patients with SS. Methods: Four English electronic databases (PubMed, Web of Science, the Cochrane Library, and EMBASE) and four Chinese databases (CNKI, CQVIP, WanFang, and CBM) from their inception onwards will be searched for published and unpublished randomized controlled trials (RCTs), in an effort to evaluate the efficacy and safety of acupoint application therapy and its combination therapies for patients with IBS-D. Stata version 14.0 software packages will be used for meta-analysis. A Bayesian NMA will be performed using the R version 4.0.2 and Aggregate Data Drug Information System (ADDIS version 1.16.8) software packages. Bias risk will be accessed via Cochrane Collaboration’s risk of bias test; more specifically, publication bias will be evaluated using Egger’s test and funnel plots. The probabilities of interventions of each preventive intervention for various outcomes will be calculated, clustered and ranked using the cumulative ranking curve method. The GRADE method will be used to assess the certainty of evidence from NMA outcomes. Results: The results of this study will be submitted to, reviewed by, and, following appropriate revisions, published in peer-reviewed periodical journals. Conclusion: This study aims at revealing the clinical efficacy of acupoint application therapy and its combined therapy in the treatment of IBS-D, and may provide an evidence-based basis for identifying the best acupoint application program.

Fault-tolerant quantum computing based on surface code has emerged as an attractive candidate for practical large-scale quantum computers to achieve robust noise resistance. To achieve universality, magic states preparation is a commonly approach for introducing non-Clifford gates. Here, we present a hardware-efficient and scalable protocol for arbitrary logical state preparation for the rotated surface code, and further experimentally implement it on the \textit{Zuchongzhi} 2.1 superconducting quantum processor. An average of \hhl{$0.8983 \pm 0.0002$} logical fidelity at different logical states with distance-three is achieved, \hhl{taking into account both state preparation and measurement errors.} In particular, \hhl{the magic states $|A^{\pi/4}\rangle_L$, $|H\rangle_L$, and $|T\rangle_L$ are prepared non-destructively with logical fidelities of $0.8771 \pm 0.0009 $, $0.9090 \pm 0.0009 $, and $0.8890 \pm 0.0010$, respectively, which are higher than the state distillation protocol threshold, 0.859 (for H-type magic state) and 0.827 (for T -type magic state).} Our work provides a viable and efficient avenue for generating high-fidelity raw logical magic states, which is essential for realizing non-Clifford logical gates in the surface code., Comment: In this version, we do not employ readout error mitigation strategies (in the previous version, we use readout transition matrix to mitigate the measurement error) to remove measurement errors because we believe it provides a more predictive assessment of the actual fidelity when generating and consuming magic states for a non-Clifford gate, as consuming the state involves measurement

Additional file 1.

Sterically encumbering m-terphenyl isocyanides are a class of metal-binding group that foster low-coordinate metal-center environments in coordination chemistry by exerting considerable intermolecular steric pressures between neighboring ligands. In the context of metal surfaces, the encumbering steric properties of the m-terphenyl isocyanides are shown to weaken the interaction between the metal-binding group and a planar substrate, leading to a preference for molecular adsorption at sites with convex curvature, such as the step edges and herringbone elbow sites on Au(111). Here, we investigate the site-selective binding of individual m-terphenyl isocyanide ligands on a Au(111) surface through scanning tunneling microscopy (STM) and inelastic electron tunneling spectroscopy (IETS). The site-dependent steric pressure alters the vibrational fingerprint of the m-terphenyl isocyanides, which is characterized with single-molecule precision through joint experimental and theoretical approaches. This study for the first time provides molecular-level insights into the steric-pressure-enabled surface binding selectivity as well as its effect on the chemical properties of individual m-terphenyl isocyanide ligands, thereby highlighting the potential to control the physical and chemical properties of metal surfaces through tailored ligand design.

Aluminum alloy 6061 was welded with zinc coated low carbon steel by cold metal transfer (CMT). The microstructure composition, morphology and growth process of the welding joint and the HAZ were researched. The weld area on the side of the galvanized steel sheet mainly contains Fe2Al5. And on the side of the aluminum alloy substrate, it is mainly filled with a needle-like FeAl3. At the same time, Al8Fe2Si is formed at the edge of FeAl3. The zinc-rich region on the side of the aluminum alloy mainly contains an aluminum-zinc solid solution and an aluminum-zinc co-crystal, and the current size had no significant effect on the type and morphology of the compounds produced in the interface layer.

