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Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume Ii Of Ii, National Park Service

Publications (WR)

This document presents the results of surface-water-quality data retrievals for Lake Mead National Recreation Area (LAME) from five of the United States Environmental Protection Agency's (EPA) national databases: (1) Storage and Retrieval (STORET) database management system; (2) River Reach File (RF3); (3) Industrial Facilities Discharge (IFD); (4) Drinking Water Supplies (DRINKS); and (5) Flow Gages (GAGES). This document is one product resulting from a cooperative contractual endeavor between the National Park Service's Servicewide Inventory and Monitoring Program, the National Park Service's Water Resources Division (WRD), and Horizon Systems Corporation to retrieve, format, and analyze water quality data for all units …

Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume I Of Ii, National Park Service

Publications (WR)

This document presents the results of surface-water-quality data retrievals for Lake Mead National Recreation Area (LAME) from five of the United States Environmental Protection Agency's (EPA) national databases: (1) Storage and Retrieval (STORET) database management system; (2) River Reach File (RF3); (3) Industrial Facilities Discharge (IFD); (4) Drinking Water Supplies (DRINKS); and (5) Flow Gages (GAGES). This document is one product resulting from a cooperative contractual endeavor between the National Park Service's Servicewide Inventory and Monitoring Program, the National Park Service's Water Resources Division (WRD), and Horizon Systems Corporation to retrieve, format, and analyze water quality data for all units …

Semiclassical Quantization Of A Nonintegrable System: Pushing The Fourier Method Into The Chaotic Regime, Karl Sohlberg, Randall B. Shirts

Faculty Publications

Semiclassical Einstein–Brillouin–Keller (EBK) quantization of the nonintegrable Hénon–Heiles Hamiltonian succeeds using the Fourier transform method of Martens and Ezra. Two innovations are required for this success: (1) the use of tunneling corrected quantizing actions obtained from an approximate, one-dimensional Hamiltonian and (2) exploitation of intermediate-time approximate quasiperiodicity or "vague tori'' wherein the Fourier transform of chaotic motion over 10–100 vibrational periods allows the determination of frequencies and amplitudes which approximate motion during the time interval. Approximate tori, actions, and EBK energy levels are then straightforward. We use an interpolation method to smooth over small resonance zones that are not expected …

Lag-2 May Encode A Signaling Ligand For The Glp-1 And Lin-12 Receptors Of C-Elegans, Samuel T. Henderson, Dali Gao, Eric J. Lambie, Judith Kimble

Dartmouth Scholarship

The C. elegans lag-2 gene is required for several cell-cell interactions that rely on the receptors GLP-1 and LIN-12. In this paper, we report that lag-2 encodes a putative membrane protein with sequence similarity to Drosophila Delta, a proposed ligand for the Notch receptor. Furthermore, we show that the lag-2 promoter drives expression of a reporter protein in the signaling distal tip cell (DTC) of the DTC/germline interaction. By in situ hybridization, we have found that endogenous lag-2 mRNA is present in the DTC but not the germ line. One fusion protein, called LAG-2::beta-gal(intra), rescues a lag-2 null mutant and …

The Pha-4 Gene Is Required To Generate The Pharyngeal Primordium Of Caenorhabditis-Elegans, Susan E. Mango, Eric J. Lambie, Judith Kimble

Dartmouth Scholarship

In the 4-cell Caenorhabditis elegans embryo, two blastomeres are destined to generate pharyngeal cells, each by a distinct developmental strategy: one pathway is inductive, while the other is autonomous. Here, we identify the pha-4 locus. In animals lacking pha-4 activity, an early step in pharyngeal organogenesis is blocked: no pharyngeal primordium is formed and differentiated pharyngeal cells are absent. Most other tissues are generated normally in pha-4 mutants, including cells related to pharyngeal cells by cell lineage and position. Thus, pha-4 activity is required to form the pharyngeal primordium. We propose that pha-4 marks a convergence of the inductive and …

Sensitivity Of Second Harmonic Generation To Space Charge Effects At Si(111)/Electrolyte And Si(111)/Sio2/Electrolyte Interfaces, P. R. Fischer, J. L. Daschbach, D. E. Gragson, G. L. Richmond

