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Phylogenetics has a crucial role in genomic epidemiology. Enabled by unparalleled volumes of genome sequence data generated to study and help contain the COVID-19 pandemic, phylogenetic analyses of SARS-CoV-2 genomes have shed light on the virus’s origins, spread, and the emergence and reproductive success of new variants. However, most phylogenetic approaches, including maximum likelihood and Bayesian methods, cannot scale to the size of the datasets from the current pandemic. We present ‘MAximum Parsimonious Likelihood Estimation’ (MAPLE), an approach for likelihood-based phylogenetic analysis of epidemiological genomic datasets at unprecedented scales. MAPLE infers SARS-CoV-2 phylogenies more accurately than existing maximum likelihood approaches while running up to thousands of times faster, and requiring at least 100 times less memory on large datasets. This extends the reach of genomic epidemiology, allowing the continued use of accurate phylogenetic, phylogeographic and phylodynamic analyses on datasets of millions of genomes.

Parabens are considered one of the ideal preservatives in numerous consumer products due to their high antimicrobial properties. Nevertheless, parabens have the following potentially detrimental effects on human health such as adverse effects on male reproductive system, or accelerated skin aging process and breast cancer. Here, ultra‐high performance liquid chromatography (UHPLC) coupled with a triple quadrupole mass spectrometry (MS/MS) combined with a solid‐phase extraction procedure was optimized for measuring seven parabens in surface water and proposed as a modified analytical method. The optimized protocol was validated according to the requirements of European standard SANTE/12682/2019. The limits of detection and quantification of the method obtained were 0.04 and 0.82 ng L‐1, respectively. The validated method was applied to analyzing surface water samples collected in Hanoi, Vietnam, indicating not only the presence of seven targeted parabens but also the prevalence of methylparaben in all water samples.

Eight compounds, including 11β,13‐dihydrovernolide (1), apigenin (2), kaempferol (3), quercetin 3‐O‐methyl ether (4), quercetin (5), syringaresinol‐β‐ᴅ‐glucoside (6), 3‐hydroxy‐1‐(4‐hydroxy‐3‐methoxyphenyl)‐2‐[4‐(3‐hydroxy‐1‐(E)‐propenyl)‐2,6‐dimethoxyphenoxy]propyl‐β‐ᴅ‐glucopyranoside (7), and 5‐(methoxymethyl)‐1H‐pyrrole‐2‐carbaldehyde (8) were isolated from the aerial part of Vernonia gratiosa. Their chemical structures were identified by NMR experiments along with the comparison of their spectroscopic data with those reported in the literature. In addition, all compounds were evaluated for their inhibitory effects on α‐glucosidase and xanthine oxidase. Among them, only compound 7showed the significant inhibition of α‐glucosidase with an IC50value of 47.08 ± 3.98 μg/mL and xanthine oxidase activity with an IC50value of 26.92 ± 1.04 μg/mL. Compounds 1‐5were firstly isolated from V. gratiosa, while compounds 6‐8were reported from the genus for the first time. This is the first study about this species growing in Vietnam.

Tools, rules and incentives are buckling under the flood of coronavirus genome sequences — to help control the pandemic, researchers need new approaches.

Wastewater from fish sauce‐manufacturing Phung Hung Ltd. Company with high salinity has been treated applying the electrochemical oxidation process, using a Ti/CeO2‐Pt anode and different cathodes: copper, stainless steel and copper‐zinc alloy. The pH value and the applied current density have been also examinated. All three cathodes can be used for the organic pollutant electro‐oxidation, however Cu/Zn cathode exhibits a higher efficiency on by‐product nitrate removal. The investigation on the pH and current density showed that the electro‐oxidation process was favorably occurred at pH8 and 30 mA/cm2. After 60 min of electrolysis, ammonia, total nitrogen and COD can be discharged into the A column level of QCVN/11‐2015/BTNMT.

Hedera nepalensisis commonly used as a traditional medicine for the treatment of several diseases.In this research, the efficient characterization of chemical constituents, especially triterpenoid saponins, contained in H. nepalensisextract was established by applying ultra‐high‐performance liquid chromatography‐quadrupole time‐of‐flight tandem mass spectrometry method (UHPLC‐Q‐TOF‐MS/MS). As a result, a total of 45 compounds including 21 triterpene saponins were tentatively elucidated based on MS and MS/MS data, in which eight structures have been reported for the first time. This study provided an efficient analysis strategy to rapidly determine the chemical constituents and laid a foundation for future study of H. nepalensisplanted in Northern Vietnam and other Hederaspecies.

Model-based molecular phylogenetics plays an important role in comparisons of genomic data, and model selection is a key step in all such analyses. We present ModelFinder, a fast model-selection method that greatly improves the accuracy of phylogenetic estimates by incorporating a model of rate heterogeneity across sites not previously considered in this context and by allowing concurrent searches of model space and tree space.

Summary: IQPNNI is a program to infer maximum-likelihood phylogenetic trees from DNA or protein data with a large number of sequences. We present an improved and MPI-parallel implementation showing very good scaling and speedup behavior. Availability: IQPNNI (http://www.bi.uni-duesseldorf.de/software/iqpnni) is written in C++, executable on UNIX/Linux, Windows and MacOS systems. (Free) MPI libraries can be found at http://www.lam-mpi.org/mpi/implementations/. Contact: haeseler@cs.uni-duesseldorf.de