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Abstract Background Trypanosoma brucei is the causative agent of human African sleeping sickness and Nagana in cattle. In addition to being an important pathogen T. brucei has developed into a model system in cell biology. Results Using Stable Isotope Labelling of Amino acids in Cell culture (SILAC) in combination with mass spectrometry we determined the abundance of >1600 proteins in the long slender (LS), short stumpy (SS) mammalian bloodstream form stages relative to the procyclic (PC) insect-form stage. In total we identified 2645 proteins, corresponding to ~30% of the total proteome and for the first time present a comprehensive overview of relative protein levels in three life stages of the parasite. Conclusions We can show the extent of pre-adaptation in the SS cells, especially at the level of the mitochondrial proteome. The comparison to a previously published report on monomorphic in vitro grown bloodstream and procyclic T. brucei indicates a loss of stringent regulation particularly of mitochondrial proteins in these cells when compared to the pleomorphic in vivo situation. In order to better understand the different levels of gene expression regulation in this organism we compared mRNA steady state abundance with the relative protein abundance-changes and detected moderate but significant correlation indicating that trypanosomes possess a significant repertoire of translational and posttranslational mechanisms to regulate protein abundance.

Abstract Background To study the specific antibody response to infection with Mycoplasma mycoides subsp. mycoides Small Colony (MmmSC), the agent of Contagious Bovine Pleuropneumonia (CBPP), we examined three panels of sera collected during three experimental infection trials in African cattle. The methods used included an in-house complement fixation test (CFT), a commercially available CFT, a competitive antibody ELISA (cELISA) and the immunoblotting test (IBT). In addition, lung tissue samples were examined by culture. Results A total of 89% (51/59) of all experimentally infected animals tested positive on at least one of the serological tests throughout the trial. The specific antibody titres to the MmmSC infection became positive first by CFT (6 to 9 days post infection [dpi]), followed by IBT (9 to 13 dpi) and cELISA (13 to 16 dpi). Individual animals were found to display remarkably distinct seroconversion patterns, which allowed their classification into i) early high responders, ii) late high responders, and iii) low responders. In accordance with other studies, none of the present serological tests was capable of detecting all CBPP infected animals. Conclusion Comparison of the assays' performance in terms of sensitivity and specificity raises serious questions as to their reliability for identification of infected individuals in the field. In view of these limitations, a combination of CFT and cELISA can markedly improve CBPP diagnosis at single-animal level.

Abstract Background Mycoplasma mycoides subsp. mycoides SC is the pathogenic agent of contagious bovine pleuropneumonia (CBPP), the most important disease of cattle in Africa causing significant economic losses. The re-emergence of CBPP in Europe in the 1980s and 1990s illustrates that it is still a threat also to countries that have successfully eradicated the disease in the past. Nowadays, probe-based real-time PCR techniques are among the most advanced tools for a reliable identification and a sensitive detection of many pathogens, but only few protocols have been published so far for CBPP diagnosis. Therefore we developed a novel TaqMan®-based real-time PCR assay comprising the amplification of two independent targets (MSC_0136 and MSC_1046) and an internal exogenous amplification control in a multiplex reaction and evaluated its diagnostic performance with clinical samples. Results The assays detected 49 MmmSC strains from diverse temporal and geographical origin, but did not amplify DNA from 82 isolates of 20 non-target species confirming a specificity of 100%. The detection limit was determined to be 10 fg DNA per reaction for the MSC_0136 assay and 100 fg per reaction for the MSC_1046 assay corresponding to 8 and 80 genome equivalents, respectively. The diagnostic performance of the assay was evaluated with clinical samples from 19 experimentally infected cattle and from 20 cattle without CBPP and compared to those of cultivation and a conventional PCR protocol. The two rt-PCR tests proved to be the most sensitive methods and identified all 19 infected animals. The different sample types used were not equally suitable for MmmSC detection. While 94.7% of lung samples from the infected cohort were positively tested in the MSC_0136 assay, only 81% of pulmonal lymph nodes, 31% of mediastinal lymph nodes and 25% of pleural fluid samples gave a positive result. Conclusions The developed multiplex rt-PCR assay is recommended as an efficient tool for rapid confirmation of a presumptive CBPP diagnosis in a well-equipped laboratory environment.

Abstract Objective After reverse shoulder arthroplasty (RSA) external and internal rotation will often remain restricted. A postoperative alteration of the biomechanics in the remaining cuff is discussed as a contributing factor to these functional deficits. Methods In this study, muscle moment arms as well as origin-to-insertion distance (OID) were calculated using three-dimensional models of the shoulder derived from CT scans of seven cadaveric specimens. Results Moment arms for humeral rotation are significantly smaller for the cranial segments of SSC and all segments of TMIN in abduction angles of 30 degrees and above (p ≤ 0.05). Abduction moment arms were significantly decreased for all segments (p ≤ 0.002). OID was significantly smaller for all muscles at the 15 degree position (p ≤ 0.005), apart from the cranial SSC segment. Conclusions Reduced rotational moment arms in conjunction with the decrease of OID may be a possible explanation for the clinically observed impaired external and internal rotation.

