Normal Violence: The Case of Fighting on a College Campus

Researchers have proposed a number of theories to explain how violence becomes normalized and thereby increases the incidence of violent acts. This study explores these theories using the case of interpersonal violence on the campus of a large, Mid-Atlantic university. During the 2012-2013 academic school year, undergraduate participant observers witnessed 150 altercations, and gave detailed descriptions of when and where each altercation occurred, who was involved in them, and what consequences resulted. They also described their thoughts and feelings as they witnessed the physical altercation. Some witnesses reported experiencing fear, distress and sorrow, others experienced no adverse cognitions or emotions, while still others felt amused or entertained. Using bivariate and multivariate analyses, we examined several variables that may explain why the witnesses\u27 psychological reactions varied. These included the gender and age of the witnesses, the extent of physical injury to the fighters, as well as several situational variables such as the time and place of the altercation and the social composition of the bystanders. The study showed that psychological reactions to college fighting were explained by individual, trait-based differences between the witnesses, as well as by variation in the specific situations where the altercations occurred. Drawing on dispositional and situational perspectives, a theory of normal violence is proposed

Increasing Transit Ridership: Lessons from the Most Successful Transit Systems in the 1990s, MTI Report-01-22

This study systematically examines recent trends in public transit ridership in the U.S. during the 1990s. Specifically, this analysis focuses on agencies that increased ridership during the latter half of the decade. While transit ridership increased steadily by 13 percent nationwide between 1995 and 1999, not all systems experienced ridership growth equally. While some agencies increased ridership dramatically, some did so only minimally, and still others lost riders. What sets these agencies apart from each other? What explains the uneven growth in ridership

Research into the cause of brackish marsh recession in the Fraser River estuary

At least 160 ha (30%) of the brackish marsh on Sturgeon Bank in the Fraser River estuary have disappeared since 1989. A collaborative effort between the provincial and federal governments and industry aims to determine the cause(s) of the recession to inform future restoration efforts. Three adjacent low-elevation brackish marshes along the delta front have also receded to varying degrees. River training structures and regular dredging of the Fraser River divert sediments and fresh water, and thus alter sediment and salinity patterns along the delta front. Lesser snow geese (Anser c. caerulescens) preferentially grub bulrush, and the Fraser-Skagit population has increased 2-3 fold over the last three decades. Investigation of the marsh recession to date includes (1) describing historical rates and patterns of recession, (2) assessing the present environment (e.g., sediment accretion rates and salinity regimes), and (3) conducting inferential experiments to identify factors that contribute to marsh loss and prevent recovery. No single recession hypothesis we tested singularly explains the recession. The anticipated effects of climate change, especially sea-level rise, pose additional threats to all tidal marshes in the Fraser River estuary

Adventures in Paragraph Writing: The Development and Refinement of Scalable and Effective Writing Exercises for Large-enrollment Engineering Courses

Adventures in paragraph writing: the development and refinement of scalable and effective writing exercises for large enrollment engineering courses. The ability to communicate effectively is a highly desirable attribute for today’s graduating engineers. Additionally, the inclusion of communication components in technical courses has been shown to enhance learning of technical content and can be leveraged to satisfy non-technical learning outcomes. However, the incorporation of such components in undergraduate engineering curricula remains challenging due to resource limitations, credit hour crunches, and other issues. This paper presents the design considerations and preliminary results from our ongoing work to create an effective, transferrable, low-overhead approach to paragraph writing exercises suitable for inclusion in any large engineering course. Key considerations in the development of these exercises include: identification of the motivations and learning outcomes for each exercise; development and tailoring of writing prompts (questions) appropriate for these outcomes; and the development and implementation of an assessment and feedback strategy,including resource-efficient grading rubrics and techniques.Results are reported from the application of the paragraph writing exercise in a large civil engineering undergraduate fluid mechanics course (120 students; approximately 15 assignments). A primary focus of this first application centered on two key components that must be refined in order for the exercise to be effective and transferrable: (1) the selection of writing prompts, and (2) assessment and feedback. Analysis of student paragraphs highlights the importance of the writing prompts in the success of the exercise, indicating that specific word choice, question focus, and supplemental instruction greatly affected the level of writing students submitted. Some writing prompts were selected to address and enhance technical content in the course, while other writing prompts were developed to broaden student awareness of engineering in societal, environmental, and global contexts. In addition to developing productive writing prompts, the assessment and feedback strategies were evaluated using student surveys and feedback. While minimal marking and holistic rubric assessment methods proved effective from a grading resource standpoint, students were frustrated by the lack of feedback associated with these techniques and uncomfortable with the holistic grading rubric. Data from student surveys point to the importance of giving meaningful feedback to students, and providing them with opportunities to revise their written submissions. Student surveys also highlighted an unforeseen obstacle to the exercise: student resistance to writing in technical courses. We provide several suggestions for overcoming student resistance, as well as improved assessment and feedback strategies that better meet student needs while still not over-burdening instructors and teaching assistants

