Showing papers by "University of Hartford published in 2019"

Kink-Kink and Kink-Antikink Interactions with Long-Range Tails.

Abstract: In this Letter, we address the long-range interaction between kinks and antikinks, as well as kinks and kinks, in φ^{2n+4} field theories for n>1. The kink-antikink interaction is generically attractive, while the kink-kink interaction is generically repulsive. We find that the force of interaction decays with the 2n/(n-1)th power of their separation, and we identify the general prefactor for arbitrary n. Importantly, we test the resulting mathematical prediction with detailed numerical simulations of the dynamic field equation, and obtain good agreement between theory and numerics for the cases of n=2 (φ^{8} model), n=3 (φ^{10} model), and n=4 (φ^{12} model).

Long-range interactions of kinks

Abstract: We present a computational analysis of the long-range interactions of solitary waves in higher-order field theories. Our vehicle of choice is the ${\ensuremath{\varphi}}^{8}$ field theory, although we explore similar issues in example ${\ensuremath{\varphi}}^{10}$ and ${\ensuremath{\varphi}}^{12}$ models. In particular, we discuss the fundamental differences between the latter higher-order models and the standard ${\ensuremath{\varphi}}^{4}$ model. Upon establishing the power-law asymptotics of the model's solutions' approach towards one of the steady states, we make the case that such asymptotics require particular care in setting up multisoliton initial conditions. A naive implementation of additive or multiplicative ans\"atze gives rise to highly pronounced radiation effects and eventually leads to the illusion of a repulsive interaction between a kink and an antikink in such higher-order field theories. We propose and compare several methods for how to ``distill'' the initial data into suitable ans\"atze, and we show how these approaches capture the attractive nature of interactions between the topological solitons in the presence of power-law tails (long-range interactions). This development paves the way for a systematic examination of solitary wave interactions in higher-order field theories and raises some intriguing questions regarding potential experimental observations of such interactions. As an Appendix, we present an analysis of kink-antikink interactions in the example models via the method of collective coordinates.

Hallucinations Beyond Voices: A Conceptual Review of the Phenomenology of Altered Perception in Psychosis.

Abstract: Recent psychiatric research and treatment initiatives have tended to move away from traditional diagnostic categories and have focused instead on transdiagnostic phenomena, such as hallucinations. However, this emphasis on isolated experiences may artificially limit the definition of such phenomena and ignore the rich, complex, and dynamic changes occurring simultaneously in other domains of experience. This article reviews the literature on a range of experiential features associated with psychosis, with a focus on their relevance for hallucinations. Phenomenological research on changes in cognition, perception, selfhood and reality, temporality, interpersonal experience, and embodiment are discussed, along with their implications for traditional conceptualizations of hallucinations. We then discuss several phenomenological and neurocognitive theories, as well as the potential impact of trauma on these phenomena. Hallucinations are suggested to be an equifinal outcome of multiple genetic, neurocognitive, subjective, and social processes; by grouping them together under a single, operationalizable definition, meaningful differences in etiology and phenomenology may be ignored. It is suggested that future research efforts strive to incorporate a broader range of experiential alterations, potentially expanding on traditional definitions of hallucinations. Relevance for clinical practice, including emphasizing phenomenologically responsive techniques and developing targeted new therapies, is discussed.

How Should AI Be Developed, Validated, and Implemented in Patient Care?

Abstract: Should an artificial intelligence (AI) program that appears to have a better success rate than human pathologists be used to replace or augment humans in detecting cancer cells? We argue that some concerns-the "black-box" problem (ie, the unknowability of how output is derived from input) and automation bias (overreliance on clinical decision support systems)-are not significant from a patient's perspective but that expertise in AI is required to properly evaluate test results.

