Search results for: Kane Esien
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11

Search results for: Kane Esien

11 Comparison of Different Intraocular Lens Power Calculation Formulas in People With Very High Myopia

Authors: Xia Chen, Yulan Wang

Abstract:

purpose: To compare the accuracy of Haigis, SRK/T, T2, Holladay 1, Hoffer Q, Barrett Universal II, Emmetropia Verifying Optical (EVO) and Kane for intraocular lens power calculation in patients with axial length (AL) ≥ 28 mm. Methods: In this retrospective single-center study, 50 eyes of 41 patients with AL ≥ 28 mm that underwent uneventful cataract surgery were enrolled. The actual postoperative refractive results were compared to the predicted refraction calculated with different formulas (Haigis, SRK/T, T2, Holladay 1, Hoffer Q, Barrett Universal II, EVO and Kane). The mean absolute prediction errors (MAE) 1 month postoperatively were compared. Results: The MAE of different formulas were as follows: Haigis (0.509), SRK/T (0.705), T2 (0.999), Holladay 1 (0.714), Hoffer Q (0.583), Barrett Universal II (0.552), EVO (0.463) and Kane (0.441). No significant difference was found among the different formulas (P = .122). The Kane and EVO formulas achieved the lowest level of mean prediction error (PE) and median absolute error (MedAE) (p < 0.05). Conclusion: The Kane and EVO formulas had a better success rate than others in predicting IOL power in high myopic eyes with AL longer than 28 mm in this study.

Keywords: cataract, power calculation formulas, intraocular lens, long axial length

Procedia PDF Downloads 30
10 Magnetic Properties of Bis-Lanthanoates: Probing Dimer Formation in Crystalline, Liquid and Glassy Compounds Using SQUID Magnetometry

Authors: Kane Esien, Eadaoin McCourt, Peter Nockemann, Soveig Felton

Abstract:

Magnetic ionic liquids (MILs) are a class of ionic liquid incorporating one or more magnetic atoms into the anion or cation of the ionic liquid, endowing the ionic liquid with magnetic properties alongside the existing properties of ionic liquids. MILs have applications in e.g. fluid-fluid separations, electrochemistry, and polymer chemistry. In this study three different types of Bis-Lanthanoates, that exist in different phases, have been synthesised and characterised (Ln = lanthanide): 1) imidazolium lanthanide acetate – [C4Mim]2[Ln2(OAc)8] – forms a crystalline solid at room temperature, 2) phosphonium lanthanide acetate – [P666 14]2[Ln2(OAc)8] – is in a solid glassy state, and 3) phosphonium lanthanide octanoate – [P666 14]2[Ln2(Oct)8] – is an ionic liquid. X-ray diffraction of the crystalline solid imidazolium lanthanide acetate – [C4Mim]2[Ln2(OAc)8] confirm that the Ln(III) ions form dimers, bridged by carboxyl groups, but cannot yield information about samples phosphonium lanthanide acetate – [P666 14]2[Ln2(OAc)8] (glass) and phosphonium lanthanide octanoate – [P666 14]2[Ln2(Oct)8] (ionic liquid) since these lack long-range order. SQUID magnetometry studies show that all three samples have effective magnetic moments consistent with non-interacting Ln(III) ions at room temperature but deviate from this behavior in the same way below 50 K. Through modeling the magnetic response, we are able to show that we have formed magnetic dimers, in all compounds, that are weakly antiferromagnetically interacting

Keywords: dimeric ionic liquids, interactions, SQUID, structure

Procedia PDF Downloads 121
9 Coherence and Cohesion in IELTS Academic Writing: Helping Students to Improve

Authors: Rory Patrick O'Kane

Abstract:

More universities and third level institutions now require at least an IELTS Band 6 for entry into courses of study for non-native speakers of English. This presentation focuses on IELTS Academic Writing Tasks 1 and 2 and in particular on the marking criterion of Coherence and Cohesion. A requirement for candidates aiming at Band 6 and above is that they produce answers which show a clear, overall progression of information and ideas and which use cohesive devices effectively. With this in mind, the presenter will examine what exactly is meant by coherence and cohesion and various strategies which can be used to assist students in improving their scores in this area. A number of classroom teaching ideas will be introduced, and participants will have the opportunity to compare and discuss sample answers written by candidates for this examination with a specific focus on coherence and cohesion. Intended audience: Teachers of IELTS Academic Writing.

