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Optimal Algorithms For Multipacket Routing Problems On Rings, Fillia Makedon, Antonios Symvonis Dec 1991

Optimal Algorithms For Multipacket Routing Problems On Rings, Fillia Makedon, Antonios Symvonis

Computer Science Technical Reports

We study multipacket routing problems. We divide the multipacket routing problem into two classes, namely, distance limited and bisection limited routing problems. Then, we concentrate on rings of processors. We prove a new lower bound of 2n/ 3 routing steps for the case of distance limited routing problems. We also give an algorithm that tightens this lower bound. For bisection limited problems the lower bound is kn/ 4,k >2, where k is the number of packets per processor. The trivial algorithm needs in the worst case k | n /2| steps to terminate. An algorithm that completes the routing in …


The Landmark Citation Method: Analysis Of A Citation Pattern As A Collection Assessment Method, Catherine B. Soehner, S Tanner Wray, Daniel T. Richards Dec 1991

The Landmark Citation Method: Analysis Of A Citation Pattern As A Collection Assessment Method, Catherine B. Soehner, S Tanner Wray, Daniel T. Richards

Dartmouth Scholarship

The landmark citation method is a new collection assessment method based on the citation record of a single landmark article. This citation record is developed by identifying sources which cite the landmark article. A bibliography, extracted from the citation record, is then used to complete an assessment of the collection. This method was developed and used to assess the biotechnology collection of the National Library of Medicine. The information gained from this study, in addition to demonstrating the technique, also provided insight into the evolution of the biotechnology literature.


Practical Prefetching Techniques For Parallel File Systems, David Kotz, Carla Schlatter Ellis Dec 1991

Practical Prefetching Techniques For Parallel File Systems, David Kotz, Carla Schlatter Ellis

Dartmouth Scholarship

Parallel disk subsystems have been proposed as one way to close the gap between processor and disk speeds. In a previous paper we showed that prefetching and caching have the potential to deliver the performance benefits of parallel file systems to parallel applications. In this paper we describe experiments with practical prefetching policies, and show that prefetching can be implemented efficiently even for the more complex parallel file access patterns. We test these policies across a range of architectural parameters.


The Ability Of Simian Virus 40 Large T Antigen To Immortalize Primary Mouse Embryo Fibroblasts Cosegregates With Its Ability To Bind To P53., Jiyue Y. Zhu, Marina Abate, Philip W. Rice, Charles N. Cole Dec 1991

The Ability Of Simian Virus 40 Large T Antigen To Immortalize Primary Mouse Embryo Fibroblasts Cosegregates With Its Ability To Bind To P53., Jiyue Y. Zhu, Marina Abate, Philip W. Rice, Charles N. Cole

Dartmouth Scholarship

The large T antigen encoded by simian virus 40 (SV40) plays essential roles in the infection of permissive cells, leading to production of progeny virions, and in the infection of nonpermissive cells, leading to malignant transformation. Primary mouse embryo fibroblasts (MEFs) are nonpermissive for SV40, and infection by wild-type SV40 leads to immortalization and transformation of a small percentage of infected cells. We examined the ability of an extensive set of mutants whose lesions affect SV40 large T antigen to immortalize MEFs. We found that immortalization activity was retained by all mutants whose lesions are located upstream of codon 346. …


Caching And Writeback Policies In Parallel File Systems, David Kotz, Carla Schlatter Ellis Dec 1991

Caching And Writeback Policies In Parallel File Systems, David Kotz, Carla Schlatter Ellis

Dartmouth Scholarship

Improvements in the processing speed of multiprocessors are outpacing improvements in the speed of disk hardware. Parallel disk I/O subsystems have been proposed as one way to close the gap between processor and disk speeds. Such parallel disk systems require parallel file system software to avoid performance-limiting bottlenecks. We discuss cache management techniques that can be used in a parallel file system implementation. We examine several writeback policies, and give results of experiments that test their performance.


