Journal articles on the topic 'Visual field base (VFL)'
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Guijt, M. C., A. H. Zamanipoor Najafabadi, I. C. Notting, A. M. Pereira, M. J. T. Verstegen, N. R. Biermasz, W. R. van Furth, and K. M. J. A. Claessen. "Towards a pituitary apoplexy classification based on clinical presentation and patient journey." Endocrine 76, no. 1 (January 24, 2022): 132–41. http://dx.doi.org/10.1007/s12020-022-02983-3.
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Abstract Purpose The condition of pituitary apoplexia contains the clinical spectre from life-threatening emergency to asymptomatic self-limiting course, which partly determines diagnostic delay and management. Outcome evaluation of course and management of pituitary apoplexia is hampered by the diverse presentation of this condition and requires appraisal. This study aimed to describe the patient journey, clinical presentation, and management of various types of pituitary apoplexy in a new classification to facilitate future outcome evaluation and identify unmet needs in the care process. Methods A single-center retrospective patient chart study was conducted between 2005–2021 (N = 98). Outcome measures were clinical symptoms at first presentation in hospital, being headache, consciousness, visual acuity, visual field defects (VFD), ophthalmoplegia, nausea, vomiting, fever, and hypopituitarism and care process characteristics. Results Mean age was 47.6 ± 16.6 years (51.0% male). We describe their patient journey and identified three different types, differing in clinical presentation, in-hospital route, and final treatment, e.g., Acute (type A, 52%), Subacute (type B, 22.5%), and Non-acute (type C, 25.5%). Type A generally presents with acute onset headaches, VFD, or ophthalmoplegia emergency setting, with lowest mean visual acuity of both eyes and frequent hypocortisolism. Conclusions Pituitary apoplexy can be approached as a spectrum of disease with 3 main subtypes, with a different initial presentation, different in-hospital route resulting in different management. Acknowledging subtypes with particular needs for (emergency) referrals to Pituitary Tumors Center of Excellence (PTCOE) will serve patient care improvements, outcome evaluations and address areas for improvement.
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Ernest, Paul J. G., Jan S. A. G. Schouten, Henny J. M. Beckers, Fred Hendrikse, Martin H. Prins, and Carroll A. B. Webers. "The evidence base to select a method for assessing glaucomatous visual field progression." Acta Ophthalmologica 90, no. 2 (August 4, 2011): 101–8. http://dx.doi.org/10.1111/j.1755-3768.2011.02206.x.
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Alekseev, A. P., E. V. Goshin, N. S. Davydov, N. A. Ivliev, and A. V. Nikonorov. "Visual-inertial odometry algorithms on the base of thermal camera." Information Technology and Nanotechnology, no. 2416 (2019): 183–88. http://dx.doi.org/10.18287/1613-0073-2019-2416-183-188.
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A trajectory building based on a camera data is one of the most popular tasks in the field of machine vision. In particular, this task appears when it is necessary to navigate in the absence of signals from global navigation systems such as GLONASS and GPS. In this work, study of existing methods of visual odometry for the flight trajectory restoration by shooting an infrared camera of the thermal range were conducted. To improve the accuracy, it is proposed to use the data from inertial sensors. As a result, it is shown that the proposed solution allows to successfully solve the problem of trajectory reconstruction.
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Sharpe, James A. "Visual Dysfunction with Basal Skull Tumours." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 12, S4 (November 1985): 332–35. http://dx.doi.org/10.1017/s0317167100035472.
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ABSTRACT:Early detection of visual loss caused by tumours of the base of the skull is accomplished by systematic tests of the pregeniculate optic pathway. Even when central acuity is relatively preserved, a relative afferent pupillary defect and reduced color perception yield evidence of impaired optic nerve conduction. Although confrontation tests of the visual fields are useful screening techniques, unexplained symptoms should be pursued with static and kinetic perimetry. Patterns of optic nerve and chiasmal field loss and atrophy of the disc or retinal nerve fibers are imprecise guides to the location of basal skull tumours. Regardless of the pattern of visual field defect, unexplained progressive loss of vision demands intensive neuroradiologic study of the basal cisterns and skull.
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Fredes, Felipe, Gabriel Undurraga, Pablo Rojas, Felipe Constanzo, Carolina Lazcano, Jaime Pinto, and Thomas Schmidt. "Visual Outcomes after Endoscopic Pituitary Surgery in Patients Presenting with Preoperative Visual Deficits." Journal of Neurological Surgery Part B: Skull Base 78, no. 06 (July 19, 2017): 461–65. http://dx.doi.org/10.1055/s-0037-1604169.
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Introduction Pituitary adenomas represent 15% of primary brain tumors. Visual disturbance is a common clinical manifestation of these neoplasms due, among other factors, to local mass effect on the optic system. Objective To evaluate changes of the visual fields in patients undergoing endoscopic endonasal approach (EEA) for pituitary adenomas and to find predictive factors for successful visual field outcome. Material and Methods This is a cross-sectional study. A review was conducted of medical records of consecutive patients with tumors of the sellar region undergoing EEA between January 2008 and December 2012 at the Skull Base Unit of Guillermo Grant Benavente Hospital, University of Concepción, Concepción, Chile, and who had undergone pre- and postoperative visual field evaluation. Results A total of 35 patients, with a mean age of 50.2 years, fulfilled the inclusion criteria. All patients had objective visual field disturbances before the surgery. Following surgery, 25 patients (71.4%) had favorable outcomes, whereas 8 (22.8%) had no change and 2 (5.8%) had an unfavorable outcome. Complete tumor removal was associated with a better visual outcome than those obtained after a subtotal removal. Discussion The EEA for pituitary tumors is particularly effective for visual field disturbances, with reported improvement rates ranging from 50 to 90%. Our series show similar results, with a 71.4% improvement of visual field disturbances. Conclusion This study adds further evidence to the current belief that EEA for pituitary adenomas is a safe and effective technique to improve visual field alterations. Complete removal of the tumor during surgery seems to be a predictive factor for a good visual outcome.
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Bampoe, Joseph, Paul Ranalli, and Mark Bernstein. "Postoperative Reversal of Complete (Monocular) Blindness in Skull Base Meningioma: Case Report." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 30, no. 1 (February 2003): 72–74. http://dx.doi.org/10.1017/s0317167100002481.
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ABSTRACT:Background:Meningiomas of the anterior cranial fossa frequently present with impaired visual function. Recognition of this entity in the differential diagnosis of painless, progressive, and asymmetric optic neuropathy is important since reversal of visual loss is possible given timely surgical excision of the tumour.Methods:A 76-year-old man presented with no perception of light in his right eye and a reduced visual acuity of 20/60 in his left eye with a markedly constricted visual field. His visual deterioration had progressed over the previous three months and was not associated with headache. Ophthalmoscopy showed normal optic discs. MRI scanning showed a large frontal basal meningioma, which was subsequently resected.Results:The patient noticed an immediate improvement in his vision in his right eye. Visual acuity in his right eye improved to 20/50 at six weeks postoperatively and to 20/25 at five months, with corresponding improvement of the visual field.Conclusion:Complete monocular blindness due to tumour compressing or distorting the anterior visual pathways does not preclude recovery following timely decompressive surgery, especially when the appearance of the optic disc is normal.
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Holbrook, M. Cay. "Renewing and Refreshing Knowledge Base of the Field of Visual Impairment: A Call to Action." Journal of Visual Impairment & Blindness 109, no. 2 (March 2015): 159–62. http://dx.doi.org/10.1177/0145482x1510900213.
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Kiyofuji, Satoshi, Amanda M. Casabella, Christopher S. Graffeo, Avital Perry, James A. Garrity, and Michael J. Link. "Sphenoorbital meningioma: a unique skull base tumor. Surgical technique and results." Journal of Neurosurgery 133, no. 4 (October 2020): 1044–51. http://dx.doi.org/10.3171/2019.6.jns191158.
