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  • Author: Xue-Wei x
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A Load Outage Judgement Method Considering Voltage Sags
Open access
Experimental and Simulative Study on Accumulator Function in The Process of Wave Energy Conversion

Abstract

In this paper, a floating-buoy wave energy converter using hydrostatic transmission system is studied. The entire work progress of wave energy power generation device is introduced, and the hydraulic transmission principles are emphasized through the simulation to verify the feasibility of design principle of hydraulic transmission system. The mathematical model of the accumulator is established and applied in the AMEsim simulation. The simulation results show that the accumulator plays an important role in the wave power hydraulic transmission system and that the correct configuration of accumulator parameters can improve the rapidity and stability of the system work. Experimental results are compared with the simulation results to validate the correctness of the simulation results. This would provide a valuable reference to the optimal design of wave power generation.

Open access
Cloning and Expression of HBV Infection Related Novel Gene C12orf49

Abstract

Objective To clone, express and purify C12orf49 recombinant protein. To prepare rabbit anti-C12orf49 protein polyclonal antibody in order to further elucidate its biological function.

Methods PCR was used to amplify the gene C12orf49 in vitro. pET-32a (+)-C12orf49, the recombinant protein prokaryotic expression vector, was transformed into E. coli. IPTG was used as the inductive agent to obtain C12orf49 recombinant protein, and the recombinant protein was analyzed with sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE) and Western blot. Specific polyclonal antibody was derived from rabbits that immunized by recombinant protein. ELISA and Western blot were used to test its titer and specificity, respectively. MTT cell proliferation experiment was carried out to observe effect of the protein on proliferation of HepG2 cells.

Results The C12orf49 recombinant protein was expressed in a large quantity. Data of ELISA indicated that the titer of polyclonal antibody was higher than 1:1 280 000. And the antibody also had a good specificity, confirmed by Western blot. C12orf49 recombinant protein may had a advanced effect on the proliferation of HepG2 cells.

Conclusions Using C12orf49 recombinant protein, we can obtain the polyclonal antibody with great titer and good specificity. Human novel gene C12orf49 encoded protein could promote the proliferation of HepG2 cells.

Open access
Length-weight relationships of five Cultrinae fish species and two of their hybrids from China

Abstract

TThe length-weight relationships (LWRs) were determined for five freshwater fish species collected from Liangzi Lake, the Xi River and Longxi River in China, including Megalobrama amblycephala, Megalobrama skolkovii, Megalobrama pellegrini and Megalobrama terminalis belonging to the genus Megalobrama, as well as white Amur bream (Parabramis pekinensis) of the genus Parabramis. Three of these five species had no previous LWR estimates in the FishBase. The LWRs of hybrids from Megalobrama amblycephala ♀ × Parabramis pekinensis ♂ and Megalobrama amblycephala ♀ × Megalobrama terminalis ♂ were also reported for the first time.

Open access
Optimal Design and Numerical Simulation on Fish-Like Flexible Hydrofoil Propeller

Abstract

Hydrofoil is widely used in underwater vehicle for the excellent hydrodynamic characteristics. Currently, researches are mostly about the rigid hydrofoil while the flexible hydrofoil, like the caudal fin, has not been studied adequately. In this paper, the fish was regarded as the bionic object. Then the kinematics model to describe the fish swimming was put forward. A fin-peduncle propulsion mechanism was designed based on the kinematics model to achieve the similar sine curve swimming model. The propulsion mechanism was optimized by Matlab to reduce the deviation between the output curve of the fin-peduncle propulsion mechanism and the ideal motion trajectory. Moreover, the motion phase angles among flexible articulations are optimized to reduce fluid resistance and improve propulsive efficiency. Finally, the fish-like hydrofoil oscillation is simulated by fluid-solid coupling method based on the Fluent. It was shown that the optimized flexible fish-like oscillation could generate the motion that follows the similar law of sine. The propulsive efficiency of oscillating hydrofoil propeller is much higher than that of the screw propeller, and the flexible oscillation has higher propulsive efficiency than the rigid oscillation without obvious fluid resistance increase.

Open access
Screening of early diagnostic markers of gentamicin-induced acute kidney injury in canines

Abstract

Introduction

The value of neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (Kim-1), and liver-type fatty acid binding protein (L-FABP) was assessed in early diagnosis of gentamicin-induced acute kidney injury (AKI) in dogs.

Material and Methods

Subcutaneous gentamicin injection in 16 healthy adult beagles made the AKI model. Blood was sampled every 6 h to detect NGAL, Kim-1, L-FABP, and serum creatinine (SCr) concentrations. Kidney tissue of two dogs was taken before the injection, as soon as SCr was elevated (78 μmol/L), and when it had risen to 1.5 times the baseline, and haematoxylin-eosin staining and transmission electron microscopy (TEM) were used to observe changes.

Results

NGAL, Kim-1, and SCr levels were significantly increased (P < 0.05) at 18, 30, and 78 h post injection, but L-FABP concentration was not associated with renal injury. At the earliest SCr elevation stage, findings were mild oedema, degeneration, and vacuolisation in renal tubular epithelial cells in pathology, and mild cytoplasmic and mitochondrial oedema in TEM. At this time point, NGAL and Kim-1 concentrations were significantly increased (P < 0.05), indicating that these two molecules biomark early kidney injury in dogs. Using receiver operating characteristic curve analysis, their warning levels were > 25.31 ng/mL and > 48.52 pg/mL.

