Advanced microstructured platforms for neuroscience: from lab-on-chips for circadian clock studies to next generation bionic 3D brain tissue models

In mammals, the suprachiasmatic nucleus (SCN) of the hypothalamus is considered the master circadian pacemaker which coordinates circadian rhythms in the central nervous system (CNS) and across the entire body. The SCN receives light input from the eyes through the retinohypothalamic tract and then it synchronizes other clocks in the CNS and periphery, thus orchestrating rhythms throughout the body. However, little is known about how so many cellular clocks within and across brain circuits can be effectively synchronized to entrain the coordinated expression of clock genes in cells distributed all over the brain. In this work I investigated the possible implication of two possible pathways: i) paracrine factors-mediated synchronization and ii) astrocytes-mediated synchronization. To study these pathways, I adopted an in vitro research model that I developed based on a lab-on-a-chip microfluidic device designed and realized in our laboratory. This device allows growing and compartmentalizing distinct neural populations connected through a network of astrocytes or through a cell-free channel in which the diffusion of paracrine factors is allowed. By taking advantage of this device, upon its validation, I synchronized neural clocks in one compartment and analyzed, in different experimental conditions, the induced expression of clock genes in a distant neural network grown in the second compartment. Results show that both pathways can be involved, but might have different roles. Neurons release factors that can diffuse to synchronize a neuronal population. The same factors can also synchronize astrocytes that, in turn, can transmit astrocyte-mediated molecular clocks to more distant neuronal populations. This is supported by experimental data obtained using microfluidic devices featuring different channel lengths. I found that paracrine factors-mediated synchronization occurs only in the case of a short distance between neuronal populations. On the contrary, interconnecting astrocytes define an active channel that can transfer molecular clocks to neural populations also at long distances. The study of possibly involved signaling factors indicate that paracrine factors-mediated synchronization occurs through GABA signaling, while astrocytes-mediated synchronization involves both GABA and glutamate. These findings strength the importance of the synergic regulation of clock genes among neurons and astrocytes, and identify a previously unknown role of astrocytes as active cells in distributing signals to regulate the expression of clock genes in the brain. Preliminary results also show a correlation between astrocyte reactivity and local alterations in neuronal synchronization, thus opening a new scenario for future studies in which disease-induced astrocyte reactivity might be linked to alterations in clock gene expression.Three-dimensional (3D) brain models hold great potential for the generation of functional in vitro models to advance studies on human brain development, diseases and possible therapies. The routine exploitation of such models, however, is hindered by the lack of technologies to chronically monitor the activity of neural aggregates in three dimensions. A promising new approach consists in growing bio-artificial 3D brain model systems with seamless tissue-integrated biosensing artificial microdevices. Such devices could provide a platform for in-tissue sensing of diverse biologically relevant parameters. To date there is very little information on how to control the extracellular integration of such microscale devices into neuronal 3D cell aggregates. In this direction, in the present work I contributed to investigated the growth of hybrid neurospheroids obtained by the aggregation of silicon sham microchips (100x100x50\u3bcm3) with primary cortical cells. Interestingly, by coating microchips with different adhesion-promoting molecules, we reveal that surface functionalization can tune the integration and final 3D location of self-standing microdevices into neurospheroids. Morphological and functional characterization suggests that the presence of an integrated microdevice does not alter spheroid growth, cellular composition, nor network activity and maturation. Finally, we also demonstrate the feasibility of separating cells and microchips from formed hybrid neurospheroids for further single-cell analysis, and quantifications confirm an unaltered ratio of neurons and glia. These results uncover the potential of surface-engineered self-standing microdevices to grow untethered three-dimensional brain-tissue models with inbuilt bioelectronic sensors at predefined sites