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OBJECTIVESphenoorbital meningioma (SOM) is a unique skull base tumor, characterized by infiltrative involvement and hyperostosis primarily of the lesser wing of sphenoid bone, with frequent involvement of the orbital compartment. SOM often manifests with proptosis and visual impairment. Surgical technique and outcome are highly variable among studies reported in the literature. The authors present a single-surgeon experience with SOM.METHODSA retrospective review of a prospectively maintained institutional database was performed. A blinded imaging review by 2 study team members was completed to confirm SOM, after which chart review was carried out to capture demographics and outcomes. All statistical testing was completed using JMP Pro version 14.1.0, with significance defined as p < 0.05.RESULTSForty-seven patients who underwent surgery between 2000 and 2017 were included. The median age at surgery was 47 years (range 36–70 years), 81% of patients were female, and the median follow-up was 43 months (range 0–175 months). All operations were performed via a frontotemporal craniotomy, orbitooptic osteotomy, and anterior clinoidectomy, with extensive resection of all involved bone and soft tissue. Preoperatively, proptosis was noted in 44 patients, 98% of whom improved. Twenty-eight patients (60%) had visual deficits before surgery, 21 (75%) of whom improved during follow-up. Visual field defect other than a central scotoma was the only prognostic factor for improvement in vision on multivariate analysis (p = 0.0062). Nine patients (19%) had recurrence or progression during follow-up.CONCLUSIONSSOM is a unique skull base tumor that needs careful planning to optimize outcome. Aggressive removal of involved bone and periorbita is crucial, and proptosis and visual field defect other than a central scotoma can improve after surgery.
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Slaboda, Jill C., Richard T. Lauer, and Emily A. Keshner. "Postural Responses of Adults With Cerebral Palsy to Combined Base of Support and Visual Field Rotation." IEEE Transactions on Neural Systems and Rehabilitation Engineering 21, no. 2 (March 2013): 218–24. http://dx.doi.org/10.1109/tnsre.2013.2246583.
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Streepey, Jefferson W., Robert V. Kenyon, and Emily A. Keshner. "Visual motion combined with base of support width reveals variable field dependency in healthy young adults." Experimental Brain Research 176, no. 1 (October 28, 2006): 182–87. http://dx.doi.org/10.1007/s00221-006-0677-2.
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Wang, Xiaoyu, Wang Zhao, Yongzhong Wang, Qin Zhao, Xuejie Yang, Kaixiang Su, and Dongxiao Gu. "Visual Analysis on Information Theory and Science of Complexity Approaches in Healthcare Research." Entropy 22, no. 1 (January 16, 2020): 109. http://dx.doi.org/10.3390/e22010109.
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In order to explore the knowledge base, research hotspot, development status, and future research direction of healthcare research based on information theory and complex science, a total of 3031 literature data samples from the core collection of Web of Science from 2003 to 2019 were selected for bibliometric analysis. HistCite, CiteSpace, Excel, and other analytical tools were used to deeply analyze and visualize the temporal distribution, spatial distribution, knowledge evolution, literature co-citation, and research hotspots of this field. This paper reveals the current development of healthcare research field based on information theory and science of complexity, analyzes and discusses the research hotspots and future development that trends in this field, and provides important knowledge support for researchers in this field for further relevant research.
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Budak, Vladimir P., and Julian B. Aizenberg. "The Light Field And The Scope Of Light Science." Light & Engineering, no. 01-2021 (February 2021): 4–10. http://dx.doi.org/10.33383/2020-080.
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For centuries, light has been produced to enable the human visual system to operate but, today, light is being used for an increasing number of non-visual, technical purposes. Examples include plant growth, remote sensing, electricity generation, and communication. This paper discusses the theoretical foundation of such technical applications of light and shows that it is completely identical to the fundamentals of lighting. The foundation is the theory of the light field, which is generated by the interaction of the radiation field with a quadratic (energy) receiver. Within its range of applicability, the theory of the light field is complete and closed. As a result, the light field provides a unified theoretical base for lighting systems and the technical application of light. This creates the basis for combining them into a single section of science and technology, which will ensure their effective development and application.
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Nogaj, Sławomir, Katarzyna Dubas, and Andrzej Michalski. "Efficacy of visual process improvement in patients with homonymous hemianopia." OphthaTherapy. Therapies in Ophthalmology 8, no. 1 (March 18, 2021): 26–30. http://dx.doi.org/10.24292/01.ot.300321.4.
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Homonymous hemianopia is a visual field defect following a stroke, tumor development, traumatic brain injury and other rare causes. Due to the damage to the visual system, lateral neglect occurs that induces difficulties with detecting objects on one side of the binocular visual field, which exposes patients to potential danger during daily activities, especially performed outside – in traffic. Different optical aids such as Fresnel prism have been developed to help those patients by increasing the perception of the affected hemifield. This prism correction can appear in various configurations, for instance: yoked prism, monocular and binocular sector prisms placed with a base to the affected side. The other option to deal with these patients is visual training based on stimulating the affected hemifield.
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Porojan, Sorin, Liliana Sandu, and Florin Topală. "Visual Evaluation of Cast Dental Alloys Welds Discontinuities in the Field of Fixed Prosthodontics." Advanced Materials Research 383-390 (November 2011): 4058–64. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.4058.
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It is essential for a weld to satisfy the requirements of certain standards in the field where it is applied. The aim of the study was to highlight the discontinuities which can appear in the joints achieved by laser and microplasma welding of base metal dental alloys used in fixed prosthodontics. All types of discontinuities which are visible from visual inspection were searched: inclusions, inadequate joint penetration, incomplete fusion, undercuts, overlaps, underfills. Recognizing the defects and discontinuities and their delimitation was essential in determining the weld quality. The obtained results were satisfactory for the purpose both for microplasma and laser welding. Using these methods, welds without defects, which meet minimum acceptable standards for each case, could be obtained.
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Skonnikov, P. N., and D. V. Trofimov. "PUPIL VISUAL TRACKING ALGORITHMS FOR AUTOMATED STATIC PERIMETRY SYSTEMS." International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIV-2/W1-2021 (April 15, 2021): 195–99. http://dx.doi.org/10.5194/isprs-archives-xliv-2-w1-2021-195-2021.
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Abstract. Some diseases, for instance, a glaucoma, cause visual field defects. For the timely diagnostics of such defects, various methods are used. One of the state-of-the-art diagnostic methods is automated static perimetry. The method of static perimetry consists in the light sensitivity determination in different parts of the visual field using stationary objects of variable luminosity. When scanning the visual field in this way, an important factor is the control of gaze fixation at the fixation point. The greatest accuracy in determining the gaze fixation position is achieved by the method of the pupil visual tracking using a video camera.In this paper, four groups of visual tracking algorithms are considered: segmentation-based methods, correlation methods, methods based on optical flow and on weighted average. An experimental comparison of these methods was carried out using the base of video recordings obtained in the automatic static perimetry apparatus. On these videos the ground truth tracks of pupil were marked. The comparison was conducted according to two criteria: center location error and tracking length. It is shown that only the weighted average method has an acceptable tracking length.
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Kennedy, Robert S., Kevin S. Berbaum, and Martin G. Smith. "Methods for Correlating Visual Scene Elements with Simulator Sickness Incidence." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 37, no. 18 (October 1993): 1252–56. http://dx.doi.org/10.1177/154193129303701811.
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Simulator sickness occurs in a large number of Army, Navy, and Marine Corps simulators, and is most prevalent in moving-base, rotary-wing devices which employ cathode ray tube (CRT) video displays as opposed to fixed-wing, dome-display trainers with no motion base. Based on data from a factor analysis of over 1000 Navy and Marine Corps pilot simulation exposures, a new scoring procedure was applied to two helicopter simulators with similar rates of simulator sickness incidence. Based on the factor analytic scoring key, the two simulators showed slightly different sickness profiles. Preliminary work was begun to record the visual scene by video frame-by-frame decomposition and automated scoring algorithms were developed. The findings are discussed from the standpoints of (1) recommendations for future design and use of simulators, and (2) the metric advantages and other merits of the “field experiment” methodology to address human factors problems with simulator sickness.
