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https://www.readbyqxmd.com/read/28438004/autofocusing-airy-beams-generated-by-all-dielectric-metasurface-for-visible-light
#1
Qingbin Fan, Daopeng Wang, Pengcheng Huo, Zijie Zhang, Yuzhang Liang, Ting Xu
Conventional method to generate autofocusing Airy (AFA) beam involves the optical Fourier transform (FT) system, which has a fairly long working distance due to the focal length of FT lens, presence of spatial light modulator (SLM) and auxiliary total reflection mirrors. Here, we propose an extremely compact design to generate high-efficiency AFA beam at visible frequency by using metasurface which is composed of a single layer array of amorphous titanium dioxide (TiO<sub>2</sub>) elliptical nanofins sitting on the fused-silica substrate...
April 17, 2017: Optics Express
https://www.readbyqxmd.com/read/28437969/experimental-generation-of-complex-optical-fields-for-diffraction-limited-optical-focus-with-purely-transverse-spin-angular-momentum
#2
Jian Chen, Chenhao Wan, Lingjiang Kong, Qiwen Zhan
We demonstrate a method to generate complex optical fields at the pupil plane of a high numerical aperture (NA) objective lens for the creation of diffraction limited optical focus with purely transverse spin angular momentum. The complex optical fields are analytically deduced through reversing the radiated patterns from two electric dipoles, which are located at the focal point of the high NA lens and oscillate respectively in x- and z- directions with phase difference of π/2. The derived fields can be experimentally created with a vectorial optical field generator...
April 17, 2017: Optics Express
https://www.readbyqxmd.com/read/28437967/design-of-see-through-near-eye-display-for-presbyopia
#3
Yishi Wu, Chao Ping Chen, Lei Zhou, Yang Li, Bing Yu, Huayi Jin
We propose a compact design of see-through near-eye display that is dedicated to presbyopia. Our solution is characterized by a plano-convex waveguide, which is essentially an integration of a corrective lens and two volume holograms. Its design rules are set forth in detail, followed by the results and discussion regarding the diffraction efficiency, field of view, modulation transfer function, distortion, and simulated imaging.
April 17, 2017: Optics Express
https://www.readbyqxmd.com/read/28437964/passively-coupled-low-coherence-interferometric-duct-profiling-with-an-astigmatism-corrected-conical-mirror
#4
Helen D Ford, Ralph P Tatam
Duct-profiling in test samples up to 25 mm in diameter has been demonstrated using a passive, low-coherence probe head with a depth resolution of 7.8 μm, incorporating an optical-fibre-linked conical mirror addressed by a custom-built array of single-mode fibres. Zemax modelling, and experimental assessment of instrument performance, show that degradation of focus, resulting from astigmatism introduced by the conical mirror, is mitigated by the introduction of a novel lens element. This enables a good beam focus to be achieved at distances of tens of millimetres from the cone axis, not achievable when the cone is used alone...
April 17, 2017: Optics Express
https://www.readbyqxmd.com/read/28437961/novel-asymmetric-cryptosystem-based-on-distorted-wavefront-beam-illumination-and-double-random-phase-encoding
#5
Honghao Yu, Jun Chang, Xin Liu, Chuhan Wu, Yifan He, Yongjian Zhang
Herein, we propose a new security enhancing method that employs wavefront aberrations as optical keys to improve the resistance capabilities of conventional double-random phase encoding (DRPE) optical cryptosystems. This study has two main innovations. First, we exploit a special beam-expander afocal-reflecting to produce different types of aberrations, and the wavefront distortion can be altered by changing the shape of the afocal-reflecting system using a deformable mirror. Then, we reconstruct the wavefront aberrations via the surface fitting of Zernike polynomials and use the reconstructed aberrations as novel asymmetric vector keys...
