Digital Commons Network^™

Fibonacci Or Quasi-Symmetric Phyllotaxis. Part Ii: Botanical Observations, Stéphane Douady, Christophe Golé

Mathematics Sciences: Faculty Publications

Historically, the study of phyllotaxis was greatly helped by the simple description of botanical patterns by only two integer numbers, namely the number of helices (parastichies) in each direction tiling the plant stem. The use of parastichy num- bers reduced the complexity of the study and created a proliferation of generaliza- tions, among others the simple geometric model of lattices. Unfortunately, these simple descriptive method runs into difficulties when dealing with patterns pre- senting transitions or irregularities. Here, we propose several ways of addressing the imperfections of botanical reality. Using ontogenetic analysis, which follows the step-by-step genesis of the pattern, …

Fibonacci Or Quasi-Symmetric Phyllotaxis. Part I: Why?, Christophe Golé, Jacques Dumais, Stéphane Douady

Mathematics Sciences: Faculty Publications

The study of phyllotaxis has focused on seeking explanations for the occurrence of consecutive Fibonacci numbers in the number of helices paving the stems of plants in the two opposite directions. Using the disk-accretion model, first introduced by Schwendener and justified by modern biological studies, we observe two dis- tinct types of solutions: the classical Fibonacci-like ones, and also more irregular configurations exhibiting nearly equal number of helices in a quasi-square pack- ing, the quasi-symmetric ones, which are a generalization of the whorled patterns. Defining new geometric tools allowing to work with irregular patterns and local transitions, we provide simple …

Modeling Negotiations Over Water And Ecosystem Management: Uncertainty And Political Viability, Rachael E. Goodhue, Susan Stratton Sayre, Leo K. Simon

Economics: Faculty Publications

We present a modeling approach for generating robust predictions about how changes in institutional, economic, and political considerations will influence the outcome of political negotiations over complex water-ecosystem policy debates. Evaluating the political viability of proposed policies is challenging for researchers in these complex natural and political environments; there is limited information with which to map policies to outcomes to utilities or to represent the political process adequately. Our analysis evaluates the viability of policy options using a probabilistic political viability criterion that explicitly recognizes the existence of modeling uncertainty. The approach is used to conduct a detailed case study …

Patchiness Of Ciliate Communities Sampled At Varying Spatial Scales Along The New England Shelf, Jean-David Grattepanche, George B. Mcmanus, Laura A. Katz

Biological Sciences: Faculty Publications

Although protists (microbial eukaryotes) provide an important link between bacteria and Metazoa in food webs, we do not yet have a clear understanding of the spatial scales on which protist diversity varies. Here, we use a combination of DNA fingerprinting (denaturant gradient gel electrophoresis or DGGE) and high-throughput sequencing (HTS) to assess the ciliate community in the class Spirotrichea at varying scales of 1–3 km sampled in three locations separated by at least 25 km—offshore, midshelf and inshore—along the New England shelf. Analyses of both abundant community (DGGE) and the total community (HTS) members reveal that: 1) ciliate communities are …

A Survey Of Visual Analytics Tools For Effective Decision-Making, R. Jordan Crouser, Erina Fukuda, Subashini Sridhar

Computer Science: Faculty Publications

Over the past decade, the visualization for cybersecurity (VizSec) research community has adapted many information visualization techniques to support the critical work of cyber analysts. While these efforts have yielded many specialized tools and platforms, the community lacks a unified approach to the design and implementation of these systems. In this work, we provide a retrospective analysis of the past decade of VizSec publications, with an eye toward developing a more cohesive understanding of the emerging patterns of design:

• We identify common thematic groupings among existing work, as well as interesting patterns of design around the utilization of various …

Looking Into The Crystal Ball: Requirements Evolution Over Time, Alicia M. Grubb, Marsha Chechik

Computer Science: Faculty Publications

Goal modeling has long been used in the literature to model and reason about system requirements, constraints within the domain and environment, and stakeholders' goals. Goal model analysis helps stakeholders answer 'what if' questions enabling them to make tradeoff decisions about their project requirements. However, questions concerning the evolution over time of stakeholder requirements or changes in actor intentionality are not explicitly addressed by current approaches. In this paper, we tackle this problem by presenting a method for specifying changes in intentions over time, and a technique that uses simulation for asking a variety of 'what if' questions about such …

