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University of Massachusetts Amherst

2000

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Acetate Oxidation Coupled To Fe(Iii) Reduction In Hyperthermophilic Microorganisms, Jason M. Tor, Kazem Kashefi, Derek Lovley Dec 2000

Acetate Oxidation Coupled To Fe(Iii) Reduction In Hyperthermophilic Microorganisms, Jason M. Tor, Kazem Kashefi, Derek Lovley

Derek Lovley

No hyperthermophilic microorganisms have previously been shown to anaerobically oxidize acetate, the key extracellular intermediate in the anaerobic oxidation of organic matter. Here we report that two hyperthermophiles, Ferroglobus placidus and “Geoglobus ahangari,” grow at 85°C by oxidizing acetate to carbon dioxide, with Fe(III) serving as the electron acceptor. These results demonstrate that acetate could potentially be metabolized within the hot microbial ecosystems in which hyperthermophiles predominate, rather than diffusing to cooler environments prior to degradation as has been previously proposed.


Constant Mean Curvature Surfaces With Three Ends, Karsten Grosse-Brauckmann, Robert Kusner, John M. Sullivan Dec 2000

Constant Mean Curvature Surfaces With Three Ends, Karsten Grosse-Brauckmann, Robert Kusner, John M. Sullivan

Robert Kusner

We announce the classification of complete almost embedded surfaces of constant mean curvature, with three ends and genus zero. They are classified by triples of points on the sphere whose distances are the asymptotic necksizes of the three ends.


Temporal Changes In The Observed Relationship Between Cloud Cover And Surface Air Temperature, Bomin Sun, Pavel Ya. Groisman, Raymond S. Bradley, Frank T. Keimig Dec 2000

Temporal Changes In The Observed Relationship Between Cloud Cover And Surface Air Temperature, Bomin Sun, Pavel Ya. Groisman, Raymond S. Bradley, Frank T. Keimig

Raymond S Bradley

The relationship between cloud cover and near-surface air temperature and its decadal changes are examined using the hourly synoptic data for the past four to six decades from five regions of the Northern Hemisphere: Canada, the United States, the former Soviet Union, China, and tropical islands of the western Pacific. The authors define the normalized cloud cover–surface air temperature relationship, NOCET or dT/dCL, as a temperature anomaly with a unit (one-tenth) deviation of total cloud cover from its average value. Then mean monthly NOCET time series (night- and daytime, separately) are area-averaged and parameterized as functions of surface air humidity …


Nelig / Nebic Meeting - December 1, 2000, New England Library Instruction Group Dec 2000

Nelig / Nebic Meeting - December 1, 2000, New England Library Instruction Group

New England Library Instruction Group

NELIG / NEBIC quarterly meeting.


5. Burton Carl Anderson, Otto Vogl Dec 2000

5. Burton Carl Anderson, Otto Vogl

Emeritus Faculty Author Gallery

No abstract provided.


5. Burton Carl Anderson, Otto Vogl Dec 2000

5. Burton Carl Anderson, Otto Vogl

Otto Vogl

No abstract provided.


Mean Annual Temperature Trends And Their Vertical Structure In The Tropical Andes, Mathias Yuille, Raymond S. Bradley Dec 2000

Mean Annual Temperature Trends And Their Vertical Structure In The Tropical Andes, Mathias Yuille, Raymond S. Bradley

Raymond S Bradley

Mean annual temperature trends in the tropical Andes were determined over the last six decades ( 1939-1998), to investigate the apparent inconsistency between the observed glacier retreat and the reported slight cooling trend in the lower tropical troposphere after 1979. Our results indicate that temperature in the tropical Andes has increased by 0. 10° - 0. I l °C/decade since 1939. The rate of warming has more than tripled over the last 25 years (0.32° - 0.34 °C/decade) and the last two years of the series, associated with the 1997/98 El Nino, were the warmest of the last six decades. …


An Excursion From Enumerative Geometry To Solving Systems Of Polynomial Equations With Macaulay 2, Frank Sottile Nov 2000

An Excursion From Enumerative Geometry To Solving Systems Of Polynomial Equations With Macaulay 2, Frank Sottile

