Eurotatorian paraphyly: Revisiting phylogenetic relationships based on the complete mitochondrial genome sequence of Rotaria rotatoria (Bdelloidea: Rotifera: Syndermata)

<p>Abstract</p> <p>Background</p> <p>The Syndermata (Rotifera+Acanthocephala) is one of the best model systems for studying the evolutionary origins and persistence of different life styles because it contains a series of lineage-specific life histories: Monogononta (cyclic parthenogenetic and free-living), Bdelloidea (entirely parthenogenetic and mostly benthic dweller), Seisonidea (exclusively bisexual and epizoic or ectoparasitic), and Acanthocephala (sexual and obligatory endoparasitic). Providing phylogenetic resolution to the question of Eurotatoria (Monogononta and Bdelloidea) monophyly versus paraphyly is a key factor for better understanding the evolution of different life styles, yet this matter is not clearly resolved. In this study, we revisited this issue based on comparative analysis of complete mitochondrial genome information for major groups of the Syndermata.</p> <p>Results</p> <p>We determined the first complete mitochondrial genome sequences (15,319 bp) of a bdelloid rotifer, <it>Rotaria rotatoria</it>. In order to examine the validity of Eurotatoria (Monogononta and Bdelloidea) monophyly/paraphyly, we performed phylogenetic analysis of amino acid sequences for eleven protein-coding genes sampled from a wide variety of bilaterian representatives. The resulting mitochondrial genome trees, inferred using different algorithms, consistently failed to recover Monogononta and Bdelloidea as monophyletic, but instead identified them as a paraphyletic assemblage. Bdelloidea (as represented by <it>R. rotatoria</it>) shares most common ancestry with Acanthocephala (as represented by <it>L. thecatus</it>) rather than with monogonont <it>B. plicatilis</it>, the other representative of Eurotatoria.</p> <p>Conclusion</p> <p>Comparisons of inferred amino acid sequence and gene arrangement patterns with those of other metazoan mtDNAs (including those of acanthocephalan <it>L. thecatus </it>and monogonont <it>B. plicatilis</it>) support the hypothesis that Bdelloidea shares most common ancestry with Acanthocephala rather than with Monogononta. From this finding, we suggest that the obligatory asexuality of bdelloideans may have secondarily derived from some other preexisting condition in earlier lineage of rotifers. Providing a more complete assessment of phylogenetic relationships and inferring patterns of evolution of different types of life styles among Syndermata awaits comparisons requiring mitochondrial genome sequencing of Seisonidea.</p

A comparative study of the use of executive information systems between Korea and the United States

Since their conception, EIS have been developed and adopted in many firms. The importance of EIS is now increasing with the need of accessing data from many sources under the high-velocity environment. Although many of the Korean firms are now in the process of introducing EIS with the faster growing economy, most research has been conducted on the use of EIS in Western firms. This study aims to explore the current state of EIS usage in Korean firms and make a comparison with that of the United States. Based upon Watson et al. (1992), a questionnaire instrument was constructed. The questionnaires were distributed to 136 Korean companies that were reported to use EIS and 50 of the questionnaires returned. We found that there were many differences in the use of EIS between Korea and the United States. This was mainly due to the fact that the use of EIS in Korea was at a very early stage and executives in Korea did not realize and/or understand the benefits from the use of EIS yet

A monolithic and flexible fluoropolymer film microreactor for organic synthesis applications

A photocurable and viscous fluoropolymer with chemical stability is a highly desirable material for fabrication of microchemical devices. Lack of a reliable fabrication method, however, limits actual applications for organic reactions. Herein, we report fabrication of a monolithic and flexible fluoropolymer film microreactor and its use as a new microfluidic platform. The fabrication involves facile soft lithography techniques that enable partial curing of thin laminates, which can be readily bonded by conformal contact without any external forces. We demonstrate fabrication of various functional channels (similar to 300 mu m thick) such as those embedded with either a herringbone micromixer pattern or a droplet generator. Organic reactions under strongly acidic and basic conditions can be carried out in this film microreactor even at elevated temperature with excellent reproducibility. In particular, the transparent film microreactor with good deformability could be wrapped around a light-emitting lamp for close contact with the light source for efficient photochemical reactions with visible light, which demonstrates easy integration with optical components for functional miniaturized systems.open1112Ysciescopu