A Polymerase Chain Reaction-Based Method To Detect Cisplatin Adducts In Specific Genes, M M. Jennerwein, A Eastman Nov 1991

A Polymerase Chain Reaction-Based Method To Detect Cisplatin Adducts In Specific Genes, M M. Jennerwein, A Eastman

Dartmouth Scholarship

Every bulky lesion in DNA can potentially inhibit the Taq DNA polymerase and thereby decrease the amplification produced in the polymerase chain reaction. We investigated the feasibility of using this inhibition to quantify DNA lesions produced by the anticancer drug cisplatin. Products were detected by electrophoresis followed by ethidium bromide staining. Quantitation was obtained by including [32P]dCTP in the amplification reaction and subsequently assessing the incorporated radioactivity. Hamster genomic DNA was platinated in vitro to defined levels and amplified with primers that produce either a 150, 750 or 2,000 base pair fragment. The degree of inhibition of PCR …


Effects Of Replication On The Duration Of Failure In Distributed Databases, Donald B. Johnson, Larry Raab Nov 1991

Effects Of Replication On The Duration Of Failure In Distributed Databases, Donald B. Johnson, Larry Raab

Computer Science Technical Reports

Replicating data objects has been suggested as a means of increasing the performance of a distributed database system in a network subject to link and site failures. Since a network may partition as a consequence of such failures, a data object may become unavailable from a given site for some period of time. In this paper we study duration failure, which we define as the length of time, once the object becomes unavailable from a particular site, that the object remains unavailable. We show that, for networks composed of highly-reliable components, replication does not substantially reduce the duration of failure. …


Availability Issues In Data Replication In Distributed Database, Donald B. Johnson, Larry Raab Nov 1991

Availability Issues In Data Replication In Distributed Database, Donald B. Johnson, Larry Raab

Computer Science Technical Reports

Replication of data at more than one site in a distributed database has been reported to increase the availability in data in systems where sites and links are subject to failure. We have shown in results summarized in this paper that in many interesting cases the advantage is slight. A well-placed single copy is available to transactions almost as much of the time as is correct replicated data no matter how ingeniously it is managed. We explain these findings in terms of the behavior of the partitions that form in networks where components fail. We also show that known and …


Fc Receptors For Igg (Fc Gamma Rs) On Human Monocytes And Macrophages Are Not Infectivity Receptors For Human Immunodeficiency Virus Type 1 (Hiv-1): Studies Using Bispecific Antibodies To Target Hiv-1 To Various Myeloid Cell Surface Molecules, Including The Fc Gamma R., R I. Connor, N B. Dinces, A L. Howell, J L. Romet-Lemonne, J L. Pasquali, M W. Fanger Nov 1991

Fc Receptors For Igg (Fc Gamma Rs) On Human Monocytes And Macrophages Are Not Infectivity Receptors For Human Immunodeficiency Virus Type 1 (Hiv-1): Studies Using Bispecific Antibodies To Target Hiv-1 To Various Myeloid Cell Surface Molecules, Including The Fc Gamma R., R I. Connor, N B. Dinces, A L. Howell, J L. Romet-Lemonne, J L. Pasquali, M W. Fanger

Dartmouth Scholarship

Fc gamma Rs (Fc gamma RI, Fc gamma RII, and Fc gamma RIII) are highly expressed on human mononuclear phagocytes and function in the clearance of immune complexes and opsonized pathogens. We have examined the role of Fc gamma R in mediating antibody-dependent clearance of HIV-1 by human monocytes and monocyte-derived macrophages by using bispecific antibodies (BsAbs) to independently target the virus to Fc gamma RI, Fc gamma RII, or Fc gamma RIII. Virus production was markedly reduced in monocytes cultured with strain HIV-1IIIB opsonized with BsAbs that target the virus to either Fc gamma RI or Fc gamma RII …


Complexity Of Network Reliability And Optimal Database Placement Problems, Donald B. Johnson, Larry Raab Oct 1991

Complexity Of Network Reliability And Optimal Database Placement Problems, Donald B. Johnson, Larry Raab

Computer Science Technical Reports

A fundamental problem of distributed database design in an existing network where components can fail is finding an optimal location at which to place the database in a centralized system or copies of each data item in a decentralized or replicated system. In this paper it is proved for the first time exactly how hard this placement problem is under the measure of data availability. Specifically, we show that the optimal placement problem for availability is #P- complete, a measure of intractability at least as severe as NP-completeness. Given the anticipated computational difficulty of finding an exact solution, we go …


Ilona: An Advanced Cai Tutorial System For The Fundamentals Of Logic, Otto Mayer, Graham E. Oberem, Fillia Makedon Sep 1991

Ilona: An Advanced Cai Tutorial System For The Fundamentals Of Logic, Otto Mayer, Graham E. Oberem, Fillia Makedon

Computer Science Technical Reports

An advanced tutorial system for teaching the fundamentals of logic has been developed to run on UNIX work stations and commonly available micro-computers. An important part of this tutorial is the intelligent problem solving environment which allows students to practise wiriting logical sentences in mathematical notation. A natural language system for intelligent logic narrative analysis (ILONA) allows students to type in their own logical sentences in plain English and then have the computer check their working when they write these in mathematical form. ILONA is an intelligent tutoring system which allows students a great deal of initiative in problem solving …


