478 research outputs found
Degree of substitution in Ethylchlorosilanes
When an organo-magnesium halide is reacted with an excess of trichlorosilane, a mixture of products results according to the equations. If phenyl magnesium bromide is used, a mixture of high boiling products results, the highest boiling point of which is approximately 250° at 14mm. pressure. If ethyl magnesium bromide is used, it may be shown that, making certain assumptions and under the conditions of the experiment, if ethyl magnesium bromide is added to the trichlorosilane, monosubstitution is promoted, whereas if the trichlorosilane is added to the ethyl magnesium bromide, polysubstitution is promoted
Awakening Imagination Through Literature
Great literature can inspire reflection and give birth to transforming grace. Words matter; and because they do, literature often reveals the human condition and suggests avenues for growth and change. This article explores the power of literature to cause a spiritual awakening in school leaders. Several works are discussed as the author leads readers into deeply poetic reflections on the possibility of healing and redemption through reading
A night on the town; New York Actor;The Philadelphia
The Marinello One-acts performed two plays each featuring a large city, comprise the Night on the Town experience from the Marinello One acts in February of 2002.https://collected.jcu.edu/plays/1127/thumbnail.jp
Genome-wide association study of breast density among women of African ancestry
Breast density, the amount of fibroglandular versus fatty tissue in the breast, is a strong breast cancer risk factor. Understanding genetic factors associated with breast density may help in clarifying mechanisms by which breast density increases cancer risk. To date, 50 genetic loci have been associated with breast density, however, these studies were performed among predominantly European ancestry populations. We utilized a cohort of women aged 40-85 years who underwent screening mammography and had genetic information available from the Penn Medicine BioBank to conduct a Genome-Wide Association Study (GWAS) of breast density among 1323 women of African ancestry. For each mammogram, the publicly available LIBRA software was used to quantify dense area and area percent density. We identified 34 significant loci associated with dense area and area percent density, with the strongest signals i
Small-world phenomena and the statistics of linear polymer networks
A regular lattice in which the sites can have long range connections at a
distance l with a probabilty , in addition to the short
range nearest neighbour connections, shows small-world behaviour for . In the most appropriate physical example of such a system,
namely the linear polymer network, the exponent is related to the
exponents of the corresponding n-vector model in the limit, and its
value is less than . Still, the polymer networks do not show
small-world behaviour. Here, we show that this is due a (small value)
constraint on the number q of long range connections per monomer in the
network. In the general space, we obtain a phase boundary
separating regions with and without small-world behaviour, and show that the
polymer network falls marginally in the regular lattice region.Comment: Minor corrections in text, Fig. 3 replace
Development and Validation of the Weight Control Strategies Scale
Objective To develop and validate the Weight Control Strategies Scale (WCSS), a self-report instrument to assess use of specific behaviors thought to facilitate weight loss. Design and Methods Factor analysis was conducted on 323 overweight and obese adults (mean age=48.7±10.9 years, mean BMI=35.4±4.9 kg/m2, 74% female) enrolled in three different behavioral weight loss trials who completed the WCSS prior to starting treatment. To evaluate construct validity, additional data on dietary intake, physical activity, treatment session attendance, and weight change were obtained from a subsample of participants before and after participation in a 48-week weight loss program. Results Principal components analysis with varimax rotation revealed a four component solution for the WCSS, representing the following subscales: Dietary Choices, Self-monitoring Strategies, Physical Activity, and Psychological Coping (a’s from 0.79–0.89). Longitudinal analyses showed that WCSS subscale scores increased during treatment (p’s \u3c0.01). In adjusted models, changes in WCSS total and subscale scores were associated with posttreatment weight loss (p’s \u3c0.01). Additionally, changes in WCSS Dietary Choices and Physical Activity subscales were related to posttreatment changes in total daily kilocalorie consumption (p=0.019) and weekly kilocalorie expenditure through physical activity (p\u3c0.001), respectively. Conclusions Findings support the validity and reliability of the WCSS in a weight loss treatment seeking sample
Automatic Network Fingerprinting through Single-Node Motifs
Complex networks have been characterised by their specific connectivity
patterns (network motifs), but their building blocks can also be identified and
described by node-motifs---a combination of local network features. One
technique to identify single node-motifs has been presented by Costa et al. (L.
D. F. Costa, F. A. Rodrigues, C. C. Hilgetag, and M. Kaiser, Europhys. Lett.,
87, 1, 2009). Here, we first suggest improvements to the method including how
its parameters can be determined automatically. Such automatic routines make
high-throughput studies of many networks feasible. Second, the new routines are
validated in different network-series. Third, we provide an example of how the
method can be used to analyse network time-series. In conclusion, we provide a
robust method for systematically discovering and classifying characteristic
nodes of a network. In contrast to classical motif analysis, our approach can
identify individual components (here: nodes) that are specific to a network.
Such special nodes, as hubs before, might be found to play critical roles in
real-world networks.Comment: 16 pages (4 figures) plus supporting information 8 pages (5 figures
Networking - A Statistical Physics Perspective
Efficient networking has a substantial economic and societal impact in a
broad range of areas including transportation systems, wired and wireless
communications and a range of Internet applications. As transportation and
communication networks become increasingly more complex, the ever increasing
demand for congestion control, higher traffic capacity, quality of service,
robustness and reduced energy consumption require new tools and methods to meet
these conflicting requirements. The new methodology should serve for gaining
better understanding of the properties of networking systems at the macroscopic
level, as well as for the development of new principled optimization and
management algorithms at the microscopic level. Methods of statistical physics
seem best placed to provide new approaches as they have been developed
specifically to deal with non-linear large scale systems. This paper aims at
presenting an overview of tools and methods that have been developed within the
statistical physics community and that can be readily applied to address the
emerging problems in networking. These include diffusion processes, methods
from disordered systems and polymer physics, probabilistic inference, which
have direct relevance to network routing, file and frequency distribution, the
exploration of network structures and vulnerability, and various other
practical networking applications.Comment: (Review article) 71 pages, 14 figure
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