Using Sequences of rbcL to Study Phylogeny and Biogeography of Nothofagus Species

1993 ◽  
Vol 6 (5) ◽  
pp. 441 ◽  
Author(s):  
PG Martin ◽  
JM Dowd
Keyword(s):  
Phylogenetic Trees ◽  
Nucleotide Change ◽  
Rate Of Evolution ◽  
Early Stages ◽  
The Common ◽  
Common Ancestors

Sequences of rbcL for 23 species of Nothofagus and three of Fagus have been determined and analysed to form phylogenetic trees. The two genera are well separated. The species of Nothofagus separate into lineages which correspond exactly with the subgenera recently defined on morphological grounds. The rate of evolution of the four subgenera is shown to be statistically the same and, using a reference date from palaeobotany, is found to be one nucleotide change in 6 Ma. This rate is used to derive the ages of the common ancestors of species in subgenera and it is tentatively concluded that intercontinental dispersal was possible in the early stages of the evolution of the genus.

Getting College-Ready during State Transition toward the Common Core State Standards

2018 ◽  
Vol 120 (6) ◽  
pp. 1-36
Author(s):  
Zeyu Xu ◽  
Kennan Cepa
Keyword(s):  
High School ◽  
Student Learning ◽  
College Readiness ◽  
Common Core ◽  
Common Core State Standards ◽  
State Standards ◽  
Core State ◽  
Act Scores ◽  
Early Stages ◽  
The Common

Background As of 2016, 42 states and the District of Columbia have adopted the Common Core State Standards (CCSS). Tens of millions of students across the country completed high school before their schools were able to fully implement the CCSS. As with previous standards-based reforms, the transition to the CCSS-aligned state education standards has been accompanied by curriculum framework revisions, student assessment redesigns, and school accountability and educator evaluation system overhauls. Purpose Even if the new standards may improve student learning once they are fully implemented, the multitude of changes at the early implementation stage of the reform might disrupt student learning in the short run as teachers, schools, and communities acclimate to the new expectations and demands. The goal of this study is not to evaluate the merits and deficiencies of the CCSS per se, but rather to investigate whether college readiness improved among high school students affected by the early stages of the CCSS implementation, and whether students from different backgrounds and types of high schools were affected differently. Research Design We focus on three cohorts of 8theighth-grade students in Kentucky and follow them until the end of the 11th -grade, when they took the state mandatory ACT tests. The three successive cohorts—enrolled in the 8theighth -grade between 2008 and 2010—each experienced different levels of exposure to CCSS transition. Using ACT scores as proxy measures of college readiness, we estimate cohort fixed-effects models to investigate the transitional impact of standards reform on student performance on the ACT. To gauge the extent to which the implementation of CCSS is directly responsible for any estimated cross-cohort differences in student ACT performance, we conduct additional difference-in-differences analyses and a falsification test. Data Our data include the population of 3 three cohorts of 8theighth -graders enrolled in Kentucky public schools between 2008 and 2010. The total analytic sample size is 100,212. The data include student test scores, student background characteristics, and school characteristics. Findings In the case of the CCSS transition in Kentucky, our findings suggest that students continued to improve their college -readiness, as measured by ACT scores, during the early stages of CCSS implementation. Furthermore, evidence suggests that the positive gains students made during this period accrue to students in both high- and low-poverty schools. However, it is not conclusive that the progress made in student college -readiness is necessarily attributable to the new content standards. Conclusions As we seek to improve the education of our children through reforms and innovations, policymakers should be mindful about the potential risks of excessive changes. Transition issues during the early stages of major educational changes sometimes lead to short-term effects that are not necessarily indicative of the longer-term effects of a program or intervention. Nevertheless, standards-based reforms are fairly frequent, and each takes multiple years to be fully implemented, affecting millions of students. Therefore, we encourage researchers and policymakers to pay more attention to the importance of transitional impact of educational reforms.

