Sequencing on an imported case in China of COVID-19 Delta variant emerging from India in a cargo ship in Zhoushan, China.

A cluster of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections was found in a cargo ship under repair in Zhoushan, China. Twelve of 20 crew members were identified as SARS-CoV-2 positive. We analyzed four sequences and identified them all in the Delta branch emerging from India with 7-8 amino acid mutation sites in the spike protein.

Potential Presymptomatic Transmission of SARS-CoV-2, Zhejiang Province, China, 2020.

We report a 2-family cluster of persons infected with severe acute respiratory syndrome coronavirus 2 in the city of Zhoushan, Zhejiang Province, China, during January 2020. The infections resulted from contact with an infected but potentially presymptomatic traveler from the city of Wuhan in Hubei Province.

Detection of Novel Coronavirus by RT-PCR in Stool Specimen from Asymptomatic Child, China.

We report an asymptomatic child who was positive for a coronavirus by reverse transcription PCR in a stool specimen 17 days after the last virus exposure. The child was virus positive in stool specimens for at least an additional 9 days. Respiratory tract specimens were negative by reverse transcription PCR.

Molecular evolution of GII.P17-GII.17 norovirus associated with sporadic acute gastroenteritis cases during 2013-2018 in Zhoushan Islands, China.

In this study, we investigated the molecular characteristics and spatio-temporal dynamics of GII.P17-GII.17 norovirus in Zhoushan Islands during 2013-2018. We collected 1849 samples from sporadic acute gastroenteritis patients between January 2013 and August 2018 in Zhoushan Islands, China. Among the 1849 samples, 134 (7.24%) samples were positive for human norovirus (HuNoV). The complete sequence of GII.17 VP1 gene was amplified from 31 HuNoV-positive samples and sequenced. A phylogenetic tree was constructed based on the full-length sequence of the VP1 gene. Phylogenetic analysis revealed that the GII.17 genotype detected during 2014-2018 belongs to the new GII.17 Kawasaki variant. Divergence analysis revealed that the time of the most recent common ancestor (TMRCA) of GII.17 in Zhoushan Islands was estimated to be between 1997 and 1998. The evolutionary rate of the VP1 gene of the GII.17 genotype norovirus was 1.14 × 10-3 (95% HPD: 0.62-1.73 × 10-3) nucleotide substitutions/site/year. The spatio-temporal diffusion analysis of the GII.17 genotype identified Hong Kong as the epicenter for GII.17 dissemination. The VP1 gene sequence of Zhoushan Island isolates correlated with that of Hong Kong and Japan isolates.

Upscale production of ethyl (S)-4-chloro-3-hydroxybutanoate by using carbonyl reductase coupled with glucose dehydrogenase in aqueous-organic solvent system.

(S)-4-chloro-3-hydroxybutanoate ((S)-CHBE) is an important chiral intermediate to synthesize the side chain of cholesterol-lowering drug atorvastatin. To biosynthesize the (S)-CHBE, a recombinant Escherichia coli harboring the carbonyl reductase and glucose dehydrogenase was successfully constructed. The recombinant E. coli was cultured in a 500-L fermentor; after induction and expression, the enzyme activity and cell biomass were increased to 23,661.65 U/L and 13.90 g DCW/L which was 3.24 and 2.60-folds compared with those in the 50 L fermentor. The biocatalytic process for the synthesis of (S)-CHBE in an aqueous-organic solvent system was constructed and optimized with a substrate fed-batch strategy. The ethyl 4-chloro-3-oxobutanoate concentration reached to 1.7 M, and the (S)-CHBE with yield of 97.2 % and enantiomeric excess (e.e.) of 99 % was obtained after 4-h reaction in a 50-L reactor. In this study, the space-time yield and space-time yield per gram of biomass (dry cell weight, DCW) were 413.17 mM/h and 27.55 mM/h/g DCW for (S)-CHBE production, respectively, which were the highest values as compared to previous reports. Finally, (S)-CHBE was extracted from the reaction mixture with 82 % of yield and 95 % of purity. This study paved the foundation for the upscale production of (S)-CHBE by biocatalysis method.

