Pre-determined Points Research Articles

How does buy service-based policy attract public transportation customers in Yogyakarta, Indonesia ?

The presence of public transportation (Trans Jogja and Friend Bus Jogja) is one of the solutions to overcome congestion and heavy traffic in Yogyakarta. However, in recent years, public transportation (Trans Jogja and Friend Bus Jogja) has had many problems, one of which is the lack of passenger numbers. It is because of these problems that occur in the field that the number of Trans Jogja passengers and Teman Bus Jogja is decreasing day by day. The purpose of this study is to find out the policies taken by the Yogyakarta Special Region government to increase and entice people to use public transportation. This study uses a qualitative descriptive analysis method that, as a whole, uses secondary data. This study found that there are four dimensions of service quality related to the Trans Jogja Minimum Service Standards: the tangibles dimension, the reliability dimension, the responsiveness dimension, and the assurance dimension. These four dimensions are running well and are in accordance with the applicable SPM, but these four dimensions need to be further improved. As for the factor that has reduced the interest of Trans Jogja users, namely the presence of online transportation services, Trans Jogja only operates at several predetermined points, and the operational time has also been determined. Unlike the case with online transportation, where online transportation is able to reach all areas in Yogyakarta and its operating hours are also flexible and in accordance with the wishes of prospective users.

Accuracy of linear mandibular measurements on conventional and cone beam computed tomography reconstructed panoramic radiographs

Introduction: The aim of the study was to evaluate and compare the precision of dimensional measurements in digital panoramic radiographs (PRs) and cone beam computed tomography (CBCT)-generated panoramic images. Materials and Methods: Ten dry human mandibles were subjected to direct anthropometric measurements, digital panoramic radiography, and CBCT scans. Vertical and horizontal measurements were made between predetermined points by two observers. Paired t-test was applied for the comparative analysis. p value <0.05 was considered statistically significant. Analysis of variance (ANOVA) was done followed by post-hoc Bonferroni test to correlate the measurements got by the three modalities. Results: Except for two vertical measurements (V2 and V4) there was statistically significant difference in relation to all the measurements. The highest mean difference was observed in relation to H4, which was 12.60 mm lesser on digital PR in comparison to the anatomic measurements. Also, except for two vertical measurements V1 and V5, all the other measurements were underestimated by the digital PR.Conclusion: Measurement done in reconstructed PR and digital PRs in the region of posterior tooth-bearing region and condylar region are statistically similar.

Configuration spaces of labeled points on a circle with two anchors

In this paper we calculate the homology of configuration spaces of n points on a circle, subject to the condition that two pre-determined points are included in the configuration.We make use of discrete Morse theory both to determine the Betti numbers, as well as to provide an explicit combinatorial description of the bases both for homology and cohomology.

Estimation of Hemi-Abdominal-Based Free Flap Weight Using Two Computed Tomography-Derived Measurements.

Accurate flap weight estimation is crucial for preoperative planning in microsurgical breast reconstruction; however, current flap weight estimation methods are time consuming. It was our objective to develop a parsimonious and accurate formula for the estimation of abdominal-based free flap weight. Patients who underwent hemi-abdominal-based free tissue transfer for breast reconstruction at a single institution were retrospectively reviewed. Subcutaneous tissue thicknesses were measured on axial computed tomography angiograms at several predetermined points. Multivariable linear regression was used to generate the parsimonious flap weight estimation model. Split-sample validation was used to for internal validation. A total of 132 patients (196 flaps) were analyzed, with a mean body mass index of 31.2 ± 4.0 kg/m2 (range: 22.6-40.7). The mean intraoperative flap weight was 990 ± 344 g (range: 368-2,808). The full predictive model (R 2 = 0.68) estimated flap weight using the Eq. 91.3x + 36.4y + 6.2z - 1030.0, where x is subcutaneous tissue thickness (cm) 5 cm lateral to midline at the level of the anterior superior iliac spine (ASIS), y is distance (cm) between the skin overlying each ASIS, and z is patient weight (kg). Two-thirds split-sample validation was performed using 131 flaps to build a model and the remaining 65 flaps for validation. Upon validation, we observed a median percent error of 10.2% (interquartile range [IQR]: 4.5-18.5) and a median absolute error of 108.6 g (IQR: 45.9-170.7). We developed and internally validated a simple and accurate formula for the preoperative estimation of hemi-abdominal-based free flap weight for breast reconstruction.

