Applications of Advanced, Waveform Based AE Techniques for Testing Composite Materials
NASA Technical Reports Server (NTRS)
Prosser, William H.
1996-01-01
Advanced, waveform based acoustic emission (AE) techniques have been previously used to evaluate damage progression in laboratory tests of composite coupons. In these tests, broad band, high fidelity acoustic sensors were used to detect signals which were then digitized and stored for analysis. Analysis techniques were based on plate mode wave propagation characteristics. This approach, more recently referred to as Modal AE, provides an enhanced capability to discriminate and eliminate noise signals from those generated by damage mechanisms. This technique also allows much more precise source location than conventional, threshold crossing arrival time determination techniques. To apply Modal AE concepts to the interpretation of AE on larger composite structures, the effects of wave propagation over larger distances and through structural complexities must be well characterized and understood. In this research, measurements were made of the attenuation of the extensional and flexural plate mode components of broad band simulated AE signals in large composite panels. As these materials have applications in a cryogenic environment, the effects of cryogenic insulation on the attenuation of plate mode AE signals were also documented.
Acoustic emission studies of large advanced composite rocket motor cases.
NASA Technical Reports Server (NTRS)
Robinson, E. Y.
1973-01-01
Acoustic emission (AE) patterns were measured during pressure testing of advanced composite rocket motor cases made of boron/epoxy and graphite/epoxy. Both accelerometers and high frequency AE transducers were used, and both frequency spectrum and amplitude distribution were studied. The AE patterns suggest that precursor emission might be used in certain cases to anticipate failure. The technique of hold-cycle AE monitoring was also evaluated and could become a valuable decision gate for test continuation/termination. Data presented show similarity of accelerometers and AE transducer responses despite the different frequency response, and suggest that structural AE phenomena are broadband.
Modified Redundancy based Technique—a New Approach to Combat Error Propagation Effect of AES
NASA Astrophysics Data System (ADS)
Sarkar, B.; Bhunia, C. T.; Maulik, U.
2012-06-01
Advanced encryption standard (AES) is a great research challenge. It has been developed to replace the data encryption standard (DES). AES suffers from a major limitation of error propagation effect. To tackle this limitation, two methods are available. One is redundancy based technique and the other one is bite based parity technique. The first one has a significant advantage of correcting any error on definite term over the second one but at the cost of higher level of overhead and hence lowering the processing speed. In this paper, a new approach based on the redundancy based technique is proposed that would certainly speed up the process of reliable encryption and hence the secured communication.
Sanders, Christine C.; Peyret, Michel; Moland, Ellen Smith; Shubert, Carole; Thomson, Kenneth S.; Boeufgras, Jean-Marc; Sanders, W. Eugene
2000-01-01
The Advanced Expert System (AES) was used in conjunction with the VITEK 2 automated antimicrobial susceptibility test system to ascertain the β-lactam phenotypes of 196 isolates of the family Enterobacteriaceae and the species Pseudomonas aeruginosa. These isolates represented a panel of strains that had been collected from laboratories worldwide and whose β-lactam phenotypes had been characterized by biochemical and molecular techniques. The antimicrobial susceptibility of each isolate was determined with the VITEK 2 instrument, and the results were analyzed with the AES to ascertain the β-lactam phenotype. The results were then compared to the β-lactam resistance mechanism determined by biochemical and molecular techniques. Overall, the AES was able to ascertain a β-lactam phenotype for 183 of the 196 (93.4%) isolates tested. For 111 of these 183 (60.7%) isolates, the correct β-lactam phenotype was identified definitively in a single choice by the AES, while for an additional 46 isolates (25.1%), the AES identified the correct β-lactam phenotype provisionally within two or more choices. For the remaining 26 isolates (14.2%), the β-lactam phenotype identified by the AES was incorrect. However, for a number of these isolates, the error was due to remediable problems. These results suggest that the AES is capable of accurate identification of the β-lactam phenotypes of gram-negative isolates and that certain modifications can improve its performance even further. PMID:10655347
NASA Astrophysics Data System (ADS)
Anees, Amir; Khan, Waqar Ahmad; Gondal, Muhammad Asif; Hussain, Iqtadar
2013-07-01
The aim of this work is to make use of the mean of absolute deviation (MAD) method for the evaluation process of substitution boxes used in the advanced encryption standard. In this paper, we use the MAD technique to analyze some popular and prevailing substitution boxes used in encryption processes. In particular, MAD is applied to advanced encryption standard (AES), affine power affine (APA), Gray, Lui J., Residue Prime, S8 AES, SKIPJACK, and Xyi substitution boxes.
A high performance hardware implementation image encryption with AES algorithm
NASA Astrophysics Data System (ADS)
Farmani, Ali; Jafari, Mohamad; Miremadi, Seyed Sohrab
2011-06-01
This paper describes implementation of a high-speed encryption algorithm with high throughput for encrypting the image. Therefore, we select a highly secured symmetric key encryption algorithm AES(Advanced Encryption Standard), in order to increase the speed and throughput using pipeline technique in four stages, control unit based on logic gates, optimal design of multiplier blocks in mixcolumn phase and simultaneous production keys and rounds. Such procedure makes AES suitable for fast image encryption. Implementation of a 128-bit AES on FPGA of Altra company has been done and the results are as follow: throughput, 6 Gbps in 471MHz. The time of encrypting in tested image with 32*32 size is 1.15ms.
NASA Technical Reports Server (NTRS)
Guarnieri, Fernando L.; Tsurutani, Bruce T.; Hajra, Rajkumar; Echer, Ezequiel; Gonzalez, Walter D.; Mannucci, Anthony J.
2014-01-01
High speed solar wind streams cause geomagnetic activity at Earth. In this study we have applied a wavelet interactive filtering and reconstruction technique on the solar wind magnetic field components and AE index series to allowed us to investigate the relationship between the two. The IMF Bz component was found as the most significant solar wind parameter responsible by the control of the AE activity. Assuming magnetic reconnection associated to southward directed Bz is the main mechanism transferring energy into the magnetosphere, we adjust parameters to forecast the AE index. The adjusted routine is able to forecast AE, based only on the Bz measured at the L1 Lagrangian point. This gives a prediction approximately 30-70 minutes in advance of the actual geomagnetic activity. The correlation coefficient between the observed AE data and the forecasted series reached values higher than 0.90. In some cases the forecast reproduced particularities observed in the signal very well.The high correlation values observed and the high efficacy of the forecasting can be taken as a confirmation that reconnection is the main physical mechanism responsible for the energy transfer during HILDCAAs. The study also shows that the IMF Bz component low frequencies are most important for AE prediction.
Theobald, P D; Esward, T J; Dowson, S P; Preston, R C
2005-03-01
Acoustic emission (AE) is a widely used technique that has been employed for the integrity testing of a range of vessels and structures for many years. The last decade has seen advances in signal processing, such that the reliability of AE technology is now being recognised by a wider range of industries. Furthermore, the need for quality control at the manufacturing stage, and requirements of in-service testing, is encouraging the issue of traceable measurements to be addressed. Currently, no independent calibration service for acoustic emission transducers is available within Europe. The UKs National Physical Laboratory (NPL) is undertaking work to develop a measurement facility for the traceable calibration of AE sensors. Such calibrations can contribute to greater acceptance of AE techniques in general, by meeting quality system and other traceability requirements. In this paper the key issues surrounding the development of such a facility are reviewed, including the need to establish repeatable AE sources, select suitable test blocks and to understand the limitations imposed by AE sensors themselves. To provide an absolute measurement of the displacement on the surface of a test block, laser interferometry is employed. In this way the output voltage of an AE sensor can be directly related to the displacement detected at the block surface. A possible calibration methodology is discussed and preliminary calibration results are presented for a commercially available AE sensor, showing its response to longitudinal wave modes.
Ruiz, Janelle Nicole; Belum, Viswanath Reddy; Creel, Patricia; Cohn, Allen; Ewer, Michael; Lacouture, Mario E
2014-10-01
Oncologists treating patients with targeted therapies encounter adverse events (AEs) that pose management challenges, lead to dosing inconsistencies, and impact patient quality of life. Oncologists' practices and attitudes in the management of targeted therapy-related AEs in patients with renal cell carcinoma (RCC) are poorly understood. We sought to identify unmet needs associated with AE management and understand oncologists' treatment optimization strategies. A 24-item online survey was administered in August 2012 to 119 US oncologists treating patients with advanced RCC. The survey solicited responses regarding demographics, practice settings, AE management practice patterns and beliefs, treatment barriers, and patient education. Respondents indicated that between 25% and 50% of patients require dose modification/discontinuation because of AEs. The greatest barrier to optimizing treatment for RCC is the unpredictability of patient responses to treatment (43%). Most respondents (78%) discuss AE management with patients, but only a minority of them proactively reach out to patients (46%). Most practitioners (70%) refer patients to nononcology specialists when faced with unfamiliar AEs, although finding interested physicians (43%) and time constraints (40%) were the most commonly cited barriers to consulting with other specialties. Results suggest that many patients require dose modification/discontinuation because of AEs and that nononcologists are a frequently utilized resource to manage these events. There is a need for predictive drug toxicity markers to establish counseling and prevention, along with opportunities for increased education on supportive care techniques to maintain health-related quality of life and consistent dosing. Copyright © 2014 Elsevier Inc. All rights reserved.
Energy efficiency analysis and implementation of AES on an FPGA
NASA Astrophysics Data System (ADS)
Kenney, David
The Advanced Encryption Standard (AES) was developed by Joan Daemen and Vincent Rjimen and endorsed by the National Institute of Standards and Technology in 2001. It was designed to replace the aging Data Encryption Standard (DES) and be useful for a wide range of applications with varying throughput, area, power dissipation and energy consumption requirements. Field Programmable Gate Arrays (FPGAs) are flexible and reconfigurable integrated circuits that are useful for many different applications including the implementation of AES. Though they are highly flexible, FPGAs are often less efficient than Application Specific Integrated Circuits (ASICs); they tend to operate slower, take up more space and dissipate more power. There have been many FPGA AES implementations that focus on obtaining high throughput or low area usage, but very little research done in the area of low power or energy efficient FPGA based AES; in fact, it is rare for estimates on power dissipation to be made at all. This thesis presents a methodology to evaluate the energy efficiency of FPGA based AES designs and proposes a novel FPGA AES implementation which is highly flexible and energy efficient. The proposed methodology is implemented as part of a novel scripting tool, the AES Energy Analyzer, which is able to fully characterize the power dissipation and energy efficiency of FPGA based AES designs. Additionally, this thesis introduces a new FPGA power reduction technique called Opportunistic Combinational Operand Gating (OCOG) which is used in the proposed energy efficient implementation. The AES Energy Analyzer was able to estimate the power dissipation and energy efficiency of the proposed AES design during its most commonly performed operations. It was found that the proposed implementation consumes less energy per operation than any previous FPGA based AES implementations that included power estimations. Finally, the use of Opportunistic Combinational Operand Gating on an AES cipher was found to reduce its dynamic power consumption by up to 17% when compared to an identical design that did not employ the technique.
A Novel Byte-Substitution Architecture for the AES Cryptosystem.
Hossain, Fakir Sharif; Ali, Md Liakot
2015-01-01
The performance of Advanced Encryption Standard (AES) mainly depends on speed, area and power. The S-box represents an important factor that affects the performance of AES on each of these factors. A number of techniques have been presented in the literature, which have attempted to improve the performance of the S-box byte-substitution. This paper proposes a new S-box architecture, defining it as ultra low power, robustly parallel and highly efficient in terms of area. The architecture is discussed for both CMOS and FPGA platforms, and the pipelined architecture of the proposed S-box is presented for further time savings and higher throughput along with higher hardware resources utilization. A performance analysis and comparison of the proposed architecture is also conducted with those achieved by the existing techniques. The results of the comparison verify the outperformance of the proposed architecture in terms of power, delay and size.
A Novel Byte-Substitution Architecture for the AES Cryptosystem
Hossain, Fakir Sharif; Ali, Md. Liakot
2015-01-01
The performance of Advanced Encryption Standard (AES) mainly depends on speed, area and power. The S-box represents an important factor that affects the performance of AES on each of these factors. A number of techniques have been presented in the literature, which have attempted to improve the performance of the S-box byte-substitution. This paper proposes a new S-box architecture, defining it as ultra low power, robustly parallel and highly efficient in terms of area. The architecture is discussed for both CMOS and FPGA platforms, and the pipelined architecture of the proposed S-box is presented for further time savings and higher throughput along with higher hardware resources utilization. A performance analysis and comparison of the proposed architecture is also conducted with those achieved by the existing techniques. The results of the comparison verify the outperformance of the proposed architecture in terms of power, delay and size. PMID:26491967
Could Acoustic Emission Testing Show a Pipe Failure in Advance?
NASA Astrophysics Data System (ADS)
Soares, S. D.; Teixeira, J. C. G.
2004-02-01
During the last 20 years PETROBRAS has been attempting to use Acoustic Emission (AE) as an inspection tool. In this period the AE concept has changed from a revolutionary method to a way of finding areas to make a complete inspection. PETROBRAS has a lot of pressure vessels inspected by AE and with other NDTs techniques to establish their relationship. In other hand, PETROBRAS R&D Center has conducted destructive hydrostatic tests in pipelines samples with artificial defects made by milling. Those tests were monitored by acoustic emission and manual ultrasonic until the complete failure of pipe sample. This article shows the results obtained and a brief proposal of analysis criteria for this environment of test.
Meeting the security requirements of electronic medical records in the ERA of high-speed computing.
Alanazi, H O; Zaidan, A A; Zaidan, B B; Kiah, M L Mat; Al-Bakri, S H
2015-01-01
This study has two objectives. First, it aims to develop a system with a highly secured approach to transmitting electronic medical records (EMRs), and second, it aims to identify entities that transmit private patient information without permission. The NTRU and the Advanced Encryption Standard (AES) cryptosystems are secured encryption methods. The AES is a tested technology that has already been utilized in several systems to secure sensitive data. The United States government has been using AES since June 2003 to protect sensitive and essential information. Meanwhile, NTRU protects sensitive data against attacks through the use of quantum computers, which can break the RSA cryptosystem and elliptic curve cryptography algorithms. A hybrid of AES and NTRU is developed in this work to improve EMR security. The proposed hybrid cryptography technique is implemented to secure the data transmission process of EMRs. The proposed security solution can provide protection for over 40 years and is resistant to quantum computers. Moreover, the technique provides the necessary evidence required by law to identify disclosure or misuse of patient records. The proposed solution can effectively secure EMR transmission and protect patient rights. It also identifies the source responsible for disclosing confidential patient records. The proposed hybrid technique for securing data managed by institutional websites must be improved in the future.
A Secure Test Technique for Pipelined Advanced Encryption Standard
NASA Astrophysics Data System (ADS)
Shi, Youhua; Togawa, Nozomu; Yanagisawa, Masao; Ohtsuki, Tatsuo
In this paper, we presented a Design-for-Secure-Test (DFST) technique for pipelined AES to guarantee both the security and the test quality during testing. Unlike previous works, the proposed method can keep all the secrets inside and provide high test quality and fault diagnosis ability as well. Furthermore, the proposed DFST technique can significantly reduce test application time, test data volume, and test generation effort as additional benefits.
Waveform Based Acoustic Emission Detection and Location of Matrix Cracking in Composites
NASA Technical Reports Server (NTRS)
Prosser, W. H.
1995-01-01
The operation of damage mechanisms in a material or structure under load produces transient acoustic waves. These acoustic waves are known as acoustic emission (AE). In composites they can be caused by a variety of sources including matrix cracking, fiber breakage, and delamination. AE signals can be detected and analyzed to determine the location of the acoustic source by triangulation. Attempts are also made to analyze the signals to determine the type and severity of the damage mechanism. AE monitoring has been widely used for both laboratory studies of materials, and for testing the integrity of structures in the field. In this work, an advanced, waveform based AE system was used in a study of transverse matrix cracking in cross-ply graphite/epoxy laminates. This AE system featured broad band, high fidelity sensors, and high capture rate digital acquisition and storage of acoustic signals. In addition, analysis techniques based on plate wave propagation models were employed. These features provided superior source location and noise rejection capabilities.
Chemical information obtained from Auger depth profiles by means of advanced factor analysis (MLCFA)
NASA Astrophysics Data System (ADS)
De Volder, P.; Hoogewijs, R.; De Gryse, R.; Fiermans, L.; Vennik, J.
1993-01-01
The advanced multivariate statistical technique "maximum likelihood common factor analysis (MLCFA)" is shown to be superior to "principal component analysis (PCA)" for decomposing overlapping peaks into their individual component spectra of which neither the number of components nor the peak shape of the component spectra is known. An examination of the maximum resolving power of both techniques, MLCFA and PCA, by means of artificially created series of multicomponent spectra confirms this finding unambiguously. Substantial progress in the use of AES as a chemical-analysis technique is accomplished through the implementation of MLCFA. Chemical information from Auger depth profiles is extracted by investigating the variation of the line shape of the Auger signal as a function of the changing chemical state of the element. In particular, MLCFA combined with Auger depth profiling has been applied to problems related to steelcord-rubber tyre adhesion. MLCFA allows one to elucidate the precise nature of the interfacial layer of reaction products between natural rubber vulcanized on a thin brass layer. This study reveals many interesting chemical aspects of the oxi-sulfidation of brass undetectable with classical AES.
Acoustic Emission Analysis of Shuttle Thermal Protection System
NASA Technical Reports Server (NTRS)
Lane, John; Hooker, Jeffery; Immer, Christopher; Walker, James
2004-01-01
Acoustic emission (AE) signals generated from projectile impacts on reinforced and advanced carbon/carbon (RCC and ACC) panels, fired from a compressed-gas gun, identify the type and severity of damage sustained by the target. This type of testing is vital in providing the required "return to flight" (RTF) data needed to ensure continued and safe operation of NASA's Space Shuttle fleet. The gas gun at Kennedy Space Center is capable of propelling 12-inch by 3-inch cylinders of external tank (ET) foam at exit velocities exceeding 1,000 feet per second. Conventional AE analysis techniques require time domain processing of impulse data, along with amplitude distribution analysis. It is well known that identical source excitations can produce a wide range of AE signals amplitudes. In order to satisfy RTF goals, it is necessary to identify impact energy levels above and below damage thresholds. Spectral analysis techniques involving joint time frequency analysis (JTFA) are used to reinforce time domain AE analysis. JTFA analysis of the AE signals consists of short-time Fourier transforms (STFT) and the Huang-Hilbert transform (HHT). The HHT provides a very good measure of the instantaneous frequency of impulse events dominated by a single component. Identifying failure modes and cracking of fibers from flexural and/or extensional mode acoustic signals will help support in-flight as well as postflight impact analysis.
NASA Astrophysics Data System (ADS)
Baccar, D.; Söffker, D.
2017-11-01
Acoustic Emission (AE) is a suitable method to monitor the health of composite structures in real-time. However, AE-based failure mode identification and classification are still complex to apply due to the fact that AE waves are generally released simultaneously from all AE-emitting damage sources. Hence, the use of advanced signal processing techniques in combination with pattern recognition approaches is required. In this paper, AE signals generated from laminated carbon fiber reinforced polymer (CFRP) subjected to indentation test are examined and analyzed. A new pattern recognition approach involving a number of processing steps able to be implemented in real-time is developed. Unlike common classification approaches, here only CWT coefficients are extracted as relevant features. Firstly, Continuous Wavelet Transform (CWT) is applied to the AE signals. Furthermore, dimensionality reduction process using Principal Component Analysis (PCA) is carried out on the coefficient matrices. The PCA-based feature distribution is analyzed using Kernel Density Estimation (KDE) allowing the determination of a specific pattern for each fault-specific AE signal. Moreover, waveform and frequency content of AE signals are in depth examined and compared with fundamental assumptions reported in this field. A correlation between the identified patterns and failure modes is achieved. The introduced method improves the damage classification and can be used as a non-destructive evaluation tool.
NASA Technical Reports Server (NTRS)
Prosser, W. H.; Jackson, K. E.; Kellas, S.; Smith, B. T.; McKeon, J.; Friedman, A.
1995-01-01
Transverse matrix cracking in cross-ply gr/ep laminates was studied with advanced acoustic emission (AE) techniques. The primary goal of this research was to measure the load required to initiate the first transverse matrix crack in cross-ply laminates of different thicknesses. Other methods had been previously used for these measurements including penetrant enhanced radiography, optical microscopy, and audible acoustic microphone measurements. The former methods required that the mechanical test be paused for measurements at load intervals. This slowed the test procedure and did not provide the required resolution in load. With acoustic microphones, acoustic signals from cracks could not be clearly differentiated from other noise sources such as grip damage, specimen slippage, or test machine noise. A second goal for this work was to use the high resolution source location accuracy of the advanced acoustic emission techniques to determine whether the crack initiation site was at the specimen edge or in the interior of the specimen.In this research, advanced AE techniques using broad band sensors, high capture rate digital waveform acquisition, and plate wave propagation based analysis were applied to cross-ply composite coupons with different numbers of 0 and 90 degree plies. Noise signals, believed to be caused by grip damage or specimen slipping, were eliminated based on their plate wave characteristics. Such signals were always located outside the sensor gage length in the gripped region of the specimen. Cracks were confirmed post-test by microscopic analysis of a polished specimen edge, backscatter ultrasonic scans, and in limited cases, by penetrant enhanced radiography. For specimens with three or more 90 degree plies together, there was an exact 1-1 correlation between AE crack signals and observed cracks. The ultrasonic scans and some destructive sectioning analysis showed that the cracks extended across the full width of the specimen. Furthermore, the locations of the cracks from the AE data were in excellent agreement with the locations measured with the microscope. The high resolution source location capability of this technique, combined with an array of sensors, was able to determine that the cracks initiated at the specimen edges, rather than in the interior. For specimens with only one or two 90 degree plies, the crack-like signals were significantly smaller in amplitude and there was not a 1-1 correlation to observed cracks. This was similar to previous results. In this case, however, ultrasonic and destructive sectioning analysis revealed that the cracks did not extend across the specimen. They initiated at the edge, but did not propagate any appreciable distance into the specimen. This explains the much smaller AE signal amplitudes and the difficulty in correlating these signals to actual cracks in this, as well as in the previous study.
NASA Technical Reports Server (NTRS)
Waller, Jess M.; Saulsberry, Regor L.
2009-01-01
This project is a subtask of a multi-center project to advance the state-of-the-art by developing NDE techniques that are capable of evaluating stress rupture (SR) degradation in Kevlar/epoxy (K/Ep) composite overwrapped pressure vessels (COPVs), and damage progression in carbon/epoxy (C/Ep) COPVs. In this subtask, acoustic emission (AE) data acquired during intermittent load hold tensile testing of K/Ep and C/Ep composite tow materials-of-construction used in COPV fabrication were analyzed to monitor progressive damage during the approach to tensile failure. Insight into the progressive damage of composite tow was gained by monitoring AE event rate, energy, source location, and frequency. Source location based on arrival time data was used to discern between significant AE attributable to microstructural damage and spurious AE attributable to background and grip noise. One of the significant findings was the observation of increasing violation of the Kaiser effect (Felicity ratio < 1.0) with damage accumulation.
Continuous acoustic emission monitoring of reinforced concrete under accelerated corrosion
NASA Astrophysics Data System (ADS)
Di Benedetti, M.; Loreto, G.; Nanni, A.; Matta, F.; Gonzalez-Nunez, M. A.
2011-04-01
The development of techniques capable of evaluating deterioration of reinforced concrete (RC) structures is instrumental to the advancement of techniques for the structural health monitoring (SHM) and service life estimate for constructed facilities. One of the main causes leading to degradation of RC is the corrosion of the steel reinforcement. This process can be modeled phenomenologically, while laboratory tests aimed at studying durability responses are typically accelerated in order to provide useful results within a realistic period of time. To assess the condition of damage in RC, a number of nondestructive methods have been recently studied. Acoustic emission (AE) is emerging as a nondestructive tool to detect the onset and progression of deterioration mechanisms. In this paper, the development of accelerated corrosion and continuous AE monitoring test set-up for RC specimens are presented. Relevant information are provided with regard to the characteristics of the corrosion circuit, continuous measurement and acquisition of corrosion potential, selection of AE sensors and AE parameter setting. The effectiveness of the setup in detecting and characterizing the initiation and progression of the corrosion phenomenon is discussed on the basis of preliminary results from small-scale, pre-cracked RC specimens, which are representative of areas near the clear cover in typical RC bridge members.
Damage source identification of reinforced concrete structure using acoustic emission technique.
Panjsetooni, Alireza; Bunnori, Norazura Muhamad; Vakili, Amir Hossein
2013-01-01
Acoustic emission (AE) technique is one of the nondestructive evaluation (NDE) techniques that have been considered as the prime candidate for structural health and damage monitoring in loaded structures. This technique was employed for investigation process of damage in reinforced concrete (RC) frame specimens. A number of reinforced concrete RC frames were tested under loading cycle and were simultaneously monitored using AE. The AE test data were analyzed using the AE source location analysis method. The results showed that AE technique is suitable to identify the sources location of damage in RC structures.
Damage Source Identification of Reinforced Concrete Structure Using Acoustic Emission Technique
Panjsetooni, Alireza; Bunnori, Norazura Muhamad; Vakili, Amir Hossein
2013-01-01
Acoustic emission (AE) technique is one of the nondestructive evaluation (NDE) techniques that have been considered as the prime candidate for structural health and damage monitoring in loaded structures. This technique was employed for investigation process of damage in reinforced concrete (RC) frame specimens. A number of reinforced concrete RC frames were tested under loading cycle and were simultaneously monitored using AE. The AE test data were analyzed using the AE source location analysis method. The results showed that AE technique is suitable to identify the sources location of damage in RC structures. PMID:23997681
Scott, T W; Clark, G G; Lorenz, L H; Amerasinghe, P H; Reiter, P; Edman, J D
1993-01-01
We evaluated a histologic technique for its usefulness in detecting multiple blood feeding by Aedes aegypti (L.) in a single gonotrophic cycle. To standardize the procedure, we carried out a laboratory study in which 166 mosquitoes imbibed two blood meals at known intervals. Eighty percent (78/98) of the multiple meals were detected when the interval between meals was from 1 to < to = 24 h and the time from the second meal to fixation ranged from 0 to 12 hr. At intervals outside this range, only 34% (23/68) of the multiple meals were detected. Overall, 61% (101/166) of the double meals were detected. Examination of 96 engorged Ae. aegypti collected by aspiration from inside houses in San Juan, Puerto Rico, indicated that 50% had imbibed multiple meals. Most wild-caught mosquitoes took their last meal the day before capture, and most multiple feeders fed twice on consecutive days. A dark line of digested blood, or heme, around the first meal and a physical separation between meals were the most useful histologic parameters for detecting multiple feeding in wild Ae. aegypti. An association of multiple feeding with advanced stages of oocyte development suggests that, at the time of collection, most Ae. aegypti from the study site had fed twice in each gonotrophic cycle. We conclude that, although it is labor intensive, histologic examination is an appropriate technique for a longitudinal, community-wide survey of multiple feeding by Ae. aegypti.
The signatures of acoustic emission waveforms from fatigue crack advancing in thin metallic plates
NASA Astrophysics Data System (ADS)
Yeasin Bhuiyan, Md; Giurgiutiu, Victor
2018-01-01
The acoustic emission (AE) waveforms from a fatigue crack advancing in a thin metallic plate possess diverse and complex spectral signatures. In this article, we analyze these waveform signatures in coordination with the load level during cyclic fatigue. The advancing fatigue crack may generate numerous AE hits while it grows under fatigue loading. We found that these AE hits can be sorted into various groups based on their AE waveform signatures. Each waveform group has a particular time-domain signal pattern and a specific frequency spectrum. This indicates that each group represents a certain AE event related to the fatigue crack growth behavior. In situ AE-fatigue experiments were conducted to monitor the fatigue crack growth with simultaneous measurement of AE signals, fatigue loading, and optical crack growth measurement. An in situ microscope was installed in the load-frame of the mechanical testing system (MTS) to optically monitor the fatigue crack growth and relate the AE signals with the crack growth measurement. We found the AE signal groups at higher load levels (75%-85% of maximum load) were different from the AE signal groups that happened at lower load levels (below 60% of load level). These AE waveform groups are highly related to the fatigue crack-related AE events. These AE signals mostly contain the higher frequency peaks (100 kHz, 230 kHz, 450 kHz, 550 kHz). Some AE signal groups happened as a clustered form that relates a sequence of small AE events within the fatigue crack. They happened at relatively lower load level (50%-60% of the maximum load). These AE signal groups may be related to crack friction and micro-fracture during the friction process. These AE signals mostly contain the lower frequency peaks (60 kHz, 100 kHz, 200 kHz). The AE waveform based analysis may give us comprehensive information of the metal fatigue.
Changes in Sunken Eyes Combined with Blepharoptosis after Levator Resection.
Mawatari, Yuki; Fukushima, Mikiko; Kawaji, Takahiro
2017-12-01
This study aims to report the changes in sunken eyes combined with blepharoptosis after levator resection. Analysis involved 60 eyes from 32 patients with sunken eyes combined with blepharoptosis. Advancement of the levator aponeurosis and the Müller's muscle complex (levator resection) was performed in these patients. Area of upper eyelid sulcus (AES) was defined as the area of the upper eyelid shadow. The digital images were converted to black and white using image-processing software (Adobe Photoshop), and the AES was calculated using ImageJ software. In addition, margin reflex distance, eyebrow height (EBH), and AES were measured before and 3 months after surgery to assess the changes in the eyelids. Preoperative AES was significantly correlated to age ( P < 0.0001; r = 0.8062). Sunken eyes were remarkably improved after levator resection in all patients. Mean margin reflex distance significantly increased, whereas mean EBH and mean AES significantly decreased at 3 months after surgery ( P < 0.0001). The AES change was significantly correlated to the EBH change ( P < 0.0001; r = 0.5184). The principal aim of levator resection is to improve upper eyelid height and visual fields; however, this technique can alter the location of the eyebrow and upper orbital fat. The effects fill the hollowness of the upper eyelid and can remarkably improve sunken eyes.
NASA Astrophysics Data System (ADS)
Vidya Sagar, R.; Raghu Prasad, B. K.
2012-03-01
This article presents a review of recent developments in parametric based acoustic emission (AE) techniques applied to concrete structures. It recapitulates the significant milestones achieved by previous researchers including various methods and models developed in AE testing of concrete structures. The aim is to provide an overview of the specific features of parametric based AE techniques of concrete structures carried out over the years. Emphasis is given to traditional parameter-based AE techniques applied to concrete structures. A significant amount of research on AE techniques applied to concrete structures has already been published and considerable attention has been given to those publications. Some recent studies such as AE energy analysis and b-value analysis used to assess damage of concrete bridge beams have also been discussed. The formation of fracture process zone and the AE energy released during the fracture process in concrete beam specimens have been summarised. A large body of experimental data on AE characteristics of concrete has accumulated over the last three decades. This review of parametric based AE techniques applied to concrete structures may be helpful to the concerned researchers and engineers to better understand the failure mechanism of concrete and evolve more useful methods and approaches for diagnostic inspection of structural elements and failure prediction/prevention of concrete structures.
Advanced exterior sensor project : final report, September 2004.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ashby, M. Rodema
2004-12-01
This report (1) summarizes the overall design of the Advanced Exterior Sensor (AES) system to include detailed descriptions of system components, (2) describes the work accomplished throughout FY04 to evaluate the current health of the original prototype and to return it to operation, (3) describes the status of the AES and the AES project as of September 2004, and (4) details activities planned to complete modernization of the system to include development and testing of the second-generation AES prototype.
Qu, Yongzhi; He, David; Yoon, Jae; Van Hecke, Brandon; Bechhoefer, Eric; Zhu, Junda
2014-01-01
In recent years, acoustic emission (AE) sensors and AE-based techniques have been developed and tested for gearbox fault diagnosis. In general, AE-based techniques require much higher sampling rates than vibration analysis-based techniques for gearbox fault diagnosis. Therefore, it is questionable whether an AE-based technique would give a better or at least the same performance as the vibration analysis-based techniques using the same sampling rate. To answer the question, this paper presents a comparative study for gearbox tooth damage level diagnostics using AE and vibration measurements, the first known attempt to compare the gearbox fault diagnostic performance of AE- and vibration analysis-based approaches using the same sampling rate. Partial tooth cut faults are seeded in a gearbox test rig and experimentally tested in a laboratory. Results have shown that the AE-based approach has the potential to differentiate gear tooth damage levels in comparison with the vibration-based approach. While vibration signals are easily affected by mechanical resonance, the AE signals show more stable performance. PMID:24424467
NASA Astrophysics Data System (ADS)
Desa, M. S. M.; Ibrahim, M. H. W.; Shahidan, S.; Ghadzali, N. S.; Misri, Z.
2018-04-01
Acoustic emission (AE) technique is one of the non-destructive (NDT) testing, where it can be used to determine the damage of concrete structures such as crack, corrosion, stability, sensitivity, as structure monitoring and energy formed within cracking opening growth in the concrete structure. This article gives a comprehensive review of the acoustic emission (AE) technique testing due to its application in concrete structure for structural health monitoring (SHM). Assessment of AE technique used for structural are reviewed to give the perception of its structural engineering such as dam, bridge and building, where the previous research has been reviewed based on AE application. The assessment of AE technique focusing on basic fundamental of parametric and signal waveform analysis during analysis process and its capability in structural monitoring. Moreover, the assessment and application of AE due to its function have been summarized and highlighted for future references
Applying transpose matrix on advanced encryption standard (AES) for database content
NASA Astrophysics Data System (ADS)
Manurung, E. B. P.; Sitompul, O. S.; Suherman
2018-03-01
Advanced Encryption Standard (AES) is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) and has been adopted by the U.S. government and is now used worldwide. This paper reports the impact of transpose matrix integration to AES. Transpose matrix implementation on AES is aimed at first stage of chypertext modifications for text based database security so that the confidentiality improves. The matrix is also able to increase the avalanche effect of the cryptography algorithm 4% in average.
Campone, Mario; Yang, Hongbo; Faust, Elizabeth; Kageleiry, Andrew; Signorovitch, James E; Zhang, Jie; Gao, Haitao
2014-12-01
Treatment options for recurrent or progressive hormone receptor-positive (HR+) advanced breast cancer include chemotherapy and everolimus plus exemestane (EVE + EXE). This study estimates the costs of managing adverse events (AEs) during EVE + EXE therapy and single-agent chemotherapy in Western Europe. An economic model was developed to estimate the per patient cost of managing grade 3/4 AEs for patients who were treated with EVE + EXE or chemotherapies. AE rates for patients receiving EVE + EXE were collected from the phase III BOLERO-2 trial. AE rates for single-agent chemotherapy, capecitabine, docetaxel, or doxorubicin were collected from published clinical trial data. AEs with at least 2% prevalence for any of the treatments were included in the model. A literature search was conducted to obtain costs of managing each AE, which were then averaged across Western European countries (when available). Per patient costs for managing AEs among patients receiving different therapies were reported in 2012 euros (€). The EVE + EXE combination had the lowest average per patient cost of managing AEs (€730) compared to all chemotherapies during the first year of treatment (doxorubicin: €1230; capecitabine: €1721; docetaxel: €2390). The most costly adverse event among all patients treated with EVE + EXE was anemia (on average €152 per patient). The most costly adverse event among all patients treated with capecitabine, docetaxel, or doxorubicin was lymphocytopenia (€861 per patient), neutropenia (€821 per patient), and leukopenia (€382 per patient), respectively. The current model estimates that AE management during the treatment of HR+ advanced breast cancer will cost one-half to one-third less for EVE + EXE patients than for chemotherapy patients. The consideration of AE costs could have important implications in the context of healthcare spending for advanced breast cancer treatment.
NASA Astrophysics Data System (ADS)
Chen, Ming-Chih; Hsiao, Shen-Fu
In this paper, we propose an area-efficient design of Advanced Encryption Standard (AES) processor by applying a new common-expression-elimination (CSE) method to the sub-functions of various transformations required in AES. The proposed method reduces the area cost of realizing the sub-functions by extracting the common factors in the bit-level XOR/AND-based sum-of-product expressions of these sub-functions using a new CSE algorithm. Cell-based implementation results show that the AES processor with our proposed CSE method has significant area improvement compared with previous designs.
Peterson, Mary E
2013-08-01
Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved for the treatment of advanced renal cell carcinoma, pancreatic neuroendocrine tumors, subependymal giant cell astrocytoma associated with tuberous sclerosis complex, renal angiomyolipoma and tuberous sclerosis complex, and, in combination with exemestane, for hormone receptor-positive HER2-negative advanced breast cancer after failure of treatment with letrozole or anastrozole. Results from the phase III BOLERO-2 trial demonstrated that everolimus in combination with exemestane provided significant clinical benefit to patients with advanced hormone receptor-positive breast cancer. Although everolimus is generally well tolerated, as with most therapies administered in an advanced cancer setting, drug-related adverse events (AEs) inevitably occur. Most common AEs observed in the everolimus studies include stomatitis, rash, infection, noninfectious pneumonitis, and hyperglycemia. Clinical awareness and early identification of such AEs by oncology nurses are essential to dosing (interruptions, reduction, and treatment discontinuation); quality of life; and, ultimately, patient outcomes. Because everolimus has already been shown to significantly improve clinical efficacy in patients with advanced breast cancer, a proactive approach to the practical management of AEs associated with this mTOR inhibitor as well as other most common AEs observed in this patient population has been reviewed and outlined here.
Wang, Zheng; Wang, Shi-Wei; Qiu, De-Ren; Yang, Peng-Yuan
2009-10-01
Advanced ceramics have been applied to various important fields such as information science, aeronautics and astronautics, and life sciences. However, the optics and electric properties of ceramics are significantly affected by the micro and trace impurities existing in the material even at very low concentration level. Thus, the accurate determination of impurities is important for materials preparation and performance. Methodology of the analysis of advanced ceramic materials using ICP-AES/MS was reviewed in the present paper for the past decade. Various techniques of sample introduction, especially advances in the authors' recent work, are described in detail. The developing trend is also presented. Sixty references are cited.
Selected Bibliography on Optimizing Techniques in Statistics
1981-08-01
problems in business, industry and .ogovern nt ae f rmulated as optimization problem. Topics in optimization constitute an essential area of study in...numerical, iii) mathematical programming, and (iv) variational. We provide pertinent references with statistical applications Sin the above areas in Part I...TMS Advanced Studies in Managentnt Sciences, North-Holland PIIENli iiiany, Amsterdam. (To appear.) Spang, H. A. (1962). A review of minimization
Kim, Young-Min; Youn, Chun Song; Kim, Soo Hyun; Lee, Byung Kook; Cho, In Soo; Cho, Gyu Chong; Jeung, Kyung Woon; Oh, Sang Hoon; Choi, Seung Pill; Shin, Jong Hwan; Cha, Kyoung-Chul; Oh, Joo Suk; Yim, Hyeon Woo; Park, Kyu Nam
2015-07-22
The aim of this study was to investigate the association of adverse events (AEs) during targeted temperature management (TTM) and other AEs and concomitant treatments during the advanced critical care period with poor neurological outcome at hospital discharge in adult out-of-hospital cardiac arrest (OHCA) patients. This was a retrospective study using Korean Hypothermia Network registry data of adult OHCA patients treated with TTM in 24 teaching hospitals throughout South Korea from 2007 to 2012. Demographic characteristics, resuscitation and post-resuscitation variables, AEs, and concomitant treatments during TTM and the advanced critical care were collected. The primary outcome was poor neurological outcome, defined as a cerebral performance category (CPC) score of 3-5 at hospital discharge. The AEs and concomitant treatments were individually entered into the best multivariable predictive model of poor neurological outcome to evaluate the associations between each variable and outcome. A total of 930 patients, including 704 for whom a complete dataset of AEs and covariates was available for multivariable modeling, were included in the analysis; 476 of these patients exhibited poor neurological outcome [CPC 3 = 50 (7.1%), CPC 4 = 214 (30.4%), and CPC 5 = 212 (30.1%)]. Common AEs included hyperglycemia (45.6%), hypokalemia (31.3%), arrhythmia (21.3%) and hypotension (29%) during cooling, and hypotension (21.6%) during rewarming. Bleeding (5%) during TTM was a rare AE. Common AEs during the advanced critical care included pneumonia (39.6%), myoclonus (21.9%), seizures (21.7%) and hypoglycemia within 72 hours (23%). After adjusting for independent predictors of outcome, cooling- and rewarming-related AEs were not significantly associated with poor neurological outcome. However, sepsis, myoclonus, seizure, hypoglycemia within 72 hours and anticonvulsant use during the advanced critical care were associated with poor neurological outcome [adjusted odds ratios (95% confidence intervals) of 3.12 (1.40-6.97), 3.72 (1.93-7.16), 4.02 (2.04-7.91), 2.03 (1.09-3.78), and 1.69 (1.03-2.77), respectively]. Alternatively, neuromuscular blocker use was inversely associated with poor neurological outcome (0.48 [0.28-0.84]). Cooling- and rewarming-related AEs were not associated with poor neurological outcome at hospital discharge. Sepsis, myoclonus, seizure, hypoglycemia within 72 hours and anticonvulsant use during the advanced critical care period were associated with poor neurological outcome at hospital discharge in our study.
A framework for the damage evaluation of acoustic emission signals through Hilbert-Huang transform
NASA Astrophysics Data System (ADS)
Siracusano, Giulio; Lamonaca, Francesco; Tomasello, Riccardo; Garescì, Francesca; Corte, Aurelio La; Carnì, Domenico Luca; Carpentieri, Mario; Grimaldi, Domenico; Finocchio, Giovanni
2016-06-01
The acoustic emission (AE) is a powerful and potential nondestructive testing method for structural monitoring in civil engineering. Here, we show how systematic investigation of crack phenomena based on AE data can be significantly improved by the use of advanced signal processing techniques. Such data are a fundamental source of information that can be used as the basis for evaluating the status of the material, thereby paving the way for a new frontier of innovation made by data-enabled analytics. In this article, we propose a framework based on the Hilbert-Huang Transform for the evaluation of material damages that (i) facilitates the systematic employment of both established and promising analysis criteria, and (ii) provides unsupervised tools to achieve an accurate classification of the fracture type, the discrimination between longitudinal (P-) and traversal (S-) waves related to an AE event. The experimental validation shows promising results for a reliable assessment of the health status through the monitoring of civil infrastructures.
NASA Astrophysics Data System (ADS)
Mendoza, Edgar; Prohaska, John; Kempen, Connie; Esterkin, Yan; Sun, Sunjian
2013-05-01
Acoustic emission sensing is a leading structural health monitoring technique use for the early warning detection of structural damage associated with impacts, cracks, fracture, and delaminations in advanced materials. Current AE systems based on electronic PZT transducers suffer from various limitations that prevent its wide dynamic use in practical avionics and aerospace applications where weight, size and power are critical for operation. This paper describes progress towards the development of a wireless in-flight distributed fiber optic acoustic emission monitoring system (FAESense™) suitable for the onboard-unattended detection, localization, and classification of damage in avionics and aerospace structures. Fiber optic AE sensors offer significant advantages over its counterpart electronic AE sensors by using a high-density array of micron-size AE transducers distributed and multiplex over long lengths of a standard single mode optical fiber. Immediate SHM applications are found in commercial and military aircraft, helicopters, spacecraft, wind mil turbine blades, and in next generation weapon systems, as well as in the petrochemical and aerospace industries, civil structures, power utilities, and a wide spectrum of other applications.
Monitoring damage growth in titanium matrix composites using acoustic emission
NASA Technical Reports Server (NTRS)
Bakuckas, J. G., Jr.; Prosser, W. H.; Johnson, W. S.
1993-01-01
The application of the acoustic emission (AE) technique to locate and monitor damage growth in titanium matrix composites (TMC) was investigated. Damage growth was studied using several optical techniques including a long focal length, high magnification microscope system with image acquisition capabilities. Fracture surface examinations were conducted using a scanning electron microscope (SEM). The AE technique was used to locate damage based on the arrival times of AE events between two sensors. Using model specimens exhibiting a dominant failure mechanism, correlations were established between the observed damage growth mechanisms and the AE results in terms of the events amplitude. These correlations were used to monitor the damage growth process in laminates exhibiting multiple modes of damage. Results revealed that the AE technique is a viable and effective tool to monitor damage growth in TMC.
Weinstein, Alyona; Gordon, Ruth-Ann; Kasler, Mary Kate; Burke, Matthew; Ranjan, Smita; Hodgetts, Jackie; Reed, Vanessa; Shames, Yelena; Prempeh-Keteku, Nana; Lingard, Karla
2017-01-01
The immune checkpoint inhibitors ipilimumab, nivolumab, and pembrolizumab represent a substantial improvement in treating advanced melanoma but are associated with adverse events (AEs) likely related to general immunologic enhancement. To ensure that patients receive optimal benefit from these agents, prompt assessment and treatment of AEs are essential. We review the efficacy and safety profiles of these immune checkpoint inhibitors and describe guidelines for managing immune-related AEs. We also present case studies describing the management of toxicities in patients receiving immune checkpoint inhibitor therapy. These cases illustrate the importance of collecting a detailed medical history when administering immunotherapy, as this information is necessary to establish baseline, inform monitoring, and determine the etiology of symptoms. Advanced practice nurses and physician assistants are uniquely positioned to educate patients on the early recognition of AEs and have an important role in establishing appropriate monitoring and open dialogue among services. PMID:29900017
NASA Technical Reports Server (NTRS)
Sargusingh, Miriam J.; Nelson, Jason R.
2014-01-01
NASA has highlighted reliability as critical to future human space exploration, particularly in the area of environmental controls and life support systems. The Advanced Exploration Systems (AES) projects have been encouraged to pursue higher reliability components and systems as part of technology development plans. However, no consensus has been reached on what is meant by improving on reliability, or on how to assess reliability within the AES projects. This became apparent when trying to assess reliability as one of several figures of merit for a regenerable water architecture trade study. In the spring of 2013, the AES Water Recovery Project hosted a series of events at Johnson Space Center with the intended goal of establishing a common language and understanding of NASA's reliability goals, and equipping the projects with acceptable means of assessing the respective systems. This campaign included an educational series in which experts from across the agency and academia provided information on terminology, tools, and techniques associated with evaluating and designing for system reliability. The campaign culminated in a workshop that included members of the Environmental Control and Life Support System and AES communities. The goal of this workshop was to develop a consensus on what reliability means to AES and identify methods for assessing low- to mid-technology readiness level technologies for reliability. This paper details the results of that workshop.
ECLSS Reliability for Long Duration Missions Beyond Lower Earth Orbit
NASA Technical Reports Server (NTRS)
Sargusingh, Miriam J.; Nelson, Jason
2014-01-01
Reliability has been highlighted by NASA as critical to future human space exploration particularly in the area of environmental controls and life support systems. The Advanced Exploration Systems (AES) projects have been encouraged to pursue higher reliability components and systems as part of technology development plans. However there is no consensus on what is meant by improving on reliability; nor on how to assess reliability within the AES projects. This became apparent when trying to assess reliability as one of several figures of merit for a regenerable water architecture trade study. In the spring of 2013, the AES Water Recovery Project (WRP) hosted a series of events at the NASA Johnson Space Center (JSC) with the intended goal of establishing a common language and understanding of our reliability goals, and equipping the projects with acceptable means of assessing our respective systems. This campaign included an educational series in which experts from across the agency and academia provided information on terminology, tools and techniques associated with evalauating and designing for system reliability. The campaign culminated in a workshop at JSC with members of the ECLSS and AES communities with the goal of developing a consensus on what reliability means to AES and identifying methods for assessing our low to mid-technology readiness level (TRL) technologies for reliability. This paper details the results of the workshop.
ECLSS Reliability for Long Duration Missions Beyond Lower Earth Orbit
NASA Technical Reports Server (NTRS)
Sargusingh, Miriam J.; Nelson, Jason
2014-01-01
Reliability has been highlighted by NASA as critical to future human space exploration particularly in the area of environmental controls and life support systems. The Advanced Exploration Systems (AES) projects have been encouraged to pursue higher reliability components and systems as part of technology development plans. However, there is no consensus on what is meant by improving on reliability; nor on how to assess reliability within the AES projects. This became apparent when trying to assess reliability as one of several figures of merit for a regenerable water architecture trade study. In the Spring of 2013, the AES Water Recovery Project (WRP) hosted a series of events at the NASA Johnson Space Center (JSC) with the intended goal of establishing a common language and understanding of our reliability goals and equipping the projects with acceptable means of assessing our respective systems. This campaign included an educational series in which experts from across the agency and academia provided information on terminology, tools and techniques associated with evaluating and designing for system reliability. The campaign culminated in a workshop at JSC with members of the ECLSS and AES communities with the goal of developing a consensus on what reliability means to AES and identifying methods for assessing our low to mid-technology readiness level (TRL) technologies for reliability. This paper details the results of the workshop.
NASA Astrophysics Data System (ADS)
Wang, Wentao; Li, Hui; Qu, Zhi
2012-04-01
Basalt fiber reinforced polymer (BFRP) is a structural material with superior mechanical properties. In this study, unidirectional BFRP laminates with 14 layers are made with the hand lay-up method. Then, the acoustic emission technique (AE) combined with the scanning electronic microscope (SEM) technique is employed to monitor the fatigue damage evolution of the BFRP plates in the fatigue loading tests. Time-frequency analysis using the wavelet transform technique is proposed to analyze the received AE signal instead of the peak frequency method. A comparison between AE signals and SEM images indicates that the multi-frequency peaks picked from the time-frequency curves of AE signals reflect the accumulated fatigue damage evolution and fatigue damage patterns. Furthermore, seven damage patterns, that is, matrix cracking, delamination, fiber fracture and their combinations, are identified from the time-frequency curves of the AE signals.
Fatigue crack sizing in rail steel using crack closure-induced acoustic emission waves
NASA Astrophysics Data System (ADS)
Li, Dan; Kuang, Kevin Sze Chiang; Ghee Koh, Chan
2017-06-01
The acoustic emission (AE) technique is a promising approach for detecting and locating fatigue cracks in metallic structures such as rail tracks. However, it is still a challenge to quantify the crack size accurately using this technique. AE waves can be generated by either crack propagation (CP) or crack closure (CC) processes and classification of these two types of AE waves is necessary to obtain more reliable crack sizing results. As the pre-processing step, an index based on wavelet power (WP) of AE signal is initially established in this paper in order to distinguish between the CC-induced AE waves and their CP-induced counterparts. Here, information embedded within the AE signal was used to perform the AE wave classification, which is preferred to the use of real-time load information, typically adopted in other studies. With the proposed approach, it renders the AE technique more amenable to practical implementation. Following the AE wave classification, a novel method to quantify the fatigue crack length was developed by taking advantage of the CC-induced AE waves, the count rate of which was observed to be positively correlated with the crack length. The crack length was subsequently determined using an empirical model derived from the AE data acquired during the fatigue tests of the rail steel specimens. The performance of the proposed method was validated by experimental data and compared with that of the traditional crack sizing method, which is based on CP-induced AE waves. As a significant advantage over other AE crack sizing methods, the proposed novel method is able to estimate the crack length without prior knowledge of the initial crack length, integration of AE data or real-time load amplitude. It is thus applicable to the health monitoring of both new and existing structures.
Fatigue crack localization with near-field acoustic emission signals
NASA Astrophysics Data System (ADS)
Zhou, Changjiang; Zhang, Yunfeng
2013-04-01
This paper presents an AE source localization technique using near-field acoustic emission (AE) signals induced by crack growth and propagation. The proposed AE source localization technique is based on the phase difference in the AE signals measured by two identical AE sensing elements spaced apart at a pre-specified distance. This phase difference results in canceling-out of certain frequency contents of signals, which can be related to AE source direction. Experimental data from simulated AE source such as pencil breaks was used along with analytical results from moment tensor analysis. It is observed that the theoretical predictions, numerical simulations and the experimental test results are in good agreement. Real data from field monitoring of an existing fatigue crack on a bridge was also used to test this system. Results show that the proposed method is fairly effective in determining the AE source direction in thick plates commonly encountered in civil engineering structures.
Tissue Acoustoelectric Effect Modeling From Solid Mechanics Theory.
Song, Xizi; Qin, Yexian; Xu, Yanbin; Ingram, Pier; Witte, Russell S; Dong, Feng
2017-10-01
The acoustoelectric (AE) effect is a basic physical phenomenon, which underlies the changes made in the conductivity of a medium by the application of focused ultrasound. Recently, based on the AE effect, several biomedical imaging techniques have been widely studied, such as ultrasound-modulated electrical impedance tomography and ultrasound current source density imaging. To further investigate the mechanism of the AE effect in tissue and to provide guidance for such techniques, we have modeled the tissue AE effect using the theory of solid mechanics. Both bulk compression and thermal expansion of tissue are considered and discussed. Computation simulation shows that the muscle AE effect result, conductivity change rate, is 3.26×10 -3 with 4.3-MPa peak pressure, satisfying the theoretical value. Bulk compression plays the main role for muscle AE effect, while thermal expansion makes almost no contribution to it. In addition, the AE signals of porcine muscle are measured at different focal positions. With the same magnitude order and the same change trend, the experiment result confirms that the simulation result is effective. Both simulation and experimental results validate that tissue AE effect modeling using solid mechanics theory is feasible, which is of significance for the further development of related biomedical imaging techniques.
19 CFR 192.14 - Electronic information for outward cargo required in advance of departure.
Code of Federal Regulations, 2014 CFR
2014-04-01
... Information Through the Automated Export System (AES) § 192.14 Electronic information for outward cargo... Automated Export System (AES)). (b) Presentation of data—(1) Time for presenting data. USPPIs or their... regulatory authority to do so. The CBP will also continue to require 72-hour advance notice for used vehicle...
19 CFR 192.14 - Electronic information for outward cargo required in advance of departure.
Code of Federal Regulations, 2013 CFR
2013-04-01
... Information Through the Automated Export System (AES) § 192.14 Electronic information for outward cargo... Automated Export System (AES)). (b) Presentation of data—(1) Time for presenting data. USPPIs or their... regulatory authority to do so. The CBP will also continue to require 72-hour advance notice for used vehicle...
19 CFR 192.14 - Electronic information for outward cargo required in advance of departure.
Code of Federal Regulations, 2012 CFR
2012-04-01
... Information Through the Automated Export System (AES) § 192.14 Electronic information for outward cargo... Automated Export System (AES)). (b) Presentation of data—(1) Time for presenting data. USPPIs or their... regulatory authority to do so. The CBP will also continue to require 72-hour advance notice for used vehicle...
19 CFR 192.14 - Electronic information for outward cargo required in advance of departure.
Code of Federal Regulations, 2011 CFR
2011-04-01
... Information Through the Automated Export System (AES) § 192.14 Electronic information for outward cargo... Automated Export System (AES)). (b) Presentation of data—(1) Time for presenting data. USPPIs or their... regulatory authority to do so. The CBP will also continue to require 72-hour advance notice for used vehicle...
Health diagnosis of arch bridge suspender by acoustic emission technique
NASA Astrophysics Data System (ADS)
Li, Dongsheng; Ou, Jinping
2007-01-01
Conventional non-destructive methods can't be dynamically monitored the suspenders' damage levels and types, so acoustic emission (AE) technique is proposed to monitor its activity. The validity signals are determined by the relationship with risetime and duration. The ambient noise is eliminated using float threshold value and placing a guard sensor. The cement mortar and steel strand damage level is analyzed by AE parameter method and damage types are judged by waveform analyzing technique. Based on these methods, all the suspenders of Sichuan Ebian Dadu river arch bridge have been monitored using AE techniques. The monitoring results show that AE signal amplitude, energy, counts can visually display the suspenders' damage levels, the difference of waveform and frequency range express different damage type. The testing results are well coincide with the practical situation.
Multiple Lookup Table-Based AES Encryption Algorithm Implementation
NASA Astrophysics Data System (ADS)
Gong, Jin; Liu, Wenyi; Zhang, Huixin
Anew AES (Advanced Encryption Standard) encryption algorithm implementation was proposed in this paper. It is based on five lookup tables, which are generated from S-box(the substitution table in AES). The obvious advantages are reducing the code-size, improving the implementation efficiency, and helping new learners to understand the AES encryption algorithm and GF(28) multiplication which are necessary to correctly implement AES[1]. This method can be applied on processors with word length 32 or above, FPGA and others. And correspondingly we can implement it by VHDL, Verilog, VB and other languages.
Investigation of the Flow Physics Driving Stall-Side Flutter in Advanced Forward Swept Fan Designs
NASA Technical Reports Server (NTRS)
Sanders, Albert J.; Liu, Jong S.; Panovsky, Josef; Bakhle, Milind A.; Stefko, George; Srivastava, Rakesh
2003-01-01
Flutter-free operation of advanced transonic fan designs continues to be a challenging task for the designers of aircraft engines. In order to meet the demands of increased performance and lighter weight, these modern fan designs usually feature low-aspect ratio shroudless rotor blade designs that make the task of achieving adequate flutter margin even more challenging for the aeroelastician. This is especially true for advanced forward swept designs that encompass an entirely new design space compared to previous experience. Fortunately, advances in unsteady computational fluid dynamic (CFD) techniques over the past decade now provide an analysis capability that can be used to quantitatively assess the aeroelastic characteristics of these next generation fans during the design cycle. For aeroelastic applications, Mississippi State University and NASA Glenn Research Center have developed the CFD code TURBO-AE. This code is a time-accurate three-dimensional Euler/Navier-Stokes unsteady flow solver developed for axial-flow turbomachinery that can model multiple blade rows undergoing harmonic oscillations with arbitrary interblade phase angles, i.e., nodal diameter patterns. Details of the code can be found in Chen et al. (1993, 1994), Bakhle et al. (1997, 1998), and Srivastava et al. (1999). To assess aeroelastic stability, the work-per-cycle from TURBO-AE is converted to the critical damping ratio since this value is more physically meaningful, with both the unsteady normal pressure and viscous shear forces included in the work-per-cycle calculation. If the total damping (aerodynamic plus mechanical) is negative, then the blade is unstable since it extracts energy from the flow field over the vibration cycle. TURBO-AE is an integral part of an aeroelastic design system being developed at Honeywell Engines, Systems & Services for flutter and forced response predictions, with test cases from development rig and engine tests being used to validate its predictive capability. A recent experimental program (Sanders et al., 2002) was aimed at providing the necessary unsteady aerodynamic and vibratory response data needed to validate TURBO-AE for fan flutter predictions. A comparison of numerical TURBO-AE simulations with the benchmark flutter data is given in Sanders et al. (2003), with the data used to guide the validation of the code and define best practices for performing accurate unsteady simulations. The agreement between the analyses and the predictions was quite remarkable, demonstrating the ability of the analysis to accurately model the unsteady flow processes driving stall-side flutter.
Assessment of the integrity of concrete bridge structures by acoustic emission technique
NASA Astrophysics Data System (ADS)
Yoon, Dong-Jin; Park, Philip; Jung, Juong-Chae; Lee, Seung-Seok
2002-06-01
This study was aimed at developing a new method for assessing the integrity of concrete structures. Especially acoustic emission technique was used in carrying out both laboratory experiment and field application. From the previous laboratory study, we confirmed that AE analysis provided a promising approach for estimating the level of damage and distress in concrete structures. The Felicity ratio, one of the key parameter for assessing damage, exhibits a favorable correlation with the overall damage level. The total number of AE events under stepwise cyclic loading also showed a good agreement with the damage level. In this study, a new suggested technique was applied to several concrete bridges in Korea in order to verify the applicability in field. The AE response was analyzed to obtain key parameters such as the total number and rate of AE events, AE parameter analysis for each event, and the characteristic features of the waveform as well as Felicity ratio analysis. Stepwise loading-unloading procedure for AE generation was introduced in field test by using each different weight of vehicle. According to the condition of bridge, for instance new or old bridge, AE event rate and AE generation behavior indicated many different aspects. The results showed that the suggested analyzing method would be a promising approach for assessing the integrity of concrete structures.
Chan, Lai Gwen; Ho, Mei Jing; Kaur, Palvinder; Singh, Jaspal; Ng, Oon Tek; Lee, Cheng Chuan; Leo, Yee Sin; Carvalhal, Adriana
2016-01-01
In Southeast Asia, subtypes B and CRF01_AE are the prevalent human immunodeficiency virus-1 (HIV-1) subtypes. This study examines the intersubtype differences in clinical indicators and psychiatric symptoms in a multiethnic sample. The study site was a national HIV treatment center. Data were extracted from the Molecular Epidemiology Research study and the HIV-Psychiatry Integrated Mental Health Project, and analyzed according to groups defined by viral subtype. Of 177 subjects, 54.8% were infected with subtype CRF01_AE; 42.9% screened positive on the Hospital Anxiety and Depression Scale (HADS). The CRF01_AE group was significantly older (mean 38.29 years vs. 34.62 years, P=.031) and had advanced immunosuppression (CD4 <200) just prior to HADS screening (33.0% vs. 13.5%, P=.003). By multivariate logistic regression, homosexual transmission [odds ratio (OR) 0.388, 95% confidence interval (CI) 0.158-0.951, P=.038], subtype CRF01_AE (OR 2.898, 95% CI 1.199-7.001, P=.018) and positive HADS screening (OR 2.859, 95% CI 1.261-8.484, P=.012) were associated with advanced immunosuppression; and only advanced immunosuppression was associated with screening positive on the HADS (OR 3.270, 95% CI 1.299-8.227, P=.012). Subtype CRF01_AE is associated with advanced immunosuppression but not with symptoms of anxiety and depression. The results suggest that psychiatric symptoms are associated with advanced HIV disease regardless of subtype. Copyright © 2015 Elsevier Inc. All rights reserved.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-27
... Unemployment Insurance (UI) Wages Are Reported Through PV Powered, Currently Known as AE Solar Energy, Inc... Energy Industries purchased PV Powered, currently known as AE Solar Energy, Inc. in May 2010. Some... separate unemployment insurance (UI) tax account under the name PV Powered, currently known as AE Solar...
Fatigue crack monitoring with coupled piezoelectric film acoustic emission sensors
NASA Astrophysics Data System (ADS)
Zhou, Changjiang
Fatigue-induced cracking is a commonly seen problem in civil infrastructures reaching their original design life. A number of high-profile accidents have been reported in the past that involved fatigue damage in structures. Such incidences often happen without prior warnings due to lack of proper crack monitoring technique. In order to detect and monitor the fatigue crack, acoustic emission (AE) technique, has been receiving growing interests recently. AE can provide continuous and real-time monitoring data on damage progression in structures. Piezoelectric film AE sensor measures stress-wave induced strain in ultrasonic frequency range and its feasibility for AE signal monitoring has been demonstrated recently. However, extensive work in AE monitoring system development based on piezoelectric film AE sensor and sensor characterization on full-scale structures with fatigue cracks, have not been done. A lack of theoretical formulations for understanding the AE signals also hinders the use of piezoelectric film AE sensors. Additionally, crack detection and source localization with AE signals is a very important area yet to be explored for this new type of AE sensor. This dissertation presents the results of both analytical and experimental study on the signal characteristics of surface stress-wave induced AE strain signals measured by piezoelectric film AE sensors in near-field and an AE source localization method based on sensor couple theory. Based on moment tensor theory, generalized expression for AE strain signal is formulated. A special case involving the response of piezoelectric film AE sensor to surface load is also studied, which could potentially be used for sensor calibration of this type of sensor. A new concept of sensor couple theory based AE source localization technique is proposed and validated with both simulated and experimental data from fatigue test and field monitoring. Two series of fatigue tests were conducted to perform fatigue crack monitoring on large-scale steel test specimens using piezoelectric film AE sensors. Continuous monitoring of fatigue crack growth in steel structures is demonstrated in these fatigue test specimens. The use of piezoelectric film AE sensor for field monitoring of existing fatigue crack is also demonstrated in a real steel I-girder bridge located in Maryland. The sensor couple theory based AE source localization is validated using a limited number of piezoelectric film AE sensor data from both fatigue test specimens and field monitoring bridge. Through both laboratory fatigue test and field monitoring of steel structures with active fatigue cracks, the signal characteristics of piezoelectric film AE sensor have been studied in real-world environment.
Sykes, Leanne; Bhayat, Ahmed; Bernitz, Herman
2017-01-01
Dental age estimation (AE) tests are routinely done on living and deceased persons. There is anecdotal evidence suggesting an increase in age estimations due to the refugee crisis. Our aim is to determine the reasons and methods for performing dental AE tests in both living and deceased individuals. Global trends in AE over the past 10 years were also investigated. A database of all forensic laboratories was obtained and an electronic questionnaire was sent to all of them. The questionnaire was self-developed and included questions on the reasons for performing AE tests, the preferred methods used in living and deceased individuals, and the people/organizations who requested these AE tests. The number of tests performed annually varied between 0 and 500 and the majority were on asylum seekers, refugees, and for adoption cases. Most units used multiple techniques to determine the age among the living, but seldom used more than three techniques for the deceased. The majority of tests were requested by coroners and the legal fraternity. There has been an increase in the number of dental AEs carried out and this has been mostly due to asylum seekers and refugees. The most common techniques for the living were variations of Demirjian’s technique while country specific techniques were used for the deceased. PMID:28608845
NASA Astrophysics Data System (ADS)
Cattaneo, Alessandro; Park, Gyuhae; Farrar, Charles; Mascareñas, David
2012-04-01
The acoustic emission (AE) phenomena generated by a rapid release in the internal stress of a material represent a promising technique for structural health monitoring (SHM) applications. AE events typically result in a discrete number of short-time, transient signals. The challenge associated with capturing these events using classical techniques is that very high sampling rates must be used over extended periods of time. The result is that a very large amount of data is collected to capture a phenomenon that rarely occurs. Furthermore, the high energy consumption associated with the required high sampling rates makes the implementation of high-endurance, low-power, embedded AE sensor nodes difficult to achieve. The relatively rare occurrence of AE events over long time scales implies that these measurements are inherently sparse in the spike domain. The sparse nature of AE measurements makes them an attractive candidate for the application of compressed sampling techniques. Collecting compressed measurements of sparse AE signals will relax the requirements on the sampling rate and memory demands. The focus of this work is to investigate the suitability of compressed sensing techniques for AE-based SHM. The work explores estimating AE signal statistics in the compressed domain for low-power classification applications. In the event compressed classification finds an event of interest, ι1 norm minimization will be used to reconstruct the measurement for further analysis. The impact of structured noise on compressive measurements is specifically addressed. The suitability of a particular algorithm, called Justice Pursuit, to increase robustness to a small amount of arbitrary measurement corruption is investigated.
Medvedev, Nickolay S; Shaverina, Anastasiya V; Tsygankova, Alphiya R; Saprykin, Anatoly I
2016-08-01
The paper presents a combined technique of germanium dioxide analysis by inductively coupled plasma atomic emission spectrometry (ICP-AES) with preconcentration of trace elements by distilling off matrix and electrothermal (ETV) introduction of the trace elements concentrate into the ICP. Evaluation of metrological characteristics of the developed technique of high-purity germanium dioxide analysis was performed. The limits of detection (LODs) for 25 trace elements ranged from 0.05 to 20ng/g. The accuracy of proposed technique is confirmed by "added-found" («or spiking») experiment and comparing the results of ETV-ICP-AES and ICP-AES analysis of high purity germanium dioxide samples. Copyright © 2016 Elsevier B.V. All rights reserved.
Cascade Distillation System Development
NASA Technical Reports Server (NTRS)
Callahan, Michael R.; Sargushingh, Miriam; Shull, Sarah
2014-01-01
NASA's Advanced Exploration Systems (AES) Life Support System (LSS) Project is chartered with de-veloping advanced life support systems that will ena-ble NASA human exploration beyond low Earth orbit (LEO). The goal of AES is to increase the affordabil-ity of long-duration life support missions, and to re-duce the risk associated with integrating and infusing new enabling technologies required to ensure mission success. Because of the robust nature of distillation systems, the AES LSS Project is pursuing develop-ment of the Cascade Distillation Subsystem (CDS) as part of its technology portfolio. Currently, the system is being developed into a flight forward Generation 2.0 design.
Auger spectroscopy of fracture surfaces of ceramics
NASA Technical Reports Server (NTRS)
Marcus, H. L.; Harris, J. M.; Szalkowski, F. J.
1974-01-01
Results of Auger electron spectroscopy (AES) studies of fracture surfaces in a series of ceramic materials, including Al2O3, MgO, and Si3N4, which were formed using different processing techniques. AES on the fractured surface of a lunar sample is also discussed. Scanning electron micrograph fractography is used to relate the surface chemistry to the failure mode. Combined argon ion sputtering and AES studies demonstrate the local variations in chemistry near the fracture surface. The problems associated with doing AES in insulators are also discussed, and the experimental techniques directed toward solving them are described.
Schadendorf, Dirk; Wolchok, Jedd D; Hodi, F Stephen; Chiarion-Sileni, Vanna; Gonzalez, Rene; Rutkowski, Piotr; Grob, Jean-Jacques; Cowey, C Lance; Lao, Christopher D; Chesney, Jason; Robert, Caroline; Grossmann, Kenneth; McDermott, David; Walker, Dana; Bhore, Rafia; Larkin, James; Postow, Michael A
2017-12-01
Purpose Approximately 40% of patients with advanced melanoma who received nivolumab combined with ipilimumab in clinical trials discontinued treatment because of adverse events (AEs). We conducted a retrospective analysis to assess the efficacy and safety of nivolumab plus ipilimumab in patients who discontinued treatment because of AEs. Methods Data were pooled from phase II and III trials of patients who received nivolumab 1 mg/kg plus ipilimumab 3 mg/kg, every 3 weeks for four doses, followed by nivolumab monotherapy 3 mg/kg every 2 weeks (N = 409). Efficacy was assessed in all randomly assigned patients who discontinued because of AEs during the induction phase (n = 96) and in those who did not discontinue because of AEs (n = 233). Safety was assessed in treated patients who discontinued because of AEs (n = 176) at any time and in those who did not discontinue because of AEs (n = 231). Results At a minimum follow-up of 18 months, median progression-free survival was 8.4 months for patients who discontinued treatment because of AEs during the induction phase and 10.8 months for patients who did not discontinue because of AEs ( P = .97). Median overall survival had not been reached in either group ( P = .23). The objective response rate was 58.3% for patients who discontinued because of AEs during the induction phase and 50.2% for patients who did not discontinue. The vast majority of grade 3 or 4 AEs occurred during the induction phase, with most resolving after appropriate management. Conclusion Efficacy outcomes seemed similar between patients who discontinued nivolumab plus ipilimumab treatment because of AEs during the induction phase and those who did not discontinue because of AEs. Therefore, even after discontinuation, many patients may continue to derive benefit from combination therapy.
Schadendorf, Dirk; Wolchok, Jedd D.; Hodi, F. Stephen; Chiarion-Sileni, Vanna; Gonzalez, Rene; Rutkowski, Piotr; Grob, Jean-Jacques; Cowey, C. Lance; Lao, Christopher D.; Chesney, Jason; Robert, Caroline; Grossmann, Kenneth; McDermott, David; Walker, Dana; Bhore, Rafia; Larkin, James
2017-01-01
Purpose Approximately 40% of patients with advanced melanoma who received nivolumab combined with ipilimumab in clinical trials discontinued treatment because of adverse events (AEs). We conducted a retrospective analysis to assess the efficacy and safety of nivolumab plus ipilimumab in patients who discontinued treatment because of AEs. Methods Data were pooled from phase II and III trials of patients who received nivolumab 1 mg/kg plus ipilimumab 3 mg/kg, every 3 weeks for four doses, followed by nivolumab monotherapy 3 mg/kg every 2 weeks (N = 409). Efficacy was assessed in all randomly assigned patients who discontinued because of AEs during the induction phase (n = 96) and in those who did not discontinue because of AEs (n = 233). Safety was assessed in treated patients who discontinued because of AEs (n = 176) at any time and in those who did not discontinue because of AEs (n = 231). Results At a minimum follow-up of 18 months, median progression-free survival was 8.4 months for patients who discontinued treatment because of AEs during the induction phase and 10.8 months for patients who did not discontinue because of AEs (P = .97). Median overall survival had not been reached in either group (P = .23). The objective response rate was 58.3% for patients who discontinued because of AEs during the induction phase and 50.2% for patients who did not discontinue. The vast majority of grade 3 or 4 AEs occurred during the induction phase, with most resolving after appropriate management. Conclusion Efficacy outcomes seemed similar between patients who discontinued nivolumab plus ipilimumab treatment because of AEs during the induction phase and those who did not discontinue because of AEs. Therefore, even after discontinuation, many patients may continue to derive benefit from combination therapy. PMID:28841387
1976-07-01
experimental operations, one assesses the realibility of his data in terms of its repeatability. In fact, during the present experiments an effort was... Data Handler Documentation, lIT Research Institute, September 1974 9. Brindley, A.E., et al, Analysis , Test and Evaluation Support to the USAF Advanced...surface above the building foundation level. A.6.3 SURVEYING TECHNIQUE. ACCUKACY, FUTURE USLU An accuracy analysis was not run on the survey data , but
Acoustic emission non-destructive testing of structures using source location techniques.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beattie, Alan G.
2013-09-01
The technology of acoustic emission (AE) testing has been advanced and used at Sandia for the past 40 years. AE has been used on structures including pressure vessels, fire bottles, wind turbines, gas wells, nuclear weapons, and solar collectors. This monograph begins with background topics in acoustics and instrumentation and then focuses on current acoustic emission technology. It covers the overall design and system setups for a test, with a wind turbine blade as the object. Test analysis is discussed with an emphasis on source location. Three test examples are presented, two on experimental wind turbine blades and one onmore » aircraft fire extinguisher bottles. Finally, the code for a FORTRAN source location program is given as an example of a working analysis program. Throughout the document, the stress is on actual testing of real structures, not on laboratory experiments.« less
Analytical Chemistry of Surfaces: Part II. Electron Spectroscopy.
ERIC Educational Resources Information Center
Hercules, David M.; Hercules, Shirley H.
1984-01-01
Discusses two surface techniques: X-ray photoelectron spectroscopy (ESCA) and Auger electron spectroscopy (AES). Focuses on fundamental aspects of each technique, important features of instrumentation, and some examples of how ESCA and AES have been applied to analytical surface problems. (JN)
Non-surgical and non-chemical attempts to treat echinococcosis: do they work?
Tamarozzi, Francesca; Vuitton, Lucine; Brunetti, Enrico; Vuitton, Dominique Angèle; Koch, Stéphane
2014-01-01
Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are chronic, complex and neglected diseases. Their treatment depends on a number of factors related to the lesion, setting and patient. We performed a literature review of curative or palliative non-surgical, non-chemical interventions in CE and AE. In CE, some of these techniques, like radiofrequency thermal ablation (RFA), were shelved after initial attempts, while others, such as High-Intensity Focused Ultrasound, appear promising but are still in a pre-clinical phase. In AE, RFA has never been tested, however, radiotherapy or heavy-ion therapies have been attempted in experimental models. Still, application to humans is questionable. In CE, although prospective clinical studies are still lacking, therapeutic, non-surgical drainage techniques, such as PAIR (puncture, aspiration, injection, re-aspiration) and its derivatives, are now considered a useful option in selected cases. Finally, palliative, non-surgical drainage techniques such as US- or CT-guided percutaneous biliary drainage, centro-parasitic abscesses drainage, or vascular stenting were performed successfully. Recently, endoscopic retrograde cholangiopancreatography (ERCP)-associated techniques have become increasingly used to manage biliary fistulas in CE and biliary obstructions in AE. Development of pre-clinical animal models would allow testing for AE techniques developed for other indications, e.g. cancer. Prospective trials are required to determine the best use of PAIR, and associated procedures, and the indications and techniques of palliative drainage. PMID:25531730
Power Consumption and Calculation Requirement Analysis of AES for WSN IoT.
Hung, Chung-Wen; Hsu, Wen-Ting
2018-05-23
Because of the ubiquity of Internet of Things (IoT) devices, the power consumption and security of IoT systems have become very important issues. Advanced Encryption Standard (AES) is a block cipher algorithm is commonly used in IoT devices. In this paper, the power consumption and cryptographic calculation requirement for different payload lengths and AES encryption types are analyzed. These types include software-based AES-CB, hardware-based AES-ECB (Electronic Codebook Mode), and hardware-based AES-CCM (Counter with CBC-MAC Mode). The calculation requirement and power consumption for these AES encryption types are measured on the Texas Instruments LAUNCHXL-CC1310 platform. The experimental results show that the hardware-based AES performs better than the software-based AES in terms of power consumption and calculation cycle requirements. In addition, in terms of AES mode selection, the AES-CCM-MIC64 mode may be a better choice if the IoT device is considering security, encryption calculation requirement, and low power consumption at the same time. However, if the IoT device is pursuing lower power and the payload length is generally less than 16 bytes, then AES-ECB could be considered.
Acoustic emission and acousto-ultrasonic techniques for wood and wood-based composites: a review
Sumire Kawamoto; R. Sam Williams
2002-01-01
This review focuses on the feasibility of acoustic emission (AE) and acousto-ultrasonic (AU) techniques for monitoring defects in wood, particularly during drying. The advantages and disadvantages of AE and AU techniques are described. Particular emphasis is placed on the propagation and attenuation of ultrasonic waves in wood and the associated measurement problems....
Analysis of Acoustic Emission Parameters from Corrosion of AST Bottom Plate in Field Testing
NASA Astrophysics Data System (ADS)
Jomdecha, C.; Jirarungsatian, C.; Suwansin, W.
Field testing of aboveground storage tank (AST) to monitor corrosion of the bottom plate is presented in this chapter. AE testing data of the ten AST with different sizes, materials, and products were employed to monitor the bottom plate condition. AE sensors of 30 and 150 kHz were used to monitor the corrosion activity of up to 24 channels including guard sensors. Acoustic emission (AE) parameters were analyzed to explore the AE parameter patterns of occurring corrosion compared to the laboratory results. Amplitude, count, duration, and energy were main parameters of analysis. Pattern recognition technique with statistical was implemented to eliminate the electrical and environmental noises. The results showed the specific AE patterns of corrosion activities related to the empirical results. In addition, plane algorithm was utilized to locate the significant AE events from corrosion. Both results of parameter patterns and AE event locations can be used to interpret and locate the corrosion activities. Finally, basic statistical grading technique was used to evaluate the bottom plate condition of the AST.
NASA Technical Reports Server (NTRS)
Appleby, Matthew; Zhu, Dongming; Morscher, Gregory
2015-01-01
Damage evolution of electron beam-physical vapor deposited (EBVD-PVD) ZrO2-7 wt.% Y2O3 thermal barrier coatings (TBCs) under thermal cyclic conditions was monitored using an acoustic emission (AE) technique. The coatings were heated using a laser heat flux technique that yields a high reproducibility in thermal loading. Along with AE, real-time thermal conductivity measurements were also taken using infrared thermography. Tests were performed on samples with induced stress concentrations, as well as calcium-magnesium-alumino-silicate (CMAS) exposure, for comparison of damage mechanisms and AE response to the baseline (as-produced) coating. Analysis of acoustic waveforms was used to investigate damage development by comparing when events occurred, AE event frequency, energy content and location. The test results have shown that AE accumulation correlates well with thermal conductivity changes and that AE waveform analysis could be a valuable tool for monitoring coating degradation and provide insight on specific damage mechanisms.