Mutual-Preference Driven Truthful Auction Mechanism in Mobile Crowdsensing

Abstract: Motivating the mobile users to participate in sensing services for efficient data generation and collection is one of the most critical issues in Mobile Crowdsensing Systems (MCSs). Auction based mechanisms are seen to be promising and effective solutions to incentivize mobile users. However, price is not the unique factor dominating participants' contribution in MCSs. Participant's preference for different sensing tasks is also a pivotal factor which should be considered in the auction mechanisms as assigning the least favorite tasks discourages them to participate in future sensing tasks. Unfortunately, participant's preference has been overlooked by most existing works, which motivates us to fill this gap in this paper. We first propose a new concept "mutual preference degree" to capture participant's preference and then design a preference-based auction mechanism (PreAM) to simultaneously guarantee individual rationality, budget feasibility, preference truthfulness, and price truthfulness. Finally, both the theoretical analysis and simulation results demonstrate the effectiveness of PreAM.

The Efficacy of Hypnosis as a Treatment for Anxiety: A Meta-Analysis

Abstract: This meta-analysis quantifies the effectiveness of hypnosis in treating anxiety. Included studies were required to utilize a between-subjects or mixed-model design in which a hypnosis intervention was compared with a control condition in alleviating the symptoms of anxiety. Of 399 records screened, 15 studies incorporating 17 trials of hypnosis met the inclusion criteria. At the end of active treatment, 17 trials produced a mean weighted effect size of 0.79 (p ≤ .001), indicating the average participant receiving hypnosis reduced anxiety more than about 79% of control participants. At the longest follow-up, seven trials yielded a mean weighted effect size of 0.99 (p ≤ .001), demonstrating the average participant treated with hypnosis improved more than about 84% of control participants. Hypnosis was more effective in reducing anxiety when combined with other psychological interventions than when used as a stand-alone treatment.

Effects of flow recirculation on unmanned aircraft system (UAS) acoustic measurements in closed anechoic chambers.

Abstract: An experimental campaign was undertaken to identify the effects of flow recirculation on an isolated rotor's acoustic emissions in a closed anechoic chamber. It is shown that flow recirculation results in a significant increase in higher harmonic noise, with an increase of more than 15 dB in some harmonics. This increase in noise is due to the nature of testing in a closed facility and does not represent the acoustic emissions of a similar rotor in hovering flight outdoors. Future measurements of rotors and full unmanned aerial vehicles in closed anechoic chambers must acknowledge recirculation effects and attempt to mitigate the effect on reported measurements.

A Value-Driven Eldercare Robot: Virtual and Physical Instantiations of a Case-Supported Principle-Based Behavior Paradigm

Abstract: In this paper, a case-supported principle-based behavior paradigm is proposed to help ensure ethical behavior of autonomous machines. We argue that ethically significant behavior of autonomous systems should be guided by explicit ethical principles determined through a consensus of ethicists. Such a consensus is likely to emerge in many areas in which autonomous systems are apt to be deployed and for the actions they are liable to undertake. We believe that this is the case since we are more likely to agree on how machines ought to treat us than on how human beings ought to treat one another. Given such a consensus, particular cases of ethical dilemmas where ethicists agree on the ethically relevant features and the right course of action can be used to help discover principles that balance these features when they are in conflict. Such principles not only help ensure ethical behavior of complex and dynamic systems but also can serve as a basis for justification of this behavior. The requirements, methods, implementation, and evaluation components of the paradigm are detailed as well as its instantiation in both a simulated and real robot functioning in the domain of eldercare.

Systematic review of psychosocial factors associated with evictions.

Abstract: Evictions from rented accommodations are a common pathway to homelessness and can negatively impact the lives of individuals and communities worldwide. There have been only few interventions developed to address evictions, and it is important to first understand factors associated with evictions. This systematic review included all available peer-reviewed articles on the topic published in the international literature from 1900 to 2017 and identified 10 peer-reviewed studies of evictions conducted in the United States, Canada, Amsterdam and Britain. From these studies, four categories of factors associated with evictions were identified. These factors were financial hardships, sociodemographic characteristics, substance use and other health problems. While many studies had large sample sizes, the majority of studies were cross-sectional. Together, our review found that there were several salient factors known to be associated with evictions which may benefit from intervention. However, more prospective studies on evictions and development of interventions are needed.

