WorldWideScience

Sample records for base mismatch detection

  1. Detection of base pair mismatches in duplex DNA and RNA oligonucleotides using electrospray mass spectrometry

    Science.gov (United States)

    Griffey, Richard H.; Greig, Michael J.

    1997-05-01

    The identify and location of base pair mismatches in non- covalent DNA:RNA duplexes are established using MS and MS-MS on a quadruple ion trap with electrospray ionization (ESI). MS-MS experiments on a 14mer duplex (D) with a single C:A base pair mismatch using lower activation energy results in selective cleavage of the mismatched A nucleobase, even in the presence of the wild-type duplex. The location of the mismatch base pair can be discerned via presence of the wild-type duplex. The location of the mismatch base pair can be discerned via selection of the (D-5H)5- ion and fragmentation of the backbone at that location in a n additional MS-MS experiment. Selective fragmentation is observed for C in a C-C mismatched base pair, which is very difficult to detect using chemical cleavage or E. coli mismatch binding protein. In an RNA:DNA duplex with a single base pair mismatch, the DNA base is removed without fragmentation of the RNA strand, greatly simplifying the interpretation of the resulting MS spectrum. A method is presented for detecting two DNA strands, for example a point mutation which generates an oncogenic phenotype, and the wild-type message. The results suggest that ESI-MS-MS may provide a rapid and selective method to identify and locate genetic mutations without the need for chemical degradation or protein binding followed by gel electrophoresis.

  2. DNA biosensor based on hybridization refractory mutation system approach for single mismatch detection.

    Science.gov (United States)

    Joda, Hamdi; Beni, Valerio; Katakis, Ioanis; O'Sullivan, Ciara K

    2015-04-01

    We report on a simple approach to enhance solid-phase hybridization-based single base mismatch discrimination at high ionic strength based on the deliberate insertion of a natural DNA base mismatch in the surface-tethered probe. A large drop in hybridization signal of single base mismatched alleles using the designed probe as compared with the conventional probe, from 80% to less than 25% of the signal obtained with the fully complementary, non-mutation-containing sequence, when using colorimetric detection was further improved to 20% when using electrochemical detection, attributable to a difference of spacing of immobilized probes. Finally, the designed probe was used for the electrochemical detection of the DQA1*05:05 allele amplified from real human blood samples. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Gold-based optical biosensor for single-mismatched DNA detection using salt-induced hybridization

    DEFF Research Database (Denmark)

    Zhan, Zongrui; Ma, Xingyi; Cao, Cuong

    2011-01-01

    In this study, a gold nanoparticle (Au-NP)-based detection method for sensitive and specific DNA-based diagnostic applications is described. A sandwich format consisting of Au-NPs/DNA/PMP (Streptavidin-coated MagnetSphere Para-Magnetic Particles) was fabricated. PMPs captured and separated target...... DNA while Au-NPs modified with oligonucleotide detection sequences played a role in recognition and signal production. Due to the much lower stability of mismatched DNA strands caused by unstable duplex structures in solutions of relatively low salt concentration, hybridization efficiency...... in the presence of different buffers was well investigated, and thus, the optimized salt concentration allowed for discrimination of single-mismatched DNA (MMT) from perfectly matched DNA (PMT). Therefore, quantitative information concerning the target analyte was translated into a colorimetric signal, which...

  4. Backward masking and visual mismatch negativity: electrophysiological evidence for memory-based detection of deviant stimuli.

    Science.gov (United States)

    Czigler, István; Weisz, Júlia; Winkler, István

    2007-07-01

    Sequences composed of two different colored checkerboard patterns (standard and deviant) were presented to adults. Each pattern was followed by a mask with stimulus onset asynchronies (SOAs) varying between 14 and 174 ms. ERPs were recorded to the deviant and standard stimuli while the participants detected changes of a cross, which was continuously present at the center of the screen. In further experiments, the participants performed a Go-NoGo task detecting the deviant checkerboards. Deviant stimuli elicited an occipital negative component with 124-132 ms mean latency (the visual mismatch negativity, vMMN) at test (standard or deviant)-to-mask SOAs longer than 27 ms. No vMMN amplitude increase was observed beyond 40 ms test-to-mask intervals, whereas detection of deviant checkerboard patterns improved up to 174-ms SOA. Therefore the processes underlying vMMN elicitation cannot fully explain the overt detection of visual deviance.

  5. Trifunctional fluorescent unnatural nucleoside: Label free detection of T-T/C-C base mismatches, abasic site and bulge DNA.

    Science.gov (United States)

    Bag, Subhendu Sekhar; Pradhan, Manoj Kumar; Talukdar, Sangita

    2017-08-01

    The detection and targeting of both the mismatched and abasic DNA is highly important which would ultimately help in designing new diagnostics and chemotherapeutics. Furthermore, sensing and targeting the bulge sequence with a fluorescent probe would be useful to study the role of bulges in nucleic acid function or could have significant therapeutic potential. Thus, detection of specific bulges by small fluorescent molecules is an attractive research area since the past several years. Many attempts have been made to prepare such compounds. We report herein a label free strategy for the detection of pyrimidine base mismatches (T/T and C/C), sensing of abasic site, and pyrimidine base bulge DNA using an unnatural tetrazolylpyrene nucleoside ( TPy B Do ) as a bare fluorescent probe. The H-bonding/hydrophobic force mediated interactions allow the sensing of all three deformed DNA via an enhancement of fluorescence signal using our simple "Just-Mix and Read" strategy. The binding of the probe to all the three deformed DNA duplexes is accompanied by an increase in the thermal melting stability of the deformed DNAs. That the probe binds efficiently to the minor groove near the deformed site was evident from spectroscopic studies. All the spectral evidences open up a multitude of possibilities for using our probe, tetrazolylpyrene nucleoside, as an efficient fluorescent light-up bio-probe for label free DNA detection. Copyright © 2017. Published by Elsevier B.V.

  6. A Novel Electrochemical Sensor Based on [Ru(NH3)6]Cl3 as a Redox Indicator for the Detection of G-G Mismatched DNA.

    Science.gov (United States)

    Zhu, Xiaoqian; Huang, Min; Li, Jiao; He, Hanping; Zhang, Xiuhua; Wang, Shengfu

    2017-01-01

    In this paper, a novel electrochemical sensor was developed for the rapid detection of G-G mismatched DNA based on hexaammineruthenium(III) chloride ([Ru(NH 3 ) 6 ]Cl 3 ) as a redox indicator. The sensor platform was constructed by immobilizing small molecules (NC-linker) on the gold electrode via amide bonds. The as-prepared NC-linker as the nucleic acids recognition molecule can interact with the G base of DNA. After the sensor was incubated with G-G mismatched DNA, the double-stranded DNA (dsDNA) acted as carriers of the signal tags-[Ru(NH 3 ) 6 ]Cl 3 , which resulted in a remarkable electrochemical signal. More binding of [Ru(NH 3 ) 6 ]Cl 3 led to increases of the electrochemical signal. Other mismatched DNA produced only a low response, as well as complementary DNA. Thus G-G mismatched DNA can be easily discriminated from other mismatched and complementary DNA based on the sensor. Furthermore, the method was simple, rapid and repeatable for the detection of G-G mismatched DNA. The selective detection of target dsDNA was achieved by a relative current ratio of the target and control DNA. These results demonstrated that this strategy could provide great promise for the rapid and specific detection of other sequence-specific DNA.

  7. Preattentive visual change detection as reflected by the mismatch negativity (MMN)--evidence for a memory-based process.

    Science.gov (United States)

    Maekawa, Toshihiko; Tobimatsu, Shozo; Ogata, Katsuya; Onitsuka, Toshiaki; Kanba, Shigenobu

    2009-09-01

    The aim of this study was to test the hypothesis that visual mismatch negativity (vMMN) is based on memory trace formation. Special care was taken to distinguish between memory mismatch and rareness effect. Subjects were seated in front of a monitor and asked to listen to a story. The standard sequence block consisted of nine consecutive 24-vane windmill patterns with an 800-ms inter-stimulus interval. The deviant sequence block consisted of one 24-vane pattern with eight six-vane patterns. Inter-train intervals (ITIs) varied among 1, 6, and 12s in the changing ITI experiment, while the deviant stimulus occupied the eighth position in the sequence. In the changing order experiment, the position of the deviant stimulus was varied among the second, fourth and eighth position with a 12-s constant ITI. vMMN was ascertained from the difference in responses to standard and deviant stimulus. vMMN appeared in the occipital region 150-300 ms after stimulus onset. It was significantly modulated by the ITI, and more than four preceding stimuli were needed to reinstate the implicit memory trace. These results suggest that memory-based change detection underlies vMMN. Therefore, vMMN is useful to study visual sensory memory function.

  8. Advanced radar detection schemes under mismatched signal models

    CERN Document Server

    Bandiera, Francesco

    2009-01-01

    Adaptive detection of signals embedded in correlated Gaussian noise has been an active field of research in the last decades. This topic is important in many areas of signal processing such as, just to give some examples, radar, sonar, communications, and hyperspectral imaging. Most of the existing adaptive algorithms have been designed following the lead of the derivation of Kelly's detector which assumes perfect knowledge of the target steering vector. However, in realistic scenarios, mismatches are likely to occur due to both environmental and instrumental factors. When a mismatched signal

  9. Visual mismatch negativity reveals automatic detection of sequential regularity violation.

    Science.gov (United States)

    Stefanics, Gábor; Kimura, Motohiro; Czigler, István

    2011-01-01

    Sequential regularities are abstract rules based on repeating sequences of environmental events, which are useful to make predictions about future events. Here, we tested whether the visual system is capable to detect sequential regularity in unattended stimulus sequences. The visual mismatch negativity (vMMN) component of the event-related potentials is sensitive to the violation of complex regularities (e.g., object-related characteristics, temporal patterns). We used the vMMN component as an index of violation of conditional (if, then) regularities. In the first experiment, to investigate emergence of vMMN and other change-related activity to the violation of conditional rules, red and green disk patterns were delivered in pairs. The majority of pairs comprised of disk patterns with identical colors, whereas in deviant pairs the colors were different. The probabilities of the two colors were equal. The second member of the deviant pairs elicited a vMMN with longer latency and more extended spatial distribution to deviants with lower probability (10 vs. 30%). In the second (control) experiment the emergence of vMMN to violation of a simple, feature-related rule was studied using oddball sequences of stimulus pairs where deviant colors were presented with 20% probabilities. Deviant colored patterns elicited a vMMN, and this component was larger for the second member of the pair, i.e., after a shorter inter-stimulus interval. This result corresponds to the SOA/(v)MMN relationship, expected on the basis of a memory-mismatch process. Our results show that the system underlying vMMN is sensitive to abstract, conditional rules. Representation of such rules implicates expectation of a subsequent event, therefore vMMN can be considered as a correlate of violated predictions about the characteristics of environmental events.

  10. Technical aspects of typing for HLA-DP alleles using allele-specific DNA in vitro amplification and sequence-specific oligonucleotide probes. Detection of single base mismatches

    DEFF Research Database (Denmark)

    Fugger, L; Morling, N; Ryder, L P

    1990-01-01

    The polymerase chain reaction (PCR) is an effective method for in vitro DNA amplification which combined with probing with synthetic oligonucleotides can be used for, e.g., HLA-typing. We have studied the technical aspects of HLA-DP typing with the technique. DNA from mononuclear nucleated cells...... was extracted with either a simple salting out method or phenol/chloroform. Both DNAs could be readily used for PCR. The MgC2 concentration of the PCR buffer and the annealing temperature of the thermal cycle of the PCR were the two most important variables. The MgCl2 concentration and the temperature must...... be carefully titrated for each primer pair in the PCR. The influence of mismatches between the primer and the DNA template were studied and we found that, by using primers differing only from each other at the 3' end, cross-amplification of closely homologous alleles could be avoided. Thus, single base...

  11. Visual mismatch negativity reveals automatic detection of sequential regularity violation

    Directory of Open Access Journals (Sweden)

    Gábor eStefanics

    2011-05-01

    Full Text Available Sequential regularities are abstract rules based on repeating sequences of environmental events, which are useful to make predictions about future events. As the processes underlying visual mismatch negativity (vMMN are sensitive to complex stimulus changes, this event-related potential component, like its auditory counterpart, may be an index of a primitive system of intelligence. Here we tested whether the visual system is capable to detect abstract sequential regularity in unattended stimulus sequences. In our first experiment we investigated the emergence of vMMN and other change-related activity to stimuli violating abstract rules. Red and green disk patterns were delivered in pairs. When in the majority of pairs the colors were identical within the pairs, deviant pairs with different colors for the second member of the pair elicited vMMN. Spatially more extended vMMN responses with longer latency were observed for deviants with 10% compared to 30% probability. In our second experiment utilizing oddball sequences, we tested the emergence of vMMN to violations of a concrete, feature-based rule of a repetition of a standard color. Deviant colors elicited a vMMN response in the oddball sequences. VMMN was larger for the second member of the pair, i.e. after a shorter stimulus onset asynchrony (SOA. This result corresponds to the expected SOA/(vMMN relationship. Our results show that the system underlying vMMN is sensitive to abstract probability rules and this component can be considered as a correlate of violated predictions about the characteristics of environmental events.

  12. 1H NMR determination of base-pair lifetimes in oligonucleotides containing single base mismatches.

    Science.gov (United States)

    Bhattacharya, Pratip K; Cha, Julie; Barton, Jacqueline K

    2002-11-01

    Proton nuclear magnetic resonance (NMR) spectroscopy is employed to characterize the kinetics of base-pair opening in a series of 9mer duplexes containing different single base mismatches. The imino protons from the different mismatched, as well as fully matched, duplexes are assigned from the imino-imino region in the WATERGATE NOESY spectra. The exchange kinetics of the imino protons are measured from selective longitudinal relaxation times. In the limit of infinite exchange catalyst concentration, the exchange times of the mismatch imino protons extrapolate to much shorter lifetimes than are commonly observed for an isolated GC base pair. Different mismatches exhibit different orders of base-pair lifetimes, e.g. a TT mismatch has a shorter base-pair lifetime than a GG mismatch. The effect of the mismatch was observed up to a distance of two neighboring base pairs. This indicates that disruption in the duplex caused by the mismatch is quite localized. The overall order of base-pair lifetimes in the selected sequence context of the base pair is GC > GG > AA > CC > AT > TT. Interestingly, the fully matched AT base pair has a shorter base-pair lifetime relative to many of the mismatches. Thus, in any given base pair, the exchange lifetime can exhibit a strong dependence on sequence context. These findings may be relevant to the way mismatch recognition is accomplished by proteins and small molecules.

  13. Frontal Theta Activity Supports Detecting Mismatched Information in Visual Working Memory.

    Science.gov (United States)

    Liang, Tengfei; Hu, Zhonghua; Liu, Qiang

    2017-01-01

    During the comparison stage of visual working memory (VWM) processing, detecting the mismatch between the external sensory input and internal representations is a crucial cognitive ability for human, but the neural mechanism behind it remains largely unclear. The present study investigated the role of frontal theta power in detecting the mismatched information in VWM in a delayed matching task. A control task required to compare two simultaneously presented visual figures was also designed as a contrast to exclude the possibility that frontal theta activity just reflecting the non-memory-related behavioral conflicts. To better characterize the control mechanisms shaped by the frontal theta oscillation in human VWM, colored shapes were adopted as materials while both the task-relevant shape feature and task-irrelevant color feature could be mismatched. We found that the response times of participants were significantly delayed under the relevant- and irrelevant-mismatch conditions in both tasks and the conjunction-mismatch condition in delayed matching task. While our EEG data showed that increased frontal theta power was only observed under the relevant- and conjunction-mismatch conditions in the delayed matching task, but not the control task. These findings suggest that the frontal distributed theta activity observed here reflects the detection of mismatched information during the comparison stage of VWM, rather than the response-related conflicts. Furthermore, it is consistent with the proposal that theta-band oscillation can act as a control mechanism in working memory function so that the target-mismatched information in VWM could be successfully tracked. We also propose a possible processing structure to explain the neural dynamics underlying the mismatch detection process in VWM.

  14. Simple detection of germline microsatellite instability for diagnosis of constitutional mismatch repair cancer syndrome.

    Science.gov (United States)

    Ingham, Danielle; Diggle, Christine P; Berry, Ian; Bristow, Claire A; Hayward, Bruce E; Rahman, Nazneen; Markham, Alexander F; Sheridan, Eamonn G; Bonthron, David T; Carr, Ian M

    2013-06-01

    Heterozygous mutations in DNA mismatch repair (MMR) genes result in predisposition to colorectal cancer (hereditary nonpolyposis colorectal cancer or Lynch syndrome). Patients with biallelic mutations in these genes, however, present earlier, with constitutional mismatch repair deficiency cancer syndrome (CMMRD), which is characterized by a spectrum of rare childhood malignancies and café-au-lait skin patches. The hallmark of MMR deficiency, microsatellite instability (MSI), is readily detectable in tumor DNA in Lynch syndrome, but is also present in constitutional DNA of CMMRD patients. However, detection of constitutional or germline MSI (gMSI) has hitherto relied on technically difficult assays that are not routinely applicable for clinical diagnosis. Consequently, we have developed a simple high-throughput screening methodology to detect gMSI in CMMRD patients based on the presence of stutter peaks flanking a dinucleotide repeat allele when amplified from patient blood DNA samples. Using the three different microsatellite markers, the gMSI ratio was determined in a cohort of normal individuals and 10 CMMRD patients, with biallelic germline mutations in PMS2 (seven patients), MSH2 (one patient), or MSH6 (two patients). Subjects with either PMS2 or MSH2 mutations were easily identified; however, this measure was not altered in patients with CMMRD due to MSH6 mutation. © 2013 Wiley Periodicals, Inc.

  15. Femtomolar detection of single mismatches by discriminant analysis of DNA hybridization events using gold nanoparticles.

    Science.gov (United States)

    Ma, Xingyi; Sim, Sang Jun

    2013-03-21

    Even though DNA-based nanosensors have been demonstrated for quantitative detection of analytes and diseases, hybridization events have never been numerically investigated for further understanding of DNA mediated interactions. Here, we developed a nanoscale platform with well-designed capture and detection gold nanoprobes to precisely evaluate the hybridization events. The capture gold nanoprobes were mono-laid on glass and the detection probes were fabricated via a novel competitive conjugation method. The two kinds of probes combined in a suitable orientation following the hybridization with the target. We found that hybridization efficiency was markedly dependent on electrostatic interactions between DNA strands, which can be tailored by adjusting the salt concentration of the incubation solution. Due to the much lower stability of the double helix formed by mismatches, the hybridization efficiencies of single mismatched (MMT) and perfectly matched DNA (PMT) were different. Therefore, we obtained an optimized salt concentration that allowed for discrimination of MMT from PMT without stringent control of temperature or pH. The results indicated this to be an ultrasensitive and precise nanosensor for the diagnosis of genetic diseases.

  16. Mismatch repair status as a beneficial predictor of fluorouracil-based adjuvant chemotherapy for pancreatic cancer.

    Science.gov (United States)

    Liang, Dingkong; Shi, Si; Liang, Chen; Meng, Qingcai; Zhang, Bo; Ni, Quanxing; Xu, Jin; Yu, Xianjun

    2018-01-17

    Prior studies have indicated that patients with colorectal cancer with deficient mismatch repair have particular clinicopathologic features that distinguish them from patients with tumors with proficient mismatch repair. However, the effect of the mismatch repair status on outcomes after adjuvant chemotherapy for pancreatic cancer is still unknown. Pancreatic cancer patients who underwent R0 resection between January 2013 and December 2015 at Fudan University Shanghai Cancer Center were included in this study. Mismatch repair status was determined by immunohistochemistry of mismatch repair proteins. Prognostic factors for deficient mismatch repair and proficient mismatch repair tumors were analyzed using Cox models. In total, 442 of 590 patients met the inclusion criteria, and their mismatch repair status was determined; the study group consisted of 75 patients with deficient mismatch repair and 367 patients with proficient mismatch repair. Among the 147 patients who underwent surgery alone, patients with deficient mismatch repair tumors had a better overall survival than patients with proficient mismatch repair tumors (hazard ratio = 0.555 [95% confidence interval 0.331-0.931]; P = .026). Compared with patients who underwent surgery, 161 patients who received gemcitabine-based adjuvant chemotherapy had improvements in both disease-free survival and overall survival, regardless of mismatch repair status. However, 5-fluorouracil-based adjuvant chemotherapy yielded a favorable disease-free survival in the proficient mismatch repair group but conferred no survival advantage in the deficient mismatch repair group (hazard ratio = 0.930 [95% confidence interval 0.497-1.743]; P = .821). Mismatch repair status in pancreatic cancer patients is not only a prognostic indicator but also a potential guiding factor for the use of 5-fluorouracil-based adjuvant chemotherapy. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Characterizing sensitivity of longwave infrared hyperspectral target detection with respect to signature mismatch and dimensionality reduction

    Science.gov (United States)

    Meola, Joseph

    2017-05-01

    Hyperspectral target detection typically relies upon libraries of material reflectance and emissivity signatures. Application to real-world, airborne data requires estimation of atmospheric properties in order to convert reflectance/emissivity signatures to the sensor data domain. In the longwave infrared, an additional nuisance parameter of surface temperature exists that further complicates the signature conversion process. A significant amount of work has been done in atmospheric compensation and temperature-emissivity-separation techniques. This work examines the sensitivity of target detection performance for various materials with respect to target signature mismatch introduced from atmospheric compensation error or target temperature mismatch. Additionally, the impact of dimensionality reduction via principal components analysis is assessed.

  18. Rhythmic and melodic deviations in musical sequences recruit different cortical areas for mismatch detection

    Directory of Open Access Journals (Sweden)

    Claudia eLappe

    2013-06-01

    Full Text Available The mismatch negativity (MMN, an event-related potential (ERP representing the violation of an acoustic regularity, is considered as a pre-attentive change detection mechanism at the sensory level on the one hand and as a prediction error signal on the other hand, suggesting that bottom-up as well as top-down processes are involved in its generation. Rhythmic and melodic deviations within a musical sequence elicit a mismatch negativity in musically trained subjects, indicating that acquired musical expertise leads to better discrimination accuracy of musical material and better predictions about upcoming musical events. Expectation violations to musical material could therefore recruit neural generators that reflect top-down processes that are based on musical knowledge.We describe the neural generators of the musical MMN for rhythmic and melodic material after a short-term sensorimotor-auditory training. We compare the localization of musical MMN data from two previous MEG studies by applying beamformer analysis. One study focused on the melodic harmonic progression whereas the other study focused on rhythmic progression. The MMN to melodic deviations revealed significant right hemispheric neural activation in the superior temporal gyrus (STG, inferior frontal cortex (IFC, and the superior frontal (SFG and orbitofrontal (OFG gyri. IFC and SFG activation was also observed in the left hemisphere. In contrast, beamformer analysis of the data from the rhythm study revealed bilatral activation within the vicinity of auditory cortices and in the inferior parietal lobule, an area that has recently been implied in temporal processing. We conclude that different cortical networks are activated in the analysis of the temporal and the melodic content of musical material, and discuss these networks in the context of the the dual-pathway model of auditory processing.

  19. [Prevalence of altered mismatch repair protein nuclear expression detected by immunohistochemistry on adenomas with high-grade dysplasia and features associated with this risk in a population-based study].

    Science.gov (United States)

    Basterra, Marta; Gomez, Marta; Mercado, María Del Rosario; Irisarri, Rebeca; Amorena, Edurne; Arrospide, Arantzazu; Montes, Marta; Aisa, Gregorio; Cambra, Koldo Iñaki; Urman, Jesús

    2016-10-01

    Alteration of mismatch repair system protein expression detected by immunohistochemistry (IHQ) in tumoural tissue is a useful technique for Lynch Syndrome (LS) screening. A recent review proposes LS screening through immunohistochemical study not only in all diagnosed cases of colorectal cancer (CRC) but also in advanced adenomas, especially in young patients. To assess the prevalence of altered IHQ carried out in all adenomas with high-grade dysplasia (HGD) diagnosed in our community in 2011, as well as the variables associated with this alteration. We included all the cases of adenomatous polyps with HGD diagnosed in the three public pathology laboratories of Navarre during 2011 and performed a statistical study to assess the association between different patient and lesion characteristics and altered IHQ results. A total of 213 colonic adenomas with HGD were diagnosed, and 26 (12.2%) cases were excluded from the final analysis (2 known LS, 22 without IHQ study and 2 with inconclusive IHQ studies). The final number of adenomas included was 187. Pathologic results were found in 10 cases (5.35%)-6 cases in MLH1 and PMS2, 2 cases in PMS2, 1 case in MSH6 and 1 case in MSH2 and MSH6. The factors showing a statistically significant association with the presence of abnormal proteins were the synchronous presence of CRC, the presence of only one advanced adenoma, proximal location of HGD and age <50 years. The percentage of pathologic nuclear expression found in IHQ is high. Consequently, screening of all diagnosed HGD could be indicated, especially in young patients, with a single AA and proximal HGD. Copyright © 2015 Elsevier España, S.L.U. y AEEH y AEG. All rights reserved.

  20. Fast and quantitative differentiation of single-base mismatched DNA by initial reaction rate of catalytic hairpin assembly.

    Science.gov (United States)

    Li, Chenxi; Li, Yixin; Xu, Xiao; Wang, Xinyi; Chen, Yang; Yang, Xiaoda; Liu, Feng; Li, Na

    2014-10-15

    The widely used catalytic hairpin assembly (CHA) amplification strategy generally needs several hours to accomplish one measurement based on the prevailingly used maximum intensity detection mode, making it less practical for assays where high throughput or speed is desired. To make the best use of the kinetic specificity of toehold domain for circuit reaction initiation, we developed a mathematical model and proposed an initial reaction rate detection mode to quantitatively differentiate the single-base mismatch. Using the kinetic mode, assay time can be reduced substantially to 10 min for one measurement with the comparable sensitivity and single-base mismatch differentiating ability as were obtained by the maximum intensity detection mode. This initial reaction rate based approach not only provided a fast and quantitative differentiation of single-base mismatch, but also helped in-depth understanding of the CHA system, which will be beneficial to the design of highly sensitive and specific toehold-mediated hybridization reactions. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Rhythmic and melodic deviations in musical sequences recruit different cortical areas for mismatch detection.

    Science.gov (United States)

    Lappe, Claudia; Steinsträter, Olaf; Pantev, Christo

    2013-01-01

    The mismatch negativity (MMN), an event-related potential (ERP) representing the violation of an acoustic regularity, is considered as a pre-attentive change detection mechanism at the sensory level on the one hand and as a prediction error signal on the other hand, suggesting that bottom-up as well as top-down processes are involved in its generation. Rhythmic and melodic deviations within a musical sequence elicit a MMN in musically trained subjects, indicating that acquired musical expertise leads to better discrimination accuracy of musical material and better predictions about upcoming musical events. Expectation violations to musical material could therefore recruit neural generators that reflect top-down processes that are based on musical knowledge. We describe the neural generators of the musical MMN for rhythmic and melodic material after a short-term sensorimotor-auditory (SA) training. We compare the localization of musical MMN data from two previous MEG studies by applying beamformer analysis. One study focused on the melodic harmonic progression whereas the other study focused on rhythmic progression. The MMN to melodic deviations revealed significant right hemispheric neural activation in the superior temporal gyrus (STG), inferior frontal cortex (IFC), and the superior frontal (SFG) and orbitofrontal (OFG) gyri. IFC and SFG activation was also observed in the left hemisphere. In contrast, beamformer analysis of the data from the rhythm study revealed bilateral activation within the vicinity of auditory cortices and in the inferior parietal lobule (IPL), an area that has recently been implied in temporal processing. We conclude that different cortical networks are activated in the analysis of the temporal and the melodic content of musical material, and discuss these networks in the context of the dual-pathway model of auditory processing.

  2. Emotional intelligence and mismatching expressive and verbal messages: a contribution to detection of deception.

    Directory of Open Access Journals (Sweden)

    Jerzy Wojciechowski

    Full Text Available Processing facial emotion, especially mismatches between facial and verbal messages, is believed to be important in the detection of deception. For example, emotional leakage may accompany lying. Individuals with superior emotion perception abilities may then be more adept in detecting deception by identifying mismatch between facial and verbal messages. Two personal factors that may predict such abilities are female gender and high emotional intelligence (EI. However, evidence on the role of gender and EI in detection of deception is mixed. A key issue is that the facial processing skills required to detect deception may not be the same as those required to identify facial emotion. To test this possibility, we developed a novel facial processing task, the FDT (Face Decoding Test that requires detection of inconsistencies between facial and verbal cues to emotion. We hypothesized that gender and ability EI would be related to performance when cues were inconsistent. We also hypothesized that gender effects would be mediated by EI, because women tend to score as more emotionally intelligent on ability tests. Data were collected from 210 participants. Analyses of the FDT suggested that EI was correlated with superior face decoding in all conditions. We also confirmed the expected gender difference, the superiority of high EI individuals, and the mediation hypothesis. Also, EI was more strongly associated with facial decoding performance in women than in men, implying there may be gender differences in strategies for processing affective cues. It is concluded that integration of emotional and cognitive cues may be a core attribute of EI that contributes to the detection of deception.

  3. Emotional intelligence and mismatching expressive and verbal messages: a contribution to detection of deception.

    Science.gov (United States)

    Wojciechowski, Jerzy; Stolarski, Maciej; Matthews, Gerald

    2014-01-01

    Processing facial emotion, especially mismatches between facial and verbal messages, is believed to be important in the detection of deception. For example, emotional leakage may accompany lying. Individuals with superior emotion perception abilities may then be more adept in detecting deception by identifying mismatch between facial and verbal messages. Two personal factors that may predict such abilities are female gender and high emotional intelligence (EI). However, evidence on the role of gender and EI in detection of deception is mixed. A key issue is that the facial processing skills required to detect deception may not be the same as those required to identify facial emotion. To test this possibility, we developed a novel facial processing task, the FDT (Face Decoding Test) that requires detection of inconsistencies between facial and verbal cues to emotion. We hypothesized that gender and ability EI would be related to performance when cues were inconsistent. We also hypothesized that gender effects would be mediated by EI, because women tend to score as more emotionally intelligent on ability tests. Data were collected from 210 participants. Analyses of the FDT suggested that EI was correlated with superior face decoding in all conditions. We also confirmed the expected gender difference, the superiority of high EI individuals, and the mediation hypothesis. Also, EI was more strongly associated with facial decoding performance in women than in men, implying there may be gender differences in strategies for processing affective cues. It is concluded that integration of emotional and cognitive cues may be a core attribute of EI that contributes to the detection of deception.

  4. Emotional Intelligence and Mismatching Expressive and Verbal Messages: A Contribution to Detection of Deception

    Science.gov (United States)

    Wojciechowski, Jerzy; Stolarski, Maciej; Matthews, Gerald

    2014-01-01

    Processing facial emotion, especially mismatches between facial and verbal messages, is believed to be important in the detection of deception. For example, emotional leakage may accompany lying. Individuals with superior emotion perception abilities may then be more adept in detecting deception by identifying mismatch between facial and verbal messages. Two personal factors that may predict such abilities are female gender and high emotional intelligence (EI). However, evidence on the role of gender and EI in detection of deception is mixed. A key issue is that the facial processing skills required to detect deception may not be the same as those required to identify facial emotion. To test this possibility, we developed a novel facial processing task, the FDT (Face Decoding Test) that requires detection of inconsistencies between facial and verbal cues to emotion. We hypothesized that gender and ability EI would be related to performance when cues were inconsistent. We also hypothesized that gender effects would be mediated by EI, because women tend to score as more emotionally intelligent on ability tests. Data were collected from 210 participants. Analyses of the FDT suggested that EI was correlated with superior face decoding in all conditions. We also confirmed the expected gender difference, the superiority of high EI individuals, and the mediation hypothesis. Also, EI was more strongly associated with facial decoding performance in women than in men, implying there may be gender differences in strategies for processing affective cues. It is concluded that integration of emotional and cognitive cues may be a core attribute of EI that contributes to the detection of deception. PMID:24658500

  5. Mood As Cumulative Expectation Mismatch: A Test of Theory Based on Data from Non-verbal Cognitive Bias Tests

    Science.gov (United States)

    Raoult, Camille M. C.; Moser, Julia; Gygax, Lorenz

    2017-01-01

    Affective states are known to influence behavior and cognitive processes. To assess mood (moderately long-term affective states), the cognitive judgment bias test was developed and has been widely used in various animal species. However, little is known about how mood changes, how mood can be experimentally manipulated, and how mood then feeds back into cognitive judgment. A recent theory argues that mood reflects the cumulative impact of differences between obtained outcomes and expectations. Here expectations refer to an established context. Situations in which an established context fails to match an outcome are then perceived as mismatches of expectation and outcome. We take advantage of the large number of studies published on non-verbal cognitive bias tests in recent years (95 studies with a total of 162 independent tests) to test whether cumulative mismatch could indeed have led to the observed mood changes. Based on a criteria list, we assessed whether mismatch had occurred with the experimental procedure used to induce mood (mood induction mismatch), or in the context of the non-verbal cognitive bias procedure (testing mismatch). For the mood induction mismatch, we scored the mismatch between the subjects’ potential expectations and the manipulations conducted for inducing mood whereas, for the testing mismatch, we scored mismatches that may have occurred during the actual testing. We then investigated whether these two types of mismatch can predict the actual outcome of the cognitive bias study. The present evaluation shows that mood induction mismatch cannot well predict the success of a cognitive bias test. On the other hand, testing mismatch can modulate or even inverse the expected outcome. We think, cognitive bias studies should more specifically aim at creating expectation mismatch while inducing mood states to test the cumulative mismatch theory more properly. Furthermore, testing mismatch should be avoided as much as possible because it can

  6. Mood As Cumulative Expectation Mismatch: A Test of Theory Based on Data from Non-verbal Cognitive Bias Tests.

    Science.gov (United States)

    Raoult, Camille M C; Moser, Julia; Gygax, Lorenz

    2017-01-01

    Affective states are known to influence behavior and cognitive processes. To assess mood (moderately long-term affective states), the cognitive judgment bias test was developed and has been widely used in various animal species. However, little is known about how mood changes, how mood can be experimentally manipulated, and how mood then feeds back into cognitive judgment. A recent theory argues that mood reflects the cumulative impact of differences between obtained outcomes and expectations. Here expectations refer to an established context. Situations in which an established context fails to match an outcome are then perceived as mismatches of expectation and outcome. We take advantage of the large number of studies published on non-verbal cognitive bias tests in recent years (95 studies with a total of 162 independent tests) to test whether cumulative mismatch could indeed have led to the observed mood changes. Based on a criteria list, we assessed whether mismatch had occurred with the experimental procedure used to induce mood (mood induction mismatch), or in the context of the non-verbal cognitive bias procedure (testing mismatch). For the mood induction mismatch, we scored the mismatch between the subjects' potential expectations and the manipulations conducted for inducing mood whereas, for the testing mismatch, we scored mismatches that may have occurred during the actual testing. We then investigated whether these two types of mismatch can predict the actual outcome of the cognitive bias study. The present evaluation shows that mood induction mismatch cannot well predict the success of a cognitive bias test. On the other hand, testing mismatch can modulate or even inverse the expected outcome. We think, cognitive bias studies should more specifically aim at creating expectation mismatch while inducing mood states to test the cumulative mismatch theory more properly. Furthermore, testing mismatch should be avoided as much as possible because it can

  7. Mood As Cumulative Expectation Mismatch: A Test of Theory Based on Data from Non-verbal Cognitive Bias Tests

    Directory of Open Access Journals (Sweden)

    Camille M. C. Raoult

    2017-12-01

    Full Text Available Affective states are known to influence behavior and cognitive processes. To assess mood (moderately long-term affective states, the cognitive judgment bias test was developed and has been widely used in various animal species. However, little is known about how mood changes, how mood can be experimentally manipulated, and how mood then feeds back into cognitive judgment. A recent theory argues that mood reflects the cumulative impact of differences between obtained outcomes and expectations. Here expectations refer to an established context. Situations in which an established context fails to match an outcome are then perceived as mismatches of expectation and outcome. We take advantage of the large number of studies published on non-verbal cognitive bias tests in recent years (95 studies with a total of 162 independent tests to test whether cumulative mismatch could indeed have led to the observed mood changes. Based on a criteria list, we assessed whether mismatch had occurred with the experimental procedure used to induce mood (mood induction mismatch, or in the context of the non-verbal cognitive bias procedure (testing mismatch. For the mood induction mismatch, we scored the mismatch between the subjects’ potential expectations and the manipulations conducted for inducing mood whereas, for the testing mismatch, we scored mismatches that may have occurred during the actual testing. We then investigated whether these two types of mismatch can predict the actual outcome of the cognitive bias study. The present evaluation shows that mood induction mismatch cannot well predict the success of a cognitive bias test. On the other hand, testing mismatch can modulate or even inverse the expected outcome. We think, cognitive bias studies should more specifically aim at creating expectation mismatch while inducing mood states to test the cumulative mismatch theory more properly. Furthermore, testing mismatch should be avoided as much as possible

  8. A Comparison of Relative Time to Peak and Tmax for Mismatch-Based Patient Selection

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    Anke Wouters

    2017-10-01

    Full Text Available Background and purposeThe perfusion-weighted imaging (PWI/diffusion-weighted imaging (DWI mismatch profile is used to select patients for endovascular treatment. A PWI map of Tmax is commonly used to identify tissue with critical hypoperfusion. A time to peak (TTP map reflects similar hemodynamic properties with the added benefit that it does not require arterial input function (AIF selection and deconvolution. We aimed to determine if TTP could substitute Tmax for mismatch categorization.MethodsImaging data of the DEFUSE 2 trial were reprocessed to generate relative TTP (rTTP maps. We identified the rTTP threshold that yielded lesion volumes comparable to Tmax > 6 s and assessed the effect of reperfusion according to mismatch status, determined based on Tmax and rTTP volumes.ResultsAmong 102 included cases, the Tmax > 6 s lesion volumes corresponded most closely with rTTP > 4.5 s lesion volumes: median absolute difference 6.9 mL (IQR: 2.3–13.0. There was 94% agreement in mismatch classification between Tmax and rTTP-based criteria. When mismatch was assessed by Tmax criteria, the odds ratio (OR for favorable clinical response associated with reperfusion was 7.4 (95% CI 2.3–24.1 in patients with mismatch vs. 0.4 (95% CI 0.1–2.6 in patients without mismatch. When mismatch was assessed with rTTP criteria, these ORs were 7.2 (95% CI 2.3–22.2 and 0.3 (95% CI 0.1–2.2, respectively.ConclusionrTTP yields lesion volumes that are comparable to Tmax and reliably identifies the PWI/DWI mismatch profile. Since rTTP is void of the problems associated with AIF selection, it is a suitable substitute for Tmax that could improve the robustness and reproducibility of mismatch classification in acute stroke.

  9. A P300 brain-computer interface based on a modification of the mismatch negativity paradigm.

    Science.gov (United States)

    Jin, Jing; Sellers, Eric W; Zhou, Sijie; Zhang, Yu; Wang, Xingyu; Cichocki, Andrzej

    2015-05-01

    The P300-based brain-computer interface (BCI) is an extension of the oddball paradigm, and can facilitate communication for people with severe neuromuscular disorders. It has been shown that, in addition to the P300, other event-related potential (ERP) components have been shown to contribute to successful operation of the P300 BCI. Incorporating these components into the classification algorithm can improve the classification accuracy and information transfer rate (ITR). In this paper, a single character presentation paradigm was compared to a presentation paradigm that is based on the visual mismatch negativity. The mismatch negativity paradigm showed significantly higher classification accuracy and ITRs than a single character presentation paradigm. In addition, the mismatch paradigm elicited larger N200 and N400 components than the single character paradigm. The components elicited by the presentation method were consistent with what would be expected from a mismatch paradigm and a typical P300 was also observed. The results show that increasing the signal-to-noise ratio by increasing the amplitude of ERP components can significantly improve BCI speed and accuracy. The mismatch presentation paradigm may be considered a viable option to the traditional P300 BCI paradigm.

  10. Automatic Change Detection to Facial Expressions in Adolescents: Evidence from Visual Mismatch Negativity Responses

    Directory of Open Access Journals (Sweden)

    Tongran eLiu

    2016-03-01

    Full Text Available Adolescence is a critical period for the neurodevelopment of social-emotional processing, wherein the automatic detection of changes in facial expressions is crucial for the development of interpersonal communication. Two groups of participants (an adolescent group and an adult group were recruited to complete an emotional oddball task featuring on happy and one fearful condition. The measurement of event-related potential (ERP was carried out via electroencephalography (EEG and electrooculography (EOG recording, to detect visual mismatch negativity (vMMN with regard to the automatic detection of changes in facial expressions between the two age groups. The current findings demonstrated that the adolescent group featured more negative vMMN amplitudes than the adult group in the fronto-central region during the 120-200 ms interval. During the time window of 370-450 ms, only the adult group showed better automatic processing on fearful faces than happy faces. The present study indicated that adolescents posses stronger automatic detection of changes in emotional expression relative to adults, and sheds light on the neurodevelopment of automatic processes concerning social-emotional information.

  11. High affinity γPNA sandwich hybridization assay for rapid detection of short nucleic acid targets with single mismatch discrimination.

    Science.gov (United States)

    Goldman, Johnathan M; Zhang, Li Ang; Manna, Arunava; Armitage, Bruce A; Ly, Danith H; Schneider, James W

    2013-07-08

    Hybridization analysis of short DNA and RNA targets presents many challenges for detection. The commonly employed sandwich hybridization approach cannot be implemented for these short targets due to insufficient probe-target binding strengths for unmodified DNA probes. Here, we present a method capable of rapid and stable sandwich hybridization detection for 22 nucleotide DNA and RNA targets. Stable hybridization is achieved using an n-alkylated, polyethylene glycol γ-carbon modified peptide nucleic acid (γPNA) amphiphile. The γPNA's exceptionally high affinity enables stable hybridization of a second DNA-based probe to the remaining bases of the short target. Upon hybridization of both probes, an electrophoretic mobility shift is measured via interaction of the n-alkane modification on the γPNA with capillary electrophoresis running buffer containing nonionic surfactant micelles. We find that sandwich hybridization of both probes is stable under multiple binding configurations and demonstrate single base mismatch discrimination. The binding strength of both probes is also stabilized via coaxial stacking on adjacent hybridization to targets. We conclude with a discussion on the implementation of the proposed sandwich hybridization assay as a high-throughput microRNA detection method.

  12. Cytosine-Cytosine Base-Pair Mismatch and Chirality in Nucleotide Supramolecular Coordination Complexes.

    Science.gov (United States)

    Qiu, Qi-Ming; Zhou, Pei; Gu, Leilei; Hao, Liang; Liu, Minghua; Li, Hui

    2017-05-29

    The base-pair sequences are the foundation for the biological processes of DNA or RNA, and base-pair mismatch is very important to reveal genetic diseases and DNA rearrangements. However, the lack of well-defined structural information about base-pair mismatch is obstructing the investigation of this issue. The challenge is to crystallize the materials containing the base-pair mismatch. Engineering the small-molecule mimics or model is an effective strategy to solve this issue. Here, six cytidine-5'-monophosphate (CMP) and 2'-deoxycytidine-5'-monophosphate (dCMP) coordination polymers were reported containing cytosine-cytosine base-pair mismatch (i-motif), and their single-crystal structures and chiralities were studied. The precise control over the formation of the i-motif was demonstrated, in which the regulating of supramolecular interactions was achieved based on molecular design. In addition, the chiralities of these coordination polymers were investigated according to their crystal structures and solution- and solid-state circular dichroism spectroscopy. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Mismatch negativity to acoustical illusion of beat: how and where the change detection takes place?

    Science.gov (United States)

    Chakalov, Ivan; Paraskevopoulos, Evangelos; Wollbrink, Andreas; Pantev, Christo

    2014-10-15

    In case of binaural presentation of two tones with slightly different frequencies the structures of brainstem can no longer follow the interaural time differences (ITD) resulting in an illusionary perception of beat corresponding to frequency difference between the two prime tones. Hence, the beat-frequency does not exist in the prime tones presented to either ear. This study used binaural beats to explore the nature of acoustic deviance detection in humans by means of magnetoencephalography (MEG). Recent research suggests that the auditory change detection is a multistage process. To test this, we employed 26 Hz-binaural beats in a classical oddball paradigm. However, the prime tones (250 Hz and 276 Hz) were switched between the ears in the case of the deviant-beat. Consequently, when the deviant is presented, the cochleae and auditory nerves receive a "new afferent", although the standards and the deviants are heard identical (26 Hz-beats). This allowed us to explore the contribution of auditory periphery to change detection process, and furthermore, to evaluate its influence on beats-related auditory steady-state responses (ASSRs). LORETA-source current density estimates of the evoked fields in a typical mismatch negativity time-window (MMN) and the subsequent difference-ASSRs were determined and compared. The results revealed an MMN generated by a complex neural network including the right parietal lobe and the left middle frontal gyrus. Furthermore, difference-ASSR was generated in the paracentral gyrus. Additionally, psychophysical measures showed no perceptual difference between the standard- and deviant-beats when isolated by noise. These results suggest that the auditory periphery has an important contribution to novelty detection already at sub-cortical level. Overall, the present findings support the notion of hierarchically organized acoustic novelty detection system. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Detection of stimulus deviance within primate primary auditory cortex: intracortical mechanisms of mismatch negativity (MMN) generation.

    Science.gov (United States)

    Javitt, D C; Steinschneider, M; Schroeder, C E; Vaughan, H G; Arezzo, J C

    1994-12-26

    Mismatch negativity (MMN) is a cognitive, auditory event-related potential (AEP) that reflects preattentive detection of stimulus deviance and indexes the operation of the auditory sensory ('echoic') memory system. MMN is elicited most commonly in an auditory oddball paradigm in which a sequence of repetitive standard stimuli is interrupted infrequently and unexpectedly by a physically deviant 'oddball' stimulus. Electro- and magnetoencephalographic dipole mapping studies have localized the generators of MMN to supratemporal auditory cortex in the vicinity of Heschl's gyrus, but have not determined the degree to which MMN reflects activation within primary auditory cortex (AI) itself. The present study, using moveable multichannel electrodes inserted acutely into superior temporal plane, demonstrates a significant contribution of AI to scalp-recorded MMN in the monkey, as reflected by greater response of AI to loud or soft clicks presented as deviants than to the same stimuli presented as repetitive standards. The MMN-like activity was localized primarily to supragranular laminae within AI. Thus, standard and deviant stimuli elicited similar degrees of initial, thalamocortical excitation. In contrast, responses within supragranular cortex were significantly larger to deviant stimuli than to standards. No MMN-like activity was detected in a limited number to passes that penetrated anterior and medial to AI. AI plays a well established role in the decoding of the acoustic properties of individual stimuli. The present study demonstrates that primary auditory cortex also plays an important role in processing the relationships between stimuli, and thus participates in cognitive, as well as purely sensory, processing of auditory information.

  15. A temporal constraint for automatic deviance detection and object formation: A mismatch negativity study.

    Science.gov (United States)

    Weise, Annekathrin; Grimm, Sabine; Müller, Dagmar; Schröger, Erich

    2010-05-17

    The automatic detection of deviations within a constant sine wave tone is confined to the initial part of approximately 350 ms. When a deviation occurs beyond this critical limit, the mismatch negativity (MMN) - a deviance-related component of the event-related potential - is largely attenuated or even absent. However, for time-variant acoustic stimuli such as speech sounds or tonal patterns, MMN is also obtained for deviations beyond the initial 350 ms. We consider two hypotheses that can explain the MMN to time-variant sounds. One is that the terminal part of those sounds is represented as the spectral information varies over time (spectral-variation hypothesis). The other is that transients, occurring in time-variant signals, help to segment the long sounds into smaller units, each being not larger than the critical 350 ms (segmentation hypothesis). We measured MMN to duration shortenings (deviants) embedded in a sequence of 1000 ms long standard tones of increasing frequency (sweeps). The sweeps did or did not contain a noise burst. Results reveal a lack of MMN to the duration deviant in the sweep without a noise burst, which rules out the spectral-variation hypothesis. The presence of MMN to the duration deviant in the sweep with a noise burst supports the segmentation hypothesis. Thus, the results suggest a temporal constraint inherent to the processing of unstructured/unsegmented long tones. We argue that transients within a sound act as segmentation cues providing an automatic sound representation for which deviations can be detected. Copyright 2010 Elsevier B.V. All rights reserved.

  16. Phase Error Caused by Speed Mismatch Analysis in the Line-Scan Defect Detection by Using Fourier Transform Technique

    Directory of Open Access Journals (Sweden)

    Eryi Hu

    2015-01-01

    Full Text Available The phase error caused by the speed mismatch issue is researched in the line-scan images capturing 3D profile measurement. The experimental system is constructed by a line-scan CCD camera, an object moving device, a digital fringe pattern projector, and a personal computer. In the experiment procedure, the detected object is moving relative to the image capturing system by using a motorized translation stage in a stable velocity. The digital fringe pattern is projected onto the detected object, and then the deformed patterns are captured and recorded in the computer. The object surface profile can be calculated by the Fourier transform profilometry. However, the moving speed mismatch error will still exist in most of the engineering application occasion even after an image system calibration. When the moving speed of the detected object is faster than the expected value, the captured image will be compressed in the moving direction of the detected object. In order to overcome this kind of measurement error, an image recovering algorithm is proposed to reconstruct the original compressed image. Thus, the phase values can be extracted much more accurately by the reconstructed images. And then, the phase error distribution caused by the speed mismatch is analyzed by the simulation and experimental methods.

  17. Detection of coding microsatellite frameshift mutations in DNA mismatch repair-deficient mouse intestinal tumors.

    Science.gov (United States)

    Woerner, Stefan M; Tosti, Elena; Yuan, Yan P; Kloor, Matthias; Bork, Peer; Edelmann, Winfried; Gebert, Johannes

    2015-11-01

    Different DNA mismatch repair (MMR)-deficient mouse strains have been developed as models for the inherited cancer predisposing Lynch syndrome. It is completely unresolved, whether coding mononucleotide repeat (cMNR) gene mutations in these mice can contribute to intestinal tumorigenesis and whether MMR-deficient mice are a suitable molecular model of human microsatellite instability (MSI)-associated intestinal tumorigenesis. A proof-of-principle study was performed to identify mouse cMNR-harboring genes affected by insertion/deletion mutations in MSI murine intestinal tumors. Bioinformatic algorithms were developed to establish a database of mouse cMNR-harboring genes. A panel of five mouse noncoding mononucleotide markers was used for MSI classification of intestinal matched normal/tumor tissues from MMR-deficient (Mlh1(-/-) , Msh2(-/-) , Msh2(LoxP/LoxP) ) mice. cMNR frameshift mutations of candidate genes were determined by DNA fragment analysis. Murine MSI intestinal tumors but not normal tissues from MMR-deficient mice showed cMNR frameshift mutations in six candidate genes (Elavl3, Tmem107, Glis2, Sdccag1, Senp6, Rfc3). cMNRs of mouse Rfc3 and Elavl3 are conserved in type and length in their human orthologs that are known to be mutated in human MSI colorectal, endometrial and gastric cancer. We provide evidence for the utility of a mononucleotide marker panel for detection of MSI in murine tumors, the existence of cMNR instability in MSI murine tumors, the utility of mouse subspecies DNA for identification of polymorphic repeats, and repeat conservation among some orthologous human/mouse genes, two of them showing instability in human and mouse MSI intestinal tumors. MMR-deficient mice hence are a useful molecular model system for analyzing MSI intestinal carcinogenesis. © 2014 Wiley Periodicals, Inc.

  18. MEASURES OF OCCUPATIONAL MISMATCH

    Directory of Open Access Journals (Sweden)

    Monica Mihaela MAER MATEI

    2014-11-01

    Full Text Available The research developed in this paper is based on micro data available in Programme for the International Assessment of Adult Competencies (PIAAC. The research aimed to estimate the size of both forms of labour market mismatch: education mismatch and skill mismatch. The first measure of job mismatch is based on workers’ self-assessment. The second one uses the PIAAC assessment regarding the proficiency for each skill dimension (literacy, numeracy and problem solving in technology rich environments. The labor market mismatch was measured for Spain and Italy datasets for the higher education graduates whose occupations are included in Major Group two Professionals, according to the International Standard Classification of Occupations. The estimation results showed that the two measures of labour market mismatch are not correlated.

  19. Chimeric proteins for detection and quantitation of DNA mutations, DNA sequence variations, DNA damage and DNA mismatches

    Science.gov (United States)

    McCutchen-Maloney, Sandra L.

    2002-01-01

    Chimeric proteins having both DNA mutation binding activity and nuclease activity are synthesized by recombinant technology. The proteins are of the general formula A-L-B and B-L-A where A is a peptide having DNA mutation binding activity, L is a linker and B is a peptide having nuclease activity. The chimeric proteins are useful for detection and identification of DNA sequence variations including DNA mutations (including DNA damage and mismatches) by binding to the DNA mutation and cutting the DNA once the DNA mutation is detected.

  20. Epistatic role of base excision repair and mismatch repair pathways in mediating cisplatin cytotoxicity

    Science.gov (United States)

    Kothandapani, Anbarasi; Sawant, Akshada; Dangeti, Venkata Srinivas Mohan Nimai; Sobol, Robert W.; Patrick, Steve M.