Pushback: Critical Data Designers And Pollution Politics, Kim Fortun, Lindsay Poirier, Alli Morgan, Brandon Costelloe-Kuehn, Mike Fortun

Statistical and Data Sciences: Faculty Publications

In this paper, we describe how critical data designers have created projects that ‘push back’ against the eclipse of environmental problems by dominant orders: the pioneering pollution database Scorecard, released by the US NGO Environmental Defense Fund in 1997; the US Environmental Protection Agency’s EnviroAtlas that brings together numerous data sets and provides tools for valuing ecosystem services; and the Houston Clean Air Network’s maps of real-time ozone levels in Houston. Drawing on ethnographic observations and interviews, we analyse how critical data designers turn scientific data and findings into claims and visualisations that are meaningful in contemporary political terms. The …

Which Public? Whose Goods? What We Know (And What We Don't) About Public Goods In Rural China, Sara A. Newland

Government: Faculty Publications

What have we learned from a decade of research on the provision of public goods in the Chinese countryside? This review article surveys the literature in political science, economics and Chinese area studies. It describes the three dominant types of explanations for variation in the quality of public goods: Local elections, social sanctioning and economic policies. It then argues that these findings are plagued by a set of common problems. Scholars mean different things when they use the term public goods, making their findings difficult to compare. Furthermore, the most common measures of public goods ignore the ways in which …

Unemployment In Iraqi Refugees: The Interaction Of Pre And Post-Displacement Trauma, A. Michelle Wright, Abir Dhalimi, Mark A. Lumley, Hikmet Jamil, Nnamdi Pole, Judith E. Arnetz, Bengt B. Arnetz

Psychology: Faculty Publications

Previous refugee research has been unable to link pre-displacement trauma with unemployment in the host country. The current study assessed the role of pre-displacement trauma, post-displacement trauma, and the interaction of both trauma types to prospectively examine unemployment in a random sample of newly-arrived Iraqi refugees. Participants (N = 286) were interviewed three times over the first two years post-arrival. Refugees were assessed for pre-displacement trauma exposure, post-displacement trauma exposure, a history of unemployment in the country of origin and host country, and symptoms of posttraumatic stress disorder (PTSD) and depression. Analyses found that neither pre-displacement nor post-displacement trauma independently …

Meridians 15:1, Karsonya Wise Whitehead

Meridians: Feminism, Race, Transnationalism

With the increasingly high stakes nature of teaching and the ongoing push to teach within the adopted Common Core, there appears to be very little room for teachers to incorporate the voices and experiences of anyone whose life is not already embedded within the curriculum....

The Biodiversity Of Gastrointestinal Nematodes In South African Wildlife, Chalis J. Bird

Theses, Dissertations, and Projects

In this study, I investigated the diversity of parasites found in cheetah and wild ungulates in South Africa in collaboration with the Samara Private Game Reserve in Graaff Reinet, South Africa. Scat samples were collected over a period of two months, from September November, 2014, and DNA was extracted on the preserve for gastrointestinal nematode analysis. Wildlife was tracked using radio telemetry, tracks, and sign, while habitat and host distribution were documented. The aim was to determine the community composition of gastrointestinal nematodes in the wildlife hosts through molecular identification and to examine the role of host habitat preference, geographical …

Tracing Slow Winds From T Tauri Stars Via Low-Velocity Forbidden Line Emission, M. N. Simon, I. Pascucci, Suzan Edwards, W. Feng, U. Gorti, D. Hollenbach, E. Rigliaco, J. T. Keane

Astronomy: Faculty Publications

Using Keck/HIRES spectra (Δ v ∼ 7 km s−1) we analyze forbidden lines of [O I] 6300 Å, [O I] 5577 Å and [S II] 6731 Å from 33 T Tauri stars covering a range of disk evolutionary stages. After removing a high-velocity component (HVC) associated with microjets, we study the properties of the low-velocity component (LVC). The LVC can be attributed to slow disk winds that could be magnetically (magnetohydrodynamic) or thermally (photoevaporative) driven. Both of these winds play an important role in the evolution and dispersal of protoplanetary material. LVC emission is seen in all 30 stars with …

Neurobehavioral Markers Of Resilience To Depression Amongst Adolescent Exposed To Child Abuse, Meg J. Dennison, Margaret A. Sheridan, Daniel S. Busso, Jessica L. Jenness, Matthew Peverill, Maya L. Rosen, Katie A. Mclaughlin

