Digital Commons Network^™

Trajectory Model Validation Using Newly Developed Altitude-Controlled Balloons During The International Consortium For Atmospheric Research On Transport And Transformations 2004 Campaign, Emily E. Riddle, Paul B. Voss, Andreas Stohl, Daniel Holcomb, Darren Maczka, K. Washburn, Robert W. Talbot

Engineering: Faculty Publications

During the summer of 2004, five altitude-controlled tracking balloons were flown as part of the International Consortium for Atmospheric Research on Transport and Transformations (ICARTT) campaign. These Controlled Meteorological (CMET) balloons, newly developed at the University of Massachusetts, are notable for their light weight (∼1 kg mass), efficient altitude control, case of launch, long-duration flight capability, and ability to perform repeated quasi-Lagrangian soundings. The balloons were embedded in urban plumes from New York and Boston which they tracked over New England, eastern Canada, and the Atlantic Ocean while maintaining a nearly constant altitude. The flights ranged from 10 to 111 …

Sometimes Close Is Good Enough: The Value Of Nearby Environmental Amenities, Lucie Schmidt, Paul N. Courant

Economics: Faculty Publications

An extensive empirical literature exists, showing that variations in region-specific amenities can account for persistent differences in real wages across regions. However, this literature has considered only amenities in the same location as the household. This paper argues that environmental amenities at some distance from but accessible to urban areas may lead to negative compensating wage differentials. We use a general equilibrium framework and data from the 1995 Current Population Survey to calculate implicit amenity prices based on measures of distance to environmental amenities. Our results suggest that amenities outside the metropolitan area do generate compensating wage differentials, as workers …

Kishida Toshiko And The Rise Of The Female Speaker In Meiji Japan., Marnie S. Anderson

History: Faculty Publications

No abstract provided.

Book Review Essay, Richard Lim

History: Faculty Publications

Book reviews of:

The Ascension of Authorship: Attribution and Canon Formation in Jewish, Hellenistic and Christian Traditions. By Jed Wyrick. Harvard Studies in Comparative Literature 49. Cambridge, Mass.: Harvard University Press, 2004. xviii + 509 pp.

An Ecstasy of Folly: Prophecy and Authority in Early Christianity. By Laura Nasrallah. Harvard Theological Studies 52. Cambridge, Mass.: Harvard University Press, 2004. xii + 225 pp.

Writing and Holiness: The Practice of Authorship in the Early Christian East. By Derek Krueger. Divinations: Rereading Ancient Religion. Philadelphia: University of Pennsylvania Press, 2004. 312 pp.

Ahlfors Type Estimates For Perimeter Measures In Carnot-Carathéodory Spaces, Luca Capogna, Nicola Garofalo

Mathematics Sciences: Faculty Publications

We study the relationship between the geometry of hypersurfaces in a Carnot-Carathéodory (CC) space and the Ahlfors regularity of the corresponding perimeter measure. To this end we establish comparison theorems for perimeter estimates between an hypersurface and its tangent space, and between a CC geometry and its "tangent" Carnot group structure.

Linear Conditions Imposed On Flag Varieties, Julianna S. Tymoczko

Mathematics Sciences: Faculty Publications

We study subvarieties of the flag variety called Hessenberg varieties, defined by certain linear conditions. These subvarieties arise naturally in applications including geometric representation theory, number theory, and numerical analysis. We describe completely the homology of Hessenberg varieties over GLn(ℂ) and show that they have no odd-dimensional homology. We provide an explicit geometric construction which partitions each Hessenberg variety into pieces homeomorphic to affine space. We characterize these affine pieces by fillings of Young tableaux and show that the dimension of the affine piece can be computed by combinatorial rules generalizing the Eulerian numbers. We give an equivalent formulation of …

Conformality And Q-Harmonicity In Carnot Groups, Luca Capogna, Michael Cowling

Mathematics Sciences: Faculty Publications

We show that if f is a 1-quasiconformal map defined on an open subset of a Carnot group G, then composition with f preserves Q-harmonic functions. We combine this with a regularity theorem for Q-harmonic functions and an algebraic regularity theorem for maps between Carnot groups to show that f is smooth. We give some applications to the study of rigidity.

Local Energy Decay For Solutions Of Multi-Dimensional Isotropic Symmetric Hyperbolic Systems, Thomas C. Sideris, Becca Thomases

Mathematics Sciences: Faculty Publications

The local decay of energy is established for solutions to certain linear, multidimensional symmetric hyperbolic systems, with constraints. The key assumptions are isotropy and nondegeneracy of the associated symbols. Examples are given, including Maxwell's equations and linearized elasticity. Such estimates prove useful in treating nonlinear perturbations.