    2013-01-01

    Base excision repair (BER) and mismatch repair (MMR) pathways play an important role in modulating cis-Diamminedichloroplatinum (II) (cisplatin) cytotoxicity. In this article, we identified a novel mechanistic role of both BER and MMR pathways in mediating cellular responses to cisplatin treatment. Cells defective in BER or MMR display a cisplatin-resistant phenotype. Targeting both BER and MMR pathways resulted in no additional resistance to cisplatin, suggesting that BER and MMR play epistatic roles in mediating cisplatin cytotoxicity. Using a DNA Polymerase β (Polβ) variant deficient in polymerase activity (D256A), we demonstrate that MMR acts downstream of BER and is dependent on the polymerase activity of Polβ in mediating cisplatin cytotoxicity. MSH2 preferentially binds a cisplatin interstrand cross-link (ICL) DNA substrate containing a mismatch compared with a cisplatin ICL substrate without a mismatch, suggesting a novel mutagenic role of Polβ in activating MMR in response to cisplatin. Collectively, these results provide the first mechanistic model for BER and MMR functioning within the same pathway to mediate cisplatin sensitivity via non-productive ICL processing. In this model, MMR participation in non-productive cisplatin ICL processing is downstream of BER processing and dependent on Polβ misincorporation at cisplatin ICL sites, which results in persistent cisplatin ICLs and sensitivity to cisplatin. PMID:23761438

  1. Detection of mismatch repair gene germline mutation carrier among Chinese population with colorectal cancer

    International Nuclear Information System (INIS)

    Jin, Hei-Ying; Zhao, Ronghua; Liu, Xiufang; Li, Vicky Ka Ming; Ding, Yijiang; Yang, Bolin; Geng, Jianxiang; Lai, Rensheng; Ding, Shuqing; Ni, Min

    2008-01-01

    Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant syndrome. The National Cancer Institute (NCI) has recommended the Revised Bethesda guidelines for screening HNPCC. There has been a great deal of research on the value of these tests in other countries. However, literature about the Chinese population is scarce. Our objective is to detect and study microsatellite instability (MSI) and mismatch repair (MMR) gene germline mutation carriers among a Chinese population with colorectal cancer. In 146 prospectively recruited consecutive patients with clinically proven colorectal cancer, MSI carriers were identified by analysis of tumor tissue using multiplex fluorescence polymerase chain reaction (PCR) using the NCI recommended panel and classified into microsatellite instability-low (MSI-L), microsatellite instability-high (MSI-H) and microsatellite stable (MSS) groups. Immunohistochemical staining for MSH2, MSH6 and MLH1 on tissue microarrays (TMAs) was performed, and methylation of the MLH1 promoter was analyzed by quantitative methylation specific PCR (MSP). Germline mutation analysis of blood samples was performed for MSH2, MSH6 and MLH1 genes. Thirty-four out of the 146 colorectal cancers (CRCs, 23.2%) were MSI, including 19 MSI-H CRCs and 15 MSI-L CRCS. Negative staining for MSH2 was found in 8 CRCs, negative staining for MSH6 was found in 6 CRCs. One MSI-H CRC was negative for both MSH6 and MSH2. Seventeen CRCs stained negatively for MLH1. MLH1 promoter methylation was determined in 34 MSI CRCs. Hypermethylation of the MLH1 promoter occurred in 14 (73.7%) out of 19 MSI-H CRCs and 5 (33.3%) out of 15 MSI-L CRCs. Among the 34 MSI carriers and one MSS CRC with MLH1 negative staining, 8 had a MMR gene germline mutation, which accounted for 23.5% of all MSI colorectal cancers and 5.5% of all the colorectal cancers. Five patients harbored MSH2 germline mutations, and three patients harbored MSH6 germline mutations. None of the patients had an MLH

  2. Performance Analysis of Spectral Amplitude Coding Based OCDMA System with Gain and Splitter Mismatch

    Science.gov (United States)

    Umrani, Fahim A.; Umrani, A. Waheed; Umrani, Naveed A.; Memon, Kehkashan A.; Kalwar, Imtiaz Hussain

    2013-09-01

    This paper presents the practical analysis of the optical code-division multiple-access (O-CDMA) systems based on perfect difference codes. The work carried out use SNR criterion to select the optimal value of avalanche photodiodes (APD) gain and shows how the mismatch in the splitters and gains of the APD used in the transmitters and receivers of network can degrade the BER performance of the system. The investigations also reveal that higher APD gains are not suitable for such systems even at higher powers. The system performance, with consideration of shot noise, thermal noise, bulk and surface leakage currents is also investigated.

  3. Compensating Acoustic Mismatch Using Class-Based Histogram Equalization for Robust Speech Recognition

    Directory of Open Access Journals (Sweden)

    Hoirin Kim

    2007-01-01

    Full Text Available A new class-based histogram equalization method is proposed for robust speech recognition. The proposed method aims at not only compensating for an acoustic mismatch between training and test environments but also reducing the two fundamental limitations of the conventional histogram equalization method, the discrepancy between the phonetic distributions of training and test speech data, and the nonmonotonic transformation caused by the acoustic mismatch. The algorithm employs multiple class-specific reference and test cumulative distribution functions, classifies noisy test features into their corresponding classes, and equalizes the features by using their corresponding class reference and test distributions. The minimum mean-square error log-spectral amplitude (MMSE-LSA-based speech enhancement is added just prior to the baseline feature extraction to reduce the corruption by additive noise. The experiments on the Aurora2 database proved the effectiveness of the proposed method by reducing relative errors by 62% over the mel-cepstral-based features and by 23% over the conventional histogram equalization method, respectively.

  4. Positive cooperativity of the specific binding between Hg2+ ion and T:T mismatched base pairs in duplex DNA

    International Nuclear Information System (INIS)

    Torigoe, Hidetaka; Miyakawa, Yukako; Ono, Akira; Kozasa, Tetsuo

    2012-01-01

    Highlights: ► Hg 2+ specifically bound with the T:T mismatched base pair at 1:1 molar ratio. ► The binding constant between Hg 2+ and the T:T mismatched base pair was 10 6 M −1 . ► The binding constant was larger than those for nonspecific metal–DNA interactions. ► The binding constant for the second Hg 2+ was larger than that for the first Hg 2+ . ► The positive cooperative binding was observed between Hg 2+ and multiple T:T. - Abstract: Metal-mediated base pairs by the interaction between metal ions and artificial bases in oligonucleotides have been developed for their potential applications in nanotechnology. We recently found that a natural T:T mismatched base pair bound with Hg 2+ ion to form a novel T–Hg–T base pair. Here, we examined the thermodynamic properties of the binding between Hg 2+ and each of the single and double T:T mismatched base pair duplex DNAs by isothermal titration calorimetry. Hg 2+ specifically bound with the T:T mismatched base pair at 1:1 molar ratio with 10 6 M −1 binding constant, which was significantly larger than those for nonspecific metal ion–DNA interactions. In the Hg 2+ –double T:T mismatched base pair interaction, the affinity for the second Hg 2+ binding was significantly larger than that for the first Hg 2+ binding. The positively cooperative binding may be favorable to align multiple Hg 2+ in duplex DNA for the application of the metal-mediated base pairs in nanotechnology.

  5. Pms2 and uracil-DNA glycosylases act jointly in the mismatch repair pathway to generate Ig gene mutations at A-T base pairs.

    Science.gov (United States)

    Girelli Zubani, Giulia; Zivojnovic, Marija; De Smet, Annie; Albagli-Curiel, Olivier; Huetz, François; Weill, Jean-Claude; Reynaud, Claude-Agnès; Storck, Sébastien

    2017-04-03

    During somatic hypermutation (SHM) of immunoglobulin genes, uracils introduced by activation-induced cytidine deaminase are processed by uracil-DNA glycosylase (UNG) and mismatch repair (MMR) pathways to generate mutations at G-C and A-T base pairs, respectively. Paradoxically, the MMR-nicking complex Pms2/Mlh1 is apparently dispensable for A-T mutagenesis. Thus, how detection of U:G mismatches is translated into the single-strand nick required for error-prone synthesis is an open question. One model proposed that UNG could cooperate with MMR by excising a second uracil in the vicinity of the U:G mismatch, but it failed to explain the low impact of UNG inactivation on A-T mutagenesis. In this study, we show that uracils generated in the G1 phase in B cells can generate equal proportions of A-T and G-C mutations, which suggests that UNG and MMR can operate within the same time frame during SHM. Furthermore, we show that Ung -/- Pms2 -/- mice display a 50% reduction in mutations at A-T base pairs and that most remaining mutations at A-T bases depend on two additional uracil glycosylases, thymine-DNA glycosylase and SMUG1. These results demonstrate that Pms2/Mlh1 and multiple uracil glycosylases act jointly, each one with a distinct strand bias, to enlarge the immunoglobulin gene mutation spectrum from G-C to A-T bases. © 2017 Girelli Zubani et al.

  6. Disturbance observer based sliding mode control of nonlinear mismatched uncertain systems

    Science.gov (United States)

    Ginoya, Divyesh; Shendge, P. D.; Phadke, S. B.

    2015-09-01

    This paper presents a new design of multiple-surface sliding mode control for a class of nonlinear uncertain systems with mismatched uncertainties and disturbances. In the method of multiple-surface sliding mode control, it is required to compensate for the derivatives of the virtual inputs which gives rise to the so-called problem of 'explosion of terms'. In this paper a disturbance observer based multiple-surface sliding mode control is proposed to estimate the uncertainties as well as the derivative of the virtual inputs to overcome this problem. The practical stability of the overall system is proved. The effectiveness of the proposed control strategy is illustrated via simulation of a benchmark problem and comparison with other control strategies. The proposed scheme is validated by implementing it on a serial flexible joint manipulator in the laboratory.

  7. Accurate and visual discrimination of single-base mismatch by utilization of binary DNA probes in gold nanoparticles-based biosensing strategy.

    Science.gov (United States)

    Zhou, Weijun; Ren, Jiangtao; Zhu, Jinbo; Zhou, Zhixue; Dong, Shaojun

    2016-12-01

    Herein we report a colorimetric biosensing strategy to discriminate single-nucleotide mutation in DNA with high selectivity using unmodified gold nanoparticles (AuNPs) as indicators. In the AuNPs-based colorimetric strategy, binary DNA probes were produced by splitting a long DNA probe in the middle for sensitive differentiation of single-base mismatch. The detection limit of this method toward target DNA was 5nM. The developed system has superior advantages of utilization of inexpensive materials, simplicity and visualization. Moreover, binary DNA probes not only can distinguish single-base mutation in the target DNA very well, as compared to long DNA probe, but also can construct "AND" logic gate using two distinct target DNAs as inputs, which holds great potential for increasing the accuracy of disease diagnosis in clinical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. SPATIAL MISMATCH OR RACIAL MISMATCH?*

    Science.gov (United States)

    Hellerstein, Judith K.; Neumark, David; McInerney, Melissa

    2008-01-01

    We contrast the spatial mismatch hypothesis with what we term the racial mismatch hypothesis – that the problem is not a lack of jobs, per se, where blacks live, but a lack of jobs where blacks live into which blacks are hired. We first report new evidence on the spatial mismatch hypothesis, using data from Census Long-Form respondents. We construct direct measures of the presence of jobs in detailed geographic areas, and find that these job density measures are related to employment of black male residents in ways that would be predicted by the spatial mismatch hypothesis – in particular that spatial mismatch is primarily an issue for low-skilled black male workers. We then look at mismatch along not only spatial lines but racial lines as well, by estimating the effects of job density measures that are disaggregated by race. We find that it is primarily black job density that influences black male employment, whereas white job density has little if any influence on their employment. The evidence implies that space alone plays a relatively minor role in low black male employment rates. PMID:19727422

  9. Postreplicative Mismatch Repair

    Science.gov (United States)

    Jiricny, Josef

    2013-01-01

    The mismatch repair (MMR) system detects non-Watson–Crick base pairs and strand misalignments arising during DNA replication and mediates their removal by catalyzing excision of the mispair-containing tract of nascent DNA and its error-free resynthesis. In this way, MMR improves the fidelity of replication by several orders of magnitude. It also addresses mispairs and strand misalignments arising during recombination and prevents synapses between nonidentical DNA sequences. Unsurprisingly, MMR malfunction brings about genomic instability that leads to cancer in mammals. But MMR proteins have recently been implicated also in other processes of DNA metabolism, such as DNA damage signaling, antibody diversification, and repair of interstrand cross-links and oxidative DNA damage, in which their functions remain to be elucidated. This article reviews the progress in our understanding of the mechanism of replication error repair made during the past decade. PMID:23545421

  10. DREMECELS: A Curated Database for Base Excision and Mismatch Repair Mechanisms Associated Human Malignancies.

    Directory of Open Access Journals (Sweden)

    Ankita Shukla

    Full Text Available DNA repair mechanisms act as a warrior combating various damaging processes that ensue critical malignancies. DREMECELS was designed considering the malignancies with frequent alterations in DNA repair pathways, that is, colorectal and endometrial cancers, associated with Lynch syndrome (also known as HNPCC. Since lynch syndrome carries high risk (~40-60% for both cancers, therefore we decided to cover all three diseases in this portal. Although a large population is presently affected by these malignancies, many resources are available for various cancer types but no database archives information on the genes specifically for only these cancers and disorders. The database contains 156 genes and two repair mechanisms, base excision repair (BER and mismatch repair (MMR. Other parameters include some of the regulatory processes that have roles in these disease progressions due to incompetent repair mechanisms, specifically BER and MMR. However, our unique database mainly provides qualitative and quantitative information on these cancer types along with methylation, drug sensitivity, miRNAs, copy number variation (CNV and somatic mutations data. This database would serve the scientific community by providing integrated information on these disease types, thus sustaining diagnostic and therapeutic processes. This repository would serve as an excellent accompaniment for researchers and biomedical professionals and facilitate in understanding such critical diseases. DREMECELS is publicly available at http://www.bioinfoindia.org/dremecels.

  11. Total variation-based method for radar coincidence imaging with model mismatch for extended target

    Science.gov (United States)

    Cao, Kaicheng; Zhou, Xiaoli; Cheng, Yongqiang; Fan, Bo; Qin, Yuliang

    2017-11-01

    Originating from traditional optical coincidence imaging, radar coincidence imaging (RCI) is a staring/forward-looking imaging technique. In RCI, the reference matrix must be computed precisely to reconstruct the image as preferred; unfortunately, such precision is almost impossible due to the existence of model mismatch in practical applications. Although some conventional sparse recovery algorithms are proposed to solve the model-mismatch problem, they are inapplicable to nonsparse targets. We therefore sought to derive the signal model of RCI with model mismatch by replacing the sparsity constraint item with total variation (TV) regularization in the sparse total least squares optimization problem; in this manner, we obtain the objective function of RCI with model mismatch for an extended target. A more robust and efficient algorithm called TV-TLS is proposed, in which the objective function is divided into two parts and the perturbation matrix and scattering coefficients are updated alternately. Moreover, due to the ability of TV regularization to recover sparse signal or image with sparse gradient, TV-TLS method is also applicable to sparse recovering. Results of numerical experiments demonstrate that, for uniform extended targets, sparse targets, and real extended targets, the algorithm can achieve preferred imaging performance both in suppressing noise and in adapting to model mismatch.

  12. Mismatch Repair*

    Science.gov (United States)

    Fishel, Richard

    2015-01-01

    Highly conserved MutS homologs (MSH) and MutL homologs (MLH/PMS) are the fundamental components of mismatch repair (MMR). After decades of debate, it appears clear that the MSH proteins initiate MMR by recognizing a mismatch and forming multiple extremely stable ATP-bound sliding clamps that diffuse without hydrolysis along the adjacent DNA. The function(s) of MLH/PMS proteins is less clear, although they too bind ATP and are targeted to MMR by MSH sliding clamps. Structural analysis combined with recent real-time single molecule and cellular imaging technologies are providing new and detailed insight into the thermal-driven motions that animate the complete MMR mechanism. PMID:26354434

  13. Automated detection of residual cells after sex-mismatched stem-cell transplantation – evidence for presence of disease-marker negative residual cells

    Directory of Open Access Journals (Sweden)

    Johannes Tilman

    2009-05-01

    Full Text Available Abstract Background A new chimerism analysis based on automated interphase fluorescence in situ hybridization (FISH evaluation was established to detect residual cells after allogene sex-mismatched bone marrow or blood stem-cell transplantation. Cells of 58 patients were characterized as disease-associated due to presence of a bcr/abl-gene-fusion or a trisomy 8 and/or a simultaneous hybridization of gonosome-specific centromeric probes. The automatic slide scanning platform Metafer with its module MetaCyte was used to analyse 3,000 cells per sample. Results Overall 454 assays of 58 patients were analyzed. 13 of 58 patients showed residual recipient cells at one stage of more than 4% and 12 of 58 showed residual recipient cells less than 4%, respectively. As to be expected, patients of the latter group were associated with a higher survival rate (48 vs. 34 month. In only two of seven patients with disease-marker positive residual cells between 0.1–1.3% a relapse was observed. Besides, disease-marker negative residual cells were found in two patients without relapse at a rate of 2.8% and 3.3%, respectively. Conclusion The definite origin and meaning of disease-marker negative residual cells is still unclear. Overall, with the presented automatic chimerism analysis of interphase FISH slides, a sensitive method for detection of disease-marker positive residual cells is on hand.

  14. Continuous uniformly finite time exact disturbance observer based control for fixed-time stabilization of nonlinear systems with mismatched disturbances.

    Science.gov (United States)

    Ni, Junkang; Liu, Chongxin; Liu, Hang

    2017-01-01

    This paper presents a continuous composite control scheme to achieve fixed-time stabilization for nonlinear systems with mismatched disturbances. The composite controller is constructed in two steps: First, uniformly finite time exact disturbance observers are proposed to estimate and compensate the disturbances. Then, based on adding a power integrator technique and fixed-time stability theory, continuous fixed-time stable state feedback controller and Lyapunov functions are constructed to achieve global fixed-time system stabilization. The proposed control method extends the existing fixed-time stable control results to high order nonlinear systems with mismatched disturbances and achieves global fixed-time system stabilization. Besides, the proposed control scheme improves the disturbance rejection performance and achieves performance recovery of nominal system. Simulation results are provided to show the effectiveness, the superiority and the applicability of the proposed control scheme.

  15. Allele identification using immobilized mismatch binding protein: detection and identification of antibiotic-resistant bacteria and determination of sheep susceptibility to scrapie.

    OpenAIRE

    Debbie, P; Young, K; Pooler, L; Lamp, C; Marietta, P; Wagner, R

    1997-01-01

    A novel method for detection and identification of specific alleles has been developed utilizing immobilized mismatch binding protein (IMBP). The assay involves the use of biotin-labeled probes, which are prepared by PCR amplification of cloned fragments with known sequence. The use of probes avoids many of the problems associated with the extreme sensitivity of IMBP assays to errors in PCR amplification. The method can be used to monitor PCR fidelity and to genotype both diploid and haploid ...

  16. Reliable Detection of Mismatch Repair Deficiency in Colorectal Cancers Using Mutational Load in Next-Generation Sequencing Panels

    Science.gov (United States)

    Stadler, Zsofia K.; Battaglin, Francesca; Middha, Sumit; Hechtman, Jaclyn F.; Tran, Christina; Cercek, Andrea; Yaeger, Rona; Segal, Neil H.; Varghese, Anna M.; Reidy-Lagunes, Diane L.; Kemeny, Nancy E.; Salo-Mullen, Erin E.; Ashraf, Asad; Weiser, Martin R.; Garcia-Aguilar, Julio; Robson, Mark E.; Offit, Kenneth; Arcila, Maria E.; Berger, Michael F.; Shia, Jinru; Solit, David B.

    2016-01-01

    Purpose Tumor screening for Lynch syndrome is recommended in all or most patients with colorectal cancer (CRC). In metastatic CRC, sequencing of RAS/BRAF is necessary to guide clinical management. We hypothesized that a next-generation sequencing (NGS) panel that identifies RAS/BRAF and other actionable mutations could also reliably identify tumors with DNA mismatch repair protein deficiency (MMR-D) on the basis of increased mutational load. Methods We identified all CRCs that underwent genomic mutation profiling with a custom NGS assay (MSK-IMPACT) between March 2014 and July 2015. Tumor mutational load, with exclusion of copy number changes, was determined for each case and compared with MMR status as determined by routine immunohistochemistry. Results Tumors from 224 patients with unique CRC analyzed for MMR status also underwent MSK-IMPACT. Thirteen percent (n = 28) exhibited MMR-D by immunohistochemistry. Using the 341-gene assay, 100% of the 193 tumors with 150 mutations each. Each of these tumors harbored the P286R hotspot POLE mutation consistent with the ultramutator phenotype. Among MMR-D tumors, the median number of mutations was 50 (range, 20 to 90) compared with six (range, 0 to 17) in MMR-proficient/POLE wild-type tumors (P < .001). With a mutational load cutoff of ≥ 20 and < 150 for MMR-D detection, sensitivity and specificity were both 1.0 (95% CI, 0.93 to 1.0). Conclusion A cutoff for mutational load can be identified via multigene NGS tumor profiling, which provides a highly accurate means of screening for MMR-D in the same assay that is used for tumor genotyping. PMID:27022117

  17. Estimation of channel mismatches in time-interleaved analog-to-digital converters based on fractional delay and sine curve fitting.

    Science.gov (United States)

    Guo, Lianping; Tian, Shulin; Jiang, Jun

    2015-03-01

    This paper proposes an algorithm to estimate the channel mismatches in time-interleaved analog-to-digital converter (TIADC) based on fractional delay (FD) and sine curve fitting. Choose one channel as the reference channel and apply FD to the output samples of reference channel to obtain the ideal samples of non-reference channels with no mismatches. Based on least square method, the sine curves are adopted to fit the ideal and the actual samples of non-reference channels, and then the mismatch parameters can be estimated by comparing the ideal sine curves and the actual ones. The principle of this algorithm is simple and easily understood. Moreover, its implementation needs no extra circuits, lowering the hardware cost. Simulation results show that the estimation accuracy of this algorithm can be controlled within 2%. Finally, the practicability of this algorithm is verified by the measurement results of channel mismatch errors of a two-channel TIADC prototype.

  18. ASPECTS (Alberta Stroke Program Early CT Score) Assessment of the Perfusion-Diffusion Mismatch.

    Science.gov (United States)

    Lassalle, Louis; Turc, Guillaume; Tisserand, Marie; Charron, Sylvain; Roca, Pauline; Lion, Stephanie; Legrand, Laurence; Edjlali, Myriam; Naggara, Olivier; Meder, Jean-François; Mas, Jean-Louis; Baron, Jean-Claude; Oppenheim, Catherine

    2016-10-01

    Rapid and reliable assessment of the perfusion-weighted imaging (PWI)/diffusion-weighted imaging (DWI) mismatch is required to promote its wider application in both acute stroke clinical routine and trials. We tested whether an evaluation based on the Alberta Stroke Program Early CT Score (ASPECTS) reliably identifies the PWI/DWI mismatch. A total of 232 consecutive patients with acute middle cerebral artery stroke who underwent pretreatment magnetic resonance imaging (PWI and DWI) were retrospectively evaluated. PWI-ASPECTS and DWI-ASPECTS were determined blind from manually segmented PWI and DWI volumes. Mismatch-ASPECTS was defined as the difference between PWI-ASPECTS and DWI-ASPECTS (a high score indicates a large mismatch). We determined the mismatch-ASPECTS cutoff that best identified the volumetric mismatch, defined as VolumeTmax>6s/VolumeDWI≥1.8, a volume difference≥15 mL, and a VolumeDWImismatch-ASPECTS ≥2 best identified a volumetric mismatch, with a sensitivity of 0.93 (95% confidence interval, 0.89-0.98) and a specificity of 0.82 (95% confidence interval, 0.74-0.89). The mismatch-ASPECTS method can detect a true mismatch in patients with acute middle cerebral artery stroke. It could be used for rapid screening of patients with eligible mismatch, in centers not equipped with ultrafast postprocessing software. © 2016 American Heart Association, Inc.

  19. Validation of the spectral mismatch correction factor using an LED-based solar simulator

    DEFF Research Database (Denmark)

    Riedel, Nicholas; Santamaria Lancia, Adrian Alejo; Thorsteinsson, Sune

    -halide light sources provide. In this work we will use an EcoSun10L LED module tester from Ecoprogetti to perform short circuit current (ISC) measurements under various class A, B and C spectra. We will apply a spectral mismatch correction to the measured ISC under each test spectrum per IEC 60904-7. In all...... scenarios, a small area mono-Si cell is used the reference cell and a similar mono-Si cell is used as the PV device under test (DUT). Finally, we quantify the variation of the DUT’s measured and spectrally corrected Isc under the class A, B and C test spectra....

  20. Strong Optical Shock excitation in the mismatched regime of bubble plasma-wave based LWFA

    Science.gov (United States)

    Sahai, Aakash

    2017-10-01

    We present investigations into the excitation of a strong optical shock through slicing of a high intensity laser pulse driving a bubble plasma wave in a regime of mis-match between the incident laser waist-size and the bubble size ( = 2√{a0} c /ωpe). In the matched regime, it is well-known that over long timescales, the laser continuously undergoes differential frequency-shifts in different bubble phases, forming an optical shock. In the mis-matched regime, rapid laser waist and resulting bubble oscillations change the location of the peak laser ponderomotive force. This changes the location and the magnitude of the peak electron density interacting with the laser pulse. A sudden increase in the electron density during a laser radial squeeze event, slices the laser envelope longitudinally near its peak amplitude, exciting a strong optical shock state. This is shown to occur much earlier in laser evolution only over a narrow range of plasma densities where the imbalance between the longitudinal & radial ponderomotive forces excites elongated bubbles, injects ultra-low emittance electron beams and sustains ultra-high peak plasma fields. We acknowledge STFC Grants ST/J002062/1 and ST/P000835/1 for the John Adams Institute of Accelerator Science.

  1. Investigation of Nascent Base Pair and Polymerase Behavior in the Presence of Mismatches in DNA Polymerase I Using Molecular Dynamics.

    Science.gov (United States)

    Yeager, Andrew; Humphries, Kathryn; Farmer, Ellen; Cline, Gene; Miller, Bill R

    2018-02-26

    Optimizing DNA polymerases for a broad range of tasks requires an understanding of the factors influencing polymerase fidelity, but many details of polymerase behavior remain unknown, especially in the presence of mismatched nascent base pairs. Using molecular dynamics, the large fragment of Bacillus stearothermophilus DNA polymerase I is simulated in the presence of all 16 possible standard nucleoside triphosphate-template (dNTP-dN) pairs, including four Watson-Crick pairs and 12 mismatches. The precatalytic steps of nucleotide addition from nucleotide insertion to immediately preceding catalysis are explored using three starting structures representing different stages of nucleotide addition. From these simulations, interactions between dNTPs and the DNA-protein complex formed by the polymerase are elucidated. Patterns of large-scale conformational shifts, classification of nucleotide pairs based on composition, and investigation of the roles of residues interacting with dNTPs are completed on 50+ μs of simulation. The role of molecular dynamics in studies of polymerase behavior is discussed.

  2. Strategy in clinical practice for classification of unselected colorectal tumours based on mismatch repair deficiency

    DEFF Research Database (Denmark)

    Jensen, Lars Henrik; Lindebjerg, J; Byriel, L

    2007-01-01

    nonpolyposis colon cancer or Lynch syndrome), but most are epigenetic changes of sporadic origin. The aim of this study was to define a robust and inexpensive strategy for such classification in clinical practice. Method Tumours and blood samples from 262 successive patients with colorectal adenocarcinomas......Objective Deficiency of DNA mismatch repair (MMR) causes microsatellite instability (MSI) in a subset of colorectal cancers. Patients with these tumours have a better prognosis and may have an altered response to chemotherapy. Some of the tumours are caused by hereditary mutations (hereditary...... of molecular characteristics we found 223 patients with intact MMR, 35 patients with sporadic MMR deficiency, and four patients who were likely to have hereditary MMR deficiency. Conclusion To obtain the maximal benefit for patients and clinicians, MMR testing should be supplemented with MLH1 methylation...

  3. The plant virus microscope image registration method based on mismatches removing.

    Science.gov (United States)

    Wei, Lifang; Zhou, Shucheng; Dong, Heng; Mao, Qianzhuo; Lin, Jiaxiang; Chen, Riqing

    2016-01-01

    The electron microscopy is one of the major means to observe the virus. The view of virus microscope images is limited by making specimen and the size of the camera's view field. To solve this problem, the virus sample is produced into multi-slice for information fusion and image registration techniques are applied to obtain large field and whole sections. Image registration techniques have been developed in the past decades for increasing the camera's field of view. Nevertheless, these approaches typically work in batch mode and rely on motorized microscopes. Alternatively, the methods are conceived just to provide visually pleasant registration for high overlap ratio image sequence. This work presents a method for virus microscope image registration acquired with detailed visual information and subpixel accuracy, even when overlap ratio of image sequence is 10% or less. The method proposed focus on the correspondence set and interimage transformation. A mismatch removal strategy is proposed by the spatial consistency and the components of keypoint to enrich the correspondence set. And the translation model parameter as well as tonal inhomogeneities is corrected by the hierarchical estimation and model select. In the experiments performed, we tested different registration approaches and virus images, confirming that the translation model is not always stationary, despite the fact that the images of the sample come from the same sequence. The mismatch removal strategy makes building registration of virus microscope images at subpixel accuracy easier and optional parameters for building registration according to the hierarchical estimation and model select strategies make the proposed method high precision and reliable for low overlap ratio image sequence. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Visual Perfusion-Diffusion Mismatch Is Equivalent to Quantitative Mismatch

    Science.gov (United States)

    Luby, Marie; Ku, Katherine D.; Latour, Lawrence L.; Merino, José G.; Hsia, Amie W.; Lynch, John K.; Warach, Steven

    2011-01-01

    Background and Purpose The concept of stroke MRI mismatch based on qualitative evaluation of diffusion-weighted (DWI) and perfusion-weighted imaging (PWI) has been applied in clinical practice for several years. The benefit of MRI in providing pathological evidence of ischemia prior to thrombolytic treatment has been demonstrated. The purpose of this study is to determine the reliability of the qualitative method and compare it to quantitative mismatch measurement in thrombolytic treated patients. Methods Patients (n=70) were selected from the Lesion Evolution of Stroke and Ischemic On Neuroimaging (LESION) database if they: (1) were treated with intravenous (IV) rt-PA, (2) had a pre-treatment MRI with evaluable DWI and PWI, and (3) had acute ischemic lesion volume >10 ml on DWI as determined by core imaging lab measurements. Quantitative mismatch was defined as a difference of >50 ml between abnormal Mean Transit Time (MTT) and DWI volumes. Sample characteristics and post-discharge Modified Rankin Scale (mRS) for the positive mismatch patients were compared between the subgroups identified by qualitative versus quantitative methods. Results Patient characteristics and thrombolytic outcomes (sex, age, NIHSS, mismatch volume, and mRS) did not differ for mismatch patients identified by qualitative versus quantitative methods. Qualitative mismatch selection among neurologists had a high sensitivity (0.82), specificity (0.80), accuracy (0.81) and positive predictive value (0.88) compared to quantitative measurements. Conclusions We observed that qualitative evaluation of mismatch identified the same thrombolytic treated patients compared to retrospective quantitative mismatch measurements. PMID:21311057

  5. Microcomputer-based video motion detection system

    International Nuclear Information System (INIS)

    Howington, L.C.

    1979-01-01

    This system was developed to enhance the volumetric intrusion detection capability of the Oak Ridge Y-12 Plant's security program. Not only does the system exhibit an extended range of detection over present infrared, microwave, and ultrasonic devices, it also provides an instantaneous assessment capability by providing the operator with a closed-circuit television (CCTV) image of the alarm scene as soon as motion is detected. The system consists of a custom-built, microcomputer-based, video processor which analyzes the signals received from a network of video cameras. The operator can view the camera images as they are displayed on a CCTV monitor while alarm scenes are displayed on a second monitor. Motion is detected by digitizing and comparing successive video frames and making an alarm decision based on the degree of mismatch. The software-based nature of the microcomputer lends a great deal of flexibility and adaptability in making the alarm decision. Alarm decision variables which are easily adjusted through software are the percent change in gray level required to label a pixel (picture element) as suspect, the number of suspect pixels required to generate an alarm, the pixel pattern to be sampled from the image, and the rate at which a new reference frame is taken. The system is currently being evaluated in a warehouse for potential application in several areas of the Plant. This paper discusses the hardware and software design of the system as well as problems encountered in its implementation and results obtained

  6. Islanding detection scheme based on adaptive identifier signal estimation method.

    Science.gov (United States)

    Bakhshi, M; Noroozian, R; Gharehpetian, G B

    2017-11-01

    This paper proposes a novel, passive-based anti-islanding method for both inverter and synchronous machine-based distributed generation (DG) units. Unfortunately, when the active/reactive power mismatches are near to zero, majority of the passive anti-islanding methods cannot detect the islanding situation, correctly. This study introduces a new islanding detection method based on exponentially damped signal estimation method. The proposed method uses adaptive identifier method for estimating of the frequency deviation of the point of common coupling (PCC) link as a target signal that can detect the islanding condition with near-zero active power imbalance. Main advantage of the adaptive identifier method over other signal estimation methods is its small sampling window. In this paper, the adaptive identifier based islanding detection method introduces a new detection index entitled decision signal by estimating of oscillation frequency of the PCC frequency and can detect islanding conditions, properly. In islanding conditions, oscillations frequency of PCC frequency reach to zero, thus threshold setting for decision signal is not a tedious job. The non-islanding transient events, which can cause a significant deviation in the PCC frequency are considered in simulations. These events include different types of faults, load changes, capacitor bank switching, and motor starting. Further, for islanding events, the capability of the proposed islanding detection method is verified by near-to-zero active power mismatches. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  7. Development of Multiplex-Mismatch Amplification Mutation-PCR Assay for Simultaneous Detection of Campylobacter jejuni and Mutation in gyrA Gene Related to Fluoroquinolone Resistance.

    Science.gov (United States)

    Cui, Mingquan; Wu, Chenbin; Zhang, Peng; Wu, Congming

    2016-11-01

    Campylobacter jejuni, a foodborne pathogen, is the major cause of enteritis in humans worldwide, however, its increasing resistance to fluoroquinolones reported recently is of a major concern. In the present study, multiplex-mismatch amplification mutation assay-polymerase chain reaction (MMAMA-PCR) was developed for the first time with the aim to quickly identify C. jejuni and to detect the single nucleotide mutation (C-257 to T) frequently observed in gyrA gene, associated with the acquisition of resistance to fluoroquinolones. In this assay, mismatch amplification mutation primers for the detection of gyrA mutation in C. jejuni were coupled with primers for the hip gene encoding for hippuricase and 16S rRNA gene of C. jejuni, respectively, in the multiplex PCR assay. The specificity and accuracy of this method were analyzed by the use of 78 C. jejuni strains with previously confirmed resistance phenotypes and the mutation (C-257 to T) in gyrA gene, as well as 107 clinical isolates of various bacterial species, including 29 C. jejuni isolates. This study indicates that MMAMA-PCR is a promising assay for the rapid identification of C. jejuni with a specific mutation in gyrA gene, responsible for the resistance to fluoroquinolones.

  8. Rapid shear alignment of sub-10 nm cylinder-forming block copolymer films based on thermal expansion mismatch

    Science.gov (United States)

    Nicaise, Samuel M.; Gadelrab, Karim R.; G, Amir Tavakkoli K.; Ross, Caroline A.; Alexander-Katz, Alfredo; Berggren, Karl K.

    2018-01-01

    Directed self-assembly of block copolymers (BCPs) provided by shear-stress can produce aligned sub-10 nm structures over large areas for applications in integrated circuits, next-generation data storage, and plasmonic structures. In this work, we present a fast, versatile BCP shear-alignment process based on coefficient of thermal expansion mismatch of the BCP film, a rigid top coat and a substrate. Monolayer and bilayer cylindrical microdomains of poly(styrene-b-dimethylsiloxane) aligned preferentially in-plane and orthogonal to naturally-forming or engineered cracks in the top coat film, allowing for orientation control over 1 cm2 substrates. Annealing temperatures, up to 275 °C, provided low-defect alignment up to 2 mm away from cracks for rapid (thermal annealing was critical for the observed microdomain alignment.

  9. Rate based failure detection

    Science.gov (United States)

    Johnson, Brett Emery Trabun; Gamage, Thoshitha Thanushka; Bakken, David Edward

    2018-01-02

    This disclosure describes, in part, a system management component and failure detection component for use in a power grid data network to identify anomalies within the network and systematically adjust the quality of service of data published by publishers and subscribed to by subscribers within the network. In one implementation, subscribers may identify a desired data rate, a minimum acceptable data rate, desired latency, minimum acceptable latency and a priority for each subscription. The failure detection component may identify an anomaly within the network and a source of the anomaly. Based on the identified anomaly, data rates and or data paths may be adjusted in real-time to ensure that the power grid data network does not become overloaded and/or fail.

  10. Ventromedial prefrontal cortex drives hippocampal theta oscillations induced by mismatch computations.

    Science.gov (United States)

    Garrido, Marta I; Barnes, Gareth R; Kumaran, Dharshan; Maguire, Eleanor A; Dolan, Raymond J

    2015-10-15

    Detecting environmental change is fundamental for adaptive behavior in an uncertain world. Previous work indicates the hippocampus supports the generation of novelty signals via implementation of a match-mismatch detector that signals when an incoming sensory input violates expectations based on past experience. While existing work has emphasized the particular contribution of the hippocampus, here we ask which other brain structures also contribute to match-mismatch detection. Furthermore, we leverage the fine-grained temporal resolution of magnetoencephalography (MEG) to investigate whether mismatch computations are spectrally confined to the theta range, based on the prominence of this range of oscillations in models of hippocampal function. By recording MEG activity while human subjects perform a task that incorporates conditions of match-mismatch novelty we show that mismatch signals are confined to the theta band and are expressed in both the hippocampus and ventromedial prefrontal cortex (vmPFC). Effective connectivity analyses (dynamic causal modeling) show that the hippocampus and vmPFC work as a functional circuit during mismatch detection. Surprisingly, our results suggest that the vmPFC drives the hippocampus during the generation and processing of mismatch signals. Our findings provide new evidence that the hippocampal-vmPFC circuit is engaged during novelty processing, which has implications for emerging theories regarding the role of vmPFC in memory. Copyright © 2015. Published by Elsevier Inc.

  11. Enhanced DNA detection based on the amplification of gold nanoparticles using quartz crystal microbalance

    International Nuclear Information System (INIS)

    Nie, L B; Yang, Y; Li, S; He, N Y

    2007-01-01

    Gold nanoparticles were used as mass amplifiers to improve the frequency signal of QCM detection of DNA. Indirect labelling and direct labelling of DNA probes with gold nanoparticles was studied. Two-times amplification of gold nanoparticles was carried out to further improve the detection signal. It was suggested that the frequency shift of the indirect-labelling method was much more significant than that of the direct-labelling method. The detection limit of one-time amplification and two-times amplification detection of a 33-base oligonucleotide was 100 and 10 fM, respectively. Under corresponding sensitivity, the one-base mismatched DNA and complementary DNA could be distinguished clearly. As an example, the two-times amplification detection of 677TT gene type validated that the ratio of frequency shift for a complementary DNA: one-base-mismatched one was 2.1:1 under the detection limit of 10 fM

  12. Prognostic values of DNA mismatch repair genes in ovarian cancer patients treated with platinum-based chemotherapy.

    Science.gov (United States)

    Zhao, Chuchu; Li, Saisai; Zhao, Menghuang; Zhu, Haiyan; Zhu, Xueqiong

    2018-01-01

    DNA mismatch repair (MMR) is a highly conserved biological pathway that plays a key role in maintaining genomic stability. MMR has been reported as a prognostic marker in certain cancers; however, the results are controversial. Therefore, identification of the prognostic value of MMR genes in ovarian cancer based on a large sample size is pivotal. In the current study, we systemically investigated the prognostic roles of seven MMR genes, MSH2, MSH3, MSH6, MLH1, MLH3, PMS1 and PMS2, in ovarian cancer patients treated with platinum-based chemotherapy through "The Kaplan-Meier plotter" (KM plotter) database, which contains gene expression data and survival information of ovarian cancer patients. Among seven MMR genes, high mRNA levels of MSH6, MLH1 and PMS2 were significantly associated with a better overall survival for all ovarian cancer patients treated with platinum-based chemotherapy, especially in late-stage and poor-differentiated ovarian cancer patients. Increased MSH6 and PMS2 mRNA expression was correlated with a favorable overall survival in serous ovarian cancer patients. Our results indicate that sufficient MMR system is associated with an improved survival in ovarian cancer treated with platinum-based chemotherapy. MMR gene may be a potential prognosis predictor in ovarian cancer.

  13. Multi-domain feature selection in auditory MisMatch Negativity via PARAFAC-based template matching approach.

    Science.gov (United States)

    Pouryazdian, Saeed; Chang, Andrew; Bosnyak, Dan J; Trainor, Laurel J; Beheshti, Soosan; Krishnan, Sridhar

    2016-08-01

    MisMatch Negativity (MMN) is a small event-related potential (ERP) that provide an index of sensory learning and perceptual accuracy for the cognitive research. Group-level analysis plays an important role for detecting differences at group or condition level, especially when the signal-to-noise ratio is low. Tensor factorization has provided a framework for group-level analysis of ERPs by exploiting more information of brain responses in more domains simultaneously. A 4-way ERP tensor of time × frequency × channel × subjects/condition is generated and decomposed via PARAFAC. A crucial step after PARAFAC decomposition is to select the component that corresponds to the event of interest and moreover differentiates the two groups\\conditions. This is usually done manually, which is tedious when the number of components is high. Here we propose a technique to select the multi-domain feature of an ERP among all extracted features by a template matching approach, that uses the MMN temporal and spectral signatures. Following a statistical test, the selected feature significantly discriminated subjects for the two experimental conditions.

  14. Multidimensional Skill Mismatch

    OpenAIRE

    Guvenen, Fatih; Kuruscu, Burhanettin; Tanaka, Satoshi; Wiczer, David

    2015-01-01

    What determines the earnings of a worker relative to his peers in the same occupation? What makes a worker fail in one occupation but succeed in another? More broadly, what are the factors that determine the productivity of a worker-occupation match? In this paper, we propose an empirical measure of skill mismatch for a worker-occupation match, which sheds light on these questions. This measure is based on the discrepancy between the portfolio of skills required by an occupation and the portf...

  15. DNA Mismatch Repair

    Science.gov (United States)

    MARINUS, M. G.

    2014-01-01

    DNA mismatch repair functions to correct replication errors in newly synthesized DNA and to prevent recombination between related, but not identical (homeologous), DNA sequences. The mechanism of mismatch repair is best understood in Escherichia coli and is the main focus of this review. The early genetic studies of mismatch repair are described as a basis for the subsequent biochemical characterization of the system. The effects of mismatch repair on homologous and homeologous recombination are described. The relationship of mismatch repair to cell toxicity induced by various drugs is included. The VSP (Very Short Patch) repair system is described in detail. PMID:26442827

  16. Impact of lower- vs. upper-hemifield presentation on automatic colour-deviance detection: a visual mismatch negativity study.

    Science.gov (United States)

    Müller, Dagmar; Roeber, Urte; Winkler, István; Trujillo-Barreto, Nelson; Czigler, István; Schröger, Erich

    2012-09-07

    The automatic processing of deviances from the temporal context of the visual environment has become an important topic in visual cognitive sciences, which is often investigated using the visual mismatch negativity (vMMN). This event-related potential (ERP) component is elicited by an irregular stimulus (e.g., a red disc) presented in a series of stimuli (e.g., green discs) comprising a temporal regularity (e.g., colour repetition). We determined the influence of lower- vs. upper-hemifield presentation of the irregular stimulus on the vMMN while using whole-field stimulus displays controlling for sustained shifts in spatial attention. Deviances presented in the lower hemifield elicited a larger vMMN than the ones presented in the upper hemifield at a latency of 200-280ms. However, this asymmetry was preceded by deviance-related hemifield effects already emerging at an earlier latency (110-150ms), where upper-hemifield deviances elicited a positive potential but lower-hemifield deviances did not. With variable resolution electromagnetic tomography (VARETA) early deviance-related activity was localised to retinotopically organised regions of the visual cortex (BA 17/18) and vMMN-sources were localised to the middle/superior occipital gyrus, to higher areas along the temporal visual stream, but also to BA 17/18. We argue that the upper/lower-hemifield vMMN asymmetry relies at least partially on the hemifield-dependent differential sensitivity of early deviance-related activity generated in retinotopically organised regions of the visual cortex. However, a superior automatic processing of deviances presented in the lower visual hemifield may also contribute to the effect. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Automatic change detection in vision: Adaptation, memory mismatch, or both? II: Oddball and adaptation effects on event-related potentials.

    Science.gov (United States)

    Bodnár, Flóra; File, Domonkos; Sulykos, István; Kecskés-Kovács, Krisztina; Czigler, István

    2017-11-01

    In this study we compared the event-related potentials (ERPs) obtained in two different paradigms: a passive visual oddball paradigm and an adaptation paradigm. The aim of the study was to investigate the relation between the effects of activity decrease following an adaptor (stimulus-specific adaptation) and the effects of an infrequent stimulus within sequences of frequent ones. In Experiment 1, participants were presented with different line textures. The frequent (standard) and rare (deviant) texture elements differed in their orientation. In Experiment 2, windmill pattern stimuli were presented in which the number of vanes differentiated the deviant and standard stimuli. In Experiment 1 the ERP differences elicited between the oddball deviant and the standard were similar to the differences between the ERPs to the nonadapted and adapted stimuli in the adaptation paradigm. In both paradigms the differences appeared as a posterior negativity with the latency of 120-140 ms. This finding demonstrates that the representation of a sequential rule (successive presentation of the standard) and the violation of this rule are not necessary for deviancy effects to emerge. In Experiment 2 (windmill pattern), in the oddball paradigm the difference potentials appeared as a long-lasting negativity. In the adaptation condition, the later part of this negativity (after 200 ms) was absent. We identified the later part of the oddball difference potential as the genuine visual mismatch negativity-that is, an ERP correlate of sequence violations. The latencies of the difference potentials (deviant minus standard) and the endogenous components (P1 and N1) diverged; therefore, the adaptation of these particular ERP components cannot explain the deviancy effect. Accordingly, the sources contributing to the standard-versus-deviant modulations differed from those related to visual adaptation; that is, they generated distinct ERP components.

  18. [Utility of immunohistochemistry in detecting alterations of mismatch repair genes of DNA. A series of 48 cases of colorectal cancer].

    Science.gov (United States)

    Ziadi, Sonia; Gacem, Riath Ben; Haoues, Imen; Hachana, Mouhamed; Amara, Khaled; Trimeche, Mounir; Golli, Lamia; Mokni, Moncef; Korbi, Sadok

    2011-01-01

    Hereditary non-polyposis colorectal cancer (HNPCC) is associated in more than 95% to a germline mutation in the genes of the mismatch repair (MMR) of DNA. The aim of this study was to assess the utility of immunohistochemistry, a simple and fast technique, in the triage of families where HNPCC is suspected. Tumor samples included in this study were from patients with resection for colorectal cancer, examined in our laboratory between 2004 and 2007. For each case, a formalin-fixed paraffin-embedded tissue block containing tumor tissue and normal adjacent mucosa was selected. Tumor specimens were examined with immunohistochemistry for the presence of hMLH1, hMSH2, and hMSH6 proteins. Scoring of the tumor staining was performed without any knowledge of patients' family history. The loss of protein expression was noted in four patients among 48 cases tested: two cases with isolated loss of hMSH2, a case with isolated loss of hMSH6 and one case with combined loss of MSH2/MSH6. No case has shown a suppression of hMLH1 protein. Comparing the immunohistochemical results for clinical has revealed a clear correlation between loss of protein expression demonstrated by immunohistochemistry and clinical data. Indeed, three cases among the four who showed no expression of MMR proteins showed at least one clinical criterion predictive of HNPCC. In conclusion, our study support the potential utility of immunohistochemistry to identify a significant portion of colorectal tumors derived from germline mutation of MMR genes and can be used as an adjunct measure in the identification of HNPCC.

  19. Nonfluorescent denaturing HPLC-based primer-extension method for allele-specific expression: application to analysis of mismatch repair genes.

    Science.gov (United States)

    Aceto, Gitana M; De Lellis, Laura; Catalano, Teresa; Veschi, Serena; Radice, Paolo; Di Iorio, Angelo; Mariani-Costantini, Renato; Cama, Alessandro; Curia, Maria Cristina

    2009-09-01

    Altered germline expression of genes may represent a powerful marker of genetic or epigenetic predisposition to cancer or other diseases. We developed and validated a method of nonfluorescent primer extension that uses a single dideoxynucleotide and denaturing HPLC (DHPLC) to analyze the relative allele expression. We devised 5 independent assays for measuring allele-specific expression (ASE) to exploit different markers of mismatch repair genes MLH1 [mutL homolog 1, colon cancer, nonpolyposis type 2 (E. coli)] and MSH2 [mutS homolog 2, colon cancer, nonpolyposis type 1 (E. coli)]. We initially confirmed method reproducibility with genomic DNA (gDNA) from individuals heterozygous for a frequent single-nucleotide polymorphism in the MLH1 gene. After this preliminary validation with gDNA, we confirmed assay reproducibility with cDNA templates from control individuals. Relative allele expression was estimated by comparing the heights of the peaks corresponding to the 2 alleles. Results obtained with gDNA templates were used to normalize cDNA results. With these DHPLC-based primer-extension assays, we detected and confirmed a 5-fold imbalance in MLH1 allele expression in a mutation-negative patient with hereditary nonpolyposis colorectal cancer and in another patient with a modest degree of imbalance in MLH1 expression. Among control individuals, the relative expression of MLH1 alleles displayed a narrow range of variation. Independent DHPLC-based primer-extension assays for measuring and confirming ASE can be developed for different sequence variants of interest. This DHPLC application provides a cost-effective method for detecting ASE in cases for which conventional screening fails to detect pathogenic mutations in candidate genes and may be applicable for confirming ASE revealed by other methods, such as those used for transcriptome-wide analyses. .

  20. [Impact of HLA mismatch on transplant outcomes].

    Science.gov (United States)

    Kanda, Junya

    Human leukocyte antigen (HLA) mismatch increases the risk of severe graft-versus-host disease (GVHD) and transplant-related mortality. However, the variety of stem cell sources such as cord blood units or the improvements in GVHD prophylaxis makes the interpretation of HLA mismatch more complex. In unrelated transplantation, the locus of HLA mismatch has a great impact on the donor candidate selection, whereas in related transplantation, it has an impact on the intensity of GVHD prophylaxis because donor availability is limited. Anti-thymocyte globulin and post-transplant cyclophosphamide are attractive GVHD prophylactic agents to reduce the risk of immune-associated complications in HLA-mismatched transplantations. HLA mismatch has a reduced impact in adult cord blood transplantation. In this review article, the impact of HLA mismatch based on graft sources is discussed.

  1. Single molecule Studies of DNA Mismatch Repair

    Science.gov (United States)

    Erie, Dorothy A.; Weninger, Keith R.

    2015-01-01

    DNA mismatch repair involves is a widely conserved set of proteins that is essential to limit genetic drift in all organisms. The same system of proteins plays key roles in many cancer related cellular transactions in humans. Although the basic process has been reconstituted in vitro using purified components, many fundamental aspects of DNA mismatch repair remain hidden due in part to the complexity and transient nature of the interactions between the mismatch repair proteins and DNA substrates. Single molecule methods offer the capability to uncover these transient but complex interactions and allow novel insights into mechanisms that underlie DNA mismatch repair. In this review, we discuss applications of single molecule methodology including electron microscopy, atomic force microscopy, particle tracking, FRET, and optical trapping to studies of DNA mismatch repair. These studies have led to formulation of mechanistic models of how proteins identify single base mismatches in the vast background of matched DNA and signal for their repair. PMID:24746644

  2. Detecting scale violations in absence of mismatch requires music-syntactic analysis: a further look at the early right anterior negativity (ERAN).

    Science.gov (United States)

    Kalda, Tiina; Minati, Ludovico

    2012-07-01

    The purpose of this study was to determine whether infrequent scale violations in a sequence of in-key notes are detected when the deviants are matched for frequency of occurrence and preceding intervals with the control notes. We further investigated whether the detectability of scale violations is modulated by the presence of melodic context and by the level of musical training. Event related potentials were recorded from 14 musicians and 13 non-musicians. In non-musicians, the out-of-key notes elicited an early right anterior negativity (ERAN), which appeared prominently over right frontal sites only when presented within structured sequences; no effects were found when the out-of-key notes were presented within scrambled sequences. In musicians, the out-of-key notes elicited a similar bilateral ERAN in structured and scrambled sequences. Our findings suggest that scale information is processed at the level of music-syntactic analysis, and that the detection of deviants does not require activation of auditory sensory memory by mismatch effects. Scales are perceived as a broader context, not just as online interval relations. Additional melodic context information appears necessary to support the representation of scale deviants in non-musicians, but not in musically-trained individuals, likely as a consequence of stronger pre-existing representations.

  3. Visual, base-specific detection of nucleic acid hybridization using polymerization-based amplification.

    Science.gov (United States)

    Hansen, Ryan R; Johnson, Leah M; Bowman, Christopher N

    2009-03-15

    Polymerization-based signal amplification offers sensitive visualization of biotinylated biomolecules functionalized to glass microarrays in a manner suitable for point-of-care use. Here we report using this method for visual detection of multiplexed nucleic acid hybridizations from complex media and develop an application toward point mutation detection and single nucleotide polymorphism (SNP) typing. Primer extension reactions were employed to label selectively and universally all complementary surface DNA hybrids with photoinitiators, permitting simultaneous and dynamic photopolymerization from positive sites to 0.5-nM target concentrations. Dramatic improvements in signal ratios between complementary and mismatched hybrids enabled visual discrimination of single base differences in KRAS codon-12 biomarkers.

  4. A Novel Teaching-Learning-Based Optimization for Improved Mutagenic Primer Design in Mismatch PCR-RFLP SNP Genotyping.

    Science.gov (United States)

    Cheng, Yu-Huei

    2016-01-01

    Many single nucleotide polymorphisms (SNPs) for complex genetic diseases are genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in small-scale basic research studies. It is an essential work to design feasible PCR-RFLP primer pair and find out available restriction enzymes to recognize the target SNP for PCR experiments. However, many SNPs are incapable of performing PCR-RFLP makes SNP genotyping become unpractical. A genetic algorithm (GA) had been proposed for designing mutagenic primer and get available restriction enzymes, but it gives an unrefined solution in mutagenic primers. In order to improve the mutagenic primer design, we propose TLBOMPD (TLBO-based Mutagenic Primer Design) a novel computational intelligence-based method that uses the notion of "teaching and learning" to search for more feasible mutagenic primers and provide the latest available restriction enzymes. The original Wallace's formula for the calculation of melting temperature is maintained, and more accurate calculation formulas of GC-based melting temperature and thermodynamic melting temperature are introduced into the proposed method. Mutagenic matrix is also reserved to increase the efficiency of judging a hypothetical mutagenic primer if involve available restriction enzymes for recognizing the target SNP. Furthermore, the core of SNP-RFLPing version 2 is used to enhance the mining work for restriction enzymes based on the latest REBASE. Twenty-five SNPs with mismatch PCR-RFLP screened from 288 SNPs in human SLC6A4 gene are used to appraise the TLBOMPD. Also, the computational results are compared with those of the GAMPD. In the future, the usage of the mutagenic primers in the wet lab needs to been validated carefully to increase the reliability of the method. The TLBOMPD is implemented in JAVA and it is freely available at http://tlbompd.googlecode.com/.

  5. DNA mismatch repair MSH2 gene-based SNP associated with different populations.

    Science.gov (United States)

    Abduljaleel, Zainularifeen; Al-Allaf, Faisal A; Khan, Wajahatullah; Athar, Mohammad; Shahzad, Naiyer; Taher, Mohiuddin M; Alanazi, Mohammed; Elrobh, Mohamed; Reddy, Narasimha P

    2014-06-01

    We screened for the major essential single-nucleotide polymorphism (SNP) variant that might be associated with the MSH2 gene based on the data available from three types of human tissue samples [156 lymphoblastoid cell variations (LCL), 160 epidermis, 166 fat]. An association analysis confirmed that the KCNK12 SNP variant (rs748780) was highly associated (p value 9 × 10(-4)) with the MSH2 gene for all three samples. Using SNP identification, we further found that the recognized SNP was also relevant among Hapmap populations. Techniques that display specific SNPs associated with the gene of interest or nearby genes provide more reliable genetic associations than techniques that rely on data from individual SNPs. We investigated the MSH2 gene regional linkage association with the determined SNP (rs748780), KCNK12 variant (Allele T>C) in the intronic region, in HapMap3 full dataset populations, Yoruba in Ibadan, Nigeria (YRI), Utah residents with ancestry from northern Europe (CEU), Han Chinese in Beijing, China (CHB), and a population of Mexican ancestry in Los Angeles, California (MEX). A gene-based SNP association analysis analyzes the combined impact of every variant within the gene while creating referrals to linkage disequilibrium or connections between markers. Our results indicated that among the four populations studied, this association was highest in the MEX population based on the r(2) value; a similar pattern was also observed in the other three populations. The relevant SNP rs748780 in KCNK12 is related to a superfamily of potassium channel pore-forming P-domain proteins as well as to other non-pore-forming proteins and has been shown to be relevant to neurological disorder predisposition in MEX as well as in other populations.