The mechanical properties of 2060 and 2099 T-joints welded by double-sided laser beam welding were analyzed in this experiment. Various mechanical tests were performed to determine the transverse tensile properties of the region perpendicular to the weld, the tensile properties of the skin and stringer, the compressive properties of the region parallel to the weld seam, and the fatigue properties perpendicular to the weld seam. The T-joint was found to consist of the base metal, partial melting zone, equiaxed zone (EQZ), columnar crystal zone, and cellular dendritic zone from the base metal to the center of the weld seam. The EQZ was proved to be the weak area during mechanical properties tests of the T-joint. Moreover, the welding penetration had a great influence on the transverse tensile properties and weak areas were located in the EQZ near the lower fusion line. The EQZ near the upper fusion line was the weak area in the process of compression. In addition, severe porosities and cracks greatly influenced the mechanical properties of the joint. The fatigue property was closely related to the deformation angle; the fatigue source was located at the weld toe, and the crack propagation was along the base metal.

Cold metal transfer plus pulse (C + P) arc was applied in the additive manufacturing of 4043 Al alloy parts. Parameters in the manufacturing of the parts were investigated. The properties and microstructure of the parts were also characterized. Experimental results showed that welding at a speed of 8 mm/s and a wire feeding speed of 4.0 m/min was suitable to manufacture thin-walled parts, and the reciprocating scanning method could be adopted to manufacture thick-walled parts. The thin-walled parts of the C + P mode had fewer pores than those of the cold metal transfer (CMT) mode. The thin- and thick-walled parts of the C + P mode showed maximum tensile strengths of 172 and 178 MPa, respectively. Hardness decreased at the interface and in the coarse dendrite and increased in the refined grain area.

Classifying many-body quantum states with distinct properties and phases of matter is one of the most fundamental tasks in quantum many-body physics. However, due to the exponential complexity that emerges from the enormous numbers of interacting particles, classifying large-scale quantum states has been extremely challenging for classical approaches. Here, we propose a new approach called quantum neuronal sensing. Utilizing a 61 qubit superconducting quantum processor, we show that our scheme can efficiently classify two different types of many-body phenomena: namely the ergodic and localized phases of matter. Our quantum neuronal sensing process allows us to extract the necessary information coming from the statistical characteristics of the eigenspectrum to distinguish these phases of matter by measuring only one qubit. Our work demonstrates the feasibility and scalability of quantum neuronal sensing for near-term quantum processors and opens new avenues for exploring quantum many-body phenomena in larger-scale systems., Comment: 7 pages, 3 figures in the main text, and 13 pages, 13 figures, and 1 table in supplementary materials

Supplemental material, sj-doc-4-taj-10.1177_20406223221077966 for Is Chinese herbal formula (nourishing Yin therapy) effective and well tolerated as an adjunct medication to hydroxychloroquine in the treatment of primary Sj��gren���s syndrome? A meta-analysis of randomised controlled trials by Shaowei Li, Rui Ou, Dandan Liu, Zhihuang Chen, Song Wei, Xiaohao Li, Xianxian Zhang, Yingwan Liu and Chunfu Hou in Therapeutic Advances in Chronic Disease

Additional file 1: Table S1. Epitope binning of spike nanobodies. Table S2. Cryo-EM data collection, refinement and validation statistics. Table S3. Conservation of epitopic residues in RBD for C5G2 binding from natural occurring SARS-Cov-2 variants.

Supplemental material, sj-doc-1-taj-10.1177_20406223221077966 for Is Chinese herbal formula (nourishing Yin therapy) effective and well tolerated as an adjunct medication to hydroxychloroquine in the treatment of primary Sj��gren���s syndrome? A meta-analysis of randomised controlled trials by Shaowei Li, Rui Ou, Dandan Liu, Zhihuang Chen, Song Wei, Xiaohao Li, Xianxian Zhang, Yingwan Liu and Chunfu Hou in Therapeutic Advances in Chronic Disease

Supplemental material, sj-doc-3-taj-10.1177_20406223221077966 for Is Chinese herbal formula (nourishing Yin therapy) effective and well tolerated as an adjunct medication to hydroxychloroquine in the treatment of primary Sj��gren���s syndrome? A meta-analysis of randomised controlled trials by Shaowei Li, Rui Ou, Dandan Liu, Zhihuang Chen, Song Wei, Xiaohao Li, Xianxian Zhang, Yingwan Liu and Chunfu Hou in Therapeutic Advances in Chronic Disease