Genovese, Elizabeth A; Chaer, Rabih A; Taha, Ashraf G; Marone, Luke K; Avgerinos, Efthymios; Makaroun, Michel S; Baril, Donald T
2016-01-01
Acute limb ischemia (ALI) is a highly morbid and fatal vascular emergency with little known about contemporary, long-term patient outcomes. The goal was to determine predictors of long-term mortality and amputation after open and endovascular treatment of ALI. A retrospective review of ALI patients at a single institution from 2005 to 2011 was performed to determine the impact of revascularization technique on 5-year mortality and amputation. For each main outcome 2 multivariable models were developed; the first adjusted for preoperative clinical presentation and procedure type, the second also adjusted for postoperative adverse events (AEs). A total of 445 limbs in 411 patients were treated for ALI. Interventions included surgical thrombectomy (48%), emergent bypass (18%), and endovascular revascularization (34%). Mean age was 68 ± 15 years, 54% were male, and 23% had cancer. Most patients presented with Rutherford classification IIa (54%) or IIb (39%). The etiology of ALI included embolism (27%), in situ thrombosis (28%), thrombosed bypass grafts (32%), and thrombosed stents (13%). Patients treated with open procedures had significantly more advanced ischemia and higher rates of postoperative respiratory failure, whereas patients undergoing endovascular interventions had higher rates of technical failure. Rates of postprocedural bleeding and cardiac events were similar between both treatments. Excluding Rutherford class III patients (n = 12), overall 5-year mortality was 54% (stratified by treatment, 65% for thrombectomy, 63% for bypass, and 36% for endovascular, P < 0.001); 5-year amputation was 28% (stratified by treatment, 18% for thrombectomy, 27% for bypass, and 17% for endovascular, P = 0.042). Adjusting for comorbidities, patient presentation, AEs, and treatment method, the risk of mortality increased with age (hazard ratio [HR] = 1.04, P < 0.001), female gender (HR = 1.50, P = 0.031), cancer (HR = 2.19, P < 0.001), fasciotomy (HR = 1.69, P = 0.204) in situ thrombosis or embolic etiology (HR = 1.73, P = 0.007), cardiac AEs (HR = 2.25, P < 0.001), respiratory failure (HR = 2.72, P < 0.001), renal failure (HR = 4.70, P < 0.001), and hemorrhagic events (HR = 2.25, P = 0.003). Risk of amputation increased with advanced ischemia (Rutherford IIb compared with IIa, HR = 2.57, P < 0.001), thrombosed bypass etiology (HR = 3.53, P = 0.002), open revascularization (OR; HR = 1.95, P = 0.022), and technical failure of primary intervention (HR = 6.01, P < 0.001). After the treatment of ALI, long-term mortality and amputation rates were greater in patients treated with open techniques; OR patients presented with a higher number of comorbidities and advanced ischemia, while also experiencing a higher rate of major postoperative complications. Overall, mortality rates remained high and were most strongly associated with baseline comorbidities, acuity of presentation, and perioperative AEs, particularly respiratory failure. Comparatively, amputation risk was most highly associated with advanced ischemia, thrombosed bypass, and failure of the initial revascularization procedure. Copyright © 2016 Elsevier Inc. All rights reserved.
Non-destructive evaluation of laboratory scale hydraulic fracturing using acoustic emission
NASA Astrophysics Data System (ADS)
Hampton, Jesse Clay
The primary objective of this research is to develop techniques to characterize hydraulic fractures and fracturing processes using acoustic emission monitoring based on laboratory scale hydraulic fracturing experiments. Individual microcrack AE source characterization is performed to understand the failure mechanisms associated with small failures along pre-existing discontinuities and grain boundaries. Individual microcrack analysis methods include moment tensor inversion techniques to elucidate the mode of failure, crack slip and crack normal direction vectors, and relative volumetric deformation of an individual microcrack. Differentiation between individual microcrack analysis and AE cloud based techniques is studied in efforts to refine discrete fracture network (DFN) creation and regional damage quantification of densely fractured media. Regional damage estimations from combinations of individual microcrack analyses and AE cloud density plotting are used to investigate the usefulness of weighting cloud based AE analysis techniques with microcrack source data. Two granite types were used in several sample configurations including multi-block systems. Laboratory hydraulic fracturing was performed with sample sizes ranging from 15 x 15 x 25 cm3 to 30 x 30 x 25 cm 3 in both unconfined and true-triaxially confined stress states using different types of materials. Hydraulic fracture testing in rock block systems containing a large natural fracture was investigated in terms of AE response throughout fracture interactions. Investigations of differing scale analyses showed the usefulness of individual microcrack characterization as well as DFN and cloud based techniques. Individual microcrack characterization weighting cloud based techniques correlated well with post-test damage evaluations.
Marchevsky, M.; Ambrosio, G.; Lamm, M.; ...
2016-02-12
Acoustic emission (AE) detection is a noninvasive technique allowing the localization of the mechanical events and quenches in superconducting magnets. Application of the AE technique is especially advantageous in situations where magnet integrity can be jeopardized by the use of voltage taps or inductive pickup coils. As the prototype module of the transport solenoid (TS) for the Mu2e experiment at Fermilab represents such a special case, we have developed a dedicated six-channel AE detection system and accompanying software aimed at localizing mechanical events during the coil cold testing. The AE sensors based on transversely polarized piezoceramic washers combined with cryogenicmore » preamplifiers were mounted at the outer surface of the solenoid aluminum shell, with a 60° angular step around the circumference. Acoustic signals were simultaneously acquired at a rate of 500 kS/s, prefiltered and sorted based on their arrival time. Next, based on the arrival timing, angular and axial coordinates of the AE sources within the magnet structure were calculated. Furthermore, we present AE measurement results obtained during cooldown, spot heater firing, and spontaneous quenching of the Mu2e TS module prototype and discuss their relevance for mechanical stability assessment and quench localization.« less
Burger, Robert A.; Brady, Mark F.; Bookman, Michael A.; Monk, Bradley J.; Walker, Joan L.; Homesley, Howard D.; Fowler, Jeffrey; Greer, Benjamin E.; Boente, Matthew; Fleming, Gini F.; Lim, Peter C.; Rubin, Stephen C.; Katsumata, Noriyuki; Liang, Sharon X.
2014-01-01
Purpose To evaluate risk factors for GI adverse events (AEs) within a phase III trial of bevacizumab in first-line ovarian cancer therapy. Patients and Methods Women with previously untreated advanced disease after surgery were randomly allocated to six cycles of platinum-taxane chemotherapy plus placebo cycles (C)2 to C22 (R1); chemotherapy plus bevacizumab C2 to C6 plus placebo C7 to C22 (R2); or chemotherapy plus bevacizumab C2 to C22 (R3). Patients were evaluated for history or on-study development of potential risk factors for GI AEs defined as grade ≥ 2 perforation, fistula, necrosis, or hemorrhage. Results Of 1,873 patients enrolled, 1,759 (94%) were evaluable, and 2.8% (50 of 1,759) experienced a GI AE: 10 of 587 (1.7%, R1), 20 of 587 (3.4%, R2), and 20 of 585 (3.4%, R3). Univariable analyses indicated that previous treatment of inflammatory bowel disease (IBD; P = .005) and small bowel resection (SBR; P = .032) or large bowel resection (LBR; P = .012) at primary surgery were significantly associated with a GI AE. The multivariable estimated relative odds of a GI AE were 13.4 (95% CI, 3.44 to 52.3; P < .001) for IBD; 2.05 (95% CI, 1.09 to 3.88; P = .026) for LBR; 1.95 (95% CI, 0.894 to 4.25; P = .093) for SBR; and 2.15 for bevacizumab exposure (aggregated 95% CI, 1.05 to 4.40; P = .036). Conclusion History of treatment for IBD, and bowel resection at primary surgery, increase the odds of GI AEs in patients receiving first-line platinum-taxane chemotherapy for advanced ovarian cancer. After accounting for these risk factors, concurrent bevacizumab doubles the odds of a GI AE, but is not appreciably increased by continuation beyond chemotherapy. PMID:24637999
AT on Buried LPG Tanks Over 13 m3: An Innovative and Practical Solution
NASA Astrophysics Data System (ADS)
Di Fratta, Crescenzo; Ferraro, Antonio; Tscheliesnig, Peter; Lackner, Gerald; Correggia, Vincenzo; Altamura, Nicola
In Italy, since 2005, techniques based on Acoustic Emission have been introduced for testing of underground LPG tanks up to 13 m3, according to the European standard EN 12818:2004. The testing procedure for these tanks plans to install one or more pairs of sensors inside the "dome" suited for the access to the valves and fittings of the tank, directly on the accessible metal shell. This methodology is not applicable for the underground LPG buried tanks, where it is necessary to install a larger number of AE sensors, in order to cover at 100% the whole tank shell, even at very deep positions. Already in 2004, the European standard EN 12820 (Appendix C - Informative)give the possibility to use Acoustic Emission testing of LPG underground or buried tanks with a capacity exceeding 13 m3, but no technique was specified for the application. In 2008, TÜV AUSTRIA ITALIA - BLU SOLUTIONS srl - Italian company of TÜV AUSTRIA Group - has developed a technique to get access at tank shell, where tank capacity is greater than 13 m3 and its' diameter greater than 3,5 m. This methodology was fully in comply with the provisions of the European Standard EN 12819:2010, becoming an innovative solution widely appreciated and is used in Italy since this time. Currently, large companies and petrochemical plants, at the occurrence of the tank's requalification, have engaged TÜV AUSTRIA ITALIA - BLU SOLUTIONS to install such permanent predispositions, which allow access to the tank shell - test object - with diameters from 4 to 8 m. Through this access, you can install the AE sensors needed to cover at 100% the tank surface and then to perform AE test. In an economic crisis period, this technique is proving a valid and practically applicable answer, in order to reduce inspection costs and downtime by offering a technically advanced solution (AT), increasing the safety of the involved operators, protecting natural resources and the environment.
Le Saux, Olivia; Taylor, Aliki; Chia, Victoria; Pillas, Demetris; Kaur, Moninder; Freyer, Gilles
2015-01-01
The purpose of this study was to evaluate the prevalence of comorbidities and adverse events (AEs), and determine the treatment patterns according to platinum-sensitivity status in patients with advanced (stage IIIB-IV) or recurrent epithelial ovarian cancer (EOC). A cross-sectional study was carried out in France with patients over 18 years, diagnosed with advanced (stage IIIB-IV) or recurrent EOC between 2009 and 2012. A total of 23 physicians (oncologists and gynecologists) participated, contributing 127 patients. Data were abstracted by participating physicians into a case report form. Of the 127 patients included, 92 (72.4%) had advanced EOC and 35 (27.6%) had recurrent EOC. A total of 73 comorbidities were reported in 44 patients (34.6%). Vascular (10.2%), metabolic (7.1%), respiratory (5.5%), and psychiatric disorders (5.5%) were the most common types of comorbidities reported. Prevalence of AEs was 74.8%, of which 12.6% were classified as serious. The most common AEs were anemia (16.5%), hematologic events (12.6%), taste change (11.8%), and headache (7.1%). Throughout the follow-up period, twelve patient deaths were reported (six due to disease progression). Of 35 patients with recurrent disease, 16 were highly platinum sensitive (recurrence >12 months after stopping platinum-based therapy), eleven were partially platinum sensitive (recurrence 6-12 months after stopping platinum-based therapy), seven were platinum resistant (recurrence within 6 months of stopping platinum-based therapy or progression while receiving second- or later-line platinum-based therapy), and one was platinum refractory (recurrence within 6 months from the start of first-line platinum-based therapy). In this cross-sectional study of advanced and metastatic ovarian cancer patients, approximately one-third of patients were diagnosed with comorbidities, and approximately three-quarters were diagnosed with AEs (12.6% with severe AEs).
NASA Astrophysics Data System (ADS)
Liu, Chang; Wu, Xing; Mao, Jianlin; Liu, Xiaoqin
2017-07-01
In the signal processing domain, there has been growing interest in using acoustic emission (AE) signals for the fault diagnosis and condition assessment instead of vibration signals, which has been advocated as an effective technique for identifying fracture, crack or damage. The AE signal has high frequencies up to several MHz which can avoid some signals interference, such as the parts of bearing (i.e. rolling elements, ring and so on) and other rotating parts of machine. However, acoustic emission signal necessitates advanced signal sampling capabilities and requests ability to deal with large amounts of sampling data. In this paper, compressive sensing (CS) is introduced as a processing framework, and then a compressive features extraction method is proposed. We use it for extracting the compressive features from compressively-sensed data directly, and also prove the energy preservation properties. First, we study the AE signals under the CS framework. The sparsity of AE signal of the rolling bearing is checked. The observation and reconstruction of signal is also studied. Second, we present a method of extraction AE compressive feature (AECF) from compressively-sensed data directly. We demonstrate the energy preservation properties and the processing of the extracted AECF feature. We assess the running state of the bearing using the AECF trend. The AECF trend of the running state of rolling bearings is consistent with the trend of traditional features. Thus, the method is an effective way to evaluate the running trend of rolling bearings. The results of the experiments have verified that the signal processing and the condition assessment based on AECF is simpler, the amount of data required is smaller, and the amount of computation is greatly reduced.
du Plessis, Marna; du Toit-Prinsloo, Lorraine
2017-04-01
Air embolism (AE) is considered a rare event and can be either iatrogenic or traumatic. Various post-mortem methods to detect AE exist, of which radiology is preferred. The presence of air in the heart can be demonstrated using special dissection techniques where the heart is opened under water or by needle puncture from a water-filled syringe. Three cases of blunt-force head injury are presented herein, with AE being diagnosed by conventional radiography using a Lodox Statscan® full-body digital X-ray machine in all cases. This case series demonstrates that AE due to blunt-force trauma to the head and sinuses might be under-recognised in the forensic post-mortem setting. It also highlights the importance of radiology in diagnosing AE post-mortem, especially where the results of post-mortem techniques might be unsatisfactory.
Application of Advanced Nondestructive Evaluation Techniques for Cylindrical Composite Test Samples
NASA Technical Reports Server (NTRS)
Martin, Richard E.; Roth, Donald J.; Salem, Jonathan A.
2013-01-01
Two nondestructive methods were applied to composite cylinder samples pressurized to failure in order to determine manufacturing quality and monitor damage progression under load. A unique computed tomography (CT) image processing methodology developed at NASA Glenn Research was used to assess the condition of the as-received samples while acoustic emission (AE) monitoring was used to identify both the extent and location of damage within the samples up to failure. Results show the effectiveness of both of these methods in identifying potentially critical fabrication issues and their resulting impact on performance.
Advances in Techniques and Technologies for Air Vehicle Navigation and Guidance
1989-12-01
sur l’automatisation nous amene a poser le probleme de linterface homme /machine non pas comme un sous-prob leme A trai ter en corol lai reA a automat i...conditions de la recherche (couverture nuageuse, temps de recalage allou6,... Zon. do ,rech.h (16ftIU) A~e (32-32) fig. 3 Fo’- L Illustration do Ia...itendue h une logique A valeurs continues sur [- l ,+Il. Ces valeurs de decision sont ensuite pondiries par 1’efficacild relative des critIres pour
1983-05-01
SALPE Technical Conference Series, Volume 4. Society for the Advancement of Material and Process Engineering, Azusa, California. 1972. conference held...dispersion of the stress waves, and scattering from "obstacles" encountered in the line of travel of the wave. Geometric spreading is the loss in signal...amplitude due to the fact that, as the wave travels away from the point AE source in a two- I or three-dimensional medium, the total area of material
Analysing Blast and Fragment Penetration Effects on Composite Helicopter Structures
2005-03-01
7.3 BC/AC 10 -45 7.2/7.3 DE/AE - 4.9/5.0 E/AE - 11 45 8.5/8.6 DE/AE 7.4/7. A’,E’ 4.8/8.5 E/AE 7.4/7.7 A’/E’ = very 9 local12 7.2/7.3 DE/AE - 7.2/7.5 D...6 ±45 7 ±45 8 0/90 9 45 10 0/90 11 ±45 12 0/90 Table 11 : Laminate lay-up for the tensile and in-plane shear test specimen O)2004 Advanced...onderling gevolgen voor de manier van construeren, vergeleken. maar ook voor de kwetsbaarbeid. Schet fins/a~g Deze ontwvikkelingen vereisen aanpassing
Nondestructive evaluation of plasma-sprayed thermal barrier coatings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Andrews, D.J.; Taylor, J.A.T.
Acoustic emission has been used as a nondestructive evaluation technique to examine the thermal shock response of thermal barrier coatings. In this study, samples of partially stabilized zirconia powder were sprayed and acoustic emission (AE) data were taken in a series of thermal shock tests in an effort to correlate AE with a given failure mechanism. Microstructural evidence was examined using parallel beam x-ray diffraction and optical microscopy. The AE data are discussed in terms of cumulative amplitude distributions and the use of this technique to characterize fracture events.
Electromagnetically induced acoustic emission—novel NDT technique for damage evaluation
NASA Astrophysics Data System (ADS)
Finkel, P.; Godinez, V.; Miller, R.; Finlayson, R.
2001-04-01
A recently developed electromagnetically induced acoustic emission technique (EM AE) which can be used for damage assessment of thin walled conducting structures is described. This technique allows a structure to be loaded locally by applying an electromagnetic field in order to produce an AE response, which may be captured by conventional or fiber optic (FO) AE sensors. The advantage of this technique is that the localized dynamic stresses induced by a short current pulse in the presence of an external magnetic field aid in the detection of cracks. Also, it is shown that electromagnetic stimulation can be applied to enhance conventional ultrasonics by modulation of the scattered signal from the defect (EM UT). Experimental data is presented for the case of a fatigue crack near rivet holes in thin walled aluminum structures.
Integrated design and manufacturing for the high speed civil transport
NASA Technical Reports Server (NTRS)
1993-01-01
In June 1992, Georgia Tech's School of Aerospace Engineering was awarded a NASA University Space Research Association (USRA) Advanced Design Program (ADP) to address 'Integrated Design and Manufacturing for the High Speed Civil Transport (HSCT)' in its graduate aerospace systems design courses. This report summarizes the results of the five courses incorporated into the Georgia Tech's USRA ADP program. It covers AE8113: Introduction to Concurrent Engineering, AE4360: Introduction to CAE/CAD, AE4353: Design for Life Cycle Cost, AE6351: Aerospace Systems Design One, and AE6352: Aerospace Systems Design Two. AE8113: Introduction to Concurrent Engineering was an introductory course addressing the basic principles of concurrent engineering (CE) or integrated product development (IPD). The design of a total system was not the objective of this course. The goal was to understand and define the 'up-front' customer requirements, their decomposition, and determine the value objectives for a complex product, such as the high speed civil transport (HSCT). A generic CE methodology developed at Georgia Tech was used for this purpose. AE4353: Design for Life Cycle Cost addressed the basic economic issues for an HSCT using a robust design technique, Taguchi's parameter design optimization method (PDOM). An HSCT economic sensitivity assessment was conducted using a Taguchi PDOM approach to address the robustness of the basic HSCT design. AE4360: Introduction to CAE/CAD permitted students to develop and utilize CAE/CAD/CAM knowledge and skills using CATIA and CADAM as the basic geometric tools. AE6351: Aerospace Systems Design One focused on the conceptual design refinement of a baseline HSCT configuration as defined by Boeing, Douglas, and NASA in their system studies. It required the use of NASA's synthesis codes FLOPS and ACSYNT. A criterion called the productivity index (P.I.) was used to evaluate disciplinary sensitivities and provide refinements of the baseline HSCT configuration. AE6352: Aerospace Systems Design Two was a continuation of Aerospace Systems Design One in which wing concepts were researched and analyzed in more detail. FLOPS and ACSYNT were again used at the system level while other off-the-shelf computer codes were used for more detailed wing disciplinary analysis and optimization. The culmination of all efforts and submission of this report conclude the first year's efforts of Georgia Tech's NASA USRA ADP. It will hopefully provide the foundation for next year's efforts concerning continuous improvement of integrated design and manufacturing for the HSCT.
Evaluation of bridge cables corrosion using acoustic emission technique
NASA Astrophysics Data System (ADS)
Li, Dongsheng; Ou, Jinping
2010-04-01
Owing to the nature of the stress, corrosion of bridge cable may result in catastrophic failure of the structure. However, using electrochemical techniques isn't fully efficient for the detection and control on line of the corrosion phenomenon. A non-destructive testing method based on acoustic emission technique monitoring bridge cable corrosion was explored. The steel strands were placed at room temperature in 5% NaCl solution. Acoustic emission (AE) characteristic parameters were recorded in the whole corrosion experiment process. Based on the plot of cumulated acoustic activity, the bridge cables corrosion included three stages. It can be clearly seen that different stages have different acoustic emission signal characteristics. The AE characteristic parameters would be increased with cables corrosion development. Finally, the bridge cables corrosion experiment with different stress state and different corrosion environment was performed. The results shows that stress magnitude only affects the bridge cable failure time, however, the AE characteristic parameters value has changed a little. It was verified that AE technique can be used to detect the bridge cable early corrosion, investigating corrosion developing trend, and in monitoring and evaluating corrosion damages.
NASA Technical Reports Server (NTRS)
Henkel, Daniel P.
1992-01-01
Physical phenomena associated with the solidification of an aluminum lithium alloy was characterized using acoustic emission (AE) techniques. It is shown that repeatable patterns of AE activity may be correlated to microstructural changes that occur during solidification. The influence of the experimental system on generated signals was examined in the time and frequency domains. The analysis was used to show how an AE signal from solidifying aluminum is changed by each component in the detection system to produce a complex waveform. Conventional AE analysis has shown that a period of high AE activity occurs in pure aluminum, an Al-Cu alloy, and the Al-Li alloy, as the last fraction of solid forms. A model attributes this to the internal stresses of grain boundary formation. An additional period of activity occurs as the last fraction of solid forms, but only in the two alloys. A model attributes this to the formation of interdendritic porosity which was not present in the pure aluminum. The AE waveforms were dominated by resonant effects of the waveguide and the transducer.
Acoustic emission from composite materials. [nondestructive tests
NASA Technical Reports Server (NTRS)
Visconti, I. C.; Teti, R.
1979-01-01
The two basic areas where the acoustic emission (AE) technique can be applied are materials research and the evaluation of structural reliability. This experimental method leads to a better understanding of fracture mechanisms and is an NDT technique particularly well suited for the study of propagating cracks. Experiments are described in which acoustic emissions were unambiguously correlated with microstructural fracture mechanisms. The advantages and limitations of the AE technique are noted.
Slatkin, Neal E; Lynn, Richard; Su, Chinyu; Wang, Wenjin; Israel, Robert J
2011-11-01
Methylnaltrexone is a selective peripherally acting mu-opioid receptor antagonist that decreases the constipating effects of opioids without affecting centrally mediated analgesia. In two double-blind, placebo-controlled, Phase III studies of methylnaltrexone for opioid-induced constipation in patients with advanced illness, abdominal pain was the most common adverse event (AE) reported. This analysis sought to further characterize the Medical Dictionary for Regulatory Activities-defined abdominal pain AEs experienced in these studies. A post hoc analysis of verbatim descriptions was used to further assess AEs characterized as abdominal pain in both trials. Descriptive summary statistics were used to assess severity of abdominal pain, effect of abdominal pain on global pain scores, and other characteristics. Logistic regression analysis was used to determine the association of baseline characteristics with abdominal pain. Most verbatim descriptions of abdominal pain referred to "abdominal cramps" or "cramping." Abdominal pain AEs were mostly mild to moderate in severity and did not affect patients' global evaluation of pain. The incidence of abdominal pain AEs in methylnaltrexone-treated patients was greatest after the first dose and decreased with subsequent doses. No association between abdominal pain AEs and most baseline patient characteristics was noted. Abdominal pain AEs in methylnaltrexone-treated patients in clinical trials are usually described as "cramps" or "cramping," are mostly mild to moderate in severity, and decrease in incidence with subsequent dosing. Copyright © 2011 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Huang, Chun-Yi; Chang, Hsin-Wei; Chang, Che-Chen
2018-03-01
Knowledge about the chemical compositions of meso/nanomaterials is fundamental to development of their applications in advanced technologies. Auger electron spectroscopy (AES) is an effective analysis method for the characterization of meso/nanomaterial structures. Although a few studies have reported the use of AES for the analysis of the local composition of these structures, none have explored in detail the validity of the meso/nanoanalysis results generated by the AES instrument. This paper addresses the limitations of AES and the corrections necessary to offset them for this otherwise powerful meso/nanoanalysis tool. The results of corrections made to the AES multi-point analysis of high-density copper-based meso/nanostructures provides major insights into their local chemical compositions and technological prospects, which the primitive composition output of the AES instrument failed to provide.
DNA barcoding and wing morphometrics to distinguish three Aedes vectors in Thailand.
Sumruayphol, Suchada; Apiwathnasorn, Chamnarn; Ruangsittichai, Jiraporn; Sriwichai, Patchara; Attrapadung, Siriluck; Samung, Yudthana; Dujardin, Jean-Pierre
2016-07-01
Aedes aegypti (Diptera: Culicidae) (L.), Ae. albopictus (Skuse), and Ae. scutellaris (Walker) are important mosquito vectors of dengue and chikungunya viruses. They are morphologically similar and sympatric in some parts of their distribution; therefore, there is a risk of incorrect morphological identification. Any confusion could have a negative impact on epidemiological studies or control strategies. Therefore, we explored two modern tools to supplement current morphological identification: DNA barcoding and geometric morphometric analyses. Field larvae were reared to adults and carefully classified based on morphological traits. The genetic analysis was based on the 658bp each of 30COI sequences. Some Culex spp., Mansonia bonneae, were included as outgroups, and inclusion of a few other Aedes spp. facilitated phylogenetic inference of the relationship between Ae. albopictus and Ae. scutellaris. The two species were separated by an average interspecific divergence of 0.123 (0.119-0.127). Morphometric examination included landmark- (392 specimens) and outline-based (317 specimens) techniques. The shape of the wing showed different discriminating power based on sex and digitizing technique. This is the first time that Ae. scutellaris and Ae. albopictus have been compared using these two techniques. We confirm that these morphologically close species are valid, and that geometric morphometrics can considerably increase the reliability of morphological identification. Copyright © 2016 Elsevier B.V. All rights reserved.
Avionics Architectures for Exploration: Wireless Technologies and Human Spaceflight
NASA Technical Reports Server (NTRS)
Goforth, Montgomery B.; Ratliff, James E.; Barton, Richard J.; Wagner, Raymond S.; Lansdowne, Chatwin
2014-01-01
The authors describe ongoing efforts by the Avionics Architectures for Exploration (AAE) project chartered by NASA's Advanced Exploration Systems (AES) Program to evaluate new avionics architectures and technologies, provide objective comparisons of them, and mature selected technologies for flight and for use by other AES projects. The AAE project team includes members from most NASA centers and from industry. This paper provides an overview of recent AAE efforts, with particular emphasis on the wireless technologies being evaluated under AES to support human spaceflight.
Zhang, Zhen-Xin; Liu, Chun-Feng; Tao, En-Xiang; Shao, Ming; Liu, Yi-Ming; Wang, Jian; Asgharnejad, Mahnaz; Xue, Hai-Bo; Surmann, Erwin; Bauer, Lars
2017-11-01
Rotigotine was demonstrated to be efficacious and well-tolerated in three placebo-controlled studies (CLEOPATRA-PD/PREFER/SP921) of patients with advanced-stage Parkinson's disease (PD), most of whom were Caucasian. This multicenter phase 3 study (SP1037; NCT01646255) was the first to investigate the efficacy and safety of rotigotine in Chinese patients with advanced-stage PD. Chinese patients with PD, inadequately controlled on levodopa (stable dose ≥200 mg/day), with ≥2.5 h/day "off" time, and Hoehn & Yahr stage 2-4, were randomized 1:1 to receive transdermal rotigotine or placebo, titrated over ≤7 weeks, maintained at optimal/maximum dose (4-16 mg/24 h) for 12 weeks. Primary efficacy variable: mean change in absolute "off" time (according to patient diaries) from baseline to end of maintenance. Safety variables included adverse events (AEs) and discontinuations due to AEs. 346 patients were randomized and 89.9% completed the study (87.8% placebo; 92.0% rotigotine). All were Chinese (58.7% male; mean ± SD age: 62.2 ± 8.9 years; mean ± SD time since PD diagnosis: 6.62 ± 3.70 years). Rotigotine significantly reduced "off" time vs placebo (LS mean [95% CI] treatment difference: -1.20 h/day [-1.83, -0.57]; p = 0.0002), and resulted in more responders (≥30% decrease in "off" time: 36.9% placebo; 48.8% rotigotine; p = 0.0269). AEs were reported for 86 (50.0%) placebo- and 103 (59.2%) rotigotine-treated patients; 15 discontinued due to AEs (placebo 7; rotigotine 8). The most common AEs (≥5%) were dizziness, nausea, pruritus, and dyskinesia. Rotigotine was efficacious in Chinese patients with advanced-stage PD as add-on therapy to levodopa, significantly reducing "off" time vs placebo; the treatment difference was similar to that observed in previous studies of mainly Caucasian patients. Rotigotine was generally well-tolerated and had a similar AE profile to those observed in previous studies. Copyright © 2017 Elsevier Ltd. All rights reserved.
A novel Bayesian approach to acoustic emission data analysis.
Agletdinov, E; Pomponi, E; Merson, D; Vinogradov, A
2016-12-01
Acoustic emission (AE) technique is a popular tool for materials characterization and non-destructive testing. Originating from the stochastic motion of defects in solids, AE is a random process by nature. The challenging problem arises whenever an attempt is made to identify specific points corresponding to the changes in the trends in the fluctuating AE time series. A general Bayesian framework is proposed for the analysis of AE time series, aiming at automated finding the breakpoints signaling a crossover in the dynamics of underlying AE sources. Copyright © 2016 Elsevier B.V. All rights reserved.
Deformation and failure information from composite materials via acoustic emission
NASA Technical Reports Server (NTRS)
Hamstad, M. A.
1978-01-01
The paper reviews some principles of applying acoustic emission (AE) to the study of fiber-composite materials and structures. This review covers the basics of using AE to monitor the deformation and fracture processes that occur when fiber-composite materials are stressed. Also, new results in some areas of current research interest are presented. The following areas are emphasized: study of couplants for AE testing of composites, evaluation of a special immersion-type AE transducer, and wave propagation complications and the development of techniques for locating AE sources in Kevlar 49/epoxy composite pre
Granato, Christine M; Kaul, Vivek; Kothari, Truptesh; Damania, Dushyant; Kothari, Shivangi
2016-08-01
The advanced endoscopy (AE) fellowship is a popular career track for graduating gastroenterology fellows. The number of fellows completing AE fellowships and the number of programs offering this training have increased in the past 5 years. Despite this, we suspect that the number of AE attending (staff physician) positions have decreased (relative to the number of fellows graduating), raising concerns regarding AE job market saturation. Our aim was to survey practicing gastroenterology physicians who completed an AE fellowship within the past 5 years regarding their current professional status. A 16-question survey was distributed using Research Electronic Data Capture by e-mail to practicing gastroenterologists who completed an AE fellowship between 2009 and 2013. The survey questions elicited information regarding demographics, professional status, and additional information. A total of 96 invitations were distributed via e-mail. Forty-one of 96 respondents (43%) replied to the survey. Approximately half of the respondents were employed in an academic practice, with the remainder in private practice (56% and 44%, respectively). Nearly half (46%) of the respondents found it "difficult" to find an AE position after training. Thirty-nine percent of private-practice endoscopists were performing > 200 ERCPs/year, whereas 65% were doing so in academic settings (P = .09). Fifty-six percent of respondents were in small practices (0 to 1 partner), with a significantly smaller group size in private versus academic practice (72% versus 43%, P = .021). Seventy-eight percent of respondents believed the AE job market was saturated; most responded that the AE job market was saturated in both academic and private practice (44%), whereas 34% believed the job market was saturated in academics only. Most respondents (73%) who were training AE fellows found it difficult to place them in AE attending positions. Respondents from academic practice found it significantly more difficult to balance work and personal life compared with those in private practice (87% versus 33%, respectively; P = .0004). This index survey highlights the trends related to the current state of the post-AE fellowship professional landscape. Further evaluation and discussion are needed to address these evolving issues in professional practice in the field of gastroenterology. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.
USDA-ARS?s Scientific Manuscript database
New tools are clearly needed for integrated mosquito management of Ae. aegypti. We describe the sterile insect technique (SIT) that we are developing as a method to control Ae. aegypti by partnering with two prominent Florida mosquito control districts (MCD) and the FAO/IAEA Insect Pest Control Sub...
Acoustic emission characteristics of copper alloys under low-cycle fatigue conditions
NASA Technical Reports Server (NTRS)
Krampfner, Y.; Kawamoto, A.; Ono, K.; Green, A.
1975-01-01
The acoustic emission (AE) characteristics of pure copper, zirconium-copper, and several copper alloys were determined to develop nondestructive evaluation schemes of thrust chambers through AE techniques. The AE counts rms voltages, frequency spectrum, and amplitude distribution analysis evaluated AE behavior under fatigue loading conditions. The results were interpreted with the evaluation of wave forms, crack propagation characteristics, as well as scanning electron fractographs of fatigue-tested samples. AE signals at the beginning of a fatigue test were produced by a sample of annealed alloys. A sample of zirconium-containing alloys annealed repeatedly after each fatigue loading cycle showed numerous surface cracks during the subsequent fatigue cycle, emitting strong-burst AE signals. Amplitude distribution analysis exhibits responses that are characteristic of certain types of AE signals.
Employment of adaptive learning techniques for the discrimination of acoustic emissions
NASA Astrophysics Data System (ADS)
Erkes, J. W.; McDonald, J. F.; Scarton, H. A.; Tam, K. C.; Kraft, R. P.
1983-11-01
The following aspects of this study on the discrimination of acoustic emissions (AE) were examined: (1) The analytical development and assessment of digital signal processing techniques for AE signal dereverberation, noise reduction, and source characterization; (2) The modeling and verification of some aspects of key selected techniques through a computer-based simulation; and (3) The study of signal propagation physics and their effect on received signal characteristics for relevant physical situations.
Obenauer, P J; Kaufman, P E; Kline, D L; Allan, S A
2010-10-01
A sampling study using a BG-Sentinel trap baited with CO(2), a gravid trap baited with an oak-pine infusion, a human subject, and a vegetative aspirator was conducted to compare their reliability at detecting Aedes albopictus Skuse in suburban and sylvatic habitats. We collected 73,849 mosquitoes, representing 29 species from 11 genera over a 20-wk period. The BG-Sentinel trap accounted for over 85% of all Ae. albopictus captured and was significantly more effective at detecting the presence of Ae. albopictus compared with the other three techniques. Landing counts provided the fewest mosquito species (n = 10), yet provided a quick and effective weekly assessment of the major biting species and were the most effective method for sampling Ae. albopictus within a 10-min period. Fewer Ae. albopictus were sampled from sylvatic habitats compared with suburban ones. Sampling criteria advantageous for surveying Ae. albopictus and other mosquito species are discussed.
Analysis of Dermatologic Events in Vemurafenib-Treated Patients With Melanoma
Duvic, Madeleine; Hauschild, Axel; Prieto, Victor G.; Robert, Caroline; Schadendorf, Dirk; Kim, Caroline C.; McCormack, Christopher J.; Myskowski, Patricia L.; Spleiss, Olivia; Trunzer, Kerstin; Su, Fei; Nelson, Betty; Nolop, Keith B.; Grippo, Joseph F.; Lee, Richard J.; Klimek, Matthew J.; Troy, James L.; Joe, Andrew K.
2013-01-01
Background. Vemurafenib has been approved for the treatment of patients with advanced BRAFV600E-mutant melanoma. This report by the Vemurafenib Dermatology Working Group presents the characteristics of dermatologic adverse events (AEs) that occur in vemurafenib-treated patients, including cutaneous squamous cell carcinoma (cuSCC). Methods. Dermatologic AEs were assessed from three ongoing trials of BRAFV600E mutation-positive advanced melanoma. Histologic central review and genetic characterization were completed for a subset of cuSCC lesions. Results. A total of 520 patients received vemurafenib. The most commonly reported AEs were dermatologic AEs, occurring in 92%–95% of patients. Rash was the most common AE (64%–75% of patients), and the most common types were rash not otherwise specified, erythema, maculopapular rash, and folliculitis. Rash development did not appear to correlate with tumor response. Photosensitivity occurred in 35%–63% of patients, and palmar-plantar erythrodysesthesia (PPE) occurred in 8%–10% of patients. The severity of rash, photosensitivity, and PPE were mainly grade 1 or 2. In all, 19%–26% of patients developed cuSCC, mostly keratoacanthomas (KAs). The majority of patients with cuSCC continued therapy without dose reduction after resection. Genetic analysis of 29 cuSCC/KA samples demonstrated HRAS mutations in 41%. Conclusions. Dermatologic AEs associated with vemurafenib treatment in patients with melanoma were generally manageable with supportive care measures. Dose interruptions and/or reductions were required in <10% of patients. PMID:23457002
Chen, Fei; Jin, Lingjing; Nie, Zhiyu
2017-01-01
We aimed to comprehensively analyse the safety and efficiency of rotigotine for treating Parkinson's disease (PD). We conducted systematic literature searches of Cochrane library, PubMed and Embase databases up to April 2016, with 'Rotigotine', 'Parkinson Disease ' and 'Parkinson's disease' as key searching terms. Outcomes, including Unified Parkinson's Disease Rating Scale (UPDRS) Part III and Part II scores, 'off' time, adverse events (AEs), serious AEs and discontinuation because of AEs, were compared between rotigotine and placebo groups under a fixed or random effect model. For dichotomous and continuous data, risk ratio (RR) and weighted mean difference with their corresponding 95% confidence intervals (95% CIs) were taken as the effect sizes to calculate merged results. Twelve eligible studies were included. For patients with early or advanced PD, rotigotine could significantly improve UPDRS Part III and Part II scores (p < 0.001) and it had significantly higher incidence of AEs than the placebo (p < 0.001). Regarding discontinuation because of AEs, rotigotine showed a significant advantage over placebo in patients with early PD, whereas the overall result demonstrated no statistically significant difference between the groups. Rotigotine can improve daily living and motor ability of patients with PD, although it has higher incidence of AEs. Rotigotine might be more appropriate for patients with advanced PD than for those with early PD. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-05
... are reported through PV Powered, currently known as AE Solar Energy, Inc., Bend Oregon, who became... Workers Whose Unemployment Insurance (UI) Wages Are Reported Through PV Powered, Currently Known as AE Solar Energy, Inc., Bend, Oregon; Amended Certification Regarding Eligibility To Apply for Worker...
Larkin, James; Chmielowski, Bartosz; Lao, Christopher D; Hodi, F Stephen; Sharfman, William; Weber, Jeffrey; Suijkerbuijk, Karijn P M; Azevedo, Sergio; Li, Hewei; Reshef, Daniel; Avila, Alexandre; Reardon, David A
2017-06-01
Despite unprecedented efficacy across multiple tumor types, immune checkpoint inhibitor therapy is associated with a unique and wide spectrum of immune-related adverse events (irAEs), including neurologic events ranging from mild headache to potentially life-threatening encephalitis. Here, we summarize neurologic irAEs associated with nivolumab and ipilimumab melanoma treatment, present cases of treatment-related encephalitis, and provide practical guidance on diagnosis and management. We searched a Global Pharmacovigilance and Epidemiology database for neurologic irAEs reported over an 8-year period in patients with advanced melanoma receiving nivolumab with or without ipilimumab from 12 studies sponsored by Bristol-Myers Squibb. Serious neurologic irAEs were reviewed, and relationship to nivolumab or ipilimumab was assigned. In our search of 3,763 patients, 35 patients (0.93%) presented with 43 serious neurologic irAEs, including neuropathy ( n = 22), noninfective meningitis ( n = 5), encephalitis ( n = 6), neuromuscular disorders ( n = 3), and nonspecific adverse events ( n = 7). Study drug was discontinued ( n = 20), interrupted ( n = 8), or unchanged ( n = 7). Most neurologic irAEs resolved (26/35 patients; 75%). Overall, median time to onset was 45 days (range 1-170) and to resolution was 32 days (2-809+). Median time to onset of encephalitis was 55.5 days (range 18-297); four cases resolved and one was fatal. Both oncologists and neurologists need to be aware of signs and symptoms of serious but uncommon neurologic irAEs associated with checkpoint inhibitors. Prompt diagnosis and management using an established algorithm are critical to minimize serious complications from these neurologic irAEs. With increasing use of checkpoint inhibitors in cancer, practicing oncologists need to be aware of the potential risk of neurologic immune-related adverse events and be able to provide prompt treatment of this uncommon, but potentially serious, class of adverse events. We summarize neurologic adverse events related to nivolumab alone or in combination with ipilimumab in patients with advanced melanoma from 12 studies and examine in depth 6 cases of encephalitis. We also provide input and guidance on the existing neurologic adverse events management algorithm for nivolumab and ipilimumab. © AlphaMed Press 2017.
Chmielowski, Bartosz; Lao, Christopher D.; Hodi, F. Stephen; Sharfman, William; Weber, Jeffrey; Suijkerbuijk, Karijn P. M.; Azevedo, Sergio; Li, Hewei; Reshef, Daniel; Avila, Alexandre; Reardon, David A.
2017-01-01
Abstract Background. Despite unprecedented efficacy across multiple tumor types, immune checkpoint inhibitor therapy is associated with a unique and wide spectrum of immune‐related adverse events (irAEs), including neurologic events ranging from mild headache to potentially life‐threatening encephalitis. Here, we summarize neurologic irAEs associated with nivolumab and ipilimumab melanoma treatment, present cases of treatment‐related encephalitis, and provide practical guidance on diagnosis and management. Methods. We searched a Global Pharmacovigilance and Epidemiology database for neurologic irAEs reported over an 8‐year period in patients with advanced melanoma receiving nivolumab with or without ipilimumab from 12 studies sponsored by Bristol‐Myers Squibb. Serious neurologic irAEs were reviewed, and relationship to nivolumab or ipilimumab was assigned. Results. In our search of 3,763 patients, 35 patients (0.93%) presented with 43 serious neurologic irAEs, including neuropathy (n = 22), noninfective meningitis (n = 5), encephalitis (n = 6), neuromuscular disorders (n = 3), and nonspecific adverse events (n = 7). Study drug was discontinued (n = 20), interrupted (n = 8), or unchanged (n = 7). Most neurologic irAEs resolved (26/35 patients; 75%). Overall, median time to onset was 45 days (range 1–170) and to resolution was 32 days (2–809+). Median time to onset of encephalitis was 55.5 days (range 18–297); four cases resolved and one was fatal. Conclusion. Both oncologists and neurologists need to be aware of signs and symptoms of serious but uncommon neurologic irAEs associated with checkpoint inhibitors. Prompt diagnosis and management using an established algorithm are critical to minimize serious complications from these neurologic irAEs. Implications for Practice. With increasing use of checkpoint inhibitors in cancer, practicing oncologists need to be aware of the potential risk of neurologic immune‐related adverse events and be able to provide prompt treatment of this uncommon, but potentially serious, class of adverse events. We summarize neurologic adverse events related to nivolumab alone or in combination with ipilimumab in patients with advanced melanoma from 12 studies and examine in depth 6 cases of encephalitis. We also provide input and guidance on the existing neurologic adverse events management algorithm for nivolumab and ipilimumab. PMID:28495807
Development of a thick film PZT foil sensor for use in structural health monitoring applications.
Pickwell, Andrew J; Dorey, Robert A; Mba, David
2013-02-01
Acoustic emission (AE) monitoring is a technique of growing interest in the field of nondestructive testing (NDT). The use of AE devices to monitor the health of structural components is currently limited by the cost of AE equipment, which prohibits the permanent placement of AE devices on structures for the purposes of continuous monitoring and the monitoring of areas with limited access. Micro electromechanical systems (MEMS) can provide solutions to these problems. We present the manufacture of a 4.4-μm-thick lead zirconate titanate (PZT) film on a 110-μm-thick titanium foil substrate for use as an AE sensor. The thick-film sensor is benchmarked against commercially available AE sensors in static and dynamic monitoring applications. The thick-film AE device is found to perform well in the detection of AE in static applications. A low signal-to-noise ratio is found to prohibit the detection of AE in a dynamic application.
Non-destructive examination of interfacial debonding using acoustic emission.
Li, Haiyan; Li, Jianying; Yun, Xiaofei; Liu, Xiaozhou; Fok, Alex Siu-Lun
2011-10-01
This study aims to assess the viability of using the acoustic emission (AE) measurement technique to detect and monitor in situ the interfacial debonding in resin composite restorations due to build-up of shrinkage stresses during polymerization of the composite. The non-destructive testing technique that measures acoustic emission (AE) was used to detect and monitor the interfacial debonding in resin composite during curing of the composite. Four groups of specimens, n=4 each, were tested: (1) intact human molars with Class-I cavities restored with the composite Z100 (3M ESPE, USA); (2) intact human molars with Class-I cavities restored with the composite Filtek™ P90 (3M ESPE, USA); (3) ring samples prepared from the root of a single bovine tooth and 'restored' with Z100; (4) freestanding pea-size specimens of Z100 directly placed on the AE sensor. The restorations in Groups (1)-(3) were bonded to the tooth tissues with the adhesive Adper™ Scotchbond™ SE Self-Etch (3M ESPE, USA). The composites in all the specimens were cured with a blue light (3M ESPE, USA) for 40s. The AE signals were recorded continuously for 10 min from the start of curing. Non-destructive 3D imaging was performed using X-ray micro-computed tomography (micro-CT) to examine the bonding condition at the tooth-restoration interface. The development of AE events followed roughly that of the shrinkage stress, which was determined separately by the cantilever beam method. The number of AE events in the real human tooth samples was more than that in the ring samples, and no AE events were detected in the pea-size specimens placed directly on the AE sensor. The number of AE events recorded in the specimens restored using Z100 was more than that found in specimens restored with Filtek P90. The micro-CT imaging results showed clear interfacial debondings in the tooth specimens restored with Z100 after curing, but no clear debonding was found in the P90 specimens. The AE technique is an effective tool for detecting and monitoring in situ the interfacial debonding of composite restorations during curing. It can potentially be employed to evaluate the development of shrinkage stress and the quality of interfacial bonds in teeth restored with different composite materials, cavity geometries, and restorative techniques. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Al-Jumaili, Safaa Kh.; Pearson, Matthew R.; Holford, Karen M.; Eaton, Mark J.; Pullin, Rhys
2016-05-01
An easy to use, fast to apply, cost-effective, and very accurate non-destructive testing (NDT) technique for damage localisation in complex structures is key for the uptake of structural health monitoring systems (SHM). Acoustic emission (AE) is a viable technique that can be used for SHM and one of the most attractive features is the ability to locate AE sources. The time of arrival (TOA) technique is traditionally used to locate AE sources, and relies on the assumption of constant wave speed within the material and uninterrupted propagation path between the source and the sensor. In complex structural geometries and complex materials such as composites, this assumption is no longer valid. Delta T mapping was developed in Cardiff in order to overcome these limitations; this technique uses artificial sources on an area of interest to create training maps. These are used to locate subsequent AE sources. However operator expertise is required to select the best data from the training maps and to choose the correct parameter to locate the sources, which can be a time consuming process. This paper presents a new and improved fully automatic delta T mapping technique where a clustering algorithm is used to automatically identify and select the highly correlated events at each grid point whilst the "Minimum Difference" approach is used to determine the source location. This removes the requirement for operator expertise, saving time and preventing human errors. A thorough assessment is conducted to evaluate the performance and the robustness of the new technique. In the initial test, the results showed excellent reduction in running time as well as improved accuracy of locating AE sources, as a result of the automatic selection of the training data. Furthermore, because the process is performed automatically, this is now a very simple and reliable technique due to the prevention of the potential source of error related to manual manipulation.
NASA Technical Reports Server (NTRS)
Liang, Steven Y.; Dornfeld, David A.; Nickerson, Jackson A.
1987-01-01
The coloring effect on the acoustic emission signal due to the frequency response of the data acquisition/processing instrumentation may bias the interpretation of AE signal characteristics. In this paper, a frequency domain deconvolution technique, which involves the identification of the instrumentation transfer functions and multiplication of the AE signal spectrum by the inverse of these system functions, has been carried out. In this way, the change in AE signal characteristics can be better interpreted as the result of the change in only the states of the process. Punch stretching process was used as an example to demonstrate the application of the technique. Results showed that, through the deconvolution, the frequency characteristics of AE signals generated during the stretching became more distinctive and can be more effectively used as tools for process monitoring.
The effect of CFRP on retrofitting of damaged HSRC beams using AE technique
NASA Astrophysics Data System (ADS)
Soffian Noor, M. S.; Noorsuhada, M. N.
2017-12-01
This paper presents the effect of carbon fibre reinforced polymer (CFRP) on retrofitted high strength reinforced concrete (HSRC) beams using acoustic emission (AE) technique. Two RC beam parameters were prepared. The first was the control beam which was undamaged HSRC beam. The second was the damaged HSRC beam retrofitted with CFRP on the soffit. The main objective of this study is to assess the crack modes of HSRC beams using AE signal strength. The relationship between signal strength, load and time were analysed and discussed. The crack pattern observed from the visual observation was also investigated. HSRC beam retrofitted with CFRP produced high signal strength compared to control beam. It demonstrates the effect of the AE signal strength for interpretation and prediction of failure modes that might occur in the beam specimens.
The Present Status of Using Natural Gas Cylinders and Acoustic Emission in Thailand
NASA Astrophysics Data System (ADS)
Jomdecha, C.; Jirarungsatian, C.; Methong, W.; Poopat, B.
This chapter presents the status of using natural gas cylinders (CNG/NGV) and acoustic emission (AE) in Thailand. During the period from 2006 to 2013, more than 600,000 CNG cylinder units for vehicles were installed and used for transportation, cars, and trucks in Thailand. The number of cylinder units will be tentatively increased in the future due to the increase in gasoline price. Due to the use of high-pressurization equipment in public, the issue of a risk to public safety has been raised. As of this writing, in 2013, the testing standard from the Thai Department of Energy Business recommends inspection every 5 years using effective inspection methods in order to guarantee safe usage of gas cylinders, including the AE method, following ISO 16148. Normally in Thailand, AE is used in research and petrochemical plants as a special technique. The main applications are testing of pressure vessels, aboveground storage tanks, and university research. Few companies are available to conduct AE for testing natural gas cylinders due to the limited safety of the high-pressure operation and AE equipment and a lack of qualified AE personnel. To develop AE techniques, equipment, procedures, and acceptance criteria of natural gas cylinders are the main focus of AE personnel in Thailand. A desired achievement for current development is for natural gas cylinder testing, which can be applied in field tests and supported by a national testing standard.
1979-04-01
edge up. The influence of the aircraft on the static pressure reading from the pitot boom was determined with a scaled version of the pltot probe...stabilization before advancing to the next port. Jet exhaust simulation flow was monitored by internal duct pressure and temperature rakes . Standard...Mach numbers 0.6 and 1.2, Figs. 24 and 25. 13 AE DC-TR-79-10 At supersonic speeds, changes in the afterbody and nozzle axial loads (Fig. 22b) are
Adverse Effects of Electroconvulsive Therapy.
Andrade, Chittaranjan; Arumugham, Shyam Sundar; Thirthalli, Jagadisha
2016-09-01
Electroconvulsive therapy (ECT) is an effective treatment commonly used for depression and other major psychiatric disorders. We discuss potential adverse effects (AEs) associated with ECT and strategies for their prevention and management. Common acute AEs include headache, nausea, myalgia, and confusion; these are self-limiting and are managed symptomatically. Serious but uncommon AEs include cardiovascular, pulmonary, and cerebrovascular events; these may be minimized with screening for risk factors and by physiologic monitoring. Although most cognitive AEs of ECT are short-lasting, troublesome retrograde amnesia may rarely persist. Modifications of and improvements in treatment techniques minimize cognitive and other AEs. Copyright © 2016 Elsevier Inc. All rights reserved.
AES Water Architecture Study Interim Results
NASA Technical Reports Server (NTRS)
Sarguisingh, Miriam J.
2012-01-01
The mission of the Advanced Exploration System (AES) Water Recovery Project (WRP) is to develop advanced water recovery systems in order to enable NASA human exploration missions beyond low earth orbit (LEO). The primary objective of the AES WRP is to develop water recovery technologies critical to near term missions beyond LEO. The secondary objective is to continue to advance mid-readiness level technologies to support future NASA missions. An effort is being undertaken to establish the architecture for the AES Water Recovery System (WRS) that meets both near and long term objectives. The resultant architecture will be used to guide future technical planning, establish a baseline development roadmap for technology infusion, and establish baseline assumptions for integrated ground and on-orbit environmental control and life support systems (ECLSS) definition. This study is being performed in three phases. Phase I of this study established the scope of the study through definition of the mission requirements and constraints, as well as indentifying all possible WRS configurations that meet the mission requirements. Phase II of this study focused on the near term space exploration objectives by establishing an ISS-derived reference schematic for long-duration (>180 day) in-space habitation. Phase III will focus on the long term space exploration objectives, trading the viable WRS configurations identified in Phase I to identify the ideal exploration WRS. The results of Phases I and II are discussed in this paper.
Piezoelectric micromachined acoustic emission sensors for early stage damage detection in structures
NASA Astrophysics Data System (ADS)
Kabir, Minoo; Kazari, Hanie; Ozevin, Didem
2018-03-01
Acoustic emission (AE) is a passive nondestructive evaluation (NDE) method that relies on the energy release of active flaws. The passive nature of this NDE method requires highly sensitive transducers in addition to low power and lightweight characteristics. With the advancement of micro-electro-mechanical systems (MEMS), acoustic emission (AE) transducers can be developed in low power and miniaturized. In this paper, the AE transducers operating in plate flexural mode driven piezoelectrically known as Piezoelectric Micromachined Ultrasonic Transducers (PMUTs) are presented. The AE PMUTs are manufactured using PiezoMUMPS process by MEMSCAP and tuned to 46 kHz and 200 kHz. The PiezoMUMPs is a 5-mask level SOI (silicon-on-insulator) patterning and etching process followed by deposition of 0.5 micron Aluminum Nitride (AlN) to form piezoelectric layer to form the transducers. The AE transducers are numerically modeled using COMSOL Multiphysics software in order to optimize the performance before manufacturing. The electrometrical characterization experiments are presented. The efficiency of the proposed AE PMUTs compared to the conventional AE transducers in terms of power consumption, weight and sensitivity is presented.
Kim, Dong-Wan; Garon, Edward B.; Jatoi, Aminah; Keefe, Dorothy M.; Lacouture, Mario E.; Sonis, Stephen; Gernhardt, Diana; Wang, Tao; Giri, Nagdeep; Doherty, Jim P.; Nadanaciva, Sashi; O’Connell, Joseph; Sbar, Eric; Cho, Byoung Chul
2017-01-01
Objectives Dacomitinib is a pan-HER inhibitor for advanced non-small-cell lung cancer (NSCLC). We explored the impact of a planned 4-day dacomitinib dose interruption on plasma exposure of dacomitinib and adverse events (AEs) of interest in Cohort III of the ARCHER 1042 study. Materials and methods Patients, treatment-naïve for advanced NSCLC with EGFR activating mutations, received oral dacomitinib 45 mg QD (once daily). A planned dose interruption occurred in Cycle 1 from Days 11 through 14. The primary endpoint was the pharmacokinetic (PK) characteristics of dacomitinib in Cycle 1 Day 10 and during dose interruption. Secondary endpoints included safety and concomitant medications used to treat AEs of interest. Results Cohort III enrolled 25 patients. Median plasma Cmax of dacomitinib in Cycle 1 Day 10 was 83.40 ng/mL. Average median plasma dacomitinib concentration during the 4-day dose interruption was 42.63 ng/mL. In the first 8 weeks of treatment 1) 80% of patients used concomitant medications for dermatologic AEs, 76% for diarrhea, and 44% for stomatitis, and 2) all patients experienced treatment-emergent AEs and 28% had all-causality Grade 3 AEs. Conclusion At 45 mg QD dosing, PK parameters of plasma dacomitinib in Cycle 1 Day 10 were comparable to that obtained in Cycle 1 Day 14 from other dacomitinib studies. Average median plasma dacomitinib concentration during the 4-day dose interruption was approximately half of the median plasma Cmax of dacomitinib observed prior to dose interruption. The toxicity profile was consistent with that from other studies of dacomitinib. PMID:28285698
Daga, Haruko; Takeda, Koji; Okada, Hideaki; Miyazaki, Masaki; Ueda, Shinya; Kaneda, Hiroyasu; Okamoto, Isamu; Yoh, Kiyotaka; Goto, Koichi; Konishi, Koichi; Sarashina, Akiko; Tanaka, Tetsuya; Kaiser, Rolf; Nakagawa, Kazuhiko
2015-12-01
This open-label, phase I, dose-escalation part of a phase I/II study evaluated the safety, pharmacokinetics, and preliminary efficacy of nintedanib, a triple angiokinase inhibitor, combined with pemetrexed in Japanese patients with advanced non-small cell lung cancer (NSCLC) after first-line chemotherapy. A fixed dose of pemetrexed (500 mg/m(2) iv) was administered on Day 1 of each 21-day cycle followed by oral nintedanib twice daily (bid) on days 2-21, starting at 100 mg bid and escalating to 200 mg bid in 50-mg intervals, using a standard 3 + 3 design. After ≥4 cycles of combination therapy, patients could continue nintedanib monotherapy until disease progression or undue adverse events (AEs). Primary endpoints were maximum tolerated dose (MTD), defined as the highest dose at which the incidence of dose-limiting toxicities (DLTs) was <33.3 % during the first treatment course, and AEs (CTCAE v3.0). DLTs were primarily defined as grade ≥3 non-hematologic or grade 4 hematologic AEs. Eighteen patients were included in the analysis. DLTs were experienced by 2/9 patients receiving 200 mg bid, 1/6 receiving 150 mg bid, and 0/3 receiving the lowest dose. The MTD of nintedanib plus pemetrexed was 200 mg bid. The most common drug-related AEs were elevated liver enzymes and gastrointestinal AEs. Two patients achieved partial response, and 10 had stable disease. Nintedanib plus pemetrexed had a manageable safety profile and showed promising signs of efficacy in previously treated Japanese patients with advanced NSCLC. As in Caucasian patients, the MTD of nintedanib was 200 mg bid. Clinical trial information NCT00979576.
Ponce, Francisco A; Asaad, Wael F; Foote, Kelly D; Anderson, William S; Rees Cosgrove, G; Baltuch, Gordon H; Beasley, Kara; Reymers, Donald E; Oh, Esther S; Targum, Steven D; Smith, Gwenn S; Lyketsos, Constantine G; Lozano, Andres M
2016-07-01
OBJECT This report describes the stereotactic technique, hospitalization, and 90-day perioperative safety of bilateral deep brain stimulation (DBS) of the fornix in patients who underwent DBS for the treatment of mild, probable Alzheimer's disease (AD). METHODS The ADvance Trial is a multicenter, 12-month, double-blind, randomized, controlled feasibility study being conducted to evaluate the safety, efficacy, and tolerability of DBS of the fornix in patients with mild, probable AD. Intraoperative and perioperative data were collected prospectively. All patients underwent postoperative MRI. Stereotactic analyses were performed in a blinded fashion by a single surgeon. Adverse events (AEs) were reported to an independent clinical events committee and adjudicated to determine the relationship between the AE and the study procedure. RESULTS Between June 6, 2012, and April 28, 2014, a total of 42 patients with mild, probable AD were treated with bilateral fornix DBS (mean age 68.2 ± 7.8 years; range 48.0-79.7 years; 23 men and 19 women). The mean planned target coordinates were x = 5.2 ± 1.0 mm (range 3.0-7.9 mm), y = 9.6 ± 0.9 mm (range 8.0-11.6 mm), z = -7.5 ± 1.2 mm (range -5.4 to -10.0 mm), and the mean postoperative stereotactic radial error on MRI was 1.5 ± 1.0 mm (range 0.2-4.0 mm). The mean length of hospitalization was 1.4 ± 0.8 days. Twenty-six (61.9%) patients experienced 64 AEs related to the study procedure, of which 7 were serious AEs experienced by 5 patients (11.9%). Four (9.5%) patients required return to surgery: 2 patients for explantation due to infection, 1 patient for lead repositioning, and 1 patient for chronic subdural hematoma. No patients experienced neurological deficits as a result of the study, and no deaths were reported. CONCLUSIONS Accurate targeting of DBS to the fornix without direct injury to it is feasible across surgeons and treatment centers. At 90 days after surgery, bilateral fornix DBS was well tolerated by patients with mild, probable AD. Clinical trial registration no.: NCT01608061 ( clinicaltrials.gov ).
Ponce, Francisco A.; Asaad, Wael F.; Foote, Kelly D.; Anderson, William S.; Cosgrove, G. Rees; Baltuch, Gordon H.; Beasley, Kara; Reymers, Donald E.; Oh, Esther S.; Targum, Steven D.; Smith, Gwenn S.; Lyketsos, Constantine G.; Lozano, Andres M.
2016-01-01
OBJECT This report describes the stereotactic technique, hospitalization, and 90-day perioperative safety of bilateral deep brain stimulation (DBS) of the fornix in patients who underwent DBS for the treatment of mild, probable Alzheimer’s disease (AD). METHODS The ADvance Trial is a multicenter, 12-month, double-blind, randomized, controlled feasibility study being conducted to evaluate the safety, efficacy, and tolerability of DBS of the fornix in patients with mild, probable AD. Intra-operative and perioperative data were collected prospectively. All patients underwent postoperative MRI. Stereotactic analyses were performed in a blinded fashion by a single surgeon. Adverse events (AEs) were reported to an independent clinical events committee and adjudicated to determine the relationship between the AE and the study procedure. RESULTS Between June 6, 2012, and April 28, 2014, a total of 42 patients with mild, probable AD were treated with bilateral fornix DBS (mean age 68.2 ± 7.8 years; range 48.0–79.7 years; 23 men and 19 women). The mean planned target coordinates were x = 5.2 ± 1.0 mm (range 3.0–7.9 mm), y = 9.6 ± 0.9 mm (range 8.0–11.6 mm), z = −7.5 ± 1.2 mm (range −5.4 to −10.0 mm), and the mean postoperative stereotactic radial error on MRI was 1.5 ± 1.0 mm (range 0.2–4.0 mm). The mean length of hospitalization was 1.4 ± 0.8 days. Twenty-six (61.9%) patients experienced 64 AEs related to the study procedure, of which 7 were serious AEs experienced by 5 patients (11.9%). Four (9.5%) patients required return to surgery: 2 patients for explantation due to infection, 1 patient for lead repositioning, and 1 patient for chronic subdural hematoma. No patients experienced neurological deficits as a result of the study, and no deaths were reported. CONCLUSIONS Accurate targeting of DBS to the fornix without direct injury to it is feasible across surgeons and treatment centers. At 90 days after surgery, bilateral fornix DBS was well tolerated by patients with mild, probable AD. PMID:26684775
An adaptive technique for estimating the atmospheric density profile during the AE mission
NASA Technical Reports Server (NTRS)
Argentiero, P.
1973-01-01
A technique is presented for processing accelerometer data obtained during the AE missions in order to estimate the atmospheric density profile. A minimum variance, adaptive filter is utilized. The trajectory of the probe and probe parameters are in a consider mode where their estimates are unimproved but their associated uncertainties are permitted an impact on filter behavior. Simulations indicate that the technique is effective in estimating a density profile to within a few percentage points.
NASA Technical Reports Server (NTRS)
Watson, David; Knox, James C.; West, Phillip; Stanley, Christine M.; Bush, Richard
2015-01-01
The Life Support Systems Project (LSSP) under the Advanced Exploration Systems (AES) program builds upon the work performed under the AES Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project focusing on the numerous technology development areas. The CO2 removal and associated air drying development efforts are focused on improving the current state-of-the-art system on the International Space Station (ISS) utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. A component of the CO2 removal effort encompasses structural stability testing of existing and emerging sorbents. Testing will be performed on dry sorbents and sorbents that have been conditioned to three humidity levels. This paper describes the sorbent structural stability screening efforts in support of the LSS Project within the AES Program.
Generalized Majority Logic Criterion to Analyze the Statistical Strength of S-Boxes
NASA Astrophysics Data System (ADS)
Hussain, Iqtadar; Shah, Tariq; Gondal, Muhammad Asif; Mahmood, Hasan
2012-05-01
The majority logic criterion is applicable in the evaluation process of substitution boxes used in the advanced encryption standard (AES). The performance of modified or advanced substitution boxes is predicted by processing the results of statistical analysis by the majority logic criteria. In this paper, we use the majority logic criteria to analyze some popular and prevailing substitution boxes used in encryption processes. In particular, the majority logic criterion is applied to AES, affine power affine (APA), Gray, Lui J, residue prime, S8 AES, Skipjack, and Xyi substitution boxes. The majority logic criterion is further extended into a generalized majority logic criterion which has a broader spectrum of analyzing the effectiveness of substitution boxes in image encryption applications. The integral components of the statistical analyses used for the generalized majority logic criterion are derived from results of entropy analysis, contrast analysis, correlation analysis, homogeneity analysis, energy analysis, and mean of absolute deviation (MAD) analysis.
NASA Astrophysics Data System (ADS)
Various papers on AE from composite materials are presented. Among the individual topics addressed are: acoustic analysis of tranverse lamina cracking in CFRP laminates under tensile loading, characterization of fiber failure in graphite-epoxy (G/E) composites, application of AE in the study of microfissure damage to composite used in the aeronautic and space industries, interfacial shear properties and AE behavior of model aluminum and titanium matrix composites, amplitude distribution modelling and ultimate strength prediction of ASTM D-3039 G/E tensile specimens, AE prefailure warning system for composite structural tests, characterization of failure mechanisms in G/E tensile tests specimens using AE data, development of a standard testing procedure to yield an AE vs. strain curve, benchmark exercise on AE measurements from carbon fiber-epoxy composites. Also discussed are: interpretation of optically detected AE signals, acoustic emission monitoring of fracture process of SiC/Al composites under cyclic loading, application of pattern recognition techniques to acousto-ultrasonic testing of Kevlar composite panels, AE for high temperature monitoring of processing of carbon/carbon composite, monitoring the resistance welding of thermoplastic composites through AE, plate wave AE composite materials, determination of the elastic properties of composite materials using simulated AE signals, AE source location in thin plates using cross-correlation, propagation of flexural mode AE signals in Gr/Ep composite plates.
NASA Astrophysics Data System (ADS)
Niccolini, Gianni; Manuello, Amedeo; Marchis, Elena; Carpinteri, Alberto
2017-07-01
The stability of an arch as a structural element in the thermal bath of King Charles Albert (Carlo Alberto) in the Royal Castle of Racconigi (on the UNESCO World Heritage List since 1997) was assessed by the acoustic emission (AE) monitoring technique with application of classical inversion methods to recorded AE data. First, damage source location by means of triangulation techniques and signal frequency analysis were carried out. Then, the recently introduced method of natural-time analysis was preliminarily applied to the AE time series in order to reveal a possible entrance point to a critical state of the monitored structural element. Finally, possible influence of the local seismic and microseismic activity on the stability of the monitored structure was investigated. The criterion for selecting relevant earthquakes was based on the estimation of the size of earthquake preparation zones. The presented results suggest the use of the AE technique as a tool for detecting both ongoing structural damage processes and microseismic activity during preparation stages of seismic events.
Tyree, Melvin T.; Dixon, Michael A.; Thompson, Robert G.
1984-01-01
An improved method of counting acoustic emission (AE) events from water-stressed stems of cedar (Thuja occidentalis L.) is presented. Amplified AEs are analyzed on a real time basis by a microcomputer. The instrumentation counts AE events in a fashion nearly analogous to scintillation counting of radioactive materials. The technique was applied to measuring ultrasonic AEs from the stems of cedar inside a pressure bomb. The shoots were originally fully hydrated. When the shoots are dehydrated in the bomb by application of an overpressure very few AEs were detected. When the bomb pressure is reduced after dehydration of the shoot, AE events could be detected. We conclude that ultrasonic AEs are caused by cavitation events (= structural breakdown of water columns in the tracheids of cedar) and not by the breaking of cellulose fibers in the wood. PMID:16663501
NASA Astrophysics Data System (ADS)
Flynn, J. William; Goodfellow, Sebastian; Reyes-Montes, Juan; Nasseri, Farzine; Young, R. Paul
2016-04-01
Continuous acoustic emission (AE) data recorded during rock deformation tests facilitates the monitoring of fracture initiation and propagation due to applied stress changes. Changes in the frequency and energy content of AE waveforms have been previously observed and were associated with microcrack coalescence and the induction or mobilisation of large fractures which are naturally associated with larger amplitude AE events and lower-frequency components. The shift from high to low dominant frequency components during the late stages of the deformation experiment, as the rate of AE events increases and the sample approaches failure, indicates a transition from the micro-cracking to macro-cracking regime, where large cracks generated result in material failure. The objective of this study is to extract information on the fracturing process from the acoustic records around sample failure, where the fast occurrence of AE events does not allow for identification of individual AE events and phase arrivals. Standard AE event processing techniques are not suitable for extracting this information at these stages. Instead the observed changes in the frequency content of the continuous record can be used to characterise and investigate the fracture process at the stage of microcrack coalescence and sample failure. To analyse and characterise these changes, a detailed non-linear and non-stationary time-frequency analysis of the continuous waveform data is required. Empirical Mode Decomposition (EMD) and Hilbert Spectral Analysis (HSA) are two of the techniques used in this paper to analyse the acoustic records which provide a high-resolution temporal frequency distribution of the data. In this paper we present the results from our analysis of continuous AE data recorded during a laboratory triaxial deformation experiment using the combined EMD and HSA method.
Finite element modeling of wave propagation in concrete.
DOT National Transportation Integrated Search
2008-09-01
Three reports were produced from research sponsored by the Oregon Department of Transportation on acoustic emission (AE). The first describes the evaluation of AE techniques applied to two reinforced concrete (RC) bridge girders, which were loaded to...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hansen, Randy R.; Bass, Robert B.; Kouzes, Richard T.
2003-01-20
This paper provides a brief overview of the implementation of the Advanced Encryption Standard (AES) as a hash function for confirming the identity of software resident on a computer system. The PNNL Software Authentication team chose to use a hash function to confirm software identity on a system for situations where: (1) there is limited time to perform the confirmation and (2) access to the system is restricted to keyboard or thumbwheel input and output can only be displayed on a monitor. PNNL reviewed three popular algorithms: the Secure Hash Algorithm - 1 (SHA-1), the Message Digest - 5 (MD-5),more » and the Advanced Encryption Standard (AES) and selected the AES to incorporate in software confirmation tool we developed. This paper gives a brief overview of the SHA-1, MD-5, and the AES and sites references for further detail. It then explains the overall processing steps of the AES to reduce a large amount of generic data-the plain text, such is present in memory and other data storage media in a computer system, to a small amount of data-the hash digest, which is a mathematically unique representation or signature of the former that could be displayed on a computer's monitor. This paper starts with a simple definition and example to illustrate the use of a hash function. It concludes with a description of how the software confirmation tool uses the hash function to confirm the identity of software on a computer system.« less
Wireless AE Event and Environmental Monitoring for Wind Turbine Blades at Low Sampling Rates
NASA Astrophysics Data System (ADS)
Bouzid, Omar M.; Tian, Gui Y.; Cumanan, K.; Neasham, J.
Integration of acoustic wireless technology in structural health monitoring (SHM) applications introduces new challenges due to requirements of high sampling rates, additional communication bandwidth, memory space, and power resources. In order to circumvent these challenges, this chapter proposes a novel solution through building a wireless SHM technique in conjunction with acoustic emission (AE) with field deployment on the structure of a wind turbine. This solution requires a low sampling rate which is lower than the Nyquist rate. In addition, features extracted from aliased AE signals instead of reconstructing the original signals on-board the wireless nodes are exploited to monitor AE events, such as wind, rain, strong hail, and bird strike in different environmental conditions in conjunction with artificial AE sources. Time feature extraction algorithm, in addition to the principal component analysis (PCA) method, is used to extract and classify the relevant information, which in turn is used to classify or recognise a testing condition that is represented by the response signals. This proposed novel technique yields a significant data reduction during the monitoring process of wind turbine blades.
Li, Dongsheng; Cao, Hai
2012-01-01
The applicability of acoustic emission (AE) techniques to monitor the mechanism of evolution of polyvinyl alcohol (PVA) fiber concrete damage under temperature fatigue loading is investigated. Using the temperature fatigue test, real-time AE monitoring data of PVA fiber concrete is achieved. Based on the AE signal characteristics of the whole test process and comparison of AE signals of PVA fiber concretes with different fiber contents, the damage evolution process of PVA fiber concrete is analyzed. Finally, a qualitative evaluation of the damage degree is obtained using the kurtosis index and b-value of AE characteristic parameters. The results obtained using both methods are discussed.
Li, Dongsheng; Cao, Hai
2012-01-01
The applicability of acoustic emission (AE) techniques to monitor the mechanism of evolution of polyvinyl alcohol (PVA) fiber concrete damage under temperature fatigue loading is investigated. Using the temperature fatigue test, real-time AE monitoring data of PVA fiber concrete is achieved. Based on the AE signal characteristics of the whole test process and comparison of AE signals of PVA fiber concretes with different fiber contents, the damage evolution process of PVA fiber concrete is analyzed. Finally, a qualitative evaluation of the damage degree is obtained using the kurtosis index and b-value of AE characteristic parameters. The results obtained using both methods are discussed. PMID:23012555
AE characteristic for monitoring of fatigue crack in steel bridge members
NASA Astrophysics Data System (ADS)
Yoon, Dong-Jin; Jung, Juong-Chae; Park, Philip; Lee, Seung-Seok
2000-06-01
Acoustic emission technique was employed for the monitoring of crack activity in both steel bridge members and laboratory specimen. Laboratory experiment was carried out to identify AE characteristics of fatigue cracks for compact tension specimen. The relationship between a stress intensity factor and AE signals activity as well as conventional AE parameter analysis was discussed. A field test was also conducted on a railway bridge, which contain several fatigue cracks. Crack activities were investigated while in service with strain measurement. From the results, in the laboratory tests, the features of three parameters such as the length of crack growth, the AE energy, and the cumulative AE events, showed the almost same trend in their increase as the number of fatigue cycle increased. From the comparisons of peak amplitude and AE energy with stress intensity factor, it was verified that the higher stress intensity factors generated AE signals with higher peak amplitude and a large number of AE counts. In the field test, real crack propagation signals were captured and the crack activity was verified in two cases.
Efficacy of Advanced Odomos repellent cream (N, N-diethyl-benzamide) against mosquito vectors.
Mittal, P K; Sreehari, U; Razdan, R K; Dash, A P; Ansari, M A
2011-04-01
Repellents are commonly used personal protection measures to avoid mosquito bites. In the present study, Advanced Odomos cream (12% N, N-diethyl-benzamide) was tested for its efficacy against mosquitoes in comparison to DEET (N,N-diethyl-3-methyl benzamide). Bioassays were conducted to assess the repellency of Advanced Odomos and DEET creams against Anopheles stephensi and Aedes aegypti. Their efficacy was tested on human volunteers applied with different concentrations of test creams ranging from 1 to 12 mg/cm 2 and by exposing them to mosquitoes at hourly intervals. Field evaluation was also carried out to test the duration of protection of the test creams against Anopheles and Aedes mosquitoes during whole night and day time collections, respectively on human volunteers. Mosquito collections were done using torch light and aspirator. Complete (100%) protection was achieved at 10 mg/cm 2 cream formulation of Advanced Odomos (1.2 mg a.i/cm 2 ) dose against An. stephensi and 12 mg/cm 2 (1.44 mg a.i./cm 2 ) against Ae. aegypti on human baits. There was no statistically significant differences in per cent protection against mosquito bites between Advanced Odomos and DEET cream (P>0.05) in respective doses. Complete protection up to 11 h was observed against Anopheles mosquitoes during whole night collections and up to 6 h against Ae. aegypti in day time collections. No adverse reactions such as itching, irritation, vomiting, nausea, etc. were reported by the volunteers. Advanced Odomos cream applied at 10 mg/cm 2 concentration provided 100% protection from Anopheles mosquitoes up to 11 h whereas about 6 h protection was recorded against Ae. aegypti. The laboratory and field trials indicate that for longer protection against Anopheles mosquitoes 10 mg/cm 2 will be appropriate and in case of Ae. aegypti more than 10 mg/cm 2 application is required for complete protection. In conclusion, the Advanced Odomos cream was comparable to the known repellent cream DEET for prolonged protection against malaria and dengue vectors.
NASA Astrophysics Data System (ADS)
Ma, Gao; Li, Hui; Zhou, Wensong; Xian, Guijun
2012-04-01
Acoustic emission (AE) technique is an effective method in the nondestructive testing (NDT) field of civil engineering. During the last two decades, Fiber reinforced polymer (FRP) has been widely used in repairing and strengthening concrete structures. The damage state of FRP strengthened concrete structures has become an important issue during the service period of the structure and it is a meaningful work to use AE technique as a nondestructive method to assess its damage state. The present study reports AE monitoring results of axial compression tests carried on basalt fiber reinforced polymer (BFRP) confined concrete columns and three-point-bending tests carried on BFRP reinforced concrete beams. AE parameters analysis was firstly utilized to give preliminary results of the concrete fracture process of these specimens. It was found that cumulative AE events can reflect the fracture development trend of both BFRP confined concrete columns and BFRP strengthened concrete beams and AE events had an abrupt increase at the point of BFRP breakage. Then the fracture process of BFRP confined concrete columns and BFRP strengthened concrete beams was studied through RA value-average frequency analysis. The RA value-average frequency tendencies of BFRP confined concrete were found different from that of BFRP strengthened concrete beams. The variation tendency of concrete crack patterns during the loading process was revealed.
NASA Astrophysics Data System (ADS)
Qiu, Junchao; Zhang, Lin; Li, Diyang; Liu, Xingcheng
2016-06-01
Chaotic sequences can be applied to realize multiple user access and improve the system security for a visible light communication (VLC) system. However, since the map patterns of chaotic sequences are usually well known, eavesdroppers can possibly derive the key parameters of chaotic sequences and subsequently retrieve the information. We design an advanced encryption standard (AES) interleaving aided multiple user access scheme to enhance the security of a chaotic code division multiple access-based visible light communication (C-CDMA-VLC) system. We propose to spread the information with chaotic sequences, and then the spread information is interleaved by an AES algorithm and transmitted over VLC channels. Since the computation complexity of performing inverse operations to deinterleave the information is high, the eavesdroppers in a high speed VLC system cannot retrieve the information in real time; thus, the system security will be enhanced. Moreover, we build a mathematical model for the AES-aided VLC system and derive the theoretical information leakage to analyze the system security. The simulations are performed over VLC channels, and the results demonstrate the effectiveness and high security of our presented AES interleaving aided chaotic CDMA-VLC system.
Comments on the origin of acoustic emission in fatigue testing of aluminum alloys
NASA Astrophysics Data System (ADS)
Heiple, C. R.; Carpenter, S. H.; Armentrout, D. L.
