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Full-Text Articles in Engineering

A Study Of Alterations In Dna Epigenetic Modifications (5mc And 5hmc) And Gene Expression Influenced By Simulated Microgravity In Human Lymphoblastoid Cells, Basudev Chowdhury, Arun Seetharam, Zhiping Wang, Yunlong Liu, Amy C. Lossie, Jyothi Thimmapuram Jan 2016

A Study Of Alterations In Dna Epigenetic Modifications (5mc And 5hmc) And Gene Expression Influenced By Simulated Microgravity In Human Lymphoblastoid Cells, Basudev Chowdhury, Arun Seetharam, Zhiping Wang, Yunlong Liu, Amy C. Lossie, Jyothi Thimmapuram

Cyber Center Publications

Cells alter their gene expression in response to exposure to various environmental changes. Epigenetic mechanisms such as DNA methylation are believed to regulate the alterations in gene expression patterns. In vitro and in vivo studies have documented changes in cellular proliferation, cytoskeletal remodeling, signal transduction, bone mineralization and immune deficiency under the influence of microgravity conditions experienced in space. However microgravity induced changes in the epigenome have not been well characterized. In this study we have used Next-generation Sequencing (NGS) to profile ground-based “simulated” microgravity induced changes on DNA methylation (5-methylcytosine or 5mC), hydroxymethylation (5-hydroxymethylcytosine or 5hmC), and simultaneous gene …


Genome-Wide Profiling Of Histone Modifications (H3k9me2 And H4k12ac) And Gene Expression In Rust (Uromyces Appendiculatus) Inoculated Common Bean (Phaseolus Vulgaris L), Vasudevan Ayyappan, Venu Kalavacharla, Jyothi Thimmapuram, Ketaki P. Bhide, Venkateswara R. Sripathi Jan 2015

Genome-Wide Profiling Of Histone Modifications (H3k9me2 And H4k12ac) And Gene Expression In Rust (Uromyces Appendiculatus) Inoculated Common Bean (Phaseolus Vulgaris L), Vasudevan Ayyappan, Venu Kalavacharla, Jyothi Thimmapuram, Ketaki P. Bhide, Venkateswara R. Sripathi

Cyber Center Publications

Histone modifications such as methylation and acetylation play a significant role in controlling gene expression in unstressed and stressed plants. Genome-wide analysis of such stress-responsive modifications and genes in non-model crops is limited. We report the genome-wide profiling of histone methylation (H3K9me2) and acetylation (H4K12ac) in common bean (Phaseolus vulgaris L.) under rust (Uromyces appendiculatus) stress using two high-throughput approaches, chromatin immunoprecipitation sequencing (ChIP-Seq) and RNA sequencing (RNA-Seq). ChIP-Seq analysis revealed 1,235 and 556 histone methylation and acetylation responsive genes from common bean leaves treated with the rust pathogen at 0, 12 and 84 hour-after-inoculation (hai), while …


Privacy-Preserving And Outsourced Multi-User K-Means Clustering, Bharath Samanthula, Fang-Yu Rao, Elisa Bertino, Xun Yi, Dangxi Liu Dec 2014

Privacy-Preserving And Outsourced Multi-User K-Means Clustering, Bharath Samanthula, Fang-Yu Rao, Elisa Bertino, Xun Yi, Dangxi Liu

Cyber Center Publications

Many techniques for privacy-preserving data mining (PPDM) have been investigated over the past decade. Often, the entities involved in the data mining process are end-users or organizations with limited computing and storage resources. As a result, such entities may want to refrain from participating in the PPDM process. To overcome this issue and to take many other benefits of cloud computing, outsourcing PPDM tasks to the cloud environment has recently gained special attention. We consider the scenario where n entities outsource their databases (in encrypted format) to the cloud and ask the cloud to perform the clustering task on their …


Poster: Protecting Against Data Exfiltration Insider Attacks Through Application Programs, Asmaa Mohamed Sallama, Elisa Bertino Nov 2014

Poster: Protecting Against Data Exfiltration Insider Attacks Through Application Programs, Asmaa Mohamed Sallama, Elisa Bertino

Cyber Center Publications

In this paper, we describe a system that distinguishes be- tween legitimate and malicious database transactions per- formed by application programs. Our system is particularly useful for protecting against code-modification attacks performed by insiders who have access to and can change the programs' source code to make them execute different queries than those they are expected to execute. Our system works with any type of DBMS and requires minimum modification to application programs.


