3,390 research outputs found
EXPERIMENTAL STUDY OF TWO LARGE-SCALE MODELS’ SEAKEEPING PERFORMANCE IN COASTAL WAVES
Actual sea waves and vessel motion are an unsteady nonlinear random process. The currently adopted test to simulate wave impact of vessel models in tank can\u27t fully reveal the impact of real sea waves on vessel swing motion. In this paper the buoy wave height meter is adopted to carry out measurements and analyses of the coastal wave environment. The correlation between the coastal wave spectra and the ocean wave spectra is analyzed. The test system is established for remote control and telemetry self-propelled vessel models suitable for the experiment conducted in the coastal areas. The seakeeping performance test is conducted for the same tonnage of round bilge vessel model and the deep-V hybrid monohull of large-scale vessel model under the coastal wave conditions. The experimental results are compared with the test results of small-scale vessel model in the towing tank. The experimental results show that the seakeeping performance of the deep-V hybrid monohull is improved by a wide margin in contrast to that of the round bilge model, and there is a marked difference between the motion characteristics of large-scale vessel models in the coastal wave environment and that of small-scale vessel models in tank
A new stripe rust resistance gene transferred from Thinopyrum intermedium to hexaploid wheat (Triticum aestivum)
Wheat stripe rust (Puccinia striiforis f. sp. tritici) races CYR31 and CYR32, prevalent in China, are virulent to many wheat stripe rust resistance genes (Yr genes). To expand the availability of effective resistance to CYR31 and CYR32, stripe rust resistance was transferred from intermediate wheatgrass (Thinopyrum intermedium) to common wheat (Triticum aestivum). The susceptible wheat cultivar CM107 was crossed with amphiploid TAI7047, derived from the wide cross Taiyuan768/Thinopyrum intermedium//76(64). Two wheat lines originating from the cross, YU24 and YU25, were resistant to CYR31 and CYR32. Pedigree analysis showed that the resistance to stripe rust in YU24 and YU25 originated from intermediate wheatgrass. Genetic analyses indicated that the resistance to stripe rust is controlled by a single dominant gene. Allelic tests determined that the resistance gene(s) in YU24 and YU25 are identical. The new gene has temporarily been designated as YrYU25. SSR and RAPD analyses showed that YrYU25 was introduced by cryptic translocation into common wheat.Les races CYR31 et CYR32 de la rouille jaune du blé (Puccinia striiforis f. sp. tritici), très répandues en Chine, sont virulentes pour plusieurs gènes de résistance à cette maladie (gènes Yr). Afin d'accroître la disponibilité d'une résistance efficace aux races CYR31 et CYR32, la résistance à la rouille jaune du blé a été transférée de l'agropyre intermédiaire (Thinopyrum intermedium) au blé tendre (Triticum aestivum). CM107, un cultivar de blé sensible, a été croisé avec l'amphiploïde AI7047 dérivé du croisement éloigné Taiyuan768/Thinopyrum intermedium//76(64). Deux lignées de blé provenant de ce croisement, soit YU24 et YU25, étaient résistantes aux races CYR31 et CYR32. Une analyse généalogique a démontré que la résistance à la rouille jaune du blé chez les lignées YU24 et YU25 provenait de l'agropyre intermédiaire. Des analyses génétiques ont indiqué que cette résistance était contrôlée par un seul gène dominant. Des tests d'allélisme ont révélé que le(s) gène(s) de résistance dans les lignées YU24 et YU25 étaient identiques. Le nouveau gène a temporairement été nommé YrYU25. Des analyses SSR et RAPD ont démontré que le gène YrYU25 avait été introduit dans le blé tendre par translocation cryptique
Seeing through the Brain: Image Reconstruction of Visual Perception from Human Brain Signals
Seeing is believing, however, the underlying mechanism of how human visual
perceptions are intertwined with our cognitions is still a mystery. Thanks to
the recent advances in both neuroscience and artificial intelligence, we have
been able to record the visually evoked brain activities and mimic the visual
perception ability through computational approaches. In this paper, we pay
attention to visual stimuli reconstruction by reconstructing the observed
images based on portably accessible brain signals, i.e., electroencephalography
(EEG) data. Since EEG signals are dynamic in the time-series format and are
notorious to be noisy, processing and extracting useful information requires
more dedicated efforts; In this paper, we propose a comprehensive pipeline,
named NeuroImagen, for reconstructing visual stimuli images from EEG signals.