  6. An Analysis of Skill Mismatch Using Direct Measures of Skills

    OpenAIRE

    Desjardins, R

    2011-01-01

    The focus of this study is on the potential causes of skill mismatch, the extent of skill mismatch, the sociodemographic make-up of skill mismatch, and the consequences of skill mismatch in terms of earnings as well as employer sponsored adult education/training. A distinction is made between skill mismatch and education mismatch. The analysis is based on the 2003-2007 Adult Literacy and Lifeskills Survey (ALLS) – a dataset similar to the one that is forthcoming from the Programme for Interna...

  7. Detection and quantitation of single nucleotide polymorphisms, DNA sequence variations, DNA mutations, DNA damage and DNA mismatches

    Science.gov (United States)

    McCutchen-Maloney, Sandra L.

    2002-01-01

    DNA mutation binding proteins alone and as chimeric proteins with nucleases are used with solid supports to detect DNA sequence variations, DNA mutations and single nucleotide polymorphisms. The solid supports may be flow cytometry beads, DNA chips, glass slides or DNA dips sticks. DNA molecules are coupled to solid supports to form DNA-support complexes. Labeled DNA is used with unlabeled DNA mutation binding proteins such at TthMutS to detect DNA sequence variations, DNA mutations and single nucleotide length polymorphisms by binding which gives an increase in signal. Unlabeled DNA is utilized with labeled chimeras to detect DNA sequence variations, DNA mutations and single nucleotide length polymorphisms by nuclease activity of the chimera which gives a decrease in signal.

  8. Dissociated roles of the inferior frontal gyrus and superior temporal sulcus in audiovisual processing: top-down and bottom-up mismatch detection.

    Directory of Open Access Journals (Sweden)

    Takeshi Uno

    Full Text Available Visual inputs can distort auditory perception, and accurate auditory processing requires the ability to detect and ignore visual input that is simultaneous and incongruent with auditory information. However, the neural basis of this auditory selection from audiovisual information is unknown, whereas integration process of audiovisual inputs is intensively researched. Here, we tested the hypothesis that the inferior frontal gyrus (IFG and superior temporal sulcus (STS are involved in top-down and bottom-up processing, respectively, of target auditory information from audiovisual inputs. We recorded high gamma activity (HGA, which is associated with neuronal firing in local brain regions, using electrocorticography while patients with epilepsy judged the syllable spoken by a voice while looking at a voice-congruent or -incongruent lip movement from the speaker. The STS exhibited stronger HGA if the patient was presented with information of large audiovisual incongruence than of small incongruence, especially if the auditory information was correctly identified. On the other hand, the IFG exhibited stronger HGA in trials with small audiovisual incongruence when patients correctly perceived the auditory information than when patients incorrectly perceived the auditory information due to the mismatched visual information. These results indicate that the IFG and STS have dissociated roles in selective auditory processing, and suggest that the neural basis of selective auditory processing changes dynamically in accordance with the degree of incongruity between auditory and visual information.

  9. Dissociated roles of the inferior frontal gyrus and superior temporal sulcus in audiovisual processing: top-down and bottom-up mismatch detection.

    Science.gov (United States)

    Uno, Takeshi; Kawai, Kensuke; Sakai, Katsuyuki; Wakebe, Toshihiro; Ibaraki, Takuya; Kunii, Naoto; Matsuo, Takeshi; Saito, Nobuhito

    2015-01-01

    Visual inputs can distort auditory perception, and accurate auditory processing requires the ability to detect and ignore visual input that is simultaneous and incongruent with auditory information. However, the neural basis of this auditory selection from audiovisual information is unknown, whereas integration process of audiovisual inputs is intensively researched. Here, we tested the hypothesis that the inferior frontal gyrus (IFG) and superior temporal sulcus (STS) are involved in top-down and bottom-up processing, respectively, of target auditory information from audiovisual inputs. We recorded high gamma activity (HGA), which is associated with neuronal firing in local brain regions, using electrocorticography while patients with epilepsy judged the syllable spoken by a voice while looking at a voice-congruent or -incongruent lip movement from the speaker. The STS exhibited stronger HGA if the patient was presented with information of large audiovisual incongruence than of small incongruence, especially if the auditory information was correctly identified. On the other hand, the IFG exhibited stronger HGA in trials with small audiovisual incongruence when patients correctly perceived the auditory information than when patients incorrectly perceived the auditory information due to the mismatched visual information. These results indicate that the IFG and STS have dissociated roles in selective auditory processing, and suggest that the neural basis of selective auditory processing changes dynamically in accordance with the degree of incongruity between auditory and visual information.

  10. Native and non-native speech sound processing and the neural mismatch responses: A longitudinal study on classroom-based foreign language learning.

    Science.gov (United States)

    Jost, Lea B; Eberhard-Moscicka, Aleksandra K; Pleisch, Georgette; Heusser, Veronica; Brandeis, Daniel; Zevin, Jason D; Maurer, Urs

    2015-06-01

    Learning a foreign language in a natural immersion context with high exposure to the new language has been shown to change the way speech sounds of that language are processed at the neural level. It remains unclear, however, to what extent this is also the case for classroom-based foreign language learning, particularly in children. To this end, we presented a mismatch negativity (MMN) experiment during EEG recordings as part of a longitudinal developmental study: 38 monolingual (Swiss-) German speaking children (7.5 years) were tested shortly before they started to learn English at school and followed up one year later. Moreover, 22 (Swiss-) German adults were recorded. Instead of the originally found positive mismatch response in children, an MMN emerged when applying a high-pass filter of 3 Hz. The overlap of a slow-wave positivity with the MMN indicates that two concurrent mismatch processes were elicited in children. The children's MMN in response to the non-native speech contrast was smaller compared to the native speech contrast irrespective of foreign language learning, suggesting that no additional neural resources were committed to processing the foreign language speech sound after one year of classroom-based learning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Educational Mismatch and Retirement

    Science.gov (United States)

    Bender, Keith A.; Heywood, John S.

    2017-01-01

    Using a panel data set of scientists in the US, we examine the hypothesis that workers in jobs poorly matched to their education are more likely to retire. In pooled estimates, we confirm that the mismatched are more likely to retire and that among retirees, the mismatched retire at younger ages. Hazard function estimates also support the…

  12. Domain Adaptation for Pedestrian Detection Based on Prediction Consistency

    Directory of Open Access Journals (Sweden)

    Yu Li-ping

    2014-01-01

    Full Text Available Pedestrian detection is an active area of research in computer vision. It remains a quite challenging problem in many applications where many factors cause a mismatch between source dataset used to train the pedestrian detector and samples in the target scene. In this paper, we propose a novel domain adaptation model for merging plentiful source domain samples with scared target domain samples to create a scene-specific pedestrian detector that performs as well as rich target domain simples are present. Our approach combines the boosting-based learning algorithm with an entropy-based transferability, which is derived from the prediction consistency with the source classifications, to selectively choose the samples showing positive transferability in source domains to the target domain. Experimental results show that our approach can improve the detection rate, especially with the insufficient labeled data in target scene.

  13. Artificial mismatch hybridization

    Science.gov (United States)

    Guo, Zhen; Smith, Lloyd M.

    1998-01-01

    An improved nucleic acid hybridization process is provided which employs a modified oligonucleotide and improves the ability to discriminate a control nucleic acid target from a variant nucleic acid target containing a sequence variation. The modified probe contains at least one artificial mismatch relative to the control nucleic acid target in addition to any mismatch(es) arising from the sequence variation. The invention has direct and advantageous application to numerous existing hybridization methods, including, applications that employ, for example, the Polymerase Chain Reaction, allele-specific nucleic acid sequencing methods, and diagnostic hybridization methods.

  14. Potential for DNA-based identification of Great Lakes fauna: Match and mismatch between taxa inventories and DNA barcode libraries

    Science.gov (United States)

    DNA-based identification of mixed-organism samples offers the potential to greatly reduce the need for resource-intensive morphological identification, which would be of value both to biotic condition assessment and non-native species early-detection monitoring. However, the abi...

  15. Detecting deletions, insertions, and single nucleotide substitutions in cloned β-globin genes and new polymorphic nucleotide substitutions in β-globin genes in a Japanese population using ribonuclease cleavage at mismatches in RNA: DNA duplexes

    International Nuclear Information System (INIS)

    Hiyama, Keiko; Kodaira, Mieko; Satoh, Chiyoko.

    1990-08-01

    The applicability of ribonuclease (RNase) cleavage at mismatches in RNA:DNA duplexes (the RNase cleavage method) for determining nucleotide variant rates was examined in a Japanese population. DNA segments of various lengths obtained from four different regions of one normal and three thalassemic cloned human β-globin genes were inserted into transcription vectors. Sense and antisense RNA probes uniformly labeled with 32 P were prepared. When RNA probes of 771 nucleotides (nt) or less were hybridized with cloned DNAs and the resulting duplexes were treated with a mixture of RNases A and T1, the length of products agreed with theoretical values. Twelve possible mismatches were examined. Since both sense and antisense probes were used, uncleavable mismatches such as G:T and G:G which were made from one combination of RNA and DNA strands could be converted to the cleavable C:A and C:C mismatches, respectively, by using the opposite combination. Deletions and insertions of one (G), four(TTCT), five (ATTTT), and 10 (ATTTTATTTT) nt were easily detected. A polymorphic substitution of T to C at position 666 of the second intervening sequence (IVS2-666) of the β-globin gene was detected using genomic DNAs from cell lines established from the peripheral B lymphocytes of 59 unrelated Japanese from Hiroshima or those amplified by polymerase chain reaction (PCR). The frequency of the gene with C at the IVS2-666 (allele C) was 0.48 and that of the gene with T (allene T) was 0.52. Two new polymorphic substitutions of C to A and A to T were detected at nucleotide positions 1789 and 1945 from the capping site, respectively, using genomic DNAs amplified by PCR. We conclude that it would be feasible to use the RNase cleavage method combined with PCR for large-scale screening of variation in chromosomal DNA. (J.P.N.)

  16. Nonoverlapping Blocks Based Copy-Move Forgery Detection

    Directory of Open Access Journals (Sweden)

    Yu Sun

    2018-01-01

    Full Text Available In order to solve the problem of high computational complexity in block-based methods for copy-move forgery detection, we divide image into texture part and smooth part to deal with them separately. Keypoints are extracted and matched in texture regions. Instead of using all the overlapping blocks, we use nonoverlapping blocks as candidates in smooth regions. Clustering blocks with similar color into a group can be regarded as a preprocessing operation. To avoid mismatching due to misalignment, we update candidate blocks by registration before projecting them into hash space. In this way, we can reduce computational complexity and improve the accuracy of matching at the same time. Experimental results show that the proposed method achieves better performance via comparing with the state-of-the-art copy-move forgery detection algorithms and exhibits robustness against JPEG compression, rotation, and scaling.

  17. A Mismatch EndoNuclease Array-Based Methodology (MENA for Identifying Known SNPs or Novel Point Mutations

    Directory of Open Access Journals (Sweden)

    Josep M. Comeron

    2016-04-01

    Full Text Available Accurate and rapid identification or confirmation of single nucleotide polymorphisms (SNPs, point mutations and other human genomic variation facilitates understanding the genetic basis of disease. We have developed a new methodology (called MENA (Mismatch EndoNuclease Array pairing DNA mismatch endonuclease enzymology with tiling microarray hybridization in order to genotype both known point mutations (such as SNPs as well as identify previously undiscovered point mutations and small indels. We show that our assay can rapidly genotype known SNPs in a human genomic DNA sample with 99% accuracy, in addition to identifying novel point mutations and small indels with a false discovery rate as low as 10%. Our technology provides a platform for a variety of applications, including: (1 genotyping known SNPs as well as confirming newly discovered SNPs from whole genome sequencing analyses; (2 identifying novel point mutations and indels in any genomic region from any organism for which genome sequence information is available; and (3 screening panels of genes associated with particular diseases and disorders in patient samples to identify causative mutations. As a proof of principle for using MENA to discover novel mutations, we report identification of a novel allele of the beethoven (btv gene in Drosophila, which encodes a ciliary cytoplasmic dynein motor protein important for auditory mechanosensation.

  18. A Mismatch EndoNuclease Array-Based Methodology (MENA) for Identifying Known SNPs or Novel Point Mutations.

    Science.gov (United States)

    Comeron, Josep M; Reed, Jordan; Christie, Matthew; Jacobs, Julia S; Dierdorff, Jason; Eberl, Daniel F; Manak, J Robert

    2016-04-05

    Accurate and rapid identification or confirmation of single nucleotide polymorphisms (SNPs), point mutations and other human genomic variation facilitates understanding the genetic basis of disease. We have developed a new methodology (called MENA (Mismatch EndoNuclease Array)) pairing DNA mismatch endonuclease enzymology with tiling microarray hybridization in order to genotype both known point mutations (such as SNPs) as well as identify previously undiscovered point mutations and small indels. We show that our assay can rapidly genotype known SNPs in a human genomic DNA sample with 99% accuracy, in addition to identifying novel point mutations and small indels with a false discovery rate as low as 10%. Our technology provides a platform for a variety of applications, including: (1) genotyping known SNPs as well as confirming newly discovered SNPs from whole genome sequencing analyses; (2) identifying novel point mutations and indels in any genomic region from any organism for which genome sequence information is available; and (3) screening panels of genes associated with particular diseases and disorders in patient samples to identify causative mutations. As a proof of principle for using MENA to discover novel mutations, we report identification of a novel allele of the beethoven (btv) gene in Drosophila, which encodes a ciliary cytoplasmic dynein motor protein important for auditory mechanosensation.

  19. Matching/Mismatching in Web-Based Learning: A Perspective Based on Cognitive Styles and Physiological Factors

    Science.gov (United States)

    Huang, Yueh-Min; Hwang, Jan-Pan; Chen, Sherry Y.

    2016-01-01

    Cognitive styles have been regarded as a crucial factor that affects the effectiveness of web-based learning (WBL). Previous research indicated that educational settings that match with students' cognitive styles can enhance students' learning performance, which is, however, linked to their emotion. Various physiological signals can be applied to…

  20. Single-molecule motions and interactions in live cells reveal target search dynamics in mismatch repair.

    Science.gov (United States)

    Liao, Yi; Schroeder, Jeremy W; Gao, Burke; Simmons, Lyle A; Biteen, Julie S

    2015-12-15

    MutS is responsible for initiating the correction of DNA replication errors. To understand how MutS searches for and identifies rare base-pair mismatches, we characterized the dynamic movement of MutS and the replisome in real time using superresolution microscopy and single-molecule tracking in living cells. We report that MutS dynamics are heterogeneous in cells, with one MutS population exploring the nucleoid rapidly, while another MutS population moves to and transiently dwells at the replisome region, even in the absence of appreciable mismatch formation. Analysis of MutS motion shows that the speed of MutS is correlated with its separation distance from the replisome and that MutS motion slows when it enters the replisome region. We also show that mismatch detection increases MutS speed, supporting the model for MutS sliding clamp formation after mismatch recognition. Using variants of MutS and the replication processivity clamp to impair mismatch repair, we find that MutS dynamically moves to and from the replisome before mismatch binding to scan for errors. Furthermore, a block to DNA synthesis shows that MutS is only capable of binding mismatches near the replisome. It is well-established that MutS engages in an ATPase cycle, which is necessary for signaling downstream events. We show that a variant of MutS with a nucleotide binding defect is no longer capable of dynamic movement to and from the replisome, showing that proper nucleotide binding is critical for MutS to localize to the replisome in vivo. Our results provide mechanistic insight into the trafficking and movement of MutS in live cells as it searches for mismatches.

  1. Optimisation of the CT h4S bioassay for detection of human interleukin-4 secreted by mononuclear cells stimulated by phytohaemaglutinin or by human leukocyte antigen mismatched mixed lymphocyte culture

    DEFF Research Database (Denmark)

    Petersen, Søren Lykke; Russell, Charlotte Astrid; Bendtzen, Klaus

    2002-01-01

    high anti-recipient IL-4 producing HTLp frequencies have been reported and associated with a decreased risk of GVHD. The aim of the present study was to define the optimal conditions for combined determination of IL-2 and IL-4 producing anti-recipient HTLp frequencies. We have optimised the CT.h4S......S bioassay detects 5 pg/ml of human recombinant IL-4 with no detection of IL-2 in concentrations below 500 pg/ml. We have found 72 h of culture optimal for detection of IL-2 and IL-4 produced by human mononuclear cells (MNC) in response to stimulation with phytohaemaglutinin and for detection of IL......-2 in human leukocyte antigen (HLA)-mismatched mixed leukocyte culture (MLC). An interindividual variation in cytokine accumulation was demonstrated for IL-4 but not for IL-2. With the use of 5x10(4) responder cells/well no IL-4 could be detected in HLA-mismatched MLC between days 1 and 16. The lack...

  2. Diagnosis of Constitutional Mismatch Repair-Deficiency Syndrome Based on Microsatellite Instability and Lymphocyte Tolerance to Methylating Agents

    DEFF Research Database (Denmark)

    Bodo, Sahra; Colas, Chrystelle; Buhard, Olivier

    2015-01-01

    BACKGROUND & AIMS: Patients with bi-allelic germline mutations in mismatch repair (MMR) genes (MLH1, MSH2, MSH6, or PMS2) develop a rare but severe variant of Lynch syndrome called constitutional MMR deficiency (CMMRD). This syndrome is characterized by early-onset colorectal cancers, lymphomas...... or leukemias, and brain tumors. There is no satisfactory method for diagnosis of CMMRD because screens for mutations in MMR genes are noninformative for 30% of patients. MMR-deficient cancer cells are resistant to genotoxic agents and have microsatellite instability (MSI), due to accumulation of errors...... in repetitive DNA sequences. We investigated whether these features could be used to identify patients with CMMRD. METHODS: We examined MSI by PCR analysis and tolerance to methylating or thiopurine agents (functional characteristics of MMR-deficient tumor cells) in lymphoblastoid cells (LCs) from 3 patients...

  3. Mismatch discrimination in fluorescent in situ hybridization using different types of nucleic acids

    DEFF Research Database (Denmark)

    Fontenete, Sílvia; Joana, Barros; Pedro, Madureira

    2015-01-01

    of different chemical modifications in fluorescent probes on their ability to successfully detect the complementary target and discriminate the mismatched base pairs by FISH. To our knowledge, this paper presents the first study where this analysis is performed with different types of FISH probes directly...

  4. A methodological contribution to measuring skill (mis)match

    OpenAIRE

    Sgobbi, F.; Suleman, F.

    2013-01-01

    WOS:000318029100011 (Nº de Acesso Web of Science) Researchers have long expressed their discontent with the existing measures of skill mismatch. This paper argues that traditional measures cannot fully capture the essence of an inherently multidimensional and job-specific concept such as skill mismatch. An empirical job-based methodology is proposed that classifies the types of skill (mis)matches based on performance of core skills and supplementary skills. The proposed methodology is test...

  5. The Eukaryotic Mismatch Recognition Complexes Track with the Replisome during DNA Synthesis.

    Science.gov (United States)

    Haye, Joanna E; Gammie, Alison E

    2015-12-01

    During replication, mismatch repair proteins recognize and repair mispaired bases that escape the proofreading activity of DNA polymerase. In this work, we tested the model that the eukaryotic mismatch recognition complex tracks with the advancing replisome. Using yeast, we examined the dynamics during replication of the leading strand polymerase Polε using Pol2 and the eukaryotic mismatch recognition complex using Msh2, the invariant protein involved in mismatch recognition. Specifically, we synchronized cells and processed samples using chromatin immunoprecipitation combined with custom DNA tiling arrays (ChIP-chip). The Polε signal was not detectable in G1, but was observed at active origins and replicating DNA throughout S-phase. The Polε signal provided the resolution to track origin firing timing and efficiencies as well as replisome progression rates. By detecting Polε and Msh2 dynamics within the same strain, we established that the mismatch recognition complex binds origins and spreads to adjacent regions with the replisome. In mismatch repair defective PCNA mutants, we observed that Msh2 binds to regions of replicating DNA, but the distribution and dynamics are altered, suggesting that PCNA is not the sole determinant for the mismatch recognition complex association with replicating regions, but may influence the dynamics of movement. Using biochemical and genomic methods, we provide evidence that both MutS complexes are in the vicinity of the replisome to efficiently repair the entire spectrum of mutations during replication. Our data supports the model that the proximity of MutSα/β to the replisome for the efficient repair of the newly synthesized strand before chromatin reassembles.

  6. Thermodynamic and structural properties of the specific binding between Ag⁺ ion and C:C mismatched base pair in duplex DNA to form C-Ag-C metal-mediated base pair.

    Science.gov (United States)

    Torigoe, Hidetaka; Okamoto, Itaru; Dairaku, Takenori; Tanaka, Yoshiyuki; Ono, Akira; Kozasa, Tetsuo

    2012-11-01

    Metal ion-nucleic acid interactions have attracted considerable interest for their involvement in structure formation and catalytic activity of nucleic acids. Although interactions between metal ion and mismatched base pair duplex are important to understand mechanism of gene mutations related to heavy metal ions, they have not been well-characterized. We recently found that the Ag(+) ion stabilized a C:C mismatched base pair duplex DNA. A C-Ag-C metal-mediated base pair was supposed to be formed by the binding between the Ag(+) ion and the C:C mismatched base pair to stabilize the duplex. Here, we examined specificity, thermodynamics and structure of possible C-Ag-C metal-mediated base pair. UV melting indicated that only the duplex with the C:C mismatched base pair, and not of the duplexes with the perfectly matched and other mismatched base pairs, was specifically stabilized on adding the Ag(+) ion. Isothermal titration calorimetry demonstrated that the Ag(+) ion specifically bound with the C:C base pair at 1:1 molar ratio with a binding constant of 10(6) M(-1), which was significantly larger than those for nonspecific metal ion-DNA interactions. Electrospray ionization mass spectrometry also supported the specific 1:1 binding between the Ag(+) ion and the C:C base pair. Circular dichroism spectroscopy and NMR revealed that the Ag(+) ion may bind with the N3 positions of the C:C base pair without distorting the higher-order structure of the duplex. We conclude that the specific formation of C-Ag-C base pair with large binding affinity would provide a binding mode of metal ion-DNA interactions, similar to that of the previously reported T-Hg-T base pair. The C-Ag-C base pair may be useful not only for understanding of molecular mechanism of gene mutations related to heavy metal ions but also for wide variety of potential applications of metal-mediated base pairs in various fields, such as material, life and environmental sciences. Copyright © 2012 Elsevier

  7. Imagery mismatch negativity in musicians.

    Science.gov (United States)

    Herholz, Sibylle C; Lappe, Claudia; Knief, Arne; Pantev, Christo

    2009-07-01

    The present study investigated musical imagery in musicians and nonmusicians by means of magnetoencephalography (MEG). We used a new paradigm in which subjects had to continue familiar melodies in their mind and then judged if a further presented tone was a correct continuation of the melody. Incorrect tones elicited an imagery mismatch negativity (iMMN) in musicians but not in nonmusicians. This finding suggests that the MMN component can be based on an imagined instead of a sensory memory trace and that imagery of music is modulated by musical expertise.

  8. Challenges in assessing pathogenicity based on frequency of variants in mismatch repair genes: an extreme case of a MSH2 variant and a meta-analysis.

    Science.gov (United States)

    Woo, Hye In; Woo, Young Min; Kim, Sollip; Lee, Seung-Tae; Ki, Chang-Seok; Kim, Jong-Won

    2014-08-10

    The clinical interpretation of variants in mismatch repair (MMR) genes associated with Lynch syndrome can be confusing when the functional nature of the variant is not clearly defined. We report an extreme case where a polymorphism in the MSH2 gene which had a low minor allele frequency, was misclassified as a mutation based on low evidential methods in the database and previous publications. We expanded this experience to perform a systematic meta-analysis in order to investigate other variants that have potentially been misclassified. Our results suggested that the interpretation of pathogenicity should be more cautious and emphasized the need for solid validation through multiple analyses including functional analysis for variants in MMR genes. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Ovarian cancer at young age: the contribution of mismatch-repair defects in a population-based series of epithelial ovarian

    DEFF Research Database (Denmark)

    Domanska, K; Malander, S; Måsbäck, A

    2007-01-01

    At least one of ten patients with ovarian cancer is estimated to develop their tumor because of heredity with the breast and ovarian cancer syndrome due to mutations in the BRCA1 and BRCA2 genes and hereditary nonpolyposis colorectal cancer (HNPCC) being the major genetic causes. Cancer at young...... age is a hallmark of heredity, and ovarian cancers associated with HNPCC have been demonstrated to develop at a particularly early age. We used the Swedish Cancer Registry to identify a population-based series of 98 invasive epithelial ovarian cancers that developed before 40 years. Mucinous...... and endometrioid cancers were overrepresented and were diagnosed in 27% and 16% of the tumors, respectively. Immunostaining using antibodies against MLH1, PMS2, MSH2, and MSH6 was used to assess the mismatch-repair status and revealed loss of expression of MLH1/PMS2 in two cases, loss of MSH2/MSH6 in one case...

  10. GATC sequence and mismatch repair in Escherichia coli.

    OpenAIRE

    Laengle-Rouault, F; Maenhaut-Michel, G; Radman, M

    1986-01-01

    The Escherichia coli mismatch repair system greatly improves DNA replication fidelity by repairing single mispaired and unpaired bases in newly synthesized DNA strands. Transient undermethylation of the GATC sequences makes the newly synthesized strands susceptible to mismatch repair enzymes. The role of unmethylated GATC sequences in mismatch repair was tested in transfection experiments with heteroduplex DNA of phage phi 174 without any GATC sequence or with two GATC sequences, containing i...

  11. Heterogenous mismatch-repair status in colorectal cancer

    DEFF Research Database (Denmark)

    Joost, Patrick; Veurink, Nynke; Holck, Susanne

    2014-01-01

    BACKGROUND: Immunohistochemical staining for mismatch repair proteins is efficient and widely used to identify mismatch repair defective tumors. The tumors typically show uniform and widespread loss of MMR protein staining. We identified and characterized colorectal cancers with alternative......, heterogenous mismatch repair protein staining in order to delineate expression patterns and underlying mechanisms. METHODS: Heterogenous staining patterns that affected at least one of the mismatch repair proteins MLH1, PMS2, MSH2 and MSH6 were identified in 14 colorectal cancers. Based on alternative....... CONCLUSIONS: Heterogenous mismatch repair status can be demonstrated in colorectal cancer. Though rare, attention to this phenomenon is recommended since it corresponds to differences in mismatch repair status that are relevant for correct classification. VIRTUAL SLIDES: The virtual slide(s) for this article...

  12. Disability and Skill Mismatch

    OpenAIRE

    Jones, Melanie K.; Sloane, Peter J.

    2009-01-01

    This paper integrates two strands of literature on overskilling and disability using the 2004 British Workplace Employment Relations Survey (WERS). It finds that the disabled are significantly more likely to be mismatched in the labour market, to suffer from a pay penalty and to have lower job satisfaction, the effects being stronger for the work-limited disabled. Giving workers more discretion over how they perform their work would significantly reduce these negative effects.

  13. Metrology of ground-based satellite validation: co-location mismatch and smoothing issues of total ozone comparisons

    Directory of Open Access Journals (Sweden)

    T. Verhoelst

    2015-12-01

    Full Text Available Comparisons with ground-based correlative measurements constitute a key component in the validation of satellite data on atmospheric composition. The error budget of these comparisons contains not only the measurement errors but also several terms related to differences in sampling and smoothing of the inhomogeneous and variable atmospheric field. A versatile system for Observing System Simulation Experiments (OSSEs, named OSSSMOSE, is used here to quantify these terms. Based on the application of pragmatic observation operators onto high-resolution atmospheric fields, it allows a simulation of each individual measurement, and consequently, also of the differences to be expected from spatial and temporal field variations between both measurements making up a comparison pair. As a topical case study, the system is used to evaluate the error budget of total ozone column (TOC comparisons between GOME-type direct fitting (GODFITv3 satellite retrievals from GOME/ERS2, SCIAMACHY/Envisat, and GOME-2/MetOp-A, and ground-based direct-sun and zenith–sky reference measurements such as those from Dobsons, Brewers, and zenith-scattered light (ZSL-DOAS instruments, respectively. In particular, the focus is placed on the GODFITv3 reprocessed GOME-2A data record vs. the ground-based instruments contributing to the Network for the Detection of Atmospheric Composition Change (NDACC. The simulations are found to reproduce the actual measurements almost to within the measurement uncertainties, confirming that the OSSE approach and its technical implementation are appropriate. This work reveals that many features of the comparison spread and median difference can be understood as due to metrological differences, even when using strict co-location criteria. In particular, sampling difference errors exceed measurement uncertainties regularly at most mid- and high-latitude stations, with values up to 10 % and more in extreme cases. Smoothing difference errors only

  14. Prognostic Impact of Deficient DNA Mismatch Repair in Patients With Stage III Colon Cancer From a Randomized Trial of FOLFOX-Based Adjuvant Chemotherapy

    Science.gov (United States)

    Sinicrope, Frank A.; Mahoney, Michelle R.; Smyrk, Thomas C.; Thibodeau, Stephen N.; Warren, Robert S.; Bertagnolli, Monica M.; Nelson, Garth D.; Goldberg, Richard M.; Sargent, Daniel J.; Alberts, Steven R.

    2013-01-01

    Purpose The association of deficient DNA mismatch repair (dMMR) with prognosis in patients with colon cancer treated with adjuvant fluorouracil, leucovorin, and oxaliplatin (FOLFOX) chemotherapy remains unknown. Patients and Methods Resected, stage III colon carcinomas from patients (N = 2,686) randomly assigned to FOLFOX ± cetuximab (North Central Cancer Treatment Group N0147 trial) were analyzed for mismatch repair (MMR) protein expression and mutations in BRAFV600E (exon 15) and KRAS (codons 12 and 13). Association of biomarkers with disease-free survival (DFS) was determined using Cox models. A validation cohort (Cancer and Leukemia Group B 88903 trial) was used. Results dMMR was detected in 314 (12%) of 2,580 tumors, of which 49.3% and 10.6% had BRAFV600E or KRAS mutations, respectively. MMR status was not prognostic overall (adjusted hazard ratio [HR], 0.82; 95% CI, 0.64 to 1.07; P = .14), yet significant interactions were found between MMR and primary tumor site (Pinteraction = .009) and lymph node category (N1 v N2; Pinteraction = .014). Favorable DFS was observed for dMMR versus proficient MMR proximal tumors (HR, 0.71; 95% CI, 0.53 to 0.94; P = .018) but not dMMR distal tumors (HR, 1.71; 95% CI, 0.99 to 2.95; P = .056), adjusting for mutations and covariates. Any survival benefit of dMMR was lost in N2 tumors. Mutations in BRAFV600E (HR, 1.37; 95% CI, 1.08 to 1.70; P = .009) or KRAS (HR, 1.44; 95% CI, 1.21 to 1.70; P < .001) were independently associated with worse DFS. The observed MMR by tumor site interaction was validated in an independent cohort of stage III colon cancers (Pinteraction = .037). Conclusion The prognostic impact of MMR depended on tumor site, and this interaction was validated in an independent cohort. Among dMMR cancers, proximal tumors had favorable outcome, whereas distal or N2 tumors had poor outcome. BRAF or KRAS mutations were independently associated with adverse outcome. PMID:24019539

  15. Mechanisms in E. coli and Human Mismatch Repair (Nobel Lecture).

    Science.gov (United States)

    Modrich, Paul

    2016-07-18

    DNA molecules are not completely stable, they are subject to chemical or photochemical damage and errors that occur during DNA replication resulting in mismatched base pairs. Through mechanistic studies Paul Modrich showed how replication errors are corrected by strand-directed mismatch repair in Escherichia coli and human cells. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Identification of a permissible HLA mismatch in hematopoietic stem cell transplantation

    Science.gov (United States)

    Fernandez-Viña, Marcelo A.; Wang, Tao; Lee, Stephanie J.; Haagenson, Michael; Aljurf, Mahmoud; Askar, Medhat; Battiwalla, Minoo; Baxter-Lowe, Lee-Ann; Gajewski, James; Jakubowski, Ann A.; Marino, Susana; Oudshoorn, Machteld; Marsh, Steven G. E.; Petersdorf, Effie W.; Schultz, Kirk; Turner, E. Victoria; Waller, Edmund K.; Woolfrey, Ann; Umejiego, John; Spellman, Stephen R.; Setterholm, Michelle

    2014-01-01

    In subjects mismatched in the HLA alleles C*03:03/C*03:04 no allogeneic cytotoxic T-lymphocyte responses are detected in vitro. Hematopoietic stem cell transplantation (HSCT) with unrelated donors (UDs) showed no association between the HLA-C allele mismatches (CAMMs) and adverse outcomes; antigen mismatches at this and mismatches other HLA loci are deleterious. The absence of effect of the CAMM may have resulted from the predominance of the mismatch C*03:03/C*03:04. Patients with hematologic malignancies receiving UD HSCT matched in 8/8 and 7/8 HLA alleles were examined. Transplants mismatched in HLA-C antigens or mismatched in HLA-A, -B, or -DRB1 presented significant differences (P HLA mismatches. PMID:24408320

  17. Addressing the Resource Requirements Mismatch

    National Research Council Canada - National Science Library

    Braun, William

    2003-01-01

    ... on the other, appear to be developing a requirements-resource mismatch. The goals and objectives of the transformation rhetoric intuitively resonate with the military's increasingly technologic culture...

  18. Skill Mismatch in Equilibrium Unemployment

    OpenAIRE

    Bachmann, Ronald

    2005-01-01

    We analyse the effect of skill mismatch in a search model of equilibrium unemployment with risk-neutral agents, endogenous job destruction, and two-sided ex-ante heterogeneity. First, we examine the interaction of labour market institu- tions and skill mismatch. We find that skill mismatch changes the results obtained in a model with ex ante homogeneity. Second, we analyse the interaction of skill mismatch and labour market institutions for the di®erence in the labour market experience of con...

  19. DOM Based XSS Detecting Method Based on Phantomjs

    Science.gov (United States)

    Dong, Ri-Zhan; Ling, Jie; Liu, Yi

    Because malicious code does not appear in html source code, DOM based XSS cannot be detected by traditional methods. By analyzing the causes of DOM based XSS, this paper proposes a detection method of DOM based XSS based on phantomjs. This paper uses function hijacking to detect dangerous operation and achieves a prototype system. Comparing with existing tools shows that the system improves the detection rate and the method is effective to detect DOM based XSS.

  20. Multi-lane detection based on multiple vanishing points detection

    Science.gov (United States)

    Li, Chuanxiang; Nie, Yiming; Dai, Bin; Wu, Tao

    2015-03-01

    Lane detection plays a significant role in Advanced Driver Assistance Systems (ADAS) for intelligent vehicles. In this paper we present a multi-lane detection method based on multiple vanishing points detection. A new multi-lane model assumes that a single lane, which has two approximately parallel boundaries, may not parallel to others on road plane. Non-parallel lanes associate with different vanishing points. A biological plausibility model is used to detect multiple vanishing points and fit lane model. Experimental results show that the proposed method can detect both parallel lanes and non-parallel lanes.

  1. Zepto-molar electrochemical detection of Brucella genome based on gold nanoribbons covered by gold nanoblooms

    Science.gov (United States)

    Rahi, Amid; Sattarahmady, Naghmeh; Heli, Hossein

    2015-12-01

    Gold nanoribbons covered by gold nanoblooms were sonoelectrodeposited on a polycrystalline gold surface at -1800 mV (vs. AgCl) with the assistance of ultrasound and co-occurrence of the hydrogen evolution reaction. The nanostructure, as a transducer, was utilized to immobilize a Brucella-specific probe and fabrication of a genosensor, and the process of immobilization and hybridization was detected by electrochemical methods, using methylene blue as a redox marker. The proposed method for detection of the complementary sequence, sequences with base-mismatched (one-, two- and three-base mismatches), and the sequence of non-complementary sequence was assayed. The fabricated genosensor was evaluated for the assay of the bacteria in the cultured and human samples without polymerase chain reactions (PCR). The genosensor could detect the complementary sequence with a calibration sensitivity of 0.40 μA dm3 mol-1, a linear concentration range of 10 zmol dm-3 to 10 pmol dm-3, and a detection limit of 1.71 zmol dm-3.

  2. The Mismatch between Students' Mental Models of Acids/Bases and Their Sources and Their Teacher's Anticipations Thereof

    Science.gov (United States)

    Lin, Jing-Wen; Chiu, Mei-Hung

    2010-01-01

    The aim of this study is to compare the characteristics and sources of students' mental models of acids and bases with a teacher's anticipations and, based on this comparison, to explore some possible explanations why motivated students might fail to learn from a subject-knowledgeable chemistry teacher. The study involves a chemistry teacher and…

  3. Mismatch sources in LDMOS devices

    NARCIS (Netherlands)

    Andricciola, Pietro; Andricciola, P.; Tuinhout, Hans

    2010-01-01

    This paper discusses the influence of different sources of DC parametric mismatch in an LDMOS. By comparing measurements and statistical simulations the impact on mismatch of the most important fluctuation causes is qualitatively evaluated. We demonstrate that, whereas the shape of the doping

  4. Prosthesis-patient mismatch

    Directory of Open Access Journals (Sweden)

    Philippe Pibarot

    2011-04-01

    Full Text Available Prosthesis-patient mismatch (PPM is present when the effective orifice area of the inserted prosthetic valve is too small in relation to body size. Its main hemodynamic consequence is to generate higher than expected gradients through normally functioning prosthetic valves. The purpose of this review is to present an update on the present state of knowledge with regards to diagnosis, prognosis and prevention of PPM. PPM is a frequent occurrence (20%–70% of aortic valve replacements that has been shown to be associated with worse hemodynamics, less regression of left ventricular hypertrophy, more cardiac events, and lower survival. Moreover, as opposed to most other risk factors, PPM can largely be prevented by using a prospective strategy at the time of operation.

  5. Design and analysis of mismatch probes for long oligonucleotide microarrays

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Ye; He, Zhili; Van Nostrand, Joy D.; Zhou, Jizhong

    2008-08-15

    Nonspecific hybridization is currently a major concern with microarray technology. One of most effective approaches to estimating nonspecific hybridizations in oligonucleotide microarrays is the utilization of mismatch probes; however, this approach has not been used for longer oligonucleotide probes. Here, an oligonucleotide microarray was constructed to evaluate and optimize parameters for 50-mer mismatch probe design. A perfect match (PM) and 28 mismatch (MM) probes were designed for each of ten target genes selected from three microorganisms. The microarrays were hybridized with synthesized complementary oligonucleotide targets at different temperatures (e.g., 42, 45 and 50 C). In general, the probes with evenly distributed mismatches were more distinguishable than those with randomly distributed mismatches. MM probes with 3, 4 and 5 mismatched nucleotides were differentiated for 50-mer oligonucleotide probes hybridized at 50, 45 and 42 C, respectively. Based on the experimental data generated from this study, a modified positional dependent nearest neighbor (MPDNN) model was constructed to adjust the thermodynamic parameters of matched and mismatched dimer nucleotides in the microarray environment. The MM probes with four flexible positional mismatches were designed using the newly established MPDNN model and the experimental results demonstrated that the redesigned MM probes could yield more consistent hybridizations. Conclusions: This study provides guidance on the design of MM probes for long oligonucleotides (e.g., 50 mers). The novel MPDNN model has improved the consistency for long MM probes, and this modeling method can potentially be used for the prediction of oligonucleotide microarray hybridizations.

  6. Potential fire detection based on Kalman-driven change detection

    CSIR Research Space (South Africa)

    Van Den Bergh, F

    2009-07-01

    Full Text Available A new active fire event detection algorithm for data collected with the Spinning Enhanced Visible and Infrared Imager (SEVIRI) sensor, based on the extended Kalman filter, is introduced. Instead of using the observed temperatures of the spatial...

  7. A new general model for predicting melting thermodynamics of complementary and mismatched B-form duplexes containing locked nucleic acids: application to probe design for digital PCR detection of somatic mutations.

    Science.gov (United States)

    Hughesman, Curtis; Fakhfakh, Kareem; Bidshahri, Roza; Lund, H Louise; Haynes, Charles

    2015-02-17

    Advances in real-time polymerase chain reaction (PCR), as well as the emergence of digital PCR (dPCR) and useful modified nucleotide chemistries, including locked nucleic acids (LNAs), have created the potential to improve and expand clinical applications of PCR through their ability to better quantify and differentiate amplification products, but fully realizing this potential will require robust methods for designing dual-labeled hydrolysis probes and predicting their hybridization thermodynamics as a function of their sequence, chemistry, and template complementarity. We present here a nearest-neighbor thermodynamic model that accurately predicts the melting thermodynamics of a short oligonucleotide duplexed either to its perfect complement or to a template containing mismatched base pairs. The model may be applied to pure-DNA duplexes or to duplexes for which one strand contains any number and pattern of LNA substitutions. Perturbations to duplex stability arising from mismatched DNA:DNA or LNA:DNA base pairs are treated at the Gibbs energy level to maintain statistical significance in the regressed model parameters. This approach, when combined with the model's accounting of the temperature dependencies of the melting enthalpy and entropy, permits accurate prediction of T(m) values for pure-DNA homoduplexes or LNA-substituted heteroduplexes containing one or two independent mismatched base pairs. Terms accounting for changes in solution conditions and terminal addition of fluorescent dyes and quenchers are then introduced so that the model may be used to accurately predict and thereby tailor the T(m) of a pure-DNA or LNA-substituted hydrolysis probe when duplexed either to its perfect-match template or to a template harboring a noncomplementary base. The model, which builds on classic nearest-neighbor thermodynamics, should therefore be of use to clinicians and biologists who require probes that distinguish and quantify two closely related alleles in either a

  8. Population-based screening versus case detection.

    Directory of Open Access Journals (Sweden)

    Thomas Ravi

    2002-01-01

    Full Text Available India has a large burden of blindness and population-based screening is a strategy commonly employed to detect disease and prevent morbidity. However, not all diseases are amenable to screening. This communication examines the issue of "population-based screening" versus "case detection" in the Indian scenario. Using the example of glaucoma, it demonstrates that given the poor infrastructure, for a "rare" disease, case detection is more effective than population-based screening.

  9. Mismatch repair gene expression in gastroesophageal cancers.

    Science.gov (United States)

    Dracea, Amelia; Angelescu, Cristina; Danciulescu, Mihaela; Ciurea, Marius; Ioana, Mihai; Burada, Florin

    2015-09-01

    Mismatch repair (MMR) genes play a critical role in maintaining genomic stability, and the impairment of MMR machinery is associated with different human cancers, mainly colorectal cancer. The purpose of our study was to analyze gene expression patterns of three MMR genes (MSH2, MHS6, and EXO1) in gastroesophageal cancers, a pathology in which the contribution of DNA repair genes remains essentially unclear. A total of 45 Romanian patients diagnosed with sporadic gastroesophageal cancers were included in this study. For each patient, MMR mRNA levels were measured in biopsied tumoral (T) and peritumoral (PT) tissues obtained by upper endoscopy. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) with specific TaqMan probes was used to measure gene expression levels for MSH2, MSH6, and EXO1 genes. A significant association was observed for the investigated MMR genes, all of which were detected to be upregulated in gastroesophageal tumor samples when compared with paired normal samples. In the stratified analysis, the association was limited to gastric adenocarcinoma samples. We found no statistically significant associations between MMR gene expression and tumor site or histological grade. In our study, MSH2, MSH6, and EXO1 genes were overexpressed in gastroesophageal cancers. Further investigations based on more samples are necessary to validate our findings.

  10. Radar-based hail detection

    Czech Academy of Sciences Publication Activity Database

    Skripniková, Kateřina; Řezáčová, Daniela

    2014-01-01

    Roč. 144, č. 1 (2014), s. 175-185 ISSN 0169-8095 R&D Projects: GA ČR(CZ) GAP209/11/2045; GA MŠk LD11044 Institutional support: RVO:68378289 Keywords : hail detection * weather radar * hail damage risk Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 2.844, year: 2014 http://www.sciencedirect.com/science/article/pii/S0169809513001804

  11. Audiovisual laughter detection based on temporal features

    NARCIS (Netherlands)

    Petridis, Stavros; Nijholt, Antinus; Nijholt, A.; Pantic, M.; Pantic, Maja; Poel, Mannes; Poel, M.; Hondorp, G.H.W.

    2008-01-01

    Previous research on automatic laughter detection has mainly been focused on audio-based detection. In this study we present an audiovisual approach to distinguishing laughter from speech based on temporal features and we show that the integration of audio and visual information leads to improved

  12. Modulation of the Singlet Oxygen Generation from the Double Strand DNA-SYBR Green I Complex Mediated by T-Melamine-T Mismatch for Visual Detection of Melamine.

    Science.gov (United States)

    Hu, Hao; Zhang, Jinyi; Ding, Yu; Zhang, Xinfeng; Xu, Kailai; Hou, Xiandeng; Wu, Peng

    2017-05-02

    Singlet oxygen ( 1 O 2 ), generated via photosensitization, has been proved to oxidize chromogenic substrates with neither H 2 O 2 oxidation nor enzyme (horseradish peroxidase, HRP) catalysis. Of the various methods for modulation of the 1 O 2 generation, DNA-controlled photosensitization received great attention. Therefore, integration of the formation/deformation DNA structures with DNA-controlled photosensitization will be extremely appealing in visual biosensor developments. Here, the stable melamine-thymine complex was explored in combination with DNA-controlled photosensitization for visual detection of melamine. A T-rich single stand DNA was utilized as the recognition unit. Upon the formation of the T-M-T complex, double stand DNA was formed, which was ready for the binding of SYBR Green I and activated the photosensitization. Subsequent oxidation of TMB allowed visual detection of melamine in dairy products, with spike-recoveries ranging from 94% to 106%.

  13. A Calibration Method for Nonlinear Mismatches in M-Channel Time-Interleaved Analog-to-Digital Converters Based on Hadamard Sequences

    Directory of Open Access Journals (Sweden)

    Husheng Liu

    2016-11-01

    Full Text Available The time-interleaved analog-to-digital converter (TIADC is an architecture used to achieve a high sampling rate and high dynamic performance. However, estimation and compensation methods are required to maintain the dynamic performance of the constituent analog-to-digital converters (ADCs due to channel mismatches. This paper proposes a blind adaptive method to calibrate the nonlinear mismatches in M-channel TIADCs (M-TIADCs. The nonlinearity-induced error signal is reconstructed by the proposed multiplier Hadamard transform (MHT structure, and the nonlinear parameters are estimated by the filtered-X least-mean square (FxLMS algorithm. The performance of cascade calibration is also analyzed. The numerical simulation results show that the proposed method consumes much less hardware resources while maintaining the calibration performance.

  14. Community-Based Intrusion Detection

    OpenAIRE

    Weigert, Stefan

    2017-01-01

    Today, virtually every company world-wide is connected to the Internet. This wide-spread connectivity has given rise to sophisticated, targeted, Internet-based attacks. For example, between 2012 and 2013 security researchers counted an average of about 74 targeted attacks per day. These attacks are motivated by economical, financial, or political interests and commonly referred to as “Advanced Persistent Threat (APT)” attacks. Unfortunately, many of these attacks are successful and the advers...

  15. Daytime Water Detection Based on Sky Reflections

    Science.gov (United States)

    Rankin, Arturo; Matthies, Larry; Bellutta, Paolo

    2011-01-01

    A water body s surface can be modeled as a horizontal mirror. Water detection based on sky reflections and color variation are complementary. A reflection coefficient model suggests sky reflections dominate the color of water at ranges > 12 meters. Water detection based on sky reflections: (1) geometrically locates the pixel in the sky that is reflecting on a candidate water pixel on the ground (2) predicts if the ground pixel is water based on color similarity and local terrain features. Water detection has been integrated on XUVs.

  16. DNA Mismatch Repair in Eukaryotes and Bacteria

    Directory of Open Access Journals (Sweden)

    Kenji Fukui

    2010-01-01

    Full Text Available DNA mismatch repair (MMR corrects mismatched base pairs mainly caused by DNA replication errors. The fundamental mechanisms and proteins involved in the early reactions of MMR are highly conserved in almost all organisms ranging from bacteria to human. The significance of this repair system is also indicated by the fact that defects in MMR cause human hereditary nonpolyposis colon cancers as well as sporadic tumors. To date, 2 types of MMRs are known: the human type and Escherichia coli type. The basic features of the former system are expected to be universal among the vast majority of organisms including most bacteria. Here, I review the molecular mechanisms of eukaryotic and bacterial MMR, emphasizing on the similarities between them.

  17. Footprint mismatch in lumbar total disc arthroplasty.

    Science.gov (United States)

    Gstoettner, Michaela; Michaela, Gstoettner; Heider, Denise; Denise, Heider; Liebensteiner, Michael; Bach, Christian Michael; Michael, Bach Christian

    2008-11-01

    Lumbar disc arthroplasty has become a popular modality for the treatment of degenerative disc disease. The dimensions of the implants are based on early published geometrical measurements of vertebrae; the majority of these were cadaver studies. The fit of the prosthesis in the intervertebral space is of utmost importance. An undersized implant may lead to subsidence, loosening and biomechanical failure due to an incorrect center of rotation. The aim of the present study was to measure the dimensions of lumbar vertebrae based on CT scans and assess the accuracy of match in currently available lumbar disc prostheses. A total of 240 endplates of 120 vertebrae were included in the study. The sagittal and mediolateral diameter of the upper and lower endplates were measured using a digital measuring system. For the levels L4/L5 and L5/S1, an inappropriate size match was noted in 98.8% (Prodisc L) and 97.6% (Charite) with regard to the anteroposterior diameter. Mismatch in the anterior mediolateral diameter was noted in 79.3% (Prodisc L) and 51.2% (Charite) while mismatch in the posterior mediolateral diameter was observed in 91.5% (Prodisc L) and 78% (Charite) of the endplates. Surgeons and manufacturers should be aware of the size mismatch of currently available lumbar disc prostheses, which may endanger the safety and efficacy of the procedure. Larger footprints of currently available total disc arthroplasties are required.

  18. Spike detection II: automatic, perception-based detection and clustering.

    Science.gov (United States)

    Wilson, S B; Turner, C A; Emerson, R G; Scheuer, M L

    1999-03-01

    We developed perception-based spike detection and clustering algorithms. The detection algorithm employs a novel, multiple monotonic neural network (MMNN). It is tested on two short-duration EEG databases containing 2400 spikes from 50 epilepsy patients and 10 control subjects. Previous studies are compared for database difficulty and reliability and algorithm accuracy. Automatic grouping of spikes via hierarchical clustering (using topology and morphology) is visually compared with hand marked grouping on a single record. The MMNN algorithm is found to operate close to the ability of a human expert while alleviating problems related to overtraining. The hierarchical and hand marked spike groupings are found to be strikingly similar. An automatic detection algorithm need not be as accurate as a human expert to be clinically useful. A user interface that allows the neurologist to quickly delete artifacts and determine whether there are multiple spike generators is sufficient.

  19. The Effect of Basepair Mismatch on DNA Strand Displacement.

    Science.gov (United States)

    Broadwater, D W Bo; Kim, Harold D

    2016-04-12

    DNA strand displacement is a key reaction in DNA homologous recombination and DNA mismatch repair and is also heavily utilized in DNA-based computation and locomotion. Despite its ubiquity in science and engineering, sequence-dependent effects of displacement kinetics have not been extensively characterized. Here, we measured toehold-mediated strand displacement kinetics using single-molecule fluorescence in the presence of a single basepair mismatch. The apparent displacement rate varied significantly when the mismatch was introduced in the invading DNA strand. The rate generally decreased as the mismatch in the invader was encountered earlier in displacement. Our data indicate that a single base pair mismatch in the invader stalls branch migration and displacement occurs via direct dissociation of the destabilized incumbent strand from the substrate strand. We combined both branch migration and direct dissociation into a model, which we term the concurrent displacement model, and used the first passage time approach to quantitatively explain the salient features of the observed relationship. We also introduce the concept of splitting probabilities to justify that the concurrent model can be simplified into a three-step sequential model in the presence of an invader mismatch. We expect our model to become a powerful tool to design DNA-based reaction schemes with broad functionality. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  20. Power Consumption Based Android Malware Detection

    Directory of Open Access Journals (Sweden)

    Hongyu Yang

    2016-01-01

    Full Text Available In order to solve the problem that Android platform’s sand-box mechanism prevents security protection software from accessing effective information to detect malware, this paper proposes a malicious software detection method based on power consumption. Firstly, the mobile battery consumption status information was obtained, and the Gaussian mixture model (GMM was built by using Mel frequency cepstral coefficients (MFCC. Then, the GMM was used to analyze power consumption; malicious software can be classified and detected through classification processing. Experiment results demonstrate that the function of an application and its power consumption have a close relationship, and our method can detect some typical malicious application software accurately.

  1. Apriori-based network intrusion detection system

    International Nuclear Information System (INIS)

    Wang Wenjin; Liu Junrong; Liu Baoxu

    2012-01-01

    With the development of network communication technology, more and more social activities run by Internet. In the meantime, the network information security is getting increasingly serious. Intrusion Detection System (IDS) has greatly improved the general security level of whole network. But there are still many problem exists in current IDS, e.g. high leak rate detection/false alarm rates and feature library need frequently upgrade. This paper presents an association-rule based IDS. This system can detect unknown attack by generate rules from training data. Experiment in last chapter proved the system has great accuracy on unknown attack detection. (authors)

  2. Vision Based Obstacle Detection in Uav Imaging

    Science.gov (United States)

    Badrloo, S.; Varshosaz, M.

    2017-08-01

    Detecting and preventing incidence with obstacles is crucial in UAV navigation and control. Most of the common obstacle detection techniques are currently sensor-based. Small UAVs are not able to carry obstacle detection sensors such as radar; therefore, vision-based methods are considered, which can be divided into stereo-based and mono-based techniques. Mono-based methods are classified into two groups: Foreground-background separation, and brain-inspired methods. Brain-inspired methods are highly efficient in obstacle detection; hence, this research aims to detect obstacles using brain-inspired techniques, which try to enlarge the obstacle by approaching it. A recent research in this field, has concentrated on matching the SIFT points along with, SIFT size-ratio factor and area-ratio of convex hulls in two consecutive frames to detect obstacles. This method is not able to distinguish between near and far obstacles or the obstacles in complex environment, and is sensitive to wrong matched points. In order to solve the above mentioned problems, this research calculates the dist-ratio of matched points. Then, each and every point is investigated for Distinguishing between far and close obstacles. The results demonstrated the high efficiency of the proposed method in complex environments.

  3. Ovarian cancer at young age: the contribution of mismatch-repair defects in a population-based series of epithelial ovarian

    DEFF Research Database (Denmark)

    Domanska, K; Malander, S; Måsbäck, A

    2007-01-01

    and endometrioid cancers were overrepresented and were diagnosed in 27% and 16% of the tumors, respectively. Immunostaining using antibodies against MLH1, PMS2, MSH2, and MSH6 was used to assess the mismatch-repair status and revealed loss of expression of MLH1/PMS2 in two cases, loss of MSH2/MSH6 in one case......At least one of ten patients with ovarian cancer is estimated to develop their tumor because of heredity with the breast and ovarian cancer syndrome due to mutations in the BRCA1 and BRCA2 genes and hereditary nonpolyposis colorectal cancer (HNPCC) being the major genetic causes. Cancer at young...