The size of acoustic emission (AE) signals expected from inclusion fracture during fatigue testing of 7075 aluminum has been estimated on the basis of previous measurements of AE produced by the fracture of boron particles incorporated into 2219 aluminum. The AF signal size expected from deformation in the plastic zone ahead of the fatigue crack was estimated from the results of tensile tests on 7075 aluminum. The signals predicted from both processes are near or below the noise level in the fatigue experiments and are therefore far too small to account for the signals actually observed. Nearly simultaneous fracture of multiple inclusions could produce signals as large as those observed in fatigue tests of 7075 aluminum, however, fatigue tests of 7050 aluminum produced signals as large or larger than in 7075. Since 7050 has substantially fewer inclusions than 7075, the simultaneous failure of multiple inclusions is unlikely to be a major AE source in fatigue testing of either aluminum alloy. Thus, the most probable source of acoustic emission during fatigue testing of 7075 and 7050 aluminum is the crack advance itself. The measured crack advance per cycle is large enough to release sufficient elastic energy to account for the AE signals observed.
McCarthy, Moira M.; Tucker, Scott; Nguyen, Joseph T.; Green, Daniel W.; Imhauser, Carl W.; Cordasco, Frank A.
2014-01-01
Background Anterior cruciate ligament (ACL) injuries are an increasingly recognized problem in the pediatric population. Unfortunately, outcomes with conservative treatment are extremely poor. Furthermore, adult reconstruction techniques may be inappropriate to treat skeletally immature patients due to the risk of physeal complications. “Physeal-sparing” reconstruction techniques exist but their ability to restore knee stability and contact mechanics is not well understood. Purpose (1) To assess the ability of the all-epiphyseal (AE) and over-the-top (OT) reconstructions to restore knee kinematics; (2) to assess whether these reconstructions decrease the high posterior contact stresses seen with ACL deficiency; (3) to determine whether the AE or OT produce abnormal tibiofemoral contact stresses. Hypothesis The AE reconstruction will restore contact mechanics and kinematics similarly to that of the ACL intact knee. Methods Ten fresh-frozen human cadaveric knees were tested using a robotic manipulator. Tibiofemoral motions were recorded with the ACL intact, after sectioning the ACL, and after both reconstructions in each of the 10 specimens. The AE utilized an all-inside technique with tunnels exclusively within the epiphysis and fixed with suspensory cortical fixation devices. The OT had a central and vertical tibial tunnel with an over-the-top femur position and was fixed with staples and posts on both ends. Anterior stability was assessed with 134N anterior force at 0, 15, 30, 60, and 90° of knee flexion. Rotational stability was assessed with combined 8 Nm and 4 Nm of abduction and internal rotation, respectively, at 5, 15, and 30° of knee flexion. Results Both reconstruction techniques offloaded the posterior aspect of the tibial plateau compared to the ACL deficient knee in response to both anterior loads and combined moments as demonstrated by reduced contact stresses in this region at all flexion angles. Compared to the ACL intact condition, both the AE and OT had increased posteromedial contact stresses in response to anterior load at some flexion angles and the OT had increased peripheral posterolateral contact stresses at 15° in response to combined moments. Neither reconstruction completely restored the mid-joint contact stresses. Both reconstruction techniques restored anterior stability at flexion angles less than or equal to 30°. In contrast, neither reconstruction restored anterior stability at 60 and 90° flexion. Both reconstructions restored coupled anterior translation under combined moments. Additionally, the AE over-constrained internal rotation in response to the combined moments by 12% at 15° flexion. Conclusions Both reconstructions provide anterior and rotational stability, and decrease posterior joint contact stresses compared to the ACL deficient knee. However, neither reconstruction restored the contact mechanics and kinematics of the ACL intact knee. Clinical Relevance Since the AE reconstruction has clinical advantages over the OT, our results support the hypothesis that the new AE technique is a potential candidate for use in the skeletally immature athlete. PMID:23613444
Yamazaki, Naoya; Kiyohara, Yoshio; Uhara, Hisashi; Uehara, Jiro; Fujimoto, Manabu; Takenouchi, Tatsuya; Otsuka, Masaki; Uchi, Hiroshi; Ihn, Hironobu; Minami, Hironobu
2017-06-01
Treating advanced or recurrent melanoma remains a challenge. Cancer cells can evade the immune system by blocking T-cell activation through overexpression of the inhibitory receptor programmed death 1 (PD-1) ligands. The PD-1 inhibitor nivolumab blocks the inhibitory signal in T cells, thus overcoming the immune resistance of cancer cells. Nivolumab has shown promising anticancer activity in various cancers. We carried out a single-arm, open-label, multicenter, phase II study to investigate the efficacy and safety of nivolumab in previously untreated Japanese patients with advanced melanoma. Twenty-four patients with stage III/IV or recurrent melanoma were enrolled and received i.v. nivolumab 3 mg/kg every 2 weeks until disease progression or unacceptable toxicity. The primary endpoint was overall response rate evaluated by an independent radiology review committee. The independent radiology review committee-assessed overall response rate was 34.8% (90% confidence interval, 20.8-51.9), and the overall survival rate at 18 months was 56.5% (90% confidence interval, 38.0-71.4). Treatment-related adverse events (AEs) of grade 3 or 4 only occurred in three patients (12.5%). Two patients discontinued nivolumab because of AEs, but all AEs were considered manageable by early diagnosis and appropriate treatment. Subgroup analyses showed that nivolumab was clinically beneficial and tolerable regardless of BRAF genotype, and that patients with treatment-related select AEs and with vitiligo showed tendency for better survival. In conclusion, nivolumab showed favorable efficacy and safety profiles in Japanese patients with advanced or recurrent melanoma, with or without BRAF mutations. (Trial registration no. JapicCTI-142533.). © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.
[Hybrids of Aegilops cylindrica Host with Triticum durum Desf. and T. aestivum L].
Avsenin, V I; Motsnyĭ, A I; Rybalka, A I; Faĭt, V I
2003-01-01
The hybrids of durum and bread wheat with Ae. cylindrica have been obtained without using an embryo rescue technique. The hybrid output (of pollinated flower number) in the field conditions scored 1.0, 15.3 and 10.0% in the crosses T. durum x Ae. cylindrica, Ae. cylindrica x T. durum and T. aestivum x Ae. cylindrica, respectively. A high level of meiotic chromosome pairing between homologous D genomes of bread wheat and Aegilops has been revealed (c = 80.0-83.7%). The possibility of homoeological pairing between wheat and Ae. cylindrica chromosomes has been shown. Herewith, the correlation between the levels of homological and homoeological pairing is absent. The possibilities of genetic material interchange, including between the tetraploid species, as well as the using of Ae. cylindrica cytoplasm for durum wheat breeding are discussed.
Pickwell, Andrew J; Dorey, Robert A; Mba, David
2011-09-01
Monitoring the condition of complex engineering structures is an important aspect of modern engineering, eliminating unnecessary work and enabling planned maintenance, preventing failure. Acoustic emissions (AE) testing is one method of implementing continuous nondestructive structural health monitoring. A novel thick-film (17.6 μm) AE sensor is presented. Lead zirconate titanate thick films were fabricated using a powder/sol composite ink deposition technique and mechanically patterned to form a discrete thick-film piezoelectric AE sensor. The thick-film sensor was benchmarked against a commercial AE device and was found to exhibit comparable responses to simulated acoustic emissions.
Wirtz, Sebastian F; Cunha, Adauto P A; Labusch, Marc; Marzun, Galina; Barcikowski, Stephan; Söffker, Dirk
2018-06-01
Today, the demand for continuous monitoring of valuable or safety critical equipment is increasing in many industrial applications due to safety and economical requirements. Therefore, reliable in-situ measurement techniques are required for instance in Structural Health Monitoring (SHM) as well as process monitoring and control. Here, current challenges are related to the processing of sensor data with a high data rate and low latency. In particular, measurement and analyses of Acoustic Emission (AE) are widely used for passive, in-situ inspection. Advantages of AE are related to its sensitivity to different micro-mechanical mechanisms on the material level. However, online processing of AE waveforms is computationally demanding. The related equipment is typically bulky, expensive, and not well suited for permanent installation. The contribution of this paper is the development of a Field Programmable Gate Array (FPGA)-based measurement system using ZedBoard devlopment kit with Zynq-7000 system on chip for embedded implementation of suitable online processing algorithms. This platform comprises a dual-core Advanced Reduced Instruction Set Computer Machine (ARM) architecture running a Linux operating system and FPGA fabric. A FPGA-based hardware implementation of the discrete wavelet transform is realized to accelerate processing the AE measurements. Key features of the system are low cost, small form factor, and low energy consumption, which makes it suitable to serve as field-deployed measurement and control device. For verification of the functionality, a novel automatically realized adjustment of the working distance during pulsed laser ablation in liquids is established as an example. A sample rate of 5 MHz is achieved at 16 bit resolution.
Crack classification in concrete beams using AE parameters
NASA Astrophysics Data System (ADS)
Bahari, N. A. A. S.; Shahidan, S.; Abdullah, S. R.; Ali, N.; Zuki, S. S. Mohd; Ibrahim, M. H. W.; Rahim, M. A.
2017-11-01
The acoustic emission (AE) technique is an effective tool for the evaluation of crack growth. The aim of this study is to evaluate crack classification in reinforced concrete beams using statistical analysis. AE has been applied for the early monitoring of reinforced concrete structures using AE parameters such as average frequency, rise time, amplitude counts and duration. This experimental study focuses on the utilisation of this method in evaluating reinforced concrete beams. Beam specimens measuring 150 mm × 250 mm × 1200 mm were tested using a three-point load flexural test using Universal Testing Machines (UTM) together with an AE monitoring system. The results indicated that RA value can be used to determine the relationship between tensile crack and shear movement in reinforced concrete beams.
Scholey, J J; Wilcox, P D; Wisnom, M R; Friswell, M I
2009-06-01
A model for quantifying the performance of acoustic emission (AE) systems on plate-like structures is presented. Employing a linear transfer function approach the model is applicable to both isotropic and anisotropic materials. The model requires several inputs including source waveforms, phase velocity and attenuation. It is recognised that these variables may not be readily available, thus efficient measurement techniques are presented for obtaining phase velocity and attenuation in a form that can be exploited directly in the model. Inspired by previously documented methods, the application of these techniques is examined and some important implications for propagation characterisation in plates are discussed. Example measurements are made on isotropic and anisotropic plates and, where possible, comparisons with numerical solutions are made. By inputting experimentally obtained data into the model, quantitative system metrics are examined for different threshold values and sensor locations. By producing plots describing areas of hit success and source location error, the ability to measure the performance of different AE system configurations is demonstrated. This quantitative approach will help to place AE testing on a more solid foundation, underpinning its use in industrial AE applications.
Beamforming array techniques for acoustic emission monitoring of large concrete structures
NASA Astrophysics Data System (ADS)
McLaskey, Gregory C.; Glaser, Steven D.; Grosse, Christian U.
2010-06-01
This paper introduces a novel method of acoustic emission (AE) analysis which is particularly suited for field applications on large plate-like reinforced concrete structures, such as walls and bridge decks. Similar to phased-array signal processing techniques developed for other non-destructive evaluation methods, this technique adapts beamforming tools developed for passive sonar and seismological applications for use in AE source localization and signal discrimination analyses. Instead of relying on the relatively weak P-wave, this method uses the energy-rich Rayleigh wave and requires only a small array of 4-8 sensors. Tests on an in-service reinforced concrete structure demonstrate that the azimuth of an artificial AE source can be determined via this method for sources located up to 3.8 m from the sensor array, even when the P-wave is undetectable. The beamforming array geometry also allows additional signal processing tools to be implemented, such as the VESPA process (VElocity SPectral Analysis), whereby the arrivals of different wave phases are identified by their apparent velocity of propagation. Beamforming AE can reduce sampling rate and time synchronization requirements between spatially distant sensors which in turn facilitates the use of wireless sensor networks for this application.
Comparative efficacy of existing surveillance tools for Aedes aegypti in Western Kenya.
Yalwala, Sancto; Clark, Jeffrey; Oullo, David; Ngonga, Daniel; Abuom, David; Wanja, Elizabeth; Bast, Joshua
2015-12-01
All traditional surveillance techniques for Aedes aegypti have been developed for the cosmopolitan domestic subspecies Ae. aegypti aegypti, and not the sylvatic subspecies, Ae. aegypti formosus. The predominant form in Western Kenya is Ae. aegypti formosus that is rarely associated with human habitations but is linked to transmission of sylvatic dengue virus strains. We compared five surveillance methods for their effectiveness in sampling Ae. aegypti formosus with the goal of determining a sustainable surveillance strategy in Kenya. The methods included larval and pupal surveys, oviposition trapping, BG-Sentinel trapping, resting boxes, and backpack aspirations. Larval and pupal surveys collected the highest number of Ae. aegypti formosus (51.3%), followed by oviposition traps (45.7%), BG-Sentinel traps (3.0%), and zero collected with either backpack aspiration or resting box collections. No Ae. aegypti formosus larvae or pupae were found indoors. The results indicate that oviposition traps and outdoor larval and pupal surveys were better surveillance methods for Ae. aegypti formosus in Western Kenya. © 2015 The Society for Vector Ecology.
FRP/steel composite damage acoustic emission monitoring and analysis
NASA Astrophysics Data System (ADS)
Li, Dongsheng; Chen, Zhi
2015-04-01
FRP is a new material with good mechanical properties, such as high strength of extension, low density, good corrosion resistance and anti-fatigue. FRP and steel composite has gotten a wide range of applications in civil engineering because of its good performance. As the FRP/steel composite get more and more widely used, the monitor of its damage is also getting more important. To monitor this composite, acoustic emission (AE) is a good choice. In this study, we prepare four identical specimens to conduct our test. During the testing process, the AE character parameters and mechanics properties were obtained. Damaged properties of FRP/steel composite were analyzed through acoustic emission (AE) signals. By the growing trend of AE accumulated energy, the severity of the damage made on FRP/steel composite was estimated. The AE sentry function has been successfully used to study damage progression and fracture emerge release rate of composite laminates. This technique combines the cumulative AE energy with strain energy of the material rather than analyzes the AE information and mechanical separately.
Performance analysis of AES-Blowfish hybrid algorithm for security of patient medical record data
NASA Astrophysics Data System (ADS)
Mahmud H, Amir; Angga W, Bayu; Tommy; Marwan E, Andi; Siregar, Rosyidah
2018-04-01
A file security is one method to protect data confidentiality, integrity and information security. Cryptography is one of techniques used to secure and guarantee data confidentiality by doing conversion to the plaintext (original message) to cipher text (hidden message) with two important processes, they are encrypt and decrypt. Some researchers proposed a hybrid method to improve data security. In this research we proposed hybrid method of AES-blowfish (BF) to secure the patient’s medical report data into the form PDF file that sources from database. Generation method of private and public key uses two ways of approach, those are RSA method f RSA and ECC. We will analyze impact of these two ways of approach for hybrid method at AES-blowfish based on time and Throughput. Based on testing results, BF method is faster than AES and AES-BF hybrid, however AES-BF hybrid is better for throughput compared with AES and BF is higher.
Chang, Yen-Hsiang; Yu, Jin-Jie; Lin, Chun-Li
2014-12-13
This study investigates CAD/CAM ceramic cusp-replacing restoration resistance with and without buccal cusp replacement under static and dynamic cyclic loads, monitored using the acoustic emission (AE) technique. The cavity was designed in a typical MODP (mesial-occlusal-distal-palatal) restoration failure shape when the palatal cusp has been lost. Two ceramic restorations [without coverage (WOC) and with (WC) buccal cuspal coverage with 2.0 mm reduction in cuspal height] were prepared to perform the fracture and fatigue tests with normal (200 N) and high (600 N) occlusal forces. The load versus AE signals in the fracture and fatigue tests were recorded to evaluate the restored tooth failure resistance. The results showed that non-significant differences in load value in the fracture test and the accumulated number of AE signals under normal occlusal force (200 N) in the fatigue test were found between with and without buccal cuspal coverage restorations. The first AE activity occurring for the WOC restoration was lower than that for the WC restoration in the fracture test. The number of AE signals increased with the cyclic load number. The accumulated number of AE signals for the WOC restoration was 187, higher than that (85) for the WC restoration under 600 N in the fatigue test. The AE technique and fatigue tests employed in this study were used as an assessment tool to evaluate the resistances in large CAD/CAM ceramic restorations. Non-significant differences in the tested fracture loads and accumulated number of AE signals under normal occlusal force (200 N) between different restorations indicated that aggressive treatment (with coverage preparation) in palatal cusp-replacing ceramic premolars require more attention for preserving and protecting the remaining tooth.
McLaskey, Gregory C.; Lockner, David A.
2016-01-01
Acoustic emission (AE) analyses have been used for decades for rock mechanics testing, but because AE systems are not typically calibrated, the absolute sizes of dynamic microcrack growth and other physical processes responsible for the generation of AEs are poorly constrained. We describe a calibration technique for the AE recording system as a whole (transducers + amplifiers + digitizers + sample + loading frame) that uses the impact of a 4.76-mm free-falling steel ball bearing as a reference source. We demonstrate the technique on a 76-mm diameter cylinder of westerly granite loaded in a triaxial deformation apparatus at 40 MPa confining pressure. The ball bearing is dropped inside a cavity within the sample while inside the pressure vessel. We compare this reference source to conventional AEs generated during loading of a saw-cut fault in a second granite sample. All located AEs occur on the saw-cut surface and have moment magnitudes ranging from M −5.7 down to at least M −8. Dynamic events rupturing the entire simulated fault surface (stick–slip events) have measurable stress drop and macroscopic slip and radiate seismic waves similar to those from a M −3.5 earthquake. The largest AE events that do not rupture the entire fault are M −5.7. For these events, we also estimate the corner frequency (200–300 kHz), and we assume the Brune model to estimate source dimensions of 4–6 mm. These AE sources are larger than the 0.2 mm grain size and smaller than the 76 × 152 mm fault surface.
Khogli, Ahmed Eltigani; Cauwels, Rita; Vercruysse, Chris; Verbeeck, Ronald; Martens, Luc
2013-01-01
Optimal pit and fissure sealing is determined by surface preparation techniques and choice of materials. This study aimed (i) to compare the microleakage and penetration depth of a hydrophilic sealant and a conventional resin-based sealant using one of the following preparation techniques: acid etching (AE) only, a diamond bur + AE, and Er:YAG laser combined with AE, and (ii) to evaluate the microleakage and penetration depth of the hydrophilic pit and fissure sealant on different surface conditions. Eighty recently extracted 3rd molars were randomly assigned to eight groups of ten teeth according to the material, preparation technique, and surface condition. For saliva contamination, 0.1 mL of fresh whole human saliva was used. All samples were submitted to 1000 thermal cycles and immersed in 2% methylene blue dye for 4 h. Sections were examined by a light microscope and analysed using image analysis software (Sigmascan(®)). The combination of Er:YAG + AE + conventional sealant showed the least microleakage. The sealing ability of the hydrophilic sealant was influenced by the surface condition. Er:YAG ablation significantly decreased the microleakage at the tooth-sealant interface compared to the non-invasive technique. The hydrophilic sealant applied on different surface conditions showed comparable result to the conventional resin-based sealant. © 2012 The Authors. International Journal of Paediatric Dentistry © 2012 BSPD, IAPD and Blackwell Publishing Ltd.
Probabilistic location estimation of acoustic emission sources in isotropic plates with one sensor
NASA Astrophysics Data System (ADS)
Ebrahimkhanlou, Arvin; Salamone, Salvatore
2017-04-01
This paper presents a probabilistic acoustic emission (AE) source localization algorithm for isotropic plate structures. The proposed algorithm requires only one sensor and uniformly monitors the entire area of such plates without any blind zones. In addition, it takes a probabilistic approach and quantifies localization uncertainties. The algorithm combines a modal acoustic emission (MAE) and a reflection-based technique to obtain information pertaining to the location of AE sources. To estimate confidence contours for the location of sources, uncertainties are quantified and propagated through the two techniques. The approach was validated using standard pencil lead break (PLB) tests on an Aluminum plate. The results demonstrate that the proposed source localization algorithm successfully estimates confidence contours for the location of AE sources.
Acoustic emissions diagnosis of rotor-stator rubs using the KS statistic
NASA Astrophysics Data System (ADS)
Hall, L. D.; Mba, D.
2004-07-01
Acoustic emission (AE) measurement at the bearings of rotating machinery has become a useful tool for diagnosing incipient fault conditions. In particular, AE can be used to detect unwanted intermittent or partial rubbing between a rotating central shaft and surrounding stationary components. This is a particular problem encountered in turbines used for power generation. For successful fault diagnosis, it is important to adopt AE signal analysis techniques capable of distinguishing between various types of rub mechanisms. It is also useful to develop techniques for inferring information such as the severity of rubbing or the type of seal material making contact on the shaft. It is proposed that modelling the cumulative distribution function of rub-induced AE signals with respect to appropriate theoretical distributions, and quantifying the goodness of fit with the Kolmogorov-Smirnov (KS) statistic, offers a suitable signal feature for diagnosis. This paper demonstrates the successful use of the KS feature for discriminating different classes of shaft-seal rubbing.
Advanced Exploration Systems Water Architecture Study Interim Results
NASA Technical Reports Server (NTRS)
Sargusingh, Miriam J.
2013-01-01
The mission of the Advanced Exploration System (AES) Water Recovery Project (WRP) is to develop advanced water recovery systems that enable NASA human exploration missions beyond low Earth orbit (LEO). The primary objective of the AES WRP is to develop water recovery technologies critical to near-term missions beyond LEO. The secondary objective is to continue to advance mid-readiness-level technologies to support future NASA missions. An effort is being undertaken to establish the architecture for the AES Water Recovery System (WRS) that meets both near- and long-term objectives. The resultant architecture will be used to guide future technical planning, establish a baseline development roadmap for technology infusion, and establish baseline assumptions for integrated ground and on-orbit Environmental Control and Life Support Systems definition. This study is being performed in three phases. Phase I established the scope of the study through definition of the mission requirements and constraints, as well as identifying all possible WRS configurations that meet the mission requirements. Phase II focused on the near-term space exploration objectives by establishing an International Space Station-derived reference schematic for long-duration (>180 day) in-space habitation. Phase III will focus on the long-term space exploration objectives, trading the viable WRS configurations identified in Phase I to identify the ideal exploration WRS. The results of Phases I and II are discussed in this paper.
Doyle, Lindsay; Mackay-Lyons, Marilyn
2013-03-01
Although aerobic exercise (AE) has been shown to improve aerobic capacity and reduce morbidity in neurological populations, its application is challenging. The purpose of this study was to survey Canadian physical therapists practicing in adult neurorehabilitation regarding the use of AE in clinical practice. Members of the Neurosciences Division of the Canadian Physiotherapy Association were invited to participate in a Web-based survey. Response rate was 36% (N = 155) with every Canadian province represented. The majority of respondents were females in full-time practice for more than 15 years. The majority (88%) agreed/strongly agreed with the following: "AE should be incorporated into treatment programs of patients with neurological conditions." Although 77% prescribed AE, barriers to use included patient concerns (cardiac status, cognitive/perceptual deficits, fatigue) and operations (lack of staff, time, screening tools). The most commonly used screening tools were health records and patient responses to exercise and the least common was exercise stress tests. Overground walking and cycle ergometry were the most frequently used AE modes, and general response to exercise and patient feedback were most frequently used for determining exercise intensity and monitoring AE. Respondents clearly recognized the importance of AE in neurorehabilitation. Barriers to application of AE and limitations in the use of appropriate screening and training procedures need to be addressed to advance clinical utilization of AE in neurological practice. Understanding current patterns of utilization of AE is important for the development of professional education initiatives and clinical guidelines for best practices in AE for neurological populations. Video Abstract available (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A40) for more insights from the authors.
Active Electrodes for Wearable EEG Acquisition: Review and Electronics Design Methodology.
Xu, Jiawei; Mitra, Srinjoy; Van Hoof, Chris; Yazicioglu, Refet Firat; Makinwa, Kofi A A
2017-01-01
Active electrodes (AEs), i.e., electrodes with built-in readout circuitry, are increasingly being implemented in wearable healthcare and lifestyle applications due to AEs' robustness to environmental interference. An AE locally amplifies and buffers μV-level EEG signals before driving any cabling. The low output impedance of an AE mitigates cable motion artifacts, thus enabling the use of high-impedance dry electrodes for greater user comfort. However, developing a wearable EEG system, with medical grade signal quality on noise, electrode offset tolerance, common-mode rejection ratio, input impedance, and power dissipation, remains a challenging task. This paper reviews state-of-the-art bio-amplifier architectures and low-power analog circuits design techniques intended for wearable EEG acquisition, with a special focus on an AE system interfaced with dry electrodes.
NASA Astrophysics Data System (ADS)
Falls, Stephen D.; Young, R. Paul
1998-04-01
Acoustic emission (AE) and ultrasonic-velocity monitoring studies have been undertaken at both the Atomic Energy of Canada Limited (AECL) Underground Research Laboratory (URL) and at the Swedish Nuclear Fuel Waste Management Company (SKB) Hard Rock Laboratory (HRL). At both locations the excavations were tunnels in granitic material at approximately 420 m depth. However, the stress regime was more severe at the URL Mine-by tunnel site than the HRL ZEDEX tunnel. Different parts of the ZEDEX tunnel were created using different excavation techniques. Using AE and ultrasonic techniques to study these tunnels we have been able to examine the nature of the excavation-disturbed zone around the tunnel, as well as examining the effects of different stress regimes and excavation techniques. Studies were undertaken both during and after the Mine-by tunnel excavation and during excavation in the ZEDEX tunnel. AE monitoring in the wall of the Mine-by tunnel during excavation showed that some activity occurred in the sidewall regions, but the spatial density of AE hypocentres increased toward the regions in the floor and roof of the tunnel where breakout notches formed. This sidewall activity was clustered primarily within 0.5 m of the tunnel wall. AE monitoring in the floor of the tunnel showed that small numbers of AE continued to occur in the notch region in the floor of the tunnel over 2 years after excavation was completed. This activity became more acute as the rock was heated, imposing thermally induced stresses on the volume. Ultrasonic-velocity studies both in the floor and the wall of the tunnel showed that the velocity is strongly anisotropic with the direction of slowest velocity orthogonal to the tunnel surface. The velocity increased with distance into the rock from the tunnel surface. In the floor, this effect was seen up to 2 m from the tunnel surface. Most of the change occurred within the first 0.5 m from the tunnel perimeter. At the lower-stress HRL, most of the AE again occur very close to the tunnel surface. The occurrence of AE under relatively low stress conditions suggests that the regions experiencing AE activity were damaged during the excavation process, thereby reducing their strength. The section of tunnel excavated by a tunnel-boring machine had fewer events, clustered much closer to the tunnel surface, than the sections excavated using drill and blast excavation techniques. P-wave velocity changes of only about 0.1% were experienced due to the tunnel excavation for ray paths within zero to 2 m from the tunnel surface indicating that crack damage was relatively low.
Wang, Yizhuo; Gou, Qing; Xu, Rongde; Chen, Xiaoming; Zhou, Zejian
2018-01-01
To compare the efficacy and safety profiles of sorafenib and apatinib in patients with intermediate- and advanced-stage hepatocellular carcinoma (HCC). This was a single-center, retrospective study where we collected the clinical data of 72 patients, diagnosed with intermediate or advanced HCC from January 2014 to December 2016. Depending on the treatment received, 38 patients were categorized into group S (sorafenib group) and 34 into group A (apatinib group). The patients in group A received the initial recommended dose of 750 mg once daily (QD), which was reduced to 250 mg QD in the case of any class 3 or 4 adverse event (AE). Sorafenib was administered orally 400 mg twice daily (BID), and dose was modified to 400 mg or 200 mg QD in the case of grade 3 or 4 AEs. The median overall survival (OS), progression-free survival (PFS), and AEs reported in the two groups were analyzed and compared. Among the 38 patients treated with sorafenib, one patient had complete response (CR), 5 patients had partial response (PR), and 10 patients had stable disease (SD), and among the 34 patients treated with apatinib, 6 patients had PR and 7 patients had SD with no cases of CR. PFS in group S was significantly longer compared with that in group A (7.39 vs 4.79 months, respectively, P =0.031). Similar observations were made for median OS (10.4 months in group S vs 7.18 months in group A, P =0.011). However, there was no significant difference in the objective response rates (ORRs) among the study population (15.7 vs 17.6%, P =0.829). Common AEs in group S included hand and foot syndrome (HFS) and diarrhea, whereas common AEs in group A included hypertension, proteinuria, and increased transaminase. Our study showed promising clinical outcome with apatinib, but the sorafenib group exhibited better clinical efficacy with no significant difference in safety profile.
The Divergence, Actions, Roles, and Relatives of Sodium-Coupled Bicarbonate Transporters
Boron, Walter F.
2013-01-01
The mammalian Slc4 (Solute carrier 4) family of transporters is a functionally diverse group of 10 multi-spanning membrane proteins that includes three Cl-HCO3 exchangers (AE1–3), five Na+-coupled HCO3− transporters (NCBTs), and two other unusual members (AE4, BTR1). In this review, we mainly focus on the five mammalian NCBTs-NBCe1, NBCe2, NBCn1, NDCBE, and NBCn2. Each plays a specialized role in maintaining intracellular pH and, by contributing to the movement of HCO3− across epithelia, in maintaining whole-body pH and otherwise contributing to epithelial transport. Disruptions involving NCBT genes are linked to blindness, deafness, proximal renal tubular acidosis, mental retardation, and epilepsy. We also review AE1–3, AE4, and BTR1, addressing their relevance to the study of NCBTs. This review draws together recent advances in our understanding of the phylogenetic origins and physiological relevance of NCBTs and their progenitors. Underlying these advances is progress in such diverse disciplines as physiology, molecular biology, genetics, immunocytochemistry, proteomics, and structural biology. This review highlights the key similarities and differences between individual NCBTs and the genes that encode them and also clarifies the sometimes confusing NCBT nomenclature. PMID:23589833
DOT National Transportation Integrated Search
2008-09-01
Three reports were produced from research sponsored by the Oregon Department of Transportation on acoustic emission (AE). The first describes the evaluation of AE techniques applied to two reinforced concrete (RC) bridge girders, which were loaded to...
Leak Detection by Acoustic Emission Monitoring. Phase 1. Feasibility Study
1994-05-26
various signal processing and noise descrimInation techniques during the Data Processing task. C. TEST DESCRIPTION 1. Laboratory Tests Following normal...success in applying these methods to descriminating between the AE bursts generated by two close AE sources In a section of an aircraft structure
S-Boxes Based on Affine Mapping and Orbit of Power Function
NASA Astrophysics Data System (ADS)
Khan, Mubashar; Azam, Naveed Ahmed
2015-06-01
The demand of data security against computational attacks such as algebraic, differential, linear and interpolation attacks has been increased as a result of rapid advancement in the field of computation. It is, therefore, necessary to develop such cryptosystems which can resist current cryptanalysis and more computational attacks in future. In this paper, we present a multiple S-boxes scheme based on affine mapping and orbit of the power function used in Advanced Encryption Standard (AES). The proposed technique results in 256 different S-boxes named as orbital S-boxes. Rigorous tests and comparisons are performed to analyse the cryptographic strength of each of the orbital S-boxes. Furthermore, gray scale images are encrypted by using multiple orbital S-boxes. Results and simulations show that the encryption strength of the orbital S-boxes against computational attacks is better than that of the existing S-boxes.
A wireless data acquisition system for acoustic emission testing
NASA Astrophysics Data System (ADS)
Zimmerman, A. T.; Lynch, J. P.
2013-01-01
As structural health monitoring (SHM) systems have seen increased demand due to lower costs and greater capabilities, wireless technologies have emerged that enable the dense distribution of transducers and the distributed processing of sensor data. In parallel, ultrasonic techniques such as acoustic emission (AE) testing have become increasingly popular in the non-destructive evaluation of materials and structures. These techniques, which involve the analysis of frequency content between 1 kHz and 1 MHz, have proven effective in detecting the onset of cracking and other early-stage failure in active structures such as airplanes in flight. However, these techniques typically involve the use of expensive and bulky monitoring equipment capable of accurately sensing AE signals at sampling rates greater than 1 million samples per second. In this paper, a wireless data acquisition system is presented that is capable of collecting, storing, and processing AE data at rates of up to 20 MHz. Processed results can then be wirelessly transmitted in real-time, creating a system that enables the use of ultrasonic techniques in large-scale SHM systems.
Chou, Victoria B; Omer, Saad B; Hussain, Hamidah; Mugasha, Christine; Musisi, Maria; Mmiro, Francis; Musoke, Philippa; Jackson, J Brooks; Guay, Laura A
2007-12-01
To determine costs for adverse event (AE) procedures for a large HIV perinatal trial by analyzing actual resource consumption using activity-based costing (ABC) in an international research setting. The AE system for an ongoing clinical trial in Uganda was evaluated using ABC techniques to determine costs from the perspective of the study. Resources were organized into cost categories (eg, personnel, patient care expenses, laboratory testing, equipment). Cost drivers were quantified, and unit cost per AE was calculated. A subset of time and motion studies was performed prospectively to observe clinic personnel time required for AE identification. In 18 months, there were 9028 AEs, with 970 (11%) reported as serious adverse events. Unit cost per AE was $101.97. Overall, AE-related costs represented 32% ($920,581 of $2,834,692) of all study expenses. Personnel ($79.30) and patient care ($11.96) contributed the greatest proportion of component costs. Reported AEs were predominantly nonserious (mild or moderate severity) and unrelated to study drug(s) delivery. Intensive identification and management of AEs to conduct clinical trials ethically and protect human subjects require expenditure of substantial human and financial resources. Better understanding of these resource requirements should improve planning and funding of international HIV-related clinical trials.
Aguiar, João P; Cardoso Borges, Fábio; Murteira, Rodrigo; Ramos, Catarina; Gouveia, Emanuel; Passos, Maria José; Miranda, Ana; da Costa, Filipa Alves
2018-06-02
Background Toxicity of oncology treatments in real-life patients is frequently disregarded and hence underreported. Objective To characterize adverse events (AEs) of immunotherapy and targeted therapy reported in patients with locally advanced or metastatic melanoma. Setting District Hospital for Cancer treatment (Instituto Português de Oncologia de Lisboa Francisco Gentil). Method A retrospective cohort of melanoma patients was established, comprising adult patients diagnosed with malignant melanoma treated with immunotherapy or targeted therapy. Exposure was characterized by nature, time and intensity of exposure. To account for different exposure periods, person-time was used as unit of analysis. Main outcomes measure Occurrence of AEs. Results Data from 111 patients included in the cohort indicates the majority received immunotherapy regimens (CTLA-4, anti-PD-1 and combination therapy; (n = 70; 63.1%), among which anti-PD-1 were the predominant treatment. Pembrolizumab was the most frequently prescribed drug (n = 30; 45.7%). Three hundred and seventy-one AEs were extracted. The incidence of AEs was lower in the anti-PD-1 mAc group (54 AEs per 1000 person.months) and the number of AEs/patient was also lower (3.1 ± 2.0). Grade 3 to 4 AEs occurred in 15.3% (n = 17) of the cohort, being more common in the targeted therapy group. Forty-two (11.6%) of the extracted AEs were not described in the Summary of Product Characteristics of the drugs under study. Conclusion This study suggests various known and unknown AEs of immunotherapy and targeted therapy may be identified using the Cancer Registry database. These events should be considered as signals worth further investigation for assessment of causality as the underreporting of AEs in cancer may have potential implications for the patient's quality of life.
Marcela, P; Hassan, A Abu; Hamdan, A; Dieng, H; Kumara, T K
2015-12-01
Mating behavior between Aedes aegypti and Ae. albopictus, established colony strains were examined under laboratory conditions (30-cm(3) screened cages) for 5 consecutive days. The effect of selected male densities (30, 20, 10) and female density (20) on the number of swarming, mating pairs, eggs produced, and inseminated females were evaluated. Male densities significantly increased swarming behavior, mating pairs, and egg production of heterospecific females, but female insemination was reduced. Aedes aegypti males mate more readily with heterospecific females than do Ae. albopictus males. The current study suggests that Ae. aegypti males were not species-specific in mating, and if released into the field as practiced in genetically modified mosquito techniques, they may mate with both Ae. aegypti and Ae. albopictus females, hence reducing populations of both species by producing infertile eggs.
Changes in the respiratory microbiome during acute exacerbations of idiopathic pulmonary fibrosis.
Molyneaux, Philip L; Cox, Michael J; Wells, Athol U; Kim, Ho Cheol; Ji, Wonjun; Cookson, William O C; Moffatt, Miriam F; Kim, Dong Soon; Maher, Toby M
2017-02-01
Acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) have been defined as events of clinically significant respiratory deterioration with an unidentifiable cause. They carry a significant mortality and morbidity and while their exact pathogenesis remains unclear, the possibility remains that hidden infection may play a role. The aim of this pilot study was to determine whether changes in the respiratory microbiota occur during an AE-IPF. Bacterial DNA was extracted from bronchoalveolar lavage from patients with stable IPF and those experiencing an AE-IPF. A hyper-variable region of the 16S ribosomal RNA gene (16S rRNA) was amplified, quantified and pyrosequenced. Culture independent techniques demonstrate AE-IPF is associated with an increased BAL bacterial burden compared to stable disease and highlight shifts in the composition of the respiratory microbiota during an AE-IPF.
Identification of adverse events in ground transport emergency medical services.
Patterson, P Daniel; Weaver, Matthew D; Abebe, Kaleab; Martin-Gill, Chris; Roth, Ronald N; Suyama, Joseph; Guyette, Francis X; Rittenberger, Jon C; Krackhardt, David; Arnold, Robert; Yealy, Donald M; Lave, Judith
2012-01-01
The purpose of this study was to develop a method to define and rate the severity of adverse events (AEs) in emergency medical services (EMS) safety research. They used a modified Delphi technique to develop a consensus definition of an AE. The consensus definition was as follows: "An adverse event in EMS is a harmful or potentially harmful event occurring during the continuum of EMS care that is potentially preventable and thus independent of the progression of the patient's condition." Physicians reviewed 250 charts from 3 EMS agencies for AEs. The authors examined physician agreement using κ, Fleiss's κ, and corresponding 95% confidence intervals (CIs). Overall physician agreement on presence of an AE per chart was fair (κ = 0.24; 95% CI = 0.19, 0.29). These findings should serve as a basis for refining and implementing an AE evaluation instrument.
Schmitt, Jochen; Spuls, Phyllis I; Thomas, Kim S; Simpson, Eric; Furue, Masutaka; Deckert, Stefanie; Dohil, Magdalene; Apfelbacher, Christian; Singh, Jasvinder A; Chalmers, Joanne; Williams, Hywel C
2014-10-01
The lack of core outcome sets for atopic eczema (AE) is a major obstacle for advancing evidence-based treatment. The global Harmonising Outcome Measures for Eczema (HOME) initiative has already defined clinical signs, symptoms, quality of life, and long-term control of flares as core outcome domains for AE trials. This article deals with the standardization of measurement instruments to assess clinical signs of AE. To resolve the current lack of standardization of the assessment of clinical signs of AE, we followed a structured process of systematic reviews and international consensus sessions to identify 1 core outcome measurement instrument for assessment of clinical signs in all future AE trials. Systematic reviews indicated that from 16 different instruments identified to assess clinical signs of AE, only the Eczema Area and Severity Index (EASI) and the objective Scoring Atopic Dermatitis (SCORAD) index were identified as extensively validated. The EASI has adequate validity, responsiveness, internal consistency, and intraobserver reliability. The objective SCORAD index has adequate validity, responsiveness, and interobserver reliability but unclear intraobserver reliability to measure clinical signs of AE. In an international consensus study, patients, physicians, nurses, methodologists, and pharmaceutical industry representatives agreed that the EASI is the preferred core instrument to measure clinical signs in all future AE trials. All stakeholders involved in designing, reporting, and using clinical trials on AE are asked to comply with this consensus to enable better evidence-based decision making, clearer scientific communication, and improved patient care. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Expression and role of anion exchanger 1 in esophageal squamous cell carcinoma.
Shiozaki, Atsushi; Kudou, Michihiro; Ichikawa, Daisuke; Shimizu, Hiroki; Arita, Tomohiro; Kosuga, Toshiyuki; Konishi, Hirotaka; Komatsu, Shuhei; Fujiwara, Hitoshi; Okamoto, Kazuma; Kishimoto, Mitsuo; Marunaka, Yoshinori; Otsuji, Eigo
2017-03-14
Recent studies have described important roles for the anion exchanger (AE) in epithelial carcinogenesis and tumor behavior. The objectives of the present study were to investigate the role of AE1 in the regulation of genes involved in tumor progression and the clinicopathological significance of its expression in esophageal squamous cell carcinoma (ESCC). An immunohistochemical analysis was performed on 61 primary tumor samples obtained from ESCC patients who underwent esophagectomy. AE1 was primarily located in the cell membranes or cytoplasm of carcinoma cells, and its distribution pattern was related to the histological degree of the differentiation of SCC or the pT category. Among patients with pT2-3 ESCC, the 5-year survival rate of patients with diffuse AE1 expression (40.2%) was significantly lower than that of patients with focal expression (74.0%). AE1 was strongly expressed in KYSE150 and TE8 human ESCC cells. The depletion of AE1 using siRNA inhibited cell proliferation, migration, and invasion and induced apoptosis. The results of the microarray analysis revealed that MAPK and Hedgehog signaling pathway-related genes, such as DHH, and GLI1, were down-regulated in AE1-depleted KYSE150 cells. In conclusions, the results of the present study suggest that the diffuse expression of AE1 is related to a worse prognosis in patients with advanced ESCC, and that it regulates tumor progression by affecting MAPK and Hedgehog signaling pathways. These results provide an insight into the role of AE1 as a mediator of and/or a biomarker for ESCC.
Kondalsamy-Chennakesavan, Srinivas; Bouman, Chantal; De Jong, Suzanne; Sanday, Karen; Nicklin, Jim; Land, Russell; Obermair, Andreas
2009-12-01
Advanced gynecological surgery undertaken in a specialized gynecologic oncology unit may be associated with significant perioperative morbidity. Validated risk prediction models are available for general surgical specialties but currently not for gynecological cancer surgery. The objective of this study was to evaluate risk factors for adverse events (AEs) of patients treated for suspected or proven gynecological cancer and to develop a clinical risk score (RS) to predict such AEs. AEs were prospectively recorded and matched with demographical, clinical and histopathological data on 369 patients who had an abdominal or laparoscopic procedure for proven or suspected gynecological cancer at a tertiary gynecological cancer center. Stepwise multiple logistic regression was used to determine the best predictors of AEs. For the risk score (RS), the coefficients from the model were scaled using a factor of 2 and rounded to the nearest integer to derive the risk points. Sum of all the risk points form the RS. Ninety-five patients (25.8%) had at least one AE. Twenty-nine (7.9%) and 77 (20.9%) patients experienced intra- and postoperative AEs respectively with 11 patients (3.0%) experiencing both. The independent predictors for any AE were complexity of the surgical procedure, elevated SGOT (serum glutamic oxaloacetic transaminase, > or /=35 U/L), higher ASA scores and overweight. The risk score can vary from 0 to 14. The risk for developing any AE is described by the formula 100 / (1 + e((3.697 - (RS /2)))). RS allows for quantification of the risk for AEs. Risk factors are generally not modifiable with the possible exception of obesity.
Acoustic emission and nondestructive evaluation of biomaterials and tissues.
Kohn, D H
1995-01-01
Acoustic emission (AE) is an acoustic wave generated by the release of energy from localized sources in a material subjected to an externally applied stimulus. This technique may be used nondestructively to analyze tissues, materials, and biomaterial/tissue interfaces. Applications of AE include use as an early warning tool for detecting tissue and material defects and incipient failure, monitoring damage progression, predicting failure, characterizing failure mechanisms, and serving as a tool to aid in understanding material properties and structure-function relations. All these applications may be performed in real time. This review discusses general principles of AE monitoring and the use of the technique in 3 areas of importance to biomedical engineering: (1) analysis of biomaterials, (2) analysis of tissues, and (3) analysis of tissue/biomaterial interfaces. Focus in these areas is on detection sensitivity, methods of signal analysis in both the time and frequency domains, the relationship between acoustic signals and microstructural phenomena, and the uses of the technique in establishing a relationship between signals and failure mechanisms.
Acoustic emission source localization based on distance domain signal representation
NASA Astrophysics Data System (ADS)
Gawronski, M.; Grabowski, K.; Russek, P.; Staszewski, W. J.; Uhl, T.; Packo, P.
2016-04-01
Acoustic emission is a vital non-destructive testing technique and is widely used in industry for damage detection, localisation and characterization. The latter two aspects are particularly challenging, as AE data are typically noisy. What is more, elastic waves generated by an AE event, propagate through a structural path and are significantly distorted. This effect is particularly prominent for thin elastic plates. In these media the dispersion phenomenon results in severe localisation and characterization issues. Traditional Time Difference of Arrival methods for localisation techniques typically fail when signals are highly dispersive. Hence, algorithms capable of dispersion compensation are sought. This paper presents a method based on the Time - Distance Domain Transform for an accurate AE event localisation. The source localisation is found through a minimization problem. The proposed technique focuses on transforming the time signal to the distance domain response, which would be recorded at the source. Only, basic elastic material properties and plate thickness are used in the approach, avoiding arbitrary parameters tuning.
Insulin pump-associated adverse events in children and adolescents--a prospective study.
Wheeler, Benjamin J; Heels, Kristine; Donaghue, Kim C; Reith, David M; Ambler, Geoffrey R
2014-09-01
Intensive insulin regimens are now the mainstay of modern, type 1 diabetes mellitus management. Insulin pumps (CSII) are a key technique used. Although there has been considerable study of outcomes, there are few recent data on CSII-associated adverse events (AEs) and their incidence and characteristics. Phone calls to our 24-h diabetes support service were screened for CSII-associated AEs. Phone interviews were conducted with the parent/patient, within 96 h of the event. Interviews explored AE characteristics and the role of the user, as well as questions relating to outcome and the impact to the family and patient. Comparisons were made with clinic CSII patients not reporting an AE. Over a 16-week study period, 50 confirmed AEs occurred in 45 of 405 (11.1%) patients. This was annualized to an AE incidence of 40 AEs/100 person-years. Pump malfunction and infusion set/site failures were the most common events reported, occurring in 27 (54.0%) and 18 (36.0%) AEs, respectively. A user- or education-related issue was implicated in 22 (44.0%) events. Pump replacement occurred in 19 of 50 occurrences (38.0%). Additionally, 16 (32.0%) reported a hospital admission or emergency department attendance as a consequence. When compared with those on CSII not reporting an AE, AEs were associated with age <10 years (odds ratio=3.2 [95% confidence interval, 1.7-6.1]) but not with gender, glycosylated hemoglobin, diabetes duration, or pumping duration. This is the first prospective study to look at AEs in modern-generation insulin pumps. AEs appear common and should be anticipated. Their origin is multifactorial, with the pump, associated consumables, and the user all being important factors. Ongoing support and anticipatory education are essential to minimize pump-associated AEs and their impact.
New Secure E-mail System Based on Bio-Chaos Key Generation and Modified AES Algorithm
NASA Astrophysics Data System (ADS)
Hoomod, Haider K.; Radi, A. M.
2018-05-01
The E-mail messages exchanged between sender’s Mailbox and recipient’s Mailbox over the open systems and insecure Networks. These messages may be vulnerable to eavesdropping and itself poses a real threat to the privacy and data integrity from unauthorized persons. The E-mail Security includes the following properties (Confidentiality, Authentication, Message integrity). We need a safe encryption algorithm to encrypt Email messages such as the algorithm Advanced Encryption Standard (AES) or Data Encryption Standard DES, as well as biometric recognition and chaotic system. The proposed E-mail system security uses modified AES algorithm and uses secret key-bio-chaos that consist of biometric (Fingerprint) and chaotic system (Lu and Lorenz). This modification makes the proposed system more sensitive and random. The execution time for both encryption and decryption of the proposed system is much less from original AES, in addition to being compatible with all Mail Servers.
Low-Level Space Optimization of an AES Implementation for a Bit-Serial Fully Pipelined Architecture
NASA Astrophysics Data System (ADS)
Weber, Raphael; Rettberg, Achim
A previously developed AES (Advanced Encryption Standard) implementation is optimized and described in this paper. The special architecture for which this implementation is targeted comprises synchronous and systematic bit-serial processing without a central controlling instance. In order to shrink the design in terms of logic utilization we deeply analyzed the architecture and the AES implementation to identify the most costly logic elements. We propose to merge certain parts of the logic to achieve better area efficiency. The approach was integrated into an existing synthesis tool which we used to produce synthesizable VHDL code. For testing purposes, we simulated the generated VHDL code and ran tests on an FPGA board.
NASA Astrophysics Data System (ADS)
Holford, Karen M.; Eaton, Mark J.; Hensman, James J.; Pullin, Rhys; Evans, Sam L.; Dervilis, Nikolaos; Worden, Keith
2017-04-01
The acoustic emission (AE) phenomenon has many attributes that make it desirable as a structural health monitoring or non-destructive testing technique, including the capability to continuously and globally monitor large structures using a sparse sensor array and with no dependency on defect size. However, AE monitoring is yet to fulfil its true potential, due mainly to limitations in location accuracy and signal characterisation that often arise in complex structures with high levels of background noise. Furthermore, the technique has been criticised for a lack of quantitative results and the large amount of operator interpretation required during data analysis. This paper begins by introducing the challenges faced in developing an AE based structural health monitoring system and then gives a review of previous progress made in addresing these challenges. Subsequently an overview of a novel methodology for automatic detection of fatigue fractures in complex geometries and noisy environments is presented, which combines a number of signal processing techniques to address the current limitations of AE monitoring. The technique was developed for monitoring metallic landing gear components during pre-flight certification testing and results are presented from a full-scale steel landing gear component undergoing fatigue loading. Fracture onset was successfully identify automatically at 49,000 fatigue cycles prior to final failure (validated by the use of dye penetrant inspection) and the fracture position was located to within 10 mm of the actual location.
Study of a water quality imager for coastal zone missions
NASA Technical Reports Server (NTRS)
Staylor, W. F.; Harrison, E. F.; Wessel, V. W.
1975-01-01
The present work surveys water quality user requirements and then determines the general characteristics of an orbiting imager (the Applications Explorer, or AE) dedicated to the measurement of water quality, which could be used as a low-cost means of testing advanced imager concepts and assessing the ability of imager techniques to meet the goals of a comprehensive water quality monitoring program. The proposed imager has four spectral bands, a spatial resolution of 25 meters, and swath width of 36 km with a pointing capability of 330 km. Silicon photodetector arrays, pointing systems, and several optical features are included. A nominal orbit of 500 km altitude at an inclination of 50 deg is recommended.
Zhang, Wenxiong; Wei, Yiping; Yu, Dongliang; Xu, Jianjun; Peng, Jinhua
2018-04-01
The epidermal growth factor receptor tyrosine kinase inhibitors gefitinib and erlotinib are effective for advanced non-small cell lung cancer (NSCLC). This meta-analysis compared their effectiveness and safety. We searched systematically in PubMed, ScienceDirect, The Cochrane Library, Scopus, Ovid MEDLINE, EMBASE, Web of Science, and Google Scholar for relevant clinical trials regarding gefitinib versus erlotinib for NSCLC. Antitumor effectiveness (overall survival [OS], progression-free survival [PFS], objective response rate [ORR] and disease control rate [DCR]) and adverse effects [AEs]) were assessed. Forty studies comprising 9376 participants were included. The results suggested that gefitinib and erlotinib are effective for advanced NSCLC with comparable PFS (95% confidence intervals [CI]: 0.98-1.11, P = .15), OS (95% CI: 0.93-1.19, P = .45), ORR (95% CI: 0.99-1.16, P = .07), and DCR (95% CI: 0.92-1.03, P = .35). For erlotinib, dose reduction was significantly more frequent (95% CI: 0.10-0.57, P = .001) as were grade 3 to 5 AEs (95% CI: 0.36-0.79, P = .002). In the subgroup analysis, the erlotinib group had a significant higher rate and severity of skin rash, nausea/vomiting, fatigue, and stomatitis. Gefitinib was proven to be the better choice for advanced NSCLC, with equal antitumor effectiveness and fewer AEs compared with erlotinib. Further large-scale, well-designed randomized controlled trials are warranted to confirm our validation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schefter, Tracey E., E-mail: tracey.schefter@ucdenver.edu; Winter, Kathryn; Kwon, Janice S.
Purpose: Concurrent cisplatin-based chemoradiotherapy (CRT) is the standard treatment for locally advanced cervical cancer. RTOG 0417 was a Phase II study exploring the safety and efficacy of the addition of bevacizumab to standard CRT. Methods and Materials: Eligible patients with bulky tumors (Stage IB-IIIB) were treated with once-weekly cisplatin (40 mg/m{sup 2}) chemotherapy and standard pelvic radiotherapy and brachytherapy. Bevacizumab was administered at 10 mg/kg intravenously every 2 weeks for three cycles. Treatment-related serious adverse event (SAE) and other adverse event (AE) rates within the first 90 days from treatment start were determined. Treatment-related SAEs were defined as any Grademore » {>=}4 vaginal bleeding or thrombotic event or Grade {>=}3 arterial event, gastrointestinal (GI) bleeding, or bowel/bladder perforation, or any Grade 5 treatment-related death. Treatment-related AEs included all SAEs and Grade 3 or 4 GI toxicity persisting for >2 weeks despite medical intervention, Grade 4 neutropenia or leukopenia persisting for >7 days, febrile neutropenia, Grade 3 or 4 other hematologic toxicity, and Grade 3 or 4 GI, renal, cardiac, pulmonary, hepatic, or neurologic AEs. All AEs were scored using the National Cancer Institute Common Terminology Criteria (CTCAE) v 3.0 (MedDRA version 6.0). Results: A total of 60 patients from 28 institutions were enrolled between 2006 and 2009, and of these, 49 patients were evaluable. The median follow-up was 12.4 months (range, 4.6-31.4 months).The median age was 45 years (range, 22-80 years). Most patients had FIGO Stage IIB (63%) and were of Zubrod performance status of 0 (67%). 80% of cases were squamous. There were no treatment-related SAEs. There were 15 (31%) protocol-specified treatment-related AEs within 90 days of treatment start; the most common were hematologic (12/15; 80%). 18 (37%) occurred during treatment or follow-up at any time. 37 of the 49 patients (76%) had cisplatin and bevacizumab administered per protocol, and 46 of the 49 (94%) had both external beam and brachytherapy administered per protocol or with acceptable variation. Conclusion: Bevacizumab in addition to standard pelvic chemoradiotherapy for locally advanced cervical cancer is feasible and safe with respect to the protocol-specified treatment-related SAEs and AEs.« less
Thermal protection system (TPS) monitoring using acoustic emission
NASA Astrophysics Data System (ADS)
Hurley, D. A.; Huston, D. R.; Fletcher, D. G.; Owens, W. P.
2011-04-01
This project investigates acoustic emission (AE) as a tool for monitoring the degradation of thermal protection systems (TPS). The AE sensors are part of an array of instrumentation on an inductively coupled plasma (ICP) torch designed for testing advanced thermal protection aerospace materials used for hypervelocity vehicles. AE are generated by stresses within the material, propagate as elastic stress waves, and can be detected with sensitive instrumentation. Graphite (POCO DFP-2) is used to study gas-surface interaction during degradation of thermal protection materials. The plasma is produced by a RF magnetic field driven by a 30kW power supply at 3.5 MHz, which creates a noisy environment with large spikes when powered on or off. AE are waveguided from source to sensor by a liquid-cooled copper probe used to position the graphite sample in the plasma stream. Preliminary testing was used to set filters and thresholds on the AE detection system (Physical Acoustics PCI-2) to minimize the impact of considerable operating noise. Testing results show good correlation between AE data and testing environment, which dictates the physics and chemistry of the thermal breakdown of the sample. Current efforts for the project are expanding the dataset and developing statistical analysis tools. This study shows the potential of AE as a powerful tool for analysis of thermal protection material thermal degradations with the unique capability of real-time, in-situ monitoring.
Investigation of Hafnium oxide/Copper resistive memory for advanced encryption applications
NASA Astrophysics Data System (ADS)
Briggs, Benjamin D.
The Advanced Encryption Standard (AES) is a widely used encryption algorithm to protect data and communications in today's digital age. Modern AES CMOS implementations require large amounts of dedicated logic and must be tuned for either performance or power consumption. A high throughput, low power, and low die area AES implementation is required in the growing mobile sector. An emerging non-volatile memory device known as resistive memory (ReRAM) is a simple metal-insulator-metal capacitor device structure with the ability to switch between two stable resistance states. Currently, ReRAM is targeted as a non-volatile memory replacement technology to eventually replace flash. Its advantages over flash include ease of fabrication, speed, and lower power consumption. In addition to memory, ReRAM can also be used in advanced logic implementations given its purely resistive behavior. The combination of a new non-volatile memory element ReRAM along with high performance, low power CMOS opens new avenues for logic implementations. This dissertation will cover the design and process implementation of a ReRAM-CMOS hybrid circuit, built using IBM's 10LPe process, for the improvement of hardware AES implementations. Further the device characteristics of ReRAM, specifically the HfO2/Cu memory system, and mechanisms for operation are not fully correlated. Of particular interest to this work is the role of material properties such as the stoichiometry, crystallinity, and doping of the HfO2 layer and their effect on the switching characteristics of resistive memory. Material properties were varied by a combination of atomic layer deposition and reactive sputtering of the HfO2 layer. Several studies will be discussed on how the above mentioned material properties influence switching parameters, and change the underlying physics of device operation.
Wright, Jennifer A; Larson, Ryan T; Richardson, Alec G; Cote, Noel M; Stoops, Craig A; Clark, Marah; Obenauer, Peter J
2015-03-01
The BG-Sentinel® (BGS) trap and oviposition cups (OCs) have both proven effective in the surveillance of Aedes species. This study aimed to determine which of the 2 traps could best characterize the relative population sizes of Aedes albopictus and Aedes aegypti in an urban section of Jacksonville, FL. Until 1986, Ae. aegypti was considered the dominant container-breeding species in urban northeastern Florida. Since the introduction of Ae. albopictus, Ae. aegypti has become almost completely extirpated. In 2011, a resurgence of Ae. aegypti was detected in the urban areas of Jacksonville; thus this study initially set out to determine the extent of Ae. aegypti reintroduction to the area. We determined that the BGS captured a greater number of adult Ae. aegypti than Ae. albopictus, while OCs did not monitor significantly different numbers of either species, even in areas where the BGS traps suggested a predominance of one species over the other. Both traps were effective at detecting Aedes spp.; however, the BGS proved more diverse by detecting over 20 other species as well. Our results show that in order to accurately determine vectorborne disease threats and the impact of control operations on these 2 species, multiple trapping techniques should be utilized when studying Ae. aegypti and Ae. albopictus population dynamics.
Damping Rate Measurements of Medium n Alfv'en Eigenmodes in JET
NASA Astrophysics Data System (ADS)
Klein, Alexander; Testa, Duccio; Snipes, Joseph; Fasoli, Ambrogio; Carfantan, Hervé
2007-11-01
Alfv'en Eigenmodes (AE's) with mode numbers 5 < n < 20 are expected to be unstable in burning tokamaks and may lead to loss of fast particle confinement. The active MHD spectroscopy program at JET has already provided a wealth of information about low n (n <= 2) AE's in the past decade, but a recently installed array of four antennas is capable of driving higher mode numbered (n < 100, 30 < f < 350 kHz) perturbations. In the latest JET campaign, the damping rates for several types of AE's were measured parasitically in a wide range of tokamak scenarios. We review the active MHD diagnostic and present the first measurements of medium-n AE stability on JET, then describe future plans for the active MHD spectroscopy project. The data analysis involves a novel method for resolving multiple AE's that exist at identical frequencies, which uses techniques based on the SparSpec code.
Report on the Development of the Advanced Encryption Standard (AES).
Nechvatal, J; Barker, E; Bassham, L; Burr, W; Dworkin, M; Foti, J; Roback, E
2001-01-01
In 1997, the National Institute of Standards and Technology (NIST) initiated a process to select a symmetric-key encryption algorithm to be used to protect sensitive (unclassified) Federal information in furtherance of NIST's statutory responsibilities. In 1998, NIST announced the acceptance of 15 candidate algorithms and requested the assistance of the cryptographic research community in analyzing the candidates. This analysis included an initial examination of the security and efficiency characteristics for each algorithm. NIST reviewed the results of this preliminary research and selected MARS, RC™, Rijndael, Serpent and Twofish as finalists. Having reviewed further public analysis of the finalists, NIST has decided to propose Rijndael as the Advanced Encryption Standard (AES). The research results and rationale for this selection are documented in this report.
Acoustic emission analysis of tooth-composite interfacial debonding.
Cho, N Y; Ferracane, J L; Lee, I B
2013-01-01
This study detected tooth-composite interfacial debonding during composite restoration by means of acoustic emission (AE) analysis and investigated the effects of composite properties and adhesives on AE characteristics. The polymerization shrinkage, peak shrinkage rate, flexural modulus, and shrinkage stress of a methacrylate-based universal hybrid, a flowable, and a silorane-based composite were measured. Class I cavities on 49 extracted premolars were restored with 1 of the 3 composites and 1 of the following adhesives: 2 etch-and-rinse adhesives, 2 self-etch adhesives, and an adhesive for the silorane-based composite. AE analysis was done for 2,000 sec during light-curing. The silorane-based composite exhibited the lowest shrinkage (rate), the longest time to peak shrinkage rate, the lowest shrinkage stress, and the fewest AE events. AE events were detected immediately after the beginning of light-curing in most composite-adhesive combinations, but not until 40 sec after light-curing began for the silorane-based composite. AE events were concentrated at the initial stage of curing in self-etch adhesives compared with etch-and-rinse adhesives. Reducing the shrinkage (rate) of composites resulted in reduced shrinkage stress and less debonding, as evidenced by fewer AE events. AE is an effective technique for monitoring, in real time, the debonding kinetics at the tooth-composite interface.
An improved measurement of Vickers indentation behaviour through enhanced instrumentation
NASA Astrophysics Data System (ADS)
Faisal, N. H.; Reuben, R. L.; Ahmed, R.
2011-01-01
This work presents an enhanced instrumented Vickers indentation technique capable of recording force, displacement and acoustic emission (AE) during loading condition. Four materials were chosen for examination; copper, aluminium, steel and as-sprayed HVOF WC-12%Co coating. Results indicate that force-displacement (P-h) profiles are essentially bilinear with two characteristic slopes separated by a distinct displacement arrest for all loads above 98 N. The P-h curve indicates three distinct loading stages (I, II and III) and the stage III mechanical energy increases with loads. About 66% of the hardened steel indentations but only about 18% of the as-sprayed HVOF WC-12%Co coating indentations exhibited an AE record that could be separated into three distinct zones (A, B and C). Where zoning was possible the AE corresponding to a zone correlated well with the AE associated with a loading stage. It is concluded that plastic deformation in soft metals produced little AE, whereas brittle fracture in hardened steel and as-sprayed HVOF WC-12%Co coating produced significant AE. AE may or may not be focused onto particular stages of the indentation and a full measure of crack prevalence would require fractal dimension analysis, which is time consuming, offering a motivation for AE-based indentation testing.
Efficient SO2 capture by amine functionalized PEG.
Yang, Dezhong; Hou, Minqiang; Ning, Hui; Zhang, Jianling; Ma, Jun; Han, Buxing
2013-11-07
Polyethylene glycols (PEGs) are a class of non-toxic, non-volatile, biocompatible, and widely available polymers. In this work, we synthesized N-ethyl-N-(2-(2-(2-methoxyethoxy)ethoxy)ethyl)-2-aminoethanol (EE3AE) that combines the properties of PEG and amines, and N-decyl-N-ethyl-2-aminoethanol (DEAE). Their performances to capture SO2 were studied at different temperatures, pressures, and absorption times. The interaction between the absorbents and SO2 were characterized by NMR and FTIR techniques. It was demonstrated that both EE3AE and DEAE could absorb SO2 efficiently, and there existed chemical and physical interactions between the absorbents and SO2. In particular, the absorption capacity of EE3AE could be as high as 1.09 g SO2 per g EE3AE at 1 atm. The absorption capacity of EE3AE was much larger than that of DEAE because the ether group in the EE3AE interacted with SO2 more strongly than the alkyl group in the DEAE. The SO2 absorbed by EE3AE could be stripped out by bubbling N2 or by applying a vacuum and the EE3AE could be reused. Moreover, both absorbents exhibited a high SO2-CO2 selectivity.
Liu, Frank Xiaoqing; Witt, Edward A; Ebbinghaus, Scot; DiBonaventura Beyer, Grace; Basurto, Enrique; Joseph, Richard W
2017-10-25
Understanding the perceptions of patients and oncology nurses about the relative importance of benefits and risks associated with newer treatments of advanced melanoma can help to inform clinical decision-making. The aims of this study were to quantify and compare the views of patients and oncology nurses regarding the importance of attributes of treatments of advanced melanoma. A discrete choice experiment (DCE) was conducted in US-based oncology nurses and patients diagnosed with advanced melanoma. Patients and nurses were enlisted through online panels. In a series of scenarios, respondents had to choose between 2 hypothetical treatments, each with 7 attributes: mode of administration (MoA), dosing schedule (DS), median duration of therapy (DoT), objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and grade 3 or 4 adverse events (AEs). Hierarchical Bayesian logistic regression models were used to estimate preference weights. A total of 200 patients with advanced melanoma and 150 oncology nurses participated. The relative importance estimates of attributes by patients and nurses, respectively, were as follows: OS, 33% and 28%; AEs, 29% and 26%; ORR, 25% and 27%; PFS, 12% and 15%; DS, 2% and 3%; DoT, 0% and 0%; and MoA, 0% and 0%. Both patients and oncology nurses valued OS, ORR, and AEs as the most important treatment attributes for advanced melanoma, followed by PFS, whereas DS, DoT, and MoA were given less value in their treatment decisions. Oncology nurses and patients have similar views on important treatment considerations for advanced melanoma, which can help build trust in shared decision-making.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.
Zheng, Yan-Bo; Gong, Jian-Hua; Liu, Xiu-Jun; Li, Yi; Zhen, Yong-Su
2017-05-01
CD13 is a marker of angiogenic endothelial cells, and recently it is proved to be a biomarker of human liver cancer stem cells (CSCs). Herein, the therapeutic effects of NGR-LDP-AE, a fusion protein composed of CD13-targeting peptide NGR and antitumor antibiotic lidamycin, on human liver cancer and its mechanism were studied. Western blot and immunofluorescence assay demonstrated that CD13 (WM15 epitope) was expressed in both human liver cancer cell lines and vascular endothelial cells, while absent in normal liver cells. MTT assay showed that NGR-LDP-AE displayed potent cytotoxicity to cultured tumor cell lines with IC 50 values at low nanomolar level. NGR-LDP-AE inhibited tumorsphere formation of liver cancer cells, and the IC 50 values were much lower than that in MTT assay, indicating selectively killing of CSCs. In endothelial tube formation assay, NGR-LDP-AE at low cytotoxic dose significantly inhibited the formation of intact tube networks. Animal experiment demonstrated that NGR-LDP-AE inhibited the growth of human liver cancer xenograft. Immunohistochemical analysis showed that NGR-LDP-AE induced the down-regulation of CD13. In vitro experiment using cultured tumor cells also confirmed this result. NGR-LDP-AE activated both apoptotic and autophagic pathways in cultured tumor cells, while the induced autophagy protected cells from death. Conclusively, NGR-LDP-AE exerts its antitumor activity via killing liver CSCs and inhibiting angiogenesis. With one targeting motif, NGR-LDP-AE acts on both liver CSCs and angiogenic endothelial cells. It is a promising dual targeting fusion protein for liver cancer therapy, especially for advanced or relapsed cancers. © 2017 Wiley Periodicals, Inc.
2010-01-16
Advanced Exploration Systems (AES) Modular Power Systems for Space Exploration (AMPS); electrochemistry, AMPS, will infuse and demonstrate batteries, fuel cells, and other power modules for exploration ground system demonstrations
2010-01-16
Advanced Exploration Systems (AES) Modular Power Systems for Space Exploration (AMPS); electrochemistry, AMPS, will infuse and demonstrate batteries, fuel cells, and other power modules for exploration ground system demonstrations
2010-01-16
Advanced Exploration Systems (AES) Modular Power Systems for Space Exploration (AMPS); electrochemistry, AMPS, will infuse and demonstrate batteries, fuel cells, and other power modules for exploration ground system demonstrations
2010-01-16
Advanced Exploration Systems (AES) Modular Power Systems for Space Exploration (AMPS); electrochemistry, AMPS, will infuse and demonstrate batteries, fuel cells, and other power modules for exploration ground system demonstrations
Li, Dongsheng; Yang, Wei; Zhang, Wenyao
2017-05-01
Stress corrosion is the major failure type of bridge cable damage. The acoustic emission (AE) technique was applied to monitor the stress corrosion process of steel wires used in bridge cable structures. The damage evolution of stress corrosion in bridge cables was obtained according to the AE characteristic parameter figure. A particle swarm optimization cluster method was developed to determine the relationship between the AE signal and stress corrosion mechanisms. Results indicate that the main AE sources of stress corrosion in bridge cables included four types: passive film breakdown and detachment of the corrosion product, crack initiation, crack extension, and cable fracture. By analyzing different types of clustering data, the mean value of each damage pattern's AE characteristic parameters was determined. Different corrosion damage source AE waveforms and the peak frequency were extracted. AE particle swarm optimization cluster analysis based on principal component analysis was also proposed. This method can completely distinguish the four types of damage sources and simplifies the determination of the evolution process of corrosion damage and broken wire signals. Copyright © 2017. Published by Elsevier B.V.
Measuring adverse events in helicopter emergency medical services: establishing content validity.
Patterson, P Daniel; Lave, Judith R; Martin-Gill, Christian; Weaver, Matthew D; Wadas, Richard J; Arnold, Robert M; Roth, Ronald N; Mosesso, Vincent N; Guyette, Francis X; Rittenberger, Jon C; Yealy, Donald M
2014-01-01
We sought to create a valid framework for detecting adverse events (AEs) in the high-risk setting of helicopter emergency medical services (HEMS). We assembled a panel of 10 expert clinicians (n = 6 emergency medicine physicians and n = 4 prehospital nurses and flight paramedics) affiliated with a large multistate HEMS organization in the Northeast US. We used a modified Delphi technique to develop a framework for detecting AEs associated with the treatment of critically ill or injured patients. We used a widely applied measure, the content validity index (CVI), to quantify the validity of the framework's content. The expert panel of 10 clinicians reached consensus on a common AE definition and four-step protocol/process for AE detection in HEMS. The consensus-based framework is composed of three main components: (1) a trigger tool, (2) a method for rating proximal cause, and (3) a method for rating AE severity. The CVI findings isolate components of the framework considered content valid. We demonstrate a standardized process for the development of a content-valid framework for AE detection. The framework is a model for the development of a method for AE identification in other settings, including ground-based EMS.
The role of acoustic emission in the study of rock fracture
Lockner, D.
1993-01-01
The development of faults and shear fracture systems over a broad range of temperature and pressure and for a variety of rock types involves the growth and interaction of microcracks. Acoustic emission (AE), which is produced by rapid microcrack growth, is a ubiquitous phenomenon associated with brittle fracture and has provided a wealth of information regarding the failure process in rock. This paper reviews the successes and limitations of AE studies as applied to the fracture process in rock with emphasis on our ability to predict rock failure. Application of laboratory AE studies to larger scale problems related to the understanding of earthquake processes is also discussed. In this context, laboratory studies can be divided into the following categories. 1) Simple counting of the number of AE events prior to sample failure shows a correlation between AE rate and inelastic strain rate. Additional sorting of events by amplitude has shown that AE events obey the power law frequency-magnitude relation observed for earthquakes. These cumulative event count techniques are being used in conjunction with damage mechanics models to determine how damage accumulates during loading and to predict failure. 2) A second area of research involves the location of hypocenters of AE source events. This technique requires precise arrival time data of AE signals recorded over an array of sensors that are essentially a miniature seismic net. Analysis of the spatial and temporal variation of event hypocenters has improved our understanding of the progression of microcrack growth and clustering leading to rock failure. Recently, fracture nucleation and growth have been studied under conditions of quasi-static fault propagation by controlling stress to maintain constant AE rate. 3) A third area of study involves the analysis of full waveform data as recorded at receiver sites. One aspect of this research has been to determine fault plane solutions of AE source events from first motion data. These studies show that in addition to pure tensile and double couple events, a significant number of more complex event types occur in the period leading to fault nucleation. 4) P and S wave velocities (including spatial variations) and attenuation have been obtained by artificially generating acoustic pulses which are modified during passage through the sample. ?? 1993.
Perrin, Allison; Sherman, Steven; Pal, Sumanta; Chua, Andrew; Gorritz, Magdaliz; Liu, Zhimei; Wang, Xufang; Culver, Kenneth; Casciano, Roman; Garrison, Louis P
2015-03-01
Everolimus and axitinib are approved in the US to treat patients with advanced renal cell carcinoma (RCC) after failure on sunitinib or sorafenib, and one prior systemic therapy (e.g., sunitinib), respectively. Two indirect comparisons performed to evaluate progression-free survival in patients treated with everolimus vs axitinib suggested similar efficacy between the two treatments. Therefore, this analysis compares the lifetime costs of these two therapies among sunitinib-refractory advanced RCC patients from a US payer perspective. A Markov model was developed to simulate a cohort of sunitinib-refractory advanced RCC patients and estimate the cost of treating patients with everolimus vs axitinib. The following health states were included: stable disease without adverse events (AEs), stable disease with AEs, disease progression (PD), and death. The model included the following resources: active treatments, post-progression treatments, adverse events, physician and nurse visits, scans and tests, and palliative care. Resource utilization inputs were derived from a US claims database analysis. Additionally, a 3% annual discount rate was applied to costs, and the robustness of the model results was tested by conducting sensitivity analyses, including those on dosing scheme and post-progression treatment costs. Base case results demonstrated that patients treated with everolimus cost an average of $12,985 (11%) less over their lifetimes than patients treated with axitinib. The primary difference in costs was related to active treatment, which was largely driven by axitinib's higher dose intensity. RESULTS remained consistent across sensitivity analyses for AE and PD treatment costs, as well as dose intensity and discount rates. The results suggest that everolimus likely leads to lower lifetime costs than axitinib for sunitinib-refractory advanced RCC patients in the US.
A secure 3-way routing protocols for intermittently connected mobile ad hoc networks.
Sekaran, Ramesh; Parasuraman, Ganesh Kumar
2014-01-01
The mobile ad hoc network may be partially connected or it may be disconnected in nature and these forms of networks are termed intermittently connected mobile ad hoc network (ICMANET). The routing in such disconnected network is commonly an arduous task. Many routing protocols have been proposed for routing in ICMANET since decades. The routing techniques in existence for ICMANET are, namely, flooding, epidemic, probabilistic, copy case, spray and wait, and so forth. These techniques achieve an effective routing with minimum latency, higher delivery ratio, lesser overhead, and so forth. Though these techniques generate effective results, in this paper, we propose novel routing algorithms grounded on agent and cryptographic techniques, namely, location dissemination service (LoDiS) routing with agent AES, A-LoDiS with agent AES routing, and B-LoDiS with agent AES routing, ensuring optimal results with respect to various network routing parameters. The algorithm along with efficient routing ensures higher degree of security. The security level is cited testing with respect to possibility of malicious nodes into the network. This paper also aids, with the comparative results of proposed algorithms, for secure routing in ICMANET.
A Secure 3-Way Routing Protocols for Intermittently Connected Mobile Ad Hoc Networks
Parasuraman, Ganesh Kumar
2014-01-01
The mobile ad hoc network may be partially connected or it may be disconnected in nature and these forms of networks are termed intermittently connected mobile ad hoc network (ICMANET). The routing in such disconnected network is commonly an arduous task. Many routing protocols have been proposed for routing in ICMANET since decades. The routing techniques in existence for ICMANET are, namely, flooding, epidemic, probabilistic, copy case, spray and wait, and so forth. These techniques achieve an effective routing with minimum latency, higher delivery ratio, lesser overhead, and so forth. Though these techniques generate effective results, in this paper, we propose novel routing algorithms grounded on agent and cryptographic techniques, namely, location dissemination service (LoDiS) routing with agent AES, A-LoDiS with agent AES routing, and B-LoDiS with agent AES routing, ensuring optimal results with respect to various network routing parameters. The algorithm along with efficient routing ensures higher degree of security. The security level is cited testing with respect to possibility of malicious nodes into the network. This paper also aids, with the comparative results of proposed algorithms, for secure routing in ICMANET. PMID:25136697
NASA Astrophysics Data System (ADS)
Pasaribu, Hendra; Sitanggang, Delima; Rizki Damanik, Rudolfo; Rudianto Sitompul, Alex Chandra
2018-04-01
File transfer by using a smartphone has some security issues like data theft by irresponsible parties. To improve the quality of data security systems on smartphones, in this research the integration of AES 256 bit algorithm by using MD5 hashing is proposed. The use of MD5 aims to increase the key strength of the encryption and decryption process of document files. The test results show that the proposed method can increase the key strength of the encryption and decryption process in the document file. Encryption and decryption time by using AES and MD5 combination is faster than using AES only on *.txt file type and reverse results for *.docx, *.xlsx, *.pptx and *.pdf file files.
Comparision of ICP-OES and MP-AES in determing soil nutrients by Mechlich3 method
NASA Astrophysics Data System (ADS)
Tonutare, Tonu; Penu, Priit; Krebstein, Kadri; Rodima, Ako; Kolli, Raimo; Shanskiy, Merrit
2014-05-01
Accurate, routine testing of nutrients in soil samples is critical to understanding soil potential fertility. There are different factors which must be taken into account selecting the best analytical technique for soil laboratory analysis. Several techniques can provide adequate detection range for same analytical subject. In similar cases the choise of technique will depend on factors such as sample throughput, required infrastructure, ease of use, used chemicals and need for gas supply and operating costs. Mehlich 3 extraction method is widely used for the determination of the plant available nutrient elements contents in agricultural soils. For determination of Ca, K, and Mg from soil extract depending of laboratory ICP and AAS techniques are used, also flame photometry for K in some laboratories. For the determination of extracted P is used ICP or Vis spectrometry. The excellent sensitivity and wide working range for all extracted elements make ICP a nearly ideal method, so long as the sample throughput is big enough to justify the initial capital outlay. Other advantage of ICP techniques is the multiplex character (simultaneous acquisition of all wavelengths). Depending on element the detection limits are in range 0.1 - 1000 μg/L. For smaller laboratories with low sample throughput requirements the use of AAS is more common. Flame AAS is a fast, relatively cheap and easy technique for analysis of elements. The disadvantages of the method is single element analysis and use of flammable gas, like C2H2 and oxidation gas N2O for some elements. Detection limits of elements for AAS lays from 1 to 1000 μg/L. MP-AES offers a unique alternative to both, AAS and ICP-OES techniques with its detection power, speed of analysis. MP-AES is quite new, simple and relatively inexpensive multielemental technique, which is use self-sustained atmospheric pressure microwave plasma (MP) using nitrogen gas generated by nitrogen generator. Therefore not needs for argon and flammable (C2H2) gases, cylinder handling and the running costs of equipment are low. Detection limits of elements for MP-AES lays between the AAS and ICP ones. The objective of this study was to compare the results of soil analysis using two multielemental analytical methods - ICP-OES and MP-AES. In the experiment, different soil types with various texture, content of organic matter and pH were used. For the study soil samples of Albeluvisols, Leptosols, Cambisols, Regosols and Histosols were used . The plant available nutrients were estimated by Mehlich 3 extraction. The ICP-OES analysis were provided in the Estonian Agricultural Research Centre and MP-AES analysis in department of Soil Science and Agrochemistry at Estonian University of Life Sciences. The detection limits and limits of quantification of Ca, K, Mg and P in extracts are calculated and reported.
