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Microwave dielectric ceramics composed of Na1+xSrB5O9+0.5x (0 ≤ x ≤ 0.125) were synthesized via a traditional solid-state reaction approach. The effects of non-stoichiometric Na on the crystal structures, phase compositions, chemical bond characteristics, and microwave dielectric properties of the Na1+xSrB5O9+0.5x ceramics were systematically studied. All Na1+xSrB5O9+0.5x ceramics sintered at optimum temperatures consisted of a NaSrB5O9 solid-solution phase and a SrB2O4 phase. Appropriate excess Na could suppress the generation of the SrB2O4 phase, and the lowest content of the SrB2O4 phase was achieved at x = 0.075. The εr values of the Na1+xSrB5O9+0.5x ceramics were primarily affected by the relative density and molecular polarization. The Q × f values showed a positive correlation with the lattice energy. The τf value was correlated to the SrB2O4 phase content, bond valence, and bond energy. Typically, the Na1.075SrB5O9.0375 ceramic sintered at 825 °C possessed good microwave dielectric properties of εr = 5.61, Q × f = 31, 937 GHz, and τf = −3.09 ppm/°C, which are suitable for high-frequency, low-temperature co-fired ceramics (LTCCs) substrate applications.

The new numerical model for studying the dynamic evolution of soil–rock mixture landslides is presented in this article. The numerical model based on the generalized interpolation material point method analyzes a simplified slope. The gravity is linearly loaded, and the linear elastic model is used to update the stress to obtain the initial state of the slope. A small soil cohesion is set to trigger the slope sliding until the equilibrium state is reached again. During this period, the elastic–plastic material model based on the Drucker–Prager criterion is adopted for soil and stones. The differences in dynamic evolution between the homogeneous soil slope and soil–rock mixture slope are studied. Under the same stone content, the influence of the size and shape of stone on the dynamic evolution of slope is studied.

Determining the timing of E-W extension across the NS-trending rifts in southern Tibet is key to test the mechanical models of the latest evolution in the collision between India and Asia. We focus on the southern half of the largest of the seven main rifts, the Yadong-Gulu rift (YGR), which, despite being the focus of numerous studies thanks to its easy access, still lacks direct time constraints. Using illite K-Ar ages of fault gouge from the active Yadong normal fault of the YGR, we directly constrain its onset timing at 9 ± 1 Ma. (U-Th)/He dating of the footwall leucogranite reveals a rapid exhumation of the southern YGR since ∼9 Ma, attesting to its onset activity. Such timing is similar to that estimated for the northern half of the YGR at 8 ± 1 Ma, suggesting that the entire YGR formed at approximately the same time. Our synthesis of published initiation ages of the other main rifts in southern Tibet shows that they mostly fall between ∼23 and 8 Ma, suggesting a clear spatial and temporal pattern of old initiation ages to the west and young to the east. In this case, the formation of rifts in southern Tibet is unlikely caused by slab tearing of the underthruting Indian plate or orogenic collapse. Our study supports that E-W extension in Tibetan Plateau is triggered by a combination of eastward propagation of the Karakorum-Jiali fault zone and divergent thrusting along the curved Himalayan arc.

ABSTRACT Deciphering the relationships between microbes and their host plants is critical for a better understanding of microbial diversity maintenance and community stability. Here, we investigated fungal diversity and community assembly in the phyllosphere and rhizosphere of 13 tree species in a subtropical common-garden experiment. The results showed that fungal community structures significantly differed across compartments (leaf, root, and soil) and different tree species. Higher α-diversity was observed in the phyllosphere than in the roots and rhizospheric soil. Fungal community composition (β-diversity) was significantly affected by both compartment and species identity. The fungal community compositions were significantly correlated with soil pH in the roots and the soils as well as with soil nitrate and leaf total phosphorus in the leaves. We found that fungal community assemblies were mainly driven by deterministic processes, regardless of compartments. Moreover, host preference analyses indicated that stronger plant/fungus preferences occurred in leaves than in roots and soils. Our results highlight the differences in tree mycobiome between aboveground and belowground compartments and have important implications for the promotion of biodiversity conservation and management sustainability for the subtropical forest. IMPORTANCE Subtropical mountain forests are widely distributed in Southern China and are characterized by high biodiversity. The interactions between plants and fungi play pivotal roles in biodiversity maintenance and community stability. Nevertheless, knowledge of fungal diversity and of the community assembly patterns of woody plants is scarce. Here, we investigated fungal diversity and community assembly in the phyllosphere and rhizosphere of 13 tree species in a common-garden experiment. We found that both compartment and plant identity influenced fungal diversity, community, and guild compositions, while deterministic processes mainly governed the fungal community assembly, especially in the rhizospheric fungal communities. Our results demonstrate that tree leaves represent stronger host/fungi preferences than do roots and soils. Together, our findings enhance the understanding of the roles of compartment and plant identity in structuring fungal communities as well as promote fungal diversity maintenance in subtropical mountain forest ecosystems.

Double-O-tube shield tunneling technology has gained extensive attention due to saving space and the high cost-effectiveness of the underground construction method. Estimating and predicting DOT shield tunneling-induced soil displacements is essential to prevent damage to nearby aboveground and underground structures in densely populated urban areas. This study develops a device for modeling DOT shield tunneling based on transparent soil technology and image processing technique and investigates soil displacement during the construction process of the DOT shield tunnel, which is considered in the uniform convergence mode (UCM) of soil loss. Meanwhile, the soil displacement under the non-uniform convergence mode (NCM) is analyzed contrastively using a two-dimension particle flow code (PFC2D). The results show that horizontal displacements increase gradually when the shield tail passes the monitoring face, while settlements increase rapidly. The maximum horizontal displacement of the surface and the maximum surface settlement under NCM are slightly larger than those under UCM. A trapezoid-shaped failure pattern of soil is experienced at three tunnel depths. The maximum soil displacement under NCM is 1.93, 2.10, and 2.05 times, respectively, as much as that under UCM, corresponding to H/D (the ratio of the tunnel depth to the tunnel diameter) = 1.0, 1.5, and 2.0. The soil arch effect above DOT tunnels arises as the DOT tunnel depth increases. Moreover, the experimental and numerical results are adopted to assess the validity of the proposed model, which indicates that the proposed model is close to the test results of the disturbance zone on DOT tunnels.

