The mitochondrial genome of Atrocalopteryx melli Ris, 1912 (Zygoptera: Calopterygidae) via Ion Torrent PGM NGS sequencing

The mitochondrial genome of Atrocalopteryx melli was sequenced and assembled via Next-Generation Sequencing (NGS) and iteratively assembly process with a reference seed. This genome is 15,562 by long and A + T biased (71%), with 37 genes arranged in common order of Odonata. All protein-coding genes are initiated by typical "ATN" codon, and 9 genes are terminated with a complete stop codon, except nad4, nad5, cox2, and cox3, which are terminated with an incomplete codon "T(aa)". The S5 intergenic spacer is absent in this genome, supporting that lacking of S5 as a specific character for damselflies. The A + T rich region of A. melli is 267 bp longer than that of A. atrata. This mitogenome provides new molecular information for understanding of A. melli and Atrocalopteryx

Competitive dominance of

Microcystis aeruginosa and Raphidiopsis raciborskii (previously Cylindrospermopsis raciborskii) are both common bloom-forming cyanobacteria which can coexist but alternatively dominate in freshwater ecosystems. To predict their blooming dynamics, we need to understand the potential environmental factors determining their succession. In the present study, we examined the pairwise competition of the three M. aeruginosa strains (FACHB905, 469 and 915) with one R. raciborskii strain (N8) at three temperature levels (16 °C, 24 °C, and 32 °C). We found that the competitive ability of three Microcystis strains were highly variable. M. aeruginosa FACHB905 was the strongest competitor among them which can finally exclude R. raciborskii N8 regardless of initial biovolume ratios and temperature levels. The competitive exclusion of N8 by 915 also was observed at 24 °C, but they coexisted at 16 °C and 32 °C. We observed that M. aeruginosa FACHB469 and R. raciborskii N8 were able to coexist under all the temperature levels, and M. aeruginosa FACHB469 was the weakest competitor among the three M. aeruginosa strains. Rates of competitive exclusion (RCE) showed that temperature affects the competition between three M. aeruginosa strains and R. raciborskii N8. M. aeruginosa strains always grew quickly at 24 °C and significantly enlarged its dominance in the co-culture system, while R. raciborskii N8 was able to maintain its initial advantages at both 16 and 32 °C. The competitive advantage of M. aeruginosa FACHB905 may be explained by allelopathic interactions through its allelochemicals and other secondary metabolites other than microcystin. We concluded that both strain difference and temperature can affect the competition between M. aeruginosa and R. raciborskii. Our results highlighted the complexity of cyanobacterial dynamics in waterbodies where there exist multiple strains

Do bigheaded carp act as a phosphorus source for phytoplankton in (sub)tropical Chinese reservoirs?

Stocking of bigheaded carp (mainly Hypophthalmichthys nobilis and H. molitrix) is commonly used in (sub)tropical Chinese reservoirs to control phytoplankton, but with ambiguous results. Whether these carp act as a phosphorus (P) source or sink for phytoplankton is debated. We compared the trophic structures in twenty-three reservoirs with different nutrient concentrations in the flood season (after bigheaded carp introduction) with the dry season (after bigheaded carp harvesting). Fish biomass was positively related to TP, and the slope of the relationship showed no difference between seasons. Bigheaded carp harvesting exceeded the amount introduced, which may explain an observed lower intercept of the relationship and fish biomass to the TP ratio in the dry season. Fish predation pressure on zooplankton (fish: zooplankton biomass ratio as a proxy) was highest in the flood season and increased with TP in both seasons. Accordingly, zooplankton grazing effect on phytoplankton (zooplankton: phytoplankton biomass ratio as a proxy) decreased with fish biomass. Furthermore, both the zooplankton biomass and the zooplankton: phytoplankton biomass ratio were among the lowest reported in the literature for the nutrient range studied. Fish grazing effect on phytoplankton (fish: phytoplankton biomass ratio as a proxy) was also highest in the flood season and decreased with TP in both seasons. Nanoplankton was the dominant phytoplankton group in oligotrophic to mesotrophic reservoirs, while filamentous cyanobacteria dominated in eutrophic reservoirs. Chlorophyll a increased with TP and fish biomass, whereas the yield of chlorophyll a per TP (Chla: TP ratio) increased with fish biomass. Accordingly, both chlorophyll a and the Chla: TP ratio were highest in the flood season. We conclude that bigheaded carp act as P sink at the ecosystem level but as P source for phytoplankton, and enhance the yield of chlorophyll a per TP and thus eutrophication

Effects of Different Processing Methods on Volatile Flavor Components of Zanthoxylum bungeanum Maxim. Extract and Braised Duck Neck

