Just Noticeable Difference Research Articles

Abstract 13818: Health System Integrated Measurement-Based Care Using Patient-Reported Outcomes Assessment in Lower-Extremity Peripheral Artery Disease

Introduction: Peripheral artery disease (PAD) is a chronic disease that requires continuous and individualized disease-management to optimize patients’ symptoms, function and quality of life. Directly capturing patient-reported outcomes (PROs) in routine practice has the potential to increase the patient-centeredness of PAD care. We designed and implemented a system to measure health status within the workflow of a vascular specialty clinic. Methods: In a large academic center, from February 2020 until March 2022, an in-person patient navigation system (Yale PRO-QI) supported by a online data collection workbench was implemented to collect the EQ-5D, Peripheral Artery Questionnaire (PAQ), and VascuQol-6 as part of the outpatient consultations for lower-extremity PAD. Completion rates by month, and domain and summary scores for each PRO were derived per clinical phenotype: new patient/pre-procedural patient, post-procedural/follow-up patient. Results: Of 1071 eligible patient visits, 841 PRO assessments (n=446 unique patients) were completed, for an overall completion rate of 78.5% (monthly completion range 56.4%-100.0%). Patients had a mean age of 70.5±10.2 years, 39.4% were female, 9.6% Hispanics, 14.6% blacks, and 74.7% whites. Of the PROs administered, only the Symptom Stability, Treatment Satisfaction, and Quality of Life subscales of the PAQ were able to discriminate between the clinical phenotypes with differences that reached the minimal clinically important difference threshold of ~10 points ( Figure ). Conclusions: In anticipation of measurement-based care metrics that assess quality of care benchmarks for patient-centered PAD care, our health system integrated PRO workflow had a high response rate, and was able to successfully discriminate between highly symptomatic vs. stable patients as measured by validated disease-specific PRO benchmarks for PAD treatment success.

Mid-Term Outcomes of the All-Soft Quadriceps Tendon Autograft Are Noninferior to Hamstring Autograft in Primary Anterior Cruciate Ligament Reconstruction: Comparison With Minimum 5-Year Follow-Up

The purpose of this study was to compare the 5-year clinical and functional outcomes of the soft tissue quadriceps tendon (QT) to those of the hamstring tendon (HT) autograft METHODS: A retrospective review of patients undergoing ACL reconstruction using either soft tissue QT or double tendon HT autograft with at least 5 years of follow up was conducted. Surgical technique included anteromedial portal creation for the femoral tunnel and transtibial technique for the tibia. Graft fixation was achieved with interference composite screws for the QT and combination of interference composite screw and suture button for the HT cohort. The two groups were compared for differences in outcomes including International Knee Documentation Committee (IKDC) score, Lysholm score, return to sport, and complications. A total of 37 patients with QT autograft and 46 HT autografts were included in the study with a mean follow up of 69.9 months and 70.9 months, respectively. The QT group demonstrated a larger graft size on average (9.64mm vs. 7.90mm, p <0.001). The IKDC and Lysholm scores were similar between the two groups at 2-years postoperatively. At 5-years postoperatively, the QT group demonstrated significantly greater IKDC (p 0.018) and Lysholm (p 0.007) scores. The cohorts demonstrated similar rates of achieving minimal clinically important difference (MCID) thresholds at both 2 and 5 years postoperatively. The two groups also demonstrated comparable rates of return to sport, time to return, and postoperative complications. Although the QT autograft demonstrated increased patient reported outcome scores when compared to the HT at 5-years postoperatively, there was no clinically significant difference between the cohorts at 2 or 5 years postoperatively. The QT autograft is an effective alternative to HT autograft with non-inferior results to the hamstring autograft at mid-term follow up. Retrospective Comparison Study; Level of Evidence III LEVEL OF EVIDENCE: III, retrospective cohort study.

