728 research outputs found
Using computer‐based tests for information science
Computer‐based tests have been used extensively in the Department of Information Science at the University of Portsmouth, both for end‐of‐course examinations and continuous assessment. This paper details the use of computer‐based objective testing as an innovative technique for traditional assessment, and the separate problems of continuous computer‐aided assessment. Results from three years of research have led to plans for future developments within the department, and the paper provides a checklist of considerations regarded as crucial
Designing intelligent computer‐based simulations: A pragmatic approach
This paper examines the design of intelligent multimedia simulations. A case study is presented which uses an approach based in part on intelligent tutoring system design to integrate formative assessment into the learning of clinical decision‐making skills for nursing students. The approach advocated uses a modular design with an integrated intelligent agent within a multimedia simulation. The application was created using an object‐orientated programming language for the multimedia interface (Delphi) and a logic‐based interpreted language (Prolog) to create an expert assessment system. Domain knowledge is also encoded in a Windows help file reducing some of the complexity of the expert system. This approach offers a method for simplifying the production of an intelligent simulation system. The problems developing intelligent tutoring systems are examined and an argument is made for a practical approach to developing intelligent multimedia simulation systems
On the atomic structure of cocaine in solution
Cocaine is an amphiphilic drug which has the ability to cross the blood–brain barrier (BBB). Here, a combination of neutron diffraction and computation has been used to investigate the atomic scale structure of cocaine in aqueous solutions. Both the observed conformation and hydration of cocaine appear to contribute to its ability to cross hydrophobic layers afforded by the BBB, as the average conformation yields a structure which might allow cocaine to shield its hydrophilic regions from a lipophilic environment. Specifically, the carbonyl oxygens and amine group on cocaine, on average, form ~5 bonds with the water molecules in the surrounding solvent, and the top 30% of water molecules within 4 Å of cocaine are localized in the cavity formed by an internal hydrogen bond within the cocaine molecule. This water mediated internal hydrogen bonding suggests a mechanism of interaction between cocaine and the BBB that negates the need for deprotonation prior to interaction with the lipophilic portions of this barrier. This finding also has important implications for understanding how neurologically active molecules are able to interact with both the blood stream and BBB and emphasizes the use of structural measurements in solution in order to understand important biological function.Peer ReviewedPostprint (author's final draft
Structural investigation of graphitic carbon nitride via XRD and neutron diffraction
We thank EPSRC for support through the EPSRC/NSF chemistry programme and the Royal Society for a Wolfson Merit award.Graphitic carbon nitride (g-C3N4) has, since 2009, attracted great attention for its activity as a visible-light-active photocatalyst for hydrogen evolution. Since it was synthesized in 1834, g-C3N4 has been extensively studied both catalytically and structurally. Although its 2D structure seems to have been solved, its 3D crystal structure has not yet been confirmed. This study attempts to solve the 3D structure of graphitic carbon nitride by means of X-ray diffraction and of neutron scattering. Initially, various structural models are considered and their XRD patterns compared to the measured one. After selecting possible candidates as g-C3N4 structure, neutron scattering is employed to identify the best model that describes the 3D structure of graphitic carbon nitride. Parallel chains of tri-s-triazine units organized in layers with an A–B stacking motif are found to describe the structure of the synthesized graphitic carbon nitride well. A misalignment of the layers is favorable because of the decreased π–π repulsive interlayer interactions.PostprintPostprintPeer reviewe
Dihydrogen: Vs. hydrogen bonding in the solvation of ammonia borane by tetrahydrofuran and liquid ammonia
The solvation structures of two systems rich in hydrogen and dihydrogen bonding interactions have been studied in detail experimentally through neutron diffraction with hydrogen/deuterium isotopic substitution. The results were analysed by an atomistic Monte Carlo simulation employing refinement to the experimental scattering data. The systems studied were the hydrogen storage material ammonia borane (NH 3 BH 3 , AB) dissolved in tetrahydrofuran (THF), and liquid ammonia (NH 3 ), the latter in which AB shows unusually high solubility (260 g AB per 100 g NH 3 ) and potential regeneration properties. The full orientational and positional manner in which AB-AB, AB-THF and AB-NH 3 pairs interact with each other were successfully deciphered from the wide Q-range total neutro n scattering data. This provided an unprecedented level of detail into such highly (di)hydrogen bonding solute-solvent interactions. In particular this allowed insight into the way in which H-B acts as a hydrogen bond acceptor. The (di)hydrogen bonding was naturally determined to dictate the intermolecular interactions, at times negating the otherwise expected tendency for polar molecules to align themselves with anti-parallel dipole moments. Several causes for the extreme solubility of AB in ammonia were determined, including the ability of ammonia to (di)hydrogen bond to both ends of the AB molecule and the small size of the ammonia molecule relative to AB and THF. The AB B-H to ammonia H dihydrogen bond was found to dominate the intermolecular interactions, occurring almost three times more often than any other hydrogen or dihydrogen bond in the system. The favourability of this interaction was seen on the bulk scale by a large decrease in AB clustering in ammonia compared to in the dihydrogen bond-less THF
From Ideas to Practice, Pilots to Strategy: Practical Solutions and Actionable Insights on How to Do Impact Investing
This report is the second publication in the World Economic Forum's Mainstreaming Impact Investing Initiative. The report takes a deeper look at why and how asset owners began to include impact investing in their portfolios and continue to do so today, and how they overcame operational and cultural constraints affecting capital flow. Given that impact investing expertise is spread among dozens if not hundreds of practitioners and academics, the report is a curation of some -- but certainly not all -- of those leading voices. The 15 articles are meant to provide investors, intermediaries and policy-makers with actionable insights on how to incorporate impact investing into their work.The report's goals are to show how mainstream investors and intermediaries have overcome the challenges in the impact investment sector, and to democratize the insights and expertise for anyone and everyone interested in the field. Divided into four main sections, the report contains lessons learned from practitioner's experience, and showcases best practices, organizational structures and innovative instruments that asset owners, asset managers, financial institutions and impact investors have successfully implemented