Supplemental material, sj-doc-2-taj-10.1177_20406223221077966 for Is Chinese herbal formula (nourishing Yin therapy) effective and well tolerated as an adjunct medication to hydroxychloroquine in the treatment of primary Sj��gren���s syndrome? A meta-analysis of randomised controlled trials by Shaowei Li, Rui Ou, Dandan Liu, Zhihuang Chen, Song Wei, Xiaohao Li, Xianxian Zhang, Yingwan Liu and Chunfu Hou in Therapeutic Advances in Chronic Disease

Transition metal dichalcogenide moiré heterostructures provide an ideal platform to explore the extended Hubbard model1, where long-range Coulomb interactions play a critical role in determining strongly correlated electron states. This has led to experimental observations of Mott insulator states at half filling2–4 as well as a variety of extended Wigner crystal states at different fractional fillings5–9. However, a microscopic understanding of these emerging quantum phases is still lacking. Here we describe a scanning tunnelling microscopy (STM) technique for the local sensing and manipulation of correlated electrons in a gated WS2/WSe2 moiré superlattice, which enables the experimental extraction of fundamental extended Hubbard model parameters. We demonstrate that the charge state of the local moiré sites can be imaged by their influence on the STM tunnelling current. In addition to imaging, we are also able to manipulate the charge state of correlated electrons. When we ramp the bias on the STM tip, there is a local discharge cascade of correlated electrons in the moiré superlattice, which allows us to estimate the nearest-neighbour Coulomb interaction. Two-dimensional mapping of the moiré electron charge states also enables us to determine the on-site energy fluctuations at different moiré sites. Our technique should be broadly applicable to many semiconductor moiré systems, offering a powerful tool for the microscopic characterization and control of strongly correlated states in moiré superlattices.

Moiré superlattices in transition metal dichalcogenide (TMD) heterostructures can host novel correlated quantum phenomena due to the interplay of narrow moiré flat bands and strong, long-range Coulomb interactions1-9. However, microscopic knowledge of the atomically reconstructed moiré superlattice and resulting flat bands is still lacking, which is critical for fundamental understanding and control of the correlated moiré phenomena. Here we quantitatively study the moiré flat bands in three-dimensional (3D) reconstructed WSe2/WS2 moiré superlattices by comparing scanning tunnelling spectroscopy (STS) of high-quality exfoliated TMD heterostructure devices with ab initio simulations of TMD moiré superlattices. A strong 3D buckling reconstruction accompanied by large in-plane strain redistribution is identified in our WSe2/WS2 moiré heterostructures. STS imaging demonstrates that this results in a remarkably narrow and highly localized K-point moiré flat band at the valence band edge of the heterostructure. A series of moiré flat bands are observed at different energies that exhibit varying degrees of localization. Our observations contradict previous simplified theoretical models but agree quantitatively with ab initio simulations that fully capture the 3D structural reconstruction. Our results reveal that the strain redistribution and 3D buckling in TMD heterostructures dominate the effective moiré potential and the corresponding moiré flat bands at the Brillouin zone K points.

Gallium-based liquid metal (GBLM) was added into grease with different proportions and homogenized through mechanical agitation and ball milling. The tribological properties of pure GBLM, pure greases and GBLM as an additive in lithium greases have been investigated by four-ball test. Results showed that pure GBLM exhibited poor anti-wear performance under low load, and the lubricating performance of greases under high load was not satisfactory. After GBLM was added to the grease, the extreme pressure lubrication capacity of the latter was effectively increased, whereas the anti-wear performance under low load did not decrease. When the mass ratio of GBLM to specific commercial lithium grease reached 1:1, the weld load was over 10 kN, which was the maximum value for greases.

Transition metal dichalcogenide (TMD) moir�� heterostructures provide an ideal platform to explore the extended Hubbard model1 where long-range Coulomb interactions play a critical role in determining strongly correlated electron states. This has led to experimental observations of Mott insulator states at half filling2-4 as well as a variety of extended Wigner crystal states at different fractional fillings5-9. Microscopic understanding of these emerging quantum phases, however, is still lacking. Here we describe a novel scanning tunneling microscopy (STM) technique for local sensing and manipulation of correlated electrons in a gated WS2/WSe2 moir�� superlattice that enables experimental extraction of fundamental extended Hubbard model parameters. We demonstrate that the charge state of local moir�� sites can be imaged by their influence on STM tunneling current, analogous to the charge-sensing mechanism in a single-electron transistor. In addition to imaging, we are also able to manipulate the charge state of correlated electrons. Discharge cascades of correlated electrons in the moir�� superlattice are locally induced by ramping the STM bias, thus enabling the nearest-neighbor Coulomb interaction (UNN) to be estimated. 2D mapping of the moir�� electron charge states also enables us to determine onsite energy fluctuations at different moir�� sites. Our technique should be broadly applicable to many semiconductor moir�� systems, offering a powerful new tool for microscopic characterization and control of strongly correlated states in moir�� superlattices.