An Efficient Certificateless Encryption For Secure Data Sharing In Public Clouds, Seung-Hyun Seo, Mohamed Yoosuf Mohamed Nabeel, Xiaoyu Ding, Elisa Bertino Sep 2014

An Efficient Certificateless Encryption For Secure Data Sharing In Public Clouds, Seung-Hyun Seo, Mohamed Yoosuf Mohamed Nabeel, Xiaoyu Ding, Elisa Bertino

Cyber Center Publications

We propose a mediated certificateless encryption scheme without pairing operations for securely sharing sensitive information in public clouds. Mediated certificateless public key encryption (mCL-PKE) solves the key escrow problem in identity based encryption and certificate revocation problem in public key cryptography. However, existing mCL-PKE schemes are either inefficient because of the use of expensive pairing operations or vulnerable against partial decryption attacks. In order to address the performance and security issues, in this paper, we first propose a mCL-PKE scheme without using pairing operations. We apply our mCL-PKE scheme to construct a practical solution to the problem of sharing sensitive …


Draft Genome Sequence Of Acetobacter Aceti Strain 1023, A Vinegar Factory Isolate, John Hung, Christopher Mill, Sandra Clifton, Vincent Magrini, Ketaki Bhide, Julie Francois, Aaron Ransome, Lucinda Fulton, Jyothi Thimmapuram, Richard Wilson, T. Joseph Kappock Jun 2014

Draft Genome Sequence Of Acetobacter Aceti Strain 1023, A Vinegar Factory Isolate, John Hung, Christopher Mill, Sandra Clifton, Vincent Magrini, Ketaki Bhide, Julie Francois, Aaron Ransome, Lucinda Fulton, Jyothi Thimmapuram, Richard Wilson, T. Joseph Kappock

Cyber Center Publications

The genome sequence of Acetobacter aceti 1023, an acetic acid bacterium adapted to traditional vinegar fermentation, comprises 3.0 Mb (chromosome plus plasmids). A. aceti 1023 is closely related to the cocoa fermenter Acetobacter pasteurianus 386B but possesses many additional insertion sequence elements.


A Practical Approach For Provenance Transmission In Wireless Sensor Networks, S.M. Iftekharul Alam, Sonia Fahmy May 2014

A Practical Approach For Provenance Transmission In Wireless Sensor Networks, S.M. Iftekharul Alam, Sonia Fahmy

Cyber Center Publications

Assessing the trustworthiness of sensor data and transmitters of this data is critical for quality assurance. Trust evaluation frameworks utilize data provenance along with the sensed data values to compute the trustworthiness of each data item. However, in a sizeable multi-hop sensor network, provenance information requires a large and variable number of bits in each packet, resulting in high energy dissipation due to the extended period of radio communication. In this paper, we design energy-efficient provenance encoding and construction schemes, which we refer to as Probabilistic Provenance Flow (PPF). Our work demonstrates the feasibility of adapting the Probabilistic Packet Marking …


Security Of Graph Data: Hashing Schemes And Definitions, Muhammad U. Arshad, Ashish Kundu, Elisa Bertino, Krishna Madhavan, Arif Ghafoor Mar 2014

Security Of Graph Data: Hashing Schemes And Definitions, Muhammad U. Arshad, Ashish Kundu, Elisa Bertino, Krishna Madhavan, Arif Ghafoor

Cyber Center Publications

Use of graph-structured data models is on the rise - in graph databases, in representing biological and healthcare data as well as geographical data. In order to secure graph-structured data, and develop cryptographically secure schemes for graph databases, it is essential to formally define and develop suitable collision resistant one-way hashing schemes and show them they are efficient. The widely used Merkle hash technique is not suitable as it is, because graphs may be directed acyclic ones or cyclic ones. In this paper, we are addressing this problem. Our contributions are: (1) define the practical and formal security model of …


Randomized And Efficient Authentication In Mobile Environments, Wei Jiang, Dan Lin, Feng Li, Elisa Bertino Feb 2014

Randomized And Efficient Authentication In Mobile Environments, Wei Jiang, Dan Lin, Feng Li, Elisa Bertino

