212,174 research outputs found
Dataset supporting: A sub-nW/kHz Relaxation Oscillator with Ratioed Reference and sub-Clock Power Gated Comparator
No full textMeasured data for results presented in the paper: "A sub-nW/kHz Relaxation Oscillator with Ratioed Reference and sub-Clock Power Gated Comparator" to be published in Journal of Solid State Circuits (JSSC) authored by Anand Savanth, Alex S. Weddell, James Myers, David Flynn and Bashir M. Al-Hashimi</span
Sharing privacy-sensitive access to neuroimaging and genetics data: a review and preliminary validation
No full textThe growth of data sharing initiatives for neuroimaging and genomics represents an exciting opportunity to confront the “small N” problem that plagues contemporary neuroimaging studies while further understanding the role genetic markers play in the function of the brain. When it is possible, open data sharing provides the most benefits. However, some data cannot be shared at all due to privacy concerns and/or risk of re-identification. Sharing other data sets is hampered by the proliferation of complex data use agreements (DUAs) which preclude truly automated data mining. These DUAs arise because of concerns about the privacy and confidentiality for subjects; though many do permit direct access to data, they often require a cumbersome approval process that can take months. An alternative approach is to only share data derivatives such as statistical summaries—the challenges here are to reformulate computational methods to quantify the privacy risks associated with sharing the results of those computations. For example, a derived map of gray matter is often as identifiable as a fingerprint. Thus alternative approaches to accessing data are needed. This paper reviews the relevant literature on differential privacy, a framework for measuring and tracking privacy loss in these settings, and demonstrates the feasibility of using this framework to calculate statistics on data distributed at many sites while still providing privacy.This document is protected by copyright and was first published by Frontiers. All rights reserved. It is reproduced with permission.Peer reviewe
Anand Patwardhan’s Chronicles of Socio-political Realities
No full text Probably India’s best-known documentary film-maker Anand Patwardhan, for close to four decades now, has been raking the country’s political consciousness through his films, which delve into the crux of India’s social and political lives. In this piece, the editors have put together, with Patwardhan’s permission, his writings from his blog ( http://patwardhan.com/wp/ ) on the state atrocities upon Dalits in Maharashtra, the protests through poems and songs by a young group of Dalit activists from Pune—the Kabir Kala Manch (KKM)—and the satyagraha for the freedom of expression by its leaders like Sheetal Sathe; on the Supreme Court judgment that failed the Narmada Bachao Andolan as well as the belief in the justice system, making irrelevant a whole body of evidence built by the Andolan over the years that underlined the huge financial and human costs of the Sardar Sarovar dam project; and on the whole climate of intolerance that was behind the attack on M. F. Husain for his depiction of Hindu goddess Saraswati. This piece also includes a commentary by Alex Napier on Patwardhan’s documentary of the Narmada Bachao Andolan, drawn from Patwardhan’s blog. These are important social commentaries of our times. </jats:p
Decentralized temporal independent component analysis: leveraging fMRI data in collaborative settings
No full textPeer reviewe
A thermo-mechanically-coupled large-deformation theory for amorphous polymers in a temperature range which spans their glass transition
No full textAmorphous thermoplastic polymers are important engineering materials; however, their non-linear, strongly temperature- and rate-dependent elastic-viscoplastic behavior is still not very well understood, and is modeled by existing constitutive theories with varying degrees of success. There is no generally agreed upon theory to model the large-deformation, thermo-mechanically-coupled, elastic-viscoplastic response of these materials in a temperature range which spans their glass transition temperature. Such a theory is crucial for the development of a numerical capability for the simulation and design of important polymer processing operations, and also for predicting the relationship between processing methods and the subsequent mechanical properties of polymeric products. In this paper we extend our recently published theory [Anand, L., Ames, N. M., Srivastava, V., Chester, S. A., 2009. A thermo-mechanically-coupled theory for large deformations of amorphous polymers. Part I: formulation. International Journal Plasticity 25, 1474–1494; Ames, N. M., Srivastava, V., Chester, S. A., Anand, L., 2009. A thermo-mechanically coupled theory for large deformations of amorphous polymers. Part II: applications. International Journal of Plasticity 25, 1495–1539] to fill this need.
We have conducted large strain compression experiments on three representative amorphous polymeric materials – a cyclo-olefin polymer (Zeonex-690R), polycarbonate (PC), and poly(methyl methacrylate) (PMMA) – in a temperature range from room temperature to approximately 50 °C above the glass transition temperature, ϑg [theta subscript g], of each material, in a strain-rate range of ≈10-4 [10 superscript -4]to 10-1 s-1 [10 superscript -1 s superscript -1], and compressive true strains exceeding 100%. We have specialized our constitutive theory to capture the major features of the thermo-mechanical response of the three materials studied experimentally.
