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.

Mental hoop diaries: emotional memories of a college basketball game in rival fans.

The rivalry between the men's basketball teams of Duke University and the University of North Carolina-Chapel Hill (UNC) is one of the most storied traditions in college sports. A subculture of students at each university form social bonds with fellow fans, develop expertise in college basketball rules, team statistics, and individual players, and self-identify as a member of a fan group. The present study capitalized on the high personal investment of these fans and the strong affective tenor of a Duke-UNC basketball game to examine the neural correlates of emotional memory retrieval for a complex sporting event. Male fans watched a competitive, archived game in a social setting. During a subsequent functional magnetic resonance imaging session, participants viewed video clips depicting individual plays of the game that ended with the ball being released toward the basket. For each play, participants recalled whether or not the shot went into the basket. Hemodynamic signal changes time locked to correct memory decisions were analyzed as a function of emotional intensity and valence, according to the fan's perspective. Results showed intensity-modulated retrieval activity in midline cortical structures, sensorimotor cortex, the striatum, and the medial temporal lobe, including the amygdala. Positively valent memories specifically recruited processing in dorsal frontoparietal regions, and additional activity in the insula and medial temporal lobe for positively valent shots recalled with high confidence. This novel paradigm reveals how brain regions implicated in emotion, memory retrieval, visuomotor imagery, and social cognition contribute to the recollection of specific plays in the mind of a sports fan.

AUSTRO-GERMAN VIOLIN REPERTORIE FROM BAROQUE THROUGH ROMANTIC PERIOD

At the end of the sixteenth century, Germany had become one of the most active centers of early Baroque music, and therefore Austro-German music came to dominate Western music. An investigation of violin works written during this period reveals the ways in which Austro-German compositions are extraordinary contributions to the violin repertoire. This research warranted further study and performance of these works in order to determine what influence these composers had on the violin repertoire as a whole. For my dissertation recital project, I trace the history of works for violin focusing the violin concerto repertoire in particular. A genre which remained popular throughout the century, the nineteenth-century concerto served primarily as a vehicle for virtuosic display of the violin and piano as never before. For my research I studied and performed works selected from the Baroque through the Romantic period in three recorded recitals with collaborative pianists Ilya Sinaisky, Sun-ha Yun, and Seyon Lee at the Gildenhorn Recital Hall, Clarice Smith Performing Arts Center. I selected particularly prominent pieces which represent the work of significant composers from each period. The composers discussed include Johann Sebastian Bach (1685-1750), owing to the fact that his works are the culmination of the Baroque era during the first half of the eighteenth century; from the Classical period, Wolfgang Amadeus Mozart (1756-1791) all of whom emerged mixing German and Italian traditions into his own style, and Ludwig van Beethoven (1770-1827), the bridge composer between the Classical and the Romantic periods; Romantic composers, Franz Schubert (1979-1828), Johannes Brahms (1833-1897), Robert Schumann (1810-1856), Felix Mendelssohn (1809-1847), and Max Bruch (1838-1920), all who tended to mix Classic and Romantic elements. As a violinist, I learned that their own original sound, rich harmonies and unique expression made these works worthy of becoming masterpieces. I have relished the opportunity for musical and professional growth in exploring these substantial compositions.

SELECTED AMERICAN VIOLIN WORKS AND THEIR EUROPEAN CONTEXT

For my dissertation, I did a study and performance of American violin works by Charles Ives, Aaron Copland, Leonard Bernstein, and John Corigliano, along with contemporaneous European works by Paul Hindemith, Bela Bartok, Igor Stravinsky, Sergei Prokofiev, and Francis Poulenc. The selected American violin works display the development of a distinctively American style and cover a significant formative period (1914-1963) of American classical music. I intend that the European works form a backdrop for setting in relief any distinctly American qualities possessed by the American works. This is because they cover a similar time period and have significant stylistic affinities and shared influences. My topic stems from a question, "What defines the American Sound?" I attempted to find the answer by looking at the time when American composers consciously searched for their identities, and declared their music to be distinctly American. I found that those distinctive qualities stemmed from three sources: folk music, jazz and hymns. Ives and Copland can be viewed as American in content for their inclusion of such elements, while Bernstein and Corigliano can also be considered as "ideologically American" for their adventurous and eclectic spirit. The simplicity derived from singing a hymn or crooning a popular song; the freedom inspired by jazz; the optimism of accepting all possibilities-these elements inform the common spirit that I found in the music of these four American composers. FIRST RECITAL Sonatafor Violin Solo Op.3112 (1924), Paul Hindemith (1895-1963) Suite Italiennefor Violin and Piano (1932), Igor Stravinsky (1882-1971) Sonatafor Violin and Piano (1963), John Corigliano (b.1938) SECOND RECITAL Second Sonatafor Violin and Piano (1914-17), Charles Ives (1874-1954) First Rhapsody for Violin and Piano (1928), Bela Bart6k (1881-1971) Violin Sonata No.1 infminor (1938-46), Sergei Prokofiev (1891-1953) THIRD RECITAL Nocturne for Violin and Piano (1926), Aaron Copland (1900-1990)Sonata for Violin and Piano, Op. 119 (1942-3, rev.1949), Francis Poulenc (1899-1963)Serenade (after Plato's "Symposium'') (1954) by Leonard Bernstein (1918-1990) The pianists were Sun Ha Yoon (Bart6k) and Grace Eunae Cho (all other repertoire).