Motion tracking problems in Internet of Things (IoT) and wireless networking

The dissertation focuses on inferring various motion patterns of internet-of-things (IoT) devices, by leveraging inertial sensors embedded in these objects, as well as wireless signals emitted (or reflected) from them. For instance, we use a combination of GPS signals and inertial sensors on drones to precisely track its 3D orientation over time, ultimately improving safety against failures and crashes. In another application in sports analytics, we embed sensors and radios inside baseballs and cricket balls and compute their 3D trajectory and spin patterns, even when they move at extremely high speeds. In a third application for wireless networks, we explore the possibility of physically moving wireless infrastructure like Access Points and basestations on robots and drones for enhancing the network performance. While these are diverse applications in drones, sports analytics, and wireless networks, the common theme underlying the research is in the development of the core motion-related building blocks. Specifically, we emphasize the philosophy of "fusion of multi modal sensor data with application specific model” as the design principle for building the next generation of diverse IoT applications. To this end, we draw on theoretical techniques in wireless communication, signal processing, and statistics, but translate them to completely functional systems on real-world platforms

Comparison of sea-ice freeboard distributions from aircraft data and cryosat-2

The only remote sensing technique capable of obtain- ing sea-ice thickness on basin-scale are satellite altime- ter missions, such as the 2010 launched CryoSat-2. It is equipped with a Ku-Band radar altimeter, which mea- sures the height of the ice surface above the sea level. This method requires highly accurate range measure- ments. During the CryoSat Validation Experiment (Cry- oVEx) 2011 in the Lincoln Sea, Cryosat-2 underpasses were accomplished with two aircraft, which carried an airborne laser-scanner, a radar altimeter and an electro- magnetic induction device for direct sea-ice thickness re- trieval. Both aircraft flew in close formation at the same time of a CryoSat-2 overpass. This is a study about the comparison of the sea-ice freeboard and thickness dis- tribution of airborne validation and CryoSat-2 measure- ments within the multi-year sea-ice region of the Lincoln Sea in spring, with respect to the penetration of the Ku- Band signal into the snow

Using MapReduce Streaming for Distributed Life Simulation on the Cloud

Distributed software simulations are indispensable in the study of large-scale life models but often require the use of technically complex lower-level distributed computing frameworks, such as MPI. We propose to overcome the complexity challenge by applying the emerging MapReduce (MR) model to distributed life simulations and by running such simulations on the cloud. Technically, we design optimized MR streaming algorithms for discrete and continuous versions of Conway’s life according to a general MR streaming pattern. We chose life because it is simple enough as a testbed for MR’s applicability to a-life simulations and general enough to make our results applicable to various lattice-based a-life models. We implement and empirically evaluate our algorithms’ performance on Amazon’s Elastic MR cloud. Our experiments demonstrate that a single MR optimization technique called strip partitioning can reduce the execution time of continuous life simulations by 64%. To the best of our knowledge, we are the first to propose and evaluate MR streaming algorithms for lattice-based simulations. Our algorithms can serve as prototypes in the development of novel MR simulation algorithms for large-scale lattice-based a-life models.https://digitalcommons.chapman.edu/scs_books/1014/thumbnail.jp

Technical Sensoriums: A Speculative Investigation into the Entanglement and Convergence of Surveillance and Technology

Surveillance and technology are among the most prevalent phenomena in the developed world, the proliferation of which is abetted by an ever increasing profusion of products and services extending the competencies of these capabilities into new opportunities and markets worldwide. More significantly, this momentum is leading to a convergence of these disparate competencies towards a common techno-surveillant milieu. Yet much of what is written and theoretically understood about these topics (singularly and collectively) fails to provide for a unified accounting that anticipates either the trajectory or the heterogeneous forms of this converging phenomenon. This projects sets out to excavate why our understanding of techno-surveillance is so myopic. Following the evidence, I assert that this short-sightedness is not simply the result of methodological shortcomings. Rather, most researchers of surveillance and technology are blinded by philosophical presumptions (primarily grounded in epistemology) that exclude the kinds of questions (largely ontological) they must ask to go deeper in their investigations. This study examines the archaeological detritus of an early techno-surveillant system, the characteristics of which are typical of the kinds of systems that have come to challenge researchers about the implications of their analyses. Based on this analysis, this study proposes an ontological model, which I call ontigeny that is consistent with the evidence and helps to explain the heterogeneity of techno-surveillance, as well as its potential trajectories

