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PubMedDate not supplied

Reflective practice: implementing theory.

Last week, we looked at the theories and models of reflective practice, in a continuing education article. This week, we present a practical example of the introduction, implementation and evaluation of reflection and reflective practice on an acute mental health admission unit. Practitioners used a variety of strategies to increase their awareness of reflective practice, and the author details their analysis and subsequent actions following completion of the project.

Humans↗

PubMedDate not supplied

Implementing reflective practice.

Although nurses understand the need to reflect on their practice, reflection does not occur simply as a result of knowing about it. The author of this literature review seeks to clarify 'reflection' and suggests ways to implement reflective practice.

Ethics, Nursing↗

PubMed1976

Reflective and impulsive children: strategies of information processing underlying differences in problem solving.

The hypothesis that impulsive children differ from reflective children in their preferred strategy of information processing, based on extent of stimulus analysis, was investigated. The experiments employed different age groups and a variety of tasks, including matching, grouping, recall, and concept attainment. Stimuli were presented both visually and auditorily and included both visually and aduitorily and included both verbal and pictorial matrials. The tasks required verbal and nonverbal responses and varied in the level of stimulus analysis necessary for successful performance. The subjects' strategy was assessed by the quality of their performance on tasks requiring detail versus global processing, and by the strategy they chose to adopt in tasks where either detail or global processing led to successful performance. While reflective children performed better on tasks requiring detail analysis than on tasks requiring global analysis, impulsive children showed the reverse trend. Furthermore, when successful solutions could be reached via either a global- or a detail-processing strategy, impulsive children who adopted the former were equally as successful as reflective children who adopted the latter strategy. It was concluded that, contrary to existing views, impulsive children are not inferior to reflective children in general potential or problem-solving ability. Rather, the inferior performance of impulsive children frequently reported in the literature may be due to incompatibility between their preferred global-processing strategy and the detail analysis typically required for successful performance.

Auditory Perception↗

PubMed1998

A critical review of reflective practice in its role towards personal and professional development.

Reflection has become a prominent feature in today's nursing. Love it or hate it, the UK Central Council for Nurses, Midwives and Health Visitors stipulates that evidence of reflective practice is a requirement for both pre and post registration nurses. While reflection can assist in facing the increasing challenges of nursing, it can also present as a challenge in itself unless nurses have familiarised themselves with the process and feel at ease with it. The issues of reflective practice are explored to determine if it can enhance personal and professional development.

Education, Nursing↗

PubMed2000

[Specific aspects of the reflection of signal frequency structure in the peripheral compartment of acoustic analyzer in health state and disease].

How frequency structure of the signals is reflected at the exit of the model of acoustic system peripheral compartment was investigated. The system incorporated mechanisms of local feedback by microphone and overall potentials. Defects in the work of the feedback mechanisms lead to substantial deformation of sound reflection at the model exit. Format structure of the sounds is not reflected. This deteriorates perception. To restore the reflection of the format structure, previous reconstruction is proposed consisting in enhanced degree of contrast of the frequency signal structure.

Acoustics↗

PubMed2001

Spectral reflectance of Picea rubens (Pinaceae) and Abies balsamea (Pinaceae) needles along an elevational gradient, Mt. Moosilauke, New Hampshire, USA.

Relationships among elevation, foliar morphology, spectral reflectance, and chlorophyll fluorescence of two co-occurring montane conifers, red spruce (Picea rubens Sarg.) and balsam fir (Abies balsamea [L.] Mill.), were investigated along two transects from 460 to 1460 m on Mt. Moosilauke in the White Mountains of New Hampshire, USA. Spectral reflectance (300-1100 nm wavelengths) and the chlorophyll fluorescence F(v)/F(m) ratio were measured on dark-adapted needles. Foliar morphology (needle size, shape, and mass) and nitrogen concentrations were measured in the laboratory. Reflectance spectra varied between species and with elevation. Two chlorophyll measures, red edge position and a chlorophyll-based difference index (Chl NDI = R750 - R705/R750 + R705), indicated more chlorophyll in fir than in spruce and decreasing chlorophyll with increasing elevation in both species. The structure-independent pigment index (SIPI = R800 - R445/R800 - R680) increased with elevation, indicating an increasing carotenoid : chlorophyll ratio. The photochemical reflectance index (PRI = R531 - R570/R531 + R570), a measure of photosynthetic radiation use efficiency, decreased with increasing elevation up to 1370 m. In the highest elevation site, within the stunted alpine krummholz at 1460 m, PRI was higher than at 1370 m, but still lower than at 1070 m. This same pattern was evident in the chlorophyll fluorescence F(v)/F(m) measurements. These independent indices indicate higher stress in spruce than fir, which may be related to the "spruce decline" reported in the northeastern USA. Results also indicate progressively increasing stress with increasing elevation up to 1370 m. Stress appears to be lower at 1460 m than at 1370 m, despite the harsher conditions at the very summit of Mt. Moosilauke. This may be a consequence of stress-tolerant physiology and/or prostrate architecture.

