Intrinsic noise of microRNA-regulated genes and the ceRNA hypothesis

MicroRNAs are small noncoding RNAs that regulate genes post-transciptionally by binding and degrading target eukaryotic mRNAs. We use a quantitative model to study gene regulation by inhibitory microRNAs and compare it to gene regulation by prokaryotic small non-coding RNAs (sRNAs). Our model uses a combination of analytic techniques as well as computational simulations to calculate the mean-expression and noise profiles of genes regulated by both microRNAs and sRNAs. We find that despite very different molecular machinery and modes of action (catalytic vs stoichiometric), the mean expression levels and noise profiles of microRNA-regulated genes are almost identical to genes regulated by prokaryotic sRNAs. This behavior is extremely robust and persists across a wide range of biologically relevant parameters. We extend our model to study crosstalk between multiple mRNAs that are regulated by a single microRNA and show that noise is a sensitive measure of microRNA-mediated interaction between mRNAs. We conclude by discussing possible experimental strategies for uncovering the microRNA-mRNA interactions and testing the competing endogenous RNA (ceRNA) hypothesis.Comment: 32 pages, 11 figure

Physics of epigenetic landscapes and statistical inference by cells

Biology is currently in the midst of a revolution. Great technological advances have led to unprecedented quantitative data at the whole genome level. However, new techniques are needed to deal with this deluge of high-dimensional data. Therefore, statistical physics has the potential to help develop systems biology level models that can incorporate complex data. Additionally, physicists have made great strides in understanding non-equilibrium thermodynamics. However, the consequences of these advances have yet to be fully incorporated into biology. There are three specific problems that I address in my dissertation. First, a common metaphor for describing development is a rugged "epigenetic landscape" where cell fates are represented as attracting valleys resulting from a complex regulatory network. I introduce a framework for explicitly constructing epigenetic landscapes that combines genomic data with techniques from spin-glass physics. The model reproduces known reprogramming protocols and identifies candidate transcription factors for reprogramming to novel cell fates, suggesting epigenetic landscapes are a powerful paradigm for understanding cellular identity. Second, I examine the dynamics of cellular reprogramming. By reanalyzing all available time-series data, I show that gene expression dynamics during reprogramming follow a simple one-dimensional reaction coordinate that is independent of both the time and details of experimental protocol used. I show that such a reaction coordinate emerges naturally from epigenetic landscape models of cell identity where cellular reprogramming is viewed as a "barrier-crossing" between the starting and ending cell fates. Overall, the analysis and model suggest that gene expression dynamics during reprogramming follow a canonical trajectory consistent with the idea of an "optimal path"' in gene expression space for reprogramming. Third, an important task of cells is to perform complex computations in response to external signals. Intricate networks are required to sense and process signals, and since cells are inherently non-equilibrium systems, these networks naturally consume energy. Since there is a deep connection between thermodynamics, computation, and information, a natural question is what constraints does thermodynamics place on statistical estimation and learning. I modeled a single chemical receptor and established the first fundamental relationship between the energy consumption and statistical accuracy of a receptor in a cell

STRUGGLE IN THE HIGH NORTH: USMC IN NORWAY AND THE CONTINUITY AND CHANGE IN ROLES, MISSIONS, AND DETERRENCE AMID GREAT POWER COMPETITION

While climate change continues to reduce Arctic ice coverage, Russia’s expanding Arctic territorial claims and military buildup raise security concerns for Arctic states, specifically Norway, and have renewed NATO’s interest in the region. The Marine Corps has a longstanding role in the High North of Norway, contributing to the deterrence of Soviet aggression during the Cold War. During the same period, the Marine Corps balanced its additional rapid deployment requirements by increasing interoperability with Norway through annual exercises and pre-staging equipment for a quicker response capability. Currently, the Marine Corps is undergoing a deliberate shift to a maritime force focused on the Indo-Pacific amid great power competition with China. This thesis explores the Marine Corps’ future role in collective defense against Russia via NATO and its relationship with Norway. The research considered Russian and NATO interests in the Arctic and how lessons from the Marine Corps’ historic balancing of requirements of the Cold War apply toward emerging challenges. This thesis recommends utilizing aspects of the Marine Corps’ future operating concept to strengthen Norway’s and, by extension, NATO’s ability to deter Russian aggression in the High North.Major, United States Marine CorpsApproved for public release. Distribution is unlimited

Uma pesquisa em periódicos, congressos e livros, sobre contabilidade e gestão nas áreas de turismo e hotelaria

TCC (Graduação) - Universidade Federal de Santa Catarina. Centro Socioeconômico. Curso de Ciências ContábeisNesta monografia, que tem como objetivo, servir como um guia ao leitor que queira pesquisar nesta área, buscou-se pesquisar, através de livros, congressos e revistas, sobre a área da contabilidade e gerência em empresas turísticas e hoteleiras. Durante a realização deste trabalho, foram pesquisados, os mais importantes periódicos e congressos na área da Administração e da Contabilidade, foram eles o ENANPAD, Congresso Brasileiro de Custos, o Congresso Brasileiro de Contabilidade, a Revista do CRC de vários estados, a Revista do Conselho Regional de Contabilidade, a Revista de Contabilidade e Finanças, as Revistas de Administração da USP e da FGV, Revista de administração contemporânea e a Revista de Organização e Sociedade. Depois de analisados e apresentados todos os artigos encontrados sobre turismo e hotelaria nos periódicos e congressos, chegou-se a conclusão que muito poucos artigos são publicados na área de contabilidade hoteleira, portanto, em uma segunda etapa buscou-se analisar artigos do Portal Capes

Trichromatic Open Digraphs for Understanding Qubits

We introduce a trichromatic graphical calculus for quantum computing. The generators represent three complementary observables that are treated on equal footing, hence reflecting the symmetries of the Bloch sphere. We derive the Euler angle decomposition of the Hadamard gate within it as well as the so-called supplementary relationships, which are valid equations for qubits that were not derivable within Z/X-calculus of Coecke and Duncan. More specifically, we have: dichromatic Z/X-calculus + Euler angle decomposition of the Hadamard gate = trichromatic calculus.Comment: In Proceedings QPL 2011, arXiv:1210.029

Employee Work Ethic in Nine Nonindustrialized Contexts: Some Surprising Non-POSH Findings

Gross, Carr, Reichman, Abdul-Nasiru, and Oestereich's (2017) article argues that industrial and organizational (I-O) psychology has a limited perspective that rarely goes beyond the specific professional populations in formal economies of high-income countriesa perspective they refer to as a POSH perspective. This valuable criticism should also eschew the notion that workers in nonindustrialized countries are necessarily different