A Unified Multi-Functional Dynamic Spectrum Access Framework: Tutorial, Theory and Multi-GHz Wideband Testbed

Dynamic spectrum access is a must-have ingredient for future sensors that are ideally cognitive. The goal of this paper is a tutorial treatment of wideband cognitive radio and radar—a convergence of (1) algorithms survey, (2) hardware platforms survey, (3) challenges for multi-function (radar/communications) multi-GHz front end, (4) compressed sensing for multi-GHz waveforms—revolutionary A/D, (5) machine learning for cognitive radio/radar, (6) quickest detection, and (7) overlay/underlay cognitive radio waveforms. One focus of this paper is to address the multi-GHz front end, which is the challenge for the next-generation cognitive sensors. The unifying theme of this paper is to spell out the convergence for cognitive radio, radar, and anti-jamming. Moore’s law drives the system functions into digital parts. From a system viewpoint, this paper gives the first comprehensive treatment for the functions and the challenges of this multi-function (wideband) system. This paper brings together the inter-disciplinary knowledge

Structural, mechanistic and functional insight into gliotoxin bis-thiomethylation in Aspergillus fumigatus.

Gliotoxin is an epipolythiodioxopiperazine (ETP) class toxin, contains a disulfide bridge that mediates its toxic effects via redox cycling and is produced by the opportunistic fungal pathogen Aspergillus fumigatus Self-resistance against gliotoxin is effected by the gliotoxin oxidase GliT, and attenuation of gliotoxin biosynthesis is catalysed by gliotoxin S-methyltransferase GtmA. Here we describe the X-ray crystal structures of GtmA-apo (1.66 Å), GtmA complexed to S-adenosylhomocysteine (1.33 Å) and GtmA complexed to S-adenosylmethionine (2.28 Å), providing mechanistic insights into this important biotransformation. We further reveal that simultaneous elimination of the ability of A. fumigatus to dissipate highly reactive dithiol gliotoxin, via deletion of GliT and GtmA, results in the most significant hypersensitivity to exogenous gliotoxin observed to date. Indeed, quantitative proteomic analysis of ΔgliT::ΔgtmA reveals an uncontrolled over-activation of the gli-cluster upon gliotoxin exposure. The data presented herein reveal, for the first time, the extreme risk associated with intracellular dithiol gliotoxin biosynthesis-in the absence of an efficient dismutation capacity. Significantly, a previously concealed protective role for GtmA and functionality of ETP bis-thiomethylation as an ancestral protection strategy against dithiol compounds is now evident

Genetic structure of invasive baby’s breath (Gypsophila paniculata) populations in a Michigan dune system

Invasive species can reduce biodiversity of a system by outcompeting native species for resources, changing the physical characteristics of a habitat, and altering natural disturbance regimes. Coastal sand dune ecosystems are dynamic with elevated levels of disturbance, and as such they are highly susceptible to plant invasions. The topography, geographic distribution of preferred habitat, and disturbance regime in an ecosystem can influence where an invasive plant becomes established, its dispersal patterns, and how densely it grows. One such invasion that is of major concern to the Great Lakes dune systems is baby’s breath (Gypsophila paniculata). The invasion of baby’s breath negatively impacts native species, including rare ones such as Pitcher’s thistle (Cirsium pitcheri). Estimating the genetic variation and structure of invasive populations can lead to a better understanding of the invasion history, and the factors influencing invasion success. Microsatellite genetic markers can be beneficial for estimating levels of diversity present within and among populations. Our research goals were to develop microsatellite primers to analyze invasive populations, quantify the genetic diversity and estimate the genetic structure of these invasive populations of baby’s breath in the Michigan dune system. We identified 16 polymorphic nuclear microsatellite loci for baby’s breath out of 73 loci that successfully amplified from a primer library created using Illumina sequencing technology. We analyzed 12 populations at 14 nuclear and 2 chloroplast microsatellite loci and found moderate genetic diversity, strong genetic structure among the populations (global FST = 0.228), and also among two geographic regions that are separated by the Leelanau peninsula. Results from a Bayesian clustering analysis suggest two main population clusters. Isolation by distance was found over all 12 populations (R = 0.755, P \u3c 0.001) and when only cluster 2 populations were included (R = 0.523, P = 0.030); populations within cluster 1 revealed no significant relationship (R = 0.205, P = 0.494). The results suggest the possibility of at least two separate introduction events to Michigan. These results provide an understanding of the invasion history and factors contributing to invasion success. Management of invasive populations can use this to identify populations of high priority