Risks of Using Statistical Analysis Tools in Project Management Environments

2020 ◽  
Vol 7 (2) ◽  
pp. 1-19
Author(s):  
Brian J. Galli
Keyword(s):  
Risk Management ◽  
Project Management ◽  
Statistical Analysis ◽  
Common Type ◽  
Systematic Search ◽  
Statistical Tools ◽  
Early Stages ◽  
Analysis Tools ◽  
The Common ◽  
The Relationship

The purpose of this study is to examine the risks of using statistical tools in a project basis. A systematic search of certain academic databases has been conducted for this study. Statistical tools could be used in a project, and they should be properly planned and designed. Statistical tools include major activities, such as collecting and analyzing data, providing meaningful interpretation, and reporting findings. When dealing with statistical tools, there are several risks that may exist and impact the project either positively or negatively. This study covers a brief outline of the risk management, statistical tools, and the relationship between the two concepts. Finally, a discussion of the common type of risks that are initiated by using statistical analysis tools are provided, which could be planned, identified, and analyzed in the early stages of the project.

scholarly journals Visual Comparison of Phylogenetic Trees Through iPhyloC, a New Interactive Web-based Framework

2021 ◽  
Author(s):  
Muhsen Hammoud ◽  
Charles Morphy Santos ◽  
Joao Paulo Gois
Keyword(s):  
Phylogenetic Trees ◽  
Binary Trees ◽  
Automatic Identification ◽  
Structural Comparison ◽  
Web Based ◽  
Visual Comparison ◽  
Large Trees ◽  
Cross Platform ◽  
The Common ◽  
Intuitive Design

Current side-by-side phylogenetic trees comparison frameworks face two issues: (1) accepting binary trees as input, and (2) assuming input trees having identical or highly overlapping taxa. We present a task abstraction of the problem of side-by-side comparison of two phylogenetic trees and propose a set-based measure for detailed structural comparison between two phylogenetic trees, which can be non-binary and not highly overlapping. iPhyloC is an interactive web-based framework including automatic identification of the common taxa in both trees, comparing input trees in several modes, intuitive design, high usability, scalability to large trees, and cross-platform support. iPhyloC was tested in hypothetical and real biological examples.

Molecular phylogeny of Fordini (Hemiptera: Aphididae: Pemphiginae) inferred from nuclear gene EF-1 α and mitochondrial gene COI

2007 ◽  
Vol 97 (4) ◽  
pp. 379-386 ◽  
Author(s):  
H.C. Zhang ◽  
G.X. Qiao
Keyword(s):  
Phylogenetic Trees ◽  
Host Plants ◽  
Mitochondrial Gene ◽  
Nuclear Gene ◽  
Morphological Characters ◽  
Primary Host ◽  
Gene Coi ◽  
The Common ◽  
Different Parts ◽  
Selection Of

AbstractThe tribe Fordini is a fascinating group because of its complicated life history, primary host specificity and gall-forming characteristic. Different species produce galls with different morphology on different parts of the host plants. The EF-1α-based, COI-based and combined sequences-based phylogenetic trees with three algorithms MP, ML and Bayes all strongly suggest that Fordini is a monophyletic group with two clades corresponding to two subtribes, Fordina and Melaphidina, each also monophyletic. Some important morphological characters and primary host plants of aphids were mapped onto the phylogenetic tree to analyse the division of subtribes and to uncover at which level the aphids correspond to their primary hosts, Pistacia and Rhus. Results suggest that the division of subtribes in Fordini is closely related to host selection of aphids. The evolution of gall morphology and the probable driving force behind it in this tribe were also discussed. The Fordini aphids seem to have evolved towards a better ability to manipulate their host plant, induce strong sinks and gain high reproductive success. Galls in this tribe evolved mainly along two directions to attain this goal: (i) by enlarging the gall from small bag to spherical, even big cauliflower-like, and changing the galls' location or forming two galls in their life cycle (Fordina); (ii) by moving the gall position from midrib, petiole of the leaflet, and eventually to the common petiole of the compound leaf (Melaphidina).

scholarly journals No ‘small genome attraction’ artifact: A response to Harish et al. ‘Did viruses evolve as a distinct supergroup from common ancestors of cells?’

