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Objectives: To evaluate the performance of a deep learning based Artificial Intelligence (AI) software for detection of glaucoma from stereoscopic optic disc photographs, and to compare this performance to the performance of a large cohort of ophthalmologists and optometrists. Methods: A retrospective study evaluating the diagnostic performance of an AI software (Pegasus v1.0, Visulytix Ltd., London UK) and comparing it to that of 243 European ophthalmologists and 208 British optometrists, as determined in previous studies, for the detection of glaucomatous optic neuropathy from 94 scanned stereoscopic photographic slides scanned into digital format. Results: Pegasus was able to detect glaucomatous optic neuropathy with an accuracy of 83.4% (95% CI: 77.5-89.2). This is comparable to an average ophthalmologist accuracy of 80.5% (95% CI: 67.2-93.8) and average optometrist accuracy of 80% (95% CI: 67-88) on the same images. In addition, the AI system had an intra-observer agreement (Cohen's Kappa, $\kappa$) of 0.74 (95% CI: 0.63-0.85), compared to 0.70 (range: -0.13-1.00; 95% CI: 0.67-0.73) and 0.71 (range: 0.08-1.00) for ophthalmologists and optometrists, respectively. There was no statistically significant difference between the performance of the deep learning system and ophthalmologists or optometrists. There was no statistically significant difference between the performance of the deep learning system and ophthalmologists or optometrists. Conclusion: The AI system obtained a diagnostic performance and repeatability comparable to that of the ophthalmologists and optometrists. We conclude that deep learning based AI systems, such as Pegasus, demonstrate significant promise in the assisted detection of glaucomatous optic neuropathy., Comment: 24 pages, 3 figures, 2 tables

The history of veterinary science in South Africa can only be appreciated, studied, researched and passed on to coming generations if historical sources are readily available. In most countries, material and sources with historical value are often difficult to locate, dispersed over a large area and not part of the conventional book and journal literature. The Faculty of Veterinary Science of the University of Pretoria and its library has access to a large collection of historical sources. The collection consists of photographs, photographic slides, documents, proceedings, posters, audio-visual material, postcards and other memorabilia. Other institutions in the country are also approached if relevant sources are identified in their collections. The University of Pretoria’s institutional repository, UPSpace, was launched in 2006. This provided the Jotello F. Soga Library with the opportunity to fill the repository with relevant digitised collections of diverse heritage and learning resources that can contribute to the long-term preservation and accessibility of historical veterinary sources. These collections are available for use not only by historians and researchers in South Africa but also elsewhere in Africa and the rest of the world. Important historical collections such as the Arnold Theiler collection, the Jotello F. Soga collection and collections of the Onderstepoort Journal of Veterinary Research and the Journal of the South African Veterinary Association are highlighted. The benefits of an open access digital repository, the importance of collaboration across the veterinary community and other prerequisites for the sustainability of a digitisation project and the importance of metadata to enhance accessibility are covered.

In the past, equine color vision was tested with stimuli composed either of painted cards or photographic slides or through physiological testing using electroretinogram flicker photometry. Some studies produced similar results, but others did not, demonstrating that there was not yet a definitive answer regarding color vision in horses (Equus caballus). In this study, a pseudoisochromatic plate test--which is highly effective in testing color vision both in small children and in adult humans--was used for the first time on a nonhuman animal. Stimuli consisted of different colored dotted circles set against backgrounds of varying dots. The coloration of the circles corresponded to the visual capabilities of different types of color deficiencies (anomalous trichromacy and dichromacy). Four horses were tested on a 2-choice discrimination task. All horses successfully reached criterion for gray circles and demonstration circles. None of the horses were able to discriminate the protan-deutan plate or the individual protan or deutan plates. However, all were able to discriminate the tritan plate. The results suggest that horses are dichromats with color vision capabilities similar to those of humans with red-green color deficiencies.

Effects of motion, implied direction in a static stimulus and displacement on postural control were examined independently. In Experiment 1, rotation of a random-dot stimulus was presented. In Experiments 2 and 3, photographic slides of natural scenes were used; participants closed their eyes during stimulus rotation to eliminate motion information. In Experiment 2, the stimulus was presented upright initially, then presented again with a tilt. In Experiment 3, the order was reversed to separate the effects of implied direction and displacement. Results showed that all information of motion, implied direction, and displacement had some effect on postural control, although visual information of motion has been presumed to have a principal effect on postural control. Results suggested that the effects of implied direction might reflect an immediate processing of information. The effects of displacement and motion might reflect a continuous processing of information.

We investigated the application of a fully automated computer algorithm for identifying vessels of the conjunctiva from their scleral surround, and compared measures of vessel width with established methods. Vessel widths at 101 locations (ranging from 20 to 140 microm), from 12 patients, were measured from film and digital images, using a variety of methods, and compared. Widths were measured manually, by semi-automated methods using grey level (densitometric) profiles taken from digital images, and by automated techniques set at different operating levels. Good intra-session repeatibility was obtained using the automated method with an operating sigma value of 3 pixels (16 microm) (mean difference 0.5 microm, 95% CI -8.5 to 9.4 microm) and manual calliper measurements from digitally created photographic slides (mean difference 0.4 microm, -9.3 to 10.1 microm). For comparison with other measures of width, the latter was used as the gold standard. Widths measured from film were slightly larger than those measured directly from digital images, although this effect was small (5 microm) for most vessels. Overall widths measured using the automated method, with a sigma value of 3 pixels, agreed best with the gold standard (inter-method repeatibility; mean difference 1.4 microm, -32.5 to 35.2 microm) although the automated method overestimated small widths (40 microm) and underestimated larger vessel widths (40 microm). Automated detection of vessels of the conjunctiva from digital images avoids manual and operator involved measures which are time consuming, and which preclude large patient studies. The resulting data may help in monitoring the vascular response of the conjunctiva to surgical or pharmacological intervention, and in describing vascular changes in response to ocular or systemic disease. The application of this algorithm to the study of retinal vessels is yet to be realised.