Balancing Work, School, and Personal Life among Graduate Students: a Positive Psychology Approach

Abstract: Graduate students are faced with an array of responsibilities in their personal and professional lives, yet little research has explored how working students maintain a sense of well-being while managing work, school, and personal-life. Drawing on conservation of resources theory and work-family enrichment theory, we explored personal, psychological resources that increase enrichment and decrease conflict, and in turn decrease perceptions of stress. In a study of 231 employed graduate students, we found that mindfulness was negatively related to stress via perceptions of conflict and enrichment, whereas self-compassion, resilience, and recovery experience were negatively related to stress, but only through conflict, not enrichment. These findings suggest that graduate students who are able to be “in the moment” may experience higher levels of well-being, in part due to greater enrichment and lower conflict.

Multi-Scale Feedbacks for Large-Scale Coordination in Self-Systems

Abstract: Multi-scale structures, or hierarchies, are prevalent in large-scale dynamic systems, from inert matter to living and artificial systems, and systems-of-systems. Yet, a general theory helping to understand and develop multi-scale systems is still missing. This paper identifies common design aspects and variants, and synthesises them via a novel design pattern - Multi-Scale Feedbacks - to help adaptive coordination in large-scale systems. It also suggests relations between design choices and qualitative properties. The proposed pattern was distilled from a cross-domain study, including particle physics, molecular biology, neuroscience, insect and human organisations, ecosystems, autonomous control and systems-of-systems.

Prospective memory intervention using visual imagery in individuals with brain injury.

Abstract: Prospective memory deficits are common after brain injury and can create impediments to independent living. Most approaches to management of such deficits are compensatory, such as the use of notebooks or electronic devices. While these can be effective, a restorative approach, in theory, could lead to greater generalisation of treatment. In the current study a metacognitive technique, using visual imagery, was employed under conditions of rote repetition and spaced retrieval. Treatment was provided in an AB-BA crossover design with A as the active treatment and B as a no-treatment attention control to 20 individuals with brain injury. A group of 20 healthy participants served to control for effects of re-testing. Individuals with brain injury demonstrated improvement on the main outcome measure of prospective memory, the Memory for Intentions Screening Test, only after the active treatment condition. In addition, some generalisation of treatment was measured in daily life. Moreover, treatment gains were maintained for one year after treatment was completed.

"Making weight" during military service is related to binge eating and eating pathology for veterans later in life.

Abstract: “Making weight” behaviors are unhealthy weight control strategies intended to reduce weight in an effort to meet weight requirements. This study aimed to examine a brief measure of making weight and to investigate the relationship between making weight and weight, binge eating, and eating pathology later in life. Participants were veterans [N = 120, mean age 61.7, mean body mass index (BMI) 38.0, 89.2% male, 74.2% Caucasian] who were overweight/obese and seeking weight management treatment. Participants completed the making weight inventory (MWI), a measure of making weight behaviors engaged in during military service, and validated measures of eating behavior. Analyses compared participants who engaged in at least one making weight behavior (MWI+) versus those who did not (MWI−). The MWI had good internal consistency. One-third of participants were MWI+ and two-thirds were MWI−. The most frequently reported behavior was excessive exercise, reported in one-quarter of the sample, followed by fasting/skipping meals, sauna/rubber suit, laxatives, diuretics, and vomiting. MWI+ participants were significantly more likely to be in a younger cohort of veterans, to be an ethnic/racial minority, and to engage in current maladaptive eating behaviors, including binge eating, vomiting, emotional eating, food addiction, and night eating, compared to the MWI− group. Groups did not differ on BMI. One-third of veterans who were overweight/obese screened positive for engaging in making weight behaviors during military service. Findings provide evidence that efforts to “make weight” are related to binge eating and eating pathology later in life. Future research and clinical efforts should address how to best eliminate unhealthy weight control strategies in military service while also supporting healthy weight management efforts.

Contrasting Various Notions of Convergence in Geometric Analysis

Abstract: We explore the distinctions between $L^p$ convergence of metric tensors on a fixed Riemannian manifold versus Gromov-Hausdorff, uniform, and intrinsic flat convergence of the corresponding sequence of metric spaces. We provide a number of examples which demonstrate these notions of convergence do not agree even for two dimensional warped product manifolds with warping functions converging in the $L^p$ sense. We then prove a theorem which requires $L^p$ bounds from above and $C^0$ bounds from below on the warping functions to obtain enough control for all these limits to agree.