Abstract Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides subsp. mycoides, is an important livestock disease in Africa. The current control measures rely on a vaccine with limited efficacy and occasional severe side effects. Knowledge of the protective arms of immunity involved in this disease will be beneficial for the development of an improved vaccine. In previous studies on cattle infected with M. mycoides subsp. mycoides, a correlation was detected between the levels of mycoplasma-specific IFN-γ-secreting CD4+ T lymphocytes and reduced clinical signs. However, no cause and effect has been established, and the role of such cells and of protective responses acquired during a primary infection is not known. We investigated the role of CD4+ T lymphocytes in CBPP by comparing disease patterns and post mortem findings between CD4+ T cell depleted and non-depleted cattle. The depletion was carried out using several injections of BoCD4 specific murine monoclonal antibody on day 6 after experimental endotracheal infection with the strain Afadé. All cattle were monitored clinically daily and sacrificed 28-30 days post-infection. Statistically significant but small differences were observed in the mortality rate between the depleted and non-depleted animals. However, no differences in clinical parameters (fever, signs of respiratory distress) and pathological lesions were observed, despite elimination of CD4+ T cells for more than a week. The slightly higher mortality in the depleted group suggests a minor role of CD4+ T cells in control of CBPP.

Abstract Background Femoral offset influences the forces at the hip and the implant stresses after revision THR. For extended bone defects, these forces may cause considerable bending moments within the implant, possibly leading to implant failure. This study investigates the influences of femoral anteversion and offset on stresses in the Wagner SL revision stem implant under varying extents of bone defect conditions. Methods Wagner SL revision stems with standard (34 mm) and increased offset (44 mm) were virtually implanted in a model femur with bone defects of variable extent (Paprosky I to IIIb). Variations in surgical technique were simulated by implanting the stems each at 4° or 14° of anteversion. Muscle and joint contact forces were applied to the reconstruction and implant stresses were determined using finite element analyses. Results Whilst increasing the implant's offset by 10 mm led to increased implant stresses (16.7% in peak tensile stresses), altering anteversion played a lesser role (5%). Generally, larger stresses were observed with reduced bone support: implant stresses increased by as much as 59% for a type IIIb defect. With increased offset, the maximum tensile stress was 225 MPa. Conclusion Although increased stresses were observed within the stem with larger offset and increased anteversion, these findings indicate that restoration of offset, key to restoring joint function, is unlikely to result in excessive implant stresses under routine activities if appropriate fixation can be achieved.

Abstract Background Parasitic wasps constitute one of the largest group of venomous animals. Although some physiological effects of their venoms are well documented, relatively little is known at the molecular level on the protein composition of these secretions. To identify the majority of the venom proteins of the endoparasitoid wasp Chelonus inanitus (Hymenoptera: Braconidae), we have randomly sequenced 2111 expressed sequence tags (ESTs) from a cDNA library of venom gland. In parallel, proteins from pure venom were separated by gel electrophoresis and individually submitted to a nano-LC-MS/MS analysis allowing comparison of peptides and ESTs sequences. Results About 60% of sequenced ESTs encoded proteins whose presence in venom was attested by mass spectrometry. Most of the remaining ESTs corresponded to gene products likely involved in the transcriptional and translational machinery of venom gland cells. In addition, a small number of transcripts were found to encode proteins that share sequence similarity with well-known venom constituents of social hymenopteran species, such as hyaluronidase-like proteins and an Allergen-5 protein. An overall number of 29 venom proteins could be identified through the combination of ESTs sequencing and proteomic analyses. The most highly redundant set of ESTs encoded a protein that shared sequence similarity with a venom protein of unknown function potentially specific of the Chelonus lineage. Venom components specific to C. inanitus included a C-type lectin domain containing protein, a chemosensory protein-like protein, a protein related to yellow-e3 and ten new proteins which shared no significant sequence similarity with known sequences. In addition, several venom proteins potentially able to interact with chitin were also identified including a chitinase, an imaginal disc growth factor-like protein and two putative mucin-like peritrophins. Conclusions The use of the combined approaches has allowed to discriminate between cellular and truly venom proteins. The venom of C. inanitus appears as a mixture of conserved venom components and of potentially lineage-specific proteins. These new molecular data enrich our knowledge on parasitoid venoms and more generally, might contribute to a better understanding of the evolution and functional diversity of venom proteins within Hymenoptera.

We report a novel visual illusion that is present in the natural environment. In attempting to cut a banana in half, many people make the side adjacent to the stem shorter, because they see it as longer than it is. This study tested the presence of the banana bisection illusion with outline drawings and a 3D realistic-looking plastic banana. According to Gibson (1966) illusions are the consequence of artificial and impoverished stimuli, such as line drawings. However, the banana bisection illusion was found with naturalistic-looking 3D stimuli. A second experiment with solid 3D plastic bananas found the illusion with and without the stem, but the illusion was larger with the stem present., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Sinonasal malignancy (SNM) is a heterogeneous group of diseases for which induction chemotherapy (IC) may reduce tumor burden. The purpose of this study was to characterize the response to IC in SNM as a prognostic factor through its effect on survival., Methods: Retrospective cohort of patients undergoing IC for SNM between 2010 and 2019 at our quaternary referral center., Results: Forty-two patients with advanced SNM were included in the analysis. Patients with a favorable response to IC had higher survival rates than those who had an unfavorable response (5-year OS: 66.8% vs. 9.7%; p < 0.001; PFS: 56.8% vs. 0%; p < 0.001)., Conclusions: Response to IC in our patient cohort was a prognostic indicator of overall response to treatment. Further elucidation of predictors of response is needed for appropriate patient selection., (© 2023 The Authors. Head & Neck published by Wiley Periodicals LLC.)

