Development of Tactile Imaging for Underwater Structural Damage Detection.

Underwater structural damage inspection has mainly relied on diver-based visual inspection, and emerging technologies include the use of remotely operated vehicles (ROVs) for improved efficiency. With the goal of performing an autonomous and robotic underwater inspection, a novel Tactile Imaging System for Underwater Inspection (TISUE) is designed, prototyped, and tested in this paper. The system has two major components, including the imaging subsystem and the manipulation subsystem. The novelty lies in the imaging subsystem, which consists of an elastomer-enabled contact-based optical sensor with specifically designed artificial lighting. The completed TISUE system, including optical imaging, data storage, display analytics, and a mechanical support subsystem, is further tested in a laboratory experiment. The experiment demonstrates that high-resolution and high-quality images of structural surface damage can be obtained using tactile 'touch-and-sense' imaging, even in a turbid water environment. A deep learning-based damage detection framework is developed and trained. The detection results demonstrate the similar detectability of five damage types in the obtained tactile images to images obtained from regular (land-based) structural inspection.

The mRNA Vaccine Expressing Single and Fused Structural Proteins of Porcine Reproductive and Respiratory Syndrome Induces Strong Cellular and Humoral Immune Responses in BalB/C Mice.

PRRS is a viral disease that profoundly impacts the global swine industry, causing significant economic losses. The development of a novel and effective vaccine is crucial to halt the rapid transmission of this virus. There have been several vaccination attempts against PRRSV using both traditional and alternative vaccine design development approaches. Unfortunately, there is no currently available vaccine that can completely control this disease. Thus, our study aimed to develop an mRNA vaccine using the antigens expressed by single or fused PRRSV structural proteins. In this study, the nucleotide sequence of the immunogenic mRNA was determined by considering the antigenicity of structural proteins and the stability of spatial structure. Purified GP5 protein served as the detection antigen in the immunological evaluation. Furthermore, cellular mRNA expression was detected by immunofluorescence and western blotting. In a mice experiment, the Ab titer in serum and the activation of spleen lymphocytes triggered by the antigen were detected by ELISA and ICS, respectively. Our findings demonstrated that both mRNA vaccines can significantly stimulate cellular and humoral immune responses. More specifically, the GP5-mRNA exhibited an immunological response that was similar to that of the commercially available vaccine when administered in high doses. To conclude, our vaccine may show promising results against the wild-type virus in a natural host.

Ssc-miR-7139-3p suppresses foot-and-mouth disease virus replication by promoting degradation of 3Cpro through targeting apoptosis-negative regulatory gene Bcl-2.

Foot-and-mouth disease is a highly contagious and infectious disease affecting cloven-hoofed animals. Disease control is complicated by its highly contagious nature and antigenic diversity. Host microRNAs (miRNAs) are post-transcriptional regulators that either promote or repress viral replications in virus infection. In the present study, we found that ssc-miR-7139-3p (Sus scrofa miR-7139-3p) was significantly up-regulated in host cells during foot-and-mouth disease virus (FMDV) infection. Overexpression of miR-7139-3p attenuated FMDV replication, whereas inhibition promoted FMDV replication. In addition, the survival rate of FMDV infected suckling mice was increased through injection of miR-7139-3p agomiR. Further studies revealed that miR-7139-3p targets Bcl-2 to initiate the apoptotic pathway and caspase-3 cleaved 3Cpro behind the 174th aspartic acid (D174), which eventually promotes the degradation of 3Cpro. Overall, our findings demonstrate that miR-7139-3p suppresses FMDV replication by promoting degradation of 3Cpro through targeting the apoptosis-negative regulatory gene Bcl-2.

Experimental Study on Compressive Behavior of Concrete Cylinders Confined by a Novel Hybrid Fiber-Reinforced Polymer Spiral.

