Boosting Stop Searches with a 100 TeV Proton Collider

A proton-proton collider with center of mass energy around 100 TeV is the energy frontier machine that is likely to succeed the LHC. One of the primary physics goals will be the continued exploration of weak scale naturalness. Here we focus on the pair-production of stops that decay to a top and a neutralino. Most of the heavy stop parameter space results in highly boosted tops, populating kinematic regimes inaccessible at the LHC. New strategies for boosted top-tagging are needed and a simple, detector-independent tagger can be constructed by requiring a muon inside a jet. Assuming 20% systematic uncertainties, this future collider can discover (exclude) stops with masses up to 6.5 (8) TeV with 3000 fb^-1 of integrated luminosity. Studying how the exclusion limits scale with luminosity motivates going beyond this benchmark in order to saturate the discovery potential of the machine.Comment: v2: 16 pages, 17 figures, results updated using NLL+NLO cross sections, journal versio

Public Bikesharing in North America During a Period of Rapid Expansion: Understanding Business Models, Industry Trends & User Impacts, MTI Report 12-29

Public bikesharing—the shared use of a bicycle fleet—is an innovative transportation strategy that has recently emerged in major cities around the world, including North America. Information technology (IT)-based bikesharing systems typically position bicycles throughout an urban environment, among a network of docking stations, for immediate access. Trips can be one-way, round-trip, or both, depending on the operator. Bikesharing can serve as a first-and-last mile connector to other modes, as well as for both short and long distance destinations. In 2012, 22 IT-based public bikesharing systems were operating in the United States, with a total of 884,442 users and 7,549 bicycles. Four IT-based programs in Canada had a total of 197,419 users and 6,115 bicycles. Two IT-based programs in Mexico had a total of 71,611 users and 3,680 bicycles. (Membership numbers reflect the total number of short- and long-term users.) This study evaluates public bikesharing in North America, reviewing the change in travel behavior exhibited by members of different programs in the context of their business models and operational environment. This Phase II research builds on data collected during our Phase I research conducted in 2012. During the 2012 research (Phase I), researchers conducted 14 expert interviews with industry experts and public officials in the United States and Canada, as well as 19 interviews with the manager and/or key staff of IT-based bikesharing organizations. For more information on the Phase I research, please see the Shaheen et al., 2012 report Public Bikesharing in North America: Early Operator and User Understanding. For this Phase II study, an additional 23 interviews were conducted with IT-based bikesharing organizations in the United States, Canada, and Mexico in Spring 2013. Notable developments during this period include the ongoing expansion of public bikesharing in North America, including the recent launches of multiple large bikesharing programs in the United States (i.e., Citi Bike in New York City, Divvy in Chicago, and Bay Area Bike Share in the San Francisco Bay Area). In addition to expert interviews, the authors conducted two kinds of surveys with bikesharing users. One was the online member survey. This survey was sent to all people for whom the operator had an email address.The population of this survey was mainly annual members of the bikesharing system, and the members took the survey via a URL link sent to them from the operator. The second survey was an on-street survey. This survey was designed for anyone, including casual users (i.e., those who are not members of the system and use it on a short-term basis), to take “on-street” via a smartphone. The member survey was deployed in five cities: Montreal, Toronto, Salt Lake City, Minneapolis-Saint Paul, and Mexico City. The on-street survey was implemented in three cities: Boston, Salt Lake City, and San Antonio

Large Nc Equivalence and Baryons

In the large Nc limit, gauge theories with different gauge groups and matter content sometimes turn out to be `large Nc equivalent', in the sense of having a set of coincident correlation functions. Large Nc equivalence has mainly been explored in the glueball and meson sectors. However, a recent proposal to dodge the fermion sign problem of QCD with a quark-number chemical potential using large Nc equivalence motivates investigating the applicability of large Nc equivalence to correlation functions involving baryon operators. Here we present evidence that large Nc equivalence extends to the baryon sector, under the same type of symmetry-realization assumptions as in the meson sector, by adapting the classic Witten analysis of large Nc baryons.Comment: 12 pages, 13 figures, v2: minor clarifications to match version published in PRD, v3: typo in fig.5 correcte

The Effects of Test Mode and Contiguity of Material on Geometry Test Scores, Cognitive Load, and Self-Efficacy