Background: Oral cavity cancer (OCC) is traditionally associated with smoking, but there is an increasing prevalence of the disease among non-smokers. This review investigates possible modifiable risk factors in the development of OCC in non-smokers (OCCNS)., Methods: PubMed, EMBASE, Web of Science, and Scopus were searched for publications prior to June 2021. Comparative studies investigating modifiable OCCNS risk factors were identified following PRISMA guidelines. Publication date, population size, and results were indexed. Study quality was assessed using MINORS (Methodological Index for Non-Randomized Studies). Factors examined by multiple studies were analyzed using random-effect meta-analysis framework., Results: Literature search resulted in 1,625 unique publications. 52 records met inclusion criterion, investigating alcohol (n = 22), chewing products (n = 18), diet (n = 7), dental health (n = 11), and medical comorbidities (n = 6)., Conclusion: This review demonstrates the paucity of large studies investigating OCCNS risk factors. Further investigation is warranted to help clinicians risk-stratify patients without traditional risk factors., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Objective: To evaluate whether differences in pediatric tonsillectomy use by race/ethnicity and type of insurance were impacted by the American Academy of Otolaryngology-Head and Neck Surgery's 2011 tonsillectomy clinical practice guidelines., Study Design: We included children aged <15 years from Florida or South Carolina who underwent tonsillectomy in 2004-2017. Annual tonsillectomy rates within groups defined by race/ethnicity and type of health insurance were calculated using US Census data, and interrupted time series analyses were used to compare the guidelines' impact on utilization across groups., Results: The average annual tonsillectomy rate was greater among non-Hispanic white children (66 procedures per 10 000 children) than non-Hispanic black (38 procedures per 10 000 children) or Hispanic children (41 procedures per 10 000 children) (P < .001). From the year before to the year after the guidelines' release, tonsillectomy use decreased among non-Hispanic white children (-11.1 procedures per 10 000 children), but not among non-Hispanic black (-0.9 procedures per 10 000 children) or Hispanic children (+3.9 procedures per 10 000 children) (P < .05). Use was greater among publicly than privately insured children (75 vs 52 procedures per 10 000 children, P < .001). The guidelines were associated with a reversal of the upward trend in use seen in 2004-2010 among publicly insured children (-5.5 procedures per 10 000 children per year, P < .001)., Conclusions: Tonsillectomy use is greatest among white and publicly insured children. However, the American Academy of Otolaryngology-Head and Neck Surgery's 2011 clinical practice guideline statement was associated with an immediate decrease and change in use trends in these groups, narrowing differences in utilization by race/ethnicity and type of insurance., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In seven experiments we examined haptic memory for location, item information, and orientation for 12 tangible pictures, geometrical forms, and letter shapes in the change task. The study evaluated the influence of stimulus familiarity on change task performance. In the change task, participants are exposed to an array of patterns and subsequently have to indicate which ones have been altered on a second array. We also sought to determine whether prior demonstrations of female advantages in the haptic change task were reliable (Heller et al., 2010). The present experiments failed to replicate gender differences, overall with large samples. When participants were told about the nature of the picture change they should anticipate (45° or 90° rotation, location exchange), comparable performance was found for the groups in Experiment 1. In another experiment, participants were not told what sort of change might occur, and higher performance was found for the 90° rotation group than for the location exchange and 45° groups. Participants benefited from explicit instructions about the nature of the change. Telling participants the names of the raised-line pictures during initial study improved both change performance with the pictures and subsequent recognition. Changes derived from the substitution of new tangible print capital letters were easier to detect than location exchanges of the letters. Changes from letters to geometrical shapes were easy to detect. High performance resulted when participants were told to indicate which tangible letters were turned (45° or 90°) or exchanged in a final experiment. The results suggest the importance of pattern familiarity in haptic spatial memory.

The aim of the present study was to clarify the mechanisms underlying body understanding by examining the impact of visual experience (magnification and reduction) on perception of hand size and neutral external objects (squares). Independent groups of participants were asked to look through a 2× magnification lens, a ½-× reduction lens, or a control UV filter and to make visual size judgments about square stimuli and their hands. In Experiment 1, participants used a measuring device with unmarked wooden slats orientated in horizontal and radial/vertical space for their visual judgments. In Experiment 2, participants used an upright frontal slat for visual length judgments of their hands to eliminate any potential foreshortening in viewing the measurement apparatus. The results from the two experiments demonstrate that participants significantly underestimated both the square stimuli and their hands when they viewed them under a reduction lens. While overestimation and underestimation of squares was found for females in Experiment 2, males generally underestimated the squares. However, overestimation was not seen when the participants viewed their hands under a magnification lens. Implications of these findings are discussed.

Purpose: To evaluate the anatomical closure rate and visual outcome in patients undergoing pars plana vitrectomy with internal limiting membrane peeling without dye enhancement and with indocyanine green or triamcinolone acetonide assistance., Methods: This is a retrospective, comparative interventional case series. The electronic charts of 435 eyes of 415 patients with idiopathic macular holes who underwent macula hole surgery were reviewed from January 2003 to April 2010. The patients were assigned to 3 groups: no dye assistance (Group 1), indocyanine green-assisted (Group 2), and triamcinolone acetonide-assisted internal limiting membrane peel (Group 3). The data were recorded for 3-, 6-, and 12-month follow-up visits. Main outcome measures were postoperative visual acuity and macular hole closure., Results: The overall macular hole closure rate with a single surgery was 94.7% (108 of 114). In Group 1: 91.4% (191 of 209), in Group 2: 94.1% (112 of 119), and in Group 3: 95.9% (93 of 97) achieved closure. Closure rate for holes that were ≤400 μm in diameter was 98.8% compared with >400 μm, which was 90.4% (P = 0.001). There was a statistically significant (P < 0.001) improvement from preoperative visual acuity to postoperative visual acuity in all groups across all time points. There was no statistically significant visual acuity difference among three groups. At 12-month follow-up, 77.7% in Group 1, 66.1% in Group 2, and 81.3% in Group 3 achieved 20/50 visual acuity or better., Conclusion: The study shows that good anatomical and functional results can be achieved with no dye and with indocyanine green or triamcinolone acetonide dye assistance for internal limiting membrane peeling during macular hole surgery. Overall, visual acuity levels did not differ among groups, although subanalysis of the results suggests subtle indocyanine green toxicity.