Cenozoic collision between the Indian and Asian continents is generally considered as the main driver forming the high Tibetan Plateau (TP). However, it remains hotly debated when and how the relatively flat and highly elevated TP was formed. Here, we present combined analyses of the apatite fission track (AFT) and apatite (U-Th)/He (AHe) of 18 granite samples along three steep topographic transects in the central part of the Qiangtang Terrane (QT), TP. The results indicate that the AFT ages of all samples are mostly between 130 Ma and 80 Ma, while the AHe ages range from 80 Ma to 40 Ma. Further thermal history modeling indicates that no significant cooling occurred after 40 Ma for most samples, except those lying close to the Reganpei Co extensional fault in the QT. The results are generally consistent with other low-temperature thermochronological data, as well as structural and sedimentologic data from the QT, suggesting that low relief and the relatively flat topography of the QT were almost completely formed before ∼40 Ma. As both megafossils and pollen had undergone a sharp change from subtropical- to psychro-species, indicating a relatively low elevation (∼2 km) at ∼40 Ma and >2 km uplift during the Oligocene. We use simple one-dimensional isostatic modeling to assess the contribution of convective removal of the lithospheric mantle to the present elevation of the QT. The results suggest that a combined effect of isostatic rebound (≥2 km) and thermal expansion related to asthenosphere upwelling and subsequent crustal base heating (∼0.4 km) led to the final uplift of the QT. Therefore, the QT experienced multiple-stage uplift processes which were controlled by crustal thickening before ∼40 Ma and lithospheric mantle delamination during the Oligocene, respectively.

Welding is one of the important connection methods for zirconium alloy, and the shear failure under the dynamic load is a typical failure mode of the weld. Aiming at clarifying the shear failure of zirconium alloy welds, three kinds of double-notched shear weld specimens with welding sizes of 2, 4, and 6 mm were designed, respectively; the shear performance of specimens under quasi-static and dynamic loading was tested by tensile testing machine and split Hopkinson pressure bar (SHPB). The stress–strain curves and shear strength were determined for the weld under quasi-static and dynamic loading. It was demonstrated that 1) an obvious strain rate strengthening effect was observed for the shear strength performance of zirconium alloy weld; 2) the shear performance of zirconium alloy weld was not sensitive to its length, but the tolerance to micro defects in the weld was improved with the increase of the weld length, which gave rise to a small increment of shear strength; 3) the failure mode of zirconium alloy welds under quasi-static loading was the typical lamellar tearing failure, and the angle between the fracture and base metal was about 17°; however, the shear failure mode showed obvious brittle characteristics under dynamic loading and the angle between fracture and base metal was almost parallel to the loading direction.

Abstract Background Frosted branch angiitis (FBA) is an uncommon ocular sign with multiple causes. With the recent outbreak of coronavirus disease 2019 (COVID-19), many cases of ocular manifestation in association with this disease have been reported. However, as yet we have no complete understanding of this condition. We report here the first case of FBA in a human immunodeficiency virus-infected patient with coexisting cytomegalovirus (CMV) and COVID-19 infection. Case presentation A 33-year-old Malay man with underlying acquired immunodeficiency syndrome receiving highly active antiretroviral therapy was referred to the Opthalmology Department with complaints of blurry vision for the past 2 months. He had tested positive for and been diagnosed with COVID-19 1 month previously. Clinical examination of the fundus revealed extensive perivascular sheathing of both the artery and vein suggestive of FBA in the right eye. Laboratory testing of nasal swabs for COVID-19 polymerase chain reaction (PCR) and serum CMV antibody were positive. The patient was then admitted to the COVID-19 ward and treated with intravenous ganciclovir. Conclusion Clinicians should be aware of and take the necessary standard precautions for possible coexistence of COVID-19 in an immunocompromised patient presenting with blurred vision, eye redness, dry eye and foreign body sensation despite the absence of clinical features suggestive of COVID-19. Whether FBA is one of the ocular signs of co-infection of COVID-19 and CMV remains unknown. Further studies are needed to provide more information on ocular signs presented in patients with concurrent COVID-19 and CMV infections.

Brain tissues that are severely damaged by traumatic brain injury (TBI) is hardly regenerated, which leads to a cavity or a repair with glial scarring. Stem-cell therapy is one viable option to treat TBI-caused brain tissue damage, whose use is, whereas, limited by the low survival rate and differentiation efficiency of stem cells. To approach this problem, we developed an injectable hydrogel using imidazole groups-modified gelatin methacrylate (GelMA-imid). In addition, polydopamine (PDA) nanoparticles were used as carrier for stromal-cell derived factor-1 (SDF-1α). GelMA-imid hydrogel loaded with PDA@SDF-1α nanoparticles and human amniotic mesenchymal stromal cells (hAMSCs) were injected into the damaged area in an in-vivo cryogenic injury model in rats. The hydrogel had low module and its average pore size was 204.61 ± 41.41 nm, which were suitable for the migration, proliferation and differentiation of stem cells. In-vitro cell scratch and differentiation assays showed that the imidazole groups and SDF-1α could promote the migration of hAMSCs to injury site and their differentiation into nerve cells. The highest amount of nissl body was detected in the group of GelMA-imid/SDF-1α/hAMSCs hydrogel in the in-vivo model. Additionally, histological analysis showed that GelMA-imid/SDF-1α/hAMSCs hydrogel could facilitate the regeneration of regenerate endogenous nerve cells. In summary, the GelMA-imid/SDF-1α/hAMSCs hydrogel promoted homing and differentiation of hAMSCs into nerve cells, and showed great application potential for the physiological recovery of TBI.