April 17, 2017: Optics Express
https://www.readbyqxmd.com/read/28436843/fabrication-and-performance-of-a-miniaturized-and-integrated-endoscope-ultrasound-convex-array-for-digestive-tract-imaging
#6
Jue Peng, Xiaojian Peng, Hu Tang, Xiaozhen Li, Ruimin Chen, Yang Li, Tianfu Wang, Siping Chen, Koping Shung, Qifa Zhou
OBJECTIVE: This work presents the design, fabrication and testing of a miniaturized and integrated ultrasound endoscope for use as an in situ digestive diagnostic device to facilitate real-time ultrasound guidance of intervention treatments. METHODS: We designed an optimal structure to integrate an auto-focus 5-megapixel camera module with an 8-MHz, 64-element curvilinear ultrasonic array in one miniaturized package. A novel three-axis auto-focusing voice coil motor (VCM) was designed and manufactured for the camera module to move the lens position for auto-focusing and to adjust the lens tilt...
April 24, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28436783/recognizing-the-patient-s-criticism-of-the-analyst
#7
Joan Sacks Lentz
Difficulty hearing criticism of us by our patients continues to be widespread among clinicians and interferes with progress in treatment. Analysts may have trouble hearing criticism because it is well hidden in the patient's associations or because it is difficult for them to recognize their shortcomings. The author suggests that the analyst's failure to hear criticism prevents the patient from resolving what may be the final, unhealthy ties to past objects. With a lens deliberately trained on criticism in our patients' material, analysts may be surprised by the myriad forms of criticism that are present and by the importance of receptive listening...
April 2017: Psychoanalytic Review
https://www.readbyqxmd.com/read/28436640/intravitreal-aflibercept-for-patients-with-diabetic-macular-edema-refractory-to-bevacizumab-or-ranibizumab-analysis-of-response-to-aflibercept
#8
Yen-Yi Chen, Pei-Yao Chang, Jia-Kang Wang
PURPOSE: To investigate the short-term efficacy and safety of intravitreal aflibercept in a case series of patients with diabetic macular edema (DME) refractory to ranibizumab or bevacizumab. DESIGN: A retrospective chart review. METHODS: From September 2013 to March 2016, we identified patients with DME who developed resistance to bevacizumab or ranibizumab. Three monthly intravitreal aflibercept injections were administered in refractory cases...
April 10, 2017: Asia-Pacific Journal of Ophthalmology
https://www.readbyqxmd.com/read/28435617/analysis-of-the-width-ratio-and-wear-rate-of-maxillary-anterior-teeth-in-the-korean-population
#9
Yeon-Ah Oh, Hong-So Yang, Sang-Won Park, Hyun-Pil Lim, Kwi-Dug Yun, Chan Park
PURPOSE: The purpose of this study was to compare the width ratio of maxillary anterior teeth according to age in the Korean population and to evaluate the maxillary central incisor width-to-length (W/L) ratio, given differences in age and gender. MATERIALS AND METHODS: Ninety-three Korean adults were divided into 3 groups (n = 31) by age. Group I was 20 - 39 years old, Group II was 40 - 59 years old, and Group III was over 60 years of age. After taking an impression and a cast model of the maxillary arch, the anterior teeth width ratio and central incisor W/L ratio were calculated from standard digital images of the cast models using a graph paper with a digital single lens reflex (DSLR) camera...
April 2017: Journal of Advanced Prosthodontics
https://www.readbyqxmd.com/read/28435215/a-comparison-of-mesopic-visual-acuity-and-objective-visual-quality-following-cataract-surgery-with-hydrophobic-acrylic-intraocular-lenses
#10
George Hh Beiko, Miso Gostimir, Lila Haj-Ahmad
PURPOSE: To evaluate mesopic visual acuity and visual quality as measured by objective scatter index (OSI) in pseudophakic eyes with long-term follow-up after implantation of hydrophobic acrylic lenses made from two different lens materials. SETTING: This study was carried out in a private clinic. DESIGN: This study was an observational cohort study. METHODS: This pilot study included 181 eyes of 136 patients who had undergone cataract surgery with implantation of monofocal hydrophobic acrylic intraocular lenses (IOLs), either Alcon AcrySof (82 eyes) or Abbott Medical Optics' Tecnis (99 eyes)...
