Crime in College Park: understanding crime levels, perceptions, and environmental design in an off-campus student-occupied neighborhood

Gemstone Team Crime Prevention and Perception

A meta-analysis of the effectiveness of intelligent tutoring systems on college students' academic learning

© 2013 American Psychological Association.This meta-analysis synthesizes research on the effectiveness of intelligent tutoring systems (ITS) for college students. Thirty-five reports were found containing 39 studies assessing the effectiveness of 22 types of ITS in higher education settings. Most frequently studied were AutoTutor, Assessment and Learning in Knowledge Spaces, eXtended Tutor-Expert System, and Web Interface for Statistics Education. Major findings include (a) Overall, ITS had a moderate positive effect on college students' academic learning (g = .32 to g = .37); (b) ITS were less effective than human tutoring, but they outperformed all other instruction methods and learning activities, including traditional classroom instruction, reading printed text or computerized materials, computer-assisted instruction, laboratory or homework assignments, and no-treatment control; (c) ITS's effectiveness did not significantly differ by different ITS, subject domain, or the manner or degree of their involvement in instruction and learning; and (d) effectiveness in earlier studies appeared to be significantly greater than that in more recent studies. In addition, there is some evidence suggesting the importance of teachers and pedagogy in ITS-assisted learning.

Effects of task instruction on autobiographical memory specificity in young and older adults

Older adults tend to retrieve autobiographical information that is overly general (i.e., not restricted to a single event, termed the overgenerality effect) relative to young adults' specific memories. A vast majority of studies that have reported overgenerality effects explicitly instruct participants to retrieve specific memories, thereby requiring participants to maintain task goals, inhibit inappropriate responses, and control their memory search. Since these processes are impaired in healthy ageing, it is important to determine whether such task instructions influence the magnitude of the overgenerality effect in older adults. In the current study participants retrieved autobiographical memories during presentation of musical clips. Task instructions were manipulated to separate age-related differences in the specificity of underlying memory representations from age-related differences in following task instructions. Whereas young adults modulated memory specificity based on task demands, older adults did not. These findings suggest that reported rates of overgenerality in older adults' memories might include age-related differences in memory representation, as well as differences in task compliance. Such findings provide a better understanding of the underlying cognitive mechanisms involved in age-related changes in autobiographical memory and may also be valuable for future research examining effects of overgeneral memory on general well-being. © 2013 Taylor & Francis.

Effects of task instruction on autobiographical memory specificity in young and older adults.

Older adults tend to retrieve autobiographical information that is overly general (i.e., not restricted to a single event, termed the overgenerality effect) relative to young adults' specific memories. A vast majority of studies that have reported overgenerality effects explicitly instruct participants to retrieve specific memories, thereby requiring participants to maintain task goals, inhibit inappropriate responses, and control their memory search. Since these processes are impaired in healthy ageing, it is important to determine whether such task instructions influence the magnitude of the overgenerality effect in older adults. In the current study participants retrieved autobiographical memories during presentation of musical clips. Task instructions were manipulated to separate age-related differences in the specificity of underlying memory representations from age-related differences in following task instructions. Whereas young adults modulated memory specificity based on task demands, older adults did not. These findings suggest that reported rates of overgenerality in older adults' memories might include age-related differences in memory representation, as well as differences in task compliance. Such findings provide a better understanding of the underlying cognitive mechanisms involved in age-related changes in autobiographical memory and may also be valuable for future research examining effects of overgeneral memory on general well-being.

Improving cold chain technologies through the use of phase change material

Gemstone Team FRESH

Exploring Musical Diversity in the Collaborative Repertoire from 1880 through 1963