Identification and Classification of Aluminum Scrap Grades Based on the Resnet18 Model

In order to reduce the elemental species produced in the recycling and melting of aluminum scrap and to improve the quality of pure aluminum and aluminum alloys, it is necessary to classify the different grades of aluminum scrap before melting. For the problem of classifying different grades of aluminum scrap, most existing studies are conducted using laser-induced breakdown spectroscopy for identification and classification, which requires a clean and flat metal surface and enormous equipment costs. In this study, we propose a new classification and identification method for different grades of aluminum scrap based on the ResNet18 network model, which improves the identification efficiency and reduces the equipment cost. The objects of this research are three grades of aluminum scrap: 1060, 5052, and 6061. The surface features of the three grades were compared using a machine vision algorithm; three different datasets, using RGB, HSV, and LBP, were built for comparison to find the best training dataset for subsequent datasets, and the hyperparameters of learning rate and batch size were tuned for the ResNet18 model. The results show that there was a differentiation threshold between different grades through the comparison of surface features; the ResNet18 network model trained the three datasets, and the results showed that RGB was the best dataset. With hyperparameter optimization of the ResNet18 model, the accuracy of final classification and recognition could reach 100% and effectively achieve the classification of different grades of aluminum scrap.

Research on transformer condition evaluation based on oil chromatography differentiation threshold

As one of the important power transmission and transformation equipment, the reliability of transformer is directly related to the safe operation of power system. At present, the on-line monitoring technology based on dissolved gas analysis in oil is widely valued by researchers all over the world because it can continuously monitor the operation status of transformers and timely and effectively find the early faults of transformers. In this paper, the on-site oil chromatography data are differentiated and classified according to the voltage level of the transformer. The curve fitting method is used for statistical analysis and to build a distribution model. The cumulative probability is associated with the defect rate and failure rate of the equipment, and the corresponding threshold value is obtained by using the inverse cumulative distribution function as the attention value and warning value. By using this method, the attention values of the volume fraction of dissolved gas in oil and the gas production rate of dissolved gas in the existing national standards are improved, and the corresponding warning values are calculated to make the warning mechanism more flexible and reliable.

A comparative study of trait anxiety between female weightlifters and powerlifters

The aim of the study was to compare and wanted to see the sports competition anxiety between weightlifting and powerlifting. Sixty-eight female weightlifters and powerlifters (4 from each body weight category) who had participated in weightlifting and Powerlifting All India Inter University competition were selected as subject for the study. The participants were between the ages of 18 to 25. The Sports Competition Anxiety Test (SCAT) questionnaire designed by Martin (1990) was employed in this study. According to the literature review and researchers knowledge it was hypothesized that there might be significant difference between female weightlifters and powerlifters. For the analysis of the data independent‘t’ test was applied. The significant difference threshold was chosen at 0.05. There was no substantial difference between weightlifters and power lifters, according to the study's findings.

Indicators of subjective audiometry in the conventional frequency range in patients with COVID-19