Sexual Interactions: Why We Should Talk About Sex In Hci, Johanna Brewer, Joseph Jofish Kaye, Amanda Williams, Susan Wyche

Computer Science: Faculty Publications

Within the CHI community there is growing interest in moving beyond cognition and expanding into the social, emotional, and bodily aspects of the human-computer experience. Sex lies at the intersection of these concerns, and indeed outside of HCI, has become a central topic for anthropology, behavioral sciences, and other areas of intellectual inquiry. Examining sex and themes related to it has benefited these disciplines and we intend to understand how it can contribute to HCI. There is a tendency to desexualize technology, despite the presence of sex and sexuality in a variety of interactions, including the use of the internet …

Hamiltonicity And Colorings Of Arrangement Graphs, Stefan Felsner, Ferran Hurtado, Marc Noy, Ileana Streinu

Computer Science: Faculty Publications

We study connectivity, Hamilton path and Hamilton cycle decomposition, 4-edge and 3-vertex coloring for geometric graphs arising from pseudoline (affine or projective) and pseudocircle (spherical) arrangements. While arrangements as geometric objects are well studied in discrete and computational geometry, their graph theoretical properties seem to have received little attention so far. In this paper we show that they provide well-structured examples of families of planar and projective-planar graphs with very interesting properties. Most prominently, spherical arrangements admit decompositions into two Hamilton cycles; this is a new addition to the relatively few families of 4-regular graphs that are known to have …

Seasonal Variation In The Stable Isotopic Composition Of Precipitation In The Tropical Montane Forests Of Monteverde, Costa Rica, Amy L. Rhodes, Andrew J. Guswa, Silvia E. Newell

Engineering: Faculty Publications

Climate and land use change may diminish orographic clouds over tropical montane forests, stressing biota and water resources during dry seasons. From 2003 to 2005 we measured the stable isotopic composition of precipitation and throughfall in Monteverde, Costa Rica, to distinguish convective, wet season rainfall associated with the Intertropical Convergence Zone (ITCZ) from dry season, orographic rain produced by northeasterly trade winds. While event-to-event fluctuations of δ18O and δ2H are high, monthly samples reveal a seasonal signal that may be used to trace water through the hydrologic cycle. Deuterium excess indicates that water evaporated from land is an important flux …

A Note On The Engulfing Property And The R 1+Α -Regularity Of Convex Functions In Carnot Groups, Luca Capogna, Diego Maldonado

Mathematics Sciences: Faculty Publications

We study the engulfing property for convex functions in Carnot groups. As an application we show that the horizontal gradient of functions with this property is Hölder continuous.

Interval Timer Control Of Puberty In Photoinhibited Siberian Hamsters, Ho Park Jin, Alexander S. Kauffman, Matthew J. Paul, Matthew P. Butler, Annaliese K. Beery, Ruth M. Costantini, Irving Zucker

Neuroscience: Faculty Publications

Puberty, which is markedly delayed in male Siberian hamsters (Phodopus sungorus) born into short day lengths, is controlled by an interval timer regulated by the duration of nocturnal melatonin secretion. Properties of the interval timer were assessed by perturbing normal patterns of melatonin secretion in males gestated and maintained thereafter in 1 of 2 short day lengths, 10 h light/day (10L) or 12L. Melatonin secretion of short-day hamsters was suppressed by constant light treatment or modified by daily injection of propranolol to mimic nocturnal melatonin durations typical of long-day hamsters. Constant light treatment during weeks 3 to 5 induced early …

Meridians 7:1, Paula J. Giddings

Meridians: Feminism, Race, Transnationalism

One theme that threads through this volume of Merjdjans is how globalization, made possible by advances in science and technology, can also affirm antimodern practices which have particularly affected women of color. Dispersals, disturbances, and porous borders have reified nationalisms that, in liberatory moments, raise political consciousness, but then too often settle with the thud of circumscribing tradition upon the bodies of women. A number of essays reflect the effort to counter the trend through activism and reconceptualize the role of women through the arts, memory, and the questioning of alleged remedial institutional practices and scholarship....