In recent years, the development and usage of computer-based tests for educational assessment has grown. The computer-based tests are typically derived from paper-based tests, with the assumption the tests being administered in different modes are equivalent. Studies examining this test mode effect have mainly focused on the test scores, but few have examined other factors important to test performance. The current study examines the test mode effect for geometry test problems, while also putting in perspective the factors of self-efficacy and cognitive load as both are significant components in performance. The results suggest test scores and cognitive load for geometry problems are similar across the test modes, however learners’ self-efficacy significantly decreases when performing the geometry test problems in computer-based test mode. The findings provide insight into the test mode literature and give direction for future lines of research. Keywords: Computer-based testing, Self-efficacy, Test mode effect, Geometry, Cognitive load DOI: 10.7176/JEP/11-12-03 Publication date: April 30th 202

Flexible Invariants Through Semantic Collaboration

Modular reasoning about class invariants is challenging in the presence of dependencies among collaborating objects that need to maintain global consistency. This paper presents semantic collaboration: a novel methodology to specify and reason about class invariants of sequential object-oriented programs, which models dependencies between collaborating objects by semantic means. Combined with a simple ownership mechanism and useful default schemes, semantic collaboration achieves the flexibility necessary to reason about complicated inter-object dependencies but requires limited annotation burden when applied to standard specification patterns. The methodology is implemented in AutoProof, our program verifier for the Eiffel programming language (but it is applicable to any language supporting some form of representation invariants). An evaluation on several challenge problems proposed in the literature demonstrates that it can handle a variety of idiomatic collaboration patterns, and is more widely applicable than the existing invariant methodologies.Comment: 22 page

The effects of temporary exclusion of activity due to wind farm construction on a lobster (Homarus gammarus) fishery suggests a potential management approach

Offshore wind farms form an important part of many countries strategy for responding to the threat of climate change but their development can conflict with other offshore activities. Static gear fisheries targeting sedentary benthic species are particularly affected by spatial management that involves exclusion of fishers. Here we investigate the ecological effect of a short-term closure of a European lobster (Homarus gammarus (L.)) fishing ground, facilitated by the development of the Westermost Rough offshore wind farm located on the north-east coast of the United Kingdom. We also investigate the effects on the population when the site is reopened on completion of the construction. We find that temporary closure offers some respite for adult animals and leads to increases in abundance and size of the target species in that area. Reopening of the site to fishing exploitation saw a decrease in catch rates and size structure, this did not reach levels below that of the surrounding area. Opening the site to exploitation also allows the fishery to recuperate some of the economic loss during the closure. We suggest that our results may indicate that temporary closures of selected areas may be beneficial and offer a management option for lobster fisheries

Evaluation of Dopamine D3 Receptor Antagonists PG01037, PG01042, and VK4-116 Against D1R-induced Dyskinesia

Parkinson’s Disease (PD) results in motor deficits that can be relieved with L-DOPA, a dopamine (DA) replacement therapy. Unfortunately, chronic treatment often leads to L-DOPA-induced dyskinesia (LID), a debilitating side effect characterized by abnormal involuntary movements (AIMs). Overactivity of the direct striatonigral pathway is seen in LID and is characterized by potent changes in D1 and D3 receptors (D1R, D3R). Further, D1R and D3R may physically and functionally interact to form D1R-D3R heteromer thereby potentiating LID. This D1R-D3R heteromer uniquely switches from G-protein dependent to G-protein independent signaling, allowing for an avenue to manage LID. To uncover the role of these pathways in LID, Sprague-Dawley rats were rendered hemi-parkinsonian and treated daily for 2 weeks with L-DOPA (6 mg/kg; s.c.) to induce stable LID. In a within subjects, counterbalanced design, they were then split into treatment groups that received D3R antagonists: PG01037 (10, 30 mg/kg; i.p.), PG01042 (5, 10 mg/kg; i.p.), or VK4-116 (10, 20 mg/kg; i.p.). PG01037 (PG1) is a mixed D3R antagonist, acting at both the G-protein dependent and independent pathways. PG01042 (PG2) acts as an antagonist on G-protein independent signaling and VK4-116 acts as a G-protein dependent antagonist. All drugs were tested against D1R agonist-induced dyskinesia with SKF38393 (2mg/kg; s.c.). The only effects found were with PG2 which implicates promotion of the D1R G-protein dependent pathway as contributing to D1R-induced dyskinesia. Future studies with these drugs and L-DOPA treatment should unveil the importance of D1R, D3R, and D1R-D3R influences in the presence of the natural ligand DA.https://orb.binghamton.edu/research_days_posters_2021/1038/thumbnail.jp