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Abstract The genus Flavivirus comprises numerous emerging and re‐emerging arboviruses causing human illness. Vaccines are the best approach to prevent flavivirus diseases. But pathogen diversities are always one of the major hindrances for timely development of new vaccines when confronting unpredicted flavivirus outbreaks. We used West Nile virus (WNV) as a model to develop a new live‐attenuated vaccine (LAV), WNV‐poly(A), by replacing 5ʹ portion (corresponding to SL and DB domains in WNV) of 3ʹ‐UTR with internal poly(A) tract. WNV‐poly(A) not only propagated efficiently in Vero cells, but also was highly attenuated in mouse model. A single‐dose vaccination elicited robust and long‐lasting immune responses, conferring full protection against WNV challenge. Such “poly(A)” vaccine strategy may be promising for wide application in the development of flavivirus LAVs because of its general target regions in flaviviruses.

Purpose Vesicovaginal fstulae (VVF) have a signifcant negative impact on quality of life, with failed surgical repair resulting in ongoing morbidity. Our aim was to characterize the rate of VVF repair and repair failures over time, and to identify predictors of repair failure. Methods We completed a population-based, retrospective cohort study of all women who underwent VVF repair in Ontario, Canada, aged 18 and older between 2005 and 2018. Risk factors for repair failure were identifed using multivariable cox proportional hazard analysis; interrupted time series analysis was used to determine change in VVF repair rate over time. Results 814 patients underwent VVF repair. Of these, 117 required a second repair (14%). Mean age at surgery was 52 years (SD 15). Most patients had undergone prior gynecological surgery (68%), and 76% were due to iatrogenic injury. Most repairs were performed by urologists (60%). Predictors of VVF re-repair included iatrogenic injury etiology (HR 2.1, 95% CI 1.3–3.45, p=0.009), and endoscopic repair (HR 6.1, 95% CI 3.1–11.1, p<0.05,); protective factors included combined intra-abdominal/trans-vaginal repair (HR 0.51, 95% CI 0.3–0.8, p=0.009), and surgeon years in practice (21+years—HR 0.5, 95% CI 0.3–0.9, p=0.005). Age adjusted annual rate of VVF repair (ranging from 0.8 to 1.58 per 100,000 women) and re-repair did not change over time. Conclusions VVF repair and re-repair rates remained constant between 2005 and 2018. Iatrogenic injury and endoscopic repair predicted repair failure; combined intra-abdominal/trans-vaginal repair, and surgeon years in practice were protective. This suggests surgeon experience may protect against VVF repair failure. [ABSTRACT FROM AUTHOR]

To explore the signal transmission mechanism of the arbuscular mycorrhizal network against root rot of Salvia miltiorrhiza. In this experiment, the arbuscular mycorrhizal hyphal network was established among Salvia miltiorrhiza plants, and a two plant three-compartment culture model was established. The root of the donor Salvia miltiorrhiza was inoculated with the pathogenic fungi Fusarium solani. The changes of hormone signals such as jasmonic acid and salicylic acid and the expression of related defense genes in the recipient Salvia miltiorrhiza plants in different periods were measured, to study the underground disease resistance signal transmission mechanism among medicinal plants. Salvia miltiorrhiza can transmit the signal of resistance to root rot through the jasmonic acid pathway; When plants suffer from disease stress, the content of JA increases significantly, and the increase of JA content will inhibit the content of SA in plants; The gene expression of PR-10 gene in the roots of Salvia miltiorrhiza with arbuscular mycorrhizal network infected by pathogenic fungi was 17.56 times higher than that inoculated only with pathogenic fungi; Changes in hormone content will also cause changes in the expression of related defense genes, such as SnRK2 is inhibited by ABA in the signal transduction pathway, while JA and ABA show antagonistic changes after inoculation of pathogenic fungi in Salvia miltiorrhiza, so JA may positively regulate the expression of SnRK2 gene. Plants can transmit signals through AM hyphal network after being stressed by the pathogen Fusarium solani. In the arbuscular mycorrhizal hyphal network, JA has important significance for the signal transmission of resistance to root rot and disease resistance of Salvia miltiorrhiza, which can make Salvia miltiorrhiza ready for stress resistance and improve the stress resistance of Salvia miltiorrhiza. This experiment is of great significance to further analyze the signal transmission mechanism of the arbuscular mycorrhizal hyphal network. [ABSTRACT FROM AUTHOR]

To overcome the disadvantages of inhomogeneous microstructures and poor mechanical properties of additively manufactured Ti-6Al-4V alloys, a novel technique of hybrid deposition and synchronous micro-rolling is proposed. The micro-rolling leads to equiaxed prior β grains, thin discontinuous intergranular a, and equiaxed primary α, in contrast to the coarse columnar prior β grains without the application of micro-rolling. The recrystallization by micro-rolling results in discontinuous intergranular α via the mechanism of strain and interface-induced grain boundary migration. The evolution of α globularization, driven by a solute concentration gradient, starts from the sub-boundary until the formation of equiaxed primary α. Simultaneous strengthening and toughening are achieved, which means an increase in yield strength, ultimate tensile strength, fracture elongation, and work hardening rate. The formation of α recrystallization leads to more fine grain boundaries to strengthen the yield strength, and the improvement of ductility is due to the better-coordinated deformation ability of discontinuous intergranular α and equiaxed primary α. As a result, the fracture mode in micro-rolling changes from intergranular type to transgranular type. [ABSTRACT FROM AUTHOR]