Seroprevalence of coxsackievirus A16 antibody among people of various age groups: a systematic review and meta-analysis.

BACKGROUND: Coxsackie virus group A type 16 (CoxA16) is the main pathogen and usually an alternative to or joins in prevalence with enterovirus 71 (EV71) causing hand, foot and mouth disease (HFMD). The objective of this study was to estimate the seroprevalence of CoxA16 antibody among people of various age groups by a systematic review and meta-analysis. METHODS: The literature of seroprevalence of CoxA16 antibody among people has been systematically searched through databases from the date of their establishment to Jan. 2021. Estimates of seroprevalence of CoxA16 antibody by gender and age groups have been summarized by using fixed- and random- effect models. All analyses have been conducted in STATA version 12.0 software. RESULTS: A total of 14 publications with 9 in English and 5 in Chinese containing 9562 samples were finally included in the meta-analysis. The seroprevalence of CoxA16 antibody reported in different studies range from 24.85 to 76.92 %. Meta-analysis has revealed that the seroprevalence of CoxA16 antibody was 56.3 % (95 %CI: 47.7 %~64.9 %) in the overall population and 55.1 % (95 %CI: 44.1 %~66.1 %) in the Chinese population. Subgroup analysis by gender has revealed that the seroprevalence of CoxA16 antibody was 56.1 % (95 %CI: 45.2 %~67.1 %) in males and 60.0 % (95 %CI: 50.0 %~69.9 %) in females. Subgroup analysis by age groups has revealed that the seroprevalence of CoxA16 antibody was 49.1 % (95 %CI: 36.2 %~62.0 %) in the 0 ~ 5 age group and 63.9 % (95 %CI: 53.1 %~74.7 %) in the over 5 age group. Begg's funnel plots have suggested that there were no publication bias in all groups. Sensitive analysis has suggested that the result of the meta-analysis was stable. CONCLUSIONS: The seroprevalence of CoxA16 antibody was closely related to age. Children under 5 years old were the main susceptible groups for CoxA16 and also the key groups for the prevention and control of HFMD.

Association Between the Ambient Fine Particulate Pollution and the Daily Internal Medicine Outpatient Visits in Zhoushan, China: A Time-Series Study.

Background: There has been a recent worsening of air pollution in China, which poses a huge threat to public health by inducing and promoting circulatory and respiratory diseases. This study aimed to explore the association between the concentration of air pollution and daily internal medicine outpatient visits registered for the treatment of circulatory and respiratory symptoms in Zhoushan, China using a time-series method. Methods: We validated and acquired the daily internal medicine outpatient visits records between January 1, 2014, and December 31, 2019, from the Zhoushan Center for Disease Control and Prevention in Zhejiang, China. Further, we collected the daily average records of the ambient air pollutants from the Zhoushan Environmental Monitoring Centre within the same duration. A generalized additive model with the natural splines was constructed to explore the association between the ambient air pollutants and daily internal medicine outpatient visits. Further, we conducted a lag analysis by using the distributed lag non-linear model to estimate the time-delayed effects of the air pollutants on the daily internal medicine outpatient visits. Results: A total of 2,190,258 daily internal medicine outpatient visits with a mean of 202.4 visits per day were recorded. The non-linear relationships were found among particulate matter2.5 (PM2.5), sulfur dioxide (SO2), and the daily internal medicine outpatient visits. Overall, PM2.5 was positively correlated with the daily internal medicine outpatient visits. Both ozone (O3) and SO2 had significant delayed effects on the daily internal medical outpatient numbers; however, PM2.5 only showed a short-term risk. Conclusion: Short-term exposure to PM2.5 was associated with an increase in the daily internal medicine outpatient visits for circulatory and respiratory diseases/symptoms in Zhoushan, China. SO2 and O3 were shown to induce significant effects after a concentration-dependent time lag.

Investigation of Damage Reduction When Dry-Drilling Aramid Fiber-Reinforced Plastics Based on a Three-Point Step Drill.

