18 research outputs found
Diagnosing sputum/smear-negative pulmonary tuberculosis: Does fibre-optic bronchoscopy play a significant role?
No full textBackground : Diagnosis of sputum/smear-negative pulmonary tuberculosis patients can be both challenging and time consuming with many patients being put on empirical anti-tubercular treatment. Fibreoptic bronchoscopy may provide a confirmative and early diagnosis in such patients. Aims: To assess the role of fibreoptic bronchoscopy in the diagnosis of sputum /smear-negative pulmonary tuberculosis. Materials and Methods: The study was conducted on 75 suspected sputum / smear-negative pulmonary tuberculosis cases attending Pulmonary Medicine Department of Mamata Medical College and Hospital, Khammam, AP. Fibreoptic bronchoscopy was performed; culture of sputum and bronchial washings for Mycobacterium tuberculosis was done by BACTEC method. Results: A final diagnosis of sputum /smear-negative pulmonary tuberculosis was made in 60 patients. Bronchial washings smear for acid-fast bacilli (AFB) was positive in 21 patients while culture of bronchial washings was positive in 39 patients. In 29 patients, smear or culture of bronchial washing alone contributed to the final diagnosis. Total yield of bronchoscopy in diagnosis of sputum smear negative pulmonary tuberculosis was 83.33% (50/60); bronchoscopy was the only diagnostic method in 66% cases (40/60) with bronchial washings being the only diagnostic method in 48.33%. Bronchial washings smear for AFB and histopathological evidence of caseating granuloma made immediate diagnosis possible in 48.33% (29/60) patients. Conclusion: Our study suggests that fibreoptic bronchoscopy can provide excellent material for diagnosis of suspected cases of Pulmonary Tuberculosis in whom smears of expectorated sputum do not reveal mycobacteria
The 2005 Chios Ancient Shipwreck Survey: New Methods for Underwater Archaeology
No full textIn 2005 a Greek and American interdisciplinary team investigated two shipwrecks off the coast of Chios dating to the 4th-century b.c. and the 2nd/1st century. The project pioneered archaeological methods of precision acoustic, digital image, and chemical survey using an autonomous underwater vehicle (AUV) and in-situ sensors, increasing the speed of data acquisition while decreasing costs. The AUV recorded data revealing the physical dimensions, age, cargo, and preservation of the wrecks. The earlier wreck contained more than 350 amphoras, predominantly of Chian type, while the Hellenistic wreck contained about 40 Dressel 1C amphoras. Molecular biological analysis of two amphoras from the 4th-century wreck revealed ancient DNA of olive, oregano, and possibly mastic, part of a cargo outbound from Chios.
Author(s): Brendan P. Foley 1 | Katerina Dellaporta 2 | Dimitris Sakellariou 3 | Brian S. Bingham 4 | Richard Camilli 5 | Ryan M. Eustice 6 | Dionysis Evagelistis 7 | Vicki Lynn Ferrini 8 | Kostas Katsaros 9 | Dimitris Kourkoumelis 10 | Aggelos Mallios 11 | Paraskevi Micha 12 | David A. Mindell 13 | Christopher Roman 14 | Hanumant Singh 15 | David S. Switzer 16 | Theotokis Theodoulou 17Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86047/1/bfoley-11.pd
Asymptomatic metalloptysis complicating lobectomy in pulmonary aspergilloma – An unusual complication
No full textAbstractRecurrent haemoptysis in pulmonary aspergilloma is an indication for surgical resection of the cavity and removal of the fungus ball, in patients with a sufficient pulmonary function to allow surgery. Use of titanium surgical clips in such cardiothoracic surgical procedures may be the source of unusual complications. We report one such unusual complication of expectoration of a titanium surgical clip through a right lobectomy stump, the procedure having been performed six years previously for a symptomatic aspergilloma. We believe this to be first instance of metalloptysis in a case of pulmonary aspergilloma, following lobectomy
Map building fusing acoustic and visual information using autonomous underwater vehicles
No full textAuthor Posting. © The Author(s), 2012. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Journal of Field Robotics 30 (2013): 763–783, doi:10.1002/rob.21473.We present a system for automatically building 3-D maps of underwater terrain fusing
visual data from a single camera with range data from multibeam sonar. The six-degree
of freedom location of the camera relative to the navigation frame is derived as part of the
mapping process, as are the attitude offsets of the multibeam head and the on-board velocity
sensor. The system uses pose graph optimization and the square root information smoothing
and mapping framework to simultaneously solve for the robot’s trajectory, the map, and
the camera location in the robot’s frame. Matched visual features are treated within the
pose graph as images of 3-D landmarks, while multibeam bathymetry submap matches are
used to impose relative pose constraints linking robot poses from distinct tracklines of the
dive trajectory. The navigation and mapping system presented works under a variety of
deployment scenarios, on robots with diverse sensor suites. Results of using the system to
map the structure and appearance of a section of coral reef are presented using data acquired
by the Seabed autonomous underwater vehicle.The work described herein was funded by the National Science Foundation Censsis ERC under grant number
EEC-9986821, and by the National Oceanic and Atmospheric Administration under grant number
NA090AR4320129
Applications of geo-referenced underwater photo mosaics in marine biology and archaeology
No full textAuthor Posting. © Oceanography Society, 2007. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 20, 4 (2007): 140-149.In deep water, below the photic zone, still and video
imaging of the seabed requires artificial lighting. Light absorption
and backscatter caused by typical seawater components,
such as dissolved organic matter, plankton, and inorganic particles,
often limit the artificially lit area to a few square meters.