Mathematics and Statistics Department Faculty Publication Series

Solving a system of polynomial equations is a ubiquitous problem in the applications of mathematics. Until recently, it has been hopeless to find explicit solutions to such systems, and mathematics has instead developed deep and powerful theories about the solutions to polynomial equations. Enumerative Geometry is concerned with counting the number of solutions when the polynomials come from a geometric situation and Intersection Theory gives methods to accomplish the enumeration. We use Macaulay 2 to investigate some problems from enumerative geometry, illustrating some applications of symbolic computation to this important problem of solving systems of polynomial equations. Besides enumerating solutions …


6. Ichitaro Uematsu, Otto Vogl, Teiji Tsuruta, Yoshiko Uematsu Nov 2000

6. Ichitaro Uematsu, Otto Vogl, Teiji Tsuruta, Yoshiko Uematsu

Emeritus Faculty Author Gallery

No abstract provided.


6. Ichitaro Uematsu, Otto Vogl, Teiji Tsuruta, Yoshiko Uematsu Nov 2000

6. Ichitaro Uematsu, Otto Vogl, Teiji Tsuruta, Yoshiko Uematsu

Otto Vogl

No abstract provided.


The Two Micron All-Sky Survey: Removing The Infrared Foreground, John E. Gizis, Michael F. Skrutskie Oct 2000

The Two Micron All-Sky Survey: Removing The Infrared Foreground, John E. Gizis, Michael F. Skrutskie

Astronomy Department Faculty Publication Series

We introduce the properties of the Two Micron All-Sky Survey (2MASS) survey for IAU Symposium 204. 2MASS is a near-infrared survey of the entire sky characterized by high reliability and completeness. Catalogs and images for 47% of the sky are now available online. This data release has been used by Wright (2000) and Cambr´esy et al. (2000) to subtract the stellar foreground at 1.25 and 2.2 microns from COBE DIRBE data, revealing the cosmological near-infrared background.


Submillimeter Wave Astronomy Satellite Observations Of Extended Water Emission In Orion, R. L. Snell, J. E. Howe, M. L. N. Ashby, E. A. Bergin, G. Chin, Neal A. Erickson, P. F. Goldsmith, M. Harwit, S. C. Kleiner, D. G. Koch, D. A. Neufeld, B. M. Patten, R. Plume, R. Schieder, J. R. Stauffer, V. Tolls, Z. Wang, G. Winnewisser, Y. F. Zhang, G. J. Melnick Oct 2000

Submillimeter Wave Astronomy Satellite Observations Of Extended Water Emission In Orion, R. L. Snell, J. E. Howe, M. L. N. Ashby, E. A. Bergin, G. Chin, Neal A. Erickson, P. F. Goldsmith, M. Harwit, S. C. Kleiner, D. G. Koch, D. A. Neufeld, B. M. Patten, R. Plume, R. Schieder, J. R. Stauffer, V. Tolls, Z. Wang, G. Winnewisser, Y. F. Zhang, G. J. Melnick

Neal Erickson

We have used the Submillimeter Wave Astronomy Satellite to map the ground-state 1_{10}-1_{01} transition of ortho-water at 557 GHz in the Orion molecular cloud. Water emission was detected in Orion over an angular extent of about 20 arcmin, or nearly 3 pc. The water emission is relatively weak, with line widths (3-6 km s^{-1}) and V_{LSR} velocities (9-11 km s^{-1}) consistent with an origin in the cold gas of the molecular ridge. We find that the ortho-water abundance relative to H_2 in the extended gas in Orion varies between 1 and 8x10^{-8}, with an average of 3x10^{-8}. The absence of …


7. Richard S. Stein, Otto Vogl, Judith Balise Stein Oct 2000

7. Richard S. Stein, Otto Vogl, Judith Balise Stein

Emeritus Faculty Author Gallery

No abstract provided.


Volume 9, Number 4 Oct 2000

Volume 9, Number 4

SHARP News

No abstract provided.


7. Richard S. Stein, Otto Vogl, Judith Balise Stein Oct 2000

7. Richard S. Stein, Otto Vogl, Judith Balise Stein

Otto Vogl

No abstract provided.