The present study compared the strength of the horizontal-vertical illusion in blindfolded sighted people with raised-line curves and three-dimensional (3-D) objects. Although the horizontal-vertical curvature illusion has been reported with raised-line stimuli in both vision and touch, it was not known whether similar haptic distortion would be found with 3-D objects. Similar overestimation of verticals was found with both types of stimuli in Experiment 1. Experiment 2 used bimanual unrestricted exploration at the body midline and stimuli horizontal on the table surface or in the frontal plane. In Experiment 2, illusion strength was substantially stronger when the stimuli were frontal and diminished overall for the horizontal group. The horizontal-vertical illusion was strong with optimal methods of presentation (free bimanual exploration) in Experiment 2, even where radial-tangential scanning could not be a causal factor in the frontal group. The results suggest that illusory distortion in haptics is not the result of the use of raised lines, and these patterns can be effective surrogates for 3-D objects.

In a number of experiments, blindfolded subjects traced convex curves whose verticals were equal to their horizontal extent at the base. Overestimation of verticals, as compared with horizontals, was found, indicating the presence of a horizontal-vertical illusion with haptic curves, as well as with visible curves. Experiment 1 showed that the illusion occurred with stimuli in the frontal plane and with stimuli that were flat on the table surface in vision and touch. In the second experiment, the stimuli were rotated, and differences between vision and touch were revealed, with a stronger illusion in touch. The haptic horizontal-vertical illusion was virtually eliminated when the stimuli were bimanually touched using free exploration at the body midline, but a strong illusion was obtained when curves were felt with two index fingers or with a single hand at the midline. Bimanual exploration eliminated the illusion for smaller 2.5- through 10.2-cm stimuli, but a weakened illusion remained for the largest 12.7-cm patterns. The illusion was present when the stimuli were bimanually explored in the left and right hemispace. Thus, the benefits of bimanual exploration derived from the use of the two hands at the body midline combined with free exploration, rather than from bimanual free exploration per se. The results indicate the importance of haptic exploration at the body midline, where the body can serve as a familiar reference metric for size judgments. Alternative interpretations of the results are discussed, including the impact of movement-based heuristics as a causal factor for the illusion. It was suggested that tracing the curve's peak served to bisect the curve in haptics, because of the change in direction.

Three experiments examined gender differences in picture location memory in the sense of touch involving the change task. In Experiments 1 and 2, blindfolded sighted participants felt 15 tangible raised-line pictures and memorized their locations for 8 min. Subsequently, they felt another set of raised-line pictures that were identical to the original set, but locations were exchanged for 6 of them. The change task required participants to indicate which raised-line pictures were moved to new locations and which were not moved. It was expected that females would show superior picture location memory compared with males. The results showed that females had a significantly higher number of correct picture location judgments than males in Experiment 1. No differences appeared between males and females on the change task when the task was much more difficult and the raised-line pictures were irregularly arrayed in the second experiment. Task difficulty was too high in Experiment 2, and a third experiment reduced the number of pictures in the irregular array to 12. Females performed better than males in Experiment 3. Gender differences in the change task are small in magnitude in touch as well as in vision. The results of the present experiments using touch are consistent with the larger literature in vision.

We examined haptic viewpoint effects in blindfolded-sighted (BS) and visually impaired subjects: early blind (EB), late blind (LB), and very low vision (VLV). Participants felt complex objects and matched tangible pictures to them. In experiment 1, the EB and BS subjects had similar overall performance. Experiment 2 showed that the presence of a detail on the target object lowered performance in the BS subjects, and that matching accuracy was lower overall for top views for the blind subjects. In experiments 3-5, EB, LB, VLV, and BS subjects made judgments about perspective pictures of a model house with more salient object details. In experiment 3, performance was higher for side views than for corner views. Elevated side views were identified more readily than elevated corner views in experiment 4. Performance for top views was higher than for elevated side views in experiment 5, given the relative simplicity of the top-view depictions and salient details. The EB and BS participants had somewhat lower matching accuracy scores than the other groups. We suggest that visual experience is helpful, but not essential for picture perception. Viewpoint effects may vary with experience and object complexity, but the relevant experience need not be specifically visual in nature.

In two experiments, we examined the effect of selective attention at encoding on repetition priming in normal aging and Alzheimer's disease (AD) patients for objects presented visually (experiment 1) or haptically (experiment 2). We used a repetition priming paradigm combined with a selective attention procedure at encoding. Reliable priming was found for both young adults and healthy older participants for visually presented pictures (experiment 1) as well as for haptically presented objects (experiment 2). However, this was only found for attended and not for unattended stimuli. The results suggest that independently of the perceptual modality, repetition priming requires attention at encoding and that perceptual facilitation is maintained in normal aging. However, AD patients did not show priming for attended stimuli, or for unattended visual or haptic objects. These findings suggest an early deficit of selective attention in AD. Results are discussed from a cognitive neuroscience approach.