Empathic accuracy and interpersonal coordination: behavior matching can enhance accuracy but interactional synchrony may not

ABSTRACT The study considered two major facets of interpersonal coordination, namely, behavior matching (posture mirroring) and interactional synchrony, and investigated whether interpersonal coordination enhanced empathic accuracy. Interactional synchrony was further classified into simultaneous movement and interaction rhythms. Participants engaged in an eight-minute conversation with a same-gender unacquainted partner and an empathic accuracy task. Each participant viewed the interaction video and reported their thoughts and feelings at pre-determined points of time. Afterward, they rewatched the video and inferred the thoughts and feelings of their partners. The study employed OpenPose, 2D pose estimation software of human body, to quantify posture and bodily movement, which were used to determine coordination. The results indicated that behavior matching was positively associated with empathic accuracy, whereas rhythmic convergence in synchrony was negatively associated with accuracy in female dyads. The additional analysis explored the temporal relationship between coordination and accuracy, which indicated a cause–effect tendency during interactions.

Effect of photobiomodulation therapy on painful temporomandibular disorders

To evaluate the effect of photobiomodulation therapy (PBMT) on painful temporomandibular disorders (TMD) patients in a randomized, double-blinded, placebo-controlled manner. Participants were divided into a masseter myalgia group (n = 88) and a temporomandibular joint (TMJ) arthralgia group (n = 87) according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Both groups randomly received PBMT or placebo treatment once a day for 7 consecutive days, one session. The PBMT was applied with a gallium-aluminum-arsenide (GaAlAs) laser (wavelength = 810 nm) at pre-determined points in the masseter muscle (6 J/cm2, 3 regions, 60 s) or TMJ region (6 J/cm2, 5 points, 30 s) according to their most painful site. Pain intensity was rated on a 0–10 numerical rating scale (NRS) and pressure pain thresholds (PPT) and mechanical sensitivity mapping were recorded before and after the treatment on day 1 and day 7. Jaw function was assessed by pain free jaw opening, maximum unassisted jaw opening, maximum assisted jaw opening, maximum protrusion and right and left excursion. Data were analyzed with a mixed model analysis of variance (ANOVA). Pain intensity in arthralgia patients decreased over time (P < 0.001) for both types of interventions, however, PBMT caused greater reduction in pain scores than placebo (P = 0.014). For myalgia patients, pain intensity decreased over time (P < 0.001) but without difference between interventions (P = 0.074). PPTs increased in both myalgia (P < 0.001) and TMJ arthralgia patients over time (P < 0.001) but without difference between interventions (P ≥ 0.614). Overall, PBMT was associated with marginally better improvements in range of motion compared to placebo in both myalgia and arthralgia patients. Pain intensity, sensory function and jaw movements improve after both PBMT and placebo treatments in myalgia and arthralgia patients indicating a substantial non-specific effect of PBMT.