The purpose of this study was to compare the accuracy of a two-frequency (Root ZX) and a five-frequency (Endo Analyzer Model 8005) electronic apex locator under clinical conditions. Thirty-two teeth planned for extraction were used. The coronal portion of each canal was flared using Gates Glidden drills and Orifice Shapers. The canals were irrigated with 2.6% sodium hypochlorite. A K-type file was used to determine a separate working length in each canal using the electronic apex locators. The teeth were extracted and the apical 4 mm of each root canal was exposed along the long axis of the tooth. Photographic slides of each canal were projected and the file position in relation to the minor diameter was determined by two investigators. The mean distance between the electronic apex locator working length and minor diameter was 1.03 mm for the Endo Analyzer and 0.19 mm for the Root ZX. A paired sample t test showed that the Endo Analyzer had significantly longer readings beyond the minor diameter than the Root ZX (p0.0001). The ability to locate the minor diameter (+/- 0.5 mm) was 90.7% for the Root ZX and 34.4% for the Endo Analyzer Model 8005.

The aim of this study was to develop an aesthetic index for the evaluation of complete unilateral cleft lip and palate (UCLP) repair. The reproducibility and validity of this index were evaluated. A pilot study was devised, in which photographic slides of 50 subjects with UCLP were evaluated by seven orthodontic examiners on two separate occasions. After determining levels of agreement, the original index was modified for use in a clinical study. A field study was undertaken during an audit of cleft repair outcome in Perth, Western Australia. The subjects were graded using direct observation by two trained examiners. Standardized photographs of these subjects were taken at the same time. These were later graded by the same examiners independently on two separate occasions. Direct and indirect patient gradings could therefore be compared. A further field study involved the evaluation of the photographic slides of the original 50 subjects by 22 cleft surgeons. Reproducibility was determined by calculation of weighted kappa statistics. The intra-examiner agreement ranged from moderate to good and inter-examiner agreement from fair to good. Comparison of direct and indirect aesthetic evaluation revealed that the agreement was moderate to good, and no significant systematic bias existed. The new index offers advantages in simplicity and flexibility. Its reproducibility compares favourably with other aesthetic indices, and is not affected by the subject's age.

SUMMARY The aim of this investigation was to compare the repeatability of measuring enamel demineralization surrounding an orthodontic bracket using two techniques: computerized image analysis from digitally converted photographic slides and quantitative light-induced fluorescence (QLF). Fifteen human molars were halved and shaped to look like incisors. The teeth were individually numbered and orthodontic brackets bonded to the buccal surface. The crowns were covered with acid resistant varnish, except for windows approximately 1.5 x 3 mm adjacent to the gingival, occlusal, mesial, and distal edges of the bracket. The windows were variously exposed to a demineralizing gel for 0, 3, 7, or 14 days, and the acid resistant varnish was removed. Standardized photographic slides and QLF images of the teeth were taken. These were repeated after 1 week. The slides were converted to grey scale digital format and analysed using Image-Pro Plus 3.0. The QLF images were stored, processed, and analysed using customized software. All images were recoded for blind analysis. The four surfaces of the bracket were inspected and only areas of suspected demineralization were analysed. This was repeated after 1 week. The limits of agreement and mean difference between repeat readings of the area of demineralization were similar for both techniques (-0.04 ± 0.43 for photographs and -0.10 + 0.63 for QLF). Mean grey level (photographs) and mean loss of fluorescence from that area (AF) (QLF) showed acceptable limits of agreement. The Intra Class Correlation (ICC) was below 0.81 for the measurement of area from QLF, suggesting that random error needs to be reduced. There was evidence of systematic bias for the repeat readings of the grey levels from the photographs (P< 0.001). Enamel demineralization surrounding an orthodontic bracket can be measured reproducibly using these two techniques.

This study focuses on the visual characteristics of buildings illuminated with floodlights, primarily investigating how the visibility of building facades varies according to the distance from an observer. The authors also attempt to compare the visibility of building facades between direct observation and photographic slides. The changes in the appearance of a building facade when illuminated with floodlights can be gauged according to the two stages of “perception” and “recognition.” There is also a typical gap between the visual recognition distances for direct observation and for slide viewing. Generally the visual recognition distance is longer for direct observation that for slide viewing. This is shown by the close correlation between the two types of observation for visual recognition distance for all of the buildings studied.

This paper reviews the processes involved in the digitization, display and storage of medium-size collections of photographs, using mid-range commercially available equipment. Guidelines for evaluating the performance of these digitization processes based on aspects of image quality are provided. A collection of photographic slides, representing first-generation analogue reproductions of a photographic collection from the nineteenth century, is treated as a case study. Constraints on the final image quality and the implications of digital archiving are discussed. Full descriptions of device characterization and calibration procedures are given, and results from objective measurements carried out to assess the digitization system are presented. The important issues of file format, physical storage and data migration are also addressed.

Use of computers in education and research has completely changed the way things were made before. For example, a lecture to the students or the presentation of a paper to a Congress are completely different with respect to those of only a few decades ago, when blackboard, transparencies or photographic slides were used. There are many positive aspects of using computers, for example making a talk very attractive. However, there are also negative aspects. In this paper an analysis is presented of advantages and disadvantages I experienced and of consequences of using computers.