The reaction of formic acid with RaneyTM copper
The interaction of formic acid with RaneyTM Cu proves to be complex. Rather than the expected generation of a monolayer of bidentate formate, we find the formation of a Cu(II) compound. This process occurs by direct reaction of copper and formic acid; in contrast, previous methods are by solution reaction. This is a rare example of formic acid acting as an oxidant rather than, as more commonly found, a reductant. The combination of diffraction, spectroscopic and computational methods has allowed this unexpected process to be characterized
Social dimensions of invasive plant management: an Alaska case study
Thesis (M.S.) University of Alaska Fairbanks, 2018Uncertainty pervades attempts to identify an efficient management response to the threat of invasive plants. Sources of uncertainty include the paucity of data, measurement errors, variable invasiveness, and unpredictable impacts of the control methods. Rather than relying on this uncertain evidence from the natural sciences, land managers are taking a more participatory approach to invasive plant management to help alleviate risk and share the responsibility of implementation of proactive control and eradication strategies. This research is intended to contribute to this process of social learning by revealing the beliefs that determine stakeholder management preferences in a case study involving an infestation of Vicia cracca (bird vetch) affecting public lands, north of the Arctic Circle, along the Dalton Highway in Alaska. Possible encroachment of this "highly invasive" species upon vulnerable areas of high conservation significance in this rapidly changing, boreal-arctic system has motivated some stakeholders to advocate an aggressive, early response aimed at eradication using herbicides. This case study applies social-psychological theory in the study of the interactions between human behavior and human outcomes. Interior Alaska stakeholders were engaged in a survey to measure support for a scenario involving the use of herbicides to control the highly-invasive species, Vicia cracca (bird vetch), which has spread north along a road corridor north of the Arctic Circle. Respondents were asked a series of questions about the "likelihood" and "acceptability" of the possible outcomes. The survey results aligned with the expectation that attitudes predict management preference, however the beliefs that influence these attitudes were more complicated than expected. The results address the feedbacks anticipated between the human outcomes and human behavior in the social template within the broader system context that are critical to management success. The purpose is to utilize the results of this specific case study to facilitate the development of ongoing research questions that are generalizable to other affected boreal-arctic ecosystems, regionally and globally.Chapter 1: Introduction -- Social-ecological system dynamics -- Chapter 2: Stakeholder beliefs and attitudes toward invasive plant management and herbicides: an Alaska public lands study -- Chapter 3: Conclusion
Photolytic and thermolytic decomposition products from iron pentacarbonyl adsorbed on Y zeolite
Zeolite supported iron systems obtained by photolysis and thermolysis of Fe(CO)5/Na---Y adducts are characterized via evaluation of the respective magnetic isotherms taken with a FONER magnetometer at T = 4.2 K. Thermolysis under fast heating in inert gas and under fluidized shallow bed conditions completes within a few minutes at not, vert, similar 500 K, and gives iron clusters of which at least 70 to 90 wt% is smaller than 1 nm. Prolonged photolysis at 290 K in the same fluidized bed conditions does not result in the formation of ‘naked’ iron(O) clusters, but gives a limited fraction of magnetically coupled Fex(CO)y entities. Photodimerization cannot be excluded to be the main reaction path
Reducing Hopelessness in Patients with Parkinson’s Disease: Educational Intervention
Reducing Hopelessness in Patients with Parkinson’s Disease: Educational Intervention
BACKGROUND: Parkinson’s disease (PD), features several non-motor manifestations, including cognitive dysfunction, which impacts patients and their families. Depression, hopelessness, and anxiety are all prevalent in the psychiatric conditions of PD. In fact, at least 50% of those diagnosed with PD will experience some sort of depression, hopelessness, or anxiety disorder after diagnosis (Ray & Agarwal, 2020). The specific purpose of this project was to help patients with PD diagnosis feel less hopeless and more resilient when coping with their symptoms of PD.
LOCAL PROBLEM: The project setting was a rural integrated health clinic. Patients with PD within the patient population are approximately 10 patients. These patients attend a PD support group meeting. The patients with this diagnosis who come to the clinic for their primary care have expressed concerns about their feelings of hopelessness and lack of education on the disease process and symptom management.
METHODS: Levin’s Evidence-Based Practice Improvement Model was the guiding framework for this project. The selection of a questionnaire and the final process for educational implementation and clinical decision-making were determined using PDSA (plan-do-study-act) cycles. Pre-education and post-education were measured, as were the use of the tool.
INTERVENTIONS: The project leader educated the group on the use of movement therapies and the Mediterranean diet to increase symptom control. The 20-question Beck’s Hopelessness scale was used for data collection to assess the symptoms of hopelessness and to track improvement after education on the given topics. A pre-and post-questionnaire was given to each participant and compared to receive the project results.
RESULTS: A paired-sample t-test was used to determine whether there was a statistically significant mean difference between the pre-education hopelessness scores and post-education hopelessness scores. Participants had lower hopelessness scores after the education (M = 3.85, SD = 4.34) as opposed to before the education (M = 5.77, SD = 4.76), a statistically significant mean decrease of 1.92, 95% CI [0.68, 3.17], t(12) = 3.366, p = .006.
CONCLUSIONS: Participants had lower hopelessness scores after the education as opposed to before the education, a statistically significant mean decrease. Educational interventions made this patient population feel heard and understood. There needs to be an increase in the PD support groups and the number of times they can meet per month. The support group needs more professionals willing to come in and speak with the group on symptom control
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