721 research outputs found
Statistical analysis of atmospheric polychlorinated biphenyl concentrations at two urban locations
No full textAtmospheric deposition of persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) is an important source of contamination to many U.S. water bodies, including the Delaware River and Lake Michigan. In this thesis, data on concentrations of PCBs in gas and aerosol phases in Chicago, IL and Camden, NJ were analyzed to identify factors that affect atmospheric PCB concentrations in urban areas. In order to investigate factors driving atmospheric PCB concentrations in Camden, NJ, concentrations of gas and particle-phase PCBs, meteorological parameters (temperature, barometric pressure, wind speed, wind direction, relative humidity, and solar radiation) and three criteria pollutants (ozone, carbon monoxide, and nitrogen oxides) measured during 2000-2003 were analyzed by multi-parameter linear regression. The well-known temperature dependence of gas-phase PCBs was evident (average R2 = 0.62; p < 0.05). Gas phase PCB concentrations displayed weak but significant relationships with ozone, wind speed, relative humidity and solar radiation (p < 0.05). When paired with temperature, only wind speed, relative humidity and/or solar radiation produced significant relationships (p < 0.05). Solar radiation and humidity are themselves negatively correlated (p < 0.05), with relative humidity seeming to be the stronger of the two predictor variables. An advanced factor analysis method, Positive Matrix Factorization (PMF), was used to identify the dominant source types of polychlorinated biphenyls (PCBs) in the atmosphere of Chicago, IL. PMF identified 6 factors. When compared to Aroclor compositions, only factor 1 (which comprised 23% of the PCB mass in the data set) was clearly identifiable as Aroclor 1242. Although PCB levels in most environmental compartments are declining gradually, with half lives on the order of 5 to 20 years, atmospheric PCB concentrations in Chicago displayed a marked increase starting around 2005. Results demonstrate this increase was due to factor 4 (which appears to be a mixture of Aroclors 1248/1254, R2 = 0.674), and factor 5, which resembled Aroclor 1254 (R2 = 0.731). Factors 4 and 5 comprised 24% and 16% of the total PCB mass in the data set, respectively. Factors 3 and 6 displayed an exponential decay with half lives of 3.0 and 5.8 years, respectively.M.S.Includes bibliographical referencesby Dawn M. Caci
Student Rectial, M. Dawn Pear, flute; Irina Vorobieva, piano
No full textScriabin spelled Skryabin in proga
Controlling risk for the telecommuting workforce with an emphasis on ergonomics
Get PDFPlan BTen million people or nearly 4.5 % of the United States workforce characterized themselves as telecommuters at the end of 1998. Telecommuting generally involves extensive use of a personal computer workstation. Ergonomic risk factors identified as repetition, awkward postures, force, and the combination of these factors exist in the traditional office workplace. These risk factors are expected to be present in the telecommuters work situation as well. To maintain the health of employees and reduce potential corporate liability due to employee injuries, risk professionals must control ergonomic risk factors faced by the telecommuter. United States corporations have developed a number of different strategies to address ergonomic risks and they are presented in this study. Two specific strategies used are providing in-home workstation evaluations and furniture for the telecommuter. Several large US companies were informally surveyed to determine whether or not they provide these services to their telecommuting workforce. Similarly, the Occupational Safety and Health Administration has been evaluating different methods to control employee injuries associated with ergonomic factors in the office workplace through regulation. These regulatory strategies are also described in this investigation. Document collection and literature review was used as the primary data collection method throughout the study. In addition to the reviews, a set of questions was prepared to provide a framework for informal interviews with several companies. This interview process was used to collect information on the strategies the selected companies employ to control general and ergonomic risks faced by their telecommuting workforces. Data covering general risks associated with telecommuting was presented in paragraph format. Information collected on corporate risk control strategies was provided in a table format. Finally, a time line was created to present OSHA information related to telecommuting
The communicative accomplishment of mutuality during father-son play in early childhood
No full textThis dissertation reports a three-study investigation of mutuality within self-directed play sessions of four African-American father-son dyads at two points in time. These three studies use multiple methods for systematically analyzing face-to-face interaction occurring within a finite space, namely a play area of a daycare center, during a fixed period of time, approximately 15 minutes. This dissertation develops a systematic approach for studying mutuality as it links to well-being as a quality of every day life and individual development. This research offers communication explanations for how relationships in the early stages of life are formed and a way of thinking about well-being across psychological, cognitive, emotional, and social domains from a communication perspective.
Study 1 uses exploratory microanalytic techniques (Mokros, 2003) to identify units of decision making during father-son play. Through its in-depth and systematic examination of decision making, Study 1 provides a vocabulary for talking about decision making from a communication perspective and ultimately provides a conceptual framework and coding system for identifying features of mutuality within father-son interaction. From insights gleaned from this first study, the research in Study 2 reports a comparative study that focuses on understanding individual differences in the amount and quality of mutuality exhibited within and across four father-son dyads at two points in time. This research concludes with Study 3, a comparative study designed to link Interaction States identified in Study 2 with Command Sequences identified by using the Dyadic Parent-Child Interaction Coding System (DPICS) (Eyeberg &amp;amp; Robinson, 1983).
