Distributed Lagrangian Methods for Network Resource Allocation

Motivated by a variety of applications in control engineering and information sciences, we study network resource allocation problems where the goal is to optimally allocate a fixed amount of resource over a network of nodes. In these problems, due to the large scale of the network and complicated inter-connections between nodes, any solution must be implemented in parallel and based only on local data resulting in a need for distributed algorithms. In this paper, we propose a novel distributed Lagrangian method, which requires only local computation and communication. Our focus is to understand the performance of this algorithm on the underlying network topology. Specifically, we obtain an upper bound on the rate of convergence of the algorithm as a function of the size and the topology of the underlying network. The effectiveness and applicability of the proposed method is demonstrated by its use in solving the important economic dispatch problem in power systems, specifically on the benchmark IEEE-14 and IEEE-118 bus systems

On the convergence rate of distributed gradient methods for finite-sum optimization under communication delays

Motivated by applications in machine learning and statistics, we study distributed optimization problems over a network of processors, where the goal is to optimize a global objective composed of a sum of local functions. In these problems, due to the large scale of the data sets, the data and computation must be distributed over processors resulting in the need for distributed algorithms. In this paper, we consider a popular distributed gradient-based consensus algorithm, which only requires local computation and communication. An important problem in this area is to analyze the convergence rate of such algorithms in the presence of communication delays that are inevitable in distributed systems. We prove the convergence of the gradient-based consensus algorithm in the presence of uniform, but possibly arbitrarily large, communication delays between the processors. Moreover, we obtain an upper bound on the rate of convergence of the algorithm as a function of the network size, topology, and the inter-processor communication delays

The transcriptional repressor protein growth factor independence-1B in T lymphopoiesis.

T lymphopoiesis has been an intense focus of immunological research since the discovery of the major histocompatibility complex (MHC) and T cell mediated transplant rejection. Additionally, researchers have long appreciated the role of T cells, and their development, in autoimmune disorders. Interest in this field has increased upon the realization that many leukemic oncoproteins are the very factors that control normal T cell development. Thus, the transcriptional networks that drive the function and development of T lymphocytes are closely linked with disease states.Growth Factor Independence 1 (GFI1) and GFI1B are two very similar transcriptional repressor oncoproteins that are encoded by two different genes. Though nearly identical in their DNA binding and repressor domains, GFI1 and GFI1B are differentially expressed in normal tissues and in tumors of lymphoid lineage. GFI1 is frequently activated in mouse T cell leukemias, whereas GFI1B has not been found in T cell tumors. The work described in this dissertation provides insight into this phenomenon by delineating functional differences for GFI1 and GFI1B in T cells.The first set of experiments compares the phenotypes engendered by transgenic expression of either GFI1 or GFI1B in developing and mature T lymphocytes. These analyses revealed that GFI1 enhances the response to T cell activation, whereas GFI1B decreases this response. Furthermore, transgenic GFI1B causes defects in thymocyte development, some of which result from a lack of survival signals. These defects can be corrected by transgenic expression of either BCL2, an inhibitor of apoptosis, or GFI1, suggesting that GFI1 and GFI1B play opposing roles in T cell survival.At least part of the effect of transgenic GFI1B results from GFI1B-mediated repression of Gfi1 transcription. We show that the transcription of Gfi1 is repressed in T cells by both GFI1 and GFI1B and that this is the result of direct binding to evolutionarily conserved GFI1/GFI1B recognition sequences in the Gfi1 promoter. Furthermore, we provide evidence that endogenous GFI1 regulates its own promoter in T cells, but not in a myeloid lineage cell line.Finally, a more detailed analysis of the effect of GFI1B in T lymphopoiesis confirms a role for GFI1B in the survival and differentiation of thymocytes. This analysis revealed that transgenic expression of GFI1B results in altered expression of several members of T cell receptor (TCR) signaling pathways that are largely responsible for the survival and differentiation of thymocytes. The activity of the downstream effectors of these pathways appears to be decreased, providing mechanistic insight in to the function of GFI1B in T cells.Our work is the first to describe a role for GFIB in T cells. We demonstrate that GFI1B negatively regulates the cellular response to activation through the TCR complex and provide preliminary evidence of a mechanism by which GFI1B mediates these effects. Furthermore, we delineate functional differences for GFI1 and GFI1B in T cells, providing insight into the differential expression of these two transcription factors

Interpersonal emotion regulation: a review of social and developmental components