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Streepey, Jefferson W., Robert V. Kenyon, and Emily A. Keshner. "Field of view and base of support width influence postural responses to visual stimuli during quiet stance." Gait & Posture 25, no. 1 (January 2007): 49–55. http://dx.doi.org/10.1016/j.gaitpost.2005.12.013.
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Kurschel, S., V. Gellner, G. Clarici, H. Braun, H. Stammberger, and M. Mokry. "Endoscopic rhino-neurosurgical approach for non-adenomatous sellar and skull base lesions." Rhinology journal 49, no. 1 (March 1, 2011): 64–73. http://dx.doi.org/10.4193/rhino10.046.
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OBJECTIVE: Since endoscopic endonasal transsphenoidal surgery requires skills of both neurosurgeons and otorhinolaryngologists, and the nose is the primary corridor of approach, we favour the term `endoscopic rhino-neurosurgery` and report on our interdisciplinary experience treating non-adenomatous lesions with skull base extension. METHODS: Between 2004 and 2009, 58 patients with 21 different disease patterns underwent endoscopic rhino-neurosurgical procedures. Mean age was 39.9 years, 50% were female. Seven had undergone prior surgery. Clinically, 34.5% presented with visual field deficits and with nerve palsies. Preoperatively, 62.1% showed a normal pituitary function. RESULTS: Mean follow-up was 13.1 months. The surgical goal depended on type of lesion; the intended extent of resection was achieved in 81%. Recovery from visual field deficits occurred in 80%. Neither deteriorated nor new cranial nerve palsies were observed. A normal endocrinological function could be maintained in 94.4%. Permanent diabetes insipidus occurred in 7 patients. Surgical complications included cerebrospinal fluid (CSF) leaks in 6 patients and meningitis in 4. All complications were managed successfully. There was no surgery-related mortality. CONCLUSION: The endoscopic rhino-neurosurgical approach is applicable for a wide variety of lesions comprising sella and skull base. As our data prove, this technique can be performed with satisfying results in non-adenomatous lesions as well.
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Zhou, Xixuan, Liao Yang, Weisheng Wang, and Baili Chen. "UAV Data as an Alternative to Field Sampling to Monitor Vineyards Using Machine Learning Based on UAV/Sentinel-2 Data Fusion." Remote Sensing 13, no. 3 (January 28, 2021): 457. http://dx.doi.org/10.3390/rs13030457.
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Pests and diseases affect the yield and quality of grapes directly and engender noteworthy economic losses. Diagnosing “lesions” on vines as soon as possible and dynamically monitoring symptoms caused by pests and diseases at a larger scale are essential to pest control. This study has appraised the capabilities of high-resolution unmanned aerial vehicle (UAV) data as an alternative to manual field sampling to obtain sampling canopy sets and to supplement satellite-based monitoring using machine learning models including partial least squared regression (PLSR), support vector regression (SVR), random forest regression (RFR), and extreme learning regression (ELR) with a new activation function. UAV data were acquired from two flights in Turpan to determine disease severity (DS) and disease incidence (DI) and compared with field visual assessments. The UAV-derived canopy structure including canopy height (CH) and vegetation fraction cover (VFC), as well as satellite-based spectral features calculated from Sentinel-2A/B data were analyzed to evaluate the potential of UAV data to replace manual sampling data and predict DI. It was found that SVR slightly outperformed the other methods with a root mean square error (RMSE) of 1.89%. Moreover, the combination of canopy structure (CS) and vegetation index (VIs) improved prediction accuracy compared with single-type features (RMSEcs of 2.86% and RMSEVIs of 1.93%). This study tested the ability of UAV sampling to replace manual sampling on a large scale and introduced opportunities and challenges of fusing different features to monitor vineyards using machine learning. Within this framework, disease incidence can be estimated efficiently and accurately for larger area monitoring operation.
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Liu, Han-Chin. "Investigating the Impact of Cognitive Style on Multimedia Learners’ Understanding and Visual Search Patterns: An Eye-Tracking Approach." Journal of Educational Computing Research 55, no. 8 (March 19, 2017): 1053–68. http://dx.doi.org/10.1177/0735633117697020.
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Multimedia students’ dependence on information from the outside world can have an impact on their ability to identify and locate information from multiple resources in learning environments and thereby affect the construction of mental models. Field dependence-independence has been used to assess the ability to extract essential information from the environment. This study utilized eye-tracking technology to explore whether field-dependent and field-independent (FI) learners differed in their visual searching efficiency and multimedia learning performance. The FI learners outperformed field-dependent learners in posttest indices. In addition, FI learners were better able to identify visual cues and demonstrated efficient visual search patterns when learning using different information formats. The research findings echoed previous findings: The dependence on information in the context of learning can affect learners’ visual search efficiency and learning performance. The findings of this study suggest that adaptable learning environments that provide a rich variety of media may benefit learners with different levels of information-dependence. Applying eye-tracking technology enabled blueprints to be created pertaining to the learners’ information processing. However, additional research techniques, such as think-aloud exercises, would enable deeper understanding of how learners construct mental models of a knowledge base in a multimedia learning environment.
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Alvarez Berastegui, G. Rene, Shaan M. Raza, Vijay K. Anand, and Theodore H. Schwartz. "Endonasal endoscopic transsphenoidal chiasmapexy using a clival cranial base cranioplasty for visual loss from massive empty sella following macroprolactinoma treatment with bromocriptine: case report." Journal of Neurosurgery 124, no. 4 (April 2016): 1025–31. http://dx.doi.org/10.3171/2015.2.jns142015.
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Visual deterioration after dopamine-agonist treatment of prolactinomas associated with empty sella syndrome and secondary optic apparatus traction is a rare event. Chiasmapexy has been described as a viable treatment option, although few cases exist in the literature. Here, a novel endonasal endoscopic approach to chiasmapexy is described and its efficacy is demonstrated in a case report. A 55-year-old female patient with a history of a giant prolactinoma and 14 years of treatment using dopaminergic agonist therapy presented to our institution with a 1-month history of visual changes. Neuroophthalmological examination confirmed severe bitemporal field defects, and MRI revealed a large empty sella with downward optic chiasmal herniation. Endoscopic endonasal chiasmapexy was performed by elevating the chiasm with lumbar drainage and filling the clival and sellar defect with an extradural liquid (HydroSet; a cranioplasty bone cement), and a piece of AlloDerm was used to cover and cushion the chiasm. Postoperative imaging demonstrated successful anatomical elevation of the optic apparatus, and the patient showed functional improvement in the visual field at 3 months postoperatively. Although rare, massive empty sellar and chiasmal descent from macroadenoma treatment can result in progressive visual loss. Here, a novel technique of endonasal endoscopic extradural cranioplasty aided by lumbar drainage is reported, which appears to be an effective technique for stabilizing and possibly reversing anatomical and visual deterioration.
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Martínez-de Dios, J. Ramiro, Jorge C. André, João C. Gonçalves, Begoña Ch Arrue, Aníbal Ollero, and Domingos X. Viegas. "Laboratory fire spread analysis using visual and infrared images." International Journal of Wildland Fire 15, no. 2 (2006): 179. http://dx.doi.org/10.1071/wf05004.
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This paper presents an experimental method using computer-based image processing techniques of visual and infrared movies of a propagating fire front, taken from one or more cameras, to supply the time evolutions of the fire front shape and position, flame inclination angle, height, and base width. As secondary outputs, it also provides the fire front rate of spread and a 3D graphical model of the fire front that can be rendered from any virtual view. The method is automatic and non-intrusive, has space–time resolution close to continuum and can be run in real-time or deferred modes. It is demonstrated in simple laboratory experiments in beds of pine needles set upon an inclinable burn table, with point and linear ignitions, but can be extended to open field situations.