To obtain high-resolution photographic data of larger seabed
areas, a series of images can be compiled into a photo mosaic.
Image mosaics are easier to interpret, communicate, and
exhibit than video footage or a series of images, because the
individual image frames in a photo mosaic are naturally represented
in a spatial context
Component-driven computational design of complex engineering systems.
No full textDuring the conceptual design of complex systems, architects study a number of different options, which comprise the architectural design space. Usually, new system architectures (SAs) are created by modifying existing ones, e.g., by deleting existing and/or adding new elements. Once the concept is synthesised, the architect wishes to swiftly find the effect of the proposed architectural changes at system level. This would involve sizing of the modified sub-systems, and then, obtaining the system level performance. In turn, this involves time-consuming activities, such as re-arrangement (orchestration)
of computational tasks and models. Also, depending on the results, the architect may undertake further modifications. When doing this, a means to navigate across the RFLP (Requirements-Functional-Logical-Physical) views of the SA may be required, in order to trace elements affected by these modifications. Generally, several iterations are involved between architecting and sizing during conceptual design, which, if manually performed, result in a tedious and time-consuming process. There are existing methods which address this problem, but these have significant limitations in that they are usually system specific and often involve an excessive amount of time-consuming manual tasks.
Within this context, the research aim is to improve the efficiency of the architectural design space exploration (ADSE) process, by automating repetitive computational tasks, thus enabling the designer to swiftly and interactively explore multiple SA options.
A novel method, comprised of two parts, has been developed to achieve the aim. In the first part, a graph-theoretic approach is employed to enable architectural element dependency analysis. Here, the relationships between the architectural elements are stored as a graph. Algorithms, such as ‘Depth First Search’ and ‘Transitive Closure’ are then applied to assist the architect in tracing the dependencies between elements that might be affected by a proposed change to other elements of the SA.
In the second part, the architecture is assessed to find the system level performance. The inputs needed for rapid assessment include the functional and logical views of the SA, and the requisite steady-state computational models associated with each of the ‘logical’ components. The assessment process itself consists of three steps. In the first step, the sequence of the sub-systems is automatically generated by extracting a sub-systems source-sink ‘Dependency Structure Matrix (DSM)’ from the logical view, followed by the application of an algorithm which determines the systems’ sizing sequence. In the second step, the individual sub-systems and system level workflows are constructed. Here, the computational workflow (a network of computational models) is represented
as a bipartite graph. A maximum matching enumeration algorithm is used to find all possible workflows for a given model set, and another algorithm, to choose from these the most computationally efficient one, i.e., the workflow with the lowest number of reversed variables. In the third step, the workflows produced in the second step and subsystems ’sizing sequence obtained in the first step are combined to produce a complete workflow.