Aramid fiber-reinforced plastic (AFRP) is widely used in bullet-proof and armor structures, and is difficult to drill because of the high-toughness aramid fibers with ductile fracturing-differently from carbon fiber. Therefore, drilling quality cannot be ensured by the drilling used for carbon fiber-reinforced plastic, and frequently, delamination and burrs occur in the drilling process. This article first established a two-dimensional cutting model for analyzing the fiber deformation and material interface cracking. According to the model, reducing the thrust force and the radial force of the edge on the fibers is an effective way to reduce the fiber deformation, and a three-point step drill is proposed further. Comparative experiments were carried out among twist drilling, candle core drilling and three-point step drilling under three drilling parameters. The results show that the three-point step drill changed the traditional cutting behavior on the drill-exit material into a compound process. Finally, the AFRP was cut effectively with the novel drill with a small thrust force, and the delamination and "burrs area" were reduced through different drilling parameters. In summary, the three-point step drill can drill the AFRP without delamination and burrs with 0.02 mm/rev, which provides a new solution of cost-effective production for AFRP manufacturers.

Transmission of COVID-19 in the terminal stages of the incubation period: A familial cluster.

We report a familial cluster of 2019 novel coronavirus disease (COVID-19) to assess its potential transmission during the incubation period. The first patient in this familial cluster was identified during the presymptomatic period, as a close contact of a confirmed patient. Five family members had close contact with this first patient during his incubation period, with four of them confirmed positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the subsequent sampling tests.

[Study on synthesis, structure characterization and fluorescence of europium complexes of 2-(4-fluorobenzoyl) benzoic acid].

The present paper reports three new europium complexes, EuL3(H2O)6, EuL3Phen(H2O)4 and EuL3 (TPPO) (H2O)5, synthesized with Eu(NO3)3 x 6H2O, 2-(4-fluorobenzoyl) benzoic acid, Phen and TPPO(L = 2-(4-fluorobenzoyl) benzoic acid, Phen = 1, 10-phenanthroline, TPPO = triphenyl phosphine oxide). Their composition and chemical structures were characterized by elemental analysis, IR and 1H NMR spectroscopy. The IR spectra indicated that all complexes exhibited the characteristic peaks of carboxylate, asymmetric stretching vibration (vas (CO2(- and symmetric stretching vibration (vs (CO2(- peaks; the C = O stretching band at 1,692 cm(-1) of COOH and the O--H stretching band around 2,500-3,200 cm(-1) disappeared. All these complexes had a smaller Deltav(vas (CO2(-))-vs(CO2(- value than that of NaL, so the carboxylate groups coordinated with the europium ion in the form of bridging bidentate. In 1HNMR, the signals of hydrogen in 2-(4-fluorobenzoyl) benzoic acid became wide and shifted upfield, and those in Phen, TPPO shifted downfield. The excitation and emission spectra were recorded at room temperature. The excitation spectra showed that the optimum excitation peaks of these three complexes, EuL3 (H2O)6, EuL3Phen(H2O)5 and EuL3(TPPO)(H2O)5, were at 353.0, 355.0 and 357.0 nm, respectively. All these three complexes showed Eu3+ ion characteristic emission bands, the electron-dipole transition 5D0 --> 7F2 and magnetism dipole transition 5D0 --> 7F1; their emission peaks were at 596.0, 617.0; 596.0, 619.0; 595.0, 620.0 nm, and the relative intensities were 1.1, 8.6; 15.2, 100.0; 3.6, 23.2, respectively. The intensity of 5D0 --> 7F2 was stronger than that of 5D0 --> F1, which indicated that europium ions were at asymmetric center. The emission intensities of europium ions were greatly sensitized by Phen.

[Study on photoluminescence of 2-(4-chloro-benzoyl)benzoic acid complexes].