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Esterman, Michael, Regina Mcglinchey-Berroth, Michael P. Alexander, and William Milberg. "Triangular backgrounds shift line bisection performance in hemispatial neglect: The critical point." Journal of the International Neuropsychological Society 8, no. 5 (July 2002): 721–26. http://dx.doi.org/10.1017/s1355617702801369.
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AbstractIsosceles triangular backgrounds influence line bisection performance in normal control participants and patients with hemispatial neglect. When the triangles are oriented asymmetrically with the vertex in 1 visual field, and the base in the other, the perceived midpoint of horizontal lines within the triangle is shifted towards the base, and away from the vertex. The current study examines this illusion further by systematically varying the extent of the triangle presented. With only fragments of the triangle in the background of the line, the vertex is the critical component driving the illusory shift in perceived midpoint. Patients with neglect and controls are equally sensitive to the illusion. Similar geometric illusions that are also intact in neglect, along with these results, suggest that preattentive, implicit visual processing is preserved in neglect and drives these illusions.
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Tritschler, John K., John C. O'Connor, James A. Pritchard, and Ryan Wallace. "Exploratory Investigation into Rotorcraft Pilot Strategy and Visual Cueing Effects in the Shipboard Environment." Journal of the American Helicopter Society 65, no. 2 (April 1, 2020): 1–13. http://dx.doi.org/10.4050/jahs.65.022003.
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The present work reports the results of a research investigation into the handling qualities of a helicopter conducting a ship approach and landing task. The investigation was performed via fixed-base, pilot-in-the-loop flight simulation and included six test pilots with extensive operational and test experience in the shipboard environment. Representative approach/landing tasks were flown with three different response types to a field landing zone and to multiple spots on an amphibious assault ship. The ship was stationary, and there was no simulated ship airwake, so the fundamental differences between the field and ship approaches were limited to visual cueing. Traditional subjective handling qualities ratings were supplemented with multiple other analysis techniques, including pilot eye-tracking analysis and pilot control activity analysis. The results show that there are fundamental differences in the pilot gaze patterns between field and ship approaches that are caused by the different cueing environments. Additionally, subjective assessments indicated that pilots preferred higher degrees of aircraft stabilization in the shipboard environment than in the field environment, though there were not significant differences between pilot control techniques in these environments for a given aircraft response type.
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Schmidt, Richard H., Lisa A. Rietz, Bhupendra C. K. Patel, Anne G. Osborne, David Pratt, and Kathleen B. Digre. "Compressive optic neuropathy caused by renal osteodystrophy." Journal of Neurosurgery 95, no. 4 (October 2001): 704–9. http://dx.doi.org/10.3171/jns.2001.95.4.0704.
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✓ Compressive optic neuropathy with acute or chronic vision loss has been associated with various skull base tumors, aneurysms, Graves disease, trauma, and, less commonly, fibrous dysplasia and osteopetrosis. The authors present a case of acute visual deterioration in a 25-year-old woman who had massive calvarial hypertrophy with optic canal stenosis secondary to renal osteodystrophy (uremic leontiasis ossea [ULO]: bighead disease). Significant visual field restoration was achieved with high-dose corticosteroids followed by optic nerve decompression. This is the first case report of cranial neuropathy associated with ULO.
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Li, Zhenxin, Xuande Zhang, Long Xu, and Weiqiang Zhang. "Fast and Robust Visual Tracking with Few-Iteration Meta-Learning." Sensors 22, no. 15 (August 4, 2022): 5826. http://dx.doi.org/10.3390/s22155826.
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Visual object tracking has been a major research topic in the field of computer vision for many years. Object tracking aims to identify and localize objects of interest in subsequent frames, given the bounding box of the first frame. In addition, the object-tracking algorithms are also required to have robustness and real-time performance. These requirements create some unique challenges, which can easily become overfitting if given a very small training dataset of objects during offline training. On the other hand, if there are too many iterations in the model-optimization process during offline training or in the model-update process during online tracking, it will cause the problem of poor real-time performance. We address these problems by introducing a meta-learning method based on fast optimization. Our proposed tracking architecture mainly contains two parts, one is the base learner and the other is the meta learner. The base learner is primarily a target and background classifier, in addition, there is an object bounding box prediction regression network. The primary goal of a meta learner based on the transformer is to learn the representations used by the classifier. The accuracy of our proposed algorithm on OTB2015 and LaSOT is 0.930 and 0.688, respectively. Moreover, it performs well on VOT2018 and GOT-10k datasets. Combined with the comparative experiments on real-time performance, our algorithm is fast and robust.
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Duchon, Andrew P., and William H. Warren. "A Visual Equalization Strategy for Locomotor Control: Of Honeybees, Robots, and Humans." Psychological Science 13, no. 3 (May 2002): 272–78. http://dx.doi.org/10.1111/1467-9280.00450.
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Honeybees fly down the center of a corridor by equating the speed of optic flow in the lateral field of the two eyes. This flow-equalization strategy has been successfully implemented in mobile robots to guide behavior in cluttered environments. We investigated whether humans use a similar strategy to steer down a corridor, and determined the relative contributions of equating the speed of flow (.27), the splay angles of base lines (.62), and the visual angles of texture on the left and right walls (.03) to steering behavior. A generalized equalization strategy based on the weighted linear combination of these variables closely models human behavior, providing robust visual control.
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Tang, Xi Ya, Chen Zhong, and Lin Wu. "The Research of Column Base Culture in Chinese Traditional Architectures." Advanced Materials Research 1065-1069 (December 2014): 2661–68. http://dx.doi.org/10.4028/www.scientific.net/amr.1065-1069.2661.
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As the traditional construction of stress components, column bases became a typical representative of the perfect unity of Chinese traditional architectural structure component and art component with its rich shapes and vivid carving. For thousands of years, column bases bearing the essence of Chinese traditional culture and religion in the form of objects, and it also showing the exquisite building techniques of Chinese architects in visual form of art. The evolution of pillar bases is not only the epitome of the development of Chinese traditional architectural decorative art, but also the indispensable bright spots of Chinese traditional architectural art. The column base, commonly known as “Sang Pan” or “column base stock”, which is the foundation under the column. It is a significant component under the column in wooden structure which could increase the stressed area, prevent moisture, keep smoothing as well as prevent the column from moving or sinking and strengthen the pressure. The column base was come into being for demand of enginery in ancient architechtures and had experienced the progress from hiding underground to cropping out. The changes of the column base’s position had made visual changes to the single straight column, with the function of load-bearing and decoration at the same time. For thousands of years, column bases bearing the essence of Chinese traditional culture and religion in the form of objects, and it also showing the exquisite building techniques of Chinese architects in visual form of art. The evolution of pillar bases is not only the epitome of the development of Chinese traditional architectural decorative art, but also the indispensable bright spots of Chinese traditional architectural art. The column base gradually become a perfect field where artists could display their skills and it gave artisans much possibility in its shape and decoration. 【１】Therefore, the column base has become the focal point of traditional architechture culture scholars because its decorative function is more than structural demand.
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Du, Haiming. "The Promotion of Regional Cultural Resources and the Integration of Visual Art Education—Take Haihunhou Culture as an Example." Learning & Education 9, no. 2 (November 10, 2020): 94. http://dx.doi.org/10.18282/l-e.v9i2.1412.
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In the development of the big data era, major changes are taking place in many fields in the world, and the field of visual art education is no exception. Breaking through the old style of aesthetic education, transforming from art education to visual art education, and achieving interdisciplinary teaching is a major challenge and opportunity for art educators. This article takes Jiangxi’s regional culture—Haihunhou culture as the research base, integrates museum research, network interactive experience, local teaching materials and other methods to conduct junior high school art teaching, making full use of the rich cultural and social resources at present, There is a new breakthrough in art classroom education, which more representatively reflects the inheritance, innovation and comprehensiveness of the integration of regional cultural resources and visual art education.
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Chávez, Ricardo Omar, Hugo Jair Escalante, Manuel Montes-y-Gómez, and Luis Enrique Sucar. "Multimodal Markov Random Field for Image Reranking Based on Relevance Feedback." ISRN Machine Vision 2013 (February 11, 2013): 1–16. http://dx.doi.org/10.1155/2013/428746.