A series of experiments was carried out to examine the effect of curvature on haptic judgments of extent in sighted and blind individuals. Experiment 1 showed that diameters connecting the endpoints of semicircular lines were underestimated with respect to straight lines, but failed to show an effect of visual experience on length judgments. In experiment 2 we tested are lengths. The effects of curvature on perceived path length were weaker, but were still present in this experiment. Visual experience had no effect on path length judgments. Another experiment was performed to examine the effect of repeated tracing (1, 5, 9, or unlimited number of traces) on judgments of the lengths of straight lines and diameters of semicircles. Judgments of extent were more accurate when subjects engaged in larger numbers of traces. There was no effect of number of traces on curve-height judgments, suggesting that subjects were not using height estimates to judge diameters of semicircles. In a further experiment we tested the effect of number of traces on curves that varied in height. Restricting subjects to a single trace magnified the effect of path length on judgments of the distance between the endpoints of curves. Additional experiments showed that curvature effects on diameter judgments were not eliminated when stimuli were in the frontal plane or when the curves were explored with the use of two hands. Arm support had no effect on judged length in experiment 7. A final experiment showed a robust horizontal vertical illusion in haptic perception of convex curves, with overestimation of the heights of the curves compared with their widths. The practical and theoretical implications of the results are discussed.

In the first three experiments, subjects felt solid geometrical forms and matched raised-line pictures to the objects. Performance was best in experiment 1 for top views, with shorter response latencies than for side views, front views, or 3-D views with foreshortening. In a second experiment with blind participants, matching accuracy was not significantly affected by prior visual experience, but speed advantages were found for top views, with 3-D views also yielding better matching accuracy than side views. There were no performance advantages for pictures of objects with a constant cross section in the vertical axis. The early-blind participants had lower performance for side and frontal views. The objects were rotated to oblique orientations in experiment 3. Early-blind subjects performed worse than the other subjects given object rotation. Visual experience with pictures of objects at many angles could facilitate identification at oblique orientations. In experiment 5 with blindfolded sighted subjects, tangible pictures were used as targets and as choices. The results yielded superior overall performance for 3-D views (mean, M = 74% correct) and much lower matching accuracy for top views as targets (M = 58% correct). Performance was highest when the target and matching viewpoint were identical, but 3-D views (M = 96% correct) were still far better than top views. The accuracy advantage of the top views also disappeared when more complex objects were tested in experiment 6. Alternative theoretical implications of the results are discussed.

We studied the impact of manner of exploration, orientation, spatial position, and configuration on the haptic Müller-Lyer illusion. Blindfolded sighted subjects felt raised-line Müller-Lyer and control stimuli. The stimuli were felt by tracing with the index finger, free exploration, grasping with the index finger and thumb, or by measuring with the use of any two or more fingers. For haptic judgments of extent a sliding tangible ruler was used. The illusion was present in all exploration conditions, with overestimation of the wings-out compared to wings-in stimuli. Tracing with the index finger reduced the magnitude of the illusion. However, tracing and grasping induced an overall underestimation of size. The illusion was greatly attenuated when stimuli were felt with the index fingers of both hands. Illusory misperception was not altered by the position in space of the Müller-Lyer stimuli. No effects of changes in the thickness of the line shaft were found, but there were effects of the length of the wing endings for the smaller, 5.1 cm stimuli. The theoretical and practical implications of the results are discussed.

Experiments were conducted to determine whether the haptic horizontal-vertical illusion occurs with solid, three-dimensional objects as well as with tangible lines. The objects consisted of round or square bases, with dowel rods projecting above them at heights equal to the widths of the horizontal bases. A negative illusion, with overestimation of horizontals, was found with free haptic exploration, but not with tracing with the fingertip. The negative illusion occurred when subjects felt wooden Ls and inverted Ts with a grasping, pincers motion of the index finger and thumb. The presence or absence of illusory misperception was dependent upon exploration strategy, since the negative illusion vanished with finger tracing. A negative illusion was also found when subjects adjusted a vertical dowel so that it was judged to be equal in extent to a round or square base. A general overestimation of judged size derived from the pincers response measure, but was not found with the use of a tangible ruler. Comparable illusory results are most likely when drawings and objects promote similar haptic scanning methods. The results were consistent with the idea that the orientation of an edge or line is more important than whether one explores a tangible line or a three-dimensional object.

Blindfolded sighted, congenitally blind, late-blind, and very-low-vision subjects were tested on a tangible version of the embedded-figures test. The results of ANOVAs on accuracy measures yielded superior performance by the very-low-vision and late-blind subjects compared with the blindfolded sighted and congenitally blind participants. Accuracy of the congenitally blind subjects was similar to that of the blindfolded sighted participants. However, all groups of blind subjects were significantly faster than the blindfolded sighted subjects. It is suggested that experience with pictures combined with haptic skill aid perceptual selectivity in touch.

This paper reviews recent research on the perception of tangible pictures by sighted people and those who are blind or have extremely low vision. Raised-line pictures are useful for evaluating spatial cognition in congenitally blind people. The ease or difficulty of picture recognition is shown to vary with complexity, familiarity, and categorical information. Blind people are able to use pictorial displays effectively, but may benefit from instruction when complex depictions of three-dimensional objects involve foreshortening.

We examined the effect of visual experience on the haptic Müller-Lyer illusion. Subjects made size estimates of raised lines by using a sliding haptic ruler. Independent groups of blind-folded-sighted, late-blind, congenitally blind, and low-vision subjects judged the sizes of wings-in and wings-out stimuli, plain lines, and lines with short vertical ends. An illusion was found, since the wings-in stimuli were judged as shorter than the wings-out patterns and all of the other stimuli. Subjects generally underestimated the lengths of lines. In a second experiment we found a nonsignificant difference between length judgments of raised lines as opposed to smooth wooden dowels. The strength of the haptic illusion depends upon the angles of the wings, with a much stronger illusion for more acute angles. The effect of visual status was nonsignificant, suggesting that spatial distortion in the haptic Müller-Lyer illusion does not depend upon visual imagery or visual experience.