2017: Clinical Ophthalmology
https://www.readbyqxmd.com/read/28434953/the-multi-scope-technique-for-microvascular-decompression
#11
Yuichi Nagata, Tadashi Watanabe, Tetsuya Nagatani, Kazuhito Takeuchi, Jonsu Chu, Toshihiko Wakabayashi
BACKGROUND: The performance of endoscopic surgery has rapidly become widespread in neurosurgery in recent years. Endoscopy can offer close and panoramic surgical views with fine illumination, even in the deep intracranial area. However, it also has the following serious drawback: an intracranial blind area between the field lens of the endoscope and the site of the dural opening. This blind area cannot be viewed on the endoscopic monitor, and several surgical complications, including accidental intracranial neurovascular structural injury, can occur in this area...
April 18, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28434250/rolling-tobacco-in-banana-leaves-newspaper-or-copybook-paper-associated-with-significant-reduction-in-lung-function-in-vanuatu
#12
Charles A Weitz, Kathryn M Olszowy, Kelsey N Dancause, Cheng Sun, Alysa Pomer, Howard Silverman, G Lee, Len Tarivonda, Chim W Chan, Akira Kaneko, J K Lum, Ralph M Garruto
In addition to the widespread availability of packaged cigarettes, the inhabitants of island nations of the Southwest Pacific frequently smoke commercially available loose tobacco using manufactured rolling papers, as well as locally grown tobacco rolled in manufactured rolling paper or wrapped in leaves, copybook paper, and newspaper. In this study, Vanuatu men who smoked local tobacco rolled in leaves, copybook paper, or newspaper showed significantly lower forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and FEV1/FVC ratios than men who smoked packaged cigarettes, store-bought tobacco rolled in manufactured rolling paper, or who smoked locally grown tobacco rolled in manufactured rolling papers...
April 2017: Asia-Pacific Journal of Public Health
https://www.readbyqxmd.com/read/28433446/functional-magnetic-resonance-imaging-to-assess-the-neurobehavioral-impact-of-dysphotopsia-with-multifocal-intraocular-lenses
#13
Andreia M Rosa, Ângela C Miranda, Miguel Patrício, Colm McAlinden, Fátima L Silva, Joaquim N Murta, Miguel Castelo-Branco
PURPOSE: To investigate the association between dysphotopsia and neural responses in visual and higher-level cortical regions in patients who recently received multifocal intraocular lens (IOL) implants. DESIGN: Cross-sectional study. PARTICIPANTS: Thirty patients 3 to 4 weeks after bilateral cataract surgery with diffractive IOL implantation and 15 age- and gender-matched control subjects. METHODS: Functional magnetic resonance imaging (fMRI) was performed when participants viewed low-contrast grating stimuli...
April 19, 2017: Ophthalmology
https://www.readbyqxmd.com/read/28432482/the-sensible-health-care-professional-a-care-ethical-perspective-on-the-role-of-caregivers-in-emotionally-turbulent-practices
#14
Vivianne Baur, Inge van Nistelrooij, Linus Vanlaere
This article discusses the challenging context that health care professionals are confronted with, and the impact of this context on their emotional experiences. Care ethics considers emotions as a valuable source of knowledge for good care. Thinking with care ethical theory and looking through a care ethical lens at a practical case example, the authors discern reflective questions that (1) shed light on a care ethical approach toward the role of emotions in care practices, and (2) may be used by practitioners and facilitators for care ethical reflection on similar cases, in the particular and concrete context where issues around emotional experiences arise...
April 21, 2017: Medicine, Health Care, and Philosophy
https://www.readbyqxmd.com/read/28432184/management-of-a-case-of-myopic-foveoschisis-with-phakic-intraocular-lens-piol-in-situ-intraoperative-challenges
#15
Atul Kumar, Aditi Mehta, Raghav Dinesh Ravani, Prateek Kakkar
We describe the case of a 30-year-old man with pathological myopia with a phakic intraocular lens (IOL) (Visian ICL V4c model; STAAR, Monrovia, California, USA) in situ having complaints of metamorphopsia in the left eye with documented myopic foveoschisis on swept-source optical coherence tomography (DRI OCT Triton; Topcon, Tokyo, Japan). The patient underwent pars plana vitrectomy with internal limiting membrane peeling. This report discusses the intraoperative challenges occurring as a result of increased optical aberrations in the presence of a phakic IOL...