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This paper introduces a multimodal approach for reranking of image retrieval results based on relevance feedback. We consider the problem of reordering the ranked list of images returned by an image retrieval system, in such a way that relevant images to a query are moved to the first positions of the list. We propose a Markov random field (MRF) model that aims at classifying the images in the initial retrieval-result list as relevant or irrelevant; the output of the MRF is used to generate a new list of ranked images. The MRF takes into account (1) the rank information provided by the initial retrieval system, (2) similarities among images in the list, and (3) relevance feedback information. Hence, the problem of image reranking is reduced to that of minimizing an energy function that represents a trade-off between image relevance and interimage similarity. The proposed MRF is a multimodal as it can take advantage of both visual and textual information by which images are described with. We report experimental results in the IAPR TC12 collection using visual and textual features to represent images. Experimental results show that our method is able to improve the ranking provided by the base retrieval system. Also, the multimodal MRF outperforms unimodal (i.e., either text-based or image-based) MRFs that we have developed in previous work. Furthermore, the proposed MRF outperforms baseline multimodal methods that combine information from unimodal MRFs.
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Alkherayf, F., D. Houlden, C. Turgeon, C. Agbi, A. Lamothe, and S. Kilty. "P.008 Anterior skull base surgery future: intraoperative flash visual evoked potentials a novel technique to lessen intraoperative optic nerves and chiasmal injury." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 44, S2 (June 2017): S16. http://dx.doi.org/10.1017/cjn.2017.93.
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Background: Optic nerve/chiasmal injury is a devastating outcome that may happen during endoscopic surgery. Additionally, one of the goals of endoscopic skull-base surgery is visual improvement, currently there is limited ability of intraoperative visual pathway monitoring. We examine a novel technique using continuous flash visual evoked potentials (FVEPs). Methods: Eyes were stimulated by light stimulators (3 LEDs on each side, 640 nm peak wavelength, 10 ms pulse width, 3000 mCd of luminous intensity). Uniform illumination was placed over eyelids. Recording electrodes were placed at Oz-Fz. The filter cuts were ≤5 Hz and 100 Hz with amplifier gain 20,000 or 50,000. EEG was recorded. Recordings were correlated to pre and post operative VFs and acuity. Droop in the FVEP was examined in relation to intraoprative events. Results: Thirty patients had FVEPs in addition to other neurophysiologic monitoring. Patients demographic data, co-morbidities, diagnosis, surgical approach, length of surgery, MAP, and blood loss during surgery were recorded. All patients’ visual acuity and field deficits were evaluated by neuro-opthalmologist before their surgery and within 30 days after surgery. Conclusions: FVEP is reproducible throughout surgery and can predict the post surgical outcome. Additionally, we found that FVEP is transiently affected by different stages of surgery. Also boluses of propofol and electrocautery can artificially affect FVEP.
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Song, Lin, Huixuan Zhao, Zongfang Ma, and Qi Song. "A new method of construction waste classification based on two-level fusion." PLOS ONE 17, no. 12 (December 27, 2022): e0279472. http://dx.doi.org/10.1371/journal.pone.0279472.
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The automatic sorting of construction waste (CW) is an essential procedure in the field of CW recycling due to its remarkable efficiency and safety. The classification of CW is the primary task that guides automatic and precise sorting. In our work, a new method of CW classification based on two-level fusion is proposed to promote classification performance. First, statistical histograms are used to obtain global hue information and local oriented gradients, which are called the hue histogram (HH) and histogram of oriented gradients (HOG), respectively. To fuse these visual features, a bag-of-visual-words (BoVW) method is applied to code HOG descriptors in a CW image as a vector, and this process is named B-HOG. Then, based on feature-level fusion, we define a new feature to combine HH and B-HOG, which represent the global and local visual characteristics of an object in a CW image. Furthermore, two base classifiers are used to learn the information from the color feature space and the new feature space. Based on decision-level fusion, we propose a joint decision-making model to combine the decisions from the two base classifiers for the final classification result. Finally, to verify the performance of the proposed method, we collect five types of CW images as the experimental data set and use these images to conduct experiments on three different base classifiers. Moreover, we compare this method with other extant methods. The results demonstrate that our method is effective and feasible.
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Uchida, Kazunori, Masafumi Takematsu, Jun-Hyuck Lee, and Junichi Honda. "Parameter Estimation for Propagation along Random Rough Surface by Using Line of Sight Data." Mobile Information Systems 10, no. 3 (2014): 307–19. http://dx.doi.org/10.1155/2014/172910.
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This paper is concerned with a numerical procedure to estimate two parameters, amplitude modification factor α and propagation order of distance β, for electromagnetic (EM) propagation in complicated natural environments such as random rough surface (RRS). These two parameters are key parameters when we simulate field distributions along various types of RRS based on 1-ray model. We assume that the former parameter α can be evaluated by the visual planar angles of illuminated lines in case of 1D RRS and by the visual solid angles of illuminated planes in case of 2D RRS. We also assume that the latter parameter β can be estimated not only by base station (BS) antenna height, similar to Okumura-Hata model simulating EM propagation in urban and suburban areas, but also by mobile station (MS) antenna height. In order to demonstrate validity of the proposed parameter estimation, we compare the numerical field distributions obtained by the 1-ray model using estimated two parameters with those computed by discrete ray tracing method (DRTM) which is an effective EM field solver. It is shown that both numerical results are in good agreement.
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Mauledoux, Mauricio M., Carlos Hernandez, Crhistian C. G. Segura, and Oscar F. Aviles. "Object Tracking System Based on Artificial Vision Algorithms." Applied Mechanics and Materials 713-715 (January 2015): 420–23. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.420.
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This document describes the architecture of a tracking system with two degrees of freedom (pan and tilt), endowed with artificial vision to follow the path of a moving object. The mechanism with a fixed base was designed to cover lateral and vertical ranges of movement, similar to the visual field in humans, limiting its depth by the resolution of the camera. The object that defines the motion path presents color uniformity across its surface, becoming the main feature in which the recognition and tracking algorithm were based. The tracking is performed by reducing the error between the object position and the reference axis of the camera. Several tests were carried out to evaluate the control and visual systems and to illustrate the behavior of the proposed methods.
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Goulard, Roman, Anna Verbe, Jean-Louis Vercher, and Stéphane Viollet. "Role of the light source position in freely falling hoverflies' stabilization performances." Biology Letters 14, no. 5 (May 2018): 20180051. http://dx.doi.org/10.1098/rsbl.2018.0051.
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The stabilization of plummeting hoverflies was filmed and analysed in terms of their wingbeat initiation times as well as the crash and stabilization rates. The flies experienced near-weightlessness for a period of time that depended on their ability to counteract the free fall by triggering their wingbeats. In this paradigm, hoverflies' flight stabilization strategies were investigated here for the first time under two different positions of the light source (overhead and bottom lighting). The crash rates were higher in bottom lighting conditions than with top lighting. In addition, adding a texture to the walls reduced the crash rates only in the overhead lighting condition. The position of the lighting also significantly affected both the stabilization rates and the time taken by the flies to stabilize, which decreased and increased under bottom lighting conditions, respectively, whereas textured walls increased the stabilization rates under both lighting conditions. These results support the idea that flies may mainly base their flight control strategy on visual cues and particularly that the light distribution in the visual field may provide reliable, efficient cues for estimating their orientation with respect to an allocentric reference frame. In addition, the finding that the hoverflies' optic flow-based motion detection ability is affected by the position of the light source in their visual field suggests the occurrence of interactions between movement perception and this visual vertical perception process.
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Smith, Sullivan, Elliott D. Kozin, Vivek V. Kanumuri, Samuel R. Barber, Douglas Backous, João Flávio Nogueira, and Daniel J. Lee. "Initial Experience with 3-Dimensional Exoscope-Assisted Transmastoid and Lateral Skull Base Surgery." Otolaryngology–Head and Neck Surgery 160, no. 2 (January 1, 2019): 364–67. http://dx.doi.org/10.1177/0194599818816965.