An Examination of the Cooperativeness of Games in the Context of Culture

Despite being one of the few human-specific types of play that humans of various ages engage in, games are understudied in cross-cultural research. Games are not distributed randomly across cultures and vary with some socio-ecological aspects of human cultures. Previous observational studies suggest that the cooperativeness and egalitarianism of cultural groups is reflected in the games that are played across cultures, but this has yet to be studied using a breadth of method- ological approaches. In this dissertation, I investigate the relationship the cooperativeness of games may have with the cooperativeness of cultural groups and offer one potential avenue as to how and why games are distributed across cultures. This dissertation consists of two main parts. The first part (chapters 2 - 3) focuses on gathering and analyzing descriptions of historical games and cultural levels of cooperation from ethnolinguistic groups on the Austronesian language phylogeny. The second part (chapters 4 - 6) focuses on gathering games, cultural levels of cooperation, and investigating the relationship between games and cultural levels of cooperation by three modern-day cultural groups. In chapter two, I describe the making of the Austronesian Game Taxonomy, an open-access database of game descriptions as gathered from historical, ethnographic, and other sources. I also describe my goal structure coding scheme and apply it to the 907 games in the Austronesian Game Taxonomy. In chapter three, I test the relationship between the goal structure of games from the Austronesian Game Taxonomy and several proxies for cultural levels of cooperation in 25 ethnolin- guistic groups. I find that the cooperativeness of games is negatively related to cultural levels of intra-group conflict and positively related with inter-cultural conflict. The goal structure of games is not associated with the social structure of cultures, nor reliably correlate with measures of interdependence in subsistence. Chapter four provides a detailed description of the three cultures that are the focus of Part two of this dissertation: Hai||om and Ovambo in Namibia, and Germans in Leipzig, Germany. I use three semi-structured interviews to obtain information about the levels of social stratification, intra-group conflict, and inter-cultural conflict experienced by these three groups. Chapter five documents the games played by Hai||om and Ovambo children and adults during my research visit to Namibia. I describe a handful of games with variety of goal structures. I provide the interview used to gather this information for future cross-cultural game collection. In chapter six, I examine the relationship between the preference for games that are cooperative or competitive, and cultural levels of cooperation in three modern-day cultures. I also interview caretakers on their attitudes toward children’s play and games. I find cross-cultural variation in children’s game preferences, but adult game preferences do not vary across cultures. Game preferences do not systematically vary with predicted cultural levels of cooperation. In the general discussion, I discuss my research findings in terms of the relationship between games and cultural levels of cooperation and suggest further improvements for the field of cross-cultural game research. This dissertation provides some evidence that games relate with types of conflict, but not with levels of social stratification nor interdependence in subsistence

2021 Student Symposium Research and Creative Activity Book of Abstracts

The UMaine Student Symposium (UMSS) is an annual event that celebrates undergraduate and graduate student research and creative work. Students from a variety of disciplines present their achievements with video presentations. It’s the ideal occasion for the community to see how UMaine students’ work impacts locally – and beyond. The 2021 Student Symposium Research and Creative Activity Book of Abstracts includes a complete list of student presenters as well as abstracts related to their works