Chemistry and Biochemistry

The potential dependence in the surface second harmonic response from hydrogen terminated n‐Si(111) and oxidized n‐Si(111) surfaces has been examined in aqueous NH₄F and H₂SO₄ solutions. The relative phase of the nonlinear response as measured by rotational anisotropy experiments is found to be highly sensitive to the presence of the oxide and the field applied across the Si(111)/oxide/electrolyte interface. These observations are attributed to field effects within the space–charge region of the semiconductor which vary with the presence and thickness of the insulating oxide layer on the Si(111) surface.

Heterologous Expression Of The Bchm Gene Product From Rhodobacter Capsulatus And Demonstration That It Encodes S-Adenosyl-L-Methionine: Mg-Protoporhyrin Ix Methyltransferase, David Bollivar

Scholarship

No abstract provided.

Use Of An Oriented Transmembrane Protein To Probe The Assembly Of A Supported Phospholipid Bilayer, Paul Brian Contino, Carol A. Hasselbacher, J. B. Alexander Ross, Yale Nemerson

Chemistry and Biochemistry Faculty Publications

Planar-supported phopholipid bilayers formed by te adsorpton of vesicles are increasingly used in the investigation of lipK-ependent reactis. We have studied the way in which these bilayers are forned with phopholipid vesicles coaining the btranembrane protein Tssue Factor (TF). TF complexed with te senne protease, factor Vlla, is the primary initiator of bklod coagulation by way of activation of the zymogen factor X. TF has been shown to orient randomly on the inner and outer leaflets of vesicles. We used proteolytic digestion to produce vesicles in which the exracellular domain of TF is located on the inner leaflet These vesicles …

Crystallization Of Hemoglobins Ii And Iii Of The Symbiont-Harboring Clam Lucina Pectinata, M. A. Doyle, Jacqueline Vitali, J. B. Wittenberg, S. N. Vinogradov, D. A. Walz, B. F.P. Edwards, P. D. Martin

Physics Faculty Publications

Diffraction data to 2.7 A resolution were measured on crystals of the homotetramers of components II and III of the cytoplacmic hemoglobin of the symbiont-harboring clam Lucina pectinata. Even though the crystallization conditions are different and the sequence homology of the two hemoglobins is only 63%, the crystals are isomorphous to each other and to the heterotetramer Hb II/III, implying that the residues primarily involved in the intermolecular interactions and responsible for crystal cohesion may be invariant.

The Structure And Dynamics Of The Cs2 Molecular Ion, Karl Sohlberg, Chan Yibai

Faculty Publications

Several common elementary methods of computing molecular properties, prerequisite to molecular dynamics studies, are tested for their validity for CS+2. Judged sufficiently accurate, these methods are then used to aid in investigating the collisionally activated dissociation of CS+2 upon impact with xenon. Rice–Ramsperger–Kassel–Marcus (RRKM) unimolecular decay rate calculations are presented and compared to experimental studies employing collisional activation. RRKM theory is shown to reproduce the experimental results for collision energies near threshold. When corrected for vibrational anharmonicity, the RRKM calculation shows agreement with the experimental results over a slightly wider range of energies. A discussion is given on the applicability …

Dissection Of An Antibody-Catalyzed Reaction, Jon D. Stewart, Joseph F. Krebs, Gary Siuzdak, Anthony J. Berdis, David B. Smithrud, Stephen J. Benkovic

Chemistry Faculty Publications

Antibody 43C9 accelerates the hydrolysis of a p-nitroanilide by a factor of 2.5 x 10(5) over the background rate in addition to catalyzing the hydrolysis of a series of aromatic esters. Since this represents one of the largest rate accelerations achieved with an antibody, we have undertaken a series of studies aimed at uncovering the catalytic mechanism of 43C9. The immunogen, a phosphonamidate, was designed to mimic the geometric and electronic characteristics of the tetrahedral intermediate that forms upon nucleophilic attack by hydroxide on the amide substrate. Further studies, however, revealed that the catalytic mechanism is more complex and involves …