From Computation to the First-Person: Auditory-Verbal Hallucinations and Delusions of Thought Interference in Schizophrenia-Spectrum Psychoses.

Abstract: Schizophrenia-spectrum psychoses are highly complex and heterogeneous disorders that necessitate multiple lines of scientific inquiry and levels of explanation. In recent years, both computational and phenomenological approaches to the understanding of mental illness have received much interest, and significant progress has been made in both fields. However, there has been relatively little progress bridging investigations in these seemingly disparate fields. In this conceptual review and collaborative project from the 4th Meeting of the International Consortium on Hallucination Research, we aim to facilitate the beginning of such dialogue between fields and put forward the argument that computational psychiatry and phenomenology can in fact inform each other, rather than being viewed as isolated or even incompatible approaches. We begin with an overview of phenomenological observations on the interrelationships between auditory-verbal hallucinations (AVH) and delusional thoughts in general, before moving on to review several theoretical frameworks and empirical findings in the computational modeling of AVH. We then relate the computational models to the phenomenological accounts, with a special focus on AVH and delusions that involve the senses of agency and ownership of thought (delusions of thought interference). Finally, we offer some tentative directions for future research, emphasizing the importance of a mutual understanding between separate lines of inquiry.

Donor Influence on Long-Term Innovation Within Nonprofit Organizations:

Abstract: We examine how donors influence nonprofit long-term product innovation by estimating a fixed-effects model using longitudinal data on a sample of nonprofit organizations. Innovation requires multiy...

Global supply chain networks and tariff rate quotas: equilibrium analysis with application to agricultural products

Abstract: In this paper, we develop a global supply chain network model in which profit-maximizing firms engage in competition in the production and distribution of products in the presence of quantitative trade policy instruments in the form of tariff rate quotas. Tariff rate quotas are two-tiered tariffs, in which a lower in-quota tariff is applied to the units of imports until a quota or upper bound is attained and then a higher over-quota tariff is applied to all subsequent imports. They are utilized to protect domestic producers in the case of a wide range of products, from agricultural ones to fabrics and even steel, and can be challenging to formulate. We construct the governing set of novel equilibrium conditions associated with the product flows and Lagrange multipliers, which correspond to quota rent equivalents, and derive the variational inequality formulation. Qualitative properties are presented along with an effective algorithm, which is then applied to compute solutions to numerical examples comprising an agricultural product case study on avocados and global trade. This work is the first to model and solve general, competitive supply chain network problems consisting of oligopolistic firms with multiple production sites and demand markets in multiple countries subject to tariff rate quotas.

Significance of non-uniform scour on the seismic performance of bridges

Abstract: Multiple hazards such as flood-induced scour followed by earthquakes can adversely impact the performance of bridges spanning over waterways. Scour is the erosion of soil around the foundation of b...

Ordinary Differential Equations: From Calculus to Dynamical Systems

Abstract: Preface Sample course outline 1. Introduction to differential equations 2. First-order differential equations 3. Second-order differential equations 4. Linear systems of first-order differential equations 5. Geometry of autonomous systems 6. Laplace transforms Appendix A. Answers to odd-numbered exercises Appendix B. Derivative and integral formulas Appendix C. Cofactor method for determinants Appendix D. Cramer's rule for solving systems of linear equations Appendix E. The Wronskian Appendix F. Table of Laplace transforms Index About the author.

The euphemism of good practice or advanced nursing practice

Abstract: Objective: To analyze how the focus given nowadays in our country to good practices in the care process as centrality of Nursing offers support to the discussion about the expansion of nurses' performance through advanced practices. Method: This is a theoretical-reflexive article, based on critical reading of studies on the subject, focused on the need to discuss the training of nurses in the perspective of their role expansion. Results: The arguments for both subjects, based on the discussion of the theoretical reference of the two themes: good practices or practice based on evidences, and advanced practice nursing. Final considerations and implications for practice: It is proposed that, in addition to good practices, undoubtedly necessary, the appropriation of advanced nursing practice and the debate about its adoption in the country are fundamental to the new professional challenges facing nursing and the training of human resources for the Unified Health System. The arguments presented lead to the knowledge of the nursing topic of recent dissemination in Brazil, the advanced nursing practice, which can substantially change the nurses' performance in our reality.