It is essential in musical performance not only to convey the unique language of the composers but also to approach each composition from the perspective of its style. During the 20th century, diverse musical idioms co-existed, sometimes mixing or fusing, yet retaining recognizable characteristics and thereby remaining distinctive. This dissertation explores myriad examples from Late Romanticism/Post- Romanticism, Naturalism, Neo-Classicism, Nationalism and Impressionism composed during this unusually rich period. In order to explore a broad range of collaborative repertoire and to deepen my knowledge of the styles and performance practices relating to these pieces, I studied and performed the repertoire with pianist Eunae Baik–Kim, clarinetist Jihoon Chang, and singers Joshua Brown and Young Joo Lee. The first program featured Post-Romantic, Neo-Classic and Impressionist two-piano works composed by Debussy, Rachmaninoff, and Stravinsky. Each of the three composers used their own distinctive harmonies, rhythms, melodic inventions, pedaling and figurations. In all of the works, both piano parts were densely interwoven, having equal importance. Lied and operatic aria was the focus of the second recital. Brahms’ Vier Ernste Gesänge Op. 121, Ravel’s Don Quichotte a Dulcineé and Italian, French and German operatic arias were the examples of Post-Romanticism and Nationalism. The representative composers were Verdi, Massenet, Korngold, Leoncavallo, Ravel and Wagner. Despite the fact that all of the repertoire was written in traditional musical forms, the composers’ unique voices mark each work as belonging to a particular genre. The third recital focused on Post-Romantic and Impressionistic music written for clarinet and piano: the Première Rhapsodie by Debussy, the Sonata by Poulenc and Brahms’ Sonata in F minor Op. 120, No. 1. These works, although profoundly different in style, share elements of simplicity, clarity and elegance as well as technical virtuosity, articulation and profound musical depth. The three recitals which comprise this dissertation project were performed at the University of Maryland Gildenhorn Recital Hall on February 27, 2010, October 25, 2010, and January 31, 2011. The recitals were recorded on compact disc and are archived within the Digital Repository at the University of Maryland (DRUM).

THE PERFORMER’S INFLUENCE ON FRANCO-BELGIAN COMPOSITIONS FROM 1870 TO 1930

The turn of the 20th century marked an ascendancy of the Franco-Belgian school of composers. French composers were inspired by the great German composers of the Romantic era, and they created their own defined national style that emerged toward the end of the 19th century. The Franco-Belgian composers’ special emphasis on tone, timbre and color encouraged a more individual, personally interpretative approach. These devices underscore the importance and influence a performer can have on the outcome of a piece. I researched the relationship between composers and violinists at a time when the Franco-Belgian style developed and flourished. The Franco-Belgian school of violin playing emerged from the Paris and Brussels conservatories as well as the symbiotic relationship between the performers and composers. Three recitals in collaboration with pianist David Ballena, which comprise this dissertation project, were performed at the University of Maryland. Each recital featured music for violin and piano from 1870 through 1930. The repertoire was chosen to reflect a performer’s influence on a composer. I examined specific composer/performer relationships that helped shape the birth of a newly defined “French” style of playing. My research focused on the stylistic interactions composers, such as César Franck, his disciple Guillaume Lekeu had with the leading prominent Belgian violinist Eugène Ysaye and between Maurice Ravel and the Hungarian violinist Jelly d’Aranyi. I also looked into the personal relationship between friends who inspired each other: Gabriel Fauré and Paul Viardot, Edouard Lalo and Pablo de Sarasate, Claude Debussy and Arthur Hartmann, and the young Lili Boulanger and Yvonne Astruc. Furthermore, I looked into the unfulfilled love between Maurice Ravel and Hélène Jourdan-Morhange, as well as the marriage of Olivier Messiaen with Claire Delbos, both relationships resulting in masterpieces for violin that have remained a part of the standard violin repertoire. My research led me to understand what type of violin playing each composer had in mind while composing, all of which led me to understand the importance a performer has in preserving national styles. The recitals were recorded on compact discs and archived within the Digital Repository at the University of Maryland (DRUM).

