Structure and Functionality of Novel Nanocomposite Granules for a Pressure-Sensitive Ink with Applications in Touchscreen Technologies

Tactile sensors are now ubiquitous within human-computer interactions, where mouse and keyboard functionality can be replaced with a trackpad or touchscreen sensor. In most technologies the sensor can detect the touch location only, with no information given on the force of the touch. In this thesis, functional components of a novel nanocomposite ink are developed, which when printed, form a pressure-sensitive interface which can detect both touch location and touch force. The physical basis of the force-sensitive response is investigated for the touchscreen sensor as a whole, as well as the intrinsic force-sensitivity of the ink components. In an earlier form the nanocomposite ink, that was the starting point of this study, contained agglomerates of conductive nanoparticles which were formed during blending of the ink, and provided the electrical functionality of the sensor. Here, novel nanocomposite granules were pre-fabricated prior to inclusion in the ink. The granules were designed such that they exhibited well-defined size, structure and strength. Control of these parameters was achieved through selection of the granule constituents, as well as the energy and duration of the granulation process. When incorporated into the ink and screen-printed to form a pressure-sensitive layer in a touchscreen test device, the functional performance could be assessed. Sensors containing pre-formed granules showed improved optical transmission, compared to sensors containing the same mass loading of nanoparticles forming spontaneous agglomerates. Agglomerates tend to create a larger number of small scattering centres which scatter light to larger angles. The spatial variation in the force-resistance response, as well as the sensitivity of this response, was also linked to the distribution of the granules within the pressure-sensitive layer. The physical basis of the force-resistance response is two-fold. Firstly, mathematical simulations showed that deflection of the upper electrode increased the number of granules contacted with increasing applied force and therefore decreased the resistance through the sensor. Secondly, a force-sensitive resistance of the granules themselves was also observed at high forces. Analysis of the non-linear current-voltage characteristics suggested the presence of non-linear conduction pathways within the granules. Using a random resistor network model, the non-linear current contribution decreased after approximately 0.7 N force. To understand this effect, a model based on the physical basis of quantum tunnelling mechanisms was also applied, however this provided a poor fit to the data and no further understanding could be gained

Extinction correction and on-sky calibration of SCUBA-2

Commissioning of SCUBA-2 included a program of skydips and observations of calibration sources intended to be folded into regular observing as standard methods of source flux calibration and to monitor the atmospheric opacity and stability. During commissioning, it was found that these methods could also be utilised to characterise the fundamental instrument response to sky noise and astronomical signals. Novel techniques for analysing on-sky performance and atmospheric conditions are presented, along with results from the calibration observations and skydips.Comment: 10 pages, 7 figure

Extirpation Despite Regulation? Environmental Assessment and Caribou

Many caribou populations in Canada face extirpation despite dozens of provincial and federal legislative instruments designed to protect them. How are industrial developments that impact caribou justified and permitted despite governments\u27 commitments to caribou protection? Toward an answer, this paper scrutinizes an approval process for major projects in Canada: environmental assessment (EA). We identify 65 EAs for major projects with potentially significant adverse impacts for caribou—all projects but one were approved. The results show that most projects were approved on the basis of proposed mitigation measures that promise to render adverse effects “insignificant”; yet mitigation effectiveness is largely unknown. Further, several projects were approved even though mitigation measures were insufficient, citing public or national interest. Finally, some projects\u27 approval rested in part on scientific claims that the project area is already degraded or absent of caribou. Based on these findings, EA is failing caribou, acting as a means by which the state licenses major developments with potentially significant adverse effects for caribou, with a pretense of protection. The failure stems in part from a broader tension within the state that manifests in EA: a tension between the state\u27s roles promoting economic growth and protecting against this growth\u27s negative effects. Recognition of this tension needs to be more central to conservation biology

Analysis of Nurses’ Perceptions of Their Role in a Multidisciplinary Team

A better understanding of task allocation for the registered nurse (RN) within the scope of the multidisciplinary care team model is required. Patients, healthcare staff, and medical facilities that utilize RNs in multidisciplinary care teams will benefit from improved role identification. A multidisciplinary care team consists of a variety of health care professionals and without role identification, confusion, miscommunication, and negative patient outcomes can occur. A literature review demonstrated that a gap in knowledge existed related to task allocation and role identification of RNs within a multidisciplinary care team. The purpose of this study was to evaluate RNs’ scope of practice within a multidisciplinary care team of an acute care medical center and identify a new theory regarding RNs’ perceptions of their role. A grounded theory approach was used to explore and reveal these perceived role identifications through the lens of the accountability theory. The research questions and the guided interview explored RNs’ self-perceived role identifications that have shaped RNs’ expectations of their scope within the multidisciplinary care team model. The results found nurses to be experts of patient care and that the nursing role has a 24/7 responsibility while being the closest, most personal role to the patient, thus, the RN feels accountable for all the needs to the patient, even if the needs or actions are outside of the nursing assigned role or tasks. From these results emerged a new theory, the perpetual accountability theory. Identified recommendations regarding RNs’ roles and their utilization within the multidisciplinary care teams allow a positive social change of greater success at delivering best practices and optimum patient outcomes

Intimate Mediations of For‐Profit Conservation Finance:Waste, Improvement, and Accumulation

How to understand the marriage between accumulation and conservation? The paper draws from extensive research into one value chain, from the advisor in New York City to a wildlife‐friendly cattle business in Kenya. Making this enterprise return in money requires intimate and relentless efforts to transform wasteful conduct across a range of institutions and people; we focus on the attempted production of NGO economicus, homo economicus plus, and bos Taurus economicus. Drawing from feminist and postcolonial theorists of capitalism, we emphasise how green capitalist value production does not always hinge on extinguishing other‐than‐capitalist‐social relations but rather attempts to mobilise and harness such differences, including non‐profit‐seeking values, logics and relations. The paper concludes by reflecting on the temporal challenges facing for‐profit conservation finance, including those posed by previous regimes of accumulation that it relies on but also wants to overcome

