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The effects of projectile/target impedance matching and projectile shape on energy, momentum transfer and projectile melting during collisions are investigated by numerical simulation. By comparing the computation results with the experimental results, the correctness of the calculation and the statistical method of momentum transfer coefficient is verified. Different shapes of aluminum, copper and heavy tungsten alloy projectiles striking aluminum, basalt, and pumice target for impacts up to 10 km/s are simulated. The influence mechanism of the shape of the projectile and projectile/target density on the momentum transfer was obtained. With an increase in projectile density and length-diameter ratio, the energy transfer time between the projectile and targets is prolonged. The projectile decelerates slowly, resulting in a larger cratering depth. The energy consumed by the projectile in the excavation stage increased, resulting in lower mass-velocity of ejecta and momentum transfer coefficient. The numerical simulation results demonstrated that for different projectile/target combinations, the higher the wave impedance of the projectile, the higher the initial phase transition velocity and the smaller the mass of phase transition. The results can provide theoretical guidance for kinetic impactor design and material selection.

This study conducted comparative analyses on impacting factors and effects of college student learning satisfaction between online and offline teaching mode. The results demonstrated that: 1) students' learning satisfaction for offline teaching mode was significantly higher than that for online mode; 2) teacher-student interaction, student-student interaction, course content and teacher quality were significantly positively correlated with both online and offline learning satisfaction, respectively. Furthermore, teacher-student interaction and student-student interaction positively predict offline learning satisfaction, while student-student interaction and teacher quality positively predict online learning satisfaction; 3) offline learning satisfaction significantly affected students' evaluation of learning outcomes as well as their preference of teaching mode. Specifically, the more satisfaction they had of offline teaching mode, the students were more likely to indicate the learning outcomes of offline courses was higher than that of online courses, and prefer to choose offline teaching mode as well as the blended teaching mode.

Lake-level changes can significantly affect paleoenvironmental evolution, resource occurrence, terrestrial carbon budget, and biodiversity in continental basins. Climate is one of the most critical factors controlling lake-level changes. Paleoclimate of the Early Jurassic has been evidenced by oscillating icehouses to (super) greenhouses with interrupted intermittent extreme climatic events (hyperthermal and cooling), e.g., the Toarcian oceanic anoxic event (~183 Ma) and the late Pliensbachian cooling event (~185 Ma). Lake-level evolution and hydrologic cycling on Earth’s surface during the Early Jurassic icehouses-to-(super)greenhouses are thus far poorly understood due to a lack of continuous high-resolution nonmarine evidence. Here we present a super-long nonmarine lake level record for this pivotal interval from the early Pliensbachian to Toarcian by sedimentary noise modeling, and construct a 16.7-Myr-long astronomical time scale (174.2 Ma to 190.9 Ma) based on cyclostratigraphy analysis of rock color datasets (CIE b*) of the Qaidam Basin. Our results document lake-level oscillations on a 5-to 10-million-year (Myr) scale which shows a pronounced correlation with long-term climate variation and extreme climatic events, and 1- to 2.5-Myr-scale lake-level changes that are prominently paced by the 2.4-Myr long-eccentricity forcing and the 1.2-Myr obliquity forcing. At the Pliensbachian Stage, the 1.2-Myr-scale lake-level changes are in phase with the coeval sea-level variations. Orbitally forced growth and decay of the ephemeral or permanent ice sheets in polar regions are interpreted to control the synchronous ups-and-downs of continental lake level and global sea level. However, during the Toarcian ice-free greenhouses to (super)greenhouses, the 1.2-Myr-scale lake-level variations show an anti-phase relationship with global sea level, indicating a ‘seesaw’ interaction between continental reservoirs (lakes and groundwater) and global oceans. The 2.4-Myr long-eccentricity cycles mainly regulate variations of lake level and sea level by controlling the growth and decay of small-scale continental ice sheets, which is especially notable during the Pliensbachian Stage. These findings indicate a remarkable transition of hydrological cycling pattern during the Pliensbachian-Toarcian icehouses to (super)greenhouses, which provides new perspectives and evidence for investigating the hypothesis of global sea-level changes (e.g., glacio-eustasy and aquifer-eustasy) and long-period astronomical forcing in nonmarine stratigraphy.

