Light Z' Bosons at the Tevatron

New gauge bosons with Standard Model-like couplings to leptons are constrained by collider searches to be heavier than approximately ~1 TeV. A Z' boson with suppressed couplings to leptons, however, could be much lighter and possess substantial couplings to Standard Model quarks. In this article, we consider a new leptophobic Z' gauge boson as a simple and well motivated extension of the Standard Model, and discuss several of its possible signatures at the Tevatron. We find that three of the recent anomalies reported from the Tevatron - in particular the top-quark forward-backward asymmetry and excesses in the 3b and W + 2 jets final states - could be explained by a new Z' with a mass of approximately 150 GeV, relatively large couplings to quarks, and suppressed couplings to electrons and muons. Moreover, we find that such a particle could also mediate the interactions of dark matter, leading to potentially interesting implications for direct detection experiments.Comment: 12 pages, 7 figures. v2, v3: updated references. v4: updated to match published version, including minor revisions to figures 1 and

Grouper culture in floating net cages

The manual describes the culture of groupers (Epinephelus) in floating cages, providing a farming option for grouper growers and also a production alternative to the farmed species being done today, such as shrimp, milkfish and tilapia. The following aspects are covered: species identification for commercially cultured groupers; source of stock; net cage specifications; anchor; hides and shelters; nursery net cage operation; production cages; harvesting; post-harvest; profitability analysis of grouper cage culture; and, cost and return of growing grouper in cages

Photocatalytic oxidation of natural organic matter in water

Increased concentrations of natural organic matter (NOM), a complex mixture of organic substances found in most surface waters, have recently emerged as a substantial environmental issue. NOM has a significant variety of molecular and chemical properties, which in combination with its varying concentrations both geographically and seasonally, introduce the opportunity for an array of interactions with the environment. Due to an observable increase in amounts of NOM in water treatment supply sources, an improved effort to remove naturally-occurring organics from drinking water supplies, as well as from municipal wastewater effluents, is required to continue the development of highly efficient and versatile water treatment technologies. Photocatalysis has received increasing interest from around the world, especially during the last decade, as several investigated processes have been regularly reported to be amongst the best performing water treatment technologies to remove NOM from drinking water supplies and mitigate the formation of disinfection by products. Consequently, this overview highlights recent research and developments on the application of photocatalysis to degrade NOM by means of TiO2-based heterogeneous and homogeneous photocatalysts. Analytical techniques to quantify NOM in water and hybrid photocatalytic processes are also reviewed and discussed

Is an Automatic Control Algorithm Necessary for Centrifugal Pumps?

In order to meet physiologic changes in LVAD patients, VAD manufacturers have been developing automatic control algorithms for rotary blood pumps. However, whether an automatic control algorithm is required for normal physiological functioning is unknown. Physiological patterns may be monitored by analyzing daily VAD parameter data (Speed, Power, and Estimated Flow) as acquired by the HeartWare® LVAS Controller. Experiment: Log files from patients supported on the HeartWare® LVAS which contained VAD parameter data (logged at 15minute intervals) were analyzed for daily performance under various physiological conditions while a constant VAD Speed was maintained. A 12-point moving average of Estimated Flow was calculated to eliminate erratic deviation in flow and provide a visual reference of circadian rhythm. Resulting data was analyzed and presented in a weekly viewable time frame. O\u27Driscoll, G., Tamez, D., & Voskoboynikov, N. (2008). Is an automatic control algorithm necessary for centrifugal pumps? Journal of Cardiac Failure, 14(6), S53. doi:10.1016/j.cardfail.2008.06.167 ISSN: 1532-841

Is Google God? How Do Students Look for Information Today?

Librarians aim to foster an information-literate population. At the same time, we have been grappling with rapidly developing technologies and their impact on how we reach our users. In order to truly reach our audience, we first must know our audience. How does today\u27s student decide where to look for information, in what format, and through which form of interaction? How do students evaluate the information they find? Gerri Foudy, Travis Johnson, and Neal Kaske, librarians at the University of Maryland, and Dan Wendling, a graduate student in the University\u27s College of Information Studies Program, set out to learn about students\u27 information-seeking behaviors from the students themselves. Funded by a research grant from the University of Maryland Libraries, a research study was developed, which used 240+ individual interviews and 12 focus group interviews (with 110 participants in total) to begin answering the following research questions: What are contemporary university students\u27 information-seeking behaviors and what role(s), if any, do libraries and/or librarians play in these behaviors? What are contemporary students\u27 mental models of the tasks performed by librarians? Do these behaviors or mental models differ according to level of matriculation, from freshmen through graduate school? The presenters will describe the research project and present the findings, focusing on how they may provide some insight into what technologies, techniques and information resources are being used by students, their information needs and expectations, and how learning about students\u27 information-seeking behaviors can help make us better teachers

Do Users Write More Insecure Code with AI Assistants?

We conduct the first large-scale user study examining how users interact with an AI Code assistant to solve a variety of security related tasks across different programming languages. Overall, we find that participants who had access to an AI assistant based on OpenAI's codex-davinci-002 model wrote significantly less secure code than those without access. Additionally, participants with access to an AI assistant were more likely to believe they wrote secure code than those without access to the AI assistant. Furthermore, we find that participants who trusted the AI less and engaged more with the language and format of their prompts (e.g. re-phrasing, adjusting temperature) provided code with fewer security vulnerabilities. Finally, in order to better inform the design of future AI-based Code assistants, we provide an in-depth analysis of participants' language and interaction behavior, as well as release our user interface as an instrument to conduct similar studies in the future.Comment: 18 pages, 16 figure