Sensorineural deafness (SND) is a polyetiological disease. The cause of perceptual hearing loss can be, among other things, viral infections. As a result of the pandemic of the SARS-CoV-2 virus, a significant number of patients with various clinical manifestations of the disease COVID-19 are observed, among which there are lesions of the central nervous, cardiovascular, and other systems. In addition, in the publications of researchers, there are reports of damage to the auditory analyzer. However, there is not enough information in the literature regarding the study of hearing function in patients with COVID-19. The purpose of the study is to assess the state of auditory function according to subjective audiometry data in the conventional frequency range in pat ients with COVID-19. Materials and methods: An analysis of subjective audiometry data in the conventional frequency range was conducted on 36 patients with COVID-19 who complained of hearing impairment after the disease. The examination was performed using audiometers AS-40 (Interacoustics, Denmark) and MA-31 (Germany). Results and their discussion: To determine the indicators of subjective audiometry in patients with perceptual disorders of auditory function during COVID-19, we examined patients with complaints of decreased auditory function. Among 147 patients with COVID-19, during the survey, 51 people (34.7%) indicated certain disorders of the auditory system. During the instrumental examination of 47 patients with COVID-19 with complaints of hearing loss, we mainly observed sensorineural disorders of auditory function (36 people, 76.6%). Therefore, we analyzed subjective audiometry data in these patients. In most cases, we observed a gently descending type of tonal audiometric curve with the greatest increase in hearing thresholds for tones in the high-frequency region of the conventional range. The analysis of quantitative indicators of tone audiometry showed a significant increase in hearing thresholds for tones in the studied patients with COVID-19 compared to individuals of the control group. In patients with COVID-19, there is a significant (p&lt;0.01) increase in hearing thresholds to tones, starting at 2 kHz, compared to controls. This increase was most pronounced at frequencies of 6 and 8 kHz, where the values were 31.2±1.5 and 34.5±1.9 dB, respectively. Note that we did not find any significant differences in speech audiometry indicators in the studied patients compared to the indicators of the control group. However, some patients (7 people, 19.4%) complained of an inevitable deterioration in speech intelligibility. Moreover, three patients (8.3%) indicated that speech intelligibility impairment during communication occurred to them periodically. Also, we did not detect any significant changes in the indicators of suprathreshold tests – Lüscher intensity differential threshold test and SiSi test in the studied patients. Although at the same time, some patients (8 people, 22.2%) complained about poor tolerance of loud sounds, which may indicate the presence of FPZH (the phenomenon of accelerated increase in loudness), and, therefore, the presence of receptor damage to the auditory analyzer. Therefore, a third of patients (34.7%) may have a decrease in hearing function with the disease of COVID-19. Damage to the auditory system mainly (76.6% among all cases of hearing impairment) manifests as perceptual disturbances. Therefore, when examining patients suffering from COVID-19, we believe detecting disorders in the auditory system is advisable. Consequently, conducting an instrumental examination for those with hearing impairment complaints is advisable. On the other hand, when presenting patients with sensorineural deafness, it should be borne in mind that this may be related to a previous illness of COVID-19. Conclusions: 1. With COVID-19, a third of patients (34.7%) experience auditory function impairment due to damage to the auditory system, mainly perceptual in nature – 76.6% among all hearing impairment cases. 2. Hearing disorders in the case of COVID-19 can be observed directly during the disease, but more often, such manifestations appear somewhat delayed from the onset or after a particular time after the disease. 3. The most pronounced significant (p&lt;0.01) increase in hearing thresholds to tones in pat ients with COVID-19 with hearing impairment, compared to controls, occurs at frequencies of 6 and 8 kHz, where the values were 31.2±1.5 and 34.5±1.9 dB, respectively. 4. Patients with COVID-19 who have complaints of hearing impairment should undergo an instrumental audiological examination, first of all, subjective audiometry.

Robust watermarking based on blur‐guided JND model for macrophotography images

Macrophotography Images (MPIs) have recently emerged as an active topic due to the development of mobile phone camera technology. A large number of MPIs have been rapidly increasing in many rich visual services, such as smartphones or high-definition monitors. MPIs are often composed of sharp macroimage and blur background, which exhibit different perceptual properties that often lead to different just noticeable difference (JND) estimation. Inspired by this, we formulate the blur concealment (BC) as another factor to determine the total masking effect: the interaction is relatively straightforward with a limited masking effect in the sharp regions, and is complicated with a strong masking effect in the blur parts. Furthermore, texture and orientation adaption and color information weighting are separately incorporated into the contrast masking and color masking. Finally, considering both BC and masking effects, a novel robust watermarking framework based on the proposed blur-guided JND model for MPIs, targeting at further improving the MPIs copyright protection performance. Extensive experiments on MP2020 and Blur Detection data sets show that the applicability of the proposed JND model in the scenario of perceptually MPIs watermarking, and our proposed scheme can outperform the state-of-the-art watermarking schemes by providing better robustness performance at the uniform visual quality.

