Continuous surveillance of enteroviruses (EVs) in urban domestic sewage can timely reflect the circulation of EVs in the environment and crowds, and play a predictive and early warning role in ...EV-related diseases. To better understand the long-term epidemiological trends of circulating EVs and EV-related diseases, we conducted a 9-year (2013 to 2021) surveillance study of non-polio EVs (NPEVs) in urban sewage in Guangzhou city, China. After concentrating and isolating the viruses from the sewage samples, NPEVs were detected and molecular typing was performed. Twenty-one different NPEV serotypes were identified. The most isolated EVs were echovirus 11 (E11), followed by coxsackievirus (CV) B5, E6, and CVB3. EV species B prevailed in sewage samples, but variations in the annual frequency of different serotypes were also observed in different seasons, due to spatial and temporal factors. E11 and E6 were detected continuously before 2017, and the number of isolates was relatively stable during the surveillance period. However, after their explosive growth in 2018 and 2019, their numbers suddenly decreased significantly. CVB3 and CVB5 had alternating trends; CVB5 was most frequently detected in 2013 to 2014 and 2017 to 2018, while CVB3 was most frequently detected in 2015 to 2016 and 2020 to 2021. Phylogenetic analysis showed that at least two different transmission chains of CVB3 and CVB5 were prevalent in Guangzhou City. Our results show that in the absence of a comprehensive and systematic EV-related disease surveillance system in China, environmental surveillance is a powerful and effective tool to strengthen and further investigate the invisible transmission of EVs in the population.
This study surveilled urban sewage samples from north China for 9 years to monitor enteroviruses. Samples were collected, processed, and viral identification and molecular typing were performed. We detected 21 different non-polio enteroviruses (NPEVs) with yearly variations in prevalence and peak seasons. In addition, this study is very important for understanding the epidemiology of EVs during the COVID-19 pandemic, as the detection frequency and serotypes of EVs in sewage changed considerably around 2020. We believe that our study makes a significant contribution to the literature because our results strongly suggest that environmental surveillance is an exceptionally important tool, which can be employed to detect and monitor organisms of public health concern, which would otherwise be missed and under-reported by case-based surveillance systems alone.
•Scientific questions: Expanding the Global Polio Eradication Initiative (GPEI) and establishing environmental surveillance systems in countries at risk of poliovirus transmission warrants the ...development of additional virus enrichment methods with reduced costs and shorter turnaround times.•Evidence before this study: The acute flaccid paralysis (AFP) case surveillance system is the gold standard for poliovirus surveillance; however, the “silent” transmission of poliovirus in the population makes environmental surveillance a crucial auxiliary tool for poliovirus surveillance.•New findings: The filtration method using a mixed cellulose ester (MCE) membrane is more sensitive than two-phase separation and can be used as a robust, sensitive, and cost-effective method to isolate enteroviruses from sewage.•Significance of the study: The filtration method using a mixed cellulose ester (MCE) membrane allows sensitive monitoring of the dynamic changes of enteroviruses in the environment. Additionally, this method enables researchers to track the actual dynamics of enterovirus transmission in human communities and provide early warnings for diseases in the population.
This study aimed to compare the sensitivity of two-phase separation and the filtration method using a mixed cellulose ester (MCE) membrane to detect enteroviruses in sewage samples. From December 2015 to July 2016, four domestic sewage samples (1 L/sample) were collected monthly from the Guangzhou Liede Sewage Treatment Plant, and each sewage sample was divided into two aliquots (500 mL). The sewage sample was concentrated using the two-phase separation and the filtration method using an MCE membrane, and the treated solutions were inoculated into cells for enterovirus isolation. Polymerase chain reaction amplification, VP1 sequencing, and enterovirus molecular typing were performed on the positive isolates. The detection rates of poliovirus (PV) and non-polio enterovirus (NPEV) obtained using the filtration method using an MCE membrane were higher than those using the two-phase separation method. McNemar's test showed that the detection rates of PV, NPEV, type 1 Sabin-like (SL1), type 2 Sabin-like (SL2), and type 3 Sabin-like (SL3) strain were not statistically significant (P > 0.05). In Guangdong Province, China, the detection rates for PV and NPEV were 53.13% and 62.50% (20/32), respectively. Twenty-seven PVs were isolated, three highly variable strains of the type 1 vaccine, with seven nucleotide substitutions in the VP1 region, compared with the type 1 Sabin strains. Eighty-seven strains of NPEV were isolated and nine serotypes were identified, among which coxsackievirus B3 (CVB3), echovirus 6(E6), and echovirus 11(E11) were the dominant strains. The filtration method using an MCE membrane is more sensitive than two-phase separation and can be used as a robust, sensitive, and cost-effective method to isolate enteroviruses from sewage.
