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In this paper, a hydraulic soft gripper for underwater applications is designed to provide a solution for improving the gripping force as well as the sensing capability of the soft gripper. The soft gripper is made of silicone and has an integrated semi-circular hydraulic network inside. To enhance the rigidity and grasping performance of the soft gripper, we have integrated a restriction layer consisting of a spring steel plate in the soft gripper. Meanwhile, to enhance the sensing capability of this soft gripper, we have designed a water pressure sensor based on resistance strain gauges and integrated it on the spring steel plate. Before fabrication, we determined the structural parameters of the soft gripper by geometric analysis. Then we experimentally evaluated its pressure-bearing capacity, bending performance, the role of spring steel plates, and the accuracy of the sensor.The experimental results show that the spring steel plate improves the gripping force of the soft gripper, the sensor also has high accuracy, and the built four-finger gripping system has good adaptability to objects of different shapes and weights.Compared with the existing solutions, this solution takes a simpler structural form while improving the gripping force and sensing ability of the soft gripper, and integrates the issues of improving the gripping force and sensing ability. The spring steel plate used in this paper not only improves the gripping force of the soft gripper but also provides a stable and reliable platform for installing sensors.

The mechanisms of colostrum-mediated virus transmission are difficult to elucidate because of the absence of experimental animal models and the difficulties in tissue sample collection from mothers in the peripartum period. Porcine epidemic diarrhea virus (PEDV) is a reemerging enteropathogenic coronavirus that has catastrophic impacts on the global pig industry. PEDV primarily infects neonatal piglets by multiple routes, especially 1- to 2-day-old neonatal piglets. Here, our epidemiological investigation and animal challenge experiments revealed that PEDV could be vertically transmitted from sows to neonatal piglets via colostrum, and CD3

Crossing the endothelium from the entry site and spreading in the bloodstream are crucial but obscure steps in the pathogenesis of many emerging viruses. Previous studies confirmed that porcine epidemic diarrhea virus (PEDV) caused intestinal infection by intranasal inoculation. However, the role of the nasal endothelial barrier in PEDV translocation remains unclear. Here, we demonstrated that PEDV infection causes nasal endothelial dysfunction to favor viral dissemination. Intranasal inoculation with PEDV compromised the integrity of endothelial cells (ECs) in nasal microvessels. The matrix metalloproteinase 7 (MMP-7) released from the PEDV-infected nasal epithelial cells (NECs) contributed to the destruction of endothelial integrity by degrading the tight junctions, rather than direct PEDV infection. Moreover, the proinflammatory cytokines released from PEDV-infected NECs activated ECs to upregulate ICAM-1 expression, which favored peripheral blood mononuclear cells (PBMCs) migration. PEDV could further exploit migrated cells to favor viral dissemination. Together, our results reveal the mechanism by which PEDV manipulates the endothelial dysfunction to favor viral dissemination and provide novel insights into how coronavirus interacts with the endothelium.

The EFG technique was used to successfully grow a crystal of Ho,Pr:Lu2O3. The crystal's spectroscopic features were investigated. Ho,Pr:Lu2O3 has an absorption cross-section of 0.47 × 10−20 cm2 at 647 nm and 0.20 × 10−20 cm2 at 1147 nm. The fluorescence characteristics of the grown crystal at 2.9 µm were examined using the J-O theory. Calculations were made for the intensity parameters Ωt (t = 2, 4, 6), radiative transition rates, branching ratios, and radiative lifetime. Ho,Pr:Lu2O3 demonstrated significant emission at 2104 and 2893 nm, with stimulated emission cross sections of 2.96 × 10−21 cm2 and 4.24 × 10−21 cm2, respectively. Ho3+ 5I6 and 5I7 levels were found to have fluorescence lifetimes of 0.55 ms and 3.23 ms, respectively.

Edge-defined film-fed growth (EFG) was successfully used to grow a Ho3+ doped Sc2O3 crystal. At room temperature, the spectroscopic characteristics of the Ho:Sc2O3 crystal were measured. At 650 nm, 1144 nm, and 1922nm, respectively, the peak absorption cross sections were 0.430 × 10−20 cm2, 0.159 × 10−20 cm2, and 0.513 × 10−20 cm2, with complete widths at half maximum of 16 nm, 22 nm, and 122 nm. The crystal's 5I7→5I8 and 5I6→5I7 peak emission cross-sections were 5.205 × 10−21 cm2 and 5.059 × 10−21 cm2, respectively. The measured fluorescence lifetimes 5I6 and 5I7 were 0.135 ms and 8.389 ms, respectively. The results demonstrated the great potential of Ho:Sc2O3 crystal for 3 µm laser operation.