This study contributes to communication theory and research because it examines the moment-to-moment child-rearing practices in families at risk and speaks to how through communicative practices, fathers and sons are able to construct and sustain moments of mutual focus on a task or each other and what this says about not only how relationships in the early stages of life are developed but also about well-being as a quality of everyday life and individual development.Ph.D.Includes bibliographical references (p. 192-195)
Euclid preparation. The Cosmic Dawn Survey (DAWN) of the Euclid Deep and Auxiliary Fields
Get PDFEuclid will provide deep NIR imaging to 26.5 AB magnitude over 59
deg in its deep and auxiliary fields. The Cosmic DAWN survey complements
the deep Euclid data with matched depth multiwavelength imaging and
spectroscopy in the UV--IR to provide consistently processed Euclid selected
photometric catalogs, accurate photometric redshifts, and measurements of
galaxy properties to a redshift of . In this paper, we present an
overview of the survey, including the footprints of the survey fields, the
existing and planned observations, and the primary science goals for the
combined data set.Comment: 16 pages, 10 figures, submitted to A&A; Updated references; Updated
author lis
Author's personal copy Male black-capped chickadees begin dawn chorusing earlier in response to simulated territorial insertions
No full textVariation in the level of competition for mates and territories is likely to influence the behaviour of competitors. The start of the dawn chorus in songbirds is influenced by a variety of internal factors (e.g. circadian rhythms) and external factors (e.g. light levels, social cues). Here we investigate whether the start time of the dawn chorus is influenced by the singing behaviour of conspecific competitors. Using an Acoustic Location System, we recorded the dawn chorus in neighbourhoods of 5e10 blackcapped chickadees, Poecile atricapillus. We used playback to simulate an unfamiliar male performing a dawn song bout within an existing male's territory. Playback began 15 min before the earliest song sung by any male on the preceding day. Focal males began singing a mean AE SE of 4.3 AE 1.6 min earlier on the day of playback (time relative to sunrise), significantly earlier than on the previous day. We also found a significant communication network level response where neighbouring males began singing 2.3 AE 0.8 min earlier in response to playback. Dawn song bouts of males that received playback were longer, but ended at a similar point relative to sunrise. As this effect of a simulated conspecific on chorus start time is on the scale of only a few minutes, other factors probably play a significant role in shaping the timing of dawn chorus onset. Our results show that animals adjust the timing of their sexual communication in response to increased levels of competition.
This (traumatized, kinky, queer) body holds a story
No full textThe chapter, "This (traumatized, kinky, queer) body holds a story" was written by Amber Dawn (Douglas College Faculty). Personal stories of surviving after the trauma of sexual assault. In the era of #MeToo, we’ve become better at talking about sexual assault. But sexual assault isn’t limited to a single, terrible moment of violence: it stays with survivors, following them wherever they go. Through the voices of twelve diverse writers, Whatever Gets You Through offers a powerful look at the narrative of sexual assault not covered by the headlines—the weeks, months, and years of survival and adaptation that people live through in its aftermath. With a foreword by Jessica Valenti, an extensive introduction by editors Stacey May Fowles and Jen Sookfong Lee, and contributions from acclaimed literary voices such as Alicia Elliott, Elisabeth de Mariaffi, Heather O’Neill, and Juliane Okot Bitek, the collection explores some of the many different forms that survival can take. From ice hockey to kink, boxing to tapestry-making, these striking personal essays address experiences as varied as the writers who have lived them. With candor and insight, each writer shares their own unique account of enduring: the everyday emotional pain and trauma, but also the incredible resilience and strength that can emerge in the aftermath of sexual assault. --From publisher description.Published
Controllable needle-free injection : development and verification of a novel device
Get PDFThesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, June 2006.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections."May 2006."Includes bibliographical references (leaves 32-33).Current needle-free injection technology is based on actuation via compressed springs or gas. These devices are not easy to modify for different depths of injections. This thesis describes the design and verification of a handheld needle-free device which is capable of various injection depths via electrical control of a Lorentz-force voice coil actuator. A benchtop proof-of-concept device was created to prove the concept of needle-free injection using a voice coil. After the successful testing of the proof-of-concept device, a handheld prototype was designed, manufactured, and tested. The controllability of injections was tested on excised sheep tissue in-vitro. The handheld device was also tested in-vivo on sheep midside and was shown to give comparable injections to a needle for delivery of the drug collagenase. The controllable needle-free injection principles described in this thesis could be used in human or veterinary applications.by Dawn M. Wendell.S.M
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