301 research outputs found
Development of composite calibration standard for quantitative NDE by ultrasound and thermography
No full textInspection of aircraft components for damage utilizing ultrasonic Non-Destructive Evaluation (NDE) is a time intensive endeavor. Additional time spent during aircraft inspections translates to added cost to the company performing them, and as such, reducing this expenditure is of great importance. There is also great variance in the calibration samples from one entity to another due to a lack of a common calibration set. By characterizing damage types, we can condense the required calibration sets and reduce the time required to perform calibration while also providing procedures for the fabrication of these standard sets. We present here our effort to fabricate composite samples with known defects and quantify the size and location of defects, such as delaminations, and impact damage. Ultrasonic and Thermographic images are digitally enhanced to accurately measure the damage size. Ultrasonic NDE is compared with thermography.This proceeding may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing.
This proceeding appeared in Dayal, Vinay, Zach G. Benedict, Nishtha Bhatnagar, and Adam G. Harper. "Development of composite calibration standard for quantitative NDE by ultrasound and thermography." In AIP Conference Proceedings, vol. 1949, no. 1, p. 060006. AIP Publishing LLC, 2018, and may be found at
DOI: 10.1063/1.5031552.
Copyright 2018 The Author(s).
Posted with permission
Kearns-Sayre syndrome
No full textKearns-Sayre syndrome (KSS) is a rare neuromuscular disorder. We report a case of a 14-year-old boy diagnosed and treated as myasthenia gravis for (4) years who was eventually diagnosed with KSS. He reported to us 3 years after initial presentation of mild drooping of eyelids with increased severity of ptosis, bilateral external ophthalmoplegia, and atypical retinitis pigmentosa. On multispecialty consultation, he was found to have right bundle branch block, wasting and weakness of limb muscles, and hearing loss. Sartorius muscle biopsy revealed ragged red fibres on trichrome stain. All these findings confirmed the diagnosis of Kearns-Sayre Syndrome (KSS). The take home message is to have a high index of suspicion for KSS when encountering cases of musculoskeletal disorders in subjects below 20 years of age in view of high morbidity and mortality associated with this syndrome
Ophthalmologists saving life of a young patient presenting with sudden simultaneous bilateral retinal artery occlusions secondary to calcific emboli of cardiac origin
No full textWe present a case report of a young 35-year-old previously healthy male with simultaneous central retinal artery occlusion in the right eye and branch retinal artery occlusion in the left eye with visible calcific emboli in both eyes from calcified mitral valve diagnosed on trans-esophageal echocardiography. Patient underwent an urgent life-saving mitral valve replacement surgery within 2 days as Ophthalmologists immediately referred him to Cardiologist moment they visualized calcific emboli in both eyes with bilateral retinal artery occlusions on fundoscopy. Bilateral retinal artery occlusions suggest a source of emboli at the level of the heart or aortic arch. All patients with retinal ischemia should have a complete cardiovascular evaluation supplemented by Transesophageal echocardiography. Many times an Ophthalmologist might be the physician of first contact for patients with cardiac diseases and awareness of the disease is therefore important for all Ophthalmologists. Timely referral and management by Cardiologist/cardiac surgeon may protect patient against serious life-threatening complications
Spiritual leadership for sustainable development policy
No full textSpirituality and leadership, both have an intrinsic goal where they incorporate clarity of understanding, vision and collective action and both have the potential to empower an individual or a team, with commitment and productivity. It is one of the rapidly growing areas of leadership. It takes responsible policymakers and leaders to build a nation that benefits multiple stakeholders and all citizens. The aim of the chapter is to explore the concept of spirituality and show how applied spirituality can provide moral and practical guidance for leaders of public policy to take bold and enlightened steps towards achieving sustainable development (SD) goals. We define spirituality as a way of understanding, inner awareness, personal integration, and a source of values that give ultimate meaning or purpose beyond the egoic self. As such the chapter will go beyond existing discussions of ethical, moral, or values-based leadership and raise issues of how a deeper spiritual understanding of human nature can guide leaders. Some helpful practices like mindfulness are also covered in this chapter. There are various relevant leadership styles including transformational leadership, servant leadership, moral leadership and participatory leadership. Although each of these has some positive characteristics, this chapter with the help of those characteristics would try to get a deeper insight and understanding of how spirituality can stimulate and add more value, and bring integrity, motivation and strong leadership qualities. This chapter covers the existing gap in the literature on applied spirituality and leadership and concludes that leadership when incorporated with spirituality plays a vital role in honing the skills of the leaders and changing their perspective towards the team. The chapter will conclude with ideas for discussion among faculty and students and suggestions for further research into the use of applied spirituality for leadership in sustainable development polic
Universal Statistical Properties of Inertial-particle Trajectories in Three-dimensional, Homogeneous, Isotropic, Fluid Turbulence
No full textWe obtain new universal statistical properties of heavy-particle trajectories in three-dimensional, statistically steady, homogeneous, and isotropic turbulent flows by direct numerical simulations. We show that the probability distribution functions (PDFs) P(Φ), of the angle Φ between the Eulerian velocity u and the particle velocity v, at a point and time, scales as P(Φ) ∼Φ−, with a new universal exponent ≃ 4
Performance and hardware complexity analysis of programmable radio platform for MIMO OFDM based WLAN systems
