Immunogenicity and safety of a SARS-CoV-2 mRNA vaccine (SYS6006) in healthy Chinese participants: A randomized, observer-blinded, placebo-controlled phase 2 clinical trial.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine enables quick upgrade of antigen sequence to combat emerging new variants. In an observer-blinded, randomized, placebo-controlled phase 2 trial, immunologically naïve 300 adults and 150 older participants were enrolled and randomized (1:1:1) to receive two doses of 20 µg or 30 µg of a SARS-CoV-2 mRNA vaccine (SYS6006) or placebo. Adverse events (AEs) were recorded through 30 days after the second dose. Live virus neutralizing antibody (Nab), S1 protein-specific binding antibody (S1-IgG) and cellular immunity were tested. Results showed that robust wild-type Nab response was elicited with geometric mean titers of 91.3 and 84.9 in the adults, and 74.0 and 115.9 in the elders, 14 days following the second dose (Day 35) in the 20-µg and 30-µg groups, respectively. All seroconverted for wild-type Nab except two participants. Nab against Omicron BA.5 was mild. Robust wild-type S1-IgG response was induced with geometric mean concentrations of 2751.0 and 3142.2 BAU/mL in adults, and 2474.1 and 2993.5 BAU/mL in elders at Day 35 in the 20-µg and 30-µg groups, respectively. S1-IgG against Omicron BA.2 was induced. Cellular immunity was elicited, particularly in enzyme-linked immunospot assay. The most frequent AEs were injection-site pain and fever. Most reported AEs were grade 1 or grade 2. The AE incidences were similar following the first dose and second dose. No vaccination-associated serious AE was reported. In conclusion, two-dose vaccination with SYS6006 demonstrated good safety, tolerability and immunogenicity in immunologically naïve healthy participants aged 18 years or more.

Fisheye lens-based UWOC system with an FOV of ±90°.

The link alignment is a challenge in underwater wireless optical communication (UWOC). This paper proposes a UWOC system adopting a fisheye lens with a field of view (FOV) of ±90° at the receiver to alleviate alignment requirement, and a mobile scanning device (MSD) is exploited to track the variation of the imaging position generated by the fisheye lens due to different incidence angles. In a 7-m tap water channel, a transmission with a data rate of 400 Mbps and an FOV of ±90° is realized with 16-quadrature amplitude modulating-orthogonal frequency division multiplexing (16-QAM-OFDM) modulation and orthogonal matching pursuit (OMP) channel estimation algorithm.

90-m/560-Mbps underwater wireless optical communication utilizing subband multiple-mode full permutation CAP combined with an SNR-weighted detector and multi-channel DFE.

In this paper, a joint signal processing scheme including a subband multiple-mode full permutation carrierless amplitude phase modulation (SMMP-CAP), signal-to-noise ratio weighted detector (SNR-WD), and multi-channel decision feedback equalizer (MC-DFE) is proposed to mitigate the bandwidth limitation of a high-speed long-reach underwater wireless optical communication (UWOC) system. Referring to the trellis coded modulation (TCM) subset division strategy, 16 quadrature amplitude modulation (QAM) mapping set is divided into four 4-QAM mapping subsets by SMMP-CAP scheme. An SNR-WD and an MC-DFE are employed to enhance the demodulation effect of this system in a fading channel. In a laboratory experiment, the minimal required received optical powers (ROPs) for data rates of 480 Mbps, 600 Mbps, and 720 Mbps, at hard-decision forward error correction (HD-FEC) threshold of 3.80 × 10-3, are -32.7 dBm, -31.3 dBm, and -25.5 dBm, respectively. Moreover, the proposed system successfully achieves a data rate of 560 Mbps in a swimming pool with a transmission distance up to 90 m and a total attenuation measured to be 54.64 dB. To the best of our knowledge, this is the first time to demonstrate a high-speed, long-distance UWOC system by employing an SMMP-CAP scheme.

Novosphingobium ovatum sp. nov., isolated from a freshwater mesocosm.