Методика оцінки релевантності інформації

The paper considers a methodology that makes it possible to determine the relationship between useful, distracting and interfering information. The proposed methodology allows you to evaluate the relevance of information supplied to a specialist. The situation when a specialist, based on the information received, makes certain decisions and performs the assigned tasks is considered. The regularity of the change in the probability of performing these functions on the amount of information received and information capacity has been established. The regularity of the change in the probability of performing these functions on the amount of information received and information capacity has been established. It is shown that the equation of information dynamics is an information analogue of T. Malthus's population model. This makes it possible to use well-known methods of analysis and extend the results obtained to other mathematical models. The procedure for selecting models that take into account various restrictive effects is considered. The factor of self-limitation is taken into account. The transition to an informational analogue of the Quetelet-Verhulst population model is justified. The external limiting factor is considered in the context of the influence of distracting and disturbing information. A predictive model for determining the pattern of changes in information ability is proposed. This model takes into account the speed of information flow under ideal conditions and the destructive influence of distracting and interfering information. The procedure for using the model is reviewed. This procedure provides an introduction to the calculations additional variable to take into account the influence of distracting and interfering information. The regularity of the change in the additional value and its relationship with information capabilities have been determined. It allows you to go to the procedure for finding out the potential value of the relevance indicator. A relationship has been established to determine the relevance indicators, which make it possible to take into account the potential amount of useful, distracting and interfering information. The relationship between the current and established values of relevance indicators has been established. The classification of the effects of distracting and interfering information is carried out. Relevance characteristics for the prevailing equal and weak influence of interfering and distracting information compared to useful information are analyzed. Methodology of using the relevance characteristics is considered. The ratios that make it possible to quickly assess the relevance indicator at predetermined control points and to determine the time to reach the control values of the observed values are established. The situation that arises under very strong and very weak influences of distracting and interfering information is analyzed.

Thermal Imaging of the Ocular Surface in Thyroid Eye Disease: A Comparison between Active, Inactive and Healthy Eyes

ABSTRACT Aim: To report the temperature differences on the ocular surface using infrared thermal imaging (TI) in thyroid eye disease (TED) and healthy eyes Methods: Prospective, consecutive, comparative case series comparing TI parameters between active and inactive TED with healthy controls. The data captured included baseline demography, activity of TED and the TI parameters. Area under the receiver operating characteristic curves (AUROC) were calculated for the temperature values to determine the sensitivity and specificity in distinguishing active from inactive TED. The Youden index and the predictor cut off values were also reported. Results: The study included 11 eyes with active TED, 46 eyes with inactive TED and 40 eyes healthy patients. Temperatures of pre-determined points on the ocular surface in degrees were compared between the three groups. Temperature at the caruncle, medial and lateral conjunctiva was noted to be significantly higher in the active TED group compared to inactive TED and healthy eyes. The most favorable Youden index (0.7) was noted for the caruncle with an AUROC value of 0.91, a sensitivity of 91% and a specificity of 79%. Correlation coefficient for the caruncular temperature with the corresponding CAS (clinical activity score) was 0.65 (95% C.I. 0.45 to 0.78, p < .0001). Conclusion: Thermal imaging in TED is an objective way of documenting surface inflammation by the surrogate marker of temperature change. It supplements CAS in clinically evident cases and could be useful in staging eyes with subtle clinical signs as well as those where signs have reduced following initiation of treatment.

Leaf identification using radial basis function neural networks and SSA based support vector machine.

In this research, an efficient scheme to identify leaf types is proposed. In that scheme, the leaf boundary points are fitted in a continuous contour using Radial Basis Function Neural Networks (RBFNN) to calculate the centroid of the leaf shape. Afterwards, the distances between predetermined points and the centroid were computed and normalized. In addition, the time complexity of the features’ extraction algorithm was calculated. The merit of this scheme is objects’ independence to translation, rotation and scaling. Moreover, different classification techniques were evaluated against the leaf shape features. Those techniques included two of the most commonly used classification methods; RBFNN and SVM that were evaluated and compared with other researches that used complex features extraction algorithms with much higher dimensionality. Furthermore, a third classification method with an optimization technique for the SVM using Salp Swarm Algorithm (SSA) was utilized showing a significant improvement over RBFNN and SVM.

Optimization of Elastic Properties of Composite Laminates Using Fiber-Optic Strain Sensors

The paper is devoted to combined computational and experimental approach for estimation of the elastic mechanical properties of structures made of laminate polymer composite materials (PCM). The computational component of the technique is connected with numerical simulation of mechanical behavior during quasistatic deformation of structures made of PCM. The experimental component is based on measurement of strains by fiber-optic strain sensors (FOSS) with Bragg gratings (FBG sensors), embedded in composite laminates or attached to them. The principle of the proposed method is based on the comparison of the data from FBG sensors, placed in the predetermined control points in the composite structure, with the data of numerical finite element modelling of the same structure. To refine the elastic constants in accordance with the information received from the FBG sensors, an algorithm is proposed, according to which the inverse problems are solved in order to ensure that the numerical and experimental results coincide with the specified accuracy. The implementation of the algorithm is demonstrated on the example case studies.

