Search

This paper proposed a technical idea of joint operation of conveying and grading and developed a potato conveying and grading device with variable space to realize efficient grading in the field because of the difficulties of field grading in the process of potato harvesting in the hilly mountains of northwest China. Based on field measurement of potato size distribution, the clearance between rotating plates of potato conveying and grading device was determined. The key structural parameters of the rotating plate were obtained by referring to the structure and relevant parameters of the conveying and grading device. Moreover, the conveyor chain elevation angle of the conveying and grading device was determined through the dynamics analysis of potatoes on the conveying and grading device. The inclined plane test determined the inclination angle of the potato guide plate. To reduce the damage to potatoes in the process of conveying and grading, damage analysis was carried out. Finally, Field tests were conducted with conveyor chain elevation angle, unit forward speed, and the conveyor chain line speed as test factors, and the grading accuracy and the damage rate of the potato conveying and grading device as test indexes. The test results showed that when the conveyor chain elevation angle, unit forward speed, and conveyor chain line speed were 21.0°, 0.8 m/s, and 1.3 m/s, respectively, the grading accuracy was 91.4% and the rate of potato damage was 0.88%. The operational performance of the prototype was stable, and all the test evaluation indicators could meet the agronomic requirements of the potato harvester.

Aims: This work reported a 405 nm photodetector based on the thermal evaporated CsPbBr3-CsPb2Br5 compound thin film. Background: The post-annealing process of the CsPbBr3-CsPb2Br5 compound thin film prepared by thermal evaporation method has been improved in this work. To enhance the crystallization and photoresponse properties of the thin films, dimethyl sulfoxide (DMSO) steam was used in post-annealing process, instead of using the previous way that increased the annealing temperature. Methods: The CsPbBr3-CsPb2Br5 compound powder was deposited directly on surface glass substrate by thermal evaporation to form CsPbBr3-CsPb2Br5 compound thin film. The thin films were post-annealed at 150 oC for 15 min to crystallize. The DMSO liquid was dropped on the substrate, and then the liquid would be evaporated completely to become DMSO steam during 150 oC post-annealing. The DMSO steam would cover the thin film completely to help the crystallization. Finally, the gold electrodes were deposited on surface of thin films with a conductive channel of 1 mm * 100 µm. Result: Results showed that the crystalline quality of the thin film after DMSO steam annealing was greatly improved compared with that of thin film without DMSO steam annealing. The energy gap was between 2.355 eV and 2.293 eV, which was similar to the previous report. In addition, under 405 nm excitation, the photocurrent of the thin film annealed in DMSO steam showed the rapid response (35 ms), good light radiation power dependence of the photocurrent and the improved responsivity. Especially, the responsivity at 3 V bias of the thin film annealed in DMSO steam increased to 1.5 times that of the thin film without DMSO steam annealing and even 4.5 times that of as-deposited film. Conclusion: A 405 nm photodetector based on the thermal evaporated CsPbBr3-CsPb2Br5 compound thin film was prepared successfully. The newest report has improved the preparation process of CsPbBr3-CsPb2Br5 compound thin films, where low annealing temperature with the DMSO steam assisted post-annealing process was used. The thin film annealed in DMSO steam possesses high crystalline quality and enhanced photoresponse performances, compared with thin film without DMSO steam annealing.

A dynamic field of study has emerged involving long-range electron transport by extracellular filaments in anaerobic bacteria, with Geobacter sulfurreducens being used as a model system. The interest in this topic stems from the potential uses of such systems in bioremediation, energy generation, and new bio-based nanotechnology for electronic devices. These conductive extracellular filaments were originally thought, based upon low-resolution observations of dried samples, to be type IV pili (T4P). However, the recently published atomic structure for the T4P from G. sulfurreducens, obtained by cryo-electron microscopy (cryo-EM), is incompatible with the numerous models that have been put forward for electron conduction. As with all high-resolution structures of T4P, the G. sulfurreducens T4P structure shows a partial melting of the α-helix that substantially impacts the aromatic residue positions such that they are incompatible with conductivity. Furthermore, new work using high-resolution cryo-EM shows that conductive filaments thought to be T4P are actually polymerized cytochromes, with stacked heme groups forming a continuous conductive wire, or extracellular DNA. Recent atomic structures of three different cytochrome filaments from G. sulfurreducens suggest that such polymers evolved independently on multiple occasions. The expectation is that such polymerized cytochromes may be found emanating from other anaerobic organisms.