Journal Article↗

PubMed2002

Multi-wavelength reflectance pulse oximetry.

The performance of current reflectance pulse oximeters is hindered by poor signal-to-noise ratio. To overcome this problem a new reflectance oximeter has been developed with a sensor which consists of three LEDs and two continuous photodetector rings placed equidistant from the center of the LEDs. In addition, ultra low noise electronics and adaptive algorithm assure improved performance. A validation study was performed on 10 healthy volunteers. Sensors were placed on several sites and measurements were compared to reference arterial blood samples. During the study progressive hypoxemia was induced by lowering the inspired oxygen concentration (FiO2) to 10%, followed by a recovery phase. Twelve blood samples were taken during each cycle, yielding a total of 120 measured data points. Data from randomly selected 5 subjects was used for calibration and subsequently tested on the other 5 subjects. Results proved to be well within clinically acceptable boundaries for all 3 sampling sites with high correlation (R2 > 0.9) and SD around 2%. In conclusion, a new 3 wavelength reflectance pulse oximeter with unique sensor geometry and improved algorithms provides enhanced performance and is less susceptible to poor signal to noise conditions when compared to existing reflectance oximetry systems.

Adult↗

PubMedDate not supplied

The establishment of a nurse consultant role in paediatric intensive care: a reflective analysis.

Through a review of literature and research, together with reflection on clinical practice, this article reflectively analyses and evaluates the concept of the establishment and development of a nurse consultant post in paediatric intensive care. Manley's (1997) conceptual framework is used as a structure for the reflection, which has enabled a detailed and logical approach and allowed both reflection and analysis of the role in relation to the speciality. It is evident that nurse consultant posts have been developed in a variety of clinical specialities and are providing a real opportunity to improve patient care, progress nursing as a profession and provide a clinical career framework for nurses. The concept of the nurse consultant in paediatric intensive care is both innovative and strategic: Manley has identified many sub-roles, skills and processes necessary to influence and develop the role. The elements of 'transformational leadership', 'change agent' and 'collaborator' identified by Manley appear to hold the key to the ability to influence and develop paediatric intensive care nursing from a practice perspective.

Clinical Competence↗

PubMed2000

[A reflection interference method for determining optical constants and thickness of a thin solid film].

In this paper we report a simple method for deducing optical constants and thickness from the reflection interference spectrum of a thin transparent film which is on a substrate of high reflection coefficient. When a light beam is incident on the surface of the film, the reflection light beams at the front and rear faces are coherent. We calculated the optical constants and thickness of the film from the reflection spectrum. This simple method makes a directly programmable calculation possible.

English Abstract↗

PubMed2003

Reflective learning in community-based dental education.

Learners gain additional value from community-based education when they are guided through a reflective process. The purpose of this article is to describe how structured reflection assignments and methods are incorporated in the University of North Carolina School of Dentistry's community-based DISC (Dentistry in Service to Communities) program. The following strategies are described as ways to enrich community-based learning experiences for dental students: photographic documentation; written narratives; critical incident reports; and mentored post-experiential small group discussions. Fieldwork and course-related examples are drawn from community-based dental experiences to illustrate how reflective teaching approaches can enhance student learning. A directed process of reflection is suggested as a way to increase the impact of the community learning experience.

Attitude of Health Personnel↗

PubMed2003

[Ethics in clinical research: contextualizing and reductionist problem definitions, forms of ethical reflection and some particular implications].

The present paper starts off with a short outline of issues, conflicts, and goals of ethical reflection about clinical research. It is then argued that non-reductionist, patient-centred ethics should critically reflect on medically preformed problem definitions, ways of problem solution, and evaluations. The shortcomings of such preformed perceptions and interpretations are illustrated using the examples of dementia research, and the complexities of the notion of risk. A more comprehensive approach including the perceptions, interpretations, and evaluations of the patients' perspective necessitates a form of ethical reflection which takes into account the social and cultural contexts of clinical research, and which therefore relies on concepts and methods of the cultural sciences (in particular history, sociology, and cultural anthropology). The decision for a reductionist, or for a contextualising mode of ethical reflection represents in itself a value decision and needs to be explicitly justified.

Clinical Trials as Topic↗

PubMed1997

[The study of interactions of [CpFe(Co)2]2 with surface of alumina and Titania supports by Fourier transform diffuse reflection and photoacoustic infrared spectroscopy].