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Extracorporeal video microscopes, or “exoscopes,” provide high-definition views of the operative field and are alternatives to the operating microscope or loupes for large-corridor surgical approaches. In this proof-of-concept study, we aim to determine the feasibility of 3-dimensional exoscopes as alternatives to operating microscopes in otology and neurotology, espeically in conjunction with endoscopes. Eleven consecutive cases were performed using 3-dimensional exoscopes in place of, or as adjuncts to, the operating microscope. The exoscope was the sole visualization tool in 7 cases, with 4 including the use of an endoscope or microscope. There were no perioperative complications. Potential subjective advantages include superior ergonomics, compact size, and an equal visual experience for surgeons and observers. Limitations include low lighting in small surgical corridors and pixilation at high magnification. Exoscopes are potentially viable alternatives to the microscope in otologic and neurotologic surgery.
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Visirov, Yu V., and A. A. Prusakov. "The generality and diff erence in verifi cation schemes for the main condition of the level." Geodesy and Cartography 936, no. 6 (July 20, 2018): 9–13. http://dx.doi.org/10.22389/0016-7126-2018-936-6-9-13.
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The causes of the violating horizontal positioning of the vision axis as the main geometric leveling condition were studied. The importance of this condition at leveling forward performed as the main method of altitude measurements for topographic and geodetic engineering works was particularly emphasized. When analyzing the ways of calibrating the main position, the authors highlighted the general regulations for different methods of determining the calibration base and mirror rotation of the tested level to the differences in visualization the visual scale readings depending on the length of shoulders of the upcoming leveling process. The obligatory required return of testing to initial altitude of calibration base creates a closed loop of heights that enables to define the correction of horizontal sight axis and the difference between the inequality sums of rear and front shoulders. For performing field works, a new scheme of calibration the main position of level with its offset from alignment calibration base is offered.
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Dorot, Ruth. "Visual Dignity in Art." Journal of Education Culture and Society 11, no. 1 (June 27, 2020): 241–54. http://dx.doi.org/10.15503/jecs2020.1.241.254.
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Aim. The aim of this article is to deal with visual dignity in the field of western art throughout the ages as it seeks to present the artistic and design devices employed by artists in order to compose and convey this aura of dignity. Moreover, it addresses the ways in which they create various kinds of atmosphere of respect and dignity felt by the observer regarding the topic and object of the painting or sculpture.
Methods. In order to achieve this aim, the article examines seven masterpieces which explore the visual representations of various perceptions of dignity and their implications. Among the elements affecting the creation of dignity in the visual domain one finds: an impressive or majestic appearance, noblesse, self-esteem, pride, self-confidence, inner strength, authoritativeness and charisma. At times, the respectful treatment of the figures is clear as soon as one views the work, but at others it is implied in the interpretation given to it.
It is not this article's intention to discuss the different perceptions or expressions of human dignity, historically, theologically, politically, psychologically, nationally or socially, but to present them artistically as they are the innate right of people to be appreciated, treated with courtesy and met with ethical behavior.
Results and conclusion. The research done in order to reach a conclusion confirming or contradicting the premises at its base, resulted in a mosaic of situations in which human dignity is reflected. The range of possibilities at the artists’ disposal for creating this value is diverse and includes: composition, use of color, mimesis, embellishment, disfigurement or distortion of reality.
The pieces examined present: a military commander at the moment of his foe's surrender; an author monumentally impressive, man of vision and power and of grand dimensions, rising up from a stone plinth; a stern-faced, disfigured dwarf considered a ‘curiosity’, seated on the ground; a family of farmers living an impoverished and meager life; and a Jesus-like mysterious intellectual and Moses the prophet. All these together at first glance appear to be a strange collection of works, in which the common denominator is unclear or seemingly absent. However, this diverse group is included in the article because of the aura of dignity the figures command or convey. At times, the respectful treatment of the figures is clear as soon as one views the work, but at others it is implied in the interpretation given to it.
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Yano, Shigetoshi, Fumihiro Hiraoka, Hiroya Morita, Hiroto Kawano, Takuto Kuwajima, Shin-ichiro Yoshida, Yoshiaki Hama, et al. "Usefulness of endoscope-assisted surgery under exoscopic view in skull base surgery: A technical note." Surgical Neurology International 13 (February 11, 2022): 30. http://dx.doi.org/10.25259/sni_965_2021.
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Background: The use of the exoscope has been increasing in the field of neurosurgery, as it can set the visual axis freely, enabling the surgeon to operate in a comfortable posture. Although endoscope-assisted surgery for compensation of insufficient surgical field is useful under the microscope, we report that using an endoscope in exoscopic surgery is safer and more useful. Methods: The exoscope used was ORBEYE. All surgical procedures were performed exoscopically from the beginning of the surgery. When endoscopic observation was required during the operation, the endoscope was inserted under observation by an exoscope. The exoscopic screen was 4K-3D and endoscopic screen was 4K-2D, the operation was performed while observing both screens at the same time. The endoscope was held manually or by a mechanical holder. Results: Twenty-two cases, including 14 requiring microvascular decompression (MVD) and eight requiring tumor removal, were performed by endoscopic-assisted exoscopic surgery. The endoscope could be inserted safely because its relationship with the surrounding structure could be observed under the exoscope, and the operator could observe both screens without moving the head. Fourteen of 22 patients required additional endoscopic treatment. Satisfactory two-handed operation was performed in 13 cases. Symptomatology disappeared in all cases of MVD, and sufficient tumor resection was achieved. Conclusion: Exoscopic surgery provides excellent surgical view that is not inferior to conventional microsurgery. As a large space can be secured between the scope and the surgical field, it is safer and easier to manipulate the endoscope under the exoscope.
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Dehdashti, Amir R. "Ophthalmic artery aneurysm treated by surgical clipping and balloon-assisted temporary carotid occlusion." Neurosurgical Focus 39, videosuppl1 (July 2015): V3. http://dx.doi.org/10.3171/2015.7.focusvid.14570.
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A 29-year-old woman is diagnosed with a large broad-base right ophthalmic artery aneurysm. Despite an intact visual field, she complained of mild right visual blurriness. Between endovascular and surgical treatments, surgery was favored due to her young age. It was decided to perform the surgery with simultaneous endovascular temporary carotid balloon occlusion. A right pterional craniotomy and intradural anterior clinoidectomy were performed, the balloon was positioned in the petrous carotid, and the distal durai ring was opened exposing the proximal neck. Under temporary proximal carotid balloon occlusion and distal carotid clip occlusion, the aneurysm was fully dissected and clipped. Intraoperative angiogram confirmed complete aneurysm occlusion and patency of the ophthalmic artery. The patient's neurological exam remained unchanged.The video can be found here: http://youtu.be/BIQKTl9bDqA.
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Yahya, Salah I. "The Use of Camouflaged Cell Phone Towers for a Quality Urban Environment." UKH Journal of Science and Engineering 3, no. 1 (May 22, 2019): 29–34. http://dx.doi.org/10.25079/ukhjse.v3n1y2019.pp29-34.
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The widespread use of cell phones has led to cell phone towers being located in many communities. These towers, also called base stations, incorporate electronic equipment and antennas that receive and transmit radiofrequency signals. Along with the towers, used for TV and line of sight microwave communication, the proliferation of these base stations is having a detrimental effect on urban esthetics. It is highly recommended for developing urban areas to consider the problem of these unsightly towers as a form of visual pollution, which increases in parallel with the rise of human population density, and also, the possible electromagnetic field (EMF) hazard due to the existence of the cell phone towers in the residential areas. This paper presents the feasibility of using camouflaged cell phone towers to improve the quality of the urban environment. Cell phone towers disguised as trees might address the visual pollution, while, at the same time, might also mitigate the possible EMF hazard by installing these disguised towers in free spaces, rather than on the roof of buildings, schools, hospitals, etc. The feasibility of implementing such a scenario for a quality urban environment in Koya city is discussed.
