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The transcription factor (TF)‐mediated regulatory network controlling lincomycin production in Streptomyces lincolnensis is yet to be fully elucidated despite several types of associated TFs having been reported. SLCG_2919, a tetracycline repressor (TetR)‐type regulator, was the first TF to be characterized outside the lincomycin biosynthetic cluster to directly suppress the lincomycin biosynthesis in S. lincolnensis. In this study, improved genomic systematic evolution of ligands by exponential enrichment (gSELEX), an in vitro technique, was adopted to capture additional SLCG_2919‐targeted sequences harboring the promoter regions of SLCG_6675, SLCG_4123‐4124, SLCG_6579, and SLCG_0139‐0140. The four DNA fragments were confirmed by electrophoretic mobility shift assays (EMSAs). Reverse‐transcription quantitative polymerase chain reaction (RT‐qPCR) showed that the corresponding target genes SLCG_6675 (anthranilate synthase), SLCG_0139 (LysR family transcriptional regulator), SLCG_0140 (beta‐lactamase), SLCG_6579 (cytochrome P450), SLCG_4123 (bifunctional DNA primase/polymerase), and SLCG_4124 (magnesium or magnesium‐dependent protein phosphatase) in ΔSLCGL_2919 were differentially increased by 3.3‐, 4.2‐, 3.2‐, 2.5‐, 4.6‐, and 2.2‐fold relative to those in the parental strain S. lincolnensis LCGL. Furthermore, the individual inactivation of these target genes in LCGL reduced the lincomycin yield to varying degrees. This investigation expands on the known DNA targets of SLCG_2919 to control lincomycin production and lays the foundation for improving industrial lincomycin yields via genetic engineering of this regulatory network. [ABSTRACT FROM AUTHOR]

The graphene-contained materials are added during the synthesis process of polyester resin, thus a graphene modified polyester resin is prepared. It is revealed that the introduction of graphene has no effect on the synthesis process and parameters of polyester resin, in addition, has no effect on the properties of powder coatings, such as levelling property, bending property and reactivity. However, the mechanical and durability properties of powder coatings are decreased slightly. The self-made heat-radiating device is used to investigate the graphene modified powder coatings. The results show that the addition of graphene can significantly increase the heat radiation of powder coatings. Moreover, the heat radiation property increases with the increase of the film thickness in a certain range. [ABSTRACT FROM AUTHOR]

Based on the alkali resistance of polyester/TGIC, polyester/HAA, polyester/epoxy and polyurethane powder coatings, the hydroxy-terminated polyester resin is modified by means of using some monomer containing steric groups and improving the crosslinking density. The results show that polyester/TGIC and polyester/HAA systems have the worst alkali resistance, polyester/epoxy system is slightly better, and polyurethane system is the best. The modified hydroxy-terminated polyester resin has good mechanical properties, adhesion, boiling water resistance and excellent alkali resistance. At 30 °C, soaked by 50%wt NaOH for 96 h, the gloss retention rate is 77% with no cracking and other defects. At 60 °C, soaked by 50%wt NaOH for 22 h, the gloss retention rate is 60% with no cracking and other defects. [ABSTRACT FROM AUTHOR]

To solve the pollution problems that result from polypropylene (PP), suitable biopolymers such as poly (lactic acid) (PLA) were selected to blend with PP. Since PP/PLA blends are often exposed to the natural environment, it is necessary to study the photodegradation behavior of PP/PLA blends. In this paper, PP/PLA blends with different compositions were prepared by extrusion and subjected to the accelerated laboratory weathering equipment. The effects of compatibilizers on the degradation behavior of PP/PLA blends were also studied. The weatherability of PP/PLA blends was studied through weight loss, optical microscope, Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The results revealed that PP is easy to degrade than PLA during accelerated laboratory weathering. PP/PLA blends are susceptible to the accelerated laboratory weathering process, and PP-rich and PLA-rich blends reduce the weathering resistance. Moreover, the results indicate that the initial degradation temperature, melting temperature, and crystallization temperature decrease after weathering related to the decreased thermal stability of PP/PLA blends. For instance, the initial degradation temperature of PP/PLA8.2 reduces from 332.2 °C to 320.2 °C. Moreover, the compatibilized sample is generally more resistant to weathering conditions than the uncompatibilized one due to the higher compatibility of PP and PLA. [ABSTRACT FROM AUTHOR]