The blind-hole method is the most widely used approach to experimentally determine the distribution of residual stress. This paper aims to improve test accuracy of welding residual stress and ...conducts an experimental study on the strain release factors involved when using the blind-hole method for Q235 and Q345, two steels commonly used in building structures. The ranges of strain release factors
A
and
B
in the elastic stage, the effects of strain release factors on residual stress calculated values, and the plastic corrected strain release factors are analyzed considering of the effect of plastic deformation around the blind hole on measurement accuracy. Finally, a simplified calculation formula to determine strain release factors is proposed for use with the blind-hole method. Results show that in the elastic stage, strain release factor
A
for Q235 and Q345 ranges from −0.399 to −0.525 and strain release factor
B
from −0.791 to −0.960. Changing the strain release factors
A
and
B
shows that calculated residual tensile stress varies in relation to a decrease in both factor values. However, there is a increase in calculated residual compressive stress with a decrease in the strain release factor
A
value, but there is an decrease with a decrease in strain release factor
B
value. Calculated residual stress applied to elastic strain release factors is compared with that applied to amended plastic strain release factors for Q235 steel. The maximum deviation between calculated residual stress and test stress is reduced from 21.1 to 1.0%, and for Q345 steel from 26.5 to 1.2%. It is thus evident that the plastic correction formula proposed in this paper can be used in calculations when conducting a residual stress test.
Sex chromosomes evolved from autosomes many times across the eukaryote phylogeny. Several models have been proposed to explain this transition, some involving male and female sterility mutations ...linked in a region of suppressed recombination between X and Y (or Z/W, U/V) chromosomes. Comparative and experimental analysis of a reference genome assembly for a double haploid YY male garden asparagus (Asparagus officinalis L.) individual implicates separate but linked genes as responsible for sex determination. Dioecy has evolved recently within Asparagus and sex chromosomes are cytogenetically identical with the Y, harboring a megabase segment that is missing from the X. We show that deletion of this entire region results in a male-to-female conversion, whereas loss of a single suppressor of female development drives male-to-hermaphrodite conversion. A single copy anther-specific gene with a male sterile Arabidopsis knockout phenotype is also in the Y-specific region, supporting a two-gene model for sex chromosome evolution.
Over the last two decades, Geiger-mode lidar (GML) systems have been developing rapidly in defense and commercial applications, demonstrating high point density and great collection efficiency. We ...presented a circular scanning GML system simulation model for performance prediction and developed a GML system for civilian mapping. The lidar system used an eye-safe fiber laser at 1545 nm coupled with a 64 × 64 pixels photon-counting detector array. A real-time data compression algorithm was implanted to reduce half of the data transmission rate and storage space compared to the uncompressing situation. The GML system can operate at aircraft above-ground levels (AGLs) between 0.35 km and 3 km, and at speeds in excess of 220 km/h. The initial flight tests indicate that the GML system can operate day and night with an area coverage of 366 km
/h. The standard deviations of the relative altimetric accuracy and the relative planimetric accuracy are 0.131 m and 0.152 m, respectively. The findings presented in this article guide the implementation of designing an airborne GML system and the data compression method.
In this article we study the solution
u
(
t
,
x
) of the Cauchy problem of linear damped wave equation. We obtain the sufficient and necessary condition of the boundedness of the solution
u
(
t
,
x
...) on the Triebel–Lizorkin space at a fixed time
t
.
We previously reported that the
virulence protein VirD5 possesses transcriptional activation activity, binds to a specific DNA element D5RE, and is required for
-mediated stable transformation, but ...not for transient transformation. However, direct evidence for a role of VirD5 in plant transcriptional regulation has been lacking. In this study, we found that the Arabidopsis gene
(coding for VirD5 response F-box protein,
) is regulated by VirD5.
has two alternative transcripts of 930 bp and 1594 bp that encode F-box proteins of 309 and 449 amino acids, designated as D5RF.1 and D5RF.2, respectively. D5RF.2 has a N-terminal extension of 140 amino acids compared to D5RF.1, and both of them are located in the plant cell nucleus. The promoter of the
contains two D5RE elements and can be activated by VirD5. The expression of D5RF is downregulated when the host plant is infected with
deleted
. Similar to VirD5, D5RF also affects the stable but not transient transformation efficiency of
. Some pathogen-responsive genes are downregulated in the
mutant. In conclusion, this study further confirmed
VirD5 as the plant transcription activator and identified
as the first target gene of VirD5 in regulation.