Pulse width and intensity effects of pulsed electric fields on cancerous and normal skin cells

Microsecond pulsed electric fields (PEF) have previously been used for various tumour therapies, such as gene therapy, electrochemotherapy and irreversible electroporation (IRE), due to its demonstrated ability. However, recently nanosecond pulsed electric fields (nsPEF) have also been used as a potential tumor therapy via inducing cell apoptosis or immunogenic cell death to prevent recurrence and metastasis by interacting with intracellular organelles. A large proportion of the existing in-vitro studies of nsPEF on cells also suggests cell necrosis and swelling/blebbing can be induced, but the replicability and potential for other effects on cells suggesting a complicated process which requires further investigation. Therefore, this study investigated the effects of pulse width and intensity of nsPEF on the murine melanoma cells (B16) and normal murine fibroblast cells (L929) through electromagnetic simulation and in-vitro experiments. Through examining the evolution patterns of potential difference and electric fields on the intracellular compartments, the simulation has shown a differential effect of nsPEF on normal and cancerous skin cells, which explains well the results observed in the reported experiments. In addition, the modelling has provided a clear evidence that a few hundreds of ns PEF may have caused a mixed mode of effects, i.e. a ‘cocktail effect’, including cell electroporation and IRE due to an over their threshold voltage induced on the plasma membrane, as well as cell apoptosis and other biological effects caused by its interaction with the intracellular compartments. The in-vitro experiments in the pulse range of the hundreds of nanoseconds showed a possible differential cytotoxicity threshold of electric field intensity between B16 cells and L929 cells.

Automated Mapping of Flood Inundation Areas using Cloud Based Processing Tools of Google Earth Engine for Efficient Disaster Management – A Case Study of Kerala Floods

Availability of reliable information on extent and impact of flood becomes critical for faster and efficient disaster management planning. Access to near realtime satellite data from optical and microwave sensors on Google Earth Engine (GEE) platform helps in rapid flood inundation mapping. Also, integration of Optical and Synthetic Aperture Radar (SAR) data from Sentinel series of satellites helps in detection of landuse/landcover features like Built-up, Agriculture Lands and Water bodies under flooding. The GEE platform provides extensive library tools for simultaneous pre-processing of SAR images and cloud free optical images from multiple satellites. In this research, Differential Thresholding and Differential Smoothening algorithms developed in GEE have been applied on Pre and Post SAR images for automatic identification of flood inundation areas. The inundated areas thus delineated were validated with inundation extents provided by the National Database for Emergency Management (NDEM). The methodology of automation developed in this study is applied to severe floods occurred in Kerala, India during August 2018. The sensitivity of polarization on mapping accuracy is estimated using Vertical- Horizontal (VH) and Vertical-Vertical (VV) modes available with Sentinel-1 data. The result indicates that VV mode of polarization provides better accuracy of 96% than VH mode. The coding is implemented in GEE environment with automation to provide extent of flood inundation for efficient management and mitigation planning during flood disasters.

Evaluation of Perceptual Difference in Dynamic Projection Mapping with and without Movement of the Target Surface

High-frame-rate visual feedback has been proven effective for projection mapping on quickly moving targets. However, the quantitative conditions of frame rates have not been elucidated. In particular, considering that the human dynamic visual acuity generally declines as the moving target velocity increases, it may be argued that the tracking accuracy required for projection mapping on moving targets can be lower than that required for fixed targets. To examine the above-mentioned conditions of frame rates, this study compares them based on two types of projection mapping systems having equivalent relative movements to each other: projection mapping from a fixed projector/camera system to a moving target and projection mapping from a moving projector/camera system to a fixed target. We examined the effects of the target movements by having stationary observers visually recognize and evaluate them. Using the weighted up-down method, we measured the frame time that provides a just noticeable difference (JND) to the projection mapping. We found that when the visual feedback is generated at a frame time of 2 ms, the frame time that provides a JND is 3.72 ms on average for fixed targets and 3.94 ms on average for moving targets: a 1%-level significant difference. Taking the individual differences and experimental errors into account, this is not a very large variation. This suggests that, in projection mapping to moving targets, we should realize a tracking accuracy as precise as that in projection mapping to fixed targets.