Exponents For B-Stable Ideals, Eric Sommers, Julianna Tymoczko

Mathematics Sciences: Faculty Publications

Let G be a simple algebraic group over the complex numbers containing a Borel subgroup B. Given a B-stable ideal I in the nilradical of the Lie algebra of B, we define natural numbers m 1, m 2,. . .,m k which we call ideal exponents. We then propose two conjectures where these exponents arise, proving these conjectures in types A n, B n, C n and some other types. When I = 0, we recover the usual exponents of G by Kostant (1959), and one of our conjectures reduces to a well-known factorization of the Poincaré polynomial of the …

Preheating With Trilinear Interactions: Tachyonic Resonance, Jean-François Dufaux, Gary Felder, Lev Kofman, Marco Peloso, Dmitry Podolsky

Physics: Faculty Publications

We investigate the effects of bosonic trilinear interactions in preheating after chaotic inflation. A trilinear interaction term allows for the complete decay of the massive inflaton particles, which is necessary for the transition to radiation domination. We found that typically the trilinear term is subdominant during early stages of preheating, but it actually amplifies parametric resonance driven by the four-legs interaction. In cases where the trilinear term does dominate during preheating, the process occurs through periodic tachyonic amplifications with resonance effects, which is so effective that preheating completes within a few inflaton oscillations. We develop an analytic theory of this …

Reviewed Work(S): The Evolution Of English Collecting: The Reception Of Italian Art In The Tudor And Stuart Periods By Edward Chaney, Ed, John E. Moore

Art: Faculty Publications

No abstract provided.

Boundary Fragment Matching And Articulated Pose Under Occlusion, Nicholas Howe

Computer Science: Faculty Publications

Silhouette recognition can reconstruct the three-dimensional pose of a human subject in monocular video so long as the camera’s view remains unoccluded by other objects. This paper develops a shape representation that can describe and compare partial shapes, extending the silhouette recognition technique to apply to video with occlusions. The new method operates without human intervention, and experiments demonstrate that it can reconstruct accurate three-dimensional articulated pose tracks from single-camera walking video despite occlusion of one-third to one-half of the subject.

Reviewed Work(S): The Urban Development Of Rome In The Age Of Alexander Vii By Dorothy Metzger Habel, John E. Moore

Art: Faculty Publications

No abstract provided.

Seasonal Sediment Transport And Unusually Large Spit Development At Sandy Point, San Salvador, Bahamas, Vincent J. Voegeli, Alicia L. Simonti, H. Allen Curran

Geosciences: Faculty Publications

Reprinted from: R.L. Davis & D. Gamble, eds., Proceedings of the 12th Symposium on the Geology of the Bahamas and Other Carbonate Regions, San Salvador, Gerace Research Center

Generativity And Successful Parenting: An Analysis Of Young Adult Outcomes, Bill E. Peterson

Psychology: Faculty Publications

Generativity scores were assessed in parents and correlated with offspring outcomes. The offspring were participants in a longitudinal study spanning their first and senior years of college. Generativity of parents was positively related to offspring agreeableness and conscientiousness. Parental generativity was also related to offspring scores on future time orientation and positive affect. In addition, generative parents seemed to model their political interests to offspring, and that modeling was related to children’s higher scores on generativity and greater interest in politics. Parental generativity was also related to offspring religiosity. Most of these relationships remained significant after controlling for offspring scores …

Beginning Teachers And The Emotional Drama Of The Classroom, Sam M. Intrator

Education and Child Study: Faculty Publications

As a teacher educator, the author believes that he must prepare teachers to go forth into schools with a deep understanding of the subjects they will teach, an appreciation for how students learn, and a repertoire of instructional strategies that will help them make learning come alive for their students. As they develop these skills, they must simultaneously work on resolving four inescapable challenges: First, they have to figure out what it means to be a novice. Second, although teaching is intellectually challenging, it is also chock full of emotional drama. How students negotiate the emotional terrain of teaching is …

Hiring Criteria In Biology Departments Of Academic Institutions, Christine M. Fleet, Meredith F.N. Rosser, Rebecca A. Zufall, Marney C. Pratt, Tracy S. Feldman, Paula P. Lemons

Biological Sciences: Faculty Publications

We surveyed faculty in the biology departments of US institutions of higher education to compare the experience and training valued by faculty at hiring institutions with the experience and training most graduate students receive. Our data show that associate, baccalaureate, and master's institutions value teaching experience and skills more highly than research skills. In contrast, doctoral institutions place a higher value on the ability to publish research and obtain outside funding. These findings provide quantitative and qualitative insight into discrepancies between the values of those who train graduate students in biology and the expectations of the institutions likely to hire …

The Conventional Status Of Reflexive Awareness: What's At Stake In A Tibetan Debate?, Jay L. Garfield

Philosophy: Faculty Publications

No abstract provided.