Abstract Temozolomide (TMZ)-resistance hampers the therapeutic efficacy of this drug for glioblastoma (GBM) treatment in clinic, and emerging evidences suggested that exosomes from GBM-derived stem cells (GSCs) contributed to this process, but the detailed mechanisms are still largely unknown. In the present study, we reported that GSCs derived programmed death-ligand 1 (PD-L1) containing exosomes activated AMPK/ULK1 pathway mediated protective autophagy enhanced TMZ-resistance in GBM in vitro and in vivo. Specifically, we noticed that continuous low-dose TMZ stimulation promoted GSCs generation and PD-L1 containing exosomes (PD-L1-ex) secretion in GBM cells, and that PD-L1-ex inhibited cell apoptosis and promoted cell autophagy to increased TMZ-resistance in GBM cells, which were reversed by co-treating cells with the autophagy inhibitor 3-methyladenine (3-MA). Consistently, upregulation of PD-L1 also increased TMZ-resistance in TS-GBM cells, and silencing of PD-L1 sensitized TR-GBM cells to TMZ. In addition, PD-L1-ex activated AMPK/ULK1 pathway to induce autophagy in TMZ treated GBM cells, and the inhibitors for AMPK (compound C) and ULK1 (SBI-0206965) promoted cell apoptosis in GBM cells co-treated with PD-L1-ex and high-dose TMZ. Finally, we evidenced that PD-L1-ex promoted tumor growth and Ki67 protein expressions to increase TMZ-resistance in GBM in vivo. Collectively, we concluded that GSCs-derived PD-L1-ex activated AMPK1/ULK1 signaling cascade mediated autophagy to increase TMZ-resistance in GBM, and this study provided potential strategies to improve the therapeutic efficacy of TMZ in GBM.

Natural rubber is an important and strategic raw material, used in tires, gloves, and insulating products, that is mainly obtained by cutting the bark of rubber trees. However, the complex contour curve of the rubber tree trunk is hard to fit using a tapping machine. Thus, a trunk contour curve collection would be useful for the development of tapping machines. In this study, an acquisition system based on laser-ranging technology was proposed to collect the point cloud data of rubber tree trunks, and a B-spline fitting program was compiled in Matrix Laboratory (MATLAB) to extract the trunks’ contour curves. The acquisition system is composed of power, a controller, a driver, a laser range finder, and data transmission modules. An automatic extraction experiment on the contour curves of rubber tree trunks was carried out to verify the feasibility and accuracy of using the acquisition system. The results showed that the degree of rubber tree trunk characteristic recognition reached 94.67%, which means that the successful extraction of the rubber tree trunk contour curves and the B-spline fitting program are suitable for the extraction of irregular curves of rubber tree trunks. The coefficient of variation of repeated collection was 0.04%, which indicates that changes in relative positions and acquisition directions have little influence on the extraction and the accuracy of the acquisition system, which are high and stable. Therefore, it was unnecessary to adjust the position of the acquisition device before the collecting process, which helped to improve the efficiency of acquisition considerably. The acquisition system proposed in this study is meaningful to the practical production and application of agroforestry and can not only improve the precision of the rubber tapping process by combining with an automatic rubber tapping machine but can also provide technical support for the prediction of rubber wood volume and the development of ring-cutting equipment for other fruit trees.

Abstract Background Cogan’s anterior internuclear ophthalmoplegia (INO) is characterized by INO with inability to converge and commonly thought to be due to rostral midbrain lesion. A lesion outside midbrain that causes unilateral Cogan’s anterior INO combined with upgaze palsy and ataxia are rarely described. Case presentation A 67-year old male presented with left Cogan’s anterior internuclear ophthalmoplegia (INO), left appendicular ataxia and bilateral upgaze palsy. A Magnetic Resonance Imaging (MRI) and Magnetic Resonance Angiography (MRA) brain showed a left dorsal tegmental infarct at the level of pontomesencephalic junction. Conclusions This case highlights the clinical importance of Cogan’s anterior INO in combination with upgaze palsy and ataxia, and report possible site of lesion in patients with such constellation. Clinicians should consider looking for cerebellar signs in cases of Cogan’s anterior INO, apart from just considering localizing the lesion at the midbrain.

Coronary artery segmentation is a major step in coronary heart disease computer-aided diagnosis systems, which is used to ensure only the coronary artery region to be processed in subsequent steps. The coronary computed tomography angiography (CCTA) image has its own inherent characteristics, such as unclear boundary, complicated structure, and inconspicuous features, which make the CCTA image segmentation a difficult task. To address this problem, the fusion of geometric features of the image can enhance the feature learning ability of network, thereby improving the segmentation accuracy. Therefore, we proposed a coronary segmentation method that integrates the geometric features into Mask RCNN. Boundary extraction algorithm and fractal feature extraction algorithm are proposed to extract boundary and fractal features. Through the feature fusion method, the boundary features and fractal features are fused into the network. Experimentally, we evaluated the proposed method by using coronary artery dataset. The average accuracy (PA) and Dice coefficient of the proposed method reached 83% and (84.0±10.1)%, respectively. The test results demonstrate that the proposed method provides greater accuracy and robustness.

This study aims to explore new educational strategies suitable for the mental health education of college students. Big data and artificial intelligence (AI) are combined to evaluate the mental health education of college students in sports majors. First, the research status on the mental health education of college students is introduced. The internet of things (IoT) on mental health education, a structure based on big data and convolutional neural network (CNN), is constructed. Next, the survey design and questionnaire survey are carried out. Finally, the questionnaire data are analyzed and compared with the mental health status under traditional education. The results show that the CNN model has good accuracy and ability to distinguish symptoms, so it can be applied to the existing psychological work in colleges. In the symptom comparison survey, under the traditional education and big data network, the number of college students with mild mental health problems is found to be 158 (84.9%) and 170 (91.4%), respectively. It indicates that the number of college students with moderate mental health problems decreases significantly. In the comparative investigation of the severity of mental problems, the number of students with normal mental health, subhealth, and serious mental health problems under the background of traditional mental health education is 125 (67.2%), 56 (30.1%), and 5 (2.7%), respectively. The mental health status of college students under the influence of big data networks on mental health education is better than that of traditional mental health education. There are 140 students with normal mental health, a year-on-year increase of 16.7%. In the comparative survey of specific mental disorders, students with obsessive-compulsive symptoms under traditional mental health education account for 22.0% of the total sample, having the largest proportion. In the subhealth psychological group under the big data network on mental health education, the number of hostile students decreases by 7, which is the psychological factor with the most obvious improvement. Hence, the proposed path of mental health education is feasible.

