Controlling Hazardous Releases While Protecting Passengers in Civil Infrastructure Systems

The threat of accidental or deliberate toxic chemicals released into public spaces is a significant concern to public safety, and the real-time detection and mitigation of such hazardous contaminants has the potential to minimize harm and save lives. Furthermore, the safe evacuation of occupants during such a catastrophe is of utmost importance. This research entails a comprehensive means to address such scenarios, through both the sensing and control of contaminants, and the modeling of and potential communication to occupants as they evacuate. First, a computational fluid dynamics model has been developed that is capable of detecting and mitigating the hazardous contaminant over several time horizons using model predictive control optimization. Next, an evacuation agent-based model has been designed and coupled with the flow control model to simulate agents evacuating while interacting with a dynamic, threatening environment. Finally, a physical prototype (blower wind tunnel) has been constructed with capability of detection (via Ethernet-connected camera) of and mitigation (via compressed-air operated actuators) of a `contaminant' (i.e. smoke) to test the real-time feasibility of the computational fluid dynamics flow control model.PHDEnvironmental EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/135812/1/srimer_1.pd

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Boston University Medicine was published by the Boston University Medical Campus, and presented stories on events and topics of interest to members of the BU Medical Campus community. It followed the discontinued publication Centerscope as Boston University Medicine from 1991-2005, then continued as Campus & Alumni News from 2006-2013 before returning to the title Boston University Medicine from 2014-present

The development of a web- and a print-based decision aid for prostate cancer screening

Background Whether early detection and treatment of prostate cancer (PCa) will reduce disease-related mortality remains uncertain. As a result, tools are needed to facilitate informed decision making. While there have been several decision aids (DAs) developed and tested, very few have included an exercise to help men clarify their values and preferences about PCa screening. Further, only one DA has utilized an interactive web-based format, which allows for an expansion and customization of the material. We describe the development of two DAs, a booklet and an interactive website, each with a values clarification component and designed for use in diverse settings. Methods We conducted two feasibility studies to assess men\u27s (45-70 years) Internet access and their willingness to use a web- vs. a print-based tool. The booklet was adapted from two previous versions evaluated in randomized controlled trials (RCTs) and the website was created to closely match the content of the revised booklet. Usability testing was conducted to obtain feedback regarding draft versions of the materials. The tools were also reviewed by a plain language expert and the interdisciplinary research team. Feedback on the content and presentation led to iterative modifications of the tools. Results The feasibility studies confirmed that the Internet was a viable medium, as the majority of men used a computer, had access to the Internet, and Internet use increased over time. Feedback from the usability testing on the length, presentation, and content of the materials was incorporated into the final versions of the booklet and website. Both the feasibility studies and the usability testing highlighted the need to address men\u27s informed decision making regarding screening. Conclusions Informed decision making for PCa screening is crucial at present and may be important for some time, particularly if a definitive recommendation either for or against screening does not emerge from ongoing prostate cancer screening trials. We have detailed our efforts at developing print- and web-based DAs to assist men in determining how to best meet their PCa screening preferences. Following completion of our ongoing RCT designed to test these materials, our goal will be to develop a dissemination project for the more effective tool

Initial Findings On The Feasibility Of Real-Time Feedback Control Of A Hazardous Contaminant Released Into Channel Flow By Means Of A Laboratory-Scale Physical Prototype

The threat of accidental or deliberate toxic chemicals released into public spaces is a significant concern to public safety. The real-time detection and mitigation of such hazardous contaminants has the potential to minimize harm and save lives. We develop a computational fluid dynamics (CFD) flow control model with the capability of detecting and mitigating such contaminants. Furthermore, we develop a physical prototype to then test the computer model. The physical prototype is in its final stages of construction. Its current state, along with preliminary examples of the flow control model are presented throughout this paper

Initial Findings on the Feasibility of Real-Time Feedback Control of a Hazardous Contaminant Released Into Channel Flow by Means of a Laboratory-Scale Physical Prototype

The threat of accidental or deliberate toxic chemicals released into public spaces is a significant concern to public safety. The real-time detection and mitigation of such hazardous contaminants has the potential to minimize harm and save lives. We develop a computational fluid dynamics (CFD) flow control model with the capability of detecting and mitigating such contaminants. Furthermore, we develop a physical prototype to then test the computer model. The physical prototype is in its final stages of construction. Its current state, along with preliminary examples of the flow control model are presented throughout this paper

Bounds for Minimum Semidefinite Rank from Superpositions and Cutsets

The real (complex) minimum semidefinite rank of a graph is the minimum rank among all real symmetric (complex Hermitian) positive semidefinite matrices that are naturally associated via their zero-nonzero pattern to the given graph. In this paper we give an upper bound on the minimum semidefinite rank of a graph when the graph is modified from the superposition of two graphs by cancelling some number of edges. We also provide a lower bound for the minimum semidefinite rank of a graph determined by a given cutset. When the complement of the cutset is a star forest these lower and upper bounds coincide and we can compute the minimum semidefinite rank in terms of smaller graphs. This result encompasses the previously known case in which the cut set has order two or smaller. Next we provide results for when the cut set has order three. Using these results we provide an example where the positive semidefinite zero forcing number is strictly greater than the maximum positive semidefinite nullity

2-[18F]FDG-PET/CT in Cancer of Unknown Primary Tumor—A Retrospective Register-Based Cohort Study

We investigated the impact of 2-[18F]FDG-PET/CT on detection rate (DR) of the primary tumor and survival in patients with suspected cancer of unknown primary tumor (CUP), comparing it to the conventional diagnostic imaging method, CT. Patients who received a tentative CUP diagnosis at Odense University Hospital from 2014–2017 were included. Patients receiving a 2-[18F]FDG-PET/CT were assigned to the 2-[18F]FDG-PET/CT group and patients receiving a CT only to the CT group. DR was calculated as the proportion of true positive findings of 2-[18F]FDG-PET/CT and CT scans, separately, using biopsy of the primary tumor, autopsy, or clinical decision as reference standard. Survival analyses included Kaplan–Meier estimates and Cox proportional hazards regression adjusted for age, sex, treatment, and propensity score. We included 193 patients. Of these, 159 were in the 2-[18F]FDG-PET/CT group and 34 were in the CT group. DR was 36.5% in the 2-[18F]FDG-PET/CT group and 17.6% in the CT group, respectively (p = 0.012). Median survival was 7.4 (95% CI 0.4–98.7) months in the 2-[18F]FDG-PET/CT group and 3.8 (95% CI 0.2–98.1) in the CT group. Survival analysis showed a crude hazard ratio of 0.63 (p = 0.024) and an adjusted hazard ratio of 0.68 (p = 0.087) for the 2-[18F]FDG-PET/CT group compared with CT. This study found a significantly higher DR of the primary tumor in suspected CUP patients using 2-[18F]FDG-PET/CT compared with patients receiving only CT, with possible immense clinical importance. No significant difference in survival was found, although a possible tendency towards longer survival in the 2-[18F]FDG-PET/CT group was observed