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[EB 2011, Fellows]
No full text[Title supplied by cataloger]AAA Awards Banquet at the 2011 Experimental Biology conference. 2011 Fellows. Seated: A. J. Ladman, Vivien Casagrande, Gwendolyn Childs, Scott Lozanoff. Standing: Bjorn Olsen, Dennis Stelzner, Lynne Opperman, Takashi Mikawa, Dallas Hyde
[EB 2011, Young Investigator Awards Symposium]
No full text[Title supplied by cataloger]Konrad Hochedlinger delivering the Mossman Award Lecture at the Young Investigator Awards Symposium, Experimental Biology 2011
Exploiting Architectural Techniques for Boosting Base Station Anonymity in Wireless Sensor Networks
No full textWireless Sensor Networks (WSNs) can be deployed to serve mission-critical applications in hostile environments such as battlefield and territorial borders. In these setups, the WSN may be subject to attacks in order to disrupt the network operation. The most effective way for an adversary to do so is by targeting the Base-Station (BS), where the sensor data are collected in the field. By identifying and locating the BS, the adversary can launch attacks to damage or disrupt the operation of the BS. Therefore, maintaining the BS anonymity is of utmost importance in WSNs. In this thesis we propose three novel approaches to boost the anonymity of the BS nodes to protect them from potential threats. We first explore the deployment of more BS nodes. We compare the BS anonymity of one versus multiple stationary BS under different network topologies. Our results show that having more base-stations can boost both the average and max anonymity of BS nodes. We further provide guidelines on a cost versus anonymity trade-off to determine the most suitable BS count for a network. Second we exploit the mobility of base-stations and explore the effect of relocating some of the existing BS nodes to the lowest anonymity regions. Our results show that having one mobile BS can dramatically boost the anonymity of the network and moving multiple BS does not provide much value. Finally, we propose to pursue dynamic sensor to cluster re-association to confuse the adversary. This can be employed when base-stations cannot safely move
ALBS: AN ADPATIVE LOAD BALANCING SYSTEM IN MAPREDUCE
No full textMapReduce is a popular parallel programming model used in large-scale data processing applications running on a cluster computer. MapReduce has two main functions: Map and Reduce. Map function transforms the data into the key-value format on each node and Reduce function merges the values associated with the same key from the different nodes. However, typical MapReduce implementations have the imbalance issue of load (the number of key-value pairs). This thesis proposes an Adaptive Load Balancing Algorithm to balance the load and implements it in X10. The systematic experimental results show that this algorithm enables a good load balances, reduces communication across compute nodes, and consequently improves overall performance
For the Sake of Oil, For the Sake of Prestige or For the Sake of Power: Did Cooperation among the Governments of the United States and Great Britain Contribute to the 1953 Coup of Iran?
No full textDuring the Cold War, when a wave of nationalism was spreading around in Asia and the Middle East, the nationalist government of Dr. Mohammad Mossadegh was overthrown by foreign and internal elements in the coup of 1953. This work uncovers the events of the overthrow with respect to the Cold War context. The fear of communism resulted in hysteria and the hyperbolic perspective of the Eisenhower Administration toward nationalist movements during the Cold War era. This work combines both old and new historical trends in order to reconstruct the events of the coup of 1953 and examines all the external and internal factors that contributed to the coup. The study uncovers all governmental and non-governmental actors who collaborated together to conduct the coup. The thesis examines the U.S.' traditional alliance with Great Britain, Britain's overplaying the U.S.' Cold War hysteria, corporations and their use of the intelligence service in conducting foreign policy, and the role of adventuresome men who shaped the policy process in Iran in 1953. By relying on Farsi and English documents, interviews, and newspapers, oral histories from the Harvard Iranian Project, documents from the International Court of Justice, speeches of Dr. Mossadegh, memoirs of policymakers and intelligence service officers, and treaties signed between Iran and the United States after the coup, this study provides insight into understanding a missed opportunity for Iran that continues to color U.S.-Iranian relations today
Towards Relational Theory Formation from Undifferentiated Sensor Data
No full textHuman adults have rich theories in their heads of how the world works. These theories include objects and relations for both concrete and abstract concepts. Everything we know either must be innate or learned through experience. Yet it's unclear how much of this model needs to be innate for a computer. The core question this dissertation addresses is how a computer can develop rich relational theories using only its raw sensor data. We address this by outlining a bridge between raw sensors and a rich relational theory. We have implemented parts of this bridge, with other parts as feasibility studies, while others remain conceptual. At the core of this bridge is Ontol, a system that constructs a conceptual structure or ontology from feature-set data. Ontol is inspired by cortical models that have been shown to be able to express invariant concepts, such as images independent of any translation or rotation. As a demonstration of the utility of the ontologies created by Ontol, we present a novel semi-supervised learning algorithm that learns from only a handful of positive examples. Like humans, this algorithm doesn't require negative examples. Instead, this algorithm uses the ontologies created by Ontol from unlabeled data, and searches for a Bayes-optimal theory given this background knowledge. The rest of the dissertation shows in principle how Ontol can be used as the workhorse for a system that finds analogies, discovers useful mappings, and might ultimately create theories, such as a gisty theory of number
WAC Voices: The Transition of the Women's Army Corps into the Integrated Army, 1973-1978