Canaleparolina Darwiniensis, Gen. Nov., Sp. Nov., And Other Pillotinaceae Spirochetes From Insects, Andrew Wier, Jon Ashen, Lynn Margulis Sep 2000

Canaleparolina Darwiniensis, Gen. Nov., Sp. Nov., And Other Pillotinaceae Spirochetes From Insects, Andrew Wier, Jon Ashen, Lynn Margulis

Lynn Margulis (1938 - 2011)

We describe two new pillotinaceous spirochetes (Canaleparolina darwiniensis, Diplocalyx cryptotermitidis) and identify for the first time Hollandina pterotermitidisfrom both the subterranean termite Cryptotermes cavifrons and the wood-eating cockroach Cryptocercus punctulatus based on morphometric analysis of transmission electron micrographic thin sections. C. darwiniensis, gen. nov., sp. nov., limited to near Darwin, Australia, invariably is present on the surface of the treponeme-studded trichomonad Mixotricha paradoxa, a consistent inhabitant of the hindgut of healthy termite Mastotermes darwiniensis. The spirochete both attached to the surface of protists and free-swimming in the paunch (hindgut) lumen of the insect has 16 periplasmic flagella (16:32:16) and imbricated …


8. Paolo Corradini, Otto Vogl, Brigitta Griesbeck Corradini Sep 2000

8. Paolo Corradini, Otto Vogl, Brigitta Griesbeck Corradini

Emeritus Faculty Author Gallery

No abstract provided.


8. Paolo Corradini, Otto Vogl, Brigitta Griesbeck Corradini Sep 2000

8. Paolo Corradini, Otto Vogl, Brigitta Griesbeck Corradini

Otto Vogl

No abstract provided.


The Distribution Of Water Emission In M17sw, R. L. Snell, J. E. Howe, M. L. N. Ashby, E. A. Bergin, G. Chin, Neal A. Erickson, P. F. Goldsmith, M. Harwit, S. C. Kleiner, D. G. Koch, D. A. Neufeld, B. M. Patten, R. Plume, R. Schieder, J. R. Stauffer, V. Tolls, Z. Wang, G. Winnewisser, Y. F. Zhang, G. J. Melnick Aug 2000

The Distribution Of Water Emission In M17sw, R. L. Snell, J. E. Howe, M. L. N. Ashby, E. A. Bergin, G. Chin, Neal A. Erickson, P. F. Goldsmith, M. Harwit, S. C. Kleiner, D. G. Koch, D. A. Neufeld, B. M. Patten, R. Plume, R. Schieder, J. R. Stauffer, V. Tolls, Z. Wang, G. Winnewisser, Y. F. Zhang, G. J. Melnick

Neal Erickson

We present a 17-point map of the M17SW cloud core in the 1_{10}-1_{01} transition of ortho-water at 557 GHz obtained with the Submillimeter Wave Astronomy Satellite. Water emission was detected in 11 of the 17 observed positions. The line widths of the water emission vary between 4 and 9 km s^{-1}, and are similar to other emission lines that arise in the M17SW core. A direct comparison is made between the spatial extent of the water emission and the ^{13}CO J = 5\to4 emission; the good agreement suggests that the water emission arises in the same warm, dense gas as …


Water Abundance In Molecular Cloud Cores, R. L. Snell, J. E. Howe, M. L. N. Ashby, E. A. Bergin, G. Chin, Neal A. Erickson, P. F. Goldsmith, M. Harwit, S. C. Kleiner, D. G. Koch, D. A. Neufeld, B. M. Patten, R. Plume, R. Schieder, J. R. Stauffer, V. Tolls, Z. Wang, G. Winnewisser, Y. F. Zhang, G. J. Melnick Aug 2000

Water Abundance In Molecular Cloud Cores, R. L. Snell, J. E. Howe, M. L. N. Ashby, E. A. Bergin, G. Chin, Neal A. Erickson, P. F. Goldsmith, M. Harwit, S. C. Kleiner, D. G. Koch, D. A. Neufeld, B. M. Patten, R. Plume, R. Schieder, J. R. Stauffer, V. Tolls, Z. Wang, G. Winnewisser, Y. F. Zhang, G. J. Melnick