To demonstrate and evaluate the proposed enablers, the author developed a prototype object-oriented architecting tool. The enablers were individually and collectively verified on representative test-cases. Comparison with the existing methods confirmed the claimed advantages of the proposed approach, namely, reducing the number of manual activities, which results in swifter and interactive ADSE process. Feedback obtained from experts in the aircraft industry during an initial qualitative evaluation session confirmed the usefulness of the proposed method.PhD in Aerospac
Review on Different Searchable Encryption Schemes for Cloud Computing
No full textHeavily available online data and its day to day expansion is need to be focus to store and retrieve it properly. This enforces the data owners tend to store their data into the cloud. This also suggest to handle the data properly and so release the burden of data storage and maintenance. But as the data owner and user, cloud server are not belong to same trusted domain, this may cause the outsourced to the risk. This enforce us to set the policy to avoid such risk factor. This gives us study scope to fine the different techniques to overcome such issue observed by different author. In this paper we try to underline the different solution, its limitation and results they achieved for retrieval of data securely and within less time. Definitely from this we will be able to propose our own solution
Estimating early-winter Antarctic sea ice thickness from deformed ice morphology
No full text© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Mei, M. J., Maksym, T., Weissling, B., & Singh, H. Estimating early-winter Antarctic sea ice thickness from deformed ice morphology. Cryosphere, 13(11), (2019): 2915-2934, doi: 10.5194/tc-13-2915-2019.Satellites have documented variability in sea ice areal extent for decades, but there are significant challenges in obtaining analogous measurements for sea ice thickness data in the Antarctic, primarily due to difficulties in estimating snow cover on sea ice. Sea ice thickness (SIT) can be estimated from snow freeboard measurements, such as those from airborne/satellite lidar, by assuming some snow depth distribution or empirically fitting with limited data from drilled transects from various field studies. Current estimates for large-scale Antarctic SIT have errors as high as ∼50 %, and simple statistical models of small-scale mean thickness have similarly high errors. Averaging measurements over hundreds of meters can improve the model fits to existing data, though these results do not necessarily generalize to other floes. At present, we do not have algorithms that accurately estimate SIT at high resolutions. We use a convolutional neural network with laser altimetry profiles of sea ice surfaces at 0.2 m resolution to show that it is possible to estimate SIT at 20 m resolution with better accuracy and generalization than current methods (mean relative errors ∼15 %). Moreover, the neural network does not require specification of snow depth or density, which increases its potential applications to other lidar datasets. The learned features appear to correspond to basic morphological features, and these features appear to be common to other floes with the same climatology. This suggests that there is a relationship between the surface morphology and the ice thickness. The model has a mean relative error of 20 % when applied to a new floe from the region and season. This method may be extended to lower-resolution, larger-footprint data such as such as Operation IceBridge, and it suggests a possible avenue to reduce errors in satellite estimates of Antarctic SIT from ICESat-2 over current methods, especially at smaller scales.This work was supported by the U.S. National Science Foundation (grant nos. ANT-1341606, ANT-1142075 and ANT-1341717) and NASA (grant no. NNX15AC69G)
Detection of unanticipated faults for autonomous underwater vehicles using online topic models
No full text© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of Field Robotics 35 (2018): 705-716, doi:10.1002/rob.21771.For robots to succeed in complex missions, they must be reliable in the face of subsystem failures and environmental challenges. In this paper, we focus on autonomous underwater vehicle (AUV) autonomy as it pertains to self‐perception and health monitoring, and we argue that automatic classification of state‐sensor data represents an important enabling capability. We apply an online Bayesian nonparametric topic modeling technique to AUV sensor data in order to automatically characterize its performance patterns, then demonstrate how in combination with operator‐supplied semantic labels these patterns can be used for fault detection and diagnosis by means of a nearest‐neighbor classifier. The method is evaluated using data collected by the Monterey Bay Aquarium Research Institute's Tethys long‐range AUV in three separate field deployments. Our results show that the proposed method is able to accurately identify and characterize patterns that correspond to various states of the AUV, and classify faults at a high rate of correct detection with a very low false detection rate.Office of Naval Research Grant Number: N00014‐14‐1‐0199;
David and Lucile Packard Foundatio
Structure and dynamics of a subglacial discharge plume in a Greenlandic fjord
No full textAuthor Posting. © American Geophysical Union, 2016. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 121 (2016): 8670–8688, doi:10.1002/2016JC011764.Discharge of surface-derived meltwater at the submerged base of Greenland's marine-terminating glaciers creates subglacial discharge plumes that rise along the glacier/ocean interface. These plumes impact submarine melting, calving, and fjord circulation. Observations of plume properties and dynamics are challenging due to their proximity to the calving edge of glaciers. Therefore, to date information on these plumes has been largely derived from models. Here we present temperature, salinity, and velocity data collected in a plume that surfaced at the edge of Saqqarliup Sermia, a midsized Greenlandic glacier. The plume is associated with a narrow core of rising waters approximately 20 m in diameter at the ice edge that spreads to a 200 m by 300 m plume pool as it reaches the surface, before descending to its equilibrium depth. Volume flux estimates indicate that the plume is primarily driven by subglacial discharge and that this has been diluted in a ratio of 1:10 by the time the plume reaches the surface. While highly uncertain, meltwater fluxes are likely 2 orders of magnitude smaller than the subglacial discharge flux. The overall plume characteristics agree with those predicted by theoretical plume models for a convection-driven plume with limited influence from submarine melting.National Science Foundation (NSF) Grant Numbers: PLR-1418256 , OCE-1434041;
Woods Hole Oceanographic Institution (WHOI) Ocean and Climate Change Institute (OCCI) Arctic Research Initiative
OCCI;
National Aeronautics and Space Administration Grant Number: NNX10AN83H2017-06-1