Conclusion

Plasma NGAL and Kim-1 above warning levels are early indicators of gentamicin-induced AKI in dogs.

Open access
NPS2390, a selective calcium-sensing receptor antagonist controls the phenotypic modulation of hypoxic human pulmonary arterial smooth muscle cells by regulating autophagy

Abstract

Background and Objectives

Calcium-sensing receptor (CaSR) is known to regulate hypoxia-induced pulmonary hypertension (HPH) and vascular remodeling via the phenotypic modulation of pulmonary arterial smooth muscle cells (PASMCs) in small pulmonary arteries. Moreover, autophagy is an essential modulator of VSMC phenotype. But it is not clear whether CaSR can regulate autophagy involving the phenotypic modulation under hypoxia.

Methods

The viability of human PASMCs was detected by cell cycle and BrdU. The expressions of proliferation protein, phenotypic marker protein, and autophagy protein in human PASMCs were determined by western blot.

Results

Our results showed that hypoxia-induced autophagy was considerable at 24 h. The addition of NPS2390 decreased the expression of autophagy protein and synthetic phenotype marker protein osteopontin and increased the expression of contractile phenotype marker protein SMA-ɑ and calponin via suppressing downstream PI3K/Akt/mTOR signal pathways.

Conclusions

Our study demonstrates that treatment of NPS2390 was conducive to inhibit the proliferation and reverse phenotypic modulation of PASMCs by regulating autophagy levels.

Open access
A Retrospective Study of Continuous Renal Therapy and Anticoagulation in Patients with Hemorrhagic Fever with Renal Syndrome

Abstract

Objective To observe the application of continuous renal replacement therapy (CRRT) and heparin anticoagulation in patients with HFRS, and to explore a more suitable anticoagulant strategy.

Methods Eighty-five severe-type patients (severe group) and 71 critical-type patients (critical group) were enrolled in this study. The frequency of CRRT was compared between the two groups; the frequency of CRRT treated with and without heparin anticoagulation and the frequency of hemorrhage and channel blood clotting induced by the two anticoagulant strategies were observed.

Results The frequency of CRRT in the critical group was higher than that in the severe group (P < 0.001). The frequency of CRRT initiated during the overlapping phases in the critical group was significantly higher than that of the severe group (P = 0.032). The total times of CRRT was 103, and 70 of them were treated with heparin anticoagulation. The frequencies of hemorrhage induced by heparin anticoagulation and no heparinization were 16 and 0, respectively, and the frequencies of channel blood clotting were 2 and 4, respectively.

Conclusions CRRT has been used extensively in the critical-type patients with HFRS. The heparin anticoagulation and no anticoagulant strategies should be used more rationally in patients treated with CRRT, according to the clinical characteristics of the disease.

Open access
Association of FOXP3 Gene Polymorphism with Chronic Hepatitis B in Chinese Population

Abstract

Objective The forkhead transcription factor FOXP3 is a key molecular which can mediate regulatory T cells immune-related inhibitory functions. Increased levels of FOXP3-positive Tregs in peripheral blood have been proved to be associated with a less favorable prognosis in various inflammatory diseases. It is of great interest to investigate the correlation between single nucleotide polymorphism (SNP) of FOXP3 gene and the susceptibility of chronic hepatitis B (CHB).

Methods Two SNPs rs2280883 and rs3761549 of FOXP3 gene in 285 patients with CHB and 295 matched controls were analyzed by Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF).

Results At rs2280883, there were no significant differences in the distribution of C and T alleles between CHB donors and healthy donors, but at rs3761549, C allele was associated with CHB (P = 0.001). Compared with healthy controls, patients with CHB had high frequencies of TT genotype (73.7%) at rs2280883 or CC genotype (73.6%) at rs3761549 of FOXP3 gene. Patients who carried rs2280883 CC genotype [OR 1.744 (95% CI 1.068 - 2.848), P = 0.011] or rs3761549 CC genotype [OR 1.633 (95% CI 1.146 - 2.327), P = 0.0001] had higher risk of suffering from CHB. Stratified analysis showed that rs3761549 CC genotype was significantly associated with high incidence of HBeAg (P = 0.019).

Conclusions These results suggested that FOXP3 gene polymorphism at rs2280883 and rs3761549 might be associated with the increased susceptibility to CHB.

Open access
Histopathological and cytopathological findings in minipigs infected with Streptococcus suis serotype 2

Abstract

Five pathogen-free miniature pigs (minipigs) were infected with the virulent strain SH08 of Streptococcus suis 2 (SS2) by intramuscular injection. The pigs died consecutively within 72 h after the challenge. An additional five non-infected pigs were euthanised and used as controls. Microstructural observations showed that degeneration, bleeding, congestion, cellular necrosis, and an increase in inflammatory cells were present in all organs and tissues except the brain. Ultrastructural observations revealed mitochondrial vacuolation and malformed or missing cristae, indicating that infection of minipigs with strain SH08 of SS2 can lead to extensive lesions in major internal organs and tissues. The findings also demonstrated that the minipig is a useful model for the study of SS2 infection.

Open access