The Wigner crystal state, first predicted by Eugene Wigner in 1934, has fascinated condensed matter physicists for nearly 90 years2-14. Studies of two-dimensional (2D) electron gases first revealed signatures of the Wigner crystal in electrical transport measurements at high magnetic fields2-4. More recently optical spectroscopy has provided evidence of generalized Wigner crystal states in transition metal dichalcogenide (TMDC) moir�� superlattices. Direct observation of the 2D Wigner crystal lattice in real space, however, has remained an outstanding challenge. Scanning tunneling microscopy (STM) in principle has sufficient spatial resolution to image a Wigner crystal, but conventional STM measurements can potentially alter fragile Wigner crystal states in the process of measurement. Here we demonstrate real-space imaging of 2D Wigner crystals in WSe2/WS2 moir�� heterostructures using a novel non-invasive STM spectroscopy technique. We employ a graphene sensing layer in close proximity to the WSe2/WS2 moir�� superlattice for Wigner crystal imaging, where local STM tunneling current into the graphene sensing layer is modulated by the underlying electron lattice of the Wigner crystal in the WSe2/WS2 heterostructure. Our measurement directly visualizes different lattice configurations associated with Wigner crystal states at fractional electron fillings of n = 1/3, 1/2, and 2/3, where n is the electron number per site. The n=1/3 and n=2/3 Wigner crystals are observed to exhibit a triangle and a honeycomb lattice, respectively, in order to minimize nearest-neighbor occupations. The n = 1/2 state, on the other hand, spontaneously breaks the original C3 symmetry and forms a stripe structure in real space. Our study lays a solid foundation toward the fundamental understanding of rich Wigner crystal states in WSe2/WS2 moir�� heterostructures.

Additional file 1: Fig. S1. The PCR analysis of the reconstructed E. coli strains. (a) PCR analysis of the constructed E. coli strains with a single copy of the HPV type 11 L1 gene expression cassette integrated at the lpxM, lpxP, pagP, lpxL, eptA, kdsD or gutQ locus of the parental E. coli ER2566 strain. (b) Expression cassettes were constructed for the production ofthe L1 protein from 8 HPV genotypes, and were separately integrated in the kdsD locus of the E. coli ER2566 strain. (c) and (d) The lpxL, lpxM, lpxP, eptA, pagP and gutQ loci were evaluated for the integrated expression of HPV type 18 and 52 L1 genes. The reconstructed E. coli strains were analyzed by PCR. Fig. S2. SDS-PAGE and western blotting analysis of the HPV L1 protein (produced at the shake-flask level). Lanes marked with ���M��� indicate the protein marker. Lanes marked with ���+��� indicate the HPV type 16 L1 protein with high purity, which was used as a positive control. Lanes marked with ���P��� indicate the HPV L1 protein expressed by the E. coli strain utilizing a plasmid-based strategy. Lanes marked with ���Cgene locus��� indicate the HPV L1 protein expressed by the E. coli strain utilizing chromosomally integrated expression strategy. (a) The HPV type 11 L1 protein was, respectively, expressed from the cassette integrated into 7 loci of the ER2566 strain. (b) L1 protein from HPV types 6, 16, 18, 31, 33, 45, 52, and 58 were, respectively, expressed from the cassette integrated into the kdsD locus of the ER2566 strain. (c) and (d) L1 protein from HPV types 18 and 52 were, respectively, expressed from the cassette integrated into 6 loci (as indicated above) of the ER2566 strain. Fig. S3. Evaluation of plasmid maintenance during the three-stage fermentation process. Fig. S4. SDS-PAGE and western blotting analysis of the HPV type 16 L1 protein expressed by the constructed E. coli strains bearing multiple copies of the integrated expression cassette. Lanes marked with ���M��� indicate the protein marker. Lanes marked with ���+��� indicate the HPV type 16 L1 protein with high purity, which was used as a positive control. Fig. S5. Growth curves (a) and transcript levels (b) of the recombinant E. coli strains bearing multiple copies of the HPV16 target gene during large-scale fermentation. The time points were set as 0, 1, and 6 h post-IPTG induction.

Additional file 12: Figure S2. The workflow of CDSs reannotation.

Additional file 13: Figure S3. Pairwise alignment and visualization. Assembly results for each step are assessed by alignment of final sequences back onto the reference genome. The visualization results are quickly achieved by Nucmer.

Additional file 11: Figure S1. The analysis pipeline for genomic re-annotation.