Abstract Background We aimed to distinguish the preoperative radiological indicators to predict the application of assistant techniques during intubation for patients undergoing selective cervical surgery. Methods A total of 104 patients were enrolled in this study. According to whether intubation was successfully accomplished by simple Macintosh laryngoscopy, patients were divided into Macintosh laryngoscopy group (n = 78) and Assistant technique group (n = 26). We measured patients’ radiographical data via their preoperative X-ray and MRI images, and compared the differences between two groups. Binary logistic regression model was applied to distinguish the meaningful predictors. Receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to describe the discrimination ability of indicators. The highest Youden’s index corresponded to an optimal cut-off value. Results Ten variables exhibited significant statistical differences between two groups (P

Halophytes have high species diversity and play important roles in ecosystems. However, endophytic fungi of halophytes in desert ecosystems have been less investigated. In this study, we examined endophytic fungi associated with the stem and root of ten halophytic species colonizing the Gurbantonggut desert. A total of 36 endophytic fungal taxa were obtained, dominated by Alternaria eichhorniae, Monosporascus ibericus, and Pezizomycotina sp.1. The colonization rate and species richness of endophytic fungi varied in the ten plant species, with higher rates in roots than in stems. The endophytic fungal community composition was significantly affected by plant identity and tissue type. Some endophytic fungi showed significant host and tissue preferences. This finding suggests that host identity and tissue type structure endophytic fungal community in a desert ecosystem.

Biological soft tissues are intrinsically viscoelastic materials which play a significant role in affecting the activity of cells. As potential artificial alternatives, double-network (DN) gels, however, are pure elastic and mechanically time independent. The viscoelasticization of DN gels is an urgent challenge in enabling DN gels to be used for advanced development of biomaterial applications. Herein, we demonstrate a simple approach to regulate the viscoelasticity of tough double-network (DN) hydrogels by forming sulfonate–metal coordination. Owing to the dynamic nature of the coordination bonds, the resultant hydrogels possess highly viscoelastic, mechanical time-dependent, and self-recovery properties. Rheological measurements are performed to investigate the linear dynamic mechanical behavior at small strains. The tensile tests and cyclic tensile tests are also systematically performed to evaluate the rate-dependent large deformation mechanical behaviors and energy dissipation behaviors of various ion-loaded DN hydrogels. It has been revealed based on the systematic analysis that robust strong sulfonate–Zr4+ coordination interactions not only serve as dynamic crosslinks imparting viscoelastic rate-dependent mechanical performances, but also strongly affect the relative strength of the first PAMPS network, thereby increasing the yielding stress σy and the fracture stress at break σb and reducing the stretch ratio at break λb. It is envisioned that the viscoelasticization of DN gels enables versatile applications in the biomedical and engineering fields.

The Kirigami approach is an effective way to realize controllable deformation of intelligent materials via introducing cuts into bulk materials. For materials ranging from ordinary stiff materials such as glass, ceramics, and metals to soft materials, including ordinary hydrogels and elastomers, all of them are all sensitive to the presence of cuts, which usually act as defects to deteriorate mechanical properties. Herein, we study the influence of the cuts on the mechanical properties by introducing “dispersed macro-scale cuts” into a model tough double network (DN) hydrogel (named D-cut gel), which consists of a rigid and brittle first network and a ductile stretchable second network. For comparison, DN gels with “continuous cuts” having the same number of interconnected cuts (named C-cut gel) were chosen. The fracture tests of D-cut gel and C-cut gel with different cut patterns were performed. The fracture observation revealed that crack blunting occurred at each cut tip, and a large wrinkle-like zone was formed where the wrinkles were parallel to the propagation direction of the cut. By utilizing homemade circular polarizing optical systems, we found that introducing dispersed cuts increases the rupture force by homogenizing the stress around the crack tip surrounding every cut, which reduces stress concentration in one certain cut. We believe this work reveals the fracture mechanism of tough soft materials with a kirigami cut structure, which should guide the design of advanced soft and tough materials along this line.

Dwarf galaxies are found to have lost most of their metals via feedback processes; however, there still lacks consistent assessment on the retention rate of metals in their circumgalactic medium (CGM). Here we investigate the metal content in the CGM of 45 isolated dwarf galaxies with M _* = 10 ^6.5–9.5 M _⊙ ( M _200m = 10 ^10.0–11.5 M _⊙ ) using the Hubble Space Telescope/Cosmic Origins Spectrograph. While H i (Ly α ) is ubiquitously detected (89%) within the CGM, we find low detection rates (≈5%–22%) in C ii , C iv , Si ii , Si iii , and Si iv , largely consistent with literature values. Assuming these ions form in the cool ( T ≈ 10 ^4 K) CGM with photoionization equilibrium, the observed H i and metal column density profiles can be best explained by an empirical model with low gas density and high volume filling factor. For a typical galaxy with M _200m = 10 ^10.9 M _⊙ (median of the sample), our model predicts a cool gas mass of M _CGM,cool ∼ 10 ^8.4 M _⊙ , corresponding to ∼2% of the galaxy’s baryonic budget. Assuming a metallicity of 0.3 Z _⊙ , we estimate that the dwarf galaxy’s cool CGM likely harbors ∼10% of the metals ever produced, with the rest either in more ionized states in the CGM or transported to the intergalactic medium. We further examine the EAGLE simulation and show that H i and low ions may arise from a dense cool medium, while C iv arises from a diffuse warmer medium. Our work provides the community with a uniform data set on dwarf galaxies’ CGM that combines our recent observations, additional archival data and literature compilation, which can be used to test various theoretical models of dwarf galaxies.

Abstract Recommender systems (RS) have been applied in the area of educations to recommend formal and informal learning materials, after-school programs or online courses. In the traditional RS, the receiver of the recommendations is the only stakeholder, but other stakeholders may be involved in the environment. Take educations for example, not only the preference of the student, but also the perspective of other stakeholders (e.g., instructors, parents, publishers, etc) may be important in the process of recommendations. Multi-stakeholder recommender systems (MSRS) were recently proposed to balance the needs of multiple stakeholders in the recommender systems. We use course project recommendations as a case study, and the perspectives of both students and instructors will be considered in our work. However, students and instructors may have different perceptions on the technical difficulty of the projects. In this paper, we particularly focus on the solution of preference corrections which can be used to capture different perceptions of students and instructors in the multi-stakeholder educational recommendations.