Eight complexes of europium and terbium were synthesized, with 2-(4-chloro-benzoyl)benzoic acid as an essential ligand and other three distinct ligands, including 1, 10-phenanthroline, triphenylphosphine oxide and diphenyl sulfoxide, as selective ligands. They were Eu(CBBA)3 (H2O)4, Eu(CBBA)3 (Phen) (H2O)6, Eu(CBBA)3 (TPPO) (H2O)4, Eu(CBBA)3 (DPSO) (H2O)5, Tb(CBBA)3 (H2O)4, Tb(CBBA)3 (Phen)(H2O)3, Tb(CBBA)3(TPPO)(H2O)2 and Tb(CBBA)3 (DPSO)(H2O)4, respectively. Then their excitation and emission spectra were measured, and that how the central ions were differently impacted by the three second ligands was also compared. It was easily to be seen that from the spectra all the complexes luminesced with the similar special peaks. However, the luminescence intensity was evidently distinct, because 1, 10-phenanthroline, triphenylphosphine oxide and diphenyl sulfoxide were coordinated with them, and exerted different effects on transferring energy to the central ions. In the complexes of europium, Eu(CBBA) (Phen) (H2O) 6 and Eu(CBBA) (DPSO) (H2O) 5 each luminesced more strongly than Eu(CBBA)3 (H2O)4, however, Eu(CBBA)3(TPPO) (H2O)4 luminesced more weakly than Eu(CBBA)3 (H2O)4. Moreover, Eu(CBBA) (DPSO)(H2O)5 luminesced more intensely than Eu(CBBA)3 (Phen)(H2O)6. So 1,10-phenanthroline and diphenyl sulfoxide could sensitize the luminescence, whereas triphenylphosphine oxide could quench the luminescence in the certain Eu complexes. In Tb complexes, diphenyl sulfoxide sensitized the luminescence of Tb(CBBA)3 (DPSO)(H2O)4, and reversely, 1,10-phenanthroline and triphenylphosphine oxide quenched differently the luminescence of Tb(CBBA)3 (Phen)(H2O)3 and Tb(CBBA) (TPPO)(H2O)2. 1,10-phenanthroline quenched more strongly than triphenylphosphine. From IR spectra, the structure of the complexes was conjectured approximately. In the region of 3 200-3 600 cm(-1), there were some weak vibrant peaks owed to hydroxyl of water, a good proof that there were water molecules in the complexes themselves.

Animals as amplification hosts in the spread of severe fever with thrombocytopenia syndrome virus: A systematic review and meta-analysis.

OBJECTIVES: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne infectious disease caused by severe fever with thrombocytopenia syndrome virus (SFTSV). The seroprevalence of anti-SFTSV antibodies specific to SFTSV (IgG or IgM) has been investigated in different animal hosts in many epidemiological studies, but no systematic estimation of seroprevalence has yet been performed. Hence, this meta-analysis was conducted in order to obtain a more comprehensive result to clarify the prevalence of SFTSV in animals. METHODS: A search for all relevant articles was conducted in the major national and international electronic databases up to August 2018. Data on seroprevalence of SFTSV antibodies (IgM and IgG) were extracted as the primary outcome. The pooled seroprevalence rates and 95% confidence intervals (95% CI) were determined. RESULTS: Overall, anti-SFTSV antibodies (IgG or IgM) were detected in 15 animal species. The pooled seroprevalence of anti-SFTSV antibodies was 45.70% in goats and sheep, 36.70% in cattle, 29.50% in dogs, 9.60% in chickens, 3.20% in rodents, and 3.20% in pigs. The seroprevalence of SFTSV in animals that had a confined range was significantly lower than that in free-range animals. SFTSV RNA was detected in 11 animal species, with a carriage rate varying from 0.23% to 26.31%. CONCLUSIONS: SFTSV has a wide spectrum of animal hosts, including domestic and wild animals. The prevalence of SFTSV is high among specific animal species.

Molecular epidemiology and spatiotemporal dynamics of norovirus associated with sporadic acute gastroenteritis during 2013-2017, Zhoushan Islands, China.

