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Nashua, NH, United States

Zlatarski V.N.,1131 Fales Rd | Stake J.L.,Rivier College
Geologica Belgica | Year: 2012

Though scientific interest in scleractinian corals originated in the 16th century, the knowledge base continues to grow and is far from complete. The progress of the research on these organisms is represented here as an exponential process and its history may be divided into three periods. In the beginning, Plant period (1576-1727), these organisms were interpreted as plants. The Animal period (1727-2007) brought in their consideration as animals and includes three phases that introduce new research approaches (phase 1: variability, microstructure, transplantation; phase 2: multiple skeletal characters, global spatial and temporal attention; phase 3: life history, molecular biology). Recently, the number of sources of scleractinian knowledge has increased to five: morphology, paleobiology, ecology, life history and molecular biology. Scleractinian corals are no longer considered alone but as holobionts, along with their symbiotic zooxanthallae and other associated microbiota. The accumulated multidisciplinary data and new integrative concepts urge a holistic interpretation and have been indicating (since 2007) the commencement of the present, Holistic period. This analysis of the current status of scleractinian knowledge provides a list of proposed directions for future research.

Riabov V.V.,Rivier College
27th Congress of the International Council of the Aeronautical Sciences 2010, ICAS 2010 | Year: 2010

Hypersonic flows of argon, nitrogen, oxygen, and carbon dioxide near a toroidal ballute have been investigated numerically using the Direct Simulation Monte-Carlo (DSMC) technique under transition rarefied-gas flow conditions (Knudsen numbers from 0.005 to 10). Strong influences of the geometrical factor (a ratio of the distance between the axis of symmetry and the torus disk center, and the torus radius) and the Knudsen number on the flow structure (the shape of shock waves and the stagnation point location), skin friction, pressure distribution, and drag have been found. © 2010 by the International Council of Aeronautical Sciences - ICAS.

Philip B.N.,Rivier College
Methods in molecular biology (Clifton, N.J.) | Year: 2011

The discovery of RNAi, in which double-stranded RNA (dsRNA) suppresses the translation of homologous mRNA, has had a huge impact on evolutionary genetics by enabling the analysis of loss-of-function phenotypes in organisms in which classical genetic analysis is laborious or impossible. In this chapter, we discuss an RNAi method via simple dsRNA injection in the red flour beetle, Tribolium castaneum. Tribolium is gaining popularity in evolutionary genetics due in part to the ease of RNAi application. We describe procedures for dsRNA synthesis and injection and provide a description of the injection apparatus. In addition, we detail two methods to validate the efficacy of RNAi (real-time PCR and western blot analyses). Although this chapter focuses mainly on Tribolium, many of the molecular biology and injection procedures described here are applicable to other organisms with some modifications. A few notes regarding dsRNA injection in other species are also included.

Riabov V.V.,Rivier College
AIP Conference Proceedings | Year: 2011

The Direct Simulation Monte-Carlo (DSMC) technique is used for numerical analysis of rarefied-gas hypersonic flows near a blunt plate, wedge, two side-by-side plates, disk, torus, and rotating cylinder. The role of various similarity parameters (Knudsen and Mach numbers, geometrical and temperature factors, specific heat ratios, and others) in aerodynamics of the probes is studied. Important kinetic effects that are specific for the transition flow regime have been found: non-monotonic lift and drag of plates, strong repulsive force between side-by-side plates and cylinders, dependence of drag on torus radii ratio, and the reverse Magnus effect on the lift of a rotating cylinder. The numerical results are in a good agreement with experimental data, which were obtained in a vacuum chamber at low and moderate Knudsen numbers from 0.01 to 10. © 2011 American Institute of Physics.

Goto S.G.,Osaka City University | Goto S.G.,Ohio State University | Philip B.N.,Miami University Ohio | Philip B.N.,Rivier College | And 4 more authors.
Journal of Insect Physiology | Year: 2011

Aquaporins (AQPs) are water channel proteins facilitating movement of water across the cell membrane. Recent insect studies clearly demonstrate that AQPs are indispensable for cellular water management under normal conditions as well as under stress conditions including dehydration and cold. In the present study we cloned an AQP cDNA from the Antarctic midge Belgica antarctica (Diptera, Chironomidae) and investigated water transport activity of the AQP protein and transcriptional regulation of the gene in response to dehydration and rehydration. The nucleotide sequence and deduced amino acid sequence of the cDNA showed high similarity to AQPs in other insects and also showed characteristic features of orthodox AQPs. Phylogenetic analysis revealed that Belgica AQP is a homolog of dehydration-inducible AQP of another chironomid, Polypedilum vanderplanki. A swelling assay using a Xenopus oocyte expression system verified that Belgica AQP is capable of transporting water, but not glycerol or urea. The AQP mRNA was detected in various organs under non-stressed conditions, suggesting that this AQP plays a fundamental role in cell physiology. In contrast to our expectation, AQP transcriptional expression was not affected by either dehydration or rehydration. © 2011 Elsevier Ltd.

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