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QD - Chemistry acquired during June 2017

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Transition metal catalyzed pyrimidine, pyrazine, pyridazine and triazine synthesis
Wu, Xiao-Feng, 1985-
Amsterdam, Netherlands ; Elsevier, [2017]
Kresge QD401 .W89 2017

Characterization of the effector-mediated activation of AphB, a LysR-type transcriptional regulator from V.cholerae
Privett, Britney Rose, author
"AphB, a LysR-type transcriptional regulator (LTTR), is a global transcriptional regulator in V. cholerae activated under conditions of low pH and anaerobiosis. AphB regulates the virulence cascade in V. cholerae through the tcpPH promoter resulting in expression of two virulence factors, toxin co-regulated pilus and cholera toxin, both essential for progression of the disease cholera. Additionally, AphB regulates genes involved in cellular homeostasis. This work reveals the regulatory mechanism of AphB as well as provides a potential link between the ancestral role of AphB and its role in initiation of the virulence cascade in V. cholerae. Using the automated docking tool, AutoDock, in conjunction with the experimental binding assay, saturation transfer difference NMR, we identified small molecules that interact with the regulatory domain of AphB. Using in vivo transcriptional assays we demonstrate that one compound, BP-15, has an activating effect on AphB at tcpPH. Docking experiments reveal that this molecule interacts in a newly identified binding pocket within AphB, expanding our understanding of how this protein is regulated. This work demonstrates the effector-mediated transcriptional activation of tcpPH by AphB and lays the groundwork for development of inhibitors of AphB at this promoter. Using in vivo transcriptional assays we demonstrate that AphB is influenced at both tcpPH and VC0770, a putative succinate/acetate transporter, by the presence and presumable uptake of phosphoenolpyruvate:sugar phosphotransferase system (PTS) sugars. This presents a link between carbon metabolism and virulence gene expression in V. cholerae by means of AphB. Additionally, using in vivo reporter assays, HSQC titration experiments, and ELISA binding experiments, we show that AphB is modulated by protein-protein interaction with HPr, a component of the PTS, at the VC0770 promoter. Such an interaction expands our understanding of how AphB is modulated and demonstrates that there are many means for regulation of transcription by AphB. Finally, we have obtained an envelope from small angle x-ray scattering experiments that reveals an AphA-AphB-DNA complex. This is the first visualization of AphB bound to DNA and shows AphB binds in the compact tetramer conformation proposed by the sliding dimer hypothesis. These data add to our knowledge of LTTRDNA interactions."
Rauner D.C. Hist Thesis QD47.5.N43 D3 2017pri

The influence of subglacial hydrology on Arctic tidewater glaciers and fjords
Schild, Kristin M., author
"Mass loss from the Greenland Ice Sheet has accelerated throughout the last decade, predominantly due to a quadrupling of ice discharge by iceberg calving, submarine melting, and meltwater runoff at marine-terminating outlet glaciers. The recent acceleration has been linked to the transport of increasing amounts of meltwater, fuelled by warming temperatures. These processes include enhanced basal sliding, inefficient subglacial drainage networks, and a warming of ocean waters in contact with the glacier terminus. Understanding the impact of meltwater on tidewater glacier dynamics, both subglacially and proglacially, is a key component in predicting glacier health and future sea level rise. However, the spatial and temporal magnitude of this meltwater impact is poorly understood. The goals of this dissertation are to identify how meltwater travels subglacially through a tidewater glacier system, establish a method to monitor tidewater glacier discharge remotely, and calculate the impact of subglacial discharge on terminus stability. The inaccessibility of subglacial and terminus environments prohibits direct hydrological observations. We use combinations of remote sensing, reanalysis models, and in situ fjord data to accomplish these research goals by measuring indicators of subglacial meltwater discharge and fjord circulation (sediment plumes exiting the terminus and the movement of small icebergs in the fjord). By monitoring the timing and duration of plumes exiting a fast-flowing Greenland tidewater glacier, we found short-term variability in meltwater discharge, persistent subglacial pathways, and evidence of over-winter subglacial storage. Using glaciers in Svalbard,we established a new method to determine sediment concentration from Landsat--8 spectral reflectance, and used this sediment concentration to quantify relative seasonal meltwater discharge at tidewater glaciers. Finally, we used the movement of icebergs and ocean temperatures to establish a terminus submarine melt rate for along-terminus fjord circulation, and use this to isolate calving due solely to subglacial meltwater discharge. The results of this dissertation help answer larger questions concerning the controls of water flow under a glacier and how that flow, and fjord circulation, influence glacier stability. Ultimately these results will inform coupled ice-ocean-climate models to predict glacier melt and sea level rise."
Rauner D.C. Hist Thesis QD47.5.N43 D3 2017sch

GRE chemistry test secrets : study guide : your key to exam success : GRE subject exam review for the Graduate Record Examination
written and edited by the Mometrix Exam Secrets Test Prep Team
[Beaumont, Texas] : Mometrix Media LLC, [2015]
Kresge QD42 .M66 2015

Transition metal-catalyzed benzofuran synthesis
Wu, Xiao-Feng, 1985- author
Amsterdam, Netherlands : Elsevier, [2017]
Introduction -- Pd-Catalyzed Benzofuran Synthesis -- Cu-Catalyzed Benzofuran Synthesis -- Other Transition Metal-Catalyzed Benzofuran Synthesis -- Traditional Synthesis of Benzo[b]furans -- Summary and Outlook.
Kresge QD405 .W79 2017

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