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Wierzbowska, Joanna, Arkadiusz Zegadło, Michał Patyk, and Marek Rękas. "Spheno-Orbital Meningioma and Vision Impairment—Case Report and Review of the Literature." Journal of Clinical Medicine 12, no. 1 (December 22, 2022): 74. http://dx.doi.org/10.3390/jcm12010074.
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(1) Background: Spheno-orbital meningioma (SOM) is a very rare subtype of meningioma which arises from the sphenoid ridge with an orbital extension. It exhibits intraosseous tumor growth with hyperostosis and a widespread soft-tissue growth at the dura. The intra-orbital invasion results in painless proptosis and slowly progressing visual impairment. (2) Methods: We present a case of a 46-year-old woman with SOM and compressive optic nerve neuropathy related to it. Her corrected distance visual acuity (CDVA) was decreased to 20/100, she had extensive visual field (VF) scotoma, dyschromatopsia, impaired pattern-reversal visual-evoked potential (PVEP), and decreased thicknesses of the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC), measured with the swept-source optical coherence tomography (SS-OCT), and a pale optic nerve disc in her left eye. Brain CT and MRI showed a lesion at the base of the anterior cranial fossa, involving the sphenoid wing and orbit. Pterional craniotomy and a partial removal of the tumor at the base of the skull and in the left orbit with the resection of the lesional dura mater and bony defect reconstruction were performed. (3) Results: The histological examination revealed meningothelial meningioma (WHO G1). Decreased CDVA and VF defects completely recovered, and the color vision score and PVEP improved following the surgery, but RNFL and GCC remained impaired. No tumor recurrence was observed at a follow-up of 78 months. (4) Conclusions: Optic nerve dysfunction has the capacity to improve once the compression has been relieved despite the presence of the structural features of optic nerve atrophy.
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Ohta, Nobuo, Yusuke Suzuki, Azusa Hasegawa, Masaru Aoyagi, and Seiji Kakehata. "Carbon Ion Beam Radiotherapy for Sinonasal Malignant Tumors Invading Skull Base." Case Reports in Otolaryngology 2014 (2014): 1–4. http://dx.doi.org/10.1155/2014/241856.
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Objective. To evaluate the treatment outcome and prognostic factors in patients with sinonasal malignant tumors invading skull base.Study Design and Setting. A retrospective clinical study at the Yamagata University School of Medicine.Subjects and Methods. Three patients with sinonasal malignant tumors invading skull base were presented in present study. All patients were treated with carbon ion beam radiotherapy. The prescribed dose to the center of the clinical target volume was 64.0 GyE/16 fractions over 4 weeks at 4.0 GyE/fraction per day.Results. All patients completed carbon ion beam radiotherapy without an interval. The mean observation period was 39.6 months (range: 11–54 months). There were no local or regional recurrences in all cases; however, one patient had a metastasis in distant organs. Regarding the complications, visual loss was observed in one eye of one patient whose optic nerve was entirely involved by the tumor and field of carbon ion beam radiotherapy. Radiation induced brain injury was observed in two patients; however, these patients do not complain about neurological abnormality and had no treatment for radiation induced brain necrosis.Conclusions. Carbon ion beam radiotherapy for sinonasal malignant tumors invading the skull base showed therapeutic effectiveness.
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Mello, Paulo Andrade de, Luciana Ansaneli Naves, Aldo Pereira Neto, Eduardo Henrique Oliveira, Ivan Coelho Ferreira, Antônio Santos de Araújo Júnior, Franz Jooji Onishi, and Luiz Augusto Casulari. "Clinical and laboratorial characterization and post-surgical follow-up of 87 patients with non-functioning pituitary macroadenomas." Arquivos de Neuro-Psiquiatria 71, no. 5 (May 2013): 307–12. http://dx.doi.org/10.1590/0004-282x20130026.
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Objective:It was to assess the main characteristics of patients undergoing pituitary tumor surgery.Method:Eighty-seven patients (44 men; 44.8±13 years old) were included.Results:The main symptoms were visual alterations (87.3%), headache (70.1%), diminished libido (34.4%), galactorrhea (22.9%) and hair loss (19.5%). The axes affected were gonadotropic (72.6%), thyrotropic (48.4%) and corticotropic (38.7%), without significant changes after surgery. The average largest tumor diameter was 3.1 cm before surgery and 1.56 cm after surgery. The most frequent postoperative complications were hydro-electrolyte and acid-base disorders (12%), diabetes insipidus (9%), visual field alterations (9%), liquoric fistula (8%) and nasal obstruction (7%). The patients were affected by more than one complication.Conclusion:Although a decrease in tumor volume was achieved through surgery, hormonal deficiencies persisted in most of the patients and new surgical approaches were necessary for dealing with tumor recurrence or persistence.
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Ghoshal, Rituparna, Sharanjeet Sharanjeet-Kaur, Norliza Mohamad Fadzil, Somnath Ghosh, Nor Fariza Ngah, and Roslin Azni Binti Abd Aziz. "Visual Parameters and Retinal Morphology for Polypoidal Choroidal Vasculopathy Pre- and Post-Intravitreal Ranibizumab with or without Photodynamic Therapy: A Short-Term Prospective Study." International Journal of Environmental Research and Public Health 18, no. 5 (March 4, 2021): 2581. http://dx.doi.org/10.3390/ijerph18052581.
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The objective of this study was to compare visual parameters and retinal layers’ morphology pre-treatment (baseline) and 6 months post-treatment in polypoidal choroidal vasculopathy (PCV) eyes. A single centre, longitudinal, prospective study was conducted at a public tertiary hospital of Malaysia. Visual parameters including distance and near visual acuity (DVA and NVA), contrast sensitivity (CS), reading speed (RS), and different qualitative and quantitative optical coherence tomography (OCT) parameters were evaluated pre- and 6 months post-treatment. Thirty-three naïve PCV eyes of 32 patients (mean age of 67.62 years) were evaluated pre- and post-treatment of intravitreal ranibizumab with and without photodynamic therapy. After treatment, sub retinal fluid decreased from 27 eyes (84.35%) at baseline to 7 eyes (21.88%) at 6 months while pigment epithelium detachment decreased from 32 eyes (100%) at base line to 15 eyes (46.87%) at 6 months. Mean pre-treatment quantitative morphological OCT retinal parameters including thickness and volume of central sub field, center thickness, center minimum, and maximum thickness reduced significantly. Similarly, all visual parameters including DVA, NVA, CS, and RS showed statistically significant improvement. While 89% of the eyes showed improvement in CS, 78%, 71%, and 65% of the eyes showed improvement in NVA, RS, and DVA, respectively. Thus, CS was the most treatment responsive visual parameter.
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Pavlova, Olena. "Visual Anthropology: Formation Stages and Basic Elements of Analysis." NaUKMA Research Papers. History and Theory of Culture 5 (September 6, 2022): 47–53. http://dx.doi.org/10.18523/2617-8907.2022.5.47-53.
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The article contributes to the history systematization of the visual anthropology area. The author considers and conceptualizes the stages of this discipline formation not only in accordance with the logic of self-understanding of its representatives, but also taking into account the genesis of optical media. The parameters of video production prove not only the instrumental role of visual anthropology in relation to the field of cultural anthropology, but also allow the latter to be a science in the strict sense of the term; that is, to have not only theoretical generalizations but also a rich empirical base. The inability of textual forms of recording anthropological material to adequately capture the cultural practices of traditional communities has also revealed the preserving and even salvage potential of the video production. However, the dominant of writing as a basic practice of science and its definition as a transparent carrier of scientific discourse did not allow to understand, at the initial stages. the innovative potential of visual anthropology, the specifics of its optics and methodology. The article pays attention both to the specifics of the practice of fixing video products (painting, photography, cinema, and the Internet) and to the forms of the representatives reflection of anthropological thought about their influence on the anthropology subject field. In this article, particular attention is paid to the degree of differentiation of cultural anthropology subject fields and visual anthropology against the background of basic transformations of cultural research. The influence of basic theoretical guidelines, in particular the principle of historical rationalism, participation in the formation of visual anthropology area itself, is also defined. In addition to theoretical principles and procedures of description, as well as comprehension of visual products and guidelines of research communities, the methodological significance of other parameters, formed as basic units of visual anthropology, are analyzed: technical parameters of optical media, the order of signifiers of visual representations, communication between video production and the audience. The author presents the disciplinary and historical context of the genesis of visual anthropology, as well as analyzes the conceptual logic of collective work edited by Paul Hockings “Principles of Visual Anthropology,” which is considered a fundamental work for self-awareness of this research area.