The Cenozoic collision between India and Asia promoted the widespread uplift of the Tibetan Plateau, with significant deformation documented in the Pamir Plateau and West Kunlun Mountains. Low-temperature thermochronology and basin provenance analysis have revealed three episodes of rapid deformation and uplift in the Pamir–West Kunlun Mountains during the Cenozoic. However, there is very little low-temperature thermochronology age–elevation relationship (AER) data on fast exhumation events in this area—especially in the West Kunlun Mountains— leading to uncertainty surrounding how these events propagated within and around the mountain range. In this study, we produced an elevation profile across granite located south of Kudi, Xijiang Province, China, to reveal its exhumation history. Apatite fission track AER data show that a rapid exhumation event occurred at ∼26 Ma in the southern West Kunlun Mountains. When combined with published data, we interpret that the initial uplift events related to the India–Asia collision began in the central Pamir, southern West Kunlun, and northern West Kunlun regions during the Late Eocene, Oligocene, and Middle Miocene periods, respectively. Therefore, the Cenozoic northward growth process occurred from south to north around West Kunlun.

Soil fungi play a critical role in the carbon and nutrient cycling of forest ecosystems. Identifying the composition of soil fungi in response to the broadleaf restoration of Pinus massoniana plantation is essential for exploring the mechanistic linkages between tree species and ecological processes, but remains unexplored. We compared the shifts in soil fungal diversity and guilds by high–throughput sequencing between two P. massoniana plantations at different stand ages, two modes of restoration with broadleaf trees, and a secondary forest in subtropical China. We found that soil fungal taxonomic and functional compositions significantly differed among forests. The highest Chao 1, Shannon, and phylogenetic diversity indices were consistently observed in the two P. massoniana monocultures, followed by the two modes of broadleaf mixing, and the secondary forests. Fungal communities transitioned from Ascomycota-dominated at P. massoniana plantations to Basidiomycota-dominated at other forests in the topsoil. Furthermore, saprotrophs and symbiotrophs were favoured in plantations and secondary forests, respectively. Soil pH exerted the most significant effect on the relative abundance of Ascomycota and Rozellomycota, as well as the saprotrophs. Moreover, the dominant phyla of Ascomycota, Mucoromycota, and Rozellomycota were negatively related to soil microbial biomass nitrogen, ammonium nitrogen, and total nitrogen contents; however, Mortierellomycota benefited from the elevated soil ammonium nitrogen content. On the other hand, soil nitrate nitrogen and available phosphorus contents strongly and negatively influenced the ectomycorrhizal fungi, while the other fungal guilds were mainly affected by soil pH. Our findings guide an evaluation of the consequences of forest restoration and contribute to an improved understanding of the mechanisms behind soil biogeochemical cycling in subtropical forest ecosystems.

The Pamir Plateau region of the Northwestern Tibetan Plateau forms a prominent tectonic salient, separating the Tajik and Tarim basins. However, the topographic evolution of the Pamir Plateau remains elusive, despite the key role of this region played in the retreat of the Paratethys Ocean and in aridification across Central Asia. Therefore, the SW Tarim and Tajik basins are prime locations to decipher the geological history of the Pamir Plateau. Here, we present detrital zircon U/Pb and apatite fission-track (DAFT) ages from the Keliyang section of the SW Tarim Basin. DAFT ages show that sediments had three components during the Late Cretaceous and two components since the Oligocene. Detrital zircon U/Pb ages mainly cluster between 400 and 500 Ma during the Late Cretaceous, and coincide with ages of the Songpan-Ganzi and the West Kunlun Mountains. In contrast, detrital zircon U/Pb ages in the Eocene sediments are centered at around 200–300 Ma and 40–70 Ma, with a peak at ∼45 Ma, consistent with data from the Central Pamir and the West Kunlun Mountains. The ∼45 Ma peak in detrital zircon U/Pb ages since the Eocene indicates a new sedimentary source from the Central Pamir. Non-metric multi-dimensional scaling (MDS) analyses also show that the sedimentary source was closer to the Central Pamir after the Eocene, when compared to the Late Cretaceous. The result shows a clear Eocene provenance change in the Keliyang area. Moreover, this Eocene provenance shift has been detected in previous studies, in both the Tajik and Tarim basins, suggesting that the entire Central Pamir region likely experienced quasi-simultaneous abrupt uplift and paleo-geomorphological changes during the Eocene.

BackgroundZimberelimab (GLS-010) is a novel fully human monoclonal immunoglobulin G4 (IgG4) against the programmed cell death-1 (PD-1) receptor.AimTo evaluate the affinity, competitive blocking capability, T cell activation effect, cytotoxic effector functions by Fc, preliminary anti-tumor activity, and pharmacokinetics of GLS-010.MethodsThe affinity of GLS-010 to PD-1 and the ability of GLS-010 to block the PD-L1/2 to PD-1 interaction on the cell surface were measured. An allogeneic mixed lymphocyte reaction was conducted to evaluate the inhibitory effect of GLS-010 on Tregs and stimulatory effect on T cell proliferation and activation. Pharmacodynamics and pharmacokinetics were evaluated in tumor-bearing mice and cynomolgus monkeys, respectively.ResultsThe equilibrium dissociation constant (KD) for the association between GLS-010 and PD-1 was 1.75×10-10 M. GLS-010 could effectively block the binding of PD-L1/2 to PD-1. GLS-010 showed statistically significant anti-tumor effects in the MC38 model in human PD-1 knock-in mice. The RO rate on in the low-, moderate-, and high-dose groups were 64.50%-48.53% in CD3+T, 58.87%-40.12% in CD8+T, and 66.26%-49.07% in CD4+T, respectively. With the increasing dose from 2 mg/kg to 18 mg/kg, the systemic exposure level of GLS-010 (AUC0-last) and C0 increased proportionally, while the proportion of AUC0-last was higher than the proportion of the increase in the dose.ConclusionsAs a fully human anti-PD-1 monoclonal antibody, GLS-010 has a high affinity to PD-1 and shows potent anti-tumor effects in vivo and in vitro. The results support that GLS-010 could be investigated in clinical trials in tumor patients.