  4. Recent advances in biosensor based endotoxin detection.

    Science.gov (United States)

    Das, A P; Kumar, P S; Swain, S

    2014-01-15

    Endotoxins also referred to as pyrogens are chemically lipopolysaccharides habitually found in food, environment and clinical products of bacterial origin and are unavoidable ubiquitous microbiological contaminants. Pernicious issues of its contamination result in high mortality and severe morbidities. Standard traditional techniques are slow and cumbersome, highlighting the pressing need for evoking agile endotoxin detection system. The early and prompt detection of endotoxin assumes prime importance in health care, pharmacological and biomedical sectors. The unparalleled recognition abilities of LAL biosensors perched with remarkable sensitivity, high stability and reproducibility have bestowed it with persistent reliability and their possible fabrication for commercial applicability. This review paper entails an overview of various trends in current techniques available and other possible alternatives in biosensor based endotoxin detection together with its classification, epidemiological aspects, thrust areas demanding endotoxin control, commercially available detection sensors and a revolutionary unprecedented approach narrating the influence of omics for endotoxin detection. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. An SNMP based failure detection service

    OpenAIRE

    Wiesmann, Matthias; Urban, Peter; Defago, Xavier

    2006-01-01

    In this paper, we present the SNMP-FD system. This system is a novel failure detection service entirely based on the SNMP standard. The advantage of this approach is better interoperability, and the possibility to rely on different sources of information for failure detection, including network equipment. This, in turn, gives us more precise failure information. This paper presents the architecture of the SNMP-FD system and discusses its advantages, both from the system engineering and intero...

  6. Plagiarism Detection Based on SCAM Algorithm

    DEFF Research Database (Denmark)

    Anzelmi, Daniele; Carlone, Domenico; Rizzello, Fabio

    2011-01-01

    Plagiarism is a complex problem and considered one of the biggest in publishing of scientific, engineering and other types of documents. Plagiarism has also increased with the widespread use of the Internet as large amount of digital data is available. Plagiarism is not just direct copy but also...... paraphrasing, rewording, adapting parts, missing references or wrong citations. This makes the problem more difficult to handle adequately. Plagiarism detection techniques are applied by making a distinction between natural and programming languages. Our proposed detection process is based on natural language...... document. Our plagiarism detection system, like many Information Retrieval systems, is evaluated with metrics of precision and recall....

  7. Quantum Endpoint Detection Based on QRDA

    Science.gov (United States)

    Wang, Jian; Wang, Han; Song, Yan

    2017-10-01

    Speech recognition technology is widely used in many applications for man - machine interaction. To face more and more speech data, the computation of speech processing needs new approaches. The quantum computation is one of emerging computation technology and has been seen as useful computation model. So we focus on the basic operation of speech recognition processing, the voice activity detection, to present quantum endpoint detection algorithm. In order to achieve this algorithm, the n-bits quantum comparator circuit is given firstly. Then based on QRDA(Quantum Representation of Digital Audio), a quantum endpoint detection algorithm is presented. These quantum circuits could efficient process the audio data in quantum computer.

  8. Base pair mismatches and carcinogen-modified bases in DNA: an NMR study of G x T and G x O4meT pairing in dodecanucleotide duplexes

    International Nuclear Information System (INIS)

    Kalnik, M.W.; Kouchakdjian, M.; Li, B.F.L.; Swann, P.F.; Patel, D.J.

    1988-01-01

    High-resolution two-dimensional NMR studies have been completed on the self-complementary d(C-G-C-G-A-G-C-T-T-G-C-G) duplex (designated G x T 12-mer) and the self-complementary d(C-G-C-G-A-G-C-T-O 4 meT-G-C-G) duplex (designated G x O 4 meT 12-mer) containing G x T and G x O 4 meT pairs at identical positions four base pairs in from either end of the duplex. The exchangeable and nonexchangeable proton resonances have been assigned from an analysis of two-dimensional nuclear Overhauser enhancement (NOESY) spectra for the G x T 12-mer and G x O 4 meT 12-mer duplexes in H 2 O and D 2 O solution. The guanosine and thymidine imino protons in the G x T mismatch resonate at 10.57 and 11.98 ppm, respectively, and exhibit a strong NOE between themselves and to imino protons of flanking base pairs in the G x T 12-mer duplex. The large upfield chemical shift of this proton relative to that of the imino proton resonance of G in the G x T mismatch or in G x C base pairs indicates that hydrogen bonding to O 4 meT is either very weak or absent. This guanosine imino proton has an NOE to the OCH 3 group of O 4 meT across the pair and NOEs to the imino protons of flanking base pairs. Taken together with data from the NMR of nonexchangeable protons, this shows that both G and O 4 meT have anti-glycosidic torsion angles and are stacked into the duplex. Comparison of the intensity of the NOEs between the guanosine imino proton and the OCH 3 of O 4 meT as well as other protons in its vicinity demonstrates that the OCH 3 group of O 4 meT adopts the syn orientation with respect to N3 of the methylated thymidine. The authors propose an alternate base pairing mode stabilized by one short hydrogen bond between the 2-amino group of guanosine and the 2-carbonyl group of O 4 met

  9. On event-based optical flow detection

    Directory of Open Access Journals (Sweden)

    Tobias eBrosch

    2015-04-01

    Full Text Available Event-based sensing, i.e. the asynchronous detection of luminance changes, promises low-energy, high dynamic range, and sparse sensing. This stands in contrast to whole image frame-wise acquisition by standard cameras. Here, we systematically investigate the implications of event-based sensing in the context of visual motion, or flow, estimation. Starting from a common theoretical foundation, we discuss different principal approaches for optical flow detection ranging from gradient-based methods over plane-fitting to filter based methods and identify strengths and weaknesses of each class. Gradient-based methods for local motion integration are shown to suffer from the sparse encoding in address-event representations (AER. Approaches exploiting the local plane like structure of the event cloud, on the other hand, are shown to be well suited. Within this class, filter based approaches are shown to define a proper detection scheme which can also deal with the problem of representing multiple motions at a single location (motion transparency. A novel biologically inspired efficient motion detector is proposed, analyzed and experimentally validated. Furthermore, a stage of surround normalization is incorporated. Together with the filtering this defines a canonical circuit for motion feature detection. The theoretical analysis shows that such an integrated circuit reduces motion ambiguity in addition to decorrelating the representation of motion related activations.

  10. PARP-1 enhances the mismatch-dependence of 5′-directed excision in human mismatch repair in vitro

    Science.gov (United States)

    Liu, Yiyong; Kadyrov, Farid A.; Modrich, Paul

    2011-01-01

    End-directed mismatch-provoked excision has been reconstituted in several purified systems. While 3′-directed excision displays a mismatch dependence similar to that observed in nuclear extracts (≈ 20-fold), the mismatch dependence of 5′-directed excision is only 3 to 4-fold, significantly less than that in extracts (8 to 10-fold). Utilizing a fractionation-based approach, we have isolated a single polypeptide that enhances mismatch dependence of reconstituted 5′-directed excision and have shown it to be identical to poly[ADP-ribose] polymerase 1 (PARP-1). Titration of reconstituted excision reactions or PARP-1-depleted HeLa nuclear extract with purified PARP-1 showed that the protein specifically enhances mismatch dependence of 5′-directed excision. Analysis of a set of PARP-1 mutants revealed that the DNA binding domain and BRCT fold contribute to the regulation of excision specificity. Involvement of the catalytic domain is restricted to its ability to poly(ADP-ribosyl)ate PARP-1 in the presence of NAD+, likely through interference with DNA binding. Analysis of protein-protein interactions demonstrated that PARP-1 interacts with mismatch repair proteins MutSα, exonuclease 1, replication protein A (RPA), and as previously shown by others, replication factor C (RFC) and proliferating cell nuclear antigen (PCNA) as well. The BRCT fold plays an important role in the interaction of PARP-1 with the former three proteins. PMID:21945626

  11. Improved biosensor-based detection system

    DEFF Research Database (Denmark)

    2015-01-01

    Described is a new biosensor-based detection system for effector compounds, useful for in vivo applications in e.g. screening and selecting of cells which produce a small molecule effector compound or which take up a small molecule effector compound from its environment. The detection system...... comprises a protein or RNA-based biosensor for the effector compound which indirectly regulates the expression of a reporter gene via two hybrid proteins, providing for fewer false signals or less 'noise', tuning of sensitivity or other advantages over conventional systems where the biosensor directly...

  12. Image denoising based on noise detection

    Science.gov (United States)

    Jiang, Yuanxiang; Yuan, Rui; Sun, Yuqiu; Tian, Jinwen

    2018-03-01

    Because of the noise points in the images, any operation of denoising would change the original information of non-noise pixel. A noise detection algorithm based on fractional calculus was proposed to denoise in this paper. Convolution of the image was made to gain direction gradient masks firstly. Then, the mean gray was calculated to obtain the gradient detection maps. Logical product was made to acquire noise position image next. Comparisons in the visual effect and evaluation parameters after processing, the results of experiment showed that the denoising algorithms based on noise were better than that of traditional methods in both subjective and objective aspects.

  13. DNA-functionalized gold nanoparticle-based fluorescence polarization for the sensitive detection of silver ions.

    Science.gov (United States)

    Wang, Gongke; Wang, Shuangli; Yan, Changling; Bai, Guangyue; Liu, Yufang

    2018-04-05

    Despite their practical applications, Ag + ions are environmental pollutants and affect human health. So the effective detection methods of Ag + ions are imperative. Herein, we developed a simple, sensitive, selective, and cost-effective fluorescence polarization sensor for Ag + detection in aqueous solution using thiol-DNA-functionalized gold nanoparticles (AuNPs). In this sensing strategy, Ag + ions can specifically interact with a cytosine-cytosine (CC) mismatch in DNA duplexes and form stable metal-mediated cytosine-Ag + -cytosine (C-Ag + -C) base pairs. The formation of the C-Ag + -C complex results in evident changes in the molecular volume and fluorescence polarization signal. To achieve our aims, we prepared two complementary DNA strands containing C-base mismatches (probe A: 5'-SH-A 10 -TACCACTCCTCAC-3' and probe B: 5'-TCCTCACCAGTCCTA-FAM-3'). The stable hybridization between probe A and probe B occurs with the formation of the C-Ag + -C complex in the presence of Ag + ions, leading to obvious fluorescence quenching in comparison to the system without AuNP enhancement. The assay can be used to identify nanomolar levels of Ag + within 6 min at room temperature, and has extremely high specificity for Ag + , even in the presence of higher concentrations of interfering metal ions. Furthermore, the sensor was successfully applied to the detection of Ag + ions in environmental water samples and showed excellent selectivity and high sensitivity, implying its promising application in the future. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Educational Mismatch and Self-Employment

    Science.gov (United States)

    Bender, Keith A.; Roche, Kristen

    2013-01-01

    Previous research on educational mismatch concentrates on estimating its labor market consequences but with a focus on wage and salary workers. This paper examines the far less studied influence of mismatch on the self-employed. Using a sample of workers in science and engineering fields, results show larger earnings penalties for mismatch among…

  15. Visual-Functional Mismatch Between Coronary Angiography, Fractional Flow Reserve, and Quantitative Coronary Angiography.

    Science.gov (United States)

    Safi, Morteza; Eslami, Vahid; Namazi, Mohammad Hasan; Vakili, Hossain; Saadat, Habib; Alipourparsa, Saeid; Adibi, Ali; Movahed, Mohammad Reza

    2016-12-01

    Anatomical and functional mismatches are not uncommon in the assessment of coronary lesions. The aim of this study was to identify clinical and lesion-specific factors affecting angiographic, anatomical, and functional mismatch in intermediate coronary lesions. In patients who underwent coronary angiography for clinical reasons, fractional flow reserve (FFR), and quantitative coronary angiography (QCA) analyses for intermediate stenotic lesions were performed simultaneously. Mismatches between the measured values were analyzed. A total of 95 intermediate lesions were assessed simultaneously by visual angiography, FFR, and QCA. The visual-FFR mismatch was found in 40% of the lesions while reverse visual-FFR mismatch was determined in nearly 14% of the lesions. Mismatch and reverse mismatch between FFR and QCA parameters were observed in 10 and 23% of the lesions. FFR value was significant in 32% of the lesions while visually significant stenosis was shown in 61% of the lesions. Among the visual-FFR reverse mismatch group, the prevalence of culprit lesions within the left anterior descending (LAD) was significantly higher than other vessels ( p value mismatches in analyses of intermediate coronary lesions. LAD lesions showed the highest mismatch. Angiographic or QCA estimation of lesion severity has consistently resulted in inappropriate stenting of functionally nonsignificant lesions or undertreatment of significant lesions based on FFR.

  16. Native mass spectrometry provides direct evidence for DNA mismatch-induced regulation of asymmetric nucleotide binding in mismatch repair protein MutS

    NARCIS (Netherlands)

    M.C. Monti; S.X. Cohen (Serge); A. Fish (Alexander); H.H.K. Winterwerp (Herrie); A. Barendregt (Arjan); P. Friedhoff (Peter); A. Perrakis (Anastassis); A.J.R. Heck (Albert); T.K. Sixma (Titia); R.H.H. van den Heuvel (Robert); J.H.G. Lebbink (Joyce)

    2011-01-01

    textabstractThe DNA mismatch repair protein MutS recognizes mispaired bases in DNA and initiates repair in an ATP-dependent manner. Understanding of the allosteric coupling between DNA mismatch recognition and two asymmetric nucleotide binding sites at opposing sides of the MutS dimer requires

  17. Seizure detection algorithms based on EMG signals

    DEFF Research Database (Denmark)

    Conradsen, Isa

    Background: the currently used non-invasive seizure detection methods are not reliable. Muscle fibers are directly connected to the nerves, whereby electric signals are generated during activity. Therefore, an alarm system on electromyography (EMG) signals is a theoretical possibility. Objective......: to show whether medical signal processing of EMG data is feasible for detection of epileptic seizures. Methods: EMG signals during generalised seizures were recorded from 3 patients (with 20 seizures in total). Two possible medical signal processing algorithms were tested. The first algorithm was based...... the frequency-based algorithm was efficient for detecting the seizures in the third patient. Conclusion: Our results suggest that EMG signals could be used to develop an automatic seizuredetection system. However, different patients might require different types of algorithms /approaches....

  18. Tornado Detection Based on Seismic Signal.

    Science.gov (United States)

    Tatom, Frank B.; Knupp, Kevin R.; Vitton, Stanley J.

    1995-02-01

    At the present time the only generally accepted method for detecting when a tornado is on the ground is human observation. Based on theoretical considerations combined with eyewitness testimony, there is strong reason to believe that a tornado in contact with the ground transfers a significant amount of energy into the ground. The amount of energy transferred depends upon the intensity of the tornado and the characteristics of the surface. Some portion of this energy takes the form of seismic waves, both body and surface waves. Surface waves (Rayleigh and possibly Love) represent the most likely type of seismic signal to be detected. Based on the existence of such a signal, a seismic tornado detector appears conceptually possible. The major concerns for designing such a detector are range of detection and discrimination between the tornadic signal and other types of surface waves generated by ground transportation equipment, high winds, or other nontornadic sources.

  19. Mismatch-mediated error prone repair at the immunoglobulin genes.

    Science.gov (United States)

    Chahwan, Richard; Edelmann, Winfried; Scharff, Matthew D; Roa, Sergio

    2011-12-01

    The generation of effective antibodies depends upon somatic hypermutation (SHM) and class-switch recombination (CSR) of antibody genes by activation induced cytidine deaminase (AID) and the subsequent recruitment of error prone base excision and mismatch repair. While AID initiates and is required for SHM, more than half of the base changes that accumulate in V regions are not due to the direct deamination of dC to dU by AID, but rather arise through the recruitment of the mismatch repair complex (MMR) to the U:G mismatch created by AID and the subsequent perversion of mismatch repair from a high fidelity process to one that is very error prone. In addition, the generation of double-strand breaks (DSBs) is essential during CSR, and the resolution of AID-generated mismatches by MMR to promote such DSBs is critical for the efficiency of the process. While a great deal has been learned about how AID and MMR cause hypermutations and DSBs, it is still unclear how the error prone aspect of these processes is largely restricted to antibody genes. The use of knockout models and mice expressing mismatch repair proteins with separation-of-function point mutations have been decisive in gaining a better understanding of the roles of each of the major MMR proteins and providing further insight into how mutation and repair are coordinated. Here, we review the cascade of MMR factors and repair signals that are diverted from their canonical error free role and hijacked by B cells to promote genetic diversification of the Ig locus. This error prone process involves AID as the inducer of enzymatically-mediated DNA mismatches, and a plethora of downstream MMR factors acting as sensors, adaptors and effectors of a complex and tightly regulated process from much of which is not yet well understood. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  20. Water Detection Based on Object Reflections

    Science.gov (United States)

    Rankin, Arturo L.; Matthies, Larry H.

    2012-01-01

    Water bodies are challenging terrain hazards for terrestrial unmanned ground vehicles (UGVs) for several reasons. Traversing through deep water bodies could cause costly damage to the electronics of UGVs. Additionally, a UGV that is either broken down due to water damage or becomes stuck in a water body during an autonomous operation will require rescue, potentially drawing critical resources away from the primary operation and increasing the operation cost. Thus, robust water detection is a critical perception requirement for UGV autonomous navigation. One of the properties useful for detecting still water bodies is that their surface acts as a horizontal mirror at high incidence angles. Still water bodies in wide-open areas can be detected by geometrically locating the exact pixels in the sky that are reflecting on candidate water pixels on the ground, predicting if ground pixels are water based on color similarity to the sky and local terrain features. But in cluttered areas where reflections of objects in the background dominate the appearance of the surface of still water bodies, detection based on sky reflections is of marginal value. Specifically, this software attempts to solve the problem of detecting still water bodies on cross-country terrain in cluttered areas at low cost.

  1. Community detection based on network communicability

    Science.gov (United States)

    Estrada, Ernesto

    2011-03-01

    We propose a new method for detecting communities based on the concept of communicability between nodes in a complex network. This method, designated as N-ComBa K-means, uses a normalized version of the adjacency matrix to build the communicability matrix and then applies K-means clustering to find the communities in a graph. We analyze how this method performs for some pathological cases found in the analysis of the detection limit of communities and propose some possible solutions on the basis of the analysis of the ratio of local to global densities in graphs. We use four different quality criteria for detecting the best clustering and compare the new approach with the Girvan-Newman algorithm for the analysis of two "classical" networks: karate club and bottlenose dolphins. Finally, we analyze the more challenging case of homogeneous networks with community structure, for which the Girvan-Newman completely fails in detecting any clustering. The N-ComBa K-means approach performs very well in these situations and we applied it to detect the community structure in an international trade network of miscellaneous manufactures of metal having these characteristics. Some final remarks about the general philosophy of community detection are also discussed.

  2. Wavelet-frame-based microcalcification detection

    Science.gov (United States)

    Chang, Charles C.; Wu, Hsien-Hsun S.; Liu, Jyh-Charn S.; Chui, Charles K.

    1997-10-01

    As the leading cause of death for adult women under 54 years of age in the United States, breast cancer accounts for 29% of all cancers in women. Early diagnosis of breast cancer is the most effective approach to reduce death rate. The rapid climbing of the health care cost further reiterates the importance of cost-effective, accurate screening tools for breast cancer. This paper proposes a wavelet frame based computer algorithm for screening of microcalcifications on digitized mammographical imagery. Despite its simplicity, the discrete wavelet transform (DWT) of compactly supported wavelets has been effectively used for detection of various types of signals. However, the shifting variant property of DWT makes it very unstable for detection of minute microcalcifications. Although increasing the sampling rate will improve the detection probability, this approach will drastically increase the size of mammographical images. The wavelet frame transform can be easily derived from the DWT algorithm by eliminating its down sampling step. The subtle difference between DWT and WF in down sampling is shown to be critical to the accuracy of microcalcifications detection. Without any down sampling, local image information at different scales is preserved. By joint thresholding of wavelet coefficients at different scales, one can accurately pin point suspected microcalcifications. A simple partitioning technique enables the detection algorithm to process image blocks independently. Four different partitioning techniques have been compared, and the method of repeating the end value on each partition boundary has the least significant impact on the detection accuracy.

  3. DIFFERENTIAL SEARCH ALGORITHM BASED EDGE DETECTION

    Directory of Open Access Journals (Sweden)

    M. A. Gunen

    2016-06-01

    Full Text Available In this paper, a new method has been presented for the extraction of edge information by using Differential Search Optimization Algorithm. The proposed method is based on using a new heuristic image thresholding method for edge detection. The success of the proposed method has been examined on fusion of two remote sensed images. The applicability of the proposed method on edge detection and image fusion problems have been analysed in detail and the empirical results exposed that the proposed method is useful for solving the mentioned problems.

  4. Reverse ventilation--perfusion mismatch

    Energy Technology Data Exchange (ETDEWEB)

    Palmaz, J.C.; Barnett, C.A.; Reich, S.B.; Krumpe, P.E.; Farrer, P.A.

    1984-01-01

    Patients having lobar airway obstruction or consolidation usually have decreases of both ventilation and perfusion on lung scans. We report three patients in whom hypoxic vasoconstriction was apparently incomplete, resulting in a ''reversed'' ventilation-perfusion mismatch. Perfusion of the hypoxic lobe on the radionuclide scan was associated with metabolic alkalosis, pulmonary venous and pulmonary arterial hypertension in these patients.

  5. Electrochemical DNA biosensor based on avidin-biotin conjugation for influenza virus (type A) detection

    Science.gov (United States)

    Chung, Da-Jung; Kim, Ki-Chul; Choi, Seong-Ho

    2011-09-01

    An electrochemical DNA biosensor (E-DNA biosensor) was fabricated by avidin-biotin conjugation of a biotinylated probe DNA, 5'-biotin-ATG AGT CTT CTA ACC GAG GTC GAA-3', and an avidin-modified glassy carbon electrode (GCE) to detect the influenza virus (type A). An avidin-modified GCE was prepared by the reaction of avidin and a carboxylic acid-modified GCE, which was synthesized by the electrochemical reduction of 4-carboxyphenyl diazonium salt. The current value of the E-DNA biosensor was evaluated after hybridization of the probe DNA and target DNA using cyclic voltammetry (CV). The current value decreased after the hybridization of the probe DNA and target DNA. The DNA that was used follows: complementary target DNA, 5'-TTC GAC CTC GGT TAG AAG ACT CAT-3' and two-base mismatched DNA, 5'-TTC GAC AGC GGT TAT AAG ACT CAT-3'.

  6. Memory-based detection of rare sound feature combinations in anesthetized rats.

    Science.gov (United States)

    Astikainen, Piia; Ruusuvirta, Timo; Wikgren, Jan; Penttonen, Markku

    2006-10-02

    It is unclear whether the ability of the brain to discriminate rare from frequently repeated combinations of sound features is limited to the normal sleep/wake cycle. We recorded epidural auditory event-related potentials in urethane-anesthetized rats presented with rare tones ('deviants') interspersed with frequently repeated ones ('standards'). Deviants differed from standards either in frequency alone or in frequency combined with intensity. In both cases, deviants elicited event-related potentials exceeding in amplitude event-related potentials to standards between 76 and 108 ms from the stimulus onset, suggesting the independence of the underlying integrative and memory-based change detection mechanisms of the brain from the normal sleep/wake cycle. The relations of these event-related potentials to mismatch negativity and N1 in humans are addressed.

  7. Mismatch repair balances leading and lagging strand DNA replication fidelity.

    Directory of Open Access Journals (Sweden)

    Scott A Lujan

    Full Text Available The two DNA strands of the nuclear genome are replicated asymmetrically using three DNA polymerases, α, δ, and ε. Current evidence suggests that DNA polymerase ε (Pol ε is the primary leading strand replicase, whereas Pols α and δ primarily perform lagging strand replication. The fact that these polymerases differ in fidelity and error specificity is interesting in light of the fact that the stability of the nuclear genome depends in part on the ability of mismatch repair (MMR to correct different mismatches generated in different contexts during replication. Here we provide the first comparison, to our knowledge, of the efficiency of MMR of leading and lagging strand replication errors. We first use the strand-biased ribonucleotide incorporation propensity of a Pol ε mutator variant to confirm that Pol ε is the primary leading strand replicase in Saccharomyces cerevisiae. We then use polymerase-specific error signatures to show that MMR efficiency in vivo strongly depends on the polymerase, the mismatch composition, and the location of the mismatch. An extreme case of variation by location is a T-T mismatch that is refractory to MMR. This mismatch is flanked by an AT-rich triplet repeat sequence that, when interrupted, restores MMR to > 95% efficiency. Thus this natural DNA sequence suppresses MMR, placing a nearby base pair at high risk of mutation due to leading strand replication infidelity. We find that, overall, MMR most efficiently corrects the most potentially deleterious errors (indels and then the most common substitution mismatches. In combination with earlier studies, the results suggest that significant differences exist in the generation and repair of Pol α, δ, and ε replication errors, but in a generally complementary manner that results in high-fidelity replication of both DNA strands of the yeast nuclear genome.

  8. Frequency Based Fault Detection in Wind Turbines

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2014-01-01

    In order to obtain lower cost of energy for wind turbines fault detection and accommodation is important. Expensive condition monitoring systems are often used to monitor the condition of rotating and vibrating system parts. One example is the gearbox in a wind turbine. This system is operated...... in parallel to the control system, using different computers and additional often expensive sensors. In this paper a simple filter based algorithm is proposed to detect changes in a resonance frequency in a system, exemplified with faults resulting in changes in the resonance frequency in the wind turbine...... turbine fault detection and fault tolerant control benchmark model, in which one of the included faults results in a change in the gear box resonance frequency. This evaluation shows the potential of the proposed scheme to monitor the condition of wind turbine gear boxes in the existing control system....

  9. Auditory mismatch impairments are characterized by core neural dysfunctions in schizophrenia.

    Science.gov (United States)

    Gaebler, Arnim Johannes; Mathiak, Klaus; Koten, Jan Willem; König, Andrea Anna; Koush, Yury; Weyer, David; Depner, Conny; Matentzoglu, Simeon; Edgar, James Christopher; Willmes, Klaus; Zvyagintsev, Mikhail

    2015-05-01

    Major theories on the neural basis of schizophrenic core symptoms highlight aberrant salience network activity (insula and anterior cingulate cortex), prefrontal hypoactivation, sensory processing deficits as well as an impaired connectivity between temporal and prefrontal cortices. The mismatch negativity is a potential biomarker of schizophrenia and its reduction might be a consequence of each of these mechanisms. In contrast to the previous electroencephalographic studies, functional magnetic resonance imaging may disentangle the involved brain networks at high spatial resolution and determine contributions from localized brain responses and functional connectivity to the schizophrenic impairments. Twenty-four patients and 24 matched control subjects underwent functional magnetic resonance imaging during an optimized auditory mismatch task. Haemodynamic responses and functional connectivity were compared between groups. These data sets further entered a diagnostic classification analysis to assess impairments on the individual patient level. In the control group, mismatch responses were detected in the auditory cortex, prefrontal cortex and the salience network (insula and anterior cingulate cortex). Furthermore, mismatch processing was associated with a deactivation of the visual system and the dorsal attention network indicating a shift of resources from the visual to the auditory domain. The patients exhibited reduced activation in all of the respective systems (right auditory cortex, prefrontal cortex, and the salience network) as well as reduced deactivation of the visual system and the dorsal attention network. Group differences were most prominent in the anterior cingulate cortex and adjacent prefrontal areas. The latter regions also exhibited a reduced functional connectivity with the auditory cortex in the patients. In the classification analysis, haemodynamic responses yielded a maximal accuracy of 83% based on four features; functional connectivity

  10. Water Detection Based on Color Variation

    Science.gov (United States)

    Rankin, Arturo L.

    2012-01-01

    This software has been designed to detect water bodies that are out in the open on cross-country terrain at close range (out to 30 meters), using imagery acquired from a stereo pair of color cameras mounted on a terrestrial, unmanned ground vehicle (UGV). This detector exploits the fact that the color variation across water bodies is generally larger and more uniform than that of other naturally occurring types of terrain, such as soil and vegetation. Non-traversable water bodies, such as large puddles, ponds, and lakes, are detected based on color variation, image intensity variance, image intensity gradient, size, and shape. At ranges beyond 20 meters, water bodies out in the open can be indirectly detected by detecting reflections of the sky below the horizon in color imagery. But at closer range, the color coming out of a water body dominates sky reflections, and the water cue from sky reflections is of marginal use. Since there may be times during UGV autonomous navigation when a water body does not come into a perception system s field of view until it is at close range, the ability to detect water bodies at close range is critical. Factors that influence the perceived color of a water body at close range are the amount and type of sediment in the water, the water s depth, and the angle of incidence to the water body. Developing a single model of the mixture ratio of light reflected off the water surface (to the camera) to light coming out of the water body (to the camera) for all water bodies would be fairly difficult. Instead, this software detects close water bodies based on local terrain features and the natural, uniform change in color that occurs across the surface from the leading edge to the trailing edge.

  11. Ionizing particle detection based on phononic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Aly, Arafa H., E-mail: arafa16@yahoo.com, E-mail: arafa.hussien@science.bsu.edu.eg; Mehaney, Ahmed; Eissa, Mostafa F. [Physics Department, Faculty of Science, Beni-Suef University, Beni-Suef (Egypt)

    2015-08-14

    Most conventional radiation detectors are based on electronic or photon collections. In this work, we introduce a new and novel type of ionizing particle detector based on phonon collection. Helium ion radiation treats tumors with better precision. There are nine known isotopes of helium, but only helium-3 and helium-4 are stable. Helium-4 is formed in fusion reactor technology and in enormous quantities during Big Bang nucleo-synthesis. In this study, we introduce a technique for helium-4 ion detection (sensing) based on the innovative properties of the new composite materials known as phononic crystals (PnCs). PnCs can provide an easy and cheap technique for ion detection compared with conventional methods. PnC structures commonly consist of a periodic array of two or more materials with different elastic properties. The two materials are polymethyl-methacrylate and polyethylene polymers. The calculations showed that the energies lost to target phonons are maximized at 1 keV helium-4 ion energy. There is a correlation between the total phonon energies and the transmittance of PnC structures. The maximum transmission for phonons due to the passage of helium-4 ions was found in the case of making polyethylene as a first layer in the PnC structure. Therefore, the concept of ion detection based on PnC structure is achievable.

  12. Skeleton-Based Abnormal Gait Detection

    Directory of Open Access Journals (Sweden)

    Trong-Nguyen Nguyen

    2016-10-01

    Full Text Available Human gait analysis plays an important role in musculoskeletal disorder diagnosis. Detecting anomalies in human walking, such as shuffling gait, stiff leg or unsteady gait, can be difficult if the prior knowledge of such a gait pattern is not available. We propose an approach for detecting abnormal human gait based on a normal gait model. Instead of employing the color image, silhouette, or spatio-temporal volume, our model is created based on human joint positions (skeleton in time series. We decompose each sequence of normal gait images into gait cycles. Each human instant posture is represented by a feature vector which describes relationships between pairs of bone joints located in the lower body. Such vectors are then converted into codewords using a clustering technique. The normal human gait model is created based on multiple sequences of codewords corresponding to different gait cycles. In the detection stage, a gait cycle with normality likelihood below a threshold, which is determined automatically in the training step, is assumed as an anomaly. The experimental results on both marker-based mocap data and Kinect skeleton show that our method is very promising in distinguishing normal and abnormal gaits with an overall accuracy of 90.12%.

  13. An FPGA-Based People Detection System

    Directory of Open Access Journals (Sweden)

    James J. Clark

    2005-05-01

    Full Text Available This paper presents an FPGA-based system for detecting people from video. The system is designed to use JPEG-compressed frames from a network camera. Unlike previous approaches that use techniques such as background subtraction and motion detection, we use a machine-learning-based approach to train an accurate detector. We address the hardware design challenges involved in implementing such a detector, along with JPEG decompression, on an FPGA. We also present an algorithm that efficiently combines JPEG decompression with the detection process. This algorithm carries out the inverse DCT step of JPEG decompression only partially. Therefore, it is computationally more efficient and simpler to implement, and it takes up less space on the chip than the full inverse DCT algorithm. The system is demonstrated on an automated video surveillance application and the performance of both hardware and software implementations is analyzed. The results show that the system can detect people accurately at a rate of about 2.5 frames per second on a Virtex-II 2V1000 using a MicroBlaze processor running at 75 MHz, communicating with dedicated hardware over FSL links.

  14. Tensor-based spatiotemporal saliency detection

    Science.gov (United States)

    Dou, Hao; Li, Bin; Deng, Qianqian; Zhang, LiRui; Pan, Zhihong; Tian, Jinwen

    2018-03-01

    This paper proposes an effective tensor-based spatiotemporal saliency computation model for saliency detection in videos. First, we construct the tensor representation of video frames. Then, the spatiotemporal saliency can be directly computed by the tensor distance between different tensors, which can preserve the complete temporal and spatial structure information of object in the spatiotemporal domain. Experimental results demonstrate that our method can achieve encouraging performance in comparison with the state-of-the-art methods.

  15. Frequency-based Vehicle Idling Detection

    OpenAIRE

    Kai-Chao Yang; Chih-Ting Kuo; Chun-Yu Chen; Chih-Chyau Yang; Chien-Ming Wu; Chun-Ming Huang

    2014-01-01

    Continuous increases in fuel prices and environmental awareness have raised the importance of reducing vehicle emissions, with many national governments passing anti-idling laws. To reduce air pollution and fuel consumption, we propose a frequency-based vehicle idling detection method to remind drivers to turn off the engine vehicle idling exceeds a certain time threshold. The method is implemented in existing handheld devices without any modification to the car or engine, making the solution...

  16. ABO-Mismatched Allogeneic Hematopoietic Stem Cell Transplantation.

    Science.gov (United States)

    Worel, Nina

    2016-01-01

    Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative option for a variety of malignant and non-malignant hematological and congenital diseases. Due to the fact that the human leukocyte antigen system is inherited independently of the blood group system, approximately 40-50% of all HSCTs are performed across the ABO blood group barrier. The expected immune-hematological consequences after transplantation of an ABO-mismatched stem cell graft are immediate and delayed hemolytic complications due to presence of isohemagglutinins or passenger lymphocyte syndrome. The risks of these complications can partially be prevented by graft manipulation and appropriate transfusion support. Dependent on the kind of ABO mismatch, different effects on engraftment have been observed, e.g. delayed red blood cell recovery and pure red cell aplasia. Data on incidence of acute graft-versus-host disease (GVHD), non-relapse mortality, relapse, and overall survival are inconsistent as most studies include limited patient numbers, various graft sources, and different conditioning and GVHD prophylaxis regimens. This makes it difficult to detect a consistent effect of ABO-mismatched transplantation in the literature. However, knowledge of expectable complications and close monitoring of patients helps to detect problems early and to treat patients efficiently, thus reducing the number of fatal or life-threatening events caused by ABO-mismatched HSCT.

  17. Fluorescence quenching based alkaline phosphatase activity detection.

    Science.gov (United States)

    Mei, Yaqi; Hu, Qiong; Zhou, Baojing; Zhang, Yonghui; He, Minhui; Xu, Ting; Li, Feng; Kong, Jinming

    2018-01-01

    Simple and fast detection of alkaline phosphatase (ALP) activity is of great importance for diagnostic and analytical applications. In this work, we report a turn-off approach for the real-time detection of ALP activity on the basis of the charge transfer induced fluorescence quenching of the Cu(BCDS) 2 2- (BCDS = bathocuproine disulfonate) probe. Initially, ALP can enzymatically hydrolyze the substrate ascorbic acid 2-phosphate to release ascorbic acid (AA). Subsequently, the AA-mediated reduction of the Cu(BCDS) 2 2- probe, which displays an intense photoluminescence band at the wavelength of 402nm, leads to the static quenching of fluorescence of the probe as a result of charge transfer. The underlying mechanism of the fluorescence quenching was demonstrated by quantum mechanical calculations. The Cu(BCDS) 2 2- probe features a large Stokes shift (86nm) and is highly immune to photo bleaching. In addition, this approach is free of elaborately designed fluorescent probes and allows the detection of ALP activity in a real-time manner. Under optimal conditions, it provides a fast and sensitive detection of ALP activity within the dynamic range of 0-220mUmL -1 , with a detection limit down to 0.27mUmL -1 . Results demonstrate that it is highly selective, and applicable to the screening of ALP inhibitors in drug discovery. More importantly, it shows a good analytical performance for the direct detection of the endogenous ALP levels of undiluted human serum and even whole blood samples. Therefore, the proposed charge transfer based approach has great potential in diagnostic and analytical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. QRS detection based ECG quality assessment

    International Nuclear Information System (INIS)

    Hayn, Dieter; Jammerbund, Bernhard; Schreier, Günter

    2012-01-01

    Although immediate feedback concerning ECG signal quality during recording is useful, up to now not much literature describing quality measures is available. We have implemented and evaluated four ECG quality measures. Empty lead criterion (A), spike detection criterion (B) and lead crossing point criterion (C) were calculated from basic signal properties. Measure D quantified the robustness of QRS detection when applied to the signal. An advanced Matlab-based algorithm combining all four measures and a simplified algorithm for Android platforms, excluding measure D, were developed. Both algorithms were evaluated by taking part in the Computing in Cardiology Challenge 2011. Each measure's accuracy and computing time was evaluated separately. During the challenge, the advanced algorithm correctly classified 93.3% of the ECGs in the training-set and 91.6 % in the test-set. Scores for the simplified algorithm were 0.834 in event 2 and 0.873 in event 3. Computing time for measure D was almost five times higher than for other measures. Required accuracy levels depend on the application and are related to computing time. While our simplified algorithm may be accurate for real-time feedback during ECG self-recordings, QRS detection based measures can further increase the performance if sufficient computing power is available. (paper)

  19. Reset Tree-Based Optical Fault Detection

    Directory of Open Access Journals (Sweden)

    Howon Kim

    2013-05-01

    Full Text Available In this paper, we present a new reset tree-based scheme to protect cryptographic hardware against optical fault injection attacks. As one of the most powerful invasive attacks on cryptographic hardware, optical fault attacks cause semiconductors to misbehave by injecting high-energy light into a decapped integrated circuit. The contaminated result from the affected chip is then used to reveal secret information, such as a key, from the cryptographic hardware. Since the advent of such attacks, various countermeasures have been proposed. Although most of these countermeasures are strong, there is still the possibility of attack. In this paper, we present a novel optical fault detection scheme that utilizes the buffers on a circuit’s reset signal tree as a fault detection sensor. To evaluate our proposal, we model radiation-induced currents into circuit components and perform a SPICE simulation. The proposed scheme is expected to be used as a supplemental security tool.

  20. Zero energy buildings and mismatch compensation factors

    DEFF Research Database (Denmark)

    Lund, Henrik; Marszal, Anna Joanna; Heiselberg, Per

    2011-01-01

    This paper takes an overall energy system approach to analysing the mismatch problem of zero energy and zero emission buildings (ZEBs). The mismatch arises from hourly differences in energy production and consumption at the building level and results in the need for exchange of electricity via...... the public grid even though the building has an annual net-exchange of zero. This paper argues that, when looked upon from the viewpoint of the overall electricity supply system, a mismatch can be both negative and positive. Moreover, there are often both an element of levelling out mismatches between...... individual buildings and an element of economy of scale. For these three reasons mismatches should be dealt with at the aggregated level and not at the individual level of each building. Instead, this paper suggests to compensate the mismatch of a building by increasing (or decreasing) the capacity...

  1. DNA triplet repeat expansion and mismatch repair.

    Science.gov (United States)

    Iyer, Ravi R; Pluciennik, Anna; Napierala, Marek; Wells, Robert D

    2015-01-01

    DNA mismatch repair is a conserved antimutagenic pathway that maintains genomic stability through rectification of DNA replication errors and attenuation of chromosomal rearrangements. Paradoxically, mutagenic action of mismatch repair has been implicated as a cause of triplet repeat expansions that cause neurological diseases such as Huntington disease and myotonic dystrophy. This mutagenic process requires the mismatch recognition factor MutSβ and the MutLα (and/or possibly MutLγ) endonuclease, and is thought to be triggered by the transient formation of unusual DNA structures within the expanded triplet repeat element. This review summarizes the current knowledge of DNA mismatch repair involvement in triplet repeat expansion, which encompasses in vitro biochemical findings, cellular studies, and various in vivo transgenic animal model experiments. We present current mechanistic hypotheses regarding mismatch repair protein function in mediating triplet repeat expansions and discuss potential therapeutic approaches targeting the mismatch repair pathway.

  2. Measurement of mismatch loss in CPV modul

    Science.gov (United States)

    Liu, Mingguo; Kinsey, Geoffrey S.; Bagienski, Will; Nayak, Adi; Garboushian, Vahan

    2012-10-01

    A setup capable of simultaneously measuring I-V curves of a full string and its individual cells has been developed. This setup enables us to measure mismatch loss from individual cells in concert with various string combinations under varying field conditions. Mismatch loss from cells to plates at different off-track angles and mismatch from plates to strings in Amonix system during normal operation have been investigated.

  3. Single base mismatches in the mRNA target site allow specific seed region-mediated off-target binding of siRNA targeting human coagulation factor 7.

    Science.gov (United States)

    Ravon, Morgane; Berrera, Marco; Ebeling, Martin; Certa, Ulrich

    2012-01-01

    We have analyzed the off-target activity of two siRNAs (F7-1, F7-2) that knock-down human blood coagulation factor 7 mRNA. F7-1 modulates a significant number of non-target transcripts while F7-2 shows high selectivity for the target transcript under various experimental conditions. The 3'-UTRs of all F7-1 off-target genes show statistically significant enrichment of the reverse complement of the F7-1 siRNA seed region located in the guide strand. Seed region enrichment was confirmed in off-target transcripts modulated by siRNA targeting the glucocorticoid receptor. To investigate how these sites contribute to off-target recognition of F7-1, we employed CXCL5 transcript as model system because it contains five F7-1 seed sequence motifs with single base mismatches. We show by transient transfection of reporter gene constructs into HEK293 cells that three out of five sites located in the 3'-UTR region are required for F7-1 off-target activity. For further mechanistic dissection, the sequences of these sites were synthesized and inserted either individually or joined in dimeric or trimeric constructs. Only the fusion constructs were silenced by F7-1 while the individual sites had no off-target activity. Based on F7-1 as a model, a single mismatch between the siRNA seed region and mRNA target sites is tolerated for target recognition and the CXCL5 data suggest a requirement for binding to multiple target sites in off-target transcripts.

  4. Global contrast based salient region detection

    KAUST Repository

    Cheng, Ming-Ming

    2011-08-25

    Reliable estimation of visual saliency allows appropriate processing of images without prior knowledge of their contents, and thus remains an important step in many computer vision tasks including image segmentation, object recognition, and adaptive compression. We propose a regional contrast based saliency extraction algorithm, which simultaneously evaluates global contrast differences and spatial coherence. The proposed algorithm is simple, efficient, and yields full resolution saliency maps. Our algorithm consistently outperformed existing saliency detection methods, yielding higher precision and better recall rates, when evaluated using one of the largest publicly available data sets. We also demonstrate how the extracted saliency map can be used to create high quality segmentation masks for subsequent image processing.

  5. Translating mismatch repair mechanism into cancer care.

    Science.gov (United States)

    Heinen, Christopher D

    2014-01-01

    The first DNA mismatch repair gene was identified in Escherichia coli nearly fifty years ago. Since then, five decades of basic biomedical research on this important repair pathway have led to an extensive understanding of its molecular mechanism. The significance of this work was clearly highlighted in the early 1990's when mutations in the human homologs of the mismatch repair genes were identified as responsible for Lynch syndrome (also known as hereditary non-polyposis colon cancer), the most common form of hereditary colorectal cancer. Basic science research on mismatch repair in lower organisms directly led researchers to the discovery of this link between defective mismatch repair and cancer and continues to guide clinical decisions today. The knowledge that disrupted mismatch repair function gives rise to the nucleotide-level form of genomic instability called microsatellite instability continues to be an important diagnostic tool for identifying Lynch syndrome patients as well as sporadic cancer patients who suffer from mismatch repairdefective cancers. Today, clinicians are using the information about mismatch repair molecular mechanism to guide decisions about cancer therapy as well to devise new therapies. In this review, we will examine what is known about the molecular function of the human mismatch repair pathway. We will highlight how this information is being used in cancer diagnosis and treatment. We will also discuss strategies being designed to target the 10-15% of colorectal, endometrial, ovarian and other cancers with defective mismatch repair.

  6. DNA & Protein detection based on microbead agglutination

    KAUST Repository

    Kodzius, Rimantas

    2012-06-06

    We report a simple and rapid room temperature assay for point-of-care (POC) testing that is based on specific agglutination. Agglutination tests are based on aggregation of microparticles in the presence of a specific analyte thus enabling the macroscopic observation. Agglutination-based tests are most often used to explore the antibody-antigen reactions. Agglutination has been used for mode protein assays using a biotin/streptavidin two-component system, as well as a hybridization based two-component assay; however, as our work shows, two-component systems are prone to self-termination of the linking analyte and thus have a lower sensitivity. Three component systems have also been used with DNA hybridization, as in our work; however, their assay requires 48 hours for incubation, while our assay is performed in 5 minutes making it a real candidate for POC testing. We demonstrate three assays: a two-component biotin/streptavidin assay, a three-component hybridization assay using single stranded DNA (ssDNA) molecules and a stepped three-component hybridization assay. The comparison of these three assays shows our simple stepped three-component agglutination assay to be rapid at room temperature and more sensitive than the two-component version by an order of magnitude. An agglutination assay was also performed in a PDMS microfluidic chip where agglutinated beads were trapped by filter columns for easy observation. We developed a rapid (5 minute) room temperature assay, which is based on microbead agglutination. Our three-component assay solves the linker self-termination issue allowing an order of magnitude increase in sensitivity over two–component assays. Our stepped version of the three-component assay solves the issue with probe site saturation thus enabling a wider range of detection. Detection of the agglutinated beads with the naked eye by trapping in microfluidic channels has been shown.

  7. Scene change detection based on multimodal integration

    Science.gov (United States)

    Zhu, Yingying; Zhou, Dongru

    2003-09-01

    Scene change detection is an essential step to automatic and content-based video indexing, retrieval and browsing. In this paper, a robust scene change detection and classification approach is presented, which analyzes audio, visual and textual sources and accounts for their inter-relations and coincidence to semantically identify and classify video scenes. Audio analysis focuses on the segmentation of audio stream into four types of semantic data such as silence, speech, music and environmental sound. Further processing on speech segments aims at locating speaker changes. Video analysis partitions visual stream into shots. Text analysis can provide a supplemental source of clues for scene classification and indexing information. We integrate the video and audio analysis results to identify video scenes and use the text information detected by the video OCR technology or derived from transcripts available to refine scene classification. Results from single source segmentation are in some cases suboptimal. By combining visual, aural features adn the accessorial text information, the scence extraction accuracy is enhanced, and more semantic segmentations are developed. Experimental results are proven to rather promising.

  8. Waveguide-Based Biosensors for Pathogen Detection

    Directory of Open Access Journals (Sweden)

    Nile Hartman

    2009-07-01

    Full Text Available Optical phenomena such as fluorescence, phosphorescence, polarization, interference and non-linearity have been extensively used for biosensing applications. Optical waveguides (both planar and fiber-optic are comprised of a material with high permittivity/high refractive index surrounded on all sides by materials with lower refractive indices, such as a substrate and the media to be sensed. This arrangement allows coupled light to propagate through the high refractive index waveguide by total internal reflection and generates an electromagnetic wave—the evanescent field—whose amplitude decreases exponentially as the distance from the surface increases. Excitation of fluorophores within the evanescent wave allows for sensitive detection while minimizing background fluorescence from complex, “dirty” biological samples. In this review, we will describe the basic principles, advantages and disadvantages of planar optical waveguide-based biodetection technologies. This discussion will include already commercialized technologies (e.g., Corning’s EPIC® Ô, SRU Biosystems’ BIND™, Zeptosense®, etc. and new technologies that are under research and development. We will also review differing assay approaches for the detection of various biomolecules, as well as the thin-film coatings that are often required for waveguide functionalization and effective detection. Finally, we will discuss reverse-symmetry waveguides, resonant waveguide grating sensors and metal-clad leaky waveguides as alternative signal transducers in optical biosensing.

  9. BEPS Action 2: Neutralizing the Effects on Hybrid Mismatch Arrangements

    NARCIS (Netherlands)

    de Boer, R.; Marres, O.

    2015-01-01

    Curbing tax arbitrage is one of the main priorities of the Organization for Economic Cooperation and Development (OECD) (endorsed by the G20 and the G8) ever since the public debate on base erosion fully erupted. Neutralizing the effect of hybrid mismatch arrangements has become Action No. 2 of the

  10. Mismatch in Law School. NBER Working Paper No. 14275

    Science.gov (United States)

    Rothstein, Jesse; Yoon, Albert

    2008-01-01

    An important criticism of race-based higher education admission preferences is that they may hurt minority students who attend more selective schools than they would in the absence of such preferences. We categorize the non-experimental research designs available for the study of so-called "mismatch" effects and evaluate the likely biases in each.…

  11. Magnetic source localization of early visual mismatch response

    NARCIS (Netherlands)

    Susac, A.; Heslenfeld, D.J.; Huonker, R.; Supek, S.

    2014-01-01

    Previous studies have reported a visual analogue of the auditory mismatch negativity (MMN) response that is based on sensory memory. The neural generators and attention dependence of the visual MMN (vMMN) still remain unclear. We used magnetoencephalography (MEG) and spatio-temporal source

  12. Modelling Trial-by-Trial Changes in the Mismatch Negativity

    Science.gov (United States)

    Lieder, Falk; Daunizeau, Jean; Garrido, Marta I.; Friston, Karl J.; Stephan, Klaas E.

    2013-01-01

    The mismatch negativity (MMN) is a differential brain response to violations of learned regularities. It has been used to demonstrate that the brain learns the statistical structure of its environment and predicts future sensory inputs. However, the algorithmic nature of these computations and the underlying neurobiological implementation remain controversial. This article introduces a mathematical framework with which competing ideas about the computational quantities indexed by MMN responses can be formalized and tested against single-trial EEG data. This framework was applied to five major theories of the MMN, comparing their ability to explain trial-by-trial changes in MMN amplitude. Three of these theories (predictive coding, model adjustment, and novelty detection) were formalized by linking the MMN to different manifestations of the same computational mechanism: approximate Bayesian inference according to the free-energy principle. We thereby propose a unifying view on three distinct theories of the MMN. The relative plausibility of each theory was assessed against empirical single-trial MMN amplitudes acquired from eight healthy volunteers in a roving oddball experiment. Models based on the free-energy principle provided more plausible explanations of trial-by-trial changes in MMN amplitude than models representing the two more traditional theories (change detection and adaptation). Our results suggest that the MMN reflects approximate Bayesian learning of sensory regularities, and that the MMN-generating process adjusts a probabilistic model of the environment according to prediction errors. PMID:23436989

  13. A possible mechanism for exonuclease 1-independent eukaryotic mismatch repair

    Science.gov (United States)

    Kadyrov, Farid A.; Genschel, Jochen; Fang, Yanan; Penland, Elisabeth; Edelmann, Winfried; Modrich, Paul

    2009-01-01

    Mismatch repair contributes to genetic stability, and inactivation of the mammalian pathway leads to tumor development. Mismatch correction occurs by an excision-repair mechanism and has been shown to depend on the 5′ to 3′ hydrolytic activity exonuclease 1 (Exo1) in eukaryotic cells. However, genetic and biochemical studies have indicated that one or more Exo1-independent modes of mismatch repair also exist. We have analyzed repair of nicked circular heteroduplex DNA in extracts of Exo1-deficient mouse embryo fibroblast cells. Exo1-independent repair under these conditions is MutLα-dependent and requires functional integrity of the MutLα endonuclease metal-binding motif. In contrast to the Exo1-dependent reaction, we have been unable to detect a gapped excision intermediate in Exo1-deficient extracts when repair DNA synthesis is blocked. A possible explanation for this finding has been provided by analysis of a purified system comprised of MutSα, MutLα, replication factor C, proliferating cell nuclear antigen, replication protein A, and DNA polymerase δ that supports Exo1-independent repair in vitro. Repair in this system depends on MutLα incision of the nicked heteroduplex strand and dNTP-dependent synthesis-driven displacement of a DNA segment spanning the mismatch. Such a mechanism may account, at least in part, for the Exo1-independent repair that occurs in eukaryotic cells, and hence the modest cancer predisposition of Exo1-deficient mammalian cells. PMID:19420220

  14. Patient - implant dimension mismatch in total knee arthroplasty: Is it worth worrying? An Indian scenario.

    Science.gov (United States)

    Thilak, Jai; George, Melvin J

    2016-09-01

    The correct sizing of the components in both anteroposterior and mediolateral (ML) dimensions is crucial for the success of a total knee arthroplasty (TKA). The size of the implants selected is based on the intraoperative measurements. The currently used TKA implants available to us are based on morphometric measurements obtained from a Western/Caucasian population. Hence, the risk of component ML mismatch is more common in Asian sub-population, as they are of a smaller built and stature. This study aims to look into the following aspects agnitude of the ML mismatch between the femoral component and the patient's anatomical dimension, evaluation of gender variations in distal femur dimensions, and gender-wise and implant-wise correlation of ML mismatch. Intraoperatively, the distal femoral dimensions were measured using sterile calipers after removing the osteophytes and compared with the ML dimension of the implant used. ML mismatch length thus obtained is correlated with the various parameters. Males showed larger distal femoral dimensions when compared to females. Males had larger ML mismatch. None of the implants used perfectly matched the patient's anatomical dimensions. Patients with larger mismatch had lower scorings at 2 years postoperative followup. Implant manufacturers need to design more options of femoral implants for a better fit in our subset of patients. The exact magnitude of mismatch which can cause functional implications need to be made out. The mismatch being one of the important factors for the success of the surgery, we should focus more on this aspect.

  15. Physiochemical disparity of mismatched HLA class I alloantigens and risk of acute GVHD following HSCT.

    Science.gov (United States)

    Kosmoliaptsis, V; Jöris, M M; Mallon, D H; Lankester, A C; von dem Borne, P A; Kuball, J; Bierings, M; Cornelissen, J J; Groenendijk-Sijnke, M E; van der Holt, B; Bradley, J A; Oudshoorn, M; van Rood, J J; Taylor, C J; Claas, F H J

    2015-04-01

    We determined whether assessment of the immunogenicity of individual donor-recipient HLA mismatches based on differences in their amino-acid sequence and physiochemical properties predicts clinical outcome following haematopoietic SCT (HSCT). We examined patients transplanted with 9/10 single HLA class I-mismatched grafts (n=171) and 10/10 HLA-A-, -B-, -C-, -DRB1- and -DQB1-matched grafts (n=168). A computer algorithm was used to determine the physiochemical disparity (electrostatic mismatch score (EMS) and hydrophobic mismatch score (HMS)) of mismatched HLA class I specificities in the graft-versus-host direction. Patients transplanted with HLA-mismatched grafts with high EMS/HMS had increased incidence of ⩾grade II acute GVHD (aGVHD) compared with patients transplanted with low EMS/HMS grafts; patients transplanted with low and medium EMS/HMS grafts had similar incidence of aGVHD to patients transplanted with 10/10 HLA-matched grafts. Mortality was higher following single HLA-mismatched HSCT but was not correlated with HLA physiochemical disparity. Assessment of donor-recipient HLA incompatibility based on physiochemical HLA disparity may enable better selection of HLA-mismatched donors in HSCT.