A bacterial strain, designated FSY-8T, was isolated from a freshwater mesocosm in Taiwan and characterized using the polyphasic taxonomy approach. Cells of strain FSY-8T were aerobic, Gram-stain-negative, rod-shaped, non-motile and formed yellow coloured colonies on Reasoner's 2A agar. Growth occurred at 20-40 °C (optimum, 30-37 °C) and pH 5-7 (optimum, pH 6) and in the presence of 0-0.5 % NaCl (optimum, 0 %, w/v). The major fatty acids (>10 %) of strain FSY-8T were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c). The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine, sphingoglycolipid, diphosphatidylglycerol, an uncharacterized aminophospholipid, an uncharacterized glycolipid and an uncharacterized lipid. The major polyamine was spermidine. The major isoprenoid quinone was Q-10. The DNA G+C content was 64.8 mol %. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain FSY-8T formed a phylogenetic lineage in the genus Novosphingobium. Strain FSY-8T showed 71.6-77.2 % average nucleotide identity and 19.9-22.8 % digital DNA-DNA hybridization identity with the strains of other Novosphingobium species. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain FSY-8T should be classified in a novel species of the genus Novosphingobium, for which the name Novosphingobium ovatum sp. nov. is proposed. The type strain is FSY-8T (=BCRC 81051T=LMG 30053T=KCTC 52812T).

Sandaracinomonas limnophila gen. nov., sp. nov., a new member of the family Cytophagaceae isolated from a freshwater mesocosm.

A bacterial strain designated FSY-15T was isolated from a freshwater mesocosm in Taiwan and characterised using a polyphasic taxonomic approach. Cells of strain FSY-15T were Gram-negative, aerobic, non-spore forming, non-motile rods and formed orange coloured colonies. Growth occurred at 20-30 °C (optimum, 25 °C), at pH 6-7.5 (optimum, pH 7) and with 0-0.5 % NaCl (optimum, 0 %). Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain FSY-15T formed a phylogenetic lineage in the the family Cytophagaceae. Strain FSY-15T was most closely related to the genera Pseudarcicella and Arcicella, and the levels of 16S rRNA gene sequence identity with respect to members of related genera are less than 94.1 %. Strain FSY-15T showed less than 68.8 % average nucleotide identity and less than 24.7 % digital DNA-DNA hybridisation identity compared to the type strains of related genera within the family Cytophagaceae. The predominant fatty acids were iso-C15 : 0, C16 : 1ω5c and the major hydroxyl fatty acid was iso-C15 : 0 3-OH. The major isoprenoid quinone was MK-7 and the DNA G+C content was 35.8 mol%. The major polar lipids were phosphatidylethanolamine and several uncharacterised aminophospholipid, aminolipid, phospholipid and lipid. The major polyamine was spermidine. On the basis of the genotypic and phenotypic data, strain FSY-15T represents a novel species of a new genus in the family Cytophagaceae, for which the name Sandaracinomonas limnophila gen. nov., sp. nov. is proposed. The type strain is FSY-15T (=BCRC 81011T =LMG 29732T =KCTC 52445T).

Novosphingobium umbonatum sp. nov., isolated from a freshwater mesocosm.

A bacterial strain designated FSY-9T was isolated from a freshwater mesocosm in Taiwan and characterized to determine its taxonomic affiliation. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain FSY-9T formed a phylogenetic lineage in the genus Novosphingobium. Strain FSY-9T was most closely related to Novosphingobium humi R1-4T with a 97.2 % 16S rRNA gene sequence similarity. Strain FSY-9T showed 71.3-72.6 % average nucleotide identity and 17.7-23.0 % digital DNA-DNA hybridization identity with the strains of other Novosphingobium species. Cells of strain FSY-9T were facultatively anaerobic, Gram-negative, rod-shaped, non-motile and formed light yellow coloured colonies. Growth occurred at 15-37 °C and pH 5.5-7, and in the presence of 0-0.5 % NaCl. The major fatty acids (>10 %) of strain FSY-9T were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C18 : 1ω7c and C16 : 0. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, phosphatidyldimethylethanolamine, sphingoglycolipid, an uncharacterized aminophospholipid, an uncharacterized glycolipid and an uncharacterized lipid. The major polyamine was spermidine. The major isoprenoid quinone was Q-10. The DNA G+C content was 61.5 mol%. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain FSY-9T should be classified as a novel species of the genus Novosphingobium, for which the name Novosphingobium umbonatum sp. nov. is proposed. The type strain is FSY-9T (=BCRC 81052T=LMG 30054T=KCTC 52813T).

Methylobacterium oryzihabitans sp. nov., isolated from water sampled from a rice paddy field.