Properties of the Null Distance and Spacetime Convergence

Abstract: The null distance for Lorentzian manifolds was recently introduced by Sormani and Vega. Under mild assumptions on the time function of the spacetime, the null distance gives rise to an intrinsic, conformally invariant metric that induces the manifold topology. We show when warped products of low regularity and globally hyperbolic spacetimes endowed with the null distance are (local) integral current spaces. This metric and integral current structure sets the stage for investigating convergence analogous to Riemannian geometry. Our main theorem is a general convergence result for warped product spacetimes relating uniform, Gromov--Hausdorff and Sormani--Wenger intrinsic flat convergence of the corresponding null distances. In addition, we show that non-uniform convergence of warping functions in general leads to distinct limiting behavior, such as limits that disagree.

Breaking the Silence: The Phenomenology of the Female High School Band Director:

Abstract: The purpose of this study was to investigate the phenomenology of the female high school band director (FHSBD). In order to achieve a sample for regional maximum variation, one FHSBD from each coun...

Time is on the Immune System's Side, Yes it is

Abstract: From bacteria to mammals, nearly all organisms have adapted their physiology and behavior to a daily rhythm. These circadian (daily) rhythms influence virtually all aspects of physiological architecture (i.e., from gene expression to organismal behavior). Therefore, it is not surprising that several features of the immune response are regulated in a time-of-day dependent manner. The field of chrono-immunology has expanded tremendously over the past decade. In this abridged review, we present studies from the past five years that have revealed new parameters of the immune system that demonstrate daily variations in the control of pathogens and response to microbial components. These studies analyzed how the disruption of circadian rhythms impairs immune function, how microbial components alter the circadian clock, and how immune responses demonstrate daily variations in human subjects. Further elucidating the intricate connections between the circadian clock and the immune system will hopefully provide opportunities for chrono-immunotherapy in disease treatment and prevention.

Building a theory of communication and ethnopolitical conflict

Abstract: Coherent development of theories of ethnopolitical conflict has been slow and scattered. Moreover, the role of communication has been seriously neglected. I theorize ethnopolitical conflict along t...

Elevated nitrogen deposition may advance invasive weed, Solidago canadensis, in calcareous soils

Abstract: Change in nitrogen (N) availability regulates phosphorus (P) acquisition and potentially alters the competition among native species and invasive weeds. This study determines how current and projected N deposition affect the growth, the intraspecific and interspecific competitive ability of native and invasive plants in calcareous soils with low P availability. A controlled greenhouse experiment was conducted using sparingly soluble hydroxyapatite (HAP) to simulate the calcareous soils with low P availability. The growth and competitive intensity between an invasive weed (Solidago canadensis) and a native weed (Pterocypsela laciniata) exposed to two levels of N addition representative of current and future N deposition in China were experimentally determined. P acquisition and the growth of both S. canadensis and P. laciniata growing alone significantly increased with increasing N level. However, the effect of N addition was reduced when intraspecific or interspecific competition existed. N addition altered the competitive relationship between S. canadensis and P. laciniata allowing S. canadensis to out-compete P. laciniata due to variation in P acquisition from HAP. Elevated N deposition might assist the invasion of S. canadensis in the widely distributed calcareous soils under environmental changes.

Social anxiety, cortisol, and early-stage friendship:

Abstract: Socially anxious people report less closeness to others, but very little research has examined how social anxiety is related to closeness in real-time social interactions. The present study investi...

The Multidimensionality of Workplace Incivility: Cross-Cultural Evidence

Abstract: Workplace incivility is prevalent around the world and can be costly for both employees and employers. The majority of past research, however, has been conducted in Western societies using unidimensional measures. The present study used the stressor–strain framework to develop a multidimensional sca