Duck-derived lactic acid bacteria(DDL) are a crucial beneficial bacterium in the intestines, contributing significantly to the health of ducks. However, the mechanism by which these DDL improves the growth performance and meat quality of Muscovy duck is not clear. In this study, A total of 800 male Muscovy ducks, initially weighing 50.15 ± 5.37 g, were randomly allocated into 4 groups, each with 4 replicates, consisting of 50 ducks per replicate. The control group consumed deep well water, while the experimental groups were given water supplemented with 1%, 3%, and 5% DDL (1.59×108CFU/mL). The study duration was 70 d. The results revealed that Muscovy ducks drinks with the DDL significant reduced the feed conversion ratio (FCR) (P< 0.05) and increased the sweetness and richness of duck meat, among which the 5% drinking group has the most significant difference. Further study finding, the DDL significantly increased the height of villi, the ratio of villi height/crypt depth (V/C) on jejunum and colon, and the ratio of acidic mucus, neutral mucus, and glycogen to tissue area in both the duodenum and ileum of Muscovy ducks, and significantly decreased the tunel positive cells. Moreover, DDL significantly enhanced the abundance of genus beneficial bacterium (Bacillus, lentilactobacillus, Bacterodies, Lactobacillus) on duodenum and ileum. Additionally, drink with the DDL elevated the level of IgG in blood and the immune indices of the thymus and the fabricius bursa (P<0.05). Meanwhile, the meat composition analysis demonstrated that Muscovy duck drinks with the DDL raised the level of the saturated fatty acid rate(C12:0), and polyunsaturated fatty acid (C18:2 n-6 and C20:5 n-3,), and the monounsaturated (C18:1 n-7, and C18:1 n-9). Furthermore, correlation analysis finding that the growth performance of Muscovy ducks was positively correlated with the height of villi, the ratio of villi height/crypt depth (V/C), the abundance of genus beneficial bacterium. And the meat quality of Muscovy ducks has positively correlated with genus beneficial bacterium in intestinal, glutamic acid, saturated fatty acid rate and polyunsaturated fatty acid. This finding suggest DDL is an effective strategy to improve the growth performance and meat quality of Muscovy ducks by gut histomorphology and intestinal microflora.

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P2Y14receptor (P2Y14R) is activated by uridine 5′-diphosphate-glucose, which is involved in many human inflammatory diseases. Based on the molecular docking analysis of currently reported P2Y14R antagonists and the crystallographic overlap study between the reported P2Y14R antagonist compounds 6and 9, a series of N-substituted-acetamide derivatives were designed, synthesized, and identified as novel and potent P2Y14R antagonists. The most potent antagonist, compound I-17(N-(1H-benzo[d]imidazol-6-yl)-2-(4-bromophenoxy)acetamide, IC50= 0.6 nM) without zwitterionic character, showed strong binding ability to P2Y14R, high selectivity, moderate oral bioactivity, and improved pharmacokinetic profiles. In vitroand in vivoevaluation demonstrated that compound I-17had satisfactory inhibitory activity on the inflammatory response of monosodium urate (MSU)-induced acute gouty arthritis. I-17decreased inflammatory factor release and cell pyroptosis through the NOD-like receptor family pyrin domain-containing 3 (NLRP3)/gasdermin D (GSDMD) signaling pathway. Thus, compound I-17, with potent P2Y14R antagonistic activity, in vitroand in vivoefficacy, and favorable bioavailability (F= 75%), could be a promising lead compound for acute gouty arthritis.

Dietary absorption and digestion are influenced by the microbiota, morphology, and digestive enzymes of intestines, and fermentation is a popular and effective technique to enhance animal rearing growth performance. This study aims to explore the pivotal role of Muscovy duck probiotics fermented feedstuff (FF) in altering the growth performance by reshaping gut morphology, microorganisms and metabolism. The findings showed that FF considerably raised the levels of fatty acids (FA) and small peptides (7-19AA) in the diet. Further feeding trial data reveals that FF greatly increased the Muscovy duck average daily gain (ADG) but had no effect on their daily feed intake (DFI), and the FCR significantly dropped (P< 0.05). Additionally, it was evident that FF improved the integrity of the intestinal mucosa in Muscovy duck by increasing villus height, villus height-to-crypt depth ratio, and lowering crypt depth. Then, in comparison to the control group (NC), there was a significant increase in the gene expression of the mucosal tight junction proteins Occludin, Claudin-1, and Zo-1 in the intestine of Muscovy duck. Additionally, there was higher expression of the mucosal transport channels SGLT-1, PepT1, AQP2, AQP3, and AQP10 in the similarly colon site, jejunum, and duodenum. Furthermore, in AB-PAS/PAS-stained duodenum, jejunum, ileum, and similarly colon site, FF markedly increased relative mucus output and goblet cells while decreasing epithelial cell apoptosis. Following 16S sequencing data indicated that the intestinal microbiota was altered and the diversity and richness of gut microbes was greatly enhanced by FF. Particularly, the boost of core probiotics, such as Rothiaof duodenum, Limosilactobacillusand Lentilactobacillusof jejunum, Lactococcus and Rothiaof ileum, Ligilactobacillus and Entocuccusof similarly colon site, Gallibacteriumof caecum. And reduced potentially pathogenic bacteria (Campylobacter, Prevotellaceae, Clostridia-vadinBB60,and Oscillospira). Nontargeted metabolomics assay for intestinal content confirmed an increased organic acids (oxidanesulfonic acid, cholic acid, gallic acid, coumaric acid, pipecollc acid, 13s-hydroxyoctadecadienoic acid) and glycosides metabolites (5-hydroxydantrolene, 3-hydroxyguanfacine glucuronide, acetylleucine, astragalin, xanthosine, taxiphylin, sinapine, denudatine, penylalanyl-tyrosine and phenylalanyl-valine). These findings demonstrated that FF, a viable option to improve Muscovy duck growth performance through reconstructed intestinal morphology, microorganisms, and metabolism, subsequently promoted the gut health and increased diet digestion and absorption. The study that is being presented offers scientific proof that FF might be a useful strategy for improving Muscovy duck growth performance.