  16. Attribute and topology based change detection in a constellation of previously detected objects

    Science.gov (United States)

    Paglieroni, David W.; Beer, Reginald N.

    2016-01-19

    A system that applies attribute and topology based change detection to networks of objects that were detected on previous scans of a structure, roadway, or area of interest. The attributes capture properties or characteristics of the previously detected objects, such as location, time of detection, size, elongation, orientation, etc. The topology of the network of previously detected objects is maintained in a constellation database that stores attributes of previously detected objects and implicitly captures the geometrical structure of the network. A change detection system detects change by comparing the attributes and topology of new objects detected on the latest scan to the constellation database of previously detected objects.

  17. Mismatch repair deficiency testing in clinical practice.

    Science.gov (United States)

    Buza, Natalia; Ziai, James; Hui, Pei

    2016-01-01

    Lynch syndrome, an autosomal dominant inherited disorder, is caused by inactivating mutations involving DNA mismatch repair (MMR) genes. This leads to profound genetic instability, including microsatellite instability (MSI) and increased risk for cancer development, particularly colon and endometrial malignancies. Clinical testing of tumor tissues for the presence of MMR gene deficiency is standard practice in clinical oncology, with immunohistochemistry and PCR-based microsatellite instability analysis used as screening tests to identify potential Lynch syndrome families. The ultimate diagnosis of Lynch syndrome requires documentation of mutation within one of the four MMR genes (MLH1, PMS2, MSH2 and MSH6) or EPCAM, currently achieved by comprehensive sequencing analysis of germline DNA. In this review, the genetic basis of Lynch syndrome, methodologies of MMR deficiency testing, and current diagnostic algorithms in the clinical management of Lynch syndrome, are discussed.

  18. A neurocomputational model of the mismatch negativity.

    Directory of Open Access Journals (Sweden)

    Falk Lieder

    Full Text Available The mismatch negativity (MMN is an event related potential evoked by violations of regularity. Here, we present a model of the underlying neuronal dynamics based upon the idea that auditory cortex continuously updates a generative model to predict its sensory inputs. The MMN is then modelled as the superposition of the electric fields evoked by neuronal activity reporting prediction errors. The process by which auditory cortex generates predictions and resolves prediction errors was simulated using generalised (Bayesian filtering--a biologically plausible scheme for probabilistic inference on the hidden states of hierarchical dynamical models. The resulting scheme generates realistic MMN waveforms, explains the qualitative effects of deviant probability and magnitude on the MMN - in terms of latency and amplitude--and makes quantitative predictions about the interactions between deviant probability and magnitude. This work advances a formal understanding of the MMN and--more generally--illustrates the potential for developing computationally informed dynamic causal models of empirical electromagnetic responses.

  19. The nature of the transition mismatches with Watson-Crick architecture: the G*·T or G·T* DNA base mispair or both? A QM/QTAIM perspective for the biological problem.

    Science.gov (United States)

    Brovarets', Ol'ha O; Hovorun, Dmytro M

    2015-01-01

    This study provides the first accurate investigation of the tautomerization of the biologically important guanine*·thymine (G*·T) DNA base mispair with Watson-Crick geometry, involving the enol mutagenic tautomer of the G and the keto tautomer of the T, into the G·T* mispair (∆G = .99 kcal mol(-1), population = 15.8% obtained at the MP2 level of quantum-mechanical theory in the continuum with ε = 4), formed by the keto tautomer of the G and the enol mutagenic tautomer of the T base, using DFT and MP2 methods in vacuum and in the weakly polar medium (ε = 4), characteristic for the hydrophobic interfaces of specific protein-nucleic acid interactions. We were first able to show that the G*·T↔G·T* tautomerization occurs through the asynchronous concerted double proton transfer along two antiparallel O6H···O4 and N1···HN3 H-bonds and is assisted by the third N2H···O2 H-bond, that exists along the entire reaction pathway. The obtained results indicate that the G·T* base mispair is stable from the thermodynamic point of view complex, while it is dynamically unstable structure in vacuum and dynamically stable structure in the continuum with ε = 4 with lifetime of 6.4·10(-12) s, that, on the one side, makes it possible to develop all six low-frequency intermolecular vibrations, but, on the other side, it is by three orders less than the time (several ns) required for the replication machinery to forcibly dissociate a base pair into the monomers during DNA replication. One of the more significant findings to emerge from this study is that the short-lived G·T* base mispair, which electronic interaction energy between the bases (-23.76 kcal mol(-1)) exceeds the analogical value for the G·C Watson-Crick nucleobase pair (-20.38 kcal mol(-1)), "escapes from the hands" of the DNA replication machinery by fast transforming into the G*·T mismatch playing an indirect role of its supplier during the DNA replication. So

  20. Selective nanoscale growth of lattice mismatched materials

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung-Chang; Brueck, Steven R. J.

    2017-06-20

    Exemplary embodiments provide materials and methods of forming high-quality semiconductor devices using lattice-mismatched materials. In one embodiment, a composite film including one or more substantially-single-particle-thick nanoparticle layers can be deposited over a substrate as a nanoscale selective growth mask for epitaxially growing lattice-mismatched materials over the substrate.

  1. Approaches for Language Identification in Mismatched Environments

    Science.gov (United States)

    2016-09-08

    domain adaptation, unsupervised learning , deep neural networks, bottleneck features 1. Introduction and task Spoken language identification (LID) is...Approaches for Language Identification in Mismatched Environments Shahan Nercessian, Pedro Torres-Carrasquillo, and Gabriel Martínez-Montes...consider the task of language identification in the context of mismatch conditions. Specifically, we address the issue of using unlabeled data in the

  2. A buffer overflow detection based on inequalities solution

    International Nuclear Information System (INIS)

    Xu Guoai; Zhang Miao; Yang Yixian

    2007-01-01

    A new buffer overflow detection model based on Inequalities Solution was designed, which is based on analyzing disadvantage of the old buffer overflow detection technique and successfully converting buffer overflow detection to Inequalities Solution. The new model can conquer the disadvantage of the old technique and improve efficiency of buffer overflow detection. (authors)

  3. Discriminating DNA mismatches by electrochemical and gravimetric techniques.

    Science.gov (United States)

    Mazouz, Zouhour; Fourati, Najla; Zerrouki, Chouki; Ommezine, Asma; Rebhi, Lamia; Yaakoubi, Nourdin; Kalfat, Rafik; Othmane, Ali

    2013-10-15

    A silicon nitride functionalized electrode and a 104 MHz lithium tantalate (LiTaO₃) surface acoustic wave (SAW) sensor have been used to investigate target-probe recognition processes. Electrochemical and gravimetric measurements have been considered to monitor hybridization of single base mismatch (SBM) in synthetic oligonucleotides and single-nucleotide polymorphisms ApoE in real clinical genotypes. Obvious discrimination of SBM in nucleotides has been shown by both gravimetric and electrochemical techniques, without labeling nor amplification. Investigations on mismatches nature and position have also been considered. For guanine-adenine (GA), guanine-thymine (GT) and guanine-guanine (GG) mismatches, the sensors responses present a dependence upon positions. Considering the capacitance variations and hybridization rates, results showed that gravimetric transduction is more sensitive than electrochemical one. Moreover, the highest value of GT hybridization rate (in the middle position) was found in accordance with the nearest-neighbor model, where the considered configuration appears as the most thermodynamically stable. For the real samples, where the electrochemical transduction, by combining capacitance and flat-band potential measurements, were found more sensitive, the results show that the realized sensor permits an unambiguous discrimination of recognition between fully complementary, non-complementary and single base mismatched targets, and even between the combination of differently matched strands. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Lower incidence of acute GVHD is associated with the rapid recovery of CD4+CD25+CD45RA+ regulatory T cells in patients who received haploidentical allografts from NIMA-mismatched donors: A retrospective (development) and prospective (validation) cohort-based study.

    Science.gov (United States)

    Wang, Yu; Zhao, Xiang-Yu; Xu, Lan-Ping; Zhang, Xiao-Hui; Han, Wei; Chen, Huan; Wang, Feng-Rong; Mo, Xiao-Dong; Zhang, Yuan-Yuan; Zhao, Xiao-Su; Y, Kong; Liua, Kai-Yan; Huang, Xiao-Jun; Yu, Xue-Zhong; Chang, Ying-Jun

    2016-01-01

    To investigate the effects of non-inherited maternal antigen (NIMA) on clinical outcomes and immune recovery, especially of regulatory T cells (Tregs), in patients who underwent unmanipulated haploidentical transplantation. A retrospective cohort (n = 57) and a prospective cohort (n = 88) were included. All patients received haploidentical allografts from sibling donors. Reconstitution of immune subsets, including Tregs, was determined using multicolor flow cytometry. In the retrospective cohort, the cumulative incidence of grades II-IV acute GVHD in patients with NIMA-mismatched donors was significantly lower than that of cases with NIPA-mismatched donors (14.8% vs. 43.30%, p = 0.018). Patients with higher percentages of CD4 + CD25 + CD45RA + T cells (naive Tregs) within CD4 + T cells recovered on day 30 (≥1.55%) experienced a significantly lower incidence of grades II-IV acute GVHD than that of cases with lower percentages of naive Tregs (<1.55%) (13.8% vs. 46.4%, p = 0.010). Multivariate analysis showed that NIMA mismatch and the percentages of naive Tregs were associated with the incidence of grades II-IV acute GVHD [ p = 0.050, and 0.031, respectively]. In the prospective cohort, the association of NIMA mismatch [HR = 0.365, 95% CI, 0.169-0.786, p = 0.010] or higher percentages of naive Tregs recovered on day 30 (≥1.55%) [HR = 0.114, 95% CI, 0.027-0.479, p = 0.003] with a lower cumulative incidence of grades II-IV acute GVHD was further demonstrated. No effects of NIMA mismatch on chronic GVHD, transplant-related mortality, relapse, disease-free survival, or overall survival were found. Our results confirmed the role of NIMA mismatch in acute GVHD and provided the first demonstration, based on clinical data, that recovered Tregs may be involved in the effects of NIMA on acute GVHD in a haploidentical transplant setting.

  5. Smell Detection Agent Based Optimization Algorithm

    Science.gov (United States)

    Vinod Chandra, S. S.

    2016-09-01

    In this paper, a novel nature-inspired optimization algorithm has been employed and the trained behaviour of dogs in detecting smell trails is adapted into computational agents for problem solving. The algorithm involves creation of a surface with smell trails and subsequent iteration of the agents in resolving a path. This algorithm can be applied in different computational constraints that incorporate path-based problems. Implementation of the algorithm can be treated as a shortest path problem for a variety of datasets. The simulated agents have been used to evolve the shortest path between two nodes in a graph. This algorithm is useful to solve NP-hard problems that are related to path discovery. This algorithm is also useful to solve many practical optimization problems. The extensive derivation of the algorithm can be enabled to solve shortest path problems.

  6. Detecting Soft Errors in Stencil based Computations

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, V. [Univ. of Utah, Salt Lake City, UT (United States); Gopalkrishnan, G. [Univ. of Utah, Salt Lake City, UT (United States); Bronevetsky, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-05-06

    Given the growing emphasis on system resilience, it is important to develop software-level error detectors that help trap hardware-level faults with reasonable accuracy while minimizing false alarms as well as the performance overhead introduced. We present a technique that approaches this idea by taking stencil computations as our target, and synthesizing detectors based on machine learning. In particular, we employ linear regression to generate computationally inexpensive models which form the basis for error detection. Our technique has been incorporated into a new open-source library called SORREL. In addition to reporting encouraging experimental results, we demonstrate techniques that help reduce the size of training data. We also discuss the efficacy of various detectors synthesized, as well as our future plans.

  7. Bifunctional rhodium intercalator conjugates as mismatch-directing DNA alkylating agents.

    Science.gov (United States)

    Schatzschneider, Ulrich; Barton, Jacqueline K

    2004-07-21

    A conjugate of a DNA mismatch-specific rhodium intercalator, containing the bulky chrysenediimine ligand, and an aniline mustard has been prepared, and targeting of mismatches in DNA by this conjugate has been examined. The preferential alkylation of mismatched over fully matched DNA is found by a mobility shift assay at concentrations where untethered organic mustards show little reaction. The binding site of the Rh intercalator was determined by DNA photocleavage, and the position of covalent modification was established on the basis of the enhanced depurination associated with N-alkylation. The site-selective alkylation at mismatched DNA renders these conjugates useful tools for the covalent tagging of DNA base pair mismatches and new chemotherapeutic design.

  8. DNA Mismatch Repair and Oxidative DNA Damage: Implications for Cancer Biology and Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Bridge, Gemma; Rashid, Sukaina; Martin, Sarah A., E-mail: sarah.martin@qmul.ac.uk [Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ (United Kingdom)

    2014-08-05

    Many components of the cell, including lipids, proteins and both nuclear and mitochondrial DNA, are vulnerable to deleterious modifications caused by reactive oxygen species. If not repaired, oxidative DNA damage can lead to disease-causing mutations, such as in cancer. Base excision repair and nucleotide excision repair are the two DNA repair pathways believed to orchestrate the removal of oxidative lesions. However, recent findings suggest that the mismatch repair pathway may also be important for the response to oxidative DNA damage. This is particularly relevant in cancer where mismatch repair genes are frequently mutated or epigenetically silenced. In this review we explore how the regulation of oxidative DNA damage by mismatch repair proteins may impact on carcinogenesis. We discuss recent studies that identify potential new treatments for mismatch repair deficient tumours, which exploit this non-canonical role of mismatch repair using synthetic lethal targeting.

  9. DNA Mismatch Repair and Oxidative DNA Damage: Implications for Cancer Biology and Treatment

    International Nuclear Information System (INIS)

    Bridge, Gemma; Rashid, Sukaina; Martin, Sarah A.

    2014-01-01

    Many components of the cell, including lipids, proteins and both nuclear and mitochondrial DNA, are vulnerable to deleterious modifications caused by reactive oxygen species. If not repaired, oxidative DNA damage can lead to disease-causing mutations, such as in cancer. Base excision repair and nucleotide excision repair are the two DNA repair pathways believed to orchestrate the removal of oxidative lesions. However, recent findings suggest that the mismatch repair pathway may also be important for the response to oxidative DNA damage. This is particularly relevant in cancer where mismatch repair genes are frequently mutated or epigenetically silenced. In this review we explore how the regulation of oxidative DNA damage by mismatch repair proteins may impact on carcinogenesis. We discuss recent studies that identify potential new treatments for mismatch repair deficient tumours, which exploit this non-canonical role of mismatch repair using synthetic lethal targeting

  10. Single electron based binary multipliers with overflow detection ...

    African Journals Online (AJOL)

    electron based device. Multipliers with overflow detection based on serial and parallel prefix computation algorithm are elaborately discussed analytically and designed. The overflow detection circuits works in parallel with a simplified multiplier to ...

  11. Fault detection based on microseismic events

    Science.gov (United States)

    Yin, Chen

    2017-09-01

    In unconventional reservoirs, small faults allow the flow of oil and gas as well as act as obstacles to exploration; for, (1) fracturing facilitates fluid migration, (2) reservoir flooding, and (3) triggering of small earthquakes. These small faults are not generally detected because of the low seismic resolution. However, such small faults are very active and release sufficient energy to initiate a large number of microseismic events (MEs) during hydraulic fracturing. In this study, we identified microfractures (MF) from hydraulic fracturing and natural small faults based on microseismicity characteristics, such as the time-space distribution, source mechanism, magnitude, amplitude, and frequency. First, I identified the mechanism of small faults and MF by reservoir stress analysis and calibrated the ME based on the microseismic magnitude. The dynamic characteristics (frequency and amplitude) of MEs triggered by natural faults and MF were analyzed; moreover, the geometry and activity types of natural fault and MF were grouped according to the source mechanism. Finally, the differences among time-space distribution, magnitude, source mechanism, amplitude, and frequency were used to differentiate natural faults and manmade fractures.

  12. Hydrolytic function of Exo1 in mammalian mismatch repair

    Science.gov (United States)

    Shao, Hongbing; Baitinger, Celia; Soderblom, Erik J.; Burdett, Vickers; Modrich, Paul

    2014-01-01

    Genetic and biochemical studies have previously implicated exonuclease 1 (Exo1) in yeast and mammalian mismatch repair, with results suggesting that function of the protein in the reaction depends on both its hydrolytic activity and its ability to interact with other components of the repair system. However, recent analysis of an Exo1-E109K knockin mouse has concluded that Exo1 function in mammalian mismatch repair is restricted to a structural role, a conclusion based on a prior report that N-terminal His-tagged Exo1-E109K is hydrolytically defective. Because Glu-109 is distant from the nuclease hydrolytic center, we have compared the activity of untagged full-length Exo1-E109K with that of wild type Exo1 and the hydrolytically defective active site mutant Exo1-D173A. We show that the activity of Exo1-E109K is comparable to that of wild type enzyme in a conventional exonuclease assay and that in contrast to a D173A active site mutant, Exo1-E109K is fully functional in mismatch-provoked excision and repair. We conclude that the catalytic function of Exo1 is required for its participation in mismatch repair. We also consider the other phenotypes of the Exo1-E109K mouse in the context of Exo1 hydrolytic function. PMID:24829455

  13. Cellular telephone-based radiation detection instrument

    Energy Technology Data Exchange (ETDEWEB)

    Craig, William W [Pittsburg, CA; Labov, Simon E [Berkeley, CA

    2011-06-14

    A network of radiation detection instruments, each having a small solid state radiation sensor module integrated into a cellular phone for providing radiation detection data and analysis directly to a user. The sensor module includes a solid-state crystal bonded to an ASIC readout providing a low cost, low power, light weight compact instrument to detect and measure radiation energies in the local ambient radiation field. In particular, the photon energy, time of event, and location of the detection instrument at the time of detection is recorded for real time transmission to a central data collection/analysis system. The collected data from the entire network of radiation detection instruments are combined by intelligent correlation/analysis algorithms which map the background radiation and detect, identify and track radiation anomalies in the region.

  14. Mismatch repair and treatment resistance in ovarian cancer

    Directory of Open Access Journals (Sweden)

    van der Burg Maria EL

    2006-07-01

    Full Text Available Abstract Background The treatment of ovarian cancer is hindered by intrinsic or acquired resistance to platinum-based chemotherapy. The aim of this study is to determine the frequency of mismatch repair (MMR inactivation in ovarian cancer and its association with resistance to platinum-based chemotherapy. Methods We determined, microsatellite instability (MSI as a marker for MMR inactivation (analysis of BAT25 and BAT26, MLH1 promoter methylation status (methylation specific PCR on bisulfite treated DNA and mRNA expression of MLH1, MSH2, MSH3, MSH6 and PMS2 (quantitative RT-PCR in 75 ovarian carcinomas and eight ovarian cancer cell lines Results MSI was detected in three of the eight cell lines i.e. A2780 (no MLH1 mRNA expression due to promoter methylation, SKOV3 (no MLH1 mRNA expression and 2774 (no altered expression of MMR genes. Overall, there was no association between cisplatin response and MMR status in these eight cell lines. Seven of the 75 ovarian carcinomas showed MLH1 promoter methylation, however, none of these showed MSI. Forty-six of these patients received platinum-based chemotherapy (11 non-responders, 34 responders, one unknown response. The resistance seen in the eleven non-responders was not related to MSI and therefore also not to MMR inactivation. Conclusion No MMR inactivation was detected in 75 ovarian carcinoma specimens and no association was seen between MMR inactivation and resistance in the ovarian cancer cell lines as well as the ovarian carcinomas. In the discussion, the results were compared to that of twenty similar studies in the literature including in total 1315 ovarian cancer patients. Although no association between response and MMR status was seen in the primary tumor the possible role of MMR inactivation in acquired resistance deserves further investigation.

  15. Mismatch repair and treatment resistance in ovarian cancer

    International Nuclear Information System (INIS)

    Helleman, Jozien; Staveren, Iris L van; Dinjens, Winand NM; Kuijk, Patricia F van; Ritstier, Kirsten; Ewing, Patricia C; Burg, Maria EL van der; Stoter, Gerrit; Berns, Els MJJ

    2006-01-01

    The treatment of ovarian cancer is hindered by intrinsic or acquired resistance to platinum-based chemotherapy. The aim of this study is to determine the frequency of mismatch repair (MMR) inactivation in ovarian cancer and its association with resistance to platinum-based chemotherapy. We determined, microsatellite instability (MSI) as a marker for MMR inactivation (analysis of BAT25 and BAT26), MLH1 promoter methylation status (methylation specific PCR on bisulfite treated DNA) and mRNA expression of MLH1, MSH2, MSH3, MSH6 and PMS2 (quantitative RT-PCR) in 75 ovarian carcinomas and eight ovarian cancer cell lines MSI was detected in three of the eight cell lines i.e. A2780 (no MLH1 mRNA expression due to promoter methylation), SKOV3 (no MLH1 mRNA expression) and 2774 (no altered expression of MMR genes). Overall, there was no association between cisplatin response and MMR status in these eight cell lines. Seven of the 75 ovarian carcinomas showed MLH1 promoter methylation, however, none of these showed MSI. Forty-six of these patients received platinum-based chemotherapy (11 non-responders, 34 responders, one unknown response). The resistance seen in the eleven non-responders was not related to MSI and therefore also not to MMR inactivation. No MMR inactivation was detected in 75 ovarian carcinoma specimens and no association was seen between MMR inactivation and resistance in the ovarian cancer cell lines as well as the ovarian carcinomas. In the discussion, the results were compared to that of twenty similar studies in the literature including in total 1315 ovarian cancer patients. Although no association between response and MMR status was seen in the primary tumor the possible role of MMR inactivation in acquired resistance deserves further investigation

  16. Parametric Adaptive Radar Detector with Enhanced Mismatched Signals Rejection Capabilities

    Directory of Open Access Journals (Sweden)

    Liu Bin

    2010-01-01

    Full Text Available We consider the problem of adaptive signal detection in the presence of Gaussian noise with unknown covariance matrix. We propose a parametric radar detector by introducing a design parameter to trade off the target sensitivity with sidelobes energy rejection. The resulting detector merges the statistics of Kelly's GLRT and of the Rao test and so covers Kelly's GLRT and the Rao test as special cases. Both invariance properties and constant false alarm rate (CFAR behavior for this detector are studied. At the analysis stage, the performance of the new receiver is assessed and compared with several traditional adaptive detectors. The results highlight better rejection capabilities of this proposed detector for mismatched signals. Further, we develop two two-stage detectors, one of which consists of an adaptive matched filter (AMF followed by the aforementioned detector, and the other is obtained by cascading a GLRT-based Subspace Detector (SD and the proposed adaptive detector. We show that the former two-stage detector outperforms traditional two-stage detectors in terms of selectivity, and the latter yields more robustness.

  17. How Tolerant are Membrane Simulations with Mismatch in Area per Lipid between Leaflets?

    Science.gov (United States)

    Park, Soohyung; Beaven, Andrew H; Klauda, Jeffery B; Im, Wonpil

    2015-07-14

    Difficulties in estimating the correct number of lipids in each leaflet of complex bilayer membrane simulation systems make it inevitable to introduce a mismatch in lipid packing (i.e., area per lipid) and thus alter the lateral pressure of each leaflet. To investigate potential impacts of such mismatch on simulation results, we performed molecular dynamics simulations of saturated and monounsaturated lipid bilayers with and without gramicidin A or WALP23 at various mismatches by adjusting the number of lipids in the lower leaflet from no mismatch to a 25% reduction compared to that in the upper leaflet. All simulations were stable under the constant pressure barostat, but the mismatch induces asymmetric lipid packing between the leaflets, so that the upper leaflet becomes more ordered, and the lower leaflet becomes less ordered. The mismatch impacts on various bilayer properties are mild up to 5-10% mismatch, and bilayers with fully saturated chains appear to be more prone to these impacts than those with unsaturated tails. The nonvanishing leaflet surface tensions and the free energy derivatives with respect to the bilayer curvature indicate that the bilayer would be energetically unstable in the presence of mismatch. We propose a quantitative criterion for allowable mismatch based on the energetics derived from a continuum elastic model, which grows as a square root of the number of the lipids in the system. On the basis of this criterion, we infer that the area per lipid mismatch up to 5% would be tolerable in various membrane simulations of reasonable all-atom system sizes (40-160 lipids per leaflet).

  18. SKILLS MISMATCH OF THE YOUNG PEOPLE AT THE EUROPEAN LEVEL

    Directory of Open Access Journals (Sweden)

    Hatos Roxana

    2015-07-01

    Full Text Available Transition from school to work is a main issue with many fields of study. Studies on transition from school to work, have highlight the importance of two categories of factors at the level of the individual formal proceedings which may affect how easy it is to graduate to integrate into the labor market: 1 so far as the educational systems are transmitting specific competences as compared with those general and 2 so far as there are direct links between employers and the education system. In this way, are reduced the costs of selection and allocation for employers. A poor articulation between educational institutions and the labor market produce a high level of unmatched competences of assimilated by formal education and competencies required of the labor market (skill mismatch (Parodi et al., 2012. The surveys with European employers reflect particular difficulties that they are experiencing in employment vacancies. Investigation on the European companies in the spring of 2013 found that 40% of the firms in the EU have difficulty in finding employees with suitable qualification (CEDEFOP-European Center for the Development of the Vocational Training, 2014. Skills mismatch is a generic term that refers to various types of imbalances between skills and competences offered and those required in the labor market. Concept has become one intensely discussed and submitted to measurement in international research on the background concerns the under-utilization human resource. Numerous opinion polls with employers come to the same unexpected conclusion - that despite high unemployment many posts can't find occupants satisfactorily prepared and identify the causes: most of them criticized the lack of skills of the candidates or the absence of skills specific to the workplace. Based on the latest studies on international databases have built a set of questions that, through secondary analysis, we tried to find answers. Questions that we try to give answer

  19. Water Pollution Detection Based on Hypothesis Testing in Sensor Networks

    Directory of Open Access Journals (Sweden)

    Xu Luo

    2017-01-01

    Full Text Available Water pollution detection is of great importance in water conservation. In this paper, the water pollution detection problems of the network and of the node in sensor networks are discussed. The detection problems in both cases of the distribution of the monitoring noise being normal and nonnormal are considered. The pollution detection problems are analyzed based on hypothesis testing theory firstly; then, the specific detection algorithms are given. Finally, two implementation examples are given to illustrate how the proposed detection methods are used in the water pollution detection in sensor networks and prove the effectiveness of the proposed detection methods.

  20. Nonstationary weak signal detection based on normalization ...

    Indian Academy of Sciences (India)

    ... than the traditional stochastic resonance. The method develops the area of time-varying signal detection with stochastic resonance and presents new strategy for detection and denoising of a time-varying signal. It can be expected to be widely used in the areas of aperiodic signal processing, radar communication,etc ...

  1. Laser-Based Detection Methods for Explosives

    Science.gov (United States)

    2007-09-01

    Photofragmentation-Fragment Detection (SPF-FD) Cabalo and Sausa introduced a technique for detection of explosives with low vapor pressure called SPF-FD (149...1999, 38, 6447. 149. Cabalo , J.; Sausa, R. Appl. Spectrosc. 2003, 57, 1196. 150. Claspy, P. C.; Pao, Y.-H.; Kwong, S.; Nodov, E. IEEE J. Quant

  2. Network Anomaly Detection Based on Wavelet Analysis

    Directory of Open Access Journals (Sweden)

    Ali A. Ghorbani

    2008-11-01

    Full Text Available Signal processing techniques have been applied recently for analyzing and detecting network anomalies due to their potential to find novel or unknown intrusions. In this paper, we propose a new network signal modelling technique for detecting network anomalies, combining the wavelet approximation and system identification theory. In order to characterize network traffic behaviors, we present fifteen features and use them as the input signals in our system. We then evaluate our approach with the 1999 DARPA intrusion detection dataset and conduct a comprehensive analysis of the intrusions in the dataset. Evaluation results show that the approach achieves high-detection rates in terms of both attack instances and attack types. Furthermore, we conduct a full day's evaluation in a real large-scale WiFi ISP network where five attack types are successfully detected from over 30 millions flows.

  3. Visual mismatch and predictive coding: A computational single-trial ERP study.

    Science.gov (United States)

    Stefanics, Gabor; Heinzle, Jakob; Attila Horváth, András; Enno Stephan, Klaas

    2018-03-26

    Predictive coding (PC) posits that the brain employs a generative model to infer the environmental causes of its sensory data and uses precision-weighted prediction errors (pwPE) to continuously update this model. While supported by much circumstantial evidence, experimental tests grounded in formal trial-by-trial predictions are rare. One partial exception are event-related potential (ERP) studies of the auditory mismatch negativity (MMN), where computational models have found signatures of pwPEs and related model-updating processes.Here, we tested this hypothesis in the visual domain, examining possible links between visual mismatch responses and pwPEs. We used a novel visual 'roving standard' paradigm to elicit mismatch responses in humans (of both sexes) by unexpected changes in either color or emotional expression of faces. Using a hierarchical Bayesian model, we simulated pwPE trajectories of a Bayes-optimal observer and used these to conduct a comprehensive trial-by-trial analysis across the time×sensor space. We found significant modulation of brain activity by both color and emotion pwPEs. The scalp distribution and timing of these single-trial pwPE responses were in agreement with visual mismatch responses obtained by traditional averaging and subtraction (deviant-minus-standard) approaches. Finally, we compared the Bayesian model to a more classical change detection (CD) model of MMN. Model comparison revealed that trial-wise pwPEs explained the observed mismatch responses better than categorical change detection.Our results suggest that visual mismatch responses reflect trial-wise pwPEs, as postulated by PC. These findings go beyond classical ERP analyses of visual mismatch and illustrate the utility of computational analyses for studying automatic perceptual processes. SIGNIFICANCE STATEMENT Human perception is thought to rely on a predictive model of the environment which is updated via precision-weighted prediction errors (pwPE) when events violate

  4. A silicon-based electrochemical sensor for highly sensitive, specific, label-free and real-time DNA detection

    International Nuclear Information System (INIS)

    Guo, Yuanyuan; Su, Shao; Wei, Xinpan; Zhong, Yiling; Su, Yuanyuan; He, Yao; Huang, Qing; Fan, Chunhai

    2013-01-01

    We herein present a new kind of silicon-based electrochemical sensor using a gold nanoparticles-decorated silicon wafer (AuNPs@Si) as a high-performance electrode, which is facilely prepared via in situ AuNPs growth on a silicon wafer. Particularly significantly, the resultant electrochemical sensor is efficacious for label-free DNA detection with high sensitivity due to the unique merits of the prepared silicon-based electrode. Typically, DNA at remarkably low concentrations (1–10 fM) could be readily detected without requiring additional signal-amplification procedures, which is better than or comparable to the lowest DNA concentration ever detected via well-studied signal-amplification-assisted electrochemical sensors. Moreover, the silicon-based sensor features high specificity, allowing unambiguous discrimination of single-based mismatches. We further show that real-time DNA assembly is readily monitored via recording the intensity changes of current signals due to the robust thermal stability of the silicon-based electrode. The unprecedented advantages of the silicon-based electrochemical sensor would offer new opportunities for myriad sensing applications. (paper)

  5. Preventing Tax arbitrage via Hybrid Mismatches: BEPS Action 2 and Developing Countries

    OpenAIRE

    Kuzniacki, Blazej; Turina, Alessandro; Dubut, Thomas; Mazz, Addy; Quiñones, Natalia; Schoueri, Luís Eduardo; West, Craig; Pistone, Pasquale; Zimmer, Frederik

    2017-01-01

    The Organization for Economic Cooperation and Development (OECD) under Base Erosion and Profit Shifting (BEPS) Action 2 indicated that tax arbitrage via hybrid mismatch arrangements "result in a substantial erosion of the taxable bases of the countries concerned" and "have an overall negative impact on competition, efficiency, transparency and fairness." The relevant action allowing for neutralising the effects of hybrid mismatch arrangements is therefore needed and justified. To ...

  6. Anomica: Fast Support Vector Based Novelty Detection

    Data.gov (United States)

    National Aeronautics and Space Administration — In this paper we propose ν-Anomica, a novel anomaly detection technique that can be trained on huge data sets with much reduced running time compared to the...

  7. New insights into the mechanism of DNA mismatch repair

    Science.gov (United States)

    Reyes, Gloria X.; Schmidt, Tobias T.; Kolodner, Richard D.; Hombauer, Hans

    2015-01-01

    The genome of all organisms is constantly being challenged by endogenous and exogenous sources of DNA damage. Errors like base:base mismatches or small insertions and deletions, primarily introduced by DNA polymerases during DNA replication are repaired by an evolutionary conserved DNA mismatch repair (MMR) system. The MMR system, together with the DNA replication machinery, promote repair by an excision and resynthesis mechanism during or after DNA replication, increasing replication fidelity by upto-three orders of magnitude. Consequently, inactivation of MMR genes results in elevated mutation rates that can lead to increased cancer susceptibility in humans. In this review, we summarize our current understanding of MMR with a focus on the different MMR protein complexes, their function and structure. We also discuss how recent findings have provided new insights in the spatio-temporal regulation and mechanism of MMR. PMID:25862369

  8. Lattice Mismatch in Crystalline Nanoparticle Thin Films.

    Science.gov (United States)

    Gabrys, Paul A; Seo, Soyoung E; Wang, Mary X; Oh, EunBi; Macfarlane, Robert J; Mirkin, Chad A

    2018-01-10

    For atomic thin films, lattice mismatch during heteroepitaxy leads to an accumulation of strain energy, generally causing the films to irreversibly deform and generate defects. In contrast, more elastically malleable building blocks should be better able to accommodate this mismatch and the resulting strain. Herein, that hypothesis is tested by utilizing DNA-modified nanoparticles as "soft," programmable atom equivalents to grow a heteroepitaxial colloidal thin film. Calculations of interaction potentials, small-angle X-ray scattering data, and electron microscopy images show that the oligomer corona surrounding a particle core can deform and rearrange to store elastic strain up to ±7.7% lattice mismatch, substantially exceeding the ±1% mismatch tolerated by atomic thin films. Importantly, these DNA-coated particles dissipate strain both elastically through a gradual and coherent relaxation/broadening of the mismatched lattice parameter and plastically (irreversibly) through the formation of dislocations or vacancies. These data also suggest that the DNA cannot be extended as readily as compressed, and thus the thin films exhibit distinctly different relaxation behavior in the positive and negative lattice mismatch regimes. These observations provide a more general understanding of how utilizing rigid building blocks coated with soft compressible polymeric materials can be used to control nano- and microstructure.

  9. A teleofunctional account of evolutionary mismatch.

    Science.gov (United States)

    Cofnas, Nathan

    When the environment in which an organism lives deviates in some essential way from that to which it is adapted, this is described as "evolutionary mismatch," or "evolutionary novelty." The notion of mismatch plays an important role, explicitly or implicitly, in evolution-informed cognitive psychology, clinical psychology, and medicine. The evolutionary novelty of our contemporary environment is thought to have significant implications for our health and well-being. However, scientists have generally been working without a clear definition of mismatch. This paper defines mismatch as deviations in the environment that render biological traits unable, or impaired in their ability, to produce their selected effects (i.e., to perform their proper functions in Neander's sense). The machinery developed by Millikan in connection with her account of proper function, and with her related teleosemantic account of representation, is used to identify four major types, and several subtypes, of evolutionary mismatch. While the taxonomy offered here does not in itself resolve any scientific debates, the hope is that it can be used to better formulate empirical hypotheses concerning the effects of mismatch. To illustrate, it is used to show that the controversial hypothesis that general intelligence evolved as an adaptation to handle evolutionary novelty can, contra some critics, be formulated in a conceptually coherent way.

  10. Attomolar detection of BRCA1 gene based on gold nanoparticle assisted signal amplification.

    Science.gov (United States)

    Abdul Rasheed, P; Sandhyarani, N

    2015-03-15

    In this work, we report a simple strategy for signal amplification using appropriately functionalized gold nanoparticles in an electrochemical genosensor which led to attomolar detection of breast cancer 1 (BRCA1) gene. The sensor was developed by the layer-by-layer assembly of mercaptopropionic acid (MPA), polyethylene glycol (PEG) functionalized gold nanoparticle (AuNPPEG), capture DNA (DNA-c), target BRCA1 DNA (DNA-t) and gold nanoparticle labeled reporter DNA (DNA-r.AuNP) on gold electrode. PEG functionalized gold nanoparticles on the MPA surface provided good electron conducting path nullifying the insulating effect of MPA and also act as a proper immobilization platform for the DNA-c by the large number of carboxyl groups present on the functionalized gold nanoparticles. We demonstrated that the incorporation of MPA functionalized gold nanoparticles (AuNPMPA) as an electrochemical label in this sensor design could significantly enhance the sensitivity in the detection. The DNA hybridization of DNA-r.AuNP with target probe was measured by chronoamperometry, electrochemical impedance spectroscopy (EIS), and scanning tunnelling spectroscopy (STS). Electrochemical quartz crystal microbalance (EQCM) experiments were used to support the detection and also to calculate the number of adsorbed molecules on the surface. Under optimum conditions the present sensor exhibited high sensitivity and a very low detection limit of 50attomolar DNA target (294.8attogram BRCA1gene/ml). It shows excellent selectivity against non complementary sequences and 3 base mismatch complementary targets. It also shows good reproducibility, stability and reusability and the developed sensor surface is suitable for point-of care applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. 49 CFR 213.115 - Rail end mismatch.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Rail end mismatch. 213.115 Section 213.115..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.115 Rail end mismatch. Any mismatch... mismatch of rails at joints may not be more than the following— On the tread of the rail ends (inch) On the...

  12. Circuit mismatch influence on performance of paralleling silicon carbide MOSFETs

    DEFF Research Database (Denmark)

    Li, Helong; Munk-Nielsen, Stig; Pham, Cam

    2014-01-01

    This paper focuses on circuit mismatch influence on performance of paralleling SiC MOSFETs. Power circuit mismatch and gate driver mismatch influences are analyzed in detail. Simulation and experiment results show the influence of circuit mismatch and verify the analysis. This paper aims to give...

  13. 49 CFR 213.349 - Rail end mismatch.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Rail end mismatch. 213.349 Section 213.349... Rail end mismatch. Any mismatch of rails at joints may not be more than that prescribed by the following table— Class of track Any mismatch of rails at joints may not be more than the following— On the...

  14. Addressing private sector currency mismatches in emerging Europe

    OpenAIRE

    Jeromin Zettelmeyer; Piroska M. Nagy; Stephen Jeffrey

    2010-01-01

    This paper provides a survey of the theoretical and empirical literature on the dollarisation of corporate and household liabilities; presents evidence on the causes of FX lending specifically in transition economies; and proposes a set of criteria to help decide on the right policy response based on country characteristics. These criteria particularly affect the extent to which regulation should be part of the policy response. Regulation to contain FX mismatches is useful in relatively advan...

  15. Mismatch negativity to pitch pattern deviants in schizophrenia.

    Science.gov (United States)

    Haigh, Sarah M; Matteis, Mario De; Coffman, Brian A; Murphy, Timothy K; Butera, Christiana D; Ward, Kayla L; Leiter-McBeth, Justin R; Salisbury, Dean F

    2017-09-01

    Simple mismatch negativity (MMN) to infrequent pitch deviants is impaired in individuals with long-term schizophrenia (Sz). The complex MMN elicited by pattern deviance often manifes is cut from here]->ts later after deviant onset than simple MMN and can ascertain deficits in abstracting relationships between stimuli. Sz exhibit reduced complex MMN, but so far this has only been measured when deviance detection relies on a grouping rule. We measured MMN to deviants in pitch-based rules to see whether MMN is also abnormal in Sz under these conditions. Three experiments were conducted. Twenty-seven Sz and 28 healthy matched controls (HC) participated in Experiments 1 and 2, and 24 Sz and 26 HC participated in Experiment 3. Experiment 1 was a standard pitch MMN task, and Sz showed the expected MMN reduction (~ 115 ms) in the simple pitch deviant compared to HC. Experiment 2 comprised standard groups of six tones that ascended in pitch, and deviant groups where the last tone descended in pitch. Complex MMN was late (~ 510 ms) and significantly blunted in Sz. Experiment 3 comprised standard groups of 12 tones (six tones ascending in pitch followed by six tones descending in pitch, like a scale), and deviant groups containing two repetitions of six ascending tones (the scale restarted midstream). Complex MMN was also late (~ 460 ms) and significantly blunted in Sz. These results identify a late pitch pattern deviance-related MMN that is deficient in schizophrenia. This suggests specific deficits in later more complex deviance detection in schizophrenia for abstract patterns. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  16. Evaluating Mismatch Repair Deficiency in Pancreatic Adenocarcinoma: Challenges and Recommendations.

    Science.gov (United States)

    Hu, Zishuo I; Shia, Jinru; Stadler, Zsofia K; Varghese, Anna M; Capanu, Marinela; Salo-Mullen, Erin; Lowery, Maeve A; Diaz, Luis A; Mandelker, Diana; Yu, Kenneth H; Zervoudakis, Alice; Kelsen, David P; Iacobuzio-Donahue, Christine A; Klimstra, David S; Saltz, Leonard B; Sahin, Ibrahim H; O'Reilly, Eileen M

    2018-01-24

    Purpose: Immune checkpoint inhibition has been shown to generate profound and durable responses in mismatch repair deficient (MMR-D) solid tumors and has elicited interest in detection tools and strategies to guide therapeutic decision-making. Herein we address questions on the appropriate screening, detection methods, patient selection, and initiation of therapy for MMR-D pancreatic ductal adenocarcinoma (PDAC) and assess the utility of next-generation sequencing (NGS) in providing additional prognostic and predictive information for MMR-D PDAC. Experimental Design: Archival and prospectively acquired samples and matched normal DNA from N = 833 PDAC cases were analyzed using a hybridization capture-based, NGS assay designed to perform targeted deep sequencing of all exons and selected introns of 341 to 468 cancer-associated genes. A computational program using NGS data derived the MSI status from the tumor-normal paired genome sequencing data. Available germline testing, IHC, and microsatellite instability (MSI) PCR results were reviewed to assess and confirm MMR-D and MSI status. Results: MMR-D in PDAC is a rare event among PDAC patients (7/833), occurring at a frequency of 0.8%. Loss of MMR protein expression by IHC, high mutational load, and elevated MSIsensor scores were correlated with MMR-D PDAC. All 7 MMR-D PDAC patients in the study were found to have Lynch syndrome. Four (57%) of the MMR-D patients treated with immune checkpoint blockade had treatment benefit (1 complete response, 2 partial responses, 1 stable disease). Conclusions: An integrated approach of germline testing and somatic analyses of tumor tissues in advanced PDAC using NGS may help guide future development of immune and molecularly directed therapies in PDAC patients. Clin Cancer Res; 24(6); 1-11. ©2018 AACR. ©2018 American Association for Cancer Research.

  17. Blind ICA detection based on second-order cone programming for MC-CDMA systems

    Science.gov (United States)

    Jen, Chih-Wei; Jou, Shyh-Jye

    2014-12-01

    The multicarrier code division multiple access (MC-CDMA) technique has received considerable interest for its potential application to future wireless communication systems due to its high data rate. A common problem regarding the blind multiuser detectors used in MC-CDMA systems is that they are extremely sensitive to the complex channel environment. Besides, the perturbation of colored noise may negatively affect the performance of the system. In this paper, a new coherent detection method will be proposed, which utilizes the modified fast independent component analysis (FastICA) algorithm, based on approximate negentropy maximization that is subject to the second-order cone programming (SOCP) constraint. The aim of the proposed coherent detection is to provide robustness against small-to-medium channel estimation mismatch (CEM) that may arise from channel frequency response estimation error in the MC-CDMA system, which is modulated by downlink binary phase-shift keying (BPSK) under colored noise. Noncoherent demodulation schemes are preferable to coherent demodulation schemes, as the latter are difficult to implement over time-varying fading channels. Differential phase-shift keying (DPSK) is therefore the natural choice for an alternative modulation scheme. Furthermore, the new blind differential SOCP-based ICA (SOCP-ICA) detection without channel estimation and compensation will be proposed to combat Doppler spread caused by time-varying fading channels in the DPSK-modulated MC-CDMA system under colored noise. In this paper, numerical simulations are used to illustrate the robustness of the proposed blind coherent SOCP-ICA detector against small-to-medium CEM and to emphasize the advantage of the blind differential SOCP-ICA detector in overcoming Doppler spread.

  18. An Entropy-Based Network Anomaly Detection Method

    Directory of Open Access Journals (Sweden)

    Przemysław Bereziński

    2015-04-01

    Full Text Available Data mining is an interdisciplinary subfield of computer science involving methods at the intersection of artificial intelligence, machine learning and statistics. One of the data mining tasks is anomaly detection which is the analysis of large quantities of data to identify items, events or observations which do not conform to an expected pattern. Anomaly detection is applicable in a variety of domains, e.g., fraud detection, fault detection, system health monitoring but this article focuses on application of anomaly detection in the field of network intrusion detection.The main goal of the article is to prove that an entropy-based approach is suitable to detect modern botnet-like malware based on anomalous patterns in network. This aim is achieved by realization of the following points: (i preparation of a concept of original entropy-based network anomaly detection method, (ii implementation of the method, (iii preparation of original dataset, (iv evaluation of the method.

  19. Vision-based vehicle detection and tracking algorithm design

    Science.gov (United States)

    Hwang, Junyeon; Huh, Kunsoo; Lee, Donghwi

    2009-12-01

    The vision-based vehicle detection in front of an ego-vehicle is regarded as promising for driver assistance as well as for autonomous vehicle guidance. The feasibility of vehicle detection in a passenger car requires accurate and robust sensing performance. A multivehicle detection system based on stereo vision has been developed for better accuracy and robustness. This system utilizes morphological filter, feature detector, template matching, and epipolar constraint techniques in order to detect the corresponding pairs of vehicles. After the initial detection, the system executes the tracking algorithm for the vehicles. The proposed system can detect front vehicles such as the leading vehicle and side-lane vehicles. The position parameters of the vehicles located in front are obtained based on the detection information. The proposed vehicle detection system is implemented on a passenger car, and its performance is verified experimentally.

  20. Mismatch discrimination of lipidated DNA and LNA-probes (LiNAs) in hybridization-controlled liposome assembly

    DEFF Research Database (Denmark)

    Jakobsen, Ulla; Vogel, Stefan

    2016-01-01

    nucleic acids) probe designs, including membrane-anchoring requirements, studies on different probes and target lengths (including overhangs), DNA and RNA targets (including sequences associated with pathogens) for lipidated nucleic acids (LiNAs). Advantages and limitations of the liposome assembly based...... assay in the context of mismatch discrimination and SNP detection are presented. The advantages of membrane-anchored LiNA-probes compared to chemically attached probes on solid nanoparticles (e.g. gold nanoparticles) are described. Key functionalities such as non-covalent attachment of LiNA probes...

  1. Nanopore-Based Target Sequence Detection.

    Directory of Open Access Journals (Sweden)

    Trevor J Morin

    Full Text Available The promise of portable diagnostic devices relies on three basic requirements: comparable sensitivity to established platforms, inexpensive manufacturing and cost of operations, and the ability to survive rugged field conditions. Solid state nanopores can meet all these requirements, but to achieve high manufacturing yields at low costs, assays must be tolerant to fabrication imperfections and to nanopore enlargement during operation. This paper presents a model for molecular engineering techniques that meets these goals with the aim of detecting target sequences within DNA. In contrast to methods that require precise geometries, we demonstrate detection using a range of pore geometries. As a result, our assay model tolerates any pore-forming method and in-situ pore enlargement. Using peptide nucleic acid (PNA probes modified for conjugation with synthetic bulk-adding molecules, pores ranging 15-50 nm in diameter are shown to detect individual PNA-bound DNA. Detection of the CFTRΔF508 gene mutation, a codon deletion responsible for ∼66% of all cystic fibrosis chromosomes, is demonstrated with a 26-36 nm pore size range by using a size-enhanced PNA probe. A mathematical framework for assessing the statistical significance of detection is also presented.

  2. Adaptive skin detection based on online training

    Science.gov (United States)

    Zhang, Ming; Tang, Liang; Zhou, Jie; Rong, Gang

    2007-11-01

    Skin is a widely used cue for porn image classification. Most conventional methods are off-line training schemes. They usually use a fixed boundary to segment skin regions in the images and are effective only in restricted conditions: e.g. good lightness and unique human race. This paper presents an adaptive online training scheme for skin detection which can handle these tough cases. In our approach, skin detection is considered as a classification problem on Gaussian mixture model. For each image, human face is detected and the face color is used to establish a primary estimation of skin color distribution. Then an adaptive online training algorithm is used to find the real boundary between skin color and background color in current image. Experimental results on 450 images showed that the proposed method is more robust in general situations than the conventional ones.

  3. Laser spot detection based on reaction diffusion

    Czech Academy of Sciences Publication Activity Database

    Vázquez-Otero, Alejandro; Khikhlukha, Danila; Solano-Altamirano, J. M.; Dormido, R.; Duro, N.

    2016-01-01

    Roč. 16, č. 3 (2016), s. 1-11, č. článku 315. ISSN 1424-8220 R&D Projects: GA MŠk EF15_008/0000162 Grant - others:ELI Beamlines(XE) CZ.02.1.01/0.0/0.0/15_008/0000162 Institutional support: RVO:68378271 Keywords : laser spot detection * laser beam detection * reaction diffusion models * Fitzhugh-Nagumo model * reaction diffusion computation * Turing patterns Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 2.677, year: 2016

  4. Enhanced sensing of dengue virus DNA detection using O2plasma treated-silicon nanowire based electrical biosensor.

    Science.gov (United States)

    Rahman, S F A; Yusof, N A; Hashim, U; Hushiarian, R; M N, M Nuzaihan; Hamidon, M N; Zawawi, R M; Fathil, M F M

    2016-10-26

    Dengue Virus (DENV) has become one of the most serious arthropod-borne viral diseases, causing death globally. The existing methods for DENV detection suffer from the late stage treatment due to antibodies-based detection which is feasible only after five days following the onset of the illness. Here, we demonstrated the highly effective molecular electronic based detection utilizing silicon nanowire (SiNW) integrated with standard complementary metal-oxide-semiconductor (CMOS) process as a sensing device for detecting deoxyribonucleic acid (DNA) related to DENV in an early stage diagnosis. To transform the fabricated devices as a functional sensing element, three-step procedure consist of SiNW surface modification, DNA immobilization and DNA hybridization were employed. The detection principle works by detecting the changes in current of SiNW which bridge the source and drain terminal to sense the immobilization of probe DNA and their hybridization with target DNA. The oxygen (O 2 ) plasma was proposed as an effective strategy for increasing the binding amounts of target DNA by modified the SiNW surface. It was found that the detection limit of the optimized O 2 plasma treated-SiNW device could be reduced to 1.985 × 10 -14  M with a linear detection range of the sequence-specific DNA from 1.0 × 10 -9  M to 1.0 × 10 -13  M. In addition, the developed biosensor device was able to discriminate between complementary, single mismatch and non-complementary DNA sequences. This highly sensitive assay was then applied to the detection of reverse transcription-polymerase chain reaction (RT-PCR) product of DENV-DNA, making it as a potential method for disease diagnosis through electrical biosensor. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. How Useful Is the Concept of Skills Mismatch?

    OpenAIRE

    McGuinness, Seamus; Pouliakas, Konstantinos; Redmond, Paul

    2017-01-01

    The term skill mismatch is very broad and can relate to many forms of labour market friction, including vertical mismatch, skill gaps, skill shortages, field of study (horizontal) mismatch and skill obsolescence. In this paper we provide a clear overview of each concept and discuss the measurement and inter-relatedness of different forms of mismatch. We present a comprehensive analysis of the current position of the literature on skills mismatch and highlight areas which are relatively underd...

  6. The design method and research status of vehicle detection system based on geomagnetic detection principle

    Science.gov (United States)

    Lin, Y. H.; Bai, R.; Qian, Z. H.

    2018-03-01

    Vehicle detection systems are applied to obtain real-time information of vehicles, realize traffic control and reduce traffic pressure. This paper reviews geomagnetic sensors as well as the research status of the vehicle detection system. Presented in the paper are also our work on the vehicle detection system, including detection algorithms and experimental results. It is found that the GMR based vehicle detection system has a detection accuracy up to 98% with a high potential for application in the road traffic control area.

  7. Contour Detection Operators Based on Surround Inhibition

    NARCIS (Netherlands)

    Grigorescu, Cosmin; Petkov, Nicolai; Westenberg, Michel A.

    2003-01-01

    We propose a biologically motivated computational step, called non-classical receptive field (non-CRF) inhibition, to improve contour detection in images of natural scenes. We augment a Gabor energy operator with non-CRF inhibition. The resulting contour operator responds strongly to isolated lines,

  8. Nonstationary weak signal detection based on normalization ...

    Indian Academy of Sciences (India)

    Haibin Zhang

    Time-varying signal; weak signal detection; varying parameters; stochastic resonance. 1. Introduction. In general view, noise ..... the numerical solution for the typical first-order differential equation as Eq. (2). The discrete fourth-rank Runge–Kutta method [27] as follows is applied to solve the equation numerically. x. 0 ¼ dx dt.

  9. Visual-perceptual mismatch in robotic surgery.

    Science.gov (United States)

    Abiri, Ahmad; Tao, Anna; LaRocca, Meg; Guan, Xingmin; Askari, Syed J; Bisley, James W; Dutson, Erik P; Grundfest, Warren S

    2017-08-01

    The principal objective of the experiment was to analyze the effects of the clutch operation of robotic surgical systems on the performance of the operator. The relative coordinate system introduced by the clutch operation can introduce a visual-perceptual mismatch which can potentially have negative impact on a surgeon's performance. We also assess the impact of the introduction of additional tactile sensory information on reducing the impact of visual-perceptual mismatch on the performance of the operator. We asked 45 novice subjects to complete peg transfers using the da Vinci IS 1200 system with grasper-mounted, normal force sensors. The task involves picking up a peg with one of the robotic arms, passing it to the other arm, and then placing it on the opposite side of the view. Subjects were divided into three groups: aligned group (no mismatch), the misaligned group (10 cm z axis mismatch), and the haptics-misaligned group (haptic feedback and z axis mismatch). Each subject performed the task five times, during which the grip force, time of completion, and number of faults were recorded. Compared to the subjects that performed the tasks using a properly aligned controller/arm configuration, subjects with a single-axis misalignment showed significantly more peg drops (p = 0.011) and longer time to completion (p mismatch in some cases. Grip force data recorded from grasper-mounted sensors showed no difference between the different groups. The visual-perceptual mismatch created by the misalignment of the robotic controls relative to the robotic arms has a negative impact on the operator of a robotic surgical system. Introduction of other sensory information and haptic feedback systems can help in potentially reducing this effect.