Circadian Clock Locus Frequency: Protein Encoded By A Single Open Reading Frame Defines Period Length And Temperature Compensation., Benjamin D. Aronson, Keith A. Johnson, Jay C. Dunlap

Dartmouth Scholarship

The frequency (frq) locus encodes a key component, a state variable, in a cellular oscillator generating circadian rhythmicity. Two transcripts have been mapped to this region, and data presented here are consistent with the existence of a third transcript. Analysis of cDNA clones and clock mutants from this region focuses attention on one transcript encoding a protein. FRQ, which is a central clock component: (i) mutations in all of the semidominant frq alleles are the result of single amino acid substitutions and map to the open reading frame (ORF) encoding FRQ; (ii) deletion of this ORF, or a frameshift mutation …

Cystic Fibrosis Transmembrane Conductance Regulator Mutations That Disrupt Nucleotide Binding, James Logan, David Hiestand, Paru Daram, Zhen Huang, Donald D. Muccio, John Hartman, Boyd Haley, William J. Cook, Eric J. Sorscher

Molecular and Cellular Biochemistry Faculty Publications

Increasing evidence suggests heterogeneity in the molecular pathogenesis of cystic fibrosis (CF). Mutations such as deletion of phenylalanine at position 508 (delta F508) within the cystic fibrosis transmembrane conductance regulator (CFTR), for example, appear to cause disease by abrogating normal biosynthetic processing, a mechanism which results in retention and degradation of the mutant protein within the endoplasmic reticulum. Other mutations, such as the relatively common glycine-->aspartic acid replacement at CFTR position 551 (G551D) appear to be normally processed, and therefore must cause disease through some other mechanism. Because delta F508 and G551D both occur within a predicted nucleotide binding …

Coordination Of Selenium To Molybdenum In Formate Dehydrogenase H From Escherichia Coli, Vadim Gladyshev, Sergei V. Khangulov, Milton J. Axley, Thressa A. Stadtman

Vadim Gladyshev Publications

Formate dehydrogenase H from Escherichia col contains multiple redox centers, which include a molybdopterin cofactor, an iron-sulfur center, and a selenocysteine residue (SeCys-140 in the polypeptide chain) that is essential for catalytic activity. Here we show that addition of formate to the native enzyme induces a signal typical of Mo(V) species. This signal is detected by electron pm etc resonance (EPR) spectroscopy. Substitution of 77Se for natural isotope abundance Se leads to transformation of this signal, indicating a direct coordination of Se with Mo. Mutant enzyme with cysteine substituted at position 140 for the selenocysteine residue has decreased catalytic activity …

Production Of Interleukin 10 By Islet Cells Accelerates Immune-Mediated Destruction Of Beta Cells In Nonobese Diabetic Mice., Lise Wogensen, Myung-Shik Lee, Nora Sarvetnick

Journal Articles: Regenerative Medicine

The T helper type 2 (Th2) cell product interleukin 10 (IL-10) inhibits the proliferation and function of Th1 lymphocytes and macrophages (M phi). The nonobese diabetic mouse strain (NOD/Shi) develops a M phi and T cell-dependent autoimmune diabetes that closely resembles human insulin-dependent diabetes mellitus (IDDM). The objective of the present study was to explore the consequences of localized production of IL-10 on diabetes development in NOD/Shi mice. Surprisingly, local production of IL-10 accelerated the onset and increased the prevalence of diabetes, since diabetes developed at 5-10 wk of age in 92% of IL-10 positive I-A beta g7/g7, I-E- mice …

Altering The Rna Binding Specificity Of A Translational Repressor, F Lim, Marc Spingola, D Peabody

Biology Department Faculty Works

The coat proteins of RNA phages MS2 and GA are specific RNA-binding proteins which function to encapsidate viral RNA and to translationally repress synthesis of the viral replicase. The two proteins have highly homologous amino acid sequences, yet they show different RNA binding specificities, recognizing RNA stem-loop structures which differ primarily in the nucleotide sequences of their loops. We sought to convert MS2 coat protein to the RNA binding specificity of GA through the introduction of GA-like amino acid substitutions into the MS2 coat protein RNA-binding site. The effects of the mutations were determined by measuring the affinity of the …