Atherosclerotic cardiovascular disease remains a worldwide epidemic and one of the leading causes of death nowadays. Vessel wall imaging can be used to understand the development and progression of atherosclerosis, but it is rarely done because of the high cost. We recently identified the Osteoarthritis Initiative, a large prospective cohort study of knee osteoarthritis, which might serve as a valuable source for atherosclerosis research with its serial knee magnetic resonance imaging data. We have found that these images are suitable for vessel wall image analysis of the lower extremity arteries. Here, we will introduce the Osteoarthritis Initiative data set and explain why it could be used for cardiovascular research purposes. Also, we will briefly comment on peripheral artery atherosclerosis as it is covered in the Osteoarthritis Initiative image data set and review the use of vessel wall imaging for studying atherosclerosis. We think data mining of imaging studies, not originally designed on cardiovascular research, can not only maximize the value of the imaging data set but also boost our understanding of atherosclerosis.

Background:Renal fibrosis is a common outcome of nearly all kinds of chronic kidney disease (CKD) and eventually progresses to end-stage renal disease. The identification of an optimal biomarker of renal fibrosis to replace the invasive renal biopsy will have important clinical implications. Methods:We isolated urinary exosomes from 50 participants and examined the exosomal protein content and particle number in 38 CKD patients with different degrees of renal fibrosis and in 12 normal individuals. We examined the levels of exosomal microRNAs (miRNAs), namely, miR-200a, miR-200b, miR-200c, miR-141, miR-429, miR-29a, miR-29b, miR-29c, miR-192, and miR-21, by sorting the exosomes and comparing the levels of proximal tubular, non-proximal tubular, and total exosomal miR-200b. Results:The exosome content was higher in the CKD group, but no differences were evident among the mild, moderate, and severe fibrosis groups. Among the 10 exosomal miRNAs, miR-200b was lower in the CKD group than in the normal group and decreased more significantly with fibrosis progression as well as in IgA nephropathy and diabetic kidney disease. CD13+CD63+exosomes constituted 18.6% of all urinary exosomes. Sorting the proximal tubular exosomes with the CD13 protein marker revealed that miR-200b in the CD13+group was extremely low; however, the result was significantly different in the CD13–group but not in the CD13+group. The magnitude of the decline was greater in the CD13–groups than in the non-sorted whole groups between the fibrosis and normal patients. Conclusions:Non-proximal renal tubule-derived urinary exosomal miR-200b is a biomarker of renal fibrosis. Exosomes can be used as a liquid biopsy and may replace the traditional invasive renal biopsy in the diagnosis of renal fibrosis.

It is well known that using two or more deformable mirrors (DMs) can improve the compensation ability of an adaptive optics (AO) system. However, to keep the stability of an AO system, the correlation between the multiple DMs must be suppressed during the correction. In this paper, we proposed a slope-based decoupling algorithm to simultaneous control the multiple DMs. In order to examine the validity and practicality of this algorithm, a typical woofer-tweeter (W-T) AO system was set up. For the W-T system, a theory model was simulated and the results indicated in theory that the algorithm we presented can selectively make woofer and tweeter correct different spatial frequency aberration and suppress the cross coupling between the dual DMs. At the same time, the experimental results for the W-T AO system were consistent with the results of the simulation, which demonstrated in practice that this algorithm is practical for the AO system with dual DMs.

