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PubMedDate not supplied

Reflective practice: a meaningful task for students.

AIMS: To ascertain whether students found reflection to be a meaningful activity, whether there are perceived benefits associated with reflective practice and whether it is a valid process on which to assess the outcomes of a course relating to the competencies of specialist practice. METHOD: The attitudes of students attending a one-year degree course were examined using a focus group interview and a web discussion board. The evaluation of the focus group interviews and web-based discussion postings are discussed. FINDINGS: Reflective writing is considered a key component of portfolio assessment because it provides evidence of skills development and increasing clinical competence. There was no consensus on whether or not reflection is a meaningful activity. The students' learning style is pertinent to their perception of the usefulness of reflection. CONCLUSION: The findings indicated the scepticism with which some students approached the task, but they also identified that reflection had a positive impact on the practice of students more able to embrace the process in a meaningful way. There is scope to extend this work to examine the use of reflection in developing the growing body of practice knowledge that underpins nursing.

Creativity↗

PubMed1992

The directional reflectance of the retinal nerve fiber layer of the toad.

Various optical methods for assessing the retinal nerve fiber layer (RNFL) depend on reflected light, but little is known about the characteristics of the RNFL as a reflecting structure. The authors investigated the angular dependence of light reflected by the unmyelinated nerve fibers of the toad eyecup using a small 500-nm light source that could illuminate the retina from various directions and a movable low-power microscope that imaged the retina onto a cooled charge-coupled device in a digital camera system. Measured areas had nerve fiber bundles separated by gaps. Therefore, the reflectance of a bundle alone could be determined from the difference in intensity between the bundle and an adjacent gap. The RNFL reflectance showed striking directional dependence; nerve fiber bundles seen when illuminated from one direction disappeared completely when illuminated from another. Light reflected by a bundle was confined to a conical sheet concentric with the axis of the bundle. The apex angle of the cone was twice the angle between the incident light and the bundle axis, and the orientation of the cone changed with the orientation of the RNFL. This behavior was consistent with the theory of light scattering by cylinders. Therefore, it was concluded that the RNFL reflectance arises from cylindric structures. These results have clinical significance for imaging the RNFL in the human eye because the apparent intensity of the RNFL will depend, not just on its thickness, but also on its orientation relative to the imaging system.

Animals↗

PubMed2006

[Quantitative relationships between leaf area index and canopy reflectance spectra of wheat].

Based on the change patterns of leaf area index (LAI) and canopy spectral reflectance of wheat at different growth stages and nitrogen application rates, this paper investigated the relationships of LAI with canopy reflectance and spectral parameters, and brought forward the sensitive spectral parameters and quantitative equation for predicting wheat LAI. The results showed that with increasing nitrogen application rate, wheat LAI and its canopy reflectance at near infrared (760 to approximately 1220 nm) increased, whereas the reflectance at visible band (460 to approximately 710 nm) decreased. From jointing to maturity, the LAI and the reflectance of short bands in near infrared increased initially and decreased then, whereas the reflectance of visible light and long bands in near infrared was in adverse, with the lowest value appeared at booting stage. Wheat LAI was negatively correlated with the reflectance of visible light, but positively with that of short bands in near infrared, with the highest correlation coefficient at 810 nm. It was proposed that wheat LAI could be well monitored by vegetation indices RVI (810, 510) and DVI (810, 560). PVI and TSAVI were proved to be the spectral indices in monitoring wheat LAI, and higher accuracy was obtained with combined RVI (810, 510), DVI (810, 560) and PVI.

Ecosystem↗

PubMedDate not supplied

[An analysis of isometric reflections in morphology exemplified by the mandible of the rat (Rattus, Rodentia)].

Individual, age, sex, and species differences of morphological shape is treated as a result of general shape formation process. It is assumed that mutual reflections of these differences could be described by continuous and discontinuous transformations. The first type of these reflects equilibrium properties of shape formation, while the second type reflects its non-equilibrium properties. Equilibrium process is strongly canalized and is able to generate quite limited diversity of shapes. Contrary to this, non-equilibrium process can generate a lot of different shapes, as it destroys canalized relations between characters. Idea of equilibrium process provides a background for formulation of null hypothesis about anticipated relations between characters. Statistically significant deviations from these relations allow to recognize characters that mark areas of possibly non-equilibrium transformations. Analysis of localizations of all such characters allows to formulate more meaningful hypothesis about shape transformations for a particular morphological object. Some easily available statistical methods of recognizing characters that reflect either continuous of discontinuous transformations are exposed using mandible of three rat species as an example. It is shown that discontinuous transformations are located mainly in the same areas of mandible in all modes of inter-reflections. Characters (linear measurements between morphometric landmarks) with continuous inter-reflections describe transformations of general shape of the mandible. Characters with discontinuous inter-reflections mark boundaries between functional blocks and areas with the heaviest dynamic loads.