Traditionally, fatigue cracking in asphalt pavement means fatigue failure, which is the basis for controlling the design thickness of asphalt pavements. In fact, the fatigue failure of asphalt pavements includes three stages: fatigue cracking, crack expansion, and structural failure. Therefore, this paper aims to investigate the fatigue life of the bottom-up cracking of asphalt concrete (AC) pavements considering the different stages of fatigue failure. The dynamic modulus of AC of different grades was experimentally determined. The tensile stresses at the bottom of the AC layer were evaluated by embedding the tested dynamic modulus into a numerical simulation, which can be used to calculate the fatigue cracking life. Then, overlay tests (OTs) at different temperatures were conducted to obtain the fracture parameters A and n from the asphalt mixture. The crack propagation life was calculated via the Paris formula based on the fracture parameters A and n. The analysis results showed that an increase in AC thickness could effectively improve the fatigue crack life of the pavement structure, and the proportion of crack propagation life to fatigue crack life at different temperatures varied significantly. Therefore, when analyzing and calculating the fatigue life of pavement structures, besides the fatigue cracking life, the crack propagation life after cracking should also be considered, which is very important for accurately calculating the entire fatigue life of asphalt pavement structures. This will offer guidance for asphalt pavement thickness design.

YSZ has been widely used as a TBC material, but its phase change at high temperatures limits its development, thus the need for developing new thermal barrier materials resistant to high temperatures. Rare-earth aluminate ceramics with a garnet structure (Yb3Al5O12) have been considered as a potential thermal barrier material. The melting point of Yb3Al5O12 is 2000 °C, which has a potential high temperature application prospect. However, Yb3Al5O12 has lower thermal expansion and higher thermal conductivity than YSZ, which is a widely employed thermal barrier coating (TBC) material. To overcome these obstacles, (Y0.2Dy0.2Ho0.2Er0.2Yb0.2)3Al5O12, a high-entropy ceramic, was prepared by a solid-state reaction and pressureless sintering. The thermal conductivity of the (Y0.2Dy0.2Ho0.2Er0.2Yb0.2)3Al5O12 was 3.48 W/(m·K) at 300 K, approximately 25.48% lower than that of the Yb3Al5O12 (4.67 W/(m·K)). The thermal expansion coefficient of the (Y0.2Dy0.2Ho0.2Er0.2Yb0.2)3Al5O12 was 9.28 × 10−6 K−1 at 673-1273 K, approximately 18.52% higher than that of the Yb3Al5O12 (7.83 × 10−6 K−1, 673-1273 K). When the (Y0.2Dy0.2Ho0.2Er0.2Yb0.2)3Al5O12 was annealed at 1550 °C for 7 days, its average grain size only increased from 0.7 μm to 1.3 μm. Moreover, the (Y0.2Dy0.2Ho0.2Er0.2Yb0.2)3Al5O12 exhibited better chemical stability and a lower grain growth rate than the Yb3Al5O12. This study reveals that (Y0.2Dy0.2Ho0.2Er0.2Yb0.2)3Al5O12 is a promising candidate for the future generation of thermal barrier materials.

In the probe limit, we construct the p-wave conductor/superconductor phase transition with momentum relaxation originated from the axion fields by both numerical and analytical methods, and then study the effects of relaxation parameter (k/μ) on the superconductor model. Concretely, the increasing k/μ decreases monotonously the critical temperature and thus hinders the phase transition. The stable value of condensate (C00≡〈Jx〉1/(Δ+1)/μ|T≈0.15Tc) and the coefficient (C1) of condensate (〈Jx〉/μ1/(Δ+1)=C11−T/Tc|T≈Tc) always decrease with the larger k/μ. Near the critical point, the system suffers from a second order phase transition. Meanwhile, for fixed value of k/μ, the larger mass of vector field also suppresses the vector condensate to emerge. As for the above conclusions, the analytical results from the improved trial function agree with the numerical ones. The calculation of the ratio of energy gap to the critical temperature shows that the present superconductor indeed involves strong interaction, which increases with the increasing k/μ.

In order to improve the indexing accuracy of CNC gear shaper YKD5132X3, the transmission error of gear shaper is detected. After analyzing the data, it is concluded that the main error sources of indexing error are workpiece worktable worm gear and cutter stand worktable worm gear pair. Aiming at these two error sources, the two worm gears are processed by the refined worm wheel master machine of our research group, and the on-line detection is realized through the on-line detection device. After the worm gear is finished, when the gear shaper is assembled, the installation of the workpiece worm gear is adjusted by TE data. The method of adjusting and installing many times in the past is replaced, which saves the installation time and improves the installation precision. Finally, the gear cutting accuracy of gear shaper is improved from 7-level to 5-level.

Abstract The dramatic climate fluctuations of the late Quaternary have influenced the diversity and composition of macroorganism communities, but how they structure belowground microbial communities is less well known. Fungi constitute an important component of soil microorganism communities. They play an important role in biodiversity maintenance, community assembly, and ecosystem functioning, and differ from many macroorganisms in many traits. Here, we examined soil fungal communities in Chinese temperate, subtropical, and tropic forests using Illumina MiSeq sequencing of the fungal ITS1 region. The relative effect of late Quaternary climate change and contemporary environment (plant, soil, current climate, and geographic distance) on the soil fungal community was analyzed. The richness of the total fungal community, along with saprotrophic, ectomycorrhizal (EM), and pathogenic fungal communities, was influenced primarily by the contemporary environment (plant and/or soil) but not by late Quaternary climate change. Late Quaternary climate change acted in concert with the contemporary environment to shape total, saprotrophic, EM, and pathogenic fungal community compositions and with a stronger effect in temperate forest than in tropic–subtropical forest ecosystems. Some contemporary environmental factors influencing total, saprotrophic, EM, and pathogenic fungal communities in temperate and tropic–subtropical forests were different. We demonstrate that late Quaternary climate change can help to explain current soil fungal community composition and argue that climatic legacies can help to predict soil fungal responses to climate change.