The parameter server architecture has shown promising performance advantages when handling deep learning (DL) applications. One crucial issue in this regard is the presence of stragglers, which significantly retards DL training progress. Previous solutions for solving stragglers may not fully exploit the computation resource of the cluster as evidenced by our experiments, especially in the heterogeneous environment. This motivates us to design a heterogeneity-aware parameter server paradigm that addresses stragglers and accelerates DL training from the perspective of computation parallelism. We introduce a novel methodology named straggler projection to give a comprehensive inspection of stragglers and reveal practical guidelines to solve this problem in two aspects: (1) controlling each worker's training speed via elastic training parallelism control and (2) transferring blocked tasks from stragglers to pioneers to fully utilize the computation resource. Following these guidelines, we propose the abstraction of parallelism as an infrastructure and design the Elastic-Parallelism Synchronous Parallel (EPSP) algorithm to handle distributed training and parameter synchronization, supporting both enforced- and slack-synchronization schemes. The whole idea has been implemented into a prototype called Falcon which effectively accelerates the DL training speed with the presence of stragglers. Evaluation under various benchmarks with baseline comparison demonstrates the superiority of our system. Specifically, Falcon reduces the training convergence time, by up to 61.83, 55.19, 38.92, and 23.68 percent shorter than FlexRR, Sync-opt, ConSGD, and DynSGD, respectively. [ABSTRACT FROM AUTHOR]

Big data analytics in datacenters often involve scheduling of data-parallel jobs. Traditional scheduling techniques based on improving network resource utilization are subject to limited bandwidth in datacenter networks. To alleviate the shortage of bandwidth, some cluster frameworks employ techniques of traffic compression to reduce transmission consumption. However, they tackle scheduling in a coarse-grained manner at task level and do not perform well in terms of flow-level metrics due to high complexity. Fortunately, the abstraction of coflow pioneers a new perspective to facilitate scheduling efficiency. In this paper, we introduce a coflow compression mechanism to minimize the completion time in data-intensive applications. Due to the NP-hardness, we propose a heuristic algorithm called Fastest-Volume-Disposal-First (FVDF) to solve this problem. For online applicability, FVDF supports stage pipelining to accelerate scheduling and exploits recurrent neural networks (RNNs) to predict compression speed. Meanwhile, we build ${\sf Swallow}$ Swallow , an efficient scheduling system that implements our proposed algorithms. It minimizes coflow completion time (CCT) while guaranteeing resource conservation and starvation freedom. The results of both trace-driven simulations and real experiments show the superiority of our algorithm, over existing one. Specifically, ${\sf Swallow}$ Swallow speeds up CCT and job completion time (JCT) by up to $1.47 \times$ 1. 47 × and $1.66 \times$ 1. 66 × on average, respectively, over the SEBF in Varys, one of the most efficient coflow scheduling algorithms so far. Moreover, with coflow compression, ${\sf Swallow}$ Swallow reduces data traffic by up to 48.41 percent on average. [ABSTRACT FROM AUTHOR]

Among the vinyl chloride production processes, ethane oxychlorination is the most economical and environment-friendly process but constrained by the lack of high performance catalysts for industrial applications. In this work, FeCl3–KCl/Al2O3 catalysts with different molar ratios of K/Fe were prepared by a co-impregnation method and applied to ethane oxychlorination. The FeCl3–KCl/Al2O3 catalyst with K/Fe = 2 exhibited enhanced catalytic performance with the highest conversion of C2H6 (99.1%) and the best selectivity to C2H3Cl (74%) under the optimal conditions of 400 °C, C2H6 : HCl : air = 1 : 3 : 5.5 (volume ratio) and GHSV = 4560 h−1. It was found that the enhanced catalytic performance could be attributed to the formation of KFeCl4 from KCl and FeCl3 and the change of the reaction process. Besides, KCl is in favor of weakening the interaction between the active species and support. The reduction activation energy of Fe(iii) → Fe(ii) is efficiently reduced by KCl addition. The FeCl3–KCl/Al2O3 catalyst may be a potential catalyst for industry due to its simple composition and convenient preparation. [ABSTRACT FROM AUTHOR]

Molybdenum diselenide (MoSe 2) have attracted much attention as an anode material for lithium/sodium ion batteries due to its specific layered structure. Here, highly-uniform MoSe 2 nanoparticles are successfully synthesized via a one-pot hydrothermal method with addition of polyvinyl pyrrolidone (PVP) following by calcination treatment. PVP serves as a surfactant preventing the over-agglomeration of MoSe 2 nanosheets and contributing to the well-organized accumulation of MoSe 2 nanosheets into nanoparticles. When evaluated as anode for lithium ion batteries, the MoSe 2 nanoparticles show enhanced cycle stability and rate performance comparing to the MoSe 2 bulk prepared without addition of PVP. After 200 cycles, the MoSe 2 nanoparticles remain a specific capacity of 573.9 mAh g−1 at a rate of 200 mA g−1. Meanwhile, MoSe 2 nanoparticles also display good sodium storage performance. Under the current density of 500 mA g−1, MoSe 2 nanoparticles exhibit reversible capacity of 374.9 mA h g−1 after 100 cycles. [Display omitted] • Highly-uniform MoSe2 nanoparticles are successfully synthesized via a simple method. • The effect of PVP during the particle formation has been studied in detail. • The as-prepared MoSe2 nanoparticles show enhanced electrochemical performance as anode materials. [ABSTRACT FROM AUTHOR]