Estimation of Profunda Artery Perforator Flap Weight Using Preoperative Computed Tomography Angiography.

Given the relatively small size of thigh-based flaps and the possible necessity for a multiflap reconstruction, it is imperative to arrive at an accurate estimation of flap weight during preoperative planning. It was our objective to develop a novel technique for the preoperative estimation of profunda artery perforator (PAP) flap weight. All patients that underwent transverse PAP flap breast reconstruction at two institutions were retrospectively reviewed. Subcutaneous tissue thicknesses were measured on axial computed tomography angiography scans at several predetermined points. The distance from the inferior gluteal crease to the PAP was also recorded. Linear regression was used to estimate flap weight. A total of 18 patients (32 flaps) were analyzed. The median intraoperative flap weight was 299 g (interquartile range [IQR]: 235-408). The parsimonious model (R 2 = 0.80) estimated flap weight using the Eq. 77.9x + 33.8y + 43.4z - 254.3, where x is subcutaneous tissue thickness (cm) at the lateral border of long head of the biceps femoris at a level 4.5 cm caudal to the inferior gluteal fold, y is distance (cm) from the inferior gluteal fold to the dominant PAP, and z has a value of 1 if the patient was scanned in the supine position or 0 if prone. The aforementioned formula yielded a median estimated flap weight of 305 g (IQR: 234-402) and a median percent error of 10.5% (IQR: 6.1-16.2). The authors demonstrate a simple and accurate formula for the preoperative estimation of transverse PAP flap weight for breast reconstruction.

The use of Botulinum Toxin A in the surgical treatment of secondary cleft lip (secondary cheiloplasty): An objective and subjective evaluation of esthetic outcomes

The surgical correction of the cleft lip is a challenging one and obtaining consistently good esthetic outcomes sometimes can be elusive. Primary correction of cleft lip often results in secondary deformities requiring re intervention. Chemoimmobilsation with Botulinum Toxin A post-secondary cheiloplasty can help obtain favourable esthetic results. Aims: To evaluate the esthetic value of Botulinum Toxin A injection in secondary cleft lip surgeries and to assess the role of Botulinum toxin A in secondary cleft lip scars. Materials and Methods: 30 systemically healthy unilateral cleft lip patients reporting for secondary cheiloplasty procedure were taken up for the study. 10-12 units of Botulinum Toxin A was injected along pre-determined points on the lip. Objective (Photographic evaluation) and subjective (Patient questionnaire method) evaluation was carried out after one year post injection of Botulinum Toxin A. Results: Photographic evaluation revealed that the outcomes were mostly excellent or good. Subjective evaluation conducted showed that majority of patients were either happy or very happy with the esthetic results. Keywords: Botulinum Toxin A, cheiloplasty scars, esthetic evaluation, secondary cheiloplasty, secondary cleft lip, subjective evaluation, unilateral cleft lip.

Botulinum Toxin A- A valuable adjunct in improving the esthetic outcomes of surgically treated cases of unilateral primary cleft lip