In mammals, the signaling adaptor mitochondrial antiviral signaling protein (MAVS) is a critical determinant in antiviral innate immunity. However, because of the lack of in vivo data, the physiological function of zebrafish mavs in response to viral infection is still not determined. In this study, we demonstrate that the long splicing isoform of zebrafish mavs promotes IFN regulatory factor 3 signaling and NF-κB signaling. Overexpression of this isoform of mavs enhances cellular antiviral responses. Disruption of mavs in zebrafish attenuates survival ratio on challenge with spring viremia of carp virus. Consistently, the antiviral-responsive genes and inflammatory genes are significantly reduced, and the replication of spring viremia of carp virus is increased in mavs-null zebrafish. Therefore, we provide in vivo evidence to support that zebrafish mavs is essential for antiviral innate immunity, similar to mammalian MAVS.

Nano-kirigami method enables rich diversity of structural geometries that significantly broaden the functionalities of optical micro/nano-devices. However, the methodologies of various nano-kirigami are still limited and as a result, the chiral nano-kirigami structure has yet been pushed to the limit for operation at visible wavelength region. Here, the merits of the various nano-kirigami strategies are comprehensively explored and bio-inspired nano-cilia metasurface with enhanced circular dichroism at visible wavelengths is demonstrated. The stereo chiral nano-cilia metasurface is designed with three-fold rotational symmetry, which exhibits tuneable chiroptical responses when the nano-cilia are deformed to form strong chiral light–matter interactions. By employing electron-beam lithography (EBL) and focused ion beam (FIB) lithography, on-chip nano-cilia metasurfaces are experimentally realized in near-infrared wavelengths region and at visible wavelengths, respectively, successfully validating the giant circular dichroism revealed in simulations. Our work is useful to broaden the existing platform of micro/nano-scale manufacturing and could provide an effective method for the realization of versatile bioinspired nanostructures with profound chiroptical responses.

Gametophytic self-incompatibility (GSI) has been widely studied in flowering plants, but studies of the mechanisms underlying pollen tube growth arrest by self S-RNase in GSI species are limited. In the present study, two leucine-rich repeat extensin genes in pear (Pyrus bretschneideri), PbLRXA2.1 and PbLRXA2.2, were identified based on transcriptome and quantitative real-time PCR analyses. The expression levels of these two LRX genes were significantly higher in the pollen grains and pollen tubes of the self-compatible cultivar 'Jinzhui' (harboring a spontaneous bud mutation) than in those of the self-incompatible cultivar 'Yali'. Both PbLRXA2.1 and PbLRXA2.2 stimulated pollen tube growth and attenuated the inhibitory effects of self S-RNase on pollen tube growth by stabilizing the actin cytoskeleton and enhancing cell wall integrity. These results indicate that abnormal expression of PbLRXA2.1 and PbLRXA2.2 is involved in the loss of self-incompatibility in 'Jinzhui'. The PbLRXA2.1 and PbLRXA2.2 promoters were directly bound by the ABRE-binding factor PbABF.D.2. Knockdown of PbABF.D.2 decreased PbLRXA2.1 and PbLRXA2.2 expression and inhibited pollen tube growth. Notably, the expression of PbLRXA2.1, PbLRXA2.2, and PbABF.D.2 was repressed by self S-RNase, suggesting that self S-RNase can arrest pollen tube growth by restricting the PbABF.D.2-PbLRXA2.1/PbLRXA2.2 signal cascade. These results provide novel insight into pollen tube growth arrest by self S-RNase.

The question of whether narcissists are more creative than peers has attracted much scholarly attention in both psychology and organizational management sciences. Drawing from social cognitive theory, we theorized that the relationship between narcissism and creativity could be explained by individual creative self-efficacy, which depends on one's direct and vicarious experiences of creativity. Drawing from trait activation theory, we further proposed organizational valuing of creativity as a key contextual moderator that determines whether narcissism facilitates or inhibits creative self-efficacy and, in turn, creativity. We suggest that high organizational valuing of creativity will energize narcissists to put their attention and effort into both direct and vicarious experiences of creativity, enhancing their creative self-efficacy and creativity. We tested our conceptual model through a field study with data collected from 269 full-time employees working in 86 work teams. The empirical results provided support for the social cognitive explanation for the positive relationship between narcissism and creativity in the context of high organizational valuing of creativity. Our study not only resolved prior debates on the relationship between narcissism and creativity but also provided direct empirical support for social cognitive theory and the person-in-context interactionist perspective of creativity research.

The focus of this manuscript is to develop a facile method for the uniform preparation of heptavalent PAECs and to investigate the performance of heptavalent PAECs in immunoassays.