Two identical surveys were conducted with separate samples to determine consumer perceptions of the quality of five edible flower species. Participants were either members of a class that reviewed the history and uses of edible flowers at an annual, 1-day event (Garden Days) or Michigan Master Gardeners who attended a similar class. Participants were shown a randomized series of projected photographic slides of five edible flower species and asked to indicate whether they found the flower quality acceptable. The slides depicted a range of ratings of mechanical damage, insect damage, or flower senescence on a Likert reference scale (1 through 5) developed by the researchers. A flower rated 5 was flawless, while a flower rated 1 had substantial damage. Nearly one-half of all participants had eaten edible flowers before the study, and 57% to 59% had grown them for their own consumption, indicating many individuals had previous experience. Both samples rated flower quality equally and found pansy (Viola ×wittrockiana `Accord Banner Clear Mixture'), tuberous begonia (Begonia ×tuberhybrida `Ornament Pink'), and viola (Viola tricolor `Helen Mount') acceptable from stage 5 to 3. Both groups found the nasturtium (Tropaeolum majus `Jewel Mix') flowers acceptable at only rating 5. Garden Days participants rated borage (Borago officinalis) acceptable from ratings 5 to 3, while the Master Gardeners rated their acceptability from only 5 to 4. Participants also rated flower color (yellow, orange, and blue) as equally acceptable.

Health care professionals perform ophthalmoscopic examinations to detect pathologies of the eye, as well as to evaluate the effects of other diseases, such as high-blood pressure and diabetes. The ophthalmoscopic examination is given using an ophthalmoscope, a hand-held instrument consisting of an adjustable lens and a focused beam of light. The difficulty of the procedure lies in positioning the ophthalmoscope accurately and then correctly identifying the ocular disease symptoms — skills that improve with experience. To improve and accelerate the training of the student, we developed aVirtual Ophthalmoscopic Examination, a three-dimensional real-time computer simulation of the ophthalmoscopic procedure using virtual reality techniques. By navigating and manipulating the virtual ophthalmoscope in the simulation environment, the student learns how to position the instrument properly. Unlike other training aids that use photographic slides to show the full retina, theVirtual Opthalmoscopic Examination programme simulates an accurate view of the retina. By increasing the realism of the training, the transition from the training programme to live examination of patients will become less difficult. The programme was evaluated by graduate nursing students and was shown to be a promising training aid.

s English: The article describes how a compiled program for DOS/Windows manages a collection of pictures such as photographic slides, overheads, or computer images in one or more databases.

s English: A compiled program for DOS/Windows manages a collection of pictures such as photographic slides, overheads, or computer images in one or more databases. A database is comprised of a list of lines (screen width) beginning with the letter—number of the slide, for example, and a short description. The program places pictures in alphabetical order so they can be edited or marked if missing from the collection. Key words can be searched for in the database using Boolean logic. An associated file can contain 10 lines of details about each picture as edited by a built‐in word processor. This database can also be searched. Presentations can be saved in a files with specific lists of pictures for later recall and viewing or updating. The time to present slides in a particular talk can be calculated and saved for later editing. Context‐sensitive help is available and the contents of this paper can be read from the program.

Purpose Rolando's classification system for tear mucus ferning patterns subjectively assigns grades based on the size and spacing between ferns. Grade 1 and 2 patterns are considered "normal," whereas grade 3 and 4 patterns are often associated with keratoconjunctivitis sicca. This study was designed to examine the intraobserver and interobserver repeatability of Rolando's system. Methods Photographic slides (N = 418) of portions of tear ferning patterns were randomly assembled, numbered, and graded by two investigators (I1 and I2). I1 graded the slides twice; the slides were remixed under masked conditions between the first and second runs. I2 graded the slides once, independent of I1. Results For the four-grade system, intraobserver agreement was 85.41% (simple kappa = 0.75; 95% confidence interval ]CI] = 0.69-0.82). Interobserver agreement was 80.62% (kappa = 0.67; CI = 0.60-0.74) and 86.12% (kappa = 0.75; CI = 0.68-0.83) for the first and second runs of I1, respectively. Analysis of the ability to simply classify normal (grade 1 and 2) from abnormal (grade 3 and 4) patterns revealed intraobserver repeatability of 94.50% (kappa = 0.76; CI = 0.67-0.86). Interobserver agreement was 92.10% (kappa = 0.65; CI = 0.56-0.75) and 94.26% (kappa = 0.71; CI = 0.62-0.81) for the first and second runs, respectively. Conclusion Based on the high rate of agreement between intraobserver and interobserver trials, Rolando's grading system appears to be an easy and consistent method for the classification of tear ferning patterns.

Epiluminescence microscopy (ELM) is a useful method for improved diagnostic accuracy in early cutaneous melanoma. Conventional photographs of ELM images are commonly used for clinical research and documentation. Electronic images have advantages compared with photographs and are essential for medical informatics, computerized learning and telemedicine. Compression of electronic images allows a reduction in volume of data, but significant image deterioration may occur at high compression rates. We sought to study the diagnostic informativeness of compressed digital ELM images compared with conventional photographs. Fifty photographs of pigmented skin lesions, including 23 melanomas, were presented to eight dermatologists as photographic slides and as digital images with 30:1 Joint Photographic Experts Group (JPEG) compression. The diagnostic performance of the media and the readers was described in terms of sensitivity, specificity and areas under receiver operating characteristic curves (AUC). Agreement between the readings of the two types of media regarding the presence or absence of ELM criteria was assessed using kappa (kappa) statistics. The mean AUC was 0.81 (95% confidence interval [CI] = 0.73-0.90) for slides and 0.81 (95% CI = 0.72-0.90; P = 0.89) for digital images. Agreement between the readings of the two types of media regarding the presence or absence of ELM criteria ranged from kappa = 0.55 (95% CI = 0.22-0.88) for grey-blue area to kappa = 0.89 (95% CI = 0.74-1.00) for radial streaming. In conclusion, digital ELM images with 30:1 JPEG compression appear to be as informative as photographic slides when used to differentiate between melanoma and non-melanoma.