In the surgical correction of the cleft lip, the surgeon faces numerous challenges which make the task of obtaining appreciable esthetic results an arduous one. A multitude of problems can present to the surgeon after the surgical repair of cleft lip, such as hypertrophic scar, peaking and notching. In such a scenario Botulinum Toxin A can help achieve improved esthetic results. Botulinum toxin type A is a powerful neurotoxin which is produced by the anaerobic organism Clostridium Botulinum and when injected into a muscle causes interference with the neurotransmitter mechanism producing selective, transient paralysis of the muscle, which in turn reduces scar contracture. Aims: To evaluate the esthetic outcome of Botulinum Toxin A injection in cleft lip surgeries and to evaluate the role of Botulinum toxin A in unilateral cleft lip scars. Materials and Methods: 30 healthy unilateral cleft lip patients reporting for cleft procedure were taken up for the study. 6-8 units of Botulinum Toxin A was injected (after test dose) along pre-determined points. Both objective (Photographic evaluation) and subjective (Patient questionnaire method) evaluation was carried out after 1 year. Results: Photographic evaluation revealed that majority of the patients had either excellent or good esthetic outcomes. Scar characteristics were evaluated and most patients were happy or very happy with the surgical results. Keywords: Botulinum Toxin A, Esthetic evaluation, Primary cheiloplasty, Subjective evaluation, Unilateral cleft lip

A New Inverse Explicit Flow Curve Determination Method for Compression Tests

Flow curves characterize plastic flow in materials and their accurate description is necessary to reproduce any forming process in simulations. For flow curve determination, laboratory uniaxial compression or tensile tests are conducted to record force-displacement during deformation. Flow stress is then calculated as the ratio of force to cross-sectional area. However, this assumption is invalid when the stress state during testing changes to non-uniaxial stress states, e.g. necking in tensile or bulging in compression tests. Alternatively, inverse methods deploy simulation models replicating experiments along with flow curves represented as an analytical equation. The parameters in this equation are then optimized by minimizing the error in simulation and experiments. An a priori guess of the analytical equation is difficult especially when the material behavior is complex e.g. Lüder or DRX flow curves, though. In this paper, a piecewise inverse method without using an analytical equation is therefore introduced and validated with flow curves for aluminum and copper under compression tests. The method determines flow curves points as tabular data at different displacement steps and hence it is easier to represent complex flow curves. Two different methods, a heuristic and an iterative one, are discussed. To minimize the error between simulated and experimental forces, the heuristic method uses an adaptive equation estimating flow stress using predetermined points and experimental force, whereas in the iterative approach the flow curve is adjusted iteratively to minimize the error. The results show that the heuristic method has a limited applicability e.g. for low friction tests, whereas the iterative method can estimate flow curves for generalized deformation conditions. Overall, the flow curves determined with the new method yield an error of less than 2% in the force estimation with simulated compression tests. The presented method hence determines accurate flow curves for forming simulations under multiaxial stress states without the necessity of analytical equations.

Sign Language in Brazilian Pharmacy Education

Objective. To evaluate undergraduate pharmacy curricula at Federal Institutions of Higher Education in Brazil in order to identify sign language courses and other content related to the provision of care to deaf patients. Methods. A cross-sectional, descriptive study was conducted between March and June 2017. Data were collected from the websites of undergraduate pharmacy education programs in Brazil. Sign language courses were classified according to type (mandatory or elective), nature (theoretical or theoretical-practical), course period and workload. The course contents were extracted and analyzed by content analysis. Results. Of the 35 schools of pharmacy included in the study, 18 (51.4%) included a sign language course in their curriculum. Eighteen (100%) of the sign language courses were elective, one (5.6%) was theorical-practical, 16 (89.0%) did not have a predetermined point in the curriculum for students to complete the course, and 11 (61.1%) had a workload equal to or greater than 60 hours. The main pedagogical content identified related to the teaching and learning of sign language. Conclusion. Learning sign language in undergraduate pharmacy is important for these professionals could provide humanistic and integral care to deaf patients. Therefore, there is considerable room for improvement in teaching sign language to undergraduate pharmacy students in Brazil.