How much I moved: Robust biases in self-rotation perception

Vestibular cues are crucial to sense the linear and angular acceleration of our head in three-dimensional space. Previous literature showed that vestibular information precociously combines with other sensory modalities, such as proprioceptive and visual, to facilitate spatial navigation. Recent studies suggest that auditory cues may improve self-motion perception as well. The present study investigated the ability to estimate passive rotational displacements with and without virtual acoustic landmarks to determine how vestibular and auditory information interact in processing self-motion information. We performed two experiments. In both, healthy participants sat on a Rotational-Translational Chair. They experienced yaw rotations along the earth-vertical axis and performed a self-motion discrimination task. Their goal was to estimate both clockwise and counterclockwise rotations’ amplitude, with no visual information available, reporting whether they felt to be rotated more or less than 45°. According to the condition, vestibular-only or audio-vestibular information was present. Between the two experiments, we manipulated the procedure of presentation of the auditory cues (passive vs. active production of sounds). We computed the point of subjective equality (PSE) as a measure of accuracy and the just noticeable difference (JND) as the precision of the estimations for each condition and direction of rotations. Results in both experiments show a strong overestimation bias of the rotations, regardless of the condition, the direction, and the sound generation conditions. Similar to previously found heading biases, this bias in rotation estimation may facilitate the perception of substantial deviations from the most relevant directions in daily navigation activities.

The Minimal Clinically Important Difference, Patient Acceptable Symptom State, and Clinical Outcomes of Anterior Cruciate Ligament Repair Versus Reconstruction: A Matched-Pair Analysis From the SANTI Study Group

Background: There has been increasing interest in anterior cruciate ligament (ACL) repair because of theoretical advantages over ACL reconstruction; however, the contemporary literature has failed to provide high-quality evidence to demonstrate these advantages. Purpose: To compare the clinical and functional outcomes of ACL repair versus ACL reconstruction at a minimum follow-up of 2 years. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent ACL repair were propensity matched (based on demographics, time between injury and surgery, knee laxity parameters, presence of meniscal lesions, preoperative activity level, and sport participation), in a 1:1 ratio, to those who underwent ACL reconstruction during the same period. Isokinetic testing was used to evaluate strength deficits at 6 months postoperatively. Knee laxity parameters were evaluated at 12 months. Complications, return to sport, and patient-reported outcome scores were recorded at final follow-up. Results: In total, 75 matched pairs (150 patients) were evaluated. The repair group had significantly better mean hamstring muscle strength at 6 months compared with the reconstruction group (1.7% ± 12.2% vs −10.0% ± 12.8%, respectively; P < .0001). At a mean final follow-up of 30.0 ± 4.8 months, the repair group had a significantly better mean Forgotten Joint Score–12 (FJS-12) score compared with the reconstruction group (82.0 ± 15.1 vs 74.2 ± 21.7, respectively; P = .017). Noninferiority criteria were met for ACL repair, compared with ACL reconstruction, with respect to the subjective International Knee Documentation Committee score (86.8 ± 9.0 vs 86.7 ± 10.1, respectively; P < .0001) and side-to-side anteroposterior laxity difference (1.1 ± 1.4 vs 0.6 ± 1.0 mm, respectively; P < .0001). No significant differences were found for other functional outcomes or the pivot-shift grade. There were no significant differences in the rate of return to the preinjury level of sport (repair group: 74.7%; reconstruction group: 60.0%; P = .078). A significant difference was observed regarding the occurrence of ACL reruptures (repair group: 5.3%; reconstruction group: 0.0%; P = .045). Patients who experienced a failure of ACL repair were significantly younger than those who did not (26.8 vs 40.7 years, respectively; P = .013). There was no significant difference in rupture rates between the repair and reconstruction groups when only patients aged >21 years were considered (2.9% vs 0.0%, respectively; P = .157). The minimal clinically important difference and Patient Acceptable Symptom State (PASS) thresholds were defined for the ACL repair group. A significantly greater proportion of patients in the repair group achieved the PASS for the FJS-12 compared with their counterparts in the reconstruction group (77.3% vs 60.0%, respectively; P = .034). Conclusion: ACL repair was associated with some advantages over ACL reconstruction including superior hamstring muscle strength at 6 months and significantly better FJS-12 scores. However, the failure rate was significantly higher after ACL repair, and younger patients were particularly at risk.