This study investigated the effect of group composition on judgments of African Americans. White male and female college students responded to photographic slides of female work groups in which the racial composition of the group was systematically altered to represent varying degrees of distinctiveness. Each participant judged the effectiveness of individual group members, as well as the competency of the overall group. Findings suggested that work groups which contained a distinctive (or solo) group member may affect judgments about similar others encountered later who share the solo's rare characteristic. Results are discussed in terms of the effect of these types of arrangements in organizational settings, and implications of these findings for practitioners and managers are discussed.

The efficacy of three different root canal instruments in maintaining the original shape of curved canals was evaluated. Acrylic blocks were prepared to simulate canals with 40 degrees and 60 degrees curvature. K-Flexofiles and Macfiles were used with a step-back technique utilizing an 'in/out' filing motion. The balanced-force technique was used with Canal Master 'U' instruments. Ten 40 degrees and 10 60 degrees canals were prepared with each instrument. The results were evaluated using superimposed photographic slides at x20 magnification to show the canals before and after the instrumentation. The width of the prepared canals was measured at their convex/concave point to determine the divergence of the instrumented canal shape from the original canal shape. The measurements were taken at the level of the apical foramen and 3 and 6 mm coronal to it. In this way it was possible to recognize all the defects created during the preparation of a canal. Among the tested instruments, the Macfile provoked minimal canal deviation (P = 0.05). The Canal Master 'U' was similarly effective (P = 0.05), but had the highest incidence of instrument fracture. The K-Flexofile demonstrated the most defects in canal preparation and canal deviation, particularly at the level of the apical foramen (P < 0.01).

The purpose of this study was to investigate the structure of emotional responses to pictorial stimuli within the affective space defined by orthogonal dimensions of positive affect (PA) and negative affect (NA). College student participants (N = 151) viewed 60 color photographic slides from the International Affective Picture System (Lang, Bradley, & Cuthbert, 1995) and rated their emotional responses to each slide using the Positive and Negative Affect Schedule (Watson, Clark, & Tellegen, 1988). Consistent with prediction, affective reactions to pleasant slides were characterized as high in PA, and low in NA. Unpleasant slides produced elevations on the NA scale, but contrary to expectation, also produced elevated ratings of PA, with the magnitude of PA scale scores increasing systematically with NA scale scores. The results suggest an interesting divergence between the structure of pictorially elicited affective reactions and that of ad hoc mood states. Directions for future research are discussed in relation to the unique properties of the slide viewing paradigm.

This study examined the norms that are salient to or accessed by subjects in response to scenes of frontcountry and backcountry settings. Inasmuch as salient norms are more likely to influence behavior, the concept of norm accessibility has utility for recreation and natural resource management. After viewing sets of photographic slides of either frontcountry or backcountry recreation settings, college students completed a questionnaire that elicited salient norms and measured students’ previous experience, knowledge, and frequency of visitation levels with the specific setting. Results suggest that while there seem to be few differences in the norm topics recalled or mean number of norms accessed by respondents in backcountry and frontcountry settings, there was slightly more group agreement in the norms accessed for the backcountry setting. The number of norms recalled by respondents was influenced by previous experience, frequency of contact with the setting, and level of knowledge with the recreationa...

I examined the impact of first names on ratings of physical attractiveness as judged by British undergraduate subjects using male and female full-face pictures presented on photographic slides. The photographs were identified with attractive names, unattractive names, or without any name indicated. Subjects rated the stimulus figures for physical attractiveness. Names accounted for approximately 6% of the variance in subjects' ratings of physical attractiveness. This effect was highly significant for pictures of women (p.001), but nonsignificant for pictures of men (p.05).

The Gustilo and Anderson classification system is widely used to categorize open fractures. To assess its interobserver reliability, 10 patients with open fractures had photographic slides taken of their wound before and after operative treatment. These slides were then shown to a group of orthopaedic surgeons. After an explanation of the Gustilo and Anderson classification system and each patient's pertinent history and physical examination, the physicians were asked to classify the fracture. Agreement among the various raters was determined by Kappa analysis, which is the preferred measurement of interobserver reliability for nominal data such as classification schemes. Kappa analysis demonstrated only moderate agreement among the observers classifying open fractures using the Gustilo and Anderson system. This seems to indicate that, although useful, the Gustilo and Anderson open fracture classification system does have limitations; studies and treatment recommendations based on it should be interpreted with caution.

Forty subjects responded to a set of 64 different combinations of linear displays and rotary controls presented by photographic slides. The subject's task was to rotate a control to increase the numerical value on the display. It was expected that response time for an arrangement having a strong stereotype would be faster than one with a weaker stereotype. Data showed there a strong relationship between these two measures of compatibility for horizontal displays with controls either on the top or bottom of the display; there was no significant relationship for any of the vertical layouts. Comparing horizontal and vertical displays, the average response times were 1.25 and 1.55 seconds and average stereotype strengths were .86 and .73, respectively. Thus on both criteria, horizontal displays were superior to vertical displays. Response time was found to be dependent on the magnitude of the component principle making the greatest contribution to the strength of the overall stereotype. In the case of horizontal displays this was the clockwise-to-right principle; for vertical displays it was Warrick's principle or, if this was not applicable, the scale-side principle.

The present study was designed to assess a monkey's perception of specific visual stimuli by measuring both the behavioral responses and duration of attention to the presentation of photographic slides. Five adult male cynomolgus macaques (Macaca fascicularis) were placed individually in an open field apparatus and presented a series of slides consisting of apples, a gorilla mask, a collage of colors, a human being, and a plain field. The slide of the gorilla mask followed by that of the human being received the most attention while the plain field received the least. In addition, the gorilla mask and human being elicited a range of behavioral responses with the higher ranking animals displaying a greater number of aggressive responses and the lower ranking animals displaying a greater number of submissive gestures. Taken together, these data would suggest that the slides of the gorilla mask and the human being were perceived by the monkeys as threatening. These results are consistent with a continuing theme observed among a number of studies of primate social perception — namely, that potentially threatening stimuli are a significant determinant of visual observing.