During Agrobacterium (Agrobacterium tumefaciens) infection, the translocated virulence proteins (VirD2, VirE2, VirE3, VirF and VirD5) play crucial roles. It is thought that, through protein–protein ...interactions, Agrobacterium uses and abuses host plant factors and systems to facilitate its infection. Although some molecular functions have been revealed, the roles of VirD5 still need to be further elucidated.
Here, plant transformation and tumorigenesis mediated by genetically modified Agrobacterium strains were performed to examine VirD5 roles. In addition, protein–protein interaction-associated molecular and biochemistry technologies were used to reveal and elucidate VirD5 interaction with Arabidopsis VirE2 interacting protein 2 (VIP2).
Our results showed that deleting virD5 from Agrobacterium reduced its tumor formation ability and stable transformation efficiency but did not affect the transient transformation efficiency. We also found that VirD5 can interact with Arabidopsis VIP2. Further experiments demonstrated that VirD5 can affect VIP2 binding to cap-binding proteins (CBP20 and CBP80). The tumorigenesis efficiency for cbp80 mutant was not significantly changed, but that for cbp20, cbp20cbp80 mutants were significantly increased.
This work demonstrates experimentally that VirD5 is required for efficient Agrobacterium infection and may promote this process by competitive interaction with Arabidopsis VIP2. CBP20 is involved in the Agrobacterium infection process and its effect can be synergistically enhanced by CBP80.
This article proposes a line scanning chromatic confocal sensor to solve the problem of limited chromatic confocal measurement due to the small measurement range and low measurement efficiency in the ...industrial inspection process. To obtain an extensive dispersion range, the advantages of a simple single-axis structure are combined with the advantages of a large luminous flux of a biaxial structure. Considering large-scale measurement, our sensor uses off-axis rays to limit the illumination path and imaging path to the same optical path structure. At the same time, the field of view is expanded, and a symmetrical structure is adopted to provide a compact optical path and improve space utilization. The simulation and physical system test results shows that the sensor scanning line length is 12.5 mm, and the axial measurement range in the 450 nm to 750 nm band is better than 20 mm. The axial resolution of the detector is ±1 µm combined with the subpixel centroid extraction data processing method, and the maximum allowable tilt angle for specular reflection samples is ±7°. The thicknesses of transparent standard flat glass and the wet collagen membrane are measured. The maximum average error is 1.3 µm, and the relative error is within 0.7%. The constructed sensor is of great significance for rapidly measuring the three-dimensional profile, flatness, and thickness in the fields of transparent biological samples, optics, micromechanics, and semiconductors.
The corneal epithelium, located as the outermost layer of the cornea, is inherently susceptible to injuries that may lead to corneal opacities and compromise visual acuity. Rapid restoration of ...corneal epithelial injury is crucial for maintaining the transparency and integrity of the cornea. Cell spray treatment emerges as an innovative and effective approach in the field of regenerative medicine. In our study, a cell spray printing platform was established, and the optimal printing parameters were determined to be a printing air pressure of 5 PSI (34.47 kPa) and a liquid flow rate of 30 ml/h. Under these conditions, the viability and phenotype of spray-printed corneal epithelial cells were preserved. Moreover, Lycium barbarum glycopeptide (LBGP), a glycoprotein purified from wolfberry, enhanced proliferation while simultaneously inhibiting apoptosis of the spray-printed corneal epithelial cells. We found that the combination of cell spray printing and LBGP facilitated the rapid construction of multilayered cell sheets on flat and curved collagen membranes in vitro. Furthermore, the combined cell spray printing and LBGP accelerated the recovery of the rat corneal epithelium in the mechanical injury model. Our findings offer a therapeutic avenue for addressing corneal epithelial injuries and regeneration.
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•Cell spray preserves the activity and phenotype of corneal epithelial cells.•Cell spray combined with LBGP enables rapid formation of corneal epithelial cell sheets.•Cell spray combined with LBGP accelerates rat corneal epithelium recovery after mechanical injury.
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