Perception of raised-line pictures in blindfolded-sighted, congenitally blind, late-blind, and low-vision subjects was studied in a series of experiments. The major aim of the study was to examine the value of perspective drawings for haptic pictures and visually impaired individuals. In experiment 1, subjects felt two wooden boards joined at 45 degrees, 90 degrees, or 135 degrees, and were instructed to pick the correct perspective drawing from among four choices. The first experiment on perspective found a significant effect of visual status, with much higher performance by the low-vision subjects. Mean performance for the congenitally blind subjects was not significantly different from that of the late-blind and blindfolded-sighted subjects. In a further experiment, blindfolded subjects drew tangible pictures of three-dimensional (3-D) geometric solids, and then engaged in a matching task. Counter to expectations, performance was not impaired for the 3-D drawings as compared with the frontal viewpoints. Subjects were also especially fast and more accurate when matching top views. Experiment 5 showed that top views were easiest for all of the visually impaired subjects, including those who were congenitally blind. Experiment 5 yielded higher performance for 3-D than frontal viewpoints. The results of all of the experiments were consistent with the idea that visual experience is not necessary for understanding perspective drawings of geometrical objects.

We examined haptic perception of the horizontal in visually impaired people. Blind people (late blind and congenitally blind), persons with very low vision, and blindfolded sighted individuals felt raised-line drawings of jars at four angles. They had to demonstrate their understanding that water remains horizontal, despite jar tilt, by selecting the correct raised-line drawing given four choices. Low-vision subjects, with near perfect scores, performed significantly better than the other groups of subjects. While the late-blind and blindfolded sighted subjects performed slightly better than the congenitally blind participants, the difference between the late-blind and congenitally blind groups was nonsignificant. The performance of the congenitally blind subjects indicates that visual experience is not necessary for the development of an understanding that water level stays horizontal, given container tilt.

Purpose: The purpose of this study was to examine cases of patients with impingement syndrome secondary to an unfused, unstable, os acromiale., Type of Study: Retrospective case series., Materials and Methods: Twelve consecutive patients (13 shoulders) presented with impingement symptoms in the presence of an os acromiale. The os acromiale, at the meso-acromion level, was seen on standard radiographs. The patients were all treated conservatively with rotator cuff strengthening, stretching, anti-inflammatory medications, and steroid injections. All patients underwent an impingement test with lidocaine, resulting in complete relief of their pain. After failure of the conservative management, the 12 patients (13 shoulders) underwent an extended arthroscopic subacromial decompression. The goal of the modified arthroscopic acromioplasty was resection of adequate bone to remove the mobile anterior acromial tip. In general, this consisted of more bony resection than the typical arthroscopic acromioplasty. Postoperatively, the patients began a rehabilitation program emphasizing early range of motion followed by isolated free-weight rotator cuff strengthening exercises. Five shoulders had a partial-thickness tear of the rotator cuff. Four involved less than 50% of the thickness of the rotator cuff. These 4 partial-thickness tears underwent arthroscopic rotator cuff debridement. One partial-thickness tear was greater than 50% and repair was performed with a mini-open deltoid-splitting technique., Results: Results were evaluated using UCLA shoulder scoring. Preoperatively, the score averaged 17. The 3-month postoperative score was 27, and at 6 and 12 months, averaged 28. The final follow-up score averaged 31. There were 11 satisfactory results with UCLA scores >/=28. Two unsatisfactory results showed UCLA scores in the fair category. Full strength of the anterior deltoid and rotator cuff muscles was achieved in all patients by 6 months postoperatively as evaluated by manual muscle testing. Twelve of the 13 shoulders were rated by the patients as having a satisfactory result. All of the patients rated their cosmetic results as acceptable. There was no evidence of postoperative deltoid detachment. No patient developed pain at the pseudarthrosis point., Conclusions: Given the previously reported poor results with attempts at fusion of an unstable os acromiale and open complete excision of meso-acromial fragments, the authors conclude that an extended arthroscopic subacromial decompression results in a reasonable outcome for patients with impingement syndromes secondary to an unstable os acromiale.

In four experiments, reducing lenses were used to minify vision and generate intersensory size conflicts between vision and touch. Subjects made size judgments, using either visual matching or haptic matching. In visual matching, the subjects chose from a set of visible squares that progressively increased in size. In haptic matching, the subjects selected matches from an array of tangible wooden squares. In Experiment 1, it was found that neither sense dominated when subjects exposed to an intersensory discrepancy made their size estimates by using either visual matching or haptic matching. Size judgments were nearly indentical for conflict subjects making visual or haptic matches. Thus, matching modality did not matter in Experiment 1. In Experiment 2, it was found that subjects were influenced by the sight of their hands, which led to increases in the magnitude of their size judgments. Sight of the hands produced more accurate judgments, with subjects being better able to compensate for the illusory effects of the reducing lens. In two additional experiments, it was found that when more precise judgments were required and subjects had to generate their own size estimates, the response modality dominated. Thus, vision dominated in Experiment 3, where size judgments derived from viewing a metric ruler, whereas touch dominated in Experiment 4, where subjects made size estimates with a pincers posture of their hands. It is suggested that matching procedures are inadequate for assessing intersensory dominance relations. These results qualify the position (Hershberger & Misceo, 1996) that the modality of size estimates influences the resolution of intersensory conflicts. Only when required to self-generate more precise judgments did subjects rely on one sense, either vision or touch. Thus, task and attentional requirements influence dominance relations, and vision does not invariably prevail over touch.