Moir�� superlattices in transition metal dichalcogenide (TMD) heterostructures can host novel correlated quantum phenomena due to the interplay of narrow moir�� flat bands and strong, long-range Coulomb interactions1-5. However, microscopic knowledge of the atomically-reconstructed moir�� superlattice and resulting flat bands is still lacking, which is critical for fundamental understanding and control of the correlated moir�� phenomena. Here we quantitatively study the moir�� flat bands in three-dimensional (3D) reconstructed WSe2/WS2 moir�� superlattices by comparing scanning tunneling spectroscopy (STS) of high quality exfoliated TMD heterostructure devices with ab initio simulations of TMD moir�� superlattices. A strong 3D buckling reconstruction accompanied by large in-plane strain redistribution is identified in our WSe2/WS2 moir�� heterostructures. STS imaging demonstrates that this results in a remarkably narrow and highly localized K-point moir�� flat band at the valence band edge of the heterostructure. A series of moir�� flat bands are observed at different energies that exhibit varying degrees of localization. Our observations contradict previous simplified theoretical models but agree quantitatively with ab initio simulations that fully capture the 3D structural reconstruction. Here the strain redistribution and 3D buckling dominate the effective moir�� potential and result in moir�� flat bands at the Brillouin zone K points.

The ability to regulate the interaction between gold and hydrophilic/hydrophobic surfaces with an external electric field is of great theoretical and practical value for biotechnological applications such as cell recognition and targeted drug delivery. This study explores the interfacial interaction between colloidal probes with different wetting properties and gold surfaces as a function of the electrochemical potential. A three-electrode system is used to control the electrical potential of the gold surface. When a hydrophilic silicon oxide (SiO2) microsphere contacts the gold surface, the interfacial adhesion strengthens with an increase in the applied potential. However, when a hydrophobic polystyrene (PS) microsphere contacts the gold surface, the adhesive force remains almost zero at all potentials. This result is attributed to differences in the potential-dependent interfacial affinity of the Au surface to microspheres of different chemical natures and hence wetting properties. Specifically, the da...

Vapor pressure deficit (VPD) is an important parameter in modelling hydrologic cycles and vegetation productivity. Meteorological stations are scarce in remote areas, which often results in imprecise estimations of VPD on the Tibetan Plateau. Moderate Resolution Imaging Spectroradiometer (MODIS) provides evapotranspiration data, which may offer the possibility of scaling up VPD estimations on the Tibetan Plateau. However, no studies thus far have estimated VPD using MODIS evapotranspiration data on the Tibetan Plateau. Therefore, this study used MODIS potential evapotranspiration (PET) to estimate VPD in alpine meadows, alpine steppes, croplands, forests and shrublands for the year, spring, summer, autumn and winter in 2000–2012. A series of root-meansquared-error (RMSE) and mean-absolute-error (MAE) values were obtained for correlating measured VPD and estimated VPD using MODIS PET data for each listed time period and vegetation type: whole year (0.98–2.15 hPa and 0.68–1.44 hPa), spring (0.95–2.34 hPa and 0.72–1.54 hPa), summer (1.39–2.60 hPa and 0.89–1.96 hPa), autumn (0.78–1.93 hPa and 0.56–1.36 hPa), winter (0.48–1.40 hPa and 0.36–0.98 hPa), alpine steppes (0.48–1.39 hPa and 0.36–1.00 hPa), alpine meadows (0.58–1.39 hPa and 0.44–0.90 hPa), croplands (1.10–2.55 hPa and 0.82–1.74 hPa), shrublands (0.98–1.90 hPa and 0.78–1.37 hPa), and forests (1.40–2.60 hPa and 0.98–1.96 hPa), respectively. Therefore, MODIS PET may be used to estimate VPD, and better results may be obtained if future studies incorporate vegetation types and seasons when the VPD data are estimated using MODIS PET on the Tibetan Plateau.