Nanolubricants are dispersed nano-scales solid particles in a base fluid. Due to high demand for higher efficiency in thermal application systems, nanolubricants is an ideal option to meet the particular demand. As the result a numerous scientist have been investigating to replace the base fluid in the vapor compression refrigeration (VCR) system with nanolubricants. This paper elaborates the major factors that influence the VCR system performance mechanism through thermal conductivity enhancement, solubility and homogenous solution, stability, viscosity and tribological improvement of nanolubricants, respectively. The two common methods in preparing nanolubricants are one-step and two-step method which have been discussed in this paper. The current development of nanolubricants and hybrid nanolubricants have been elaborated. The findings show that the viscosity and thermal conductivity escalated with the improved of nanolubricants volume concentration. The studies revealed that introducing nanoparticles into lubricant has a major effect in improving viscosity, thermal conductivity and tribological improvement that led to the improvement of heat transfer enhancement mechanism. [ABSTRACT FROM AUTHOR]

Vitellogenin (Vg) is an important factor that impacts oocyte maturation, egg formation and embryonic development in Arthropoda. Two orthologs of Vg gene were obtained from the genome of Phytoseiulus persimilis and termed as PpVg1 and PpVg2. Both orthologs belong to the large lipid transfer protein superfamily. The expression of PpVg1 and PpVg2 was low in immatures and male adults, and increased rapidly in female adults after mating, and reached a peak before the first egg was laid (168× and 20.5× the level in virgin females, respectively). When PpVg1 and PpVg2 were interfered with dsRNA, the relative expression decreased by 81.0 and 30.9%, respectively, and 7.8 and 31.4% interfered individuals died within 24 h. Among surviving individuals, ca. 51.1 and 44.8% are infertile. Factors that might be related to expression of Vg genes are also discussed. [ABSTRACT FROM AUTHOR]

Purpose: The effect of paraspinal muscles atrophy and fat infiltration (FI) on the complications of spinal surgery has not been established. Methods: A review of the literature was conducted from a search of the PubMed, EMBASE, and Web of Science databases from inception through January 2021. The literature was searched and assessed by independent reviewers based on criteria that included an assessment of preoperative paraspinal muscle morphology in addition to measuring its relationship to surgical complications. All relevant papers were assessed for risk of bias according to the modified Newcastle Ottawa Scale and the Joanna Briggs Institute Critical Appraisal Tools. A narrative synthesis was conducted. Results: The initial search yielded 5632 studies, of which 16 studies were included in the analysis. All included studies were at a low risk of bias. There existed strong evidence that the atrophy and FI of paraspinal muscles had an association with the development of bone nonunion (two high quality studies), pedicle screw loosening (two high quality studies), adjacent segment degeneration (three high quality studies) and proximal junctional kyphosis (five high quality studies) after lumbar surgery. Besides, there is also limited evidence for association between atrophy and FI of paraspinal extensor muscles and less local and global curve improvement. Conclusions: Strong evidence was found for an association between preoperative paraspinal muscle degeneration and multiple postoperative complications after lumbar surgery. However, the findings should be interpreted with caution due to the small quantity of the available literature and high heterogeneity among studies. [ABSTRACT FROM AUTHOR]

This study combined theoretical analysis, numerical simulation via FLAC3D software, innovative design, and field measurements for establishing the mechanical model of the stressed coal rock and deriving the deformation and failure characteristics of the roadway in a steep coal seam. The No. 49# steep-seam working face of the Xintie Coal Mine, China, was used as a case study with asymmetrical force characteristics of the mining roadway. The roof and the right side of the roadway under study were identified as the main deformation and failure zones in the roadway of the steep working face. Next, a rigid/flexible support method that fully enclosed two sides and the roof was designed and substantiated. It comprised three pre-stressed resin anchor cables combined with anchor rods, iron net, and steel bands for the roadway roof support; besides, three anchor rods were combined with iron net and steel bands for supporting the right side of the roadway. A novel self-mobile forepoling hydraulic support group with side and roof support functions was developed. A grouting reinforcement was applied to the crushed coal rock in the geologic anomaly zone to enhance the overall performance. Finally, the measured displacements of the roof and the floor were found to exceed those of the roadway sides. The whole advancing process of the steep-seam working face was conditionally split into three segments, namely, Segment I with no mining effect (at a distance over 50 m from the working face), Segment II with a mining effect (at 20 ~ 50 m from the working face), and Segment III with a strong mining effect (20 m in front of the working face). The displacement at the deepest point on the roof was the maximal, followed by that in the range of 0 ~ 1.5 m, which made it possible to reduce the number of anchors on the left side of the roadway required by the conventional symmetric support mode. The performed field measurements proved that the proposed asymmetric support mode ensured the mining safety requirements of the working face under normal mining operations, being more cost-effective and efficient than the conventional symmetric one. [ABSTRACT FROM AUTHOR]