A study is reported of gender differences in a haptic version of three Piagetian tests that assess understanding of Euclidian space. A raised-line drawing kit was used both for subject responses and for production of stimuli. To test understanding of the horizontal, subjects felt pictures of a jar at four tilts and were asked to draw the water line. Two methods were used to examine understanding of the vertical. First, subjects drew a hanging electrical cord and light bulb, attached to the ceiling of a bus, parked on hills of four different angles. Subsequently, subjects drew telephone poles (represented by a single line) on hills of four different angles. In the jar task, males and females showed comparable performance, both groups showing large errors. Judgments of the vertical were very similar for males and females in the bus task, but errors diminished considerably for both genders when subjects drew telephone poles on hills. It is suggested that better judgments of the vertical in the pole task probably derive from the use of body-centered spatial reference information.

Theory of tactile pictures argues that untrained blind subjects can recognize raised, outline pictures. It contends the blind person's knowledge of the shapes of common objects is like that of the sighted, and the blind person's pictorial abilities use the same principles as the sighted person's. To test this theory, blind children (aged 8-13) and blindfolded age-matched sighted children were asked to identify raised-line drawings of common objects. Their performances were correlated. In addition, the blind children identified more than sighted children exploring the pictures actively, but the same number of pictures as sighted children who were given passive, guided exploration. We argue blind and sighted children use the same principles to identify the pictures, but the blind have superior exploration skills. The differences in the effects of exploration skills on recognition scores are minimized when the sighted children are given guidance, since the sighted children then have efficient contact with the displays, and the performance of the sighted and the blind is then governed by the same principles, without one group benefitting from advantages in exploration skills.

The acute effects of a low dose of phencyclidine (PCP) and the delayed effects of a high dose of PCP on latent inhibition (LI) were assessed in a series of experiments using conditioned taste aversion paradigms. Each paradigm involved a preexposure phase in which water-deprived male rats were allowed access to either water (nonpreexposed; NPE) or 5% sucrose (preexposed; PE), followed by a conditioning phase in which animals were allowed access to sucrose and subsequently injected with the negative reinforcer lithium chloride, and a test phase in which animals were allowed access to both sucrose and water. LI was assessed by comparing the %-sucrose consumed in PE and NPE groups on the test day. The effects of low-dose PCP (2.5 mg/kg) were assessed by comparing LI in animals treated with vehicle or PCP 15 min prior to the onset of the preexposure and conditioning phases. A 4-day paradigm involved 2 days of preexposure followed by a day of conditioning and a test day. This paradigm produced comparable levels of LI in vehicle and PCP-treated animals. A 5-day extinction paradigm involved 2 days of preexposure followed by 2 days of conditioning and a test day. This paradigm abolished LI in vehicle and PCP-treated animals. A 3-day paradigm involved 1 day of preexposure followed by a day of conditioning and a test day. One day of preexposure induced a modified LI effect in both in vehicle and PCP-treated animals. The delayed effects of high dose PCP (8.6 mg/kg) were assessed by comparing LI in animals treated with vehicle or PCP 20 h prior to the onset of the preexposure and conditioning phases in the 4-day paradigm. PCP disrupted latent inhibition in this paradigm. The results are discussed in the context of their relevance to the ability for PCP to model schizophrenic symptomatology.

The "tragedy of the commons" metaphor helps explain why people overuse shared resources. However, the recent proliferation of intellectual property rights in biomedical research suggests a different tragedy, an "anticommons" in which people underuse scarce resources because too many owners can block each other. Privatization of biomedical research must be more carefully deployed to sustain both upstream research and downstream product development. Otherwise, more intellectual property rights may lead paradoxically to fewer useful products for improving human health.

We sought to clarify the causes of the tactual horizontal-vertical illusion, where vertical lines are overestimated as compared with horizontals in L and inverted-T figures. Experiment 1 did not use L or inverted-T figures, but examined continuous or bisected horizontal and vertical lines. It was expected that bisected lines would be perceived as shorter than continuous lines, as in the inverted-T figure in the horizontal-vertical illusion. Experiment 1 showed that the illusion could not be explained solely by bisection, since illusory effects were similar for continuous and bisected vertical and horizontal lines. Experiments 2 and 3 showed that the illusory effects were dependent upon stimulus size and scanning strategy. Overestimation of the vertical was minimal or absent for the smallest patterns, where it was proposed that stimuli were explored by finger movement, with flexion at the wrist. Larger stimuli induce whole-arm motions, and illusory effects were found in conditions requiring radial arm motion. The illusion was weakened or eliminated in Experiment 4 when subjects were forced to examine stimuli with finger-and-hand motion alone, that is, their elbows were kept down on the table surface, and they were prevented from making radial arm motions. Whole-arm motion damaged performance and induced perceptual error. The experiments support the hypothesis that overestimation of the vertical in the tactual horizontal-vertical illusion derives from radial scanning by the entire arm.