Highland barley is an important staple food in the Tibet, and the Tibetan Plateau is experiencing obvious climatic warming. However, few studies have examined the warming effects on highland barley growth and biomass allocation under conditions of controlled experimental warming. This limits our ability to predict how highland barley will change as the climate changes in the future. An experiment of field warming at two magnitudes was performed in a highland barley system of the Tibet beginning in late May, 2014. Infrared heaters were used to increase soil temperature. At the end of the warming experiment (September 14, 2014), plant growth parameters (plant height, basal diameter, shoot length and leaf number), biomass accumulation parameters (total biomass, root biomass, stem biomass, leaf biomass and spike biomass), and carbon and nitrogen concentration parameters (carbon concentration, nitrogen concentration, the ratio of carbon to nitrogen concentration in root, stem, leaf and spike) were sampled. The low- and high-level experimental warming significantly increased soil temperature by 1.52 and 1.98 °C, respectively. Average soil moisture was significantly decreased by 0.03 m3 m−3 under the high-level experimental warming, while soil moisture under the low-level experimental warming did not significantly change. The low- and high-level experimental warming did not significantly affect plant growth parameters, biomass accumulation parameters, and carbon and nitrogen concentration parameters. There were also no significant differences of plant growth parameters, biomass accumulation parameters, and carbon and nitrogen concentration parameters between the low- and high-level experimental warming. Our findings suggest that the response of highland barley growth, total and component biomass accumulation, and carbon and nitrogen concentration to warming did not linearly change with warming magnitude in the Tibet.

Monocrystalline silicon is highly promising for applications as semiconductor materials in electronic devices. However, the intrinsic brittleness of Si as well as the relatively low conductivity has restricted its wide application. In this paper, the optimized electronic and mechanical properties of monocrystalline silicon doped with trace content of N or P (SiMx, X = 0, 0.2%, 0.46%, 1.5%, M = N, P) were investigated by first-principles calculations. The results show that the doping of N or P elements can improve the mechanical and electronic properties of monocrystalline silicon, and with the increase of doping concentration, the improving effect becomes more obvious. In addition, the doping of N has a stronger effect on Si than that of P. The doping N, P atoms can form polar covalent bonds to enhance the covalency between atoms, improve the mechanical of Si. Electronic structure analysis shows that the doping of N or P atom makes the hybridization of s-orbital and p-orbital stronger, thus narrows the band gap and improves the conductivity of Si. Furthermore, as the concentration of doping elements increases, Si goes from indirect to direct semiconductor, which is beneficial to improve the recombination of excited electron-hole pairs due to there is no momentum difference between the two positions in k space.

The thick plate narrow gap welding of 25Cr2NiMo1V rotor steel is achieved by metal active gas arc welding, in which the weld gap was 18.04–19.9 mm. After welding, the weldment was heat treated at 580 °C (20 h). The impact and tensile properties in the as-welded and heat-treated were studied. The results show that after heat treatment, the coarse carbides in the center of the weld were transformed into fine granular carbides distributed along the grain boundaries, and the quantity of carbide precipitates in the weld near the fusion line was reduced. The tensile fracture mode changed from a ductile fracture to a combination of brittle and ductile fractures, and the tensile strength of the weld metal changed from 605 MPa to 543 MPa. After heat-treated, the radiation zone of the weld center changed from a brittle fracture to a combination of brittle and ductile fractures, and the impact energy changed from 141 J to 183 J, the characteristics of the brittle fracture in the radial zone of the fusion line were more obvious, and the impact energy changed from 113 J to 95 J. Therefore, after heat treatment, the toughness of the welded metal was improved, without reducing the strength and hardness of the welded metal to a large extent.

Accurate quantification of aboveground biomass of grasslands in alpine regions plays an important role in accurate quantification of global carbon cycling. The monthly normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), mean air temperature (Ta), ≥5°C accumulated air temperature (AccT), total precipitation (TP), and the ratio of TP to AccT (TP/AccT) were used to model aboveground biomass (AGB) in grasslands on the Tibetan Plateau. Three stepwise multiple regression methods, including stepwise multiple regression of AGB with NDVI and EVI, stepwise multiple regression of AGB with Ta, AccT, TP and TP/AccT, and stepwise multiple regression of AGB with NDVI, EVI, Ta, AccT, TP and TP/AccT were compared. The mean absolute error (MAE) and root mean squared error (RMSE) values between estimated AGB by the NDVI and measured AGB were 31.05 g m-2 and 44.12 g m-2, and 95.43 g m-2 and 131.58 g m-2 in the meadow and steppe, respectively. The MAE and RMSE values between estimated AGB...

This paper investigates the continuous robust fixed-time control for the double integrator system with matched disturbance. A new integral-type sliding mode (ISM) fixed-time controller is proposed that can significantly alleviate the chattering phenomenon and ensure the states of double integrator system to converge to the origin within a fixed settling time. Continuous Lyapunov functions are given and a valid proof for the closed loop system is presented based on the bi-limit homogeneous theorem. An output feedback ISM fixed-time controller is also developed for the disturbed double integrator system based on a fixed-time observer. Numerical simulations are provided to demonstrate the performance of proposed continuous robust fixed-time algorithms.