The diffuse reflection and photoacoustic infrared spectra of the species derived from dicarbonyl (eta5-cyclopentadienyl)iron (0) {[CpFe(CO)2]2 (Cp = eta5-C5H5)} which are supported on the surfaces of acidic,neutral and basic alumina (Al2O3) and Titania (TiO2) have been measured. The structures, stabilities and concentrations of these supported organometallic species depend markedly on the acid-base properties of the alumina surfaces. There is mainly species of [CpFe(CO)2Fe-H-Fe(CO)2Cp]+ on the surface of [CpFe (CO)2]2/Al2O3 (acidic) (A). The species of CpFe(CO)2(-O-) and [CpFe(CO)]4 are observed on the surface of [CpFe(CO)2]2/Al2O3(neutral)(B). On the suface of [CpFe(CO)2]2/Al2O3 (basic) (C), the mainly species is [CpFe(CO)2]4 with a few CpFe(CO)2(-O-) species. The concentration of species is highest on the surface of A and lowest on the, surface of C. The diffuse reflection and photoacoustic (middle and near )infrared spectra of [CpFe(CO)2]2/TiO2(T) show that the [CpFe(CO)2]2 absorbed on the surface of TiO2 is stable in the air at the room temperature. There is no a species derived from [CpFe(CO)2]2 to be observed. The diffuse reflection near infrared spectra of [CpFe(CO)2]2(D) and [CpFe(CO)2]2/TiO2 (T) are measured. Most of them are assigned to overtone and combination of carbonyl vibrations and several peaks are assigned to triple overtone and triple combination. The diffuse reflection infrared spectroscopy is the good method to study the interaction of organometallic compounds with metal oxide powder.

English Abstract↗

PubMed1992

Quantitative genetic analysis of skin reflectance: a multivariate approach.

Skin color is a polygenically determined quantitative trait. Although it has been used extensively in studies of between-population variation, there have been relatively few studies of the inheritance of skin color. In this article we use measurements on 359 members of the Jirel population of eastern Nepal to assess the heritabilities and additive genetic correlations of three skin reflectance measures. Skin color was measured at the upper inner arm site at three wavelengths. A maximum likelihood approach was used to estimate sex and age effects on skin reflectance, heritabilities, and phenotypic variances at each wavelength and both additive genetic and environmental correlations between wavelengths. This technique incorporated information from 36 pedigrees with 2-25 members and 173 independent individuals. Likelihood ratio tests were used to assess the significance of specific variance/covariance components. The results indicate that skin reflectances are moderately heritable at all three wavelengths. The pairwise phenotypic correlations ranged from 0.76 to 0.88. The observed additive genetic correlations were not significantly different from 1.00, suggesting that the same loci influence variation at each wavelength. This evidence for relatively complete pleiotropy implies that measurements at multiple wavelengths yield little additional genetic information, although they may be useful for reducing measurement error. Based on estimates of the genetic and phenotypic covariance matrices, we determined that skin reflectance measurements are expected to provide only as much information for assessing local between-population genetic variation as a single two-allele polymorphic marker. Therefore microevolutionary studies based on skin color variation should be viewed with caution.

Adolescent↗

PubMed2005

[Analysis of reflective IR transmittance spectra at oblique incidence of micrometer SiO2 films on c-Si substrate].

The reflective infrared transmittance spectra at oblique incidence of SiO2 films deposited on c-Si wafer have been measured. The thickness of the films was micrometer quantity. The spectra showed many differences from the common transmittance (or absorption) spectra in the range of 900-1 250 cm(-1). The reflectivity peak at 1100 cm(-1) was found and its position was essentially fixed. With the thickness increased, the drop of peak at 1100 cm(-1) and hollow at 1200 cm(-1) became gradually slow. As the thickness increased to be over 2 micrometers, the shape of the spectra in 1075-1250 cm(-1) did not change obviously. The analysis showed that the measured spectrum was composed of reflectivity spectrum and absorption spectrum of the SiO2 film, which occurred at Air/SiO2 interface and SiQ2 layer respectively. When the thickness was over one micrometer and the film had considerable absorption, the contribution from reflectivity spectrum became very obvious. So the absorption is not the only factor in the analysis of these spectra.

Absorption↗

PubMed2006

[The reflection spectrometer and quantitative analysis design].