Keywords: coherence, cohesion, IELTS, strategies

Procedia PDF Downloads 236
8 A Two Tailed Secretary Problem with Multiple Criteria

Authors: Alaka Padhye, S. P. Kane

Abstract:

The following study considers some variations made to the secretary problem (SP). In a multiple criteria secretary problem (MCSP), the selection of a unit is based on two independent characteristics. The units that appear before an observer are known say N, the best rank of a unit being N. A unit is selected, if it is better with respect to either first or second or both the characteristics. When the number of units is large and due to constraints like time and cost, the observer might want to stop earlier instead of inspecting all the available units. Let the process terminate at r2th unit where r1Keywords: joint distribution, marginal distribution, real ranks, secretary problem, selection criterion, two tailed secretary problem

Procedia PDF Downloads 247
7 Magnetic versus Non-Magnetic Adatoms in Graphene Nanoribbons: Tuning of Spintronic Applications and the Quantum Spin Hall Phase

Authors: Saurabh Basu, Sudin Ganguly

Abstract:

Conductance in graphene nanoribbons (GNR) in presence of magnetic (for example, Iron) and non-magnetic (for example, Gold) adatoms are explored theoretically within a Kane-Mele model for their possible spintronic applications and topologically non-trivial properties. In our work, we have considered the magnetic adatoms to induce a Rashba spin-orbit coupling (RSOC) and an exchange bias field, while the non-magnetic ones induce an RSOC and an intrinsic spin-orbit (SO) coupling. Even though RSOC is present in both, they, however, represent very different physical situations, where the magnetic adatoms do not preserve the time reversal symmetry, while the non-magnetic case does. This has important implications on the topological properties. For example, the non-magnetic adatoms, for moderately strong values of SO, the GNR denotes a quantum spin Hall insulator as evident from a 2e²/h plateau in the longitudinal conductance and presence of distinct conducting edge states with an insulating bulk. Since the edge states are protected by time reversal symmetry, the magnetic adatoms in GNR yield trivial insulators and do not possess any non-trivial topological property. However, they have greater utility than the non-magnetic adatoms from the point of view of spintronic applications. Owing to the broken spatial symmetry induced by the presence of adatoms of either type, all the x, y and z components of the spin-polarized conductance become non-zero (only the y-component survives in pristine Graphene owing to a mirror symmetry present there) and hence become suitable for spintronic applications. However, the values of the spin polarized conductances are at least two orders of magnitude larger in the case of magnetic adatoms than their non-magnetic counterpart, thereby ensuring more efficient spintronic applications. Further the applications are tunable by altering the adatom densities.

Keywords: magnetic and non-magnetic adatoms, quantum spin hall phase, spintronic applications, spin polarized conductance, time reversal symmetry

Procedia PDF Downloads 258
6 Proteomic Evaluation of Sex Differences in the Plasma of Non-human Primates Exposed to Ionizing Radiation for Biomarker Discovery

Authors: Christina Williams, Mehari Weldemariam, Ann M. Farese, Thomas J. MacVittie, Maureen A. Kane

Abstract:

Radiation exposure results in dose-dependent and time-dependent multi-organ damage. Drug development of medical countermeasures (MCM) for radiation-induced injury occurs under the FDA Animal Rule because human efficacy studies are not ethical or feasible. The FDA Animal Rule requires the representation of both sexes and describes several uses for biomarkers in MCM drug development studies. Currently, MCMs are limited and there is no FDA-approved biomarker for any radiation injury. Sex as a variable is essential to identifying biomarkers and developing effective MCMs for acute radiation exposure (ARS) and delayed effects of acute radiation exposure (DEARE). These studies aim to address the death of information on sex differences that have not been determined by studies that included only male, single-sex cohorts. Studies have reported differences in radiosensitivity according to sex. As such, biomarker discovery for radiation-induced damage must consider sex as a variable. This study evaluated the plasma proteomic profile of Rhesus macaque non-human primates after different exposures and doses, as well as time points after radiation. Exposures and doses included total body irradiation between 5-7.5 Gy and partial body irradiation with 5% bone marrow sparing at 9, 9.5 and 10 Gy. Timepoints after irradiation included days 1, 3, 60, and 180, which encompassed both acute radiation syndromes and delayed effects of acute radiation exposure. Bottom-up proteomic analyses of plasma included equal numbers of males and females. In the control animals, few proteomic differences are observed between the sexes. In the irradiated animals, there are a few sex differences, with changes mostly consisting of proteins upregulated in the female animals. Multiple canonical pathways were upregulated in irradiated animals relative to the control animals when subjected to pathway analysis, but differential responses between the sexes are limited. These data provide critical baseline differences according to sex and establish sex differences in non-human primate models relevant to drug development of MCM under the FDA Animal Rule.