Pancreatic Islet Production Of Murine Interleukin-10 Does Not Inhibit Immune-Mediated Tissue Destruction., Myung-Shik Lee, Lise Wogensen, Judith Shizuru, Michael B.A. Oldstone, Nora Sarvetnick

Journal Articles: Regenerative Medicine

IL-10 inhibits macrophage-dependent antigen presentation, cytokine production, and generation of allospecific cells in vitro. These findings have lead to the widespread expectation that IL-10 may be a useful immunosuppressive agent to inhibit allograft rejection or autoimmunity in vivo. We used two experimental paradigms to study effects of murine IL-10 on in vivo immune responses. First, fetal pancreata or adult pancreatic islets from transgenic mice expressing IL-10 in pancreatic beta cells (Ins-IL-10 mice) were grafted across the MHC barrier to examine if IL-10 could inhibit allograft rejection. Second, Ins-IL-10 mice were crossed with transgenic mice expressing lymphocytic choriomeningitis virus (LCMV) antigens …

Study Of Existing Information Concerning Water Quality Within Lake Mead, Vicki Scharnhorst, Southern Nevada Water Authority

Publications (WR)

The purpose of Task 010A15M of the Southern Nevada Water Authority (SNWA) Treatment and Transmission Facility (TTF) contract is to conduct a study of existing information concerning water quality within Lake Mead and identify additional water quality studies that are needed to supplement existing data.

The objective of this task is not to discuss treatability of the raw water source; this is addressed by Task 010A18M, "Define Water Treatment Requirements." In addition, a narrative on the effect of pending Safe Drinking Water Act amendments and a determination of treated water quality goals is included in Task 010A16M, "Review Safe Drinking …

Separate Metabolic Pathways Leading To Dna Fragmentation And Apoptotic Nuclear Chromatin Condensation, D. Sun, Shibo Jiang, Li-Mou Zheng, David M. Ojcius, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

Apoptosis is the predominant form of cell death observed in a variety of physiological and pathological conditions such as cancer involution, insect metamorphosis, the development of the immune and nervous systems, and embryogenesis. The typical nuclear changes taking place in apoptotic cells include extensive condensation of chromatin and internucleosomal DNA fragmentation into units of 200 base pairs. However, the mechanisms responsible for both chromatin condensation and DNA fragmentation have yet to be elucidated. In this study, micrococcal nuclease and the divalent cations, Ca2+ and Mg2+, were applied to isolated nuclei in an attempt to reconstitute in vitro the digestion of …

Molecular Genetic Analysis Of Terminal Steps In Bacteriochlorophyll A Biosynthesis: Characterization Of A Rhodobacter Capsulatus Strain That Synthesizes Geranylgeranoil-Esterified Bacteriochlorophyll A, David Bollivar

Scholarship

No abstract provided.

Morphometric Analysis Of Enteric Lesions In C3h/Hen Mice Inoculated With Serpulina Hyodysenteriae Serotypes 2 And 4 With Or Without Oral Streptomycin Pretreatment, Jagannatha V. Mysore, Gerald Duhamel

School of Veterinary and Biomedical Sciences: Faculty Publications

The segmental distribution and sequential progression and the role of the indigenous bacterial flora in the development of enteric lesions associated with Serpulina hyodysenteriae infection in laboratory mice have not been defined. We examined the distribution and sequential morphometric changes in the large intestine of mice orally inoculated with S. hyodysenteriae serotypes 2 and 4. To determine the role of colonization resistance conferred by the indigenous bacterial flora, 40 female C3H/HeN mice were administered water alone or water containing 5 mg/mL streptomycin sulfate ad libitum for seven days prior to orogastric inoculation either with S. hyodysenteriae or sterile trypticase soy …

Sequence Of A Psac Gene From The Cyanobacterium Synechococcus Sp. Pcc 6301, Patricia L. Herman, Kartika Adiwilaga, John H. Golbeck, Donald P. Weeks