Cascade Distiller System Performance Testing Interim Results
NASA Technical Reports Server (NTRS)
Callahan, Michael R.; Pensinger, Stuart; Sargusingh, Miriam J.
2014-01-01
The Cascade Distillation System (CDS) is a rotary distillation system with potential for greater reliability and lower energy costs than existing distillation systems. Based upon the results of the 2009 distillation comparison test (DCT) and recommendations of the expert panel, the Advanced Exploration Systems (AES) Water Recovery Project (WRP) project advanced the technology by increasing reliability of the system through redesign of bearing assemblies and improved rotor dynamics. In addition, the project improved the CDS power efficiency by optimizing the thermoelectric heat pump (TeHP) and heat exchanger design. Testing at the NASA-JSC Advanced Exploration System Water Laboratory (AES Water Lab) using a prototype Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell d International, Torrance, Calif.) with test support equipment and control system developed by Johnson Space Center was performed to evaluate performance of the system with the upgrades as compared to previous system performance. The system was challenged with Solution 1 from the NASA Exploration Life Support (ELS) distillation comparison testing performed in 2009. Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. A secondary objective of this testing is to evaluate the performance of the CDS as compared to the state of the art Distillation Assembly (DA) used in the ISS Urine Processor Assembly (UPA). This was done by challenging the system with ISS analog waste streams. This paper details the results of the AES WRP CDS performance testing.
NASA Technical Reports Server (NTRS)
Wisner, Brian; Cabal, Mike; Vanniamparambiland, Prashanth A.; Leser, William; Hochhalter, Jacob; Kontsos, Antonios
2015-01-01
A novel technique using Scanning Electron Microscopy (SEM) in conjunction with Acoustic Emission (AE) monitoring is proposed to investigate microstructure-sensitive fatigue and fracture of metals. The coupling between quasi in situ microscopy with actual in situ nondestructive evaluation falls into the ICME framework and the idea of quantitative data-driven characterization of material behavior. To validate the use of AE monitoring inside the SEM chamber, Aluminum 2024-B sharp notch specimen were tested both inside and outside the microscope using a small scale mechanical testing device. Subsequently, the same type of specimen was tested inside the SEM chamber. Load data were correlated with both AE information and observations of microcracks around grain boundaries as well as secondary cracks, voids, and slip bands. The preliminary results are in excellent agreement with similar findings at the mesoscale. Extensions of the application of this novel technique are discussed.
Acoustic emission strand burning technique for motor burning rate prediction
NASA Technical Reports Server (NTRS)
Christensen, W. N.
1978-01-01
An acoustic emission (AE) method is being used to measure the burning rate of solid propellant strands. This method has a precision of 0.5% and excellent burning rate correlation with both subscale and large rocket motors. The AE procedure burns the sample under water and measures the burning rate from the acoustic output. The acoustic signal provides a continuous readout during testing, which allows complete data analysis rather than the start-stop clockwires used by the conventional method. The AE method helps eliminate such problems as inhibiting the sample, pressure increase and temperature rise, during testing.
Fine characterization rock thermal damage by acoustic emission technique
NASA Astrophysics Data System (ADS)
Kong, Biao; Li, Zenghua; Wang, Enyuan
2018-02-01
This paper examines the differences in the thermal mechanical properties and acoustic emission (AE) characteristics during the deformation and fracture of rock under the action of continuous heating and after high-temperature treatment. Using AE 3D positioning technology, the development and evolution of the internal thermal cracks and the time domain of AE signals in rock were analyzed. High-temperature treatment causes thermal damage to rock. Under the action of continuous heating, the phase characteristics of AE time series correspond to the five stages of rock thermal deformation and fracture, respectively: the micro-defect development stage, the threshold interval of rock micro-cracks, the crack initiation stage, the crack propagation stage, and the crack multistage propagation evolution. When the initial crack propagates, the crack initiation of the rock causes the AE signal to produce a sudden mutation change. Mechanical fraction characteristics during rock uniaxial compression after temperature treatment indicated that the decrease rate of the rock compressive strength, wave velocity, and elastic modulus are relatively large during uniaxial compression tests after high-temperature treatment. During the deformation and fracture of rock under loading, there is faster growth of AE counts and AE events, indicating an increase in the speed of rock deformation and fracture under loading. AE counts show obvious changes during the latter loading stages, whereas AE events show obvious changes during the loading process. The results obtained are valuable for rock thermal stability detection and evaluation in actual underground engineering.
Report on the Development of the Advanced Encryption Standard (AES)
Nechvatal, James; Barker, Elaine; Bassham, Lawrence; Burr, William; Dworkin, Morris; Foti, James; Roback, Edward
2001-01-01
In 1997, the National Institute of Standards and Technology (NIST) initiated a process to select a symmetric-key encryption algorithm to be used to protect sensitive (unclassified) Federal information in furtherance of NIST’s statutory responsibilities. In 1998, NIST announced the acceptance of 15 candidate algorithms and requested the assistance of the cryptographic research community in analyzing the candidates. This analysis included an initial examination of the security and efficiency characteristics for each algorithm. NIST reviewed the results of this preliminary research and selected MARS, RC™, Rijndael, Serpent and Twofish as finalists. Having reviewed further public analysis of the finalists, NIST has decided to propose Rijndael as the Advanced Encryption Standard (AES). The research results and rationale for this selection are documented in this report. PMID:27500035
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vinogradov, A.; Laboratory of Hybrid Nanostructured Materials, NITU MISiS, Moscow 119490; Yasnikov, I. S.
2014-06-21
We demonstrate that the fractal dimension (FD) of the dislocation population in a deforming material is an important quantitative characteristic of the evolution of the dislocation structure. Thus, we show that peaking of FD signifies a nearing loss of uniformity of plastic flow and the onset of strain localization. Two techniques were employed to determine FD: (i) inspection of surface morphology of the deforming crystal by white light interferometry and (ii) monitoring of acoustic emission (AE) during uniaxial tensile deformation. A connection between the AE characteristics and the fractal dimension determined from surface topography measurements was established. As a commonmore » platform for the two methods, the dislocation density evolution in the bulk was used. The relations found made it possible to identify the occurrence of a peak in the median frequency of AE as a harbinger of plastic instability leading to necking. It is suggested that access to the fractal dimension provided by AE measurements and by surface topography analysis makes these techniques important tools for monitoring the evolution of the dislocation structure during plastic deformation—both as stand-alone methods and especially when used in tandem.« less
Chen, Yen-I; Kunda, Rastislav; Storm, Andrew C; Aridi, Hanaa Dakour; Thompson, Christopher C; Nieto, Jose; James, Theodore; Irani, Shayan; Bukhari, Majidah; Gutierrez, Olaya Brewer; Agarwal, Amol; Fayad, Lea; Moran, Robert; Alammar, Nuha; Sanaei, Omid; Canto, Marcia I; Singh, Vikesh K; Baron, Todd H; Khashab, Mouen A
2018-05-01
EUS-guided gastroenterostomy (EUS-GE) is a developing modality in the management of gastric outlet obstruction (GOO) with several technical approaches, including the direct and balloon-assisted techniques. The aim of this study was to compare the direct with the balloon-assisted modality while further defining the role of EUS-GE in GOO. This multicenter, retrospective study involved consecutive patients who underwent EUS-GE with the direct or balloon-assisted technique for GOO (January 2014 to October 2016). The primary outcome was technical success. Secondary outcomes were success (ability to tolerate at least a full fluid diet), procedure time, and rate/severity of adverse events (AEs). A total of 74 patients (44.6% women; mean age 63.0 ± 11.7 years) underwent EUS-GE for GOO (direct gastroenterostomy, n = 52; balloon-assisted gastroenterostomy, n = 22). GOO was of malignant and benign etiology in 66.2% and 33.8% of patients, respectively. Technical success was achieved in 94.2% of the direct and 90.9% of the balloon-assisted approach (P = .63). Mean procedure time was shorter with the direct technique (35.7 ± 32.1 minutes vs 89.9 ± 33.3 minutes, P < .001). The clinical success rate was 92.3% for the direct technique and 90.9% for the balloon-assisted modality (P = 1.00), with a mean time to oral intake of 1.32 ± 2.76 days. The AE rate was 6.8% with only 1 severe AE noted. Rate of AEs, postprocedure length of stay, need for reintervention, and survival were similar between the 2 groups. EUS-GE is effective and safe in the management of GOO. The direct technique may be the preferred method given its shorter procedure time when compared with the balloon-assisted approach. Prospective trials are needed to confirm these findings. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
HOffert, M. J.; Weise, E.; Clow, J.; Hirzel, J.; Leeder, B.; Molyneux, S.; Scutti, N.; Spartalis, S.; Takuhara, C.
2014-12-01
(Abstract only) Six beginning astronomy students, part of an undergraduate stellar astronomy course, one advanced undergraduate student assistant, and a professor measured the position angles and separations of Washington Double Stars (WDS) J05460+2119 (= WDS J05460+2119AB; also known as ARY 6 AD and ARY 6 AE). The measurements were made at the Manzanita Observatory (116º 20' 42" W, 32º 44' 5" N) of the Tierra Astronomical Institute on 10 Blackwood Road in Boulevard, California (www.youtube.com/watch?v=BHVdeMGBGDU), at an elevation of 4,500 ft. A Celestron 11-inch HD Edge telescope was used to measure the position angles and separations of ARY 6 AD and ARY 6 AE. The averages of our measurements are as follows: separation AD: trial 1 124.1 arcseconds and trial 2 124.5 arcseconds; separation AE: trial 1 73.3 arcseconds and trial 2 73.8 arcseconds. The averages of positon angle for AD: trial 1 159.9 degrees and trial 2 161.3 degrees, for AE: trial 1 232.6 degrees and trial 2 233.7 degrees.
NASA Astrophysics Data System (ADS)
Hoffert, Michael J.; Weise, Eric; Clow, Jenna; Hirzel, Jacquelyn; Leeder, Brett; Molyneux, Scott; Scutti, Nicholas; Spartalis, Sarah; Tokuhara, Corey
2014-05-01
Six beginning astronomy students, part of an undergraduate stellar astronomy course, one advanced undergraduate student assistant, and a professor measured the position angles and separations of Washington Double Stars (WDS) 05460 + 2119 (also known as ARY 6 AD and ARY 6 AE). The measurements were made at the Manzanita Observatory (116° 20'42" W, 32° 44' 5" N) of the Tierra Astronomical Institute on 10 Blackwood Rd. in Boulevard, California (www.youtube.com/watch?v=BHVdcMGBGDU), at an elevation of 4,500 ft. A Celestron 11" HD Edge telescope was used to measure the position angles and separations of ARY 6 AD and ARY 6 AE. The averages of our measurements are as follows: separation AD: trial 1 124.1 arcseconds and trial 2 124.5 arcseconds. The average of separation for AE: trial 1 73.3 arcseconds and trial 2 73.8 arcseconds. The averages of position angle for AD: trial 1 159.9 degrees and trial 2 161.3 degrees. The averages of position angle for AE: trial 1 232.6 degrees and trial 2 233.7 degrees.
NASA Astrophysics Data System (ADS)
Das, Suman; Sadique Uz Zaman, J. K. M.; Ghosh, Ranjan
2016-06-01
In Advanced Encryption Standard (AES), the standard S-Box is conventionally generated by using a particular irreducible polynomial {11B} in GF(28) as the modulus and a particular additive constant polynomial {63} in GF(2), though it can be generated by many other polynomials. In this paper, it has been shown that it is possible to generate secured AES S-Boxes by using some other selected modulus and additive polynomials and also can be generated randomly, using a PRNG like BBS. A comparative study has been made on the randomness of corresponding AES ciphertexts generated, using these S-Boxes, by the NIST Test Suite coded for this paper. It has been found that besides using the standard one, other moduli and additive constants are also able to generate equally or better random ciphertexts; the same is true for random S-Boxes also. As these new types of S-Boxes are user-defined, hence unknown, they are able to prevent linear and differential cryptanalysis. Moreover, they act as additional key-inputs to AES, thus increasing the key-space.
Guthrie, H D; Welch, G R
2005-01-01
Flow cytometry was utilised to determine whether short-term (Day 1) or long-term hypothermic liquid storage (Day 5), or cryopreservation of boar spermatozoa (1) caused changes in plasma membrane phospholipid disorder (MPLD) and acrosome exocytosis (AE), indicative of an advanced stage of capacitation or acrosome status, and (2) facilitated or inhibited the induction of capacitation and the acrosome reaction. Merocyanine with Yo-Pro-1 and peanut agglutinin-fluorescein isothiocyanate with propidium iodide were used to identify MPLD and AE, respectively, in viable spermatozoa. The incidence of basal sperm MPLD and AE in fresh semen was very low (1.1 and 2.2%, respectively) and was increased (P < 0.05) only a small amount in Day 5 and cryopreserved semen (3-8%). Compared to no bicarbonate, incubation with bicarbonate increased MPLD, but the response was greatest (P < 0.05) in fresh sperm (52.3%) compared with Day 1 (36.6%), Day 5 (13.9%) and cryopreserved sperm (13.6%). Incubation with calcium ionophore A23187 increased AE in spermatozoa, but the response was less (P < 0.05) for fresh (34%) and cryopreserved (27%) semen than for Day 1 (45%) and Day 5 (57%) semen. In summary, hypothermic liquid storage and cryopreservation of boar spermatozoa did not advance capacitation or acrosome status in viable spermatozoa, but did alter their responses to induction of capacitation and the acrosome reaction.
NASA Advanced Exploration Systems: Advancements in Life Support Systems
NASA Technical Reports Server (NTRS)
Shull, Sarah A.; Schneider, Walter F.
2016-01-01
The NASA Advanced Exploration Systems (AES) Life Support Systems (LSS) project strives to develop reliable, energy-efficient, and low-mass spacecraft systems to provide environmental control and life support systems (ECLSS) critical to enabling long duration human missions beyond low Earth orbit (LEO). Highly reliable, closed-loop life support systems are among the capabilities required for the longer duration human space exploration missions assessed by NASA’s Habitability Architecture Team.
NASA Astrophysics Data System (ADS)
Michlmayr, Gernot; Cohen, Denis; Or, Dani
2012-05-01
The formation of cracks and emergence of shearing planes and other modes of rapid macroscopic failure in geologic granular media involve numerous grain scale mechanical interactions often generating high frequency (kHz) elastic waves, referred to as acoustic emissions (AE). These acoustic signals have been used primarily for monitoring and characterizing fatigue and progressive failure in engineered systems, with only a few applications concerning geologic granular media reported in the literature. Similar to the monitoring of seismic events preceding an earthquake, AE may offer a means for non-invasive, in-situ, assessment of mechanical precursors associated with imminent landslides or other types of rapid mass movements (debris flows, rock falls, snow avalanches, glacier stick-slip events). Despite diverse applications and potential usefulness, a systematic description of the AE method and its relevance to mechanical processes in Earth sciences is lacking. This review is aimed at providing a sound foundation for linking observed AE with various micro-mechanical failure events in geologic granular materials, not only for monitoring of triggering events preceding mass mobilization, but also as a non-invasive tool in its own right for probing the rich spectrum of mechanical processes at scales ranging from a single grain to a hillslope. We review first studies reporting use of AE for monitoring of failure in various geologic materials, and describe AE generating source mechanisms in mechanically stressed geologic media (e.g., frictional sliding, micro-crackling, particle collisions, rupture of water bridges, etc.) including AE statistical features, such as frequency content and occurrence probabilities. We summarize available AE sensors and measurement principles. The high sampling rates of advanced AE systems enable detection of numerous discrete failure events within a volume and thus provide access to statistical descriptions of progressive collapse of systems with many interacting mechanical elements such as the fiber bundle model (FBM). We highlight intrinsic links between AE characteristics and established statistical models often used in structural engineering and material sciences, and outline potential applications for failure prediction and early-warning using the AE method in combination with the FBM. The biggest challenge to application of the AE method for field applications is strong signal attenuation. We provide an outlook for overcoming such limitations considering emergence of a class of fiber-optic based distributed AE sensors and deployment of acoustic waveguides as part of monitoring networks.
Acoustic Emission Monitoring of Multicell Reinforced Concrete Box Girders Subjected to Torsion
Bagherifaez, Marya; Behnia, Arash; Majeed, Abeer Aqeel; Hwa Kian, Chai
2014-01-01
Reinforced concrete (RC) box girders are a common structural member for road bridges in modern construction. The hollow cross-section of a box girder is ideal in carrying eccentric loads or torques introduced by skew supports. This study employed acoustic emission (AE) monitoring on multicell RC box girder specimens subjected to laboratory-based torsion loading. Three multicell box girder specimens with different cross-sections were tested. The aim is to acquire AE analysis data indicative for characterizing torsion fracture in the box girders. It was demonstrated through appropriate parametric analysis that the AE technique could be utilized to effectively classify fracture developed in the specimens for describing their mechanical behavior under torsion. AE events localization was presented to illustrate the trend of crack and damage propagation in different stages of fracture. It could be observed that spiral-like patterns of crack were captured through AE damage localization system and damage was quantified successfully in different stages of fracture by using smoothed b-value analysis. PMID:25180203
Measuring Adverse Events in Helicopter Emergency Medical Services: Establishing Content Validity
Patterson, P. Daniel; Lave, Judith R.; Martin-Gill, Christian; Weaver, Matthew D.; Wadas, Richard J.; Arnold, Robert M.; Roth, Ronald N.; Mosesso, Vincent N.; Guyette, Francis X.; Rittenberger, Jon C.; Yealy, Donald M.
2015-01-01
Introduction We sought to create a valid framework for detecting Adverse Events (AEs) in the high-risk setting of Helicopter Emergency Medical Services (HEMS). Methods We assembled a panel of 10 expert clinicians (n=6 emergency medicine physicians and n=4 prehospital nurses and flight paramedics) affiliated with a large multi-state HEMS organization in the Northeast U.S. We used a modified Delphi technique to develop a framework for detecting AEs associated with the treatment of critically ill or injured patients. We used a widely applied measure, the Content Validity Index (CVI), to quantify the validity of the framework’s content. Results The expert panel of 10 clinicians reached consensus on a common AE definition and four-step protocol/process for AE detection in HEMS. The consensus-based framework is composed of three main components: 1) a trigger tool, 2) a method for rating proximal cause, and 3) a method for rating AE severity. The CVI findings isolate components of the framework considered content valid. Conclusions We demonstrate a standardized process for the development of a content valid framework for AE detection. The framework is a model for the development of a method for AE identification in other settings, including ground-based EMS. PMID:24003951
Cryogenics Testbed Laboratory Flange Baseline Configuration
NASA Technical Reports Server (NTRS)
Acuna, Marie Lei Ysabel D.
2013-01-01
As an intern at Kennedy Space Center (KSC), I was involved in research for the Fluids and Propulsion Division of the NASA Engineering (NE) Directorate. I was immersed in the Integrated Ground Operations Demonstration Units (IGODU) project for the majority of my time at KSC, primarily with the Ground Operations Demonstration Unit Liquid Oxygen (GODU L02) branch of IGODU. This project was established to develop advancements in cryogenic systems as a part of KSC's Advanced Exploration Systems (AES) program. The vision of AES is to develop new approaches for human exploration, and operations in and beyond low Earth orbit. Advanced cryogenic systems are crucial to minimize the consumable losses of cryogenic propellants, develop higher performance launch vehicles, and decrease operations cost for future launch programs. During my internship, I conducted a flange torque tracking study that established a baseline configuration for the flanges in the Simulated Propellant Loading System (SPLS) at the KSC Cryogenics Test Laboratory (CTL) - the testing environment for GODU L02.
Ito, Yoshinori; Masuda, Norikazu; Iwata, Hiroji; Mukai, Hirofumi; Horiguchi, Jun; Tokuda, Yutaka; Kuroi, Katsumasa; Mori, Asuka; Ohno, Nobutsugu; Noguchi, Shinzaburo
2015-01-01
In a phase 3, double-blind, randomized, international study (the BOLERO-2), the addition of mTOR inhibitor everolimus to exemestane was evaluated in postmenopausal women with estrogen-receptor-positive (ER⁺) advanced/recurrent breast cancer that was refractory to any nonsteroidal aromatase inhibitor (NSAI). This report presents the safety and updated (18- month) efficacy results from the Japanese subset (n=106) of BOLERO-2. After a median follow-up of 18 months, the median progression-free survival time was 8.5 months with everolimus plus exemestane compared to 4.2 months with placebo plus exemestane. The most common adverse events (AEs) with everolimus plus exemestane were stomatitis, rash, dysgeusia, and non-infectious lung disease. The AEs reported with the combination therapy were mostly of grade 1 or 2 and manageable with appropriate intervention. In conclusion, this combination could be a useful addition to the armamentarium of treatments for Japanese postmenopausal women with ER⁺ advanced/recurrent breast cancer progressing on NSAIs.
Managing adverse effects of immunotherapy.
Gerson, James N; Ramamurthy, Chethan; Borghaei, Hossein
2018-05-01
Remarkable efficacy has been achieved in a variety of cancer types by targeting immune checkpoints. The cytotoxic T-lymphocyte-associated antigen 4 inhibitor ipilimumab, the programmed death 1 inhibitors nivolumab and pembrolizumab, and the programmed death ligand 1 inhibitors atezolizumab, avelumab, and durvalumab are the agents currently approved by the US Food and Drug Administration for the treatment of certain advanced malignancies. These agents mark a departure from both standard cytotoxic chemotherapy and targeted therapy. However, they are associated with a unique set of immune-related adverse events (irAEs), which can manifest as a wide range of autoimmune phenomena. The irAEs can affect any system in the body and in rare cases are life-threatening. It is critical for the practicing medical oncologist to recognize and promptly treat any irAEs that may develop.
Harmonization in preclinical epilepsy research: A joint AES/ILAE translational initiative.
Galanopoulou, Aristea S; French, Jacqueline A; O'Brien, Terence; Simonato, Michele
2017-11-01
Among the priority next steps outlined during the first translational epilepsy research workshop in London, United Kingdom (2012), jointly organized by the American Epilepsy Society (AES) and the International League Against Epilepsy (ILAE), are the harmonization of research practices used in preclinical studies and the development of infrastructure that facilitates multicenter preclinical studies. The AES/ILAE Translational Task Force of the ILAE has been pursuing initiatives that advance these goals. In this supplement, we present the first reports of the working groups of the Task Force that aim to improve practices of performing rodent video-electroencephalography (vEEG) studies in experimental controls, generate systematic reviews of preclinical research data, and develop preclinical common data elements (CDEs) for epilepsy research in animals. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.
Kim, Jong-Min; Chung, Sun Ju; Kim, Jae Woo; Jeon, Beom Seok; Singh, Pritibha; Thierfelder, Stephan; Ikeda, Junji; Bauer, Lars
2015-02-28
Achieving optimal symptom control with minimal side effects is a major goal in clinical practice. Dual-agent dopamine receptor agonist (DA) therapy in Parkinson's disease (PD) may represent a promising approach to treatment, as the combination of different pharmacokinetic/pharmacological profiles may result in a lesser need for high dosages and, accordingly, may be well tolerated. The objective of the current study was to investigate safety and efficacy of rotigotine transdermal system as add-on to oral DA in patients with advanced PD inadequately controlled with levodopa and low-dose oral DA. PD0015 was an open-label, multinational study in patients with advanced-PD and sleep disturbance or early-morning motor impairment. Patients were titrated to optimal dose rotigotine (≤8 mg/24 h) over 1-4 weeks and maintained for 4-7 weeks (8-week treatment). Dosage of levodopa and oral DA (pramipexole ≤1.5 mg/day, ropinirole ≤6.0 mg/day) was stable. Primary variable was Clinical Global Impressions (CGI) item 4: side effects, assessing safety. Other variables included adverse events (AEs), Patient Global Impressions of Change (PGIC), Unified Parkinson's Disease Rating Scale (UPDRS) II and III, Parkinson's Disease Sleep Scale (PDSS-2), Pittsburgh Sleep Quality Index (PSQI), and "off" time. Of 90 patients who received rotigotine, 79 (88%) completed the study; 5 (6%) withdrew due to AEs. Most (83/89; 93%) had a CGI-4 score <3 indicating that rotigotine add-on therapy did not interfere with functioning; 6 (7%) experienced drug-related AEs that interfered with functioning (score ≥3). AEs occurring in ≥5% were application site pruritus (13%), dizziness (10%), orthostatic hypotension (10%), nausea (8%), dyskinesia (8%), and nasopharyngitis (6%). Numerical improvements in motor function (UPDRS III), activities of daily living (UPDRS II), sleep disturbances (PDSS-2, PSQI), and reduction in "off" time were observed. The majority (71/88; 81%) improved on PGIC. Addition of rotigotine transdermal system to low-dose oral DA in patients with advanced-PD was feasible and may be associated with clinical benefit. ClinicalTrials.gov identifier NCT01723904 . Trial registration date: November 6, 2012.
Detection of Delamination in Composite Beams Using Broadband Acoustic Emission Signatures
NASA Technical Reports Server (NTRS)
Okafor, A. C.; Chandrashekhara, K.; Jiang, Y. P.
1996-01-01
Delamination in composite structure may be caused by imperfections introduced during the manufacturing process or by impact loads by foreign objects during the operational life. There are some nondestructive evaluation methods to detect delamination in composite structures such as x-radiography, ultrasonic testing, and thermal/infrared inspection. These methods are expensive and hard to use for on line detection. Acoustic emission testing can monitor the material under test even under the presence of noise generated under load. It has been used extensively in proof-testing of fiberglass pressure vessels and beams. In the present work, experimental studies are conducted to investigate the use of broadband acoustic emission signatures to detect delaminations in composite beams. Glass/epoxy beam specimens with full width, prescribed delamination sizes of 2 inches and 4 inches are investigated. The prescribed delamination is produced by inserting Teflon film between laminae during the fabrication of composite laminate. The objectives of this research is to develop a method for predicting delamination size and location in laminated composite beams by combining smart materials concept and broadband AE analysis techniques. More specifically, a piezoceramic (PZT) patch is bonded on the surface of composite beams and used as a pulser. The piezoceramic patch simulates the AE wave source as a 3 cycles, 50KHz, burst sine wave. One broadband AE sensor is fixed near the PZT patch to measure the AE wave near the AE source. A second broadband AE sensor, which is used as a receiver, is scanned along the composite beams at 0.25 inch step to measure propagation of AE wave along the composite beams. The acquired AE waveform is digitized and processed. Signal strength, signal energy, cross-correlation of AE waveforms, and tracking of specific cycle of AE waveforms are used to detect delamination size and location.
NASA Astrophysics Data System (ADS)
Du, Fangzhu; Li, Dongsheng
2018-03-01
As a new kind of composite structures, the using of steel confined reinforced concrete column attract increasing attention in civil engineer. During the damage process, this new structure offers highly complex and invisible failure mechanism due to the combination effects of steel tubes, concrete, and steel rebar. Acoustic emission (AE) technique has been extensively studied in nondestructive testing (NDT) and is currently applied in civil engineering for structural health monitoring (SHM) and damage evaluation. In the present study, damage property and failure evolution of steel confined and unconfined reinforced concrete (RC) columns are investigated under quasi-static loading through (AE) signal. Significantly improved loading capacity and excellent energy dissipation characteristic demonstrated the practicality of that proposed structure. AE monitoring results indicated that the progressive deformation of the test specimens occur in three stages representing different damage conditions. Sentry function compares the logarithm ratio between the stored strain energy (Es) and the released acoustic energy (Ea); explicitly disclose the damage growth and failure mechanism of the test specimens. Other extended AE features including index of damage (ID), and relax ratio are calculated to quantitatively evaluate the damage severity and critical point. Complicated temporal evolution of different AE features confirms the potential importance of integrated analysis of two or more parameters. The proposed multi-indicators analysis is capable of revealing the damage growth and failure mechanism for steel confined RC columns, and providing critical warning information for structure failure.
Assessment of corrosion fatigue damage by acoustic emission and periodic proof tests
NASA Astrophysics Data System (ADS)
Mehdizadeh, P.
1976-03-01
The development of a better nondestructive inspection method for detecting corrosion fatigue damage based on acoustic emission (AE) and periodic proof testing (PPT) is studied for corrosion fatigue tests in salt water solution under tension-tension loading. It is shown that PPT combined with AE monitoring can be a sensitive method for assessing the progress of corrosion fatigue damage as the continuous AE monitoring method. The AE-PPT technique is shown to be dependent on the geometry and size of the crack relative to the test specimen. A qualitative method based on plateauing of acoustic emission counts during proof tests due to changes in the fracture mode is used to predict the remaining fatigue life up to 70% of the actual values. PPT is shown to have no adverse effect on fatigue performance in salt water.
Ultrasonic emissions during ice nucleation and propagation in plant xylem.
Charrier, Guillaume; Pramsohler, Manuel; Charra-Vaskou, Katline; Saudreau, Marc; Améglio, Thierry; Neuner, Gilbert; Mayr, Stefan
2015-08-01
Ultrasonic acoustic emission analysis enables nondestructive monitoring of damage in dehydrating or freezing plant xylem. We studied acoustic emissions (AE) in freezing stems during ice nucleation and propagation, by combining acoustic and infrared thermography techniques and controlling the ice nucleation point. Ultrasonic activity in freezing samples of Picea abies showed two distinct phases: the first on ice nucleation and propagation (up to 50 AE s(-1) ; reversely proportional to the distance to ice nucleation point), and the second (up to 2.5 AE s(-1) ) after dissipation of the exothermal heat. Identical patterns were observed in other conifer and angiosperm species. The complex AE patterns are explained by the low water potential of ice at the ice-liquid interface, which induced numerous and strong signals. Ice propagation velocities were estimated via AE (during the first phase) and infrared thermography. Acoustic activity ceased before the second phase probably because the exothermal heating and the volume expansion of ice caused decreasing tensions. Results indicate cavitation events at the ice front leading to AE. Ultrasonic emission analysis enabled new insights into the complex process of xylem freezing and might be used to monitor ice propagation in natura. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Strantza, Maria; Van Hemelrijck, Danny; Guillaume, Patrick
We report that additive manufacturing (AM) is a novel and innovative production technology that can produce complex and lightweight engineering products. In AM components, as in all engineering materials, fatigue is considered as one of the principle causes of unexpected failure. In order to detect, localise and characterise cracks in various material components and metals, acoustic emission (AE) is used as a non-destructive monitoring technique. One of the main advantages of AE is that it can be also used for dynamic damage characterisation and specifically for crack propagation monitoring. In this research, we use AE to monitor the fatigue crackmore » growth behaviour of Ti6Al4V components under four-point bending. The samples were produced by means of AM as well as conventional material. Notched and unnotched specimens were investigated with respect to the crack severity and crack detection using AE. The main AE signal parameters –such as cumulative events, hits, duration, average frequency and rise time– were evaluated and indicate sensitivity to damage propagation in order to lead to a warning against the final fracture occurrence. Finally, this is the first time that AE is applied in AM components under fatigue.« less
Strantza, Maria; Van Hemelrijck, Danny; Guillaume, Patrick; ...
2017-05-31
We report that additive manufacturing (AM) is a novel and innovative production technology that can produce complex and lightweight engineering products. In AM components, as in all engineering materials, fatigue is considered as one of the principle causes of unexpected failure. In order to detect, localise and characterise cracks in various material components and metals, acoustic emission (AE) is used as a non-destructive monitoring technique. One of the main advantages of AE is that it can be also used for dynamic damage characterisation and specifically for crack propagation monitoring. In this research, we use AE to monitor the fatigue crackmore » growth behaviour of Ti6Al4V components under four-point bending. The samples were produced by means of AM as well as conventional material. Notched and unnotched specimens were investigated with respect to the crack severity and crack detection using AE. The main AE signal parameters –such as cumulative events, hits, duration, average frequency and rise time– were evaluated and indicate sensitivity to damage propagation in order to lead to a warning against the final fracture occurrence. Finally, this is the first time that AE is applied in AM components under fatigue.« less
Report on the Workshop Herbig Ae/Be Stars: The Missing Link in Star Formation
NASA Astrophysics Data System (ADS)
de Wit, W.-J.; Oudmaijer, R. D.; van den Ancker, M. E.; Calvet, N.
2014-09-01
The workshop highlighted the many recent advances within the field of Herbig Ae/Be stars and the close links to star and planet formation. Topics such as magnetospheric accretion and the evolution of dust in discs, the structure of circumstellar discs and the role of walls and gaps and their links to planet formation from many observational aspects were covered. The workshop was dedicated to the life and works of George H. Herbig, who sadly passed away at the end of last year.
Experimental realization of a highly secure chaos communication under strong channel noise
NASA Astrophysics Data System (ADS)
Ye, Weiping; Dai, Qionglin; Wang, Shihong; Lu, Huaping; Kuang, Jinyu; Zhao, Zhenfeng; Zhu, Xiangqing; Tang, Guoning; Huang, Ronghuai; Hu, Gang
2004-09-01
A one-way coupled spatiotemporally chaotic map lattice is used to construct cryptosystem. With the combinatorial applications of both chaotic computations and conventional algebraic operations, our system has optimal cryptographic properties much better than the separative applications of known chaotic and conventional methods. We have realized experiments to practice duplex voice secure communications in realistic Wired Public Switched Telephone Network by applying our chaotic system and the system of Advanced Encryption Standard (AES), respectively, for cryptography. Our system can work stably against strong channel noise when AES fails to work.
Human Alveolar Echinococcosis in Poland: 1990–2011
Nahorski, Wacław L.; Knap, Józef P.; Pawłowski, Zbigniew S.; Krawczyk, Marek; Polański, Jerzy; Stefaniak, Jerzy; Patkowski, Waldemar; Szostakowska, Beata; Pietkiewicz, Halina; Grzeszczuk, Anna; Felczak-Korzybska, Iwona; Gołąb, Elżbieta; Wnukowska, Natalia; Paul, Małgorzata; Kacprzak, Elżbieta; Sokolewicz-Bobrowska, Elżbieta; Niścigorska-Olsen, Jolanta; Czyrznikowska, Aleksandra; Chomicz, Lidia; Cielecka, Danuta; Myjak, Przemysław
2013-01-01
Background Alveolar echinococcosis (AE) caused by Echinococcus multilocularis infections is a dangerous old disease in the Northern Hemisphere. The aim of the paper was to collect and analyze data on human AE in Poland in the last two decades. Methodology/Principal Findings The sources of data were both the cases officially registered and detected by an active field and laboratory surveillance. The cases were verified by clinical, epidemiological, and laboratory criteria. Altogether 121 human cases of AE were detected. Among these 83 (68,6%) cases were classified as confirmed, 16 as probable and 22 as possible. During the two decades a continuous increase in detection rate was noticed. The cases were 6–82 years old at the time of diagnosis (mean - 47.7 years). Sex ratio M/F was 0.86/1.0. The AE was fatal in 23 (19%) patients (mean age at death - 54.1 years). Family agglomeration of AE was found in 4 foci, involving 9 patients. Seventy six of the cases were diagnosed in an advanced stage of disease. In all cases the liver was the primary location of AE. In 30 (24.8%) patients a spread to other organs was observed. Ninety four of the patients were treated with albendazole. In 73 (60%) patients a surgical operation was performed, including 15 liver transplantations. Conclusions/Significance The studies confirmed that AE is an emerging disease in Poland, which is the fourth country in Europe with over 120 cases detected. The results also indicate the need of a wider national programme for implementation of screening in the highest AE risk areas (north-eastern Poland) with an effort to increase the public awareness of the possibility of contracting E. multilocularis, and above all, training of the primary care physicians in the recognition of the risk of AE to allow for an early detection of this dangerous disease. PMID:23301116
Novel secret key generation techniques using memristor devices
NASA Astrophysics Data System (ADS)
Abunahla, Heba; Shehada, Dina; Yeun, Chan Yeob; Mohammad, Baker; Jaoude, Maguy Abi
2016-02-01
This paper proposes novel secret key generation techniques using memristor devices. The approach depends on using the initial profile of a memristor as a master key. In addition, session keys are generated using the master key and other specified parameters. In contrast to existing memristor-based security approaches, the proposed development is cost effective and power efficient since the operation can be achieved with a single device rather than a crossbar structure. An algorithm is suggested and demonstrated using physics based Matlab model. It is shown that the generated keys can have dynamic size which provides perfect security. Moreover, the proposed encryption and decryption technique using the memristor based generated keys outperforms Triple Data Encryption Standard (3DES) and Advanced Encryption Standard (AES) in terms of processing time. This paper is enriched by providing characterization results of a fabricated microscale Al/TiO2/Al memristor prototype in order to prove the concept of the proposed approach and study the impacts of process variations. The work proposed in this paper is a milestone towards System On Chip (SOC) memristor based security.
Shapiro, Geoffrey I; Bell-McGuinn, Katherine M; Molina, Julian R; Bendell, Johanna; Spicer, James; Kwak, Eunice L; Pandya, Susan S; Millham, Robert; Borzillo, Gary; Pierce, Kristen J; Han, Lixin; Houk, Brett E; Gallo, Jorge D; Alsina, Maria; Braña, Irene; Tabernero, Josep
2015-04-15
To evaluate safety (primary endpoint), tolerability, pharmacokinetics, pharmacodynamic profile, and preliminary activity of the intravenous, pan-class I isoform PI3K/mTOR inhibitor PF-05212384 in patients with advanced solid tumors. Part 1 of this open-label phase I study was designed to estimate the maximum-tolerated dose (MTD) in patients with nonselected solid tumors, using a modified continual reassessment method to guide dose escalation. Objectives of part 2 were MTD confirmation and assessment of preliminary activity in patients with selected tumor types and PI3K pathway dysregulation. Seventy-seven of the 78 enrolled patients received treatment. The MTD for PF-05212384, administered intravenously once weekly, was estimated to be 154 mg. The most common treatment-related adverse events (AE) were mucosal inflammation/stomatitis (58.4%), nausea (42.9%), hyperglycemia (26%), decreased appetite (24.7%), fatigue (24.7%), and vomiting (24.7%). The majority of patients treated at the MTD experienced only grade 1 treatment-related AEs. Grade 3 treatment-related AEs occurred in 23.8% of patients at the MTD. No treatment-related grade 4-5 AEs were reported at any dose level. Antitumor activity was noted in this heavily pretreated patient population, with two partial responses (PR) and an unconfirmed PR. Eight patients had long-lasting stable disease (>6 months). Pharmacokinetic analyses showed a biphasic concentration-time profile for PF-05212384 (half-life, 30-37 hours after multiple dosing). PF-05212384 inhibited downstream effectors of the PI3K pathway in paired tumor biopsies. These findings demonstrate the manageable safety profile and antitumor activity of the PI3K/mTOR inhibitor PF-05212384, supporting further clinical development for patients with advanced solid malignancies. ©2015 American Association for Cancer Research.
Deutsch, Eric; Moyal, Elizabeth Cohen-Jonathan; Gregorc, Vanesa; Zucali, Paolo Andrea; Menard, Jean; Soria, Jean-Charles; Kloos, Ioana; Hsu, Jeff; Luan, Ying; Liu, Emily; Vezan, Remus; Graef, Thorsten; Rivera, Sofia
2017-01-01
Current treatments for advanced solid tumors tend to be only palliative. Although radiotherapy is administered with a curative intent, radioresistance and dose-limiting toxicities pose limitations to treatment. Abexinostat, an oral pan-histone deacetylase inhibitor, demonstrated enhanced sensitivity to radiation in various solid tumor cell lines. We conducted an exploratory, phase 1, dose-escalation study of abexinostat in combination with standard hypofractionated radiotherapy in patients with advanced solid tumors treated in a palliative setting. Among 58 treated patients, the median age was 61.5 years (range, 20-82); 47% of the patients had M1 stage disease, and 95% had received previous chemotherapy alone or chemotherapy in combination with surgery and/or radiotherapy. The recommended phase 2 dose was determined to be 90 mg/m2 (140 mg). Of the 51 patients evaluable for response, best overall response was 8% (1 complete response [CR], 3 partial responses [PRs]), and best loco-regional response was 12% (1 CR and 5 PRs) at a median follow-up of 16 weeks. Of note, patients with target or non-target brain lesions showed encouraging responses, with 1 patient achieving a best loco-regional response of CR. Treatment-emergent grade ≥3 adverse events (AEs) were few, with most common being thrombocytopenia (17%), lymphopenia (12%), and hypokalemia (7%). Six patients (10%) discontinued treatment due to AEs. No grade ≥3 prolongation of the QTc interval was observed, with no treatment discontinuations due to this AE. Oral abexinostat combined with radiotherapy was well tolerated in patients with advanced solid tumors. The combination may have potential for treatment of patients with brain lesions. PMID:28915584
Safety and activity of PD-1 blockade-activated DC-CIK cells in patients with advanced solid tumors.
Chen, Chang-Long; Pan, Qiu-Zhong; Weng, De-Sheng; Xie, Chuan-Miao; Zhao, Jing-Jing; Chen, Min-Shan; Peng, Rui-Qing; Li, Dan-Dan; Wang, Ying; Tang, Yan; Wang, Qi-Jing; Zhang, Zhi-Ling; Zhang, Xiao-Fei; Jiang, Li-Juan; Zhou, Zi-Qi; Zhu, Qian; He, Jia; Liu, Yuan; Zhou, Fang-Jian; Xia, Jian-Chuan
2018-01-01
Cytokine-induced killer (CIK) cells that are stimulated using mature dendritic cells (DCs), referred to as (DC-CIK cells) exhibit superior anti-tumor potency. Anti-programmed death-1 (PD-1) antibodies reinvigorate T cell-mediated antitumor immunity. This phase I study aimed to assess the safety and clinical activity of immunotherapy with PD-1 blockade (pembrolizumab)-activated autologous DC-CIK cells in patients with advanced solid tumors. Patients with selected types of advanced solid tumors received a single intravenous infusion of activated autologous DC-CIK cells weekly for the first month and every 2 weeks thereafter. The primary end points were safety and adverse event (AE) profiles. Antitumor responses, overall survival (OS), progression-free survival (PFS) and cytolytic activity were secondary end points. Treatment-related AEs occurred in 20/31 patients. Grade 3 or 4 toxicities, including fever and chills, were observed in two patients. All treatment-related AEs were reversible or controllable. The cytotoxicity of DC-CIK cells induced up-regulation of PD-L1 expression on autologous tumor cells. When activated using pembrolizumab ex vivo , DC-CIK cells exerted superior antitumor properties and elevated IFN-γ secretion. Objective responses (complete or partial responses) were observed in 7 of the 31patients.These responses were durable, with 6 of 7 responses lasting more than 5 months. The overall disease control rate in the patients was 64.5%. At the time of this report, the median OS and PFS were 270 and 162 days, respectively. In conclusions, treatment with pembrolizumab-activated autologous DC-CIK cells was safe and exerted encouraging antitumor activity in advanced solid tumors. A larger phase II trial is warranted.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vlies, Cornelis H. van der, E-mail: c.h.vandervlies@amc.n; Delden, Otto M. van, E-mail: o.m.vandelden@amc.n; Punt, Bastiaan J., E-mail: b.j.punt@asz.n
IntroductionThe spleen is the second most frequently injured organ following blunt abdominal trauma. Trends in management have changed over the years. Traditionally, laparotomy and splenectomy was the standard management. Presently, nonoperative management (NOM) of splenic injury is the most common management strategy in hemodynamically stable patients. Splenic injuries can be managed via simple observation (OBS) or with angiography and embolization (AE). Angio-embolization has shown to be a valuable alternative to observational management and has increased the success rate of nonoperative management in many series.DiagnosticsImproved imaging techniques and advances in interventional radiology have led to a better selection of patients whomore » are amenable to nonoperative management. Despite this, there is still a lot of debate about which patients are prone to NOM.Angiography and EmbolizationThe optimal patient selection is still a matter of debate and the role of CT and angio-embolization has not yet fully evolved. We discuss the role of sonography and CT features, such as contrast extravasation, pseudoaneurysms, arteriovenous fistulas, or hemoperitoneum, to determine the optimal patient selection for angiography and embolization. We also review the efficiency, technical considerations (proximal or selective embolization), logistics, and complication rates of AE for blunt traumatic splenic injuries.« less
van Delden, Otto M.; Punt, Bastiaan J.; Ponsen, Kees J.; Reekers, Jim A.; Goslings, J. Carel
2010-01-01
Introduction The spleen is the second most frequently injured organ following blunt abdominal trauma. Trends in management have changed over the years. Traditionally, laparotomy and splenectomy was the standard management. Presently, nonoperative management (NOM) of splenic injury is the most common management strategy in hemodynamically stable patients. Splenic injuries can be managed via simple observation (OBS) or with angiography and embolization (AE). Angio-embolization has shown to be a valuable alternative to observational management and has increased the success rate of nonoperative management in many series. Diagnostics Improved imaging techniques and advances in interventional radiology have led to a better selection of patients who are amenable to nonoperative management. Despite this, there is still a lot of debate about which patients are prone to NOM. Angiography and Embolization The optimal patient selection is still a matter of debate and the role of CT and angio-embolization has not yet fully evolved. We discuss the role of sonography and CT features, such as contrast extravasation, pseudoaneurysms, arteriovenous fistulas, or hemoperitoneum, to determine the optimal patient selection for angiography and embolization. We also review the efficiency, technical considerations (proximal or selective embolization), logistics, and complication rates of AE for blunt traumatic splenic injuries. PMID:20668852
Hiding Techniques for Dynamic Encryption Text based on Corner Point
NASA Astrophysics Data System (ADS)
Abdullatif, Firas A.; Abdullatif, Alaa A.; al-Saffar, Amna
2018-05-01
Hiding technique for dynamic encryption text using encoding table and symmetric encryption method (AES algorithm) is presented in this paper. The encoding table is generated dynamically from MSB of the cover image points that used as the first phase of encryption. The Harris corner point algorithm is applied on cover image to generate the corner points which are used to generate dynamic AES key to second phase of text encryption. The embedded process in the LSB for the image pixels except the Harris corner points for more robust. Experimental results have demonstrated that the proposed scheme have embedding quality, error-free text recovery, and high value in PSNR.
NASA Astrophysics Data System (ADS)
Okafor, A. Chukwujekwu; Natarajan, Shridhar
2014-02-01
Corrosion damage affects structural integrity and deteriorates material properties of aluminum alloys in aircraft structures. Acoustic Emission (AE) is an effective nondestructive evaluation (NDE) technique for monitoring such damages and predicting failure in large structures of an aircraft. For successful interpretation of data from AE monitoring, sources of AE and factors affecting it need to be identified. This paper presents results of AE monitoring of tensile testing of corroded and un-corroded clad Aluminum 2024-T3 test specimens, and characterization of the effects of strain-rate and corrosion damage on material tensile properties and AE source events. Effect of corrosion was studied by inducing corrosion in the test specimens by accelerated corrosion testing in a Q-Fog accelerated corrosion chamber for 12 weeks. Eight (8) masked dog-bone shaped specimens were placed in the accelerated corrosion chamber at the beginning of the test. Two (2) dog-bone shaped specimens were removed from the corrosion chamber after exposure time of 3, 6, 9, and 12 weeks respectively, and subjected to tension testing till specimen failure along with AE monitoring, as well as two (2) reference samples not exposed to corrosion. Material tensile properties (yield strength, ultimate tensile strength, toughness, and elongation) obtained from tension test and AE parameters obtained from AE monitoring were analyzed and characterized. AE parameters increase with increase in exposure period of the specimens in the corrosive environment. Aluminum 2024-T3 is an acoustically silent material during tensile deformation without any damage. Acoustic emission events increase with increase of corrosion damage and with increase in strain rate above a certain value. Thus AE is suitable for structural health monitoring of corrosion damage. Ultimate tensile strength, toughness and elongation values decrease with increase of exposure period in corrosion chamber.
Acoustic emission monitoring of composite containment systems
NASA Astrophysics Data System (ADS)
Maguire, John R.
2011-07-01
This paper considers two different types of composite containment system, and two different types of acoustic emission (AE) monitoring approach. The first system is a composite reinforced pressure vessel (CRPV) which is monitored both during construction and in-service using a broadband modal acoustic emission (MAE) technique. The second system is a membrane cargo containment system which is monitored using both a global as well as a local AE technique. For the CRPV, the damage assessment is concerned mainly with the integrity of the composite outer layer at the construction stage, and possible fatigue cracking of the inner steel liner at the in-service stage. For the membrane tank, the damage assessment is concerned with locating and quantifying any abnormal porosities that might develop in-service. By comparing and contrasting the different types of structural system and different monitoring approaches inferences are drawn as to what role AE monitoring could take in the damage assessment of other types of composite containment system. (Detailed technical data have not been included, due to client confidentiality constraints.)
Decryption-decompression of AES protected ZIP files on GPUs
NASA Astrophysics Data System (ADS)
Duong, Tan Nhat; Pham, Phong Hong; Nguyen, Duc Huu; Nguyen, Thuy Thanh; Le, Hung Duc
2011-10-01
AES is a strong encryption system, so decryption-decompression of AES encrypted ZIP files requires very large computing power and techniques of reducing the password space. This makes implementations of techniques on common computing system not practical. In [1], we reduced the original very large password search space to a much smaller one which surely containing the correct password. Based on reduced set of passwords, in this paper, we parallel decryption, decompression and plain text recognition for encrypted ZIP files by using CUDA computing technology on graphics cards GeForce GTX295 of NVIDIA, to find out the correct password. The experimental results have shown that the speed of decrypting, decompressing, recognizing plain text and finding out the original password increases about from 45 to 180 times (depends on the number of GPUs) compared to sequential execution on the Intel Core 2 Quad Q8400 2.66 GHz. These results have demonstrated the potential applicability of GPUs in this cryptanalysis field.
Circulation of Chikungunya virus in Aedes aegypti in Maranhão, Northeast Brazil.
Aragão, Carine Fortes; Cruz, Ana Cecília Ribeiro; Neto, Joaquim Pinto Nunes; Monteiro, Hamilton Antonio de Oliveira; da Silva, Eliana Vieira Pinto; da Silva, Sandro Patroca; Andrade, Aylane Tamara Dos Santos; Tadei, Wanderli Pedro; Pinheiro, Valéria Cristina Soares
2018-06-19
The simultaneous circulation of Dengue virus (DENV), Chikungunya virus (CHIKV) and Zika virus (ZIKV) arboviruses have placed Brazil among the main worldwide endemic areas. Brazilian Northeast region concentrates the highest incidence of infections caused by CHIKV and ZIKV. In Maranhão, the second biggest northeastern state, there are cases of human infections caused by these three arboviruses and presence of Aedes aegypti and Aedes albopictus vectors. In this context, this study aimed to investigate the circulation of CHIKV, DENV and ZIKV in Ae. aegypti and Ae. albopictus mosquitoes collected in urban areas of Barra do Corda, Caxias, Codó, São Luís and São Mateus do Maranhão municipalities in the state of Maranhão through Quantitative Reverse Transcription Polymerase Chain Reaction (RT-qPCR) technique. 428 Ae. aegypti and 1 Ae. albopictus were collected, which formed 44 pools. Three of these showed positive results for CHIKV: AR832767 (five Ae. aegypti female collected in Caxias), AR832784 and AR832785 (both composed of 20 Ae. aegypti female collected in São Mateus do Maranhão). This study consolidates information about CHIKV circulation in state of Maranhão, as well as the role of Ae. aegypti in the transmission of CHIKV in urban area. Copyright © 2018. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Girard, L.; Beutel, J.; Gruber, S.; Hunziker, J.; Lim, R.; Weber, S.
2012-06-01
We present a custom acoustic emission (AE) monitoring system designed to perform long-term measurements on high-alpine rock-walls. AE monitoring is a common technique for characterizing damage evolution in solid materials. The system is based on a two-channel AE sensor node (AE-node) integrated into a Wireless Sensor Network (WSN) customized for operation in harsh environments. This wireless architecture offers flexibility in the deployment of AE-nodes at any position of the rock-wall that needs to be monitored, within a range of a few hundred meters from a core station connected to the internet. The system achieves near real-time data delivery and allows the user to remotely control the AE detection threshold. In order to protect AE sensors and capture acoustic signals from specific depths of the rock-wall, a special casing was developed. The monitoring system is completed by two probes that measure rock temperature and liquid water content, both probes being also integrated into the WSN. We report a first deployment of the monitoring system on a rock-wall at Jungfraujoch, 3500 m a.s.l., Switzerland. While this first deployment of the monitoring system aims to support fundamental research on processes that damage rock under cold climate, the system could serve a number of other applications, including rock-fall hazard surveillance or structural monitoring of concrete structures.
NASA Astrophysics Data System (ADS)
Girard, L.; Beutel, J.; Gruber, S.; Hunziker, J.; Lim, R.; Weber, S.
2012-11-01
We present a custom acoustic emission (AE) monitoring system designed to perform long-term measurements on high-alpine rock walls. AE monitoring is a common technique for characterizing damage evolution in solid materials. The system is based on a two-channel AE sensor node (AE-node) integrated into a wireless sensor network (WSN) customized for operation in harsh environments. This wireless architecture offers flexibility in the deployment of AE-nodes at any position of the rock wall that needs to be monitored, within a range of a few hundred meters from a core station connected to the internet. The system achieves near real-time data delivery and allows the user to remotely control the AE detection threshold. In order to protect AE sensors and capture acoustic signals from specific depths of the rock wall, a special casing was developed. The monitoring system is completed by two probes that measure rock temperature and liquid water content, both probes being also integrated into the WSN. We report a first deployment of the monitoring system on a rock wall at Jungfraujoch, 3500 m a.s.l., Switzerland. While this first deployment of the monitoring system aims to support fundamental research on processes that damage rock under cold climate, the system could serve a number of other applications, including rock fall hazard surveillance or structural monitoring of concrete structures.
The co-movement of monetary policy and its time-varying nature: A DCCA approach
NASA Astrophysics Data System (ADS)
Rohit, Abhishek; Mitra, Subrata Kumar
2018-02-01
Employing a novel methodology of DCCA cross-correlation coefficient (ρDCCA), this study attempts to provide fresh evidences for the co-movement of monetary policies of the advanced (AEs) as well as the emerging economies (EMEs) vis-à-vis the United States. A higher degree of monetary co-movement as measured by ρDCCA values, is identified for the AEs as compared to the EMEs. Lower co-movement of monetary policy is especially noticeable in the short run for EMEs. We further investigate the time-varying nature of such co-movements for the AEs by splitting the period (1980-2014) into four sub periods and also by performing a rolling window estimation for the entire period to reveal smoother dynamics. Significant evidence of higher monetary coordination is revealed for sub-periods with stronger trade and financial linkages.
Lessing, C; Schmitz, A; Schrappe, M
2012-02-01
The Harvard Medical Practice (HMP) Design is based on a multi-staged retrospective review of inpatient records and is used to assess the frequency of (preventable) adverse events ([P]AE) in large study populations. Up to now HMP studies have been conducted in 9 countries. Results differ largely from 2.9% to 3.7% of patients with AE in the USA up to 16.6% in Australia. In our analysis we systematically compare the methodology of 9 HMP studies published in the English language and discuss possible impacts on reported frequencies. Modifications in HMP studies can be individualised from each stage of planning, conducting, and reporting results. In doing so 2 studies from the USA with lowest rates of AE can be characterised by their context of liability and the absence of screening for nosocomial infections. Studies with a high proportion of AE are marked by an intense training of reviewers. Further conclusions are hindered by divergences in defining periods of observation, by presenting frequencies as cumulative prevalences, and differences in the reporting of study results. As a consequence future HMP studies should go for complete, consistent and transparent coverage. Further research should concentrate on advancing methods for collecting data on (P)AE. © Georg Thieme Verlag KG Stuttgart · New York.
NASA Technical Reports Server (NTRS)
Morscher, Gregory; Petko, Jeanne; Kiser, James D.
2002-01-01
Modal acoustic emission (AE) has proven to be an excellent technique to monitor damage accumulation in ceramic matrix composites. In this study, AE was used to monitor tensile load-unload-reload hysteresis tests for a variety of C fiber reinforced, Sic matrix composites. C/SiC composites were reinforced with T-300 and IM7 fibers, had C, multilayer, or pseudo-porous C interphases, and had chemical vapor infiltrated Sic or melt-infiltrated SiC matrices. All of the composites exhibited considerable AE during testing. The extent and nature of the AE activity will be analyzed and discussed in light of matrix cracking and the variety of composite constituents. It is hoped that understanding the nature of stress-dependent damage accumulation in these materials can be of use in life-modeling for these types of composites.
NASA Technical Reports Server (NTRS)
Morscher, Gregory N.; Petko, Jeanne; Kiser, James D.; Gray, Hugh R. (Technical Monitor)
2002-01-01
Modal acoustic emission (AE) has proven to be an excellent technique to monitor damage accumulation in ceramic matrix composites. In this study, AE was used to monitor tensile load-unload-reload hysteresis tests for a variety of C fiber reinforced, SiC matrix composites. C/SiC composites were reinforced with T300 and IM7 fibers, had C, multilayer, or pseudo-porous C interphases, and had chemical vapor infiltrated SiC or melt-infiltrated SiC matrices. All of the composites exhibited considerable AE during testing. The extent and nature of the AE activity will be analyzed and discussed in light of matrix cracking and the variety of composite constituents. It is hoped that understanding the nature of stress dependent damage accumulation in these materials can be of use in life modeling for these types of composites.
Frenel, Jean-Sebastien; Le Tourneau, Christophe; O'Neil, Bert; Ott, Patrick A; Piha-Paul, Sarina A; Gomez-Roca, Carlos; van Brummelen, Emilie M J; Rugo, Hope S; Thomas, Shari; Saraf, Sanatan; Rangwala, Reshma; Varga, Andrea
2017-12-20
Purpose The KEYNOTE-028 trial ( ClinicalTrials.gov identifier: NCT02054806) was designed to assess the safety and efficacy of pembrolizumab in 20 programmed death ligand 1-positive, advanced solid tumor cohorts. Here, we present the results from the cohort of patients with advanced cervical cancer. Methods Patients were treated with pembrolizumab 10 mg/kg every 2 weeks for up to 24 months. Response was assessed every 8 weeks for the first 6 months and every 12 weeks thereafter. The primary end point was overall response rate per Response Evaluation Criteria in Solid Tumors, version 1.1, by investigator review. Safety was a secondary end point. Results Twenty-four patients were enrolled in the cervical cancer cohort. The median age was 42 years (range, 26 to 62 years), 22 patients (92%) had received prior radiation therapy, and 15 patients (63%) had received two or more lines of therapy, including bevacizumab (10 of 24 patients), for advanced disease. At the data cutoff, median follow-up duration was 11.0 months (range, 1.3 to 32.2 months). Overall response rate was 17% (95% CI, 5% to 37%); four patients (17%) achieved a confirmed partial response, and three patients (13%) had stable disease. Median duration of response for the four patients who achieved a partial response was 5.4 months (4.1 to 7.5 months). Treatment related adverse events (AEs) were experienced by 18 patients (75%); only rash (n = 5; 21%) and pyrexia (n = 4; 17%) and occurred in ≥ 10% of patients. Five patients experienced grade 3 treatment-related AEs. No grade 4 treatment-related AEs or deaths were observed. Conclusion In patients with programmed death ligand 1-positive advanced cervical cancer, pembrolizumab demonstrated antitumor activity and exhibited a safety profile consistent with that seen in other tumor types.
Simon, C; Agier, M S; Béné, J; Muller, C; Vrignaud, L; Marret, H; Jonville-Bera, A P
2016-11-01
The aim of the study was to assess the incidence of adverse effects (AE) reported with etonogestrel contraceptive implant in France (Implanon ® and Nexplanon ® ). All cases of AE or unintended pregnancies reported to health authorities or to the firm were analyzed. During 10 years, 5433 AE and 789 unintended pregnancies were reported. Only 388 (7 %) were serious. There were 1137 reports of difficulties to remove, failure to locate or migration, 430 of insertion difficulties and 203 of deformation or expulsion of the implant. Among other AE, the most common were 1694 gynecological AE, 524 skin reactions and 437 metabolic AE. Since the marketing of Nexplanon ® which causes less deep insertions, the incidence of migrations, removal or insertion difficulties has decreased overall (0.92 vs. 1.31/1000 patients), particularly the incidence of removal difficulties, location failures or migrations (0.12 vs 1.01/1000). The infrequent but serious AE were infectious complications at the implant site and pregnancies. When the circumstances of the pregnancy were known, the contraceptive failure was due to the apparent inefficiency of the implant (n=224), to a technique failure (n=203) or to a drug-drug interaction (n=59). This study confirms that AE of this implant are frequent but not serious, except for the pregnancies. The incidence of complications related to insertion decreased with Nexplanon ® . Among other preventable AE, unintended pregnancies due to a drug-drug interaction would require to be better known by the practitioner. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
An AES chip with DPA resistance using hardware-based random order execution
NASA Astrophysics Data System (ADS)
Bo, Yu; Xiangyu, Li; Cong, Chen; Yihe, Sun; Liji, Wu; Xiangmin, Zhang
2012-06-01
This paper presents an AES (advanced encryption standard) chip that combats differential power analysis (DPA) side-channel attack through hardware-based random order execution. Both decryption and encryption procedures of an AES are implemented on the chip. A fine-grained dataflow architecture is proposed, which dynamically exploits intrinsic byte-level independence in the algorithm. A novel circuit called an HMF (Hold-Match-Fetch) unit is proposed for random control, which randomly sets execution orders for concurrent operations. The AES chip was manufactured in SMIC 0.18 μm technology. The average energy for encrypting one group of plain texts (128 bits secrete keys) is 19 nJ. The core area is 0.43 mm2. A sophisticated experimental setup was built to test the DPA resistance. Measurement-based experimental results show that one byte of a secret key cannot be disclosed from our chip under random mode after 64000 power traces were used in the DPA attack. Compared with the corresponding fixed order execution, the hardware based random order execution is improved by at least 21 times the DPA resistance.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Toi, K.; Ogawa, K.; Isobe, M.
2011-01-01
Comprehensive understanding of energetic-ion-driven global instabilities such as Alfven eigenmodes (AEs) and their impact on energetic ions and bulk plasma is crucially important for tokamak and stellarator/helical plasmas and in the future for deuterium-tritium (DT) burning plasma experiments. Various types of global modes and their associated enhanced energetic ion transport are commonly observed in toroidal plasmas. Toroidicity-induced AEs and ellipticity-induced AEs, whose gaps are generated through poloidal mode coupling, are observed in both tokamak and stellarator/helical plasmas. Global AEs and reversed shear AEs, where toroidal couplings are not as dominant were also observed in those plasmas. Helicity induced AEs thatmore » exist only in 3D plasmas are observed in the large helical device (LHD) and Wendelstein 7 Advanced Stellarator plasmas. In addition, the geodesic acoustic mode that comes from plasma compressibility is destabilized by energetic ions in both tokamak and LHD plasmas. Nonlinear interaction of these modes and their influence on the confinement of the bulk plasma as well as energetic ions are observed in both plasmas. In this paper, the similarities and differences in these instabilities and their consequences for tokamak and stellarator/helical plasmas are summarized through comparison with the data sets obtained in LHD. In particular, this paper focuses on the differences caused by the rotational transform profile and the 2D or 3D geometrical structure of the plasma equilibrium. Important issues left for future study are listed.« less
Holubiec, Mariana I; Romero, Juan I; Blanco, Eduardo; Tornatore, Tamara Logica; Suarez, Juan; Rodríguez de Fonseca, Fernando; Galeano, Pablo; Capani, Francisco
2017-07-13
Endocannabinoids (eCBs) and acylethanolamides (AEs) have lately received more attention due to their neuroprotective functions in neurological disorders. Here we analyze the alterations induced by perinatal asphyxia (PA) in the main metabolic enzymes and receptors of the eCBs/AEs in the dorsal striatum of rats. To induce PA, we used a model developed by Bjelke et al. (1991). Immunohistochemical techniques were carried out to determine the expression of neuronal and glial markers (NeuN and GFAP), eCBs/AEs synthesis and degradation enzymes (DAGLα, NAPE-PLD and FAAH) and their receptors (CB1 and PPARα). We found a decrease in NAPE-PLD and PPARα expression. Since NAPE-PLD and PPARα take part in the production and reception of biochemical actions of AEs, such as oleoylethanolamide, these results may suggest that PA plays a key role in the regulation of this system. These data agree with previous results obtained in the hippocampus and encourage us to develop further studies using AEs as potential neuroprotective compounds. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Syed Mazlan, S. M. S.; Abdullah, S. R.; Shahidan, S.; Noor, S. R. Mohd
2017-11-01
Concrete durability may be affected by so many factors such as chemical attack and weathering action that reduce the performance and the service life of concrete structures. Low durability Reinforced concrete (RC) can be greatly improved by using Fiber Reinforce Polymer (FRP). FRP is a commonly used composite material for repairing and strengthening RC structures. A review on application of Acoustic Emission (AE) techniques of real time monitoring for various mechanical tests for RC strengthened with FRP involving four-point bending, three-point bending and cyclic loading was carried out and discussed in this paper. Correlations between each AE analyses namely b-value, sentry and intensity analysis on damage characterization also been critically reviewed. From the review, AE monitoring involving RC strengthened with FRP using b-value, sentry and intensity analysis are proven to be successful and efficient method in determining damage characterization. However, application of AE analysis using sentry analysis is still limited compared to b-value and intensity analysis in characterizing damages especially for RC strengthened with FRP specimen.
Alfven Eigenmode Control in DIII-D
NASA Astrophysics Data System (ADS)
Hu, W.; Olofsson, E.; Welander, A.; van Zeeland, M.; Collins, C.; Heidbrink, W.
2017-10-01
Alfven eigenmodes (AE) driven by fast ions from neutral beam and ion cyclotron heating are common in present day tokamak plasmas and are expected to be destabilized by alpha particles in future burning plasma experiments. Because these waves have been shown to cause loss and redistribution of fast ions which can impact plasma performance and potentially device integrity, developing control techniques for AEs is of paramount importance. In the DIII-D plasma control system, spectral analysis of real-time ECE data is used as a monitor of AE amplitude, frequency, and location. These values are then used for feedback control of the neutral beam power to control Alfven waves and reduce fast ion loss. This work describes tests of AE control experiments in the current ramp up phase, during which multiple Alfven eigenmodes are typically unstable and fast ion confinement is degraded significantly. Comparisons of neutron emission and confined fast ion profiles with and without active AE control will be made. Work supported by the U.S. Dept. of Energy under Award Number DE-FC02-04ER54698.
Analytical methodologies for aluminium speciation in environmental and biological samples--a review.
Bi, S P; Yang, X D; Zhang, F P; Wang, X L; Zou, G W
2001-08-01
It is recognized that aluminium (Al) is a potential environmental hazard. Acidic deposition has been linked to increased Al concentrations in natural waters. Elevated levels of Al might have serious consequences for biological communities. Of particular interest is the speciation of Al in aquatic environments, because Al toxicity depends on its forms and concentrations. In this paper, advances in analytical methodologies for Al speciation in environmental and biological samples during the past five years are reviewed. Concerns about the specific problems of Al speciation and highlights of some important methods are elucidated in sections devoted to hybrid techniques (HPLC or FPLC coupled with ET-AAS, ICP-AES, or ICP-MS), flow-injection analysis (FIA), nuclear magnetic resonance (27Al NMR), electrochemical analysis, and computer simulation. More than 130 references are cited.
Lee, Moon-Soo; Lee, Soyoung I; Hong, Sungdo D; Kim, Ji-Hoon; Choi, Jeewook; Joung, Yoo-Sook
2013-02-01
We explored two different methods of determining adverse events (AEs) among methylphenidate (MPH)-treated adolescents with attention-deficit/hyperactivity disorder (ADHD). We performed a 12-week open label study of osmotic-release oral system (OROS) MPH in adolescents with ADHD who were recruited from four child and adolescent psychiatric outpatient clinics. The AEs were evaluated via a two-step procedure at weeks 1, 3, 6, and 12. The first step was to ask a general question to subjects and their parents regarding AEs. The second step included an AE evaluation process by the investigators, which was performed using a drug-specific checklist. One-way repeated measures ANOVA were used to compare the number of AEs reported by patients and their parents compared with the number reported by clinicians. This statistical technique was also used to compare the number of AEs reported by various sources (i.e., patients, parents, and clinicians) at weeks 1, 3, 6, and 12. Of the 55 participants (43 males, 12 females) between the ages of 12 and 18 enrolled in this study, 47 participants completed the trial. When the number of AEs reported by patients, parents and clinicians were compared, there were no statistically significant differences. When the numbers of AEs obtained from the three different information sources at each study visit were compared, we noted differences. At week 6, the number of AEs evaluated by clinical investigators was higher than those reported by patients and their parents (p=0.003). Although the results did not reach statistical significance, the number of AEs reported by clinical investigators appeared to be greater than those obtained from patients or parents at weeks 3 and 12. The number of AEs reported by patients and their parents were similar at every visit. There were some differences in the pattern of AEs reported between patients and their parents. Clinicians should supplement the subjective report on AEs from patients or their parents with a more drug-specific checklist to obtain drug side effects more effectively. As there are some differences in the pattern of AEs reported by patients and their parents, it is generally recommended that clinicians obtain information from both parties when possible.
Multiplexing Technology for Acoustic Emission Monitoring of Aerospace Vehicles
NASA Technical Reports Server (NTRS)
Prosser, William; Percy, Daniel
2003-01-01
The initiation and propagation of damage mechanisms such as cracks and delaminations generate acoustic waves, which propagate through a structure. These waves can be detected and analyzed to provide the location and severity of damage as part of a structural health monitoring (SHM) system. This methodology of damage detection is commonly known as acoustic emission (AE) monitoring, and is widely used on a variety of applications on civil structures. AE has been widely considered for SHM of aerospace vehicles. Numerous successful ground and flight test demonstrations have been performed, which show the viability of the technology for damage monitoring in aerospace structures. However, one significant current limitation for application of AE techniques on aerospace vehicles is the large size, mass, and power requirements for the necessary monitoring instrumentation. To address this issue, a prototype multiplexing approach has been developed and demonstrated in this study, which reduces the amount of AE monitoring instrumentation required. Typical time division multiplexing techniques that are commonly used to monitor strain, pressure and temperature sensors are not applicable to AE monitoring because of the asynchronous and widely varying rates of AE signal occurrence. Thus, an event based multiplexing technique was developed. In the initial prototype circuit, inputs from eight sensors in a linear array were multiplexed into two data acquisition channels. The multiplexer rapidly switches, in less than one microsecond, allowing the signals from two sensors to be acquired by a digitizer. The two acquired signals are from the sensors on either side of the trigger sensor. This enables the capture of the first arrival of the waves, which cannot be accomplished with the signal from the trigger sensor. The propagation delay to the slightly more distant neighboring sensors makes this possible. The arrival time from this first arrival provides a more accurate source location determination. The multiplexer also identifies which channels are acquired by encoding TTL logic pulses onto the latter portion of the signals. This prototype system was demonstrated using pencil lead break (Hsu-Neilsen) sources on an aluminum plate. It performed as designed providing rapid low noise trigger based switching with encoded channel identification. this multiplexing approach is not limited to linear arrays, but can be easily extended to monitor sensors in planar ot three dimensional arrays. A 32 channel multiplexing system is under development that will allow arbitrary sensor placement. Another benefit of this multiplexing system is the reduction in the expense of data acquisition hardware. In addition, the reduced weight and power requirements are of extreme importance for proposed AE systems on aerospace vehicles.
NASA Astrophysics Data System (ADS)
Schubnel, A. J.; Hilairet, N.; Gasc, J.; Héripré, E.; Brunet, F.; Wang, Y.
2010-12-01
Polycrystalline Mg2GeO4-olivine has been deformed (strain rates from 2.10-4/s to 10-5/s) in the deformation-DIA in 13-BM-D at GSECARS (Advanced Photon Source) at ca. 2 GPa confining pressure for temperatures between 973 and 1573 K (i.e., in the Mg2GeO4-ringwoodite field). Stress, advancement of transformation, and strain were measured in-situ using X-ray diffraction (XRD) and imaging, and acoustic emissions (AE) full waveforms were recorded simultaneously. When differential stress is applied (ca. 1- to 2 GPa) and temperature is increased, the very beginning of the transformation to the ringwoodite structure (as evidenced by in situ XRD) is accompanied by AE bursts which locate within the sample. At high strain rates (>10-4/s) and low temperatures (800-900 degrees C), the number of AEs is comparable, if not larger, to that observed during the cold compression of quartz grains. The largest events always occur at a temperature slightly below that of appearance of the ringwoodite-structure phase on the XRD images patterns. This suggests that AEs are generated while the transition is still nucleation controlled (pseudo-martensitic stage). During stress-relaxation periods, the rate of AE triggering decreases, but does not completely vanish. The AE production rate increases again as soon as deformation is started again. Importantly, we still observed very large AEs at strain rates as low as approx. 10-5/ s. At these early stages of the transformation, the samples did not show any macroscopic rheological weakening. Focal mechanism analysis of the largest AEs showed that they are all of shear type, some being even pure double couple. They radiate about the same amount of energy as typically recorded during fast crack propagation in amorphous glass material. This suggests that they cannot only originate from the martensitic nucleation of oriented spinel-lamellae within a single germanium olivine crystal. Preliminary microstructural analysis (SEM and EBSD) highlights the presence of thin transformation bands made of incoherent spinel micro-grains which, possibly, run across germanium-olivine grain boundaries. These bands are all oriented near perpendicular to the principal compressive stress. Our observations point out that under high deviatoric stress, the olivine - spinel transition is a source of instability which produces micro-sismicity (no AEs were recorded in a similar experiment performed hydrostatically). These instabilities might eventually be precursor to brittle fracturing as observed by Green and Burnley (1989) in their deformation experiments on very similar samples. Both types of study emphasize the potential of phase transitions (with negative volume variations) in triggering brittle failure. Obviously, this has important consequences for the understanding of deep-focus earthquakes occurring in cold and metastable olivine within the transition zone.
NASA Astrophysics Data System (ADS)
Grammatikos, S. A.; Kordatos, E. Z.; Aggelis, D. G.; Matikas, T. E.; Paipetis, A. S.
2012-04-01
Infrared Thermography (IrT) has been shown to be capable of detecting and monitoring service induced damage of repair composite structures. Full-field imaging, along with portability are the primary benefits of the thermographic technique. On-line lock-in thermography has been reported to successfully monitor damage propagation or/and stress concentration in composite coupons, as mechanical stresses in structures induce heat concentration phenomena around flaws. During mechanical fatigue, cyclic loading plays the role of the heating source and this allows for critical and subcritical damage identification and monitoring using thermography. The Electrical Potential Change Technique (EPCT) is a new method for damage identification and monitoring during loading. The measurement of electrical potential changes at specific points of Carbon Fiber Reinforced Polymers (CFRPs) under load are reported to enable the monitoring of strain or/and damage accumulation. Along with the aforementioned techniques Finally, Acoustic Emission (AE) method is well known to provide information about the location and type of damage. Damage accumulation due to cyclic loading imposes differentiation of certain parameters of AE like duration and energy. Within the scope of this study, infrared thermography is employed along with AE and EPCT methods in order to assess the integrity of bonded repair patches on composite substrates and to monitor critical and subcritical damage induced by the mechanical loading. The combined methodologies were effective in identifying damage initiation and propagation of bonded composite repairs.
Vassilopoulos, Dimitrios; Delicha, Evie M; Settas, Loukas; Andrianakos, Alexandros; Aslanidis, Spyros; Boura, Panagiota; Katsounaros, Marios; Athanassiou, Panagiotis; Tempos, Konstantinos; Skarantavos, Grigorios; Antoniadis, Christodoulos; Papazoglou, Sotirios; Sakkas, Lazaros; Galanopoulou, Vassiliki; Skopouli, Fotini; Boki, Kyriaki; Daoussis, Dimitrios; Vritzali, Eleni; Sfikakis, Petros P
2016-01-01
To evaluate the long-term safety of rituximab (RTX) in rheumatoid arthritis (RA) patients in daily clinical practice. This was a multicentre (17 Greek Rheumatology sites), prospective, long-term, pharmacovigilance study of patients with moderate to severe RA and an inadequate response or intolerance to ≥1 anti-tumour necrosis factor (TNF) agents. Adverse events (AEs) were recorded and collected prospectively every 2-6 months. 234 patients (mean age: 59±12.5, 79.5% women, mean DAS28: 5.35±1.32) were included and followed for 27.7 months (median). The overall AEs, serious AE (SAEs) and serious infection (SIEs) rate were 48.36, 6.68 and 2.53/100 patient-years, respectively. Three cases of hepatitis B virus (HBV) reactivation were recorded (two in chronic and one in past HBV infection). Withdrawals due to AEs (5.6%) occurred more frequently during the first cycles of RTX therapy while repeated RTX cycles were not associated with an increased risk of AEs. There were 3 deaths with an incidence rate of 0.69/100 patient-years. Age ≥65 years was associated with a higher incidence rate ratio of AEs and SAEs as compared to <65 years (1.53, p=0.002 and 2.88, p=0.005, respectively). Drug retention rate during 434.28 patient-years of follow-up was 57.3%. Factors associated with drug discontinuation by multivariate analysis included age, baseline swollen joint count and no use of concomitant methotrexate therapy. Long-term RTX therapy in a real-life RA cohort, did not reveal any new safety issues. Advanced age was associated with increased risk of AEs and premature drug discontinuation.
Propulsion Health Monitoring for Enhanced Safety
NASA Technical Reports Server (NTRS)
Butz, Mark G.; Rodriguez, Hector M.
2003-01-01
This report presents the results of the NASA contract Propulsion System Health Management for Enhanced Safety performed by General Electric Aircraft Engines (GE AE), General Electric Global Research (GE GR), and Pennsylvania State University Applied Research Laboratory (PSU ARL) under the NASA Aviation Safety Program. This activity supports the overall goal of enhanced civil aviation safety through a reduction in the occurrence of safety-significant propulsion system malfunctions. Specific objectives are to develop and demonstrate vibration diagnostics techniques for the on-line detection of turbine rotor disk cracks, and model-based fault tolerant control techniques for the prevention and mitigation of in-flight engine shutdown, surge/stall, and flameout events. The disk crack detection work was performed by GE GR which focused on a radial-mode vibration monitoring technique, and PSU ARL which focused on a torsional-mode vibration monitoring technique. GE AE performed the Model-Based Fault Tolerant Control work which focused on the development of analytical techniques for detecting, isolating, and accommodating gas-path faults.
Avionics Architectures for Exploration: Building a Better Approach for (Human) Spaceflight Avionics
NASA Technical Reports Server (NTRS)
Goforth, Montgomery B.; Ratliff, James E.; Hames, Kevin L.; Vitalpur, Sharada V.