Physiological Basis For Differential Sensitivities Of Plant Species To Protoporphyrinogen Oxidase-Inhibiting Herbicides, Timothy D. Sherman, José M. Becerril, Hiroshi Matsumoto, Mary V. Duke, Judy M. Jacobs, Nicholas J. Jacobs, Stephen O. Duke Sep 1991

Physiological Basis For Differential Sensitivities Of Plant Species To Protoporphyrinogen Oxidase-Inhibiting Herbicides, Timothy D. Sherman, José M. Becerril, Hiroshi Matsumoto, Mary V. Duke, Judy M. Jacobs, Nicholas J. Jacobs, Stephen O. Duke

Dartmouth Scholarship

With a leaf disc assay, 11 species were tested for effects of the herbicide acifluorfen on porphyrin accumulation in darkness and subsequent electrolyte leakage and photobleaching of chlorophyll after exposure to light. Protoporphyrin IX (Proto IX) was the only porphyrin that was substantially increased by the herbicide in any of the species. However, there was a wide range in the amount of Proto IX accumulation caused by 0.1 millimolar acifluorfen between species. Within species, there was a reduced effect of the herbicide in older tissues. Therefore, direct quantitative comparisons between species are difficult. Nevertheless, when data from different species and …


Translocation Of The Glucose Transporter Glut4 In Cardiac Myocytes Of The Rat., Jan W. Slot, Hans J. Geuze, Sander Gigengack, David E. James, Gustav E. Lienhard Sep 1991

Translocation Of The Glucose Transporter Glut4 In Cardiac Myocytes Of The Rat., Jan W. Slot, Hans J. Geuze, Sander Gigengack, David E. James, Gustav E. Lienhard

Dartmouth Scholarship

The insulin-regulated glucose transporter GLUT4 was immunolocalized in rat cardiac muscle under conditions of basal and stimulated glucose uptake, achieved by fasting and a combined exercise/insulin stimulus, respectively. In basal myocytes there was very little (less than 1%) GLUT4 in the different domains of the plasma membrane (sarcolemma, intercalated disk, and transverse tubular system). GLUT4 was localized in small tubulo-vesicular elements that occur predominantly near the sarcolemma and the transverse tubular system and in the trans-Golgi region. Upon stimulation approximately 42% of GLUT4 was found in the plasma membrane. Each domain of the plasma membrane contributed equally to this effect. …


The Submembrane Machinery For Nicotinic Acetylcholine Receptor Clustering, S. C. Froehner Jul 1991

The Submembrane Machinery For Nicotinic Acetylcholine Receptor Clustering, S. C. Froehner

Dartmouth Scholarship

No abstract provided.


Participation In Heterogeneous And Homogeneous Groups : A Theoretical Integration, M Fişek, Joseph Berger, Robert Norman Jul 1991

Participation In Heterogeneous And Homogeneous Groups : A Theoretical Integration, M Fişek, Joseph Berger, Robert Norman

Dartmouth Scholarship

This article presents a theoretical formulation that integrates, within the framework of expectation states theory, theories of the emergence of power-and-prestige orders in status-heterogeneous and homogeneous task-oriented groups. A model based on this theoretical formulation is constructed and used for predicting participation rates in open interaction settings. The article explores the fit of the model to data from both status-heterogeneous and status- homogeneous groups.


Mapping The Transcriptional Transactivation Function Of Simian Virus 40 Large T Antigen., Jiyue Y. Zhu, Philip W. Rice, Michele Chamberlain, Charles N. Cole Jun 1991

Mapping The Transcriptional Transactivation Function Of Simian Virus 40 Large T Antigen., Jiyue Y. Zhu, Philip W. Rice, Michele Chamberlain, Charles N. Cole

Dartmouth Scholarship

T antigen is able to transactivate gene expression from the simian virus 40 (SV40) late promoter and from several other viral and cellular promoters. Neither the mechanisms of transactivation by T antigen nor the regions of T antigen required for this activity have been determined. To address the latter point, we have measured the ability of a set of SV40 large T antigen mutants to stimulate gene expression in CV-1 monkey kidney cells from the SV40 late promoter and Rous sarcoma virus (RSV) long terminal repeat (LTR) promoter. Transactivation, although reduced, was retained by an N-terminal 138-amino-acid fragment of T …