A staple theme in clinical psychology, emotion regulation, or the ability to manage one's emotions, is directly linked with personal wellbeing and the ability to effectively navigate the social world. Until recently, this concept has been limited to a focus on intrapersonal processes, such as suppression. Less emphasis has been placed on developmental, social, and cultural aspects of emotion regulation. We argue here that as social beings, our engagement in emotion regulation may often occur interpersonally, with trusted others helping us to regulate our emotions. This review will highlight recent research on interpersonal emotion regulation processes.Dr Hofmann receives financial support from the Alexander von Humboldt Foundation (as part of the Humboldt Prize), NIH/NCCIH (R01AT007257), NIH/NIMH (R01MH099021, U01MH108168), and the James S. McDonnell Foundation 21st Century Science Initiative in Understanding Human Cognition - Special Initiative. He receives compensation for his work as an advisor from the Palo Alto Health Sciences and for his work as a Subject Matter Expert from John Wiley & Sons, Inc. and SilverCloud Health, Inc. He also receives royalties and payments for his editorial work from various publishers. (Alexander von Humboldt Foundation; R01AT007257 - NIH/NCCIH; R01MH099021 - NIH/NIMH; U01MH108168 - NIH/NIMH; James S. McDonnell Foundation 21st Century Science Initiative in Understanding Human Cognition - Special Initiative)Accepted manuscrip

Re-Orienting Planning Practice

This commentary reflects on the articles in the thematic issue on queering urban planning and municipal governance and the ways that they suggest that planning practice must be re-oriented to be more inclusive and incorporate more insurgent perspectives. Planning practice is susceptible to capture by neo-liberal corporate interests that marginalize vulnerable queer populations. More insurgent planning approaches are needed to resist the corporate take-over of queer spaces by empowering the voices of LGBTQ+ people

Low-Energy Polymeric Phases of Alanates

Low-energy structures of alanates are currently known to be described by patterns of isolated, nearly ideal tetrahedral [AlH$_4$] anions and metal cations. We discover that the novel polymeric motif recently proposed for LiAlH$_4$ plays a dominant role in a series of alanates, including LiAlH$_4$, NaAlH$_4$, KAlH$_4$, Mg(AlH$_4$)$_2$, Ca(AlH$_4$)$_2$ and Sr(AlH$_4$)$_2$. In particular, most of the low-energy structures discovered for the whole series are characterized by networks of corner-sharing [AlH$_6$] octahedra, forming wires and/or planes throughout the materials. Finally, for Mg(AlH$_4$)$_2$ and Sr(AlH$_4$)$_2$, we identify two polymeric phases to be lowest in energy at low temperatures.Comment: 9 pages, 8 figures, 2 tables, including supplemental materia

First-principles predicted low-energy structures of NaSc(BH4)4

According to previous interpretations of experimental data, sodium-scandium double-cation borohydride NaSc(BH$_4$)$_4$ crystallizes in the crystallographic space group $Cmcm$ where each sodium (scandium) atom is surrounded by six scandium (sodium) atoms. A careful investigation of this phase based on \textit{ab initio} calculations indicates that the structure is dynamically unstable and gives rise to an energetically and dynamically more favorable phase with $C222_1$ symmetry and nearly identical x-ray diffraction pattern. By additionally performing extensive structural searches with the minima-hopping method we discover a class of new low-energy structures exhibiting a novel structural motif in which each sodium (scandium) atom is surrounded by four scandium (sodium) atoms arranged at the corners of either a rectangle with nearly equal sides or a tetrahedron. These new phases are all predicted to be insulators with band gaps of $7.9-8.2$ eV. Finally, we estimate the influence of these structures on the hydrogen-storage performance of NaSc(BH$_4$)$_4$.Comment: Version publishe

Metagenomic deep sequencing of aqueous fluid detects intraocular lymphomas.

IntroductionCurrently, the detection of pathogens or mutations associated with intraocular lymphomas heavily relies on prespecified, directed PCRs. With metagenomic deep sequencing (MDS), an unbiased high-throughput sequencing approach, all pathogens as well as all mutations present in the host's genome can be detected in the same small amount of ocular fluid.MethodsIn this cross-sectional case series, aqueous fluid samples from two patients were submitted to MDS to identify pathogens as well as common and rare cancer mutations.ResultsMDS of aqueous fluid from the first patient with vitreal lymphoma revealed the presence of both Epstein-Barr virus (HHV-4/EBV) and human herpes virus 8 (HHV-8) RNA. Aqueous fluid from the second patient with intraocular B-cell lymphoma demonstrated a less common mutation in the MYD88 gene associated with B-cell lymphoma.ConclusionMDS detects pathogens that, in some instances, may drive the development of intraocular lymphomas. Moreover, MDS is able to identify both common and rare mutations associated with lymphomas

Heart simulator: A periodic pump to simulate the cardiac motion in an aortic test-rig

A periodic pump that simulates blood ejection from human heart to aorta is the core element for building an aortic robotics test-rig. This paper is to describe the design of such a prototype human heart simulator and its performance under different working status, such as simulating the physiological states of a healthy adult and/or a child in sleep, relax and physical exercise. By balancing the cost and performance, this prototype has these specifications: (1) Using ordinary plumbing components and water to simulate the cardiac motion and blood flow. (2) Simulating the volume change of human heart chamber by controlling movement of a mechanical piston. (3) Performing a friendly user interface and delicate control via a MCU system with high reliability. (4) Simulated physiological output parameters such as volume per stroke, heart beat rate and waveform can be easily adjusted and monitored in real-time