Modern fiber-reinforced polymer (FRP)-reinforced concrete structures are excepted to achieve superior mechanical performances and long service lives, even in harsh service environments. Hybrid FRP material could potentially meet this goal with its relatively high strength-to-cost ratio. This paper presents an experimental study on the compressive behavior of concrete cylinders confined by a novel hybrid fiber-reinforced polymer (HFRP) spiral. Nine types, forming a total of 27 confined or non-confined concrete cylinders, were subjected to an axial compressive-loading test. Concrete cylinders confined either with different spiral types or different spiral spacings were comparatively studied in the experiment. The results showed that the compressive failure modes and the stress-strain relationships of the HFRP-spiral-confined cylinders were similar to those of basalt-fiber-reinforced polymer (BFRP)-spiral-confined cylinders. The actual fracture strain of the HFRP spiral (tested as a single rod) was larger than that of the corresponding carbon-fiber-reinforced polymer (CFRP) bar, indicating the advantageous composite effect of the HFRP spiral. The maximum strain of the HFRP spiral reached over 70% of its ultimate strain in the cylinders compared to the BFRP spiral, which only reached 50%. Most of the existing models overestimated the ultimate stress and strain of the HFRP-spiral-confined cylinders. Wu's model was proved to be the most accurate model, yet proper modification was required for predicting the peak strain of the HFRP-confined cylinders.

Knockout of HDAC9 Gene Enhances Foot-and-Mouth Disease Virus Replication.

Foot-and-mouth disease virus (FMDV) is a highly contagious viral disease that mainly infects cloven-hoofed animals. Propagation of FMDV by cell culture is an important method to preserve viral biological and antigenic characteristics, which is crucial in FMD monitoring and vaccine production. However, only a few cell lines are sensitive to FMDV, and there is still a lot of room for improvement. Acetylation is an important post-translational modification, which is dynamically regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs). However, the study of the relationship between FMDV and HDACs is still unclear. HDAC9 belongs to the class II of HDACs family; in this study, HDAC9 knockout (KO) BHK-21 cells were successfully established using CRISPR/cas9 technology. The results of karyotype analysis, growth curve analysis, and morphological observation showed that the HDAC9 knockout cell line was stable in growth and morphological characteristics. After infection with FMDV, the expression of viral RNA and protein, viral titers, and the copies of viral RNA in HDAC9-KO cells were significantly higher than those in NC cells. Meanwhile, RNA-seq technology was used to sequence HDAC9-KO cells and NC cells infected and uninfected with FMDV. It was found that the differentially expressed innate immune factors containing NFKBIA, SOD2, IL2RG, BCL2L1, CXCL1/2/3, and IL1RAP have significantly enriched in the Jak-STAT, NOD-like receptor, Toll-like receptor, NF-κB, and MAPK signaling pathway. RT-qPCR was performed to detect the expression level of differentially expressed genes and showed consistency with the RNA-seq data. These results preliminarily reveal the role of HDAC9 in host antiviral innate immune response, and the HDAC9-KO cell line could also serve as a useful tool for FMDV research.

Host microRNA miR-1307 suppresses foot-and-mouth disease virus replication by promoting VP3 degradation and enhancing innate immune response.

MicroRNAs (miRNAs) play important regulatory roles during interactions between virus pathogens and host cells, but whether and how they work in the case of foot-and-mouth disease virus (FMDV) is less understood. Based on a microarray-based miRNA profiling in the porcine kidney cell line PK-15, we identified 36 differentially expressed host miRNAs at the early stage of FMDV infection, among which miR-1307 was significantly induced. Functional characterization demonstrated that miR-1307 attenuated FMDV replication. Further experiments proved that miR-1307 specifically promoted the degradation of the viral structural protein VP3 indirectly through proteasome pathway. Moreover, innate immune signaling was activated and expression of immune responsive genes was significantly enhanced in the miR-1307-overexpressing clones. Together, our data demonstrated that miR-1307 suppresses FMDV replication by destabilizing VP3 and enhancing host immune response. Importantly, subcutaneous injection of miR-1307 agomir delayed the FMDV-induced lethality in suckling mice, exhibiting its therapeutic potential to control foot-and-mouth disease (FMD).