Four experiments examined the influence of categorical information and visual experience on the identification of tangible pictures, produced with a raised-line drawing kit. In Experiment 1, prior categorical information aided to accuracy and speed of picture identification. In a second experiment, categorical information helped subjects when given after the examination of each picture, but before any attempt at identification. The benefits of categorical information were also obtained in another group of subjects, when the superordinate categories were named at the start of the experiment. In a third experiment, a multiple-choice picture recognition task was used to eliminate the difficulty of naming from the picture-identification task. The multiple-choice data showed higher accuracy and shorter latencies when compared with identification tasks. A fourth experiment evaluated picture identification in blindfolded sighted, early, and late blind participants. Congenitally blind subjects showed lower performance than did the other groups, despite the availability of prior categorical information. The data were consistent with theories that assume that visual imagery aids tactual perception in naming raised line drawings. It was proposed that part of the difficulty in identification of raised line pictures may derive from problems in locating picture categories or names, and not merely in perception of the patterns.

In three experiments the production and interpretation of perspective drawings by blind and sighted subjects were examined. Blindfolded sighted, early-blind, and late-blind subjects first attempted to produce raised-line drawings of a surface at a number of angles-0 degree (panel horizontal), -22.5 degrees, -45 degrees, -67.5 degrees, and -90 degrees (vertical). Congenitally blind subjects did not show foreshortening in their naive raised-line drawings. However, the congenitally blind subjects were able to understand aspects of perspective, and performed as well as the blindfolded sighted and late-blind subjects in a subsequent multiple-choice task. Subjects in the multiple-choice task were required to match tangible perspective drawings to a slanted board. Although the three groups performed alike, both groups of blind subjects performed better than blindfolded sighted controls on judgments involving drawings of the vertical panel in the second experiment. In a final experiment, in which vision and touch were compared, sighted subjects were required to adjust the angle of the panel to match foreshortened, perspective drawings. This experiment yielded significantly better performance with vision than with touch, but only for drawings of the board at the vertical orientation. The results suggested that congenitally blind people may benefit from haptic exposure to raised-line configurations representing geometric perspective.

Subjects were exposed to a three-dimensional model of a house and were asked to draw it using a raised-line drawing kit. Independent groups of ten each of sighted controls, early-blind, and late-blind subjects were told to identify the vantage point of tangible pictures of the model, including side views, 'bird's-eye' views from above, and views involving linear perspective. The ease or difficulty of picture interpretation depended upon the nature of the tangible drawing, with much better performance being recorded for side views. Performance was poor for foreshortened 3/4 views. Early-blind subjects were particularly unlikely to recognize views from above. In a control experiment with blindfolded sighted subjects the influence of prior information was examined: some subjects were told that the drawings could consist of side view or bird's-eye, top view, or 3/4 view drawings. This experiment showed that performance can be greatly improved through prior information about the nature of the tangible pictures.

This study was an attempt to clarify the mechanisms responsible for the benefits of visual guidance in tactual braille recognition. Subjects touched +90 degrees tilted braille under normal room lighting, or with low lighting, with or without visual guidance. Both visual information about finger angle and spatial reference information were manipulated with stained glass and light-emitting diodes. The provision of visual information about finger angle alone was no help to braille recognition, and performance was low. Adding visual spatial reference information to vision of finger angle raised performance. However, recognition accuracy was also substantially improved by low lighting. The benefits of darkness for haptics did not generalize to the reading of upright, two-letter braille words. It was proposed that extraneous visual information may distract sighted subjects in haptic tasks that require mental rotation of visual images.

The haptic horizontal-vertical illusion was studied in two experiments. In Experiment 1, the illusion was relatively weak in sighted subjects and depended on stimulus size and the nature of the figure, that is, whether the pattern was an inverted-T or L shape. Experiment 2 compared early blind and late blind subjects. The illusion was present for an inverted-T figure but absent for an L figure in late blind subjects. However, the early blind subjects treated both the L and T figures as similar and showed the illusion to both. These results support the idea that visual experience may alter haptic judgments in sighted and late blind subjects.

Subjects in five experiments matched tangible braille against a visible matching code. In Experiment 1, braille recognition suffered when entire lines of braille characters were tilted in varying amounts from the upright. Experiment 2 showed that tilt lowered performance for tangible, large embossed letters, as well as for braille. However, recognition was better for print letters than it was for braille. In Experiment 3, subjects attempted to match the upright array against embossed braille that was left/right reversed, inverted up/down, or rotated +180 degrees. Performance was close to that for normal braille in the left/right reversal condition, and very low for the +180 degrees rotation group. These results on braille tilt in the "picture plane" may reflect difficulty in manipulating the tangible "image." Braille recognition performance was not lowered when the visible matching array was tilted -45 degrees or -90 degrees from the upright but the tangible stimuli were upright. In Experiment 4, recognition of left/right reversed braille that was physically horizontal (on the bottom of a shelf) was compared with that of braille left/right reversed due to its location on the back of a panel, in the vertical plane. Braille recognition accuracy was higher with braille located vertically. An additional experiment showed the beneficial effect of locating braille in the vertical, frontoparallel plane, obtained with +90 degree rotated braille. It is proposed that optimal tactual performance with tangible arrays might depend on touching position, and on the physical position of stimuli in space. Just as there are good and poor viewing positions, there may be optimal touching positions.(ABSTRACT TRUNCATED AT 250 WORDS)

An experiment placed vision and touch in conflict by the use of a mirror placed perpendicular to a letter display. The mirror induced a discrepancy in direction and form. Subjects touched the embossed tangible letters p, q, b, d, W, and M, while looking at them in a mirror, and were asked to identify the letters. The upright mirror produced a vertical inversion of the letters, and visual inversion of the direction of finger movement. Thus, subjects touched the letter p, but saw themselves touching the letter b in the mirror. There were large individual differences in reliance on the senses. The majority of the subjects depended on touch, and only one showed visual dominance. Others showed a compromise between the senses. The results were consistent with an attentional explanation of intersensory dominance.