A digital indirect ophthalmoscope (DIO) was developed and tested for use in tele-ophthalmology screening for posterior and anterior segment diseases. Using custom software, images from the DIO were digitized, compressed, stored and transmitted to a centralized eye clinic for interpretation. A total of 43 subjects were primarily screened for glaucoma using the DIO, a hand-held fundus camera and a stereo fundus camera. The photographic slides from the stereo fundus camera were used as gold standards. Images (390 × 300 pixels × 3 bits) were stored using a laptop computer together with patient information. Image quality received at the central eye clinic was good and showed adequate diagnostic information. An ophthalmologist estimated cup–disc ratios and graded the quality of the images. The sensitivity and specificity of each instrument was calculated. A high sensitivity and specificity was found when using the DIO, indicating that it could be used in tele-ophthalmic screenings. Further modifications are needed to make the instrument more user-friendly and to enable it to be used with undilated pupils, so that it can be easily operated by health-care personnel in remote areas. The camera can also be used to image gross external eye pathology.

Although it is well known that visual stimuli affect olfactory performance, little is known about the reverse case: the influence of odor on visual performance. This study aimed to determine whether odors can enhance attention towards visually presented objects congruent with the odors. Sixty healthy participants were presented with four odors (orange, lavender, coffee, and liquorice) before and during the presentation of photographic slides containing one congruent and three incongruent objects with the presented odors. The participants' visual attention was assessed as the total number and time of eye fixations by using an eye tracking system. When the participants smelled an odor, they looked more frequently and longer at a corresponding object as compared to the odorless condition. In conclusion, our findings demonstrate for the first time an olfactory priming effect on visual selective attention: odor can increase attention towards a congruent visual object as compared to a non-odor condition. (C) 2010 Elsevier Ltd. All rights reserved.

This study describes a method for quantitative evaluation of visual resources of the Mediterranean coast of Israel. The method used visual characteristics of contrast, variety, competition, composition and harmony to identify visually preferred sites. Various coastal physical elements were used as a measurement scale of the characteristics. The study also examined the use of photographic slides vs. filed visit as a tool for visual resources evaluation of the Israeli coast.

Skeleton weed, centaurea juncea, is a declared weed in Western Australia because it competes with grain crops for nutrients and moisture. When it is found during harvesting, mechanised teams search and eradicate it. In an earlier report of field trials (Hartley et al, 1989) it was reported that search teams' detection rate was poor and since search teams had usually never seen skeleton weeds, visual discrimination learning was to be expected and observed during searches. The present study investigated the nature of this discrimination learning in a laboratory by developing a training programme of colour photographic slides of weeds in stubble. Subjects receiving specific training with feedback on their performance compared with those receiving pseudo-training showed a significant improvement in detections. Subsequently the benefit of the programme was validated in a field trial.

This poster session will describe a current needs assessment at the University at Buffalo that is designed to determine how a collection of digitized dental slides can meet the needs of dental researchers and practitioners. The University's School of Dental Medicine houses several collections of dental slides that depict various pathological conditions of the mouth and maxillofacial region, as well images of various human tissue types. These collections present a rich set of possibilities for pedagogical and diagnostic use by members of the dental profession. Previous studies have not directly addressed the description, organization, and use of digitized dental images, and how those efforts can address the needs of dental professionals. This leaves a gap in the research that this needs assessment can begin to fill.

Purpose. Probably the most common visual standard for employment in the transportation industry is best-corrected, high-contrast visual acuity. Because such standards were often established absent empiric linkage to job performance, it is possible that a job applicant or employee who has visual acuity less than the standard may be able to satisfactorily perform the required job activities. For the transportation system that we examined, the train crew is required to inspect visually the length of the train before and during the time it leaves the station. The purpose of the inspection is to determine if an individual is in a hazardous position with respect to the train. In this article, we determine the extent to which high-contrast visual acuity can predict performance on a simulated task. Methods. Performance at discriminating hazardous from safe conditions, as depicted in projected photographic slides, was determined as a function of visual acuity. For different levels of visual acuity, which was varied through the use of optical defocus, a subject was required to label scenes as hazardous or safe. Results. Task performance was highly correlated with visual acuity as measured under conditions normally used for vision screenings (high-illumination and high-contrast): as the acuity decreases, performance at discriminating hazardous from safe scenes worsens. Conclusions. This empirically based methodology can be used to establish a corrected high-contrast visual acuity standard for safety-sensitive work in transportation that is linked to the performance of a job-critical task.

F ILMS, videos, photographic slides, computer simulations and textbook descriptions can provide vicarious experiences that enhance learning about the natural world. However, if one wishes to capture the essence of an environment on a deeper level, these experiences are an inadequate substitute for "being there." Therefore, instructors of biology or environmental science, if you are looking for a new stimulus that will positively impact your teaching, I recommend a personal exploration of America's "last frontier," the state of Alaska.

Objective. To evaluate cytology laboratories and the performance of cytotechnologists for establishing efficient external quality control for Mexico's National Program for the Prevention and Control of Cervical Cancer. Material and Methods. During January and February 1998, an on-site evaluation of all cytology laboratories of the Ministry of Health found that only 70% of the microscopes were in adequate working conditions, reagents were out of date, and working conditions were sub-optimal. A program for external quality control based on proficiency testing was established for cytotechnologists. Fifty slide sets with 20 Papanicolaou slides and 10 photographic slides were prepared. The sets were given to the cytotechnologists for evaluation and again one year later by courier. Results. Twenty-one percent of microscopes were repaired and 9% replaced; reagents were distributed and laboratory facilities improved. Only 16% of cytotechnologists passed the initial proficiency test. Cytotechnologists received a refresher training course: one year later 67% of them passed the proficiency test. To ascertain that each slide was correctly diagnosed, 41 sets were rescreened by expert cytopathologists or cytologists and their diagnoses compared to the original ones. Thirty-seven sets had 86% to 96% concordance. Conclusions. This new system for external quality control of cervical cytology allowed the opportune and reliable evaluation of the performance of cytotechnologists.