Just noticeable differences in sound intensity of piano tones in non-musicians and experienced pianists

Changes in sound intensity are important components of piano performance. Previous research in this area has largely focused on perception of changes in pitch and timing, with little investigation of sound intensity. The present study used Musical Instrument Digital Interface (MIDI) technology to algorithmically control the key velocity, and thereby sound intensity, of consecutive piano tones. Non-musicians ( n = 20) and experienced pianists ( n = 30) played pairs of consecutive piano tones with 0–15 arbitrary units (a.u.) of change in key velocity, indicating whether they perceived the first, second, or neither tone as louder. All participants completed the test with C4, and a subset ( n = 24) with pitches C2 and C6 also. The mean just noticeable difference (JND) ranged from 2.71 to 4.48 a.u., corresponding to 0.68–1.22 dBC on the Yamaha Disklavier used to produce the stimuli. Experienced pianists demonstrated lower JND, which the authors theorize may be linked to listener motivation. When two tones were played with the same key velocity, participants tended to perceive the first tone as louder. The authors discuss a number of factors that may be relevant considerations for application of the findings in music and psychoacoustics research. These findings hold insight for music performance researchers, psychoacoustics researchers, and pedagogues.

Improved detection of hepatitis C virus-positive blood donors and determination of infection status.

In low-risk populations, variability in the sensitivity of current serological tests for Hepatitis C virus (HCV) blood donor screening may lead to the presence of false-positive results. This contributes to the unnecessary loss of blood donor samples as well as to difficulty in accurate donor counselling. The present study determined the optimal cut-off value of a chemiluminescent immunoassay for identification of HCV-reactive blood donors. In a retrospective cross-sectional analysis of 193 973 blood donations, 578 samples that were positive for HCV antibody in a chemiluminescent immunoassay and/or RNA screening tests were identified. Blood from 379 of these positive samples was available for retesting by a second confirmatory HCV immunoassay followed by a receiver operating characteristic (ROC) curve analysis. Donors were also recalled for a new analysis. Only 71 (18.7%) blood samples remained HCV-positive upon retesting, while 233 (61.5%) now tested negative and 75 (19.8%) yielding indeterminate results. A signal to cutoff ratio ≥4.32 was determined as the best differential threshold between a positive and negative result, increasing the positive predictive value from 27.3% to 66.7%. Using a higher threshold for an HCV-positive blood sample enhances the chemiluminescent immunoassay screening test´s accuracy and helps to improve donor counselling and notification processes.

PAMPAS: A PsychoAcoustical Method for the Perceptual Analysis of multidimensional Sonification.

The sonification of data to communicate information to a user is a relatively new approach that established itself around the 1990s. To date, many researchers have designed their individual sonification from scratch. There are no standards in sonification design and evaluation. But researchers and practitioners have formulated several requirements and established several methods. There is a wide consensus that psychoacocustics could play an important role in the sonification design and evaluation phase. But this requires a) an adaption of psychoacoustic methods to the signal types of sonification and b) a preparation of the sonification for the psychoacoustic experiment procedure. In this method paper, we present a PsychoAcoustical Method for the Perceptual Analysis of multidimensional Sonification (PAMPAS) dedicated to the researchers of sonification. A well-defined and well-established, efficient, reliable, and replicable just noticeable difference (JND) experiment using the maximum likelihood procedure (MLP) serves as the basis to achieve perceptual linearity of parameter mapping during the sonification design stage and to identify and quantify perceptual effects during the sonification evaluation stage, namely the perceptual resolution, hysteresis effects and perceptual interferences. The experiment results are scores from standardized data space and a standardized procedure. These scores can serve to compare multiple sonification designs of a single researcher or even among different research groups. This method can supplement other sonification designs and evaluation methods from a perceptual viewpoint.