Aging↗

PubMedDate not supplied

Clinical utility of a glucose reflectance meter for screening neonates for hypoglycemia.

OBJECTIVE: The purpose of this study was to examine the clinical utility of a glucose reflectance meter to screen neonates for hypoglycemia. STUDY DESIGN: One hundred six infants admitted to the observation or level III nursery with a screening whole blood glucose concentration < or = 2.8 mmol/L (< or = 50 mg/dl) had a second sample drawn to compare glucose reflectance meter measurements with those of corrected laboratory-determined glucose concentrations. Error grid analysis was used to determine clinical utility of the reflectance meter in a clinical setting. RESULTS: No reading obtained with the glucose reflectance meter was > 2.2 mmol/L (40 mg/dl) in infants whose true whole blood glucose concentration was < or = 1.7 mmol/L (30 mg/dl). Only 0.9% (1/106) of glucose reflectance meter values were < or = 1.7 (< or = 30 mg/dl) when the simultaneous laboratory-determined whole-blood glucose concentration was > 2.2 mmol/L (40 mg/dl). Glucose concentrations obtained by the reflectance meter correlated (r = 0.77, p = 0.001) with laboratory-determined concentrations. CONCLUSION: The glucose reflectance meter provides a rapid and clinically useful method of screening for neonatal hypoglycemia.

Blood Chemical Analysis↗

PubMed1998

Comparison of skin reflectances between Bolivian lowlanders and highlanders of European ancestry.

I compared one genetic marker, skin reflectances, between Bolivians of European ancestry residing at high altitude in La Paz (3600 m; 41 boys and 65 girls) and at low altitude in Santa Cruz (400 m; 140 boys and 117 girls). Reflectances were measured at three wavelengths (425 nm, 545 nm, and 685 nm) on two different sites: the medial surface of the inner upper arm and the forehead. Principal components analysis was used to reduce age-, sex-, and surname-standardized reflectances to three independent components. The first principal component, which assesses the genetic component of melanin concentration, did not differ between samples, indicating that there are no significant differences between lowland and highland Bolivians of European ancestry with respect to the genetic component of skin reflectances. The second principal component, which assesses the influence of tanning on skin reflectance, also did not differ significantly between highlanders and lowlanders. Finally, the third principal component, which assesses the impact of vascularity on skin reflectance, was significantly lower in residents of La Paz than in residents of Santa Cruz, suggesting a greater vascularity-induced darkening of skin color in highlanders than lowlanders, possibly reflecting the higher hemoglobin concentrations that are typical of highland populations.

Acclimatization↗

PubMed2000

Assessment of retinal nerve fiber layer internal reflectivity in eyes with and without glaucoma using optical coherence tomography.

OBJECTIVE: To assess the internal reflectivity of the retinal nerve fiber layer in normal, ocular hypertensive, and glaucomatous eyes using optical coherence tomography. METHODS: All patients underwent complete ophthalmic examination and achromatic automated perimetry. Intraocular pressure was 21 mm Hg or less for low-tension glaucoma and normal eyes and at least 25 mm Hg on 2 separate occasions in ocular hypertensive and high-tension glaucoma eyes. All glaucomatous eyes had characteristic glaucomatous optic neuropathy and associated achromatic automated perimetry defect. Relative retinal nerve fiber layer internal reflectivity was measured on optical coherence tomography images using a software program of our own design. RESULTS: We enrolled 98 eyes (19 normal, 34 ocular hypertensive, 17 high-tension glaucoma, and 28 low-tension glaucoma). Relative internal reflectivity was less in eyes with glaucoma than in normal (P<.001, t test) and ocular hypertensive eyes (P<.001, t test). There was no difference in relative internal reflectivity between normal and ocular hypertensive eyes (P =.32) and between eyes with high-tension glaucoma and low-tension glaucoma (P =.43). Internal reflectivity correlated with mean deviation on achromated automatic perimetry (r(2) = 0.49, P<.001, quadratic regression analysis). CONCLUSION: Relative retinal nerve fiber layer internal reflectivity may provide useful information about the extent of retinal nerve fiber layer injury in glaucoma. Arch Ophthalmol. 2000;118:1044-1047

Adult↗

PubMed2001

Improving ultrasound reflectivity and stability of echogenic liposomal dispersions for use as targeted ultrasound contrast agents.