  10. Fuzzy Backstepping Sliding Mode Control for Mismatched Uncertain System

    Directory of Open Access Journals (Sweden)

    H. Q. Hou

    2014-06-01

    Full Text Available Sliding mode controllers have succeeded in many control problems that the conventional control theories have difficulties to deal with; however it is practically impossible to achieve high-speed switching control. Therefore, in this paper an adaptive fuzzy backstepping sliding mode control scheme is derived for mismatched uncertain systems. Firstly fuzzy sliding mode controller is designed using backstepping method based on the Lyapunov function approach, which is capable of handling mismatched problem. Then fuzzy sliding mode controller is designed using T-S fuzzy model method, it can improve the performance of the control systems and their robustness. Finally this method of control is applied to nonlinear system as a case study; simulation results are also provided the performance of the proposed controller.

  11. Memory detection 2.0: the first web-based memory detection test.

    Science.gov (United States)

    Kleinberg, Bennett; Verschuere, Bruno

    2015-01-01

    There is accumulating evidence that reaction times (RTs) can be used to detect recognition of critical (e.g., crime) information. A limitation of this research base is its reliance upon small samples (average n = 24), and indications of publication bias. To advance RT-based memory detection, we report upon the development of the first web-based memory detection test. Participants in this research (Study1: n = 255; Study2: n = 262) tried to hide 2 high salient (birthday, country of origin) and 2 low salient (favourite colour, favourite animal) autobiographical details. RTs allowed to detect concealed autobiographical information, and this, as predicted, more successfully so than error rates, and for high salient than for low salient items. While much remains to be learned, memory detection 2.0 seems to offer an interesting new platform to efficiently and validly conduct RT-based memory detection research.

  12. Memory detection 2.0: the first web-based memory detection test.

    Directory of Open Access Journals (Sweden)

    Bennett Kleinberg

    Full Text Available There is accumulating evidence that reaction times (RTs can be used to detect recognition of critical (e.g., crime information. A limitation of this research base is its reliance upon small samples (average n = 24, and indications of publication bias. To advance RT-based memory detection, we report upon the development of the first web-based memory detection test. Participants in this research (Study1: n = 255; Study2: n = 262 tried to hide 2 high salient (birthday, country of origin and 2 low salient (favourite colour, favourite animal autobiographical details. RTs allowed to detect concealed autobiographical information, and this, as predicted, more successfully so than error rates, and for high salient than for low salient items. While much remains to be learned, memory detection 2.0 seems to offer an interesting new platform to efficiently and validly conduct RT-based memory detection research.

  13. MutL traps MutS at a DNA mismatch.

    Science.gov (United States)

    Qiu, Ruoyi; Sakato, Miho; Sacho, Elizabeth J; Wilkins, Hunter; Zhang, Xingdong; Modrich, Paul; Hingorani, Manju M; Erie, Dorothy A; Weninger, Keith R

    2015-09-01

    DNA mismatch repair (MMR) identifies and corrects errors made during replication. In all organisms except those expressing MutH, interactions between a DNA mismatch, MutS, MutL, and the replication processivity factor (β-clamp or PCNA) activate the latent MutL endonuclease to nick the error-containing daughter strand. This nick provides an entry point for downstream repair proteins. Despite the well-established significance of strand-specific nicking in MMR, the mechanism(s) by which MutS and MutL assemble on mismatch DNA to allow the subsequent activation of MutL's endonuclease activity by β-clamp/PCNA remains elusive. In both prokaryotes and eukaryotes, MutS homologs undergo conformational changes to a mobile clamp state that can move away from the mismatch. However, the function of this MutS mobile clamp is unknown. Furthermore, whether the interaction with MutL leads to a mobile MutS-MutL complex or a mismatch-localized complex is hotly debated. We used single molecule FRET to determine that Thermus aquaticus MutL traps MutS at a DNA mismatch after recognition but before its conversion to a sliding clamp. Rather than a clamp, a conformationally dynamic protein assembly typically containing more MutL than MutS is formed at the mismatch. This complex provides a local marker where interaction with β-clamp/PCNA could distinguish parent/daughter strand identity. Our finding that MutL fundamentally changes MutS actions following mismatch detection reframes current thinking on MMR signaling processes critical for genomic stability.

  14. MutL traps MutS at a DNA mismatch

    Science.gov (United States)

    Qiu, Ruoyi; Sakato, Miho; Sacho, Elizabeth J.; Wilkins, Hunter; Zhang, Xingdong; Modrich, Paul; Hingorani, Manju M.; Erie, Dorothy A.; Weninger, Keith R.

    2015-01-01

    DNA mismatch repair (MMR) identifies and corrects errors made during replication. In all organisms except those expressing MutH, interactions between a DNA mismatch, MutS, MutL, and the replication processivity factor (β-clamp or PCNA) activate the latent MutL endonuclease to nick the error-containing daughter strand. This nick provides an entry point for downstream repair proteins. Despite the well-established significance of strand-specific nicking in MMR, the mechanism(s) by which MutS and MutL assemble on mismatch DNA to allow the subsequent activation of MutL’s endonuclease activity by β-clamp/PCNA remains elusive. In both prokaryotes and eukaryotes, MutS homologs undergo conformational changes to a mobile clamp state that can move away from the mismatch. However, the function of this MutS mobile clamp is unknown. Furthermore, whether the interaction with MutL leads to a mobile MutS–MutL complex or a mismatch-localized complex is hotly debated. We used single molecule FRET to determine that Thermus aquaticus MutL traps MutS at a DNA mismatch after recognition but before its conversion to a sliding clamp. Rather than a clamp, a conformationally dynamic protein assembly typically containing more MutL than MutS is formed at the mismatch. This complex provides a local marker where interaction with β-clamp/PCNA could distinguish parent/daughter strand identity. Our finding that MutL fundamentally changes MutS actions following mismatch detection reframes current thinking on MMR signaling processes critical for genomic stability. PMID:26283381

  15. Fuzzy Based Advanced Hybrid Intrusion Detection System to Detect Malicious Nodes in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Rupinder Singh

    2017-01-01

    Full Text Available In this paper, an Advanced Hybrid Intrusion Detection System (AHIDS that automatically detects the WSNs attacks is proposed. AHIDS makes use of cluster-based architecture with enhanced LEACH protocol that intends to reduce the level of energy consumption by the sensor nodes. AHIDS uses anomaly detection and misuse detection based on fuzzy rule sets along with the Multilayer Perceptron Neural Network. The Feed Forward Neural Network along with the Backpropagation Neural Network are utilized to integrate the detection results and indicate the different types of attackers (i.e., Sybil attack, wormhole attack, and hello flood attack. For detection of Sybil attack, Advanced Sybil Attack Detection Algorithm is developed while the detection of wormhole attack is done by Wormhole Resistant Hybrid Technique. The detection of hello flood attack is done by using signal strength and distance. An experimental analysis is carried out in a set of nodes; 13.33% of the nodes are determined as misbehaving nodes, which classified attackers along with a detection rate of the true positive rate and false positive rate. Sybil attack is detected at a rate of 99,40%; hello flood attack has a detection rate of 98, 20%; and wormhole attack has a detection rate of 99, 20%.

  16. Anomaly-based Network Intrusion Detection Methods

    Directory of Open Access Journals (Sweden)

    Pavel Nevlud

    2013-01-01

    Full Text Available The article deals with detection of network anomalies. Network anomalies include everything that is quite different from the normal operation. For detection of anomalies were used machine learning systems. Machine learning can be considered as a support or a limited type of artificial intelligence. A machine learning system usually starts with some knowledge and a corresponding knowledge organization so that it can interpret, analyse, and test the knowledge acquired. There are several machine learning techniques available. We tested Decision tree learning and Bayesian networks. The open source data-mining framework WEKA was the tool we used for testing the classify, cluster, association algorithms and for visualization of our results. The WEKA is a collection of machine learning algorithms for data mining tasks.

  17. Cable-Based Water Leak Detection Technology

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    Water leaks can be considered as a serious problem from many sources such as water supply and return chains, air conditioning units, cold-water chillers, clogged drains, damaged skylights or windows, or even construction errors. The new water leak detection technologies can provide significant advantages in cost, reliability, and easy adoption have continued since the traditional technology mainly focusing on a spot detector revealed several limitations.

  18. Carbon-Based Electrodes for Parabens Detection

    OpenAIRE

    Aniela Pop; Ianina Birsan; Corina Orha; Rodica Pode; Florica Manea

    2016-01-01

    Carbon nanofiber-epoxy composite electrode has been investigated through voltammetric and amperometric techniques in order to detect parabens from aqueous solutions. The occurrence into environment as emerging pollutants of these preservative compounds has been extensively studied in the last decades, and consequently, a rapid and reliable method for their quantitative quantification is required. In this study, methylparaben (MP) and propylparaben (PP) were chosen as representatives for parab...

  19. Parkinson's disease detection based on dysphonia measurements

    Science.gov (United States)

    Lahmiri, Salim

    2017-04-01

    Assessing dysphonic symptoms is a noninvasive and effective approach to detect Parkinson's disease (PD) in patients. The main purpose of this study is to investigate the effect of different dysphonia measurements on PD detection by support vector machine (SVM). Seven categories of dysphonia measurements are considered. Experimental results from ten-fold cross-validation technique demonstrate that vocal fundamental frequency statistics yield the highest accuracy of 88 % ± 0.04. When all dysphonia measurements are employed, the SVM classifier achieves 94 % ± 0.03 accuracy. A refinement of the original patterns space by removing dysphonia measurements with similar variation across healthy and PD subjects allows achieving 97.03 % ± 0.03 accuracy. The latter performance is larger than what is reported in the literature on the same dataset with ten-fold cross-validation technique. Finally, it was found that measures of ratio of noise to tonal components in the voice are the most suitable dysphonic symptoms to detect PD subjects as they achieve 99.64 % ± 0.01 specificity. This finding is highly promising for understanding PD symptoms.

  20. Daytime Water Detection Based on Color Variation

    Science.gov (United States)

    Rankin, Arturo L.; Matthies, Larry H.

    2010-01-01

    Robust water detection is a critical perception requirement for unmanned ground vehicle (UGV) autonomous navigation. This is particularly true in wide open areas where water can collect in naturally occurring terrain depressions during periods of heavy precipitation and form large water bodies (such as ponds). At far range, reflections of the sky provide a strong cue for water. But at close range, the color coming out of a water body dominates sky reflections and the water cue from sky reflections is of marginal use. We model this behavior by using water body intensity data from multiple frames of RGB imagery to estimate the total reflection coefficient contribution from surface reflections and the combination of all other factors. Then we describe an algorithm that uses one of the color cameras in a forward- looking, UGV-mounted stereo-vision perception system to detect water bodies in wide open areas. This detector exploits the knowledge that the change in saturation-to-brightness ratio across a water body from the leading to trailing edge is uniform and distinct from other terrain types. In test sequences approaching a pond under clear, overcast, and cloudy sky conditions, the true positive and false negative water detection rates were (95.76%, 96.71%, 98.77%) and (0.45%, 0.60%, 0.62%), respectively. This software has been integrated on an experimental unmanned vehicle and field tested at Ft. Indiantown Gap, PA.

  1. Memory detection 2.0: The first web-based memory detection test

    NARCIS (Netherlands)

    Kleinberg, B.; Verschuere, B.

    2015-01-01

    There is accumulating evidence that reaction times (RTs) can be used to detect recognition of critical (e.g., crime) information. A limitation of this research base is its reliance upon small samples (average n = 24), and indications of publication bias. To advance RT-based memory detection, we

  2. JOB MISMATCH – EFFECTS ON WORK PRODUCTIVITY

    Directory of Open Access Journals (Sweden)

    Magdalena Velciu

    2017-12-01

    Full Text Available Job matching and finding the best person to the right job inside the right company has become one of the most important and actual challenges of productivity. Not only full employment but the match between the employee and the job, in terms of educational level or field of activity, qualifications and skills of workforce; all have been the new gain of work productivity. Present article synthesizes the theoretical and empirical findings on effects of job mismatch by selecting the main findings about influence of job mismatches on work productivity including both employees and companies sides. on short term overeducation and overqualification could have a positive effect on productivity for one company, but on long term, mismatched worker would be affected by decreasing job satisfaction and lower wages. Also, at macroeconomic level, from a perspective of economy as a whole, job mismatches mean a loss of resources and human capital and could have negative effects on overall productivity. The opposite effects stay at the crossing between the employees, companies, policies and future development. In fact the effects of skill mismatch and productivity is a lost of work potential through inefficient resource (reallocation.

  3. An Immunity-Based Anomaly Detection System with Sensor Agents

    Directory of Open Access Journals (Sweden)

    Yoshiteru Ishida

    2009-11-01

    Full Text Available This paper proposes an immunity-based anomaly detection system with sensor agents based on the specificity and diversity of the immune system. Each agent is specialized to react to the behavior of a specific user. Multiple diverse agents decide whether the behavior is normal or abnormal. Conventional systems have used only a single sensor to detect anomalies, while the immunity-based system makes use of multiple sensors, which leads to improvements in detection accuracy. In addition, we propose an evaluation framework for the anomaly detection system, which is capable of evaluating the differences in detection accuracy between internal and external anomalies. This paper focuses on anomaly detection in user’s command sequences on UNIX-like systems. In experiments, the immunity-based system outperformed some of the best conventional systems.

  4. An immunity-based anomaly detection system with sensor agents.

    Science.gov (United States)

    Okamoto, Takeshi; Ishida, Yoshiteru

    2009-01-01

    This paper proposes an immunity-based anomaly detection system with sensor agents based on the specificity and diversity of the immune system. Each agent is specialized to react to the behavior of a specific user. Multiple diverse agents decide whether the behavior is normal or abnormal. Conventional systems have used only a single sensor to detect anomalies, while the immunity-based system makes use of multiple sensors, which leads to improvements in detection accuracy. In addition, we propose an evaluation framework for the anomaly detection system, which is capable of evaluating the differences in detection accuracy between internal and external anomalies. This paper focuses on anomaly detection in user's command sequences on UNIX-like systems. In experiments, the immunity-based system outperformed some of the best conventional systems.

  5. Automatic hearing loss detection system based on auditory brainstem response

    International Nuclear Information System (INIS)

    Aldonate, J; Mercuri, C; Reta, J; Biurrun, J; Bonell, C; Gentiletti, G; Escobar, S; Acevedo, R

    2007-01-01

    Hearing loss is one of the pathologies with the highest prevalence in newborns. If it is not detected in time, it can affect the nervous system and cause problems in speech, language and cognitive development. The recommended methods for early detection are based on otoacoustic emissions (OAE) and/or auditory brainstem response (ABR). In this work, the design and implementation of an automated system based on ABR to detect hearing loss in newborns is presented. Preliminary evaluation in adults was satisfactory

  6. Effects of electrode array length on frequency-place mismatch and speech perception with cochlear implants.

    Science.gov (United States)

    Venail, Frederic; Mathiolon, Caroline; Menjot de Champfleur, Sophie; Piron, Jean Pierre; Sicard, Marielle; Villemus, Françoise; Vessigaud, Marie Aude; Sterkers-Artieres, Françoise; Mondain, Michel; Uziel, Alain

    2015-01-01

    Frequency-place mismatch often occurs after cochlear implantation, yet its effect on speech perception outcome remains unclear. In this article, we propose a method, based on cochlea imaging, to determine the cochlear place-frequency map. We evaluated the effect of frequency-place mismatch on speech perception outcome in subjects implanted with 3 different lengths of electrode arrays. A deeper insertion was responsible for a larger frequency-place mismatch and a decreased and delayed speech perception improvement by comparison with a shallower insertion, for which a similar but slighter effect was noticed. Our results support the notion that selecting an electrode array length adapted to each individual's cochlear anatomy may reduce frequency-place mismatch and thus improve speech perception outcome. © 2015 S. Karger AG, Basel

  7. DNA based methods used for characterization and detection of food ...

    African Journals Online (AJOL)

    Detection of food borne pathogen is of outmost importance in the food industries and related agencies. For the last few decades conventional methods were used to detect food borne pathogens based on phenotypic characters. At the advent of complementary base pairing and amplification of DNA, the diagnosis of food ...

  8. Poseidon: A 2-tier Anomaly-based Intrusion Detection System

    NARCIS (Netherlands)

    Bolzoni, D.; Zambon, Emmanuele; Etalle, Sandro; Hartel, Pieter H.

    2005-01-01

    We present Poseidon, a new anomaly based intrusion detection system. Poseidon is payload-based, and presents a two-tier architecture: the first stage consists of a Self-Organizing Map, while the second one is a modified PAYL system. Our benchmarks on the 1999 DARPA data set show a higher detection

  9. Flatfield correction errors due to spectral mismatching

    Science.gov (United States)

    Hagen, Nathan

    2014-12-01

    Flat field calibration of broadband imaging systems is widely used, and it has been said that users should try to make the spectrum of the flatfield calibration light source as close as possible to that of the measurement object. However, a quantitative analysis of the error induced by a mismatch of calibration and object spectra has been lacking. In order to develop this quantitative analysis, we provide a theoretical radiometric model for flatfield calibration and show how this spectral mismatching error arises. Simulations covering a variety of measurement scenarios indicate that spectral mismatching can create quantitative errors of up to a factor of 5 in situations that are regularly encountered by researchers performing quantitative work.

  10. Stability and Mismatch Discrimination of Locked Nucleic Acid–DNA Duplexes

    Science.gov (United States)

    2011-01-01

    Locked nucleic acids (LNA; symbols of bases, +A, +C, +G, and +T) are introduced into chemically synthesized oligonucleotides to increase duplex stability and specificity. To understand these effects, we have determined thermodynamic parameters of consecutive LNA nucleotides. We present guidelines for the design of LNA oligonucleotides and introduce free online software that predicts the stability of any LNA duplex oligomer. Thermodynamic analysis shows that the single strand–duplex transition is characterized by a favorable enthalpic change and by an unfavorable loss of entropy. A single LNA modification confines the local conformation of nucleotides, causing a smaller, less unfavorable entropic loss when the single strand is restricted to the rigid duplex structure. Additional LNAs adjacent to the initial modification appear to enhance stacking and H-bonding interactions because they increase the enthalpic contributions to duplex stabilization. New nearest-neighbor parameters correctly forecast the positive and negative effects of LNAs on mismatch discrimination. Specificity is enhanced in a majority of sequences and is dependent on mismatch type and adjacent base pairs; the largest discriminatory boost occurs for the central +C·C mismatch within the +T+C+C sequence and the +A·G mismatch within the +T+A+G sequence. LNAs do not affect specificity in some sequences and even impair it for many +G·T and +C·A mismatches. The level of mismatch discrimination decreases the most for the central +G·T mismatch within the +G+G+C sequence and the +C·A mismatch within the +G+C+G sequence. We hypothesize that these discrimination changes are not unique features of LNAs but originate from the shift of the duplex conformation from B-form to A-form. PMID:21928795

  11. Patient - implant dimension mismatch in total knee arthroplasty: Is it worth worrying? An Indian scenario

    Directory of Open Access Journals (Sweden)

    Jai Thilak

    2016-01-01

    Full Text Available Background: The correct sizing of the components in both anteroposterior and mediolateral (ML dimensions is crucial for the success of a total knee arthroplasty (TKA. The size of the implants selected is based on the intraoperative measurements. The currently used TKA implants available to us are based on morphometric measurements obtained from a Western/Caucasian population. Hence, the risk of component ML mismatch is more common in Asian sub-population, as they are of a smaller built and stature. This study aims to look into the following aspects agnitude of the ML mismatch between the femoral component and the patient′s anatomical dimension, evaluation of gender variations in distal femur dimensions, and gender-wise and implant-wise correlation of ML mismatch. Materials and Methods: Intraoperatively, the distal femoral dimensions were measured using sterile calipers after removing the osteophytes and compared with the ML dimension of the implant used. ML mismatch length thus obtained is correlated with the various parameters. Results: Males showed larger distal femoral dimensions when compared to females. Males had larger ML mismatch. None of the implants used perfectly matched the patient′s anatomical dimensions. Patients with larger mismatch had lower scorings at 2 years postoperative followup. Conclusion: Implant manufacturers need to design more options of femoral implants for a better fit in our subset of patients. The exact magnitude of mismatch which can cause functional implications need to be made out. The mismatch being one of the important factors for the success of the surgery, we should focus more on this aspect.

  12. GLRT Based Anomaly Detection for Sensor Network Monitoring

    KAUST Repository

    Harrou, Fouzi

    2015-12-07

    Proper operation of antenna arrays requires continuously monitoring their performances. When a fault occurs in an antenna array, the radiation pattern changes and can significantly deviate from the desired design performance specifications. In this paper, the problem of fault detection in linear antenna arrays is addressed within a statistical framework. Specifically, a statistical fault detection method based on the generalized likelihood ratio (GLR) principle is utilized for detecting potential faults in linear antenna arrays. The proposed method relies on detecting deviations in the radiation pattern of the monitored array with respect to a reference (fault-free) one. To assess the abilities of the GLR based fault detection method, three case studies involving different types of faults have been performed. The simulation results clearly illustrate the effectiveness of the GLR-based fault detection method in monitoring the performance of linear antenna arrays.

  13. A Vehicle Detection Algorithm Based on Deep Belief Network

    Directory of Open Access Journals (Sweden)

    Hai Wang

    2014-01-01

    Full Text Available Vision based vehicle detection is a critical technology that plays an important role in not only vehicle active safety but also road video surveillance application. Traditional shallow model based vehicle detection algorithm still cannot meet the requirement of accurate vehicle detection in these applications. In this work, a novel deep learning based vehicle detection algorithm with 2D deep belief network (2D-DBN is proposed. In the algorithm, the proposed 2D-DBN architecture uses second-order planes instead of first-order vector as input and uses bilinear projection for retaining discriminative information so as to determine the size of the deep architecture which enhances the success rate of vehicle detection. On-road experimental results demonstrate that the algorithm performs better than state-of-the-art vehicle detection algorithm in testing data sets.

  14. A rapid, ratiometric, enzyme-free, and sensitive single-step miRNA detection using three-way junction based FRET probes

    Science.gov (United States)

    Luo, Qingying; Liu, Lin; Yang, Cai; Yuan, Jing; Feng, Hongtao; Chen, Yan; Zhao, Peng; Yu, Zhiqiang; Jin, Zongwen

    2018-03-01

    MicroRNAs (miRNAs) are single stranded endogenous molecules composed of only 18-24 nucleotides which are critical for gene expression regulating the translation of messenger RNAs. Conventional methods based on enzyme-assisted nucleic acid amplification techniques have many problems, such as easy contamination, high cost, susceptibility to false amplification, and tendency to have sequence mismatches. Here we report a rapid, ratiometric, enzyme-free, sensitive, and highly selective single-step miRNA detection using three-way junction assembled (or self-assembled) FRET probes. The developed strategy can be operated within the linear range from subnanomolar to hundred nanomolar concentrations of miRNAs. In comparison with the traditional approaches, our method showed high sensitivity for the miRNA detection and extreme selectivity for the efficient discrimination of single-base mismatches. The results reveal that the strategy paved a new avenue for the design of novel highly specific probes applicable in diagnostics and potentially in microscopic imaging of miRNAs in real biological environments.

  15. Muon Detection Based on a Hadronic Calorimeter

    CERN Document Server

    Ciodaro, T; Abreu, R; Achenbach, R; Adragna, P; Aharrouche, M; Aielli, G; Al-Shabibi, A; Aleksandrov, I; Alexandrov, E; Aloisio, A; Alviggi, M G; Amorim, A; Amram, N; Andrei, V; Anduaga, X; Angelaszek, D; Anjos, N; Annovi, A; Antonelli, S; Anulli, F; Apolle, R; Aracena, I; Ask, S; Åsman, B; Avolio, G; Baak, M; Backes, M; Backlund, S; Badescu, E; Baines, J; Ballestrero, S; Banerjee, S; Bansil, H S; Barnett, B M; Bartoldus, R; Bartsch, V; Batraneanu, S; Battaglia, A; Bauss, B; Beauchemin, P; Beck, H P; Bee, C; Begel, M; Behera, P K; Bell, P; Bell, W H; Bellagamba, L; Bellomo, M; Ben Ami, S; Bendel, M; Benhammou, Y; Benslama, K; Berge, D; Bernius, C; Berry, T; Bianco, M; Biglietti, M; Blair, R E; Bogaerts, A; Bohm, C; Boisvert, V; Bold, T; Bondioli, M; Borer, C; Boscherini, D; Bosman, M; Bossini, E; Boveia, A; Bracinik, J; Brandt, A G; Brawn, I P; Brelier, B; Brenner, R; Bressler, S; Brock, R; Brooks, W K; Brown, G; Brunet, S; Bruni, A; Bruni, G; Bucci, F; Buda, S; Burckhart-Chromek, D; Buscher, V; Buttinger, W; Calvet, S; Camarri, P; Campanelli, M; Canale, V; Canelli, F; Capasso, L; Caprini, M; Caracinha, D; Caramarcu, C; Cardarelli, R; Carlino, G; Casadei, D; Casado, M P; Cattani, G; Cerri, A; Cerrito, L; Chapleau, B; Childers, J T; Chiodini, G; Christidi, I; Ciapetti, G; Cimino, D; Ciobotaru, M; Coccaro, A; Cogan, J; Collins, N J; Conde Muino, P; Conidi, C; Conventi, F; Corradi, M; Corso-Radu, A; Coura Torres, R; Cranmer, K; Crescioli, F; Crone, G; Crupi, R; Cuenca Almenar, C; Cummings, J T; Curtis, C J; Czyczula, Z; Dam, M; Damazio, D; Dao, V; Darlea, G L; Davis, A O; De Asmundis, R; De Pedis, D; De Santo, A; de Seixas, J M; Degenhardt, J; Della Pietra, M; Della Volpe, D; Demers, S; Demirkoz, B; Di Ciaccio, A; Di Mattia, A; Di Nardo, R; Di Simone, A; Diaz, M A; Dietzsch, T A; Dionisi, C; Dobson, E; Dobson, M; dos Anjos, A; Dotti, A; Dova, M T; Drake, G; Dufour, M-A; Dumitru, I; Eckweiler, S; Ehrenfeld, W; Eifert, T; Eisenhandler, E; Ellis, K V; Ellis, N; Emeliyanov, D; Enoque Ferreira de Lima, D; Ermoline, Y; Ernst, J; Etzion, E; Falciano, S; Farrington, S; Farthouat, P; Faulkner , P J W; Fedorko, W; Fellmann, D; Feng, E; Ferrag, S; Ferrari, R; Ferrer, M L; Fiorini, L; Fischer, G; Flowerdew, M J; Fonseca Martin, T; Francis, D; Fratina, S; French, S T; Front, D; Fukunaga, C; Gadomski, S; Garelli, N; Garitaonandia Elejabarrieta, H; Gaudio, G; Gee, C N P; George, S; Giagu, S; Giannetti, P; Gillman, A R; Giorgi, M; Giunta, M; Giusti, P; Goebel, M; Gonçalo, R; Gonzalez Silva, L; Göringer, C; Gorini, B; Gorini, E; Grabowska-Bold, I; Green, B; Groll, M; Guida, A; Guler, H; Haas, S; Hadavand, H; Hadley, D R; Haller, J; Hamilton, A; Hanke, P; Hansen, J R; Hasegawa, S; Hasegawa, Y; Hauser, R; Hayakawa, T; Hayden, D; Head, S; Heim, S; Hellman, S; Henke, M; Hershenhorn, A; Hidvégi, A; Hillert, S; Hillier, S J; Hirayama, S; Hod, N; Hoffmann, D; Hong, T M; Hryn'ova, T; Huston, J; Iacobucci, G; Igonkina, O; Ikeno, M; Ilchenko, Y; Ishikawa, A; Ishino, M; Iwasaki, H; Izzo, V; Jez, P; Jimenez Otero, S; Johansen, M; Johns, K; Jones, G; Joos, M; Kadlecik, P; Kajomovitz, E; Kanaya, N; Kanega, F; Kanno, T; Kapliy, A; Kaushik, V; Kawagoe, K; Kawamoto, T; Kazarov, A; Kehoe, R; Kessoku, K; Khomich, A; Khoriauli, G; Kieft, G; Kirk, J; Klemetti, M; Klofver, P; Klous, S; Kluge, E-E; Kobayashi, T; Koeneke, K; Koletsou, I; Koll, J D; Kolos, S; Kono, T; Konoplich, R; Konstantinidis, N; Korcyl, K; Kordas, K; Kotov, V; Kowalewski, R V; Krasznahorkay, A; Kraus, J; Kreisel, A; Kubota, T; Kugel, A; Kunkle, J; Kurashige, H; Kuze, M; Kwee, R; Laforge, B; Landon, M; Lane, J; Lankford, A J; Laranjeira Lima, S M; Larner, A; Leahu, L; Lehmann Miotto, G; Lei, X; Lellouch, D; Levinson, L; Li, S; Liberti, B; Lilley, J N; Linnemann, J T; Lipeles, E; Lohse, T; Losada, M; Lowe, A; Luci, C; Luminari, L; Lundberg, J; Lupu, N; Machado Miguéns, J; Mackeprang, R; Maettig, S; Magnoni, L; Maiani, C; Maltrana, D; Mangeard, P-S; Männer, R; Mapelli, L; Marchese, F; Marino, C; Martin, B; Martin, B T; Martin, T; Martyniuk, A; Marzano, F; Masik, J; Mastrandrea, P; Matsushita, T; McCarn, A; Mechnich, J; Medinnis, M; Meier, K; Melachrinos, C; Mendoza Nava, L M; Merola, L; Messina, A; Meyer, C P; Middleton, R P; Mikenberg, G; Mills, C M; Mincer, A; Mineev, M; Misiejuk, A; Moa, T; Moenig, K; Monk, J; Monticelli, F; Mora Herrera, C; Morettini, P; Morris, J D; Müller, F; Munwes, Y; Murillo Garcia, R; Nagano, K; Nagasaka, Y; Navarro, G A; Negri, A; Nelson, S; Nemethy, P; Neubauer, M S; Neusiedl, A; Newman, P; Nisati, A; Nomoto, H; Nozaki, M; Nozicka, M; Nurse, E; Ochando, C; Ochi, A; Oda, S; Oh, A; Ohm, C; Okumura, Y; Olivito, D; Omachi, C; Osculati, B; Oshita, H; Ospanov, R; Owen, M A; Özcan, V E; Ozone, K; Padilla, C; Panes, B; Panikashvili, N; Paramonov, A; Parodi, F; Pasqualucci, E; Pastore, F; Patricelli, S; Pauly, T; Perera, V J O; Perez, E; Petcu, M; Petersen, B A; Petersen, J; Petrolo, E; Phan, A; Piegaia, R; Pilkington, A; Pinder, A; Poddar, S; Polini, A; Pope, B G; Potter, C T; Primavera, M; Prokoshin, F; Ptacek, E; Qian, W; Quinonez, F; Rajagopalan, S; Ramos Dos Santos Neves, R; Reinherz-Aronis, E; Reinsch, A; Renkel, P; Rescigno, M; Rieke, S; Riu, I; Robertson, S H; Robinson, M; Rodriguez, D; Roich, A; Romeo, G; Romero, R; Roos, L; Ruiz Martinez, A; Ryabov, Y; Ryan, P; Saavedra, A; Safai Tehrani, F; Sakamoto, H; Salamanna, G; Salamon, A; Saland, J; Salnikov, A; Salvatore, F; Sankey, D P C; Santamarina, C; Santonico, R; Sarkisyan-Grinbaum, E; Sasaki, O; Savu, D; Scannicchio, D A; Schäfer, U; Scharf, V L; Scheirich, D; Schiavi, C; Schlereth, J; Schmitt, K; Schroder, C; Schroer, N; Schultz-Coulon, H-C; Schwienhorst, R; Sekhniaidze, G; Sfyrla, A; Shamim, M; Sherman, D; Shimojima, M; Shochet, M; Shooltz, D; Sidoti, A; Silbert, O; Silverstein, S; Sinev, N; Siragusa, G; Sivoklokov, S; Sjoen, R; Sjölin, J; Slagle, K; Sloper, J E; Smith, B C; Soffer, A; Soloviev, I; Spagnolo, S; Spiwoks, R; Staley, R J; Stamen, R; Stancu, S; Steinberg, P; Stelzer, J; Stockton, M C; Straessner, A; Strauss, E A; Strom, D; Su, D; Sugaya, Y; Sugimoto, T; Sushkov, S; Sutton, M R; Suzuki, Y; Taffard, A; Taiblum, N; Takahashi, Y; Takeda, H; Takeshita, T; Tamsett, M; Tan, C L A; Tanaka, S; Tapprogge, S; Tarem, S; Tarem, Z; Taylor, C; Teixeira-Dias, P; Thomas, J P; Thompson, P D; Thomson, M A; Tokushuku, K; Tollefson, K; Tomoto, M; Topfel, C; Torrence, E; Touchard, F; Traynor, D; Tremblet, L; Tricoli, A; Tripiana, M; Triplett, N; True, P; Tsiakiris, M; Tsuno, S; Tuggle, J; Ünel, G; Urquijo, P; Urrejola, P; Usai, G; Vachon, B; Vallecorsa, S; Valsan, L; Vandelli, W; Vari, R; Vaz Gil Lopes, L; Veneziano, S; Ventura, A; Venturi, N; Vercesi, V; Vermeulen, J C; Volpi, G; Vorwerk, V; Wagner, P; Wang, M; Warburton, A; Watkins, P M; Watson, A T; Watson, M; Weber, P; Weidberg, A R; Wengler, T; Werner, P; Werth, M; Wessels, M; White, M; Whiteson, D; Wickens, F J; Wiedenmann, W; Wielers, M; Winklmeier, F; Woods, K S; Wu, S-L; Wu, X; Xaplanteris Karampatsos, L; Xella, S; Yakovlev, A; Yamazaki, Y; Yang, U; Yasu, Y; Yuan, L; Zaitsev, A; Zanello, L; Zhang, H; Zhang, J; Zhao, L; Zobernig, H; zur Nedden, M

    2010-01-01

    The ATLAS Tile hadronic calorimeter (TileCal) provides highly-segmented energy measurements of incoming particles. The information from TileCal's last segmentation layer can assist in muon tagging and it is being considered for a near future upgrade of the level-one trigger, mainly for rejecting triggers due to cavern background at the barrel region. A muon receiver for the TileCal muon signals is being designed in order to interface with the ATLAS level-one trigger. This paper addresses the preliminary studies concerning the muon discrimination capability for the muon receiver. Monte Carlo simulations for single muons from the interaction point were used to study the effectiveness of hadronic calorimeter information on muon detection.

  16. Muon Detection Based on a Hadronic Calorimeter

    CERN Document Server

    Ciodaro, Thiago; Abreu, R; Achenbach, R; Adragna, P; Aharrouche, M; Aielli, G; Al-Shabibi, A; Aleksandrov, I; Alexandrov, E; Aloisio, A; Alviggi, M G; Amorim, A; Amram, N; Andrei, V; Anduaga, X; Angelaszek, D; Anjos, N; Annovi, A; Antonelli, S; Anulli, F; Apolle, R; Aracena, I; Ask, S; Åsman, B; Avolio, G; Baak, M; Backes, M; Backlund, S; Badescu, E; Baines, J; Ballestrero, S; Banerjee, S; Bansil, H S; Barnett, B M; Bartoldus, R; Bartsch, V; Batraneanu, S; Battaglia, A; Bauss, B; Beauchemin, P; Beck, H P; Bee, C; Begel, M; Behera, P K; Bell, P; Bell, W H; Bellagamba, L; Bellomo, M; Ben Ami, S; Bendel, M; Benhammou, Y; Benslama, K; Berge, D; Bernius, C; Berry, T; Bianco, M; Biglietti, M; Blair, R E; Bogaerts, A; Bohm, C; Boisvert, V; Bold, T; Bondioli, M; Borer, C; Boscherini, D; Bosman, M; Bossini, E; Boveia, A; Bracinik, J; Brandt, A G; Brawn, I P; Brelier, B; Brenner, R; Bressler, S; Brock, R; Brooks, W K; Brown, G; Brunet, S; Bruni, A; Bruni, G; Bucci, F; Buda, S; Burckhart-Chromek, D; Buscher, V; Buttinger, W; Calvet, S; Camarri, P; Campanelli, M; Canale, V; Canelli, F; Capasso, L; Caprini, M; Caracinha, D; Caramarcu, C; Cardarelli, R; Carlino, G; Casadei, D; Casado, M P; Cattani, G; Cerri, A; Cerrito, L; Chapleau, B; Childers, J T; Chiodini, G; Christidi, I; Ciapetti, G; Cimino, D; Ciobotaru, M; Coccaro, A; Cogan, J; Collins, N J; Conde Muino, P; Conidi, C; Conventi, F; Corradi, M; Corso-Radu, A; Coura Torres, R; Cranmer, K; Crescioli, F; Crone, G; Crupi, R; Cuenca Almenar, C; Cummings, J T; Curtis, C J; Czyczula, Z; Dam, M; Damazio, D; Dao, V; Darlea, G L; Davis, A O; De Asmundis, R; De Pedis, D; De Santo, A; de Seixas, J M; Degenhardt, J; Della Pietra, M; Della Volpe, D; Demers, S; Demirkoz, B; Di Ciaccio, A; Di Mattia, A; Di Nardo, R; Di Simone, A; Diaz, M A; Dietzsch, T A; Dionisi, C; Dobson, E; Dobson, M; dos Anjos, A; Dotti, A; Dova, M T; Drake, G; Dufour, M-A; Dumitru, I; Eckweiler, S; Ehrenfeld, W; Eifert, T; Eisenhandler, E; Ellis, K V; Ellis, N; Emeliyanov, D; Enoque Ferreira de Lima, D; Ermoline, Y; Ernst, J; Etzion, E; Falciano, S; Farrington, S; Farthouat, P; Faulkner, P J W; Fedorko, W; Fellmann, D; Feng, E; Ferrag, S; Ferrari, R; Ferrer, M L; Fiorini, L; Fischer, G; Flowerdew, M J; Fonseca Martin, T; Francis, D; Fratina, S; French, S T; Front, D; Fukunaga, C; Gadomski, S; Garelli, N; Garitaonandia Elejabarrieta, H; Gaudio, G; Gee, C N P; George, S; Giagu, S; Giannetti, P; Gillman, A R; Giorgi, M; Giunta, M; Giusti, P; Goebel, M; Gonçalo, R; Gonzalez Silva, L; Göringer, C; Gorini, B; Gorini, E; Grabowska-Bold, I; Green, B; Groll, M; Guida, A; Guler, H; Haas, S; Hadavand, H; Hadley, D R; Haller, J; Hamilton, A; Hanke, P; Hansen, J R; Hasegawa, S; Hasegawa, Y; Hauser, R; Hayakawa, T; Hayden, D; Head, S; Heim, S; Hellman, S; Henke, M; Hershenhorn, A; Hidvégi, A; Hillert, S; Hillier, S J; Hirayama, S; Hod, N; Hoffmann, D; Hong, T M; Hryn'ova, T; Huston, J; Iacobucci, G; Igonkina, O; Ikeno, M; Ilchenko, Y; Ishikawa, A; Ishino, M; Iwasaki, H; Izzo, V; Jez, P; Jimenez Otero, S; Johansen, M; Johns, K; Jones, G; Joos, M; Kadlecik, P; Kajomovitz, E; Kanaya, N; Kanega, F; Kanno, T; Kapliy, A; Kaushik, V; Kawagoe, K; Kawamoto, T; Kazarov, A; Kehoe, R; Kessoku, K; Khomich, A; Khoriauli, G; Kieft, G; Kirk, J; Klemetti, M; Klofver, P; Klous, S; Kluge, E-E; Kobayashi, T; Koeneke, K; Koletsou, I; Koll, J D; Kolos, S; Kono, T; Konoplich, R; Konstantinidis, N; Korcyl, K; Kordas, K; Kotov, V; Kowalewski, R V; Krasznahorkay, A; Kraus, J; Kreisel, A; Kubota, T; Kugel, A; Kunkle, J; Kurashige, H; Kuze, M; Kwee, R; Laforge, B; Landon, M; Lane, J; Lankford, A J; Laranjeira Lima, S M; Larner, A; Leahu, L; Lehmann Miotto, G; Lei, X; Lellouch, D; Levinson, L; Li, S; Liberti, B; Lilley, J N; Linnemann, J T; Lipeles, E; Lohse, T; Losada, M; Lowe, A; Luci, C; Luminari, L; Lundberg, J; Lupu, N; Machado Miguéns, J; Mackeprang, R; Maettig, S; Magnoni, L; Maiani, C; Maltrana, D; Mangeard, P-S; Männer, R; Mapelli, L; Marchese, F; Marino, C; Martin, B; Martin, B T; Martin, T; Martyniuk, A; Marzano, F; Masik, J; Mastrandrea, P; Matsushita, T; McCarn, A; Mechnich, J; Medinnis, M; Meier, K; Melachrinos, C; Mendoza Nava, L M; Merola, L; Messina, A; Meyer, C P; Middleton, R P; Mikenberg, G; Mills, C M; Mincer, A; Mineev, M; Misiejuk, A; Moa, T; Moenig, K; Monk, J; Monticelli, F; Mora Herrera, C; Morettini, P; Morris, J D; Müller, F; Munwes, Y; Murillo Garcia, R; Nagano, K; Nagasaka, Y; Navarro, G A; Negri, A; Nelson, S; Nemethy, P; Neubauer, M S; Neusiedl, A; Newman, P; Nisati, A; Nomoto, H; Nozaki, M; Nozicka, M; Nurse, E; Ochando, C; Ochi, A; Oda, S; Oh, A; Ohm, C; Okumura, Y; Olivito, D; Omachi, C; Osculati, B; Oshita, H; Ospanov, R; Owen, M A; Özcan, V E; Ozone, K; Padilla, C; Panes, B; Panikashvili, N; Paramonov, A; Parodi, F; Pasqualucci, E; Pastore, F; Patricelli, S; Pauly, T; Perera, V J O; Perez, E; Petcu, M; Petersen, B A; Petersen, J; Petrolo, E; Phan, A; Piegaia, R; Pilkington, A; Pinder, A; Poddar, S; Polini, A; Pope, B G; Potter, C T; Primavera, M; Prokoshin, F; Ptacek, E; Qian, W; Quinonez, F; Rajagopalan, S; Ramos Dos Santos Neves, R; Reinherz-Aronis, E; Reinsch, A; Renkel, P; Rescigno, M; Rieke, S; Riu, I; Robertson, S H; Robinson, M; Rodriguez, D; Roich, A; Romeo, G; Romero, R; Roos, L; Ruiz Martinez, A; Ryabov, Y; Ryan, P; Saavedra, A; Safai Tehrani, F; Sakamoto, H; Salamanna, G; Salamon, A; Saland, J; Salnikov, A; Salvatore, F; Sankey, D P C; Santamarina, C; Santonico, R; Sarkisyan-Grinbaum, E; Sasaki, O; Savu, D; Scannicchio, D A; Schäfer, U; Scharf, V L; Scheirich, D; Schiavi, C; Schlereth, J; Schmitt, K; Schroder, C; Schroer, N; Schultz-Coulon, H-C; Schwienhorst, R; Sekhniaidze, G; Sfyrla, A; Shamim, M; Sherman, D; Shimojima, M; Shochet, M; Shooltz, D; Sidoti, A; Silbert, O; Silverstein, S; Sinev, N; Siragusa, G; Sivoklokov, S; Sjoen, R; Sjölin, J; Slagle, K; Sloper, J E; Smith, B C; Soffer, A; Soloviev, I; Spagnolo, S; Spiwoks, R; Staley, R J; Stamen, R; Stancu, S; Steinberg, P; Stelzer, J; Stockton, M C; Straessner, A; Strauss, E A; Strom, D; Su, D; Sugaya, Y; Sugimoto, T; Sushkov, S; Sutton, M R; Suzuki, Y; Taffard, A; Taiblum, N; Takahashi, Y; Takeda, H; Takeshita, T; Tamsett, M; Tan, C L A; Tanaka, S; Tapprogge, S; Tarem, S; Tarem, Z; Taylor, C; Teixeira-Dias, P; Thomas, J P; Thompson, P D; Thomson, M A; Tokushuku, K; Tollefson, K; Tomoto, M; Topfel, C; Torrence, E; Touchard, F; Traynor, D; Tremblet, L; Tricoli, A; Tripiana, M; Triplett, N; True, P; Tsiakiris, M; Tsuno, S; Tuggle, J; Ünel, G; Urquijo, P; Urrejola, P; Usai, G; Vachon, B; Vallecorsa, S; Valsan, L; Vandelli, W; Vari, R; Vaz Gil Lopes, L; Veneziano, S; Ventura, A; Venturi, N; Vercesi, V; Vermeulen, J C; Volpi, G; Vorwerk, V; Wagner, P; Wang, M; Warburton, A; Watkins, P M; Watson, A T; Watson, M; Weber, P; Weidberg, A R; Wengler, T; Werner, P; Werth, M; Wessels, M; White, M; Whiteson, D; Wickens, F J; Wiedenmann, W; Wielers, M; Winklmeier, F; Woods, K S; Wu, S-L; Wu, X; Xaplanteris Karampatsos, L; Xella, S; Yakovlev, A; Yamazaki, Y; Yang, U; Yasu, Y; Yuan, L; Zaitsev, A; Zanello, L; Zhang, H; Zhang, J; Zhao, L; Zobernig, H; zur Nedden, M

    2010-01-01

    The TileCal hadronic calorimeter provides a muon signal which can be used to assist in muon tagging at the ATLAS level-one trigger. Originally, the muon signal was conceived to be combined with the RPC trigger in order to reduce unforeseen high trigger rates due to cavern background. Nevertheless, the combined trigger cannot significantly deteriorate the muon detection performance at the barrel region. This paper presents preliminary studies concerning the impact in muon identification at the ATLAS level-one trigger, through the use of Monte Carlo simulations with single muons with 40 GeV/c momentum. Further, different trigger scenarios were proposed, together with an approach for matching both TileCal and RPC geometries.

  17. Humidity detection using chitosan film based sensor

    Science.gov (United States)

    Nasution, T. I.; Nainggolan, I.; Dalimunthe, D.; Balyan, M.; Cuana, R.; Khanifah, S.

    2018-02-01

    A humidity sensor made of the natural polymer chitosan has been successfully fabricated in the film form by a solution casting method. Humidity testing was performed by placing a chitosan film sensor in a cooling machine room, model KT-2000 Ahu. The testing results showed that the output voltage values of chitosan film sensor increased with the increase in humidity percentage. For the increase in humidity percentage from 30 to 90% showed that the output voltage of chitosan film sensor increased from 32.19 to 138.75 mV. It was also found that the sensor evidenced good repeatability and stability during the testing. Therefore, chitosan has a great potential to be used as new sensing material for the humidity detection of which was cheaper and environmentally friendly.

  18. Mismatch and noise in modern IC processes

    CERN Document Server

    Marshall, Andrew

    2009-01-01

    Component variability, mismatch, and various noise effects are major contributors to design limitations in most modern IC processes. Mismatch and Noise in Modern IC Processes examines these related effects and how they affect the building block circuits of modern integrated circuits, from the perspective of a circuit designer.Variability usually refers to a large scale variation that can occur on a wafer to wafer and lot to lot basis, and over long distances on a wafer. This phenomenon is well understood and the effects of variability are included in most integrated circuit design with the use

  19. Robust face detection based on components and their topology

    Science.gov (United States)

    Goldmann, Lutz; Mönich, Ullrich; Sikora, Thomas

    2006-01-01

    This paper presents a novel approach for automatic and robust object detection. It utilizes a component-based approach that combines techniques from both statistical and structural pattern recognition domain. While the component detection relies on Haar-like features and an AdaBoost trained classifier cascade, the topology verification is based on graph matching techniques. The system was applied to face detection and the experiments show its outstanding performance in comparison to other face detection approaches. Especially in the presence of partial occlusions, uneven illumination and out-of-plane rotations it yields higher robustness.

  20. Segment-based change detection for polarimetric SAR data

    DEFF Research Database (Denmark)

    Skriver, Henning; Nielsen, Allan Aasbjerg; Conradsen, Knut

    2006-01-01

    single-channel SAR images but multi-channel algorithms have also been described. Different approaches have been used for image segmentation. Edge detection combined with region growing is one approach, where segments are created by growing regions from a previously edge detected and edge thinned image....... This method relies primarily on a robust edge detector, which preferably provides a constant false alarm rate. For single-channel SAR images this is fulfilled by the ratio edge detector, and for polarimetric SAR data, an edge detector based on the above mentioned test statistic fulfils this. Another approach......, wetlands, lakes, and urban areas. Also, other test sites over for instance urban areas have been used to assess the improvement by the segment-based change detection method. In the paper, results from pixel-based change detection, i.e. without segmentation, and from segment-based change detection, where...

  1. Ultrasensitive detection of DNA and RNA based on enzyme-free click chemical ligation chain reaction on dispersed gold nanoparticles.

    Science.gov (United States)

    Kato, Daiki; Oishi, Motoi

    2014-10-28

    An ultrasensitive colorimetric DNA and RNA assay using a combination of enzyme-free click chemical ligation chain reaction (CCLCR) on dispersed gold nanoparticles (GNPs) and a magnetic separation process has been developed. The click chemical ligation between an azide-containing probe DNA-modified GNP and a dibenzocyclooctyne-containing probe biotinyl DNA occurred through hybridization with target DNA (RNA) to form the biotinyl-ligated GNPs (ligated products). Eventually, both the biotinyl-ligated GNPs and target DNA (RNA) were amplified exponentially using thermal cycling. After separation of the biotinyl-ligated GNPs using streptavidin-modified magnetic beads, the change in intensity of the surface plasmon band at 525 nm in the supernatants was observed by UV/vis measurement and was also evident visually. The CCLCR assay provides ultrasensitive detection (50 zM: several copies) of target DNA that is comparable to PCR-based approaches. Note that target RNA could also be detected with similar sensitivity without the need for reverse transcription to the corresponding cDNA. The amplification efficiency of the CCLCR assay was as high as 82% due to the pseudohomogeneous reaction behavior of CCLCR on dispersed GNPs. In addition, the CCLCR assay was able to discriminate differences in single-base mismatches and to specifically detect target DNA and target RNA from the cell lysate.

  2. Research on moving object detection based on frog's eyes

    Science.gov (United States)

    Fu, Hongwei; Li, Dongguang; Zhang, Xinyuan

    2008-12-01

    On the basis of object's information processing mechanism with frog's eyes, this paper discussed a bionic detection technology which suitable for object's information processing based on frog's vision. First, the bionics detection theory by imitating frog vision is established, it is an parallel processing mechanism which including pick-up and pretreatment of object's information, parallel separating of digital image, parallel processing, and information synthesis. The computer vision detection system is described to detect moving objects which has special color, special shape, the experiment indicates that it can scheme out the detecting result in the certain interfered background can be detected. A moving objects detection electro-model by imitating biologic vision based on frog's eyes is established, the video simulative signal is digital firstly in this system, then the digital signal is parallel separated by FPGA. IN the parallel processing, the video information can be caught, processed and displayed in the same time, the information fusion is taken by DSP HPI ports, in order to transmit the data which processed by DSP. This system can watch the bigger visual field and get higher image resolution than ordinary monitor systems. In summary, simulative experiments for edge detection of moving object with canny algorithm based on this system indicate that this system can detect the edge of moving objects in real time, the feasibility of bionic model was fully demonstrated in the engineering system, and it laid a solid foundation for the future study of detection technology by imitating biologic vision.

  3. Aptamer-Based Technologies in Foodborne Pathogen Detection

    Directory of Open Access Journals (Sweden)

    Jun Teng

    2016-09-01

    Full Text Available Aptamers are single stranded DNA or RNA ligands, which can be selected by a method called systematic evolution of ligands by exponential enrichment (SELEX; and they can specifically recognize and bind to their targets. These unique characteristics of aptamers offer great potentials in applications such as pathogen detection and biomolecular screening. Pathogen detection is the first and critical means in detecting and identifying the problems related to public health and food safety; and only the rapid, sensitive and efficient detection technologies can enable the users to make to accurate assessments on the risk of infections (humans and animals or contaminations (foods and other commodities caused by various pathogens. This article reviews the developments in the field of the aptamer-based approaches for pathogen detection, including whole-cell SELEX and Genomic SELEX. Nowadays, a variety of aptamer-based biosensors have been developed for pathogen detection. Thus, in this review, we also cover the development of aptamer-based biosensors including optical biosensors for multiple pathogen detection in multiple-labeling or label-free models such as fluorescence detection and surface plasmon resonance, electrochemical biosensors, and lateral chromatography test strips, and their applications in the pathogen detection and biomolecular screening. While notable progress has been made in the field in the last decade, challenges or drawbacks in their applications such as pathogen detection and biomolecular screening, remain to be overcome.

  4. Aptamer-Based Technologies in Foodborne Pathogen Detection.

    Science.gov (United States)

    Teng, Jun; Yuan, Fang; Ye, Yingwang; Zheng, Lei; Yao, Li; Xue, Feng; Chen, Wei; Li, Baoguang

    2016-01-01

    Aptamers are single stranded DNA or RNA ligands, which can be selected by a method called systematic evolution of ligands by exponential enrichment (SELEX); and they can specifically recognize and bind to their targets. These unique characteristics of aptamers offer great potentials in applications such as pathogen detection and biomolecular screening. Pathogen detection is the critical means in detecting and identifying the problems related to public health and food safety; and only the rapid, sensitive and efficient detection technologies can enable the users to make the accurate assessments on the risks of infections (humans and animals) or contaminations (foods and other commodities) caused by various pathogens. This article reviews the development in the field of the aptamer-based approaches for pathogen detection, including whole-cell SELEX and Genomic SELEX. Nowadays, a variety of aptamer-based biosensors have been developed for pathogen detection. Thus, in this review, we also cover the development in aptamer-based biosensors including optical biosensors for multiple pathogen detection by multiple-labeling or label-free models such as fluorescence detection and surface plasmon resonance, electrochemical biosensors and lateral chromatography test strips, and their applications in pathogen detection and biomolecular screening. While notable progress has been made in the field in the last decade, challenges or drawbacks in their applications such as pathogen detection and biomolecular screening remain to be overcome.

  5. Multiplex Detection and Genotyping of Point Mutations Involved in Charcot-Marie-Tooth Disease Using a Hairpin Microarray-Based Assay

    Directory of Open Access Journals (Sweden)

    Yasser Baaj

    2009-01-01

    Full Text Available We previously developed a highly specific method for detecting SNPs with a microarray-based system using stem-loop probes. In this paper we demonstrate that coupling a multiplexing procedure with our microarray method is possible for the simultaneous detection and genotyping of four point mutations, in three different genes, involved in Charcot-Marie-Tooth disease. DNA from healthy individuals and patients was amplified, labeled with Cy3 by multiplex PCR; and hybridized to microarrays. Spot signal intensities were 18 to 74 times greater for perfect matches than for mismatched target sequences differing by a single nucleotide (discrimination ratio for “homozygous” DNA from healthy individuals. “Heterozygous” mutant DNA samples gave signal intensity ratios close to 1 at the positions of the mutations as expected. Genotyping by this method was therefore reliable. This system now combines the principle of highly specific genotyping based on stem-loop structure probes with the advantages of multiplex analysis.