Department of Biochemistry: Faculty Publications

The psaC gene encodes PsaC, the apoprotein for the terminal iron-sulfur clusters, F_A and F_B, in the PSI reaction center of cyanobacteria, algae, and higher plants. PsaC functions as a membrane-bound oxidoreductase, accepting electrons from the F_x iron-sulfur cluster located on the PsaA/PsaB heterodimer and donating them to the soluble electron transfer proteins Fd and flavodoxin (reviewed in Bryant, 1992). The objective of our work is to clarify the role of PsaC in linear and cyclic electron transfer. The experimental organism is Syneckococcus sp. PCC 6301, a unicellular, freshwater cyanobacterium that is used extensively for physiological, …

Use Of Pyocin To Select A Haemophilus Ducreyi Variant Defective In Lipooligosaccharide Biosynthesis, A A. Campagnari, R Karalus, M A. Apicella, William Melaugh, A J. Lesse, B W. Gibson

Chemistry Faculty Publications

Haemophilus ducreyi, a cause of genital ulcer disease in developing countries, appears to facilitate the heterosexual transmission of the human immunodeficiency virus in Africa. Despite an increase in studies of this gram-negative human pathogen, little is known about the pathogenesis of chancroid. Our studies have shown that the lipooligosaccharides (LOS) of H. ducreyi may play an important role in ulcer formation. Monoclonal antibody and mass spectrometric analyses identified a terminal trisaccharide present on H. ducreyi LOS that is immunochemically similar to human paragloboside. This epitope is present on the LOS of Neisseria gonorrhoeae, and it may be the site of …

The Processing Pathway Of Prelamin A, Michael Sinensky, K. Fantle, M. Trujillo, T. Mclain, A. Kupfer, M. Dalton

Faculty Publications, Biological Sciences

The conversion of mammalian prelamin A to mature lamin A proceeds through the removal of 18 amino acids from the carboxyl terminus. The initial step in this processing is the isoprenylation of a CAAX box cysteine. This proteolytic event is distinctive for prelamin A among the known prenylated mammalian proteins. Since the carboxyl terminus of prelamin A is removed during maturation, it is not obvious that this protein would undergo the two reactions subsequent to prenylation observed in other CAAX box proteins-the endoproteolytic removal of the carboxyl-terminal 3 amino acids and the subsequent methylation of the now carboxyl-terminal cysteine. To …

Binding Of Matrix Attachment Regions To Lamin Polymers Involves Single-Stranded Regions And The Minor Groove., M. E. Eva Ludérus, Jan L. Den Blaauwen, Oncko J. De Smit, Duane A. Compton, Roel Van Driel

Dartmouth Scholarship

Chromatin in eukaryotic nuclei is thought to be partitioned into functional loop domains that are generated by the binding of defined DNA sequences, named MARs (matrix attachment regions), to the nuclear matrix. We have previously identified B-type lamins as MAR-binding matrix components (M. E. E. Ludérus, A. de Graaf, E. Mattia, J. L. den Blaauwen, M. A. Grande, L. de Jong, and R. van Driel, Cell 70:949-959, 1992). Here we show that A-type lamins and the structurally related proteins desmin and NuMA also specifically bind MARs in vitro. We studied the interaction between MARs and lamin polymers in molecular detail …

Evidence Of Steric Factors In The Fungitoxic Mechanism Of 8-Quinolinol And Its 2-, 3-, 4-, 5-, 6- And 7-Chloro And Bromo Analogues / Herman Gershon, Donald D. Clarke, And Muriel Gershon Department Of Chemistry, Fordham University, Bronx, Ny 10458, Usa New York Botanical Garden, Bronx, Ny 10458, Usa, Herman Gershon, Donald Dudley Clarke Phd, Muriel Gershon