Increased Handpiece Speeds without Air Coolant: Aerosols and Thermal Impact

This study assessed the impact of increased speed of high-speed contra-angle handpieces (HSCAHs) on the aerosolization of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surrogate virus and any concomitant thermal impact on dental pulp. A bacteriophage phantom-head model was used for bioaerosol detection. Crown preparations were performed with an NSK Z95L Contra-Angle 1:5 (HSCAH-A) and a Bien Air Contra-Angle 1:5 Nova Micro Series (HSCAH-B) at speeds of 60,000, 100,000, and 200,000 revolutions per minute (rpm), with no air coolant. Bioaerosol dispersal was measured with Φ6-bacteriophage settle plates, air sampling, and particle counters. Heating of the internal walls of the pulp chambers during crown preparation was assessed with an infrared camera with HSCAH-A and HSCAH-B at 200,000 rpm (water flows ≈15 mL min−1 and ≈30 mL min−1) and an air-turbine control (≈23.5 mL min−1) and correlated with remaining tissue thickness measurements. Minimal bacteriophage was detected on settle or air samples with no notable differences observed between handpieces or speeds (P > 0.05). At all speeds, maximum settled aerosol and average air detection was 1.00 plaque-forming units (pfu) and 0.08 pfu/m3, respectively. Irrespective of water flow rate or handpiece, both maximum temperature (41.5°C) and temperature difference (5.5°C) thresholds for pulpal health were exceeded more frequently with reduced tissue thickness. Moderate and strong negative correlations were observed based on Pearson’s correlation coefficient, between remaining dentine thickness and either differential (r = −0.588) or maximum temperature (r = −0.629) measurements, respectively. Overall, HSCAH-B generated more thermal energy and exceeded more temperature thresholds compared to HSCAH-A. HSCAHs without air coolant operating at speeds of 200,000 rpm did not increase bioaerosolization in the dental surgery. Thermal risk is variable, dependent on handpiece design and remaining dentine thickness.

Continuous Transition Impairs Discrimination of Electrotactile Frequencies.

Just-noticeable difference (JND), indicating the ability to accurately identify small differences in stimulation parameters, can be used to choose more sensitive stimulation methods as well as to calibrate tactile feedback in closed-loop human-machine interfacing. The JND is typically estimated using a forced-choice-discrimination task, in which two stimuli with different intensities are delivered separated by a brief pause. In the applications of tactile feedback, however, the stimulation parameters are typically modulated continuously. It is unclear if the discriminability of stimuli separated in time characterizes the ability to distinguish continuous changes in stimulation intensity. The present study compared the JND when pairs of frequency-modulated electrotactile stimuli were separated in time and presented continuously at two different baseline frequencies (20 and 60 Hz). The results showed that the JND was significantly smaller with time-separation between stimuli, but that the JND obtained with different types of transitions were in most cases linearly associated. In conclusion, the discriminability of time-separated stimuli is systematically better compared to that of the stimuli presented continuously. This can have an impact when calibrating the tactile feedback where the conventional method of the JND assessment might lead to an overly optimistic estimate of detectable changes.

S179 Naloxegol Provides Clinically Meaningful Symptom Improvement (PAC-SYM) in Patients With Opioid-Induced Constipation (OIC): A Pooled Analysis of Two Global Phase 3 Studies of Naloxegol