The nutritional quality of grasslands is closely related to recruitment of young and population dynamics of livestock and wild herbivores. However, the response of nutritional quality to climate warming has not been fully understood in the alpine meadow on the Tibetan Plateau, especially in the Northern Tibet. Here, we investigated the effect of experimental warming (beginning in 2008) on nutritional quality in three alpine meadows (site A: 4313 m, B: 4513 m and C: 4693 m) in the Northern Tibet. Crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), crude ash (Ash), ether extract (EE) and water-soluble carbohydrate (WSC) were examined in 2018–2019. Experimental warming only increased the content of CP by 27.25%, ADF by 89.93% and NDF by 41.20%, but it decreased the content of Ash by 57.76% in 2019 at site B. The contents of CP and WSC both increased with soil moisture (SM). The content of CP decreased with vapor pressure deficit (VPD). The combined effect of SM and VPD was greater than air temperature (Ta) in controlling the variations of the CP content, ADF content and nutritional quality. Compared to Ta, VPD explained more of the variation in NDF and Ash content. All of these findings suggest that warming effects on nutritional quality may vary with site and year, and water availability may have a stronger effect on the nutritional quality than temperature in the alpine meadow of the Northern Tibet.

In this work, laser cladding has been employed for the preparation of nickel-based self-lubricating coating NiCrAlY/Ag2O/Ta2O5 on Inconel 625 alloy substrate. In order to study the evolution of Ag2O and Ta2O5 in the coating and its effect on the microstructure, three coatings of NiCrAlY/Ag2O, NiCrAlY/Ta2O5 and NiCrAlY were prepared for comparison. The composition and microstructure of the powders and the corresponding composite coatings were studied by SEM-EDS and XRD. The average hardness of Coating (A, B, C, D) and substrate is 369.5 HV, 300.7 HV, 306.5 HV, 332.1 HV, and 246.8 HV, respectively. The friction and wear properties of the self-lubricating coating were studied by MFT-5000 multifunctional friction and wear tester at RT (room temperature) ~750 °C. In order to compare with the self-lubricating coating, the same friction and wear test was done on the substrate under the same condition. It can be seen that the friction coefficient of the self-lubricating coating from RT to 750 °C is 0.64, 0.23, 0.62 and 1.5 times lower than that of the substrate, and its wear rate is 2.03, 2.11, 2.82 and 1.04 times lower than that of the substrate, respectively. SEM-EDS and XRD were used to analyze the morphology and composition of the worn surface. It can be seen from the results that Ag is the main lubrication phase at room temperature, and NiO and Ag work together to lubricate at 350 °C. When the temperature reaches 550 °C, Ag loses its effective lubrication, while the wear-resistant glaze layer composed of NiO and CrO2 provides the main lubrication. At 750 °C, AgTaO3 and Ag2Ta4O11 formed by in-situ reaction will act as a synergistic lubrication with the wear resistant glaze layer composed of oxide. The synergistic lubrication of Ag, NiO, CrO2, AgTaO3 and Ag2Ta4O11 enables self-lubrication of the composite coating in a wide temperature range.

In order to make deep impression to the trainee on sounder's operation in navigation simulator education, a kind of sounder simulator was designed. It consists of signal generator and display simulator. Water depth information was generated according to GPS and Electronic Navigation Chart (ENC). Then the data was sent to display simulator through either network or serial port in the format of NMEA0183. The display simulator showed the information about water depth graphically based on OpenGL according to user's setting. Finally, the system was implemented on the cross development platform Qt. The experimental results showed that the system worked very well on both Linux/Windows platform.

A shipboard simulator based on CPLD was designed to overcome the shortcomings of existing ship bridge simulation equipment, which includes weak reality, lagging data transmission interface and low data transmission efficiency. After the completion of the analysis of ship bridge equipment, drive circuit was completed, the I/O interface resources were taken to achieve centralized control of the device; USB bridge chip was used to achieve the analog device and the host computer between the high-speed data channel so as to improve the efficiency of data transmission; PC software and firmware were respectively programmed in the VHDL language based on Quartus platform and based on the C language with VS2010 platform.

In order to overcome the problem of low integration of operating equipment, weak reality and backwardness of the data transmission interface in existing integrated bridge system simulator, a design scheme of bridge simulator based on ARM was proposed, it took microprocessor LPC1768 as core control unit, using its rich I/O resources to control equipment centrally with peripheral drive circuit. USB20D as a bridge chip was selected to achieve the data channel between host computer and microprocessor for high-speed data exchange; C language based KEIL MDK and VS2010 development platform was used to complete the firmware and application software design. The final completed bridge simulator has been already used in the Ningbo Maritime Bureau.

