This paper proposed an algorithm of collision detection based on a hybrid model which was different from other collision detection model. In this model, different box was used according to different occasion. And the algorithm of intersection calculation between bounding boxes was analyzed and finally the optimization of collision detection based on the hybrid model was gained.
Copper-catalyzed aerobic oxidative esterification of P(O)–OH compounds is achieved using alcohols as efficient esterification reagents, giving the expected products with good to moderate yields. Furthermore, it is shown that the arylation of P(O)–OH compounds proceeds efficiently to produce the corresponding products via the treatment of diaryliodonium triflates under mild reaction conditions. It is a simple way to produce a broad spectrum of functionalized phosphinates, phosphonates, and phosphates from basic starting materials with good to excellent yields. The protocol is convenient for practical application. A plausible mechanism has been proposed for the reaction.
Abstract Viral myocarditis caused by Coxsackievirus B (CVB) infection is a severe inflammatory disease of the myocardium, which may develop to cardiomyopathy and heart failure. No effective medicine is available to treat CVB infection. Here we evaluated the anti-CVB effect of N-acetyl cysteine (NAC), a widely used antioxidant. NAC significantly alleviated myocarditis and improved the overall condition of CVB type 3 (CVB3)-infected mice. Importantly, NAC treatment suppressed viral replication in both myocardium and cell culture. We show that NAC inhibited CVB3 replication when it was applied at the early stage of CVB3 infection. NAC’s antiviral mechanism, while independent of its antioxidant property, relies on its inhibition on caspase-1 activation, since the knockdown of caspase-1 blocked CVB3 replication. Moreover, NAC promotes procaspase-1 degradation via ubiquitin proteasome system, which may further contribute to the inhibited activity of caspase-1. NAC also inhibits the activity of viral proteases. Taken together, this study shows that NAC exerts potent anti-CVB effect by inhibiting caspase-1 and viral proteases. This study suggests that NAC can be a safe therapeutic option for CVB-induced myocarditis.
Electrochemical reduction of N2 to NH3 under ambient conditions can provide an alternative to the Haber–Bosch process for distributed NH3 production that can be powered by renewable electricity. The major challenge for realizing such a process is to develop efficient electrocatalysts for the N2 reduction reaction (N2RR), as typical catalysts show a low activity and selectivity due to the barrier for N2 activation and the competing hydrogen evolution reaction (HER). Here we report an Fe/Fe3O4 catalyst for ambient electrochemical NH3 synthesis, which was prepared by oxidizing an Fe foil at 300 °C followed by in situ electrochemical reduction. The Fe/Fe3O4 catalyst exhibits a Faradaic efficiency of 8.29% for NH3 production at −0.3 V vs the reversible hydrogen electrode in phosphate buffer solution, which is around 120 times higher than that of the original Fe foil. The high selectivity is enabled by an enhancement of the intrinsic (surface-area-normalized) N2RR activity by up to 9-fold as well as an effective suppression of the HER activity. The N2RR selectivity of the Fe/Fe3O4 catalyst is also higher than that of Fe, Fe3O4, and Fe2O3 nanoparticles, suggesting Fe/Fe oxide composite to be an efficient catalyst for ambient electrochemical NH3 synthesis.
Electroreduction of CO2 to formate on Bi-based catalyst is a promising route for CO2 recycling and sustainable fuel production. The use of gas-diffusion-electrode (GDE) flow cells has generally improved the rate of CO2 electrolysis, while the local reaction environment in GDEs and its impact on the electrolysis remain to be understood. Here, we report that tuning the microenvironment of Bi-based catalyst in a GDE by adding hydrophobic polytetrafluoroethylene (PTFE) nanoparticles in the catalyst layer can substantially enhance CO2 electrolysis, achieving a partial current density of 677 mA cm–2 for formate production and 35% single-pass CO2 conversion at −0.7 V versus RHE under 9-sccm CO2 gas flow. It is revealed that a moderate hydrophobicity of the catalyst layer can establish a microenvironment with a balance between gaseous CO2 and liquid electrolyte inside the catalyst layer, which reduces the diffusion layer thickness to accelerate CO2 mass transport and forms highly active reaction zones near solid–liquid–gas interfaces.
The SAUR (small auxin-up RNA) gene family is the biggest family of early auxin response genes in higher plants and has been associated with the control of a variety of biological processes. Although SAUR genes had been identified in several genomes, no systematic analysis of the SAUR gene family has been reported in Chinese white pear. In this study, comparative and systematic genomic analysis has been performed in the SAUR gene family and identified a total of 116 genes from the Chinese white pear. A phylogeny analysis revealed that the SAUR family could be classified into four groups. Further analysis of gene structure (introns/exons) and conserved motifs showed that they are diverse functions and SAUR-specific domains. The most frequent mechanisms are whole-genome duplication (WGD) and dispersed duplication (DSD), both of which may be important in the growth of the SAUR gene family in Chinese white pear. Moreover, cis-acting elements of the PbrSAUR genes were found in promoter regions associated with the auxin-responsive elements that existed in most of the upstream sequences. Remarkably, the qRT-PCR and transcriptomic data indicated that PbrSAUR13 and PbrSAUR52 were significantly expressed in fruit ripening. Subsequently, subcellular localization experiments revealed that PbrSAUR13 and PbrSAUR52 were localized in the nucleus. Moreover, PbrSAUR13 and PbrSAUR52 were screened for functional verification, and Dangshan pear and frandi strawberry were transiently transformed. Finally, the effects of these two genes on stone cells and lignin were analyzed by phloroglucinol staining, Fourier infrared spectroscopy, and qRT-PCR. It was found that PbrSAUR13 promoted the synthesis and accumulation of stone cells and lignin, PbrSAUR52 inhibited the synthesis and accumulation of stone cells and lignin. In conclusion, these results indicate that PbrSAUR13 and PbrSAUR52 are predominantly responsible for lignin inhibit synthesis, which provides a basic mechanism for further study of PbrSAUR gene functions.
Transposons of the Tc1/mariner family have been used to integrate foreign DNA stably into the genome of a large variety of different cell types and organisms.Integration is at TA dinucleotides located essentially at random throughout the genome, potentially leading to insertional mutagenesis, inappropriate activation of nearby genes, or poor expression of the transgene.Here, we show that fusion of the zinc-finger DNA-binding domain of Zif268 to the C-terminus of ISY100 transposase leads to highly specific integration into TA dinucleotides positioned 6-17 bp to one side of a Zif268 binding site.We show that the specificity of targeting can be changed using Zif268 variants that bind to sequences from the HIV-1 promoter, and demonstrate a bacterial genetic screen that can be used to select for increased levels of targeted transposition.A TA dinucleotide flanked by two Zif268 binding sites was efficiently targeted by our transposase-Zif268 fusion, suggesting the possibility of designer 'Z-transposases' that could deliver transgenic cargoes to chosen genomic locations.