The technological evolution has changed multiple areas of plastic surgery, including photography. The photograph is one of the instruments used most by the plastic surgeon, and it cannot be eliminated by technological changes. The principal change in photography is that images can be scanned through digital cameras instead of slides. Despite the multiple advantages that digital photography represents, many surgeons are resisting the change. One of the main reasons for this resistance is the large quantity of photographic slides that need to be digitized to be used at scientific conferences as well as in publications. The methods and existing techniques for digitizing slides are costly and time-consuming, and there is risk for loss of definition and image brightness. The authors present a simple, effective, fast, and inexpensive method for digitizing slides. This method has been validated by various plastic surgeons and is effective for use in multimedia presentations and for paper printouts with publication quality.

Summary In the last decade or so, there has been a renewed interest in the adult human vomeronasal organ (VNO). Studies have yielded sometimes disparate findings about the microscopic structure of the organ and its supporting tissues. Such varied descriptions may be due to examination of different regions of the VNO, individual variation of VNOs among humans, or the presence of multiple, non-homologous structures that bear false resemblance to the human VNO. A histological description of the spatial relationship of the human VNO to other nasal septal elements is needed to ensure that all investigators are examining the same regions and homologous structures. Histologically sectioned nasal septa from 22 human cadavers (1 child, 21 adults) were examined grossly and by light microscopy for the VNO. Using histological sections, the position of the VNO relative to other structures was estimated. Sections containing the VNO were retrospectively compared to scaled photographic slides of the unsectioned septa to identify surface landmarks. Human VNOs varied in anteroposterior and superoinferior position relative to the anterior nasal spine and the nasal cavity floor. In the absence of a visible duct opening, the only reliable surface marker, no consistent surface markings were noted for precise location. VNOs were frequently found superior to swellings associated with the paraseptal and/or septal cartilages. Such findings demonstrate that the human VNO is positionally variable, which may have contributed to previous conflicting findings on presence versus absence. Furthermore, our findings support recent suggestions that the VNO may have been misidentified by some investigators, and that its opening can be easily confused with other structures.

The goal of the present study was to examine size perception of objects depicted stereoscopically. Display size, target size, viewing distance, camera convergence distance, disparity information, and the scene background were manipulated. Subjects estimated the perceived height of a set of stereoscopic targets that were projected from photographic slides. The stereoscopic slides were taken with the targets either in a studio with a black background or outdoors with a backdrop of natural vegetation, using three camera convergence distances. The stereo slides were presented on two screens of different sizes and were viewed at three viewing distances. Disparity information was removed in half the trials. For the conditions examined, display and target size had a significant effect on perceived size; disparity and scene background had a small effect; viewing distance and camera convergence distance had a negligible effect. Interestingly, it was found that the range of estimates of perceived height was reduced compared to estimates of the actual targets. Furthermore, for the small display, the smaller targets tended to be perceived the same or a bigger size than the actual targets and the large targets tended to be perceived smaller than the actual targets.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Objective and methods Two experiments examined the impact of viewing unpleasant, pleasant, and neutral photographic slides on cold-pain perception in healthy men and women. In each experiment, participants viewed one of three slide shows (experiment 1 = fear, disgust, or neutral; experiment 2 = erotic, nurturant, or neutral) immediately before a cold-pressor task. Skin conductance and heart rate were recorded during the slide shows, whereas visual analog scale ratings of pain intensity and unpleasantness thresholds and pain tolerance were recorded during the cold-pressor task. Results Viewing fear and disgust slides decreased pain intensity and unpleasantness thresholds, but only the fear slides decreased pain tolerance. In contrast, viewing erotic, but not nurturant, slides increased pain intensity and unpleasantness threshold ratings on the visual analog scale in men, whereas neither nurturant nor erotic slides altered pain tolerance. Conclusions These results are consistent with a motivational priming model that predicts that unpleasant affective states should enhance pain and that pleasant affective states should attenuate it.

Decalcification and caries during orthodontic treatment still remains a problem. A method to protect the susceptible area beneath and adjacent to bonded attachments, independent of patient compliance, would be extremely beneficial. A clinical trial was performed using a dual-cured lightly filled BIS-GMA fluoride-releasing sealant. The barrier effect of this material on white spot formation, gingival irritation, and plaque accumulation during fixed orthodontic therapy was examined. Twenty patients with a total of 225 metal brackets placed on anterior teeth participated in this study. Brackets were placed in both arches in a conventional manner with a chemically cured, unfilled bonding resin; 112 teeth (every other tooth) received the barrier material after bracket placement, while the remaining 113 teeth served as controls. Intraoral photographic slides were taken before and after treatment and were evaluated blindly by 7 observers for white spot formation. Gingival and plaque indexes were recorded initially and consecutively every 6 months. Observation time ranged from 5 to 18 months. The results of this prospective clinical study indicated that there was no significant difference (P >.05) between the decalcification rates of the treatment or control groups. Likewise there was no added benefit with respect to plaque accumulation or gingival irritation.