Effect Of Delays In Processing On The Survival Of Mycobacterium Avium-M. Intracellulare In The Isolator Blood Culture System., C. Fordham Von Reyn, Stephen Hennigan, Sandra Niemczyk, Nicholas J. Jacobs Jun 1991

Effect Of Delays In Processing On The Survival Of Mycobacterium Avium-M. Intracellulare In The Isolator Blood Culture System., C. Fordham Von Reyn, Stephen Hennigan, Sandra Niemczyk, Nicholas J. Jacobs

Dartmouth Scholarship

Concentrations of Mycobacterium avium-M. intracellulare ranging from 10(-1) to 10(3) CFU/ml were added to blood, placed in Isolator tubes, and held at room temperature for intervals ranging from 4 h to 56 days before being processed (centrifugation and culture on Middlebrook 7H10 agar). At all concentrations tested, M. avium-M. intracellulare was recovered after hold times ranging from 4 h to 7 days; the number of final CFU actually increased progressively for hold times of 8 h or more. Hold times of up to 7 days did not increase the time from processing to the first appearance of visible colonies. At …


Selective Decay And Coherent Vortices In Two-Dimensional Incompressible Turbulence, William H. Matthaeus, W. Troy Stribling, Daniel Martinez, Sean Oughton, David Montgomery May 1991

Selective Decay And Coherent Vortices In Two-Dimensional Incompressible Turbulence, William H. Matthaeus, W. Troy Stribling, Daniel Martinez, Sean Oughton, David Montgomery

Dartmouth Scholarship

Numerical solution of two-dimensional incompressible hydrodynamics shows that states of a near-minimal ratio of enstrophy to energy can be attained in times short compared with the flow decay time, confirming the simplest turbulent selective decay conjecture, and suggesting that coherent vortex structures do not terminate nonlinear processes. After all possible vortex mergers occur, the vorticity attains a particlelike character, suggested by the late-time similarity of the streamlines to Ewald potential contours.


The Fracture Of Ice On Scales Large And Small: Arctic Leads And Wing Cracks, E. M. Schulson, W. D. Hibler May 1991

The Fracture Of Ice On Scales Large And Small: Arctic Leads And Wing Cracks, E. M. Schulson, W. D. Hibler

Dartmouth Scholarship

From observations and calculations of crack patterns in ice, it is suggested that a similar mechanism may account for cracking over a wide range of scales.


Evidence For Attenuation Of Myo-Inositol Uptake, Phosphoinositide Turnover And Inositol Phosphate Production In Aortic Vasculature Of Rats During Pregnancy, Kirk P. Conrad, Susan A. Barrera, Peter A. Friedman, Vicki M. Schmidt May 1991

Evidence For Attenuation Of Myo-Inositol Uptake, Phosphoinositide Turnover And Inositol Phosphate Production In Aortic Vasculature Of Rats During Pregnancy, Kirk P. Conrad, Susan A. Barrera, Peter A. Friedman, Vicki M. Schmidt

Dartmouth Scholarship

We postulated that vascular phosphoinositide metabolism is attenuated during pregnancy, and thereby could contribute to maternal vasodilation and reduced vascular reactivity. The basal rate of incorporation of [3H]myo-inositol and [3H]glycerol into phosphoinositides of aortae from pregnant rats in vitro was significantly reduced, when compared with vessels from virgin animals. After injection of [3H]myo-inositol intravenously into chronically instrumented conscious pregnant and virgin rats, the incorporation of the label by phosphatidylinositol was 66 +/- 4% less in aortae of gravid versus virgin animals (P less than 0.001), despite comparable plasma concentrations of radioactivity. Fold stimulation of total [3H]inositol phosphates by arginine vasopressin, …


Interleukin-2-Triggered Raf-1 Expression, Phosphorylation, And Associated Kinase Activity Increase Through G1 And S In Cd3-Stimulated Primary Human T Cells., Antanina Zmuidzinas, Harvey J. Mamon, Thomas M. Roberts, Kendall A. Smith May 1991

Interleukin-2-Triggered Raf-1 Expression, Phosphorylation, And Associated Kinase Activity Increase Through G1 And S In Cd3-Stimulated Primary Human T Cells., Antanina Zmuidzinas, Harvey J. Mamon, Thomas M. Roberts, Kendall A. Smith