April 20, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28431469/enhanced-response-time-of-electrowetting-lenses-with-shaped-input-voltage-functions
#16
Omkar D Supekar, Mo Zohrabi, Juliet T Gopinath, Victor M Bright
Adaptive optical lenses, based on the electrowetting principle, are being rapidly implemented in many applications such as microscopy, remote sensing, displays, and optical communication. To characterize the response of these electrowetting lenses, the dependence on DC driving voltage functions was investigated in a low viscosity liquid system. Cylindrical lenses with inner diameter 2.45 and 3.95-mm were used to characterize the dynamic behavior of the liquids under DC voltage electrowetting actuation. By increasing the rise time of the input exponential driving voltage, the originally underdamped system response can be damped, enabling a smooth response from the lens...
April 21, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28431458/reclaiming-our-spirits-development-and-pilot-testing-of-a-health-promotion-intervention-for-indigenous-women-who-have-experienced-intimate-partner-violence
#17
Colleen Varcoe, Annette J Browne, Marilyn Ford-Gilboe, Madeleine Dion Stout, Holly McKenzie, Roberta Price, Victoria Bungay, Victoria Smye, Jane Inyallie, Linda Day, Koushambhi Khan, Angela Heino, Marilyn Merritt-Gray
Indigenous women are subjected to high rates of multiple forms of violence, including intimate partner violence (IPV), in the context of ongoing colonization and neo-colonization. Health promotion interventions for women who experience violence have not been tailored specifically for Indigenous women. Reclaiming Our Spirits (ROS) is a health promotion intervention designed for Indigenous women living in an urban context in Canada. In this paper, we describe the development of the intervention, results of a pilot study, and the revised subsequent intervention...
April 21, 2017: Research in Nursing & Health
https://www.readbyqxmd.com/read/28430806/incidence-and-risk-factors-for-post-penetrating-keratoplasty-glaucoma-a-systematic-review-and-meta-analysis
#18
Suqian Wu, Jianjiang Xu
OBJECTIVES: To establish the incidence and risk factors for post penetrating keratoplasty glaucoma (PKKG). METHODS: Studies published between 1947 and 2016 regarding penetrating keratoplasty (PK) were identified using an electronic search and reviewed. For search purpose, PKKG was defined as ocular hypertension (> 21mmHg) after PK. The incidence and risk factors of PKKG were extracted for all studies. Pooled incidence, odd ratios (ORs) and 95% confidence intervals (CIs) were calculated...
2017: PloS One
https://www.readbyqxmd.com/read/28430336/an-italian-translation-and-validation-of-the-near-activity-visual-questionnaire-navq
#19
Fabrizio Zeri, Isabella Beltramo, Laura Boccardo, Paolo Palumbo, Vincenzo Petitti, James S Wolffsohn, Shehzad A Naroo
PURPOSE: To validate the Near Activity Vision Questionnaire (NAVQ) in Italian to allow the assessment of presbyopia corrections in Italian-speaking patients. METHODS: An Italian version of the NAVQ was arranged through several steps: an initial forward translation (from English to Italian), a backward translation (from Italian to English), and finally a consensual version to check against the original NAVQ. This prospective study enrolled native Italian-speaking presbyopic patients with corrected distance visual acuity of 0...
April 11, 2017: European Journal of Ophthalmology
https://www.readbyqxmd.com/read/28430334/chondro-keratoprosthesis-an-alternative-to-ookp
#20
Louis Hoffart, Laurent Guyot
PURPOSE: To evaluate the use of cartilage as a potential graft material toward osteo-odontal tissue replacement in keratoprosthesis surgery. METHODS: We describe a modification of the osteo-odonto-keratoprosthesis surgery that involves the use of autologous auricular conchal cartilage graft (ACCG). In stage 1a, a full-thickness cheek mucosa graft was performed over the ocular surface. In stage 1b, ACCG was harvested via a retroauricular approach. An optical polymethyl-methacrylate cylinder was embedded into a double-layered fragment of cartilage and secured by cyanoacrylate glue...
April 4, 2017: European Journal of Ophthalmology
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