Lymphocytes in the colostrum play many important roles during lactation, including protecting newborn piglets against infections. The lymphocytes constantly enter the mammary gland from the mother's bloodstream before and during lactation. However, little is known about the mechanism of transport of maternal lymphocytes across the mammary glands into the milk (lumen). In this study, the maternal lymphocytes were detected in sow colostrum by immunofluorescent staining and fluorescence-activated cell sorting and lymphocytes were observed transmigrating into the breast acinar lumen. Furthermore, immunohistochemical staining revealed that CD3+ T, γδ+ T, and IgA+ B cells were primarily located at the base area of the mammary gland. Meanwhile, more lactating alveoli and blood capillaries were distributed in this area. Finally, a mammary epithelial cell (EpH4-Ev)/T cell co-culture system was established to explore the mechanism of lymphocyte transmigration across the mammary epithelial cells. The expression of CCL2 and CCL28 in EpH4-Ev cells, which facilitated the transmigration of lymphocytes, significantly increased in the presence of prolactin. Our results provide a better understanding of the concept of lactogenic immunity and pave the way for vaccination strategies for the induction of lactogenic immunity in pregnant swine.

High-quality Cr:LuScO3 crystals were grown by the FZ (floating zone) method. The absorption spectra from 400 nm to 750 nm were tested at room temperature. The absorption cross-sections (σabs) of 0.5at.% and 1at.% Cr3+:LuScO3 were calculated to be 0.70×10−20 cm2 and 0.64×10−20 cm2 at 483 nm corresponding to the 4A2→4T1 transition, and 0.30×10−20 cm2 and 0.27×10−20 cm2 at 661 nm corresponding to the 4A2→4T2 transition, respectively. The transition Cr3+:4T2→4A2 in 1at.% Cr3+:LuScO3 exhibited a broad emission band with the FWHM value reaching up to 297 nm and the emission cross-section (σem) was 2.35×10−20 cm2. From the spectra, the crystal field parameter (Dq) was calculated to be 1513 cm-1, Racah B and C were 544 cm-1 and 3331 cm-1, respectively. All the results indicated the great application potential of Cr3+:LuScO3 crystals in the field of ultrafast lasers.

As the most abundant cell type in the blood, red blood cells (RBCs) are serving for transporting oxygen. However, the mechanism by which RBCs binding virus remains largely unknown. Here, we demonstrated that porcine epidemic diarrhea virus (PEDV), a kind of coronavirus, could hijack RBCs and cause typical diarrhea in neonatal piglets. In an epidemiology investigation of PEDV, the RBCs samples from diarrheic pigs in several pig farms were found to be PEDV-positive. PEDV could bind to neonatal RBCs through CD71 and clathrin-mediated endocytosis, and its viability was maintained for 12 h. PEDV-loaded RBCs could transfer the virus to CD3+ T cells by conjugation and reach the intestine mucosa, where it caused infection. Finally, a further animal challenge revealed that transfusing with PEDV-loaded RBCs could cause intestinal epithelial cells (IECs) infection and typical diarrhea symptom. Therefore, our studies illustrated the mechanism by which PEDV could cause intestinal infection through hijacking RBCs, further providing a novel insight into the role of RBCs as potential cells for viral transmission in coronavirus pathogenesis.

Porcine epidemic diarrhea virus (PEDV) causes acute and devastating intestinal disease in suckling piglets, resulting in a huge loss in the worldwide swine industry. Although several researches have reported that PEDV could cause viremia, the mechanism of how PEDV spread in the blood has been still unclear. Here, we showed PEDV could cause typical diarrhea in newborn piglets through hijacking red blood cells (RBCs). Firstly, PEDV could bind and internalize into neonatal RBCs through CD71 and clathrin-mediated endocytosis, and maintain its viability for 12 h. Subsequently, PEDV-loaded RBCs could transfer the virus to CD3+ T cells by formatting conjugation structure. PEDV could continue to hitchhike CD3+ T cells to reach intestine mucosa and cause infection. Moreover, after autotransfusion with PEDV-loaded RBCs, PEDV could infect and colonize intestinal epithelial cells, causing typical diarrhea symptoms in newborn piglets. Unintentionally, PEDV-loaded RBCs were found in nasal capillary after intranasal spraying with PEDV. Since oxygen partial pressure (pO2) and temperature of nasal cavity are different from other tissues, we further determined the higher pO2 was a promoting factor for PEDV binding RBCs. Therefore, the nasal capillary was speculated to be the entry for PEDV binding RBCs. Collectively, our studies illustrated the mechanism that PEDV could cause intestine infection through hijacking RBCs, further providing a novel insight into the role of RBCs in coronavirus pathogenesis as potential cells for viral transmission.

