Bidirectional Text Compression in External Memory

Bidirectional compression algorithms work by substituting repeated substrings by references that, unlike in the famous LZ77-scheme, can point to either direction. We present such an algorithm that is particularly suited for an external memory implementation. We evaluate it experimentally on large data sets of size up to 128 GiB (using only 16 GiB of RAM) and show that it is significantly faster than all known LZ77 compressors, while producing a roughly similar number of factors. We also introduce an external memory decompressor for texts compressed with any uni- or bidirectional compression scheme

An Overview of a Grid Architecture for Scientific Computing

This document gives an overview of a Grid testbed architecture proposal for the NorduGrid project. The aim of the project is to establish an inter-Nordic testbed facility for implementation of wide area computing and data handling. The architecture is supposed to define a Grid system suitable for solving data intensive problems at the Large Hadron Collider at CERN. We present the various architecture components needed for such a system. After that we go on to give a description of the dynamics by showing the task flow

Lyndon Arrays Simplified

A Lyndon word is a string that is lexicographically smaller than all of its proper suffixes (e.g., "airbus" is a Lyndon word; "amtrak" is not a Lyndon word because its suffix "ak" is lexicographically smaller than "amtrak"). The Lyndon array (sometimes called Lyndon table) identifies the longest Lyndon prefix of each suffix of a string. It is well known that the Lyndon array of a length-n string can be computed in O(n) time. However, most of the existing algorithms require the suffix array, which has theoretical and practical disadvantages. The only known algorithms that compute the Lyndon array in O(n) time without the suffix array (or similar data structures) do so in a particularly space efficient way (Bille et al., ICALP 2020), or in an online manner (Badkobeh et al., CPM 2022). Due to the additional goals of space efficiency and online computation, these algorithms are complicated in technical detail. Using the main ideas of the aforementioned algorithms, we provide a simpler and easier to understand algorithm that computes the Lyndon array in O(n) time

Mukul Roy Interview

Bio: [by Emily Ellert] Mukul Roy was born in Udupi, India where she was raised by her mother and father [the artist declined to specify what year she was born]. She began college there and finished her first two years, called intermediary. Then she moved to Calcutta with her family and continued studying literature there. During her time in Calcutta, there were various sociopolitical movements occurring and it resulted in a lot of violence and bombings. She met her husband in Calcutta, and in 1966 they moved to England where he was continuing his studies to be a physician. During this time, Mukul quit her studies and focused on being a stay at home mom. After various moves around the U.K., for her husband’s studies, her husband got a job opportunity in Chicago. The couple moved to the South side of Chicago and stayed in an apartment provided by the hospital her husband was studying at. In America, she felt lonely. Her husband was always busy, and she was rather bored as she had a hard time communicating in English. She decided that she wanted to get a camera and that it would be a way for her to communicate without words. After receiving a Nikon camera from her husband, she realized she didn’t know what to do with it. She started to take classes at the Institute of Art (she believes this was the name of the college) that closed down a few semesters after she started. She decided to continue her studies at Columbia College, dabbling in some other media but ultimately sticking with photography. She received her Master’s degree and got her own exhibition at Columbia’s gallery. At first, she was mostly taking pictures of the Chicago Indian community and was documenting various small Indian events in Chicago. She soon began to be recognized and published, with publications such as the Indian Tribune and the Chicago Tribune posting her work. More and more organizations were asking her to take pictures for them, and she began to make money off of her work. Mukul also traveled back to India where she was hit by a huge realization: a lot had changed since she had been gone. She, herself, had changed a lot. Her old friends didn’t consider her part of the community anymore and it had a profound effect on her. She began to take pictures with a new purpose: to document anything and everything worth documenting. She didn’t want anything to be lost and have nothing she can look back on, and she wanted people to have a documented history of their community, so she pursued her art with a new passion. After returning to Chicago, she was still working mostly in the Indian community, but branching out for certain events. She had little interest in documenting large events because they were already documented by others, but she recognizes that each person has a different perception of events. Many of her works were inspired by Indian women and the lives of Indian families in America. She has since been exhibited at the University of Chicago, the Chicago Historical Society, and the Chicago Cultural Center, as well as being published in many, many, newspapers, magazines, and other various publications. She now lives on the North side of Chicago right on Lake Shore Drive, where she continues to work on projects for her own personal collection