Cyber Center Publications

In a mobile environment, a number of users act as a network nodes and communicate with one another to acquire location based information and services. This emerging paradigm has opened up new business opportunities and enables numerous applications such as road safety enhancement, service recommendations and mobile entertainment. A fundamental issue that impacts the success of these applications is the security and privacy concerns raised regarding the mobile users. In that, a malicious user or service provider can track the locations of a user traveled so that other malicious act can be carried out more effectively against the user. Therefore, …


Identidroid: Android Can Finally Wear Its Anonymous Suit, Bilal Shebaro, Oyindamola Oluwatimi, Daniele Midi, Elisa Bertino Jan 2014

Identidroid: Android Can Finally Wear Its Anonymous Suit, Bilal Shebaro, Oyindamola Oluwatimi, Daniele Midi, Elisa Bertino

Cyber Center Publications

Because privacy today is a major concern for mobile applications, network anonymizers are widely available on smartphones, such as Android. However despite the use of such anonymizers, in many cases applications are still able to identify the user and the device by different means than the IP address. The reason is that very often applications require device services and information that go beyond the capabilities of anonymous networks in protecting users’ identity and privacy. In this paper, we propose two solutions that address this problem. The first solution is based on an approach that shadows user and application data, device …


The Palm-Tree Index: Indexing With The Crowd, Aamer Mahmood, Walid G. Aref, Eduard Dragut, Saleh Basalamah Jan 2013

The Palm-Tree Index: Indexing With The Crowd, Aamer Mahmood, Walid G. Aref, Eduard Dragut, Saleh Basalamah

Cyber Center Publications

Crowdsourcing services allow employing human intelligence in tasks that are difficult to accomplish with computers such as image tagging and data collection. At a relatively low monetary cost and through web interfaces such as Amazon’s Mechanical Turk (AMT), humans can act as a computational operator in large systems. Recent work has been conducted to build database management systems that can harness the crowd power in database operators, such as sort, join, count, etc. The fundamental problem of indexing within crowdsourced databases has not been studied. In this paper, we study the problem of tree-based indexing within crowd-nabled databases. We investigate …


Lonomics Atlas: A Tool To Explore Interconnected Ionomic, Genomic And Environmental Data, Eduard Dragut, Amgad Madkour, Mohamed Nabeel, Peter Baker, Mourad Ouzzani, David Salt Oct 2012

Lonomics Atlas: A Tool To Explore Interconnected Ionomic, Genomic And Environmental Data, Eduard Dragut, Amgad Madkour, Mohamed Nabeel, Peter Baker, Mourad Ouzzani, David Salt

Cyber Center Publications

Ionomics Atlas facilitates access, analysis and interpretation of an existing large-scale heterogeneous dataset consisting of ionomic (elemental composition of an organism), ge- netic (heritable changes in the DNA of an organism) and ge- ographic information (geographic location, altitude, climate, soil properties, etc). Ionomics Atlas allows connections to be made between the genetic regulation of the ionome of plant populations and their landscape distribution, allowing scientists to investigate the role of natural ionomic variation in adaptation of populations to varied environmental conditions in the landscape. The goal of the Ionomics Atlas is twofold: (1) to allow both novice and expert users …


The Bench Scientist's Guide To Statistical Analysis Of Rna-Seq Data, Craig R. Yendrek, Elizabeth A. Ainsworth, Jyothi Thimmapuram Sep 2012

The Bench Scientist's Guide To Statistical Analysis Of Rna-Seq Data, Craig R. Yendrek, Elizabeth A. Ainsworth, Jyothi Thimmapuram

Cyber Center Publications

RNA sequencing (RNA-Seq) is emerging as a highly accurate method to quantify transcript abundance. However, analyses of the large data sets obtained by sequencing the entire transcriptome of organisms have generally been performed by bioinformatics specialists. Here we provide a step-by-step guide and outline a strategy using currently available statistical tools that results in a conservative list of differentially expressed genes. We also discuss potential sources of error in RNA-Seq analysis that could alter interpretation of global changes in gene expression.


