6,021 research outputs found
Microkelvin thermometry with Bose-Einstein condensates of magnons and applications to studies of the AB interface in superfluid He
Coherent precession of trapped Bose-Einstein condensates of magnons is a
sensitive probe for magnetic relaxation processes in superfluid 3He-B down to
the lowest achievable temperatures. We use the dependence of the relaxation
rate on the density of thermal quasiparticles to implement thermometry in 3He-B
at temperatures below 300 K. Unlike popular vibrating wire or quartz
tuning fork based thermometers, magnon condensates allow for contactless
temperature measurement and make possible an independent in situ determination
of the residual zero-temperature relaxation provided by the radiation damping.
We use this magnon-condensate-based thermometry to study the thermal impedance
of the interface between A and B phases of superfluid 3He. The magnon
condensate is also a sensitive probe of the orbital order-parameter texture.
This has allowed us to observe for the first time the non-thermal signature of
the annihilation of two AB interfaces.Comment: 26 pages, 7 figures, manuscript prepared for EU Microkelvin
Collaboration Workshop 2013. Accepted for publication in Journal of Low
Temperature Physic
Needs assessment for increased physical activity in Columbia schoolchildren [abstract]
School children (n=77, average age= 8 years) at three Columbia schools were given accelerometers to be worn for seven days. Activity counts were collected and subsequently converted to metabolic equivalents (METs) in order to determine moderate or vigorous physical activity (MVPA) levels. This data was then analyzed by race (white and nonwhite), socioeconomic status, age, and gender. A significant difference (t=2.099, p<0.05) was found between white and nonwhite children, especially in terms of weekday activity levels. Current intervention studies are being implemented based upon these findings
A mixed methods approach to understanding the relationship between attachment and child outcomes: The connection of related findings, theory and cultural implications as explored through the perspectives and practices of attachment parents
In Chapter 2 of this paper, a quantitative analysis investigated the association between positive couple interaction and child outcomes (externalizing behavior and social competence) as mediated through positive parenting and a secure parent-child attachment. In Chapter 3, a qualitative approach was used to explore the perspectives and parenting behaviors of mothers who identify as attachment parents Additionally, the implications of attachment theory, evolutionary theory, and the societal context in which parenting practices are embedded are explored. A connection between the quantitative and qualitative findings of this study is drawn in Chapter 4 via the discussion section. In addition, consistencies and inconsistencies were explored between the results of both studies as well as between previous research findings and pre-established theory
Autism spectrum disorders and romantic intimacy
Few would deny that romantic intimacy is an important part of the human experience. People with Autism Spectrum Disorders (ASD) may face impairments in communication, social understanding, and emotional responsiveness; however, the importance of romantic intimacy in their lives is no less significant than it is for typically developing people. In response to the dearth of voice in the literature from people with ASD as well a lack of previous research investigating the romantic perceptions and experiences of people with ASD, I set out to explore the lived experiences of individuals and couples with ASD in regard to romantic intimacy. The lived experience of eight participants including one couple, four individuals, and three guardians of participants with ASD were explored through a qualitative methodology using a Hermeneutic phenomenological approach via a critical disability lens. Three main themes emerged through the data analysis including: What Makes it Work?, What is Challenging?, and How is Intimacy Experienced? Themes that emerged indicated that overall aspects of romantic intimacy are similar for people with ASD and typically developing individuals, including the experience of attraction and various expressions of intimacy. Challenges regarding romantic intimacy are likely to be experienced that stem from characteristics of the disorder including sensory/processing issues and social/communication difficulties. Additional challenges may result from circumstances beyond the individual\u27s control such as his or her living situation and societal messages/pressures. Although such challenges may impede on one\u27s ability to be romantically intimate, a number of features have been identified that may transcend such barriers. Such features have been identified through the compatibility of partners, dedication and hard work on the part of both partners, and through helpful external supports. Implications for support services, interventions, and future areas for research are discussed