Strain TER-1T was isolated from water sampled from a rice paddy field in Taiwan. Cells were Gram-negative, aerobic, motile, rod-shaped and formed pink-coloured colonies. Optimal growth occurred at 25-30 °C, pH 6-7 and in the presence of 0.5 % NaCl. Strain TER-1T could grow on C1 compounds such as methanol, formic acid, methylamine and dimethylamine as sole carbon source, and carry methanol dehydrogenase gene, which supports its methylotrophic metabolism. The results of phylogenetic analyses based on the 16S rRNA gene sequence, methanol dehydrogenase gene sequence and coding sequences of 92 protein clusters indicated that strain TER-1T formed a phylogenetic lineage in the genus Methylobacterium. Strain TER-1T was most closely related to Methylobacterium isbiliense AR24T with 96.8 % 16S rRNA gene sequence similarity. Strain TER-1T showed 77.1-82.8 % average nucleotide identity and 16.4-20.2 % digital DNA-DNA hybridization identity with the strains of other Methylobacterium species. The major fatty acid of strain TER-1T was C18 : 1ω7c. The predominant hydroxy fatty acid was C18 : 0 3-OH. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and two uncharacterized lipids. The only isoprenoid quinone was Q-10. The genomic DNA G+C content of strain TER-1T was 71.9 mol%. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain TER-1T should be classified in a novel species of the genus Methylobacterium, for which the name Methylobacterium oryzihabitans sp. nov. is proposed. The type strain is TER-1T (=BCRC 81157T=LMG 30931T=KCTC 62864T).

Pseudomethylobacillus aquaticus gen. nov., sp. nov., a new member of the family Methylophilaceae isolated from an artificial reservoir.

A bacterial strain, designated H-5T, was isolated from an artificial reservoir in Taiwan and characterized using a polyphasic taxonomic approach. Cells of strain H-5T were Gram-stain-negative, aerobic, motile by means of a single polar flagellum, rod-shaped, covered by large capsules and formed white colonies. Growth occurred at 15-30 °C (optimum, 25 °C), at pH 6-8 (optimum, pH 7) and with 0-0.5 % NaCl (optimum, 0 %). Phylogenetic analyses based on the 16S rRNA gene, the methanol dehydrogenase gene and the coding sequences of 92 protein clusters indicated that strain H-5T was affiliated with genera in the family Methylophilaceae in the class Betaproteobacteria. Strain H-5T was most closely related to Methylobacillus methanolivorans ZT with a 95.0 % 16S rRNA gene sequence similarity. Strain H-5T showed less than 73.7 % average nucleotide identity and less than 23.6 % digital DNA-DNA hybridization identity compared to the strains of related genera within the family Methylophilaceae. The predominant fatty acids were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. The major isoprenoid quinone was Q-8 and the DNA G+C content was 58.3 mol%. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, one uncharacterized aminophospholipid, one uncharacterized phospholipid and one uncharacterized lipid. On the basis of the genotypic and phenotypic data presented here, strain H-5T represents a novel species of a new genus in the family Methylophilaceae, for which the name Pseudomethylobacillus aquaticus gen. nov., sp. nov. is proposed. The type strain is H-5T (=BCRC 81154T=KCTC 62865T).

Corn stover pretreatment by inorganic salts and its effects on hemicellulose and cellulose degradation.

Inorganic salts, NaCl, KCl, CaCl(2), MgCl(2), FeCl(2), FeSO(4), FeCl(3), and Fe(2)(SO(4))(3), were studied as catalysts for the degradation of hemicellulose in corn stover. FeCl(3) significantly increased the hemicellulose degradation in aqueous solutions heated between 140 and 200 degrees C with high xylose recovery and low cellulose removal, amounting to approximately 90% and <10%, respectively. Hemicellulose removal increased 11-fold when the corn stover was pretreated with 0.1 M FeCl(3) compared to pretreatment with hot water under otherwise the same conditions, which was also 6-fold greater than pretreatment with dilute sulfuric acid at the same pH. Optimum pretreatment conditions were found where the corn stover was pretreated with 0.1 M FeCl(3) at 140 degrees C for 20 min. Under such conditions, 91% of hemicellulose was removed, and the recovery of monomeric and oligomeric xylose in liquid fraction achieved 89%, meanwhile, only 9% of cellulose was removed.