MUSICAL EXOTICISM EXPLORED IN PIANO WORKS FROM THE EIGHTEENTH CENTURY THROUGH THE EARLY TWENTIETH CENTURY

Musical exoticism is the evocation of a culture different from that of the composer. It occurs anytime a composer tries to conjure up the music of a country not his own. Although there have been studies of exoticism in the piano works of an individual composer, namely Debussy, there has not been a comprehensive study of musical exoticism in the piano literature as a whole. Upon chronological examination of the piano repertoire, general trends exhibiting exoticism become evident. The first general trend is the emergence of the Turkish style (alia turca) in the eighteenth century. Turkish style soon transmuted to the Hungarian-Gypsy style (all 'ongarese or style hongrois). [In Beethoven's Op. 129, it is alia ingharese.] Composers often alternated between the two styles even in the same composition. By the late nineteenth century, style hongrois was firmly entrenched in the musical language of Austro-German composers, as seen in the works of Brahms. In the nineteenth century, composers turned to the Middle East, North Africa and Spain for inspiration. In particular are several compositions emulating Spanish dance music, culminating in the Spanish works of Debussy and Ravel. The gamelans from Indonesia and objects from the Far East of Japan and China, brought by advances in trade and transportation, captivated the imagination of composers at the turn of the twentieth century. Also in the early twentieth century, composers tried emulating dance and jazz music coming from the Americas, such as the cakewalk, minstrelsy, and the blues. One sees the ever widening sphere of exotic inspiration for western music composers: from the Turkish invasions to the traveling Gypsies of Hungary; to the captivating dance rhythms, soulful cante jondo sections, and guitar flourishes of Spain; expanding further to the far reaches of Asia and the jazzy rhythms of the Americas. This performance dissertation consists of three recitals presented at the University of Maryland, and is documented on compact disc recordings which are housed within the University of Maryland Library System. The recordings present the music of Balakirev, Beethoven, Brahms, Chopin, Debussy, Haydn, Hummel, Milhaud, Moszkowski, Mozart, Ravel, and Schubert.

VARIATION FORMS: A SURVEY THROUGH FOUR CENTURIES OF VIOLIN REPERTOIRE

Variation, or the re-working of existing musical material, has consistently attracted the attention of composers and performers throughout the history of Western music. In three recorded recitals at the University of Maryland School of Music, this dissertation project explores a diverse range of expressive possibilities for violin in seven types of variation form in Austro-German works for violin from the 17th through the 20th centuries. The first program, consisting of Baroque Period works, performed on period instrument, includes the divisions on “John come kiss me now” from The Division Violin by Thomas Baltzar (1631 – 1663), constant bass variations in Sonate Unarum Fidium by Johann Heinrich von Schmelzer (1623 – 1680), arbitrary variation in Sonata for Violin and Continuo in E Major, Op. 1, No. 12 “Roger” by George Friedrich Händel (1685 – 1759), and French Double style, melodic-outline variation in Partita for Unaccompanied Violin in B Minor by Johan Sebastian Bach (1685 – 1750). Theme and Variations, a popular Classical Period format, is represented by the Sonata for Piano and Violin in G Major K. 379 by Wolfgang Amadeus Mozart (1756 – 1791) and Sonata for Violin and Piano in A Major, Op. 47 No. 9 the “Kreutzer” by Ludwig van Beethoven (1770 – 1827). Fantasy for Piano and Violin in C Major D. 934 by Franz Schubert (1797 – 1828) represents the 19th century fantasia variation. In these pieces, the piano and violin parts are densely interwoven, having equal importance. Many 20th century composers incorporated diverse types of variations in their works and are represented in the third recital program comprising: serial variation in the Phantasy for Violin and Piano Op.47 of Arnold Schoenberg (1874 – 1951); a strict form of melodic-outline variation in Sonate für Violine allein, Op. 31, No. 2 of Paul Hindemith (1895 – 1963); ostinato variation in Johan Halvorsen’s (1864 – 1935) Passacaglia for Violin and Viola, after G. F. Handel’s Passacaglia from the Harpsichord Suite No. 7 in G Minor. Pianist Audrey Andrist, harpsichordist Sooyoung Jung, and violist Dong-Wook Kim assisted in these performances.