Neuroscience: Faculty Publications

Childhood maltreatment is strongly associated with depression, which is characterized by reduced reactivity to reward. Identifying factors that mitigate risk for depression in maltreated children is important for understanding etiological links between maltreatment and depression as well as improving early intervention and prevention. We examine whether high reward reactivity at behavioral and neurobiological levels is a marker of resilience to depressive symptomology in adolescence following childhood maltreatment. A sample of 59 adolescents (21 with a history of maltreatment; Mean Age = 16.95 years, SD = 1.44) completed an fMRI task involving passive viewing of emotional stimuli. BOLD signal changes to …

Hard-Wall And Non-Uniform Lattice Monte Carlo Approaches To One-Dimensional Fermi Gases In A Harmonic Trap, Casey E. Berger, Joaquín E. Drut, William J. Porter

Physics: Faculty Publications

We present in detail two variants of the lattice Monte Carlo method aimed at tackling systems in external trapping potentials: a uniform-lattice approach with hard-wall boundary conditions, and a non-uniform Gauss–Hermite lattice approach. Using those two methods, we compute the ground-state energy and spatial density profile for systems of N=4–8 harmonically trapped fermions in one dimension. From the favorable comparison of both energies and density profiles (particularly in regions of low density), we conclude that the trapping potential is properly resolved by the hard-wall basis. Our work paves the way to higher dimensions and finite temperature analyses, as calculations with …

Unfolding Genus-2 Orthogonal Polyhedra With Linear Refinement, Mirela Damian, Erik Demaine, Robin Flatland, Joseph O'Rourke

Mathematics Sciences: Faculty Publications

We show that every orthogonal polyhedron of genus g ≤ 2 can be unfolded without overlap while using only a linear number of orthogonal cuts (parallel to the polyhedron edges). This is the first result on unfolding general orthogonal polyhedra beyond genus- 0. Our unfolding algorithm relies on the existence of at most 2 special leaves in what we call the “unfolding tree” (which ties back to the genus), so unfolding polyhedra of genus 3 and beyond requires new techniques.

Learning In Complex Environments: The Effects Of Background Speech On Early Word Learning, Brianna T.M. Mcmillan, Jenny R. Saffran

Psychology: Faculty Publications

Although most studies of language learning take place in quiet laboratory settings, everyday language learning occurs under noisy conditions. The current research investigated the effects of background speech on word learning. Both younger (22- to 24-month-olds; n = 40) and older (28- to 30-month-olds; n = 40) toddlers successfully learned novel label–object pairings when target speech was 10 dB louder than background speech but not when the signal-to-noise ratio (SNR) was 5 dB. Toddlers (28- to 30-month-olds; n = 26) successfully learned novel words with a 5-dB SNR when they initially heard the labels embedded in fluent speech without background …

The “Phunger Games”: Manuscript Review To Assess Graduating Chemistry Majors, David J. Gorin, Elizabeth R. Jamieson, Kate Queeny, Kevin M. Shea, Carrie G. Read Spray

Chemistry: Faculty Publications

Numerous options exist to assess student performance using standardized, multiple-choice exams at the course and department levels. This paper describes the development and implementation of an alternative department-level assessment for graduating chemistry majors. The assessment detailed here evaluates students’ ability to transfer chemical knowledge from their classes to a real life application, namely the review of a scientific paper. Working in groups of three with full access to reference materials, students review a paper intentionally doctored by the faculty to contain a variety of errors. Student groups identify and correct mistakes in a paper with content spanning numerous chemistry subdisciplines. …

Slip Distribution Of The 2014 Mw=8.1 Pisagua, Northern Chile, Earthquake Sequence Estimated From Coseismic Fore-Arc Surface Cracks, John P. Loveless, Chelsea P. Scott, Richard W. Allmendinger, Gabriel González

Geosciences: Faculty Publications

The 2014 Mw = 8.1 Iquique (Pisagua), Chile, earthquake sequence ruptured a segment of the Nazca-South America subduction zone that last hosted a great earthquake in 1877. The sequence opened >3700 surface cracks in the fore arc of decameter-scale length and millimeter-to centimeter-scale aperture. We use the strikes of measured cracks, inferred to be perpendicular to coseismically applied tension, to estimate the slip distribution of the main shock and largest aftershock. The slip estimates are compatible with those based on seismic, geodetic, and tsunami data, indicating that geologic observations can also place quantitative constraints on rupture properties. The earthquake sequence …

Neilson Library Final Charter, Smith College

The New Neilson Library

Final charter for the New Neilson Library project.