BOULANGER, SATIE, AND DEBUSSY: THEIR SPHERES OF INFLUENCE ON FRENCH MELODIE AND AMERICAN ART SONG

This dissertation project explored the spheres of influence on art song by Nadia Boulanger, Erik Satie, and Claude Debussy within Boulangeries, Les Six, and Les Apaches. After World War I, American composers flocked to Paris to study with Boulanger. Boulanger gave her students the confidence to explore their native talents instead of mimicking foreign models. Works by Aaron Copland, Virgil Thomson, Theodore Chanler, John Duke, and Richard Hundley were included in the first dissertation recital on January 31, 2010: The Legacy of Nadia Boulanger: Her Influence on American Song Composers. Satie established a new modern French musical style, and was a catalyst for the formation of Les Six. Ned Rorem came to Paris, and had a close association with Les Six. Works by Satie, and three members of Les Six, Francis Poulenc, Arthur Honegger, Darius Milhaud; and Rorem were featured in the second recital on September 1, 2010: Satie, Selected Members of Les Six, and Rorem in Paris. Debussy was one of the most significant French composers in the late nineteenth century, predating Boulanger and Satie. Young composers exploring new directions were inspired by Debussy, forming the group Les Apaches. The final recital, April 7, 2011, featured works by Debussy and two members of Les Apaches, Maurice Ravel and Manuel de Falla: Debussy: A Catalyst for Les Apaches, Ravel and Falla. Falla‘s less well-known repertoire was presented. This dissertation showed the influence of these three major figures and that they embraced innovation in their own time, along with their followers. Recordings of these three performances may be obtained from the Michelle Smith Performing Arts Library in Clarice Smith Performing Arts Center at the University of Maryland, College Park.

THE PIANO MUSIC OF ROBERT SCHUMANN (1810-1856) AND JOHANNES BRAHMS (1833- 1897): A SURVEY OF CONCERTI, VARIATIONS, AND CHARACTER PIECES

Robert Schumann (1810-1856) and Johannes Brahms (1833-1897), in some ways Robert Schumann's artistic descendant, are the most important and representative German piano composers during the Romantic period. Schumann was already a mature and established musician in 1853 when he first met the young Brahms and recognized his talents, an encounter that had a long-lasting affect on the lives and careers of both men. After Schumann’s mental breakdown and death, Brahms maintained his admiration of Schumann’s music and preserved an intimate relationship with Clara Schumann. In spite of the personal and musical closeness of the two men, Schumann’s music is stylistically distinct from that of Brahms. Brahms followed traditions from Baroque and Classical music, and avoided using images and expressive titles in his music. Brahms extraordinarily intermingled earlier musical forms with multicolored tones of German Romanticism. In contrast, Schumann saw himself as a radical composer devoted to personal emotionalism and spontaneity. He favored programmatic titles for his character pieces and extra-musical references in his music. While developing their own musical styles as German Romantic composers, Schumann and Brahms both utilized the piano as a resourceful tool for self-realization and compositional development. To investigate and compare the main characteristics of Schumann and Brahms’s piano music, I looked at three genres. First, in the category of the piano concerto, I chose two major Romantic works, Schumann’s A minor concerto and Brahms’s B-flat major concerto. Second, for the category of piano variations I included two sets by Brahms because the variation framework was such an important vehicle for him to express his musical thoughts. Schumann’s unique motivic approach to variation is displayed vividly in his character-piece cycle Carnaval. Third, the category of the character piece, perhaps the favorite medium of Romantic expression at the piano, is shown by Schumann’s Papillons and Brahms’s sets of pieces Op.118 and Op.119. This performance dissertation consists of three recitals performed in the Gildenhorn Recital Hall at the University of Maryland, College Park. These recitals are documented on compact disc recordings that are housed within the University of Maryland Library System.