Chemistry Faculty Publications

A study was made of the fungitoxicity of 2-, 3-, 4-, 5-, 6- and 7-chloro and bromo- 8-quinolinols against Aspergillus niger, A. oryzae, Myrothecium verrucaria, Trichoderma viride and Trichophyton mentagrophytes in Sabouraud dextrose broth and in Yeast Nitrogen Base supplemented with 1% D-glucose and 0.088% L-asparagine. Based on the presence or absence of synergism between pairs of substituted 8-quinolinols and reversal or nonreversal of toxicity by L-cysteine or Nacetyl- L-cysteine, the following conclusions were reached: (1) substituents on the quinoline ring change the site(s) of action of the toxicant; (2) the sites of action of the 5-, 6-, and 7-chloro-8-quinolinols …

Preparation And Fungitoxicity Of 3,6-Dichloro- And 3,6-Dibromo-8-Quinolinols / H. Gershon, D. D. Clarke, And M. Gershon Department Of Chemistry, Fordham University, Bronx, Ny 10458, Usa New York Botanical Garden, Bronx, Ny 10458, Usa, Herman Gershon, Donald Dudley Clarke Phd, Muriel Gershon

Chemistry Faculty Publications

3,6-Dichloro- and 3,6-dibromo-8-quinolinols were prepared by direct halogenation of 8-nitroquinoline by N-halosuccinimide in acetic acid or by halogenation of the corresponding 6-halo-8-nitroquinoline prepared via a Skraup reaction. The nitro group was reduced to amino and the amine was hydrolyzed to the phenol in 70% sulfuric acid at 220 °C. The fungitoxicity of 3,6-dichloro- and 3,6-dibromo-8-quinolinols, as well as intermediates in their preparation, against Aspergillus niger, Aspergillus oryzae, Myrothecium verrucaria, Trichoderma viride, and Mucor cirinelloides was determined. 3,6-dichloro-8-quinolinol is the most fungitoxic analogue of this class of compounds observed to date

Expression Of Prelamin A Confers Sensitivity Of Dna Biosynthesis To Lovastatin On F9 Teratocarcinoma Cells, Michael Sinensky, T. Mclain, K. Fantle

Faculty Publications, Biological Sciences

No abstract provided.

Nicotinic Acid Hydroxylase From Clostridium Barkeri: Electron Paramagnetic Resonance Studies Show That Selenium Is Coordinated With Molybdenum In The Catalytically Active Selenium-Dependent Enzymenicotinic Acid Hydroxylase From Clostridium Barkeri: Electron Paramagnetic Resonance Studies Show That Selenium Is Coordinated With Molybdenum In The Catalytically Active Selenium-Dependent Enzyme, Vadim Gladyshev, Sergei V. Khangulov, Thressa C. Stadtman

Vadim Gladyshev Publications

Nicotinic acid hydroxylase from Clostidum barkeri contains selenium in an unidentified form that is dissociated as a low molecular weight compound upon denaturation of the enzyme. Other cofactors of this enzyme are molybdopterin, FAD, and iron-sulfur clusters. In the current study, we show that the enzyme, as isolated, exhibits a stable Mo(V) electron paramagnetic resonance (EPR) sal ("resting" signal) and that this signal is correlated with the selenium content and nicotinate hydroxylase activity of the enzyme. Substitution of77Se for normal selenium isotope abundance results in splitting of the Mo(V) EPR signal of the native protein without affecting the iron signals …

Characteristics Of Modified Leghemoglobins Lsolated From Soybean (Glycine Max Merr.) Root Nodules, Hyung-Kyun Jun, Gautam Sarath, Jose F. Moran, Manuel Becana, Robert V. Klucas, Fred W. Wagner

Department of Biochemistry: Faculty Publications

Hemoprotein derivatives of an abundant soybean (Glycine max Merr.) root nodule leghemoglobin, Lba, were studied for their modified spectral characteristics and physical properties. Three modified hemoprotein derivatives of Lba (Lbam₁, Lbam₂, and Lbam₃) were purified by preparative isoelectric focusing. The ferric forms of these pigments were green and exhibited anomalous spedra in the visible region as compared to the Lba³⁺ forms. These modified pigments showed a hypochromic shift of 10 nm for the charge transfer absorption maximum; however, differences were not apparent in the Sdret region. Upon binding with nicotinate, the α …