A total of 1 590 fecal swabs and stool samples from sporadic acute gastroenteritis patients of all ages were collected from January 2013 to March 2018 in the Zhoushan Islands, China, with 99 (6.23%) samples subsequently identified as human norovirus (HuNoV) positive. Phylogenetic analysis of partial RdRp and VP1 gene regions identified 10 genotypes of the GII genogroup and 3 genotypes of the GI genogroup. The predominant genotype was GII.P17-GII.17 (42.86%, 33/77), followed by GII.Pe-GII.4_Sydney 2012 (24.68%, 19/77) and GII.P16-GII.2 (12.96%, 10/77). However, the prevailing genotype in the Zhoushan Islands has shifted on three separate occasions. The GII.Pe-GII.4_Sydney_2012 strain was dominant in 2013-2014, the GII.P17-17 strain was dominant in 2015-2016, and the GII.P16-GII.2 strain was dominant in 2017. Divergence analysis showed that the re-emerging GII.P16-GII.2 strains clustered with the Japanese 2010-2012 GII.P16-GII.2 strains, and the time of the most recent common ancestor was estimated to have occurred in 2012 to 2013. The evolutionary rates of the RdRp gene region of the GII.P16 genotype and the VP1 gene region of the GII.2 genotype were 2.64 × 10(-3) (95% HPD interval, 2.17-3.08 × 10(-3)) and 3.36 × 10(-3) (95% HPD interval, 2.66-4.04 × 10(-3)) substitutions/site/year, respectively. The migration pattern of the HuNoV GII.2 genotype in China demonstrated that the re-emerging GII.P16-GII.2 strains were first introduced into Hong Kong from Japan, and then spread from Hong Kong to other coastal areas. Our results also showed that the GII.P16-GII.2 strains in the Zhoushan Islands were likely introduced from Jiangsu Province, China, in 2016.

[Influence of inert nuclei (La3+, Y3+ and Gd3+) on fluorescence of europium complex with phenylglyoxylic acid and phenathroline].

Three series of dinuclear complexes (Eux RE(1-x) L3 phen) of phenylglyoxylic acid and phenathroline with different molar ratios of Eu3+ to inert nuclei (RE = La3+, Y3+ and Gd3+) were synthesized. Their excitation and emission spectra were studied. The excitation spectra showed that the optimum excitation wavelengths of the complexes are all in the range of 350-360 nm, which belong to the excitation peaks of ligands, and the weak excitation peak of Eu3+ is at about 398 nm; The emission spectra showed that there are five emission bands at about 583, 595, 617, 654 and 703 nm respectively for all the complexes, due to (5)D0 - (7)F0, (5)D0 - (7)F1, (5)D0 - (7)F2, (5)D0 - (7)F3 and (5)D0 - (7)F4 transitions of Eu3+ respectively. The authors also found that the emission peak positions of Eu3+ shift the most in the complexes Eu(x) La(1-x) L3 phen, the position of (5)D0 - (7)F2 transition shifts 5.2 nm when the molar ratio of Eu3+:La3+ is 0.3: 0.7, but the addition of Y3+ and Gd3+ makes the emission peak positions of Eu3+ change less than that of La3+. Meanwhile the luminescence intensity of Eu3+ can be most enhanced by La3+ in all the complexes. The conclusion we found in the present paper could help search the luminescence materials with low cost and good luminescence properties.

Seroprevalence of severe fever with thrombocytopenia syndrome virus in China: A systematic review and meta-analysis.

OBJECTIVE: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by a novel bunyavirus-SFTSV. The seroprevalence of anti-SFTSV antibodies including immunoglobulin G (IgG) and immunoglobulin M (IgM), specific to SFTSV in the general population has been investigated in various epidemiological studies with inconsistent results. Here, we clarify this discrepancy and reach a more comprehensive result by mean of a meta-analysis. METHODS: All relevant articles were searched in the electronic databases (PubMed, Web of science, Embase, Chinese National Knowledge Infrastructure database, Chinese Wanfang database) up to November 2016. The pooled seroprevalence and 95% confidence intervals (95% CIs) were calculated by random- or fixed- model on the basis of heterogeneity. RESULTS: In total, 21 studies containing 23,848 blood samples from 7 provinces were included in this meta-analysis. The minimum and maximum reported seroprevalences of SFTSV among humans in China were 0.23% and 9.17%, respectively. The overall pooled seroprevalence of SFTSV antibodies was 4.3% (95%CI: 3.2%-5.5%). The pooled prevalence was 5.9% (95%CI: 4.7%-7.0%) in Zhejiang province, 4.9% (95%CI: 4.1-5.8%) in Anhui province, 3.9% (95%CI: 1.3%-6.4%) in Shandong province, and 0.7% (95%CI: 0.2%-1.1%) in Jiangsu province. Stratified by occupation, the pooled prevalence of farmer was 6.1% (95%CI: 3.4%-8.9%) and others (mainly are students) was 3.3% (95%CI: 2.4%-4.2%). Additionally, seroprevalence of SFTSV in people who lived in the same village with the patient were higher than that of people who lived in a different village. Seropositive rates in sampling years after 2012 were higher than that before 2012. The prevalence of SFTSV did not differ by age or gender. Sensitive analysis by omitting one study at a time indicated the results of the pooled seroprevalence were robust. CONCLUSIONS: Seroprevalence of SFTSV among healthy population in central and eastern China is high. Surveillance efforts on mild or asymptomatic infections among endemic persons are needed.

