Enhanced Gradient-Based Local Feature Descriptors by Saliency Map for Egocentric Action Recognition

Egocentric video analysis is an important tool in healthcare that serves a variety of purposes, such as memory aid systems and physical rehabilitation, and feature extraction is an indispensable process for such analysis. Local feature descriptors have been widely applied due to their simple implementation and reasonable efficiency and performance in applications. This paper proposes an enhanced spatial and temporal local feature descriptor extraction method to boost the performance of action classification. The approach allows local feature descriptors to take advantage of saliency maps, which provide insights into visual attention. The effectiveness of the proposed method was validated and evaluated by a comparative study, whose results demonstrated an improved accuracy of around 2%

Process Design of Microalgae Slurry Pump

Microalgae are a renewable source of dietary supplements, bioactive compounds, and potential energy. Once harvested, the microalgal medium is dewatered to form a slurry for downstream processing. This article outlines a process design for pumping the microalgae slurry. The pump requirements for delivering the Chlorella slurry with 5, 10 or 20 wt% solids at one tonne per hour (1,000 kg/h) and 10 bar were calculated. The 5 wt% microalgae slurry is a Newtonian fluid with a viscosity of 1.95 mPa×s. The 10 wt% and 20 wt% microalgae slurries are non-Newtonian fluids, whose viscosity depends on the shear rate (g). The viscosity of 10 wt% and 20 wt% microalgae slurries is 1.504 (g = 50 s-1)/1.155 (g = 100 s-1) and 1.844 (g = 50 s-1)/1.219 (g = 100 s-1) mPa×s, respectively. The pump power requirements are mainly governed by the delivery pressure. The effect of the pipe length and the number of elbows is negligible. The effective power of the pump is calculated as 0.267-0.275 kW. To fulfill this duty, a ZGB type single-stage single-suction centrifugal slurry pump can be selected, which would provide enough shear rate to reduce the viscosity of the microalgae slurry and give required shaft power. Citation: Li, J., Qu, Y., Gong, Y., Yang, C., Yang, B., Liu, P., Zhang, B., and Ding, Y. (2020). Process Design of Microalgae Slurry Pump. Trends in Renewable Energy, 6(3), 234-244. DOI: 10.17737/tre.2020.6.3.0012

Novel DNA Aptamers for Parkinson’s Disease Treatment Inhibit a-Synuclein Aggregation and Facilitate its Degradation

Parkinson\u27s disease (PD) is one of the most prevalent forms of synucleinopathies, and it is characterized neuropathologically by the presence of intracellular inclusions composed primarily of the protein α-synuclein (α-syn) in neurons. The previous immunotherapy targeting the α-syn in PD models with monoclonal antibodies has established α-syn protein as an effective target for neuronal cell death. However, due to the essential weaknesses of antibody and the unique features of aptamers, the aptamers could represent a promising alternative to the currently used antibodies in immunotherapy for PD. In this study, the purified human α-syn was used as the target for in vitro selection of aptamers using systematic evolution by exponential enrichment. This resulted in the identification of two 58-base DNA aptamers with a high binding affinity and good specificity to the α-syn, with KD values in the nanomolar range. Both aptamers could effectively reduce α-syn aggregation in vitro and in cells and target the α-syn to intracellular degradation through the lysosomal pathway. These effects consequently rescued the mitochondrial dysfunction and cellular defects caused by α-syn overexpression. To our knowledge, this is the first study to employ aptamers to block the aberrant cellular effects of the overexpressed α-syn in cells

Genetic Basis and Expression Pattern Indicate the Biocontrol Potential and Soil Adaption of Lysobacter capsici CK09

Lysobacter species have attracted increasing attention in recent years due to their capacities to produce diverse secondary metabolites against phytopathogens. In this research, we analyzed the genomic and transcriptomic patterns of Lysobacter capsici CK09. Our data showed that L. capsici CK09 harbored various contact-independent biocontrol traits, such as fungal cell wall lytic enzymes and HSAF/WAP-8294A2 biosynthesis, as well as several contact-dependent machineries, including type 2/4/6 secretion systems. Additionally, a variety of hydrolytic enzymes, particularly extracellular enzymes, were found in the L. capsici CK09 genome and predicted to improve its adaption in soil. Furthermore, several systems, including type 4 pili, type 3 secretion system and polysaccharide biosynthesis, can provide a selective advantage to L. capsici CK09, enabling the species to live on the surface in soil. The expression of these genes was then confirmed via transcriptomic analysis, indicating the activities of these genes. Collectively, our research provides a comprehensive understanding of the biocontrol potential and soil adaption of L. capsici CK09 and implies the potential of this strain for application in the future

Computation Rate Maximization for Wireless Powered Edge Computing With Multi-User Cooperation

