911 resultados para Wilderness Room (Drama)
Resumo:
Microelectrode voltammetry is used to study the electrochemical reduction of dioxygen, O-2, in the room-temperature ionic liquid trihexyl(tetradecyl)phosphonium trifluorotris(pentafluoroethyl)phosphate [P6,6,6,14][FAP]. The nature of the unusual voltammetric waves is quantitatively modeled via digital simulation with the aim of clarifying apparent inconsistencies in the literature. The reduction is shown to proceed via a two-electron reaction and involve the likely capture of a proton from the solvent system. The oxidative voltammetric signals seen at fast scan rates are interpreted as resulting from the reoxidation of HO2 center dot. In the presence of large amounts of dissolved carbon dioxide the reductive currents decrease by a factor of ca. two, consistent with the trapping of the superoxide radical, O-2(center dot), intermediate in the two-electron reduction process.
Resumo:
The voltammetry for the reduction of 2-nitrotoluene at a gold microdisk electrode is reported in two ionic liquids: trihexyltetradecylphosphonium tris(pentafluoroethyl)trifluorophosphate ([P-14,P-6,P-6,P-6][FAP]) and 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Emim][NTf2]). The reduction of nitrocyclopentane (NCP) and 1-nitrobutane (BuN) was investigated using voltammetry at a gold microdisk electrode in the ionic liquid [P-14,P-6,P-6,P-6][FAP]. Simulated voltammograms, generated through the use of ButlerVolmer theory and symmetric MarcusHush theory, were compared to experimental data, with both theories parametrizing the data similarly well. An experimental value for the Marcusian parameter, 1 was also determined in all cases. For the reduction of 2-nitrotoluene, this was 0.5 +/- 0.1 eV in both solvents, while for NCP and BuN in [P-14,P-6,P-6,P-6][FAP], it was 2 +/- 0.1 and 5 +/- 0.1 eV, respectively. This is attributed to the localization of charge on the nitro group and the primary nitro alkyls increased interaction with the environment, resulting in a larger reorganization energy.
Resumo:
Asymmetric MarcusHush (AMH) theory is applied for the first time in ionic solvents to model the voltammetric reduction of oxygen in 1-butyl-1-methylpyrrolidinium bis-(trifluoromethylsulfonyl)-imide and of 2-nitrotoluene (2-NT), nitrocyclopentane (NCP), and 1-nitro-butane (BuN) in trihexyltetradecylphosphonium tris(pentafluoroethyl)trifluorophosphate on a gold microdisc electrode. An asymmetry parameter, gamma, was estimated for all systems as -0.4 for the reduction of oxygen and -0.05, 0.25, and 0 +/- 0.05 for the reductions of 2-NT, NCP, and BuN, respectively, which suggests equal force constants of reactants and products in the case of 2-NT and BuN and unequal force constants for oxygen and NCP where the force constants of the oxidized species are greater than the reduced species in the case of oxygen and less than the reduced species in the case of NCP. Previously measured values for a, the Butler-Volmer transfer coefficient, reflect this in each case. Where appreciable asymmetry occurs, AMH theory was seen to parametrize the experimental data better than either Butler-Volmer or symmetric Marcus-Hush theory, allowing additionally the extraction of reorganization energy. This is the first study to provide key physical insights into electrochemical systems in room-temperature ionic liquids using AMH theory, allowing elucidation of the reorganization energies and the relative force constants of the reactants and products in each reaction.
Resumo:
The teaching and cultivation of professionalism is an integral part of medical education as professionalism is central to maintaining the public’s trust in the medical profession. Traditionally professional values would have been acquired through an informal process of socialisation and observation of role models. Recently, however, medical educators have accepted the responsibility to explicitly teach and effectively evaluate professionalism. A comprehensive working definition of the term professionalism and a universally agreed list of the constituent elements of professionalism are currently debated. The School of Medicine and Dentistry of The Queen’s University of Belfast uses an approach of self-directed learning for teaching anatomy, and students are given the opportunity to learn anatomy from human dissection. Self-directed learning teams have been found to be underutilised as educational strategies and presented an opportunity to utilise the first year dissection room teaching environment to nurture the development of the attributes of professionalism. An educational strategy based on role-playing was developed to engage all students around the dissection table. Students received comprehensive background reviews on professionalism, its attributes and the identification of such attributes in the context of the dissection room. Roles, with specific duties attached, were allocated to each team member. Circulating academic staff members directly observed student participation and gave formative feedback. Students were given the opportunity to reflect on their ability to identify the attributes and reflect on their own and their peer’s ability to develop and practise these attributes. This strategy indicated that small group learning teams in the dissection room utilise widely accepted principles of adult learning and offer an opportunity to create learning activities that will instil in students the knowledge, values, attitudes and behaviours that characterise medical professionalism. Anatomy faculty have a responsibility to nurture and exemplify professionalism and play a significant role in the early promotion and inculcation of professionalism. It remains imperative not only to assess this strategy but also to create opportunities for critical reflection and evaluation within the strategy. Key words: Medical Education – Professionalism – Anatomy - Reflective Practise – Role-play
Resumo:
Background: Men continue to smoke in greater numbers than women; however, few interventions have been developed and tested to support men’s cessation. Men also tend to rely on quitting strategies associated with stereotypical manliness, such as willpower, stoicism and independence, but may lack the self‐efficacy skills required to sustain a quit. In this article we describe the development of and reception to an interactive video drama (IVD) series, composed of 7 brief scenarios, to support and strengthen men’s smoking cessation efforts. The value of IVD in health promotion is predicated on the evidence that viewers engage with the material when they are presented characters with whom they can personally identify. The video dramatizes the challenges unfolding in the life of the main character, Nick, on the first day of his quit and models the skills necessary to embark upon a sustainable quit.