Targeted echogenic liposome dispersions for ultrasonic enhancement of vasoactive and pathological components of endothelium and atherosclerosis have recently been developed. The component lipids required for acoustic and targeting properties include phosphatidylcholine, phosphatidylethanolamine phosphatidylglycerol (PG), and cholesterol (CH), initially in a 60:8:2:30 mol % ratio. Component lipids, lyophilization, sugars, and freezing conditions were varied to optimize acoustic ultrasound reflectivity and acoustic stability. Echogenic liposome dispersions were made by using the dehydration-rehydration process. The lipid concentrations were varied (CH in the range 1 to 40 mol % and PG from 1 to 16 mol %). Variations in type and concentration of sugars were examined. The effect of freezing conditions and re-lyophilization was examined. Ultrasound reflectivity was assessed by using a 20-MHz intravascular ultrasound catheter and computer-assisted videodensitometry. Ultrasound reflectivity was optimized at a CH concentration of 10 mol %; PG concentration variation had essentially no effect on initial values of echogenicity. Optimal acoustic stability was observed with concentrations of 10-15 mol % CH and with a PG concentration greater than 4 mol %. Preparations made with 0.2 M mannitol were more ultrasound reflective than those made with lactose, trehalose, and sucrose. Re-lyophilization and freezing temperatures below -20 degrees C increased ultrasound reflectivity. We optimized the ultrasound properties of echogenic liposomal dispersions, the conditions of which provide some insight into the underlying lipid structures responsible. The preparations developed are now more stable and acoustically reflective than our previous preparations. This advances the development of echogenic lipid dispersions as targeted ultrasound contrast agents for use in general ultrasound as well as cardiovascular imaging.

Carbohydrates↗

PubMed2005

Tooth caries detection by curve fitting of laser-induced fluorescence emission: a comparative evaluation with reflectance spectroscopy.

BACKGROUND AND OBJECTIVES: Nitrogen laser-induced fluorescence (LIF) spectra of sound tooth consists of two broad bands centered at 440 and 490 nm, with two apparent side bands on either side. In order to locate the exact peak position of these bands and to effectively utilize the LIF spectral signatures for detection of tooth caries, the LIF spectra were curve-fitted using Gaussian spectral functions and the results were compared with those from diffuse reflectance spectral measurements. STUDY DESIGN/MATERIALS AND METHODS: The excitation light at 337.1 nm was guided to the sound and caries-affected tooth samples through the central fiber of the fiber-optic probe of a laser-induced fluorescence reflectance spectroscopy (LIFRS) system. Six surrounding fibers of the probe collect tooth fluorescence or diffuse reflectance from the lesion and direct it to a miniature spectrometer. The in vitro spectra were obtained from healthy enamel, dentin, and pulp level tooth caries. RESULTS: As compared to sound tooth, the caries tooth showed lower fluorescence and reflectance intensities in the 350-700 nm region. The deconvoluted peaks in the LIF spectra of sound tooth were found centered at 403.80, 434.20, 486.88, and 522.45 nm, whereas in the case of pulp level caries, a new peak was observed at 636.78 nm. Curve-fitted parameters, such as peak center, Gaussian curve area, full width at half intensity maximum (FWHM), and their ratios, were also found to vary with the stage of tooth caries. The ratios involving the 435 nm band, such as F405/F435, F435/F490, and F435/F525 ratios derived from curve-fitted areas and amplitudes, were found to be sensitive to discriminate between sound, dentin, and pulp level caries. Among the various diffuse reflectance spectral intensity ratios, the R500/R700 was found to be most sensitive to distinguish between pulp and dentin level caries. CONCLUSIONS: Nitrogen laser-excited fluorescence spectral studies were found to be more suited for detection of caries lesions. The LIF measurement with spectral analysis, done by curve fitting, outscores the diffuse reflectance methodology and shows the potential to screen different levels of tooth decay in a clinical setting.