WORKS BY FRANCO-BELGIAN COMPOSERS AND THE VIOLINISTS WHO INSPIRED THEM

In the late nineteenth century, French composers such as Camille Saint- Saens, Cesar Franck, and Claude Debussy worked to elevate instrumental music in late-Romantic period France, creating symphonies, concertos, and chamber ensembles, including duo sonatas. These composers and followers like, Ernest Chausson and Guillaume Lekeu were all influenced by a particular violinist to whom they dedicated their compositions. The primary violinist who inspired these composers was Eugene Ysaye (1858-1931), a brilliant performer and composer. His freedom of expression motivated many prominent French composers to dedicate major works to him. For example, Debussy dedicated his string quartet to Ysaye, who established the Ysaye Quartet and premiered Debussy's composition. In 1886, Franck completed his sonata for violin and piano which he also dedicated to Ysaye. Fritz Kreisler (1875-1962), one of the most talented violinists of his era, had a relationship withYsaye that was quite special. They respected, supported, and befriended each other. To Ysaye, Kreisler dedicated his Recitativo and Scherzo. To Kreisler, Ysaye dedicated one ofhis celebrated Sonatas for Solo Violin. Pablo de Sarasate (1844-1908) was a magnificent Spanish violinist of the late nineteenth century, and his music and performances influenced many composers, especially Saint-Saens, who included Spanish gypsy fragments in his works. These motifs may found in his Havanaise, Introduction and Rondo Capriccioso and Violin Concerto No.3 which were dedicated to Sarasate. My goal for this dissertation project has been to find and present, in three recitals, works by French composers and also works by the violinists who inspired them. As a violinist, I have endeavored to understand the influence of the various violinists on these French composers and how that knowledge can inform my approach to performing these works. In my first recital, with pianist Soo Young Jung, I performed works by Saint-Saens, Ysaye and Sarasate. With pianist Sun Ha Yoon, I performed works by Ysaye, Debussy, Kreisler and Franck in my second recital. My third recital, again with pianist Sun Ha Yoon, featured works by Ysaye, Chausson, and Lekeu. All recitals were recorded and performed at the University ofMaryland, College Park.

The Evolution of Rachmaninov's Pianistic Style from 1892 to 1941 as Seen in Selected Original Works and Transcriptions for Piano

Unlike some other major composer-pianists (Franz Liszt and Alexander Scriabin being the most notable examples), Sergei Rachmaninov did not experience any dramatic changes in his compositional style; one can, however, notice certain stylistic differences between piano works composed during different periods of his long creative life. This dissertation argues that a clear evolution of Rachmaninov's pianistic style through his three creative periods can be traced by examining a selection of his compositions, from his first significant cycle for piano, 5 Marceaux de fantaisie, Op. 3 (1892), all the way through to his last piano work, a transcription of P.I.Tchakovsky's Lullaby, Op. 16, No. 1 (1941). Rachmaninov's life as a composer can be divided into three periods. His early period was ended abruptly by the disastrous premiere ofhis First Symphony in 1897, which caused a deep psychological crisis in the life of the young composer. Piano works of this period are often characterized by relatively simple homophonic texture, when Rachmaninov was clearly influenced by some of his Russian predecessors, most notably Tchaikovsky. His second and most productive period, also known as the period of"Russian maturity," started in 1900, when he began working on the Second Suite for two pianos, Op. 17, and the Second Concerto, Op. 18; this phase ended with the Russian Bolshevik revolution of 1917. Works of this time exhibit a mature style of piano writing, with rich, virtuosic - often considered excessive by many critics - texture and ever-increasing use of chromatic harmonies. Rachmaninov's works of the third period are limited in number owing to the composer's preoccupation with a career as pianist. Original works for piano now give way to revisions of earlier compositions and transcriptions: Rachmaninov's piano writing becomes more efficient and economical without losing any of its virtuosic brilliance. This dissertation project examines in detail, over the course of three piano recitals, a variety of works composed during the "Russian maturity" period, from several Preludes from Op. 23 (1903), the first major cycle for solo piano of the period, to 9 Etudes-Tableaux, Op.39 (1917), the last one; the early period is represented by 3 of 5 Marceaux defantaisie, Op. 3 (1892), while the late period is shown through several piano transcriptions and revised versions of the remaining 2 pieces from Op. 3.

Quantification of biological aging in young adults.

Antiaging therapies show promise in model organism research. Translation to humans is needed to address the challenges of an aging global population. Interventions to slow human aging will need to be applied to still-young individuals. However, most human aging research examines older adults, many with chronic disease. As a result, little is known about aging in young humans. We studied aging in 954 young humans, the Dunedin Study birth cohort, tracking multiple biomarkers across three time points spanning their third and fourth decades of life. We developed and validated two methods by which aging can be measured in young adults, one cross-sectional and one longitudinal. Our longitudinal measure allows quantification of the pace of coordinated physiological deterioration across multiple organ systems (e.g., pulmonary, periodontal, cardiovascular, renal, hepatic, and immune function). We applied these methods to assess biological aging in young humans who had not yet developed age-related diseases. Young individuals of the same chronological age varied in their "biological aging" (declining integrity of multiple organ systems). Already, before midlife, individuals who were aging more rapidly were less physically able, showed cognitive decline and brain aging, self-reported worse health, and looked older. Measured biological aging in young adults can be used to identify causes of aging and evaluate rejuvenation therapies.