Previous studies on the effects of surgical and rapid palatal expansion have been largely based on general skeletal and dental findings ascertained from radiographs and casts. The aim of this study was to measure and compare the soft tissue changes of the face during the expansion process and to determine the stability of any changes 1 year later. The sample consisted of 44 patients with unilateral or bilateral posterior crossbites. Twenty-four of the patients required a surgically assisted expansion procedure, and a second group of 20 patients were treated with orthopedic expansion. Ten measurements were made from standardized frontal facial photographic slides at 5 intervals of treatment: initial, bond appliance, stop expansion, debond appliance, and 1 year retention. Differences over time between the surgical and nonsurgical groups were analyzed by a 2 way multivariate analysis of variance (MANOVA) and post hoc t tests. Differences between initial and 1 year retention were found in the nasal widths (P < .001) of both surgical and nonsurgical groups. Other significant changes and trends were discussed. (Am J Orthod Dentofacial Orthop 1999;116:563-71)

The Flex-R file was compared with the Lightspeed nickel-titanium file in respect to canal center movement and final canal area after instrumentation. Thirty-eight root canals in extracted human molars were divided into two equal groups of 19, in all of which the angle of curvature ranged from 20 to 35 degrees. After mounting in a mold, each root was sectioned at two locations, providing an apical and coronal section. Pre- and postinstrumentation 35 mm photographic slides of each section were projected, traced, and then scanned into a computer. From these computerized pre- and postinstrumentation images, the movement of the canal center and the area of each canal were computed at both the apical and coronal sections. Results showed significant difference in the apical canal center movement and postinstrumentation area with the Lightspeed yielding smaller values in both cases. Coronally, the Flex-R Lightspeed instruments demonstrated no significant difference in canal movement or postinstrumentation area. No significant correlation was found between the angle of root curvature and canal movement or the angle of root curvature and postinstrumentation canal area.

The aim of this study was to assess the difference in opinion between patients and surgeons regarding the aesthetic outcome of reduction mammaplasty. A total of 34 women, who were more than 1 year post surgery, attended an outpatient clinic to assess their opinion of the aesthetic outcome of their breast reduction. A questionnaire was used to standardise their responses. Photographic slides were taken to record the frontal, left oblique and recumbent view of their torso. These slides were assessed by four consultant plastic surgeons who completed the same questionnaire, and were blinded as to the surgeon and patient. The majority of patients rated the aesthetic outcomes of their surgery significantly higher than the consultants. Scarring was the most frequent cause of dissatisfaction for both surgeons and patients. The consultants considered the scarring following Lejour reduction to be significantly better than that following the inferior mound reduction. The nipple was considered to be too high on the breast by 12% of women but they did not request correction of this. However, consultants thought this was a problem in 27% of cases. The aesthetic outcome of reduction mammaplasty was acceptable to the patients although surgical assessment indicates that there is scope for improvement. The main area of aesthetic dissatisfaction remains the postoperative scarring.

We have developed a photodensitometry method to evaluate the intensity of cutaneous erythema objectively. The method measures the optical density of photographic slides of cutaneous erythema. It combines techniques used commonly but separately by investigators: diffuse transmittance spectroscopy (which is a variant of diffuse reflectance spectroscopy) and photography. We have used this method to study photosensitivity in 22 volunteers who received increasing doses of ultraviolet radiation to the back. Our work confirms the usefulness of an important parameter in photobiology: the regression slope of the curve representing the erythema index, a function of the logarithm of the dose applied.

A simple and efficient psychophysical procedure is presented to quantify the visual conspicuity of a target in a complex (natural) scene. Measurements can easily and quickly be performed in the field or in complex environments. Only a few observers (typically 2-3) are need to achieve sufficient accuracy. The present study shows that this conspicuity measure predicts human visual search performance in realistic and military relevant complex scenario's. Also, conspicuity measured on photographic slides agrees with conspicuity measured in the field. This implies that the new conspicuity measure can be used in combination with photosimulation studies to optimize and evaluate the visual distinctness of displayed information.

Although the effects of emotional stimuli on event-related cortical potentials, heart rate, and memory have been extensively studied, the association of these variables in a single study has been neglected. The influence of pleasant, unpleasant, and neutral photographic slides on visual evoked potentials (VEPs), heart rate responses, and free recall, was investigated in 20 normal subjects. VEPs were recorded from Cz and Pz locations, and analyses were performed on both amplitudes and latencies of identifiable endogenous peaks (P2, N2 and P3), and mean amplitude in the 100-200-ms, 400-600-ms, and 600-900-ms latency ranges. An emotional effect was present on VEPs starting from about 282 ms on, as revealed by the N2, P3, and late components. Both pleasant and unpleasant slides yielded larger cortical positivity as compared to neutral ones. Peak latencies did not show any emotional effect. Heart rate data showed a deceleratory response that was larger to unpleasant slides. Free recall of the projected slides showed a better performance for emotional slides compared to neutral ones. VEPs and memory data showed the same pattern: both pleasant and unpleasant slides induced larger positivity in the event-related potentials and were better remembered than neutral slides. Positive correlations were found between the late negative VEPs component (600-900 ms), recorded from Cz, and heart rate deceleration (r = 0.62), and between P3 (at Pz location) and the number of remembered slides (r = 0.53).

Understanding the gingival tissue response in patients undergoing orthodontic treatment requires accurate pretreatment measurements of the width of the attached and keratinized tissue. Even though these may not be routinely recorded, it has been suggested that the orthodontic records can provide an accurate method of assessing the pretreatment keratinized tissue width. This clinical study was conducted to compare measures of the width of the keratinized tissue calculated from intraoral photographs and study models with direct clinical measures. Maxillary and mandibular study models and intraoral photographs were obtained from 33 patients. The width of the keratinized gingiva facial to the mandibular incisors was measured on two occasions to the nearest 0.5 mm. The width of the gingiva was calculated for the same teeth from two measures taken from projected photographic slides and the study models using a modification of Coatoam's technique. The method error was determined to be 0.43 mm for clinical measures and 0.32 mm for the calculated gingival tissue width. The reliability of measurement from orthodontic records was slightly greater than direct clinical measurement, with intraclass correlations of 0.93 and 0.90, respectively. The differences between the averaged clinical measure and averaged calculated measure for each tooth were small and not statistically significant (paired t-test, P = 0.21, 0.66, 0.24, 0.24 for teeth 23 through 26 respectively). The results indicate that carefully taken photographic slides and study models can provide an accurate measure of keratinized tissue width.