Keywords: ionizing radiation, sex differences, plasma proteomics, biomarker discovery

Procedia PDF Downloads 51
5 Enhancing the Aussie Optimism Positive Thinking Skills Program: Short-term Effects on Anxiety and Depression in Youth aged 9-11 Years Old

Authors: Rosanna M. Rooney, Sharinaz Hassan, Maryanne McDevitt, Jacob D. Peckover, Robert T. Kane

Abstract:

Anxiety and depression are the most common mental health problems experienced by Australian children and adolescents. Research into youth mental health points to the importance of considering emotional competence, parental influence on the child’s emotional development, and the fact that cognitions are still developing in childhood when designing and implementing positive psychology interventions. Additionally, research into such interventions has suggested the inclusion of a coaching component aimed at supporting those implementing the intervention enhances the effects of the intervention itself. In light of these findings and given the burden of anxiety and depression in the longer term, it is necessary to enhance the Aussie Optimism Positive Thinking Skills program and evaluate its efficacy in terms of children’s mental health outcomes. It was expected that the enhancement of the emotional and cognitive aspects of the Aussie Optimism Positive Thinking Skills program, the addition of coaching, and the inclusion of a parent manual would lead to significant prevention effects in internalizing problems at post-test, 6- and 18-months after the completion of the intervention. 502 students (9-11 years old) were randomly assigned to the intervention group (n = 347) or control group (n = 155). At each time point (baseline, post-test, 6-month follow-up, and 18-month follow-up), students completed a battery of self-report measures. The ten intervention sessions making up the enhanced Aussie Optimism Positive Thinking Skills program were run weekly. At post-test and 6-month follow-up, the intervention group reported significantly lower depression than the control group, with no group differences at the 18-month follow-up. The intervention group reported significantly lower anxiety than the control group only at the 6-month follow-up, with no group differences in the post-test or at the 18-month follow-up. Results suggest that the enhanced Aussie Optimism Positive Thinking Skills program can reduce depressive and anxious symptoms in the short term and highlight the importance of universally implemented positive psychology interventions.

Keywords: positive psychology, emotional competence, internalizing symptoms, universal implementation

Procedia PDF Downloads 16
4 Clinical Audit on the Introduction of Apremilast into Ireland

Authors: F. O’Dowd, G. Murphy, M. Roche, E. Shudell, F. Keane, M. O’Kane

Abstract:

Intoduction: Apremilast (Otezla®) is an oral phosphodiesterase-4 (PDE4) inhibitor indicated for treatment of adult patients with moderate to severe plaque psoriasis who have contraindications to have failed or intolerant of standard systemic therapy and/or phototherapy; and adult patients with active psoriatic arthritis. Apremilast influences intracellular regulation of inflammatory mediators. Two randomized, placebo-controlled trials evaluating apremilast in 1426 patients with moderate to severe plague psoriasis (ESTEEM 1 and 2) demonstrated that the commonest adverse reactions (AE’s) leading to discontinuation were nausea (1.6%), diarrhoea (1.0%), and headaches (0.8%). The overall proportion of subjects discontinuing due to adverse reactions was 6.1%. At week 16 these trials demonstrated significant more apremilast-treated patients (33.1%) achieved the primary end point PASI-75 than placebo (5.3%). We began prescribing apremilast in July 2015. Aim: To evaluate efficacy and tolerability of apremilast in an Irish teaching hospital psoriasis population. Methods: A proforma documenting clinical evaluation parameters, prior treatment experience and AE’s; was completed prospectively on all patients commenced on apremilast since July 2015 – July 2017. Data was collected at week 0,6,12,24,36 and week 52 with 20/71 patients having passed week 52. Efficacy was assessed using Psoriasis Area and Severity Index (PASI) and Dermatology Life Quality Index (DLQI). AE’s documented included GI effects, infections, changes in weight and mood. Retrospective chart review and telephone review was utilised for missing data. Results: A total of 71 adult subjects (38 male, 33 female; age range 23-57), with moderate to severe psoriasis, were evaluated. Prior treatment: 37/71 (52%) were systemic/biologic/phototherapy naïve; 14/71 (20%) has prior phototherapy alone;20/71 (28%) had previous systemic/biologic exposure; 12/71 (17%) had both psoriasis and psoriatic arthritis. PASI responses: mean baseline PASI was 10.1 and DLQI was 15.Week 6: N=71, n=15 (21%) achieved PASI 75. Week 12: N= 48, n=6 (13%) achieved a PASI 100%; n=16 (34.5%) achieved a PASI 75. Week 24: N=40, n=10 (25%) achieved a PASI 100; n=15 (37.5%) achieved a PASI 75. Week 52: N= 20, n=4 (20%) achieved a PASI 100; n= 16 (80%) achieved a PASI 75. (N= number of pts having passed the time point indicated, n= number of pts (out of N) achieving PASI or DLQI responses at that time). DLQI responses: week 24: N= 40, n=30 (75%) achieved a DLQI score of 0; n=5 (12.5%) achieved a DLQI score of 1; n=1 (2.5%) achieved a DLQI score of 10 (due to lack of efficacy). Adverse Events: The proportion of patients that discontinued treatment due to AE’s was n=7 (9.8%). One patient experienced nausea alleviated by dose reduction; another developed significant dysgeusia for certain foods, both continued therapy. Two patients lost 2-3 kg. Conclusion: Initial Irish patient experience of Apremilast appears comparable to that observed in trials with good efficacy and tolerability.