An Analysis Of Tax Forecasting Errors In Ireland, Andrew Hannon, Eimear Leahy, Róisín O'Sullivan

Economics: Faculty Publications

This paper examines the tax revenue forecasting performance of the Department of Finance over the period 1997-2014. While the general forecasting framework used reflects standard international practice, forecasting errors are relatively large by international standards. In almost all cases, we find no evidence of bias in the forecasts when considering the major tax heads over various forecast horizons. A decomposition of the forecast errors reveals substantial contributions from sources other than errors in forecasting the macroeconomic environment or in estimating the previous year’s revenue outturn. This suggests that a formal review of specific procedures and assumptions by the Department could …

Interseismic Deformation And Moment Deficit Along The Manila Subduction Zone And The Philippine Fault System, Ya-Ju Hsu, Shui-Beih Yu, John P. Loveless, Teresito Bacolcol, Renato Solidum, Artemio Luis Jr., Alfie Pelicano, Jochen Woessner

Geosciences: Faculty Publications

We examine interseismic coupling of the Manila subduction zone and fault activity in the Luzon area using a block model constrained by GPS data collected from 1998 to 2015. Estimated long-term slip rates along the Manila subduction zone show a gradual southward decrease from 90–100 mm/yr at the northwest tip of Luzon to 65–80 mm/yr at the southern portion of the Manila Trench. We provide two block models (models A and B) to illustrate possible realizations of coupling along the Manila Trench, which may be used to infer future earthquake rupture scenarios. Model A shows a low coupling ratio …

Acceptability Of Treatments And Services For Individuals With Hoarding Behaviors, Carolyn I. Rodriguez, Amanda Levinson, Sapana R. Patel, Kim Rottier, Jordana Zwerling, Susan Essock, Lee Shuer, Randy O. Frost, Helen Blair Simpson

Psychology: Faculty Publications

Objective To explore the acceptability of currently available treatments and services for individuals who self-report hoarding behaviors. Method Between 10/2013 and 8/2014, participants were invited to complete an online survey that provided them descriptions of eleven treatments and services for hoarding behaviors and asked them to evaluate their acceptability using quantitative (0 [not at all acceptable]−10 [completely acceptable]) Likert scale ratings. The a priori definition of acceptability for a given resource was an average Likert scale score of six or greater. Two well-validated self-report measures assessed hoarding symptom severity: the Saving Inventory-Revised and the Clutter Image Rating Scale. Results Two …

Smoothness Of Subriemannian Isometries, Luca Capogna, Enrico Le Donne

Mathematics Sciences: Faculty Publications

We show that the group of isometries (i.e., distance-preserving homeomorphisms) of an equiregular subRiemannian manifold is a finite-dimensional Lie group of smooth transformations. The proof is based on a new PDE argument, in the spirit of harmonic coordinates, establishing that in an arbitrary subRiemannian manifold there exists an open dense subset where all isometries are smooth.

Behavioral And Emotional Consequences Of Thought Listing Versus Cognitive Restructuring During Discarding Decisions In Hoarding Disorder, Randy O. Frost, Clarissa Ong, Gail Steketee, David F. Tolin

Psychology: Faculty Publications

An essential criterion for hoarding disorder (HD) is difficulty discarding or parting with possessions, yet few studies have examined reactions to actual discarding behaviors. The present study examined whether individuals with HD differed from non-hoarding community controls (CC) in discarding behavior and emotional reactions to discarding. A second purpose was to examine the course of experienced distress following discarding. A third purpose was to determine whether HD participants responded differently to a simple thought listing (TL) instruction or to a cognitive restructuring (CR) protocol. Participants were asked to decide whether to keep or discard (a) a personal possession and (b) …

Kahn Chronicle: Fall 2016, Smith College, Kahn Liberal Arts Institute

Kahn Chronicle

Table of Contents:

Faculty, Staff Invited to Apply for 2017-18 Yearlong Projects
Destroy, Then Restore: Transforming our Lands and Waters (2017-18)
War (2017-18)
Apply for Kahn Short-term Projects is Fall
A Brief Introduction to Kahn Institute Staff
2016-17 Long-Term Projects: Student Fellowships Awarded
Fall Lectures Hosted by the Kahn
Outcomes From Kahn Projects
A Brief Record of Works by Recent Kahn Fellows
A Note From the Director: Safe Spaces