We announce here the first complete chloroplast genome sequence of Tetrastigma planicaule, one important Chinese folk medicinal plant. This complete chloroplast genome is 160,323 bp in length. In total, 131 genes were identified, including 86 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The results of phylogenetic analysis indicated that Tetrastigma is a separate genus and is closely related to Vitis. [ABSTRACT FROM AUTHOR]

Supported perovskite promoted catalysts La 2 NiMnO 6 –CuCl 2 /γ-Al 2 O 3 and La 1.7 K 0.3 NiMnO 6 –CuCl 2 /γ-Al 2 O 3 were prepared by mechanical mixing method, and characterized by XRD, H 2 -TPR, XRF, XPS and magnetization techniques. The catalyst doped with potassium La 1.7 K 0.3 NiMnO 6 –CuCl 2 /γ-Al 2 O 3 possesses a large amount of Mn 4+ and surface-adsorbed oxygen species, which accelerate the oxidation of Cu + by a circular reaction and increase the release of Cl 2 , and therefore promote the conversion of C 2 H 6 and the selectivity to C 2 H 3 Cl. The catalyst La 1.7 K 0.3 NiMnO 6 –CuCl 2 /γ-Al 2 O 3 shows better catalytic activity for ethane oxychlorination with the C 2 H 6 conversion of 100% and the C 2 H 3 Cl selectivity to 59.4%. The total selectivity to C 2 H 4 and C 2 H 3 Cl maintains over 81% in 95 h. This study points out a potential way to develop more active perovskite-type oxide catalysts for ethane oxychlorination. [ABSTRACT FROM AUTHOR]

Real-time video perception tasks are often challenging on resource-constrained edge devices due to the issues of accuracy drop and hardware overhead, where saving computations is the key to performance improvement. Existing methods either rely on domain-specific neural chips or priorly searched models, which require specialized optimization according to different task properties. These limitations motivate us to design a general and task-independent methodology, called Patch Automatic Skip Scheme (PASS), which supports diverse video perception settings by decoupling acceleration and tasks. The gist is to capture inter-frame correlations and skip redundant computations at patch level, where the patch is a non-overlapping square block in visual. PASS equips each convolution layer with a learnable gate to selectively determine which patches could be safely skipped without degrading model accuracy. Specifically, we are the first to construct a self-supervisory procedure for gate optimization, which learns to extract contrastive representations from frame sequences. The pre-trained gates can serve as plug-and-play modules to implement patch-skippable neural backbones, and automatically generate proper skip strategy to accelerate different video-based downstream tasks, e.g., outperforming state-of-the-art MobileHumanPose in 3D pose estimation and FairMOT in multiple object tracking, by up to 9.43 × and 12.19 × speedups, respectively, on NVIDIA Jetson Nano devices.

To solve the pollution problems that result from polypropylene (PP), suitable biopolymers such as poly (lactic acid) (PLA) were selected to blend with PP. Since PP/PLA blends are often exposed to the natural environment, it is necessary to study the photodegradation behavior of PP/PLA blends. In this paper, PP/PLA blends with different compositions were prepared by extrusion and subjected to the accelerated laboratory weathering equipment. The effects of compatibilizers on the degradation behavior of PP/PLA blends were also studied. The weatherability of PP/PLA blends was studied through weight loss, optical microscope, Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The results revealed that PP is easy to degrade than PLA during accelerated laboratory weathering. PP/PLA blends are susceptible to the accelerated laboratory weathering process, and PP-rich and PLA-rich blends reduce the weathering resistance. Moreover, the results indicate that the initial degradation temperature, melting temperature, and crystallization temperature decrease after weathering related to the decreased thermal stability of PP/PLA blends. For instance, the initial degradation temperature of PP/PLA8.2 reduces from 332.2 °C to 320.2 °C. Moreover, the compatibilized sample is generally more resistant to weathering conditions than the uncompatibilized one due to the higher compatibility of PP and PLA., Competing Interests: The authors declare no conflict of interest.

Among the vinyl chloride production processes, ethane oxychlorination is the most economical and environment-friendly process but constrained by the lack of high performance catalysts for industrial applications. In this work, FeCl 3 -KCl/Al 2 O 3 catalysts with different molar ratios of K/Fe were prepared by a co-impregnation method and applied to ethane oxychlorination. The FeCl 3 -KCl/Al 2 O 3 catalyst with K/Fe = 2 exhibited enhanced catalytic performance with the highest conversion of C 2 H 6 (99.1%) and the best selectivity to C 2 H 3 Cl (74%) under the optimal conditions of 400 °C, C 2 H 6  : HCl : air = 1 : 3 : 5.5 (volume ratio) and GHSV = 4560 h -1 . It was found that the enhanced catalytic performance could be attributed to the formation of KFeCl 4 from KCl and FeCl 3 and the change of the reaction process. Besides, KCl is in favor of weakening the interaction between the active species and support. The reduction activation energy of Fe(iii) → Fe(ii) is efficiently reduced by KCl addition. The FeCl 3 -KCl/Al 2 O 3 catalyst may be a potential catalyst for industry due to its simple composition and convenient preparation.