Keywords: Apremilast, introduction, Ireland, clinical audit

Procedia PDF Downloads 120
3 An Emergentist Defense of Incompatibility between Morally Significant Freedom and Causal Determinism

Authors: Lubos Rojka

Abstract:

The common perception of morally responsible behavior is that it presupposes freedom of choice, and that free decisions and actions are not determined by natural events, but by a person. In other words, the moral agent has the ability and the possibility of doing otherwise when making morally responsible decisions, and natural causal determinism cannot fully account for morally significant freedom. The incompatibility between a person’s morally significant freedom and causal determinism appears to be a natural position. Nevertheless, some of the most influential philosophical theories on moral responsibility are compatibilist or semi-compatibilist, and they exclude the requirement of alternative possibilities, which contradicts the claims of classical incompatibilism. The compatibilists often employ Frankfurt-style thought experiments to prove their theory. The goal of this paper is to examine the role of imaginary Frankfurt-style examples in compatibilist accounts. More specifically, the compatibilist accounts defended by John Martin Fischer and Michael McKenna will be inserted into the broader understanding of a person elaborated by Harry Frankfurt, Robert Kane and Walter Glannon. Deeper analysis reveals that the exclusion of alternative possibilities based on Frankfurt-style examples is problematic and misleading. A more comprehensive account of moral responsibility and morally significant (source) freedom requires higher order complex theories of human will and consciousness, in which rational and self-creative abilities and a real possibility to choose otherwise, at least on some occasions during a lifetime, are necessary. Theoretical moral reasons and their logical relations seem to require a sort of higher-order agent-causal incompatibilism. The ability of theoretical or abstract moral reasoning requires complex (strongly emergent) mental and conscious properties, among which an effective free will, together with first and second-order desires. Such a hierarchical theoretical model unifies reasons-responsiveness, mesh theory and emergentism. It is incompatible with physical causal determinism, because such determinism only allows non-systematic processes that may be hard to predict, but not complex (strongly) emergent systems. An agent’s effective will and conscious reflectivity is the starting point of a morally responsible action, which explains why a decision is 'up to the subject'. A free decision does not always have a complete causal history. This kind of an emergentist source hyper-incompatibilism seems to be the best direction of the search for an adequate explanation of moral responsibility in the traditional (merit-based) sense. Physical causal determinism as a universal theory would exclude morally significant freedom and responsibility in the traditional sense because it would exclude the emergence of and supervenience by the essential complex properties of human consciousness.

Keywords: consciousness, free will, determinism, emergence, moral responsibility

Procedia PDF Downloads 126
2 Temperature Dependence of the Optoelectronic Properties of InAs(Sb)-Based LED Heterostructures

Authors: Antonina Semakova, Karim Mynbaev, Nikolai Bazhenov, Anton Chernyaev, Sergei Kizhaev, Nikolai Stoyanov

Abstract:

At present, heterostructures are used for fabrication of almost all types of optoelectronic devices. Our research focuses on the optoelectronic properties of InAs(Sb) solid solutions that are widely used in fabrication of light emitting diodes (LEDs) operating in middle wavelength infrared range (MWIR). This spectral range (2-6 μm) is relevant for laser diode spectroscopy of gases and molecules, for systems for the detection of explosive substances, medical applications, and for environmental monitoring. The fabrication of MWIR LEDs that operate efficiently at room temperature is mainly hindered by the predominance of non-radiative Auger recombination of charge carriers over the process of radiative recombination, which makes practical application of LEDs difficult. However, non-radiative recombination can be partly suppressed in quantum-well structures. In this regard, studies of such structures are quite topical. In this work, electroluminescence (EL) of LED heterostructures based on InAs(Sb) epitaxial films with the molar fraction of InSb ranging from 0 to 0.09 and multi quantum-well (MQW) structures was studied in the temperature range 4.2-300 K. The growth of the heterostructures was performed by metal-organic chemical vapour deposition on InAs substrates. On top of the active layer, a wide-bandgap InAsSb(Ga,P) barrier was formed. At low temperatures (4.2-100 K) stimulated emission was observed. As the temperature increased, the emission became spontaneous. The transition from stimulated emission to spontaneous one occurred at different temperatures for structures with different InSb contents in the active region. The temperature-dependent carrier lifetime, limited by radiative recombination and the most probable Auger processes (for the materials under consideration, CHHS and CHCC), were calculated within the framework of the Kane model. The effect of various recombination processes on the carrier lifetime was studied, and the dominant role of Auger processes was established. For MQW structures quantization energies for electrons, light and heavy holes were calculated. A characteristic feature of the experimental EL spectra of these structures was the presence of peaks with energy different from that of calculated optical transitions between the first quantization levels for electrons and heavy holes. The obtained results showed strong effect of the specific electronic structure of InAsSb on the energy and intensity of optical transitions in nanostructures based on this material. For the structure with MQWs in the active layer, a very weak temperature dependence of EL peak was observed at high temperatures (>150 K), which makes it attractive for fabricating temperature-resistant gas sensors operating in the middle-infrared range.

Keywords: Electroluminescence, InAsSb, light emitting diode, quantum wells

Procedia PDF Downloads 167
1 Effectiveness of an Intervention to Increase Physics Students' STEM Self-Efficacy: Results of a Quasi-Experimental Study

Authors: Stephanie J. Sedberry, William J. Gerace, Ian D. Beatty, Michael J. Kane

Abstract:

Increasing the number of US university students who attain degrees in STEM and enter the STEM workforce is a national priority. Demographic groups vary in their rates of participation in STEM, and the US produces just 10% of the world’s science and engineering degrees (2014 figures). To address these gaps, we have developed and tested a practical, 30-minute, single-session classroom-based intervention to improve students’ self-efficacy and academic performance in University STEM courses. Self-efficacy is a psychosocial construct that strongly correlates with academic success. Self-efficacy is a construct that is internal and relates to the social, emotional, and psychological aspects of student motivation and performance. A compelling body of research demonstrates that university students’ self-efficacy beliefs are strongly related to their selection of STEM as a major, aspirations for STEM-related careers, and persistence in science. The development of an intervention to increase students’ self-efficacy is motivated by research showing that short, social-psychological interventions in education can lead to large gains in student achievement. Our intervention addresses STEM self-efficacy via two strong, but previously separate, lines of research into attitudinal/affect variables that influence student success. The first is ‘attributional retraining,’ in which students learn to attribute their successes and failures to internal rather than external factors. The second is ‘mindset’ about fixed vs. growable intelligence, in which students learn that the brain remains plastic throughout life and that they can, with conscious effort and attention to thinking skills and strategies, become smarter. Extant interventions for both of these constructs have significantly increased academic performance in the classroom. We developed a 34-item questionnaire (Likert scale) to measure STEM Self-efficacy, Perceived Academic Control, and Growth Mindset in a University STEM context, and validated it with exploratory factor analysis, Rasch analysis, and multi-trait multi-method comparison to coded interviews. Four iterations of our 42-week research protocol were conducted across two academic years (2017-2018) at three different Universities in North Carolina, USA (UNC-G, NC A&T SU, and NCSU) with varied student demographics. We utilized a quasi-experimental prospective multiple-group time series research design with both experimental and control groups, and we are employing linear modeling to estimate the impact of the intervention on Self-Efficacy,wth-Mindset, Perceived Academic Control, and final course grades (performance measure). Preliminary results indicate statistically significant effects of treatment vs. control on Self-Efficacy, Growth-Mindset, Perceived Academic Control. Analyses are ongoing and final results pending. This intervention may have the potential to increase student success in the STEM classroom—and ownership of that success—to continue in a STEM career. Additionally, we have learned a great deal about the complex components and dynamics of self-efficacy, their link to performance, and the ways they can be impacted to improve students’ academic performance.

Keywords: academic performance, affect variables, growth mindset, intervention, perceived academic control, psycho-social variables, self-efficacy, STEM, university classrooms

Procedia PDF Downloads 106