Meridians 6:2, Paula J. Giddings

Meridians: Feminism, Race, Transnationalism

When the renowned Egyptian physician-psychiatrist, writer, and activist Nawal el Saadawi first told me of her plans to hold a conference entitled "Women, Creativity, and Dissidence" in Cairo, Egypt, in 2005, I immediately envisioned devoting a special issue to the proceedings. At the time, Dr. el Saadawi—whom I had first met some years before as a board member of Meridians-was a visiting Neilson Professor at Smith, and I eagerly anticipated receiving the papers from the conference that would be coedited by both she and Dr. Obioma Nnaemeka...

Desiccation Responses And Survival Of Sinorhizobium Meliloti Usda 1021 In Relation To Growth Phase, Temperature, Chloride And Sulfate Availability, J. A.C. Vriezen, F. J. De Bruijn, K. Nüsslein

Biological Sciences: Faculty Publications

Aims: To identify physical and physiological conditions that affect the survival of Sinorhizobium meliloti USDA 1021 during desiccation. Methods and Results: An assay was developed to study desiccation response of S. meliloti USDA 1021 over a range of environmental conditions. We determined the survival during desiccation in relation to (i) matrices and media, (ii) growth phase, (iii) temperature, and (iv) chloride and sulfate availability. Conclusions: This study indicates that survival of S. meliloti USDA 1021 during desiccation is enhanced: (i) when cells were dried in the stationary phase, (ii) with increasing drying temperature at an optimum of 37°C, and (iii) …

Determinants Of Hearing Loss In Perforations Of The Tympanic Membrane, Ritvik P. Mehta, John J. Rosowski, Susan E. Voss, Ellen O'Neil, Saumil N. Merchant

Engineering: Faculty Publications

Background: Although tympanic membrane perforations are common, there have been few systematic studies of the structural features determining the magnitude of the resulting conductive hearing loss. Our recent experimental and modeling studies predicted that the conductive hearing loss will increase with increasing perforation size, be independent of perforation location (contrary to popular otologic belief), and increase with decreasing size of the middle-ear and mastoid air space (an idea new to otology).

Objective: To test our predictions regarding determinants of conductive hearing loss in tympanic membrane perforations against clinical data gathered from patients.

Study Design: Prospective clinical study. Setting: Tertiary …

Geometric Restrictions On Producible Polygonal Protein Chains, Erik D. Demaine, Stefan Langerman, Joseph O'Rourke

Computer Science: Faculty Publications

Fixed-angle polygonal chains in three dimensions serve as an interesting model of protein backbones. Here we consider such chains produced inside a "machine" modeled crudely as a cone, and examine the constraints this model places on the producible chains. We call this notion producible, and prove as our main result that a chain whose maximum turn angle is α is producible in a cone of half-angle ≥ α if and only if the chain is flattenable, that is, the chain can be reconfigured without self-intersection to lie flat in a plane. This result establishes that two seemingly disparate classes of …

Domain Architecture Of Protein-Disulfide Isomerase Facilitates Its Dual Role As An Oxidase And An Isomerase In Ero1p-Mediated Disulfide Formation, Mohini Kulp, Eva Maria Frickel, Lars Ellgaard, Jonathan S. Weissman

Chemistry: Faculty Publications

Native disulfide bond formation in eukaryotes is dependent on protein-disulfide isomerase (PDI) and its homologs, which contain varying combinations of catalytically active and inactive thioredoxin domains. However, the specific contribution of PDI to the formation of new disulfides versus reduction/rearrangement of non-native disulfides is poorly understood. We analyzed the role of individual PDI domains in disulfide bond formation in a reaction driven by their natural oxidant, Ero1p. We found that Ero1p oxidizes the isolated PDI catalytic thioredoxin domains, A and A′ at the same rate. In contrast, we found that in the context of full-length PDI, there is an asymmetry …

Equation Of State And Beginning Of Thermalization After Preheating, Dmitry Podolsky, Gary Felder, Lev Kofman, Marco Peloso

Physics: Faculty Publications

We study the out-of-equilibrium nonlinear dynamics of fields after post-inflationary preheating. During preheating, the energy in the homogeneous inflaton is exponentially rapidly transfered into highly occupied out-of-equilibrium inhomogeneous modes, which subsequently evolve towards equilibrium. The infrared modes excited during preheating evolve towards a saturated distribution long before thermalization completes. We compute the equation of state during and immediately after preheating. It rapidly evolves towards radiation domination long before the actual thermal equilibrium is established. The exact time of this transition is a non-monotonic function of the coupling between the inflaton and the decay products, and it varies only very weakly …