Dental Caries↗

PubMed2005

Relationship between damaged fraction and reflected spectra of denaturing tissues.

BACKGROUND AND OBJECTIVES: During thermal therapy of tissue, such as induced by microwave heating, the initiation of denaturation should be monitored for proper thermal dosage. Additionally, denaturation should be confined to the pathologic volume, while preserving surrounding healthy tissue. The relationship between the damaged fraction and reflected spectra of denaturing tissues was investigated for a variation of the temperature of the tissues. STUDY DESIGN/MATERIALS AND METHODS: Denaturation of muscle, liver, and milk was studied in vitro by measuring the temperature-varying reflectance spectrum as heating occurs. A high-resolution fiber optic spectrometer was used to measure the reflectance changes. Temperature was monitored using a thermocouple embedded within the tissue along the side of the optical fiber probe. RESULTS: The values of average free energy to initiate denaturation in muscle and liver at about 60 degrees C were 94.8 and 96.3 kJ/mole, respectively. The reflectance spectra increased in amplitude for muscle and liver, and the peak shifted from approximately 700 to 720 nm in accordance with the damage fraction of tissue. The reflectance spectrum for milk was essentially unchanged. CONCLUSIONS: Spectral changes from heated muscle and liver reflect denaturation of proteins contained therein. The spectral information at 800 nm can be used to determine the average free energy for the initiation of denaturation.

Animals↗

PubMed1996

Neutron reflectivity studies of single lipid bilayers supported on planar substrates.

Neutron reflectivity was used to probe the structure of single phosphatidylcholine (PC) lipid bilayers adsorbed onto a planar silicon surface in an aqueous environment. Fluctuations in the neutron scattering length density profiles perpendicular to the silicon/water interface were determined for different lipids as a function of the hydrocarbon chain length. The lipids were studied in both the gel and liquid crystalline phases by monitoring changes in the specularly-reflected neutron intensity as a function of temperature. Contrast variation of the neutron scattering length density was applied to both the lipid and the solvent. Scattering length density profiles were determined using both model-independent and model-dependent fitting methods. During the reflectivity measurements, a novel experimental set-up was implemented to decrease the incoherent background scattering due to the solvent. Thus, the reflectivity was measured to Q approximately 0.3 A-1, covering up to seven orders of magnitude in reflected intensity, for PC bilayers in D2O and silicon-matched (38% D2O/62% H2O) water. The kinetics of lipid adsorption at the silicon/water interface were also explored by observing changes in the reflectivity at low Q values under silicon-matched water conditions.

1,2-Dipalmitoylphosphatidylcholine↗

PubMed1992

Human cone-pigment spectral sensitivities and the reflectances of natural surfaces.

The evolution of visual pigment spectral sensitivities is probably influenced by the reflectance spectra of surfaces in the animal's environment. These reflectances, we conjecture, fall into three main classes: i. Most inorganic and many organic surfaces, including tree bark, dead leaves and animal melanin pigmentation, whose reflectance increases gradually as a function of wavelength. ii. Living leaves, which contain chlorophyll, have a sharp reflectance peak at about 555 nm. iii. Flowers, fruit and other signaling colours that have co-evolved with animal vision typically do not reflect strongly at the same wavelength as leaves, and present a colour contrast against a leafy background. These three spectral functions we call 'grey-red', 'leaf-green' and 'leaf-contrast' respectively. This simple categorisation allows us to interpret the spectral tuning of human cone pigments in a way that might not seem possible given the wide variety of colours present in nature. In particular L-(red) cones will capture the highest possible proportion of photons reflected by leaves, and M-(green) cones will capture about 10% fewer photons both from leaves and from 'grey-red' surfaces. These observations have some clear implications for our understanding of the evolution of trichomacy and the trade-off between chromatic and luminance vision in Old-World Primates.

Humans↗

PubMed1991

Skin reflectance pulse oximetry: in vivo measurements from the forearm and calf.

