1,644 research outputs found
The early expansion and evolutionary dynamics of POU class genes.
The POU genes represent a diverse class of animal-specific transcription factors that play important roles in neurogenesis, pluripotency, and cell-type specification. Although previous attempts have been made to reconstruct the evolution of the POU class, these studies have been limited by a small number of representative taxa, and a lack of sequences from basally branching organisms. In this study, we performed comparative analyses on available genomes and sequences recovered through "gene fishing" to better resolve the topology of the POU gene tree. We then used ancestral state reconstruction to map the most likely changes in amino acid evolution for the conserved domains. Our work suggests that four of the six POU families evolved before the last common ancestor of living animals-doubling previous estimates-and were followed by extensive clade-specific gene loss. Amino acid changes are distributed unequally across the gene tree, consistent with a neofunctionalization model of protein evolution. We consider our results in the context of early animal evolution, and the role of POU5 genes in maintaining stem cell pluripotency
State Space Methods in Stata
We illustrate how to estimate parameters of linear state-space models using the Stata program sspace. We provide examples of how to use sspace to estimate the parameters of unobserved-component models, vector autoregressive moving-average models, and dynamic-factor models. We also show how to compute one-step, filtered, and smoothed estimates of the series and the states; dynamic forecasts and their confidence intervals; and residuals.
Integrated Hyperspectral and Geochemical Analysis of the Upper Mississippian Meramec STACK Play and Outcrop Equivalents, Anadarko Basin and Ozark Uplift, Oklahoma
The principle goal of this project was to investigate compositional, textural, and sedimentological variability in the Oklahoma STACK Play’s Meramec Formation and time equivalent outcrops of the Pryor Creek Formation in northeastern Oklahoma and to assess the potential of a partial-SWIR (Short Wave Infrared, 900-1700 nm) hyperspectral imaging sensor for drill core and sUAS-based (small Unmanned Aircraft Systems) outcrop characterization.
The STACK Play is a colloquial term that refers to stacked unconventional petroleum reservoirs that are primarily located in Canadian, Kingfisher, Blaine, and Dewey Counties, central Oklahoma. Discovery of, and commercial production from, the play was initiated in 2011 by Newfield Exploration Co. and today comprises a significant share of unconventional petroleum production in Oklahoma. The most prolific reservoir within the STACK Play is the Meramec Formation which is approximately Meramecian in age.
Chapter 2 focuses on two drill cores from the producing Meramec Formation in Dewey and Canadian Counties of central Oklahoma. Conventional core analysis techniques, including analysis of core sedimentology, mineralogy, and geochemistry, are integrated with lab-based partial-SWIR hyperspectral analysis of both cores. The Meramec Formation comprises proximal and distal ramp deposits that include argillaceous quartz siltstones, calcareous quartz siltstones and sandstones, and lesser grainstones. Analysis of partial-SWIR hyperspectral imaging data establishes a relationship between reflectance and primary mineralogy in both cores, which was ultimately used in conjunction with other conventional core data to distinguish multiple orders of stratigraphic cyclicity in the Meramec Formation, including cyclicity that is below the resolution of typical core logging and sampling procedures.