Symmetric M-ary phase discrimination using quantum-optical probe states

We present a theoretical study of minimum error probability discrimination, using quantum- optical probe states, of M optical phase shifts situated symmetrically on the unit circle. We assume ideal lossless conditions and full freedom for implementing quantum measurements and for probe state selection, subject only to a constraint on the average energy, i.e., photon number. In particular, the probe state is allowed to have any number of signal and ancillary modes, and to be pure or mixed. Our results are based on a simple criterion that partitions the set of pure probe states into equivalence classes with the same error probability performance. Under an energy constraint, we find the explicit form of the state that minimizes the error probability. This state is an unentangled but nonclassical single-mode state. The error performance of the optimal state is compared with several standard states in quantum optics. We also show that discrimination with zero error is possible only beyond a threshold energy of (M - 1)/2. For the M = 2 case, we show that the optimum performance is readily demonstrable with current technology. While transmission loss and detector inefficiencies lead to a nonzero erasure probability, the error rate conditional on no erasure is shown to remain the same as the optimal lossless error rate.Comment: 13 pages, 10 figure

Aerosol meteorology of Maritime Continent for the 2012 7SEAS southwest monsoon intensive study - Part 2: Philippine receptor observations of fine-scale aerosol behavior

Abstract. The largest 7 Southeast Asian Studies (7SEAS) operations period within the Maritime Continent (MC) occurred in the August–September 2012 biomass burning season. Data included were observations aboard the M/Y Vasco, dispatched to the Palawan Archipelago and Sulu Sea of the Philippines for September 2012. At these locations, the Vasco observed MC smoke and pollution entering the southwest monsoon (SWM) monsoonal trough. Here we describe the research cruise findings and the finer-scale aerosol meteorology of this convectively active region. This 2012 cruise complemented a 2-week cruise in 2011 and was generally consistent with previous findings in terms of how smoke emission and transport related to monsoonal flows, tropical cyclones (TC), and the covariance between smoke transport events and the atmosphere's thermodynamic structure. Biomass burning plumes were usually mixed with significant amounts of anthropogenic pollution. Also key to aerosol behavior were squall lines and cold pools propagating across the South China Sea (SCS) and scavenging aerosol particles in their path. However, the 2012 cruise showed much higher modulation in aerosol frequency than its 2011 counterpart. Whereas in 2011 large synoptic-scale aerosol events transported high concentrations of smoke into the Philippines over days, in 2012 measured aerosol events exhibited a much shorter-term variation, sometimes only 3–12 h. Strong monsoonal flow reversals were also experienced in 2012. Nucleation events in cleaner and polluted conditions, as well as in urban plumes, were observed. Perhaps most interestingly, several cases of squall lines preceding major aerosol events were observed, as opposed to 2011 observations where these lines largely scavenged aerosol particles from the marine boundary layer. Combined, these observations indicate pockets of high and low particle counts that are not uncommon in the region. These perturbations are difficult to observe by satellite and very difficult to model. Indeed, the Navy Aerosol Analysis and Prediction System (NAAPS) simulations captured longer period aerosol events quite well but largely failed to capture the timing of high-frequency phenomena. Ultimately, the research findings of these cruises demonstrate the real world challenges of satellite-based missions, significant aerosol life cycle questions such as those the future Aerosol/Clouds/Ecosystems (ACE) will investigate, and the importance of small-scale phenomena such as sea breezes, squall lines, and nucleation events embedded within SWM patterns in dominating aerosol life cycle and potential relationships to clouds

Topology of the pore-region of a K+ channel revealed by the NMR-derived structures of scorpion toxins

AbstractThe architecture of the pore-region of a voltage-gated K+ channel, Kv1.3, was probed using four high affinity scorpion toxins as molecular calipers. We established the structural relatedness of these toxins by solving the structures of kaliotoxin and margatoxin and comparing them with the published structure of charybdotoxin; a homology model of noxiustoxin was then developed. Complementary mutagenesis of Kv1.3 and these toxins, combined with electrostatic compliance and thermodynamic mutant cycle analyses, allowed us to identify multiple toxin-challel interactions. Our analyses reveals the existence of a shallow vestibule at the external entrance to the pore. This vestibule is ∼28−32A˚wide at its outer margin, ∼28−34A˚wide at its base, and ∼4−8A˚deep. The pore is 9–14A˚wide at its external entrance and tapers to a width of 4–5A˚at a depth of ∼5−7A˚from the vestibule. This structural information should directly aid in developing topological models of the pores of related ion channels and facilitate therapeutic drug design

Competition for Cooperation: variability, benefits and heritability of relational wealth in hunter-gatherers

Many defining human characteristics including theory of mind, culture and language relate to our sociality, and facilitate the formation and maintenance of cooperative relationships. Therefore, deciphering the context in which our sociality evolved is invaluable in understanding what makes us unique as a species. Much work has emphasised group-level competition, such as warfare, in moulding human cooperation and sociality. However, competition and cooperation also occur within groups; and inter-individual differences in sociality have reported fitness implications in numerous non-human taxa. Here we investigate whether differential access to cooperation (relational wealth) is likely to lead to variation in fitness at the individual level among BaYaka hunter-gatherers. Using economic gift games we find that relational wealth: a) displays individual-level variation; b) provides advantages in buffering food risk, and is positively associated with body mass index (BMI) and female fertility; c) is partially heritable. These results highlight that individual-level processes may have been fundamental in the extension of human cooperation beyond small units of related individuals, and in shaping our sociality. Additionally, the findings offer insight in to trends related to human sociality found from research in other fields such as psychology and epidemiology