[Synthesis, structure characterization and, fluorescence studies of the complexes of europium with phenylglyoxylic acid, 1,10-phenanthroline and triphenyl phosphine oxide].

Three novel europium complexes, Eu-L, EuL3phen and EuL2 (TPPO)2NO3, were synthesized (HL = phenylglyoxylic, phen= 1,10-phenanthroline, and TPPO = triphenyl phosphine oxide). The complexes were characterized by elemental analysis, conductivity, IR, and 1H NMR. The IR spectra indicated that all the complexes have a larger deltaupsilon(upsilon(as) (CO2-) - upsilon(s)(CO2-) than that of NaL, and carboxylate ions in the phenylglyoxyate coordinated as unidentate ligands. And alpha-aeto also coordinated with the europium ions. In 1H NMR, the signals of hydrogens in the phenylglyoxyate shifted toward upfield, and those in phen or TPPO slightly shifted. The excitation and emission spectra were recorded at room temperature, and the excitation spectra showed that the optimum excitation wavelengths were 374.0, 358.2 and 383.4 nm, Five emission bands of the complexes due to 5D(0)-7F(0), 5D(0)-7F(1), 5D(0)-7F(2), 5D(0)-7F(3) and 5D(0)-7F(4) transitions were observed in the region of 550-720 nm (Eu-L: 577.8, 590.2, 614.0, 648.4 and 695.4 nm; EuL3phen: 578.0, 588.4, 591.6, 611.2, 617.0, 649.4, 687.6 and 698.6 nm; EuL2 (TPPO)2NO3: 577.8, 590.4, 614.6, 649.2 and 697.6 nm). The emission intensities of europium ions were obviously sensitized by TPPO.

[Study on the relationship between contents of poison in fishes and the levels of ocean pollutants in Zhoushan Fishery].

OBJECTIVE: To investigate the contents of poison in fishes in the Zhoushan Fishery and to analysis its relationship with the degree of ocean pollution. METHOD: Nine kinds of major fishes in the Zhoushan Fishery were sampled and tested. Canonical correlation was conducted to evaluate the correlation between contents of poison in fishes and the degree of ocean pollution. RESULTS: The average contents of nickel among 9 kinds of fishes exceeded normal value by 1.177 times. No significantly statistical differences were found between the levels of poison contents in nine kinds of major fishes during 1997 to 2003 in the Zhoushan Fishery (the P values are all less than 0.05), except that the levels of cadmium and hydrargyrum in some fishes (the P values are all more than 0.05). The coefficient of fishes accumulated from different poisons ranged from 101.80 to 71 210.97. The canonical correlation coefficients of the variables of the contents of plumbum, arsenic and benzene hexachloride, chlorophennothane between fishes and ocean were 0.784 and 0.808 respectively. Positive correlation between them was shown (chi(2) = 20.994, P < 0.01; chi(2) = 38.017, P < 0.01). CONCLUSION: The sanitary quality indexes of all poisons which had been tested fell in the normal ranges except for nickel. The degrees of poisons accumulated among distinct fishes varied, showing the relationship of medium positive correlation between the poison contents of fishes and the degree of the ocean pollution.