Sonar is an important means of underwater target detection. However, the existing sonar measurement method does not use a third-party object as a reference, which makes it difficult to measure underwater targets. In this paper, we propose an angle measurement method and a 3D mapping algorithm based on sonar images and artificial landmarks. By combining acoustic and visual methods, using the known size information of artificial landmarks as a reference, we can calculate the target information to realize the mapping between real space and sonar images. Before verifying the feasibility, we processed the sonar image, denoised it with a median filter, enhanced the landmark image with the Sauvola algorithm, and finally introduced two data fitting methods to extract the edge information of artificial landmarks, so as to help us find the key points more accurately. The experimental results show that the accuracy of our method can reach the millimeter level, and the error range is within 5%. The technology proposed in this paper realizes the shape correction and precise length measurement of underwater targets.

When vehicle road-level localization cannot satisfy people's need for convenience and safety driving, lane-level localization becomes a corner stone in Intelligent Transportation System. Existing works of tracking vehicles on lane-level mostly depend on pre-deployed infrastructures and additional hardwares. In this paper, we utilize smartphones to sense driving conditions for vehicle lane-level localization on highways. By analyzing driving traces collected from real driving environments, we find that each type of lane-change has its unique pattern on the vehicle's lateral acceleration. Based on this observation, we propose a Lane-Level Localization ( $L^3$ ) system, which can perform real-time vehicle localization on lane-level only using smartphones when vehicles are driving on highways. Our system first uses embedded sensors in smartphones to capture the patterns of lane-change behaviors. Then, a Finite State Machine is employed to track vehicles on lane-level leveraging the patterns. Extensive experiments demonstrate that $L^3$ is accurate and robust in real driving environments. The experimental results show that, on average, $L^3$ achieves the accuracy of 91.49 percent on lane change detection and 90.31 percent on lane-level localization.

A reaction strategy for the post-functionalization of hexavanadate derivatives is presented herein. In this study, five polyoxovanadate-based organic-inorganic hybrids TBA2[V6O13{(OCH2)3CCOO(CH2)15CH3}2] (2), TBA2[V6O13{(OCH2)3CCOO(CH2)8CH[double bond, length as m-dash]CH2}2] (3), TBA2[V6O13{(OCH2)3CCOOCH2CF3}2] (4), TBA2[V6O13{(OCH2)3CCOO(CH2CH2O)3CH3}2] (5), and TBA2[V6O13{(OCH2)3CCOO(CH2)12OH}2]·2CH3CH2OH (6) were successfully synthesized via esterification of carboxylic acid groups-containing TBA2[V6O13{(OCH2)3CCOOH}2] (1) with five alcohols possessing different functional groups. These hybrids were characterized by single crystal X-ray diffraction, IR, ESI-MS, 1H and 13C-NMR spectroscopies, and elemental analysis. Moreover, the formation of large vesicles was observed in a mixed solution of compound 2 due to its surfactant-like structure.

Due to the high rate of proppant flowback after hydraulic fracturing stimulations, surface modified quartz sand proppants with excellent proppant flowback control abilities, self-aggregating proppants, were prepared. These surface modified proppants can aggregate together spontaneously and form a proppant column in water based liquid environment. Analyses show that the strong hydrogen bonds contribute to the absorption of the surface modifier onto the proppants, and the softening effect of the water to the polymer coating prompts the connection between the proppants. Scanning electron microscope pictures show that proppant particles are stacked together tightly. The stable structure contributes to the macroscopic stability of the proppant column. The maximum sand free flow rate of the model packed with modified proppants is 2.8 times larger than that of untreated proppants by average, indicating that the self-aggregating proppants exhibit excellent proppant flowback control abilities. In addition, fines control tests show that the modified proppants can also prevent the migration of the formation fines effectively, reducing the conductivity loss caused by particle migrations. By virtue of the reaggreating property and the encapsulation action of polymer coating to the crushed fragments, the fracture conductivities are increased by 3 times even at large closure stresses. The results provide a new alternative for proppant flowback control while do little damage to the permeability of the proppant pack.

