5,175 research outputs found
uBoost: A boosting method for producing uniform selection efficiencies from multivariate classifiers
The use of multivariate classifiers, especially neural networks and decision
trees, has become commonplace in particle physics. Typically, a series of
classifiers is trained rather than just one to enhance the performance; this is
known as boosting. This paper presents a novel method of boosting that produces
a uniform selection efficiency in a user-defined multivariate space. Such a
technique is ideally suited for amplitude analyses or other situations where
optimizing a single integrated figure of merit is not what is desired
The Actions and Feelings Questionnaire in Autism and Typically Developed Adults
Open access via Springer Compact Agreement We are grateful to Simon Baron-Cohen and Paula Smith of the Cambridge Autism Centre for the use of the ARC database in distributing the questionnaire, to all participants for completing it, to Eilidh Farquar for special efforts in distributing the link and to Gemma Matthews for advice on using AMOS 23. JHGW is supported by the Northwood Trust.Peer reviewedPublisher PD
Model selection for amplitude analysis
Model complexity in amplitude analyses is often a priori under-constrained
since the underlying theory permits a large number of possible amplitudes to
contribute to most physical processes. The use of an overly complex model
results in reduced predictive power and worse resolution on unknown parameters
of interest. Therefore, it is common to reduce the complexity by removing from
consideration some subset of the allowed amplitudes. This paper studies a
method for limiting model complexity from the data sample itself through
regularization during regression in the context of a multivariate (Dalitz-plot)
analysis. The regularization technique applied greatly improves the
performance. An outline of how to obtain the significance of a resonance in a
multivariate amplitude analysis is also provided
Contexts, Connections, and Clovis: Opportunities for Collaboration Between Information Scientists and Archaeologists
Our poster discusses the potential for collaboration between information scientists and archaeologists. In particular, this poster uses a case study of Clovis spear points to illustrate the importance of collaboration between the two disciplines in order to better understand the management of archaeological data. These artifacts are rare and are curated at widespread utilities across North America. We argue that the focus of collaboration between information scientists and archaeologists should be shifted from field methods to understanding data management practices along with digital metadata acquisition and maintenance. Research in this area should also focus on understanding the innovative data creation and curation approaches archaeologists taken given time and resource constraints. In addition, we will also use the preliminary results of a survey of archaeologistsā research data management practices to help support the potential avenues for collaboration. While the Clovis dataset is informative, many other archaeological datasets could benefit from the attention of information scientists
Shenandoah Valley Partnership: Growing and Enhancing the Food and Beverage Manufacturing Industry
This plan analyzes how the Shenandoah Valley Partnership can grow and enhance its food and beverage manufacturing industry. To answer this question, I interviewed and surveyed food and beverage manufacturers to understand their business needs, as well as interviewed service providers to identify their relationships with this industry. The four main results from the plan were:
There is a need for more capital for the businesses.
There is a labor shortage in the industry.
The Shenandoah Valley has an excellent distribution location.
The industry has a poor relationship with the regionās service providers.
The plan outlines recommendations on how institutions and organizations can better collaborate with the food and beverage industry to improve its growth
Action perception is intact in autism spectrum disorder
Date of Acceptance:10/11/2014. Copyright Ā© 2015 the authors 0270-6474/15/351849-09$15.00/0. Copyright of all material published in The Journal of Neuroscience remains with the authors. The authors grant the Society for Neuroscience an exclusive license to publish their work for the first 6 months. After 6 months the work becomes available to the public to copy, distribute, or display under a Creative Commons Attribution 4.0 International (CC BY 4.0) license.Peer reviewedPublisher PD
Biophysical Studies of Cholesterol in Unsaturated Phospholipid Model Membranes
Cellular membranes contain a staggering diversity of lipids. The lipids are heterogeneously distributed to create regions, or domains, whose physical properties differ from the bulk membrane and play an essential role in modulating the function of resident proteins. Many basic questions pertaining to the formation of these lateral assemblies remain. This research employs model membranes of well-defined composition to focus on the potential role of polyunsaturated fatty acids (PUFAs) and their interaction with cholesterol (chol) in restructuring the membrane environment. Omega-3 (n-3) PUFAs are the main bioactive components of fish oil, whose consumption alleviates a variety of health problems by a molecular mechanism that is unclear. We hypothesize that the incorporation of PUFAs into membrane lipids and the effect they have on molecular organization may be, in part, responsible. Chol is a major constituent in the plasma membrane of mammals. It determines the arrangement and collective properties of neighboring lipids, driving the formation of domains via differential affinity for different lipids.
The molecular organization of 1-[2H31]palmitoyl-2-eicosapentaenoylphosphatidylcholine (PEPC-d31) and 1-[2H31]palmitoyl-2-docosahexaenoylphosphatidylcholine (PDPC-d31) in membranes with sphingomyelin (SM) and chol (1:1:1 mol) was compared by solid-state 2H NMR spectroscopy. Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids are the two major n-3 PUFAs found in fish oil, while PEPC-d31 and PDPC-d31 are phospholipids containing the respective PUFAs at the sn-2 position and a perdeuterated palmitic acid at the sn-1 position. Analysis of spectra recorded as a function of temperature indicates that in both cases, formation of PUFA-rich (less ordered) and SM-rich (more ordered) domains occurred. A surprisingly substantial proportion of PUFA was found to infiltrate the more ordered domain. There was almost twice as much DHA (65%) as EPA (30%). The implication is that n-3 PUFAs can incorporate into lipid rafts, which are domains enriched in SM and chol in the plasma membrane, and potentially disrupt the activity of signaling proteins that reside therein. DHA, furthermore, may be the more potent component of fish oil.
PUFA-chol interactions were also examined through affinity measurements. A novel method utilizing electron paramagnetic resonance (EPR) was developed, to monitor the partitioning of a spin-labeled analog of chol, 3Ī²-doxyl-5Ī±-cholestane (chlstn), between large unilamellar vesicles (LUVs) and methyl-Ī²-cyclodextrin (mĪ²CD). The EPR spectra for chlstn in the two environments are distinguishable due to the substantial differences in tumbling rates, allowing the population distribution ratio to be determined by spectral simulation. Advantages of this approach include speed of implementation and avoidance of potential artifacts associated with physical separation of LUV and mĪ²CD. Additionally, in a check of the method, the relative partition coefficients between lipids measured for the spin label analog agree with values obtained for chol by isothermal titration calorimetry (ITC). Results from LUV with different composition confirmed a hierarchy of decreased sterol affinity for phospholipids with increasing acyl chain unsaturation, PDPC possessing half the affinity of the corresponding monounsaturated phospholipid.
Taken together, the results of these studies on model membranes demonstrate the potential for PUFA-driven alteration of the architecture of biomembranes, a mechanism through which human health may be impacted
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