  6. Accelerator based techniques for contraband detection

    Science.gov (United States)

    Vourvopoulos, George

    1994-05-01

    It has been shown that narcotics, explosives, and other contraband materials, contain various chemical elements such as H, C, N, O, P, S, and Cl in quantities and ratios that differentiate them from each other and from other innocuous substances. Neutrons and γ-rays have the ability to penetrate through various materials at large depths. They are thus able, in a non-intrusive way, to interrogate volumes ranging from suitcases to Sea-Land containers, and have the ability to image the object with an appreciable degree of reliability. Neutron induced reactions such as (n, γ), (n, n') (n, p) or proton induced γ-resonance absorption are some of the reactions currently investigated for the identification of the chemical elements mentioned above. Various DC and pulsed techniques are discussed and their advantages, characteristics, and current progress are shown. Areas where use of these methods is currently under evaluation are detection of hidden explosives, illicit drug interdiction, chemical war agents identification, nuclear waste assay, nuclear weapons destruction and others.

  7. Novel gas-based detection techniques

    International Nuclear Information System (INIS)

    Graaf, Harry van der

    2009-01-01

    This year we celebrate the 100th birthday of gaseous detectors: Hans Geiger operated the first gas-filled counter in Manchester in 1908. The thin wires, essential for obtaining gas amplification, have been replaced by Micro Pattern Gas Detectors (MPGDs): Micromegas (1995) and GEM (1996). In the GridPix detector, each of the grid holes of a MPGD is equipped with its own electronic readout channel in the form of an active pixel in suitable pixel CMOS chips. By means of MEMS technology, the grid has been integrated with the chip, forming a monolithic readout device for gas volumes. By applying a protection layer made of hydrogenated amorphous silicon, the chips can be made spark proof. New protection layers have been made of silicon nitride. The use of gas as detection material for trackers is compared to Si, and the issue of chamber aging is addressed. New developments are set out: the development of Micro Channel Plates, integrated on pixel chips, the development of electron emission foil, and the realization of TimePix-2: a general-purpose pixel chip with time and amplitude measurement, per pixel, of charge signals.

  8. Neutron detection with water Cerenkov based detectors

    International Nuclear Information System (INIS)

    Dazeley, S.; Bernstein, A.; Bowden, N.; Carr, D.; Ouedraogo, S.; Svoboda, R.; Sweany, M.; Tripathi, M.

    2009-01-01

    Legitimate cross border trade involves the transport of an enormous number of cargo containers. Especially following the September 11 attacks, it has become an international priority to verify that these containers are not transporting Special Nuclear Material (SNM) without impeding legitimate trade. Fission events from SNM produce a number of neutrons and MeV-scale gammas correlated in time. The observation of consistent time correlations between neutrons and gammas emitted from a cargo container could, therefore, constitute a robust signature for SNM, since this time coincident signature stands out strongly against the higher rate of uncorrelated gamma-ray backgrounds from the local environment. We are developing a cost effective way to build very large neutron detectors for this purpose. We have recently completed the construction of two new water Cherenkov detectors, a 250 liter prototype and a new 4-ton detector. The 250-liter prototype uses an ultra-pure water detection medium doped with a small amount of gadolinium tri-chloride (0.2%). A 55 μCi 252 Cf neutron source was placed at a distance of 1 meter from the detector behind a 2 inch thick wall of lead. The presence of the source is easily discernible from the background in both the uncorrelated count rate and the correlated one. The 4-ton detector will shortly undergo filling and testing

  9. Lymph node yield after colectomy for cancer: is absence of mismatch repair a factor?

    Science.gov (United States)

    Samdani, Tushar; Schultheis, Molly; Stadler, Zsofia; Shia, Jinru; Fancher, Tiffany; Misholy, Justine; Weiser, Martin R; Nash, Garrett M

    2015-03-01

    Nodal staging is crucial in determining the use of adjuvant chemotherapy for colon cancer. The number of metastatic lymph nodes has been positively correlated with the number of lymph nodes examined. Current guidelines recommend that at minimum 12 to 14 lymph nodes be assessed. In some studies, mismatch repair deficiency has been associated with lymph node yield. The purpose of this work was to determine whether mismatch repair-deficient colorectal tumors are associated with increased lymph node yield. We queried an institutional database to analyze colectomy specimens with immunohistochemistry for mismatch repair genes in patients treated for colorectal cancer between 1999 and 2012. Before 2006, immunohistochemistry was performed at the request of an oncologist or surgeon. After 2006, it was routinely performed for patients mismatch repair deficiency. On univariate analysis, mismatch repair deficiency was associated with lower lymph node yield, older patient age, right-sided tumors, and poor differentiation. The linear regression model identified 5 variables with independent relationships to lymph node yield, including patient age, specimen length, lymph node ratio, perineural invasion, and tumor size. A positive correlation was observed with tumor size, specimen length, and perineural invasion. Tumor location had a more complex, nonlinear, quadratic relationship with lymph node yield; proximal tumors were associated with a higher yield than more distal lesions. Mismatch repair deficiency was not independently associated with lymph node yield. Mismatch repair immunohistochemistry based on patient age, family history, and pathologic features may reduce the generalizability of these results. Our sample size was too small to identify variables with small measures of effect. The retrospective nature of the study did not permit a true assessment of the extent of mesenteric resection. Patient age, length of bowel resected, lymph node ratio, perineural invasion, tumor

  10. Arc Security System Based on Harmonics Detection for the TS ICRH Transmitter

    International Nuclear Information System (INIS)

    Berger-by, G.; Beaumont, B.; Lombard, G.; Millon, L.; Mollard, P.; Volpe, D.

    2006-01-01

    Since 1999 and with the help of I.P.P. (Institut fuer Plasmaphysik) Garching, we have tested in the Tore Supra (T.S.) ICRH transmitter, arcs security systems based on harmonics detection in a frequency band lower than the generator frequency. These systems have been designed for ASDEX in order to discriminate between the arcs and the ELMS mismatches during H-mode plasmas; they have been supplied to T.S. by a loan contract by I.P.P. The first tests done in T.S. were very successful and have permitted in 2000 to build a prototype matching T.S. technical requirements. These systems have some advantages in comparison with traditional securities which are based on use of a level on the V r /V f (Reflected to Forward voltage ratio) calculation . They do not use calculation, calibration with frequency or level. They can use RF signals from directional couplers or probes, so they are fully independent of the measurement systems. The detection bandwidth (4 MHz-35 MHz on TS) is independent of the antennae working frequencies. The detection principle is therefore insensitive to the crosstalk between the antennae and to the antennae coupling variations. The RF arc security box is installed in the generator hall which can be located far from the torus hall and the antennae (about 50 m on T.S.) a feature which is very relevant for the ITER transmitters. In 2001 we have built 3 systems based on our prototype in order to improve the protection of the 3 ICRH generators and antennae. These systems use industrial pass-band filters and a very sensitive linear detection (- 60 dBm) in order to facilitate the adjustment. Optical fibbers are used to transfer, with a very high immunity, the trip information to the generator electronic pilot. To guarantee safe operation, a checking test of the entire security chain is performed with a 10 MHz RF oscillator before each plasma start. The RF principle used on T.S. ICRH transmitter and its electronic interactions with the VME command control of

  11. GNSS Spoofing Detection Based on Signal Power Measurements: Statistical Analysis

    Directory of Open Access Journals (Sweden)

    V. Dehghanian

    2012-01-01

    Full Text Available A threat to GNSS receivers is posed by a spoofing transmitter that emulates authentic signals but with randomized code phase and Doppler values over a small range. Such spoofing signals can result in large navigational solution errors that are passed onto the unsuspecting user with potentially dire consequences. An effective spoofing detection technique is developed in this paper, based on signal power measurements and that can be readily applied to present consumer grade GNSS receivers with minimal firmware changes. An extensive statistical analysis is carried out based on formulating a multihypothesis detection problem. Expressions are developed to devise a set of thresholds required for signal detection and identification. The detection processing methods developed are further manipulated to exploit incidental antenna motion arising from user interaction with a GNSS handheld receiver to further enhance the detection performance of the proposed algorithm. The statistical analysis supports the effectiveness of the proposed spoofing detection technique under various multipath conditions.

  12. Research about Memory Detection Based on the Embedded Platform

    Science.gov (United States)

    Sun, Hao; Chu, Jian

    As is known to us all, the resources of memory detection of the embedded systems are very limited. Taking the Linux-based embedded arm as platform, this article puts forward two efficient memory detection technologies according to the characteristics of the embedded software. Especially for the programs which need specific libraries, the article puts forwards portable memory detection methods to help program designers to reduce human errors,improve programming quality and therefore make better use of the valuable embedded memory resource.

  13. Developing nucleic acid-based electrical detection systems

    Directory of Open Access Journals (Sweden)

    Gabig-Ciminska Magdalena

    2006-03-01

    Full Text Available Abstract Development of nucleic acid-based detection systems is the main focus of many research groups and high technology companies. The enormous work done in this field is particularly due to the broad versatility and variety of these sensing devices. From optical to electrical systems, from label-dependent to label-free approaches, from single to multi-analyte and array formats, this wide range of possibilities makes the research field very diversified and competitive. New challenges and requirements for an ideal detector suitable for nucleic acid analysis include high sensitivity and high specificity protocol that can be completed in a relatively short time offering at the same time low detection limit. Moreover, systems that can be miniaturized and automated present a significant advantage over conventional technology, especially if detection is needed in the field. Electrical system technology for nucleic acid-based detection is an enabling mode for making miniaturized to micro- and nanometer scale bio-monitoring devices via the fusion of modern micro- and nanofabrication technology and molecular biotechnology. The electrical biosensors that rely on the conversion of the Watson-Crick base-pair recognition event into a useful electrical signal are advancing rapidly, and recently are receiving much attention as a valuable tool for microbial pathogen detection. Pathogens may pose a serious threat to humans, animal and plants, thus their detection and analysis is a significant element of public health. Although different conventional methods for detection of pathogenic microorganisms and their toxins exist and are currently being applied, improvements of molecular-based detection methodologies have changed these traditional detection techniques and introduced a new era of rapid, miniaturized and automated electrical chip detection technologies into pathogen identification sector. In this review some developments and current directions in

  14. Educational Mismatch and the Careers of Scientists

    Science.gov (United States)

    Bender, Keith A.; Heywood, John S.

    2011-01-01

    Previous research confirms that many employees work in jobs not well matched to their skills and education, resulting in lower pay and job satisfaction. While this literature typically uses cross-sectional data, we examine the evolution of mismatch and its consequences over a career, by using a panel data set of scientists in the USA. The results…

  15. Preventing mismatch answers in standardized survey interviews

    NARCIS (Netherlands)

    Ongena, Yfke P.; Dijkstra, Wil

    Interaction analysis of question–answer sequences from a telephone survey shows that so-called mismatch answers, i.e. answers that do not correspond to the required answering format, are the most frequently occurring problematic verbal behavior. They also are likely to trigger suggestive interviewer

  16. Mismatch Repair during Homologous and Homeologous Recombination

    Science.gov (United States)

    Spies, Maria; Fishel, Richard

    2015-01-01

    Homologous recombination (HR) and mismatch repair (MMR) are inextricably linked. HR pairs homologous chromosomes before meiosis I and is ultimately responsible for generating genetic diversity during sexual reproduction. HR is initiated in meiosis by numerous programmed DNA double-strand breaks (DSBs; several hundred in mammals). A characteristic feature of HR is the exchange of DNA strands, which results in the formation of heteroduplex DNA. Mismatched nucleotides arise in heteroduplex DNA because the participating parental chromosomes contain nonidentical sequences. These mismatched nucleotides may be processed by MMR, resulting in nonreciprocal exchange of genetic information (gene conversion). MMR and HR also play prominent roles in mitotic cells during genome duplication; MMR rectifies polymerase misincorporation errors, whereas HR contributes to replication fork maintenance, as well as the repair of spontaneous DSBs and genotoxic lesions that affect both DNA strands. MMR suppresses HR when the heteroduplex DNA contains excessive mismatched nucleotides, termed homeologous recombination. The regulation of homeologous recombination by MMR ensures the accuracy of DSB repair and significantly contributes to species barriers during sexual reproduction. This review discusses the history, genetics, biochemistry, biophysics, and the current state of studies on the role of MMR in homologous and homeologous recombination from bacteria to humans. PMID:25731766

  17. Distributivity and Agreement mismatches in Serbian

    NARCIS (Netherlands)

    Bosnic, Ana

    2016-01-01

    This paper presents a truth value judgment study done on two types of numerals in the Serbian numerical system and corresponding verbal agreement mismatch that is characteristic for the numerals in question. Recent work on agreement and distributivity suggests that singular verbal marking promotes

  18. HLA mismatches and PRA in kidney retransplants.

    Science.gov (United States)

    Mizutani, Kazuo

    2007-01-01

    1. For kidney transplants, overall graft survival with 1st transplants was better than with multiple transplants. 2. One-year graft survival rates have become similar with 1st and 2nd transplants, but some differences persisted for 5-year survival. 3. HLA mismatches have decreased with both 1st and 2nd DDTs, but with 1st and 2nd LDTs HLA mismatches remained at almost the same level. 4. PRA levels increased with the number of transplants. 5. The percent of 1st transplant patients with 0% PRA has increased year by year. However, with 2nd transplants the percent with higher PRA levels also increased year by year. 6. The trend in number of HLA mismatches was similar with both 1st and 2nd DDTs and LDTs even when higher HLA mismatch levels increased over the years. 7. The graft survival of all PRA levels improved. The differences in 1-year graft survival between each PRA group became smaller, and pretransplant PRA diminished with 1-year graft survival. However, pretransplant PRA still affected 5-year graft survival.

  19. Scintillation particle detection based on microfluidics

    CERN Document Server

    Mapelli, A; Renaud, P; Gorini, B; Trivino, N Vico; Jiguet, S; Vandelli, W; Haguenauer, M

    2010-01-01

    A novel type of particle detector based on scintillation, with precise spatial resolution and high radiation hardness, is being studied. It consists of a single microfluidic channel filled with a liquid scintillator and is designed to define an array of scintillating waveguides each independently coupled to a photodetector. Prototype detectors built using an SU-8 epoxy resin have been tested with electrons from a radioactive source. The experimental results show a light yield compatible with the theoretical expectations and confirm the validity of the approach. (C) 2010 Elsevier B.V. All rights reserved.

  20. Multifeature Fusion Vehicle Detection Algorithm Based on Choquet Integral

    Directory of Open Access Journals (Sweden)

    Wenhui Li

    2014-01-01

    Full Text Available Vision-based multivehicle detection plays an important role in Forward Collision Warning Systems (FCWS and Blind Spot Detection Systems (BSDS. The performance of these systems depends on the real-time capability, accuracy, and robustness of vehicle detection methods. To improve the accuracy of vehicle detection algorithm, we propose a multifeature fusion vehicle detection algorithm based on Choquet integral. This algorithm divides the vehicle detection problem into two phases: feature similarity measure and multifeature fusion. In the feature similarity measure phase, we first propose a taillight-based vehicle detection method, and then vehicle taillight feature similarity measure is defined. Second, combining with the definition of Choquet integral, the vehicle symmetry similarity measure and the HOG + AdaBoost feature similarity measure are defined. Finally, these three features are fused together by Choquet integral. Being evaluated on public test collections and our own test images, the experimental results show that our method has achieved effective and robust multivehicle detection in complicated environments. Our method can not only improve the detection rate but also reduce the false alarm rate, which meets the engineering requirements of Advanced Driving Assistance Systems (ADAS.

  1. Video-Based Affect Detection in Noninteractive Learning Environments

    Science.gov (United States)

    Chen, Yuxuan; Bosch, Nigel; D'Mello, Sidney

    2015-01-01

    The current paper explores possible solutions to the problem of detecting affective states from facial expressions during text/diagram comprehension, a context devoid of interactive events that can be used to infer affect. These data present an interesting challenge for face-based affect detection because likely locations of affective facial…

  2. Revisiting Anomaly-based Network Intrusion Detection Systems

    NARCIS (Netherlands)

    Bolzoni, D.

    2009-01-01

    Intrusion detection systems (IDSs) are well-known and widely-deployed security tools to detect cyber-attacks and malicious activities in computer systems and networks. A signature-based IDS works similar to anti-virus software. It employs a signature database of known attacks, and a successful match

  3. Model Based Fault Detection in a Centrifugal Pump Application

    DEFF Research Database (Denmark)

    Kallesøe, Carsten; Cocquempot, Vincent; Izadi-Zamanabadi, Roozbeh

    2006-01-01

    A model based approach for fault detection in a centrifugal pump, driven by an induction motor, is proposed in this paper. The fault detection algorithm is derived using a combination of structural analysis, observer design and Analytical Redundancy Relation (ARR) design. Structural considerations...

  4. The field effect transistor DNA biosensor based on ITO nanowires in label-free hepatitis B virus detecting compatible with CMOS technology.

    Science.gov (United States)

    Shariati, Mohsen

    2018-05-15

    In this paper the field-effect transistor DNA biosensor for detecting hepatitis B virus (HBV) based on indium tin oxide nanowires (ITO NWs) in label free approach has been fabricated. Because of ITO nanowires intensive conductance and functional modified surface, the probe immobilization and target hybridization were increased strongly. The high resolution transmission electron microscopy (HRTEM) measurement showed that ITO nanowires were crystalline and less than 50nm in diameter. The single-stranded hepatitis B virus DNA (SS-DNA) was immobilized as probe on the Au-modified nanowires. The DNA targets were measured in a linear concentration range from 1fM to 10µM. The detection limit of the DNA biosensor was about 1fM. The time of the hybridization process for defined single strand was 90min. The switching ratio of the biosensor between "on" and "off" state was ~ 1.1 × 10 5 . For sensing the specificity of the biosensor, non-complementary, mismatch and complementary DNA oligonucleotide sequences were clearly discriminated. The HBV biosensor confirmed the highly satisfied specificity for differentiating complementary sequences from non-complementary and the mismatch oligonucleotides. The response time of the DNA sensor was 37s with a high reproducibility. The stability and repeatability of the DNA biosensor showed that the peak current of the biosensor retained 98% and 96% of its initial response for measurements after three and five weeks, respectively. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Channel normalization technique for speech recognition in mismatched conditions

    CSIR Research Space (South Africa)

    Kleynhans, N

    2008-11-01

    Full Text Available The performance of trainable speech-processing systems deteriorates significantly when there is a mismatch between the training and testing data. The data mismatch becomes a dominant factor when collecting speech data for resource scarce languages...

  6. Vibration Based Sun Gear Damage Detection

    Science.gov (United States)

    Hood, Adrian; LaBerge, Kelsen; Lewicki, David; Pines, Darryll

    2013-01-01

    Seeded fault experiments were conducted on the planetary stage of an OH-58C helicopter transmission. Two vibration based methods are discussed that isolate the dynamics of the sun gear from that of the planet gears, bearings, input spiral bevel stage, and other components in and around the gearbox. Three damaged sun gears: two spalled and one cracked, serve as the focus of this current work. A non-sequential vibration separation algorithm was developed and the resulting signals analyzed. The second method uses only the time synchronously averaged data but takes advantage of the signal/source mapping required for vibration separation. Both algorithms were successful in identifying the spall damage. Sun gear damage was confirmed by the presence of sun mesh groups. The sun tooth crack condition was inconclusive.

  7. Ensemble of classifiers based network intrusion detection system performance bound

    CSIR Research Space (South Africa)

    Mkuzangwe, Nenekazi NP

    2017-11-01

    Full Text Available This paper provides a performance bound of a network intrusion detection system (NIDS) that uses an ensemble of classifiers. Currently researchers rely on implementing the ensemble of classifiers based NIDS before they can determine the performance...

  8. Adaptive, Model-Based Monitoring and Threat Detection

    National Research Council Canada - National Science Library

    Valdes, Alfonso

    2002-01-01

    .... We describe a network intrusion detection system (IDS) using Bayes inference, wherein the knowledge base is encoded not as rules but as conditional probability relations between observables and hypotheses of normal and malicious usage...

  9. Algorithms for Speeding up Distance-Based Outlier Detection

    Data.gov (United States)

    National Aeronautics and Space Administration — The problem of distance-based outlier detection is difficult to solve efficiently in very large datasets because of potential quadratic time complexity. We address...

  10. Functional MRI-based lie detection: scientific and societal challenges.

    Science.gov (United States)

    Farah, Martha J; Hutchinson, J Benjamin; Phelps, Elizabeth A; Wagner, Anthony D

    2014-02-01

    Functional MRI (fMRI)-based lie detection has been marketed as a tool for enhancing personnel selection, strengthening national security and protecting personal reputations, and at least three US courts have been asked to admit the results of lie detection scans as evidence during trials. How well does fMRI-based lie detection perform, and how should the courts, and society more generally, respond? Here, we address various questions — some of which are based on a meta-analysis of published studies — concerning the scientific state of the art in fMRI-based lie detection and its legal status, and discuss broader ethical and societal implications. We close with three general policy recommendations.

  11. Knowledge-Base Application to Ground Moving Target Detection

    National Research Council Canada - National Science Library

    Adve, R

    2001-01-01

    This report summarizes a multi-year in-house effort to apply knowledge-base control techniques and advanced Space-Time Adaptive Processing algorithms to improve detection performance and false alarm...

  12. Vehicle Detection Based on Probability Hypothesis Density Filter

    Directory of Open Access Journals (Sweden)

    Feihu Zhang

    2016-04-01

    Full Text Available In the past decade, the developments of vehicle detection have been significantly improved. By utilizing cameras, vehicles can be detected in the Regions of Interest (ROI in complex environments. However, vision techniques often suffer from false positives and limited field of view. In this paper, a LiDAR based vehicle detection approach is proposed by using the Probability Hypothesis Density (PHD filter. The proposed approach consists of two phases: the hypothesis generation phase to detect potential objects and the hypothesis verification phase to classify objects. The performance of the proposed approach is evaluated in complex scenarios, compared with the state-of-the-art.

  13. USING MORPHLET-BASED IMAGE REPRESENTATION FOR OBJECT DETECTION

    Directory of Open Access Journals (Sweden)

    V. S. Gorbatsevich

    2016-06-01

    Full Text Available In this paper, we propose an original method for objects detection based on a special tree-structured image representation – the trees of morphlets. The method provides robust detection of various types of objects in an image without employing a machine learning procedure. Along with a bounding box creation on a detection step, the method makes pre-segmentation, which can be further used for recognition purposes. Another important feature of the proposed approach is that there are no needs to use a running window as well as a features pyramid in order to detect the objects of different sizes.

  14. Upconversion based continuous-wave mid-infrared detection

    DEFF Research Database (Denmark)

    Tidemand-Lichtenberg, Peter; Dam, Jeppe Seidelin; Pedersen, Christian

    2013-01-01

    We present theoretical and experimental work on upconversion based mid-wavelength infrared detection using silicon detectors without the need for cryogenic cooling. We consider both multi-spectral imaging and point spectroscopy targeting several specific applications.......We present theoretical and experimental work on upconversion based mid-wavelength infrared detection using silicon detectors without the need for cryogenic cooling. We consider both multi-spectral imaging and point spectroscopy targeting several specific applications....

  15. Voltage Sag Source Location Based on Instantaneous Energy Detection

    DEFF Research Database (Denmark)

    Chen, Zhe; Kong, Wei; Dong, Xinzhou

    2008-01-01

    Voltage sag is a major power quality problem, which could disrupt the operation of voltage-sensitive equipment. This paper presents the method based on variation components-based instantaneous energy for voltage sag source detection. Simulations have been performed to provide the thorough analysis...... for system with distributed generation units. The studies show that the presented method can effectively detect the location of voltage sag source....

  16. Machine Learning Based Classifier for Falsehood Detection

    Science.gov (United States)

    Mallikarjun, H. M.; Manimegalai, P., Dr.; Suresh, H. N., Dr.

    2017-08-01

    The investigation of physiological techniques for Falsehood identification tests utilizing the enthusiastic aggravations started as a part of mid 1900s. The need of Falsehood recognition has been a piece of our general public from hundreds of years back. Different requirements drifted over the general public raising the need to create trick evidence philosophies for Falsehood identification. The established similar addressing tests have been having a tendency to gather uncertain results against which new hearty strategies are being explored upon for acquiring more productive Falsehood discovery set up. Electroencephalography (EEG) is a non-obtrusive strategy to quantify the action of mind through the anodes appended to the scalp of a subject. Electroencephalogram is a record of the electric signs produced by the synchronous activity of mind cells over a timeframe. The fundamental goal is to accumulate and distinguish the important information through this action which can be acclimatized for giving surmising to Falsehood discovery in future analysis. This work proposes a strategy for Falsehood discovery utilizing EEG database recorded on irregular people of various age gatherings and social organizations. The factual investigation is directed utilizing MATLAB v-14. It is a superior dialect for specialized registering which spares a considerable measure of time with streamlined investigation systems. In this work center is made on Falsehood Classification by Support Vector Machine (SVM). 72 Samples are set up by making inquiries from standard poll with a Wright and wrong replies in a diverse era from the individual in wearable head unit. 52 samples are trained and 20 are tested. By utilizing Bluetooth based Neurosky’s Mindwave kit, brain waves are recorded and qualities are arranged appropriately. In this work confusion matrix is derived by matlab programs and accuracy of 56.25 % is achieved.

  17. [Detecting fire smoke based on the multispectral image].

    Science.gov (United States)

    Wei, Ying-Zhuo; Zhang, Shao-Wu; Liu, Yan-Wei

    2010-04-01

    Smoke detection is very important for preventing forest-fire in the fire early process. Because the traditional technologies based on video and image processing are easily affected by the background dynamic information, three limitations exist in these technologies, i. e. lower anti-interference ability, higher false detection rate and the fire smoke and water fog being not easily distinguished. A novel detection method for detecting smoke based on the multispectral image was proposed in the present paper. Using the multispectral digital imaging technique, the multispectral image series of fire smoke and water fog were obtained in the band scope of 400 to 720 nm, and the images were divided into bins. The Euclidian distance among the bins was taken as a measurement for showing the difference of spectrogram. After obtaining the spectral feature vectors of dynamic region, the regions of fire smoke and water fog were extracted according to the spectrogram feature difference between target and background. The indoor and outdoor experiments show that the smoke detection method based on multispectral image can be applied to the smoke detection, which can effectively distinguish the fire smoke and water fog. Combined with video image processing method, the multispectral image detection method can also be applied to the forest fire surveillance, reducing the false alarm rate in forest fire detection.

  18. BRAFV600E immunohistochemistry in conjunction with mismatch repair status predicts survival in patients with colorectal cancer.

    Science.gov (United States)

    Toon, Christopher W; Chou, Angela; DeSilva, Keshani; Chan, Joseph; Patterson, Jillian; Clarkson, Adele; Sioson, Loretta; Jankova, Lucy; Gill, Anthony J

    2014-05-01

    Immunohistochemistry has recently been validated for the detection of the BRAFV600E mutation across a range of tumor types. In colorectal carcinoma, the presence of the BRAFV600E mutation can be used to virtually exclude Lynch syndrome in mismatch repair-deficient tumors. In mismatch repair-proficient tumors, BRAFV600E mutation assessed by molecular methods has been proposed as a poor prognostic factor. We investigated whether combined BRAFV600E and mismatch repair status assessment by immunohistochemistry alone can be used as a prognostic marker in the routine clinical setting. We performed immunohistochemistry for BRAFV600E, MLH1, PMS2, MSH2, and MSH6 on 1426 consecutive unselected colorectal carcinomas. Ninety-one (6.4%) carcinomas were mismatch repair-proficient and BRAFV600E mutant, and these tumors demonstrated a significantly worse 5-year survival of 49.7% compared with mismatch repair-proficient BRAF wild type (74.1% of tumors, 65.4% survival), mismatch repair-deficient BRAFV600E mutant (12.9% of tumors, 70.1% survival), and mismatch repair-deficient BRAF wild type (6.6% of tumors, 73.6% survival). The poor survival was confirmed by univariate analysis (Pimmunohistochemistry can be used as a powerful predictor of all-cause survival.

  19. Immigrants' Educational Mismatch and the Penalty of Over-Education

    Science.gov (United States)

    Kalfa, Eleni; Piracha, Matloob

    2017-01-01

    This paper analyses immigrants' educational mismatch and its impact on wages in Spain. The incidence of immigrants' education-occupation mismatch in the Spanish labour market can largely be explained by the mismatch in the last job held in the home country. The probability of having been over-educated in the home country has a higher effect on the…

  20. An Improved Wavelet‐Based Multivariable Fault Detection Scheme

    KAUST Repository

    Harrou, Fouzi

    2017-07-06

    Data observed from environmental and engineering processes are usually noisy and correlated in time, which makes the fault detection more difficult as the presence of noise degrades fault detection quality. Multiscale representation of data using wavelets is a powerful feature extraction tool that is well suited to denoising and decorrelating time series data. In this chapter, we combine the advantages of multiscale partial least squares (MSPLSs) modeling with those of the univariate EWMA (exponentially weighted moving average) monitoring chart, which results in an improved fault detection system, especially for detecting small faults in highly correlated, multivariate data. Toward this end, we applied EWMA chart to the output residuals obtained from MSPLS model. It is shown through simulated distillation column data the significant improvement in fault detection can be obtained by using the proposed methods as compared to the use of the conventional partial least square (PLS)‐based Q and EWMA methods and MSPLS‐based Q method.

  1. Transistor-based particle detection systems and methods

    Science.gov (United States)

    Jain, Ankit; Nair, Pradeep R.; Alam, Muhammad Ashraful

    2015-06-09

    Transistor-based particle detection systems and methods may be configured to detect charged and non-charged particles. Such systems may include a supporting structure contacting a gate of a transistor and separating the gate from a dielectric of the transistor, and the transistor may have a near pull-in bias and a sub-threshold region bias to facilitate particle detection. The transistor may be configured to change current flow through the transistor in response to a change in stiffness of the gate caused by securing of a particle to the gate, and the transistor-based particle detection system may configured to detect the non-charged particle at least from the change in current flow.

  2. The effect of S-substitution at the O6-guanine site on the structure and dynamics of a DNA oligomer containing a G:T mismatch.

    Science.gov (United States)

    Moore, Elaine Ann; Xu, Yao-Zhong

    2017-01-01

    The effect of S-substitution on the O6 guanine site of a 13-mer DNA duplex containing a G:T mismatch is studied using molecular dynamics. The structure, dynamic evolution and hydration of the S-substituted duplex are compared with those of a normal duplex, a duplex with S-substitution on guanine, but no mismatch and a duplex with just a G:T mismatch. The S-substituted mismatch leads to cell death rather than repair. One suggestion is that the G:T mismatch recognition protein recognises the S-substituted mismatch (GS:T) as G:T. This leads to a cycle of futile repair ending in DNA breakage and cell death. We find that some structural features of the helix are similar for the duplex with the G:T mismatch and that with the S-substituted mismatch, but differ from the normal duplex, notably the helical twist. These differences arise from the change in the hydrogen-bonding pattern of the base pair. However a marked feature of the S-substituted G:T mismatch duplex is a very large opening. This showed considerable variability. It is suggested that this enlarged opening would lend support to an alternative model of cell death in which the mismatch protein attaches to thioguanine and activates downstream damage-response pathways. Attack on the sulphur by reactive oxygen species, also leading to cell death, would also be aided by the large, variable opening.

  3. The effect of S-substitution at the O6-guanine site on the structure and dynamics of a DNA oligomer containing a G:T mismatch.

    Directory of Open Access Journals (Sweden)

    Elaine Ann Moore

    Full Text Available The effect of S-substitution on the O6 guanine site of a 13-mer DNA duplex containing a G:T mismatch is studied using molecular dynamics. The structure, dynamic evolution and hydration of the S-substituted duplex are compared with those of a normal duplex, a duplex with S-substitution on guanine, but no mismatch and a duplex with just a G:T mismatch. The S-substituted mismatch leads to cell death rather than repair. One suggestion is that the G:T mismatch recognition protein recognises the S-substituted mismatch (GS:T as G:T. This leads to a cycle of futile repair ending in DNA breakage and cell death. We find that some structural features of the helix are similar for the duplex with the G:T mismatch and that with the S-substituted mismatch, but differ from the normal duplex, notably the helical twist. These differences arise from the change in the hydrogen-bonding pattern of the base pair. However a marked feature of the S-substituted G:T mismatch duplex is a very large opening. This showed considerable variability. It is suggested that this enlarged opening would lend support to an alternative model of cell death in which the mismatch protein attaches to thioguanine and activates downstream damage-response pathways. Attack on the sulphur by reactive oxygen species, also leading to cell death, would also be aided by the large, variable opening.

  4. Region duplication forgery detection technique based on SURF and HAC.

    Science.gov (United States)

    Mishra, Parul; Mishra, Nishchol; Sharma, Sanjeev; Patel, Ravindra

    2013-01-01

    Region duplication forgery detection is a special type of forgery detection approach and widely used research topic under digital image forensics. In copy move forgery, a specific area is copied and then pasted into any other region of the image. Due to the availability of sophisticated image processing tools, it becomes very hard to detect forgery with naked eyes. From the forged region of an image no visual clues are often detected. For making the tampering more robust, various transformations like scaling, rotation, illumination changes, JPEG compression, noise addition, gamma correction, and blurring are applied. So there is a need for a method which performs efficiently in the presence of all such attacks. This paper presents a detection method based on speeded up robust features (SURF) and hierarchical agglomerative clustering (HAC). SURF detects the keypoints and their corresponding features. From these sets of keypoints, grouping is performed on the matched keypoints by HAC that shows copied and pasted regions.

  5. DDoS Attack Detection Algorithms Based on Entropy Computing

    Science.gov (United States)

    Li, Liying; Zhou, Jianying; Xiao, Ning

    Distributed Denial of Service (DDoS) attack poses a severe threat to the Internet. It is difficult to find the exact signature of attacking. Moreover, it is hard to distinguish the difference of an unusual high volume of traffic which is caused by the attack or occurs when a huge number of users occasionally access the target machine at the same time. The entropy detection method is an effective method to detect the DDoS attack. It is mainly used to calculate the distribution randomness of some attributes in the network packets' headers. In this paper, we focus on the detection technology of DDoS attack. We improve the previous entropy detection algorithm, and propose two enhanced detection methods based on cumulative entropy and time, respectively. Experiment results show that these methods could lead to more accurate and effective DDoS detection.

  6. Laser-based instrumentation for the detection of chemical agents

    International Nuclear Information System (INIS)

    Hartford, A. Jr.; Sander, R.K.; Quigley, G.P.; Radziemski, L.J.; Cremers, D.A.

    1982-01-01

    Several laser-based techniques are being evaluated for the remote, point, and surface detection of chemical agents. Among the methods under investigation are optoacoustic spectroscopy, laser-induced breakdown spectroscopy (LIBS), and synchronous detection of laser-induced fluorescence (SDLIF). Optoacoustic detection has already been shown to be capable of extremely sensitive point detection. Its application to remote sensing of chemical agents is currently being evaluated. Atomic emission from the region of a laser-generated plasma has been used to identify the characteristic elements contained in nerve (P and F) and blister (S and Cl) agents. Employing this LIBS approach, detection of chemical agent simulants dispersed in air and adsorbed on a variety of surfaces has been achieved. Synchronous detection of laser-induced fluorescence provides an attractive alternative to conventional LIF, in that an artificial narrowing of the fluorescence emission is obtained. The application of this technique to chemical agent simulants has been successfully demonstrated. 19 figures

  7. Image Fakery Detection Based on Singular Value Decomposition

    Directory of Open Access Journals (Sweden)

    T. Basaruddin

    2009-11-01

    Full Text Available The growing of image processing technology nowadays make it easier for user to modify and fake the images. Image fakery is a process to manipulate part or whole areas of image either in it content or context with the help of digital image processing techniques. Image fakery is barely unrecognizable because the fake image is looking so natural. Yet by using the numerical computation technique it is able to detect the evidence of fake image. This research is successfully applied the singular value decomposition method to detect image fakery. The image preprocessing algorithm prior to the detection process yields two vectors orthogonal to the singular value vector which are important to detect fake image. The result of experiment to images in several conditions successfully detects the fake images with threshold value 0.2. Singular value decomposition-based detection of image fakery can be used to investigate fake image modified from original image accurately.

  8. Region Duplication Forgery Detection Technique Based on SURF and HAC

    Directory of Open Access Journals (Sweden)

    Parul Mishra

    2013-01-01

    Full Text Available Region duplication forgery detection is a special type of forgery detection approach and widely used research topic under digital image forensics. In copy move forgery, a specific area is copied and then pasted into any other region of the image. Due to the availability of sophisticated image processing tools, it becomes very hard to detect forgery with naked eyes. From the forged region of an image no visual clues are often detected. For making the tampering more robust, various transformations like scaling, rotation, illumination changes, JPEG compression, noise addition, gamma correction, and blurring are applied. So there is a need for a method which performs efficiently in the presence of all such attacks. This paper presents a detection method based on speeded up robust features (SURF and hierarchical agglomerative clustering (HAC. SURF detects the keypoints and their corresponding features. From these sets of keypoints, grouping is performed on the matched keypoints by HAC that shows copied and pasted regions.

  9. An Incremental Support Vector Machine based Speech Activity Detection Algorithm.

    Science.gov (United States)

    Xianbo, Xiao; Guangshu, Hu

    2005-01-01

    Traditional voice activity detection algorithms are mostly threshold-based or statistical model-based. All those methods are absent of the ability to react quickly to variations of environments. This paper describes an incremental SVM (Support Vector Machine) method for speech activity detection. The proposed incremental procedure makes it adaptive to variation of environments and the special construction of incremental training data set decreases computing consumption effectively. Experiments results demonstrated its higher end point detection accuracy. Further work will be focused on decreasing computing consumption and importing multi-class SVM classifiers.

  10. Computer-based instrumentation for partial discharge detection in GIS

    International Nuclear Information System (INIS)

    Md Enamul Haque; Ahmad Darus; Yaacob, M.M.; Halil Hussain; Feroz Ahmed

    2000-01-01

    Partial discharge is one of the prominent indicators of defects and insulation degradation in a Gas Insulated Switchgear (GIS). Partial discharges (PD) have a harmful effect on the life of insulation of high voltage equipment. The PD detection using acoustic technique and subsequent analysis is currently an efficient method of performing non-destructive testing of GIS apparatus. A low cost PC-based acoustic PD detection instrument has been developed for the non-destructive diagnosis of GIS. This paper describes the development of a PC-based instrumentation system for partial discharge detection in GIS and some experimental results have also presented. (Author)

  11. A novel line segment detection algorithm based on graph search

    Science.gov (United States)

    Zhao, Hong-dan; Liu, Guo-ying; Song, Xu

    2018-02-01

    To overcome the problem of extracting line segment from an image, a method of line segment detection was proposed based on the graph search algorithm. After obtaining the edge detection result of the image, the candidate straight line segments are obtained in four directions. For the candidate straight line segments, their adjacency relationships are depicted by a graph model, based on which the depth-first search algorithm is employed to determine how many adjacent line segments need to be merged. Finally we use the least squares method to fit the detected straight lines. The comparative experimental results verify that the proposed algorithm has achieved better results than the line segment detector (LSD).

  12. Research of detection depth for graphene-based optical sensor

    Science.gov (United States)

    Yang, Yong; Sun, Jialve; Liu, Lu; Zhu, Siwei; Yuan, Xiaocong

    2018-03-01

    Graphene-based optical sensors have been developed for research into the biological intercellular refractive index (RI) because they offer greater detection depths than those provided by the surface plasmon resonance technique. In this Letter, we propose an experimental approach for measurement of the detection depth in a graphene-based optical sensor system that uses transparent polydimethylsiloxane layers with different thicknesses. The experimental results show that detection depths of 2.5 μm and 3 μm can be achieved at wavelengths of 532 nm and 633 nm, respectively. These results prove that graphene-based optical sensors can realize long-range RI detection and are thus promising for use as tools in the biological cell detection field. Additionally, we analyze the factors that influence the detection depth and provide a feasible approach for detection depth control based on adjustment of the wavelength and the angle of incidence. We believe that this approach will be useful in RI tomography applications.

  13. Enhanced sensing of dengue virus DNA detection using O2 plasma treated-silicon nanowire based electrical biosensor

    International Nuclear Information System (INIS)

    Rahman, S.F.A.; Yusof, N.A.; Hashim, U.; Hushiarian, R.; Nuzaihan, M.N.M.; Hamidon, M.N.; Zawawi, R.M.; Fathil, M.F.M.

    2016-01-01

    Dengue Virus (DENV) has become one of the most serious arthropod-borne viral diseases, causing death globally. The existing methods for DENV detection suffer from the late stage treatment due to antibodies-based detection which is feasible only after five days following the onset of the illness. Here, we demonstrated the highly effective molecular electronic based detection utilizing silicon nanowire (SiNW) integrated with standard complementary metal-oxide-semiconductor (CMOS) process as a sensing device for detecting deoxyribonucleic acid (DNA) related to DENV in an early stage diagnosis. To transform the fabricated devices as a functional sensing element, three-step procedure consist of SiNW surface modification, DNA immobilization and DNA hybridization were employed. The detection principle works by detecting the changes in current of SiNW which bridge the source and drain terminal to sense the immobilization of probe DNA and their hybridization with target DNA. The oxygen (O 2 ) plasma was proposed as an effective strategy for increasing the binding amounts of target DNA by modified the SiNW surface. It was found that the detection limit of the optimized O 2 plasma treated-SiNW device could be reduced to 1.985 × 10 −14  M with a linear detection range of the sequence-specific DNA from 1.0 × 10 −9  M to 1.0 × 10 −13  M. In addition, the developed biosensor device was able to discriminate between complementary, single mismatch and non-complementary DNA sequences. This highly sensitive assay was then applied to the detection of reverse transcription-polymerase chain reaction (RT-PCR) product of DENV-DNA, making it as a potential method for disease diagnosis through electrical biosensor. - Highlights: • Molecular electronic detection of Dengue Virus (DENV) DNA using SiNW biosensor is presented. • Oxygen plasma surface treatment as an enhancer technique for device sensitivity is highlighted. • The limit of detection (LoD) as low as 1.985

  14. Enhanced sensing of dengue virus DNA detection using O{sub 2} plasma treated-silicon nanowire based electrical biosensor

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, S.F.A., E-mail: siti_fatimah0410@yahoo.com [Institute of Advanced Technology, Universiti Putra Malaysia, 43400, UPM, Serdang, Selangor (Malaysia); Yusof, N.A., E-mail: azahy@upm.edu.my [Institute of Advanced Technology, Universiti Putra Malaysia, 43400, UPM, Serdang, Selangor (Malaysia); Chemistry Department, Faculty of Science, Universiti Putra Malaysia, 43400, UPM, Serdang, Selangor (Malaysia); Hashim, U. [Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000, Kangar, Perlis (Malaysia); Hushiarian, R. [La Trobe Institute for Molecular Science, La Trobe University, Victoria, 3086 (Australia); Nuzaihan, M.N.M. [Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000, Kangar, Perlis (Malaysia); Hamidon, M.N. [Institute of Advanced Technology, Universiti Putra Malaysia, 43400, UPM, Serdang, Selangor (Malaysia); Zawawi, R.M. [Chemistry Department, Faculty of Science, Universiti Putra Malaysia, 43400, UPM, Serdang, Selangor (Malaysia); Fathil, M.F.M. [Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000, Kangar, Perlis (Malaysia)

    2016-10-26

    Dengue Virus (DENV) has become one of the most serious arthropod-borne viral diseases, causing death globally. The existing methods for DENV detection suffer from the late stage treatment due to antibodies-based detection which is feasible only after five days following the onset of the illness. Here, we demonstrated the highly effective molecular electronic based detection utilizing silicon nanowire (SiNW) integrated with standard complementary metal-oxide-semiconductor (CMOS) process as a sensing device for detecting deoxyribonucleic acid (DNA) related to DENV in an early stage diagnosis. To transform the fabricated devices as a functional sensing element, three-step procedure consist of SiNW surface modification, DNA immobilization and DNA hybridization were employed. The detection principle works by detecting the changes in current of SiNW which bridge the source and drain terminal to sense the immobilization of probe DNA and their hybridization with target DNA. The oxygen (O{sub 2}) plasma was proposed as an effective strategy for increasing the binding amounts of target DNA by modified the SiNW surface. It was found that the detection limit of the optimized O{sub 2} plasma treated-SiNW device could be reduced to 1.985 × 10{sup −14} M with a linear detection range of the sequence-specific DNA from 1.0 × 10{sup −9} M to 1.0 × 10{sup −13} M. In addition, the developed biosensor device was able to discriminate between complementary, single mismatch and non-complementary DNA sequences. This highly sensitive assay was then applied to the detection of reverse transcription-polymerase chain reaction (RT-PCR) product of DENV-DNA, making it as a potential method for disease diagnosis through electrical biosensor. - Highlights: • Molecular electronic detection of Dengue Virus (DENV) DNA using SiNW biosensor is presented. • Oxygen plasma surface treatment as an enhancer technique for device sensitivity is highlighted. • The limit of detection (Lo

  15. Smart phone based bacterial detection using bio functionalized fluorescent nanoparticles

    International Nuclear Information System (INIS)

    Rajendran, Vinoth Kumar; Bakthavathsalam, Padmavathy; Ali, Baquir Mohammed Jaffar

    2014-01-01

    We are describing immunochromatographic test strips with smart phone-based fluorescence readout. They are intended for use in the detection of the foodborne bacterial pathogens Salmonella spp. and Escherichia coli O157. Silica nanoparticles (SiNPs) were doped with FITC and Ru(bpy), conjugated to the respective antibodies, and then used in a conventional lateral flow immunoassay (LFIA). Fluorescence was recorded by inserting the nitrocellulose strip into a smart phone-based fluorimeter consisting of a light weight (40 g) optical module containing an LED light source, a fluorescence filter set and a lens attached to the integrated camera of the cell phone in order to acquire high-resolution fluorescence images. The images were analysed by exploiting the quick image processing application of the cell phone and enable the detection of pathogens within few minutes. This LFIA is capable of detecting pathogens in concentrations as low as 10 5 cfu mL −1 directly from test samples without pre-enrichment. The detection is one order of magnitude better compared to gold nanoparticle-based LFIAs under similar condition. The successful combination of fluorescent nanoparticle-based pathogen detection by LFIAs with a smart phone-based detection platform has resulted in a portable device with improved diagnosis features and having potential application in diagnostics and environmental monitoring. (author)

  16. Combining Host-based and network-based intrusion detection system

    African Journals Online (AJOL)

    These attacks were simulated using hping. The proposed system is implemented in Java. The results show that the proposed system is able to detect attacks both from within (host-based) and outside sources (network-based). Key Words: Intrusion Detection System (IDS), Host-based, Network-based, Signature, Security log.

  17. Multicriteria Similarity-Based Anomaly Detection Using Pareto Depth Analysis.

    Science.gov (United States)

    Hsiao, Ko-Jen; Xu, Kevin S; Calder, Jeff; Hero, Alfred O

    2016-06-01

    We consider the problem of identifying patterns in a data set that exhibits anomalous behavior, often referred to as anomaly detection. Similarity-based anomaly detection algorithms detect abnormally large amounts of similarity or dissimilarity, e.g., as measured by the nearest neighbor Euclidean distances between a test sample and the training samples. In many application domains, there may not exist a single dissimilarity measure that captures all possible anomalous patterns. In such cases, multiple dissimilarity measures can be defined, including nonmetric measures, and one can test for anomalies by scalarizing using a nonnegative linear combination of them. If the relative importance of the different dissimilarity measures are not known in advance, as in many anomaly detection applications, the anomaly detection algorithm may need to be executed multiple times with different choices of weights in the linear combination. In this paper, we propose a method for similarity-based anomaly detection using a novel multicriteria dissimilarity measure, the Pareto depth. The proposed Pareto depth analysis (PDA) anomaly detection algorithm uses the concept of Pareto optimality to detect anomalies under multiple criteria without having to run an algorithm multiple times with different choices of weights. The proposed PDA approach is provably better than using linear combinations of the criteria, and shows superior performance on experiments with synthetic and real data sets.

  18. A physiology-based seizure detection system for multichannel EEG.

    Directory of Open Access Journals (Sweden)

    Chia-Ping Shen

    Full Text Available BACKGROUND: Epilepsy is a common chronic neurological disorder characterized by recurrent unprovoked seizures. Electroencephalogram (EEG signals play a critical role in the diagnosis of epilepsy. Multichannel EEGs contain more information than do single-channel EEGs. Automatic detection algorithms for spikes or seizures have traditionally been implemented on single-channel EEG, and algorithms for multichannel EEG are unavailable. METHODOLOGY: This study proposes a physiology-based detection system for epileptic seizures that uses multichannel EEG signals. The proposed technique was tested on two EEG data sets acquired from 18 patients. Both unipolar and bipolar EEG signals were analyzed. We employed sample entropy (SampEn, statistical values, and concepts used in clinical neurophysiology (e.g., phase reversals and potential fields of a bipolar EEG to extract the features. We further tested the performance of a genetic algorithm cascaded with a support vector machine and post-classification spike matching. PRINCIPAL FINDINGS: We obtained 86.69% spike detection and 99.77% seizure detection for Data Set I. The detection system was further validated using the model trained by Data Set I on Data Set II. The system again showed high performance, with 91.18% detection of spikes and 99.22% seizure detection. CONCLUSION: We report a de novo EEG classification system for seizure and spike detection on multichannel EEG that includes physiology-based knowledge to enhance the performance of this type of system.

  19. Differential Characteristics Based Iterative Multiuser Detection for Wireless Sensor Networks.

    Science.gov (United States)

    Chen, Xiaoguang; Jiang, Xu; Wu, Zhilu; Zhuang, Shufeng

    2017-02-16

    High throughput, low latency and reliable communication has always been a hot topic for wireless sensor networks (WSNs) in various applications. Multiuser detection is widely used to suppress the bad effect of multiple access interference in WSNs. In this paper, a novel multiuser detection method based on differential characteristics is proposed to suppress multiple access interference. The proposed iterative receive method consists of three stages. Firstly, a differential characteristics function is presented based on the optimal multiuser detection decision function; then on the basis of differential characteristics, a preliminary threshold detection is utilized to find the potential wrongly received bits; after that an error bit corrector is employed to correct the wrong bits. In order to further lower the bit error ratio (BER), the differential characteristics calculation, threshold detection and error bit correction process described above are iteratively executed. Simulation results show that after only a few iterations the proposed multiuser detection method can achieve satisfactory BER performance. Besides, BER and near far resistance performance are much better than traditional suboptimal multiuser detection methods. Furthermore, the proposed iterative multiuser detection method also has a large system capacity.

  20. A Portable Pesticide Residues Detection Instrument Based on Impedance Immunosensor

    Directory of Open Access Journals (Sweden)

    Jiang Ding

    2014-06-01

    Full Text Available In this paper, a design of portable pesticide residues detection instrument was presented based on an impedance immunosensor. The immunosensor exploited the novel multilayer films based on Au nanoparticles (AuNPs and polyaniline/carboxylated multiwall carbon nanotubes- chitosan nanocomposite (PANI/MWCNTs/CS. The detection principle of the instrument was based on the electrochemical characteristic of antigen-specific antibody immune response. With a stronger signal generated from the antigen-specific antibody immune response, the signal detection circuit was designed more easily. We integrated immunosensor and signal detection circuit to fabricate pesticide residues detection instrument. This proposed instrument could realize the rapid detection of pesticide residues in fruits and vegetables with automatic data processing and presented the result on the spot. The impedance test error was less than 5 %. The results showed that the proposed instrument had a good consistence compared with the traditional analytical methods. Thus, it would be a promising rapid detection instrument for pesticide residues in agricultural products.

  1. Somatosensory mismatch response in young and elderly adults

    Directory of Open Access Journals (Sweden)

    Juho M. Strömmer

    2014-10-01

    Full Text Available Aging is associated with cognitive decline and alterations in early perceptual processes. Studies in the auditory and visual modalities have shown that the mismatch negativity (or the mismatch response, MMR, an event-related potential (ERP elicited by a deviant stimulus in a background of homogenous events, diminishes with aging and cognitive decline. However, the effects of aging on the somatosensory MMR are not known. In the current study, we recorded ERPs to electrical pulses to different fingers of the left hand in a passive oddball experiment in young (22–36 years and elderly (66–95 years adults engaged in a visual task. The MMR was found to deviants as compared to standards at two latency ranges: 180–220 ms and 250–290 ms post-stimulus onset. At 180–220 ms, within the young, the MMR was found at medial electrode sites, whereas aged did not show any amplitude difference between the stimulus types at the same latency range. At 250–290 ms, the MMR was evident with attenuated amplitude and narrowed scalp distribution among aged (Fz compared to young (fronto-centrally and lateral parietal sites. Hence, the results reveal that the somatosensory change detection mechanism is altered in aging. The somatosensory MMR can be used as a reliable measure of age-related changes in sensory-cognitive functions.

  2. Distributed Iterative Multiuser Detection through Base Station Cooperation

    Directory of Open Access Journals (Sweden)

    Shahid Khattak

    2008-08-01

    Full Text Available This paper deals with multiuser detection through base station cooperation in an uplink, interference-limited, high frequency reuse scenario. Distributed iterative detection (DID is an interference mitigation technique in which the base stations at different geographical locations exchange detected data iteratively while performing separate detection and decoding of their received data streams. This paper explores possible DID receive strategies and proposes to exchange between base stations only the processed information for their associated mobile terminals. The resulting backhaul traffic is considerably lower than that of existing cooperative multiuser detection strategies. Single-antenna interference cancellation techniques are employed to generate local estimates of the dominant interferers at each base station, which are then combined with their independent received copies from other base stations, resulting in more effective interference suppression. Since hard information bits or quantized log-likelihood ratios (LLRs are transferred, we investigate the effect of quantization of the LLR values with the objective of further reducing the backhaul traffic. Our findings show that schemes based on nonuniform quantization of the “soft bits” allow for reducing the backhaul to 1–2 exchanged bits/coded bit.

  3. Distributed Iterative Multiuser Detection through Base Station Cooperation

    Directory of Open Access Journals (Sweden)

    Khattak Shahid

    2008-01-01

    Full Text Available Abstract This paper deals with multiuser detection through base station cooperation in an uplink, interference-limited, high frequency reuse scenario. Distributed iterative detection (DID is an interference mitigation technique in which the base stations at different geographical locations exchange detected data iteratively while performing separate detection and decoding of their received data streams. This paper explores possible DID receive strategies and proposes to exchange between base stations only the processed information for their associated mobile terminals. The resulting backhaul traffic is considerably lower than that of existing cooperative multiuser detection strategies. Single-antenna interference cancellation techniques are employed to generate local estimates of the dominant interferers at each base station, which are then combined with their independent received copies from other base stations, resulting in more effective interference suppression. Since hard information bits or quantized log-likelihood ratios (LLRs are transferred, we investigate the effect of quantization of the LLR values with the objective of further reducing the backhaul traffic. Our findings show that schemes based on nonuniform quantization of the "soft bits" allow for reducing the backhaul to 1–2 exchanged bits/coded bit.