Objective: The objective was to describe men’s responses to the If I were Nick IVD series as part of a pilot study of QuitNow MenTM, an innovative smoking cessation website designed for men. Specific objectives were to explore the resonance of the main character of the IVD series with end‐users, and men’s perceptions of the effectiveness of the IVD series for supporting their quit self‐management.
Methods: Seven brief IVD scenarios were developed, filmed with a professional actor and uploaded to a new online smoking cessation website, QuitNow MenTM. A sample of 117 men who smoked were recruited into the study and provided baseline data prior to access to the QuitNow MenTM website for a 6 month period. During this time, 47 men chose to view the IVDs. Their responses to questions about the IVDs were collected in 3‐month and 6‐month online follow‐up surveys and analyzed using descriptive statistics.
Findings: The majority of participants indicated they related to the main character, Nick. Participants who “strongly agreed” they could relate to Nick perceived significantly higher levels of support from the IVDs than the “neutral” and “disagree” groups (P <.001, d =2.0, P <.001 d =3.1). The “agree” and “neutral” groups were significantly higher on rated support from the videos than the “disagree” (P <.001 d =2.2, P =.01 d = 1.5). Participants’ perception of the main character was independent of participant age, education attainment or previous quit attempts.
Conclusions: The findings suggest that IVD interventions may be an important addition to men’s smoking cessation programs. Given that the use of IVD scenarios in health promotion is in its infancy, the positive outcomes from this pilot study signal the potential for IVD and warrant ongoing evaluation in smoking cessation and, more generally, men’s health promotion.
Resumo:
The low cycle fatigue (LCF) properties and the fracture behavior of China Low Activation Martensitic (CLAM) steel have been studied over a range of total strain amplitudes from 0.2 to 2.0%. The specimens were cycled using tension-compression loading under total strain amplitude control. The CLAM steel displayed initial hardening followed by continuous softening to failure at room temperature in air. The relationship between strain and fatigue life was predicted using the parameters obtained from fatigue test. The factors effecting on low cycle fatigue of CLAM steel consisted of initial state of matrix dislocation arrangement, magnitude of cyclic stress, magnitude of total strain amplitude and microstructure. The potential mechanisms controlling the stress response, cyclic strain resistance and low cycle fatigue life have been evaluated.
Resumo:
A range of liquid rare-earth chlorometallate complexes with alkyl-phosphonium cations, [P666 14]+, has been synthesised and characterised. EXAFS confirmed the predominant liquid-state speciation of the [LnCl6]3- of the series with Ln = Nd, Eu, Dy. The crystal structure of the shorter-alkyl-chain cation analogue [P4444]+ has been determined and exhibits a very large unit cell. The luminescence properties, with visible light emissions of the liquid Tb, Eu, Pr and Sm and the NIR emissions for the Nd and Er compounds were determined. The effective magnetic moments were measured and fitted for the Nd, Tb, Ho, Dy, Gd and Er samples.