Making Young Voters: The Impact of Preregistration on Youth Turnout

© 2016 by the Midwest Political Science Association.Recent research has cast doubt on the potential for various electoral reforms to increase voter turnout. In this article, we examine the effectiveness of preregistration laws, which allow young citizens to register before being eligible to vote. We use two empirical approaches to evaluate the impact of preregistration on youth turnout. First, we implement difference-in-difference and lag models to bracket the causal effect of preregistration implementation using the 2000-2012 Current Population Survey. Second, focusing on the state of Florida, we leverage a discontinuity based on date of birth to estimate the effect of increased preregistration exposure on the turnout of young registrants. In both approaches, we find preregistration increases voter turnout, with equal effectiveness for various subgroups in the electorate. More broadly, observed patterns suggest that campaign context and supporting institutions may help to determine when and if electoral reforms are effective.

Global Rates of Free Hydrogen (H2) Production by Serpentinization and other Abiogenic Processes within Young Ocean Crust

The main conclusion of this dissertation is that global H2 production within young ocean crust (<10 Mya) is higher than currently recognized, in part because current estimates of H2 production accompanying the serpentinization of peridotite may be too low (Chapter 2) and in part because a number of abiogenic H2-producing processes have heretofore gone unquantified (Chapter 3). The importance of free H2 to a range of geochemical processes makes the quantitative understanding of H2 production advanced in this dissertation pertinent to an array of open research questions across the geosciences (e.g. the origin and evolution of life and the oxidation of the Earth’s atmosphere and oceans).

The first component of this dissertation (Chapter 2) examines H2 produced within young ocean crust [e.g. near the mid-ocean ridge (MOR)] by serpentinization. In the presence of water, olivine-rich rocks (peridotites) undergo serpentinization (hydration) at temperatures of up to ~500°C but only produce H2 at temperatures up to ~350°C. A simple analytical model is presented that mechanistically ties the process to seafloor spreading and explicitly accounts for the importance of temperature in H2 formation. The model suggests that H2 production increases with the rate of seafloor spreading and the net thickness of serpentinized peridotite (S-P) in a column of lithosphere. The model is applied globally to the MOR using conservative estimates for the net thickness of lithospheric S-P, our least certain model input. Despite the large uncertainties surrounding the amount of serpentinized peridotite within oceanic crust, conservative model parameters suggest a magnitude of H2 production (~1012 moles H2/y) that is larger than the most widely cited previous estimates (~1011 although previous estimates range from 1010-1012 moles H2/y). Certain model relationships are also consistent with what has been established through field studies, for example that the highest H2 fluxes (moles H2/km2 seafloor) are produced near slower-spreading ridges (<20 mm/y). Other modeled relationships are new and represent testable predictions. Principal among these is that about half of the H2 produced globally is produced off-axis beneath faster-spreading seafloor (>20 mm/y), a region where only one measurement of H2 has been made thus far and is ripe for future investigation.

In the second part of this dissertation (Chapter 3), I construct the first budget for free H2 in young ocean crust that quantifies and compares all currently recognized H2 sources and H2 sinks. First global estimates of budget components are proposed in instances where previous estimate(s) could not be located provided that the literature on that specific budget component was not too sparse to do so. Results suggest that the nine known H2 sources, listed in order of quantitative importance, are: Crystallization (6x1012 moles H2/y or 61% of total H2 production), serpentinization (2x1012 moles H2/y or 21%), magmatic degassing (7x1011 moles H2/y or 7%), lava-seawater interaction (5x1011 moles H2/y or 5%), low-temperature alteration of basalt (5x1011 moles H2/y or 5%), high-temperature alteration of basalt (3x1010 moles H2/y or <1%), catalysis (3x108 moles H2/y or <<1%), radiolysis (2x108 moles H2/y or <<1%), and pyrite formation (3x106 moles H2/y or <<1%). Next we consider two well-known H2 sinks, H2 lost to the ocean and H2 occluded within rock minerals, and our analysis suggests that both are of similar size (both are 6x1011 moles H2/y). Budgeting results suggest a large difference between H2 sources (total production = 1x1013 moles H2/y) and H2 sinks (total losses = 1x1011 moles H2/y). Assuming this large difference represents H2 consumed by microbes (total consumption = 9x1011 moles H2/y), we explore rates of primary production by the chemosynthetic, sub-seafloor biosphere. Although the numbers presented require further examination and future modifications, the analysis suggests that the sub-seafloor H2 budget is similar to the sub-seafloor CH4 budget in the sense that globally significant quantities of both of these reduced gases are produced beneath the seafloor but never escape the seafloor due to microbial consumption.