Chapter 3 details the study of outcrops located in Pryor Quarry (Mayes County, northeast Oklahoma), which are approximately age equivalent to the Meramec Formation. The potential of sUAS-based partial-SWIR hyperspectral imaging for outcrop analysis is evaluated using lab-based full-SWIR point spectral analysis of samples taken from a vertical outcrop transect in the quarry. Outcrops of the Meramecian Pryor Creek Formation are comprised of wackestones, mudstones, quartz siltstones and to a lesser extent
Tracing The Thread: The Image Of The Labyrinth In Selected Novels By Wilkie Collins, Charles Dickens And Joseph Sheridan Le Fanu
This thesis will explore the image of the labyrinth and its use as a metaphor for the theme of ritual initiation in selected novels by Wilkie Collins, Charles Dickens, and Joseph Sheridan Le Fanu. In terms of its mythic interpretation, an aspect which as yet has not been examined at length by critics of Victorian fiction, the labyrinth or maze has significance beyond its Gothic and urban associations. Chapter One looks at the use of the image in the settings of several novels, the London of Oliver Twist, The Old Curiosity Shop, Barnaby Rudge, and Bleak House, and the labyrinthine houses and lunatic asylums of Collins and Le Fanu. Chapter Two considers some variations of the image and its evolution as an emblem of moral dilemma and psychological entrapment. It also examines the figure of the false guide or ironic Ariadne in the characters of Seth Pecksniff of Martin Chuzzlewit and Mr. Vholes of Bleak House. All three writers use the image of the labyrinth to describe a condition of alienation from the rest of the world. In so doing, they pave the way for later writers in the attempt to convey psychological states in imaginative terms. Through the characters of Ezra Jennings in The Moonstone and Dillon in The House by the Churchyard, Collins and Le Fanu experimented with the use of the psychological detective who solves problems by attempting to probe the workings of the mind. Similarly concerned with psychological issues, Le Fanu believes that successful negotiation of the maze is achieved only with a recognition of the power of God. The final chapter studies the maze-like form of Victorian mystery novels and investigates how this structure informs the plots of The Moonstone, The Woman in White, Armadale, and The House by the Churchyard. In these works, the form mirrors the content and the mysteries in the narratives find their counterparts in the labyrinthine technique of the novels
A comparison of interdisciplinary teaming and traditional departmental organization at the seventh grade
The principle of complementarity: the admissibility of cases before the international criminal court
Regarded as the most important international institution established since the United Nations, the International Criminal Court (ICQ was created to help end impunity. With its jurisdiction based on the principle of complementarity, it will only act when States are found unwilling or unable to investigate or prosecute perpetrators of serious international crimes. The provision that reflects the complementarity principle, article 17, stipulates the grounds for establishing whether a situation or a case is admissible before the Court. The said article defines the unwillingness and inability criteria, but had not provided any directive concerning instances where a State had remained inactive in relation to a crime that is under the jurisdiction of the ICC. Nevertheless, the Pre-Trial Chamber of the ICC held that a case in which a State had remained inactive is admissible. Satisfying the prerequisites of the unwillingness criteria, laid under article 17, is a difficult task which the Prosecutor must bear. It requires examining the genuineness or the bona fide, or the lack thereof, of States in initiating proceedings. Inability, the other criteria of admissibility, appears to have provided clear conditions as when it can be said that a State is unable to carry out a genuine investigation or prosecution. Whilst helpful, inability’s strict guidelines may restrain the admissibility of cases. Apart from the decision made by the Pre-Trial Chamber relating to cases of inaction, there is no admissibility determination applying article 17 which the Court had made. There are, nevertheless, significant questions that can be raised, and which relate to how article 17 might be construed and applied in practice. The essence of this study is to explore those questions and speculate possible answers
Teachers’ Approaches to Inquiry-focused Mathematics Teaching During the COVID-19 Pandemic in Hybrid and Online Settings
There is some question about the effectiveness of online or blended approaches to formal education at the elementary level (Anthony, 2019). While the COVID-19 pandemic has posed an immense challenge to elementary school teachers, the context has provided a rich setting to unearth what these best practices might be. To understand the convergence of the online setting and inquiry teaching in mathematics, we have undertaken a study to understand how elementary school teachers have sought to teach online using inquiry-focused approaches
State Space Methods in Stata
We illustrate how to estimate parameters of linear state-space models using the Stata program sspace. We provide examples of how to use sspace to estimate the parameters of unobserved-component models, vector autoregressive moving-average models, and dynamic-factor models. We also show how to compute one-step, filtered, and smoothed estimates of the series and the states; dynamic forecasts and their confidence intervals; and residuals
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