Resumo:
PURPOSE: To clarify the risk parameters measured by anterior segment optical coherence tomography (AS-OCT) for elevated intraocular pressures (IOP) provoked by the darkroom test and to provide recommendations for its clinical usage. METHODS: Subjects aged >40 years and whose peripheral anterior chambers were ≤1/4 corneal thickness were recruited. The anterior segment of the eye was imaged in sitting position and under both light and dark conditions and biometry was performed using anterior segment optical coherence tomography. The analyzed parameters were: (1) central anterior chamber depth (ACD); (2) anterior chamber width; (3) pupil diameter; (4) iris curvature; (5) lens thickness; and (6) number of meridians with closed angles (NCA). Then the darkroom test was performed and a positive provocative test result was defined as a rise in IOP ≥8 mm Hg after the test. Statistical analyses included: (1) the difference in parameters between positive and negative eyes; (2) the association between posttest IOP and the parameters; and (3) the difference in parameters between the 2 eyes in subjects with the asymmetric results. RESULTS: A total of 70 subjects were recruited. ACD (P=0.022), NCA in light (P<0.001), and NCA in dark (P<0.001) were different significantly between eyes with positive and negative results. There was a strong association between NCA in dark (r=0.755, P<0.001) and the posttest IOP. Among subjects with asymmetric results between the 2 eyes, the ACD was shallower and the lens thickness was larger in the positive eye. CONCLUSIONS: The posttest IOP is determined by the extent of functionally closed angles in the dark. The test may be useful in the early diagnosis of primary angle closure. At the same time, angle configuration should be evaluated to remove false positive result.
Resumo:
BACKGROUND: Primary angle-closure glaucoma (PACG) is a major cause of visual morbidity in East Asia. Dark-room provocative test (DRPT) has been used to determine which narrow angles have the risk to develop angle closure. However, the accuracy of DRPT might be altered because that after emerging from the dark room, the configuration of the angle is affected by the light of the slit-lamp and the appositionally closed angle reopens. The aim of this study was to examine the pupillary diameter in different light conditions and use it as a parameter to assess the accuracy of dark-room provocative test. METHODS: Patients with suspected primary angle-closure glaucoma undergoing DRPT were recruited. The anterior chamber angle was examined by anterior segment optical coherence tomography under the following conditions: (1) in standard room illumination; (2) after short-term dark-adaptation and (3) after DRPT. Mean values of pupil size and numbers of appositionally closed angle under different conditions were compared. RESULTS: A total of 47 eyes of 47 patients were analyzed. The pupil size after DRPT was smaller than that after short-term dark-adaptation (P < 0.001) and smaller than that in standard room illumination (P = 0.026). The numbers of appositionally closed angles after short-term dark-adaptation were significantly larger than those after DRPT (P < 0.001). There was no significant difference between the numbers of appositionally closed angles in standard room illumination and after DRPT (P = 0.157). CONCLUSIONS: Constriction of pupil size immediately after prolonged dark room provocative test may lead to change in the angle configuration, which may lead to false negative results. We suggest a modified protocol of recording intraocular pressure immediately after DRPT and performing gonioscopy following short-term dark adaptation to improve the accuracy of angle closure assessment.
Resumo:
The high temperature magnetic and structural properties of an amphiphilic iron(III) spin crossover complex are reported. Thermal cycling reveals a scan rate-dependent 20 K thermal hysteresis in the mT vs. T data close to room temperature. A fast scan rate is essential for the hysteresis but it is robust and reproducible after multiple thermal cycles. Differential scanning calorimetry and cross polarized microscopy are used to show that the magnetic switching aligns with a material state change from solid to ordered liquid phase on warming.
Resumo:
Ultrasound absorption spectra of four 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide were determined as a function of the alkyl chain length on the cation from 1-propyl- to 1-hexyl- from 293.15 to 323.15 K at ambient pressure. Herein, the ultrasound absorption measurements were carried out using a standard pulse technique within a frequency range from 10 to 300 MHz. Additionally the speed of sound, density and viscosity have been measured. The presence of strong dissipative processes during the ultrasound wave propagation was found experimentally, i.e. relaxation processes in the megahertz range were observed for all compounds over the whole temperature range. The relaxation spectra (both relaxation amplitude and relaxation frequency) were shown to be dependent on the alkyl side chain length of the 1-alkyl-3-methylimidazolium ring. In most cases, a single Debye model described the absorption spectra very well. However, a comparison of the determined spectra with the spectra of a few other imidazolium-based ionic liquids reported in the literature (in part recalculated in this work) shows that the complexity of the spectra increases rapidly with the elongation of the alkyl chain length on the cation. This complexity indicates that both the volume viscosity and the shear viscosity are involved in relaxation processes even in relatively low frequency ranges. As a consequence, the sound velocity dispersion is present at relatively low megahertz frequencies.
Resumo:
This paper investigates the environmental conditions inside a highly-glazed cross-ventilated meeting room. A 3D computational fluid dynamics (CFD) model of an indoor environment is developed with the support of the field measurements performed in a normally operating room. The work presented here follows the steps of the formal calibration methodology for the development of CFD models of naturally ventilated environments. This paper utilises the calibration methodology in order to predict environmental conditions within the highly-glazed cross-ventilated room occupied by people. The CFD model is verified and validated with field measurements performed in an operating building. Moreover, parametric analysis determines the most influential boundary conditions on indoor air temperatures and air speeds