An Automated System for Projection of Interior Construction Layouts

Layout of the interior works during building construction is time consuming and error prone. Given the cost involved, both for initial layout and for later rework where errors occur, researchers have sought to automate the layout task. Some have adopted marker-less augmented reality methods using heads-up displays or cameras, and others have proposed robots capable of marking out the works. The former encumber the workers, the latter are expensive to set up and are sensitive to site conditions, and neither has yet achieved the required accuracy. In this paper, we propose a more efficient approach to project relevant information from a building information model (BIM) onto the construction surface, directly augmenting the construction site with the design information. This is done using a portable system consisting of a 2-D laser scanner, an angled adjustable projector, and a camera. The system localizes itself within the already built outer walls using the laser scanner and the BIM model using a method derived from robotic mapping; it calibrates the projection correction parameters (keystone correction) using image analysis; and it projects the information with the angled projector. Testing results showed that the localization was accurate within a few millimeters and less than 3°, and the final projected image’s error was approximately 1 cm. Initial calibration requires less than 1 min and does not require specialist skills. The system automates the layout task, preserves accuracy, and can provide rich model information on any interior surface. Note to Practitioners —Measuring and marking up of the interior works during building construction is time consuming and error prone. Layout must be repeated for each trade: partitions, false ceilings, mechanical, electrical, and plumbing systems, and flooring and furnishings all require accurate marking of locations on floors, walls, and ceiling surfaces. Current automation is limited to the use of robotic total stations, but these only locate specific predetermined points. We propose a simple solution for automated layout, in which images from a building information model are projected directly onto the work surface. The system projects any desired information—drawings and images—onto the work surface (floor, walls, or ceiling) in the correct location, scale, and orientation. The prototype apparatus consists of a laser range scanner, a projector, and a camera. Projection of the work instructions directly onto the work surface is accurate and immediate. It saves the time required for workers to interpret and then mark up the dimensional information and it avoids the human error involved. The prototype is limited to environments in which computer projection is practical and currently requires planar surfaces.

An Evaluation of Systematic Versus Strategically-Placed Camera Traps for Monitoring Feral Cats in New Zealand.

Simple SummaryFeral cats are detrimental to native biodiversity worldwide. In New Zealand, feral cats are well established across much of the pastoral landscape, including forested areas. Feral cats, like many carnivore species, are elusive in their nature, and often occur at low densities, making them difficult to detect. Camera traps are a useful, non-invasive monitoring device, capable of ‘capturing’ feral cats as they pass by. Although cameras provide a wealth of information about animals within their field of view; there remains much to be learned about optimal camera trap placement within a landscape, if maximizing detection probability is the objective. Here, we report the results of two methods of camera trap deployment within similar sites: (1) systematic deployment on a grid and (2) strategic deployment, predominantly favoring habitats with assumed higher cat activity. Using the Royle–Nichols abundance-induced heterogeneity model (RN), which assumes detection probability and animal abundance are linked, we found that more cats were detected by cameras at forest margins than in mixed scrub or open farmland (but only slightly more than in forest locations). If maximizing cat detections is the aim, we recommend that cameras should be placed at the edges of forests (including forest fragments) whenever feasible. We deploy camera traps to monitor feral cat (Felis catus) populations at two pastoral sites in Hawke’s Bay, North Island, New Zealand. At Site 1, cameras are deployed at pre-determined GPS points on a 500-m grid, and at Site 2, cameras are strategically deployed with a bias towards forest and forest margin habitat where possible. A portion of cameras are also deployed in open farmland habitat and mixed scrub. We then use the abundance-induced heterogeneity Royle–Nichols model to estimate mean animal abundance and detection probabilities for cameras in each habitat type. Model selection suggests that only cat abundance varies by habitat type. Mean cat abundance is highest at forest margin cameras for both deployment methods (3 cats [95% CI 1.9–4.5] Site 1, and 1.7 cats [95% CI 1.2–2.4] Site 2) but not substantially higher than in forest habitats (1.7 cats [95% CI 0.8–3.6] Site 1, and 1.5 cats [95% CI 1.1–2.0] Site 2). Model selection shows detection probabilities do not vary substantially by habitat (although they are also higher for cameras in forest margins and forest habitats) and are similar between sites (8.6% [95% CI 5.4–13.4] Site 1, and 8.3% [5.8–11.9] Site 2). Cat detections by camera traps are higher when placed in forests and forest margins; thus, strategic placement may be preferable when monitoring feral cats in a pastoral landscape.