No full textIn order to attract volunteers after the end of the draft in 1973, the Army began an intensive advertising campaign aimed at young women. In these ads the Army promoted itself as the ultimate equal opportunity employer -- something not always available in the civilian world. However, these advertisements implied that the Army was just another employer competing for competent applicants. What the ads failed to acknowledge is that the Army is not a job, but a culture, and a masculine one at that. What was it like for these women to suddenly find themselves members of the biggest men's club in the world? And would women find true equal opportunity in this man's Army? In an effort to answer that question, the research contains oral history interviews conducted with women who served in the Army during 1973-1978 transition period
DISPARITIES IN EMPLOYER-BASED HEALTH INSURANCE COVERAGE FOR WORKING-AGE INDIVIDUALS WITH DISABILITIES
No full textEvidence has shown that improving public health services, access to a usual source of care, health insurance coverage, and improving the quality of health services are all important strategies to overcome disparities for the larger population. However, to date, scarce research is available which examines these issues for individuals with disabilities. This study focuses on the question of employer sponsored insurance (ESI) coverage through the current main job (CMJ) for individuals with disabilities. Using the 2003-2007 Medical Expenditure Panel Survey Household Component data files, the study sample consisted of working-age adults (aged 18-64) who were employed at least part time during the year of reference (n=62,970). Two research questions were examined: (a) among people with disabilities who are employed, what is the likelihood of having ESI coverage through the CMJ, relative to people without disabilities; and (b) what are the predictors of having ESI insurance through their CMJ; specifically, to what extent does the nature of the disability, individual sociodemographic characteristics, and characteristics of the job/employer predict the likelihood that an employee will have ESI through his/her main job? Multivariate analyses were conducted to evaluate how well each of four models (disability; disability and demographics; disability, demographics, and employment characteristics; and disability, demographics, employment characteristics, and firm characteristics) predicted the dependent variable of health insurance held through the CMJ. Study findings demonstrated that the presence of ESI through the CMJ was significantly associated with the type of disability, as individuals with certain disabilities had lower odds of holding employer-based coverage through the CMJ when unadjusted for sociodemographic and firm characteristics. However, study findings showed that physical limitations remained the only significant disability category when all individual sociodemographic, firm, and employment characteristics were incorporated in the final model comparing individuals with and without disabilities. Among individuals with disabilities, those with functional limitations had lower odds of having ESI through their CMJ, relative to the reference group of individuals with work limitations. Research results indicate that more complete models are needed to explain disparities in ESI coverage through the CMJ and the complex relationships among disabilities, firm, employment, and demographic characteristics
AN ECONOMIC ANALYSIS OF AIRPORT BAGGAGE ROUTING AND AIRLINE SECURITY
No full textA significant portion of American Airlines (AA) and American Eagle (AE) financial loss experienced at Washington Reagan National Airport (DCA) in the past years is due to the inefficiency in baggage handling, routing processes and associated security costs at DCA. The objective of this thesis is to analyze the impact of Information Technology (IT) on airport baggage routing and security. Based on an economic analysis of the detailed AA and AE daily baggage traffic flows and baggage routing process data we collected at DCA, we not only identified several areas of operational inefficiency in the baggage handling process, but also quantified the benefit of IT investment in improving the process efficiency. These findings provide important insights into major areas of inefficiency and technology investment in the baggage handling operations by American Airlines. We also generalize our findings to make applicable suggestions and practical recommendations on baggage issues for the aviation industry
Regulation of the Non-image Forming Photopigment Melanopsin by Phosphorylation
No full textMelanopsin is an atypical vertebrate visual pigment expressed in a subset of retinal ganglion cells in the mammalian retina. Melanopsin-based phototransduction is involved in non-image forming light responses including circadian photo-entrainment, pupil constriction, suppression of pineal melatonin synthesis, and direct photic regulation of sleep in vertebrates. Phosphorylation is the most common post-translational modification of proteins. The addition of a phosphate group to either a serine, threonine or tyrosine can cause a variety of changes in a protein. These include activation or inhibition of protein function, changes in protein structure and changes in the protein's interactions with other molecules. This work explores some of the ways in which melanopsin is regulated by phosphorylation. I have determined that mouse melanopsin is phosphorylated in a light-dependent manner and that this phosphorylation is involved in the deactivation of the signaling response. This phosphorylation was demonstrated in vitro, in heterologous expression systems and in vivo. I have also shown that the G protein coupled receptor kinase 2 (GRK2) is the best candidate kinase for phosphorylation in a heterologous expression system. I characterized the members of the GRK family expressed in melanopsin-expressing retinal ganglion cells to determine the endogenous kinase candidates. I then identified six sites in the cytoplasmic carboxy tail that are important for this phosphorylation by mutational analysis. The importance of these sites was also shown by characterization of the naturally diverse zebrafish melanopsins. Additionally, I demonstrated that protein kinase A (PKA) mediated phosphorylation of melanopsin occurs in both a heterologous expression system and in vivo. These phosphorylations were localized to the intracellular loops of melanopsin by mutational and functional analysis. Phosphorylation of these sites was shown to be involved in inhibiting melanopsin signaling in HEK293 cells. I hypothesize that phosphorylation of melanopsin by PKA is a form of circadian regulation of melanopsin function