This study describes the results from a series of human experiments demonstrating the ability to measure arterial hemoglobin oxygen saturation (SaO2) from the forearm and calf using a reflectance pulse oximeter sensor. A special optical reflectance sensor that includes a heating element was interfaced to a temperature controller and a commercial Data-scope ACCUSAT pulse oximeter that was adapted for this study to perform as a reflectance pulse oximeter. The reflectance pulse oximeter sensor was evaluated in a group of 10 healthy adult volunteers during steady-state hypoxia. Hypoxia was induced by gradually lowering the inspired fraction of oxygen in the breathing gas mixture from 100 to 12%. Simultaneous SaO2 measurements obtained from the forearm and calf with two identical reflectance pulse oximeters were compared with SaO2 values measured by a finger sensor that was interfaced to a standard Datascope ACCUSAT transmittance pulse oximeter. The equations for the best-fitted linear regression lines between the percent reflectance, SpO2(r), and transmittance, SpO2(t), values in the range between 73 and 100% were SpO2(r) = -7.06 + 1.09 SpO2(t) for the forearm (n = 91, r = 0.95) and SpO2(r) = 7.78 + 0.93 SpO2(t) for the calf (n = 93, r = 0.88). The regression analysis of the forearm data revealed a mean +/- SD error of 2.47 +/- 1.66% (SaO2 = 90-100%), 2.35 +/- 2.45% (SaO2 = 80-89%), and 2.42 +/- 1.20% (SaO2 = 70-79%). The corresponding regression analysis of the calf data revealed a mean +/- SD error of 3.36 +/- 3.06% (SaO2 = 90-100%), 3.45 +/- 4.12% (SaO2 = 80-89%), and 2.97 +/- 2.75% (SaO2 = 70-79%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Experimental and clinical evaluation of a noninvasive reflectance pulse oximeter sensor.

The objective of this study was to evaluate a new reflectance pulse oximeter sensor. The prototype sensor consists of 8 light-emitting diode (LED) chips (4 at 665 nm and 4 at 820 nm) and a photodiode chip mounted on a single substrate. The 4 LED chips for each wavelength are spaced at 90-degree intervals around the substrate and at an equal radial distance from the photodiode chip. An optical barrier between the photodiode and LED chips prevents a direct coupling effect between them. Near-infrared LEDs (940 nm) in the sensor warm the tissue. The microthermocouple mounted on the sensor surface measures the temperature of the skin-sensor interface and maintains it at a present level by servoregulating the current in the 940-nm LEDs. An animal study and a clinical study were performed. In the animal study, 5 mongrel dogs (weight, 10-20 kg) were anesthetized, mechanically ventilated, and cannulated. In each animal, arterial oxygen saturation (SaO2) was measured continuously by a standard transmission oximeter probe placed on the dog's earlobe and a reflectance oximeter sensor placed on the dog's tongue. In the first phase of the experiment, signals from the reflectance sensor were recorded while the dog was immersed in ice water until its body temperature decreased to 30 degrees C. In the second phase, the animal's body temperature was normal, and the oxygen content of the ventilator was varied to alter the SaO2. In the clinical study, 18 critically ill patients were monitored perioperatively with the prototype reflectance sensor. The first phase of the study investigated the relationship between local skin temperature and the accuracy of oximeter readings with the reflectance sensor. Each measurement was taken at a high saturation level as a function of local skin temperature. The second phase of the study compared measurements of oxygen saturation by a reflectance oximeter (SpO2[r]) with those made by a co-oximeter (SaO2[IL]) and a standard transmission oximeter (SpO2[t]). Linear regression analysis was used to determine the degree of correlation between (1) the pulse amplitude and skin temperature; (2) SpO2(r) and SaO2(IL); and (3) SpO2(t) and SaO2(IL). Student's t test was used to determine the significance of each correlation. The mean and standard deviation of the differences were also computed. In the animal study, pulse amplitude levels increased concomitantly with skin temperature (at 665 nm, r = 0.9424; at 820 nm, r = 0.9834; p < 0.001) and SpO2(r) correlated well with SaO2(IL) (r = 0.982; SEE = 2.54%; p < 0.001).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1992

Reflection and transmission pulse oximetry during compromised peripheral perfusion.

