Cone beam computed tomography evaluation of variations in the sella turcica in a Turkish population

Background: The aim of the study was to analyse the variations of the sella turcica and their relationship to age and gender. Materials and methods: The cone beam computed tomography (CBCT) images of the patients who referred to Gaziantep University, Faculty of Dentistry, Department of Dentomaxillofacial Radiology were analysed by two examiners and 200 CBCT images were evaluated retrospectively. Sella turcica shapes of individuals were described according to Axelsson’s classification as either normal or with aberrations including: oblique anterior wall, double contour of the floor, sella turcica bridging, irregularity in the posterior part of the dorsum sella, and pyramidal shape of the dorsum sella. Results: Normal sella turcica was the most common type seen in 100 (49.8%) individuals. The secondary common type was double contour of the floor of sella turcica seen in 46 (22.9%) patients. Thirty-two (15.9%) patients had oblique anterior wall. Seventeen (8.5%) individuals had pyramidal shape of the dorsum sella, 3% irregularity in the posterior part of the sella turcica. None of the patients had sella turcica bridging. Irregularity in the posterior part of the sella turcica and pyramidal shape of the dorsum sella were reported significantly more frequent in female than male. Conclusions: Sella turcica varies in shape and morphology regardless of age. Normal sella turcica was the most frequent type in the study group. Irregularity in the posterior part of the sella turcica and pyramidal shape of the dorsum sella were reported more frequent in female than male

Vibration-based monitoring of civil infrastructure: challenges and successes

Author's manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s13349-011-0009-5© Springer-Verlag 2011Co -published with International Society for Structural Health Monitoring of Intelligent InfrastructureStructural health monitoring (SHM) is a relatively new paradigm for civil infrastructure stakeholders including operators, consultants and contractors which has in the last two decades witnessed an acceleration of academic and applied research in related areas such as sensing technology, system identification, data mining and condition assessment. SHM has a wide range of applications including, but not limited to, diagnostic and prognostic capabilities. However, when it comes to practical applications, stakeholders usually need answers to basic and pragmatic questions about in-service performance, maintenance and management of a structure which the technological advances are slow to address. Typical among the mismatch of expectation and capability is the topic of vibration-based monitoring (VBM), which is a subset of SHM. On the one hand there is abundant reporting of exercises using vibration data to locate damage in highly controlled laboratory conditions or in numerical simulations, while the real test of a reliable and cost effective technology is operation on a commercial basis. Such commercial applications are hard to identify, with the vast majority of implementations dealing with data collection and checking against parameter limits. In addition there persists an unhelpful association between VBM and 'damage detection' among some civil infrastructure stakeholders in UK and North America, due to unsuccessful transfer of technology from the laboratory to the field, and this has resulted in unhealthy industry scepticism which hinders acceptance of successful technologies. Hence the purpose of this paper is showcase successful VBM applications and to make the case that VBM does provide valuable information in real world applications when used appropriately and without unrealistic expectations. © 2011 Springer-Verlag

Anatomical evaluation of nasopalatine canal on cone beam computed tomography images

Background: Nasopalatine canal (NPC) (incisive canal) morphology is important for oral surgery techniques carried out on the maxilla, in the treatment of naso- palatine cyst, palatal pathologies that require a surgical intervention. Materials and methods: The morphology of NPC was classified in sagittal, coronal and axial planes on the cone beam computed tomography (CBCT). The length of NPC was found by measuring the distance between the mid-points of nasopalatine foramen and incisive foramen. The numbers, shapes and diameters of incisive and nasopalatine foramina were examined. Nasopalatine angle present between the NPC and the palate and anterior to the NPC was measured.  Results: In the sagittal plane, the shape of NPC was classified in six groups: 26.7% hourglass, 14.7% cone, 13.3% funnel, 16.0% banana, 28.7% cylindrical and 0.7% reverse-cone-shaped. In the coronal plane, shape of NPC was classified in three groups: 63.3% Y-shaped, 36.0% single canal, 0.7% double canal and external border of NPC was classified in four groups: 26.7% U, 28.7% Y, 44.0% V and 0.7% reverse-V-shaped. In the axial plane, the shape of nasopalatine foramen, incisive foramen and NPC at the mid-level was evaluated. The shape of the canal was detected as four types at three evaluated levels: round, oval, heart- and triangle-shaped. It was seen in every three axial planes that the round group is more than the others.  Conclusions: The morphological properties and variations of NPC should be con- sidered with a correct radiological evaluation so as to prevent the complications and improper practices in local anaesthesia, maxillary surgery and implant surgery practices. Especially dentists, otolaryngologist and plastic surgeons need to know the anatomy and variations of NPC.