The combination of mobile edge computing (MEC) and radio frequency-based wireless power transfer (WPT) presents a promising technique for providing sustainable energy supply and computing services at the network edge. This study considers a wireless-powered mobile edge computing system that includes a hybrid access point (HAP) equipped with a computing unit and multiple Internet of Things (IoT) devices. In particular, we propose a novel muti-user cooperation scheme to improve computation performance, where collaborative clusters are dynamically formed. Each collaborative cluster comprises a source device (SD) and an auxiliary device (AD), where the SD can partition the computation task into various segments for local processing, offloading to the HAP, and remote execution by the AD with the assistance of the HAP. Specifically, we aims to maximize the weighted sum computation rate (WSCR) of all the IoT devices in the network. This involves jointly optimizing collaboration, time and data allocation among multiple IoT devices and the HAP, while considering the energy causality property and the minimum data processing requirement of each device. Initially, an optimization algorithm based on the interior-point method is designed for time and data allocation. Subsequently, a priority-based iterative algorithm is developed to search for a near-optimal solution to the multi-user collaboration scheme. Finally, a deep learning-based approach is devised to further accelerate the algorithm's operation, building upon the initial two algorithms. Simulation results show that the performance of the proposed algorithms is comparable to that of the exhaustive search method, and the deep learning-based algorithm significantly reduces the execution time of the algorithm.Comment: Accepted to IEEE Open Journal of the Communications Societ

Enhancing production of lipase MAS1 from marine Streptomyces sp. strain in Pichia pastoris by chaperones co-expression

Background: A thermostable lipase MAS1 from marine Streptomyces sp. strain was considered as a potential biocatalyst for industrial application, but its production level was relatively low. Here, the effect of chaperones co-expression on the secretory expression of lipase MAS1 in Pichia pastoris was investigated. Result: Co-expression of protein disulfide isomerase (PDI), HAC1 and immunoglobulin binding protein could increase the expression level of lipase MAS1, whereas co-expression of Vitreoscilla hemoglobin showed a negative effect to the lipase MAS1 production. Among them, PDI co-expression increased lipase MAS1 expression level by 1.7-fold compared to the control strain harboring only the MAS1 gene. Furthermore, optimizing production of lipase MAS1 with Pichia pastoris strain X-33/MAS1-PDI in a 30-L bioreactor were conducted. Lower induction temperature was found to have a benefit effect for lipase MAS1 production. Lipase activity at 24 and 22\ub0C showed 1.7 and 2.1-fold to that at 30\ub0C, respectively. Among the induction pH tested, the highest lipase activity was obtained at pH 6.0 with activity of 440 U/mL after 144 h fermentation. Conclusion: Our work showed a good example for improving the production of recombinant enzymes in Pichia pastoris via chaperon co-expression and fermentation condition optimization

Inhibitory effects of adenovirus mediated tandem expression of RhoA and RhoC shRNAs in HCT116 cells

<p>Abstract</p> <p>Background</p> <p>RhoA and RhoC are deregulated by over expression in many human tumors, including colorectal cancer. Some reports show that they play a pivotal role in the carcinogenesis, tumor development and infiltration metastasis. In this study, for the first time we constructed recombinant adenovirus to investigate the inhibitory effects of RhoA and RhoC shRNAs in tandem expression on the cell proliferation and invasion of colorectal cancer HCT116 cells.</p> <p>Methods</p> <p>The recombinant adenovirus carrying RhoA and RhoC shRNAs in tandem expression was transfected into HCT116. The mRNA transcription and protein expressions of RhoA and RhoC were examined by RT-FQPCR and Western blot respectively. Cellular proliferation inhibitory activity was determined by methyl thiazolyl tetrazolium (MTT) assay and invasive and migrating potential was detected through in vitro Matrigel coated invasion and migration assay.</p> <p>Results</p> <p>Both mRNA and proteins Levels of RhoA and RhoC were significantly reduced in HCT116 cells transfected with Ad-A1+A2+C1+C2 than those in Ad-HK group and control one. The relative RhoA and RhoC mRNA transcriptions were decreased to 40% and 36% (P < 0.05), while proteins expression reducing 42% and 35%, respectively (P < 0.05). Growth curves analysis showed that alive cell number in the Ad-A1+A2+C1+C2 group was lower than others in the third to sixth day and transwell chamber analysis showed that migration/invasion activity was significantly suppressed in Ad-A1+A2+C1+C2 group.</p> <p>Conclusion</p> <p>Our results indicate recombinant adenovirus carrying RhoA and RhoC shRNAs in tandem expression may inhibit the growth and invasion of HCT116 cells. Application of such vector to inhibit one or more genes may be a new method to cancer therapy.</p