Neal Erickson

We present Submillimeter Wave Astronomy Satellite (SWAS) observations of the 1_{10}-1_{01} transition of ortho-water at 557 GHz toward 12 molecular cloud cores. The water emission was detected in NGC 7538, Rho Oph A, NGC 2024, CRL 2591, W3, W3(OH), Mon R2, and W33, and was not detected in TMC-1, L134N, and B335. We also present a small map of the water emission in S140. Observations of the H_2^{18}O line were obtained toward S140 and NGC 7538, but no emission was detected. The abundance of ortho-water relative to H_2 in the giant molecular cloud cores was found to vary between 6x10^{-10} …


Nebic Meeting - August 18, 2000, New England Library Instruction Group Aug 2000

Nebic Meeting - August 18, 2000, New England Library Instruction Group

New England Library Instruction Group

NEBIC quarterly meeting.


9. Oskar Friedrich Olaj, Otto Vogl Aug 2000

9. Oskar Friedrich Olaj, Otto Vogl

Emeritus Faculty Author Gallery

No abstract provided.


A Model Of The Implementation Of Quality Management Systems For Credence Attributes, Corinna Noelke, Julie Caswell Aug 2000

A Model Of The Implementation Of Quality Management Systems For Credence Attributes, Corinna Noelke, Julie Caswell

Julie Caswell

We develop a model of the impact of food quality management systems (QMS) on competitiveness and markets. QMS seek to control the quality of a product as determined by the array of individual attributes it possesses. To date only a few studies have attempted to better understand the effect of the introduction of quality management systems. No model has been introduced which captures the interactions within the supply chain and at the interface with consumers when these systems are introduced.


Dynamics Of Lattice Kinks, Panos Kevrekidis, M. I. Weinstein Aug 2000

Dynamics Of Lattice Kinks, Panos Kevrekidis, M. I. Weinstein

Panos Kevrekidis

In this paper we consider two models of soliton dynamics (the sine Gordon and the \phi^4 equations) on a 1-dimensional lattice. We are interested in particular in the behavior of their kink-like solutions inside the Peierls- Nabarro barrier and its variation as a function of the discreteness parameter. We find explicitly the asymptotic states of the system for any value of the discreteness parameter and the rates of decay of the initial data to these asymptotic states. We show that genuinely periodic solutions are possible and we identify the regimes of the discreteness parameter for which they are expected to …


9. Oskar Friedrich Olaj, Otto Vogl Aug 2000

9. Oskar Friedrich Olaj, Otto Vogl

Otto Vogl

No abstract provided.


Outdoor Allergens, H A. Burge, Christine A. Rogers Aug 2000

Outdoor Allergens, H A. Burge, Christine A. Rogers

Christine A. Rogers

Outdoor allergens are an important part of the exposures that lead to allergic disease. Understanding the role of outdoor allergens requires a knowledge of the nature of outdoor allergen-bearing particles, the distributions of their source, and the nature of the aerosols (particle types, sizes, dynamics of concentrations). Primary sources for outdoor allergens include vascular plants (pollen, fern spores, soy dust), and fungi (spores, hyphae). Nonvascular plants, algae, and arthropods contribute small numbers of allergen-bearing particles. Particles are released from sources into the air by wind, rain, mechanical disturbance, or active discharge mechanisms. Once airborne, they follow the physical laws that …


10. Dietrich Braun, Otto Vogl Jul 2000

10. Dietrich Braun, Otto Vogl

Emeritus Faculty Author Gallery

No abstract provided.


Volume 9, Number 3 Jul 2000

Volume 9, Number 3

SHARP News

No abstract provided.


Appendix B: The Structure Of A World View (Kluback & Weinbaum 1957, 25-27), J.L. Benson Jul 2000

Appendix B: The Structure Of A World View (Kluback & Weinbaum 1957, 25-27), J.L. Benson

Greek Sculpture and the Four Elements

No abstract provided.


Epilogue: On Philosophers And Artists, J.L. Benson Jul 2000

Epilogue: On Philosophers And Artists, J.L. Benson

Greek Sculpture and the Four Elements

No abstract provided.