In this Letter, we present an adaptive aberration correction system to simultaneously compensate for aberrations and reshaping the beams. A low-order aberration corrector is adapted. In this corrector, four lenses are mounted on a motorized rail, whose positions can be obtained using a ray tracing method based on the beam parameters detected by a wavefront sensor. After automatic correction, the PV value of the wavefront is reduced from 26.47 to 1.91 μm, and the beam quality β is improved from 18.42 to 2.86 times that of the diffraction limit. After further correction with a deformable mirror, the PV value of the wavefront is less than 0.45 μm, and the beam quality is 1.64 times that of the diffraction limit. To the best of our knowledge, this is the highest performance from such a high-power, high-pulse repetition rate Nd:YAG solid-state laser ever built.

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Adaptive optics is an important technology for improving beam quality in solid-state slab lasers. However, there are uncorrectable aberrations in partial areas of the beam. In the criterion of the conventional least-squares reconstruction method, it makes the zones with small aberrations nonsensitive and hinders this zone from being further corrected. In this paper, a weighted least-squares reconstruction method is proposed to improve the relative sensitivity of zones with small aberrations and to further improve beam quality. Relatively small weights are applied to the zones with large residual aberrations. Comparisons of results show that peak intensity in the far field improved from 1242 analog digital units (ADU) to 2248 ADU, and beam quality β improved from 2.5 to 2.0. This indicates the weighted least-squares method has better performance than the least-squares reconstruction method when there are large zonal uncorrectable aberrations in the slab laser system.

Centimeters-long double-walled carbon nanotube strands were irradiated by a 355 nm pulsed laser. Multiwalled carbon nanofibers, hollow and solid onion-like nanoparticles, were found to be changed from DWNTs, induced by UV laser irradiation. As-grown Fe catalysts were also found to aggregate and were conveniently able to be removed by a dilute HCl solution. The structural changes in the DWNTs strand depend importantly on the laser energy input. On the basis of high-resolution transmission electronic microscope (HRTEM) observations, we propose a process of the structural change.

Diamond particles dispersed in the Fe-C alloy system were obtained by CO2continuous laser-induced quenching of C60/C70 coatings on 45# carbon steel (C content: 0.45 pct). Rockwell hardness, electron microscopy, and selected area electron diffraction methods had been used to analyze the products (namely, fullerite). The results indicated that the so-made fullerite, which reached average Rockwell hardness of 65.4, contained a great deal of polygonal crystallites on the order of 0.1 (μm). Most of them were well-faceted cubic diamond. Other new phases were also formed in the process. The possible transition mechanism was discussed.

ZnO-Bi2O3 based varistor ceramics doped with SnO2 or with SnO2, B2O3 and SiO2 were prepared by traditional solid-state reaction method respectively. The microstructure and properties of samples sintered at a low temperature range from 910 to 950degC were studied. Results show that: by low-temperature sintering, the sintering aids can improve the sample's density and homogeneity, and therefore the overall properties of the samples. It was found that the samples sintered at 910degC with SnO2 as sintering aid possess the best performance, and the breakdown voltage is 1368 V/mm, nonlinear coefficient is 12.2, and the leakage current is less than 0.1 uA.

We present a hybrid adaptive optics system for a kW-class solid-state slab master oscillator power amplifier laser that consists of both a low-order aberration corrector and a 59-actuator deformable mirror. In this system large defocus and astigmatism of the beam are first corrected by the low-order aberration corrector and then the remaining components are compensated by the deformable mirror. With this sequential procedure it is practical to correct the phase distortions of the beam (peak to valley up to 100 μm) and the beam quality β is successfully improved to 1.9 at full power.

A zonal decoupling algorithm used to control a dual deformable mirror (DM) is proposed. One of the two DMs is characterized with a large stroke (woofer), while the other one is characterized by a high spatial frequency (tweeter). A numerical model is used to compare the zonal decoupling algorithm with some traditional zonal decoupling algorithms. The simulation results indicate that the algorithm presented in this Letter improves the performance in suppressing the coupling error. An experimental system is built to prove the effectiveness of this algorithm. The experiments demonstrate that the phase aberrations could be effectively compensated and that the coupling error could also be suppressed.

A successful beam cleanup of a 5-mJ/200-µs pulsed solid-state laser system operating at 532-nm wavelength is demonstrated. In this beam cleanup system, a wave-front sensor-less adaptive optics (AO) system is set up with a 20-element bimorph mirror (BM), a high-voltage amplifier, a charge-coupled device camera, and a control software implementing the stochastic parallel gradient descent (SPGD) algorithm. The brightness of the laser focal spot is improved because the wave-front distortions have been compensated. The performance of this system is presented and the experimental results are analyzed.