COSMOLOGY AND THE CONSTRUCTION OF SPACE IN THREE SAMA-BAJAU RITUALS

This paper examines how Sama-Bajau belief systems create space in ritual. In ritual, space ceases to be mere space but becomes an extraordinary site replete with meaning. This construction of a special place reflects, in its arrangement of markers, a social hierarchy comprising of, among others, ritual custodians, ritual celebrators or specialists, participant-audiences, and initiates. The arrangement of people, offerings and implements, as well as natural and man-made markers in ritual space may be construed as tangible artifacts of social relations that serve to link the visible and invisible worlds. In Sama-Bajau ritual, space takes shape as tangible and intangible cultural properties are made to relate to each other. On one hand, tangible properties such as roofed structures, temporary railings, and textile banners serve to mark off, in a physical sense, the sacred from the profane or the mundane. They may also announce the impending retreat of the quotidian giving way to the decidedly special, the spiritual or the divine. On the other hand, intangible properties such as music and dance create sonic and kinetic motifs that break silence and stillness of mundane space and time. As sound travels from its ritual source, the expanse of travelled space through human auditory senses, is felt and cognitively realized. As dance bursts forth from pre-determined points in space, it creates direction or trajectories as well as linear or curvilinear motifs across vertical, horizontal and sagittal planes, thus linking what in silence and stillness used to be unlinked elements in the landscape. This paper seeks to uncover the elements and contours of this rarefied space in ritual, and to see how these aspects of ritual space may help us achieve a better understanding of Sama-Bajau culture and identity. Keywords: Sama-Bajau ritual, sacred space, igal dance, kulintangan music, cosmology

Video recording and light intensity change analysis during cataract surgery using an animal model.

To estimate light exposure changes during cataract surgery through intraoperative images simulated from the "patient's perspective" using an animal model. In this experimental study, a 3-mm maculostomy was performed through the posterior globe's surface of 15 porcine eyes. Eyes were fixated to a glass slide and placed over an iPad camera. Video footage of a cataract surgery was obtained through the maculostomy for each eye, keeping light exposure parameters and focus constant. Seventy-five images, five from each eye, were extracted at pre-determined points, and mean gray value (MGV), a light intensity measure, was calculated. Differences in MGV between discrete surgical steps were evaluated using multiple one-sample t-tests. This technique allowed for the capture of a full-length cataract surgery through a 3-mm maculostomy. MGV range was 14.21-132.51. Light intensity was similar across surgeries and varied greatly through each procedure. A 24% decrease in MGV between post-hydrodissection and post-phacoemulsification stages was noted (difference - 18.36; 95% CI - 30.50 to - 6.22; p value = 0.006). A 22.4% decrease in light intensity was noted after phacoemulsification in comparison to the starting image (MGV difference - 16.78; 95% CI - 32.45 to - 1.12; p value: 0.0375). Light intensity was similar at the start and end of surgery (difference - 7.15; 95% CI - 19.35 to + 5.05; p value = 0.229). Light intensity changes through different steps of cataract surgery and may be minimal after phacoemulsification completion. This video and data may serve as informational and educational tools for surgeons and patients.

Physical thickness and group refractive index measurement of individual layers for double-stacked microstructures using spectral-domain interferometry

Abstract A non-destructive method for measuring the physical thickness and group refractive index of individual layers was proposed based on spectral-domain interferometry, which was realized to achieve real-time measurements using a mode-locked laser and an optical spectrum analyzer. As a double-stacked specimen, a microfluidic channel mold composed of a SU-8 photoresist and a silicon wafer was chosen. With areal scanning of the sample, a physical thickness map and a representative group refractive index value for each layer were obtained at the same time. The sample was measured 30 times consecutively at pre-determined points to estimate the repeatability of the physical thickness, for which the standard deviation was less than 10 nm. Moreover, a measurement comparison with two calibrated reference instruments was conducted. According to the comparative measurement results, physical thickness values obtained by the proposed method and with each comparative method were found to be in good agreement within expanded uncertainty levels.