Technology Leveraging for Infrastructure Asset Management: Challenges and Opportunities

Transportation and other infrastructure systems, particularly in dense urban regions, are intertwined, interdependent, multi-scale, multi-domain and complex, and their behavior cannot be predicted even when element behaviors are known. Such systems should be managed just like financial assets, leveraging measurement-based, objective and reliable metrics for documenting their value, performance and condition, and based on their lifecycle and disutility risk for each distinct limit-states of performance as discussed in the following. In this paper writers attempt to offer a perspective for asset management of civil infrastructures with a focus on highway bridges and describe the tools that are considered necessary for rectifying the current shortcomings mainly arising from subjective and incomplete performance and condition evaluation practice. The adoption of sensing systems, which allows measurements of displacement, acceleration, strain, tilt and that can be collected wirelessly, has the potential of providing objective metrics needed for optimal asset management. The authors however caution that such a transition (from asset management based on visual inspection to data-driven asset management based on objective metrics) could be truly achieved only if combined with the proper training of a new generation of infrastructure inspectors and stakeholders. The paper attempts to provide a roadmap to achieve such a transition in asset management and describes the critical concepts that should be incorporated in training a new generation of civil engineers in charge of maintaining our transportation assets

Non-Contact bridge deflection measurement : application of laser Technology

Structural deflections represent a critical response parameter often measured for structural health monitoring. Traditional measurement sensor technologies such as DCDTs, LVDTs, etc., require attaching the device between the point of measurement and a reference point. Generally, this requires connecting the sensor to the ground or a temporary structure such as scaffolding. Use of the traditional sensors for highway bridge deflection measurement poses many challenges as most of them are over either a road or a waterway. Because of these challenges, they are not often used and deflection is calculated either from indirect data such as girder end rotation or the structural parameters that contribute to deflection which is derived from measurements such as strain and curvature. Strictly speaking, measured displacements provide the best means for understanding structural behavior. Aiming at addressing the challenges of direct measurements of bridge deflections, this article will address the capabilities of two state-of-the-art non-contact measurement technologies. These technologies are: Laser Tracker and Laser Scanner. Laser Tracker records position coordinates at few discrete points while the laser scanner captures point clouds representing deformed and undeformed shapes of a structure. These two remote technologies present distinctive advantages, capabilities, limitations, and several challenges for field applications. The article will present a case study where laser tracker and laser scanner was collaboratively used to measure the deflection of a highway bridge under static truck loads. Further, the capabilities, limitations, and several challenges for field applications of these technologies will be summarized

Evaluation of the quality of ambient vibration monitoring data from the Henry Hudson bridge

Nonintrusive Inspection, Structures Monitoring, and Smart Systems for Homeland Security, Feb 27-28 2006, v.6178: pp. 617803. http://dx.doi.org/10.1117/12.661272The quality of test data is an important consideration in conducting field experiments on civil infrastructure. In addition to possible errors due to the experimental setup, the uncertainties due to incomplete knowledge of a structure’s behavior and its interactions with the natural environment greatly affect the reliability of the system identification results. This paper discusses the uncertainties related to ambient vibration testing of a long-span steel arch bridge and possible ways to mitigate them. The consistency of the identified parameters is examined through statistical analyses

Evaluation of the quality of ambient vibration monitoring data from the Henry Hudson bridge

Nonintrusive Inspection, Structures Monitoring, and Smart Systems for Homeland Security, Feb 27-28 2006, v.6178: pp. 617803. http://dx.doi.org/10.1117/12.661272The quality of test data is an important consideration in conducting field experiments on civil infrastructure. In addition to possible errors due to the experimental setup, the uncertainties due to incomplete knowledge of a structure’s behavior and its interactions with the natural environment greatly affect the reliability of the system identification results. This paper discusses the uncertainties related to ambient vibration testing of a long-span steel arch bridge and possible ways to mitigate them. The consistency of the identified parameters is examined through statistical analyses

Microparticles from patients with metabolic syndrome induce vascular hypo-reactivity via Fas/Fas-ligand pathway in mice

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