Dartmouth Scholarship

To gain further insight into the role of Raf-1 in normal cell growth, c-raf-1 mRNA expression, Raf-1 protein production, and Raf-1-associated kinase activity in normal human T cells were analyzed. In contrast to the constitutive expression of Raf-1 in continuously proliferating cell lines, c-raf-1 mRNA and Raf-1 protein levels were barely detectable in freshly isolated G0 T lymphocytes. Previous work with fibroblasts has suggested that Raf-1 plays a signaling role in the G0-G1 phase transition. In T cells, triggering via the T-cell antigen receptor (TCR)-CD3 complex (TCR/CD3) resulted in an approximately fourfold increase in c-raf-1 mRNA. In addition, the promotion …


Reaction Of Chromium(Vi) With Glutathione Or With Hydrogen Peroxide: Identification Of Reactive Intermediates And Their Role In Chromium(Vi)-Induced Dna Damage, J Aiyar, H Berkovits, R Floyd, K Wetterhahn May 1991

Reaction Of Chromium(Vi) With Glutathione Or With Hydrogen Peroxide: Identification Of Reactive Intermediates And Their Role In Chromium(Vi)-Induced Dna Damage, J Aiyar, H Berkovits, R Floyd, K Wetterhahn

Dartmouth Scholarship

The types of reactive intermediates generated upon reduction of chromium(VI) by glutathione or hydrogen peroxide and the resulting DNA damage have been determined. In vitro, reaction of chromium(VI) with glutathione led to formation of two chromium(V) complexes and the glutathione thiyl radical. When chromium(VI) was reacted with DNA in the presence of glutathione, chromium-DNA adducts were obtained, with no DNA strand breakage. The level of chromium-DNA adduct formation correlated with chromium(V) formation. Reaction of chromium(VI) with hydrogen peroxide led to formation of hydroxyl radical. No chromium(V) was detectable at 24 degrees C (297 K); however, low levels of the tetraperoxochromium(V) …


The Thermal Response Of Downhill Skis, S. C. Colbeck, G. C. Warren Apr 1991

The Thermal Response Of Downhill Skis, S. C. Colbeck, G. C. Warren

Dartmouth Scholarship

No abstract provided.


Prefetching And Caching Techniques In File Systems For Mimd Multiprocessors, David F. Kotz Apr 1991

Prefetching And Caching Techniques In File Systems For Mimd Multiprocessors, David F. Kotz

Dartmouth Scholarship

The increasing speed of the most powerful computers, especially multiprocessors, makes it difficult to provide sufficient I/O bandwidth to keep them running at full speed for the largest problems. Trends show that the difference in the speed of disk hardware and the speed of processors is increasing, with I/O severely limiting the performance of otherwise fast machines. This widening access-time gap is known as the “I/O bottleneck crisis.” One solution to the crisis, suggested by many researchers, is to use many disks in parallel to increase the overall bandwidth. \par This dissertation studies some of the file system issues needed …


Ecdysterone Regulatory Elements Function As Both Transcriptional Activators And Repressors., Leonard Dobens, Karen Rudolph, Edward M. Berger Apr 1991

Ecdysterone Regulatory Elements Function As Both Transcriptional Activators And Repressors., Leonard Dobens, Karen Rudolph, Edward M. Berger

Dartmouth Scholarship

A synthetic, 23-bp ecdysterone regulatory element (EcRE), derived from the upstream region of the Drosophila melanogaster hsp27 gene, was inserted adjacent to the herpes simplex virus thymidine kinase promoter fused to a bacterial gene for chloramphenicol acetyltransferase (CAT). Hybrid constructs were transfected into Drosophila S3 cells and assayed for ecdysterone-inducible CAT expression. In the absence of ecdysterone a tandem pair of EcREs repressed the high constitutive level of CAT activity found after transfection with the parent reporter plasmid alone. After hormone addition very high levels of CAT activity were observed. Insertion of the EcRE pair 3' of the CAT gene …


Multiphoton Ionization Of Nitrobenzene In Non-Aqueous Solutions: Characterization Of The Cation And Ion-Molecule Chemistry, G. Siuzdak, J. J. Belbruno Mar 1991

Multiphoton Ionization Of Nitrobenzene In Non-Aqueous Solutions: Characterization Of The Cation And Ion-Molecule Chemistry, G. Siuzdak, J. J. Belbruno

Dartmouth Scholarship

The phenoxy cation has been generated in polar and nonpolar solutions by multiphoton ionization of nitrobenzene using nanosecond pulses of 266 nm and 355 nm light. The ions have been characterized by pulsed conductivity (ion mobility) measurements and transient absorption spectroscopy. The involvement of the phenoxy ion in ion-molecule chemistry with either neutral solute or solvent molecules has also been observed and the photochemical products and quantum yields of the ion-molecule products are presented and compared with the neutral photochemistry results.