Reconciling the Past in Octavia Butler\u27s Kindred
This thesis uses the observations of Nancy J. Peterson on historical wounds as a springboard to discuss Octavia Butler’s novel Kindred and its use of both white and black characters to reexamine the origins of the historical wounds and why they are so difficult to deal with even today. Other scholarly works will be used to further investigate the importance of each character in the story and what they mean to the wound itself. Specifically, Dana is analyzed alongside the other main characters: Rufus, Alice, and Kevin. Though Dana’s relationships with these characters, Kindred’s version of the past can be examined in order to determine why the past is so difficult to overcome and what the novel does to come to an understanding or reconciliation with it. This, in turn, allows for the present to be compared to Butler’s representation of the past as a way of reexamining history
Dental Microwear Analysis of Fossil Parapapio and Theropithecus from Makapansgat cave, South Africa
Understanding Adolescent Physical Activity in the Early Nutrition Transitioning Country of Haiti
The nutrition transition is underway in Haiti, giving rise to the dual burden of malnutrition. Physical activity (PA) plays an important role in mitigating the negative health consequences of nutrition transition and the dual burden, but heretofore this data has been unavailable for Haiti. This dissertation undertook an exploratory needs assessment providing baseline PA data for Haitian adolescents. It evaluated two different PA data collection methodologies: a cross-sectional survey adapted from the IPAQ long-form and objectively measured PA via Actigraph GT1M accelerometers. Next, it identified initial covariates of self-reported and objectively-assessed PA behaviors; data was operationalized as meeting the World Health Organization’s recommendation (WHO REC) of ≥60 minutes of moderate or vigorous PA per day for children and adolescents. Finally, the study qualitatively examined the PA values, beliefs, and behaviors of adolescents via focus groups and structured observations. Survey and accelerometry data identified adolescent age, gender, dietary diversity and caregiver occupation as consistently significant covariates of meeting the WHO REC. Focus group and structured observation data further emphasized gender differences in PA. Qualitative methods also revealed overweight to be considered desirable and beneficial, separating it from obesity, which was considered undesirable and associated with poor health. This study is the first of its kind, representing an important step in characterizing the link between the emergence of the dual burden of malnutrition and its risk factors in Haiti, as well as providing rationale for early adoption of policies and programs regarding PA, nutrition, and other types of assistance programming in Haiti
Graphical workstation capability for reliability modeling
In addition to computational capabilities, software tools for estimating the reliability of fault-tolerant digital computer systems must also provide a means of interfacing with the user. Described here is the new graphical interface capability of the hybrid automated reliability predictor (HARP), a software package that implements advanced reliability modeling techniques. The graphics oriented (GO) module provides the user with a graphical language for modeling system failure modes through the selection of various fault-tree gates, including sequence-dependency gates, or by a Markov chain. By using this graphical input language, a fault tree becomes a convenient notation for describing a system. In accounting for any sequence dependencies, HARP converts the fault-tree notation to a complex stochastic process that is reduced to a Markov chain, which it can then solve for system reliability. The graphics capability is available for use on an IBM-compatible PC, a Sun, and a VAX workstation. The GO module is written in the C programming language and uses the graphical kernal system (GKS) standard for graphics implementation. The PC, VAX, and Sun versions of the HARP GO module are currently in beta-testing stages
GADZOOKS! Antineutrino Spectroscopy with Large Water Cerenkov Detectors
We propose modifying large water \v{C}erenkov detectors by the addition of
0.2% gadolinium trichloride, which is highly soluble, newly inexpensive, and
transparent in solution. Since Gd has an enormous cross section for radiative
neutron capture, with MeV, this would make neutrons visible
for the first time in such detectors, allowing antineutrino tagging by the
coincidence detection reaction (similarly for
). Taking Super-Kamiokande as a working example, dramatic
consequences for reactor neutrino measurements, first observation of the
diffuse supernova neutrino background, Galactic supernova detection, and other
topics are discussed.Comment: 4 pages, 1 figure, submitted to Phys. Rev. Lett. Correspondence to
[email protected], [email protected]
- …