The performance of a reflection pulse oximeter and a transmission pulse oximeter was assessed during open-heart surgery when cardiac output, peripheral temperature, pulse pressure, and systolic pressure were low and vascular resistance was high. Before and after extracorporeal circulation (ECC) there was no difference in ability of the sensors to obtain readings and no difference in the accuracy of those readings. During partial ECC, especially after coronary artery bypass grafting, the reflection sensor gave readings earlier and at a lower pulse pressure. In addition, the transmission sensor failed to give any readings for 2 patients on partial ECC, for whom the reflection sensor did give readings. The accuracy of heart rate (HR) data was comparable for both sensors before ECC; however, during partial ECC, the reflection sensor tended to give values closer to the electrocardiographic HR. The accuracy of saturation data given by the reflection oximeter was comparable to that of the transmission oximeter. It is concluded that the accuracy of the saturation and HR data provided by the two methods of pulse oximetry are comparable, but that the reflection sensor is more likely to obtain readings under conditions of poorer peripheral circulation.

Adult↗

PubMed1995

Intraoperative reflectance oximetry in burn patients.

OBJECTIVE: Transmission oximetry sites for intraoperative monitoring are frequently difficult to find in burn patients, as standard transmission oximetry sites are often burned or contained within the operative field. The objective of this study was to determine if reflectance oximetry is of potential value in monitoring this group of patients. METHODS: A total of 16 operative procedures in a group of acutely burned adult and pediatric patients with an average age of 9.7 years (range, 10 months to 37 years), average burn size of 42% of the body surface (range, 15% to 94%), and average weight of 34.2 kg (range, 9 to 100 kg) were done with simultaneous transmission and reflectance oximetry monitoring. RESULTS: During these 16 procedures in a diverse group of acutely burned adult and pediatric patients, there was no significant difference in saturations derived from transmission and reflectance oximetry probes. In smaller children, adequate signal for reflectance probe monitoring was often detected in hyperemic sites, such as healed partial thickness burn. CONCLUSIONS: This is the first published report documenting both the clinical use of the reflectance oximetry in burn patients and the clinical use of the Nellcor Oxisensor II RS-10 reflectance oximetry probe (Nellcor Corporation, Hayward, CA). This technique can facilitate the intraoperative monitoring of acutely burned adult and pediatric patients in whom standard transmission oximetry sites are difficult to find.

Adult↗

PubMed1985

Reflectance spectrophotometry in the human ocular fundus.

Spectrometric investigations were carried out in normal human maculae and optic discs and in those with pathological findings (50 eyes in total). Reflection spectra were measured by illumination of various points of the fundus, using a highly sensitive photon-counting technique. It is necessary to distinguish diffusely reflected light from regularly reflected light, as we found marked differences in the spectra of diffusely reflected light between normal eyes and those with pathological findings. In optic atrophy cases, the intensity of light reflected from the optic disc (510-600 nm) was remarkably higher than normal. In findings of proliferative diabetic retinopathy, the reflected light intensity showed a steeper slope, beginning at 580 nm, in comparison with normal findings.

Diabetic Retinopathy↗

PubMed2006

Spontaneous basilar-membrane oscillation (SBMO) and coherent reflection.

In a previous report (in JARO) we have described a relatively high-frequency (15 kHz) spontaneous oscillation of the basilar membrane (SBMO) in a guinea pig ear; this oscillation was accompanied by a spontaneous otoacoustic emission (SOAE) at the same frequency. During the spontaneous oscillation and after it had subsided, the mechanical frequency response of the basilar membrane was measured by way of a wide-band random-noise stimulus, and it showed a number of spectral peaks, one of which having the frequency of the original oscillation. This pattern of peaks cannot be explained by assuming a single place of reflection in the cochlea. In this paper the process of 'coherent reflection' is artificially evoked in a three-dimensional model of the cochlea by imposing random place-fixed irregularities to the basilar-membrane impedance. It is shown that in the model a series of peaks arises in the frequency spectrum of the basilar-membrane response which phenomenon resembles the one found in the experimental animal. It is also shown that these peaks are actually due to superposition of the primary wave and a wave resulting from 'coherent reflection' which is reflected at the stapes. When the intensity of the acoustic stimulus signal is increased, the relative sizes of these peaks in the simulation diminish in about the same way as in the experiment. It is concluded that coherent reflection most likely is the cause of the 'extra peaks', and that this concept can also explain the observed level dependence of these peaks. The findings of this study lead to a minor refinement regarding the actual requirements for coherent reflection to arise.

Acoustic Stimulation↗