2014-01-01
The field of Avionics is advancing far more rapidly in terrestrial applications than in space flight applications. Spaceflight Avionics are not keeping pace with expectations set by terrestrial experience, nor are they keeping pace with the need for increasingly complex automation and crew interfaces as we move beyond Low Earth Orbit. NASA must take advantage of the strides being made by both space-related and terrestrial industries to drive our development and sustaining costs down. This paper describes ongoing efforts by the Avionics Architectures for Exploration (AAE) project chartered by NASA's Advanced Exploration Systems (AES) Program to evaluate new avionic architectures and technologies, provide objective comparisons of them, and mature selected technologies for flight and for use by other AES projects. Results from the AAE project's FY13 efforts are discussed, along with the status of FY14 efforts and future plans.
NASA Technical Reports Server (NTRS)
Haigh, R.; Krimchansky, S. (Technical Monitor)
2000-01-01
This is the Performance Verification Report, METSAT (S/N 108) AMSU-A1 Receiver Assemblies P/N 1356429-1 S/N F05 and P/N 1356409-1 S/N F05, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A). The ATP for the AMSU-A Receiver Subsystem, AE-26002/6A, is prepared to describe in detail the configuration of the test setups and the procedures of the tests to verify that the receiver subsystem meets the specifications as required either in the AMSU-A Instrument Performance and Operation Specifications, S-480-80, or in AMSU-A Receiver Subsystem Specifications, AE-26608, derived by the Aerojet System Engineering. Test results that verify the conformance to the specifications demonstrate the acceptability of that particular receiver subsystem.
NASA Astrophysics Data System (ADS)
Moradian, Zabihallah; Einstein, Herbert H.; Ballivy, Gerard
2016-03-01
Determination of the cracking levels during the crack propagation is one of the key challenges in the field of fracture mechanics of rocks. Acoustic emission (AE) is a technique that has been used to detect cracks as they occur across the specimen. Parametric analysis of AE signals and correlating these parameters (e.g., hits and energy) to stress-strain plots of rocks let us detect cracking levels properly. The number of AE hits is related to the number of cracks, and the AE energy is related to magnitude of the cracking event. For a full understanding of the fracture process in brittle rocks, prismatic specimens of granite containing pre-existing flaws have been tested in uniaxial compression tests, and their cracking process was monitored with both AE and high-speed video imaging. In this paper, the characteristics of the AE parameters and the evolution of cracking sequences are analyzed for every cracking level. Based on micro- and macro-crack damage, a classification of cracking levels is introduced. This classification contains eight stages (1) crack closure, (2) linear elastic deformation, (3) micro-crack initiation (white patch initiation), (4) micro-crack growth (stable crack growth), (5) micro-crack coalescence (macro-crack initiation), (6) macro-crack growth (unstable crack growth), (7) macro-crack coalescence and (8) failure.
Field-Aligned Current at Plasma Sheet Boundary Layers During Storm Time: Cluster Observation
NASA Astrophysics Data System (ADS)
Shi, J.; Cheng, Z.; Zhang, T.; Dunlop, M.; Liu, Z.
2007-05-01
The magnetic field data from the FGM instruments on board the four Cluster spacecrafts were used to study Field Aligned Current (FAC) at the Plasma Sheet Boundary Layers (PSBLs) with the so called "curlometer technique". We analyzed the date obtained in 2001 in the magnetotail and only two cases were found in the storm time. One (August 17, 2001) occurred from sudden commencement to main phase, and the other (October 1, 2001) lay in the main phase and recovery phase. The relationship between the FAC density and the AE index was studied and the results are shown as follows. (1) In the sudden commencement and the main phase the density of the FAC increases obviously, in the recovery phase the density of the FAC increases slightly. (2) From the sudden commencement to the initial stage of the main phase the FAC increases with decreasing AE index and decreases with increasing AE index. From the late stage of the main phase to initial stage of the recovery phase, the FAC increases with increasing AE index and decreases with decreasing AE index. In the late stage of the recovery phase the disturbance of the FAC is not so violent, so that the FAC varying with the AE index is not very obvious.
Dréno, B; Ribas, A; Larkin, J; Ascierto, P A; Hauschild, A; Thomas, L; Grob, J-J; Koralek, D O; Rooney, I; Hsu, J J; McKenna, E F; McArthur, G A
2017-05-01
In the coBRIM phase III trial, the addition of cobimetinib, an MEK inhibitor, to vemurafenib, a BRAF inhibitor, significantly improved progression-free survival [hazard ratio (HR), 0.58; P < 0.0001] and overall survival (HR, 0.70; P = 0.005) in advanced BRAF-mutated melanoma. Here, we report on the incidence, course, and management of key adverse events (AEs) in the coBRIM study. Patients were randomly assigned 1:1 to receive vemurafenib (960 mg twice a day) and either cobimetinib (60 mg once a day, 21 days on/7 days off) or placebo. In addition to standard safety evaluations, patients underwent regular ophthalmic, cardiac, and dermatologic surveillance examinations. Of 495 patients recruited to the study, 493 patients received treatment and constituted the safety population (cobimetinib combined with vemurafenib, 247; vemurafenib, 246). At data cut-off (30 September 2015), median follow-up was 18.5 months. Nearly every patient experienced an AE. In patients who received cobimetinib combined with vemurafenib, the frequency of grade ≥3 AEs was higher than in patients who received vemurafenib alone (75% versus 61%). Most AEs, including grade ≥3 AEs, occurred within the first treatment cycle. After the first cycle (28 days), the incidence of common AEs (rash, diarrhoea, photosensitivity, elevated creatine phosphokinase, serous retinopathy, pyrexia, and liver laboratory abnormalities) decreased substantially over time. Most AEs were managed conservatively by supportive care measures, dose modifications of study treatment, and, occasionally, permanent treatment discontinuation. These data indicate that most AEs arising from treatment with cobimetinib combined with vemurafenib generally occur early in the treatment course, are mild or moderate and are manageable by patient monitoring, dose modification and supportive care. NCT01689519. © The Author 2017. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Goembel, L.
2003-12-01
We are currently developing a flight prototype Spacecraft Charge Monitor (SCM) with support from NASA's Small Business Innovation Research (SBIR) program. The device will use a recently proposed high energy-resolution electron spectroscopic technique to determine spacecraft floating potential. The inspiration for the technique came from data collected by the Atmosphere Explorer (AE) satellites in the 1970s. The data available from the AE satellites indicate that the SCM may be able to determine spacecraft floating potential to within 0.1 V under certain conditions. Such accurate measurement of spacecraft charge could be used to correct biases in space plasma measurements. The device may also be able to measure spacecraft floating potential in the solar wind and in orbit around other planets.
Hydrogen Vent Ground Umbilical Quick Disconnect - Flight Seal Advanced Development
NASA Technical Reports Server (NTRS)
Girard, Doug; Jankowski, Fred; Minich, Mark C.; Yu, Weiping
2012-01-01
This project is a team effort between NASA Engineering (NE) and Team QNA Engineering personnel to provide support for the Umbilical Systems Development project which is funded by Advanced Exploration Systems (AES) and 21st Century Launch Complex. Specifically, this project seeks to develop a new interface between the PPBE baselined Legacy SSP LH2 Vent Arm QD probe and SLS vent seal.
Advanced Solid State Lighting for AES Deep Space Hab Project
NASA Technical Reports Server (NTRS)
Holbert, Eirik
2015-01-01
The advanced Solid State Lighting (SSL) assemblies augmented 2nd generation modules under development for the Advanced Exploration Systems Deep Space Habitat in using color therapy to synchronize crew circadian rhythms. Current RGB LED technology does not produce sufficient brightness to adequately address general lighting in addition to color therapy. The intent is to address both through a mix of white and RGB LEDs designing for fully addressable alertness/relaxation levels as well as more dramatic circadian shifts.
2014-09-18
Converter AES Advance Encryption Standard ANN Artificial Neural Network APS Application Support AUC Area Under the Curve CPA Correlation Power Analysis ...Importance WGN White Gaussian Noise WPAN Wireless Personal Area Networks XEnv Cross-Environment XRx Cross-Receiver xxi ADVANCES IN SCA AND RF-DNA...based tool called KillerBee was released in 2009 that increases the exposure of ZigBee and other IEEE 802.15.4-based Wireless Personal Area Networks
A SOPC-BASED Evaluation of AES for 2.4 GHz Wireless Network
NASA Astrophysics Data System (ADS)
Ken, Cai; Xiaoying, Liang
In modern systems, data security is needed more than ever before and many cryptographic algorithms are utilized for security services. Wireless Sensor Networks (WSN) is an example of such technologies. In this paper an innovative SOPC-based approach for the security services evaluation in WSN is proposed that addresses the issues of scalability, flexible performance, and silicon efficiency for the hardware acceleration of encryption system. The design includes a Nios II processor together with custom designed modules for the Advanced Encryption Standard (AES) which has become the default choice for various security services in numerous applications. The objective of this mechanism is to present an efficient hardware realization of AES using very high speed integrated circuit hardware description language (Verilog HDL) and expand the usability for various applications. As compared to traditional customize processor design, the mechanism provides a very broad range of cost/performance points.
Chung, Sun Ju; Kim, Jong-Min; Kim, Jae Woo; Jeon, Beom Seok; Singh, Pritibha; Thierfelder, Stephan; Ikeda, Junji; Bauer, Lars
2015-05-01
Investigate safety, feasibility and efficacy of switching therapy in patients with advanced-stage Parkinson's disease (PD) inadequately controlled with pramipexole (≤ 3.5 mg/day) or ropinirole (≤ 14 mg/day) to rotigotine transdermal system (≤ 14 mg/24 h; dose adjustments ≤ 16 mg/24 h permitted). PD0009 (ClinicalTrials.gov: NCT01711866) was an open-label study in patients with advanced-stage PD receiving levodopa, and experiencing sleep disturbance or early-morning motor impairment. Pramipexole/ropinirole was switched to equivalent dose rotigotine overnight or in two stages. During the 4-week treatment period rotigotine dose adjustments were permitted (up to 16 mg/24 h). Primary variable: Clinical Global Impressions (CGI) item 4: side effects (assessing safety) at end of treatment. 79/87 (91%) patients completed the study; 2 (2%) withdrew due to adverse events (AEs). Most (84; 97%) had CGI item 4 score < 3 indicating switch did not interfere with functioning; three experienced drug-related AEs interfering with functioning (score = 3). 62% patients improved on Patient Global Impression of Change, assessing effectiveness. AEs occurring ≥ 5%: application site pruritus (10%), application site erythema (7%), dizziness (7%), dyskinesia (7%), erythema (6%), pruritus (6%). Unified Parkinson's Disease Rating Scale II and III, Parkinson's Disease Sleep Scale-2 and Pittsburgh Sleep Quality Index were unchanged. Numerical improvements in 'off' time, awakenings and nocturias were observed. Switch from pramipexole or ropinirole to rotigotine (up to 14 mg/24 h) was feasible and possibly associated with some benefit.
Clark, J A; Klincewicz, S L; Stang, P E
2001-01-01
AE signal detection and its techniques are part of the continuum of public health surveillance, borrowing from both its theory and application (171). Like public health surveillance networks, whose major goals are to identify early signs of new outbreaks, pinpoint new organisms, and monitor designated illnesses, AE signaling and surveillance systems attempt to provide early warnings of previously unsuspected product-AE pairs, hypothesize potential drug-event relations, identify populations "at risk," and facilitate case ascertainment and definition. In both examples, definitive research is often subsequently undertaken to quantify the strength of relations that may be proposed. As with any public health surveillance effort, AE surveillance provides an infrastructure for the ongoing collection of health data and its direct integration into the health regulatory policy (172), including its keystone role in risk assessment and management. However, unlike many surveillance systems, postmarketing AE systems collect case information that is often relatively incomplete and imperfect, estimate exposure based on surrogate values (e.g., sales data), and are used by both governmental and the private sector for preventive planning. These factors make AE signaling and surveillance more ambiguous, regulatory oriented, and complex than its disease counterparts (173). Despite such issues, AE signaling methods continue to evolve in extent, complexity, and acceptance (4, 131, 174). Undoubtedly, this is largely due to the widespread practical experience that has been gained with spontaneous reporting systems over the past 4 decades and the cumulative usefulness that has been demonstrated.
NASA Astrophysics Data System (ADS)
Kwiatek, G.; Plenkers, K.; Zang, A.; Stephansson, O.; Stenberg, L.
2016-12-01
The geothermic Fatigue Hydraulic Fracturing (FHF) in situ experiment (Nova project 54-14-1) took place in the Äspö Hard Rock Laboratory/Sweden in a 1.8 Ma old granitic to dioritic rock mass. The experiment aims at optimizing geothermal heat exchange in crystalline rock mass by multistage hydraulic fracturing at 10 m scale. Six fractures are driven by three different water injection schemes (continuous, cyclic, pulse pressurization) inside a 28 m long, horizontal borehole at depth level 410 m. The rock volume subject to hydraulic fracturing and monitored by three different networks with acoustic emission (AE), micro-seismicity and electromagnetic sensors is about 30 m x 30 m x 30 m in size. The 16-channel In-situ AE monitoring network by GMuG monitored the rupture generation and propagation in the frequency range 1000 Hz to 100,000 Hz corresponding to rupture dimensions from cm- to dm-scale. The in-situ AE monitoring system detected and analyzed AE activity in-situ (P- and S-wave picking, localization). The results were used to review the ongoing microfracturing activity in near real-time. The in-situ AE monitoring network successfully recorded and localized 196 seismic events for most, but not all, hydraulic fractures. All AE events detected in-situ occurred during fracturing time periods. The source parameters (fracture sizes, moment magnitudes, static stress drop) of AE events framing injection periods were calculated using the combined spectral fitting/spectra ratio techniques. The AE activity is clustered in space and clearly outline the fractures location, its orientation, and expansion as well as their temporal evolution. The outward migration of AE events away from the borehole is observed. Fractures extend up to 7 m from the injection interval in the horizontal borehole. The fractures orientation and location correlate for most fractures roughly with the results gained by image packer. Clear differences in seismic response between hydraulic fractures in different formations and injection schemes are visible which need further investigation. For further analysis all AE data of fracturing time periods were recorded continuously with 1 MHz sampling frequency per channel.
Dansin, Eric; Cinieri, Saverio; Garrido, Pilar; Griesinger, Frank; Isla, Dolores; Koehler, Manfred; Kohlhaeufl, Martin
2012-06-01
The clinical benefit and safety profile associated with first-line bevacizumab with doublet chemotherapy in patients with advanced non-squamous non-small cell lung cancer (NSCLC) was established in two large phase III studies, E4599 and AVAiL. SAiL, a single-arm phase IV study, was conducted to evaluate bevacizumab with a range of first-line chemotherapy regimens in a routine oncology practice setting. This analysis of the SAiL data was undertaken to specifically evaluate bleeding adverse events (AEs) in this study, and to explore potential associations between bleeding and baseline patient and disease characteristics. In total, 2212 patients were evaluated. Bleeding AEs (any grade) occurred in 38.2% of patients (grade ≥ 3 bleeding AEs: 3.6%). Grade ≥ 3 pulmonary hemorrhage and central nervous system bleeding events were observed in 0.7% and 0.1% of patients, respectively. The incidence of grade ≥ 3 bleeding AEs was comparable across patient subgroups defined by central tumor location, tumor cavitation, histology, concomitant anticoagulation therapy and age. The majority (88.6%) of bleeding events resolved or improved, 10.2% persisted and 1.3% led to death; 10.2% of bleeding events required bevacizumab interruption or discontinuation. This analysis from the SAiL trial reaffirms a comparable incidence of clinically significant bleeding associated with first-line bevacizumab and chemotherapy as previous phase III studies in NSCLC patients despite less stringent first-line selection criteria. Grade ≥ 3 bleeding appears to be comparable when analyzed for patient and tumor characteristics, including tumor cavitation and concomitant anticoagulation therapy. Most bleeding events resolved or improved, and interruption/discontinuation of bevacizumab was infrequent in a standard oncology practice setting. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Molecular pathophysiology of SLC4 bicarbonate transporters.
Romero, Michael F
2005-09-01
Acid-base (H and HCO3) transport in the kidney is crucial for maintaining blood pH, cellular pH and excreting metabolic acid. HCO3 transport in the kidney is mediated by HCO3 transporter proteins which occur in two gene families in humans, vertebrates and invertebrates (SLC4 and SLC26). Since SLC26 transporters have other, non-HCO3 transport functions, this review highlights the history and recent advances in the SLC4 transporters in the kidney. The SLC4 gene and protein family (10 genes) contains three types of HCO3 transporters: Cl-HCO3 exchangers, Na/HCO3 cotransporters and Na-driven Cl-HCO3 exchangers. Function and human chromosomal location have been determined for most members. Human mutations in AE1 (SLC4A1) and NBCe1 (SLC4A4) are associated with distal and proximal renal tubular acidosis, respectively. Recent advances include the cellular and biophysical mechanisms by which AE1 and NBCe1 mutations lead to renal disease. Mutational and cellular trafficking studies have begun to elucidate the membrane topology and functional domains of AE1 and NBCe1. Knockout mice for AE2 and NBCn1 do not have obvious renal phenotypes. Recently, SLC4A11 (bicarbonate transporter 1) was shown to function as an electrogenic Na/borate cotransporter unable to transport HCO3 but involved in cell cycle control. SLC4 HCO3 transporters play critical roles in systemic and cellular pH homeostasis. Most of the SLC4 members are present at some level in the kidney. Future studies will likely continue to make use of knockout animals, for example mice and zebrafish, human mutations or polymorphisms to elucidate the normal and pathophysiologic roles of these proteins.
Gangadhar, Tara C; Hwu, Wen-Jen; Postow, Michael A; Hamid, Omid; Daud, Adil; Dronca, Roxana; Joseph, Richard; O'Day, Steven J; Hodi, F S; Pavlick, Anna C; Kluger, Harriet; Oxborough, Romina P; Yang, Aiming; Gazdoiu, Mihaela; Kush, Debra A; Ebbinghaus, Scot; Salama, April K S
KEYNOTE-030 (ClinicalTrials.gov ID, NCT02083484) was a global expanded access program that allowed access to pembrolizumab, an antiprogrammed death 1 antibody, for patients with advanced melanoma before its regulatory approval. Patients with unresectable stage III/IV melanoma that progressed after standard-of-care therapy, including ipilimumab and, if BRAF mutant, a BRAF inhibitor, were eligible to receive pembrolizumab 2 mg/kg every 3 weeks. Response was assessed by immune-related response criteria by investigator review. Adverse events (AEs) were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0. In the United States, 979 patients enrolled between April and September 2014. Of the 947 evaluable patients, 621 (65.6%) remained on treatment and transitioned to receive commercial pembrolizumab following approval by the Food and Drug Administration, whereas 326 (34.4%) discontinued, most commonly for disease progression (39.6%) or death (26.4%). Objective response rate was 14.5% (95% confidence interval, 12.2%-16.8%) in the treated population (n=947) and 22.1% (95% confidence interval, 18.8%-25.5%) in patients who had ≥1 response assessment reported (n=619). Twelve patients achieved complete response. One hundred eighty-one (19.1%) patients experienced ≥1 treatment-related AE, most commonly general disorders (8.0%), skin/subcutaneous tissue disorders (7.3%), and gastrointestinal disorders (6.4%); 29 (3.1%) patients experienced ≥1 grade 3/4 treatment-related AE. Immune-mediated AEs were also reported. There were no treatment-related deaths. The safety and efficacy observed in this expanded access program were consistent with those previously reported for similar populations and support the use of pembrolizumab for patients with advanced melanoma.
Kobayashi, Tomoko; Iwama, Shintaro; Yasuda, Yoshinori; Okada, Norio; Tsunekawa, Taku; Onoue, Takeshi; Takagi, Hiroshi; Hagiwara, Daisuke; Ito, Yoshihiro; Morishita, Yoshiaki; Goto, Motomitsu; Suga, Hidetaka; Banno, Ryoichi; Yokota, Kenji; Hase, Tetsunari; Morise, Masahiro; Hashimoto, Naozumi; Ando, Masahiko; Kiyoi, Hitoshi; Gotoh, Momokazu; Ando, Yuichi; Akiyama, Masashi; Hasegawa, Yoshinori; Arima, Hiroshi
2018-03-01
Immune checkpoint inhibitors, including anti-programmed cell death-1 (PD-1) antibodies, have become promising treatments for a variety of advanced malignancies. However, these medicines can cause immune-related adverse events (irAEs), including endocrinopathies. This study examined the incidence of endocrine irAEs induced by nivolumab. Sixty-six patients treated with nivolumab at Nagoya University Hospital were prospectively evaluated for pituitary hormones, thyroid function, antithyroid antibodies (Abs), and glucose levels every 6 weeks after the initiation of nivolumab for 24 weeks. Four out of 66 patients developed destructive thyroiditis, and three patients developed hypothyroidism requiring levothyroxine replacement. The prevalence of positive anti-thyroglobulin Abs (TgAbs) and/or anti-thyroid peroxidase Abs (TPOAbs) at baseline was significantly higher in the group that developed destructive thyroiditis (3/4) compared with the group that did not develop thyroiditis (3/62; P = 0.002). There were no significant differences in other clinical variables between the groups. There were no endocrine irAEs other than destructive thyroiditis during the 24 weeks. The prevalence of TgAbs and/or TPOAbs at baseline was not associated with the development of other irAEs, including pneumonitis, colitis, or skin reactions. Our real-world data showed that destructive thyroiditis was an endocrine irAE that was frequently induced by nivolumab and was significantly associated with positive TgAbs and/or TPOAbs before treatment. Our findings indicate that evaluating these Abs before treatment may help identify patients with a high risk of thyroidal irAEs and may have important clinical benefit.
Development of lightweight structural health monitoring systems for aerospace applications
NASA Astrophysics Data System (ADS)
Pearson, Matthew
This thesis investigates the development of structural health monitoring systems (SHM) for aerospace applications. The work focuses on each aspect of a SHM system covering novel transducer technologies and damage detection techniques to detect and locate damage in metallic and composite structures. Secondly the potential of energy harvesting and power arrangement methodologies to provide a stable power source is assessed. Finally culminating in the realisation of smart SHM structures. 1. Transducer Technology A thorough experimental study of low profile, low weight novel transducers not normally used for acoustic emission (AE) and acousto-ultrasonics (AU) damage detection was conducted. This included assessment of their performance when exposed to aircraft environments and feasibility of embedding these transducers in composites specimens in order to realise smart structures. 2. Damage Detection An extensive experimental programme into damage detection utilising AE and AU were conducted in both composites and metallic structures. These techniques were used to assess different damage mechanism within these materials. The same transducers were used for novel AE location techniques coupled with AU similarity assessment to successfully detect and locate damage in a variety of structures. 3. Energy Harvesting and Power Management Experimental investigations and numerical simulations were undertaken to assess the power generation levels of piezoelectric and thermoelectric generators for typical vibration and temperature differentials which exist in the aerospace environment. Furthermore a power management system was assessed to demonstrate the ability of the system to take the varying nature of the input power and condition it to a stable power source for a system. 4. Smart Structures The research conducted is brought together into a smart carbon fibre wing showcasing the novel embedded transducers for AE and AU damage detection and location, as well as vibration energy harvesting. A study into impact damage detection using the techniques showed the successful detection and location of damage. Also the feasibility of the embedded transducers for power generation was assessed..
Management of adverse events related to new cancer immunotherapy (immune checkpoint inhibitors).
Bourke, Jack M; O'Sullivan, Michael; Khattak, Muhammad A
2016-11-07
New immunotherapies have significantly improved survival in certain advanced cancers in recent years, particularly metastatic melanoma and lung cancer. The most effective of these therapies are the immune checkpoint inhibitors (ICIs) such as ipilimumab, nivolumab and pembrolizumab. The use of ICIs will continue to increase in the coming years as evidence of their benefit in a range of other cancers builds. ICIs are associated with novel immune-related adverse events (irAEs), which can involve a wide range of organs. The most common irAEs involve the skin (rash, pruritus), gastrointestinal tract (diarrhoea, colitis) and endocrine system (thyroid, pituitary). While severity is generally mild, life-threatening complications can occur if not recognised and treated promptly. Due to the diverse manifestations of irAEs, patients may present to doctors who are not familiar with these drugs, which creates the potential for delays in management. Management of irAEs depends on severity and the organ affected. Systemic steroids are often required and ICI therapy may be withheld or discontinued. Additional immunosuppressive medications may be necessary in steroid-refractory cases. This review provides an overview of the potential toxicities and their management for general clinicians. Broader awareness of these issues among medical professionals will hopefully reduce unnecessary delays in diagnosis and treatment. Patient and carer education regarding irAEs is extremely important; patients and carers should be advised to seek urgent medical attention if required.
Gangadari, Bhoopal Rao; Ahamed, Shaik Rafi
2016-12-01
In this paper, we presented a novel approach of low energy consumption architecture of S-Box used in Advanced Encryption Standard (AES) algorithm using programmable second order reversible cellular automata (RCA 2 ). The architecture entails a low power implementation with minimal delay overhead and the performance of proposed RCA 2 based S-Box in terms of security is evaluated using the cryptographic properties such as nonlinearity, correlation immunity bias, strict avalanche criteria, entropy and also found that the proposed architecture is secure enough for cryptographic applications. Moreover, the proposed AES algorithm architecture simulation studies show that energy consumption of 68.726 nJ, power dissipation of 3.856 mW for 0.18- μm at 13.69 MHz and energy consumption of 29.408 nJ, power dissipation of 1.65 mW for 0.13- μm at 13.69 MHz. The proposed AES algorithm with RCA 2 based S-Box shows a reduction power consumption by 50 % and energy consumption by 5 % compared to best classical S-Box and composite field arithmetic based AES algorithm. Apart from that, it is also shown that RCA 2 based S-Boxes are dynamic in nature, invertible, low power dissipation compared to that of LUT based S-Box and hence suitable for Wireless Body Area Network (WBAN) applications.
NASA Astrophysics Data System (ADS)
Gulyaeva, Tamara; Stanislawska, Iwona; Arikan, Feza; Arikan, Orhan
The probability of occurrence of the positive and negative planetary ionosphere storms is evaluated using the W index maps produced from Global Ionospheric Maps of Total Electron Content, GIM-TEC, provided by Jet Propulsion Laboratory, and transformed from geographic coordinates to magnetic coordinates frame. The auroral electrojet AE index and the equatorial disturbance storm time Dst index are investigated as precursors of the global ionosphere storm. The superposed epoch analysis is performed for 77 intense storms (Dst≤-100 nT) and 227 moderate storms (-100
NASA Astrophysics Data System (ADS)
Masera, D.; Bocca, P.; Grazzini, A.
2011-07-01
In this experimental program the main goal is to monitor the damage evolution in masonry and concrete structures by Acoustic Emission (AE) signal analysis applying a well-know seismic method. For this reason the concept of the coda wave interferometry is applied to AE signal recorded during the tests. Acoustic Emission (AE) are very effective non-destructive techniques applied to identify micro and macro-defects and their temporal evolution in several materials. This technique permits to estimate the velocity of ultrasound waves propagation and the amount of energy released during fracture propagation to obtain information on the criticality of the ongoing process. By means of AE monitoring, an experimental analysis on a set of reinforced masonry walls under variable amplitude loading and strengthening reinforced concrete (RC) beams under monotonic static load has been carried out. In the reinforced masonry wall, cyclic fatigue stress has been applied to accelerate the static creep and to forecast the corresponding creep behaviour of masonry under static long-time loading. During the tests, the evaluation of fracture growth is monitored by coda wave interferometry which represents a novel approach in structural monitoring based on AE relative change velocity of coda signal. In general, the sensitivity of coda waves has been used to estimate velocity changes in fault zones, in volcanoes, in a mining environment, and in ultrasound experiments. This method uses multiple scattered waves, which travelled through the material along numerous paths, to infer tiny temporal changes in the wave velocity. The applied method has the potential to be used as a "damage-gauge" for monitoring velocity changes as a sign of damage evolution into masonry and concrete structures.
Physical modeling of the formation and evolution of seismically active fault zones
Ponomarev, A.V.; Zavyalov, A.D.; Smirnov, V.B.; Lockner, D.A.
1997-01-01
Acoustic emission (AE) in rocks is studied as a model of natural seismicity. A special technique for rock loading has been used to help study the processes that control the development of AE during brittle deformation. This technique allows us to extend to hours fault growth which would normally occur very rapidly. In this way, the period of most intense interaction of acoustic events can be studied in detail. Characteristics of the acoustic regime (AR) include the Gutenberg-Richter b-value, spatial distribution of hypocenters with characteristic fractal (correlation) dimension d, Hurst exponent H, and crack concentration parameter Pc. The fractal structure of AR changes with the onset of the drop in differential stress during sample deformation. The change results from the active interaction of microcracks. This transition of the spatial distribution of AE hypocenters is accompanied by a corresponding change in the temporal correlation of events and in the distribution of event amplitudes as signified by a decrease of b-value. The characteristic structure that develops in the low-energy background AE is similar to the sequence of the strongest microfracture events. When the AR fractal structure develops, the variations of d and b are synchronous and d = 3b. This relation which occurs once the fractal structure is formed only holds for average values of d and b. Time variations of d and b are anticorrelated. The degree of temporal correlation of AR has time variations that are similar to d and b variations. The observed variations in laboratory AE experiments are compared with natural seismicity parameters. The close correspondence between laboratory-scale observations and naturally occurring seismicity suggests a possible new approach for understanding the evolution of complex seismicity patterns in nature. ?? 1997 Elsevier Science B.V. All rights reserved.
PERTINENT DRY NEEDLING CONSIDERATIONS FOR MINIMIZING ADVERSE EFFECTS – PART ONE
Halle, Rob J.
2016-01-01
ABSTRACT Background Dry needling is an evidence-based treatment technique that is accepted and used by physical therapists in the United States. This treatment approach focuses on releasing or inactivating muscular trigger points to decrease pain, reduce muscle tension, and assist patients with an accelerated return to active rehabilitation. Issue While commonly used, the technique has some patient risk and value of the treatment should be based on benefit compared to the potential risk. Adverse effects (AEs) with dry needling can be mild or severe, with overall incidence rates varying from zero to rates of approximately 10 percent. While mild AEs are the rule, any procedure that involves a needle insertion has the potential for an AE, with select regions and the underlying anatomy increasing the risk. Known significant AEs from small diameter needle insertion include pneumothorax, cardiac tamponade, hematoma, infection, central nervous system injury, and other complications. Purpose/Objective Underlying anatomy across individuals has variability, requiring an in-depth knowledge of anatomy prior to any needle placement. This commentary is an overview of pertinent anatomy in the region of the thorax, with a ‘part two’ that addresses the abdomen, pelvis, back, vasovagal response, informed consent and other pertinent issues. The purpose of the commentary is to minimize the risk of a dry needling AE. Conclusions/Implications Dry needling is an effective adjunct treatment procedure that is within the recognized scope of physical therapy practice. Physical therapy education and training provides practitioners with the anatomy, basic sciences, and clinical foundation to use this intervention safely and effectively. A safe and evidenced-based implementation of the procedure is based on a thorough understanding of the underlying anatomy and the potential risks, with risks coordinated with patients via informed consent. Levels of Evidence Level 5 PMID:27525188
Knauf, Philip A; Law, Foon-Yee; Leung, Tze-Wah Vivian; Atherton, Stephen J
2004-09-28
Previous fluorescence resonance energy transfer (FRET) measurements, using BIDS (4-benzamido-4'-isothiocyanostilbene-2,2'-disulfonate) as a label for the disulfonic stilbene site and FM (fluorescein-5-maleimide) as a label for the cytoplasmic SH groups on band 3 (AE1), combined with data showing that the cytoplasmic SH groups lie about 40 A from the cytoplasmic surface of the lipid bilayer, would place the BIDS sites very near the membrane's inner surface, a location that seems to be inconsistent with current models of AE1 structure and mechanism. We reinvestigated the BIDS-FM distance, using laser single photon counting techniques as well as steady-state fluorescence of AE1, in its native membrane environment. Both techniques agree that there is very little energy transfer from BIDS to FM. The mean energy transfer (E), based on three-exponential fits to the fluorescence decay data, is 2.5 +/- 0.7% (SEM, N = 12). Steady-state fluorescence measurements also indicate <3% energy transfer from BIDS to FM. These data indicate that the BIDS sites are probably over 63 A from the cytoplasmic SH groups, placing them near the middle or the external half of the lipid bilayer. This relocation of the BIDS sites fits with other evidence that the disulfonic stilbene sites are located farther toward the external membrane surface than Glu-681, a residue near the inner membrane surface whose modification affects the pH dependence and anion selectivity of band 3. The involvement of two relatively distant parts of the AE1 protein in transport function suggests that the transport mechanism requires coordinated large-scale conformational changes in the band 3 protein.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mohd, Shukri; Holford, Karen M.; Pullin, Rhys
2014-02-12
Source location is an important feature of acoustic emission (AE) damage monitoring in nuclear piping. The ability to accurately locate sources can assist in source characterisation and early warning of failure. This paper describe the development of a novelAE source location technique termed 'Wavelet Transform analysis and Modal Location (WTML)' based on Lamb wave theory and time-frequency analysis that can be used for global monitoring of plate like steel structures. Source location was performed on a steel pipe of 1500 mm long and 220 mm outer diameter with nominal thickness of 5 mm under a planar location test setup usingmore » H-N sources. The accuracy of the new technique was compared with other AE source location methods such as the time of arrival (TOA) techniqueand DeltaTlocation. Theresults of the study show that the WTML method produces more accurate location resultscompared with TOA and triple point filtering location methods. The accuracy of the WTML approach is comparable with the deltaT location method but requires no initial acoustic calibration of the structure.« less
Acoustic emission of fire damaged fiber reinforced concrete
NASA Astrophysics Data System (ADS)
Mpalaskas, A. C.; Matikas, T. E.; Aggelis, D. G.
2016-04-01
The mechanical behavior of a fiber-reinforced concrete after extensive thermal damage is studied in this paper. Undulated steel fibers have been used for reinforcement. After being exposed to direct fire action at the temperature of 850°C, specimens were subjected to bending and compression in order to determine the loss of strength and stiffness in comparison to intact specimens and between the two types. The fire damage was assessed using nondestructive evaluation techniques, specifically ultrasonic pulse velocity (UPV) and acoustic emission (AE). Apart from the strong, well known, correlation of UPV to strength (both bending and compressive), AE parameters based mainly on the frequency and duration of the emitted signals after cracking events showed a similar or, in certain cases, better correlation with the mechanical parameters and temperature. This demonstrates the sensitivity of AE to the fracture incidents which eventually lead to failure of the material and it is encouraging for potential in-situ use of the technique, where it could provide indices with additional characterization capability concerning the mechanical performance of concrete after it subjected to fire.
Lin, Chun-Li; Kuo, Wen-Chuan; Yu, Jin-Jie; Huang, Shao-Fu
2013-04-01
CAD/CAM ceramic restorative material is routinely bonded to tooth substrates using adhesive cement. This study investigates micro-crack growth and damage in the ceramic/dentin adhesive interface under fatigue shear testing monitored using the acoustic emission (AE) technique with optical coherence tomography (OCT). Ceramic/dentin adhesive samples were prepared to measure the shear bond strength (SBS) under static load. Fatigue shear testing was performed using a modified ISO14801 method. Loads in the fatigue tests were applied at 80%, 70%, and 60% of the SBS to monitor interface debonding. The AE technique was used to detect micro-crack signals in static and fatigue shear bond tests. The results showed that the average SBS value in the static tests was 10.61±2.23MPa (mean±standard deviation). The average number of fatigue cycles in which ceramic/dentin interface damage was detected in 80%, 70% and 60% of the SBS were 152, 1962 and 9646, respectively. The acoustic behavior varied according to the applied load level. Events were emitted during 60% and 70% fatigue tests. A good correlation was observed between crack location in OCT images and the number of AE signal hits. The AE technique and OCT images employed in this study could potentially be used as a pre-clinical assessment tool to determine the integrity of cemented load bearing restored ceramic material. Sustainable cyclic load stresses in ceramic/dentin-bonded specimens were substantially lower than the measured SBS. Predicted S-N curve showed that the maximum endured load was 4.18MPa passing 10(6) fatigue cyclic. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Lin, Chun-Li; Kuo, Wen-Chuan; Chang, Yen-Hsiang; Yu, Jin-Jie; Lin, Yun-Chu
2014-08-01
This study investigates monitored micro-crack growth and damage in the ceramic/enamel adhesive interface using the acoustic emission (AE) technique with optical coherence tomography (OCT) under fatigue shear testing. Shear bond strength (SBS) was measured first with eight prepared ceramic/enamel adhesive specimens under static loads. The fatigue shear testing was performed with three specimens at each cyclic load according to a modified ISO14801 method, applying at 80%, 75%, 70%, and 65% of the SBS to monitor interface debonding. The number of cycles at each load was recorded until ceramic/enamel adhesive interface debonding occurred. The AE technique was used to detect micro-crack signals in static and fatigue shear bond tests. The results showed that the average SBS value in the static tests was 18.07 ± 1.72 MPa (mean ± standard deviation), expressed in Newton's at 56.77 ± 5.40N. The average number of fatigue cycles in which ceramic/enamel interface damage was detected in 80%, 75%, 70% and 65% of the SBS were 41, 410, 8141 and 76,541, respectively. The acoustic behavior varied according to the applied load level. Events were emitted during 65% and 70% fatigue tests. A good correlation was observed between the crack location in OCT images and the number of AE signal hits. The AE technique combined with OCT images as a pre-clinical assessment tool to determine the integrity of cemented load bearing restored ceramic material. Sustainable cyclic load stresses in ceramic/enamel bonded specimens were substantially lower than the measured SBS. Predicted S-N curve showed that the maximum endured load was 10.98 MPa (about 34.48 N) passing 10(6) fatigue cyclic. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Zhang, Dongjing; Lees, Rosemary Susan; Xi, Zhiyong; Gilles, Jeremie R. L.; Bourtzis, Kostas
2015-01-01
Due to the absence of a perfect method for mosquito sex separation, the combination of the sterile insect technique and the incompatible insect technique is now being considered as a potentially effective method to control Aedes albopictus. In this present study first we examine the minimum pupal irradiation dose required to induce complete sterility in Wolbachia triple-infected (HC), double-infected (GUA) and uninfected (GT) female Ae. albopictus. The HC line is a candidate for Ae. albopictus population suppression programmes, but due to the risk of population replacement which characterizes this triple infected line, the individuals to be released need to be additionally irradiated. After determining the minimum irradiation dose required for complete female sterility, we test whether sterilization is sufficient to prevent invasion of the triple infection from the HC females into double-infected (GUA) populations. Our results indicate that irradiated Ae. albopictus HC, GUA and GT strain females have decreased fecundity and egg hatch rate when irradiated, inversely proportional to the dose, and the complete sterilization of females can be acquired by pupal irradiation with doses above 28 Gy. PCR-based analysis of F1 and F2 progeny indicate that the irradiated HC females, cannot spread the new Wolbachia wPip strain into a small cage GUA population, released at a 1:5 ratio. Considering the above results, we conclude that irradiation can be used to reduce the risk of population replacement caused by an unintentional release of Wolbachia triple-infected Ae. albopictus HC strain females during male release for population suppression. PMID:26252474
Bolann, B J; Rahil-Khazen, R; Henriksen, H; Isrenn, R; Ulvik, R J
2007-01-01
Commonly used techniques for trace-element analysis in human biological material are flame atomic absorption spectrometry (FAAS), graphite furnace atomic absorption spectrometry (GFAAS), inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). Elements that form volatile hydrides, first of all mercury, are analysed by hydride generation techniques. In the absorption techniques the samples are vaporized into free, neutral atoms and illuminated by a light source that emits the atomic spectrum of the element under analysis. The absorbance gives a quantitative measure of the concentration of the element. ICP-AES and ICP-MS are multi-element techniques. In ICP-AES the atoms of the sample are excited by, for example, argon plasma at very high temperatures. The emitted light is directed to a detector, and the optical signals are processed to values for the concentrations of the elements. In ICP-MS a mass spectrometer separates and detects ions produced by the ICP, according to their mass-to-charge ratio. Dilution of biological fluids is commonly needed to reduce the effect of the matrix. Digestion using acids and microwave energy in closed vessels at elevated pressure is often used. Matrix and spectral interferences may cause problems. Precautions should be taken against trace-element contamination during collection, storage and processing of samples. For clinical problems requiring the analysis of only one or a few elements, the use of FAAS may be sufficient, unless the higher sensitivity of GFAAS is required. For screening of multiple elements, however, the ICP techniques are preferable.
A novel dentin bond strength measurement technique using a composite disk in diametral compression.
Huang, Shih-Hao; Lin, Lian-Shan; Rudney, Joel; Jones, Rob; Aparicio, Conrado; Lin, Chun-Pin; Fok, Alex
2012-04-01
New methods are needed that can predict the clinical failure of dental restorations that primarily rely on dentin bonding. Existing methods have shortcomings, e.g. severe deviation in the actual stress distribution from theory and a large standard deviation in the measured bond strength. We introduce here a novel test specimen by examining an endodontic model for dentin bonding. Specifically, we evaluated the feasibility of using the modified Brazilian disk test to measure the post-dentin interfacial bond strength. Four groups of resin composite disks which contained a slice of dentin with or without an intracanal post in the center were tested under diametral compression until fracture. Advanced nondestructive examination and imaging techniques in the form of acoustic emission (AE) and digital image correlation (DIC) were used innovatively to capture the fracture process in real time. DIC showed strain concentration first appearing at one of the lateral sides of the post-dentin interface. The appearance of the interfacial strain concentration also coincided with the first AE signal detected. Utilizing both the experimental data and finite-element analysis, the bond/tensile strengths were calculated to be: 11.2 MPa (fiber posts), 12.9 MPa (metal posts), 8.9 MPa (direct resin fillings) and 82.6 MPa for dentin. We have thus established the feasibility of using the composite disk in diametral compression to measure the bond strength between intracanal posts and dentin. The new method has the advantages of simpler specimen preparation, no premature failure, more consistent failure mode and smaller variations in the calculated bond strength. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Medvedev, Nickolay S.; Shaverina, Anastasiya V.; Tsygankova, Alphiya R.; Saprykin, Anatoly I.
2018-04-01
The paper presents а comparison of analytical performances of inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) for trace analysis of high purity bismuth and bismuth oxide. Matrix effects in the ICP-MS and ICP-AES methods were studied as a function of Bi concentration, ICP power and nebulizer flow rate. For ICP-MS the strong dependence of the matrix effects versus the atomic mass of analytes was observed. For ICP-AES the minimal matrix effects were achieved for spectral lines of analytes with low excitation potentials. The optimum degree of sample dilution providing minimum values of the limits of detection (LODs) was chosen. Both methods let us to reach LODs from n·10-7 to n·10-4 wt% for more than 50 trace elements. For most elements the LODs of ICP-MS were lower in comparison to ICP-AES. Validation of accuracy of the developed techniques was performed by "added-found" experiments and by comparison of the results of ICP-MS and ICP-AES analysis of high-purity bismuth oxide.
NASA Advanced Explorations Systems: 2017 Advancements in Life Support Systems
NASA Technical Reports Server (NTRS)
Schneider, Walter F.; Shull, Sarah A.
2017-01-01
The NASA Advanced Exploration Systems (AES) Life Support Systems (LSS) project strives to develop reliable, energy-efficient, and low-mass spacecraft systems to provide environmental control and life support systems (ECLSS) critical to enabling long duration human missions beyond low Earth orbit (LEO). Highly reliable, closed-loop life support systems are among the capabilities required for the longer duration human space exploration missions planned in the mid-2020s and beyond. The LSS Project is focused on four are-as-architecture and systems engineering for life support systems, environmental monitoring, air revitalization, and wastewater processing and water management. Starting with the International Space Station (ISS) LSS systems as a point of departure where applicable, the three-fold mission of the LSS Project is to address discrete LSS technology gaps, to improve the reliability of LSS systems, and to advance LSS systems toward integrated testing aboard the ISS. This paper is a follow on to the AES LSS development status reported in 2016 and provides additional details on the progress made since that paper was published with specific attention to the status of the Aerosol Sampler ISS Flight Experiment, the Spacecraft Atmosphere Monitor (SAM) Flight Experiment, the Brine Processor Assembly (BPA) Flight Experiment, the CO2 removal technology development tasks, and the work investigating the impacts of dormancy on LSS systems.
[Determination of 24 metal elements and their compounds in air of workplace by ICP-AES].
Wang, Xiang; Qiu, Jianguo; Zhao, Zhonglin; Guo, Ying
2014-06-01
To establish a method for determination of the levels of 24 metal elements and their compounds in the air of workplace by inductively coupled plasma-atomic emission spectroscopy (ICP- AES). Sampling filters were digested by microwave, and diluted to 25 ml. Twenty-four elements (Mg, Ni, K, Mo, Zn, Ca, Ba, Pb, Mn, Cd, Cr, Co, Cu, Sr, Bi, Tl, Sn, Li, Sb, Zr, In, V, Y, and Be) were simultaneously measured by ICP-AES. The detection limits for 24 elements were 0.001∼0.029 mg/L; liner correlation coefficient r values were all equal to or above 0.9994; the relative standard derivations were less than 5%; the recovery rates were 91.2%∼103.9%; the degradation rates in 7 days were less than 9.7%. ICP-AES technique is a simple, rapid, accurate, and reliable method, which can be used to measure 24 metal elements and their compounds in the air of workplace.
NASA Astrophysics Data System (ADS)
Siregar, H.; Junaeti, E.; Hayatno, T.
2017-03-01
Activities correspondence is often used by agencies or companies, so that institutions or companies set up a special division to handle issues related to the letter management. Most of the distribution of letters using electronic media, then the letter should be kept confidential in order to avoid things that are not desirable. Techniques that can be done to meet the security aspect is by using cryptography or by giving a digital signature. The addition of asymmetric and symmetric algorithms, i.e. RSA and AES algorithms, on the digital signature had been done in this study to maintain data security. The RSA algorithm was used during the process of giving digital signature, while the AES algorithm was used during the process of encoding a message that will be sent to the receiver. Based on the research can be concluded that the additions of AES and RSA algorithms on the digital signature meet four objectives of cryptography: Secrecy, Data Integrity, Authentication and Non-repudiation.
Kandile, Nadia G; Mohamed, Mansoura I; Ismaeel, Hind M
2017-12-01
New compounds based on oxindole moiety were synthesized via the reaction of 5-substitued isatins 1a-e with different nucleophiles such as benzidine, 3,3'-dimethoxybenzidine 2a,b and 2,6-diaminopyridine 3 to afford three different classes of bis-Schiff bases 4a-e, 5a-e and 6a-e, respectively. The structures of the new compounds were elucidated on the basis of their FTIR, 1 H NMR, 13 C NMR, GC/MS spectral data and elemental analysis. The in vitro antimicrobial activity of the new compounds was evaluated using a broth dilution technique in terms of minimal inhibitory concentration (MIC) against four bacterial and two fungal pathogens and anticancer activities against HELA cervix. The revealed data showed that compound 9d has excellent activity against Gram + ve and Gram -ve bacteria, and compounds 11b presented promising anticancer activity against HELA cervix. [Formula: see text].
Dermatological adverse events with taxane chemotherapy
Sibaud, Vincent; Lebœuf, Nicole R.; Roche, Henri; Belum, Viswanath R.; Gladieff, Laurence; Deslandres, Marion; Montastruc, Marion; Eche, Audrey; Vigarios, Emmanuelle; Dalenc, Florence; Lacouture, Mario E.
2017-01-01
Taxanes (docetaxel and paclitaxel) are among the most commonly prescribed anticancer drugs approved for the treatment of metastatic or locally advanced breast, non-small cell lung, prostate, gastric, head and neck, and ovarian cancers, as well as in the adjuvant setting for operable node-positive breast cancers. Although the true incidence of dermatological adverse events (AEs) in patients receiving taxanes is not known, and has never been prospectively analysed, they clearly represent one of the major AEs associated with these agents. With an increase in the occurrence of cutaneous AEs during treatment with novel targeted and immunological therapies when used in combination with taxanes, a thorough understanding of reactions attributable to this class is imperative. Moreover, identification and management of dermatological AEs is critical for maintaining the quality of life in cancer patients and for minimizing dose modifications of their antineoplastic regimen. This analysis represents a systematic review of the dermatological conditions reported with the use of these drugs, complemented by experience at comprehensive cancer centres. The conditions reported herein include skin, hair, and nail toxicities. Lastly, we describe the dermatological data available for the new, recently FDA-and EMA- approved, solvent-free nab-paclitaxel. PMID:27550571
Mavrogordato, Mark; Taylor, Mark; Taylor, Andrew; Browne, Martin
2011-05-01
Acoustic emission (AE) is a non-destructive technique that is capable of passively monitoring failure of a construct with excellent temporal resolution. Previous investigations using AE to monitor the integrity of a total hip replacement (THR) have used surface mounted sensors; however, the AE signal attenuates as it travels through materials and across interfaces. This study proposes that directly embedded sensors within the femoral stem of the implant will reduce signal attenuation effects and eliminate potential complications and variability associated with fixing the sensor to the sample. Data was collected during in vitro testing of implanted constructs, and information from both embedded and externally mounted AE sensors was compared and corroborated by micro-Computed Tomography (micro-CT) images taken before and after testing. The results of this study indicate that the embedded sensors gave a closer corroboration to observed damage using micro-CT and were less affected by unwanted noise sources. This has significant implications for the use of AE in assessing the state of THR constructs in vitro and it is hypothesised that directly embedded AE sensors may provide the first steps towards an in vivo, cost effective, user friendly, non-destructive system capable of continuously monitoring the condition of the implanted construct. Copyright © 2010 IPEM. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Dykas, Brian; Harris, James
2017-09-01
Acoustic emission sensing techniques have been applied in recent years to dynamic machinery with varying degrees of success in diagnosing various component faults and distinguishing between operating conditions. This work explores basic properties of acoustic emission signals measured on a small single cylinder diesel engine in a laboratory setting. As reported in other works in the open literature, the measured acoustic emission on the engine is mostly continuous mode and individual burst events are generally not readily identifiable. Therefore, the AE are processed into the local (instantaneous) root mean square (rms) value of the signal which is averaged over many cycles to obtain a mean rms AE in the crank angle domain. Crank-resolved spectral representation of the AE is also given but rigorous investigation of the AE spectral qualities is left to future study. Cycle-to-cycle statistical dispersion of the AE signal is considered to highlight highly variable engine processes. Engine speed was held constant but load conditions are varied to investigate AE signal sensitivity to operating condition. Furthermore, during the course of testing the fuel injector developed a fault and acoustic emission signals were captured and several signal attributes were successful in distinguishing this altered condition. The sampling and use of instantaneous rms acoustic emission signal demonstrated promise for non-intrusive and economical change detection of engine injection, combustion and valve events.
Massard, Christophe; Gordon, Michael S; Sharma, Sunil; Rafii, Saeed; Wainberg, Zev A; Luke, Jason; Curiel, Tyler J; Colon-Otero, Gerardo; Hamid, Omid; Sanborn, Rachel E; O'Donnell, Peter H; Drakaki, Alexandra; Tan, Winston; Kurland, John F; Rebelatto, Marlon C; Jin, Xiaoping; Blake-Haskins, John A; Gupta, Ashok; Segal, Neil H
2016-09-10
To investigate the safety and efficacy of durvalumab, a human monoclonal antibody that binds programmed cell death ligand-1 (PD-L1), and the role of PD-L1 expression on clinical response in patients with advanced urothelial bladder cancer (UBC). A phase 1/2 multicenter, open-label study is being conducted in patients with inoperable or metastatic solid tumors. We report here the results from the UBC expansion cohort. Durvalumab (MEDI4736, 10 mg/kg every 2 weeks) was administered intravenously for up to 12 months. The primary end point was safety, and objective response rate (ORR, confirmed) was a key secondary end point. An exploratory analysis of pretreatment tumor biopsies led to defining PD-L1-positive as ≥ 25% of tumor cells or tumor-infiltrating immune cells expressing membrane PD-L1. A total of 61 patients (40 PD-L1-positive, 21 PD-L1-negative), 93.4% of whom received one or more prior therapies for advanced disease, were treated (median duration of follow-up, 4.3 months). The most common treatment-related adverse events (AEs) of any grade were fatigue (13.1%), diarrhea (9.8%), and decreased appetite (8.2%). Grade 3 treatment-related AEs occurred in three patients (4.9%); there were no treatment-related grade 4 or 5 AEs. One treatment-related AE (acute kidney injury) resulted in treatment discontinuation. The ORR was 31.0% (95% CI, 17.6 to 47.1) in 42 response-evaluable patients, 46.4% (95% CI, 27.5 to 66.1) in the PD-L1-positive subgroup, and 0% (95% CI, 0.0 to 23.2) in the PD-L1-negative subgroup. Responses are ongoing in 12 of 13 responding patients, with median duration of response not yet reached (range, 4.1+ to 49.3+ weeks). Durvalumab demonstrated a manageable safety profile and evidence of meaningful clinical activity in PD-L1-positive patients with UBC, many of whom were heavily pretreated. © 2016 by American Society of Clinical Oncology.
Massard, Christophe; Gordon, Michael S.; Sharma, Sunil; Rafii, Saeed; Wainberg, Zev A.; Luke, Jason; Curiel, Tyler J.; Colon-Otero, Gerardo; Hamid, Omid; Sanborn, Rachel E.; O’Donnell, Peter H.; Drakaki, Alexandra; Tan, Winston; Kurland, John F.; Rebelatto, Marlon C.; Jin, Xiaoping; Blake-Haskins, John A.; Gupta, Ashok
2016-01-01
Purpose To investigate the safety and efficacy of durvalumab, a human monoclonal antibody that binds programmed cell death ligand-1 (PD-L1), and the role of PD-L1 expression on clinical response in patients with advanced urothelial bladder cancer (UBC). Methods A phase 1/2 multicenter, open-label study is being conducted in patients with inoperable or metastatic solid tumors. We report here the results from the UBC expansion cohort. Durvalumab (MEDI4736, 10 mg/kg every 2 weeks) was administered intravenously for up to 12 months. The primary end point was safety, and objective response rate (ORR, confirmed) was a key secondary end point. An exploratory analysis of pretreatment tumor biopsies led to defining PD-L1–positive as ≥ 25% of tumor cells or tumor-infiltrating immune cells expressing membrane PD-L1. Results A total of 61 patients (40 PD-L1–positive, 21 PD-L1–negative), 93.4% of whom received one or more prior therapies for advanced disease, were treated (median duration of follow-up, 4.3 months). The most common treatment-related adverse events (AEs) of any grade were fatigue (13.1%), diarrhea (9.8%), and decreased appetite (8.2%). Grade 3 treatment-related AEs occurred in three patients (4.9%); there were no treatment-related grade 4 or 5 AEs. One treatment-related AE (acute kidney injury) resulted in treatment discontinuation. The ORR was 31.0% (95% CI, 17.6 to 47.1) in 42 response-evaluable patients, 46.4% (95% CI, 27.5 to 66.1) in the PD-L1–positive subgroup, and 0% (95% CI, 0.0 to 23.2) in the PD-L1–negative subgroup. Responses are ongoing in 12 of 13 responding patients, with median duration of response not yet reached (range, 4.1+ to 49.3+ weeks). Conclusion Durvalumab demonstrated a manageable safety profile and evidence of meaningful clinical activity in PD-L1–positive patients with UBC, many of whom were heavily pretreated. PMID:27269937
Smart acoustic emission system for wireless monitoring of concrete structures
NASA Astrophysics Data System (ADS)
Yoon, Dong-Jin; Kim, Young-Gil; Kim, Chi-Yeop; Seo, Dae-Cheol
2008-03-01
Acoustic emission (AE) has emerged as a powerful nondestructive tool to detect preexisting defects or to characterize failure mechanisms. Recently, this technique or this kind of principle, that is an in-situ monitoring of inside damages of materials or structures, becomes increasingly popular for monitoring the integrity of large structures. Concrete is one of the most widely used materials for constructing civil structures. In the nondestructive evaluation point of view, a lot of AE signals are generated in concrete structures under loading whether the crack development is active or not. Also, it was required to find a symptom of damage propagation before catastrophic failure through a continuous monitoring. Therefore we have done a practical study in this work to fabricate compact wireless AE sensor and to develop diagnosis system. First, this study aims to identify the differences of AE event patterns caused by both real damage sources and the other normal sources. Secondly, it was focused to develop acoustic emission diagnosis system for assessing the deterioration of concrete structures such as a bridge, dame, building slab, tunnel etc. Thirdly, the wireless acoustic emission system was developed for the application of monitoring concrete structures. From the previous laboratory study such as AE event patterns analysis under various loading conditions, we confirmed that AE analysis provided a promising approach for estimating the condition of damage and distress in concrete structures. In this work, the algorithm for determining the damage status of concrete structures was developed and typical criteria for decision making was also suggested. For the future application of wireless monitoring, a low energy consumable, compact, and robust wireless acoustic emission sensor module was developed and applied to the concrete beam for performance test. Finally, based on the self-developed diagnosis algorithm and compact wireless AE sensor, new AE system for practical AE diagnosis was demonstrated for assessing the conditions of damage and distress in concrete structures.
Sawa, Mariko; Yabuki, Akira; Kohyama, Moeko; Miyoshi, Noriaki; Yamato, Osamu
2018-06-01
Immunocytochemistry (ICC) is utilized as an advanced technique in veterinary cytology. In tumor diagnosis, cytokeratin and vimentin are markers used to distinguish the origin of tumor cells. Standard enzyme-based ICC has limitations in clinical use; and therefore, more convenient and reliable methods are needed. The purpose of this study was to develop a rapid multiple immunofluorescent (RMIF) detection method for dual cytokeratin and vimentin staining on cytology slides in dogs. Air-dried smear samples from solid tumors and sediments of pleural effusions were prepared from dogs (n = 14) that were admitted to the Veterinary Teaching Hospital, Kagoshima University, Japan. Mouse monoclonal anti-human cytokeratin (AE1/AE3) and rabbit monoclonal anti-human vimentin (SP20) antibodies were used as primary antibodies, followed by staining with Alexa Fluor-conjugated secondary antibodies. Staining using the RMIF method was compared with enzyme-based ICC staining. Rapid multiple immunofluorescent immunostaining was clear and specific in the evaluated smears, whereas the enzyme-based ICC showed nonspecific signals. By using the RMIF staining method, epithelial cells, mesenchymal cells, and mesothelial cells could be classified on a single smear of a pleural effusion. In smears of lymph nodes with epithelial tumor metastases, the RMIF method successfully detected metastatic epithelial tumor cells. The RMIF method might be a useful tool for diagnostic cytology in veterinary medicine. © 2018 American Society for Veterinary Clinical Pathology.
Using Carbohydrate Interaction Assays to Reveal Novel Binding Sites in Carbohydrate Active Enzymes.
Cockburn, Darrell; Wilkens, Casper; Dilokpimol, Adiphol; Nakai, Hiroyuki; Lewińska, Anna; Abou Hachem, Maher; Svensson, Birte
2016-01-01
Carbohydrate active enzymes often contain auxiliary binding sites located either on independent domains termed carbohydrate binding modules (CBMs) or as so-called surface binding sites (SBSs) on the catalytic module at a certain distance from the active site. The SBSs are usually critical for the activity of their cognate enzyme, though they are not readily detected in the sequence of a protein, but normally require a crystal structure of a complex for their identification. A variety of methods, including affinity electrophoresis (AE), insoluble polysaccharide pulldown (IPP) and surface plasmon resonance (SPR) have been used to study auxiliary binding sites. These techniques are complementary as AE allows monitoring of binding to soluble polysaccharides, IPP to insoluble polysaccharides and SPR to oligosaccharides. Here we show that these methods are useful not only for analyzing known binding sites, but also for identifying new ones, even without structural data available. We further verify the chosen assays discriminate between known SBS/CBM containing enzymes and negative controls. Altogether 35 enzymes are screened for the presence of SBSs or CBMs and several novel binding sites are identified, including the first SBS ever reported in a cellulase. This work demonstrates that combinations of these methods can be used as a part of routine enzyme characterization to identify new binding sites and advance the study of SBSs and CBMs, allowing them to be detected in the absence of structural data.
Using Carbohydrate Interaction Assays to Reveal Novel Binding Sites in Carbohydrate Active Enzymes
Wilkens, Casper; Dilokpimol, Adiphol; Nakai, Hiroyuki; Lewińska, Anna; Abou Hachem, Maher; Svensson, Birte
2016-01-01
Carbohydrate active enzymes often contain auxiliary binding sites located either on independent domains termed carbohydrate binding modules (CBMs) or as so-called surface binding sites (SBSs) on the catalytic module at a certain distance from the active site. The SBSs are usually critical for the activity of their cognate enzyme, though they are not readily detected in the sequence of a protein, but normally require a crystal structure of a complex for their identification. A variety of methods, including affinity electrophoresis (AE), insoluble polysaccharide pulldown (IPP) and surface plasmon resonance (SPR) have been used to study auxiliary binding sites. These techniques are complementary as AE allows monitoring of binding to soluble polysaccharides, IPP to insoluble polysaccharides and SPR to oligosaccharides. Here we show that these methods are useful not only for analyzing known binding sites, but also for identifying new ones, even without structural data available. We further verify the chosen assays discriminate between known SBS/CBM containing enzymes and negative controls. Altogether 35 enzymes are screened for the presence of SBSs or CBMs and several novel binding sites are identified, including the first SBS ever reported in a cellulase. This work demonstrates that combinations of these methods can be used as a part of routine enzyme characterization to identify new binding sites and advance the study of SBSs and CBMs, allowing them to be detected in the absence of structural data. PMID:27504624
Bioavailability of particle-associated Se to the bivalve Potamocorbula amurensis
Schlekat, C.E.; Dowdle, P.R.; Lee, B.-G.; Luoma, S.N.; Oremland, R.S.
2000-01-01
Elemental selenium, Se(0), is a prevalent chemical form in sediments, but little is known about its bioavailability. We evaluated the bioavailability of two forms of Se(0) by generating radioisotopic 75Se(0) through bacterial dissimilatory reduction of 75SeO32- by pure bacterial cultures (SES) and by an anaerobic sediment microbial consortium (SED). A third form was generated by reducing 75SeO32- with ascorbic acid (AA). Speciation determinations showed that AA and SES were >90% Se(0), but SED showed a mixture of Se(0), selenoanions, and a residual fraction. Pulse-chase techniques were used to measure assimilation efficiencies (AE) of these particulate Se forms by the bivalve Potamocorbula amurensis. Mean AE values were 3 ?? 2% for AA, 7 ?? 1% for SES, and 28 ?? 15% for SED, showing that the bioavailability of reduced, particle-associated Se is dependent upon its origin. To determine if oxidative microbial processes increased Se transfer, SES 75Se(0) was incubated with an aerobic sediment microbial consortium. After 113 d of incubation, 36% of SES Se(0) was oxidized to SeO32-. Assimilation of total particulate Se was unaffected however (mean AE = 5.5%). The mean AE from the diatom Phaeodactylum tricornutum was 58 ?? 8%, verifying the importance of Se associated with biogenic particles. Speciation and AE results from SED suggest that selenoanion reduction in wetlands and estuaries produces biologically available reduced selenium.Elemental selenium, Se(0), is a prevalent chemical form in sediments, but little is known about its bioavailability. We evaluated the bioavailability of two forms of Se(0) by generating radioisotopic 75Se(0) through bacterial dissimilatory reduction of 75SeO32- by pure bacterial cultures (SES) and by an anaerobic sediment microbial consortium (SED). A third form was generated by reducing 75SeO32 with ascorbic acid (AA). Speciation determinations showed that AA and SES were > 90% Se(0), but SED showed a mixture of Se(0), selenoanions, and a residual fraction. Pulse-chase techniques were used to measure assimilation efficiencies (AE) of these particulate Se forms by the bivalve Potamocorbula amurensis. Mean AE values were 3 ?? 2% for AA, 7 ?? 1% for SES, and 28 ?? 15% for SED, showing that the bioavailability of reduced, particle-associated Se is dependent upon its origin. To determine if oxidative microbial processes increased Se transfer, SES 75Se(0) was incubated with an aerobic sediment microbial consortium. After 113 d of incubation, 36% of SES Se(0) was oxidized to SeO32-. Assimilation of total particulate Se was unaffected however (mean AE = 5.5%). The mean AE from the diatom Phaeodactylum tricornutum was 58 ?? 8%, verifying the importance of Se associated with biogenic particles. Speciation and AE results from SED suggest that selenoanion reduction in wetlands and estuaries produces biologically available reduced selenium.
NASA Astrophysics Data System (ADS)
López-Comino, J. A.; Cesca, S.; Heimann, S.; Grigoli, F.; Milkereit, C.; Dahm, T.; Zang, A.
2017-11-01
A crucial issue to characterize hydraulic fractures is the robust, accurate and automated detection and location of acoustic emissions (AE) associated with the fracture nucleation and growth process. Waveform stacking and coherence analysis techniques are here adapted using massive datasets with very high sampling (1 MHz) from a hydraulic fracturing experiment that took place 410 m below surface in the Äspö Hard Rock Laboratory (Sweden). We present the results obtained during the conventional, continuous water injection experiment Hydraulic Fracture 2. The resulting catalogue is composed of more than 4000 AEs. Frequency-magnitude distribution from AE magnitudes (MAE) reveals a high b value of 2.4. The magnitude of completeness is also estimated approximately MAE 1.1, and we observe an interval range of MAE between 0.77 and 2.79. The hydraulic fractures growth is then characterized by mapping the spatiotemporal evolution of AE hypocentres. The AE activity is spatially clustered in a prolate ellipsoid, resembling the main activated fracture volume ( 105 m3), where the lengths of the principal axes ( a = 10 m; b = 5 m; c = 4 m) define its size and its orientation can be estimated for a rupture plane (strike 123°, dip 60°). An asymmetric rupture process regarding to the fracturing borehole is clearly exhibited. AE events migrate upwards covering the depth interval between 404 and 414 m. After completing each injection and reinjection phase, the AE activity decreases and appears located in the same area of the initial fracture phase, suggesting a crack-closing effect.
Nivolumab Monotherapy for First-Line Treatment of Advanced Non–Small-Cell Lung Cancer
Rizvi, Naiyer A.; Chow, Laura Q.; Borghaei, Hossein; Brahmer, Julie; Ready, Neal; Gerber, David E.; Shepherd, Frances A.; Antonia, Scott; Goldman, Jonathan W.; Juergens, Rosalyn A.; Laurie, Scott A.; Nathan, Faith E.; Shen, Yun; Harbison, Christopher T.; Hellmann, Matthew D.
2016-01-01
Purpose Nivolumab, a programmed death-1 (PD-1) immune checkpoint inhibitor antibody, has demonstrated improved survival over docetaxel in previously treated advanced non–small-cell lung cancer (NSCLC). First-line monotherapy with nivolumab for advanced NSCLC was evaluated in the phase I, multicohort, Checkmate 012 trial. Methods Fifty-two patients received nivolumab 3 mg/kg intravenously every 2 weeks until progression or unacceptable toxicity; postprogression treatment was permitted per protocol. The primary objective was to assess safety; secondary objectives included objective response rate (ORR) and 24-week progression-free survival (PFS) rate; overall survival (OS) was an exploratory end point. Results Any-grade treatment-related adverse events (AEs) occurred in 71% of patients, most commonly: fatigue (29%), rash (19%), nausea (14%), diarrhea (12%), pruritus (12%), and arthralgia (10%). Ten patients (19%) reported grade 3 to 4 treatment-related AEs; grade 3 rash was the only grade 3 to 4 event occurring in more than one patient (n = 2; 4%). Six patients (12%) discontinued because of a treatment-related AE. The confirmed ORR was 23% (12 of 52), including four ongoing complete responses. Nine of 12 responses (75%) occurred by first tumor assessment (week 11); eight (67%) were ongoing (range, 5.3+ to 25.8+ months) at the time of data lock. ORR was 28% (nine of 32) in patients with any degree of tumor PD–ligand 1 expression and 14% (two of 14) in patients with no PD–ligand 1 expression. Median PFS was 3.6 months, and the 24-week PFS rate was 41% (95% CI, 27 to 54). Median OS was 19.4 months, and the 1-year and 18-month OS rates were 73% (95% CI, 59 to 83) and 57% (95% CI, 42 to 70), respectively. Conclusion First-line nivolumab monotherapy demonstrated a tolerable safety profile and durable responses in first-line advanced NSCLC. PMID:27354485
Nivolumab Monotherapy for First-Line Treatment of Advanced Non-Small-Cell Lung Cancer.
Gettinger, Scott; Rizvi, Naiyer A; Chow, Laura Q; Borghaei, Hossein; Brahmer, Julie; Ready, Neal; Gerber, David E; Shepherd, Frances A; Antonia, Scott; Goldman, Jonathan W; Juergens, Rosalyn A; Laurie, Scott A; Nathan, Faith E; Shen, Yun; Harbison, Christopher T; Hellmann, Matthew D
2016-09-01
Nivolumab, a programmed death-1 (PD-1) immune checkpoint inhibitor antibody, has demonstrated improved survival over docetaxel in previously treated advanced non-small-cell lung cancer (NSCLC). First-line monotherapy with nivolumab for advanced NSCLC was evaluated in the phase I, multicohort, Checkmate 012 trial. Fifty-two patients received nivolumab 3 mg/kg intravenously every 2 weeks until progression or unacceptable toxicity; postprogression treatment was permitted per protocol. The primary objective was to assess safety; secondary objectives included objective response rate (ORR) and 24-week progression-free survival (PFS) rate; overall survival (OS) was an exploratory end point. Any-grade treatment-related adverse events (AEs) occurred in 71% of patients, most commonly: fatigue (29%), rash (19%), nausea (14%), diarrhea (12%), pruritus (12%), and arthralgia (10%). Ten patients (19%) reported grade 3 to 4 treatment-related AEs; grade 3 rash was the only grade 3 to 4 event occurring in more than one patient (n = 2; 4%). Six patients (12%) discontinued because of a treatment-related AE. The confirmed ORR was 23% (12 of 52), including four ongoing complete responses. Nine of 12 responses (75%) occurred by first tumor assessment (week 11); eight (67%) were ongoing (range, 5.3+ to 25.8+ months) at the time of data lock. ORR was 28% (nine of 32) in patients with any degree of tumor PD-ligand 1 expression and 14% (two of 14) in patients with no PD-ligand 1 expression. Median PFS was 3.6 months, and the 24-week PFS rate was 41% (95% CI, 27 to 54). Median OS was 19.4 months, and the 1-year and 18-month OS rates were 73% (95% CI, 59 to 83) and 57% (95% CI, 42 to 70), respectively. First-line nivolumab monotherapy demonstrated a tolerable safety profile and durable responses in first-line advanced NSCLC. © 2016 by American Society of Clinical Oncology.
Non-destructive bridge testing with advanced micro-II digital AE system.
DOT National Transportation Integrated Search
2011-02-02
The proposed research at the Coast Guard Blvd. in the City of Portsmouth was completed according to the plan of action prepared in consultation with the VDOT and the Virginia Council of Transportation Innovation and Research (VCTIR). The major elemen...
NASA Technical Reports Server (NTRS)
Knox, James C.; Stanley, Christine M.
2015-01-01
The Life Support Systems Project (LSSP) under the Advanced Exploration Systems (AES) program builds upon the work performed under the AES Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project focusing on the numerous technology development areas. The Carbon Dioxide (CO2) removal and associated air drying development efforts are focused on improving the current state-of-the-art system on the International Space Station (ISS) utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. A component of the CO2 removal effort utilizes a virtual Carbon Dioxide Removal Assembly, revision 4 (CDRA-4) test bed to test a large number of potential operational configurations with independent variations in flow rate, cycle time, heater ramp rate, and set point. Initial ground testing will provide prerequisite source data and provide baseline data in support of the virtual CDRA. Once the configurations with the highest performance and lowest power requirements are determined by the virtual CDRA, the results will be confirmed by testing these configurations with the CDRA-4EU ground test hardware. This paper describes the initial ground testing of select configurations. The development of the virtual CDRA under the AES-LSS Project will be discussed in a companion paper.
Advanced Solid State Lighting for Human Evaluation Project
NASA Technical Reports Server (NTRS)
Zeitlin, Nancy; Holbert, Eirik
2015-01-01
Lighting intensity and color have a significant impact on human circadian rhythms. Advanced solid state lighting was developed for the Advanced Exploration System (AES) Deep Space Habitat(DSH) concept demonstrator. The latest generation of assemblies using the latest commercially available LED lights were designed for use in the Bigelow Aerospace Environmental Control and Life Support System (ECLSS) simulator and the University of Hawaii's Hawaii Space Exploration Analog and Simulation (Hi-SEAS) habitat. Agreements with both these organizations will allow the government to receive feedback on the lights and lighting algorithms from long term human interaction.
Piwko, Charles; Prady, Catherine; Yunger, Simon; Pollex, Erika; Moser, Aurelie
2015-08-01
Trastuzumab emtansine (T-DM1, KADCYLA(®)) is an antibody-drug conjugate comprised of the cytotoxic agent DM1 and trastuzumab (HERCEPTIN(®)). The safety profile of T-DM1 in human epidermal growth factor receptor 2 (HER2)-positive locally advanced or metastatic breast cancer previously treated with trastuzumab and a taxane was investigated in the phase III EMILIA trial. The trial demonstrated clinically and statistically meaningful differences in the safety profile between T-DM1 and capecitabine plus lapatinib (CAP + LAP). The objective of this study was to estimate the costs of managing treatment-related grade ≥ 3 adverse events (AEs) that occurred in ≥ 2% of patients and grade 2 AEs that occurred in ≥ 5% of patients taking T-DM1 compared with patients taking CAP + LAP based on the EMILIA trial, from the perspective of Canadian public payers. An Excel-based model was utilized to estimate the relevant costs. Clinical data were obtained from the EMILIA trial. Cost information was obtained from the literature, clinical experts, and standard cost sources. The analysis was conducted from the Canadian public-payer perspective and reported in 2014 Canadian dollars (CAD). The management of included treatment-related AEs resulted in higher estimated per-patient costs of CAD6901 for CAP + LAP versus CAD3380 for T-DM1, resulting in savings of CAD3521. From a Canadian perspective, this analysis demonstrated that utilizing T-DM1 for the management of HER2-positive metastatic breast cancer results in substantial savings to the public health-care system when considering the costs of treatment-related AEs, due to fewer amount of toxicities compared with CAP + LAP. Results of various sensitivity analyses investigating changes in number and costs of AEs confirmed the findings; however, the magnitude of cost savings varied. Further analyses are necessary to determine whether these cost savings would occur in other countries and health-care systems.
Single-crystal silicon trench etching for fabrication of highly integrated circuits
NASA Astrophysics Data System (ADS)
Engelhardt, Manfred
1991-03-01
The development of single crystal silicon trench etching for fabrication of memory cells in 4 16 and 64Mbit DRAMs is reviewed in this paper. A variety of both etch tools and process gases used for the process development is discussed since both equipment and etch chemistry had to be improved and changed respectively to meet the increasing requirements for high fidelity pattern transfer with increasing degree of integration. In additon to DRAM cell structures etch results for deep trench isolation in advanced bipolar ICs and ASICs are presented for these applications grooves were etched into silicon through a highly doped buried layer and at the borderline of adjacent p- and n-well areas respectively. Shallow trench etching of large and small exposed areas with identical etch rates is presented as an approach to replace standard LOCOS isolation by an advanced isolation technique. The etch profiles were investigated with SEM TEM and AES to get information on contathination and damage levels and on the mechanism leading to anisotropy in the dry etch process. Thermal wave measurements were performed on processed single crystal silicon substrates for a fast evaluation of the process with respect to plasma-induced substrate degradation. This useful technique allows an optimization ofthe etch process regarding high electrical performance of the fully processed memory chip. The benefits of the use of magnetic fields for the development of innovative single crystal silicon dry
Kobayashi, Tomoko; Iwama, Shintaro; Yasuda, Yoshinori; Okada, Norio; Tsunekawa, Taku; Onoue, Takeshi; Takagi, Hiroshi; Hagiwara, Daisuke; Ito, Yoshihiro; Morishita, Yoshiaki; Goto, Motomitsu; Suga, Hidetaka; Banno, Ryoichi; Yokota, Kenji; Hase, Tetsunari; Morise, Masahiro; Hashimoto, Naozumi; Ando, Masahiko; Kiyoi, Hitoshi; Gotoh, Momokazu; Ando, Yuichi; Akiyama, Masashi; Hasegawa, Yoshinori; Arima, Hiroshi
2018-01-01
Abstract Context Immune checkpoint inhibitors, including anti–programmed cell death-1 (PD-1) antibodies, have become promising treatments for a variety of advanced malignancies. However, these medicines can cause immune-related adverse events (irAEs), including endocrinopathies. Objective This study examined the incidence of endocrine irAEs induced by nivolumab. Patients and Main Outcome Measured Sixty-six patients treated with nivolumab at Nagoya University Hospital were prospectively evaluated for pituitary hormones, thyroid function, antithyroid antibodies (Abs), and glucose levels every 6 weeks after the initiation of nivolumab for 24 weeks. Results Four out of 66 patients developed destructive thyroiditis, and three patients developed hypothyroidism requiring levothyroxine replacement. The prevalence of positive anti-thyroglobulin Abs (TgAbs) and/or anti–thyroid peroxidase Abs (TPOAbs) at baseline was significantly higher in the group that developed destructive thyroiditis (3/4) compared with the group that did not develop thyroiditis (3/62; P = 0.002). There were no significant differences in other clinical variables between the groups. There were no endocrine irAEs other than destructive thyroiditis during the 24 weeks. The prevalence of TgAbs and/or TPOAbs at baseline was not associated with the development of other irAEs, including pneumonitis, colitis, or skin reactions. Conclusions Our real-world data showed that destructive thyroiditis was an endocrine irAE that was frequently induced by nivolumab and was significantly associated with positive TgAbs and/or TPOAbs before treatment. Our findings indicate that evaluating these Abs before treatment may help identify patients with a high risk of thyroidal irAEs and may have important clinical benefit. PMID:29600292
Kobayashi, Haruki; Naito, Tateaki; Omae, Katsuhiro; Omori, Shota; Nakashima, Kazuhisa; Wakuda, Kazushige; Ono, Akira; Kenmotsu, Hirotsugu; Murakami, Haruyasu; Endo, Masahiro; Takahashi, Toshiaki
2018-07-01
Patients with advanced non-small cell lung cancer (NSCLC) and interstitial lung disease (ILD) are commonly excluded from most clinical trials because of acute exacerbation (AE) of ILD triggered by chemotherapy. Data on the efficacy and feasibility of chemotherapy are limited in this patient population. Recently, the ILD-GAP index and staging system was reported as a clinical prognostic factor associated with mortality in patients with ILD. Therefore, we evaluated the incidence of ILD-AE during the surveillance term in this study and the prognosis in patients with NSCLC and ILD using a modified ILD-GAP (ILD-NSCLC-GAP) index scoring system. The medical records of patients with NSCLC and ILD who underwent a pulmonary function test before initiation of platinum-based chemotherapy as first-line treatment at the Shizuoka Cancer Center between September 2002 and December 2014 were reviewed retrospectively. Among these patients, we compared the incidence of ILD-AE, one-year survival rate, and overall survival (OS) between the ILD-NSCLC-GAP index scores and stages. Of the 78 patients included, 21 (27%; 95% confidence interval [CI], 18%-38%) had ILD-AE during the surveillance term in this study. The one-year survival and median OS rates were 49% and 11.3 months, respectively. The incidence of ILD-AE increased gradually and the one-year survival and median OS rates decreased gradually with increasing ILD-NSCLC-GAP index scores and stages. The ILD-NSCLC-GAP index scoring and staging system may be a useful tool to calculate a prediction of the incidence of ILD-AE and its prognosis for patients with NSCLC and ILD. Copyright © 2018 Elsevier B.V. All rights reserved.