Acquired Cisplatin Resistance In Human Ovarian Cancer Cells Is Associated With Enhanced Repair Of Cisplatin-Dna Lesions And Reduced Drug Accumulation., Ricardo J. Parker, Alan Eastman, Frieda Bostick-Bruton, Eddie Reed Mar 1991

Acquired Cisplatin Resistance In Human Ovarian Cancer Cells Is Associated With Enhanced Repair Of Cisplatin-Dna Lesions And Reduced Drug Accumulation., Ricardo J. Parker, Alan Eastman, Frieda Bostick-Bruton, Eddie Reed

Dartmouth Scholarship

Studies were undertaken to investigate acquired resistance to cisplatin in human ovarian cancer cells. The cell lines A2780 and A2780/CP70 were studied to assess their respective characteristics of drug accumulation and efflux, cytosolic inactivation of drug, and DNA repair. All experiments were performed using 1-h drug exposures. The A2780/CP70 cell line was 13-fold more resistant to cisplatin than A2780 cells. When studied at their respective IC50 doses, drug accumulation rates were similar for the two cell lines. However, the resistant cell line was twofold more efficient at effluxing drug, which was associated with reduced total drug accumulation for equivalent micromolar …


Moore Cohomology, Principal Bundles, And Actions Of Groups On C*-Algebras, Ian Raeburn, Dana P. Williams Feb 1991

Moore Cohomology, Principal Bundles, And Actions Of Groups On C*-Algebras, Ian Raeburn, Dana P. Williams

Dartmouth Scholarship

In recent years both topological and algebraic invariants have been associated to group actions on C*-algebras. Principal bundles have been used to describe the topological structure of the spectrum of crossed products [18, 19], and as a result we now know that crossed products of even the very nicest non-commutative algebras can be substantially more complicated than those of commutative algebras [19, 5]. The algebraic approach involves group cohomological invariants, and exploits the associated machinery to classify group actions on C*-algebras; this originated in [2], and has been particularly successful for actions of R and tori ([19; Section 4], [21]). …


Uv Observations Of The Cool Dbqa5 White Dwarf Lds 678a - Limits On The Atmospheric Composition, Pressure Shift, And Gravitational Redshift Derived From C I 2479, Terry D. Oswalt, Edward M. Sion, Gordon Hammond, Gerard Vauclair, James W. Liebert, Gary Wegner Jan 1991

Uv Observations Of The Cool Dbqa5 White Dwarf Lds 678a - Limits On The Atmospheric Composition, Pressure Shift, And Gravitational Redshift Derived From C I 2479, Terry D. Oswalt, Edward M. Sion, Gordon Hammond, Gerard Vauclair, James W. Liebert, Gary Wegner

Dartmouth Scholarship

A high-resolution ultraviolet spectrum of the helium-rich degenerate LDS 678A, obtained with the International Ultraviolet Explorer (IUE) satellite, is presented. LDS 678A is the coolest metallic line degenerate (DQ or DZ) yet observed with the IUE echelle. These observations provide a detailed line profile of the strong C I 2479 absorption line and equivalent width W2479 = 2.35 + or - 0.06 A from which theoretical profile fits yield a carbon abundance of log C/He = (-6.7 + or- 0.2). The presence of carbon in a He-rich atmosphere lends credence to the notion that LDS 678A is a transitional case …


Interleukin-1 Or Phorbol Induction Of The Stromelysin Promoter Requires An Element That Cooperates With Ap-1., Karen Sirum-Connolly, Constance E. Brinckerhoff Jan 1991

Interleukin-1 Or Phorbol Induction Of The Stromelysin Promoter Requires An Element That Cooperates With Ap-1., Karen Sirum-Connolly, Constance E. Brinckerhoff

Dartmouth Scholarship

Interieukin-1, a mediator of inflammation, or tumor promoting phorbol esters induce transcription of stromelysin, a metalloproteinase that degrades extracellular matrix molecules and that is overexpressed in diseases such as rheumatoid arthritis. Sequences required for induction of transcription of the human stromelysin promoter are contained on a 46 base pair fragment. This fragment contains a sequence with a high degree of similarity to the binding site for the transcription factor activator protein-1 (AP-1) and indeed, the AP-1 sequence of this fragment is necessary but not sufficient for the maximal response to phorbol 12-myristate 13-acetate (phorbol) or interleukin-1. Maximal induction requires functional …