2,482 research outputs found
Distinguished minimal topological lassos
The ease with which genomic data can now be generated using Next Generation Sequencing technologies combined with a wealth of legacy data holds great promise for exciting new insights into the evolutionary relationships between and within the kingdoms of life. At the sub-species level (e.g. varieties or strains) certain edge weighted rooted trees with leaf set the set of organisms under consideration are often used to represent them. Called Dendrograms, it is well-known that they can be uniquely reconstructed from distances provided all distances on are known. More often than not, real biological datasets do not satisfy this assumption implying that the sought after dendrogram need not be uniquely determined anymore by the available distances with regards to topology, edge-weighting, or both. To better understand the structural properties a set \cL\subseteq {X\choose 2} has to satisfy to overcome this problem, various types of lassos have been introduced. Here, we focus on the question of when a lasso uniquely determines the topology of a dendrogram, that is, it is a topological lasso for it's underlying tree. We show that any set-inclusion minimal topological lasso for such a tree can be transformed into a structurally nice minimal topological lasso for . Calling such a lasso a distinguished minimal topological lasso for we characterize them in terms of the novel concept of a cluster marker map for . In addition, we present novel results concerning the heritability of such lassos in the context of the subtree and supertree problems
Theses on Ecumenical Truth and Heresy
Out of love and zeal for both truth and unity, the following theses are presented to my beloved colleagues in the Southern California District of The Lutheran Church-Missouri Synod as a constructive contribution to the current debate on altar and pulpit fellowship. They do not represent an official policy, but are only a personal, unofficial opinion offered for exploratory discussion. They reflect the hernial stance of one who lives in the tension of obedience to Jesus Christ while simultaneously remaining a responsible member of a changing synod and a changing world
Reconstructing (super)trees from data sets with missing distances: Not all is lost
The wealth of phylogenetic information accumulated over many decades of biological research, coupled with recent technological advances in molecular sequence generation, present significant opportunities for researchers to investigate relationships across and within the kingdoms of life. However, to make best use of this data wealth, several problems must first be overcome. One key problem is finding effective strategies to deal with missing data. Here, we introduce Lasso, a novel heuristic approach for reconstructing rooted phylogenetic trees from distance matrices with missing values, for datasets where a molecular clock may be assumed. Contrary to other phylogenetic methods on partial datasets, Lasso possesses desirable properties such as its reconstructed trees being both unique and edge-weighted. These properties are achieved by Lasso restricting its leaf set to a large subset of all possible taxa, which in many practical situations is the entire taxa set. Furthermore, the Lasso approach is distance-based, rendering it very fast to run and suitable for datasets of all sizes, including large datasets such as those generated by modern Next Generation Sequencing technologies. To better understand the performance of Lasso, we assessed it by means of artificial and real biological datasets, showing its effectiveness in the presence of missing data. Furthermore, by formulating the supermatrix problem as a particular case of the missing data problem, we assessed Lasso's ability to reconstruct supertrees. We demonstrate that, although not specifically designed for such a purpose, Lasso performs better than or comparably with five leading supertree algorithms on a challenging biological data set. Finally, we make freely available a software implementation of Lasso so that researchers may, for the first time, perform both rooted tree and supertree reconstruction with branch lengths on their own partial datasets
Hospitalization, Arrest, or Discharge: Important Legal and Clinical Issues in the Emergency Evaluation of Persons Believed Dangerous to Others
Making the War Powers Resolution Work: The View from the Trench (A Response to Professor Glennon)
THE NATURE OF DSS LITERATURE PRESENTED IN MAJOR IS CONFERENCE PROCEEDINGS (1980-1985)
This paper reports and analyzes the nature, content, and trends exhibited by DSS papers presented at the four major annual or biennial IS/DSS conferences during 1980-1985. (Three of the conferences held their first meeting during this period.) It then compares the findings from this analysis with those obtained with a different database, namely all DSS articles published in 22 professional journals during this same period. Inferences are drawn concerning (1) the perceived roles and benefits of conferences versus those of journals and (2) the apparent state and direction of the DSS field
An Academic Medical Center's Expansion to the European Union: A Case Study of UPMC's Joint Projects in Italy and Ireland
This case study examines the expansion of the University of Pittsburgh Medical Center (UPMC) to Italy and Ireland in the European Union. The authors use international business theory to help understand why US Academic Medical Centers (AMCs) are beginning to go abroad and, through semistructured interviews with UPMC officials, they examine the market entry issues UPMC faced when expanding to Italy and Ireland. The authors also explain why UPMC’s first successful foreign ventures took place in the European Union. They conclude with comments on several of the strategic issues that AMCs should address if they wish to successfully expand overseas
An Academic Medical Center's Expansion to the European Union: A Case Study of UPMC's Joint Projects in Italy and Ireland. Pittsburgh Papers on the European Union Vol. 3, June 2014
This case study examines the expansion of the University of Pittsburgh Medical Center (UPMC) to Italy and Ireland in the European Union. The authors use international business theory to help understand why US Academic Medical Centers (AMCs) are beginning to go abroad and, through semistructured interviews with UPMC officials, they examine the market entry issues UPMC faced when expanding to Italy and Ireland. The authors also explain why UPMC’s first successful foreign ventures took place in the European Union. They conclude with comments on several of the strategic issues that AMCs should address if they wish to successfully expand overseas
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