1,4-Bis(4-pyridylsulfanylmeth­yl)benzene

In the title compound, C18H16N2S2, a crystallographic inversion centre lies at the centre of the benzene ring, and the two terminal 4-mercaptopyridyl groups adopt an anti geometry. Each benzene ring makes a dihedral angle of 55.4 (1)° with the plane of the benzene fragment. The crystal structure is stabilized by C—H⋯π inter­actions between a benzene H atom and a pyridyl ring of a neighbouring mol­ecule. In addition, the crystal structure exhibits inter­molecular C—H⋯N inter­actions

An exact solution of the higher-order gravity in standard radiation-dominated era

We report that the standard evolution of radiation-dominated era (RDE) universe $a \propto t^{1/2}$ is a sufficient condition for solving a sixth order gravitational field equation derived from the Lagrangian containing $B R^{ab}R_{ab} + C R {R^{;c}}_{c}$ as well as a polynomial $f(R)$ for a spatially flat radiation FLRW universe. By virtue of the similarity between $R^{ab}R_{ab}$ and $R^2$ models up to the background order and of the vanishing property of ${R^{;c}}_{c}$ for $H = 1/(2t)$, the analytical solution can be obtained from a special case to general one. This proves that the standard cosmic evolution is valid even within modified gravitational theory involving higher-order terms. An application of this background solution to the tensor-type perturbation reduces the complicated equation to the standard second order equation of gravitational wave. We discuss the possible ways to discriminate the modified gravity model on the observations such as the gravitational wave from the disturbed universe and primordial abundances

2,9,16,19,22,25-Hexaoxatetra­cyclo­[24.4.0.24,7.010,15]dotriaconta-1(26),4,6,10(15),11,13,27,29,31-nona­ene

The title 22-crown-6 unit, C26H28O6, comprising of three benzo groups and triethyl­ene glycol, was prepared by the reaction of α,α′-dibromo-p-xylene with 1,8-bis­(2-hydroxy­phen­oxy)-3,6-dioxaoctane in the presence of Cs2CO3 with tetra­hydro­furan (THF) and recrystallized from dichloro­methane–hexane (1:20 v/v) at room temperature. In the mol­ecular structure, two O atoms of the central ethyl­ene glycol in the triethyl­ene glycol unit exhibit exo conformations due to intra­molecular C—H⋯O inter­actions. A number of C—H⋯O and C—H⋯π inter­molecular inter­actions contribute to the stabilization of the crystal packing

Triflumizole

In the title compound {systematic name: 4-chloro-N-[1-(1H-imidazol-1-yl)-2-propoxyethyl­idene]-2-(trifluoro­meth­yl)aniline}, C15H15ClF3N3O, the dihedral angle between the aniline and imidazole ring planes is 81.80 (4)°. In the crystal structure, weak inter­molecular C—H⋯X (X = N, O or F) hydrogen bonds and C—H⋯π inter­actions help to consolidate the packing

Toward a Standardized Strategy of Clinical Metabolomics for the Advancement of Precision Medicine

Despite the tremendous success, pitfalls have been observed in every step of a clinical metabolomics workflow, which impedes the internal validity of the study. Furthermore, the demand for logistics, instrumentations, and computational resources for metabolic phenotyping studies has far exceeded our expectations. In this conceptual review, we will cover inclusive barriers of a metabolomics-based clinical study and suggest potential solutions in the hope of enhancing study robustness, usability, and transferability. The importance of quality assurance and quality control procedures is discussed, followed by a practical rule containing five phases, including two additional "pre-pre-" and "post-post-" analytical steps. Besides, we will elucidate the potential involvement of machine learning and demonstrate that the need for automated data mining algorithms to improve the quality of future research is undeniable. Consequently, we propose a comprehensive metabolomics framework, along with an appropriate checklist refined from current guidelines and our previously published assessment, in the attempt to accurately translate achievements in metabolomics into clinical and epidemiological research. Furthermore, the integration of multifaceted multi-omics approaches with metabolomics as the pillar member is in urgent need. When combining with other social or nutritional factors, we can gather complete omics profiles for a particular disease. Our discussion reflects the current obstacles and potential solutions toward the progressing trend of utilizing metabolomics in clinical research to create the next-generation healthcare system.11Ysciescopu

Diclomezine: 6-(3,5-dichloro-4-methyl­phen­yl)pyridazin-3(2H)-one

In the title compound, C11H8Cl2N2O, the benzene and pyridazine rings are tilted by 8.6 (1)° relative to each other. In the crystal, pairs of inter­molecular N—H⋯O hydrogen bonds form centrosymmetric dimers. π–π contacts with centroid–centroid distances of 3.698 (2) and 3.751 (1) Å and halogen–halogen inter­actions [3.379 (1) Å] also stabilize the structure