Franz Werfel\u27s Great Dilemma

Frederick C. Ellert investigates Franz Werfel\u27s crisis of faith based on Werfel\u27s Between Heaven and Earth, Paul Among Jews, Barbara, The Song of Bernadette and Star of the Unborn

Leadership Competencies Needed by Future Army Education Services Officers

The purpose of this study was to identify which leadership competencies future Army Continuing Education System Education Services Officers will need to better structure leadership development within that organization. A Delphi survey was sent to 13 Southeast Region Army Education Services Officers (ESOs) and consisted of three rounds: the first two rounds were used to reach a consensus as to what competencies were considered important by the panel of experts, and the last round allowed the panel to rank each selected competency by its level of importance to future Education Services Officers. Using Army Field Manual 6-22, Army Leadership, the Army\u27s eight core competencies and associated components were used to formulate the initial round of 56 Yes or No responses. The first round included two open-ended questions and requested demographic data. Round Two was made up of 24 Yes or No response statements and two open-ended questions. The last round included the final 67 components that were ranked in order of importance on a five-point rating scale (Least Important, Important, Somewhat Important, Very Important, Critical). Using quantitative methods of frequencies and percentages, the results indicated that present Education Services Officers believe that almost all of the competencies listed in Field Manual 6-22 are important for future Education Services Officers. The additional knowledge, skills, abilities, and dispositions that make up the added competency components included: Understands the role of the Army within the Department of Defense; Leads with flexibility; Utilizes strategic planning and decision making methods; Understands budget development and fiscal planning; Identifies personnel and contracting requirements and understands both systems; Open to [learning about] technical, virtual, and Internet-based systems; and Encourages innovation. The information obtained from this study can provide a framework to assist Army leaders, Garrison Commanders, and hiring officials when reviewing applications for future Education Services Officers. Current Army Continuing Education System professionals can also use the data from this study to ensure they have sought out and received the necessary training and development in each competency area and are fully qualified to meet the demands of working as future Education Services Officers

Doctor of Philosophy

dissertationThe maintenance of metabolic homeostasis presents a major challenge to animal biology. Dysregulation of this process is central to the etiology of diabetes and obesity, which have placed an ever-increasing burden on global human health. Nuclear receptors are a family of ligand-regulated transcription factors that play important roles in preventing metabolic dysfunction by coordinating downstream transcriptional programs to support physiological homeostasis. This thesis is focused on one of these nuclear receptors, Hepatocyte Nuclear Factor 4A (HNF4A), which acts as a critical regulator of systemic glucose homeostasis. Mutations in HNF4A were established 20 years ago as the monogenic cause of an inherited form of diabetes called Maturity-Onset Diabetes of the Young 1 (MODY1). The mechanistic link between HNF4A dysfunction and diabetes onset, however, remains unclear. In this dissertation, I present work that provides new insights into the mechanisms by which HNF4 supports physiological homeostasis and prevents diabetes. The fruit fly Drosophila melanogaster provides an ideal system for studies of metabolism and physiology that can guide our understanding of these pathways in mammals. We developed and optimized methods for studies of metabolism in Drosophila to further advance its utility in these efforts. Using these techniques, I investigated potentially conserved roles for Drosophila HNF4 (dHNF4) in supporting development and metabolic homeostasis. Through this work, I discovered that dHNF4 mutants recapitulate hallmark features of MODY1, including hyperglycemia and impaired glucose-stimulated insulin secretion (GSIS). dHNF4 functions in the adult insulin producing cells and the fat body to support GSIS and peripheral glucose clearance during adulthood. These functions are linked to a role for dHNF4 in promoting mitochondrial activity in the mature animal through up-regulation of both nuclear and mitochondrial-encoded genes involved in oxidative phosphorylation (OXPHOS). By extending my analysis to mammals through a collaborative effort with several labs, we uncovered evidence suggesting that the role for HNF4 in supporting mitochondrial function has been conserved through evolution. Taken together, my work has identified HNF4 as an important regulator of mitochondrial activity, and suggests that this function has been conserved through evolution to support normal development, physiology, and metabolic homeostasis