Effects of Web-Based Self-Reporting: College Students’ Self-Efficacy Regarding Fruit and Vegetable Intake

This study evaluated the effect of an online diet-tracking tool on college students’ self-efficacy regarding fruit and vegetable intake. A convenience sample of students completed online self-efficacy surveys before and after a six-week intervention in which they tracked dietary intake with an online tool. Group one (n=22 fall, n=43 spring) accessed a tracking tool without nutrition tips; group two (n=20 fall, n=33 spring) accessed the tool and weekly nutrition tips. The control group (n=36 fall, n=60 spring) had access to neither. Each semester there were significant changes in self-efficacy from pre- to post-test for men and for women when experimental groups were combined (p<0.05 for all); however, these changes were inconsistent. Qualitative data showed that participants responded well to the simplicity of the tool, the immediacy of feedback, and the customized database containing foods available on campus. Future models should improve user engagement by increasing convenience, potentially by automation.

Improving Photovoltaics with High Luminescence Efficiency Quantum Dot Layers

A solar cell relies on its ability to turn photons into current. Because short wavelength photons are typically absorbed near the top surface of a cell, the generated charge carriers recombine before being collected. But when a layer of quantum dots (nanoscale semiconductor particles) is placed on top of the cell, it absorbs short wavelength photons and emits them into the cell at longer wavelengths, which enables more efficient carrier collection. However, the resulting power conversion efficiency of the system depends critically on the quantum dot luminescence efficiency – the nature of this relationship was previously unknown. Our calculations suggest that a quantum dot layer must have high luminescence efficiency (at least 80%) to improve the current output of existing photovoltaic (PV) cells; otherwise, it may worsen the cell’s efficiency. Our quantum dot layer (using quantum dots with over 85% quantum yield) slightly reduced the efficiency of our PV cells. We observed a decrease in short circuit current of a commercial-grade cell from 0.1977 A to 0.1826 A, a 7.6% drop, suggesting that improved optical coupling from the quantum dot emission into the solar cell is needed. With better optical coupling, we predict current enhancements between ~6% and ~8% for a solar cell that already has an antireflection coating. Such improvements could have important commercial impacts if the coating could be deployed in a scalable fashion.

Deforestation and the spatio-temporal distribution of savannah and forest members of the Simulium damnosum complex in southern Ghana and south-western Togo

Spatio-temporal data on cytotaxonomic identifications of larvae of different members of the Simulium damnosum complex collected from rivers in southern Ghana and south-western Togo from 1975 until 1997 were analysed. When the data were combined, the percentages of savannah blackflies (S. damnosum sensu stricto and S. sirbanum) in the samples were shown to have been progressively increasing since 1975. The increases were statistically significant (P < 0·001), but the rates of increase were not linear. Further analyses were conducted according to the collection seasons and locations of the samples, to account for possible biases such as savannah flies occurring further south in the dry season or a preponderance of later samples from northern rivers having more savannah flies. These analyses showed that the increasing trend was statistically significant (P< 0·0001) only during the periods April to June and October to December. The presence of adult savannah flies carrying infective larvae (L3) indistinguishable from those of Onchocerca volvulus in the study zone was confirmed by examinations of captured flies. The percentages of savannah flies amongst the human-biting populations and the percentages with L3s in the head were higher during dry seasons than wet seasons and the savannah species were found furthest south (5 °25′N) in the dry season. Comparisons of satellite images taken in 1973 and 1990 over a study area in south-western Ghana encompassing stretches of the Tano and Bia rivers demonstrated that there have been substantial increases in urban and savannah areas, at the expense of forest. This was so not only for the whole images but also for subsamples of the images taken at 1, 2, 4, 8 and 16 km distant from sites alongside the River Tano. At every distance from the river, the percentages of pixels classified as urban or savannah have increased in 1990 compared with 1973, while those classified as degraded or dense forest have decreased. The possibility that the proportionate increases in savannah forms of the vectors of onchocerciasis, and hence in the likelihood of the transmission of savannah strains of the disease in formerly forested areas, were related to the decreases in forest cover is discussed.