Electron spectroscopy analysis
NASA Technical Reports Server (NTRS)
Gregory, John C.
1992-01-01
The Surface Science Laboratories at the University of Alabama in Huntsville (UAH) are equipped with x-ray photoelectron spectroscopy (XPS or ESCA) and Auger electron spectroscopy (AES) facilities. These techniques provide information from the uppermost atomic layers of a sample, and are thus truly surface sensitive. XPS provides both elemental and chemical state information without restriction on the type of material that can be analyzed. The sample is placed into an ultra high vacuum (UHV) chamber and irradiated with x-rays which cause the ejection of photoelectrons from the sample surface. Since x-rays do not normally cause charging problems or beam damage, XPS is applicable to a wide range of samples including metals, polymers, catalysts, and fibers. AES uses a beam of high energy electrons as a surface probe. Following electronic rearrangements within excited atoms by this probe, Auger electrons characteristic of each element present are emitted from the sample. The main advantage of electron induced AES is that the electron beam can be focused down to a small diameter and localized analysis can be carried out. On the rastering of this beam synchronously with a video display using established scanning electron microscopy techniques, physical images and chemical distribution maps of the surface can be produced. Thus very small features, such as electronic circuit elements or corrosion pits in metals, can be investigated. Facilities are available on both XPS and AES instruments for depth-profiling of materials, using a beam of argon ions to sputter away consecutive layers of material to reveal sub-surface (and even semi-bulk) analyses.
Infante, Jeffrey R.; Taylor, Matthew H.; Patel, Manish R.; Wong, Deborah J.; Iannotti, Nicholas; Mehnert, Janice M.; Loos, Anja H.; Koch, Helga; Speit, Isabell; Gulley, James L.
2018-01-01
BACKGROUND Antibodies targeting the programmed death‐ligand 1 (PD‐L1)/programmed cell death protein 1 (PD‐1) checkpoint may cause adverse events (AEs) that are linked to the mechanism of action of this therapeutic class and unique from those observed with conventional chemotherapy. METHODS Patients with advanced solid tumors who were enrolled in the phase 1 JAVELIN Solid Tumor (1650 patients) and phase 2 JAVELIN Merkel 200 (88 patients) trials received avelumab, a human anti–PD‐L1 IgG1 antibody at a dose of 10 mg/kg every 2 weeks. Treatment‐related AEs (TRAEs) were graded using the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.0). In post hoc analyses, immune‐related AEs (irAEs) were identified via an expanded AE list and medical review, and infusion‐related reactions (IRRs) occurring ≤2 days after infusion and symptoms occurring ≤1 day after infusion and resolving ≤2 days after onset were identified based on prespecified Medical Dictionary for Regulatory Activities (MedDRA) terms. RESULTS Of the 1738 patients analyzed, grade ≥3 TRAEs occurred in 177 (10.2%); the most common were fatigue (17 patients; 1.0%) and IRR (10 patients; 0.6%). TRAEs led to discontinuation in 107 patients (6.2%) and death in 4 patients (0.2%). Grade ≥3 irAEs occurred in 39 patients (2.2%) and led to discontinuation in 34 patients (2.0%). IRRs or related symptoms occurred in 439 patients (25.3%; grade 3 in 0.5% [9 patients] and grade 4 in 0.2% [3 patients]). An IRR occurred at the time of first infusion in 79.5% of 439 patients who had an IRR, within the first 4 doses in 98.6% of 439 patients who had an IRR, and led to discontinuation in 35 patients (2.0%). CONCLUSIONS Avelumab generally was found to be well tolerated and to have a manageable safety profile. A minority of patients experienced grade ≥3 TRAEs or irAEs, and discontinuation was uncommon. IRRs occurred mainly at the time of first infusion, and repeated events were infrequent. Cancer 2018;124:2010‐7. © 2018 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the http://creativecommons.org/licenses/by-nc/4.0/ License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. PMID:29469949
Kelly, Karen; Infante, Jeffrey R; Taylor, Matthew H; Patel, Manish R; Wong, Deborah J; Iannotti, Nicholas; Mehnert, Janice M; Loos, Anja H; Koch, Helga; Speit, Isabell; Gulley, James L
2018-05-01
Antibodies targeting the programmed death-ligand 1 (PD-L1)/programmed cell death protein 1 (PD-1) checkpoint may cause adverse events (AEs) that are linked to the mechanism of action of this therapeutic class and unique from those observed with conventional chemotherapy. Patients with advanced solid tumors who were enrolled in the phase 1 JAVELIN Solid Tumor (1650 patients) and phase 2 JAVELIN Merkel 200 (88 patients) trials received avelumab, a human anti-PD-L1 IgG1 antibody at a dose of 10 mg/kg every 2 weeks. Treatment-related AEs (TRAEs) were graded using the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.0). In post hoc analyses, immune-related AEs (irAEs) were identified via an expanded AE list and medical review, and infusion-related reactions (IRRs) occurring ≤2 days after infusion and symptoms occurring ≤1 day after infusion and resolving ≤2 days after onset were identified based on prespecified Medical Dictionary for Regulatory Activities (MedDRA) terms. Of the 1738 patients analyzed, grade ≥3 TRAEs occurred in 177 (10.2%); the most common were fatigue (17 patients; 1.0%) and IRR (10 patients; 0.6%). TRAEs led to discontinuation in 107 patients (6.2%) and death in 4 patients (0.2%). Grade ≥3 irAEs occurred in 39 patients (2.2%) and led to discontinuation in 34 patients (2.0%). IRRs or related symptoms occurred in 439 patients (25.3%; grade 3 in 0.5% [9 patients] and grade 4 in 0.2% [3 patients]). An IRR occurred at the time of first infusion in 79.5% of 439 patients who had an IRR, within the first 4 doses in 98.6% of 439 patients who had an IRR, and led to discontinuation in 35 patients (2.0%). Avelumab generally was found to be well tolerated and to have a manageable safety profile. A minority of patients experienced grade ≥3 TRAEs or irAEs, and discontinuation was uncommon. IRRs occurred mainly at the time of first infusion, and repeated events were infrequent. Cancer 2018;124:2010-7. © 2018 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. © 2018 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.
76 FR 70953 - Pipeline Safety: Safety of Gas Transmission Pipelines
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-16
... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration 49 CFR Part 192 [Docket ID PHMSA-2011-0023] RIN 2137-AE72 Pipeline Safety: Safety of Gas Transmission Pipelines AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA); DOT. ACTION: Advance notice of...
NASA Technical Reports Server (NTRS)
Luu, D.
1999-01-01
This is the Performance Verification Report, AMSU-A1 Antenna Drive Subsystem, P/N 1331720-2, S/N 106, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A). The antenna drive subsystem of the METSAT AMSU-A1, S/N 106, P/N 1331720-2, completed acceptance testing per A-ES Test Procedure AE-26002/lD. The test included: Scan Motion and Jitter, Pulse Load Bus Peak Current and Rise Time, Resolver Reading and Position Error, Gain/ Phase Margin, and Operational Gain Margin. The drive motors and electronic circuitry were also tested at the component level. The drive motor test includes: Starting Torque Test, Motor Commutation Test, Resolver Operation/ No-Load Speed Test, and Random Vibration. The electronic circuitry was tested at the Circuit Card Assembly (CCA) level of production; each test exercised all circuit functions. The transistor assembly was tested during the W3 cable assembly (1356941-1) test.
Using neutral beams as a light ion beam probe (invited)
Chen, Xi; Heidbrink, William W.; Van Zeeland, Michael A.; ...
2014-08-05
By arranging the particle first banana orbits to pass near a distant detector, the light ion beam probe (LIBP) utilizes orbital deflection to probe internal fields and field fluctuations. The LIBP technique takes advantage of 1) the in situ, known source of fast ions created by beam-injected neutral particles that naturally ionize near the plasma edge, and 2) various commonly available diagnostics as its detector. These born trapped particles can traverse the plasma core on their inner banana leg before returning to the plasma edge. Orbital displacements (the forces on fast ions) caused by internal instabilities or edge perturbing fieldsmore » appear as modulated signal at an edge detector. Adjustments in the q-profile and plasma shape that determine the first orbit, as well as the relative position of the source and detector, enable studies under a wide variety of plasma conditions. This diagnostic technique can be used to probe the impact on fast ions of various instabilities, e.g. Alfvén eigenmodes (AEs) and neoclassical tearing modes, and of externally-imposed 3D fields, e.g. magnetic perturbations. To date, displacements by AEs and by externally applied resonant magnetic perturbation fields have been measured using a fast ion loss detector. Comparisons with simulations are shown. Additionally, nonlinear interactions between fast ions and independent AE waves are revealed by this technique.« less
Using neutral beams as a light ion beam probe (invited)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Xi, E-mail: chenxi@fusion.gat.com; Heidbrink, W. W.; Van Zeeland, M. A.
By arranging the particle first banana orbits to pass near a distant detector, the light ion beam probe (LIBP) utilizes orbital deflection to probe internal fields and field fluctuations. The LIBP technique takes advantage of (1) the in situ, known source of fast ions created by beam-injected neutral particles that naturally ionize near the plasma edge and (2) various commonly available diagnostics as its detector. These born trapped particles can traverse the plasma core on their inner banana leg before returning to the plasma edge. Orbital displacements (the forces on fast ions) caused by internal instabilities or edge perturbing fieldsmore » appear as modulated signal at an edge detector. Adjustments in the q-profile and plasma shape that determine the first orbit, as well as the relative position of the source and detector, enable studies under a wide variety of plasma conditions. This diagnostic technique can be used to probe the impact on fast ions of various instabilities, e.g., Alfvén eigenmodes (AEs) and neoclassical tearing modes, and of externally imposed 3D fields, e.g., magnetic perturbations. To date, displacements by AEs and by externally applied resonant magnetic perturbation fields have been measured using a fast ion loss detector. Comparisons with simulations are shown. In addition, nonlinear interactions between fast ions and independent AE waves are revealed by this technique.« less
Using neutral beams as a light ion beam probe (invited)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Xi; Heidbrink, William W.; Van Zeeland, Michael A.
By arranging the particle first banana orbits to pass near a distant detector, the light ion beam probe (LIBP) utilizes orbital deflection to probe internal fields and field fluctuations. The LIBP technique takes advantage of 1) the in situ, known source of fast ions created by beam-injected neutral particles that naturally ionize near the plasma edge, and 2) various commonly available diagnostics as its detector. These born trapped particles can traverse the plasma core on their inner banana leg before returning to the plasma edge. Orbital displacements (the forces on fast ions) caused by internal instabilities or edge perturbing fieldsmore » appear as modulated signal at an edge detector. Adjustments in the q-profile and plasma shape that determine the first orbit, as well as the relative position of the source and detector, enable studies under a wide variety of plasma conditions. This diagnostic technique can be used to probe the impact on fast ions of various instabilities, e.g. Alfvén eigenmodes (AEs) and neoclassical tearing modes, and of externally-imposed 3D fields, e.g. magnetic perturbations. To date, displacements by AEs and by externally applied resonant magnetic perturbation fields have been measured using a fast ion loss detector. Comparisons with simulations are shown. Additionally, nonlinear interactions between fast ions and independent AE waves are revealed by this technique.« less
Kim, Min Jung; Lee, Jihye; Kim, Seon Hee; Kim, Haidong; Lee, Kang-Bong; Lee, Yeonhee
2015-10-01
Chalcopyrite Cu(In, Ga)Se2 (CIGS) thin films are well known as the next-generation solar cell materials notable for their high absorption coefficient for solar radiation, suitable band gap, and ability for deposition on flexible substrate materials, allowing the production of highly flexible and lightweight solar panels. To improve solar cell performances, a quantitative and depth-resolved elemental analysis of photovoltaic thin films is much needed. In this study, Cu(In, Ga)Se2 thin films were prepared on molybdenum back contacts deposited on soda-lime glass substrates via three-stage evaporation. Surface analyses via AES and SIMS were used to characterize the CIGS thin films and compare their depth profiles. We determined the average concentration of the matrix elements, Cu, In, Ga, and Se, using ICP-AES, XRF, and EPMA. We also obtained depth profiling results using TOF-SIMS, magnetic sector SIMS and AES, and APT, a sub-nanometer resolution characterization technique that enables three-dimensional elemental mapping. The SIMS technique, with its high detection limit and ability to obtain the profiles of elements in parallel, is a powerful tool for monitoring trace elements in CIGS thin films. To identify impurities in a CIGS layer, the distribution of trace elements was also observed according to depth by SIMS and APT.
Stefanovic, Stefan; Wallwiener, Markus; Karic, Uros; Domschke, Christoph; Katic, Luka; Taran, Florin-Andrei; Pesic, Aleksandra; Hartkopf, Andreas; Hadji, Peyman; Teufel, Martin; Schuetz, Florian; Sohn, Christof; Fasching, Peter; Schneeweiss, Andreas; Brucker, Sara
2017-02-01
The capture of adequate treatment outcomes and quality of life (QOL) of advanced breast cancer patients in clinical routine represents a great challenge. Patient-reported outcomes (PROs) are data elements directly reported by patients about experiences with care, including symptoms, functional status, or quality of life. There is growing interest in the medical community for the evaluation and implementation of PROs of adverse events (PRO-AEs). Recent interest in PROs in health care has evolved in the context of patient centeredness. Our primary objective was to identify trials that had implemented PRO-AEs in the breast cancer treatment setting, thereby demonstrating its feasibility. We aimed to identify published studies that used patient reports to assess AEs during and after breast cancer treatment, to identify clinician underreported and modifiable AEs that are important to patients, and to analyze the feasibility and usefulness of PRO instrument implementation in everyday oncological practice with special attention given to electronic-based PRO instruments. We conducted a systematic search of PubMed for studies that used PRO instruments to assess AEs of breast cancer treatment in the metastatic and adjuvant settings. Two authors independently reviewed the search results and decided which studies fully met the predefined inclusion criteria. The search yielded 606 publications. The two reviewers found that 9 studies met the inclusion criteria. Three AEs were identified as important to patients but inadequately reported by health care providers, namely hot flushes, vaginal dryness, and weight gain. PROs and PRO-AEs are the consequence of contemporary concepts of patient-centered medicine and the growing feasibility, utility, and implications of collecting data using modern technology. Furthermore, the willingness of patients to utilize innovative applications for their own health has been increasing in parallel to the enhanced impact of the World Wide Web. Especially, the coverage of the metastatic situation promises numerous findings on the structure and quality of health care, enabling implementation of individually tailored interventions. Remote electronic self-reporting (i.e., home reporting) is feasible and is associated with high compliance levels.
Acoustic emission monitoring of CFRP cables for cable-stayed bridges
NASA Astrophysics Data System (ADS)
Rizzo, Piervincenzo; Lanza di Scalea, Francesco
2001-08-01
The advantages of fiber-reinforced polymer (FRP) composite include excellent corrosion resistance, high specific strength and stiffness, as well as outstanding fatigue behavior. The University of California San Diego's I- 5/Gilman Advanced Technology Bridge Project will help demonstrating the use of such materials in civil infrastructures. This paper presents an acoustic emission (AE) study performed during laboratory proof tests of carbon fiber-reinforced polymer stay-cables of possible use in the I-5/Gilman bridge. Three types of cables, both braided and single strand, were tested to failure at lengths ranging from 5500 mm to 5870 mm. AE allowed to monitor damage initiation and progression in the test pieces more accurately than the conventional load versus displacement curve. All of the cables exhibited acoustic activities revealing some degree of damage well before reaching final collapse, which is expected in FRP's. It was also shown that such cables are excellent acoustic waveguides exhibiting very low acoustic attenuation, which makes them an ideal application for an AE-based health monitoring approach.
Double take--fracture fishing in accident and emergency practice.
Hyland-McGuire, P; Guly, H R; Hughes, P M
1997-03-01
To investigate conditions where, after initially negative plain x rays following trauma, there subsequently proves to be fracture, and to explore ways in which the management might be improved. A 16 month prospective study. Patient details were collected from accident and emergency (A&E) review clinics and returns, A&E ward admissions, correspondence from other services, and discussions at a weekly clinicoradiological conference. The inclusion criteria comprised A&E trauma patients with normal initial plain x rays and proven fractures on subsequent imaging for the same patient event. A large A&E department seeing 65,000 new attendances per annum with full back up services. 55 cases were identified: 41 fractures were identified on subsequent plain x ray, six on bone scan, six on CAT scan, and two on MRI scan. The commonest regions involved were the wrist, pelvis/hip, ankle/foot, and leg. Follow up had not been arranged at the initial attendance in 17 instances and between two and 135 days were required for definitive fracture recognition. All but nine patients required alteration in treatment because of fracture detection. Clinical suspicion of fracture at initial A&E attendance should prompt organised follow up even in the face of normal plain x rays. Consideration should be given to alternative imaging techniques which may have a higher resolution than plain x rays. Close corroboration between A&E and radiology departments has benefits in patient care in this group of patients and may lead to a reduction in functional disability and litigation.
Sub-microanalysis of solid samples with near-field enhanced atomic emission spectroscopy
NASA Astrophysics Data System (ADS)
Wang, Xiaohua; Liang, Zhisen; Meng, Yifan; Wang, Tongtong; Hang, Wei; Huang, Benli
2018-03-01
A novel approach, which we have chosen to name it as near-field enhanced atomic emission spectroscopy (NFE-AES), was proposed by introducing a scanning tunnelling microscope (STM) system into a laser-induced breakdown spectrometry (LIBS). The near-field enhancement of a laser-illuminated tip was utilized to improve the lateral resolution tremendously. Using the hybrid arrangement, pure metal tablets were analyzed to verify the performance of NFE-AES both in atmosphere and in vacuum. Due to localized surface plasmon resonance (LSPR), the incident electromagnetic field is enhanced and confined at the apex of tip, resulting in sub-micron scale ablation and elemental emission signal. We discovered that the signal-to-noise ratio (SNR) and the spectral resolution obtained in vacuum condition are better than those acquired in atmospheric condition. The quantitative capability of NFE-AES was demonstrated by analyzing Al and Pb in Cu matrix, respectively. Submicron-sized ablation craters were achieved by performing NFE-AES on a Si wafer with an Al film, and the spectroscopic information from a crater of 650 nm diameter was successfully obtained. Due to its advantage of high lateral resolution, NFE-AES imaging of micro-patterned Al lines on an integrated circuit of a SIM card was demonstrated with a sub-micron lateral resolution. These results reveal the potential of the NFE-AES technique in sub-microanalysis of solids, opening an opportunity to map chemical composition at sub-micron scale.
Sant, R; Bakke, D
1999-01-01
The topic of empowerment is receiving a lot of attention, but how many employees are truly empowered? At the global electricity giant AES Corporation, the answer is all 40,000 of them. In this interview, chairman Roger Sant and CEO Dennis Bakke reflect on their trials and triumphs in creating an exceptional company and explain how their employee-run company works. When they founded AES in 1981, Sant and Bakke set out to create a company where people could have engaging experiences on a daily basis--a company that embodied the principles of fairness, integrity, social responsibility, and fun. Putting those principles into action has created something unique--an ecosystem of real empowerment. What does that system look like? Rather than having a traditional hierarchical chain of command, AES is organized around small teams that are responsible for operations and maintenance. Moreover, AES has eliminated functional departments; there's no corporate marketing division or human resources department. For the system to work, every person must become a well-rounded generalist--a mini-CEO. That, in turn, redefines the jobs of the people at headquarters. Instead of setting strategy and making the "the big decisions," Sant and Bakke act as advisers, guardians of the principles, accountability officers, and chief encouragers. Can other companies successfully adopt the mechanics of such a system? Not unless they first adopt the shared principles that have guided AES since its inception. "Empowerment without values isn't empowerment," says Sant. "It's just technique," adds Bakke.
A new method to estimate location and slip of simulated rock failure events
NASA Astrophysics Data System (ADS)
Heinze, Thomas; Galvan, Boris; Miller, Stephen Andrew
2015-05-01
At the laboratory scale, identifying and locating acoustic emissions (AEs) is a common method for short term prediction of failure in geomaterials. Above average AE typically precedes the failure process and is easily measured. At larger scales, increase in micro-seismic activity sometimes precedes large earthquakes (e.g. Tohoku, L'Aquilla, oceanic transforms), and can be used to assess seismic risk. The goal of this work is to develop a methodology and numerical algorithms for extracting a measurable quantity analogous to AE arising from the solution of equations governing rock deformation. Since there is no physical property to quantify AE derivable from the governing equations, an appropriate rock-mechanical analog needs to be found. In this work, we identify a general behavior of the AE generation process preceding rock failure. This behavior includes arbitrary localization of low magnitude events during pre-failure stage, followed by increase in number and amplitude, and finally localization around the incipient failure plane during macroscopic failure. We propose deviatoric strain rate as the numerical analog that mimics this behavior, and develop two different algorithms designed to detect rapid increases in deviatoric strain using moving averages. The numerical model solves a fully poro-elasto-plastic continuum model and is coupled to a two-phase flow model. We test our model by comparing simulation results with experimental data of drained compression and of fluid injection experiments. We find for both cases that occurrence and amplitude of our AE analog mimic the observed general behavior of the AE generation process. Our technique can be extended to modeling at the field scale, possibly providing a mechanistic basis for seismic hazard assessment from seismicity that occasionally precedes large earthquakes.
Damage characterization on human femur bone by means of ultrasonics and acoustic emission
NASA Astrophysics Data System (ADS)
Strantza, M.; Polyzos, D.; Louis, O.; Boulpaep, F.; Van Hemelrijck, D.; Aggelis, D. G.
2015-07-01
Human bone tissue is characterized as a material with high brittleness. Due to this nature, visible signs of cracking are not easy to be detected before final failure. The main objective of this work is to investigate if the acoustic emission (AE) technique can offer valuable insight to the fracture process of human femur specimens as in other engineering materials characterization. This study describes the AE activity during fracture of whole femur bones under flexural load. Before fracture, broadband AE sensors were used in order to measure parameters like wave velocity dispersion and attenuation. Waveform parameters like the duration, rise time and average frequency, were also examined relatively to the propagation distance as a preparation for the AE monitoring during fracture. After the ultrasonic study, the samples were partly cast in concrete and fixed as cantilevers. A point load was applied on the femur head, which due to the test geometry resulted in a combination of two different patterns of fracture, bending and torsion. Two AE broadband sensors were placed in different points of the sample, one near the fixing end and the other near the femur head. Preliminary analysis shows that parameters like the number of acquired AE signals and their amplitude are well correlated with the load history. Furthermore, the parameters of rise time and frequency can differentiate the two fracture patterns. Additionally, AE allows the detection of the load at the onset of fracture from the micro-cracking events that occur at the early loading stages, allowing monitoring of the whole fracture process. Parameters that have been used extensively for monitoring and characterization of fracture modes of engineering materials seem to poses characterization power in the case of bone tissue monitoring as well.
CORROSION PROCESS IN REINFORCED CONCRETE IDENTIFIED BY ACOUSTIC EMISSION
NASA Astrophysics Data System (ADS)
Kawasaki, Yuma; Kitaura, Misuzu; Tomoda, Yuichi; Ohtsu, Masayasu
Deterioration of Reinforced Concrete (RC) due to salt attack is known as one of serious problems. Thus, development of non-destructive evaluation (NDE) techniques is important to assess the corrosion process. Reinforcement in concrete normally does not corrode because of a passive film on the surface of reinforcement. When chloride concentration at reinfo rcement exceeds the threshold level, the passive film is destroyed. Thus maintenance is desirable at an early stage. In this study, to identify the onset of corrosion and the nucleation of corrosion-induced cracking in concrete due to expansion of corrosion products, continuous acoustic emission (AE) monitoring is applied. Accelerated corrosion and cyclic wet and dry tests are performed in a laboratory. The SiGMA (Simplified Green's functions for Moment tensor Analysis) proce dure is applied to AE waveforms to clarify source kinematics of micro-cracks locations, types and orientations. Results show that the onset of corrosion and the nu cleation of corrosion-induced cracking in concrete are successfully identified. Additionally, cross-sections inside the reinforcement are observed by a scanning electron microscope (SEM). From these results, a great promise for AE techniques to monitor salt damage at an early stage in RC structures is demonstrated.
NASA Astrophysics Data System (ADS)
Xie, Jing; Xu, Changhang; Chen, Guoming; Huang, Weiping
2018-06-01
Inductive thermography is one kind of infrared thermography (IRT) technique, which is effective in detection of front surface cracks in metal plates. However, rear surface cracks are usually missed due to their weak indications during inductive thermography. Here we propose a novel approach (AET: AE Thermography) to improve the visibility of rear surface cracks during inductive thermography by employing the Autoencoder (AE) algorithm, which is an important block to construct deep learning architectures. We construct an integrated framework for processing the raw inspection data of inductive thermography using the AE algorithm. Through this framework, underlying features of rear surface cracks are efficiently extracted and new clearer images are constructed. Experiments of inductive thermography were conducted on steel specimens to verify the efficacy of the proposed approach. We visually compare the raw thermograms, the empirical orthogonal functions (EOFs) of the prominent component thermography (PCT) technique and the results of AET. We further quantitatively evaluated AET by calculating crack contrast and signal-to-noise ratio (SNR). The results demonstrate that the proposed AET approach can remarkably improve the visibility of rear surface cracks and then improve the capability of inductive thermography in detecting rear surface cracks in metal plates.
Zhang, Dongjing; Zheng, Xiaoying; Xi, Zhiyong; Bourtzis, Kostas; Gilles, Jeremie R. L.
2015-01-01
The mosquito species Aedes albopictus is a major vector of the human diseases dengue and chikungunya. Due to the lack of efficient and sustainable methods to control this mosquito species, there is an increasing interest in developing and applying the sterile insect technique (SIT) and the incompatible insect technique (IIT), separately or in combination, as population suppression approaches. Ae. albopictus is naturally double-infected with two Wolbachia strains, wAlbA and wAlbB. A new triple Wolbachia-infected strain (i.e., a strain infected with wAlbA, wAlbB, and wPip), known as HC and expressing strong cytoplasmic incompatibility (CI) in appropriate matings, was recently developed. In the present study, we compared several fitness traits of three Ae. albopictus strains (triple-infected, double-infected and uninfected), all of which were of the same genetic background (“Guangzhou City, China”) and were reared under the same conditions. Investigation of egg-hatching rate, survival of pupae and adults, sex ratio, duration of larval stages (development time from L1 to pupation), time to emergence (development time from L1 to adult emergence), wing length, female fecundity and adult longevity indicated that the presence of Wolbachia had only a minimal effect on host fitness. Based on this evidence, the HC strain is currently under consideration for mass rearing and application in a combined SIT-IIT strategy to control natural populations of Ae. albopictus in mainland China. PMID:25849812
ASCA X-ray observations of pre-main-sequence stars
NASA Technical Reports Server (NTRS)
Skinner, S. L.; Walter, F. M.; Yamauchi, S.
1996-01-01
The results of recent Advanced Satellite for Cosmology and Astrophysics (ASCA) X-ray observations of two pre-main sequence stars are presented: the weak emission line T Tauri star HD 142361, and the Herbig Ae star HD 104237. The solid state imaging spectrometer spectra for HD 142361 shows a clear emission line from H-like Mg 7, and spectral fits reveal a multiple temperature plasma with a hot component of at least 16 MK. The spectra of HD 104237 show a complex temperature structure with the hottest plasma at temperatures of greater than 30 MK. It is concluded that mechanisms that predict only soft X-ray emission can be dismissed for Herbig Ae stars.
Systemic therapy for intermediate and advanced hepatocellular carcinoma: Sorafenib and beyond.
Raoul, Jean-Luc; Kudo, Masatoshi; Finn, Richard S; Edeline, Julien; Reig, Maria; Galle, Peter R
2018-05-17
The hepatocellular carcinoma (HCC) treatment landscape changed a decade ago, with sorafenib demonstrating survival benefit in the first-line setting and becoming the first systemic therapy to be approved for HCC. More recently, regorafenib and nivolumab have received approval in the second-line setting after sorafenib, with further positive phase 3 studies emerging in the first line (lenvatinib non-inferior to sorafenib) and second line versus placebo (cabozantinib and ramucirumab). A key recommendation in the management of patients receiving sorafenib is to promote close communication between the patient and the physician so that adverse events (AEs) are detected early and severe AEs can be prevented. Sorafenib-related AEs have been identified as clinical biomarkers for sorafenib efficacy. Healthcare professionals have become more efficient in managing AEs, identifying patients who are likely to benefit from treatment, and assessing response to treatment, resulting in a trend towards increased overall survival in the sorafenib arms of clinical studies. The rapidly changing treatment landscape due to the emergence of new treatment options (sorafenib and lenvatinib equally effective in first line; regorafenib, cabozantinib, and ramucirumab showing OS benefit in second line with nivolumab approved by the FDA based on response rate) underscores the importance of re-assessing the role of the first approved systemic agent in HCC, sorafenib. Copyright © 2018. Published by Elsevier Ltd.
NASA Astrophysics Data System (ADS)
Matsubara, Atsuko; Kojima, Hisao; Itoga, Toshihiko; Kanehori, Keiichi
1995-08-01
High resolution depth profiling of arsenic (As) implanted into silicon wafers by a chemical technique is described. Silicon wafers are precisely etched through repeated oxidation by hydrogen peroxide solution and dissolution of the oxide by hydrofluoric acid solution. The etched silicon thickness is determined by inductively-coupled plasma atomic emission spectrometry (ICP-AES). Arsenic concentration is determined by hydride generation ICP-AES (HG-ICP-AES) with prereduction using potassium iodide. The detection limit of As in a 4-inch silicon wafer is 2.4×1018 atoms/cm3. The etched silicon thickness is controlled to less than 4±2 atomic layers. Depth profiling of an ultra-shallow As diffusion layer with the proposed method shows good agreement with profiling using the four-probe method or secondary ion mass spectrometry.
Monitoring the fracture behavior of metal matrix composites by combined NDE methodologies
NASA Astrophysics Data System (ADS)
Kordatos, E. Z.; Exarchos, D. A.; Mpalaskas, A. C.; Matikas, T. E.
2015-03-01
Current work deals with the non-destructive evaluation (NDE) of the fatigue behavior of metal matrix composites (MMCs) materials using Infrared Thermography (IRT) and Acoustic Emission (AE). AE monitoring was employed to record a wide spectrum of cracking events enabling the characterization of the severity of fracture in relation to the applied load. IR thermography as a non-destructive, real-time and non-contact technique, allows the detection of heat waves generated by the thermo-mechanical coupling during mechanical loading of the sample. In this study an IR methodology, based on the monitoring of the intrinsically dissipated energy, was applied for the determination of the fatigue limit of A359/SiCp composites. The thermographic monitoring is in agreement with the AE results enabling the reliable monitoring of the MMCs' fatigue behavior.
Nondestructive damage evaluation in ceramic matrix composites for aerospace applications.
Dassios, Konstantinos G; Kordatos, Evangelos Z; Aggelis, Dimitrios G; Matikas, Theodore E
2013-01-01
Infrared thermography (IRT) and acoustic emission (AE) are the two major nondestructive methodologies for evaluating damage in ceramic matrix composites (CMCs) for aerospace applications. The two techniques are applied herein to assess and monitor damage formation and evolution in a SiC-fiber reinforced CMC loaded under cyclic and fatigue loading. The paper explains how IRT and AE can be used for the assessment of the material's performance under fatigue. IRT and AE parameters are specifically used for the characterization of the complex damage mechanisms that occur during CMC fracture, and they enable the identification of the micromechanical processes that control material failure, mainly crack formation and propagation. Additionally, these nondestructive parameters help in early prediction of the residual life of the material and in establishing the fatigue limit of materials rapidly and accurately.
Evaluation of Information Leakage from Cryptographic Hardware via Common-Mode Current
NASA Astrophysics Data System (ADS)
Hayashi, Yu-Ichi; Homma, Naofumi; Mizuki, Takaaki; Sugawara, Takeshi; Kayano, Yoshiki; Aoki, Takafumi; Minegishi, Shigeki; Satoh, Akashi; Sone, Hideaki; Inoue, Hiroshi
This paper presents a possibility of Electromagnetic (EM) analysis against cryptographic modules outside their security boundaries. The mechanism behind the information leakage is explained from the view point of Electromagnetic Compatibility: electric fluctuation released from cryptographic modules can conduct to peripheral circuits based on ground bounce, resulting in radiation. We demonstrate the consequence of the mechanism through experiments where the ISO/IEC standard block cipher AES (Advanced Encryption Standard) is implemented on an FPGA board and EM radiations from power and communication cables are measured. Correlation Electromagnetic Analysis (CEMA) is conducted in order to evaluate the information leakage. The experimental results show that secret keys are revealed even though there are various disturbing factors such as voltage regulators and AC/DC converters between the target module and the measurement points. We also discuss information-suppression techniques as electrical-level countermeasures against such CEMAs.
Honeywell Cascade Distiller System Performance Testing Interim Results
NASA Technical Reports Server (NTRS)
Callahan, Michael R.; Sargusingh, Miriam
2014-01-01
The ability to recover and purify water through physiochemical processes is crucial for realizing long-term human space missions, including both planetary habitation and space travel. Because of their robust nature, distillation systems have been actively pursued as one of the technologies for water recovery. The Cascade Distillation System (CDS) is a vacuum rotary distillation system with potential for greater reliability and lower energy costs than existing distillation systems. The CDS was previously under development through Honeywell and NASA. In 2009, an assessment was performed to collect data to support down-selection and development of a primary distillation technology for application in a lunar outpost water recovery system. Based on the results of this testing, an expert panel concluded that the CDS showed adequate development maturity, TRL-4, together with the best product water quality and competitive weight and power estimates to warrant further development. The Advanced Exploration Systems (AES) Water Recovery Project (WRP) worked to address weaknesses identified by The Panel; namely bearing design and heat pump power efficiency. Testing at the NASA-JSC Advanced Exploration System Water Laboratory (AES Water Lab) using a prototype Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell International, Torrance, Calif.) with test support equipment and control system developed by Johnson Space Center was performed to evaluate performance of the system with the upgrades. The CDS will also have been challenged with ISS analog waste streams and a subset of those being considered for Exploration architectures. This paper details interim results of the AES WRP CDS performance testing.
Study of Electron G-2 From 1947 To Present
NASA Astrophysics Data System (ADS)
Kinoshita, Toichiro
2014-03-01
In 1947 Kusch and Foley discovered in the study of Zeeman splitting of Ga atom that the electron g-factor was about 0.2% larger than the value 2 predicted by the Dirac equation. Soon afterwards Schwinger showed that it can be explained as the effect of radiative correction. His calculation, in the second order perturbation theory of the Lorentz invariant formulation of renormalized quantum electrodynamics, showed that the electron has an excess magnetic moment ae ≡ (g - 2) / 2 = α / (2 π) , where α is the fine structure constant, in agreement with the measurement within 3%. Thus began a long series of friendly competition between experimentalists and theorists to improve the precision of ae. Over the period of more than 60 years measurement precision of ae was improved by more than 104 by the spin precession technique, and further 103 by the Penning trap experiments. In step with the progress of measurement, the theory of ae, expressed as a power series in α, has been pushed to the fifth power of α. Including small contributions from hadronic effects and weak interaction effect and using the best non-QED value of α: α-1 = 137 . 035999049 (90) , one finds ae (theory) = 1159652181 . 72 (77) ×10-12 . The uncertainty is about 0 . 66 ppb , where 1 ppb =10-9 . The intrinsic uncertainty of theory itself is less than 0 . 1 ppb . The over all uncertainty comes mostly from the uncertainty of non-QED α mentioned above, which is about 0 . 66 ppb . This is in good agreement with the latest measurement: ae (experiment) = 1159652180 . 73 (28) ×10-12 . The uncertainty of measurement is 0 . 24 ppb . An alternate approach to test QED is to assume the validity of QED (and the Standard Model of particle physics) and obtain α by solving the equation ae (experiment) =ae (theory) . This yields α-1 (ae) = 137 . 0359991727 (342) , whose uncertainty is 0 . 25 ppb , better than α obtained by any other means. Although comparison of theory and experiment of ae began historically as a test of the validity of QED, it has now evolved into a precision test of fine structure constant at the level exceeding 1 ppb , which may be regarded as a test of internal consistency of quantum mechanics as a whole. Supported in part by the U. S. National Science Foundation under Grant No. NSF-PHY-0757868.
Caivano, Marianna; Bellandi, Giacomo; Mancini, Ignazio M; Masi, Salvatore; Brienza, Rosanna; Panariello, Simona; Gori, Riccardo; Caniani, Donatella
2017-03-01
The efficiency of aeration systems should be monitored to guarantee suitable biological processes. Among the available tools for evaluating the aeration efficiency, the off-gas method is one of the most useful. Increasing interest towards reducing greenhouse gas (GHG) emissions from biological processes has resulted in researchers using this method to quantify N 2 O and CO 2 concentrations in the off-gas. Experimental measurements of direct GHG emissions from aerobic digesters (AeDs) are not available in literature yet. In this study, the floating hood technique was used for the first time to monitor AeDs. The floating hood technique was used to evaluate oxygen transfer rates in an activated sludge (AS) tank of a medium-sized municipal wastewater treatment plant located in Italy. Very low values of oxygen transfer efficiency were found, confirming that small-to-medium-sized plants are often scarcely monitored and wrongly managed. Average CO 2 and N 2 O emissions from the AS tank were 0.14 kg CO2 /kg bCOD and 0.007 kg CO2,eq /kg bCOD , respectively. For an AeD, 3 × 10 -10 kg CO2 /kg bCOD direct CO 2 emissions were measured, while CO 2,eq emissions from N 2 O were 4 × 10 -9 kg CO2,eq /kg bCOD . The results for the AS tank and the AeD were used to estimate the net carbon and energy footprint of the entire plant.
Acoustic emission of retrofitted fiber-wrapped columns
NASA Astrophysics Data System (ADS)
El Echary, Hazem; Mirmiran, Amir
1998-03-01
In recent years, fiber-wrapping technique has become increasingly popular for retrofitting of existing bridge pier columns in seismic zones. By the way of confinement, the external jacket enhances strength, ductility and shear performance of the column. However, since state of the concrete core is not visible from outside of the jacket, it is of great necessity to develop proper non-destructive methods to evaluate structural integrity of the column. Extensive research on FRP-confined concrete at the University of Central Florida has shown that failure of such hybrid columns is often accompanied by considerable audible and sub-audible noise, making acoustic emission (AE) a viable NDE technique for retrofitted columns. Acoustic emission from fiber-wrapped concrete specimens were monitored. A total of 24 concrete specimens with two types of construction (bonded and unbonded) and four different number of layers (1, 3, 5 and 7) were tested under uniaxial compression. All specimens were made of S-glass fabric and polyester resin with a core diameter of 6' and a length of 12'. Some of the specimens were subjected to cycles of loading and unloading to examine the presence of the Kaiser and the Felicity effects. A 4-channel AEDSP-32/16 (Mistras-2001) machine from Physical Acoustics Corp. was used for the experiments. Results indicate that AE energy and the number of AE counts can both be good representatives for the response of confined concrete. Further, plots of AE energy versus load follows the same bilinear trend that has been observed in the stress-strain response of such specimens. Finally, Felicity effect was observed in all composite specimens.
Zhang, Weidong; Randell, Edward W.; Sun, Guang; Likhodii, Sergei; Liu, Ming; Furey, Andrew
2017-01-01
To test whether type 2 diabetic patients have an elevated level of advanced glycation end-products (AGEs) and responsible for altered phosphatidylcholine metabolism, which we recently found to be associated with osteoarthritis (OA) and diabetes mellitus (DM), synovial fluid (SF) and plasma samples were collected from OA patients with and without DM. Hyperglycemia-related AGEs including methylglyoxal (MG), free methylglyoxal-derived hydroimidazolone (MG-H1), and protein bound N-(Carboxymethyl)lysine (CML) and N-(Carboxyethyl)lysine (CEL) levels were measured in both SF and plasma samples using liquid chromatography coupled tandem mass spectrometry methodology. The correlation between these AGEs and phosphatidylcholine acyl-alkyl C34:3 (PC ae C34:3) and C36:3 (PC ae C36:3) were examined. Eighty four patients with knee OA, including 46 with DM and 38 without DM, were included in the study. There was no significant difference in plasma levels of MG, MG-H1, CML, and CEL between OA patients with and without DM. However, the levels of MG and MG-H1, but not CML and CEL in SF were significantly higher in OA patients with DM than in those without (all p ≤0.04). This association strengthened after adjustment for age, body mass index (BMI), sex and hexose level (p<0.02). Moreover, the levels of MG-H1 in SF was negatively and significantly correlated with PC ae C34:3 (ρ = -0.34; p = 0.02) and PC ae C36:3 (ρ = -0.39; P = 0.03) after the adjustment of age, BMI, sex and hexose level. Our data indicated that the production of non-protein bound AGEs was increased within the OA-affected joint of DM patients. This is associated with changes in phosphatidylcholine metabolism and might be responsible for the observed epidemiological association between OA and DM. PMID:28898260
Dadu, Ramona; Shah, Komal; Busaidy, Naifa L; Waguespack, Steven G; Habra, Mouhammad A; Ying, Anita K; Hu, Mimi I; Bassett, Roland; Jimenez, Camilo; Sherman, Steven I; Cabanillas, Maria E
2015-01-01
Vemurafenib, a selective BRAF inhibitor, appears to have promising clinical activity in patients with papillary thyroid cancer (PTC) harboring the BRAF(V600E) mutation. To determine the efficacy and safety of vemurafenib when used outside of a clinical trial. A retrospective review at MD Anderson Cancer Center. The best responses were evaluated using RECIST v1.1. A single radiologist reviewed all images. Adverse events (AEs) were evaluated using CTCAE v.4.0. We identified 17 patients with advanced PTC harboring the BRAF(V600E) mutation who were treated with vemurafenib outside of a clinical trial. Median age at diagnosis was 63 years, and 53% were male. At vemurafenib start, 3 (18%) patients had disease confined to the neck, and 14 (72%) had distant metastases. Tyrosine kinase inhibitors had been previously administered to 4 (24%) patients. Two (12%) patients discontinued vemurafenib because of AEs before restaging. Best response: partial response (PR) in 7/15 (47%) and stable disease (SD) in 8/15(53%) patients. The rate of durable response (PR plus SD ≥ 6 months) was 67%. Median time to treatment failure was 13 months. There was no association between change in thyroglobulin and tumor size. Drug discontinuation, drug interruptions, and dose reductions were needed in 5 (29%), 13 (76%), and 10 (59%) patients, respectively. Most common AEs were fatigue (71%), weight loss (71%), anorexia (65%), arthralgias (59%), hair loss (59%), rash (59%), hand-foot syndrome (53%), calluses (47%), diarrhea (47%), fever (41%), dry mouth (35%), nausea (35%), and verrucous keratosis (35%). Grade ≥ 3 AEs were present in 8 (47%) patients. Vemurafenib is a potentially effective and well-tolerated treatment strategy in patients with advanced PTC harboring the BRAF(V600E) mutation. Our results are similar to those reported in a phase II clinical trial and support the potential role of vemurafenib in this patient population.
Nishijima, Tomohiro F; Shachar, Shlomit S; Nyrop, Kirsten A; Muss, Hyman B
2017-04-01
Compared with chemotherapy, significant improvement in survival outcomes with the programmed death receptor-1 (PD-1) inhibitors nivolumab and pembrolizumab and the programmed death-ligand 1 (PD-L1) inhibitor atezolizumab has been shown in several types of advanced solid tumors. We conducted a systematic review and meta-analysis to compare safety and tolerability between PD-1/PD-L1 inhibitors and chemotherapy. PubMed and American Society of Clinical Oncology (ASCO) databases were searched 1966 to September 2016. Eligible studies included randomized controlled trials (RCTs) comparing single-agent U.S. Food and Drug Administration-approved PD-1/PD-L1 inhibitors (nivolumab, pembrolizumab, or atezolizumab) with chemotherapy in cancer patients reporting any all-grade (1-4) or high-grade (3-4) adverse events (AEs), all- or high-grade treatment-related symptoms, hematologic toxicities and immune-related AEs, treatment discontinuation due to toxicities, or treatment-related deaths. The summary incidence, relative risk, and 95% confidence intervals were calculated. A total of 3,450 patients from 7 RCTs were included in the meta-analysis: 4 nivolumab, 2 pembrolizumab, and 1 atezolizumab trials. The underlying malignancies included were non-small cell lung cancer (4 trials) and melanoma (3 trials). Compared with chemotherapy, the PD-1/PD-L1 inhibitors had a significantly lower risk of all- and high-grade fatigue, sensory neuropathy, diarrhea and hematologic toxicities, all-grade anorexia, nausea, and constipation, any all- and high-grade AEs, and treatment discontinuation. There was an increased risk of all-grade rash, pruritus, colitis, aminotransferase elevations, hypothyroidism, and hyperthyroidism, and all- and high-grade pneumonitis with PD1/PD-L1 inhibitors. PD-1/PD-L1 inhibitors are overall better tolerated than chemotherapy. Our results provide further evidence supporting the favorable risk/benefit ratio for PD-1/PD-L1 inhibitors. The Oncologist 2017;22:470-479 IMPLICATIONS FOR PRACTICE: We conducted a systematic review and meta-analysis to compare summary toxicity endpoints and clinically relevant adverse events between programmed death receptor-1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors and chemotherapy. PD1/PD-L1 inhibitors were associated with a lower risk of treatment-related symptoms (fatigue, anorexia, nausea, diarrhea, constipation, and sensory neuropathy) but a higher risk of immune-related adverse events (AEs). Summary toxicity endpoints favor PD1/PD-L1 inhibitors (any all- and high-grade AEs and treatment discontinuation). PD1/PD-L1 inhibitors are overall better tolerated than chemotherapy. In addition to efficacy data from trials, our findings provide useful information for clinicians for well-balanced discussions with their patients on the risks and benefits of treatment options for advanced cancer. © AlphaMed Press 2017.
Shachar, Shlomit S.; Nyrop, Kirsten A.; Muss, Hyman B.
2017-01-01
Abstract Background. Compared with chemotherapy, significant improvement in survival outcomes with the programmed death receptor‐1 (PD‐1) inhibitors nivolumab and pembrolizumab and the programmed death‐ligand 1 (PD‐L1) inhibitor atezolizumab has been shown in several types of advanced solid tumors. We conducted a systematic review and meta‐analysis to compare safety and tolerability between PD‐1/PD‐L1 inhibitors and chemotherapy. Methods. PubMed and American Society of Clinical Oncology (ASCO) databases were searched 1966 to September 2016. Eligible studies included randomized controlled trials (RCTs) comparing single‐agent U.S. Food and Drug Administration–approved PD‐1/PD‐L1 inhibitors (nivolumab, pembrolizumab, or atezolizumab) with chemotherapy in cancer patients reporting any all‐grade (1–4) or high‐grade (3–4) adverse events (AEs), all‐ or high‐grade treatment‐related symptoms, hematologic toxicities and immune‐related AEs, treatment discontinuation due to toxicities, or treatment‐related deaths. The summary incidence, relative risk, and 95% confidence intervals were calculated. Results. A total of 3,450 patients from 7 RCTs were included in the meta‐analysis: 4 nivolumab, 2 pembrolizumab, and 1 atezolizumab trials. The underlying malignancies included were non‐small cell lung cancer (4 trials) and melanoma (3 trials). Compared with chemotherapy, the PD‐1/PD‐L1 inhibitors had a significantly lower risk of all‐ and high‐grade fatigue, sensory neuropathy, diarrhea and hematologic toxicities, all‐grade anorexia, nausea, and constipation, any all‐ and high‐grade AEs, and treatment discontinuation. There was an increased risk of all‐grade rash, pruritus, colitis, aminotransferase elevations, hypothyroidism, and hyperthyroidism, and all‐ and high‐grade pneumonitis with PD1/PD‐L1 inhibitors. Conclusion. PD‐1/PD‐L1 inhibitors are overall better tolerated than chemotherapy. Our results provide further evidence supporting the favorable risk/benefit ratio for PD‐1/PD‐L1 inhibitors. Implications for Practice. We conducted a systematic review and meta‐analysis to compare summary toxicity endpoints and clinically relevant adverse events between programmed death receptor‐1 (PD‐1)/programmed death‐ligand 1 (PD‐L1) inhibitors and chemotherapy. PD1/PD‐L1 inhibitors were associated with a lower risk of treatment‐related symptoms (fatigue, anorexia, nausea, diarrhea, constipation, and sensory neuropathy) but a higher risk of immune‐related adverse events (AEs). Summary toxicity endpoints favor PD1/PD‐L1 inhibitors (any all‐ and high‐grade AEs and treatment discontinuation). PD1/PD‐L1 inhibitors are overall better tolerated than chemotherapy. In addition to efficacy data from trials, our findings provide useful information for clinicians for well‐balanced discussions with their patients on the risks and benefits of treatment options for advanced cancer. PMID:28275115
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coleman, Charles J.; Edwards, Thomas B.
2005-04-30
The wet chemistry digestion method development for providing process control elemental analyses of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Melter Feed Preparation Vessel (MFPV) samples is divided into two phases: Phase I consists of: (1) optimizing digestion methods as a precursor to elemental analyses by ICP-AES techniques; (2) selecting methods with the desired analytical reliability and speed to support the nine-hour or less turnaround time requirement of the WTP; and (3) providing baseline comparison to the laser ablation (LA) sample introduction technique for ICP-AES elemental analyses that is being developed at the Savannah River National Laboratory (SRNL).more » Phase II consists of: (1) Time-and-Motion study of the selected methods from Phase I with actual Hanford waste or waste simulants in shielded cell facilities to ensure that the methods can be performed remotely and maintain the desired characteristics; and (2) digestion of glass samples prepared from actual Hanford Waste tank sludge for providing comparative results to the LA Phase II study. Based on the Phase I testing discussed in this report, a tandem digestion approach consisting of sodium peroxide fusion digestions carried out in nickel crucibles and warm mixed-acid digestions carried out in plastic bottles has been selected for Time-and-Motion study in Phase II. SRNL experience with performing this analytical approach in laboratory hoods indicates that well-trained cell operator teams will be able to perform the tandem digestions in five hours or less. The selected approach will produce two sets of solutions for analysis by ICP-AES techniques. Four hours would then be allocated for performing the ICP-AES analyses and reporting results to meet the nine-hour or less turnaround time requirement. The tandem digestion approach will need to be performed in two separate shielded analytical cells by two separate cell operator teams in order to achieve the nine-hour or less turnaround time. Because of the simplicity of the warm mixed-acid method, a well-trained cell operator team may in time be able to perform both sets of digestions. However, having separate shielded cells for each of the methods is prudent to avoid overcrowding problems that would impede a minimal turnaround time.« less
A laboratory nanoseismological study on deep-focus earthquake micromechanics
Wang, Yanbin; Zhu, Lupei; Shi, Feng; Schubnel, Alexandre; Hilairet, Nadege; Yu, Tony; Rivers, Mark; Gasc, Julien; Addad, Ahmed; Deldicque, Damien; Li, Ziyu; Brunet, Fabrice
2017-01-01
Global earthquake occurring rate displays an exponential decay down to ~300 km and then peaks around 550 to 600 km before terminating abruptly near 700 km. How fractures initiate, nucleate, and propagate at these depths remains one of the greatest puzzles in earth science, as increasing pressure inhibits fracture propagation. We report nanoseismological analysis on high-resolution acoustic emission (AE) records obtained during ruptures triggered by partial transformation from olivine to spinel in Mg2GeO4, an analog to the dominant mineral (Mg,Fe)2SiO4 olivine in the upper mantle, using state-of-the-art seismological techniques, in the laboratory. AEs’ focal mechanisms, as well as their distribution in both space and time during deformation, are carefully analyzed. Microstructure analysis shows that AEs are produced by the dynamic propagation of shear bands consisting of nanograined spinel. These nanoshear bands have a near constant thickness (~100 nm) but varying lengths and self-organize during deformation. This precursory seismic process leads to ultimate macroscopic failure of the samples. Several source parameters of AE events were extracted from the recorded waveforms, allowing close tracking of event initiation, clustering, and propagation throughout the deformation/transformation process. AEs follow the Gutenberg-Richter statistics with a well-defined b value of 1.5 over three orders of moment magnitudes, suggesting that laboratory failure processes are self-affine. The seismic relation between magnitude and rupture area correctly predicts AE magnitude at millimeter scales. A rupture propagation model based on strain localization theory is proposed. Future numerical analyses may help resolve scaling issues between laboratory AE events and deep-focus earthquakes. PMID:28776024
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gorelenkov, Nikolai N
The area of energetic particle (EP) physics of fusion research has been actively and extensively researched in recent decades. The progress achieved in advancing and understanding EP physics has been substantial since the last comprehensive review on this topic by W.W. Heidbrink and G.J. Sadler [1]. That review coincided with the start of deuterium-tritium (DT) experiments on Tokamak Fusion Test reactor (TFTR) and full scale fusion alphas physics studies. Fusion research in recent years has been influenced by EP physics in many ways including the limitations imposed by the "sea" of Alfven eigenmodes (AE) in particular by the toroidicityinduced AEsmore » (TAE) modes and reversed shear Alfven (RSAE). In present paper we attempt a broad review of EP physics progress in tokamaks and spherical tori since the first DT experiments on TFTR and JET (Joint European Torus) including helical/stellarator devices. Introductory discussions on basic ingredients of EP physics, i.e. particle orbits in STs, fundamental diagnostic techniques of EPs and instabilities, wave particle resonances and others are given to help understanding the advanced topics of EP physics. At the end we cover important and interesting physics issues toward the burning plasma experiments such as ITER (International Thermonuclear Experimental Reactor).« less
Acoustic emission characterization of microcracking in laboratory-scale hydraulic fracturing tests
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hampton, Jesse; Gutierrez, Marte; Matzar, Luis
Understanding microcracking near coalesced fracture generation is critically important for hydrocarbon and geothermal reservoir characterization as well as damage evaluation in civil engineering structures. Dense and sometimes random microcracking near coalesced fracture formation alters the mechanical properties of the nearby virgin material. Individual microcrack characterization is also significant in quantifying the material changes near the fracture faces (i.e. damage). Acoustic emission (AE) monitoring and analysis provide unique information regarding the microcracking process temporally, and information concerning the source characterization of individual microcracks can be extracted. In this context, laboratory hydraulic fracture tests were carried out while monitoring the AEs frommore » several piezoelectric transducers. In-depth post-processing of the AE event data was performed for the purpose of understanding the individual source mechanisms. Several source characterization techniques including moment tensor inversion, event parametric analysis, and volumetric deformation analysis were adopted. Post-test fracture characterization through coring, slicing and micro-computed tomographic imaging was performed to determine the coalesced fracture location and structure. Distinct differences in fracture characteristics were found spatially in relation to the openhole injection interval. Individual microcrack AE analysis showed substantial energy reduction emanating spatially from the injection interval. Lastly, it was quantitatively observed that the recorded AE signals provided sufficient information to generalize the damage radiating spatially away from the injection wellbore.« less
Acoustic emission characterization of microcracking in laboratory-scale hydraulic fracturing tests
Hampton, Jesse; Gutierrez, Marte; Matzar, Luis; ...
2018-06-11
Understanding microcracking near coalesced fracture generation is critically important for hydrocarbon and geothermal reservoir characterization as well as damage evaluation in civil engineering structures. Dense and sometimes random microcracking near coalesced fracture formation alters the mechanical properties of the nearby virgin material. Individual microcrack characterization is also significant in quantifying the material changes near the fracture faces (i.e. damage). Acoustic emission (AE) monitoring and analysis provide unique information regarding the microcracking process temporally, and information concerning the source characterization of individual microcracks can be extracted. In this context, laboratory hydraulic fracture tests were carried out while monitoring the AEs frommore » several piezoelectric transducers. In-depth post-processing of the AE event data was performed for the purpose of understanding the individual source mechanisms. Several source characterization techniques including moment tensor inversion, event parametric analysis, and volumetric deformation analysis were adopted. Post-test fracture characterization through coring, slicing and micro-computed tomographic imaging was performed to determine the coalesced fracture location and structure. Distinct differences in fracture characteristics were found spatially in relation to the openhole injection interval. Individual microcrack AE analysis showed substantial energy reduction emanating spatially from the injection interval. Lastly, it was quantitatively observed that the recorded AE signals provided sufficient information to generalize the damage radiating spatially away from the injection wellbore.« less
Ohuchi, Shoji J; Sagawa, Fumihiko; Sakamoto, Taiichi; Inoue, Tan
2015-10-23
RNA-protein complexes (RNPs) are useful for constructing functional nano-objects because a variety of functional proteins can be displayed on a designed RNA scaffold. Here, we report circular permutations of an RNA-binding protein L7Ae based on the three-dimensional structure information to alter the orientation of the displayed proteins on the RNA scaffold. An electrophoretic mobility shift assay and atomic force microscopy (AFM) analysis revealed that most of the designed circular permutants formed an RNP nano-object. Moreover, the alteration of the enhanced green fluorescent protein (EGFP) orientation was confirmed with AFM by employing EGFP on the L7Ae permutant on the RNA. The results demonstrate that targeted fine-tuning of the stereo-specific fixation of a protein on a protein-binding RNA is feasible by using the circular permutation technique. Copyright © 2015 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Abdul Hakeem, Z.; Noorsuhada, M. N.; Azmi, I.; Noor Syafeekha, M. S.; Soffian Noor, M. S.
2017-12-01
In this study, steel fibre reinforced concrete (SFRC) beams strengthened with carbon fibre reinforced polymer (CFRP) were investigated using acoustic emission (AE) technique. Three beams with dimension of 150 mm width, 200 mm depth and 1500 mm length were fabricated. The results generated from AE parameters were analysed as well as signal strength and cumulative signal strength. Three relationships were produced namely load versus deflection, signal strength versus time and cumulative signal strength with respect to time. Each relationship indicates significant physical behaviour as the crack propagated in the beams. It is found that an addition of steel fibre in the concrete mix and strengthening of CFRP increase the ultimate load of the beam and the activity of signal strength. Moreover, the highest signal strength generated can be identified. From the study, the occurrence of crack in the beam can be predicted using AE signal strength.
NASA Technical Reports Server (NTRS)
Brainard, W. A.; Ferrante, J.
1979-01-01
The wear of pure iron in sliding contact with hardened M-2 tool steel was measured for a series of synthetic diester fluids, both with and without a zinc dialkyl dithiophosphate (ZDP) antiwear additive, as test lubricants. Selected wear scars were analyzed by an Auger emission spectroscopy (AES) depth profiling technique in order to assess the surface film elemental composition. The ZDP was an effective antiwear additive for all the diesters except dibutyl oxalate and dibutyl sebacate. The high wear measured for the additive-containing oxalate was related to corrosion; the higher wear measured for the additive-containing sebacate was due to an oxygen interaction. The AES of dibutyl sebacate surfaces run in dry air and in dry nitrogen showed large differences only in the amount of oxygen present. The AES of worn surfaces where the additive was effective showed no zinc, only a little phosphorus, and large amounts of sulfur.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ohuchi, Shoji J.; Sagawa, Fumihiko; Sakamoto, Taiichi
RNA-protein complexes (RNPs) are useful for constructing functional nano-objects because a variety of functional proteins can be displayed on a designed RNA scaffold. Here, we report circular permutations of an RNA-binding protein L7Ae based on the three-dimensional structure information to alter the orientation of the displayed proteins on the RNA scaffold. An electrophoretic mobility shift assay and atomic force microscopy (AFM) analysis revealed that most of the designed circular permutants formed an RNP nano-object. Moreover, the alteration of the enhanced green fluorescent protein (EGFP) orientation was confirmed with AFM by employing EGFP on the L7Ae permutant on the RNA. Themore » results demonstrate that targeted fine-tuning of the stereo-specific fixation of a protein on a protein-binding RNA is feasible by using the circular permutation technique.« less
NASA Astrophysics Data System (ADS)
Rahmani, A.; Benyaïch, F.; Bounakhla, M.; Bilal, E.; Moutte, J.; Gruffat, J. J.; Zahry, F.
2004-11-01
Dans ce travail, nous présentons une étude comparative des techniques d'analyse par fluorescence X à dispersion d'énergie (ED-XRF) et à dispersion de longueur d'onde (WD-XRF), et par spectrométrie d'émission atomique à source plasma couplée par induction (ICP-AES). Les résultats de la calibration des spectromètres à dispersion d'énergie, à excitation par sources radioactives (55Fe, 109Cd et 241Am) et à excitation secondaire (cible secondaire Mo et Cu) du Centre National pour l'Energie, les Sciences et les Techniques Nucléaires (CNESTEN, Rabat, Maroc) sur des échantillons étalons de références de l'Agence International de l'Energie Atomique (AIEA) et du Community Bureau of Référence (BCR) ont été comparés aux résultats d'analyse des mêmes échantillons étalons par la spectrométrie X à dispersion de longueur d'onde (WD-XRF) et par spectrométrie d'émission atomique à source plasma couplé par induction (ICP-AES) au département GENERIC du centre SPIN à l'Ecole des Mines de Saint-Etienne (France). Les trois techniques d'analyse utilisées donnent des résultats comparables pour le dosage des éléments majeurs, alors que pour les traces on note des déviations importantes à cause des effets de matrice qui sont difficiles à corriger dans le cas de la fluorescence X.
Low-dimensional chaos in magnetospheric activity from AE time series
NASA Technical Reports Server (NTRS)
Vassiliadis, D. V.; Sharma, A. S.; Eastman, T. E.; Papadopoulos, K.
1990-01-01
The magnetospheric response to the solar-wind input, as represented by the time-series measurements of the auroral electrojet (AE) index, has been examined using phase-space reconstruction techniques. The system was found to behave as a low-dimensional chaotic system with a fractal dimension of 3.6 and has Kolmogorov entropy less than 0.2/min. These indicate that the dynamics of the system can be adequately described by four independent variables, and that the corresponding intrinsic time scale is of the order of 5 min. The relevance of the results to magnetospheric modeling is discussed.
Bouslimi, D; Coatrieux, G; Roux, Ch
2011-01-01
In this paper, we propose a new joint watermarking/encryption algorithm for the purpose of verifying the reliability of medical images in both encrypted and spatial domains. It combines a substitutive watermarking algorithm, the quantization index modulation (QIM), with a block cipher algorithm, the Advanced Encryption Standard (AES), in CBC mode of operation. The proposed solution gives access to the outcomes of the image integrity and of its origins even though the image is stored encrypted. Experimental results achieved on 8 bits encoded Ultrasound images illustrate the overall performances of the proposed scheme. By making use of the AES block cipher in CBC mode, the proposed solution is compliant with or transparent to the DICOM standard.
A pipelined FPGA implementation of an encryption algorithm based on genetic algorithm
NASA Astrophysics Data System (ADS)
Thirer, Nonel
2013-05-01
With the evolution of digital data storage and exchange, it is essential to protect the confidential information from every unauthorized access. High performance encryption algorithms were developed and implemented by software and hardware. Also many methods to attack the cipher text were developed. In the last years, the genetic algorithm has gained much interest in cryptanalysis of cipher texts and also in encryption ciphers. This paper analyses the possibility to use the genetic algorithm as a multiple key sequence generator for an AES (Advanced Encryption Standard) cryptographic system, and also to use a three stages pipeline (with four main blocks: Input data, AES Core, Key generator, Output data) to provide a fast encryption and storage/transmission of a large amount of data.
Pollett, S; Melendrez, M C; Maljkovic Berry, I; Duchêne, S; Salje, H; Dat, Cummings; Jarman, R G
2018-04-25
Dengue virus (DENV) causes a profound burden of morbidity and mortality, and its global burden is rising due to the co-circulation of four divergent DENV serotypes in the ecological context of globalization, travel, climate change, urbanization, and expansion of the geographic range of the Ae.aegypti and Ae.albopictus vectors. Understanding DENV evolution offers valuable opportunities to enhance surveillance and response to DENV epidemics via advances in RNA virus sequencing, bioinformatics, phylogenetic and other computational biology methods. Here we provide a scoping overview of the evolution and molecular epidemiology of DENV and the range of ways that evolutionary analyses can be applied as a public health tool against this arboviral pathogen. Copyright © 2018. Published by Elsevier B.V.
2012-08-03
CAPE CANAVERAL, Fla. – Inside the Space Life Sciences Laboratory, or SLSL, at NASA’s Kennedy Space Center in Florida, radish plants are being harvested in a plant growth chamber. The plants were grown under red and blue LED lights. The plant experiment at Kennedy is part of the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. This plant experiment studies the effects of different types of lighting on plants such as radishes and leaf lettuce. Results of these studies will help provide information on how to grow food sources for deep space exploration missions. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. Photo credit: NASA/Frank Ochoa-Gonzales
2012-08-03
CAPE CANAVERAL, Fla. – Inside the Space Life Sciences Laboratory, or SLSL, at NASA’s Kennedy Space Center in Florida, radish plants were harvested from a plant growth chamber. The plants were grown under red and blue LED lights. The plant experiment at Kennedy is part of the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. This plant experiment studies the effects of different types of lighting on plants such as radishes and leaf lettuce. Results of these studies will help provide information on how to grow food sources for deep space exploration missions. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. Photo credit: NASA/Frank Ochoa-Gonzales
DOE Office of Scientific and Technical Information (OSTI.GOV)
Westover, Kenneth D.; Loo, Billy W.; Gerber, David E.
2015-09-01
Purpose: Treatment regimens for locally advanced non-small cell lung cancer (NSCLC) give suboptimal clinical outcomes. Technological advancements such as radiation therapy, the backbone of most treatment regimens, may enable more potent and effective therapies. The objective of this study was to escalate radiation therapy to a tumoricidal hypofractionated dose without exceeding the maximally tolerated dose (MTD) in patients with locally advanced NSCLC. Methods and Materials: Patients with stage II to IV or recurrent NSCLC and Eastern Cooperative Oncology Group performance status of 2 or greater and not candidates for surgical resection, stereotactic radiation, or concurrent chemoradiation were eligible. Highly conformal radiationmore » therapy was given to treat intrathoracic disease in 15 fractions to a total of 50, 55, or 60 Gy. Results: Fifty-five patients were enrolled: 15 at the 50-Gy, 21 at the 55-Gy, and 19 at the 60-Gy dose levels. A 90-day follow-up was completed in each group without exceeding the MTD. With a median follow-up of 12.5 months, there were 93 grade ≥3 adverse events (AEs), including 39 deaths, although most AEs were considered related to factors other than radiation therapy. One patient from the 55- and 60-Gy dose groups developed grade ≥3 esophagitis, and 5, 4, and 4 patients in the respective dose groups experienced grade ≥3 dyspnea, but only 2 of these AEs were considered likely related to therapy. There was no association between fraction size and toxicity (P=.24). The median overall survival was 6 months with no significant differences between dose levels (P=.59). Conclusions: Precision hypofractionated radiation therapy consisting of 60 Gy in 15 fractions for locally advanced NSCLC is generally well tolerated. This treatment regimen could provide patients with poor performance status a potent alternative to chemoradiation. This study has implications for the cost effectiveness of lung cancer therapy. Additional studies of long-term safety and efficacy of this therapy are warranted.« less
Nawabi, Danyal H.; Jones, Kristofer J.; Lurie, Brett; Potter, Hollis G.; Green, Daniel W.; Cordasco, Frank A.
2013-01-01
Objectives: The decision to perform anterior cruciate ligament (ACL) reconstruction in skeletally immature patients carries a risk of growth disturbance due to iatrogenic physeal injury. Multiple physeal-sparing techniques have been described but none, to our knowledge combine the benefits of an anatomic reconstruction and socket fixation, without violation of either the femoral or tibial physis at any stage of the procedure. The purpose of this study was to compare the incidence and calculate the area of post-operative physeal disturbances, using a physeal-sensitive magnetic resonance imaging (MRI) sequence*, between all-epiphyseal (AE) and partial transphyseal (PTP) ACL reconstructions in a cohort of skeletally-immature patients. Methods: Twenty-one skeletally immature patients with a mean chronologic age of 12.7 years (range 10 to 16) undergoing all-inside ACL reconstruction were prospectively followed. Fourteen patients had an all-epiphyseal (AE) ACL reconstruction and 7 patients had a partial transphyseal (PTP) ACL reconstruction, which spared the femoral physis but crossed the tibial physis. Hamstring autograft was used in all cases. At a mean of 11.6 months follow-up, all patients were assessed for focal physeal disturbance and graft survival using a three-dimensional (3D) fat suppressed spoiled gradient-recalled echo (SPGR) MRI sequence. Angular deformity and leg length discrepancy were evaluated on full-length standing radiographs. The International Knee Documentation Committee (IKDC) subjective score and Lysholm knee score were also documented. Results: The tibial physis was violated in 13/14 patients in the AE group and all patients in the PTP group. The mean area of post-operative tibial physeal disturbance (± SD) was 42.4 ± 38.6 mm2 (mean 1.7% of total physeal area) in the AE group compared to 216.7 ± 129.1 mm2 (mean 7.3% of total physeal area) in the PTP group (p = 0.003). The femoral physis was violated in one case in both groups resulting in a mean physeal disturbance of 1.5% of the total distal femoral physeal area. No cases of fracture, articular surface violation or avascular necrosis were noted on MRI in either group. Short-term graft survival was 100% amongst the entire cohort. There were no cases of angular deformity in either group with a mean side-side difference in the lateral distal femoral angle of 1.11° ± 1.02° in the AE group and 0.72° ± 0.65° in the PTP group (p = 0.23). No significant leg-length discrepancies were measured in either group. The mean IKDC and Lysholm scores (± SD) were 93.3 ± 5.9 and 97.8 ± 3.8 respectively in the AE group and 87.7 ± 3.5 and 96 ± 5.2 respectively in the PTP group. Conclusion: All-epiphyseal ACL reconstruction caused significantly less focal physeal disturbance than PTP ACL reconstruction, as determined by a 3D physeal-sensitive MRI sequence. Neither technique however resulted in angular deformity or leg-length discrepancy at early follow-up. Both all-inside ACL reconstruction techniques used in this study are safe and effective at early follow-up in skeletally immature patients. Further longitudinal study of this cohort is required to determine any potential advantages of a purely physeal-sparing technique.
Advanced Computing Methods for Knowledge Discovery and Prognosis in Acoustic Emission Monitoring
ERIC Educational Resources Information Center
Mejia, Felipe
2012-01-01
Structural health monitoring (SHM) has gained significant popularity in the last decade. This growing interest, coupled with new sensing technologies, has resulted in an overwhelming amount of data in need of management and useful interpretation. Acoustic emission (AE) testing has been particularly fraught by the problem of growing data and is…
Predicting Alumni/ae Gift Giving Behavior: A Structural Equation Model Approach.
ERIC Educational Resources Information Center
Mosser, John Wayne
This dissertation focuses on predicting alumni gift giving behavior at a large public research university (University of Michigan). A conceptual model was developed for predicting alumni giving behavior in order to advance the theoretical understanding of how capacity to give, motivation to give, and their interaction effect gift giving behavior.…
NASA Technical Reports Server (NTRS)
Paliwoda, L.
1998-01-01
This document contains the procedure and the test results of the Advanced Microwave Sounding Unit-A (AMSU-A) Earth Observing System (EOS) Project, assembly part number 1356008-1, serial number 202, Electromagnetic Interference (EMI) and Electromagnetic Susceptibility (EMC) qualification test. The test was conducted in accordance with the approved EMI/EMC Test Plan/Procedure, Specification number AE-26151/8B, dated 10 September 1998. Aerojet intends that the presentation and submittal of this document, prepared in accordance with the objectives established by the aforementioned Test Plan/Procedure, document number AE-26151/8B, will satisfy the data requirement with respect to the AMSU-A/EOS instrument operational compliance of the EMI/EMC test requirement. Test for the AMSU-A/EOS instrument have been completed and all the requirements per General Interface Requirement Document (GIRD), GSFC 422-11-12-01, for EOS Common Spacecraft/Instruments, paragraph 10.11, were met with the exceptions of the test methods CE03, RE01, and RE02, as described in this document.
Dynamic neutral beam current and voltage control to improve beam efficacy in tokamaks
NASA Astrophysics Data System (ADS)
Pace, D. C.; Austin, M. E.; Bardoczi, L.; Collins, C. S.; Crowley, B.; Davis, E.; Du, X.; Ferron, J.; Grierson, B. A.; Heidbrink, W. W.; Holcomb, C. T.; McKee, G. R.; Pawley, C.; Petty, C. C.; Podestà, M.; Rauch, J.; Scoville, J. T.; Spong, D. A.; Thome, K. E.; Van Zeeland, M. A.; Varela, J.; Victor, B.
2018-05-01
An engineering upgrade to the neutral beam system at the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] enables time-dependent programming of the beam voltage and current. Initial application of this capability involves pre-programmed beam voltage and current injected into plasmas that are known to be susceptible to instabilities that are driven by energetic ( E ≥ 40 keV) beam ions. These instabilities, here all Alfvén eigenmodes (AEs), increase the transport of the beam ions beyond a classical expectation based on particle drifts and collisions. Injecting neutral beam power, P beam ≥ 2 MW, at reduced voltage with increased current reduces the drive for Alfvénic instabilities and results in improved ion confinement. In lower-confinement plasmas, this technique is applied to eliminate the presence of AEs across the mid-radius of the plasmas. Simulations of those plasmas indicate that the mode drive is decreased and the radial extent of the remaining modes is reduced compared to a higher beam voltage case. In higher-confinement plasmas, this technique reduces AE activity in the far edge and results in an interesting scenario of beam current drive improving as the beam voltage reduces from 80 kV to 65 kV.
Dynamic neutral beam current and voltage control to improve beam efficacy in tokamaks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Austin, Max E.; Bardoczi, Laszlo; Collins, Cami S.
Here, an engineering upgrade to the neutral beam system at the DIII-D tokamak enables time-dependent programming of the beam voltage and current. Initial application of this capability involves pre-programmed beam voltage and current injected into plasmas that are known to be susceptible to instabilities that are driven by energetic (E ≥ 40 keV) beam ions. These instabilities, here all Alfvén eigenmodes (AEs), increase the transport of the beam ions beyond a classical expectation based on particle drifts and collisions. Injecting neutral beam power, P beam ≥ 2MW, at reduced voltage with increased current reduces the drive for Alfvénic instabilities andmore » results in improved ion confinement. In lower-confinement plasmas, this technique is applied to eliminate the presence of AEs across the mid-radius of the plasmas. Simulations of those plasmas indicate that the mode drive is decreased and the radial extent of the remaining modes is reduced compared to a higher beam voltage case. In higher-confinement plasmas, this technique reduces AE activity in the far edge and results in an interesting scenario of beam current drive improving as the beam voltage reduces from 80 kV to 65 kV.« less
Dynamic neutral beam current and voltage control to improve beam efficacy in tokamaks
Austin, Max E.; Bardoczi, Laszlo; Collins, Cami S.; ...
2018-04-20
Here, an engineering upgrade to the neutral beam system at the DIII-D tokamak enables time-dependent programming of the beam voltage and current. Initial application of this capability involves pre-programmed beam voltage and current injected into plasmas that are known to be susceptible to instabilities that are driven by energetic (E ≥ 40 keV) beam ions. These instabilities, here all Alfvén eigenmodes (AEs), increase the transport of the beam ions beyond a classical expectation based on particle drifts and collisions. Injecting neutral beam power, P beam ≥ 2MW, at reduced voltage with increased current reduces the drive for Alfvénic instabilities andmore » results in improved ion confinement. In lower-confinement plasmas, this technique is applied to eliminate the presence of AEs across the mid-radius of the plasmas. Simulations of those plasmas indicate that the mode drive is decreased and the radial extent of the remaining modes is reduced compared to a higher beam voltage case. In higher-confinement plasmas, this technique reduces AE activity in the far edge and results in an interesting scenario of beam current drive improving as the beam voltage reduces from 80 kV to 65 kV.« less
Park, Joung-Man; Kim, Dae-Sik; Kim, Sung-Ryong
2003-08-15
Comparison of interfacial properties and microfailure mechanisms of oxygen-plasma treated poly(p-phenylene-2,6-benzobisoxazole (PBO, Zylon) and poly(p-phenylene terephthalamide) (PPTA, Kevlar) fibers/epoxy composites were investigated using a micromechanical technique and nondestructive acoustic emission (AE). The interfacial shear strength (IFSS) and work of adhesion, Wa, of PBO or Kevlar fiber/epoxy composites increased with oxygen-plasma treatment, due to induced hydrogen and covalent bondings at their interface. Plasma-treated Kevlar fiber showed the maximum critical surface tension and polar term, whereas the untreated PBO fiber showed the minimum values. The work of adhesion and the polar term were proportional to the IFSS directly for both PBO and Kevlar fibers. The microfibril fracture pattern of two plasma-treated fibers appeared obviously. Unlike in slow cooling, in rapid cooling, case kink band and kicking in PBO fiber appeared, whereas buckling in the Kevlar fiber was observed mainly due to compressive and residual stresses. Based on the propagation of microfibril failure toward the core region, the number of AE events for plasma-treated PBO and Kevlar fibers increased significantly compared to the untreated case. The results of nondestructive AE were consistent with microfailure modes.
Cradle-to-Grave Logistic Technologies for Exploration Missions
NASA Technical Reports Server (NTRS)
Broyan, James L.; Ewert, Michael K.; Shull, Sarah
2013-01-01
Human exploration missions under study are very limited by the launch mass capacity of exiting and planned vehicles. The logistical mass of crew items is typically considered separate from the vehicle structure, habitat outfitting, and life support systems. Consequently, crew item logistical mass is typically competing with vehicle systems for mass allocation. NASA is Advanced Exploration Systems (AES) Logistics Reduction and Repurposing (LRR) Project is developing four logistics technologies guided by a systems engineering cradle-to-grave approach to enable used crew items to augment vehicle systems. Specifically, AES LRR is investigating the direct reduction of clothing mass, the repurposing of logistical packaging, the processing of spent crew items to benefit radiation shielding and water recovery, and the conversion of trash to propulsion supply gases. The systematic implementation of these types of technologies will increase launch mass efficiency by enabling items to be used for secondary purposes and improve the habitability of the vehicle as the mission duration increases. This paper provides a description, benefits, and challenges of the four technologies under development and a status of progress at the mid ]point of the three year AES project.