No full textEmerging wireless technologies and standards present a design space with multiple dimensions in terms of time, physical hardware space, and technology trends. Efficient evaluation of a desired combination of these dimensions to support multiple technologies and standards presents a significant challenge. We study the feasibility of a multiprotocol architecture without sacrificing the Quality of Service. An architecture facilitating such a mechanism can be implemented at different layers in the network stack with each layer offering a tradeoff between complexity and latency. Careful analysis of the physical layer reveals that most blocks of the transceiver can be reused for different protocols without significant architectural change. In addition to the feasibility analysis, we also identify common blocks in the network stack that could be possibly reused buying us significant hardware gains without sacrificing the aggregate system throughput. Our study presents the gate count complexity and the performance analysis of programmable radio architecture with the 802.11n (Draft 3.0) MIMO-OFDM based protocol stream and 802.11a OFDM based WLAN protocol stream. In this thesis, we demonstrate that multiple protocols can be supported using the same hardware under acceptable latency requirements. Complexity of the system in terms of gate count has been determined. It has been found that for shorter frame sizes, it is better to process less number of OFDM symbols at a time. However, for larger frame sizes, it is beneficial to process large number (four to eight) of OFDM symbols at a time. Also, the minimum clock rate required to run the hardware, would vary depending upon the number of OFDM Symbols processed. The switching and multiplexing overhead of the programmable radio platform has also been investigated. Finally, our simulator is capable of evaluating bottlenecks, if any.M.S.Includes bibliographical references (p. 75-76)
Influence of deformable substrates on macroscopic and microscopic phenomenon of tissue
No full textOne of the most important aspects by which cells adapt to their environment is their interaction with their extracellular matrix. The goal of this thesis is to design deformable substrates with controllable mechanical and biochemical properties and to understand cell-substrate interaction at both microscopic and macroscopic scales. First part of the thesis aims to develop biodegradable hydrogels as delivery vehicles for cellular and small molecular therapeutics and also for potential tissue engineering constructs. The second part deals with development of an assessment tool for analyzing changes in tissue mechanics. In the first part of this thesis, we studied the interaction of the dental pulp stem cells with enzymatically crosslinked gelatin hydrogels of tunable stiffness (8KPa-0.1KPa). Dental pulp stem cells (DPSCs) are known to undergo odontogenesis when grown with Dexamethasone (Dex). The purpose of this study was to investigate the odontogenic impact of substrates on DPSCs in the absence of Dex. Through our experiments we identified hydrogels that support DPSC biomineralization and odontogenesis. These scaffolds were self-mineralizing and may prove useful as a biodegradable scaffold for dentin regeneration. In the second part, we prepared physically crosslinked polymer composite hydrogels of variable stiffness. We studied the rheological properties of these hydrogel scaffolds and related it to the type of bonding, degree of crosslinking and mechanical structure of the hydrogels. We showed the successful application of these hydrogels as potential drug delivery vehicles by studying the controlled release of Salicylic Acid. Their potential use as tissue engineered constructs was also shown by dermal fibroblasts adhesion and proliferation. In the last part of this thesis, we successfully developed a non-invasive Digital Image Speckle Correlation (DISC) technique for the precise quantification of the magnitude and duration of facial muscle paralysis inflicted by the Botulinum toxin (BTX-A). We were able to precisely characterize the mechanics of skin abnormalities and macroscopic response of collective cellular motion. Due to the generality of this method we were able to extend the use of DISC for diagnosis and prognosis of patients with vestibular schwannomas. Our results are based on successful human clinical trials of vestibular schwannomas and facial paralysis patients,136 page
Influence of deformable substrates on macroscopic and microscopic phenomenon of tissue
No full text136 pg.One of the most important aspects by which cells adapt to their environment is their interaction with their extracellular matrix. The goal of this thesis is to design deformable substrates with controllable mechanical and biochemical properties and to understand cell-substrate interaction at both microscopic and macroscopic scales. First part of the thesis aims to develop biodegradable hydrogels as delivery vehicles for cellular and small molecular therapeutics and also for potential tissue engineering constructs. The second part deals with development of an assessment tool for analyzing changes in tissue mechanics. In the first part of this thesis, we studied the interaction of the dental pulp stem cells with enzymatically crosslinked gelatin hydrogels of tunable stiffness (8KPa-0.1KPa). Dental pulp stem cells (DPSCs) are known to undergo odontogenesis when grown with Dexamethasone (Dex). The purpose of this study was to investigate the odontogenic impact of substrates on DPSCs in the absence of Dex. Through our experiments we identified hydrogels that support DPSC biomineralization and odontogenesis. These scaffolds were self-mineralizing and may prove useful as a biodegradable scaffold for dentin regeneration. In the second part, we prepared physically crosslinked polymer composite hydrogels of variable stiffness. We studied the rheological properties of these hydrogel scaffolds and related it to the type of bonding, degree of crosslinking and mechanical structure of the hydrogels. We showed the successful application of these hydrogels as potential drug delivery vehicles by studying the controlled release of Salicylic Acid. Their potential use as tissue engineered constructs was also shown by dermal fibroblasts adhesion and proliferation. In the last part of this thesis, we successfully developed a non-invasive Digital Image Speckle Correlation (DISC) technique for the precise quantification of the magnitude and duration of facial muscle paralysis inflicted by the Botulinum toxin (BTX-A). We were able to precisely characterize the mechanics of skin abnormalities and macroscopic response of collective cellular motion. Due to the generality of this method we were able to extend the use of DISC for diagnosis and prognosis of patients with vestibular schwannomas. Our results are based on successful human clinical trials of vestibular schwannomas and facial paralysis patientsAdvisor(s): Rafailovich, Miriam H. Committee Member(s): Sokolov, Jonathan ; Jurukovski, Vladimir ; Simon, Marcia.Stony Brook University Libraries. SBU Graduate School in Department of Materials Science and Engineering. Charles Taber (Dean of Graduate School)
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