Search

The H9N2 avian influenza virus has been widely spread in poultry around the world. It is proved to the world that the avian influenza virus can directly infect human beings without any intermediate host adaptation in “1997 Hong Kong avian influenza case,” which shows that the avian influenza virus not only causes significant losses to the poultry industry but also affects human health. In this study, we aimed to address the problem of low protection of avian H9N2 subtype influenza virus vaccine against H9N2 wild-type virus. We have rescued the H9.4.2.5 branched avian influenza virus isolated in South China by reverse genetics technology. We have recombined these virus (rHA/NA-GD37 and rHA/NA-GD38) which contain hemagglutinin and neuraminidase genes from the H9N2 avian influenza virus (MN064850 or MN064851) and 6 internal genes from the avian influenza virus (KY785906). We compared the biological properties of the virus for example virus proliferation, virus elution, thermostability, and pH stability. Then, we evaluated the immune effects between rHA/NA-GD37 and GD37, which show that the recombinant avian influenza virus–inactivated vaccine can stimulate chickens to produce higher antibody titers and produce little inflammatory response after the challenge. It is noticeable that the recombinant virus-inactivated vaccine had better immune impact than the wild-type inactivated vaccine. Generally speaking, this study provides a new virus strain for the development of a H9N2 vaccine.

Dielectric elastomer generators (DEGs) provide a new solution for vibrational energy harvesting. Currently, a type of impact-based DEGs, which can harvest energy from ambient vibrations, has been proposed and studied through simulations. However, the energy conversion mechanism and the performance evaluation approach of such impact-based DEGs have not been fully studied yet, thus limiting the reliability of the research on the system design/optimization and performance evaluation. In this paper, a single-sided impact (SSI) model is proposed to reveal the impact-based energy conversion mechanism. Based on this model, a complete four-stage impact process is analyzed to reveal the energy conversion mechanism, and the electrical outputs and energy conversion efficiency are derived as the energy harvesting performance evaluation indexes. To use the developed analytical model to predict the system electrical response accurately, some important parameters including the coefficient of restitution (COR) and largest deflection of the membrane at impacts were obtained experimentally, and the system output voltages at impacts were measured to verify the theoretical approaches in calculating the system electrical outputs and studying the parameters' influences. Furthermore, the influences of the pre-stretched ratio, impact velocity, and input voltage on the system energy harvesting performance are studied through simulations. The research results can provide guidelines to improve the energy harvesting performance of the impact-based DEGs in real applications.

Abstract Background In the current surgical therapeutic regimen for the degenerative lumbar disease, both oblique lateral interbody fusion (OLIF) and lateral lumbar interbody fusion (LLIF) are gradually accepted. Thus, the objective of this study is to compare the radiographic and clinical outcomes of OLIF and LLIF for the degenerative lumbar disease. Methods We conducted an exhaustive literature search of MEDLINE, EMBASE, and the Cochrane Library to find the relevant studies about OLIF and LLIF for the degenerative lumbar disease. Random-effects model was performed to pool the outcomes about disc height (DH), fusion, operative blood loss, operative time, length of hospital stays, complications, visual analog scale (VAS), and Oswestry disability index (ODI). Results 56 studies were included in this study. The two groups of patients had similar changes in terms of DH, operative blood loss, operative time, hospital stay and the fusion rate (over 90%). The OLIF group showed slightly better VAS and ODI scores improvement. The incidence of perioperative complications of OLIF and LLIF was 26.7 and 27.8% respectively. Higher rates of nerve injury and psoas weakness (21.2%) were reported for LLIF, while higher rates of cage subsidence (5.1%), endplate damage (5.2%) and vascular injury (1.7%) were reported for OLIF. Conclusions The two groups are similar in terms of radiographic outcomes, operative blood loss, operative time and the length of hospital stay. The OLIF group shows advantages in VAS and ODI scores improvement. Though the incidence of perioperative complications of OLIF and LLIF is similar, the incidence of main complications is significantly different.

Cyclone separators, which have a high separation performance, play a crucial role in mitigating the occurrence of dust explosion incidents. This study aims to improve the performance of an axial cyclone separator using the results of simulations employing the RNG   k - ε model together with a user-defined function to simulate the wall collision process. The effectiveness of various structural modifications to the vortex tube has been addressed. Specifically, we found that increasing the number of blades, reducing the blade exit angle, and adopting L-shaped blades increase separation efficiency. Additionally, enlarging the guide vane and exhaust pipe diameters, as well as increasing the exhaust pipe inclination angle, contribute to an improved separation performance due to the developed tangential velocity and vortex cores. However, it also increases the pressure drop losses due to the increase in the turbulence pulsation entropy and the wall entropy, while the time-averaged entropy is found to be less significant. As a result, our study sheds light on the flow characteristics, the gas–solid separation process, and the energy loss mechanism in the cyclone separator. [ABSTRACT FROM AUTHOR]

Summary: Heading date (or flowering time) is a key agronomic trait that affects seasonal and regional adaption of rice cultivars. An unoptimized heading date can either not achieve a high yield or has a high risk of encountering abiotic stresses. There is a strong demand on the mild to moderate adjusting the heading date in breeding practice. Genome editing is a promising method which allows more precise and faster changing the heading date of rice. However, direct knock out of major genes involved in regulating heading date will not always achieve a new germplasm with expected heading date. It is still challenging to quantitatively adjust the heading date of elite cultivars with best adaption for broader region. In this study, we used a CRISPR‐Cas9 based genome editing strategy called high‐efficiency multiplex promoter‐targeting (HMP) to generate novel alleles at cis‐regulatory regions of three major heading date genes: Hd1, Ghd7 and DTH8. We achieved a series of germplasm with quantitative variations of heading date by editing promoter regions and adjusting the expression levels of these genes. We performed field trials to screen for the best adapted lines for different regions. We successfully expanded an elite cultivar Ningjing8 (NJ8) to a higher latitude region by selecting a line with a mild early heading phenotype that escaped from cold stress and achieved high yield potential. Our study demonstrates that HMP is a powerful tool for quantitatively regulating rice heading date and expanding elite cultivars to broader regions. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective cohort study. Objective: To investigate the effect of HRVA on the intrapedicular accuracy of C2PS placement through the freehand method in patients with BI and analyse the possible risk factors for C2PS malpositioning. Method: A total of 91 consecutive patients with BI who received 174 unilateral C2PS placements through the freehand method were retrospectively included. The unilateral pedicles were assigned to the HRVA and non-HRVA groups. The primary outcome was the intrapedicular accuracy of C2PS placement in accordance with the Gertzbein–Robbins scale. Moreover, the risk factors that possibly affected intrapedicular accuracy were assessed. Results: The rate of intrapedicular accuracy in C2PS placement in patients with BI was 23.6%. Results showed that the non-HRVA group had remarkably higher rates of optimal and clinically acceptable C2PS placement than the HRVA group. Nevertheless, the HRVA group exhibited similar results for grade B classification as the non-HRVA group. Moreover, in the HRVA and non-HRVA groups, the most common direction of screw deviations was the lateral direction. Furthermore, the multivariate analyses showed that the obliquity of the lateral atlantoaxial joint in the sagittal plane ≥15°, and that in the coronal plane ≥ 20°, isthmus height < 4.3 mm, and distance from the skin to the spinous process ≥ 2.8 cm independently contributed to a high rate of screw malpositioning in BI patients. Conclusion: The presence of HRVA in BI patients contributed to the high rate of malpositioning in C2PS placement via the freehand method. However, the rates of intrapedicular accuracy in patients with BI with and without HRVA were considerably low. [ABSTRACT FROM AUTHOR]