Multiple parallel deinonychosaurian trackways from a diverse dinosaur track assemblage of the Lower Cretaceous Dasheng Group of Shandong Province, China

Many newly-discovered dinosaur tracksites have recently been reported from the Lower Cretaceous Dasheng Group of Shandong Province. These are proving valuable as tools for characterizing the fauna in deposits almost devoid of body fossils. Here we report on a new Cretaceous site, the 14th documented in recent years, with multiple track-bearing levels, that adds ∼300 tracks to a growing database. At least two morphotypes tentatively labelled as cf. Menglongpus isp., representing a deinonychosaur, and cf. Tatarornipes isp., representing an avian theropod, add to the list of at least seven named ichnogenera attributed to avian and non-avian theropods reported from the Dasheng Group in Shandong Province. Combined with two sauropodomorph and two ornithopod ichnogenera, and unnamed turtle tracks, the genus-level ichnodiversity (∼14) is one of the highest reported for any Cretaceous unit either regionally in China or globally. The tracks identified as cf. Menglongpus isp. occur in four parallel trackways indicating a group of small didactyl bipeds of inferred deinonychosaurian affinity. Despite the lack of body fossils from the Dasheng Group in Shandong Province, a high diversity of deinonychosaur body fossils is known from the contemporary Jehol Biota from northeastern China. This similarity underscores the importance of the Shandong track assemblage as indicators of regional, tetrapod biodiversity during the Cretaceous

Clinical Application of SARS-CoV-2 IgM and IgG Antibody Detection Using the Colloidal Gold Immunochromatography Assay

The COVID-19 pandemic, which was caused by SARS-CoV-2, has had a significant effect on global public health, economies, and societies worldwide. Serum antibody testing is a critical method for the diagnosis of COVID-19 and can complement RT-PCR in the diagnosis of COVID-19 patients; however, the performance of rapid antibody assays in the clinical setting has not been established. Rapid antibody assays were evaluated by investigating 296 COVID-19-positive individuals and 542 negative individuals confirmed by clinical diagnosis. The clinical diagnostic results were used as controls to evaluate the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), kappa, and 95% confidence interval (CI) of the rapid tests. IgM-positivity had a sensitivity of 86.1% and specificity of 99.1%. IgG-positivity had a sensitivity of 86.5% and specificity of 98.7%. The sensitivity of combined IgM- and IgG-positivity in clinically confirmed patients was 73.1% in the early stage (1-7 days after symptom onset) and reached 99% 15 days after symptom onset. The concordance between rapid antibody-positive tests and clinical diagnosis-positivity had a kappa value of 0.93. In addition, the false-positive rate of IgM and IgG combined nucleic acid detection was 30% in the early stage. The combined use of IgM and IgG could serve as a more suitable alternative detection method for patients with COVID-19. The rapid antibody test can be considered as an excellent supplementary approach for detecting SARS-CoV-2 in clinical application

Design and analysis of 12 MW offshore wind turbine

Permanent magnet synchronous motors are widely used in various fields for the advantages of high power density, high efficiency and high reliability. This paper analyzes the cogging torque of generators with different slot and pole coordination, and selects the optimal pole–slot ratio. Then, this paper analyzes the structural differences between the outer rotor and the inner rotor of permanent magnet synchronous motor, and selects the structural form of the outer rotor for analysis. Based on the electromagnetic design parameters of the motor, a two-dimensional finite element model is established in Maxwell to simulate and analyze the performance at no-load, rated load and short-circuit. The internal magnetic field, the distortion rate of voltage waveform, torque and short circuit current of the motor are studied, and the demagnetization of the permanent magnet under the worst operating condition is investigated. The simulation results show that the design scheme meets the design objectives

Study on the effect of different pre-excitation factors on the output characteristics of MCSR

This paper takes the BKFSZT-30000/400 three-phase eight-limb magnetically controlled shunt reactor as the research object. Firstly, an electromagnetic transient simulation model is established based on the parity principle to verify the operating characteristics of the MCSR during direct energization and pre-excitation energization. On this basis, the influence of the pre-excitation capacity and the target capacity on the output characteristics of the MCSR is investigated. The results show that during the pre-excitation process the currents of working and control winding produce a DC component and a harmonic component dominated by the second harmonic, with the size of both DC components mainly influenced by the pre-excitation capacity and the attenuation determined by MCSR; the variation of the working harmonics is mainly influenced by the target capacity, while the size and attenuation of the control harmonics are determined by the pre-excitation capacity and the target capacity respectively. The results of the study clarify the output characteristics of the MCSR when energization with pre-excitation and provide a reference for further analysis of the interaction with the grid. Finally, to solve the problem of no reliable external power supply for pre-excitation, a fast excitation energization method with short-connected of the compensation winding is provided and verified by simulation

Pore Structure Multifractal Characteristics of Coal Reservoirs in the Central and Eastern Qinshui Basin and Influencing Factors