Yang, Y R; Craig, P S; Ito, A; Vuitton, D A; Giraudoux, P; Sun, T; Williams, G M; Huang, Z; Li, Z; Wang, Y; Teng, J; Li, Y; Huang, L; Wen, H; Jones, M K; McManus, D P
2007-05-01
We correlated ultrasound (US) imaging classifications for human alveolar echinococcosis (AE) and cystic echinococcosis (CE) with serology (ELISA and immunoblotting (IB) incorporating native and recombinant/purified echinococcal antigens) in community surveys (2001-2003) and follow-up (2002 and 2003) of US-confirmed cases in Ningxia, China. One hundred and seventy-one cases (96 with AE, 75 with CE) were identified; of these, US classification and serological data were obtained for 142 and 112 cases, respectively. Seropositive-rates increased in CE patients with highly viable unilocular cyst lesions (Types CL, CE 1 or CE 2) to degenerating primary lesions (CE 3), but then decreased in subjects with inactive (CE 4) or dead (CE 5) cysts. In contrast, there was a constant increase in seropositivity from the early (P1, P2) to the advanced stages (P3, P4) with AE cases. For US-confirmed cases, follow-up by US combined with serology is invaluable for studying the clinical progression of echinococcosis and for detecting recurrent cysts or reinfection post-treatment.
Gangadari, Bhoopal Rao; Rafi Ahamed, Shaik
2016-09-01
In biomedical, data security is the most expensive resource for wireless body area network applications. Cryptographic algorithms are used in order to protect the information against unauthorised access. Advanced encryption standard (AES) cryptographic algorithm plays a vital role in telemedicine applications. The authors propose a novel approach for design of substitution bytes (S-Box) using second-order reversible one-dimensional cellular automata (RCA 2 ) as a replacement to the classical look-up-table (LUT) based S-Box used in AES algorithm. The performance of proposed RCA 2 based S-Box and conventional LUT based S-Box is evaluated in terms of security using the cryptographic properties such as the nonlinearity, correlation immunity bias, strict avalanche criteria and entropy. Moreover, it is also shown that RCA 2 based S-Boxes are dynamic in nature, invertible and provide high level of security. Further, it is also found that the RCA 2 based S-Box have comparatively better performance than that of conventional LUT based S-Box.
Rafi Ahamed, Shaik
2016-01-01
In biomedical, data security is the most expensive resource for wireless body area network applications. Cryptographic algorithms are used in order to protect the information against unauthorised access. Advanced encryption standard (AES) cryptographic algorithm plays a vital role in telemedicine applications. The authors propose a novel approach for design of substitution bytes (S-Box) using second-order reversible one-dimensional cellular automata (RCA2) as a replacement to the classical look-up-table (LUT) based S-Box used in AES algorithm. The performance of proposed RCA2 based S-Box and conventional LUT based S-Box is evaluated in terms of security using the cryptographic properties such as the nonlinearity, correlation immunity bias, strict avalanche criteria and entropy. Moreover, it is also shown that RCA2 based S-Boxes are dynamic in nature, invertible and provide high level of security. Further, it is also found that the RCA2 based S-Box have comparatively better performance than that of conventional LUT based S-Box. PMID:27733924
Morales-Pérez, Ariadna A; Maravilla, Pablo; Solís-López, Myriam; Schouwenaars, Rafael; Durán-Moreno, Alfonso; Ramírez-Zamora, Rosa-María
2016-01-01
An experimental design methodology was used to optimize the synthesis of an iron-supported nanocatalyst as well as the inactivation process of Ascaris eggs (Ae) using this material. A factor screening design was used for identifying the significant experimental factors for nanocatalyst support (supported %Fe, (w/w), temperature and time of calcination) and for the inactivation process called the heterogeneous Fenton-like reaction (H2O2 dose, mass ratio Fe/H2O2, pH and reaction time). The optimization of the significant factors was carried out using a face-centered central composite design. The optimal operating conditions for both processes were estimated with a statistical model and implemented experimentally with five replicates. The predicted value of the Ae inactivation rate was close to the laboratory results. At the optimal operating conditions of the nanocatalyst production and Ae inactivation process, the Ascaris ova showed genomic damage to the point that no cell reparation was possible showing that this advanced oxidation process was highly efficient for inactivating this pathogen.
Wetting characteristic of ceramic to water and adhesive resin.
Oh, Won-Suck; Shen, Chiayi; Alegre, Brandon; Anusavice, Kenneth J
2002-12-01
Maximum wetting of ceramic by adhesive resin is required to achieve optimal adhesion of the resin to ceramic. It is unknown whether the adhesion of the resin to the ceramic is affected by the surface topography and wetting by water or the adhesive resin. This study was designed to characterize the effect of surface topography on the wetting of ceramics by water and adhesive resin. Three materials, a veneering ceramic, Eris (ERV), and 2 core ceramics, Empress 1 core ceramic (E1C) and an experimental core ceramic (EXC), were used. Four surface-roughening procedures were used. They included polishing through 1200-grit SiC paper (P), air abrasion with 50 microm Al(2)O(3) (A), etching with 5% hydrofluoric acid gel (E), and a combination of airborne particle abrasion and etching (A/E). Forty bar specimens (15 x 10 x 1.5 mm) were prepared from each material (N=120). Twelve groups of 10 specimens each were prepared for the 4 surface-roughening procedures. Advancing (theta(A)) and receding (theta(R)) contact angles were measured with a CAHN Dynamic Contact Analyzer, on the basis of the Wilhelmy plate technique, with water and adhesive resin. The work of adhesion (W(A)) by the probing media was calculated by use of advancing contact angle data. The data were analyzed by t testing, analysis of variance, and Duncan's tests (alpha=0.05) to determine the statistical significance of differences in the contact angles between ceramic and water or resin as a function of surface roughening. In general, the mean theta(A) values were higher than the mean theta(R) values except for groups of E or A/E specimens with water used as a probing medium. E and A/E treatments yielded the lowest contact angle values, followed by A and P treatments (P<.001). The E1C exhibited the highest mean contact angles, whereas EXC exhibited the lowest mean contact angle except for the theta(R) with resin. The corresponding values for ERV were between those of E1C and EXC except for theta(R) values with resin. The resin medium yielded higher mean contact angles than the water medium for the same surfaces. W(A) ranged from 62.9 to 145.2 mJ/m(2). Within the limitations of this study, etching or a combination of air abrasion and etching were comparably effective in increasing the surface area for bonding. The most wettable surface as measured by the resin medium was EXC, followed by ERV and E1C.
Advanced Clinical Decision Support for Vaccine Adverse Event Detection and Reporting.
Baker, Meghan A; Kaelber, David C; Bar-Shain, David S; Moro, Pedro L; Zambarano, Bob; Mazza, Megan; Garcia, Crystal; Henry, Adam; Platt, Richard; Klompas, Michael
2015-09-15
Reporting of adverse events (AEs) following vaccination can help identify rare or unexpected complications of immunizations and aid in characterizing potential vaccine safety signals. We developed an open-source, generalizable clinical decision support system called Electronic Support for Public Health-Vaccine Adverse Event Reporting System (ESP-VAERS) to assist clinicians with AE detection and reporting. ESP-VAERS monitors patients' electronic health records for new diagnoses, changes in laboratory values, and new allergies following vaccinations. When suggestive events are found, ESP-VAERS sends the patient's clinician a secure electronic message with an invitation to affirm or refute the message, add comments, and submit an automated, prepopulated electronic report to VAERS. High-probability AEs are reported automatically if the clinician does not respond. We implemented ESP-VAERS in December 2012 throughout the MetroHealth System, an integrated healthcare system in Ohio. We queried the VAERS database to determine MetroHealth's baseline reporting rates from January 2009 to March 2012 and then assessed changes in reporting rates with ESP-VAERS. In the 8 months following implementation, 91 622 vaccinations were given. ESP-VAERS sent 1385 messages to responsible clinicians describing potential AEs. Clinicians opened 1304 (94.2%) messages, responded to 209 (15.1%), and confirmed 16 for transmission to VAERS. An additional 16 high-probability AEs were sent automatically. Reported events included seizure, pleural effusion, and lymphocytopenia. The odds of a VAERS report submission during the implementation period were 30.2 (95% confidence interval, 9.52-95.5) times greater than the odds during the comparable preimplementation period. An open-source, electronic health record-based clinical decision support system can increase AE detection and reporting rates in VAERS. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
NASA Technical Reports Server (NTRS)
Gardner, Kevin D.; Liu, Jong-Shang; Murthy, Durbha V.; Kruse, Marlin J.; James, Darrell
1999-01-01
AlliedSignal Engines, in cooperation with NASA GRC (National Aeronautics and Space Administration Glenn Research Center), completed an evaluation of recently-developed aeroelastic computer codes using test cases from the AlliedSignal Engines fan blisk and turbine databases. Test data included strain gage, performance, and steady-state pressure information obtained for conditions where synchronous or flutter vibratory conditions were found to occur. Aeroelastic codes evaluated included quasi 3-D UNSFLO (MIT Developed/AE Modified, Quasi 3-D Aeroelastic Computer Code), 2-D FREPS (NASA-Developed Forced Response Prediction System Aeroelastic Computer Code), and 3-D TURBO-AE (NASA/Mississippi State University Developed 3-D Aeroelastic Computer Code). Unsteady pressure predictions for the turbine test case were used to evaluate the forced response prediction capabilities of each of the three aeroelastic codes. Additionally, one of the fan flutter cases was evaluated using TURBO-AE. The UNSFLO and FREPS evaluation predictions showed good agreement with the experimental test data trends, but quantitative improvements are needed. UNSFLO over-predicted turbine blade response reductions, while FREPS under-predicted them. The inviscid TURBO-AE turbine analysis predicted no discernible blade response reduction, indicating the necessity of including viscous effects for this test case. For the TURBO-AE fan blisk test case, significant effort was expended getting the viscous version of the code to give converged steady flow solutions for the transonic flow conditions. Once converged, the steady solutions provided an excellent match with test data and the calibrated DAWES (AlliedSignal 3-D Viscous Steady Flow CFD Solver). However, efforts expended establishing quality steady-state solutions prevented exercising the unsteady portion of the TURBO-AE code during the present program. AlliedSignal recommends that unsteady pressure measurement data be obtained for both test cases examined for use in aeroelastic code validation.
Wear detection by means of wavelet-based acoustic emission analysis
NASA Astrophysics Data System (ADS)
Baccar, D.; Söffker, D.
2015-08-01
Wear detection and monitoring during operation are complex and difficult tasks especially for materials under sliding conditions. Due to the permanent contact and repetitive motion, the material surface remains during tests non-accessible for optical inspection so that attrition of the contact partners cannot be easily detected. This paper introduces the relevant scientific components of reliable and efficient condition monitoring system for online detection and automated classification of wear phenomena by means of acoustic emission (AE) and advanced signal processing approaches. The related experiments were performed using a tribological system consisting of two martensitic plates, sliding against each other. High sensitive piezoelectric transducer was used to provide the continuous measurement of AE signals. The recorded AE signals were analyzed mainly by time-frequency analysis. A feature extraction module using a novel combination of Short-Time Fourier Transform (STFT) and Continuous Wavelet Transform (CWT) were used for the first time. A detailed correlation analysis between complex signal characteristics and the surface damage resulting from contact fatigue was investigated. Three wear process stages were detected and could be distinguished. To obtain quantitative and detailed information about different wear phases, the AE energy was calculated using STFT and decomposed into a suitable number of frequency levels. The individual energy distribution and the cumulative AE energy of each frequency components were analyzed using CWT. Results show that the behavior of individual frequency component changes when the wear state changes. Here, specific frequency ranges are attributed to the different wear states. The study reveals that the application of the STFT-/CWT-based AE analysis is an appropriate approach to distinguish and to interpret the different damage states occurred during sliding contact. Based on this results a new generation of condition monitoring systems can be build, able to evaluate automatically the surface condition of machine components with sliding surfaces.
NASA Technical Reports Server (NTRS)
Parker, Bradford H.
1992-01-01
An acoustic emission (AE) system was set up in a linear location data acquisition mode to monitor the tensile loading of eight-ply quasi-isotropic graphite/epoxy specimens containing low velocity impact damage. The impact damage was induced using an instrumented drop weight tower. During impact, specimens were supported by either an aluminum plate or a membrane configuration. Cross-sectional examinations revealed that the aluminum plate configuration resulted in primarily matrix cracking and back surface fiber failure. The membrane support resulted in only matrix cracking and delamination damage. Penetrant enhanced radiography and immersion ultrasonics were used in order to assess the amount of impact damage in each tensile specimen. During tensile loading, AE reliably detected and located the damage sites which included fiber failure. All specimens with areas of fiber breakage ultimately failed at the impact site. AE did not reliably locate damage which consisted of only delaminations and matrix cracking. Specimens with this type of damage did not ultimately fail at the impact site. In summary, AE demonstrated the ability to increase the reliability of structural proof tests; however, the successful use of this technique requires extensive baseline testing.
NASA Astrophysics Data System (ADS)
Guarnieri, Fernando L.; Tsurutani, Bruce T.; Vieira, Luis E. A.; Hajra, Rajkumar; Echer, Ezequiel; Mannucci, Anthony J.; Gonzalez, Walter D.
2018-01-01
The purpose of this study is to present a wavelet interactive filtering and reconstruction technique and apply this to the solar wind magnetic field components detected at the L1 Lagrange point ˜ 0.01 AU upstream of the Earth. These filtered interplanetary magnetic field (IMF) data are fed into a model to calculate a time series which we call AE∗. This model was adjusted assuming that magnetic reconnection associated with southward-directed IMF Bz is the main mechanism transferring energy into the magnetosphere. The calculated AE∗ was compared to the observed AE (auroral electrojet) index using cross-correlation analysis. The results show correlations as high as 0.90. Empirical removal of the high-frequency, short-wavelength Alfvénic component in the IMF by wavelet decomposition is shown to dramatically improve the correlation between AE∗ and the observed AE index. It is envisioned that this AE∗ can be used as the main input for a model to forecast relativistic electrons in the Earth's outer radiation belts, which are delayed by ˜ 1 to 2 days from intense AE events.
Carpinteri, Alberto; Lacidogna, Giuseppe; Invernizzi, Stefano; Accornero, Federico
2013-01-01
We examine an application of Acoustic Emission (AE) technique for a probabilistic analysis in time and space of earthquakes, in order to preserve the valuable Italian Renaissance Architectural Complex named "The Sacred Mountain of Varallo." Among the forty-five chapels of the Renaissance Complex, the structure of the Chapel XVII is of particular concern due to its uncertain structural condition and due to the level of stress caused by the regional seismicity. Therefore, lifetime assessment, taking into account the evolution of damage phenomena, is necessary to preserve the reliability and safety of this masterpiece of cultural heritage. A continuous AE monitoring was performed to assess the structural behavior of the Chapel. During the monitoring period, a correlation between peaks of AE activity in the masonry of the "Sacred Mountain of Varallo" and regional seismicity was found. Although the two phenomena take place on very different scales, the AE in materials and the earthquakes in Earth's crust, belong to the same class of invariance. In addition, an accurate finite element model, performed with DIANA finite element code, is presented to describe the dynamic behavior of Chapel XVII structure, confirming visual and instrumental inspections of regional seismic effects.
Pritchard, Kathleen I; Burris, Howard A; Ito, Yoshinori; Rugo, Hope S; Dakhil, Shaker; Hortobagyi, Gabriel N; Campone, Mario; Csöszi, Tibor; Baselga, José; Puttawibul, Puttisak; Piccart, Martine; Heng, Daniel; Noguchi, Shinzaburo; Srimuninnimit, Vichien; Bourgeois, Hugues; Gonzalez Martin, Antonio; Osborne, Karen; Panneerselvam, Ashok; Taran, Tetiana; Sahmoud, Tarek; Gnant, Michael
2013-12-01
Postmenopausal women with hormone receptor-positive (HR(+)) breast cancer in whom disease progresses or there is recurrence while taking a nonsteroidal aromatase inhibitor (NSAI) are usually treated with exemestane (EXE), but no single standard of care exists in this setting. The BOLERO-2 trial demonstrated that adding everolimus (EVE) to EXE improved progression-free survival (PFS) while maintaining quality of life when compared with EXE alone. Because many women with HR(+) advanced breast cancer are elderly, the tolerability profile of EVE plus EXE in this population is of interest. BOLERO-2, a phase III randomized trial, compared EVE (10 mg/d) and placebo (PBO), both plus EXE (25 mg/d), in 724 postmenopausal women with HR(+) advanced breast cancer recurring/progressing after treatment with NSAIs. Safety and efficacy data in elderly patients are reported at 18-month median follow-up. Baseline disease characteristics and treatment histories among the elderly subsets (≥ 65 years, n = 275; ≥ 70 years, n = 164) were generally comparable with younger patients. The addition of EVE to EXE improved PFS regardless of age (hazard ratio, 0.59 [≥ 65 years] and 0.45 [≥ 70 years]). Adverse events (AEs) of special interest (all grades) that occurred more frequently with EVE than with PBO included stomatitis, infections, rash, pneumonitis, and hyperglycemia. Elderly EVE-treated patients had similar incidences of these AEs as did younger patients but had more on-treatment deaths. Adding EVE to EXE offers substantially improved PFS over EXE and was generally well tolerated in elderly patients with HR(+) advanced breast cancer. Careful monitoring and appropriate dose reductions or interruptions for AE management are recommended during treatment with EVE in this patient population. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.
Quantitative Analysis Of Acoustic Emission From Rock Fracture Experiments
NASA Astrophysics Data System (ADS)
Goodfellow, Sebastian David
This thesis aims to advance the methods of quantitative acoustic emission (AE) analysis by calibrating sensors, characterizing sources, and applying the results to solve engi- neering problems. In the first part of this thesis, we built a calibration apparatus and successfully calibrated two commercial AE sensors. The ErgoTech sensor was found to have broadband velocity sensitivity and the Panametrics V103 was sensitive to surface normal displacement. These calibration results were applied to two AE data sets from rock fracture experiments in order to characterize the sources of AE events. The first data set was from an in situ rock fracture experiment conducted at the Underground Research Laboratory (URL). The Mine-By experiment was a large scale excavation response test where both AE (10 kHz - 1 MHz) and microseismicity (MS) (1 Hz - 10 kHz) were monitored. Using the calibration information, magnitude, stress drop, dimension and energy were successfully estimated for 21 AE events recorded in the tensile region of the tunnel wall. Magnitudes were in the range -7.5 < Mw < -6.8, which is consistent with other laboratory AE results, and stress drops were within the range commonly observed for induced seismicity in the field (0.1 - 10 MPa). The second data set was AE collected during a true-triaxial deformation experiment, where the objectives were to characterize laboratory AE sources and identify issues related to moving the analysis from ideal in situ conditions to more complex laboratory conditions in terms of the ability to conduct quantitative AE analysis. We found AE magnitudes in the range -7.8 < Mw < -6.7 and as with the in situ data, stress release was within the expected range of 0.1 - 10 MPa. We identified four major challenges to quantitative analysis in the laboratory, which in- hibited our ability to study parameter scaling (M0 ∝ fc -3 scaling). These challenges were 0c (1) limited knowledge of attenuation which we proved was continuously evolving, (2) the use of a narrow frequency band for acquisition, (3) the inability to identify P and S waves given the small sample size, and (4) acquisition using a narrow amplitude range given a low signal to noise ratio. Moving forward to the final stage of this thesis, with the ability to characterize the sources of AE, we applied our method to study an engineering problem. We chose hydraulic fracturing because of its obvious importance in the future of Canadian energy production. During a hydraulic fracture treatment, whether in a lab or in the field, energy is added to the system via hydraulic pressure. The injection energy, which is on the order of 10 J in the lab and and 100 GJ in the field, is used in the creation of new fracture surface area, the radiation of elastic waves, and aseismic deformation. In the field, it has been consistently shown that the amount of induced seismic energy radiated is between 1e-7 % and 1e-3 % of the injection energy. We tested these findings by calculating the AE energy as a percentage of the injection energy and found that for eight laboratory hydraulic fracture experiments, the seismic energy ranged from 7.02e-08 % to 1.24e-04 % of the injection energy. These results support those made in the field, which concludes that seismic energy projection is a very small component of the hydraulic fracture energy budget and that the dominant energy budget term is aseismic deformation.
Myers, Tanya R; McNeil, Michael M; Ng, Carmen S; Li, Rongxia; Lewis, Paige W; Cano, Maria V
2017-03-27
Limited data are available describing the post-licensure safety of meningococcal vaccines, including Menveo®. We reviewed reports of adverse events (AEs) to the Vaccine Adverse Event Reporting System (VAERS) to assess safety in all age groups. VAERS is a national spontaneous vaccine safety surveillance system co-administered by the Centers for Disease Control and Prevention and the US Food and Drug Administration. We searched the VAERS database for US reports of adverse events in persons who received Menveo from 1 January 2010 through 31 December 2015. We clinically reviewed reports and available medical records for serious AEs, selected pre-specified outcomes, and vaccination during pregnancy. We used empirical Bayesian data mining to identify AEs that were disproportionately reported after receipt of Menveo. During the study period, VAERS received 2614 US reports after receipt of Menveo. Of these, 67 were classified as serious, including 1 report of death. Adolescents (aged 11-18years) accounted for 74% of reports. Most of the reported AEs were non-serious and described AEs consistent with data from pre-licensure studies. Anaphylaxis and syncope were the two most common events in the serious reports. We did not identify any new safety concerns after review of AEs that exceeded the data mining threshold, although we did observe disproportionate reporting for terms that were not associated with an adverse event (e.g., "incorrect drug dosage form administered", "wrong technique in drug usage process"). Although reports were limited, we did not find any evidence for concern regarding the use of Menveo during pregnancy. In our review of VAERS reports, findings of AEs were consistent with the data from pre-licensure studies. Vaccine providers should continue to emphasize and adhere to proper administration of the vaccine. Copyright © 2017 Elsevier Ltd. All rights reserved.
An acoustic emission study on interfacial debonding in composite restorations.
Liu, Xiaozhou; Li, Haiyan; Li, Jianying; Lu, Peijun; Fok, Alex Siu-Lun
2011-09-01
This paper studied in vitro the effect of the C-factor on interfacial debonding during curing of composite restorations using the acoustic emission (AE) technique. Finite element (FE) analyzes were also carried out to evaluate the interfacial stresses caused by shrinkage of the composite resin in restorations with different C-factors. Twenty extracted third molars were divided into 4 groups of 5. They were cut to form Class-I (Groups 1 and 2) and Class-II (Groups 3 and 4) cavities with different C-factors. The average C-factors of the four groups were 3.37, 2.88, 2.00, and 1.79, respectively. The cavities were then applied with an adhesive and restored with a composite, which was cured by a halogen light for 40 s. A 2-channel AE system was used to monitor the interfacial debonding, caused by shrinkage stress, between the tooth and restoration through an AE sensor attached to the surface of the specimen. Recording of the AE started at the same time as curing of the composite and lasted 10 min. Simplified FE models were used to evaluate the interfacial stresses in restorations with different C-factors, with a thermal load (temperature decrease) being applied to the composite resin to simulate its shrinkage. The mean and standard deviation of the total number of AE events for the four groups were 29.6±15.7, 10.0±5.8, 2.6±1.5, and 2.2±1.3, i.e. the number of AE events increased with an increase in the C-factor. The FE results also showed that, the higher the C-factor of the restoration, the higher the interfacial tensile stress between the tooth and restoration. From the results of the AE tests and FE simulations, it can be concluded that, the higher the C-factor, the higher the shrinkage stress and the more likely is interfacial debonding. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hsu, I-Chow, E-mail: ihsu@radonc.ucsf.ed; Bae, Kyounghwa; Shinohara, Katsuto
2010-11-01
Purpose: To estimate the rate of late Grade 3 or greater genitourinary (GU) and gastrointestinal (GI) adverse events (AEs) after treatment with external beam radiotherapy and prostate high-dose-rate (HDR) brachytherapy. Methods and Materials: Each participating institution submitted computed tomography-based HDR brachytherapy dosimetry data electronically for credentialing and for each study patient. Patients with locally confined Stage T1c-T3b prostate cancer were eligible for the present study. All patients were treated with 45 Gy in 25 fractions using external beam radiotherapy and one HDR implant delivering 19 Gy in two fractions. All AEs were graded according to the Common Terminology Criteria formore » Adverse Events, version 3.0. Late GU/GI AEs were defined as those occurring >9 months from the start of the protocol treatment, in patients with {>=}18 months of potential follow-up. Results: A total of 129 patients from 14 institutions were enrolled in the present study. Of the 129 patients, 125 were eligible, and AE data were available for 112 patients at analysis. The pretreatment characteristics of the patients were as follows: Stage T1c-T2c, 91%; Stage T3a-T3b, 9%; prostate-specific antigen level {<=}10 ng/mL, 70%; prostate-specific antigen level >10 but {<=}20 ng/mL, 30%; and Gleason score 2-6, 10%; Gleason score 7, 72%; and Gleason score 8-10, 18%. At a median follow-up of 29.6 months, three acute and four late Grade 3 GU/GI AEs were reported. The estimated rate of late Grade 3-5 GU and GI AEs at 18 months was 2.56%. Conclusion: This is the first prospective, multi-institutional trial of computed tomography-based HDR brachytherapy and external beam radiotherapy. The technique and doses used in the present study resulted in acceptable levels of AEs.« less
Ariza, F; Montilla-Coral, D; Franco, O; González, L F; Lozano, L C; Torres, A M; Jordán, J; Blanco, L F; Suárez, L; Cruz, G; Cepeda, M
2014-01-01
Multiple studies have analyzed perioperative factors related to adverse events (AEs) in children who require gastrointestinal endoscopic procedures (GEP) in settings where deep sedation is the preferred anesthetic technique over general anesthesia (GA) but not for the opposite case. We reviewed our anesthesia institutional database, seeking children less than 12 years who underwent GEP over a 5-year period. A logistic regression was used to determine significant associations between preoperative conditions, characteristics of the procedure, airway management, anesthetic approaches and the presence of serious and non-serious AEs. GA was preferred over deep sedation [77.8% vs. 22.2% in 2178 GEP under anesthesia care (n=1742)]. We found 96 AEs reported in 77 patients, including hypoxemia (1.82%), bronchospasm (1.14%) and laryngospasm (0.91%) as the most frequent. There were 2 cases of severe bradycardia related to laryngospasm/hypoxemia and a case of aspiration resulting in unplanned hospitalization, but there were no cases of intra- or postoperative deaths. Final predictive model for perioperative AEs included age <1 year, upper respiratory tract infections (URTI) <1 week prior to the procedure and low weight for the age (LWA) as independent risk factors and ventilation by facial mask as a protector against these events (p<0.05). AEs are infrequent and severe ones are remote in a setting where AG is preferred over deep sedation. Ventilatory AEs are the most frequent and depend on biometrical and comorbid conditions more than anesthetic drugs chosen. Age <1 year, history of URTI in the week prior to the procedure and LWA work as independent risk factors for AEs in these patients. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.
Lin, Zhichao; Guo, Zexiong; Qiu, Lin; Yang, Wanyoug; Lin, Mingxia
2016-12-01
Background To extend the time window for thrombolysis, reducing the time for diagnosis and detection of acute cerebral infarction seems to be warranted. Purpose To evaluate the feasibility of implementing an array spatial sensitivity technique (ASSET)-echo-planar imaging (EPI)-fluid attenuated inversion recovery (FLAIR) (AE-FLAIR) sequence into an acute cerebral infarction magnetic resonance (MR) evaluation protocol, and to assess the diagnostic value of AE-FLAIR combined with three-dimensional time-of-flight MR angiography (3D TOF MRA). Material and Methods A total of 100 patients (68 men, 32 women; age range, 44-82 years) with acute cerebral infarction, including 50 consecutive uncooperative and 50 cooperative patients, were evaluated with T1-weighted (T1W) imaging, T2-weighted (T2W) imaging, FLAIR, diffusion-weighted imaging (DWI), 3D TOF, EPI-FLAIR, and AE-FLAIR. Conventional FLAIR, EPI-FLAIR, and AE-FLAIR were assessed by two observers independently for image quality. The optimized group (AE-FLAIR and 3D TOF) and the control group (T1W imaging, T2W imaging, conventional FLAIR, DWI, and 3D TOF) were compared for evaluation time and diagnostic accuracy. Results One hundred and twenty-five lesions were detected and images having adequate diagnostic image quality were in 73% of conventional FLAIR, 62% of EPI-FLAIR, and 89% of AE-FLAIR. The detection time was 12 ± 1 min with 76% accuracy and 4 ± 0.5 min with 100% accuracy in the control and the optimized groups, respectively. Inter-observer agreements of κ = 0.78 and κ = 0.81 were for the optimized group and control group, respectively. Conclusion With reduced acquisition time and better image quality, AE-FLAIR combined with 3D TOF may be used as a rapid diagnosis tool in patients with acute cerebral infarction, especially in uncooperative patients.
NASA Astrophysics Data System (ADS)
Kubo, T.; Iwasato, T.; Higo, Y.; Kato, T.; Kaneshima, S.; Uehara, S.; Koizumi, S.; Imamura, M.; Tange, Y.
2015-12-01
Intermediate-depth earthquakes are seismic activities in Wadati-Benioff zone at depths from 60 km to 300 km, where subducting plates deform plastically rather than brittle failure. Although it has been reported that unstable faulting occurred during antigorite dehydration even at higher pressures than ~2 GPa (e.g., Jung et al., 2009), the recent study by Chernak and Hirth (2011) revealed that the syndefromational antigorite dehydration does not produces stick-slip instabilities but stable fault slip. In the present study, we newly developed an AE monitoring system for high-pressure reaction-deformation processes combined with D-DIA and synchrotron monochromatic X-ray to observe reaction kinetics, creep behaviors, and AE activities simultaneously. We applied this technique to investigate shear instability during syndeformational antigorite dehydration. High-pressure deformation experiments were conducted up to ~8 GPa, ~1050 K, and strain rates of 3.4-9.2 x 10-5 s-1 in compression using a D-DIA type apparatus installed at BL-04B1, SPring-8. 50 keV mono X-ray were used to measure reaction kinetics and stress-strain data. To monitor shear instabilities by detecting AEs, six piezoelectric devices were positioned between first and second stage anvils of MA 6-6 type system. We used three kinds of starting materials of polycrystalline antigorite, fine-grained forsterite polycrystal, and two-phase mixtures of antigorite and San Carlos olivine (10%, 30%, and 50%atg). Clear contrasts were observed in AE activities between forsterite and antigorite samples. AE activities detected within the forsterite polycrystal suggested (semi) brittle behaviors at low pressures during the cold compression stage. Almost no AEs were detected within the antigorite samples during any stages of cold compression, ramping, deformation, and syndeformational dehydration although localized deformation textures were observed in recovered samples. Instead, we detected some AEs outside the sample, indicating the stick slipping at the boundaries of cylindrical parts. Our results suggest that localized deformation and dehydration of antigorite do not enhance shear instability at high pressures at least in compression under drained condition.
Zaki, Ahmad; Chai, Hwa Kian; Aggelis, Dimitrios G.; Alver, Ninel
2015-01-01
Corrosion of reinforced concrete (RC) structures has been one of the major causes of structural failure. Early detection of the corrosion process could help limit the location and the extent of necessary repairs or replacement, as well as reduce the cost associated with rehabilitation work. Non-destructive testing (NDT) methods have been found to be useful for in-situ evaluation of steel corrosion in RC, where the effect of steel corrosion and the integrity of the concrete structure can be assessed effectively. A complementary study of NDT methods for the investigation of corrosion is presented here. In this paper, acoustic emission (AE) effectively detects the corrosion of concrete structures at an early stage. The capability of the AE technique to detect corrosion occurring in real-time makes it a strong candidate for serving as an efficient NDT method, giving it an advantage over other NDT methods. PMID:26251904
Zaki, Ahmad; Chai, Hwa Kian; Aggelis, Dimitrios G; Alver, Ninel
2015-08-05
Corrosion of reinforced concrete (RC) structures has been one of the major causes of structural failure. Early detection of the corrosion process could help limit the location and the extent of necessary repairs or replacement, as well as reduce the cost associated with rehabilitation work. Non-destructive testing (NDT) methods have been found to be useful for in-situ evaluation of steel corrosion in RC, where the effect of steel corrosion and the integrity of the concrete structure can be assessed effectively. A complementary study of NDT methods for the investigation of corrosion is presented here. In this paper, acoustic emission (AE) effectively detects the corrosion of concrete structures at an early stage. The capability of the AE technique to detect corrosion occurring in real-time makes it a strong candidate for serving as an efficient NDT method, giving it an advantage over other NDT methods.
NASA Astrophysics Data System (ADS)
Noorsuhada, M. N.; Abdul Hakeem, Z.; Soffian Noor, M. S.; Noor Syafeekha, M. S.; Azmi, I.
2017-12-01
Health monitoring of structures during their service life become a vital thing as it provides crucial information regarding the performance and condition of the structures. Acoustic emission (AE) is one of the non-destructive techniques (NDTs) that could be used to monitor the performance of the structures. Reinforced concrete (RC) beam associated with AE monitoring was monotonically loaded to failure under three-point loading. Correlation between average frequency and RA value (rise time / amplitude) was computed. The relationship was established to classify the crack types that propagated in the RC beam. The crack was classified as tensile crack and shear crack. It was found that the relationship is well matched with the actual crack pattern that appeared on the beam surface. Hence, this relationship is useful for prediction of the crack occurrence in the beam and its performance can be determined.
Arenas Jiménez, María Dolores; Ferre, Gabriel; Álvarez-Ude, Fernando
Haemodialysis (HD) patients are a high-risk population group. For these patients, an error could have catastrophic consequences. Therefore, systems that ensure the safety of these patients in an environment with high technology and great interaction of the human factor is a requirement. To show a systematic working approach, reproducible in any HD unit, which consists of recording the complications and errors that occurred during the HD session; defining which of those complications could be considered adverse event (AE), and therefore preventable; and carrying out a systematic analysis of them, as well as of underlying real or potential errors, evaluating their severity, frequency and detection; as well as establishing priorities for action (Failure Mode and Effects Analysis system [FMEA systems]). Retrospective analysis of the graphs of all HD sessions performed during one month (October 2015) on 97 patients, analysing all recorded complications. The consideration of these complications as AEs was based on a consensus among 13 health professionals and 2 patients. The severity, frequency and detection of each AE was evaluated by the FMEA system. We analysed 1303 HD treatments in 97 patients. A total of 383 complications (1 every 3.4 HD treatments) were recorded. Approximately 87.9% of them was deemed AEs and 23.7% complications related with patients' underlying pathology. There was one AE every 3.8 HD treatments. Hypertension and hypotension were the most frequent AEs (42.7 and 27.5% of all AEs recorded, respectively). Vascular-access related AEs were one every 68.5 HD treatments. A total of 21 errors (1 every 62 HD treatments), mainly related to the HD technique and to the administration of prescribed medication, were registered. The highest risk priority number, according to the FMEA, corresponded to errors related to patient body weight; dysfunction/rupture of the catheter; and needle extravasation. HD complications are frequent. Consideration of some of them as AEs could improve safety by facilitating the implementation of preventive measures. The application of the FMEA system allows stratifying real and potential errors in dialysis units and acting with the appropriate degree of urgency, developing and implementing the necessary preventive and improvement measures. Copyright © 2017 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.
A laboratory nanoseismological study on deep-focus earthquake micromechanics
Wang, Yanbin; Zhu, Lupei; Shi, Feng; ...
2017-07-21
Global earthquake occurring rate displays an exponential decay down to ~300 km and then peaks around 550 to 600 km before terminating abruptly near 700 km. How fractures initiate, nucleate, and propagate at these depths remains one of the greatest puzzles in earth science, as increasing pressure inhibits fracture propagation. We report nanoseismological analysis on high-resolution acoustic emission (AE) records obtained during ruptures triggered by partial transformation from olivine to spinel in Mg 2GeO 4, an analog to the dominant mineral (Mg,Fe) 2SiO 4 olivine in the upper mantle, using state-of-the-art seismological techniques, in the laboratory. AEs’ focal mechanisms, asmore » well as their distribution in both space and time during deformation, are carefully analyzed. Microstructure analysis shows that AEs are produced by the dynamic propagation of shear bands consisting of nanograined spinel. These nanoshear bands have a near constant thickness (~100 nm) but varying lengths and self-organize during deformation. This precursory seismic process leads to ultimate macroscopic failure of the samples. Several source parameters of AE events were extracted from the recorded waveforms, allowing close tracking of event initiation, clustering, and propagation throughout the deformation/transformation process. AEs follow the Gutenberg-Richter statistics with a well-defined b value of 1.5 over three orders of moment magnitudes, suggesting that laboratory failure processes are self-affine. The seismic relation between magnitude and rupture area correctly predicts AE magnitude at millimeter scales. A rupture propagation model based on strain localization theory is proposed. Future numerical analyses may help resolve scaling issues between laboratory AE events and deep-focus earthquakes.« less
A laboratory nanoseismological study on deep-focus earthquake micromechanics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Yanbin; Zhu, Lupei; Shi, Feng
Global earthquake occurring rate displays an exponential decay down to ~300 km and then peaks around 550 to 600 km before terminating abruptly near 700 km. How fractures initiate, nucleate, and propagate at these depths remains one of the greatest puzzles in earth science, as increasing pressure inhibits fracture propagation. We report nanoseismological analysis on high-resolution acoustic emission (AE) records obtained during ruptures triggered by partial transformation from olivine to spinel in Mg2GeO4, an analog to the dominant mineral (Mg,Fe)2SiO4 olivine in the upper mantle, using state-of-the-art seismological techniques, in the laboratory. AEs’ focal mechanisms, as well as their distributionmore » in both space and time during deformation, are carefully analyzed. Microstructure analysis shows that AEs are produced by the dynamic propagation of shear bands consisting of nanograined spinel. These nanoshear bands have a near constant thickness (~100 nm) but varying lengths and self-organize during deformation. This precursory seismic process leads to ultimate macroscopic failure of the samples. Several source parameters of AE events were extracted from the recorded waveforms, allowing close tracking of event initiation, clustering, and propagation throughout the deformation/transformation process. AEs follow the Gutenberg-Richter statistics with a well-defined b value of 1.5 over three orders of moment magnitudes, suggesting that laboratory failure processes are self-affine. The seismic relation between magnitude and rupture area correctly predicts AE magnitude at millimeter scales. A rupture propagation model based on strain localization theory is proposed. Future numerical analyses may help resolve scaling issues between laboratory AE events and deep-focus earthquakes.« less
A laboratory nanoseismological study on deep-focus earthquake micromechanics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Yanbin; Zhu, Lupei; Shi, Feng
Global earthquake occurring rate displays an exponential decay down to ~300 km and then peaks around 550 to 600 km before terminating abruptly near 700 km. How fractures initiate, nucleate, and propagate at these depths remains one of the greatest puzzles in earth science, as increasing pressure inhibits fracture propagation. We report nanoseismological analysis on high-resolution acoustic emission (AE) records obtained during ruptures triggered by partial transformation from olivine to spinel in Mg 2GeO 4, an analog to the dominant mineral (Mg,Fe) 2SiO 4 olivine in the upper mantle, using state-of-the-art seismological techniques, in the laboratory. AEs’ focal mechanisms, asmore » well as their distribution in both space and time during deformation, are carefully analyzed. Microstructure analysis shows that AEs are produced by the dynamic propagation of shear bands consisting of nanograined spinel. These nanoshear bands have a near constant thickness (~100 nm) but varying lengths and self-organize during deformation. This precursory seismic process leads to ultimate macroscopic failure of the samples. Several source parameters of AE events were extracted from the recorded waveforms, allowing close tracking of event initiation, clustering, and propagation throughout the deformation/transformation process. AEs follow the Gutenberg-Richter statistics with a well-defined b value of 1.5 over three orders of moment magnitudes, suggesting that laboratory failure processes are self-affine. The seismic relation between magnitude and rupture area correctly predicts AE magnitude at millimeter scales. A rupture propagation model based on strain localization theory is proposed. Future numerical analyses may help resolve scaling issues between laboratory AE events and deep-focus earthquakes.« less
Suzuki, Takashi; Osei, Joseph H; Sasaki, Akihiro; Adimazoya, Michelle; Appawu, Maxwell; Boakye, Daniel; Ohta, Nobuo; Dadzie, Samuel
2016-09-01
Dengue is one of the emerging diseases that can mostly only be controlled by vector control since there is no vaccine for the disease. Although, Dengue has not been reported in Ghana, movement of people from neighbouring countries where the disease has been reported can facilitate transmission of the disease. This study was carried on the University of Ghana campus to determine the risk of transmission of viral haemorrhagic fevers and the insecticide susceptibility status of Ae. aegypti in some sites in Accra, Ghana. Larval surveys were carried to inspect containers within households and estimate larval indices and adult Aedes mosquitoes were collected using human landing collection technique. WHO tube assays was used to assess the insecticide susceptibility status of Aedes mosquitoes. Ae. aegypti were the most prevalent species, 75.5% and followed by Ae. vittatus , 23.9 %. Ae. albopictus and Ae. granti were in smaller numbers. Household index (HI), Breteau index (BI), and container index were calculated as 8.2%, 11.2% and 10.3% respectively with man-vector contact rate of 0.67 bites/man-hour estimated for the area. The mortalities recorded for Ae. aegypti from WHO tube assays was 88%, 94%, 80% and 99% for DDT (4%), deltamethrin (0.05%), lambdacyhalothrin (0.05%) and permethrin (0.75%) respectively. The survey results indicated that the density of Aedes mosquitoes was considered to be sufficient to promote an outbreak of viral haemorrhagic fevers on Legon Campus. Aedes mosquitoes were found to be resistant to DDT, deltamethrin and lamdacyhalothrin, but susceptible to permethrin. This study was supported in part by Japan Initiative for Global Research Network on Infectious Diseases (J-Grid).
Uemura, Shinya; Iwashita, Takuji; Iwata, Keisuke; Mukai, Tsuyoshi; Osada, Shinji; Sekino, Takafumi; Adachi, Takahito; Kawai, Masahiko; Yasuda, Ichiro; Shimizu, Masahito
2018-05-03
Malignant gastric outlet obstruction (GOO) often develops in patients with advanced pancreatic cancer (APC). It is not clear whether endoscopic duodenal stenting (DS) or surgical gastrojejunostomy (GJJ) is preferable as palliative treatment. To compare the efficacy and safety of GJJ and DS for GOO with APC. Consecutive 99 patients who underwent DS or GJJ for GOO with APC were evaluated. We compared the technical and clinical success rates, the incidence of adverse event (AE), the time to start chemotherapy and discharge and survival durations between DS and GJJ. Prognostic factors for overall survival (OS) were investigated on the multivariate analysis. GOO was managed with GJJ in 35 and DS in 64. The technical and clinical success rates were comparable. DS was associated with shorter time to start oral intake and earlier chemotherapy start and discharge. No difference was seen in the early and late AE rates. Multivariate analyses of prognostic factors for OS showed that performance status ≧2, administration of chemotherapy, and presence of obstructive jaundice to be significant factors. There were no significant differences in survival durations between the groups, regardless of the PS. There were no significant differences in the technical and clinical success and AE rates and survival duration between DS and GJJ in management of GOO by APC. DS may be a preferable option over GJJ given that it will lead to an earlier return to oral intake, a shortened length of hospital stay, and finally an earlier referral for chemotherapy. Copyright © 2018 IAP and EPC. Published by Elsevier B.V. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Two sampling techniques, agar extraction (AE) and centrifuge sugar flotation extraction (CSFE) were compared to determine their relative efficacy to recover immature stages of Culicoides spp from salt marsh substrates. Three types of samples (seeded with known numbers of larvae, homogenized field s...
Adequacy of surface analytical tools for studying the tribology of ceramics
NASA Technical Reports Server (NTRS)
Sliney, H. E.
1986-01-01
Surface analytical tools are very beneficial in tribological studies of ceramics. Traditional methods of optical microscopy, XRD, XRF, and SEM should be combined with newer surface sensitive techniques especially AES and XPS. ISS and SIMS can also be useful in providing additional compositon details. Tunneling microscopy and electron energy loss spectroscopy are less known techniques that may also prove useful.
Dick, Randall; Ferrara, Michael S; Agel, Julie; Courson, Ron; Marshall, Stephen W; Hanley, Michael J; Reifsteck, Fred
2007-01-01
Objective: To review 16 years of National Collegiate Athletic Association (NCAA) injury surveillance data for men's football and identify potential areas for injury prevention initiatives. Background: Football is a high-velocity collision sport in which injuries are expected. Football tends to have one of the highest injury rates in sports. Epidemiologic data helps certified athletic trainers and other clinicians identify injury trends and patterns to appropriately design and institute injury prevention protocols and then measure their effects. Main Results: During the 16-year reporting period, about 19% of the Division I, II, and III NCAA institutions sponsoring football participated in the Injury Surveillance System. The results from the 16-year study period show little variation in the injury rates over time: games averaged 36 injuries per 1000 athlete-exposures (A-Es); fall practice, approximately 4 injuries per 1000 A-Es; and spring practice, about 10 injuries per 1000 A-Es. The game injury rate was more than 9 times higher than the in-season practice injury rate (35.90 versus 3.80 injuries per 1000 A-Es, rate ratio = 9.1, 95% confidence interval = 9.0, 9.2), and the spring practice injury rate was more than 2 times higher than the fall practice injury rate (9.62 versus 3.80 injuries per 1000 A-Es, rate ratio = 2.5, 95% confidence interval = 2.5, 2.6). The rate ratio for games versus fall practices was greatest for upper leg contusions (18.1 per 1000 A-Es), acromioclavicular joint sprains (14.0 per 1000 A-Es), knee internal derangements (13.4 per 1000 A-Es), ankle ligament sprains (12.0 per 1000 A-Es), and concussions (11.1 per 1000 A-Es). Recommendations: Football is a complex sport that requires a range of skills performed by athletes with a wide variety of body shapes and types. Injury risks are greatest during games. Thus, injury prevention measures should focus on position-specific activities to reduce the injury rate. As equipment technology improves for the helmet, shoulder pads, and other protective devices, appropriate injury surveillance procedures should be performed to determine the effect of the new equipment on injury rates. A consistent evaluation of injury trends and patterns will assist decision makers in designing injury prevention techniques in areas that warrant the greatest attention and suggesting rule changes and modifications based on the data. PMID:17710170
NASA Astrophysics Data System (ADS)
Lompar, Miloš; Ćurić, Mladjen; Romanic, Djordje
2017-09-01
Despite an important role the aerosols play in all stages of cloud lifecycle, their representation in numerical weather prediction models is often rather crude. This paper investigates the effects the explicit versus implicit inclusion of aerosols in a microphysics parameterization scheme in Weather Research and Forecasting (WRF) - Advanced Research WRF (WRF-ARW) model has on cloud dynamics and microphysics. The testbed selected for this study is a severe mesoscale convective system with supercells that struck west and central parts of Serbia in the afternoon of July 21, 2014. Numerical products of two model runs, i.e. one with aerosols explicitly (WRF-AE) included and another with aerosols implicitly (WRF-AI) assumed, are compared against precipitation measurements from surface network of rain gauges, as well as against radar and satellite observations. The WRF-AE model accurately captured the transportation of dust from the north Africa over the Mediterranean and to the Balkan region. On smaller scales, both models displaced the locations of clouds situated above west and central Serbia towards southeast and under-predicted the maximum values of composite radar reflectivity. Similar to satellite images, WRF-AE shows the mesoscale convective system as a merged cluster of cumulonimbus clouds. Both models over-predicted the precipitation amounts; WRF-AE over-predictions are particularly pronounced in the zones of light rain, while WRF-AI gave larger outliers. Unlike WRF-AI, the WRF-AE approach enables the modelling of time evolution and influx of aerosols into the cloud which could be of practical importance in weather forecasting and weather modification. Several likely causes for discrepancies between models and observations are discussed and prospects for further research in this field are outlined.
Advanced energy system program
NASA Astrophysics Data System (ADS)
Trester, K.
1989-02-01
The objectives of the program are to design, develop and demonstrate a natural-gas-fueled, highly recuperated, 50 kW Brayton-cycle cogeneration system for commercial, institutional, and multifamily residential applications. Marketing studies have shown that this Advanced Energy System (AES), with its many unique and cost-effective features, has the potential to offer significant reductions in annual electrical and thermal energy costs to the consumer. Specific advantages of the system that result in low cost of ownership are high electrical efficiency (30 percent, HHV), low maintenance, high reliability and long life (20 years).
VIRTEX-5 Fpga Implementation of Advanced Encryption Standard Algorithm
NASA Astrophysics Data System (ADS)
Rais, Muhammad H.; Qasim, Syed M.
2010-06-01
In this paper, we present an implementation of Advanced Encryption Standard (AES) cryptographic algorithm using state-of-the-art Virtex-5 Field Programmable Gate Array (FPGA). The design is coded in Very High Speed Integrated Circuit Hardware Description Language (VHDL). Timing simulation is performed to verify the functionality of the designed circuit. Performance evaluation is also done in terms of throughput and area. The design implemented on Virtex-5 (XC5VLX50FFG676-3) FPGA achieves a maximum throughput of 4.34 Gbps utilizing a total of 399 slices.
Entropy based file type identification and partitioning
2017-06-01
energy spectrum,” Proceedings of the Twenty-Ninth International Florida Artificial Intelligence Research Society Conference, pp. 288–293, 2016...ABBREVIATIONS AES Advanced Encryption Standard ANN Artificial Neural Network ASCII American Standard Code for Information Interchange CWT...the identification of file types and file partitioning. This approach has applications in cybersecurity as it allows for a quick determination of
Energy Systems Integration News | Energy Systems Integration Facility |
us at the ESIF. NREL Releases High-Pen PV Handbook for Distribution Engineers As solar photovoltaic PV for Ancillary Services NREL, AES, the Puerto Rico Electric Power Authority, First Solar, and the technologies, such as solar, demand response, and smart consumer appliances Advances in grid design and
World apheresis registry report.
Stegmayr, Bernd; Ptak, Jan; Wikström, Björn
2007-02-01
The establishment of national apheresis registries has been helpful to learn about therapeutic profiles and adverse event incidences. During 2003, the World Apheresis Registry was established and centers from all countries were invited to participate to register their apheresis activities (at www.iml.umu.se/medicin). In this paper, we will report and analyze the first data retrieved from three centers, in 2 European countries, that registered a total of 388 therapeutic apheresis treatments in 122 patients, 95% due to acute indications. Statistical analyses were performed using an independent Student t-test and Fisher's test. A p-value of less than 0.05 was considered significant. Fifty percent of the treated patients were women. The mean age of the patients was 51 years (+/-17, range 16-84) and there was no difference between genders (w 50.4, m 51.6 years). Diagnoses for treatment were mainly neurological and vasculitis. In 63% peripheral access was used with a central double lumen catheter, 22% in the jugular vein, 8% in the subclavian vein and 6% the femoral vein. Significant inter-center differences were seen in regard to the access used. The main technique used was centrifugation for conventional plasma exchange (86%), while other modes were leukapheresis, erythrapheresis, platelet apheresis, LDL-apheresis and adsorption of antibodies. Citrate was the only anticoagulant in 92%. During plasma exchange procedures using centrifugation, replacement was by albumin only (58%) or plasma, the latter often in combination with albumin (42%). Adverse events (AEs) were noted in 11% of the procedures. Patients with hypocalcaemia side effects with tingling sensations were included in those data as mild AE and as moderate AEs if they received calcium (Ca) medication. No patient died due to adverse effects. A mild AE was present in 1.8% and moderate in 8.5%. During two procedures (0.5%), the AE was considered severe and therefore the procedure was interrupted. If those with AEs due to lower calcium were removed from analyses, 6.4% had AEs. Significantly more AEs were found when plasma was used as a replacement fluid (p=0.017, RR 2.05, CI 1.17-3.60). There were no differences in the incidence of AEs between genders. The number of procedures was too small to allow sub analyses of AEs in relation to the diagnoses. Adverse events were not related to the procedure used (p=0.095). Those who received additional Ca infusion during the procedure had no AEs (40 sessions) while the others who received no prophylactic Ca had an AE on 45 occasions (p=0.0141, RR 1.116, CI 1.08-1.15). Data from the registry shows that centers have various approaches to apheresis. One can learn from each other's experience to reduce side effects and improve efficacy. From these data we noted that prophylactic Ca infusion reduced side effects.
Locating the origin of stick slip instabilities in sheared granular layers
NASA Astrophysics Data System (ADS)
Korkolis, Evangelos; Niemeijer, André
2017-04-01
Acoustic emission (AE) monitoring is a non-invasive technique widely used to evaluate the state of materials and structures. We have developed a system that can locate the source of AE events associated with unstable sliding (stick-slip) of sheared granular layers during laboratory friction experiments. Our aim is to map the spatial distribution of energy release due to permanent microstructural changes, using AE source locations as proxies. This will allow us to determine the distribution of applied work in a granular medium, which will be useful in developing constitutive laws that describe the frictional behavior of such materials. The AE monitoring system is installed on a rotary shear apparatus. This type of apparatus is used to investigate the micromechanical processes responsible for the macroscopic frictional behavior of granular materials at large shear displacements. Two arrays of 8 piezoelectric sensors each are installed into the ring-shaped steel pistons that confine our samples. The sensors are connected to a high-speed, multichannel oscilloscope that can record full waveforms. The apparatus is also equipped with a system that continuously records normal and lateral (shear) loads and displacements, as well as pore fluid pressure. Thus, we can calculate the frictional and volumetric response of our granular aggregates, as well as the location of AE sources. Here, we report on the results of room temperature experiments on granular aggregates consisting of glass beads or segregated mixtures of glass beads and calcite, at up to 5 MPa normal stress and sliding velocities between 1 and 100 μm/s. Under these conditions, glass beads exhibit unstable sliding behavior accompanied by significant AE activity, whereas calcite exhibits stable sliding and produces no AEs. We recorded a range of unstable sliding behaviors, from fast, regular stick slip at high normal stress (> 4 MPa) and sliding velocities below 20 μm/s, to irregular stick slip at low normal stress or sliding velocities above 20 μm/s. We calculated the source location of each AE associated with significant stress drops (slip events). A very prominent feature, particularly among the large shear displacement experiments, was the development of regions that sustained increased AE activity. Some of these regions remained fixed in space, whereas others kept migrating with increasing shear displacement. We observed that for an arbitrarily small number of consecutive slip events, their associated AEs did not necessarily nucleate in the same region. We believe that the calculated AE source locations reveal the sites where load-bearing microstructures, known as force chains, begin to fail, leading to slip instabilities. The existence of regions of increased AE activity suggests that triggering of force chain failure is controlled to some extent by the loading conditions imposed on the sample by the machine, but may also indicate the lasting influence of previous particle re-organization events on the particles populating these regions.
NASA Astrophysics Data System (ADS)
Verstrynge, E.; Wevers, M.; Ghiassi, B.; Lourenço, P. B.
2016-01-01
Different types of strengthening systems, based on fiber reinforced materials, are under investigation for external strengthening of historic masonry structures. A full characterization of the bond behavior and of the short- and long-term failure mechanisms is crucial to ensure effective design, compatibility with the historic substrate and durability of the strengthening solution. Therein, non-destructive techniques are essential for bond characterization, durability assessment and on-site condition monitoring. In this paper, the acoustic emission (AE) technique is evaluated for debonding characterization and localization on fiber reinforced polymer (FRP) and steel reinforced grout-strengthened clay bricks. Both types of strengthening systems are subjected to accelerated ageing tests under thermal cycles and to single-lap shear bond tests. During the reported experimental campaign, AE data from the accelerated ageing tests demonstrated the thermal incompatibility between brick and epoxy-bonded FRP composites, and debonding damage was successfully detected, characterized and located. In addition, a qualitative comparison is made with digital image correlation and infrared thermography, in view of efficient on-site debonding detection.
Concurrent Ultrasonic Tomography and Acoustic Emission in Solid Materials
NASA Astrophysics Data System (ADS)
Chow, Thomas M.
A series of experiments were performed to detect stress induced changes in the elastic properties of various solid materials. A technique was developed where these changes were monitored concurrently by two methods, ultrasonic tomography and acoustic emission monitoring. This thesis discusses some experiments in which acoustic emission (AE) and ultrasonic tomography were performed on various samples of solid materials including rocks, concrete, metals, and fibre reinforced composites. Three separate techniques were used to induce stress in these samples. Disk shaped samples were subject to stress via diametral loading using an indirect tensile test geometry. Cylindrical samples of rocks and concrete were subject to hydraulic fracture tests, and rectangular samples of fibre reinforced composite were subject to direct tensile loading. The majority of the samples were elastically anisotropic. Full waveform acoustic emission and tomographic data were collected while these samples were under load to give information concerning changes in the structure of the material as it was undergoing stress change and/or failure. Analysis of this data indicates that AE and tomographic techniques mutually compliment each other to give a view of the stress induced elastic changes in the tested samples.
NASA Astrophysics Data System (ADS)
Lü, Hua-Ping; Wang, Shi-Hong; Li, Xiao-Wen; Tang, Guo-Ning; Kuang, Jin-Yu; Ye, Wei-Ping; Hu, Gang
2004-06-01
Two-dimensional one-way coupled map lattices are used for cryptography where multiple space units produce chaotic outputs in parallel. One of the outputs plays the role of driving for synchronization of the decryption system while the others perform the function of information encoding. With this separation of functions the receiver can establish a self-checking and self-correction mechanism, and enjoys the advantages of both synchronous and self-synchronizing schemes. A comparison between the present system with the system of advanced encryption standard (AES) is presented in the aspect of channel noise influence. Numerical investigations show that our system is much stronger than AES against channel noise perturbations, and thus can be better used for secure communications with large channel noise.
2012-08-03
CAPE CANAVERAL, Fla. – Inside the Space Life Sciences Laboratory, or SLSL, at NASA’s Kennedy Space Center in Florida, red leaf lettuce plants were harvested from a plant growth chamber. The plants were grown under red and blue LED lights. The plant experiment at Kennedy is part of the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. This plant experiment studies the effects of different types of lighting on plants such as radishes and leaf lettuce. Results of these studies will help provide information on how to grow food sources for deep space exploration missions. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. Photo credit: NASA/Frank Ochoa-Gonzales
Lin, Shi-Ming; Lu, Sheng-Nan; Chen, Ping-Tsung; Jeng, Long-Bin; Chen, Shinn-Cherng; Hu, Chi-Tan; Yang, Sien-Sing; Le Berre, Marie-Aude; Liu, Xuan; Mitchell, David Y; Prins, Klaas; Grevel, Joachim; Peña, Carol A E; Meinhardt, Gerold
2017-03-01
Sorafenib significantly improves survival in patients with advanced hepatocellular carcinoma (HCC). This phase IV study assessed sorafenib efficacy/safety in Taiwanese patients with advanced HCC and Child-Pugh A status. All patients received 400 mg sorafenib BID. Safety, efficacy, sorafenib pharmacokinetics, and Child-Pugh progression were evaluated. A hand-foot skin reaction (HFSR) prevention substudy assessed HFSR incidence and grade/severity and time to HFSR in 29 and 34 patients randomized to corticosteroid and noncorticosteroid ointments, respectively, and in 88 nonrandomized patients. The 151 patients included 120 (80%) male patients and 81 (54%) with stage IV disease. Mean sorafenib dose was 626 mg/day, and median treatment duration was 4.2 months. Median overall survival (OS), progression-free survival, and time to progression (TTP) were 8.6, 2.7, and 3.8 months, respectively. Disease control and response rates (partial responses only) were 48 and 6.6%, respectively. Median TTP from Child-Pugh A to B/C was 88 days. Drug-related adverse events (AEs) occurred in 89.4% of patients; none were new or unexpected. The most frequent grade ≥3 drug-related, treatment-emergent AEs were HFSR (13.2%), diarrhea (11.9%), and hypertension (6.6%). Corticosteroid ointment tended to reduce the severity and incidence of all HFSR-associated parameters. Pharmacokinetic exposure was unaltered by Child-Pugh progression. The final pharmacokinetic model predicted 13.1 and 33.8% reductions in sorafenib exposure over 6 and 12 months, respectively. There was a trend of longer OS and TTP in Taiwanese patients with advanced HCC compared with patients with advanced HCC in the Asia-Pacific trial. Sorafenib exposure did not correlate with liver function. Reduced pharmacokinetic exposure over time was unrelated to reduced or interrupted dosing.
Confidential storage and transmission of medical image data.
Norcen, R; Podesser, M; Pommer, A; Schmidt, H-P; Uhl, A
2003-05-01
We discuss computationally efficient techniques for confidential storage and transmission of medical image data. Two types of partial encryption techniques based on AES are proposed. The first encrypts a subset of bitplanes of plain image data whereas the second encrypts parts of the JPEG2000 bitstream. We find that encrypting between 20% and 50% of the visual data is sufficient to provide high confidentiality.
Leenders, A M; Schotanus, M G M; Wind, R J P; Borghans, R A P; Kort, N P
2018-04-30
Patient-specific instrumentation (PSI) for unicompartmental knee arthroplasty (UKA) has been available for a few years. However, limited literature is available on this subject. Hence, the aim of this cohort study is to evaluate the 2 years' results of our first experiences with the use of PSI in UKA. It is hypothesised that there is no advantage in rate of adverse events and in radiological and functional outcomes in comparison to literature on the conventional method. This cohort included 129 knees of 122 patients, operated by one surgeon. Outcome measures were the rate of adverse events (AEs); implant position as determined on radiographs; the accuracy of the default and approved planning of the implant sizes and the patient-reported outcome measures (PROMs) preoperatively, and at 3, 12 and 24 months, postoperatively. A total of 6 (4.9%) AEs were observed in this study, with 4 (3.3%) tibial fractures being the main complication. The mean postoperative biomechanical axis was 176.4° and in the majority of cases, the radiographic criteria, as determined by the manufacturer, were met. The tibial component showed 20 (16.4%) outliers in the sagittal and 3 (2.5%) outliers in the frontal plane. There were no outliers of the femoral component. For the femoral and tibial components, respectively, in 125 (96.9%) and 79 (61.7%) cases, there was an agreement between approved planning and implanted component size. All PROMs improved significantly after surgery. Tibial fracture was the most common AE, probably related to the transition from cemented to uncemented UKA. Perioperative modifications to the surgical technique were made in order to prevent this AE. Improvements should be made to the operation technique of the uncemented tibial plateau to obtain an adequate placement and at the same time reduce the risk for tibial fracture. The PSI technique was a reliable tool for the placement of the femoral component. Functional outcome was in line with literature on the conventional method. It is strongly recommended that the surgeon approves every preoperative plan, in order to optimise the accuracy during the PSI surgery. III.
Assessment of ground-based monitoring techniques applied to landslide investigations
NASA Astrophysics Data System (ADS)
Uhlemann, S.; Smith, A.; Chambers, J.; Dixon, N.; Dijkstra, T.; Haslam, E.; Meldrum, P.; Merritt, A.; Gunn, D.; Mackay, J.
2016-01-01
A landslide complex in the Whitby Mudstone Formation at Hollin Hill, North Yorkshire, UK is periodically re-activated in response to rainfall-induced pore-water pressure fluctuations. This paper compares long-term measurements (i.e., 2009-2014) obtained from a combination of monitoring techniques that have been employed together for the first time on an active landslide. The results highlight the relative performance of the different techniques, and can provide guidance for researchers and practitioners for selecting and installing appropriate monitoring techniques to assess unstable slopes. Particular attention is given to the spatial and temporal resolutions offered by the different approaches that include: Real Time Kinematic-GPS (RTK-GPS) monitoring of a ground surface marker array, conventional inclinometers, Shape Acceleration Arrays (SAA), tilt meters, active waveguides with Acoustic Emission (AE) monitoring, and piezometers. High spatial resolution information has allowed locating areas of stability and instability across a large slope. This has enabled identification of areas where further monitoring efforts should be focused. High temporal resolution information allowed the capture of 'S'-shaped slope displacement-time behaviour (i.e. phases of slope acceleration, deceleration and stability) in response to elevations in pore-water pressures. This study shows that a well-balanced suite of monitoring techniques that provides high temporal and spatial resolutions on both measurement and slope scale is necessary to fully understand failure and movement mechanisms of slopes. In the case of the Hollin Hill landslide it enabled detailed interpretation of the geomorphological processes governing landslide activity. It highlights the benefit of regularly surveying a network of GPS markers to determine areas for installation of movement monitoring techniques that offer higher resolution both temporally and spatially. The small sensitivity of tilt meter measurements to translational movements limited the ability to record characteristic 'S'-shaped landslide movements at Hollin Hill, which were identified using SAA and AE measurements. This high sensitivity to landslide movements indicates the applicability of SAA and AE monitoring to be used in early warning systems, through detecting and quantifying accelerations of slope movement.
Quantitative acoustic emission monitoring of fatigue cracks in fracture critical steel bridges.
DOT National Transportation Integrated Search
2014-01-01
The objective of this research is to evaluate the feasibility to employ quantitative acoustic : emission (AE) techniques for monitoring of fatigue crack initiation and propagation in steel : bridge members. Three A36 compact tension steel specimens w...
Tang, Jialin; Soua, Slim; Mares, Cristinel; Gan, Tat-Hean
2017-01-01
The identification of particular types of damage in wind turbine blades using acoustic emission (AE) techniques is a significant emerging field. In this work, a 45.7-m turbine blade was subjected to flap-wise fatigue loading for 21 days, during which AE was measured by internally mounted piezoelectric sensors. This paper focuses on using unsupervised pattern recognition methods to characterize different AE activities corresponding to different fracture mechanisms. A sequential feature selection method based on a k-means clustering algorithm is used to achieve a fine classification accuracy. The visualization of clusters in peak frequency−frequency centroid features is used to correlate the clustering results with failure modes. The positions of these clusters in time domain features, average frequency−MARSE, and average frequency−peak amplitude are also presented in this paper (where MARSE represents the Measured Area under Rectified Signal Envelope). The results show that these parameters are representative for the classification of the failure modes. PMID:29104245
Experimental verification of the shape of the excitation depth distribution function for AES
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tougaard, S.; Jablonski, A.; Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw
2011-09-15
In the common formalism of AES, it is assumed that the in-depth distribution of ionizations is uniform. There are experimental indications that this assumption may not be true for certain primary electron energies and solids. The term ''excitation depth distribution function'' (EXDDF) has been introduced to describe the distribution of ionizations at energies used in AES. This function is conceptually equivalent to the Phi-rho-z function of electron microprobe analysis (EPMA). There are, however, experimental difficulties to determine this function in particular for energies below {approx} 10 keV. In the present paper, we investigate the possibility of determining the shape ofmore » the EXDDF from the background of inelastically scattered electrons on the low energy side of the Auger electron features in the electron energy spectra. The experimentally determined EXDDFs are compared with the EXDDFs determined from Monte Carlo simulations of electron trajectories in solids. It is found that this technique is useful for the experimental determination of the EXDDF function.« less
NASA Astrophysics Data System (ADS)
Bai, F.; Gagar, D.; Foote, P.; Zhao, Y.
2017-02-01
Acoustic Emission (AE) monitoring can be used to detect the presence of damage as well as determine its location in Structural Health Monitoring (SHM) applications. Information on the time difference of the signal generated by the damage event arriving at different sensors in an array is essential in performing localisation. Currently, this is determined using a fixed threshold which is particularly prone to errors when not set to optimal values. This paper presents three new methods for determining the onset of AE signals without the need for a predetermined threshold. The performance of the techniques is evaluated using AE signals generated during fatigue crack growth and compared to the established Akaike Information Criterion (AIC) and fixed threshold methods. It was found that the 1D location accuracy of the new methods was within the range of < 1 - 7.1 % of the monitored region compared to 2.7% for the AIC method and a range of 1.8-9.4% for the conventional Fixed Threshold method at different threshold levels.
Fracture of Human Femur Tissue Monitored by Acoustic Emission Sensors
Aggelis, Dimitrios. G.; Strantza, Maria; Louis, Olivia; Boulpaep, Frans; Polyzos, Demosthenes; van Hemelrijck, Danny
2015-01-01
The study describes the acoustic emission (AE) activity during human femur tissue fracture. The specimens were fractured in a bending-torsion loading pattern with concurrent monitoring by two AE sensors. The number of recorded signals correlates well with the applied load providing the onset of micro-fracture at approximately one sixth of the maximum load. Furthermore, waveform frequency content and rise time are related to the different modes of fracture (bending of femur neck or torsion of diaphysis). The importance of the study lies mainly in two disciplines. One is that, although femurs are typically subjects of surgical repair in humans, detailed monitoring of the fracture with AE will enrich the understanding of the process in ways that cannot be achieved using only the mechanical data. Additionally, from the point of view of monitoring techniques, applying sensors used for engineering materials and interpreting the obtained data pose additional difficulties due to the uniqueness of the bone structure. PMID:25763648
Tang, Jialin; Soua, Slim; Mares, Cristinel; Gan, Tat-Hean
2017-11-01
The identification of particular types of damage in wind turbine blades using acoustic emission (AE) techniques is a significant emerging field. In this work, a 45.7-m turbine blade was subjected to flap-wise fatigue loading for 21 days, during which AE was measured by internally mounted piezoelectric sensors. This paper focuses on using unsupervised pattern recognition methods to characterize different AE activities corresponding to different fracture mechanisms. A sequential feature selection method based on a k-means clustering algorithm is used to achieve a fine classification accuracy. The visualization of clusters in peak frequency-frequency centroid features is used to correlate the clustering results with failure modes. The positions of these clusters in time domain features, average frequency-MARSE, and average frequency-peak amplitude are also presented in this paper (where MARSE represents the Measured Area under Rectified Signal Envelope). The results show that these parameters are representative for the classification of the failure modes.
NASA Astrophysics Data System (ADS)
Doering, Ryan Lee
Herbig Ae/Be stars are considered the intermediate-mass analogs of the low-mass pre-main sequence T Tauri stars. Observations reveal that they are surrounded by dusty matter that may provide the solid-state material for building planets. Determining the dust parameters provides constraints for planet formation theory, and yields information about the matter around intermediate-mass stars as they approach the main sequence. In this dissertation, I present the results of a multiwavelength imaging and radiative transfer modeling study of Herbig Ae/Be stars, and a near-infrared instrumentation project, with the aim of parameterizing the dust in these systems. The Hubble Space Telescope was used to search for optical light scattered by dust in a sample of young stars. This survey provided the first scattered-light image of the circumstellar environment around the Herbig Ae/Be star HD 97048. Structure is observed in the dust distribution similar to that seen in other Herbig Ae/Be systems. A ground-based near-infrared imaging study of Herbig Ae/ Be candidates was also carried out. Photometry was collected for spectral energy distribution construction, and binary candidates were resolved. A mid- infrared image of the low-mass debris system, AU Microscopii, is presented, being relevant to the study of Herbig Ae/Be stars. Detailed dust modeling of HD 97048 and HD 100546 was carried out with a two- component geometry consisting of a flared disk and an extended envelope. The models achieve a reasonable global fit to the spectral energy distributions, and produce images with the desired geometry. The disk midplane densities are found to go as r -0.5 and r -1.8 , giving disk dust masses of 3.0 × 10^-4 and 5.9 × 10 ^5 [Special characters omitted.] for HD 97048 and HD 100546, respectively. A gas-to-dust mass ratio lower limit of 3.2 was calculated for HD 97048. In order to advance the imaging capabilities available for observations of Herbig Ae/Be stars, I have participated in the development of the WIYN High Resolution Infrared Camera. The instrument operates in the near-infrared (~0.8 - 2.5 mm), includes 13 filters, and has a pixel size of ~0.1 inches, resulting in a field of view of ~3' × 3'. An angular resolution of ~0.25 inches is anticipated. I provide an overview of the instrument, and report performance results with an emphasis on detector characterization.
A formula for evaluating colour differences for thread sewn into fabric samples
NASA Astrophysics Data System (ADS)
Steder, Thorsten
In-service rails can develop several types of structural defects due to fatigue and wear caused by rolling stock passing over them. Most rail defects will develop gradually over time thus permitting inspection engineers to detect them in time before final failure occurs. In the UK, certain types of severe rail defects such as tache ovales, require the fitting of emergency clamps and the imposing of an Emergency Speed Restriction (ESR) until the defects are removed. Acoustic emission (AE) techniques can be applied for the detection and continuous monitoring of defect growth therefore removing the need of imposing strict ESRs. The work reported herewith aims to develop a sound methodology for the application of AE in order to detect and subsequently monitor damage evolution in rails. To validate the potential of the AE technique, tests have been carried out under laboratory conditions on three and four-point bending samples manufactured from 260 grade rail steel. Further tests, simulating the background noise conditions caused by passing rolling stock have been carried out using special experimental setups. The crack growth events have been simulated using a pencil tip break..
Estimation of Fine and Oversize Particle Ratio in a Heterogeneous Compound with Acoustic Emissions.
Nsugbe, Ejay; Ruiz-Carcel, Cristobal; Starr, Andrew; Jennions, Ian
2018-03-13
The final phase of powder production typically involves a mixing process where all of the particles are combined and agglomerated with a binder to form a single compound. The traditional means of inspecting the physical properties of the final product involves an inspection of the particle sizes using an offline sieving and weighing process. The main downside of this technique, in addition to being an offline-only measurement procedure, is its inability to characterise large agglomerates of powders due to sieve blockage. This work assesses the feasibility of a real-time monitoring approach using a benchtop test rig and a prototype acoustic-based measurement approach to provide information that can be correlated to product quality and provide the opportunity for future process optimisation. Acoustic emission (AE) was chosen as the sensing method due to its low cost, simple setup process, and ease of implementation. The performance of the proposed method was assessed in a series of experiments where the offline quality check results were compared to the AE-based real-time estimations using data acquired from a benchtop powder free flow rig. A designed time domain based signal processing method was used to extract particle size information from the acquired AE signal and the results show that this technique is capable of estimating the required ratio in the washing powder compound with an average absolute error of 6%.
Advanced Ceramics for Use as Fuel Element Materials in Nuclear Thermal Propulsion Systems
NASA Technical Reports Server (NTRS)
Valentine, Peter G.; Allen, Lee R.; Shapiro, Alan P.
2012-01-01
With the recent start (October 2011) of the joint National Aeronautics and Space Administration (NASA) and Department of Energy (DOE) Advanced Exploration Systems (AES) Nuclear Cryogenic Propulsion Stage (NCPS) Program, there is renewed interest in developing advanced ceramics for use as fuel element materials in nuclear thermal propulsion (NTP) systems. Three classes of fuel element materials are being considered under the NCPS Program: (a) graphite composites - consisting of coated graphite elements containing uranium carbide (or mixed carbide), (b) cermets (ceramic/metallic composites) - consisting of refractory metal elements containing uranium oxide, and (c) advanced carbides consisting of ceramic elements fabricated from uranium carbide and one or more refractory metal carbides [1]. The current development effort aims to advance the technology originally developed and demonstrated under Project Rover (1955-1973) for the NERVA (Nuclear Engine for Rocket Vehicle Application) [2].
Structure and Function of 4-Hydroxyphenylacetate Decarboxylase and Its Cognate Activating Enzyme.
Selvaraj, Brinda; Buckel, Wolfgang; Golding, Bernard T; Ullmann, G Matthias; Martins, Berta M
2016-01-01
4-Hydroxyphenylacetate decarboxylase (4Hpad) is the prototype of a new class of Fe-S cluster-dependent glycyl radical enzymes (Fe-S GREs) acting on aromatic compounds. The two-enzyme component system comprises a decarboxylase responsible for substrate conversion and a dedicated activating enzyme (4Hpad-AE). The decarboxylase uses a glycyl/thiyl radical dyad to convert 4-hydroxyphenylacetate into p-cresol (4-methylphenol) by a biologically unprecedented Kolbe-type decarboxylation. In addition to the radical dyad prosthetic group, the decarboxylase unit contains two [4Fe-4S] clusters coordinated by an extra small subunit of unknown function. 4Hpad-AE reductively cleaves S-adenosylmethionine (SAM or AdoMet) at a site-differentiated [4Fe-4S]2+/+ cluster (RS cluster) generating a transient 5'-deoxyadenosyl radical that produces a stable glycyl radical in the decarboxylase by the abstraction of a hydrogen atom. 4Hpad-AE binds up to two auxiliary [4Fe-4S] clusters coordinated by a ferredoxin-like insert that is C-terminal to the RS cluster-binding motif. The ferredoxin-like domain with its two auxiliary clusters is not vital for SAM-dependent glycyl radical formation in the decarboxylase, but facilitates a longer lifetime for the radical. This review describes the 4Hpad and cognate AE families and focuses on the recent advances and open questions concerning the structure, function and mechanism of this novel Fe-S-dependent class of GREs. © 2016 S. Karger AG, Basel.
Reiter-Owona, Ingrid; Grüner, Beate; Frosch, Matthias; Hoerauf, Achim; Kern, Peter; Tappe, Dennis
2009-01-01
Sera of 50 patients with either cystic (CE) or alveolar echinococcosis (AE) in different clinical stages were examined for the presence of anti-Echinococcus-antibodies. Antibody-screening was performed with ELISA, IHA and IFAT, and confirmatory testing was done by the commercialized E. multilocularis-specific Em2plus-ELISA versus an in-house E. multilocularis-specific Em10-ELISA. Sera with discrepant confirmatory results were subjected to a commercial Echinococcus IgG Western blot (WB). In sera from patients with CE, the Em2plus-ELISA showed cross-reactions in 23.5%, whereas the Em10-ELISA did not exhibit any cross-reactivity. Cross-reactivity paralleled active infection with high antibody titers in the screening assays. In sera from patients with AE, confirmation by both ELISAs was achieved in 57.6%, mostly in patients with an advanced stage of the disease and high antibody titers in the screening assays. False-negative reactions of both ELISAs occurred in 30.3%, mostly in patients who had low antibody levels in the screening tests. The Em2plus-ELISA exhibited fewer false-negative reactions than the Em10-ELISA. The WB confirmed the positive results of either assay and was the assay with the highest reliability at different stages of CE and AE, followed by the Em2plus-ELISA for AE. High antibody titers in the screening assays will favour the detection of species-specific antibodies in either form.