Measurements By Controlled Meteorological Balloons In Coastal Areas Of Antarctica, Lars R. Hole, Alexis Pérez Bello, Tjarda J. Roberts, Paul B. Voss, Timo Vihma

Engineering: Faculty Publications

An experiment applying controlled meteorological (CMET) balloons near the coast of Dronning Maud Land, Antarctica, in January 2013 is described. Two balloons were airborne for 60 and 106 hours with trajectory lengths of 885.8 km and 2367.4 km, respectively. The balloons carried out multiple controlled soundings on the atmospheric pressure, temperature and humidity up to 3.3 km. Wind speed and direction were derived from the balloon drift. Observations were compared with radiosonde sounding profiles from the Halley Research Station, and applied in evaluating simulations carried out with the weather research and forecasting (WRF) mesoscale atmospheric model. The most interesting feature …

Profiling The Macrofilaricidal Effects Of Flubendazole On Adult Female Brugia Malayi Using Rnaseq, Maeghan O'Neill, Cristina Ballesteros, Lucienne Tritten, Erica Burkman, Weam I. Zaky, Jianguo Xia, Andrew Moorhead, Steven A. Williams, Timothy G. Geary

Biological Sciences: Faculty Publications

The use of microfilaricidal drugs for the control of onchocerciasis and lymphatic filariasis (LF) necessitates prolonged yearly dosing. Prospects for elimination or eradication of these diseases would be enhanced by the availability of a macrofilaricidal drug. Flubendazole (FLBZ), a benzimidazole anthel- mintic, is an appealing candidate. FLBZ has demonstrated potent macrofilaricidal effects in a number of experimental rodent models and in one human trial. Unfortunately, FLBZ was deemed unsatisfactory for use in mass drug administration campaigns due to its limited oral bioavailability. A new formulation that enables sufficient bioavailability following oral administration could render FLBZ an effective treatment for onchocerciasis …

Development And Validation Of The Frost Multidimensional Perfectionism Scale–Brief, Alexandra M. Burgess, Randy O. Frost, Patricia Marten Dibartolo

Psychology: Faculty Publications

Twenty-five years ago, one of the first empirically validated measures of perfectionism, the Frost et al. Multidimensional Perfectionism Scale (F-MPS) was published. Since that time, psychometric studies of the original F-MPS have provided a plethora of evidence to support the potential development of a shorter yet still psychometrically robust version of the measure. Using confirmatory factor analyses across community and clinical samples, the current study identifies an eight-item F-MPS-Brief with two dimensions (i.e., striving and evaluative concerns) that evidences good internal consistency, measurement equivalence across ethnicities, and concurrent and convergent validity. This new, short version of the F-MPS captures well …

Construct Validity Evidence For The Male Role Norms Inventory-Short Form: A Structural Equation Modeling Approach Using The Bifactor Model, Ronald F. Levant, Rosalie J. Hall, Ingrid K. Weigold, Eric R. Mccurdy

Psychology: Faculty Publications

The construct validity of the Male Role Norms Inventory-Short Form (MRNI-SF) was assessed using a latent variable approach implemented with structural equation modeling (SEM). The MRNI-SF was specified as having a bifactor structure, and validation scales were also specified as latent variables. The latent variable approach had the advantages of separating effects of general and specific factors and controlling for some sources of measurement error. Data (N = 484) were from a diverse sample (38.8% men of color, 22.3% men of diverse sexualities) of community-dwelling and college men who responded to an online survey. The construct validity of the MRNI-SF …

Segmentation-Free Spotting Of Cuneiform Using Part-Structured Models, Bartosz Bogacz, Nicholas Howe, Mara Mara

Computer Science: Faculty Publications

Cuneiform scripts constitute an immense source of information about ancient history, dating back almost four thousand years. Documents were written by imprinting wedgeshaped impressions into wet clay tablets, and current scholarly practice typically transcribes the resulting markings by hand with ink on paper. This work develops algorithmic methods for cuneiform script, combining feature extraction for cuneiform wedges with prior work on segmentation-free word spotting using part-structured models. We adapt the inkball model used for word spotting to treat wedge features as individual parts arranged in a tree structure. The geometric relationship between query and target is measured by the energy …