Whole-Genome Resequencing Of Two Elite Sires For The Detection Of Haplotypes Under Selection In Dairy Cattle Supporting Information, Denis M. Larkin, Hans D. Daetwyler, Alvaro G. Hernandez, Chris L. Wright, Lorie A. Hetrick, Lisa Boucek, Sharon Bachman, Jyothi Thimmapuram Mar 2012

Whole-Genome Resequencing Of Two Elite Sires For The Detection Of Haplotypes Under Selection In Dairy Cattle Supporting Information, Denis M. Larkin, Hans D. Daetwyler, Alvaro G. Hernandez, Chris L. Wright, Lorie A. Hetrick, Lisa Boucek, Sharon Bachman, Jyothi Thimmapuram

Cyber Center Publications

Using a combination of whole-genome resequencing and high-density genotyping arrays, genome-wide haplotypes were reconstructed for two of the most important bulls in the history of the dairy cattle industry, Pawnee Farm Arlinda Chief (“Chief”) and his son Walkway Chief Mark (“Mark”), each accounting for ∼7% of all current genomes. We aligned 20.5 Gbp (∼7.3× coverage) and 37.9 Gbp (∼13.5× coverage) of the Chief and Mark genomic sequences, respectively. More than 1.3 million high-quality SNPs were detected in Chief and Mark sequences. The genome-wide haplotypes inherited by Mark from Chief were reconstructed using ∼1 million informative SNPs. Comparison of a set …


Artl@ S And Basart: A Loose Coupling Strategy For Digital Humanities, Sorin Matei Jan 2012

Artl@ S And Basart: A Loose Coupling Strategy For Digital Humanities, Sorin Matei

Cyber Center Publications

The core ARTL@S digital humanities
strategy is that of loosely coupling
resources, platforms, and use scenarios.
A number of sites will feed from
the same geodatabase (BasArt),
which will be enriched by users with
new content. Inspired by the Web 2.0
design principles, ARTL@S relies on
the BasArt API, which will enable an
ecosystem of sites to use primary
data to generate their own maps,
charts, and tables. A variety of economic
models will also be used to
support the site, from free to paybased.
User-generated content will be
monitored by data management and
curation techniques that will ensure
the …


Authenticated Top-K Aggregation In Distributed And Authenticated Top-K Aggregation In Distributed And, Sunoh Choi, Hyo-Sang Lim, Elisa Bertino Jan 2012

Authenticated Top-K Aggregation In Distributed And Authenticated Top-K Aggregation In Distributed And, Sunoh Choi, Hyo-Sang Lim, Elisa Bertino

Cyber Center Publications

Top-k queries have attracted interest in many different areas like network and system monitoring, information retrieval, sensor networks, and so on. Since today many applications issue top-k queries on distributed and outsourced databases,
authentication of top-k query results becomes more important. This paper addresses the problem of authenticated top-k aggregation queries (e.g. “find the k objects with the highest aggregate values”) in a distributed system. We propose a new algorithm, called Authenticated Three Phase Uniform Threshold (A-TPUT), which provides not only efficient top-k aggregation over distributed databases but also authentication on the top-k results. We also introduce several enhancements for …


Transcriptome Sequencing Of The Blind Subterranean Mole Rat, Spalax Galili: Utility And Potential For The Discovery Of Novel Evolutionary Patterns, Assaf Malik, Abraham Korol, Sariel Hubner, Aaron Avivi, Alvaro Hernandez, Jyothi Thimmapuram, Shahjahan Ali, Mark Bond, Fabian Glaser, Arnon Paz Aug 2011

Transcriptome Sequencing Of The Blind Subterranean Mole Rat, Spalax Galili: Utility And Potential For The Discovery Of Novel Evolutionary Patterns, Assaf Malik, Abraham Korol, Sariel Hubner, Aaron Avivi, Alvaro Hernandez, Jyothi Thimmapuram, Shahjahan Ali, Mark Bond, Fabian Glaser, Arnon Paz

Cyber Center Publications

The blind subterranean mole rat (Spalax ehrenbergi superspecies) is a model animal for survival under extreme environments due to its ability to live in underground habitats under severe hypoxic stress and darkness. Here we report the transcriptome sequencing of Spalax galili, a chromosomal type of S. ehrenbergi. cDNA pools from muscle and brain tissues isolated from animals exposed to hypoxic and normoxic conditions were sequenced using Sanger, GS FLX, and GS FLX Titanium technologies. Assembly of the sequences yielded over 51,000 isotigs with homology to ~12,000 mouse, rat or human genes. Based on these results, it was …