2016 ◽  
Author(s):  
Arshan Nasir ◽  
Kyung Mo Kim ◽  
Gustavo Caetano-Anollés
Keyword(s):  
Phylogenetic Trees ◽  
Recent Literature ◽  
Viral Evolution ◽  
Tree Of Life ◽  
Tree Topology ◽  
Tree Reconstruction ◽  
Small Genome ◽  
Cellular Origin ◽  
Common Ancestors

In a recent eLetter and associated preprint, Harish, Abroi, Gough and Kurland criticized our structural phylogenomic methods, which support the early cellular origin of viruses. Their claims include the argument that the rooting of our trees is artifactual and distorted by small genome (proteome) size. Here we uncover their aprioristic reasoning, which mingles with misunderstandings and misinterpretations of cladistic methodology. To demonstrate, we labeled the phylogenetic positions of the smallest proteomes in our phylogenetic trees and confirm that the smallest genomes were neither attracted towards the root nor caused any distortions in the four-supergroup tree of life. Their results therefore stem from confusing outgroups with ancestors and handpicking problematic taxa to distort tree reconstruction. In doing so, they ignored the details of our rooting method, taxa sampling rationale, the plethora of evidence given in our study supporting the ancient origin of the viral supergroup and also recent literature on viral evolution. Indeed, our tree of life uncovered many viral monophyletic groups consistent with ICTV classifications and showed remarkable evolutionary tracings of virion morphotypes onto a revealing tree topology.

scholarly journals The Political Economy of Europe since 1945 A Kaleckian Perspective

2019 ◽  
pp. 1-20 ◽  
Author(s):  
Joseph Halevi
Keyword(s):  
United States ◽  
Political Economy ◽  
European Integration ◽  
The United States ◽  
Common Market ◽  
West Germany ◽  
Great Power ◽  
The Political ◽  
Early Stages ◽  
The Common

This paper analyzes the early stages of the formation of the Common Market. The period covered runs from the end of WW2 to 1959, which is the year in which the European Payments Union ceased to operate. The essay begins by highlighting the differences between the prewar political economy of Europe and the new dimensions and institutions brought in by the United States after 1945. It focuses on the marginalization of Britain and on the relaunching of French great power ambitions and how the latter determined, in a very problematical way, the European complexion of France. Because of France’s imperial aspirations, France, not West Germany, emerged as the politically crisis prone country of Europe acting as a factor of instability thereby jeopardizing the process of European integration, Among the large European nations, Germany and Italy appear, for opposite economic reasons, as the countries most focused on furthering integration. Germany expressed the strongest form of neomercantilism while Italy the weakest.

Common generic block: Mass customization for shipbuilding

2003 ◽  
Vol 217 (2) ◽  
pp. 79-94 ◽  
Author(s):  
R L Storch ◽  
S Sukapanpotharam
Keyword(s):  
Mass Customization ◽  
Threshold Value ◽  
Stopping Criterion ◽  
Clustering Techniques ◽  
Customer Needs ◽  
Early Stages ◽  
World Class ◽  
The Common ◽  
Block Complexity

Productive shipbuilders provide customized or made-to-order products to customers. To date, most of these ‘world class’ companies have succeeded by developing a series of repeatable type blocks which may be chosen and combined to form products that respond to customer needs. Type blocks have been developed as a result of long experience in customizing ships to specific needs while maintaining a repeatable build strategy. These are therefore empirically based. This paper reports on the early stages of work to develop a theory and methodology for developing type blocks for shipyards that do not currently have them in place and/or lack the historical base from which to extract common blocks. The concept of the common generic block (CGB) builds these using the principles of mass customization, a block complexity matrix, grouping using clustering techniques based on production attributes and applying a threshold value as a stopping criterion for the clustering.