No studies have examined the effect of experimental warming on the microbial biomass and community composition of soil in agricultural ecosystem on the Qinghai-Tibet Plateau. Thus it is unclear whether the influences of experimental warming on microbial communities in soil are related to warming magnitude in croplands on this Plateau. This study performed warming experiment (control, low- and high-level) in a highland barley system of the Lhasa River in May 2014 to examine the correlation between the response of microbial communities in soil to warming and warming magnitude. Topsoil samples (0–10 and 10–20 cm) were collected on September 14, 2014. Experimental warming at both low and high levels significantly increased soil temperature by 1.02 °C and 1.59 °C, respectively at the depth of 15 cm. Phospho lipid fatty acid (PLFA) method was used to determine the microbial community in soil. The low-level experimental warming did not significantly affect the soil's total PLFA, fungi, bacteria, arbuscular mycorrhizal fungi (AMF), actinomycetes, gram-positive bacteria (G+), gram-negative bacteria (G–), protozoa, the ratio of fungi to bacteria (F/B ratio), and ratio of G+ to G– (G+/G– ratio) at the 0–10 and 10–20 cm depth. The low-level experimental warming also did not significantly alter the composition of microbial community in soil at the 0–10 and 10–20 cm depth. The high-level experimental warming significantly increased total PLFA by 74.4%, fungi by 78.0%, bacteria by 74.0%, AMF by 66.9%, actinomycetes by 81.4%, G+ by 67.0% and G– by 74.4% at the 0–10 cm depth rather than at 10–20 cm depth. The high-level experimental warming significantly altered microbial community composition in soil at the 0–10 cm depth rather than at 10-20 cm depth. Our findings suggest that the response of microbial communities in soil to warming varied with warming magnitudes in the highland barley system of the Lhasa River.

Soil microbes play important roles in terrestrial ecosystem carbon and nitrogen cycling. Climatic warming and elevated CO2 are two aspects of climatic change. In this study, we used a meta-analysis approach to synthesise observations related to the effects of warming and elevated CO2 on soil microbial biomass and community structure. Ecosystem types were mainly grouped into forests and grasslands. Warming methods included open top chambers and infrared radiators. Experimental settings included all-day warming, daytime warming and nighttime warming. Warming increased soil actinomycetes and saprotrophic fungi, while elevated CO2 decreased soil gram-positive bacteria (G+). Mean annual temperature and mean annual precipitation were negatively correlated with warming effects on gram-negative bacteria (G–) and total phospholipid fatty acid (PLFA), respectively. Elevation was positively correlated with the warming effect on total PLFA, bacteria, G+ and G–. Grassland exhibited a positive response of total PLFA and actinomycetes to warming, while forest exhibited a positive response in the ratio of soil fungi to bacteria (F/B ratio) to warming. The open top chamber method increased G–, while the infrared radiator method decreased the F/B ratio. Daytime warming rather than all-day warming increased G–. Our findings indicated that the effects of warming on soil microbes differed with ecosystem types, warming methods, warming times, elevation and local climate conditions.

The work efficiency of urban rail transit mostly depends on the train schedule strategy, as it could influence the balance of energy saving and passenger flow pressure to station site. In this paper, a new approach to train dispatching and schedule is introduced to optimize metro operation. Each station site adds up the amount of coming and exiting passengers as history data, and then, passenger flow prediction is carried out through Kalman filter. After data analyzing, the center server adjusts the train timetable dynamically using the exponent function.

High level liquid waste (HLLW) produced from the reprocessing of the spent nuclear fuel still contains moderate amounts of uranium, transuranium (TRU) actinides, (90)Sr, (137)Cs, etc., and thus constitutes a permanent hazard to the environment. The partitioning and transmutation (P&T) strategy has increasingly attracted interest for the safe treatment and disposal of HLLW, in which the partitioning of HLLW is one of the critical technical issues. An improved total partitioning process, including a TRPO (tri-alkylphosphine oxide) process for the removal of actinides, a CESE (crown ether strontium extraction) process for the removal of Sr, and a CECE (calixcrown ether cesium extraction) process for the removal of Cs, has been developed to treat Chinese HLLW. A 160-hour hot test of the improved total partitioning process was carried out using 72-stage 10-mm-dia annular centrifugal contactors (ACCs) and genuine HLLW. The hot test results showed that the average DFs of total α activity, Sr and Cs were 3.57 × 10(3), 2.25 × 10(4) and 1.68 × 10(4) after the hot test reached equilibrium, respectively. During the hot test, 72-stage 10-mm-dia ACCs worked stable, continuously with no stage failing or interruption of the operation.