Abstract Background Seed germination and seedling establishment are two of the most critical phases in plant development. However, the molecular mechanisms underlying the effect of phosphorus on seed germination and post-germinated growth of oilseed rape are unclear so far. Here, we report the role of BnPHT1;4 in seed germination and early seedling development of Brassica napus. Results Our results show that BnPHT1;4 is preferentially expressed in cotyledons of early developing seedlings. Overexpression of BnPHT1;4 in oilseed rape promoted seed germination and seedling growth. Expression levels of the genes related to ABA and GA biosynthesis and signaling were significantly altered in BnPHT1;4 transgenic seedlings. Consequently, active GA level was up-regulated, whereas ABA content was down-regulated in BnPHT1;4 transgenic seedlings. Furthermore, exogenous GA could promote seed germination of wild type, while exogenous ABA could partially recover the advanced-germination phenotype of BnPHT1;4 transgenic seeds. Total phosphorus content in cotyledons of the transgenic seedlings was decreased more rapidly than that in wild type when Pi was supplied or deficient, and Pi contents in shoots and roots of the BnPHT1;4 transgenic plants were higher than those in wild type under high and low Pi conditions. Conclusions Our data suggest that the high-affinity transporter BnPHT1;4 is involved in phosphorus acquisition and mobilization for facilitating seed germination and seedling growth of Brassica napus by modulating ABA and GA biosynthesis.

The high frequency isolated quasi Z-source inverter is a new type of inverter, which is suitable for photovoltaic generation system because of its high lift to voltage ratio, transient bridge direct access and electrical isolation.With the increase of its power density, the working frequency of its semiconductor switching devices is increasing. Switching devices in high-frequency states generate a large amount of electromagnetic noise, affecting the normal operation of surrounding electrical equipment and threatening the stability of the power grid. For the optimization of electromagnetic compatibility of high frequency isolation quasi Z-source inverter, using pulse width modulation (PWM) chaotic modulation technology, put forward using Chen multi-scroll chaotic system and traditional PWM are combined, using the new PWM control technology can inhibit electromagnetic interference (EMI) from the noise source, effectively reduce the high frequency isolation quasi Z-source switch frequency and its harmonics noise power, and optimize the total harmonic distortion (THD) of the output current by analyzing the chaotic modulation coefficient. Finally, the correctness of the theory is verified by Saber simulation and circuit test. This paper can provide guidelines for the electro magnetic compatibility (EMC) design of the high frequency isolated quasi Z-source inverter and provide the theoretical basis for the EMI optimization design of the power electronic system.

Z-source photovoltaic inverters feature a unique topology and a special modulation strategy that enables a traditional two-stage system function through a single-stage structure. Therefore, Z-source inverters are expected to gain an extensive application when inputs change significantly. Given the objective of achieving DC-link voltage control based on small-signal model analyses, this study proposes a sliding-mode control method with a multipower approaching law (MPAL) for the DC-link control of inverters. This novel approach can solve the slow convergence rate and serious buffeting of the traditional sliding-mode control. The proposed approach makes the system state reach the sliding surface rapidly. The inherent buffeting of the sliding-mode control is simultaneously weakened and even eliminated in a few cases. The simulation and experimental analyses prove that the proposed sliding-mode control with an MPAL features significant advantages unlike the traditional sliding-mode control and provides a certain practical value.

Layered asphalt pavement makes the interlayer contact more complicated. In order to further understand the characteristics of interlayer interface of asphalt pavement under vehicle load, this paper analyzes the change rule of interlayer interface of asphalt pavement under a vertical load condition, based on the Goodman model. According to the characteristics of asphalt pavement, the experiment temperature, gradation, amount of viscosity-level oil, type of viscosity-level oil, and vertical compressive stress are taken as parameters, and the universal testing machine (UTM) and self-modified test fixture are used to carry out the direct interlayer shear test. Experimental results show that the vertical load has a significant effect on the characteristics of the interlayer interface. With an increase in the vertical load, the maximum bonding coefficient changes greatly. Additionally, when the vertical load is constant, the temperature and spreading amount of viscosity-level oil have a strong influence on the interlayer bonding state. With an increase in temperature, the maximum bonding coefficient decreases. The adhesion coefficient increases first and then decreases with increasing spreading amount. The best spreading amounts of oil between the upper and middle layers, the middle and lower layers, and the lower layer and cement-stabilized base layer under different vertical load conditions are recommended. This study offers important guidance for designing pavement structure.

To promote the coordinated development between renewable energy and the distribution network, a capacity allocation model of battery energy storage systems (BESS) is proposed to achieve the coordinated optimization for active and reactive power flow, which can reduce the voltage deviation and improve the absorptive capacity for renewable energy. In addition, BESS with four-quadrant operation characteristics, on-load tap changer, and capacitor banks are treated as flexible devices to improve the adaptability for renewable energy fluctuations. In view of the uncertainties of renewable energy caused by the inaccuracy of historical sample data, a set of extreme scenarios with the characteristics of temporal and spatial correlation are considered to obtain a robust BESS configuration decision. The big-M approach and the second-order conic relaxation technique are utilized to convert the BESS capacity allocation model into a mixed-integer linear programming problem. Finally, the IEEE 33-node distribution system is taken as an example to verify the effectiveness of the proposed method.

Understanding the relationships between giant panda (Ailuropoda melanoleuca) and their sympatric species is an important component in their conservation. In this study we evaluate the impact of sympatric species with three ranges of body size on the distribution and habitat selection of giant panda. We surveyed giant panda and their sympatric species occurrences by camera trapping and field survey in the Wanglang Nature Reserve, Sichuan, from May 2018 to June 2019. Ten wild species and one domestic species with high photographic presences were selected and clustered by body size indicators. Generalized linear models and redundancy analysis showed that the distribution of giant panda was significantly influenced by the presence of large- and medium-sized species and domestic cattle, but less so by small-sized species. Giant panda tend to avoid cattle by choosing more inferior habitats. Differences in the impact of the ten sympatric species and cattle on the giant panda habitat selection are reflected in three variables: slope, tree density and herb coverage. Our study suggests that; i) more attention should be paid to habitat protection and restoration, particularly for those habitats identified as most suitable for giant pandas; ii) as body size of other species present is a factor which adversely influences giant panda distribution, reductions in large-sized grazing species will be necessary to support giant pandas in nature reserves, and iii) residents should consider replacing cattle with smaller-sized domestic species.