The reflection spectrometer with optical fibre transmission was designed and used in quantitative analysis. The reflection spectrometry was applied to the determination of reducing sugar in samples based on the reduction reaction of the reducing sugar with Fehling's reagent. The reduction reaction was carried out in a micro-reaction cell, and the reddish colored Cu2O produced was settled at the bottom of the reaction cell. The reflectance R(infinity), which is directly proportional to the amount of Cu2O produced, was measured by the reflection spectrometer. The fundamental principle, effect factors, and experimental conditions of the method were discussed. Linear relationship was obtained in the range of 20-120 microg of reducing sugar. The special features of this method were its simplicity in operation, relatively high sensitivity of determination, and the use of small amount of reagent. Satisfactory results were obtained in its application to the analysis of wine and honey samples.

English Abstract↗

PubMed1991

Reflection of CO2 laser radiation from laser-resistant endotracheal tubes.

To assess the possibility of indirect damage by CO2 laser reflection from specialized or modified tracheal tubes, four different tracheal tubes were studied. They were (1) a Rusch red rubber tracheal tube wrapped with 3M No. 425 aluminum foil tape, (2) a Rusch red rubber tracheal tube wrapped with Venture copper foil tape, (3) a polyvinylchloride tracheal tube wrapped with Laser-Guard protective coating, and (4) a Mallinckrodt Laser-Flex tracheal tube. The tracheal tubes were straightened and centered within cardboard cylinders and the laser set to 40 W was aimed to reflect from the tracheal tubes onto the cardboard. The times to combustion perforating the cardboard cylinders because of laser reflection were 1.41 +/- 0.54 (mean +/- SD), 1.73 +/- 0.93, 3.70 +/- 2.18, and 9.26 +/- 3.40 s for tracheal tubes 1, 2, 3, and 4, respectively. The differences between the times to combustion with tracheal tubes 3 and 1, 3 and 2, 4 and 1, 4 and 2, and finally, 4 and 3 were statistically significant. We conclude that the Laser-Guard-wrapped polyvinylchloride tracheal tube and the Mallinckrodt Laser-Flex tracheal tube were less reflective of incident CO2 laser radiation than the copper or aluminum-foil-wrapped red rubber tracheal tubes.

Carbon Dioxide↗

PubMed1990

Evaluation of the depth sensitivity of tissue reflectance spectrophotometry in gingival measurement.

Tissue reflectance spectrophotometry (TRS) can estimate hemoglobin concentration (Hb index) and oxygen saturation of hemoglobin (apparent SO2) in tissues. Reflectance spectra were measured in a gingiva-model and in human gingival biopsies by TRS. The gingiva-model was composed of human red cells and white gel in a cuvette placed on a black or white surface. The distance from the bottom surface of the cuvette to the optical probe was decreased from 5.0 to 0.5 mm. The Hb index in the gingiva-model on the black surface was constant before decreasing at less than a 3.0 mm distance. However, the Hb index in the gingiva-model on the white surface showed a decrease at less than a 1.5 mm distance. Apparent SO2 was constant at more than a 1.0 mm distance. Reflectance spectra were measured from human gingival tissue preparations, by slicing them off with microtome and making them less thick each time. Changes in reflectance spectra were observed in less than 1.0-1.5 mm thick specimens. These results suggest that the sensitivity in TRS measurement may exist within 1.0-1.5 mm from the gingival surface, and the limit of depth at which the TRS can measure may be within 3.0 mm.

Gingiva↗

PubMedDate not supplied

A comparison of a new reflectance oximeter with the Hewlett-Packard ear oximeter.

The purpose of this study was to characterize the accuracy and dynamic response characteristics of traditional transmittance pulse oximeters and a new reflectance pulse oximeter with regard to the current standard in oximetry, the Hewlett-Packard ear oximeter. Studies were performed with 15 healthy male and female subjects. A rebreathing technique was employed to produce a steady fall in oxygen saturation and to maintain constant, eucapnic, end-tidal CO2 levels. The oximeters' analog outputs were recorded by a Western Graphtec Linearecorder and by an IBM-PC utilizing an analog-to-digital converter for data collection at 5 Hz. The agreement between two clinical methods of measurement was used as the statistical technique of comparing new technology (pulse oximetry) with the current standard (Hewlett-Packard ear oximetry). The mean of the difference between the Hewlett-Packard and the pulse oximeter with reflectance sensor was 0.28%, with a range of difference of +/- 3.49%. This value was similar to that of the transmittance oximeters (Criticare 501+: 0.92 +/- 2.11), (Physio-Control: 3.15 +/- 2.04), (Ohmeda 3700: 2.05 +/- 2.06). There was virtually no response-time difference between the reflectance oximeter with the sensor placed on the subject's forehead and the Hewlett-Packard ear oximeter. The authors conclude that the accuracy of the reflectance oximeter is within the limits of clinical acceptance for monitoring and trending of arterial oxygen saturation in healthy subjects.

Equipment Design↗