The COVID-19 pandemic and the right to health of people who use drugs

Context: According to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) people who inject drugs (PWID) make up a significant part of the population that needs to be looked after to eliminate infectious diseases such as those caused by HIV and HCV. This situation has been exacerbated by the COVID-19 pandemic. As COVID-19 rapidly spread across the globe, governments implemented various prevention measures which not only caused an increase in problem drug use (PDU) because of their negative impact on mental health and socioeconomic conditions but also prompted a decrease in drug services provided. Therefore, new challenges appeared, such as increased demand for drugs and diversification of clients, and new needs. Nevertheless, in clear contradiction to what was needed, the EMCDDA’s initial reports suggested that there was a decline in European drug services both in providing treatment and harm reduction interventions. COVID-19 increased the need to access drug services, healthcare, and support services creating an increased demand for opioid substitution therapy and other medication. Thus, comprehensive, and sustainable policies are needed to combat the public health threats associated with these challenges and to ensure the continuity of care. Policy Options: The challenging circumstances brought by the COVID-19 pandemic require policymakers need to take action to build capacity and resiliency for those facing drug-related health and social problems. These should include the adoption of integrated strategies that combine drug consumption rooms, substance-specific therapies, provision of free needles and naloxone, primary healthcare, and social support. Recommendations: The creation of an integrated drug policy framework addressed to European Union member states is necessary to create robust drug services capable of surviving a crisis. This is guided by a relevant policy design and implementation framework, alongside tangible action principles in line with low-threshold service provision. &nbsp

A new era of wide-field submillimetre imaging: on-sky performance of SCUBA-2

SCUBA-2 is the largest submillimetre wide-field bolometric camera ever built. This 43 square arc-minute field-of-view instrument operates at two wavelengths (850 and 450 microns) and has been installed on the James Clerk Maxwell Telescope on Mauna Kea, Hawaii. SCUBA-2 has been successfully commissioned and operational for general science since October 2011. This paper presents an overview of the on-sky performance of the instrument during and since commissioning in mid-2011. The on-sky noise characteristics and NEPs of the 450 and 850 micron arrays, with average yields of approximately 3400 bolometers at each wavelength, will be shown. The observing modes of the instrument and the on-sky calibration techniques are described. The culmination of these efforts has resulted in a scientifically powerful mapping camera with sensitivities that allow a square degree of sky to be mapped to 10 mJy/beam rms at 850 micron in 2 hours and 60 mJy/beam rms at 450 micron in 5 hours in the best weather.Comment: 18 pages, 15 figures.SPIE Conference series 8452, Millimetre, Submillimetre and Far-infrared Detectors and Instrumentation for Astronomy VI 201

Dopaminergic systems create reward seeking despite adverse consequences

Resource-seeking behaviours are ordinarily constrained by physiological needs and threats of danger, and the loss of these controls is associated with pathological reward seeking1. Although dysfunction of the dopaminergic valuation system of the brain is known to contribute towards unconstrained reward seeking2,3, the underlying reasons for this behaviour are unclear. Here we describe dopaminergic neural mechanisms that produce reward seeking despite adverse consequences in Drosophila melanogaster. Odours paired with optogenetic activation of a defined subset of reward-encoding dopaminergic neurons become cues that starved flies seek while neglecting food and enduring electric shock punishment. Unconstrained seeking of reward is not observed after learning with sugar or synthetic engagement of other dopaminergic neuron populations. Antagonism between reward-encoding and punishment-encoding dopaminergic neurons accounts for the perseverance of reward seeking despite punishment, whereas synthetic engagement of the reward-encoding dopaminergic neurons also impairs the ordinary need-dependent dopaminergic valuation of available food. Connectome analyses reveal that the population of reward-encoding dopaminergic neurons receives highly heterogeneous input, consistent with parallel representation of diverse rewards, and recordings demonstrate state-specific gating and satiety-related signals. We propose that a similar dopaminergic valuation system dysfunction is likely to contribute to maladaptive seeking of rewards by mammals

Dopaminergic systems create reward seeking despite adverse consequences

Resource-seeking behaviours are ordinarily constrained by physiological needs and threats of danger, and the loss of these controls is associated with pathological reward seeking1. Although dysfunction of the dopaminergic valuation system of the brain is known to contribute towards unconstrained reward seeking2,3, the underlying reasons for this behaviour are unclear. Here we describe dopaminergic neural mechanisms that produce reward seeking despite adverse consequences in Drosophila melanogaster. Odours paired with optogenetic activation of a defined subset of reward-encoding dopaminergic neurons become cues that starved flies seek while neglecting food and enduring electric shock punishment. Unconstrained seeking of reward is not observed after learning with sugar or synthetic engagement of other dopaminergic neuron populations. Antagonism between reward-encoding and punishment-encoding dopaminergic neurons accounts for the perseverance of reward seeking despite punishment, whereas synthetic engagement of the reward-encoding dopaminergic neurons also impairs the ordinary need-dependent dopaminergic valuation of available food. Connectome analyses reveal that the population of reward-encoding dopaminergic neurons receives highly heterogeneous input, consistent with parallel representation of diverse rewards, and recordings demonstrate state-specific gating and satiety-related signals. We propose that a similar dopaminergic valuation system dysfunction is likely to contribute to maladaptive seeking of rewards by mammals