Plasmids are mostly found in bacteria as extrachromosomal genetic elements and are widely used in genetic engineering. Exploring the mechanisms of plasmid–host interaction can provide crucial information for the application of plasmids in genetic engineering. However, many studies have generally focused on the influence of plasmids on their bacterial hosts, and the effects of plasmids on bacteria-feeding animals have not been explored in detail. Here, we use a “plasmid–bacteria–Caenorhabditis elegans” model to explore the impact of plasmids on their host bacteria and bacterivorous nematodes. First, the phenotypic responses of C. elegans were observed by feeding Escherichia coli OP50 harboring different types of plasmids. We found that E. coli OP50 harboring plasmid pEX18Gm unexpectedly increases the fecundity of C. elegans. Subsequently, we found that the plasmid pEX18Gm indirectly affects C. elegans fecundity via bacterial metabolism. To explore the underlying regulatory mechanism, we performed bacterial RNA sequencing and performed in-depth analysis. We demonstrated that the plasmid pEX18Gm upregulates the transcription of methionine synthase gene metH in the bacteria, which results in an increase in methionine that supports C. elegans fecundity. Additionally, we found that a pEX18Gm-induced increase in C. elegans can occur in different bacterial species. Our findings highlight the plasmid–bacteria–C. elegans model to reveal the mechanism of plasmids’ effects on their host and provide a new pattern for systematically studying the interaction between plasmids and multi-species.

Research suggests that peer injunctive norms (i.e., perceived attitudes) have an indirect effect on youth’s behavior. Few studies have explored the underlying mechanism of the relationship between the perceived attitude of gender-specific close friends and hookup behavior. Following the social norm approach and the social learning theory, a person’s own hookup attitude and their emotional reaction after a hookup would influence this relationship as mediators. We therefore examined the association between perceived hookup attitudes of students’ same-sex/opposite-sex close friends and the number of hookup partners via mediated variables (i.e., own hookup attitude and affect following a recent hookup) in Chinese college students (N = 314) who completed self-report measures at 6-month intervals. The results of a path analysis showed that students’ own attitudes toward hookups and negative affect following a hookup significantly mediated the association between perceived hookup attitudes of same-sex close friends and the number of hookup partners over 6 months. These findings indicate that same-sex close friends’ injunctive norms were more strongly associated with future hookup behavior, as compared to opposite-sex friends’ injunctive norms. To better understand the relationship between peer norms and hookup behavior, both students’ hookup attitudes and negative emotional responses should be considered.

Grazing as one of the most important disturbances affects the abundance, diversity and community composition of arbuscular mycorrhizal (AM) fungi in ecosystems, but the AM fungi in response to grazing in wetland ecosystems remain poorly documented. Here, we examined AM fungi in roots and soil in grazing and non-grazing plots in Zoige wetland on the Qinghai-Tibet plateau. Grazing significantly increased AM fungal spore density and glomalin-related soil proteins, but had no significant effect on the extra radical hyphal density of AM fungi. While AM fungal richness and community composition differed between roots and soil, grazing was found to influence only the community composition in soil. This study shows that moderate grazing can increase the biomass of AM fungi and soil carbon sequestration, and maintain the AM fungal diversity in the wetland ecosystem. This finding may enhance our understanding of the AM fungi in response to grazing in the wetland on the Qinghai-Tibet plateau.

This dataset contains demographic information of 355 respondents and a validated 32-items Stages of Concerns Questionnaire (SoCQ). The SoCQ questionnaire was developed based on the Concerns-Based Adoption Model (CBAM) which measures seven stages of concerns as the variables. They are unconcerned, informational, personal, management, consequence, collaboration and refocusing. The data was firstly tested with normality, followed by validity checking using confirmatory factor analysis (CFA). It is useful for policy makers and stakeholders to have a thorough understanding about teachers’ concerns on the use of the e-learning platform and thus, design suitable interventions to smoothen the adoption process of using the technology. This set of data could be used in a multi-racial developing country for more complex analyses. Keywords: Concerns based adoption model (CBAM), Reliability and validity, Covariance-based structural equation modelling (CBSEM), Confirmatory factor analysis (CFA)

The interaction between aboveground and belowground biotic communities drives community assembly of plants and soil microbiota. As an important component of belowground microorganisms, root-associated fungi play pivotal roles in biodiversity maintenance and community assembly of host plants. The Betulaceae plants form ectomycorrhizae with soil fungi and widely distribute in various ecosystems. However, the community assembly of endophytic fungi in ectomycorrhizae is less investigated at a large spatial scale. Here, we examined the endophytic fungal communities in ectomycorrhizae of 22 species in four genera belonging to Betulaceae in Chinese forest ecosystems, using Illumina Miseq sequencing of internal transcribed spacer 2 amplicons. The relative contribution of host phylogeny, climate and soil (environmental filtering) and geographic distance (dispersal limitation) on endophytic fungal community was disentangled. In total, 2,106 endophytic fungal operational taxonomic units (OTUs) were obtained at a 97% sequence similarity level, dominated by Leotiomycetes, Agaricomycetes, Eurotiomycetes, and Sordariomycetes. The endophytic fungal OTU richness was significantly related with host phylogeny, geographic distance, soil and climate. The endophytic fungal community composition was significantly affected by host phylogeny (19.5% of variation explained in fungal community), geographic distance (11.2%), soil (6.1%), and climate (1.4%). This finding suggests that environmental filtering by plant and abiotic variables coupled with dispersal limitation linked to geographic distance determines endophytic fungal community assembly in ectomycorrhizae of Betulaceae plants, with host phylogeny being a stronger determinant than other predictor variables at the regional scale.