“We’ve Tamed the World by Framing It”: Islam, ‘Justifiable Warfare,’ and situational responses to the war on terror in selected post-9/11 novels, films and television

This thesis explores geopolitically diverse fictional responses to 9/11 and the War on Terror. Drawing on Judith Butler’s (2009) notion of the “frames of war,” Jacques Derrida’s (2005) conception of the ‘friend’/‘enemy’ binary, and Mahmood Mamdani’s (2004) critique of the ‘good’ Muslim, ‘bad’ Muslim dichotomy (delineated in 2001 by President George W. Bush) I examine how selected examples of contemporary literature, as well as a popular television series, depict the War on Terror; and analyse how these differently situated texts structure their respective depictions of Islam and Muslims. In the first chapter, I focus on how The Reluctant Fundamentalist (2007), a novel by the Pakistani author, Mohsin Hamid, problematises the ‘good’ Muslim, ‘bad’ Muslim binary, and argue that the protagonist’s decision to leave the United States in the wake of 9/11 represents an important political comment on global perceptions of American foreign policy and the human cost of millennial capitalism. Chapter 2 is an investigation of two novels: The Silent Minaret (2005) and I See You (2014), by the South African writer, Ishtiyaq Shukri. By situating his characters in a variety of geopolitical spaces and temporal realities, Shukri encourages the reader to discard the structuring frames of nation, race, and religion, and links the vulnerability and violence implicit in the War on Terror to a longer history of conquest, colonialism, and apartheid. In the process, Shukri illustrates the importance of understanding repressive local contexts as interwoven with global and historical power dynamics. Chapter 3 is a study of the popular American television series, Homeland (2011—), created by Alex Gansa and Howard Gordon, and focuses on the manner in which the Central Intelligence Agency’s “Overseas Contingency Operations” are portrayed by the show. I argue that Homeland initially problematises the ‘friend’/‘enemy’ binary, but subsequently collapses into a narrative in which these two polarities are construed by prevailing American attitudes towards Islam and the notion of the War on Terror as a necessity. This thesis concludes that texts that characterise the War on Terror as a global phenomenon, and situate it within a broad historical discourse, are able to subvert the singularity ascribed to the 9/11 attacks, as well as the epochal connotations of the ‘post-9/11 ’ literary genre. I argue that the novels I have chosen scrutinise the ways in which perceptions are framed by dominant forms of media, historiography, and political rhetoric, and not only offer unique insights on the repercussions of the global War on Terror but attempt to conceive of humanity in its totality, and therefore destabilise the ontological and reductive operation of the frame itself

HIV in contemporary Vietnam : an anthropology of development

HIV officially arrived in Vietnam with the reporting of the first case in December 1990. All available research pointed to the fact that Vietnam was about to become part of the AIDS pandemic. Through the complex, dynamic exchanges of discourses between development agencies, HIV prevention groups and governments, the 'threat' of HIV and AIDS was created. 1 At the same time, Vietnam was experiencing rapid and extreme social and economic changes. This thesis explores the modalities through which the threat of HIV and AIDS has been socially constructed in contemporary Vietnam. It was a time when Vietnam increased its efforts to modernise and become once again part of the global economy and thus it was especially vulnerable to particular readings of the dominant global discourses about the disease