Orchardgrass (Dactylis Glomerata L.) Est And Ssr Marker Development, Annotation, And Transferability., B.S. Bushman, S.R. Larson, M Tuna, M.S. West, A.G. Hernandez, D Vullaganti, G Gong, J.G. Robbins, K. B. Jensen, Jyothi Thimmapuram Apr 2011

Orchardgrass (Dactylis Glomerata L.) Est And Ssr Marker Development, Annotation, And Transferability., B.S. Bushman, S.R. Larson, M Tuna, M.S. West, A.G. Hernandez, D Vullaganti, G Gong, J.G. Robbins, K. B. Jensen, Jyothi Thimmapuram

Cyber Center Publications

Orchardgrass, or cocksfoot [Dactylis glomerata (L.)], has been naturalized on nearly every continent and is a commonly used species for forage and hay production. All major cultivated varieties of orchardgrass are autotetraploid, and few tools or information are available for functional and comparative genetic analyses and improvement of the species. To improve the genetic resources for orchardgrass, we have developed an EST library and SSR markers from salt, drought, and cold stressed tissues. The ESTs were bi-directionally sequenced from clones and combined into 17,373 unigenes. Unigenes were annotated based on putative orthology to genes from rice, Triticeae grasses, other Poaceae, …


Identification And Analysis Of Common Bean (Phaseolus Vulgaris L.) Transcriptomes By Massively Parallel Pyrosequencing, Venu Kalavacharla, Zhanji Liu, Blake C. Meyers, Jyothi Thimmapuram, Kalpalatha Melmaiee Jan 2011

Identification And Analysis Of Common Bean (Phaseolus Vulgaris L.) Transcriptomes By Massively Parallel Pyrosequencing, Venu Kalavacharla, Zhanji Liu, Blake C. Meyers, Jyothi Thimmapuram, Kalpalatha Melmaiee

Cyber Center Publications

Common bean (Phaseolus vulgaris) is the most important food legume in the world. Although this crop is very important to both the developed and developing world as a means of dietary protein supply, resources available in common bean are limited. Global transcriptome analysis is important to better understand gene expression, genetic variation, and gene structure annotation in addition to other important features. However, the number and description of common bean sequences are very limited, which greatly inhibits genome and transcriptome research. Here we used 454 pyrosequencing to obtain a substantial transcriptome dataset for common bean.


Privacy-Preserving Assessment Of Location Data Trustworthiness, Chenyun Dai, Fang-Yu Rao, Gabriel Ghinita, Elisa Bertino Jan 2011

Privacy-Preserving Assessment Of Location Data Trustworthiness, Chenyun Dai, Fang-Yu Rao, Gabriel Ghinita, Elisa Bertino

Cyber Center Publications

Assessing the trustworthiness of location data corresponding to individuals is essential in several applications, such as forensic science and epidemic control. To obtain accurate and trustworthy location data, analysts must often gather and correlate information from several independent sources, e.g., physical observation, witness testimony, surveillance footage, etc. However, such information may be fraudulent, its accuracy may be low, and its vol-
ume may be insufficient to ensure highly trustworthy data. On the other hand, recent advancements in mobile computing and positioning systems, e.g., GPS-enabled cell phones, highway sensors, etc., bring new and effective technological means to track the location of …


Prox-Rbac: A Proximity-Based Spatially Aware Rbac, Michael Kirkpatrick, Maria Luisa Damiani, Elisa Bertino Jan 2011

Prox-Rbac: A Proximity-Based Spatially Aware Rbac, Michael Kirkpatrick, Maria Luisa Damiani, Elisa Bertino

Cyber Center Publications

As mobile computing devices are becoming increasingly dominant in enterprise and government organizations, the need for fine-grained access control in these environments continues to grow. Specifically, advanced forms of access control can be deployed to ensure authorized users can access sensitive resources only when in trusted locations. One technique that has been proposed is to augment role-based access control (RBAC) with spatial constraints. In such a system, an authorized user must be in a designated location in order to exercise the privileges associated with a role. In this work, we extend spatially aware RBAC systems by defining the notion of …


Endogenous Sirnas And Noncoding Rna-Derived Small Rnas Are Expressed In Adult Mouse Hippocampus And Are Up-Regulated In Olfactory Discrimination Training., Neil Smalheiser, G Lugli, Jyothi Thimmapuram, E.H. Cook, J Larson Nov 2010