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Sukina, Ludmila. "Visual Sources of Old Russia in Historical Research: Some Methodological Observations." Philosophy. Journal of the Higher School of Economics IV, no. 4 (December 30, 2020): 113–32. http://dx.doi.org/10.17323/2587-8719-2020-4-113-132.
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The article considers the problem of the methodological difficulties of the work of historians with visual sources of Old Russia. Its relevance is determined by the paradoxical epistemological situation that has developed in historical science as a result of a visual turn. Historians who are researching Old Russia and constantly experiencing a shortage of sources could significantly expand the source base at their disposal, but they traditionally do not appreciate the information potential of ancient Russian art. The article analyzes methodological ideas related to the problems of “decryption” and interpretation of information from Russian and European medieval visual sources contained in the works of structuralism (Lotman, Uspensky), specialists in the field of iconography and iconology (Panofsky, Gombrich), symbolic history (M. Pasturo), soutce study methodologist Lappo-Danilevsky. The species and historical features of this type of sources create serious difficulties for historians, require the development of a methodology for working with “unrealistic” images, but also open up prospects for a meaningful enrichment of research. Russian and foreign science has accumulated sufficient theoretical and practical experience in this area. Therefore it is hoped that research on the visual sources of Old Russia will expand and take its rightful place in the corpus of historical knowledge.
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Lozitska, N. "Sunspot magnetic fields in 24 cycle of solar activity." Bulletin of Taras Shevchenko National University of Kyiv. Astronomy, no. 58 (2018): 11–17. http://dx.doi.org/10.17721/btsnua.2018.58.11-17.
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The data of visual measurements of the magnetic field in sunspots umbra, obtained in four observatories during 24 cycles of solar activity, are compared. Magnetic field strength modules with averaging over each observatory are analyzed. The measurements taken in the Astronomical Observatory of the University of Kyiv (KAO) were used as base, where 170 spots were measured on average 4 times each at intervals of one to two daysduring the group passing through the solar disk. Measurements of the Ural, Crimean and Mount Wilson Observatory, performed within 24 hours of observation in the KAO, are used in the study. It was found that the average value of the magnetic field per cycle, obtained from the data of three observatories UrAO, CrAO and KAO, was 26.0 ± 0.3, 25.0 ± 0.2 and 25.2 ± 0.2 cT, respectively. They differ by no more than 3 standard errors, while the Mount Wilson Observatory gives a significantly lower magnetic field – 23.8 ± 0.1 cT. This result is confirmed by the work of R. Rezaei et al., 2015, which compares the visual measurements in Mount Wilson with Tenerife Infrared Polarimeter (TIP) and Facility InfRared Spectropolarimeter (FIRS) for the 23rd and 24th cycle of solar activity. The average magnetic field value for observations of TIP and FIRS in 24 cycles is 26.0 cT, which is slightly higher than we obtained from the visual observations of three observatories, while MtW shows a few centitesla less. The mean square error of the average per cycle of the magnetic field, based on the data of TIP and FIRS is 0.2 cT, so the difference with the MtW is reliable. An understatement of the measured intensity of the magnetic field of the spots requires a revision of the measurement calibration in Mount Wilson. The data of the Crimean Astrophysical Observatory can be considered reference for subsequent comparisons with the results of observations of other observatories. For the calculation of the annual index Bsp of magnetic fields of sunspot size 22-44 Mm, the data of visual measurements of all 4 observatories are traditionally used. We have found that variations in the magnetic field of sunspots are the same as in previous cycles: the peak occurs in the second-third years after the maximum number of spots. The average for the 24 cycle Bsp index is 24.9 ± 0.3 сT, which allows us to consider this magnetic cycle as moderately strong. Reduction of the sunspots magnetic field in 2018 to 23 cT allows it to expect in 2019 the highest near-ground level of galactic cosmic rays in the last half century.
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Lee, B., S. W. Kang, J. Y. Kim, J. Lee, H. J. Kim, W. C. Kim, C. Song, et al. "Development of optical sensor system and hardware base frame for checking the light and radiation fields of a linear accelerator." Journal of Instrumentation 17, no. 11 (November 1, 2022): P11038. http://dx.doi.org/10.1088/1748-0221/17/11/p11038.
Full textAbstract:
Abstract This study aims to quantitatively evaluate the light and radiation fields of a linear accelerator by developing an optical sensor quality assurance (QA) system using a cadmium sulfide (CdS) photodetector cell and a hardware base frame manufactured in-house. The CdS photodetector cell used as the optical sensor has a size of 3.4 × 4.1 mm2, can measure up to 100 lux of light, and has a response time of approximately 20 to 30 ms. To check the alignment of the light field, it was manufactured with a CdS cell optical fiber holder, and the microcontroller board and control module were configured to scan the light field profile. Additionally, for accurate operation of the sensor, it was programmed using the integrated development environment (IDE) sketch. The alignment check of the radiation field was analyzed using the image data measured with electronic portal imaging device (EPID) using the manufactured hardware base frame. An analysis program written in MATLAB was used to evaluate the alignment of the radiation field. For symmetric fields measured using the optical sensor QA system, the full width at half maximum (FWHM) values of crossline (X) and inline (Y) profiles were 100.391 mm and 98.725 mm, respectively, for a field size of 100 × 100 mm2, and 199.093 mm and 198.886 mm, respectively, for a field size of 200 × 200 mm2. The X and Y FWHM values measured by the sensor system for the light fields were within 1 mm of the field size of the visual inspection. In addition, the FWHM value of the asymmetric radiation field measured using the fabricated frame and EPID was measured from the center bearing ball of the field to the bearing ball in each field of the four directions in the EPID image, and when the X1, X2, Y1, and Y2 jaws were opened by 50 mm, FWHM values were 50.120 mm, 50.240 mm, 48.860 mm, and 49.870 mm, respectively. The corresponding values were 99.520 mm, 99.570 mm, 99.010 mm, and 99.880 mm when the jaw fields were opened by 100 mm. The optical sensor system and hardware base frame developed in this study demonstrated the ability to evaluate both light and radiation fields more simply and quantitatively when compared to the conventional QA process. This QA system will provide medical physicists with more reliable QA results than the conventional QA method that uses graph paper and film.
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Desai, Chitra. "Image Classification Using Transfer Learning and Deep Learning." International Journal of Engineering and Computer Science 10, no. 9 (September 23, 2021): 25394–98. http://dx.doi.org/10.18535/ijecs/v10i9.4622.
Full textAbstract:
Deep learning models have demonstrated improved efficacy in image classification since the ImageNet Large Scale Visual Recognition Challenge started since 2010. Classification of images has further augmented in the field of computer vision with the dawn of transfer learning. To train a model on huge dataset demands huge computational resources and add a lot of cost to learning. Transfer learning allows to reduce on cost of learning and also help avoid reinventing the wheel. There are several pretrained models like VGG16, VGG19, ResNet50, Inceptionv3, EfficientNet etc which are widely used. This paper demonstrates image classification using pretrained deep neural network model VGG16 which is trained on images from ImageNet dataset. After obtaining the convolutional base model, a new deep neural network model is built on top of it for image classification based on fully connected network. This classifier will use features extracted from the convolutional base model.