The Future of Humanoid Robots

This book provides state of the art scientific and engineering research findings and developments in the field of humanoid robotics and its applications. It is expected that humanoids will change the way we interact with machines, and will have the ability to blend perfectly into an environment already designed for humans. The book contains chapters that aim to discover the future abilities of humanoid robots by presenting a variety of integrated research in various scientific and engineering fields, such as locomotion, perception, adaptive behavior, human-robot interaction, neuroscience and machine learning. The book is designed to be accessible and practical, with an emphasis on useful information to those working in the fields of robotics, cognitive science, artificial intelligence, computational methods and other fields of science directly or indirectly related to the development and usage of future humanoid robots. The editor of the book has extensive R&D experience, patents, and publications in the area of humanoid robotics, and his experience is reflected in editing the content of the book

Entrepreneurial behaviour and the development of entrepreneurial ecosystems under uncertainty: Essays on regenerative medicine venturing at the university-industry boundary

Entrepreneurial ecosystems are an important economic consideration but remain an understudied phenomenon. In particular, research emphasising the role of the entrepreneur within entrepreneurial ecosystems is scant. Entrepreneurial universities, particularly the commercialisation activities by academic entrepreneurs, contribute to both the emergence and development of entrepreneurial ecosystems at the university-industry (U-I) boundary. Yet, an understanding of the links between university characteristics and micro-level cognition on entrepreneurial ecosystems remains limited. Furthermore, it is not clear how the dynamics of entrepreneurial ecosystems differ across different national geographies. Venture development at the U-I boundary is difficult and uncertain. Entrepreneurs must make decisions under intense ambiguity and make sense of the highly uncertain situation. Nowhere is this more evident than in knowledge and technology-intensive sectors, where venturing relies on entrepreneurial coping responses to uncertainty. However, little is known about how entrepreneurs cope with uncertainty, especially when uncertainty is irreducible. To progress understanding of entrepreneurial behaviour amidst uncertainty, and the emergence and development of entrepreneurial ecosystems at the U-I boundary, venturing in the field of regenerative medicine (regenmed) is investigated. This is a particularly suited study context since regenmed commercialisation activities, which are driven by university-based stem cell research, are highly uncertain and the industry is still in a formative stage.This project explores entrepreneurial behaviour amidst uncertainty and the development of entrepreneurial ecosystems at the U-I boundary. The project comprises of three empirical studies (work packages) that can be read independently, however, together the essays provide an enhanced understanding of entrepreneurial behaviour and the development of entrepreneurial ecosystems at the U-I boundary. Work package 1 reveals how ecosystem participants make sense of venturing processes in a highly uncertain, technology-intensive field. It highlights the development of coping strategies during the sensemaking process, and illustrates an association between university entrepreneurial culture and coping strategies. A model of sensemaking process under uncertainty is presented and a typology of sensemaking types in uncertain ecosystems is proposed. Work package 2 is a cross-national study of entrepreneurial ecosystems in Edinburgh (UK) and Madison (USA). The study investigates the development of entrepreneurial ecosystems around two research-intensive universities, which have a long history in stem cell innovation. The essay highlights the effects of cultural artefacts on micro-level behaviours. The influence of behaviour and cognition on the development of entrepreneurial ecosystems is modelled. This reveals different development paths for similar ecosystems. Work package 3 explores the emergence and development of entrepreneurial ecosystems, and considers how these help drive technology-based economies. More specifically, the study explores technology transfer and contextual factors across three regenmed ecosystems (Edinburgh, Madison, and Moscow) to reveal the emergence of entrepreneurial ecosystems at the U-I boundary. Findings show that ecosystem and venture characteristics emerge from institutional characteristics, micro-level cognition and regional context. Additionally, university culture and entrepreneurial coping strategies generate a typology for spinouts within the ecosystem. Collectively, these three essays reveal novel phenomena explaining how ecosystem actors make sense of uncertainty and how this influences the emergence of entrepreneurial ecosystems at the U-I boundary. Additionally, they reveal the importance of context in the venturing process and in entrepreneurial ecosystem dynamics. This provides important contributions to theories of entrepreneurial behaviour, entrepreneurial ecosystems and technology transfer. These scholarly contributions impart important practical implications