Endogenous Sirnas And Noncoding Rna-Derived Small Rnas Are Expressed In Adult Mouse Hippocampus And Are Up-Regulated In Olfactory Discrimination Training., Neil Smalheiser, G Lugli, Jyothi Thimmapuram, E.H. Cook, J Larson

Cyber Center Publications

We previously proposed that endogenous siRNAs may regulate synaptic plasticity and long-term gene expression in the mammalian brain. Here, a hippocampal-dependent task was employed in which adult mice were trained to execute a nose-poke in a port containing one of two simultaneously present odors in order to obtain a reward. Mice demonstrating olfactory discrimination training were compared to pseudo-training and nose-poke control groups; size-selected hippocampal RNA was subjected to Illumina deep sequencing. Sequences that aligned uniquely and exactly to the genome without uncertain nucleotide assignments, within exons or introns of MGI annotated genes, were examined further. The data confirm that …


A Visual Analytics Approach To Understanding Spatiotemporal Hotspots, Ross Maciejewski, Stephen Rudolph, Ryan Hafen, Ahmad Abusalah, Mohamed Yakout, Mourad Ouzzani, William S. Cleveland, Shaun Grannis, David S. Ebert Jan 2010

A Visual Analytics Approach To Understanding Spatiotemporal Hotspots, Ross Maciejewski, Stephen Rudolph, Ryan Hafen, Ahmad Abusalah, Mohamed Yakout, Mourad Ouzzani, William S. Cleveland, Shaun Grannis, David S. Ebert

Cyber Center Publications

As data sources become larger and more complex, the ability to effectively explore and analyze patterns amongst varying sources becomes a critical bottleneck in analytic reasoning. Incoming data contains multiple variables, high signal to noise ratio, and a degree of uncertainty, all of which hinder exploration, hypothesis eneration/exploration, and decision making. To facilitate the exploration of such data, advanced tool sets are needed that allow the user to interact with their data in a visual environment that provides direct analytic capability for finding data aberrations or hotspots. In this paper, we present a suite of tools designed to facilitate the …


A Database Server For Next-Generation Scientific Data Management, Mohamed Eltabakh, Walid G. Aref, Ahmed Elmagarmid Jan 2010

A Database Server For Next-Generation Scientific Data Management, Mohamed Eltabakh, Walid G. Aref, Ahmed Elmagarmid

Cyber Center Publications

The growth of scientific information and the increasing automation of data collection have made databases integral to many scientific disciplines including life sciences, physics, meteorology, earth and atmospheric sciences, and chemistry. These sciences pose new data management challenges to current database system technologies. This dissertation addresses the following three challenges: (1) Annotation Management: Annotations and provenance information are important metadata that go hand-in-hand with scientific data. Annotating scientific data represents a vital mechanism for scientists to share knowledge and build an interactive and collaborative environment. A major challenge is: How to manage large volumes of annotations, especially at various granularities, …


Spatio-Temporal Access Methods: Part 2 (2003 - 2010), Long-Van Nguyen-Dinh, Walid G. Aref, Mohamed Mokbel Jan 2010

Spatio-Temporal Access Methods: Part 2 (2003 - 2010), Long-Van Nguyen-Dinh, Walid G. Aref, Mohamed Mokbel

Cyber Center Publications

In spatio-temporal applications, moving objects detect their locations via location-aware devices and update their locations continuously to the server. With the ubiquity and massive numbers of moving objects, many spatio-temporal access methods are developed to process user queries efficiently. Spatio- temporal access methods are classified into four categories: (1) Indexing the past data, (2) Indexing the current data, (3) Indexing the future data, and (4) Indexing data at all points of time. This short survey is Part 2 of our previous work [28]. In Part 2, we give an overview and classification of spatio-temporal access methods that are published between …


Privometer: Privacy Protection In Social Networks, Nilothpal Talukder, Mourad Ouzzani, Ahmed Elmagarmid, Hazem Elmeleegy Jan 2010

Privometer: Privacy Protection In Social Networks, Nilothpal Talukder, Mourad Ouzzani, Ahmed Elmagarmid, Hazem Elmeleegy

Cyber Center Publications

The increasing popularity of social networks, such as Facebook and Orkut, has raised several privacy concerns. Traditional ways of safeguarding privacy of personal information by hiding sensitive attributes are no longer adequate. Research shows that probabilistic classification techniques can effectively infer such private information. The disclosed sensitive information of friends, group affiliations and even participation in activities, such as tagging and commenting, are considered background knowledge in this process. In this paper, we present a privacy protection tool, called Privometer, that measures the amount of sensitive information leakage in a user profile and suggests selfsanitization actions to regulate the amount …