NOTES ON EUROPE. THE DOGMATIC SLEEP. Proc

The notion of "Europe" has been questioned since the last decades of the twentieth century, especially in the territory of the so-called European Studies. Since World War II, Europe has lost its visionary project of a privileged race of the human kind, thanks to the consequences of its policy of self-destruction, already present in the first half of the last century, to the effects of decolonization and the loss of ethnocentrism. The convulsions at the level of world politics and geopolitics definitely change the course of history. What Europe is left after the great historical controversies that have crossed and continue to cross it? What critical framework is possible to outline today so as to understand the various interactions and disseminations that make Europe fundamentally a kind of financial and commercial brand? What place can there still exist in the world for a Europe that does not yield to the imperialist tradition? As Sloterdijk critically questions, is this commonplace that tries to formulate Europe as a "unity of differences" or "a set of contradictions" a empty one? What is the possibility of a heterotopic becoming for Europe? How to wake it from the dogmatic sleep as did Kant in respect to Reason? Since the modern age, in which European cartography has practically reduced the terrestrial globe and the representation of the world to Europe, until today, the old continent loses its enchantment, its mystical character, being increasingly challenged as a paradigm. If it is true that it will continue to be privileged, this fact can not prevent us from thinking about what we are as history, from establishing a dialogue with ourselves, a kind of personal archeology. Similarly, in the territory of art, Europe has been the subject of complex debates, in the domain of which some artists have been called in to participate, questioning both the political reorganization of post-Second World War, recent political decisions, or artistic mapping based in geopolitical strategies in a global context. If European art was regarded as the world’s art, its protectorate seems to have been emptied. Will those who Sloterdijk calls "the second-rate artists" be the ones who continue to overestimate heterogeneity and otherness, making efforts to maintain the myth of the European dream? Proceedings of the international conference “NOTES ON EUROPE. The dogmatic sleep” (Porto: ESAP, October 29-31, 2019)info:eu-repo/semantics/publishedVersio

Reports to the President

A compilation of annual reports for the 1981-1982 academic year, including a report from the President of the Massachusetts Institute of Technology, as well as reports from the academic and administrative units of the Institute. The reports outline the year's goals, accomplishments, honors and awards, and future plans

Ten Journeys to Cameron’s Farm

Three decades after what he called ‘a dreadful air crash, almost within sight of my windows’ Robert Menzies wrote ‘I shall never forget that terrible hour; I felt that for me the end of the world had come…’ Ten Journeys to Cameron’s Farm tells the lives of the ten men who perished in Duncan Cameron’s Canberra property on 13 August 1940: three Cabinet ministers, the Chief of the General Staff, two senior staff members, and the RAAF crew of four. The inquiries into the accident, and the aftermath for the Air Force, government, and bereaved families are examined. Controversial allegations are probed: did the pilot F/Lt Bob Hitchcock cause the crash or was the Minister for Air Jim Fairbairn at the controls? ‘Cameron Hazlehurst is a story-teller, one of the all-too rare breed who can write scholarly works which speak to a wider audience. In the most substantial, original, and authoritative account of the Canberra aircraft accident of August 1940 he provides unique insights into a critical, poignant moment in Australian history. Hazlehurst’s account is touched with irony and quirks, set within a framework of political, social, and military history, distinctions of class, education, and rank, and the machinations of parliamentary and service politics and of the ‘official mind’. The research is meticulous and wide-ranging, the analysis is always balanced, and the writing at once skilful and compelling. This is a work of an exceptional historian.’ (Ian Hancock, author of Nick Greiner: A Political Biography, John Gorton: He Did It His Way, and National and Permanent? The Federal Organisation of the Liberal Party of Australia) ‘Ten Journeys to Cameron’s Farm is a monumental work of historical research pegged on a single, lethal moment at the apex of government at an extraordinarily sensitive time in Australia’s history. The book embodies top drawer scholarship, deep sensitivity to antipodean class structures and sensibilities, and a nuanced understanding of both democratic and bureaucratic politics.’ (Christine Wallace, author of Germaine Greer Untamed Shrew and The Private Don: the man behind the legend of Don Bradman