Haplosporosomes, sporoplasmosomes and their putative taxonomic relationships in rhizarians and myxozoans

Parasitology ◽  
2020 ◽  
Vol 147 (14) ◽  
pp. 1614-1628
Author(s):  
P.M. Hine ◽  
D.J. Morris ◽  
C. Azevedo ◽  
S.W. Feist ◽  
G. Casal
Keyword(s):  
Plasma Membrane ◽  
Current Knowledge ◽  
Host Cells ◽  
Common Method ◽  
Taxonomic Relationships ◽  
Internal Membrane ◽  
The Common ◽  
Golgi Network ◽  
Common Ancestors

AbstractThis paper reviews current knowledge of the structure, genesis, cytochemistry and putative functions of the haplosporosomes of haplosporidians (Urosporidium, Haplosporidium, Bonamia, Minchinia) and paramyxids (Paramyxa, Paramyxoides, Marteilia, Marteilioides, Paramarteilia), and the sporoplasmosomes of myxozoans (Myxozoa – Malacosporea, Myxosporea). In all 3 groups, these bodies occur in plasmodial trophic stages, disappear at the onset of sporogony, and reappear in the spore. Some haplosporidian haplosporosomes lack the internal membrane regarded as characteristic of these bodies and that phylum. Haplosporidian haplosporogenesis is through the Golgi (spherulosome in the spore), either to form haplosporosomes at the trans-Golgi network, or for the Golgi to produce formative bodies from which membranous vesicles bud, thus acquiring the external membrane. The former method also forms sporoplasmosomes in malacosporeans, while the latter is the common method of haplosporogenesis in paramyxids. Sporoplasmogenesis in myxosporeans is largely unknown. The haplosporosomes of Haplosporidium nelsoni and sporoplasmosomes of malacosporeans are similar in arraying themselves beneath the plasmodial plasma membrane with their internal membranes pointing to the exterior, possibly to secrete their contents to lyse host cells or repel haemocytes. It is concluded that these bodies are probably multifunctional within and between groups, their internal membranes separating different functional compartments, and their origin may be from common ancestors in the Neoproterozoic.

EARLY STAGES IN THE LIFE HISTORY OF THE COMMON MARINE SHRIMP, PENAEUS SETIFERUS (LINNAEUS)

1949 ◽  
Vol 96 (2) ◽  
pp. 168-172 ◽  
Author(s):  
WILLIAM W. ANDERSON ◽  
JOSEPH E. KING ◽  
MILTON J. LINDNER
Keyword(s):  
Life History ◽  
Early Stages ◽  
Penaeus Setiferus ◽  
Marine Shrimp ◽  
History Of ◽  
The Common

Plecopteracoluthus downesi gen. et sp. nov. (Diptera: Chironomidae), a Species Whose Larvae Live Phoretically on Larvae of Plecoptera

1965 ◽  
Vol 97 (12) ◽  
pp. 1323-1344 ◽  
Author(s):  
A. W. Steffan
Keyword(s):  
New Genus ◽  
Adult Stage ◽  
Immature Stages ◽  
New Genus And Species ◽  
Life Pattern ◽  
The Common ◽  
Laboratory Life ◽  
Common Ancestors

AbstractIn a creek northwest of the Gatineau Hills (Quebec) larvae of Chironomidae (Diptera) were found living in phoretic association with the immature stages of Perlidae (Plecoptera). The larvae were reared to the adult stage in the laboratory. Life pattern and morphological comparisons are made with other phoretic and parasitic forms of Orthocladiinae and with certain other genera, and it is concluded that the form represents a new genus and species of Orthocladiini, and has probably originated from the common ancestors of the genera Rheocricotopus, Paracricotopus and Microcricotopus. Detailed descriptions are given of the imago, pupa and larva of this insect.

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