To investigate the effects of crushed water extraction, uncrushed water extraction, crushed alcohol extraction, uncrushed alcohol extraction, pulverized soup post-extraction and unpulverized soup extraction on volatile flavor components of Zanthoxylum bungeanum Maxim. and its ability to confer volatile flavor substances to braised duck neck was studied. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS) were used to determine the differences of main volatile flavor components in brine and braised duck neck under different treatment methods. GC-MS results showed that the main aromatic compounds in Zanthoxylum bungeanum Maxim. were alcohols, hydrocarbons, esters and ethers. Water extraction could improve the dissolution of 4-terpineol and other alcohols, and alcohol extraction could improve the dissolution of pyoletene and other substances. Decoction extraction had a better dissolution effect on ethers, and crushing treatment could effectively promote the dissolution of hydrocarbons and esters, and was not conducive to the retention of volatile components of alcohol and ether in the brine. The main substances in braised duck neck were 4-terpenoid and cineole after brine preparation of Zanthoxylum bungeanum Maxim. extract under different treatment methods. Water extraction could significantly promote the retention of eucalyptol and limonene in braised duck neck. Ethanol extraction improved the effect of anethole in duck neck. Whether Zanthoxylum bungeanum Maxim. was crushed or not had no significant effect on the volatile flavor substances assigned to duck neck by the prepared brine. Based on GC-IMS spectrum analysis, it was found that for the extract, only alcohol extraction showed significant differences. Similarly, only alcohol extraction showed significant difference in braised duck neck. The volatile flavour compounds of different treatments for Zanthoxylum bungeanum Maxim. extract and gives braised duck neck ability has a significant effect of volatile flavor substances

Daphnia diversity on the Tibetan Plateau measured by DNA taxonomy

Daphnia on the Tibetan Plateau has been little studied, and information on species diversity and biogeography is lacking. Here, we conducted a 4-year survey using the barcoding fragment of the mitochondrial COI gene to determine the distribution and diversity of Daphnia species found across the Plateau. Our results show that species richness is higher than previously thought, with total described and provisional species number doubling from 5 to 10. Six of the taxonomic units recovered by DNA taxonomy agreed well with morphology, but DNA barcoding distinguished three clades each for the D.longispina (D.galeata, D.dentifera, and D.longispina) and D.pulex (D.pulex, D. cf. tenebrosa, and D.pulicaria) complexes. The sequence divergence between congeneric species varied within a large range, from 9.25% to 30.71%. The endemic D.tibetana was the most common and widespread species, occurring in 12 hyposaline to mesosaline lakes. The lineage of D.longispina is the first confirmed occurrence in west Tibet

Selecting an appropriate all-oral short-course regimen for patients with multidrug-resistant or pre-extensive drug-resistant tuberculosis in China: A multicenter prospective cohort study

Objectives: Long, ineffective, and toxic regimens hinder the treatment of patients with multidrug-resistant tuberculosis (MDR-TB) and pre-extensive drug-resistant tuberculosis (pre-XDR-TB). Methods: We conducted a multicenter cohort study to prospectively evaluate the safety and efficacy of three 9-month, all-oral, 5-drug regimens. Regimen A (bedaquiline [Bdq]+linezolid [Lzd]+moxifloxacin [Mfx]+cycloserine [Cs]+pyrazinamide [Pza]) and Regimen B (Lzd+Mfx+Cs+clofazimine [Cfz]+Pza) were used to treat MDR-TB patients (Groups A and B, respectively, assigned according to the patient's treatment preference), while Regimen C (Bdq+Lzd+Cs+Cfz+Pza) was used to treat pre-XDR-TB patients (Group C). The primary endpoint was the occurrence of an unfavorable outcome within 12 months of treatment completion, regardless of regimen. Results: A total of 104 patients (34 in Group A, 46 in Group B, and 24 in Group C), with a median age of 35.5 (29.0-54.0) years, were included in the analysis population. At 12 months after treatment completion, five patients were deemed non-assessable. Of the remaining 99 participants, seven (7.1%) had an unfavorable outcome (including two deaths from any cause, four with treatment failure, and one loss to follow-up) and 92 (92.9%) had a favorable outcome. Culture conversion was achieved in 82.5% (80/97) of participants at month 2 and in 97.9% (94/97) of participants at month 6. Adverse events (AEs) resulting in drug adjustment occurred in 69.2% (72/104) of participants, mainly due to Lzd and Pza use. A QT interval prolongation of ≥ 500 ms occurred in 5.8% (6/104) of participants. Conclusion: The primary outcome of the three tailored, 9-month, all-oral, 5-drug regimens was satisfactory in the vast majority of MDR-TB and pre-XDR-TB patients, with manageable and reversible AEs