Introduction: OIC affects 40-80% of patients taking chronic opioid therapy. Naloxegol (Movantik®), a peripherally acting mu-opioid receptor antagonist (PAMORA) is effective in treating OIC symptoms in adults with chronic non-cancer pain as shown in two pivotal phase 3 trials (KODIAC 4/5; NCT01309841/NCT01323790). This pooled analysis evaluated symptom improvement utilizing the Patient Assessment of Constipation Symptoms questionnaire (PAC-SYM) in these two randomized, placebo-controlled trials. Methods: PAC-SYM scores were collected during KODIAC 4/5 as supportive efficacy measures. Scores range from 0 (absence of symptoms) to 4 (very severe) for each domain (abdominal, rectal, and stool symptoms). Minimal clinically important difference (MCID) thresholds of 0.5 based on literature and naloxegol real world studies, and 0.8 based on anchor method assessment were used to identify responders and non-responders. Results: 1337 patients (naloxegol (25mg, 12.5mg) or placebo (PBO)) were assessed in this analysis. The overall mean baseline values for PAC-SYM total, abdominal, rectal, and stool symptoms scores were 1.8, 1.7, 1.3, and 2.3, respectively, and were similar across groups. For MCID ≥0.5, there was a significantly higher proportion of PAC-SYM responders with naloxegol (25 mg: 69.49%; 12.5 mg: 65.63%) vs PBO (57.66%) at week 12. Odds ratios (OR) were 1.776 (p=0.0010) for 25mg and 1.501 (p=0.0143) for 12.5mg vs PBO. For MCID ≥0.8, higher proportions of PAC-SYM responders were also observed for naloxegol (25mg: 53.47%; 12.5mg: 45.74%) vs PBO (42.34%) at week 12. ORs were 1.709 (p=0.002) for 25mg and 1.217 (p=0.2368) for 12.5mg vs PBO ORs were generally consistent between MCID >0.8 and 0.5 (Table). At 12 weeks for both MCID thresholds, patients receiving naloxegol 25mg were >70% more likely to achieve clinically meaningful symptom improvement than with PBO.Subdomain analyses revealed dose-dependent responses; significantly greater responses in rectal and stool symptoms were achieved for 25mg vs. PBO (p< 0.05) at both MCID cut-offs (Figure 1a-d). Conclusion: OIC patients achieved clinically meaningful, constipation-related symptom improvement with naloxegol. These changes were dose dependent, with significant gains noted for 25mg at both MCID thresholds. Rectal and stool symptoms appear to drive these improvements consistent with the known effects of PAMORAs.Figure 1.: a-d. Likelihood of Achieving PAC-SYM MCID at Week 12: Naloxegol vs. Placebo (KODIAC 4/5; ITT Population) Table 1. - PAC-SYM Total Score: Proportion of Responders Achieving MCID at Week 12 (KODIAC 4/5; ITT Population) Placebo(N=359) a n(%) Naloxegol 12.5 mg(N=352) a n(%) Naloxegol 25 mg(N=331) a n(%) Naloxegol 12 mg vs. PlaceboOR(95% CI)p-value Naloxegol 25 mg vs. PlaceboOR(95% CI)p-value Proportion of PAC-SYM Responders Achieving MCID ≥ 0.5 207 (57.66%) 231 (65.63%) 230 (69.49%) 1.501(1.085, 2.078)0.0143 1.776(1.263, 2.497)0.0010 Proportion of PAC-SYM Responders Achieving MCID ≥ 0.8 152 (42.34%) 161 (45.74%) 177 (53.47%) 1.217(0.879, 1.687)0.2368 1.709(1.216, 2.401)0.0020 aNumber of analyzable subjects with complete PAC-SYM data for 12-wks.PAC-SYM, Patient Assessment of Constipation Symptoms questionnaire; MCID, minimal clinically important difference; OR, odds ratio; CI, confidence interval.

Spot The Difference

Minor defects can creep into display screens during the manufacturing process. Detecting them requires inspection tools and a method for quantifying these just-noticeable differences, says Radiant Vision Systems.

Feedforward and Feedback Modulations Based Foveated JND Estimation for Images

The just noticeable difference (JND) reveals the key characteristic of visual perception, which has been widely used in many perception-based image and video applications. Nevertheless, the modulatory mechanism of the human visual system (HVS) has not been fully exploited in JND threshold estimation, which results in the existing JND models not being accurate enough. In this article, by analyzing the feedforward and feedback modulatory behaviors in the HVS, an enhanced foveated JND (FJND) estimation model is proposed considering modulatory effects and masking effects in visual perception. The contributions of this article are mainly twofold. On the one hand, by analyzing the modulatory behaviors in the HVS, the modulatory mechanism is incorporated into JND estimation and a hierarchical modulation-based JND estimation framework is proposed for the first time. On the other hand, according to the response characteristics of visual neurons, modulatory effects on visual sensitivity are formulated as several modulatory factors to modulate the estimated JND threshold properly. Compared with existing models, the proposed model is developed in view of not only the masking effects but also the modulatory effects, which makes our model more consistent with the HVS. For different complex input images, experimental results show that the proposed FJND model tolerates more distortion at the same perceptual quality in comparison with other existing models.