The heterogeneity of the pore structure of coal reservoirs affects the desorption and diffusion characteristics of coalbed methane, and determining its distribution law is conducive to improving the theory of coalbed methane development. The central and eastern parts of the Qinshui Basin are rich in coalbed methane resources, but the heterogeneity characteristics of the pore structure of coal reservoirs are not clear. NMR has the advantages of being fast, non-destructive and full-scale, and multifractal can describe the self-similarity of NMR T2 curve at different scales so as to analyze the complexity of pore distribution. Based on this, 15 samples with different coal ranks were collected from the central and eastern Qinshui Basin (Ro,max between 1.54 and 2.78%), and quantitative pore characterization experiments such as low-field nuclear magnetic resonance (LF-NMR) and low-temperature liquid nitrogen adsorption (LTN2A) were conducted. Based on multifractal theory, the heterogeneity law of pore structure was quantitatively evaluated, and its influencing factors were elucidated. The results showed that the BJH pore volume of coal samples in the study area ranged from 0.0005–0.0028 cm3/g, with an average of 0.0014 cm3/g, and the BET specific surface area was 0.07–2.52 m2/g, with an average of 0.41 m2/g. The NMR T2 spectrum peaked at 0.1–1, 10–100 and 100–1000 ms, and the spectrum was mostly bimodal or trimodal, indicating that pores of different pore sizes were developed. There were great differences in the pore structure of different coal ranks; high-rank coal was dominated by micropores, and the proportion of mesopores and macropores of medium-rank coal was higher. The pore structure of coal samples showed obvious multifractal characteristics, and the fractal characteristics of the sparse region (low-value information) were more significant; they dominated the pore distribution and had a stronger influence on the distribution of pore space. Pore structure heterogeneity is closely related to the degree of coalification, and with the increase in coalification, it is closely related to coal lithotype and quality, and high mineral and inertinite contents lead to the enhancement of pore structure heterogeneity in coal reservoirs, while Ro,max, Mad and vitrinite group contents have opposite effects. The research results provide theoretical guidance for the subsequent exploration and development of coalbed methane in the region

Diverse sauropod-theropod-dominated track assemblage from the Lower Cretaceous Dasheng Group of Eastern China: testing the use of drones in footprint documentation

The use of drones in the exploration and documentation of track surfaces in steep terrain, otherwise only accessible by time intensive climbing activity, is tested. Location is the Nanquan site, one of many now known footprint localities from the Lower Cretaceous Dasheng Group that has been recently exposed by local industrial excavation. It reveals an ichnofauna of sauropod, theropod, and ornithopod tracks and trackways occurring at multiple stratigraphic levels (at least 10) in a thin sequence of fine grained purple mudstones with thin sandstone units that are steeply inclined by >45°. It was therefore necessary and most efficient to map the track-bearing surfaces using drone photography. The majority of track-bearing levels reveal sauropod tracks (cf. Brontopodus, cf. Parabrontopodus), which on some surfaces are very abundant. Large theropod tracks (cf. Grallator) and ornithopod tracks (Caririchnium) also occur, but only on single horizons. The ichnofauna is evidence of repeated activity by large dinosaurs in a fluvio-lacustrine floodplain setting susceptible to periodic desiccation. The Naquan site forms part of an extensive Dasheng Group outcrop belt with multiple tracks sites, most of these containing multiple track-bearing levels. As a result of the investigation, drone techniques can be recommended as an additional tool for quick documentation, in order to get a general overview and map of the track surface. Details are relatively distinct on the achieved photographs, however, a precise study still needs direct examination and documentation by classical outline drawings or photogrammetry

Survival rates and mycobacterial burden in the lung and spleen.

<p>Animals were infected with 25 colony-forming units of <i>M</i>.<i>tb</i> Erdman strain. Group coloring in the survival graph is maintained throughout the article for comparability of data. One animal in BCG/Ad(im) group died accidently and is excluded from data analysis (<b>A</b>). Overall log-rank test for trend yielded p = 0.0247, but no statistical differences between groups. Colony-forming units (CFU) of mycobacteria was measured per gram of randomly selected tissue from different lung lobs or spleen at necropsy. CFU per right lung (<b>B</b>), left lung (<b>C</b>) and spleen (<b>D</b>) were presented in logarithmic numbers. P-values above lines indicate comparison between groups. Mann-Whitney rank test is used to compare differences relative to naïve group.</p

Experimental schema and plan.

<p>Depicting the timelines of vaccination (BCG priming at wk0 and AdHu5Ag85A boosting at wk14), <i>M</i>.<i>tb</i> infectious challenge (wk20) and fixed endpoint/autopsy (wk38). Scheduled times for clinical signs, blood work for acute phase protein measurement, chest X-ray and immune monitoring are indicated. Timelines during infection phase are referred relative to the 18 weeks post-challenge timepoint (indicated within parentheses).</p