The third and final component of this dissertation (Chapter 4) explores the self-organization of barchan sand dune fields. In nature, barchan dunes typically exist as members of larger dune fields that display striking, enigmatic structures that cannot be readily explained by examining the dynamics at the scale of single dunes, or by appealing to patterns in external forcing. To explore the possibility that observed structures emerge spontaneously as a collective result of many dunes interacting with each other, we built a numerical model that treats barchans as discrete entities that interact with one another according to simplified rules derived from theoretical and numerical work, and from field observations: Dunes exchange sand through the fluxes that leak from the downwind side of each dune and are captured on their upstream sides; when dunes become sufficiently large, small dunes are born on their downwind sides (“calving”); and when dunes collide directly enough, they merge. Results show that these relatively simple interactions provide potential explanations for a range of field-scale phenomena including isolated patches of dunes and heterogeneous arrangements of similarly sized dunes in denser fields. The results also suggest that (1) dune field characteristics depend on the sand flux fed into the upwind boundary, although (2) moving downwind, the system approaches a common attracting state in which the memory of the upwind conditions vanishes. This work supports the hypothesis that calving exerts a first order control on field-scale phenomena; it prevents individual dunes from growing without bound, as single-dune analyses suggest, and allows the formation of roughly realistic, persistent dune field patterns.

INNOVATIONS IN FRENCH CHAMBER MUSIC AND MÉLODIE (1886 – 1962) – A COLLABORATIVE PIANIST’S PERSPECTIVE

French chamber music in the last quarter of the nineteenth century displayed significant advances in musical innovations and technical developments. As the Parisian public began to favor instrumental music and mélodie over opera, vocal and chamber music with piano became one of the main genres to express French composers’ creativity and individuality. The composers Franck, Debussy, Fauré, Duparc, Ravel, Chausson and Poulenc were the major contributors to this unusually creative period in French music. French mélodies of this period blend precision with lyricism, and demand the performer’s elegance and wit. They show careful settings of the French language’s rhythmic subtleties and increased expressiveness in and importance of the piano accompaniment. The chamber works of this period demanded superior pianistic and instrumental virtuosity while displaying wide ranges of sonority, multiple tone colors, and rhythmic fluidity. The three recitals which comprise this dissertation project were performed at the University of Maryland Gildenhorn Recital Hall on 27 October 2006, All Nations Mission Church (Dayton, NJ) on 5 December 2009, and the Leah M. Smith Lecture Hall of the University of Maryland on 11 May 2010. The repertoire included Poulenc’s Sonata for Oboe and Piano (1962) with oboist Yeongsu Kim, French mélodies by Fauré, Chausson, Debussy, Ravel and Duparc with soprano Jung-A Lee and baritone Hyun-Oh Shin, Poulenc’s Sextet for Piano, Flute, Oboe, Clarinet, Bassoon and Horn (1932-1939) with flutist Katrina Smith, clarinetist Jihoon Chang, bassoonist Erich Heckscher, hornist Heidi Littman and oboist Yeongsu Kim, Debussy’s Sonata for Cello and Piano (1915) with cellist Ji-Sook Shin, Poulenc’s Sonata for Violin and Piano (1942-1949) with violinist Ji-Hee Lim, Franck’s Sonata for Violin and Piano (1886) with violinist Na-Young Cho, Ravel’s Piano Trio (1915) with cellist Ji-Sook Shin and violinist Yu-Jeong Lee and Ravel’s Sonata for Violin and Piano (1927) with violinist Yu-Jeong Lee. The recitals were recorded on compact discs and are archived within the Digital Repository at the University of Maryland (DRUM).