Online Piece-Wise Linear Approximation Of Numerical Streams With Precision Guarantees, Hazem Elmeleegy, Ahmed Elmagarmid, Emmanuel Cecchet, Walid G. Aref, Willy Zwaenepoel Aug 2009

Online Piece-Wise Linear Approximation Of Numerical Streams With Precision Guarantees, Hazem Elmeleegy, Ahmed Elmagarmid, Emmanuel Cecchet, Walid G. Aref, Willy Zwaenepoel

Cyber Center Publications

Continuous “always-on” monitoring is beneficial for a number of applications, but potentially imposes a high load in terms of communication, storage and power consumption when a large number of variables need to be monitored. We introduce two new filtering techniques, swing filters and slide filters, that represent within a prescribed precision a time-varying numerical signal by a piecewise linear function, consisting of connected line segments for swing filters and (mostly) disconnected line segments for slide filters. We demonstrate the effectiveness of swing and slide filters in terms of their compression power by applying them to a reallife data set plus …


Diversity And Strain Specificity Of Plant Cell Wall Degrading Enzymes Revealed By The Draft Genome Of Ruminococcus Flavefaciens Fd-1, Margret E. Berg Miller, Dionysios A. Antonopoulos, Mark Brand, Albert Bari, Alvaro Hernandez, Jyothi Thimmapuram, Bryan A. White, Marco Rincon, Harry J. Flint, Bernard Henrissat, Pedro M. Coutinho Aug 2009

Diversity And Strain Specificity Of Plant Cell Wall Degrading Enzymes Revealed By The Draft Genome Of Ruminococcus Flavefaciens Fd-1, Margret E. Berg Miller, Dionysios A. Antonopoulos, Mark Brand, Albert Bari, Alvaro Hernandez, Jyothi Thimmapuram, Bryan A. White, Marco Rincon, Harry J. Flint, Bernard Henrissat, Pedro M. Coutinho

Cyber Center Publications

Ruminococcus flavefaciens is a predominant cellulolytic rumen bacterium, which forms a multi-enzyme cellulosome complex that could play an integral role in the ability of this bacterium to degrade plant cell wall polysaccharides. Identifying the major enzyme types involved in plant cell wall degradation is essential for gaining a better understanding of the cellulolytic capabilities of this organism as well as highlighting potential enzymes for application in improvement of livestock nutrition and for conversion of cellulosic biomass to liquid fuels.


Generalization Of Acid Properties, Brahim Medjahed, Mourad Ouzzani, Ahmed Elmagarmid Jan 2009

Generalization Of Acid Properties, Brahim Medjahed, Mourad Ouzzani, Ahmed Elmagarmid

Cyber Center Publications

ACID (Atomicity, Consistency, Isolation, and Durability) is a set of properties that guarantee the reliability of database transactions [2]. ACID properties were initially developed with traditional, business-oriented applications (e.g., banking) in mind. Hence, they do not fully support the functional and performance requirements of advanced database applications such as computer-aided design, computer-aided manufacturing, office automation, network management, multidatabases, and mobile databases. For instance, transactions in computer-aided design applications are generally of long duration and preserving the traditional ACID properties in such transactions would require locking resources for long periods of time. This has lead to the generalization of ACID properties …


Beyond K-Anonymity: A Decision Theoretic Framework For Assessing Privacy Risk, Guy Lebanon, Monica Scannapieco, Mohamed Fouad, Elisa Bertino Jan 2009

Beyond K-Anonymity: A Decision Theoretic Framework For Assessing Privacy Risk, Guy Lebanon, Monica Scannapieco, Mohamed Fouad, Elisa Bertino

Cyber Center Publications

An important issue any organization or individual has to face when managing data containing sensitive information, is the risk that can be incurred when releasing such data. Even though data may be sanitized before being released, it is still possible for an adversary to reconstruct the original data using additional information thus resulting in privacy violations. To date, however, a systematic approach to quantify such risks is not available. In this paper we develop a framework, based on statistical decision theory, that assesses the relationship between the disclosed data and the resulting privacy risk. We model the problem of deciding …