Convergent methodologies from studies of fear-potentiated startle in animals and studies of affective modulation of reflex blinks in humans were adapted in order to investigate infants' sensitivity to affective information conveyed by facial expressions of emotion. While 5-month-old infants viewed photographic slides of faces posed in happy, neutral, or angry expressions, a brief acoustic noise burst was presented to elicit the blink component of human startle. Blink size was augmented during the viewing of angry expressions and reduced during happy expressions. Infants did not show marked changes in behavioral reactions to the positive, neutral, and negative slides, although motor activity was slightly reduced during negative slides. Results suggest that, by 5 months, infants react to affective information conveyed by unfamiliar human faces. Potential mechanisms mediating the influence of affective stimuli on reflex excitability are considered.

The purpose of this study was to evaluate the transportation produced at the apical foramen by the use of stainless steel and nickel-titanium K-files #10, #15, #20, and #25 as a patency file. Thirty human maxillary lateral incisors were transversally cut at 4 mm from the apex and mounted in square pieces of silicone with special marks to ensure repositioning of the specimens. The specimens were randomly divided in two equal groups of 15. In group A, stainless steel K-files #10, #15, #20, and #25 were used as a patency file. In group B, a stainless steel K-file #10 followed by nickel-titanium K-files #15, #20, and #25 were used as in group A. Sodium hypochlorite was used as the irrigating solution. Photographic slides of the apical foramen of each specimen before instrumentation and after the use of each file size were taken. The photographic slides of each specimen were mounted in slide mounts, projected onto the same drawing paper, and superimposed according to the peripheral shape of the root. Transportation of the apical foramen was determined comparing the five drawings of each specimen. Transportation was detected in 18 of the 30 specimens; 9 in group A and 9 in group B. No statistically significant differences were seen between groups (p = 1.00).

Ten trails, one kilometre each, were evaluated by 15 persons for scenic beauty, recreational value and variety. All trails passed through commercially managed forests dominated by conifers. The trails were first evaluated by viewing computer simulations based on a series of graphical illustrations of forest landscapes, then from a slide show, and finally in the field. In the computer simulation and slide show, landscape pictures along the trail at an interval of 35â40 m were presented for 3â4 seconds. The ranks between slide show and field were slightly more similar than those between simulation and field. The mean correlation of 12 persons between the field ranking and assessment of either computer simulations or slide shows or graphics than scenic beauty or recreational value. Spearmanâs rank correlations computed from median scores of a group of 12 peers were clearly better than the average of individual persons varying from 0.6 to 0.9. The PDF includes an abstract in Finnish

• The search for an internationally acceptable facial grading system has resulted in an assessment of existing methods by several investigators. These studies were based on observations of video film taken of patients with varying degrees of facial malfunction. Although the grading systems were evaluated, the use of videotape has never been compared with clinical examination and its suitability for this type of work is, therefore, unknown. We used nine facial grading systems to compare the results of clinical observation with those of photographic methods of presentation. The latter included videotape, photographic slides, and a combination of the two. The correlation between clinical examination findings and findings of any of the photographic methods was poor, suggesting the need for a standard form of presentation when grading patients. The most consistent results were found with either clinical examination or photographic slides; videotape was the least reliable. ( Arch Otolaryngol Head Neck Surg . 1991;117:906-909)

Purpose: We have shown previously that proximal stimulation using size change can enhance or degrade accommodation step responses in open and closed loop conditions. The aim of the current experiment is to determine the relationship between the perceptual response to proximal stimulation based on size change and blur change for a range of target vergences. Methods: Perceptual thresholds for pure blur change, pure size change, coherent blur and size change and conflicting blur and size change were measured monocularly in 12 visually normal subjects (mean refractive error of -0.79D ± 2.41D and mean age 25.17 years ±3.10 years) using a 2-alternative forced-choice technique with 20 presentations per condition. Threshold estimates were obtained from psychometric functions using the bootstrap method. All subjects were fully corrected and had normal amplitudes of accommodation for their age. Threshold for proximal perception to blur only stimulation was established using target vergence changes of 0, 1, 2 and 3D. The effect of size change was then assessed at the same four levels of blur change. Stimuli were presented randomly with the position of the near and far vergences also randomised. This was repeated under four conditions: (1) Blur only. (2) Size only. (3) Size change coherent with the vergence change. (4) Size change conflicting with the vergence change. Targets consisted of pairs of photographic slides that contained strong monocular size and depth cues which were viewed successively in a 4D Badal lens system. On each trial the subjects compared the perceived proximity of the targets. Results: Considerable individual variation was found in the subject's perceptual responses to the four experimental conditions presented. The responses of all subjects were predicted by one of the following rules: (1) No effect of size. (2) Blur and size interact constructively. (3) No effect of blur. (4) Blur elicits a proximal response but size is used to determine the direction of the proximal effect. Without any size cue, eight subjects (66%) identified the direction of the vergence change correctly while the remaining subjects consistently perceived the target with lower dioptric vergence to be closer. The threshold required to accurately determine proximity from blur only cues was 2.27D ± 0.31D. In the absence of blur, size cues induced a proximal effect in 33% (n = 4) subjects. The combination of size and blur cues produced a variety of response patterns, some subjects’ responses were dominated by blur cues while others relied heavily on size stimulation. Conclusions: Our ability to perceive a target as close can be dependent upon either size and/or accommodation signals. Interactions between the stimuli of dioptric target vergence and target size were found to be additive for producing a perceived proximity response.