Chromium acetate-HPAM gel is developed to solve the gas channeling problem in low-permeability flue gas flooding reservoirs. Polyacrylamide with low molecular weight of 2 million is optimized as the main agent to construct an organic chromium gel system. The acid resistance performance and blocking capacity of the gel system are evaluated afterwards. It is revealed by the tests that acid components in flue gas have a severe impact on the gelation time, strength as well as long-term stability of the cross-linked gels. Rheological tests show that the gel system embodies with high elastic modulus in flue gas environment at 42°C, which ensures its favorable performance in core flooding tests. After gel application in cores, the permeability reduction can reach up to 99% and 97% separately while water flooding and flue gas flooding. The chromium acetate-HPAM gel exhibits perfect mobility control ability and possesses immense potential as regulating blocking system in low-permeability flue gas flooding reservoirs.

Unconsolidated sandstone reservoirs are susceptible to sanding problems. Traditional sand consolidation methods are often not environmental-friendly or ineffectively. This paper proposed a new sand consolidation treatment with aqueous-based self-healing system (ABSH) to maximize the sand free rate. The ABSH performs well with a relative lower dosage in laboratory tests. Sand consolidation performance and chemical resistance property were evaluated using the maximized sand free rate as indicators. After aging for 12 hours, the maximized sand free rate of consolidated sand pack could be prominently increased to 6600mL/h. Re-agglomeration ability between sand particles was illuminated by adhesion force tests. The adhesion force could be almost 90% of the original one after the contacting and separating process proceeded for three times.

Porcine reproductive and respiratory syndrome (PRRS), an economically significant pandemic disease, commonly results in increased impact of bacterial infections, including those by Streptococcus suis (S. suis). In recent years, PRRS virus (PRRSV) NADC30-like strain has emerged in different regions of China, and coinfected with S. suis and PRRSV has also gradually increased in clinical performance. However, the mechanisms involved in host innate responses towards S. suis and their implications of coinfection with NADC30-like strain remain unknown. Therefore, the pathogenicity of NADC30-like strain and S. suis serotype 2 (SS2) coinfection in vivo and in vitro was investigated in this study. The results showed that NADC30-like increased the invasion and proliferation of SS2 in blood and tissues, resulting in more severe pneumonia, myocarditis, and peritonitisas well as higher mortality rate in pigs. In vitro, NADC30-like strain increased the invasion and survival of SS2 in porcine alveolar macrophages (PAM) cells, causing more drastic expression of inflammatory cytokines and activation of NF-ĸB signalling. These results pave the way for understanding the interaction of S. suis with the swine immune system and their modulation in a viral coinfection.

Epidemiological investigations were conducted on recently emerging porcine reproductive and respiratory syndrome virus (PRRSV) strains in Shandong province in 2014–2015. The proportion of the NADC30 strain identified by ORF7 sequence alignment has been gradually increasing. Three emerging PRRSV strains were successfully isolated, and the complete genomic sequences were determined. Our results indicate the importance of recombinant strains in Shandong province, China. There was a varied degree of recombination of two or three strains (classical, HP-PRRSV and/or NADC30). Moreover, the recombination strains affected the pathogenicity of newly emerged strains.

In this study, a rapid and specific assay for the detection of porcine circovirus type 3 (PCV3) was established using loop-mediated isothermal amplification (LAMP). Four primers were specifically designed to amplify PCV3. The LAMP assay was effectively optimized to amplify PCV3 by water bath at 60°C for 60 min. The detection limit was approximately 1 × 101 copy in this LAMP assay. Compared to porcine circovirus type 2 (PCV2), both gE and gD genes of pseudorabies virus (PRV) and porcine parvovirus (PPV), the LAMP assay showed a high specific detection of PCV3. A visible detection method was developed using SYBR Green I to recognize the results rapidly. Based on the detection of 20 clinical tissue samples, the LAMP assay was more practical and convenient than classical PCR due to its simplicity, high sensitivity, rapidity, specificity, visibility and cost efficiency.