Revealing Compressed Stops Using High-Momentum Recoils

Searches for supersymmetric top quarks at the LHC have been making great progress in pushing sensitivity out to higher mass, but are famously plagued by gaps in coverage around lower-mass regions where the decay phase space is closing off. Within the common stop-NLSP / neutralino-LSP simplified model, the line in the mass plane where there is just enough phase space to produce an on-shell top quark remains almost completely unconstrained. Here, we show that is possible to define searches capable of probing a large patch of this difficult region, with S/B ~ 1 and significances often well beyond 5 sigma. The basic strategy is to leverage the large energy gain of LHC Run 2, leading to a sizable population of stop pair events recoiling against a hard jet. The recoil not only re-establishes a MET signature, but also leads to a distinctive anti-correlation between the MET and the recoil jet transverse vectors when the stops decay all-hadronically. Accounting for jet combinatorics, backgrounds, and imperfections in MET measurements, we estimate that Run 2 will already start to close the gap in exclusion sensitivity with the first few 10s of inverse-fb. By 300/fb, exclusion sensitivity may extend from stop masses of 550 GeV on the high side down to below 200 GeV on the low side, approaching the "stealth" point at m(stop) = m(top) and potentially overlapping with limits from top pair cross section and spin correlation measurements.Comment: 17 pages, 6 figure

A Conceptual Framework for Studying the Sources of Variation in Program Effects

Evaluations of public programs in many fields reveal that (1) different types of programs (or different versions of the same program) vary in their effectiveness, (2) a program that is effective for one group of people might not be effective for other groups of people, and (3) a program that is effective in one set of circumstances may not be effective in other circumstances. This paper presents a conceptual framework for research on such variation in program effects and the sources of this variation. The framework is intended to help researchers -- both those who focus mainly on studying program implementation and those who focus mainly on estimating program effects -- see how their respective pieces fit together in a way that helps to identify factors that explain variation in program effects and thereby support more systematic data collection on these factors. The ultimate goal of the framework is to enable researchers to offer better guidance to policymakers and program operators on the conditions and practices that are associated with larger and more positive effects

Understanding the human value for local wildlife and how a connection with nature can contribute to well-being

The most popular way environmental economists have quantified the worth we hold for wildlife has been through calculating a value for conservation or preservation practices. These typically focus upon endangered or charismatic species, and to an existence or non-use value which somebody holds for the creature in question. This thesis recognises that our value for wildlife may be more diverse than this. Indeed, it is highly feasible that people can derive an important yet cognitively disparate benefit from the animals and plants which they experience every day and which reside within close proximity to their homes. Using a combination of inter-disciplinary theories and techniques, this doctorate seeks to explore how mankind receives ‘nature connectivity’ value from local wildlife. This work implies that by undertaking a ‘warden-style’ role when interacting with the flora and fauna which resides upon our doorsteps, humans can satisfy a separate and distinct aspect of their subjective well-being from that which they establish through classic conservation mechanisms. Furthermore, this satisfaction may act as a substitute for other local social activities which are dwindling in modern UK society, including the participation in community or religious groups. The potential impact of these findings are that we may want to rethink the ways we approach the natural world if people are to maximise the participation in and welfare derived from their engagement with it. This includes attending to the behavioural and social infrastructure which can facilitate the opportunities for people to express and enjoy a connection with nature. More generally, the conjectures made here indicate the importance of understanding not only if values exist for environmental entities, but comprehending when these will be dampened or elevated. Until this can be done successfully, environmental economists will forever be fighting a losing battle to retain natural resources at socially optimum thresholds

TIMP3 Regulation of Macrophage Activation and Apoptosis

Acute respiratory distress syndrome (ARDS) is a lung disease involving profound inflammation. Origins of persistent inflammation in select cases of ARDS are poorly understood, and we propose persistent inflammatory macrophages may be one of its mechanisms. Macrophages polarize to either promote inflammation, or suppress inflammation. Tissue inhibitor of metalloproteinases 3 (TIMP3) reduces the pro-inflammatory polarization in macrophages. Additionally, studies have shown TIMP3 promotes apoptosis, and its absence delays recovery from bleomycin-induced lung injury. We hypothesize that TIMP3 promotes apoptosis of murine macrophages through inhibition of metalloproteinase activity and stabilization of FAS on the cell surface. Pro-inflammatory Timp3-/- bone marrow-derived macrophages (BMDMs) have significantly higher metalloproteinase activity, and significantly lower sFASL-induced apoptosis compared to WT BMDMs measured with FLICA and Annexin V. rTIMP3 treatment rescued both metalloproteinase activity and apoptosis. In conclusion, excessive metalloproteinase activity in Timp3-/- BMDMs is associated with sFASL-induced apoptosis potentially due to metalloproteinase dependent death receptor processing

Time Dependent Clustering Analysis of the Second BATSE Gamma-Ray Burst Catalog

A time dependent two-point correlation-function analysis of the BATSE 2B catalog finds no evidence of burst repetition. As part of this analysis, we discuss the effects of sky exposure on the observability of burst repetition and present the equation describing the signature of burst repetition in the data. For a model of all burst repetition from a source occurring in less than five days we derive upper limits on the number of bursts in the catalog from repeaters and model-dependent upper limits on the fraction of burst sources that produce multiple outbursts.Comment: To appear in the Astrophysical Journal Letters, uuencoded compressed PostScript, 11 pages with 4 embedded figure

Change Blindness in Proximity-Aware Mobile Interfaces

Interface designs on both small and large displays can encourage people to alter their physical distance to the display. Mobile devices support this form of interaction naturally, as the user can move the device closer or further away as needed. The current generation of mobile devices can employ computer vision, depth sensing and other inference methods to determine the distance between the user and the display. Once this distance is known, a system can adapt the rendering of display content accordingly and enable proximity-aware mobile interfaces. The dominant method of exploiting proximity-aware interfaces is to remove or superimpose visual information. In this paper, we investigate change blindness in such interfaces. We present the results of two experiments. In our first experiment we show that a proximity-aware mobile interface results in significantly more change blindness errors than a non-moving interface. The absolute difference in error rates was 13.7%. In our second experiment we show that within a proximity-aware mobile interface, gradual changes induce significantly more change blindness errors than instant changes— confirming expected change blindness behavior. Based on our results we discuss the implications of either exploiting change blindness effects or mitigating them when designing mobile proximity-aware interfaces

Farming: From The Ground Up

With half of all current farmers expected to retire within 10 years and entry-level farmers decreasing 30% since 1987, it appears we need to encourage new, entry-level farmers. This case study tracks how a young farmer started his business and the decisions and issues he dealt with along the way. Decisions discussed include whether to rent or lease land, and possible crop-share arrangements, offering custom operations as a way generate revenue and obtain equipment, crop selection and using labor contractors versus in-house labor