We have numerically implemented our thermo-mechanically-coupled constitutive theory by writing a user material subroutine for a widely used finite element program. In order to validate the predictive capabilities of our theory and its numerical implementation, we have performed the following validation experiments: (i) a plane-strain forging of PC at a temperature below ϑg [theta subscript g], and another at a temperature above ϑg [theta subscript g]; (ii) blow-forming of thin-walled semi-spherical shapes of PC above ϑg [theta subscript g]; and (iii) microscale hot-embossing of channels in Zeonex and PMMA above ϑg [theta subscript g]. By comparing the results from this suite of validation experiments of some key features, such as the experimentally-measured deformed shapes and the load-displacement curves, against corresponding results from numerical simulations, we show that our theory is capable of reasonably accurately reproducing the experimental results obtained in the validation experiments.National Science Foundation (U. S.) (Grant no. DMI-0517966)Singapore MIT Alliance Programme in Manufacturing Systems and Technolog
Interview with Anand Kumar
No full text<< Prof. Anand Kumar is a retired professor of sociology at Jawaharlal Nehru University. He was a student at JNU in the 1970s and was a part of a student collective called Free Thinkers at JNU. He shares his experiences of being part of the JP Movement during the Emergency of 1975-77. This material is exhibited as part of the Memories of Change exhibition
COINSTAC: A Privacy Enabled Model and Prototype for Leveraging and Processing Decentralized Brain Imaging Data
No full textThe field of neuroimaging has embraced the need for sharing and collaboration. Data sharing mandates from public funding agencies and major journal publishers have spurred the development of data repositories and neuroinformatics consortia. However, efficient and effective data sharing still faces several hurdles. For example, open data sharing is on the rise but is not suitable for sensitive data that are not easily shared, such as genetics. Current approaches can be cumbersome (such as negotiating multiple data sharing agreements). There are also significant data transfer, organization and computational challenges. Centralized repositories only partially address the issues. We propose a dynamic, decentralized platform for large scale analyses called the Collaborative Informatics and Neuroimaging Suite Toolkit for Anonymous Computation (COINSTAC). The COINSTAC solution can include data missing from central repositories, allows pooling of both open and “closed” repositories by developing privacy-preserving versions of widely-used algorithms, and incorporates the tools within an easy-to-use platform enabling distributed computation. We present an initial prototype system which we demonstrate on two multi-site data sets, without aggregating the data. In addition, by iterating across sites, the COINSTAC model enables meta-analytic solutions to converge to “pooled-data” solutions (i.e., as if the entire data were in hand). More advanced approaches such as feature generation, matrix factorization models, and preprocessing can be incorporated into such a model. In sum, COINSTAC enables access to the many currently unavailable data sets, a user friendly privacy enabled interface for decentralized analysis, and a powerful solution that complements existing data sharing solutions.Peer reviewe
Modeling the growth and dissolution of clots in flowing blood
No full textMultiple interacting mechanisms control the formation and dissolution of clots to
maintain blood in a state of delicate balance. In addition to a myriad of biochemical
reactions, rheological factors also play a crucial role in modulating the response of
blood to external stimuli. The broad stimuli for clot formation were laid out, more
than a century ago, in, what is now referred to as, Virchow��������s triad. To date, a
comprehensive model for clot formation and dissolution, that takes into account the
biochemical, medical and rheological factors, has not been put into place, the existing
models emphasizing either one or the other of the factors. In this dissertation, a model
is developed for clot formation and dissolution that incorporates many of the relevant
crucial factors that have a bearing on the problem. The model, though just a first step
towards understanding a complex phenomenon goes further than previous models in
integrating the biochemical, medical and rheological factors that come into play. The
model is tested in some simple flow situations as part of an attempt to elucidate
Virchow��������s triad. Extensions to the model, along with detailed numerical studies, will
hopefully aid in a clearer understanding of the phenomenon, and in making relevant
clinical correlations
Spatial scaling of structural complexity in plant communities
No full textIn the last decade, it has become well appreciated that disorder-based diversity as a single scalar quantity fails toadequately capture structural complexity in biological communities. Complexity here implies spatial correlation (cooccurrence)between species such that the larger and more intricate the correlations, the more structured thecommunity. Ideally, we should like to measure complexity in terms suitable to compare, say, a rainforest tograssland. But for this, the rules of quantification must be very general. Also, since complexity should summarizethe amount of spatial correlation, any complexity measure is by its very nature scale dependent. Taking these intoconsideration we suggest that Juhász-Nagy information-theoretical coenostate variables offer an adequate basis forthe measurement of the structural complexity within plant communities. We examine the notion of complexity inits broad sense and present a worked example using data from an early stage primary succession on an open-cast coalmine in northern Hungary
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