Specifically, we incorporate a novel multi-level perceptual information
decoding to draw multi-grained outputs from the given EEG data. A latent
diffusion model will then leverage the extracted information to reconstruct the
high-resolution visual stimuli images. The experimental results have
illustrated the effectiveness of image reconstruction and superior quantitative
performance of our proposed method.Comment: A preprint version of an ongoing wor
Elastic Valley Spin Controlled Chiral Coupling in Topological Valley Phononic Crystals
Distinct from the phononic valley pseudo-spin, the real physical spin of
elastic waves adds a novel tool-kit capable of envisaging the valley-spin
physics of topological valley phononic crystals from a local viewpoint. Here,
we report the observation of local elastic valley spin as well as the hidden
elastic spin-valley locking mechanism overlooked before. We demonstrate that
the selective one-way routing of valley phonon states along the topological
interface can be reversed by imposing the elastic spin meta-source at different
interface locations with opposite valley-spin correspondence. We unveil the
physical mechanism of selective directionality as the elastic spin controlled
chiral coupling of valley phonon states, through both analytical theory and
experimental measurement of the opposite local elastic spin density at
different interface locations for different transport directions. The elastic
spin of valley topological edge phonons can be extended to other topological
states and offers new tool to explore topological metamaterials.Comment: 5 pages, 3 figures, of main text + supplementary 10 figures. To be
published in Phys. Rev. Let
Aspirin-triggered lipoxin A4 attenuates LPS-induced pro-inflammatory responses by inhibiting activation of NF-ÎşB and MAPKs in BV-2 microglial cells
<p>Abstract</p> <p>Background</p> <p>Microglial activation plays an important role in neurodegenerative diseases through production of nitric oxide (NO) and several pro-inflammatory cytokines. Lipoxins (LXs) and aspirin-triggered LXs (ATLs) are considered to act as 'braking signals' in inflammation. In the present study, we investigated the effect of aspirin-triggered LXA<sub>4 </sub>(ATL) on infiammatory responses induced by lipopolysaccharide (LPS) in murine microglial BV-2 cells.</p> <p>Methods</p> <p>BV-2 cells were treated with ATL prior to LPS exposure, and the effects of such treatment production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), interleukin-1β (IL-1β) and tumour necrosis factor-α (TNF-α) were analysed by Griess reaction, ELISA, western blotting and quantitative RT-PCR. Moreover, we investigated the effects of ATL on LPS-induced nuclear factor-κB (NF-κB) activation, phosphorylation of mitogen-activated protein kinases (MAPKs) and activator protein-1 (AP-1) activation.</p> <p>Results</p> <p>ATL inhibited LPS-induced production of NO, IL-1β and TNF-α in a concentration-dependent manner. mRNA expressions for iNOS, IL-1β and TNF-α in response to LPS were also decreased by ATL. These effects were inhibited by Boc-2 (a LXA<sub>4 </sub>receptor antagonist). ATL significantly reduced nuclear translocation of NF-κB p65, degradation of the inhibitor IκB-α, and phosphorylation of extracellular signal-regulated kinase (ERK) and p38 MAPK in BV-2 cells activated with LPS. Furthermore, the DNA binding activity of NF-κB and AP-1 was blocked by ATL.</p> <p>Conclusions</p> <p>This study indicates that ATL inhibits NO and pro-inflammatory cytokine production at least in part via NF-κB, ERK, p38 MAPK and AP-1 signaling pathways in LPS-activated microglia. Therefore, ATL may have therapeutic potential for various neurodegenerative diseases.</p
EVALUATION OF WIND AND WAVE ENVIRONMENT ADAPTABILITY OF SHIPS
The environment adaptability especially integrated sailing performance in rough sea of ships is very important. In this paper the evaluation index system and method of wind and wave environment adaptability were proposed. Then the relative importance of the given indices was analyzed, and the weighting coefficients of the indices were given by estimation matrixes. Besides this the evaluation equation was built. And the AHP method and the method based on fuzzy theory were used for evaluating the environment adaptability of a hybrid monohull and a round bilge monohull. Furthermore, the effect of different models and weighting coefficients given by different matrixes for evaluation results were analyzed. The research indicated that the choice of evaluating parameters had great influence on the evaluation results, and the weighting coefficients were the difficult point but critical point for environment adaptability evaluation of ships
Theoretical Vibration Analysis on 600  
This paper shows a theoretical vibration analysis regarding the controller’s parameters and the gyroscopic effect, based on a simplified rotordynamic model. Combined with 600 Wh energy storage flywheel rotor system mathematical model, the Campbell diagram of the rotor system was obtained by the calculation of the whirl frequency under different parameters of the controller in MATLAB to analyze the effect of the controller parameter on the whirl frequency and to limit the operating speed and acceleration or deceleration of the rotor. The result of the analysis can be used to set the support position of the rotor system, limit the ratio of transverse moment of inertia and the polar moment of inertia, and direct the flywheel prototype future design. The presented simplified rotordynamic model can also be applied to rotating machines
Disodium ÎĽ-triethylenetetraaminehexa-acetato-bis[oxovanadate(IV)] hexahydrate
The crystals structure of the title heterometallic coordination compound, Na-2[(C18H24N4O12)(VO)(2)].6H(2)O, is built of Na+ cations, binuclear [C18H24N4O12(VO)(2)](2-) dianions and water molecules. The cations and anion occupy special positions at inversion centers. The V atom has an octahedral coordination environment formed by the vanadyl oxo atom [V=O 1.618 (3) Angstrom], two N [V - N 2.174 (4) and 2.289 (4) Angstrom] and three O atoms [V - O 1.993 (3), 1.998 (3) and 2.001 (3) Angstrom] of the amino-carboxylato group
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