Yao, Shuyang; Zhi, Xiuyi; Wang, Ruotian; Qian, Kun; Hu, Mu
2016-01-01
Background Epidermal growth factor receptor (EGFR) mutations occur in about 50% of Asian patients with non‐small cell lung cancer (NSCLC). Patients with advanced NSCLC and EGFR mutations derive clinical benefit from treatment with EGFR‐tyrosine kinase inhibitors (TKIs). This study assessed the efficacy and safety of adjuvant icotinib without chemotherapy in EGFR‐mutated NSCLC patients undergoing resection of stage IB–IIIA. Methods Our retrospective study enrolled 20 patients treated with icotinib as adjuvant therapy. Survival factors were evaluated by univariate and Cox regression analysis. Results The median follow‐up time was 30 months (range 24–41). At the data cut‐off, five patients (25%) had recurrence or metastasis and one patient had died of the disease. The two‐year disease‐free survival (DFS) rate was 85%. No recurrence occurred in the high‐risk stage IB subgroup during the follow‐up period. In univariate analysis, the micropapillary pattern had a statistically significant effect on DFS (P = 0.040). Multivariate logistic regression analysis showed that there was no independent predictor. Drug related adverse events (AEs) occurred in nine patients (45.0%). The most common AEs were skin‐related events and diarrhea, but were relatively mild. No grade 3 AEs or occurrences of intolerable toxicity were observed. Conclusions Icotinib as adjuvant therapy is effective in patients harboring EGFR mutations after complete resection, with an acceptable AE profile. Further trials with larger sample sizes might confirm the efficiency of adjuvant TKI in selected patients. PMID:27766784
Reyes-Solis, Guadalupe Del Carmen; Saavedra-Rodriguez, Karla; Suarez, Adriana Flores; Black, William C
2014-10-01
The mosquito Aedes aegypti is the principal vector of dengue and yellow fever flaviviruses. Temephos is an organophosphate insecticide used globally to suppress Ae. aegypti larval populations but resistance has evolved in many locations. Quantitative Trait Loci (QTL) controlling temephos survival in Ae. aegypti larvae were mapped in a pair of F3 advanced intercross lines arising from temephos resistant parents from Solidaridad, México and temephos susceptible parents from Iquitos, Peru. Two sets of 200 F3 larvae were exposed to a discriminating dose of temephos and then dead larvae were collected and preserved for DNA isolation every two hours up to 16 hours. Larvae surviving longer than 16 hours were considered resistant. For QTL mapping, single nucleotide polymorphisms (SNPs) were identified at 23 single copy genes and 26 microsatellite loci of known physical positions in the Ae. aegypti genome. In both reciprocal crosses, Multiple Interval Mapping identified eleven QTL associated with time until death. In the Solidaridad×Iquitos (SLD×Iq) cross twelve were associated with survival but in the reciprocal IqxSLD cross, only six QTL were survival associated. Polymorphisms at acetylcholine esterase (AchE) loci 1 and 2 were not associated with either resistance phenotype suggesting that target site insensitivity is not an organophosphate resistance mechanism in this region of México. Temephos resistance is under the control of many metabolic genes of small effect and dispersed throughout the Ae. aegypti genome.
Reyes-Solis, Guadalupe del Carmen; Saavedra-Rodriguez, Karla; Suarez, Adriana Flores; Black, William C.
2014-01-01
Introduction The mosquito Aedes aegypti is the principal vector of dengue and yellow fever flaviviruses. Temephos is an organophosphate insecticide used globally to suppress Ae. aegypti larval populations but resistance has evolved in many locations. Methodology/Principal Findings Quantitative Trait Loci (QTL) controlling temephos survival in Ae. aegypti larvae were mapped in a pair of F3 advanced intercross lines arising from temephos resistant parents from Solidaridad, México and temephos susceptible parents from Iquitos, Peru. Two sets of 200 F3 larvae were exposed to a discriminating dose of temephos and then dead larvae were collected and preserved for DNA isolation every two hours up to 16 hours. Larvae surviving longer than 16 hours were considered resistant. For QTL mapping, single nucleotide polymorphisms (SNPs) were identified at 23 single copy genes and 26 microsatellite loci of known physical positions in the Ae. aegypti genome. In both reciprocal crosses, Multiple Interval Mapping identified eleven QTL associated with time until death. In the Solidaridad×Iquitos (SLD×Iq) cross twelve were associated with survival but in the reciprocal IqxSLD cross, only six QTL were survival associated. Polymorphisms at acetylcholine esterase (AchE) loci 1 and 2 were not associated with either resistance phenotype suggesting that target site insensitivity is not an organophosphate resistance mechanism in this region of México. Conclusions/Significance Temephos resistance is under the control of many metabolic genes of small effect and dispersed throughout the Ae. aegypti genome. PMID:25330200
Carpinteri, Alberto; Invernizzi, Stefano; Accornero, Federico
2013-01-01
We examine an application of Acoustic Emission (AE) technique for a probabilistic analysis in time and space of earthquakes, in order to preserve the valuable Italian Renaissance Architectural Complex named “The Sacred Mountain of Varallo.” Among the forty-five chapels of the Renaissance Complex, the structure of the Chapel XVII is of particular concern due to its uncertain structural condition and due to the level of stress caused by the regional seismicity. Therefore, lifetime assessment, taking into account the evolution of damage phenomena, is necessary to preserve the reliability and safety of this masterpiece of cultural heritage. A continuous AE monitoring was performed to assess the structural behavior of the Chapel. During the monitoring period, a correlation between peaks of AE activity in the masonry of the “Sacred Mountain of Varallo” and regional seismicity was found. Although the two phenomena take place on very different scales, the AE in materials and the earthquakes in Earth's crust, belong to the same class of invariance. In addition, an accurate finite element model, performed with DIANA finite element code, is presented to describe the dynamic behavior of Chapel XVII structure, confirming visual and instrumental inspections of regional seismic effects. PMID:24381511
Assimilation and regeneration of trace elements by marine copepods
Wang, W.-X.; Reinfelder, J.R.; Lee, B.-G.; Fisher, N.S.
1996-01-01
Assimilation efficiencies (AE) of five trace elements (Am, Cd, Co, Se, and Zn) and carbon by neritic copepods (Acartia tonsa and Temora longicornis) feeding at different food concentrations and on different food types (diatoms, green algae, flagellates, dinoflagellates, and Fe oxides) were measured with radiotracer techniques. Food concentration had little influence on AEs of C, Cd, Co, and Se within a range of 16-800 ?? C liter-1. AEs of Am and Zn were highest at low food concentrations (16-56 ??g C liter-1) but remained relatively constant when food levels exceeded 160 ??g C liter-1. Different algal diets had no major influence on AEs, which generally were in the order Cd > Se > Zn > Co > Am. Metals (Cd, Co, and Zn) were assimilated from Fe oxides with 50% less efficiency than from algal cells. Element regeneration into the dissolved phase was a significant route for the release of ingested elements by copepods and increased with increased food concentration. Element regeneration rates for Cd, Se, and Zn were comparable to the regeneration rates of major nutrients such as P (30-70% daily). Retention half-times of elements in decomposing fecal pellets ranged from 10 d (Am). The efficient assimilation and regeneration of Cd, Se, and Zn can significantly lengthen the residence time of these elements in ocean surface waters.
The determination of mercury in mushrooms by CV-AAS and ICP-AES techniques.
Jarzynska, Grazyna; Falandysz, Jerzy
2011-01-01
This research presents an example of an excellent applied study on analytical problems due to hazardous mercury determination in environmental materials and validity of published results on content of this element in wild growing mushrooms. The total mercury content has been analyzed in a several species of wild-grown mushrooms and some herbal origin certified reference materials, using two analytical methods. One method was commonly known and well validated the cold-vapour atomic absorption spectroscopy (CV-AAS) after a direct sample pyrolysis coupled to the gold wool trap, which was a reference method. A second method was a procedure that involved a final mercury measurement using the inductively-coupled plasma atomic emission spectroscopy (ICP-AES) at λ 194.163 nm, which was used by some authors to report on a high mercury content of a large sets of wild-grown mushrooms. We found that the method using the ICP-AES at λ 194.163 nm gave inaccurate and imprecise results. The results of this study imply that because of unsuitability of total mercury determination using the ICP-AES at λ 194.163 nm, the reports on great concentrations of this metal in a large sets of wild-grown mushrooms, when examined using this method, have to be studied with caution, since data are highly biased.
Survey of current situation in radiation belt modeling
NASA Technical Reports Server (NTRS)
Fung, Shing F.
2004-01-01
The study of Earth's radiation belts is one of the oldest subjects in space physics. Despite the tremendous progress made in the last four decades, we still lack a complete understanding of the radiation belts in terms of their configurations, dynamics, and detailed physical accounts of their sources and sinks. The static nature of early empirical trapped radiation models, for examples, the NASA AP-8 and AE-8 models, renders those models inappropriate for predicting short-term radiation belt behaviors associated with geomagnetic storms and substorms. Due to incomplete data coverage, these models are also inaccurate at low altitudes (e.g., <1000 km) where many robotic and human space flights occur. The availability of radiation data from modern space missions and advancement in physical modeling and data management techniques have now allowed the development of new empirical and physical radiation belt models. In this paper, we will review the status of modern radiation belt modeling. Published by Elsevier Ltd on behalf of COSPAR.
Patient Participation and the Use of Ehealth Tools for Pharmacoviligance.
Berrewaerts, Joëlle; Delbecque, Laure; Orban, Pierre; Desseilles, Martin
2016-01-01
In recent years, pharmacovigilance has undergone some major changes. First, the patient's active role in identifying and describing adverse drug reactions (ADRs) has gained recognition. Second, pharmacovigilance has increasingly incorporated information and communications technology (ICT). Patients can now upload their own reports of ADRs online. Data on intensive medication monitoring are now collected via the Internet and smartphones. Worldwide collection of AEs using smart phones might become the leading technique in Low and Middle Income Countries where broad mobile phone service can be managed cheaper than Internet communication. At the same time, researchers are exploring the potential for data sharing via online forums and Internet search engines. In particular we synthetize the Pros and cons of the various methods for gathering pharmacovigilance data (i.e., Web-based spontaneous reporting of adverse drug reactions; Intensive drug monitoring studies; Analysis of online forum postings; Use of mobile phone systems to monitor drug effects). This article describes these advances and highlights their respective contributions.
Patient Participation and the Use of Ehealth Tools for Pharmacoviligance
Berrewaerts, Joëlle; Delbecque, Laure; Orban, Pierre; Desseilles, Martin
2016-01-01
In recent years, pharmacovigilance has undergone some major changes. First, the patient’s active role in identifying and describing adverse drug reactions (ADRs) has gained recognition. Second, pharmacovigilance has increasingly incorporated information and communications technology (ICT). Patients can now upload their own reports of ADRs online. Data on intensive medication monitoring are now collected via the Internet and smartphones. Worldwide collection of AEs using smart phones might become the leading technique in Low and Middle Income Countries where broad mobile phone service can be managed cheaper than Internet communication. At the same time, researchers are exploring the potential for data sharing via online forums and Internet search engines. In particular we synthetize the Pros and cons of the various methods for gathering pharmacovigilance data (i.e., Web-based spontaneous reporting of adverse drug reactions; Intensive drug monitoring studies; Analysis of online forum postings; Use of mobile phone systems to monitor drug effects). This article describes these advances and highlights their respective contributions. PMID:27148052
Georgiades, Anna; Rijsdijk, Fruhling; Kane, Fergus; Rebollo-Mesa, Irene; Kalidindi, Sridevi; Schulze, Katja K; Stahl, Daniel; Walshe, Muriel; Sahakian, Barbara J; McDonald, Colm; Hall, Mei-Hua; Murray, Robin M; Kravariti, Eugenia
2016-06-01
Twin studies have lacked statistical power to apply advanced genetic modelling techniques to the search for cognitive endophenotypes for bipolar disorder. To quantify the shared genetic variability between bipolar disorder and cognitive measures. Structural equation modelling was performed on cognitive data collected from 331 twins/siblings of varying genetic relatedness, disease status and concordance for bipolar disorder. Using a parsimonious AE model, verbal episodic and spatial working memory showed statistically significant genetic correlations with bipolar disorder (rg = |0.23|-|0.27|), which lost statistical significance after covarying for affective symptoms. Using an ACE model, IQ and visual-spatial learning showed statistically significant genetic correlations with bipolar disorder (rg = |0.51|-|1.00|), which remained significant after covarying for affective symptoms. Verbal episodic and spatial working memory capture a modest fraction of the bipolar diathesis. IQ and visual-spatial learning may tap into genetic substrates of non-affective symptomatology in bipolar disorder. © The Royal College of Psychiatrists 2016.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nelsen, Nicholas H.; Kolb, James D.; Kulkarni, Akshay G.
Mechanical component response to shock environments must be predictable in order to ensure reliability and safety. Whether the shock input results from accidental drops during transportation to projectile impact scenarios, the system must irreversibly transition into a safe state that is incapable of triggering the component . With this critical need in mind, the 2017 Nuclear Weapons Summer Product Realization Institute (NW SPRINT) program objective sought the design of a passive shock failsafe with emphasis on additively manufactured (AM) components. Team Advanced and Exploratory (A&E) responded to the challenge by designing and delivering multiple passive shock sensing mech anisms thatmore » activate within a prescribed mechanical shock threshold. These AM failsafe designs were tuned and validated using analytical and computational techniques including the shock response spectrum (SRS) and finite element analysis (FEA). After rapid prototyping, the devices experienced physical shock tests conducted on Sandia drop tables to experimentally verify performance. Keywords: Additive manufacturing, dynamic system, failsafe, finite element analysis, mechanical shock, NW SPRINT, shock respon se spectrum« less
NASA Astrophysics Data System (ADS)
Ahmad, Nabihah; Rifen, A. Aminurdin M.; Helmy Abd Wahab, Mohd
2016-11-01
Automated Teller Machine (ATM) is an electronic banking outlet that allows bank customers to complete a banking transactions without the aid of any bank official or teller. Several problems are associated with the use of ATM card such card cloning, card damaging, card expiring, cast skimming, cost of issuance and maintenance and accessing customer account by third parties. The aim of this project is to give a freedom to the user by changing the card to biometric security system to access the bank account using Advanced Encryption Standard (AES) algorithm. The project is implemented using Field Programmable Gate Array (FPGA) DE2-115 board with Cyclone IV device, fingerprint scanner, and Multi-Touch Liquid Crystal Display (LCD) Second Edition (MTL2) using Very High Speed Integrated Circuit Hardware (VHSIC) Description Language (VHDL). This project used 128-bits AES for recommend the device with the throughput around 19.016Gbps and utilized around 520 slices. This design offers a secure banking transaction with a low rea and high performance and very suited for restricted space environments for small amounts of RAM or ROM where either encryption or decryption is performed.
Yeruva, Dileep Kumar; Jukuri, Srinivas; Velvizhi, G; Naresh Kumar, A; Swamy, Y V; Venkata Mohan, S
2015-01-01
The present study evaluates the sequential integration of two advanced biological treatment methods viz., sequencing batch reactor (SBR) and bioelectrochemical treatment systems (BET) for the treatment of real-field petrochemical wastewater (PCW). Initially two SBR reactors were operated in aerobic (SBR(Ae)) and anoxic (SBR(Ax)) microenvironments with an organic loading rate (OLR) of 9.68 kg COD/m(3)-day. Relatively, SBR(Ax) showed higher substrate degradation (3.34 kg COD/m(3)-day) compared to SBR(Ae) (2.9 kg COD/m(3)-day). To further improve treatment efficiency, the effluents from SBR process were fed to BET reactors. BET(Ax) depicted higher SDR (1.92 kg COD/m(3)-day) with simultaneous power generation (17.12 mW/m(2)) followed by BET(Ae) (1.80 kg COD/m(3)-day; 14.25 mW/m(2)). Integrating both the processes documented significant improvement in COD removal efficiency due to the flexibility of combining multiple microenvironments sequentially. Results were supported with GC-MS and FTIR, which confirmed the increment in biodegradability of wastewater. Copyright © 2015 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Geng, R. L.; Golden, B. A.; Kushnick, P.
2011-07-01
One of the major goals of ILC SRF cavity R&D is to develop industrial capabilities of cavity manufacture and processing in all three regions. In the past several years, Jefferson Lab, in collaboration with Fermi National Accelerator Laboratory, has processed and tested all the 9-cell cavities of the first batch (4 cavities) and second batch (6 cavities) production cavities manufactured by Advanced Energy Systems Inc. (AES). Over the course, close information feedback was maintained, resulting in changes in fabrication and processing procedures. A light buffered chemical polishing was introduced, removing the weld splatters that could not be effectively removed bymore » heavy EP alone. An 800 Celsius 2 hour vacuum furnace heat treatment procedure replaced the original 600 Celsius 10 hour procedure. Four out of the six 9-cell cavities of the second production bath achieved a gradient of 36-41 MV/m at a Q0 of more than 8E9 at 35 MV/m. This result validated AES as the first ''ILC certified'' industrial vendor in the US for ILC cavity manufacture.« less
Identifying and managing the adverse effects of immune checkpoint blockade
Winer, Arthur; Bodor, J. Nicholas
2018-01-01
Immunotherapy has revolutionized the field of oncology. By inhibiting the cytotoxic T-lymphocyte-associated protein (CTLA-4) and programmed death-1 (PD-1) immune checkpoint pathways, multiple studies have demonstrated greatly improved survival in locally advanced and metastatic cancers including melanoma, renal, lung, gastric, and hepatocellular carcinoma. Trials in other malignancies are ongoing, and undoubtedly the number of drugs in this space will grow beyond the six currently approved by the Food and Drug Administration. However, by altering the immune response to fight cancer, a new class of side effects has emerged known as immune-related adverse events (irAEs). These adverse events are due to overactivation of the immune system in almost any organ of the body, and can occur at any point along a patient’s treatment course. irAEs such as endocrinopathies (thyroiditis), colitis, and pneumonitis may occur more commonly. However, other organs such as the liver, heart, or brain may also be affected by immune overactivation and any of these side effects may become life threatening. This review presents an approach to promptly recognize and manage these toxicities, to hopefully minimize morbidity and mortality from irAEs. PMID:29593893
Aviation Electrician's Mate 1 & C. Rate Training Manual and Nonresident Career Course.
ERIC Educational Resources Information Center
Naval Education and Training Command, Pensacola, FL.
One of a series of training manuals prepared for enlisted personnel in the Navy and Naval Reserve who are studying for advancement in the Aviation Electrician's Mate (AE) rating, this text is based upon the Navy's professional occupational standards for AEI and AEC. Contents include a 10-chapter text followed by a subject index and the associated…
1994-05-01
1979. 110 42. Williams, A.E., and Saravane, I., Debris Chlaraiatiaon SUt&y NRL Letter Rleport 4680-196,1990. 43. Weanzel, A.B., and Dean , J.K., Behind...Commerce, National Bureau of Standards, Washington, D.C., 1971. 52. Stull , D.X, and Sinke, G.C., *Thermodynamic Properties of the Elements", in Advances in
Chisaki, Yugo; Nakamura, Nobuhiko; Yano, Yoshitaka
2017-01-01
The purpose of this study was to propose a time-series modeling and simulation (M&S) strategy for probabilistic cost-effective analysis in cancer chemotherapy using a Monte-Carlo method based on data available from the literature. The simulation included the cost for chemotherapy, for pharmaceutical care for adverse events (AEs) and other medical costs. As an application example, we describe the analysis for the comparison of four regimens, cisplatin plus irinotecan, carboplatin plus paclitaxel, cisplatin plus gemcitabine (GP), and cisplatin plus vinorelbine, for advanced non-small cell lung cancer. The factors, drug efficacy explained by overall survival or time to treatment failure, frequency and severity of AEs, utility value of AEs to determine QOL, the drugs' and other medical costs in Japan, were included in the model. The simulation was performed and quality adjusted life years (QALY) and incremental cost-effectiveness ratios (ICER) were calculated. An index, percentage of superiority (%SUP) which is the rate of the increased cost vs. QALY-gained plots within the area of positive QALY-gained and also below some threshold values of the ICER, was calculated as functions of threshold values of the ICER. An M&S process was developed, and for the simulation example, the GP regimen was the most cost-effective, in case of threshold values of the ICER=$70000/year, the %SUP for the GP are more than 50%. We developed an M&S process for probabilistic cost-effective analysis, this method would be useful for decision-making in choosing a cancer chemotherapy regimen in terms of pharmacoeconomic.
Predictive Value of Early Skin Rash in Cetuximab-Based Therapy of Advanced Biliary Tract Cancer.
Rubovszky, Gábor; Budai, Barna; Ganofszky, Erna; Horváth, Zsolt; Juhos, Éva; Madaras, Balázs; Nagy, Tünde; Szabó, Eszter; Pintér, Tamás; Tóth, Erika; Nagy, Péter; Láng, István; Hitre, Erika
2018-04-01
Randomized trials in advanced biliary tract cancer (BTC) did not show benefit of cetuximab addition over chemotherapy. This is probably due to the lack of predictive biomarkers. The aim of this study was to explore possible predictive factors. Between 2009 and 2014, 57 patients were treated in 3-week cycles with cetuximab (250 mg/m 2 /week, loading dose: 400 mg/m 2 ), gemcitabine (1000 mg/m 2 on day 1 and 8), and capecitabine (1300 mg/m 2 /day on days 1-14). The objective response rate (ORR), progression-free (PFS) and overall survival (OS) and the adverse events (AEs) were evaluated. An exploratory analysis was performed to find possible predictive factors on clinicopathological characteristics, routine laboratory parameters and early AEs, which occurred within 2 months from the beginning of treatment. The ORR was 21%. The median PFS and OS were 34 (95% CI: 24-40) and 54 (43-67) weeks, respectively. The most frequent AEs were skin toxicities. In univariate analysis performance status, previous stent implantation, thrombocyte count at the start of therapy, early neutropenia and skin rash statistically significantly influenced the ORR, PFS and/or OS. In multivariate Cox regression analysis only normal thrombocyte count at treatment start and early acneiform rash were independent markers of longer survival. In patients showing early skin rash compared to the others the median PFS was 39 vs. 13 weeks and the median OS was 67 vs. 26 weeks, respectively. It is suggested that early skin rash can be used as a biomarker to select patients who would benefit from the treatment with cetuximab plus chemotherapy.
Vail, D.M.; von Euler, H.; Rusk, A.W.; Barber, L.; Clifford, C.; Elmslie, R.; Fulton, L.; Hirschberger, J.; Klein, M.; London, C.; Martano, M.; McNiel, E.A.; Morris, J.S.; Northrup, N.; Phillips, B.; Polton, G.; Post, G.; Rosenberg, M.; Ruslander, D.; Sahora, A.; Siegel, S.; Thamm, D.; Westberg, S.; Winter, J.; Khanna, C.
2013-01-01
Background Effective treatments for dogs with advanced stage mast cell tumors (MCT) remain a pressing need. A micellar formulation of paclitaxel (paclitaxel [micellar]) has shown promise in early-phase studies. Hypothesis/Objectives The objective was to demonstrate greater activity for paclitaxel (micellar) compared with lomustine. The null hypothesis was μp = μL (ie, proportion of responders for the paclitaxel [micellar] and lomustine groups, respectively). Animals Two hundred and fifty-two dogs with advanced stage nonresectable grade 2 or 3 MCT. Methods Prospective multicenter randomized double-blind positive-controlled clinical trial. The primary endpoint was confirmed overall response rate (CORR) at 14 weeks. A secondary endpoint, biologic observed response rate (BORR), also was calculated. Safety was assessed by the characterization and grading of adverse events (AE). Results Overall CORR (7% versus 1%; P = .048) and BORR (23% versus 10%; P = .012) were greater for paclitaxel (micellar) compared with lomustine. Paclitaxel (micellar)-treated dogs were 6.5 times more likely to have a confirmed response and 3.1 times more likely to experience a biologic observed response. The majority of AE with paclitaxel (micellar) were transient and clinically manageable. Twenty-seven dogs (33%) receiving lomustine were discontinued because of hepatopathy compared with 3 dogs (2%) receiving paclitaxel (micellar) (P < .0001; odds ratio 26.7). Conclusions and Clinical Importance Paclitaxel (micellar)’s activity and safety profile are superior to lomustine. The addition of an active and novel taxane to the veterinary armamentarium could fill a substantial need and, as its mechanism of action and AE profile do not overlap with currently available TKI, its availability could lead to effective combination protocols. PMID:22390318
Suder, A; Ang, J E; Kyle, F; Harris, D; Rudman, S; Kristeleit, R; Solca, F; Uttenreuther-Fischer, M; Pemberton, K; Pelling, K; Schnell, D; de Bono, J; Spicer, J
2015-11-01
This phase I study evaluated afatinib, an irreversible ErbB family blocker, plus paclitaxel in patients with advanced solid tumours likely to express human epidermal growth factor receptor (HER1/EGFR) or HER2. Oral afatinib was combined with intravenous paclitaxel (80mg/m(2); days 1, 8 and 15 every four weeks) starting at 20mg once daily and escalated to 40 and 50mg in successive cohorts of ⩾3 patients. The primary objective was to determine the maximum tolerated dose (MTD) of afatinib combined with paclitaxel. Secondary objectives included safety, pharmacokinetics and antitumour activity. Sixteen patients were treated. Dose-limiting toxicities with afatinib 50mg were fatigue and mucositis. The MTD was determined as afatinib 40mg with paclitaxel 80mg/m(2), which proved tolerable with repeated dosing. Frequent adverse events (AEs) included diarrhoea (94%), fatigue (81%), rash/acne (81%), decreased appetite (69%) and inflammation of mucosal membranes (69%); no grade 4 treatment-related AEs were observed. Five (31%) confirmed partial responses were observed in patients with non-small cell lung cancer (n=3), oesophageal cancer and cholangiocarcinoma; eight (50%) patients remained on study for ⩾6months. Pharmacokinetic parameters of afatinib and paclitaxel were similar for single administration or in combination. The MTD and recommended phase II dose of once-daily afatinib combined with paclitaxel 80mg/m(2) (days 1, 8 and 15 every four weeks) was 40mg. AEs at or below this dose were generally manageable with repeated dosing. No pharmacokinetic interactions were observed. This combination demonstrated promising antitumour activity. ClinicalTrials.gov, NCT00809133. Copyright © 2015 Elsevier Ltd. All rights reserved.
Dib, Ikram; Tits, Monique; Angenot, Luc; Wauters, Jean Noel; Assaidi, Asmae; Mekhfi, Hassane; Aziz, Mohammed; Bnouham, Mohammed; Legssyer, Abdelkhaleq; Frederich, Michel; Ziyyat, Abderrahim
2017-07-12
Artemisia campestris L. (Asteraceae) has many traditional uses, among which treatment of diabetes and hypertension. This study was conducted in order to confirm the antihypertensive and hypotensive effects of A. campestris L. aqueous extract (AcAE) and to explore the underlying mechanism of action of its vasorelaxant effect, besides the acute toxicity. Also, the chemical composition of AcAE was investigated. the chemical content of AcAE was determined by using HPLC and NMR techniques. The antihypertensive effect was assessed indirectly by tail-cuff method on L-NAME induced hypertensive rats, while the hypotensive action was monitored intravenously by invasive method on normotensive rats. The vasorelaxant effect and vascular mechanism of action were studied in the presence of antagonists and blockers on aorta isolated from normotensive rats. On the other side, the acute toxicity was studied by oral feeding of extract to the mice. The global phytochemical profile of AcAE reveals the presence of several polyphenols as main components. A. campestris L. infusion was characterized by mono- and di-cinnamoyl compounds, with 3,5-dicaffeoylquinic (isochlorogenic A) acid being the main compound, followed by 5-caffeoylquinic (chlorogenic) acid. Vicenin-2 (apigenin 6,8-di-C-glucoside) appeared to be the most abundant compound among flavonoids. The daily treatment with AcAE at 150mg/kg/day prevented the installation of hypertension on L-NAME hypertensive rats, and reduced SBP from 172mmHg up to 144mmHg. At the dose 40mg/kg, AcAE provoked reduction of systolic (SBP), diastolic (DBP) and mean arterial pressure (MAP), without affecting the heart rate. Also, AcAE (10 -2 -2mg/ml) relaxed the precontracted aorta by 95.8±1.3%. The denudation and preincubation of aorta with atropine, calmidazolium, L-NAME, hydroxycobalamin, ODQ, 8-RP-Br-PET-cGMP, thapsigargin and verapamil attenuated the vasorelaxant response, while the pre-treatment with 4-AP, TEA, glibenclamide and BaCl 2 did not alter this effect. The oral administration of AcAE (0-6g/kg) reveals no mortality or toxicity. our study proved that AcAE possess an important antihypertensive, hypotensive and vasorelaxant effect, which is mediated via calmodulin-NO-cGC-PKG pathway, and via inhibition of calcium influx through voltage-operated calcium channels and activation of intracellular calcium mobilization into sarcoplasmic reticulum. Therefore, our findings give first evidence about the traditional use of A. campestris L. as antihypertensive plant. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
AE monitoring instrumentation for high performance superconducting dipoles and quadrupoles, Phase 2
NASA Astrophysics Data System (ADS)
Iwasa, Y.
1986-01-01
In the past year and a half, attention has been focused on the development of instrumentation for on-line monitoring of high-performance superconducting dipoles and quadrupoles. This instrumentation has been completed and satisfactorily demonstrated on a prototype Fermi dipole. Conductor motion is the principal source of acoustic emission (AE) and the major cause of quenches in the dipole, except during the virgin run when other sources are also present. The motion events are mostly microslips. The middle of the magnet is most susceptible to quenches. This result agrees with the peak field location in the magnet. In the virgin state the top and bottom of the magnet appeared acoustically similar but diverged after training, possibly due to minute structural asymmetry, for example differences in clamping and welding strength; however, the results do not indicate any major structural defects. There is good correlation between quench current and AE starting current. The correlation is reasonable if mechanical disturbances are indeed responsible for quench. Based on AE cumulative history, the average frictional power dissipation in the whole dipole winding is estimated to be approx. 10 (MU)W cm(-3). We expect to implement the following in the next phase of this project: Application of room-temperature techniques to detecting structural defects in the dipole; application of the system to other dipoles and quadrupoles in the same series to compare their performances; and further investigation of AE starting current approx. quench current relationship. Work has begun on the room temperature measurements. Preliminary Stress Wave Factor measurements have been made on a model dipole casing.
Pacheco-Salazar, O F; Wakayama, Shuichi; Sakai, Takenobu; Cauich-Rodríguez, J V; Ríos-Soberanis, C R; Cervantes-Uc, J M
2015-06-01
In this work, the effect of the incorporation of core-shell particles on the fracture mechanisms of the acrylic bone cements by using acoustic emission (AE) technique during the quasi-static compression mechanical test was investigated. Core-shell particles were composed of a poly(butyl acrylate) (PBA) rubbery core and a methyl methacrylate/styrene copolymer (P(MMA-co-St)) outer glassy shell. Nanoparticles were prepared with different core-shell ratio (20/80, 30/70, 40/60 and 50/50) and were incorporated into the solid phase of bone cement at several percentages (5, 10 and 15 wt%). It was observed that the particles exhibited a spherical morphology averaging ca. 125 nm in diameter, and the dynamic mechanical analysis (DMA) thermograms revealed the desired structuring pattern of phases associated with core-shell structures. A fracture mechanism was proposed taking into account the detected AE signals and the scanning electron microscopy (SEM) micrographs. In this regard, core-shell nanoparticles can act as both additional nucleation sites for microcracks (and crazes) and to hinder the microcrack propagation acting as a barrier to its growth; this behavior was presented by all formulations. Cement samples containing 15 wt% of core-shell nanoparticles, either 40/60 or 50/50, were fractured at 40% deformation. This fact seems related to the coalescence of microcracks after they surround the agglomerates of core-shell nanoparticles to continue growing up. This work also demonstrated the potential of the AE technique to be used as an accurate and reliable detection tool for quasi-static compression test in acrylic bone cements. Copyright © 2015 Elsevier Ltd. All rights reserved.
Separation techniques for the clean-up of radioactive mixed waste for ICP-AES/ICP-MS analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swafford, A.M.; Keller, J.M.
1993-03-17
Two separation techniques were investigated for the clean-up of typical radioactive mixed waste samples requiring elemental analysis by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) or Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). These measurements frequently involve regulatory or compliance criteria which include the determination of elements on the EPA Target Analyte List (TAL). These samples usually consist of both an aqueous phase and a solid phase which is mostly an inorganic sludge. Frequently, samples taken from the waste tanks contain high levels of uranium and thorium which can cause spectral interferences in ICP-AES or ICP-MS analysis. The removal of these interferences ismore » necessary to determine the presence of the EPA TAL elements in the sample. Two clean-up methods were studied on simulated aqueous waste samples containing the EPA TAL elements. The first method studied was a classical procedure based upon liquid-liquid extraction using tri-n- octylphosphine oxide (TOPO) dissolved in cyclohexane. The second method investigated was based on more recently developed techniques using extraction chromatography; specifically the use of a commercially available Eichrom TRU[center dot]Spec[trademark] column. Literature on these two methods indicates the efficient removal of uranium and thorium from properly prepared samples and provides considerable qualitative information on the extraction behavior of many other elements. However, there is a lack of quantitative data on the extraction behavior of elements on the EPA Target Analyte List. Experimental studies on these two methods consisted of determining whether any of the analytes were extracted by these methods and the recoveries obtained. Both methods produced similar results; the EPA target analytes were only slightly or not extracted. Advantages and disadvantages of each method were evaluated and found to be comparable.« less
Almessiere, M A; Altuwiriqi, R; Gondal, M A; AlDakheel, R K; Alotaibi, H F
2018-08-01
In this work, we analysed human fingernails of people who suffer from vitamin D deficiency using the laser-induced breakdown spectroscopy(LIBS) and inductively coupled plasma atomic emission spectroscopy (ICP-AES)techniques. The measurements have been conducted on 71 nail samples collected randomly from volunteers of different genders and ages ranged between 20 and 50 years. The main aim of this study is to find the correlation between vitamin D deficiency and the intensity of some dominated lines in the LIBS spectra. A LIBS spectrum consists of dominant lines of fifteen elements including calcium, magnesium, sodium, potassium, titanium, iron, chloride, sulphur, copper, chromium, zinc, nitrogen, phosphor, and oxygen. By recording the spectrum in specific ranges and focusing on calcium, magnesium, sodium, and potassium, we found a correlation between the intensity of the potassium (K) lines at (766.5 and 769.9 nm)and vitamin D level in both age groups (20 and 25 years old), with weak correlation for the calcium (Ca), magnesium (Mg), and sodium (Na) lines. To verify the validity of the LIBS results, we analysed the nail samples with ICP, a standard analytical technique. The elements detected with our LIBS technique are in a good agreement with those identified by ICP-AES. From the health and physiological perspectives, the LIBS system, which is used for spectral analysis in this work, is appropriate for diagnostic purposes such as to find the correlation between vitamin D deficiency and potassium content, especially for hypertensive patients who simultaneously take potassium-based medication and vitamin D supplement. Copyright © 2018 Elsevier B.V. All rights reserved.
Schwaitzberg, Steven D; Dorozhkin, Denis; Sankaranarayanan, Ganesh; Matthes, Kai; Jones, Daniel B; De, Suvranu
2016-01-01
A virtual translumenal endoscopic surgical trainer (VTEST) is being developed to accelerate the development of natural orifice translumenal endoscopic surgery (NOTES) procedures and devices in a safe and risk-free environment. For a rapidly developing field such as NOTES, a needs analysis must be conducted regularly to discover emerging research trends and areas of potential high impact for a virtual simulator. This paper presents a survey-based study which follows a similar study conducted by this group in 2011 (Sankaranarayanan et al. in Surg Endosc 27:1607-1616, 2013). A 32-point questionnaire was distributed at the 2012 Natural Orifice Surgery Consortium for Assessment and Research annual meeting. These data were subsequently augmented by an identical online survey, targeted at the members of the American Society for Gastrointestinal Endoscopy and the Society of American Gastrointestinal and Endoscopic Surgeons, and analyzed. Twenty-eight NOTES experts participated in the 2012 study. Cholecystectomy (CE) procedure remained the most commonly performed NOTES technique, with 18 positive responses (64%). In contrast to 2011, the popularity of the NOTES appendectomy (AE) was significantly lower, with only 2 (7%) instances (CE vs. AE, p < 0.001), while the number of peroral endoscopic myotomy (POEM, PE) cases had increased significantly, with 11 (39%) positive responses, respectively (PE vs. AE, p = 0.013). Strong preference toward hybrid rather than pure NOTES techniques (82 vs. 11%, p < 0.001) was also expressed. Other responses were similar to those in the 2011 study, with the VTEST™ utility in developing and testing new techniques and instruments ranked particularly high. Based on the results of this study, a decision was made to focus exclusively on the transvaginal hybrid NOTES cholecystectomy procedure, including both rigid and flexible scope techniques. The importance of developing a virtual NOTES simulator was reaffirmed, with POEM identified as a promising candidate for future simulator development.
Bergstrom, Kirk S. B.; Kissoon-Singh, Vanessa; Gibson, Deanna L.; Ma, Caixia; Montero, Marinieve; Sham, Ho Pan; Ryz, Natasha; Huang, Tina; Velcich, Anna; Finlay, B. Brett; Chadee, Kris; Vallance, Bruce A.
2010-01-01
Despite recent advances in our understanding of the pathogenesis of attaching and effacing (A/E) Escherichia coli infections, the mechanisms by which the host defends against these microbes are unclear. The goal of this study was to determine the role of goblet cell-derived Muc2, the major intestinal secretory mucin and primary component of the mucus layer, in host protection against A/E pathogens. To assess the role of Muc2 during A/E bacterial infections, we inoculated Muc2 deficient (Muc2−/−) mice with Citrobacter rodentium, a murine A/E pathogen related to diarrheagenic A/E E. coli. Unlike wildtype (WT) mice, infected Muc2−/− mice exhibited rapid weight loss and suffered up to 90% mortality. Stool plating demonstrated 10–100 fold greater C. rodentium burdens in Muc2−/− vs. WT mice, most of which were found to be loosely adherent to the colonic mucosa. Histology of Muc2−/− mice revealed ulceration in the colon amid focal bacterial microcolonies. Metabolic labeling of secreted mucins in the large intestine demonstrated that mucin secretion was markedly increased in WT mice during infection compared to uninfected controls, suggesting that the host uses increased mucin release to flush pathogens from the mucosal surface. Muc2 also impacted host-commensal interactions during infection, as FISH analysis revealed C. rodentium microcolonies contained numerous commensal microbes, which was not observed in WT mice. Orally administered FITC-Dextran and FISH staining showed significantly worsened intestinal barrier disruption in Muc2−/− vs. WT mice, with overt pathogen and commensal translocation into the Muc2−/− colonic mucosa. Interestingly, commensal depletion enhanced C. rodentium colonization of Muc2−/− mice, although colonic pathology was not significantly altered. In conclusion, Muc2 production is critical for host protection during A/E bacterial infections, by limiting overall pathogen and commensal numbers associated with the colonic mucosal surface. Such actions limit tissue damage and translocation of pathogenic and commensal bacteria across the epithelium. PMID:20485566
Systems pharmacology augments drug safety surveillance
Lorberbaum, Tal; Nasir, Mavra; Keiser, Michael J.; Vilar, Santiago; Hripcsak, George; Tatonetti, Nicholas P.
2014-01-01
Small molecule drugs are the foundation of modern medical practice yet their use is limited by the onset of unexpected and severe adverse events (AEs). Regulatory agencies rely on post-marketing surveillance to monitor safety once drugs are approved for clinical use. Despite advances in pharmacovigilance methods that address issues of confounding bias, clinical data of AEs are inherently noisy. Systems pharmacology– the integration of systems biology and chemical genomics – can illuminate drug mechanisms of action. We hypothesize that these data can improve drug safety surveillance by highlighting drugs with a mechanistic connection to the target phenotype (enriching true positives) and filtering those that do not (depleting false positives). We present an algorithm, the modular assembly of drug safety subnetworks (MADSS), to combine systems pharmacology and pharmacovigilance data and significantly improve drug safety monitoring for four clinically relevant adverse drug reactions. PMID:25670520
Rochefort, Christian M; Buckeridge, David L; Tanguay, Andréanne; Biron, Alain; D'Aragon, Frédérick; Wang, Shengrui; Gallix, Benoit; Valiquette, Louis; Audet, Li-Anne; Lee, Todd C; Jayaraman, Dev; Petrucci, Bruno; Lefebvre, Patricia
2017-02-16
Adverse events (AEs) in acute care hospitals are frequent and associated with significant morbidity, mortality, and costs. Measuring AEs is necessary for quality improvement and benchmarking purposes, but current detection methods lack in accuracy, efficiency, and generalizability. The growing availability of electronic health records (EHR) and the development of natural language processing techniques for encoding narrative data offer an opportunity to develop potentially better methods. The purpose of this study is to determine the accuracy and generalizability of using automated methods for detecting three high-incidence and high-impact AEs from EHR data: a) hospital-acquired pneumonia, b) ventilator-associated event and, c) central line-associated bloodstream infection. This validation study will be conducted among medical, surgical and ICU patients admitted between 2013 and 2016 to the Centre hospitalier universitaire de Sherbrooke (CHUS) and the McGill University Health Centre (MUHC), which has both French and English sites. A random 60% sample of CHUS patients will be used for model development purposes (cohort 1, development set). Using a random sample of these patients, a reference standard assessment of their medical chart will be performed. Multivariate logistic regression and the area under the curve (AUC) will be employed to iteratively develop and optimize three automated AE detection models (i.e., one per AE of interest) using EHR data from the CHUS. These models will then be validated on a random sample of the remaining 40% of CHUS patients (cohort 1, internal validation set) using chart review to assess accuracy. The most accurate models developed and validated at the CHUS will then be applied to EHR data from a random sample of patients admitted to the MUHC French site (cohort 2) and English site (cohort 3)-a critical requirement given the use of narrative data -, and accuracy will be assessed using chart review. Generalizability will be determined by comparing AUCs from cohorts 2 and 3 to those from cohort 1. This study will likely produce more accurate and efficient measures of AEs. These measures could be used to assess the incidence rates of AEs, evaluate the success of preventive interventions, or benchmark performance across hospitals.
Eriksson, Robert; Werge, Thomas; Jensen, Lars Juhl; Brunak, Søren
2014-04-01
Data collected for medical, filing and administrative purposes in electronic patient records (EPRs) represent a rich source of individualised clinical data, which has great potential for improved detection of patients experiencing adverse drug reactions (ADRs), across all approved drugs and across all indication areas. The aim of this study was to take advantage of techniques for temporal data mining of EPRs in order to detect ADRs in a patient- and dose-specific manner. We used a psychiatric hospital's EPR system to investigate undesired drug effects. Within one workflow the method identified patient-specific adverse events (AEs) and links these to specific drugs and dosages in a temporal manner, based on integration of text mining results and structured data. The structured data contained precise information on drug identity, dosage and strength. When applying the method to the 3,394 patients in the cohort, we identified AEs linked with a drug in 2,402 patients (70.8 %). Of the 43,528 patient-specific drug substances prescribed, 14,736 (33.9 %) were linked with AEs. From these links we identified multiple ADRs (p < 0.05) and found them to occur at similar frequencies, as stated by the manufacturer and in the literature. We showed that drugs displaying similar ADR profiles share targets, and we compared submitted spontaneous AE reports with our findings. For nine of the ten most prescribed antipsychotics in the patient population, larger doses were prescribed to sedated patients than non-sedated patients; five antipsychotics [corrected] exhibited a significant difference (p<0.05). Finally, we present two cases (p < 0.05) identified by the workflow. The method identified the potentially fatal AE QT prolongation caused by methadone, and a non-described likely ADR between levomepromazine and nightmares found among the hundreds of identified novel links between drugs and AEs (p < 0.05). The developed method can be used to extract dose-dependent ADR information from already collected EPR data. Large-scale AE extraction from EPRs may complement or even replace current drug safety monitoring methods in the future, reducing or eliminating manual reporting and enabling much faster ADR detection.
Multivessel system for cold-vapor mercury generation. Determination of mercury in hair and fish.
Boaventura, G R; Barbosa, A C; East, G A
1997-01-01
A multivessel system for the determination of mercury (Hg) by cold-vapor atomic absorption spectrometry (CV-AAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) was developed. The performance of the proposed device was tested by determining total Hg in quality-control samples of hair and fishes following acid digestion. Application of the apparatus to the determination of Hg by CV-AAS following alkaline digestion was studied as well. The detection limit obtained for CV-AAS was 0.11 ng/mL and for ICP-AES 1.39 ng/mL. The results show that the system is appropriate to be used in techniques involving cold-vapor generation of Hg.
Design and Test of Fan/Nacelle Models Quiet High-Speed Fan Design
NASA Technical Reports Server (NTRS)
Miller, Christopher J. (Technical Monitor); Repp, Russ; Gentile, David; Hanson, David; Chunduru, Srinivas
2003-01-01
The primary objective of the Quiet High-Speed Fan (QHSF) program was to develop an advanced high-speed fan design that will achieve a 6 dB reduction in overall fan noise over a baseline configuration while maintaining similar performance. The program applies and validates acoustic, aerodynamic, aeroelastic, and mechanical design tools developed by NASA, US industry, and academia. The successful fan design will be used in an AlliedSignal Engines (AE) advanced regional engine to be marketed in the year 2000 and beyond. This technology is needed to maintain US industry leadership in the regional turbofan engine market.
Development of acoustic emission evaluation method for repaired prestressed concrete bridge girders.
DOT National Transportation Integrated Search
2011-06-01
Acoustic emission (AE) monitoring has proven to be a useful nondestructive testing tool in ordinary reinforced concrete beams. Over the past decade, however, the technique has also been used to test other concrete structures. It has been seen that ac...
Measuring acoustic emissions in an avalanche slope
NASA Astrophysics Data System (ADS)
Reiweger, Ingrid; Schweizer, Jürg
2014-05-01
Measurements of acoustic emissions are a common technique for monitoring damage and predicting imminent failure of a material. Within natural hazards it has already been used to successfully predict the break-off of a hanging glacier. To explore the applicability of the acoustic emission (AE) technique for avalanche prediction, we installed two acoustic sensors (with 30 kHz and 60 kHz resonance frequency) in an avalanche prone slope at the Mittelgrat in the Parsenn ski area above Davos, Switzerland. The slope is north-east facing, frequently wind loaded, and approximately 35° steep. The AE signals - in particular the event energy and waiting time distributions - were compared with slope stability. The latter was determined by observing avalanche activity. The results of two winter's measurements yielded that the exponent β of the inverse cumulative distribution of event energy showed a significant drop (from a value of 3.5 to roughly 2.5) at very unstable conditions, i.e. on the three days during our measurement periods when spontaneous avalanches released on our study slope.
Choi, Young-Chul; Park, Jin-Ho; Choi, Kyoung-Sik
2011-01-01
In a nuclear power plant, a loose part monitoring system (LPMS) provides information on the location and the mass of a loosened or detached metal impacted onto the inner surface of the primary pressure boundary. Typically, accelerometers are mounted on the surface of a reactor vessel to localize the impact location caused by the impact of metallic substances on the reactor system. However, in some cases, the number of accelerometers is not sufficient to estimate the impact location precisely. In such a case, one of useful methods is to utilize other types of sensor that can measure the vibration of the reactor structure. For example, acoustic emission (AE) sensors are installed on the reactor structure to detect leakage or cracks on the primary pressure boundary. However, accelerometers and AE sensors have a different frequency range. The frequency of interest of AE sensors is higher than that of accelerometers. In this paper, we propose a method of impact source localization by using both accelerometer signals and AE signals, simultaneously. The main concept of impact location estimation is based on the arrival time difference of the impact stress wave between different sensor locations. However, it is difficult to find the arrival time difference between sensors, because the primary frequency ranges of accelerometers and AE sensors are different. To overcome the problem, we used phase delays of an envelope of impact signals. This is because the impact signals from the accelerometer and the AE sensor are similar in the whole shape (envelope). To verify the proposed method, we have performed experiments for a reactor mock-up model and a real nuclear power plant. The experimental results demonstrate that we can enhance the reliability and precision of the impact source localization. Therefore, if the proposed method is applied to a nuclear power plant, we can obtain the effect of additional installed sensors. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.
Montgomery, Stephen M; Kusel, Jeanette; Nicholas, Richard; Adlard, Nicholas
2017-09-01
Patients with relapsing-remitting multiple sclerosis (RRMS) treated with disease modifying therapies (DMTs) who continue to experience disease activity may be considered for escalation therapies such as fingolimod, or may be considered for alemtuzumab. Previous economic modeling used Markov models; applying one alternative technique, discrete event simulation (DES) modeling, allows re-treatment and long-term adverse events (AEs) to be included in the analysis. A DES was adapted to model relapse-triggered re-treatment with alemtuzumab and the effect of including ongoing quality-adjusted life year (QALY) decrements for AEs that extend beyond previous 1-year Markov cycles. As the price to the NHS of fingolimod in the UK is unknown, due to a confidential patient access scheme (PAS), a variety of possible discounts were tested. The interaction of re-treatment assumptions for alemtuzumab with the possible discounts for fingolimod was tested to determine which DMT resulted in lower lifetime costs. The lifetime QALY results were derived from modeled treatment effect and short- and long-term AEs. Most permutations of fingolimod PAS discount and alemtuzumab re-treatment rate resulted in fingolimod being less costly than alemtuzumab. As the percentage of patients who are re-treated with alemtuzumab due to experiencing a relapse approaches 100% of those who relapse whilst on treatment, the discount required for fingolimod to be less costly drops below 5%. Consideration of treatment effect alone found alemtuzumab generated 0.2 more QALYs/patient; the inclusion of AEs up to a duration of 1 year reduced this advantage to only 0.14 QALYs/patient. Modeling AEs with a lifetime QALY decrement found that both DMTs generated very similar QALYs with the difference only 0.04 QALYs/patient. When the model captured alemtuzumab re-treatment and long-term AE decrements, it was found that fingolimod is cost-effective compared to alemtuzumab, assuming application of only a modest level of confidential PAS discount.
2016-04-01
with Al top electrodes and Cu bottom electrodes. ................... 9 Figure 4. SPICE netlist structure...memory elements play a part in logic gate. 4.4.2 Simulation SPICE Simulation Program for Integrated Circuits Emphasis ( SPICE ) is a general-purpose...analog circuit simulator that was developed at the Electronics Research Laboratory of the University of California, Berkeley [6]. In 1975, SPICE
NASA Technical Reports Server (NTRS)
1998-01-01
This report presents a description of the tests performed, and the test data, for the A2 METSAT Signal Processor Assembly PN: 1331120-2, S/N F03. The assembly was tested in accordance with AE-26754, "METSAT Signal Processor Scan Drive Test and Integration Procedure."
NASA Technical Reports Server (NTRS)
1998-01-01
This report presents a description of the tests performed, and the test data, for the A2 METSAT Signal Processor Assembly PN: 1331120-2, S/N F04. The assembly was tested in accordance with AE-26754, "METSAT Signal Processor Scan Drive Test and Integration Procedure."
An Anticipatory Model of Cavitation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Allgood, G.O.; Dress, W.B., Jr.; Hylton, J.O.
1999-04-05
The Anticipatory System (AS) formalism developed by Robert Rosen provides some insight into the problem of embedding intelligent behavior in machines. AS emulates the anticipatory behavior of biological systems. AS bases its behavior on its expectations about the near future and those expectations are modified as the system gains experience. The expectation is based on an internal model that is drawn from an appeal to physical reality. To be adaptive, the model must be able to update itself. To be practical, the model must run faster than real-time. The need for a physical model and the requirement that the modelmore » execute at extreme speeds, has held back the application of AS to practical problems. Two recent advances make it possible to consider the use of AS for practical intelligent sensors. First, advances in transducer technology make it possible to obtain previously unavailable data from which a model can be derived. For example, acoustic emissions (AE) can be fed into a Bayesian system identifier that enables the separation of a weak characterizing signal, such as the signature of pump cavitation precursors, from a strong masking signal, such as a pump vibration feature. The second advance is the development of extremely fast, but inexpensive, digital signal processing hardware on which it is possible to run an adaptive Bayesian-derived model faster than real-time. This paper reports the investigation of an AS using a model of cavitation based on hydrodynamic principles and Bayesian analysis of data from high-performance AE sensors.« less
Kamala C T; Balaram V; Dharmendra V; Satyanarayanan M; Subramanyam K S V; Krishnaiah A
2014-11-01
Recently introduced microwave plasma-atomic emission spectroscopy (MP-AES) represents yet another and very important addition to the existing array of modern instrumental analytical techniques. In this study, an attempt is made to summarize the performance characteristics of MP-AES and its potential as an analytical tool for environmental studies with some practical examples from Patancheru and Uppal industrial sectors of Hyderabad city. A range of soil, sediment, water reference materials, particulate matter, and real-life samples were chosen to evaluate the performance of this new analytical technique. Analytical wavelengths were selected considering the interference effects of other concomitant elements present in different sample solutions. The detection limits for several elements were found to be in the range from 0.05 to 5 ng/g. The trace metals analyzed in both the sectors followed the topography with more pollution in the low-lying sites. The metal contents were found to be more in ground waters than surface waters. Since a decade, the pollutants are transfered from Patancheru industrial area to Musi River. After polluting Nakkavagu and turning huge tracts of agricultural lands barren besides making people residing along the rivulet impotent and sick, industrialists of Patancheru are shifting the effluents to downstream of Musi River through an 18-km pipeline from Patancheru. Since the effluent undergoes primary treatment at Common Effluent Treatment Plant (CETP) at Patanchru and travels through pipeline and mixes with sewage, the organic effluents will be diluted. But the inorganic pollutants such as heavy and toxic metals tend to accumulate in the environmental segments near and downstreams of Musi River. The data generated by MP-AES of toxic metals like Zn, Cu, and Cr in the ground and surface waters can only be attributed to pollution from Patancheru since no other sources are available to Musi River.
Microseismic Monitoring of the Olivine → Spinel Transition in Fayalite Under Non-Hydrostatic Stress
NASA Astrophysics Data System (ADS)
Officer, T.; Secco, R. A.
2016-12-01
In subduction zones, deep earthquakes are thought to be associated with faulting that arises from phase transformations. In order to test the viability of this mechanism experimentally, it is necessary to make microseismic measurements while the mineral under investigation is subjected to the pressure and temperature (P,T) environment at depth. A system has been developed capable of making in situ acoustic emission (AE) measurements on samples under P,T conditions representative of the upper mantle and transition zone. Experiments are performed in a 3000-ton multi-anvil press using an 18/11 octahedral cell with 6 piezoelectric transducers mounted on the rear side of the anvils. AE signals are collected at a sampling rate of 40 MHz using a triggered system and a data buffer for continuous recording so full waveforms of AE events are captured. The use of multiple transducers distributed in a microseismic array allows for events to be located within the sample through automatic arrival time picking and least squares inversion techniques. The multi-anvil apparatus constitutes an inherently noisy environment both acoustically and electrically, therefore methods of noise reduction were developed and will be discussed. This technique has been used to measure acoustic signals generated from the fracturing of quartz beads during high pressure deformation and to investigate the possibility that the phase transformation from olivine to spinel, known to occur in subduction zones, is associated with deep-focus earthquakes (300 - 690 km depth). The analog material fayalite (Fe2SiO4), the iron end member of olivine, has been examined. Information about its synthesis and sintering will be discussed as well as results of AE experiments on samples experiencing deviatoric stress under high pressure (P = 4-9 GPa) and high temperature (T = 773-1273 K) conditions in the spinel stability field.
Kogan, Pablo; Arenas, Jorge P; Bermejo, Fernando; Hinalaf, María; Turra, Bruno
2018-06-13
Urban soundscapes are dynamic and complex multivariable environmental systems. Soundscapes can be organized into three main entities containing the multiple variables: Experienced Environment (EE), Acoustic Environment (AE), and Extra-Acoustic Environment (XE). This work applies a multidimensional and synchronic data-collecting methodology at eight urban environments in the city of Córdoba, Argentina. The EE was assessed by means of surveys, the AE by acoustic measurements and audio recordings, and the XE by photos, video, and complementary sources. In total, 39 measurement locations were considered, where data corresponding to 61 AE and 203 EE were collected. Multivariate analysis and GIS techniques were used for data processing. The types of sound sources perceived, and their extents make up part of the collected variables that belong to the EE, i.e. traffic, people, natural sounds, and others. Sources explaining most of the variance were traffic noise and natural sounds. Thus, a Green Soundscape Index (GSI) is defined here as the ratio of the perceived extents of natural sounds to traffic noise. Collected data were divided into three ranges according to GSI value: 1) perceptual predominance of traffic noise, 2) balanced perception, and 3) perceptual predominance of natural sounds. For each group, three additional variables from the EE and three from the AE were applied, which reported significant differences, especially between ranges 1 and 2 with 3. These results confirm the key role of perceiving natural sounds in a town environment and also support the proposal of a GSI as a valuable indicator to classify urban soundscapes. In addition, the collected GSI-related data significantly helps to assess the overall soundscape. It is noted that this proposed simple perceptual index not only allows one to assess and classify urban soundscapes but also contributes greatly toward a technique for separating environmental sound sources. Copyright © 2018 Elsevier B.V. All rights reserved.
Efficacy and safety of ipilimumab 3mg/kg in patients with pretreated, metastatic, mucosal melanoma.
Del Vecchio, Michele; Di Guardo, Lorenza; Ascierto, Paolo A; Grimaldi, Antonio M; Sileni, Vanna Chiarion; Pigozzo, Jacopo; Ferraresi, Virginia; Nuzzo, Carmen; Rinaldi, Gaetana; Testori, Alessandro; Ferrucci, Pier F; Marchetti, Paolo; De Galitiis, Federica; Queirolo, Paola; Tornari, Elena; Marconcini, Riccardo; Calabrò, Luana; Maio, Michele
2014-01-01
Mucosal melanoma is an extremely rare and aggressive malignancy that often remains undetected until it reaches an advanced stage, when effective treatment options are limited. The activity and safety of ipilimumab were assessed in an Expanded Access Programme (EAP) that included patients with metastatic, mucosal melanoma. Ipilimumab was available upon physician request for patients aged ⩾16years with stage III (unresectable) or IV skin, ocular or mucosal melanoma, who had failed or did not tolerate previous treatments and had no other therapeutic option available. Patients received ipilimumab 3mg/kg every 3weeks for four doses. Patients with stable disease or an objective response to ipilimumab were eligible for retreatment upon disease progression. Tumour assessments were conducted at baseline and week 12 using immune-related response criteria. Patients were monitored for adverse events (AEs), including immune-related AEs, within 3 to 4days of each scheduled visit. Of 855 patients participating in the EAP in Italy, 71 (8%) had metastatic, mucosal melanoma. With a median follow-up of 21.8months, the response rate was 12% and the immune-related disease control rate was 36%. Median progression-free survival and overall survival were 4.3 and 6.4months, respectively. In total, 34% of patients reported treatment-related AEs of any grade, which were grade 3 or 4 in 9% of patients. AEs were generally manageable as per protocol-specific guidelines. Ipilimumab may be a feasible treatment option in pretreated patients with metastatic mucosal melanoma, and warrants further investigation in prospective clinical trials. Copyright © 2013 Elsevier Ltd. All rights reserved.
Karagöz, Alper; Acar, Sümeyra; Körkoca, Hanifi
2015-01-01
The purpose of the study was to evaluate the performance of the VITEK mass spectrometry (MS) (bioMérieux, France) system for the identification of Klebsiella spp. isolated from different sources. Moreover, while assessing the ability of the VITEK 2 automated expert system (AES) to recognize antimicrobial resistance patterns, the researchers have extended the study to compare VITEK 2 with the routine antimicrobial susceptibility testing method. This study tested 51 Klebsiella spp. isolates that were isolated from environmental examples and clinical examples. Results of conventional methods and the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS were compared. Then, any differing results were compared against a reference 16S rRNA gene sequence, and when indicated, a recA sequencing analysis was done. VITEK MS correctly identified 100% of the Klebsiella spp. isolates. There were two K. oxytoca isolates incorrectly identified to the species level with conventional methods according to the 16S rRNA gene sequencing analysis. In addition, a VITEK 2 AST-N261 card was used for the detection of extended spectrum beta-lactamases (ESBL). Using the VITEK 2 AES, ESBL positivity was found at the rate of 16.3% whereas this rate was 4.08% using the disk diffusion method. MALDI-TOF MS is a rapid and accurate method for the identification of Klebsiella spp. Moreover, the bioMérieux AES provides a useful laboratory tool for the interpretation of susceptibility results.
Yao, Shuyang; Zhi, Xiuyi; Wang, Ruotian; Qian, Kun; Hu, Mu; Zhang, Yi
2016-09-01
Epidermal growth factor receptor (EGFR) mutations occur in about 50% of Asian patients with non-small cell lung cancer (NSCLC). Patients with advanced NSCLC and EGFR mutations derive clinical benefit from treatment with EGFR-tyrosine kinase inhibitors (TKIs). This study assessed the efficacy and safety of adjuvant icotinib without chemotherapy in EGFR-mutated NSCLC patients undergoing resection of stage IB-IIIA. Our retrospective study enrolled 20 patients treated with icotinib as adjuvant therapy. Survival factors were evaluated by univariate and Cox regression analysis. The median follow-up time was 30 months (range 24-41). At the data cut-off, five patients (25%) had recurrence or metastasis and one patient had died of the disease. The two-year disease-free survival (DFS) rate was 85%. No recurrence occurred in the high-risk stage IB subgroup during the follow-up period. In univariate analysis, the micropapillary pattern had a statistically significant effect on DFS ( P = 0.040). Multivariate logistic regression analysis showed that there was no independent predictor. Drug related adverse events (AEs) occurred in nine patients (45.0%). The most common AEs were skin-related events and diarrhea, but were relatively mild. No grade 3 AEs or occurrences of intolerable toxicity were observed. Icotinib as adjuvant therapy is effective in patients harboring EGFR mutations after complete resection, with an acceptable AE profile. Further trials with larger sample sizes might confirm the efficiency of adjuvant TKI in selected patients. © 2016 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.
Bang, Yung-Jue; Takano, Toshimi; Lin, Chia-Chi; Fasanmade, Adedigbo; Yang, Huyuan; Danaee, Hadi; Asato, Takayuki; Kalebic, Thea; Wang, Hui; Doi, Toshihiko
2018-01-01
Purpose This phase 1 dose-escalation portion of the study evaluated the safety, pharmacokinetics (PK), and antitumor activity of TAK-264 in Asian patients with advanced gastrointestinal (GI) carcinoma or metastatic or recurrent gastric or gastroesophageal junction adenocarcinoma expressing guanylyl cyclase C (GCC). Materials and Methods Adult patients with advanced GI malignancies expressing GCC (H-score ≥ 10) received TAK-264 on day 1 of 3-week cycles as 30-minute intravenous infusions for up to 1 year or until disease progression or unacceptable toxicity. The primary objectives were to evaluate the safety profile including dose-limiting toxicities (DLTs) during cycle 1, determine the maximum tolerated dose (MTD), and characterize the PK profile of TAK-264. Results Twelve patients were enrolled and treated with 1.2 mg/kg (n=3), 1.5 mg/kg (n=3), or 1.8 mg/kg TAK-264 (n=6). Median number of treatment cycles received was two (range, 1 to 10). None of the patients experienced a DLT and the MTD was not determined. Ten patients (83%) experienced adverse events (AEs). The most common were neutropenia, anorexia, and nausea (each reported by four patients). Five patients (42%) experienced grade ≥ 3 AEs consisting of tumor hemorrhage and hypertension, ascites, adrenal insufficiency, neutropenia and asthenia. Serum exposure to TAK-264 increased proportionally with the dose and the median half-life was approximately 5.5-6.6 days. No patients experienced an objective response. Conclusion TAK-264 demonstrated a manageable safety profile with limited antitumor activity consistent with studies conducted in Western patients with advanced GI malignancies. TAK-264 exposure increased proportionally with the dose. PMID:28494535
Reichardt, Peter; Kang, Yoon-Koo; Rutkowski, Piotr; Schuette, Jochen; Rosen, Lee S; Seddon, Beatrice; Yalcin, Suayib; Gelderblom, Hans; Williams, Charles C; Fumagalli, Elena; Biasco, Guido; Hurwitz, Herbert I; Kaiser, Pamela E; Fly, Kolette; Matczak, Ewa; Chen, Liang; Lechuga, Maria José; Demetri, George D
2015-01-01
BACKGROUND To provide sunitinib to patients with gastrointestinal stromal tumor (GIST) who were otherwise unable to obtain sunitinib; to obtain broad safety and efficacy data from a large population of patients with advanced GIST after imatinib failure. METHODS Imatinib-resistant/intolerant patients with advanced GIST received sunitinib on an initial dosing schedule (IDS) of 50 mg/day in 6-week cycles (4 weeks on treatment, 2 weeks off). Tumor assessment frequency was per local practice, with response assessed by investigators per Response Evaluation Criteria in Solid Tumors version 1.0. Overall survival (OS) and safety were assessed regularly. Post-hoc analyses evaluated different patterns of treatment management. RESULTS At final data cutoff, 1124 patients comprised the intent-to-treat population; 15% had a baseline Eastern Cooperative Oncology Group performance status ≥2. Median treatment duration was 7.0 months. Median time to tumor progression was 8.3 months (95% confidence interval [CI], 8.0–9.4), and median OS was 16.6 months (95% CI, 14.9–18.0) with 36% of patients alive at the time of analysis. Patients in whom the IDS was modified exhibited longer median OS (23.5 months) than those treated strictly per the IDS (11.1 months). The most common treatment-related grade 3/4 adverse events (AEs) were hand-foot syndrome (11%), fatigue (9%), neutropenia (8%), hypertension (7%), and thrombocytopenia (6%). Treatment-related AEs associated with cardiac function (eg, congestive heart failure and myocardial infarction) were reported at frequencies of ≤1% each. CONCLUSIONS This treatment-use study confirms the long-term safety and efficacy of sunitinib in a large international population of patients with advanced GIST after imatinib failure. PMID:25641662
Kerr, Zachary Y; Dalton, Sara L; Roos, Karen G; Djoko, Aristarque; Phelps, Jennifer; Dompier, Thomas P
2016-05-01
In Indiana, high school football coaches are required to complete a coaching education course with material related to concussion awareness, equipment fitting, heat emergency preparedness, and proper technique. Some high schools have also opted to implement a player safety coach (PSC). The PSC, an integral component of USA Football's Heads Up Football (HUF) program, is a coach whose primary responsibility is to ensure that other coaches are implementing proper tackling and blocking techniques alongside other components of the HUF program. To compare injury rates in Indiana high school football teams by their usage of a PSC or online coaching education only. Cohort study; Level of evidence, 2. Athletic trainers (ATs) evaluated and tracked injuries at each practice and game during the 2015 high school football season. Players were drawn from 6 teams in Indiana. The PSC group, which used the PSC component, was comprised of 204 players from 3 teams. The "education only" group (EDU), which utilized coaching education only, was composed of 186 players from 3 teams. Injury rates and injury rate ratios (IRRs) were reported with 95% confidence intervals (CIs). During 25,938 athlete-exposures (AEs), a total of 149 injuries were reported, of which 54 (36.2%) and 95 (63.8%) originated from the PSC and EDU groups, respectively. The practice injury rate was lower in the PSC group than the EDU group (2.99 vs 4.83/1000 AEs; IRR, 0.62; 95% CI, 0.40-0.95). The game injury rate was also lower in the PSC group than the EDU group (11.37 vs 26.37/1000 AEs; IRR, 0.43; 95% CI, 0.25-0.74). When restricted to concussions only, the rate was lower in the PSC group (0.09 vs 0.73/1000 AEs; IRR, 0.12; 95% CI, 0.01-0.94), although only 1 concussion was reported in the PSC group. No differences were found in game concussion rates (0.60 vs 4.39/1000 AEs; IRR, 0.14; 95% CI, 0.02-1.11). Findings support the PSC as an effective method of injury mitigation in high school football. Future research should seek to replicate this study using larger samples from additional states.
Kerr, Zachary Y.; Dalton, Sara L.; Roos, Karen G.; Djoko, Aristarque; Phelps, Jennifer; Dompier, Thomas P.
2016-01-01
Background: In Indiana, high school football coaches are required to complete a coaching education course with material related to concussion awareness, equipment fitting, heat emergency preparedness, and proper technique. Some high schools have also opted to implement a player safety coach (PSC). The PSC, an integral component of USA Football’s Heads Up Football (HUF) program, is a coach whose primary responsibility is to ensure that other coaches are implementing proper tackling and blocking techniques alongside other components of the HUF program. Purpose: To compare injury rates in Indiana high school football teams by their usage of a PSC or online coaching education only. Study Design: Cohort study; Level of evidence, 2. Methods: Athletic trainers (ATs) evaluated and tracked injuries at each practice and game during the 2015 high school football season. Players were drawn from 6 teams in Indiana. The PSC group, which used the PSC component, was comprised of 204 players from 3 teams. The “education only” group (EDU), which utilized coaching education only, was composed of 186 players from 3 teams. Injury rates and injury rate ratios (IRRs) were reported with 95% confidence intervals (CIs). Results: During 25,938 athlete-exposures (AEs), a total of 149 injuries were reported, of which 54 (36.2%) and 95 (63.8%) originated from the PSC and EDU groups, respectively. The practice injury rate was lower in the PSC group than the EDU group (2.99 vs 4.83/1000 AEs; IRR, 0.62; 95% CI, 0.40-0.95). The game injury rate was also lower in the PSC group than the EDU group (11.37 vs 26.37/1000 AEs; IRR, 0.43; 95% CI, 0.25-0.74). When restricted to concussions only, the rate was lower in the PSC group (0.09 vs 0.73/1000 AEs; IRR, 0.12; 95% CI, 0.01-0.94), although only 1 concussion was reported in the PSC group. No differences were found in game concussion rates (0.60 vs 4.39/1000 AEs; IRR, 0.14; 95% CI, 0.02-1.11). Conclusion: Findings support the PSC as an effective method of injury mitigation in high school football. Future research should seek to replicate this study using larger samples from additional states. PMID:27275000
Evaluation of damage in reinforced concrete bridge beams using acoustic emission technique
NASA Astrophysics Data System (ADS)
Vidya Sagar, R.; Raghu Prasad, B. K.; Sharma, Reema
2012-06-01
Acoustic emission (AE) testing is a well-known method for damage identification of various concrete structures including bridges. This article presents a method to assess damage in reinforced concrete (RC) bridge beams subjected to incremental cyclic loading. The specifications in the standard NDIS-2421 were used to classify the damage in RC bridge beams. Earlier researchers classified the damage occurring in bridge beams by using crack mouth opening displacement (CMOD) and AE released and proposed a standard (NDIS-2421: the Japanese Society for NonDestructive Inspection). In general, multiple cracks take place in RC beams under bending; therefore, utilisation of CMOD for crack detection may not be appropriate. In the present study, the damage in RC beams is classified by using the AE released, deflection, strains in steel and concrete, because the measurement of the strains in steel and concrete is easy and the codes of practice are specified for different limit states (IS-456:2000). The observations made in the present experimental study have some important practical applications in assessing the state of damage of concrete structural members.
Jay, R
1996-07-01
This paper is an account of a qualitative study of significantly injured patients' experience in the Accident and Emergency department (A&E) and explores the question 'What A&E nursing interventions are effective in providing reassurance and reducing anxiety in patients with significant trauma?' A review of the limited literature available indicates that when a seriously injured patient is admitted to the A&E department, the medical and nursing staff often respond urgently to the physiological crisis without adequate consideration of psychological needs. The research design used a version of the Critical Incident Technique to interview 7 patients who had sustained serious injuries a few days previously. The findings indicate that central to the delivery of emergency care is the individual's transition from their normal independent existence through pre-hospital trauma and into the isolating experience of fear, dependence and the resuscitation room. Different methods of coping were required to meet their needs and regain some control. Methods such as touch, company and information became paramount as did the need to trust the people seen to be in control of their new environment.
NASA Technical Reports Server (NTRS)
Shokr, Mohammed; Markus, Thorsten
2006-01-01
Ice concentration retrieved from spaceborne passive-microwave observations is a prime input to operational sea-ice-monitoring programs, numerical weather prediction models, and global climate models. Atmospheric Environment Service (AES)- York and the Enhanced National Aeronautics and Space Administration Team (NT2) are two algorithms that calculate ice concentration from Special Sensor Microwave/Imager observations. This paper furnishes a comparison between ice concentrations (total, thin, and thick types) output from NT2 and AES-York algorithms against the corresponding estimates from the operational analysis of Radarsat images in the Canadian Ice Service (CIS). A new data fusion technique, which incorporates the actual sensor's footprint, was developed to facilitate this study. Results have shown that the NT2 and AES-York algorithms underestimate total ice concentration by 18.35% and 9.66% concentration counts on average, with 16.8% and 15.35% standard deviation, respectively. However, the retrieved concentrations of thin and thick ice are in much more discrepancy with the operational CIS estimates when either one of these two types dominates the viewing area. This is more likely to occur when the total ice concentration approaches 100%. If thin and thick ice types coexist in comparable concentrations, the algorithms' estimates agree with CIS'S estimates. In terms of ice concentration retrieval, thin ice is more problematic than thick ice. The concept of using a single tie point to represent a thin ice surface is not realistic and provides the largest error source for retrieval accuracy. While AES-York provides total ice concentration in slightly more agreement with CIS'S estimates, NT2 provides better agreement in retrieving thin and thick ice concentrations.
Wang, Meiling; Wu, Hongqi; Xu, Jing; Li, Chunlian; Wang, Yong; Wang, Zhonghua
2017-01-01
The diploid Aegilops tauschii is the D-genome donor to hexaploid wheat (Triticum aestivum) and represents a potential source for genetic study in common wheat. The ubiquitous wax covering the aerial parts of plants plays an important role in protecting plants against non-stomatal water loss. Cuticular waxes are complex mixtures of very-long-chain fatty acids, alkanes, primary and/or secondary alcohols, aldehydes, ketones, esters, triterpenes, sterols, and flavonoids. In the present work, primary alcohols were identified as the major components of leaf cuticular wax in Ae. tauschii, with C26:0-OH being the dominant primary alcohol. Analysis by scanning electron microscope revealed that dense platelet-shaped wax crystals were deposited on leaf surfaces of Ae. tauschii. Ten putative wax biosynthetic genes encoding fatty acyl-coenzyme A reductase (FAR) were identified in the genome of Ae. tauschii. Five of these genes, Ae.tFAR1, Ae.tFAR2, Ae.tFAR3, Ae.tFAR4, and Ae.tFAR6, were found expressed in the leaf blades. Heterologous expression of the five Ae.tFARs in yeast (Saccharomyces cerevisiae) showed that Ae.tFAR1, Ae.tFAR2, Ae.tFAR3, Ae.tFAR4, and Ae.tFAR6 were predominantly responsible for the accumulation of C16:0, C18:0, C26:0, C24:0, and C28:0 primary alcohols, respectively. In addition, nine Ae.tFAR paralogous genes were located on D chromosome of wheat and the wheat nullisomic–tetrasomic lines with the loss of Ae.tFAR3 and Ae.tFAR4 paralogous genes had significantly reduced levels of primary alcohols in the leaf blades. Collectively, these data suggest that Ae.tFAR1, Ae.tFAR2, Ae.tFAR3, Ae.tFAR4, and Ae.tFAR6 encode alcohol-forming FARs involved in the biosynthesis of primary alcohols in the leaf blades of Ae. tauschii. The information obtained in Ae. tauschii enables us to better understand wax biosynthesis in common wheat. PMID:28659955
Goriunova, S V; Kochieva, E Z; Chikida, N N; Pukhal'skiĭ, V A
2004-05-01
RAPD analysis was carried out to study the genetic variation and phylogenetic relationships of polyploid Aegilops species, which contain the D genome as a component of the alloploid genome, and diploid Aegilops tauschii, which is a putative donor of the D genome for common wheat. In total, 74 accessions of six D-genome Aegilops species were examined. The highest intraspecific variation (0.03-0.21) was observed for Ae. tauschii. Intraspecific distances between accessions ranged 0.007-0.067 in Ae. cylindrica, 0.017-0.047 in Ae. vavilovii, and 0.00-0.053 in Ae. juvenalis. Likewise, Ae. ventricosa and Ae. crassa showed low intraspecific polymorphism. The among-accession difference in alloploid Ae. ventricosa (genome DvNv) was similar to that of one parental species, Ae. uniaristata (N), and substantially lower than in the other parent, Ae. tauschii (D). The among-accession difference in Ae. cylindrica (CcDc) was considerably lower than in either parent, Ae. tauschii (D) or Ae. caudata (C). With the exception of Ae. cylindrica, all D-genome species--Ae. tauschii (D), Ae. ventricosa (DvNv), Ae. crassa (XcrDcrl and XcrDcrlDcr2), Ae. juvenalis (XjDjUj), and Ae. vavilovii (XvaDvaSva)--formed a single polymorphic cluster, which was distinct from clusters of other species. The only exception, Ae. cylindrica, did not group with the other D-genome species, but clustered with Ae. caudata (C), a donor of the C genome. The cluster of these two species was clearly distinct from the cluster of the other D-genome species and close to a cluster of Ae. umbellulata (genome U) and Ae. ovata (genome UgMg). Thus, RAPD analysis for the first time was used to estimate and to compare the interpopulation polymorphism and to establish the phylogenetic relationships of all diploid and alloploid D-genome Aegilops species.
File Cryptography with AES and RSA for Mobile Based on Android
NASA Astrophysics Data System (ADS)
laia, Yonata; Nababan, Marlince; Sihombing, Oloan; Aisyah, Siti; Sitanggang, Delima; Parsaoran, Saut; Zendato, Niskarto
2018-04-01
The users of mobile based on android were increasing currently even now mobile was almost the same computer one of which could be used to be done by every users mobile was save the individual important data.Saving the data on mobile was very risk because become hackers’ target. That was the reason of researchers want to add cryptography which the combination between Advance Encryption System (AES) dan Ron Rivest, Adi Shamir dan Len Adleman (RSA). The result of the second method above could do cryptography data on mobile. With different encryption time where the file size; 25.44 KB, encryption time 4 second, 200 KB, 5 second, 600 KB 7 second, 2.29 MB, 10 second. Where decryption 25.44 KB, encryption 2 second, 200 KB, 1.5 second, 600 KB 2.5 second, 2.29 MB, 2.7 second.
NPS alternate techsat satellite, design project for AE-4871
NASA Technical Reports Server (NTRS)
1993-01-01
This project was completed as part of AE-4871, Advanced Spacecraft Design. The intent of the course is to provide experience in the design of all the major components in a spacecraft system. Team members were given responsibility for the design of one of the six primary subsystems: power, structures, propulsion, attitude control, telemetry, tracking and control (TT&C), and thermal control. In addition, a single member worked on configuration control, launch vehicle integration, and a spacecraft test plan. Given an eleven week time constraint, a preliminary design of each subsystem was completed. Where possible, possible component selections were also made. Assistance for this project came principally from the Naval Research Laboratory's Spacecraft Technology Branch. Specific information on components was solicited from representatives in industry. The design project centers on a general purpose satellite bus that is currently being sought by the Strategic Defense Initiative.
2012-07-27
CAPE CANAVERAL, Fla. - NASA's Morpheus lander, a vertical test bed vehicle, is unloaded at a building at the Shuttle Landing Facility, or SLF, at the Kennedy Space Center in Florida. Morpheus is designed to demonstrate new green propellant propulsion systems and autonomous landing and an Autonomous Landing and Hazard Avoidance Technology, or ALHAT, system. Checkout of the prototype lander has been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free flight. The SLF site will provide the lander with the kind of field necessary for realistic testing. Project Morpheus is one of 20 small projects comprising the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. For more information on Project Morpheus, visit http://www.nasa.gov/centers/johnson/exploration/morpheus/index.html Photo credit: NASA/ Charisse Nahser
2012-07-27
CAPE CANAVERAL, Fla. - A forklift is used at the Kennedy Space Center in Florida to unload NASA's Morpheus lander, a vertical test bed vehicle. Morpheus is designed to demonstrate new green propellant propulsion systems and autonomous landing and an Autonomous Landing and Hazard Avoidance Technology, or ALHAT, system. Checkout of the prototype lander has been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free flight. The SLF site will provide the lander with the kind of field necessary for realistic testing. Project Morpheus is one of 20 small projects comprising the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. For more information on Project Morpheus, visit http://www.nasa.gov/centers/johnson/exploration/morpheus/index.html Photo credit: NASA/ Charisse Nahser