  4. Genome instability of mis-match repair and its role in carcinogenesis due to radiation

    Energy Technology Data Exchange (ETDEWEB)

    Munakata, Nobuo; Morohoshi, Fumiko [National Cancer Center, Tokyo (Japan). Research Inst

    1999-02-01

    Homologue genes, mutS and mutL have been known as a key gene for mismatch repair in E. coli. In this study, identification of such homologue genes in the nematode was attempted using caenorhabditis elegans and three kinds of mutS homologues (mshG, mshZ and mshF) and 2 kinds of mutL ones were identified. From after isolation of these genes, base sequences were analyzed. Then, an insertion mutant in which Tcl transposon is inserted in Exon 13 positioned at the center of mshF was screened and its homozygote where breakage of transposon in somatic cells occurred frequently was obtained and its morphological changes were not significant. In the nematoda, we detected a highly conserved domain in mutS family gene, which is commonly present in yeast and human genes. Based on the amino acid sequence of this domain, four kinds of primers were constructed for PCR reaction using the whole DNA from the nematoda as a template and four DNA fragments of which sizes were almost corresponding to the homologue proteins were produced. From screening of Tc1 insertion mutant for 8 mismatch repair genes, three strains; mshF, rqhW and RqhY were obtained and the gene structures and the positions of Tc1 insertion in these strains were determined. The sensitivities to ionizing radiation, UV and alkyl reagent of these strains were not significantly different from those of the wild strain. (M.N.)

  5. Home Camera-Based Fall Detection System for the Elderly

    Directory of Open Access Journals (Sweden)

    Koldo de Miguel

    2017-12-01

    Full Text Available Falls are the leading cause of injury and death in elderly individuals. Unfortunately, fall detectors are typically based on wearable devices, and the elderly often forget to wear them. In addition, fall detectors based on artificial vision are not yet available on the market. In this paper, we present a new low-cost fall detector for smart homes based on artificial vision algorithms. Our detector combines several algorithms (background subtraction, Kalman filtering and optical flow as input to a machine learning algorithm with high detection accuracy. Tests conducted on over 50 different fall videos have shown a detection ratio of greater than 96%.

  6. Home Camera-Based Fall Detection System for the Elderly.

    Science.gov (United States)

    de Miguel, Koldo; Brunete, Alberto; Hernando, Miguel; Gambao, Ernesto

    2017-12-09

    Falls are the leading cause of injury and death in elderly individuals. Unfortunately, fall detectors are typically based on wearable devices, and the elderly often forget to wear them. In addition, fall detectors based on artificial vision are not yet available on the market. In this paper, we present a new low-cost fall detector for smart homes based on artificial vision algorithms. Our detector combines several algorithms (background subtraction, Kalman filtering and optical flow) as input to a machine learning algorithm with high detection accuracy. Tests conducted on over 50 different fall videos have shown a detection ratio of greater than 96%.

  7. A vision based row detection system for sugar beet

    NARCIS (Netherlands)

    Bakker, T.; Wouters, H.; Asselt, van C.J.; Bontsema, J.; Tang, L.; Müller, J.; Straten, van G.

    2008-01-01

    One way of guiding autonomous vehicles through the field is using a vision based row detection system. A new approach for row recognition is presented which is based on grey-scale Hough transform on intelligently merged images resulting in a considerable improvement of the speed of image processing.

  8. A Labeled Data Set For Flow-based Intrusion Detection

    NARCIS (Netherlands)

    Sperotto, Anna; Sadre, R.; van Vliet, Frank; Pras, Aiko; Nunzi, Giorgio; Scoglio, Caterina; Li, Xing

    2009-01-01

    Flow-based intrusion detection has recently become a promising security mechanism in high speed networks (1-10 Gbps). Despite the richness in contributions in this field, benchmarking of flow-based IDS is still an open issue. In this paper, we propose the first publicly available, labeled data set

  9. Dust storm detection using random forests and physical-based ...

    Indian Academy of Sciences (India)

    This paper investigates the capability of two physical-based methods, and random forests (RF) classifier, for the first time, to detect dust storms using MODIS imagery. Since the physical-based approaches are empirical, they suffer from certain drawbacks such as high variability of thresholds depending on the underlying ...

  10. Smartphone-based low light detection for bioluminescence application

    Science.gov (United States)

    We report a smartphone-based device and associated imaging-processing algorithm to maximize the sensitivity of standard smartphone cameras, that can detect the presence of single-digit pW of radiant flux intensity. The proposed hardware and software, called bioluminescent-based analyte quantitation ...

  11. RANDOM FOREST BASED MISFIRE DETECTION USING KONONENKO DISCRETISER

    Directory of Open Access Journals (Sweden)

    S. Babu Devasenapati

    2012-01-01

    Full Text Available This paper evaluates the use of random forest (RF as a tool for misfire detection using statistical features. The engine block vibration contains hidden information about the events occurring inside the engine. Misfire detection was achieved by processing the vibration signals acquired from the engine using a piezoelectric accelerometer. The hidden information regarding misfire was decoded using feature extraction techniques. The effect of Kononenko based discretiser as feature size reduction tool and Correlation-based Feature Selection (CFS based feature subset selection is analysed for performance improvement in the RF model. The random forest based model is found to have a consistent high classification accuracy of around 90% when designed as a multi class ,ode and reaches 100% when the conditions are clubbed to simulate a two-class mode . From the results obtained the authors conclude that the combination of statistical features and RF algorithm is well suited for detection of misfire in spark ignition engines.

  12. An Android malware detection system based on machine learning

    Science.gov (United States)

    Wen, Long; Yu, Haiyang

    2017-08-01

    The Android smartphone, with its open source character and excellent performance, has attracted many users. However, the convenience of the Android platform also has motivated the development of malware. The traditional method which detects the malware based on the signature is unable to detect unknown applications. The article proposes a machine learning-based lightweight system that is capable of identifying malware on Android devices. In this system we extract features based on the static analysis and the dynamitic analysis, then a new feature selection approach based on principle component analysis (PCA) and relief are presented in the article to decrease the dimensions of the features. After that, a model will be constructed with support vector machine (SVM) for classification. Experimental results show that our system provides an effective method in Android malware detection.

  13. Robust facial landmark detection based on initializing multiple poses

    Directory of Open Access Journals (Sweden)

    Xin Chai

    2016-10-01

    Full Text Available For robot systems, robust facial landmark detection is the first and critical step for face-based human identification and facial expression recognition. In recent years, the cascaded-regression-based method has achieved excellent performance in facial landmark detection. Nevertheless, it still has certain weakness, such as high sensitivity to the initialization. To address this problem, regression based on multiple initializations is established in a unified model; face shapes are then estimated independently according to these initializations. With a ranking strategy, the best estimate is selected as the final output. Moreover, a face shape model based on restricted Boltzmann machines is built as a constraint to improve the robustness of ranking. Experiments on three challenging datasets demonstrate the effectiveness of the proposed facial landmark detection method against state-of-the-art methods.

  14. A measurement-based technique for incipient anomaly detection

    KAUST Repository

    Harrou, Fouzi

    2016-06-13

    Fault detection is essential for safe operation of various engineering systems. Principal component analysis (PCA) has been widely used in monitoring highly correlated process variables. Conventional PCA-based methods, nevertheless, often fail to detect small or incipient faults. In this paper, we develop new PCA-based monitoring charts, combining PCA with multivariate memory control charts, such as the multivariate cumulative sum (MCUSUM) and multivariate exponentially weighted moving average (MEWMA) monitoring schemes. The multivariate control charts with memory are sensitive to small and moderate faults in the process mean, which significantly improves the performance of PCA methods and widen their applicability in practice. Using simulated data, we demonstrate that the proposed PCA-based MEWMA and MCUSUM control charts are more effective in detecting small shifts in the mean of the multivariate process variables, and outperform the conventional PCA-based monitoring charts. © 2015 IEEE.

  15. Stresses In A Cylinder Welded With Mismatch

    Science.gov (United States)

    Min, J. B.; Spanyer, K. L.; Brunair, R. M.

    1993-01-01

    NASA technical memorandum presents parametric study of additional stresses introduced into cylindrical pressure vessel that is round except for radial mismatch in longitudinal butt weld in sidewall. Prompted by concern over fatigue caused by cyclic stresses in longitudinally welded cylindrical titanium inlet of high-pressure turbopump in main engine of Space Shuttle. Results applicable to any round cylindrical pressure vessel characterized by parameters, and conform to simplifying assumptions, used in analysis.

  16. Target Detection Based on EBPSK Satellite Passive Radar

    Directory of Open Access Journals (Sweden)

    Lu Zeyuan

    2015-05-01

    Full Text Available Passive radar is a topic anti stealth technology with simple structure, and low cost. Radiation source model, signal transmission model, and target detection are the key points of passive radar technology research. The paper analyzes the characteristics of EBPSK signal modulation and target detection method aspect of spaceborne radiant source. By comparison with other satellite navigation and positioning system, the characteristics of EBPSK satellite passive radar system are analyzed. It is proved that the maximum detection range of EBPSK satellite signal can satisfy the needs of the proposed model. In the passive radar model, sparse representation is used to achieve high resolution DOA detection. The comparison with the real target track by simulation demonstrates that effective detection of airborne target using EBPSK satellite passive radar system based on sparse representation is efficient.

  17. Dim target detection method based on salient graph fusion

    Science.gov (United States)

    Hu, Ruo-lan; Shen, Yi-yan; Jiang, Jun

    2018-02-01

    Dim target detection is one key problem in digital image processing field. With development of multi-spectrum imaging sensor, it becomes a trend to improve the performance of dim target detection by fusing the information from different spectral images. In this paper, one dim target detection method based on salient graph fusion was proposed. In the method, Gabor filter with multi-direction and contrast filter with multi-scale were combined to construct salient graph from digital image. And then, the maximum salience fusion strategy was designed to fuse the salient graph from different spectral images. Top-hat filter was used to detect dim target from the fusion salient graph. Experimental results show that proposal method improved the probability of target detection and reduced the probability of false alarm on clutter background images.

  18. Edge detection based on computational ghost imaging with structured illuminations

    Science.gov (United States)

    Yuan, Sheng; Xiang, Dong; Liu, Xuemei; Zhou, Xin; Bing, Pibin

    2018-03-01

    Edge detection is one of the most important tools to recognize the features of an object. In this paper, we propose an optical edge detection method based on computational ghost imaging (CGI) with structured illuminations which are generated by an interference system. The structured intensity patterns are designed to make the edge of an object be directly imaged from detected data in CGI. This edge detection method can extract the boundaries for both binary and grayscale objects in any direction at one time. We also numerically test the influence of distance deviations in the interference system on edge extraction, i.e., the tolerance of the optical edge detection system to distance deviation. Hopefully, it may provide a guideline for scholars to build an experimental system.

  19. Research on Daily Objects Detection Based on Deep Neural Network

    Science.gov (United States)

    Ding, Sheng; Zhao, Kun

    2018-03-01

    With the rapid development of deep learning, great breakthroughs have been made in the field of object detection. In this article, the deep learning algorithm is applied to the detection of daily objects, and some progress has been made in this direction. Compared with traditional object detection methods, the daily objects detection method based on deep learning is faster and more accurate. The main research work of this article: 1. collect a small data set of daily objects; 2. in the TensorFlow framework to build different models of object detection, and use this data set training model; 3. the training process and effect of the model are improved by fine-tuning the model parameters.

  20. Automated detection and classification for craters based on geometric matching

    Science.gov (United States)

    Chen, Jian-qing; Cui, Ping-yuan; Cui, Hui-tao

    2011-08-01

    Crater detection and classification are critical elements for planetary mission preparations and landing site selection. This paper presents a methodology for the automated detection and matching of craters on images of planetary surface such as Moon, Mars and asteroids. For craters usually are bowl shaped depression, craters can be figured as circles or circular arc during landing phase. Based on the hypothesis that detected crater edges is related to craters in a template by translation, rotation and scaling, the proposed matching method use circles to fitting craters edge, and align circular arc edges from the image of the target body with circular features contained in a model. The approach includes edge detection, edge grouping, reference point detection and geometric circle model matching. Finally we simulate planetary surface to test the reasonableness and effectiveness of the proposed method.

  1. Wavelet Packet based Detection of Surface Faults on Compact Discs

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob; Wickerhauser, Mladen Victor

    2006-01-01

    In this paper the detection of faults on the surface of a compact disc is addressed. Surface faults like scratches and fingerprints disturb the on-line measurement of the pick-up position relative to the track. This is critical since the pick-up is focused on and tracked at the information track...... based on these measurements. A precise detection of the surface fault is a prerequisite to a correct handling of the faults in order to protect the pick-up of the compact disc player from audible track losses. The actual fault handling which is addressed in other publications can be carried out...... by the use of dedicated filters adapted to remove the faults from the measurements. In this paper detection using wavelet packet filters is demonstrated. The filters are designed using the joint best basis method. Detection using these filters shows a distinct improvement compared to detection using ordinary...

  2. Thermodynamic characterization of tandem mismatches found in naturally occurring RNA

    Science.gov (United States)

    Christiansen, Martha E.; Znosko, Brent M.

    2009-01-01

    Although all sequence symmetric tandem mismatches and some sequence asymmetric tandem mismatches have been thermodynamically characterized and a model has been proposed to predict the stability of previously unmeasured sequence asymmetric tandem mismatches [Christiansen,M.E. and Znosko,B.M. (2008) Biochemistry, 47, 4329–4336], experimental thermodynamic data for frequently occurring tandem mismatches is lacking. Since experimental data is preferred over a predictive model, the thermodynamic parameters for 25 frequently occurring tandem mismatches were determined. These new experimental values, on average, are 1.0 kcal/mol different from the values predicted for these mismatches using the previous model. The data for the sequence asymmetric tandem mismatches reported here were then combined with the data for 72 sequence asymmetric tandem mismatches that were published previously, and the parameters used to predict the thermodynamics of previously unmeasured sequence asymmetric tandem mismatches were updated. The average absolute difference between the measured values and the values predicted using these updated parameters is 0.5 kcal/mol. This updated model improves the prediction for tandem mismatches that were predicted rather poorly by the previous model. This new experimental data and updated predictive model allow for more accurate calculations of the free energy of RNA duplexes containing tandem mismatches, and, furthermore, should allow for improved prediction of secondary structure from sequence. PMID:19509311

  3. Eukaryotic Mismatch Repair in Relation to DNA Replication

    Science.gov (United States)

    Erie, Dorothy A.

    2017-01-01

    Three processes act in series to accurately replicate the eukaryotic nuclear genome. The major replicative DNA polymerases strongly prevent mismatch formation, occasional mismatches that do form are proofread during replication, and rare mismatches that escape proofreading are corrected by mismatch repair (MMR). This review focuses on MMR in light of increasing knowledge about nuclear DNA replication enzymology and the rate and specificity with which mismatches are generated during leading- and lagging-strand replication. We consider differences in MMR efficiency in relation to mismatch recognition, signaling to direct MMR to the nascent strand, mismatch removal, and the timing of MMR. These studies are refining our understanding of relationships between generating and repairing replication errors to achieve accurate replication of both DNA strands of the nuclear genome. PMID:26436461

  4. Arduino-based noise robust online heart-rate detection.

    Science.gov (United States)

    Das, Sangita; Pal, Saurabh; Mitra, Madhuchhanda

    2017-04-01

    This paper introduces a noise robust real time heart rate detection system from electrocardiogram (ECG) data. An online data acquisition system is developed to collect ECG signals from human subjects. Heart rate is detected using window-based autocorrelation peak localisation technique. A low-cost Arduino UNO board is used to implement the complete automated process. The performance of the system is compared with PC-based heart rate detection technique. Accuracy of the system is validated through simulated noisy ECG data with various levels of signal to noise ratio (SNR). The mean percentage error of detected heart rate is found to be 0.72% for the noisy database with five different noise levels.

  5. Stratification-Based Outlier Detection over the Deep Web.

    Science.gov (United States)

    Xian, Xuefeng; Zhao, Pengpeng; Sheng, Victor S; Fang, Ligang; Gu, Caidong; Yang, Yuanfeng; Cui, Zhiming

    2016-01-01

    For many applications, finding rare instances or outliers can be more interesting than finding common patterns. Existing work in outlier detection never considers the context of deep web. In this paper, we argue that, for many scenarios, it is more meaningful to detect outliers over deep web. In the context of deep web, users must submit queries through a query interface to retrieve corresponding data. Therefore, traditional data mining methods cannot be directly applied. The primary contribution of this paper is to develop a new data mining method for outlier detection over deep web. In our approach, the query space of a deep web data source is stratified based on a pilot sample. Neighborhood sampling and uncertainty sampling are developed in this paper with the goal of improving recall and precision based on stratification. Finally, a careful performance evaluation of our algorithm confirms that our approach can effectively detect outliers in deep web.

  6. A UAV-BASED ROE DEER FAWN DETECTION SYSTEM

    Directory of Open Access Journals (Sweden)

    M. Israel

    2012-09-01

    Full Text Available This paper presents a UAV based remote sensing system for the detection of fawns in the meadows. There is a high demand because during pasture mowing many wild animals, especially roe deer fawns are killed by mowing machines. The system was tested in several real situations especially with differing weather and iluminating conditions. Its primary sensor is a lightweight thermal infrared camera. The images are captured onboard of the flight system and also transmitted as analog video stream to the ground station, where the user can follow the camera live stream on a monitor for manual animal detection. Beside a high detection rate a fast workflow is another very important objective for this application. Therefore a waypoint planning software was developed that accelerates the workflow. At adequate illuminating and weather conditions the presented UAV-based fawn detection via thermal imaging is a comfortable, fast and reliable method.

  7. a Uav-Based ROE Deer Fawn Detection System

    Science.gov (United States)

    Israel, M.

    2011-09-01

    This paper presents a UAV based remote sensing system for the detection of fawns in the meadows. There is a high demand because during pasture mowing many wild animals, especially roe deer fawns are killed by mowing machines. The system was tested in several real situations especially with differing weather and iluminating conditions. Its primary sensor is a lightweight thermal infrared camera. The images are captured onboard of the flight system and also transmitted as analog video stream to the ground station, where the user can follow the camera live stream on a monitor for manual animal detection. Beside a high detection rate a fast workflow is another very important objective for this application. Therefore a waypoint planning software was developed that accelerates the workflow. At adequate illuminating and weather conditions the presented UAV-based fawn detection via thermal imaging is a comfortable, fast and reliable method.

  8. The Unknown Computer Viruses Detection Based on Similarity

    Science.gov (United States)

    Liu, Zhongda; Nakaya, Naoshi; Koui, Yuuji

    New computer viruses are continually being generated and they cause damage all over the world. In general, current anti-virus software detects viruses by matching a pattern based on the signature; thus, unknown viruses without any signature cannot be detected. Although there are some static analysis technologies that do not depend on signatures, virus writers often use code obfuscation techniques, which make it difficult to execute a code analysis. As is generally known, unknown viruses and known viruses share a common feature. In this paper we propose a new static analysis technology that can circumvent code obfuscation to extract the common feature and detect unknown viruses based on similarity. The results of evaluation experiments demonstrated that this technique is able to detect unknown viruses without false positives.

  9. Enhancing Community Detection By Affinity-based Edge Weighting Scheme

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Andy [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sanders, Geoffrey [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Henson, Van [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vassilevski, Panayot [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-10-05

    Community detection refers to an important graph analytics problem of finding a set of densely-connected subgraphs in a graph and has gained a great deal of interest recently. The performance of current community detection algorithms is limited by an inherent constraint of unweighted graphs that offer very little information on their internal community structures. In this paper, we propose a new scheme to address this issue that weights the edges in a given graph based on recently proposed vertex affinity. The vertex affinity quantifies the proximity between two vertices in terms of their clustering strength, and therefore, it is ideal for graph analytics applications such as community detection. We also demonstrate that the affinity-based edge weighting scheme can improve the performance of community detection algorithms significantly.

  10. Mutation Rates, Spectra, and Genome-Wide Distribution of Spontaneous Mutations in Mismatch Repair Deficient Yeast

    Science.gov (United States)

    Lang, Gregory I.; Parsons, Lance; Gammie, Alison E.

    2013-01-01

    DNA mismatch repair is a highly conserved DNA repair pathway. In humans, germline mutations in hMSH2 or hMLH1, key components of mismatch repair, have been associated with Lynch syndrome, a leading cause of inherited cancer mortality. Current estimates of the mutation rate and the mutational spectra in mismatch repair defective cells are primarily limited to a small number of individual reporter loci. Here we use the yeast Saccharomyces cerevisiae to generate a genome-wide view of the rates, spectra, and distribution of mutation in the absence of mismatch repair. We performed mutation accumulation assays and next generation sequencing on 19 strains, including 16 msh2 missense variants implicated in Lynch cancer syndrome. The mutation rate for DNA mismatch repair null strains was approximately 1 mutation per genome per generation, 225-fold greater than the wild-type rate. The mutations were distributed randomly throughout the genome, independent of replication timing. The mutation spectra included insertions/deletions at homopolymeric runs (87.7%) and at larger microsatellites (5.9%), as well as transitions (4.5%) and transversions (1.9%). Additionally, repeat regions with proximal repeats are more likely to be mutated. A bias toward deletions at homopolymers and insertions at (AT)n microsatellites suggests a different mechanism for mismatch generation at these sites. Interestingly, 5% of the single base pair substitutions might represent double-slippage events that occurred at the junction of immediately adjacent repeats, resulting in a shift in the repeat boundary. These data suggest a closer scrutiny of tumor suppressors with homopolymeric runs with proximal repeats as the potential drivers of oncogenesis in mismatch repair defective cells. PMID:23821616

  11. Lattice mismatch modeling of aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Dongwon; Roy, Shibayan; Watkins, Thomas R.; Shyam, Amit

    2017-10-01

    We present a theoretical framework to accurately predict the lattice mismatch between the fcc matrix and precipitates in the multi-component aluminum alloys as a function of temperature and composition. We use a computational thermodynamic approach to model the lattice parameters of the multi-component fcc solid solution and θ'-Al2Cu precipitate phase. Better agreement between the predicted lattice parameters of fcc aluminum in five commercial alloys (206, 319, 356, A356, and A356 + 0.5Cu) and experimental data from the synchrotron X-ray diffraction (SXD) has been obtained when simulating supersaturated rather than equilibrium solid solutions. We use the thermal expansion coefficient of thermodynamically stable θ-Al2Cu to describe temperature-dependent lattice parameters of meta-stable θ' and to show good agreement with the SXD data. Both coherent and semi-coherent interface mismatches between the fcc aluminum matrix and θ' in Al-Cu alloys are presented as a function of temperature. Our calculation results show that the concentration of solute atoms, particularly Cu, in the matrix greatly affects the lattice mismatch

  12. Pipeline Processing with an Iterative, Context-Based Detection Model

    Science.gov (United States)

    2016-01-22

    unlimited. 59 optimum choice for steering vectors is the adaptive beamformer weighting [ Capon et al ., 1967] also known as the minimum variance...AFRL-RV-PS- AFRL-RV-PS- TR-2016-0080 TR-2016-0080 PIPELINE PROCESSING WITH AN ITERATIVE, CONTEXT-BASED DETECTION MODEL T. Kværna, et al ...conditions, the capability to detect events down to magnitude 2.0 [Gibbons et al ., 2011]. Figure 3. Location of the SPITS array in relation to Novaya

  13. An Automated Energy Detection Algorithm Based on Consecutive Mean Excision

    Science.gov (United States)

    2018-01-01

    ARL-TR-8268 ● JAN 2018 US Army Research Laboratory An Automated Energy Detection Algorithm Based on Consecutive Mean Excision...not return it to the originator. ARL-TR-8268 ● JAN 2018 US Army Research Laboratory An Automated Energy Detection Algorithm...2018 2. REPORT TYPE Technical Report 3. DATES COVERED (From - To) 1 October 2016–30 September 2017 4. TITLE AND SUBTITLE An Automated Energy

  14. Flow-based Brute-force Attack Detection

    OpenAIRE

    Drašar, Martin; Vykopal, Jan; Winter, Philipp

    2013-01-01

    Brute-force attacks are a prevalent phenomenon that is getting harderto successfully detect on a network level due to increasing volume and en-cryption of network traffic and growing ubiquity of high-speed networks.Although the research in this field advanced considerably, there still remainclasses of attacks that are undetectable. In this chapter, we present sev-eral methods for the detection of brute-force attacks based on the analysisof network flows. We discuss their strengths and shortco...

  15. Computer-vision-based car logotype detection and recognition

    OpenAIRE

    Tomažič, Gašper

    2015-01-01

    This thesis addresses the problem of image-based logotype detection and recognition. A new algorithm for logotype detection in images of cars is proposed. In the first stage, the algorithm localizes all maximally-stable extremal regions as candidates of logotype parts. In the next stage, the regions are combined to create logotype candidates, which are encoded by histograms of gradients. A random forest classifier is then used to verify the candidate regions as being logotypes or not and simu...

  16. Fiber-Optic Based Compact Gas Leak Detection System

    Science.gov (United States)

    deGroot, Wim A.

    1995-01-01

    A propellant leak detection system based on Raman scattering principles is introduced. The proposed system is flexible and versatile as the result of the use of optical fibers. It is shown that multiple species can be monitored simultaneously. In this paper oxygen, nitrogen, carbon monoxide, and hydrogen are detected and monitored. The current detection sensitivity for both hydrogen and carbon monoxide is 1% partial pressure at ambient conditions. The sensitivity for oxygen and nitrogen is 0.5% partial pressure. The response time to changes in species concentration is three minutes. This system can be used to monitor multiple species at several locations.

  17. Statistical Outlier Detection for Jury Based Grading Systems

    DEFF Research Database (Denmark)

    Thompson, Mary Kathryn; Clemmensen, Line Katrine Harder; Rosas, Harvey

    2013-01-01

    This paper presents an algorithm that was developed to identify statistical outliers from the scores of grading jury members in a large project-based first year design course. The background and requirements for the outlier detection system are presented. The outlier detection algorithm...... and the follow-up procedures for score validation and appeals are described in detail. Finally, the impact of various elements of the outlier detection algorithm, their interactions, and the sensitivity of their numerical values are investigated. It is shown that the difference in the mean score produced...

  18. Gold nanoparticle-based microfluidic sensor for mercury detection

    DEFF Research Database (Denmark)

    Lafleur, Josiane P.; Jensen, Thomas Glasdam; Kutter, Jörg Peter

    2011-01-01

    The contamination of natural resources by human activity can have severe socio-economical impacts. Conventional methods of environmental analysis can be significantly improved by the development of portable microscale technologies for remote/field sensing. A gold nanoparticle-based lab-on-a-chip ......-on-a-chip device was developed for the rapid, in-field detection and quantification of mercury in aquatic environments. Rhodamine 6G functionalized gold nanoparticles allowed the on-chip fluorescence detection of mercury in aqueous samples with a limit of detection of 7 nM....

  19. Mismatch analysis of humeral nailing. Antegrade versus retrograde insertion

    International Nuclear Information System (INIS)

    Mahaisavariya, B.; Jiamwatthanachai, P.; Aroonjarattham, P.; Aroonjarattham, K.; Wongcumchang, M.; Sitthiseripratip, K.

    2011-01-01

    Closed humeral nailing is now considered an alternative treatment for humeral-shaft fracture. The nail can be inserted with either the antegrade or retrograde method. We investigated and compared the problem of geometric mismatch of the humeral nail to the humerus between the two methods of insertion. The study was performed using virtual simulation based on computed tomography (CT) data of 76 Thai cadaveric humeri and the commonly used Russell-Taylor humeral nail 8 mm in diameter and 220 mm long. Mismatch of the nail to the intact humerus was analyzed and compared between the antegrade and retrograde nailing approaches. The results showed: the diameter of the medullary canal averaged 7.9-13.8 mm; the minimal reaming diameter to accommodate virtual nail insertion averaged 8.8-14.8 mm for the antegrade and 8.8-29.3 mm for the retrograde approach; the minimal reaming thickness of the inner cortex averaged 0.1-1.5 mm for the antegrade and 0.1-9.9 mm for the retrograde approach; the percentages of cortical bone removed prior to nail insertion were 3.8-107.1% and 3.8-1,287.6% for the antegrade and retrograde approaches, respectively; the eccentricity of the nail-medullary canal center were 0.4-3.4 and 0.4-10.6 mm for the antegrade and retrograde approaches, respectively. Less mismatching occurred with antegrade nailing than with the retrograde approach. Retrograde nailing requires excessive reaming at the distal part of the humerus to accommodate nail insertion. This may create bone weakness and the risk of supracondylar fracture. (author)

  20. Tactile sensor of hardness recognition based on magnetic anomaly detection

    Science.gov (United States)

    Xue, Lingyun; Zhang, Dongfang; Chen, Qingguang; Rao, Huanle; Xu, Ping

    2018-03-01

    Hardness, as one kind of tactile sensing, plays an important role in the field of intelligent robot application such as gripping, agricultural harvesting, prosthetic hand and so on. Recently, with the rapid development of magnetic field sensing technology with high performance, a number of magnetic sensors have been developed for intelligent application. The tunnel Magnetoresistance(TMR) based on magnetoresistance principal works as the sensitive element to detect the magnetic field and it has proven its excellent ability of weak magnetic detection. In the paper, a new method based on magnetic anomaly detection was proposed to detect the hardness in the tactile way. The sensor is composed of elastic body, ferrous probe, TMR element, permanent magnet. When the elastic body embedded with ferrous probe touches the object under the certain size of force, deformation of elastic body will produce. Correspondingly, the ferrous probe will be forced to displace and the background magnetic field will be distorted. The distorted magnetic field was detected by TMR elements and the output signal at different time can be sampled. The slope of magnetic signal with the sampling time is different for object with different hardness. The result indicated that the magnetic anomaly sensor can recognize the hardness rapidly within 150ms after the tactile moment. The hardness sensor based on magnetic anomaly detection principal proposed in the paper has the advantages of simple structure, low cost, rapid response and it has shown great application potential in the field of intelligent robot.

  1. Deceiving entropy-based DoS detection

    Science.gov (United States)

    Özçelik, Ä.°lker; Brooks, Richard R.

    2014-06-01

    Denial of Service (DoS) attacks disable network services for legitimate users. A McAfee report shows that eight out of ten Critical Infrastructure Providers (CIPs) surveyed had a significant Distributed DoS (DDoS) attack in 2010.1 Researchers proposed many approaches for detecting these attacks in the past decade. Anomaly based DoS detection is the most common. In this approach, the detector uses statistical features; such as the entropy of incoming packet header fields like source IP addresses or protocol type. It calculates the observed statistical feature and triggers an alarm if an extreme deviation occurs. However, intrusion detection systems (IDS) using entropy based detection can be fooled by spoofing. An attacker can sniff the network to collect header field data of network packets coming from distributed nodes on the Internet and fuses them to calculate the entropy of normal background traffic. Then s/he can spoof attack packets to keep the entropy value in the expected range during the attack. In this study, we present a proof of concept entropy spoofing attack that deceives entropy based detection approaches. Our preliminary results show that spoofing attacks cause significant detection performance degradation.

  2. Vision-Based People Detection System for Heavy Machine Applications

    Directory of Open Access Journals (Sweden)

    Vincent Fremont

    2016-01-01

    Full Text Available This paper presents a vision-based people detection system for improving safety in heavy machines. We propose a perception system composed of a monocular fisheye camera and a LiDAR. Fisheye cameras have the advantage of a wide field-of-view, but the strong distortions that they create must be handled at the detection stage. Since people detection in fisheye images has not been well studied, we focus on investigating and quantifying the impact that strong radial distortions have on the appearance of people, and we propose approaches for handling this specificity, adapted from state-of-the-art people detection approaches. These adaptive approaches nevertheless have the drawback of high computational cost and complexity. Consequently, we also present a framework for harnessing the LiDAR modality in order to enhance the detection algorithm for different camera positions. A sequential LiDAR-based fusion architecture is used, which addresses directly the problem of reducing false detections and computational cost in an exclusively vision-based system. A heavy machine dataset was built, and different experiments were carried out to evaluate the performance of the system. The results are promising, in terms of both processing speed and performance.

  3. Vision-Based People Detection System for Heavy Machine Applications.

    Science.gov (United States)

    Fremont, Vincent; Bui, Manh Tuan; Boukerroui, Djamal; Letort, Pierrick

    2016-01-20

    This paper presents a vision-based people detection system for improving safety in heavy machines. We propose a perception system composed of a monocular fisheye camera and a LiDAR. Fisheye cameras have the advantage of a wide field-of-view, but the strong distortions that they create must be handled at the detection stage. Since people detection in fisheye images has not been well studied, we focus on investigating and quantifying the impact that strong radial distortions have on the appearance of people, and we propose approaches for handling this specificity, adapted from state-of-the-art people detection approaches. These adaptive approaches nevertheless have the drawback of high computational cost and complexity. Consequently, we also present a framework for harnessing the LiDAR modality in order to enhance the detection algorithm for different camera positions. A sequential LiDAR-based fusion architecture is used, which addresses directly the problem of reducing false detections and computational cost in an exclusively vision-based system. A heavy machine dataset was built, and different experiments were carried out to evaluate the performance of the system. The results are promising, in terms of both processing speed and performance.

  4. Compressive Sensing-Based Detection With Multimodal Dependent Data

    Science.gov (United States)

    Wimalajeewa, Thakshila; Varshney, Pramod K.

    2018-02-01

    Detection with high dimensional multimodal data is a challenging problem when there are complex inter- and intra- modal dependencies. While several approaches have been proposed for dependent data fusion (e.g., based on copula theory), their advantages come at a high price in terms of computational complexity. In this paper, we treat the detection problem with compressive sensing (CS) where compression at each sensor is achieved via low dimensional random projections. CS has recently been exploited to solve detection problems under various assumptions on the signals of interest, however, its potential for dependent data fusion has not been explored adequately. We exploit the capability of CS to capture statistical properties of uncompressed data in order to compute decision statistics for detection in the compressed domain. First, a Gaussian approximation is employed to perform likelihood ratio (LR) based detection with compressed data. In this approach, inter-modal dependence is captured via a compressed version of the covariance matrix of the concatenated (temporally and spatially) uncompressed data vector. We show that, under certain conditions, this approach with a small number of compressed measurements per node leads to enhanced performance compared to detection with uncompressed data using widely considered suboptimal approaches. Second, we develop a nonparametric approach where a decision statistic based on the second order statistics of uncompressed data is computed in the compressed domain. The second approach is promising over other related nonparametric approaches and the first approach when multimodal data is highly correlated at the expense of slightly increased computational complexity.

  5. Hyperspectral anomaly detection based on stacked denoising autoencoders

    Science.gov (United States)

    Zhao, Chunhui; Li, Xueyuan; Zhu, Haifeng

    2017-10-01

    Hyperspectral anomaly detection (AD) is an important technique of unsupervised target detection and has significance in real situations. Due to the high dimensionality of hyperspectral data, AD will be influenced by noise, nonlinear correlation of band, or other factors that lead to the decline of detection accuracy. To overcome this problem, a method of hyperspectral AD based on stacked denoising autoencoders (AE) (HADSDA) is proposed. Simultaneously, two different feature detection models, spectral feature (SF) and fused feature by clustering (FFC), are constructed to verify the effectiveness of the proposed algorithm. The SF detection model uses the SF of each pixel. The FFC detection model uses a similar set of pixels constructed by clustering and then fuses the set of pixels by the stacked denoising autoencoders algorithm (SDA). The SDA is an algorithm that can automatically learn nonlinear deep features of the image. Compared with other linear or nonlinear feature extraction methods, the detection result of the proposed algorithm is greatly improved. Experiment results show that the proposed algorithm is an excellent feature learning method and can achieve higher detection performance.

  6. Analysis of Vehicle Detection with WSN-Based Ultrasonic Sensors

    Directory of Open Access Journals (Sweden)

    Youngtae Jo

    2014-08-01

    Full Text Available Existing traffic information acquisition systems suffer from high cost and low scalability. To address these problems, the application of wireless sensor networks (WSNs has been studied, as WSN-based systems are highly scalable and have a low cost of installing and replacing the systems. Magnetic, acoustic and accelerometer sensors have been considered for WSN-based traffic surveillance, but the use of ultrasonic sensors has not been studied. The limitations of WSN-based systems make it necessary to employ power saving methods and vehicle detection algorithms with low computational complexity. In this paper, we model and analyze optimal power saving methodologies for an ultrasonic sensor and present a computationally-efficient vehicle detection algorithm using ultrasonic data. The proposed methodologies are implemented and evaluated with a tiny microprocessor on real roads. The evaluation results show that the low computational complexity of our algorithm does not compromise the accuracy of vehicle detection.

  7. DNA methylation detection based on difference of base content

    Science.gov (United States)

    Sato, Shinobu; Ohtsuka, Keiichi; Honda, Satoshi; Sato, Yusuke; Takenaka, Shigeori

    2016-04-01

    Methylation frequently occurs in cytosines of CpG sites to regulate gene expression. The identification of aberrant methylation of certain genes is important for cancer marker analysis. The aim of this study was to determine the methylation frequency in DNA samples of unknown length and/or concentration. Unmethylated cytosine is known to be converted to thymine following bisulfite treatment and subsequent PCR. For this reason, the AT content in DNA increases with an increasing number of methylation sites. In this study, the fluorescein-carrying bis-acridinyl peptide (FKA) molecule was used for the detection of methylation frequency. FKA contains fluorescein and two acridine moieties, which together allow for the determination of the AT content of double-stranded DNA fragments. Methylated and unmethylated human genomes were subjected to bisulfide treatment and subsequent PCR using primers specific for the CFTR, CDH4, DBC1, and NPY genes. The AT content in the resulting PCR products was estimated by FKA, and AT content estimations were found to be in good agreement with those determined by DNA sequencing. This newly developed method may be useful for determining methylation frequencies of many PCR products by measuring the fluorescence in samples excited at two different wavelengths.

  8. State-based Event Detection Optimization for Complex Event Processing

    Directory of Open Access Journals (Sweden)

    Shanglian PENG

    2014-02-01

    Full Text Available Detection of patterns in high speed, large volume of event streams has been an important paradigm in many application areas of Complex Event Processing (CEP including security monitoring, financial markets analysis and health-care monitoring. To assure real-time responsive complex pattern detection over high volume and speed event streams, efficient event detection techniques have to be designed. Unfortunately evaluation of the Nondeterministic Finite Automaton (NFA based event detection model mainly considers single event query and its optimization. In this paper, we propose multiple event queries evaluation on event streams. In particular, we consider scalable multiple event detection model that shares NFA transfer states of different event queries. For each event query, the event query is parse into NFA and states of the NFA are partitioned into different units. With this partition, the same individual state of NFA is run on different processing nodes, providing states sharing and reducing partial matches maintenance. We compare our state-based approach with Stream-based And Shared Event processing (SASE. Our experiments demonstrate that state-based approach outperforms SASE both on CPU time usage and memory consumption.

  9. The detection of bulk explosives using nuclear-based techniques

    Energy Technology Data Exchange (ETDEWEB)

    Morgado, R.E.; Gozani, T.; Seher, C.C.

    1988-01-01

    In 1986 we presented a rationale for the detection of bulk explosives based on nuclear techniques that addressed the requirements of civil aviation security in the airport environment. Since then, efforts have intensified to implement a system based on thermal neutron activation (TNA), with new work developing in fast neutron and energetic photon reactions. In this paper we will describe these techniques and present new results from laboratory and airport testing. Based on preliminary results, we contended in our earlier paper that nuclear-based techniques did provide sufficiently penetrating probes and distinguishable detectable reaction products to achieve the FAA operational goals; new data have supported this contention. The status of nuclear-based techniques for the detection of bulk explosives presently under investigation by the US Federal Aviation Administration (FAA) is reviewed. These include thermal neutron activation (TNA), fast neutron activation (FNA), the associated particle technique, nuclear resonance absorption, and photoneutron activation. The results of comprehensive airport testing of the TNA system performed during 1987-88 are summarized. From a technical point of view, nuclear-based techniques now represent the most comprehensive and feasible approach for meeting the operational criteria of detection, false alarms, and throughput. 9 refs., 5 figs., 2 tabs.

  10. DNA mismatch repair enzymes: genetic defects and autoimmunity.

    Science.gov (United States)

    Muro, Yoshinao; Sugiura, Kazumitsu; Mimori, Tsuneyo; Akiyama, Masashi

    2015-03-10

    DNA mismatch repair (MMR) is one of the several DNA repair pathways conserved from bacteria to humans. The primary function of MMR is to eliminate the mismatch of base-base insertions and deletions that appear as a consequence of DNA polymerase errors at DNA synthesis. The genes encoding the DNA MMR enzymes (MMREs) are highly conserved throughout evolution. In humans, there are two sets of MMREs, corresponding to homologues of the bacterial MutLS systems. The human MutS enzymes consist of MSH2, MSH3 and MSH6, and the human MutL enzymes include MLH1, MLH3, PMS1 and PMS2. Since the beginning of this century, a few reports on autoantibodies to some MMREs have been reported in autoimmune inflammatory myopathy, cancer and hematological disorders. This review charts the functional structures of MMREs, their genetic defects and associated disorders, and autoimmunity to MMREs, including our recent data that was the first to analyze autoantibodies against all seven kinds of MMREs in systemic autoimmune diseases, including idiopathic inflammatory myopathies. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Mismatch repair pathway: molecules, functions, and role in colorectal carcinogenesis.

    Science.gov (United States)

    Sameer, Aga Syed; Nissar, Saniya; Fatima, Kaneez

    2014-07-01

    The microsatellite instability (MSI) pathway is one of the important mutational pathways that play a critical role in colorectal carcinogenesis. About 15% of colorectal cancers (CRCs) are characterized by MSI. MSI tumors usually arise because of a genetic defect in mismatch repair (MMR) genes, one of the main DNA-repairing systems. MMR is a highly conserved biological pathway that plays a key role in maintaining genomic stability by correcting the base-base mismatches and insertion/deletion mispairs generated during DNA replication and recombination. Escherichia coli MutS and MutL and their eukaryotic homologs, MutSα and MutLα, respectively, are key players in MMR-associated genome maintenance. Mutations in at least five pivotal genes of MMR, namely, in those encoding mutS homolog 2 (MSH2), mutL homolog 1 (MLH1), mutS homolog 6 (MSH6), postmeiotic segregation increased 1 (PMS1), and postmeiotic segregation, increased 2 (PMS2) have been found in CRC, highlighting the importance of understanding the basic structure and functions of the essential molecules that make up the MMR system. In this review, we have attempted to focus on this aspect, that is, the role that MMR molecules play in CRC carcinogenesis.

  12. Mismatch repair deficiency does not enhance ENU mutagenesis in the zebrafish germ line.

    NARCIS (Netherlands)

    Feitsma, H.; de Bruijn, E.; van de Belt, J.; Nijman, I.J.; Cuppen, E.

    2008-01-01

    S(N)1-type alkylating agents such as N-ethyl-N-nitrosourea (ENU) are very potent mutagens. They act by transferring their alkyl group to DNA bases, which, upon mispairing during replication, can cause single base pair mutations in the next replication cycle. As DNA mismatch repair (MMR) proteins are

  13. Temperament and Mood Detection Using Case-Based Reasoning

    OpenAIRE

    Adebayo Kolawole John; Adekoya Adewale M.; Ekwonna Chinnasa

    2014-01-01

    Case-Based Reasoning (CBR) is a branch of AI that is employed to solving problems which emphasizes the use of previous solutions in solving similar new problems. This work presents TAMDS, a Temperament and Mood Detection system which employs Case-Based Reasoning technique. The proposed system is adapted to the field of psychology to help psychologists solve part of the problems in their complex domain. We have designed TAMDS to detect temperament and moods of individuals. A major aim of our s...

  14. VoIP attacks detection engine based on neural network

    Science.gov (United States)

    Safarik, Jakub; Slachta, Jiri

    2015-05-01

    The security is crucial for any system nowadays, especially communications. One of the most successful protocols in the field of communication over IP networks is Session Initiation Protocol. It is an open-source project used by different kinds of applications, both open-source and proprietary. High penetration and text-based principle made SIP number one target in IP telephony infrastructure, so security of SIP server is essential. To keep up with hackers and to detect potential malicious attacks, security administrator needs to monitor and evaluate SIP traffic in the network. But monitoring and following evaluation could easily overwhelm the security administrator in networks, typically in networks with a number of SIP servers, users and logically or geographically separated networks. The proposed solution lies in automatic attack detection systems. The article covers detection of VoIP attacks through a distributed network of nodes. Then the gathered data analyze aggregation server with artificial neural network. Artificial neural network means multilayer perceptron network trained with a set of collected attacks. Attack data could also be preprocessed and verified with a self-organizing map. The source data is detected by distributed network of detection nodes. Each node contains a honeypot application and traffic monitoring mechanism. Aggregation of data from each node creates an input for neural networks. The automatic classification on a centralized server with low false positive detection reduce the cost of attack detection resources. The detection system uses modular design for easy deployment in final infrastructure. The centralized server collects and process detected traffic. It also maintains all detection nodes.

  15. Genome instability in mismatch repair and its role on radiation-induced cancer

    Energy Technology Data Exchange (ETDEWEB)

    Munakata, Nobuo; Morohoshi, Fumiko [National Cancer Center, Tokyo (Japan). Research Inst

    2000-02-01

    Studies on mismatch repair mechanism have been progressed using Caenorhabditis elegans, a nematode since its genetic analysis is comparatively easy. In this study, homologue gene for mismatch repairing of nematoda were investigated and 3 kinds of homologue genes of mut S; msh G, msh Z and msh F and two kinds of mut L homologue genes were identified. Based on these genes, each cDNA was isolated aiming to determine the sequence and clarify the phylogenetic relationship. Either of msh G, msh Z and msh F is present in the cDNA library, suggesting that these genes might be expressed in every stage of development. Northern analysis was made using the RNA fractions extracted from nematoda at various stages of development as a probe for cDNA of msh G and msh Z, and each corresponding bands were detected for the imago and the matured larva, but not so distinct for the larva and embryo, suggesting that both genes would be regulated in the transcription step at each development stage. Then, resistant larva in which Tcl transposon is activated was cultured and its DNA was extracted to use as a template DNA. Thus, Tcl transposon inserted strains for three of 8 repair related genes were obtained. The passages of these strains were kept comparatively stable. However, the sensitivities to ionizing radiation, ultraviolet light and alkyl agents of these inserted strains were not so different from the control. PCR reaction revealed that DNA fragments of which Tcl was excluded were produced in a certain stage of development. This suggest in vivo exclusion of Tcl in somatic cells. (M.N.)

  16. A Frequency-Based Approach to Intrusion Detection

    Directory of Open Access Journals (Sweden)

    Mian Zhou

    2004-06-01

    Full Text Available Research on network security and intrusion detection strategies presents many challenging issues to both theoreticians and practitioners. Hackers apply an array of intrusion and exploit techniques to cause disruption of normal system operations, but on the defense, firewalls and intrusion detection systems (IDS are typically only effective in defending known intrusion types using their signatures, and are far less than mature when faced with novel attacks. In this paper, we adapt the frequency analysis techniques such as the Discrete Fourier Transform (DFT used in signal processing to the design of intrusion detection algorithms. We demonstrate the effectiveness of the frequency-based detection strategy by running synthetic network intrusion data in simulated networks using the OPNET software. The simulation results indicate that the proposed intrusion detection strategy is effective in detecting anomalous traffic data that exhibit patterns over time, which include several types of DOS and probe attacks. The significance of this new strategy is that it does not depend on the prior knowledge of attack signatures, thus it has the potential to be a useful supplement to existing signature-based IDS and firewalls.

  17. Analysis of Android Device-Based Solutions for Fall Detection.

    Science.gov (United States)

    Casilari, Eduardo; Luque, Rafael; Morón, María-José

    2015-07-23

    Falls are a major cause of health and psychological problems as well as hospitalization costs among older adults. Thus, the investigation on automatic Fall Detection Systems (FDSs) has received special attention from the research community during the last decade. In this area, the widespread popularity, decreasing price, computing capabilities, built-in sensors and multiplicity of wireless interfaces of Android-based devices (especially smartphones) have fostered the adoption of this technology to deploy wearable and inexpensive architectures for fall detection. This paper presents a critical and thorough analysis of those existing fall detection systems that are based on Android devices. The review systematically classifies and compares the proposals of the literature taking into account different criteria such as the system architecture, the employed sensors, the detection algorithm or the response in case of a fall alarms. The study emphasizes the analysis of the evaluation methods that are employed to assess the effectiveness of the detection process. The review reveals the complete lack of a reference framework to validate and compare the proposals. In addition, the study also shows that most research works do not evaluate the actual applicability of the Android devices (with limited battery and computing resources) to fall detection solutions.

  18. Semantic-based technique for thai documents plagiarism detection

    Directory of Open Access Journals (Sweden)

    Sorawat Prapanitisatian

    2014-03-01

    Full Text Available Plagiarism is the act of taking another person's writing or idea without referring to the source of information. This is one of major problems in educational institutes. There is a number of plagiarism detection software available on the Internet. However, a few numbers of them works. Typically, they use a simple method for plagiarism detection e.g. string matching. The main weakness of this method is it cannot detect the plagiarism when the author replaces some words using synonyms. As such, this paper presents a new technique for a semantic-based plagiarism detection using Semantic Role Labeling (SRL and term weighting. SRL is deployed in order to calculate the semantic-based similarity. The main different from the existing framework is terms in a sentence are weighted dynamically depending on their roles in the sentence e.g. subject, verb or object. This technique enhances the plagiarism detection mechanism more efficiently than existing system although positions of terms in a sentence are reordered. The experimental results show that the proposed method can detect the plagiarism document more effective than the existing methods, Anti-kobpae, Turnit-in and Traditional Semantic Role Labeling.

  19. An Effective Conversation-Based Botnet Detection Method

    Directory of Open Access Journals (Sweden)

    Ruidong Chen

    2017-01-01

    Full Text Available A botnet is one of the most grievous threats to network security since it can evolve into many attacks, such as Denial-of-Service (DoS, spam, and phishing. However, current detection methods are inefficient to identify unknown botnet. The high-speed network environment makes botnet detection more difficult. To solve these problems, we improve the progress of packet processing technologies such as New Application Programming Interface (NAPI and zero copy and propose an efficient quasi-real-time intrusion detection system. Our work detects botnet using supervised machine learning approach under the high-speed network environment. Our contributions are summarized as follows: (1 Build a detection framework using PF_RING for sniffing and processing network traces to extract flow features dynamically. (2 Use random forest model to extract promising conversation features. (3 Analyze the performance of different classification algorithms. The proposed method is demonstrated by well-known CTU13 dataset and nonmalicious applications. The experimental results show our conversation-based detection approach can identify botnet with higher accuracy and lower false positive rate than flow-based approach.

  20. Two-year-olds' sensitivity to subphonemic mismatch during online spoken word recognition.

    Science.gov (United States)

    Paquette-Smith, Melissa; Fecher, Natalie; Johnson, Elizabeth K

    2016-11-01

    Sensitivity to noncontrastive subphonemic detail plays an important role in adult speech processing, but little is known about children's use of this information during online word recognition. In two eye-tracking experiments, we investigate 2-year-olds' sensitivity to a specific type of subphonemic detail: coarticulatory mismatch. In Experiment 1, toddlers viewed images of familiar objects (e.g., a boat and a book) while hearing labels containing appropriate or inappropriate coarticulation. Inappropriate coarticulation was created by cross-splicing the coda of the target word onto the onset of another word that shared the same onset and nucleus (e.g., to create boat, the final consonant of boat was cross-spliced onto the initial CV of bone). We tested 24-month-olds and 29-month-olds in this paradigm. Both age groups behaved similarly, readily detecting the inappropriate coarticulation (i.e., showing better recognition of identity-spliced than cross-spliced items). In Experiment 2, we asked how children's sensitivity to subphonemic mismatch compared to their sensitivity to phonemic mismatch. Twenty-nine-month-olds were presented with targets that contained either a phonemic (e.g., the final consonant of boat was spliced onto the initial CV of bait) or a subphonemic mismatch (e.g., the final consonant of boat was spliced onto the initial CV of bone). Here, the subphonemic (coarticulatory) mismatch was not nearly as disruptive to children's word recognition as a phonemic mismatch. Taken together, our findings support the view that 2-year-olds, like adults, use subphonemic information to optimize online word recognition.

  1. Accounting for detectability in fish distribution models: an approach based on time-to-first-detection

    Directory of Open Access Journals (Sweden)

    Mário Ferreira

    2015-12-01

    Full Text Available Imperfect detection (i.e., failure to detect a species when the species is present is increasingly recognized as an important source of uncertainty and bias in species distribution modeling. Although methods have been developed to solve this problem by explicitly incorporating variation in detectability in the modeling procedure, their use in freshwater systems remains limited. This is probably because most methods imply repeated sampling (≥ 2 of each location within a short time frame, which may be impractical or too expensive in most studies. Here we explore a novel approach to control for detectability based on the time-to-first-detection, which requires only a single sampling occasion and so may find more general applicability in freshwaters. The approach uses a Bayesian framework to combine conventional occupancy modeling with techniques borrowed from parametric survival analysis, jointly modeling factors affecting the probability of occupancy and the time required to detect a species. To illustrate the method, we modeled large scale factors (elevation, stream order and precipitation affecting the distribution of six fish species in a catchment located in north-eastern Portugal, while accounting for factors potentially affecting detectability at sampling points (stream depth and width. Species detectability was most influenced by depth and to lesser extent by stream width and tended to increase over time for most species. Occupancy was consistently affected by stream order, elevation and annual precipitation. These species presented a widespread distribution with higher uncertainty in tributaries and upper stream reaches. This approach can be used to estimate sampling efficiency and provide a practical framework to incorporate variations in the detection rate in fish distribution models.

  2. A stereo vision-based obstacle detection system in vehicles

    Science.gov (United States)

    Huh, Kunsoo; Park, Jaehak; Hwang, Junyeon; Hong, Daegun

    2008-02-01

    Obstacle detection is a crucial issue for driver assistance systems as well as for autonomous vehicle guidance function and it has to be performed with high reliability to avoid any potential collision with the front vehicle. The vision-based obstacle detection systems are regarded promising for this purpose because they require little infrastructure on a highway. However, the feasibility of these systems in passenger car requires accurate and robust sensing performance. In this paper, an obstacle detection system using stereo vision sensors is developed. This system utilizes feature matching, epipoplar constraint and feature aggregation in order to robustly detect the initial corresponding pairs. After the initial detection, the system executes the tracking algorithm for the obstacles. The proposed system can detect a front obstacle, a leading vehicle and a vehicle cutting into the lane. Then, the position parameters of the obstacles and leading vehicles can be obtained. The proposed obstacle detection system is implemented on a passenger car and its performance is verified experimentally.

  3. Ground-based detection of G star superflares with NGTS

    Science.gov (United States)

    Jackman, James A. G.; Wheatley, Peter J.; Pugh, Chloe E.; Gänsicke, Boris T.; Gillen, Edward; Broomhall, Anne-Marie; Armstrong, David J.; Burleigh, Matthew R.; Chaushev, Alexander; Eigmüller, Philipp; Erikson, Anders; Goad, Michael R.; Grange, Andrew; Günther, Maximilian N.; Jenkins, James S.; McCormac, James; Raynard, Liam; Thompson, Andrew P. G.; Udry, Stéphane; Walker, Simon; Watson, Christopher A.; West, Richard G.

    2018-04-01

    We present high cadence detections of two superflares from a bright G8 star (V = 11.56) with the Next Generation Transit Survey (NGTS). We improve upon previous superflare detections by resolving the flare rise and peak, allowing us to fit a solar flare inspired model without the need for arbitrary break points between rise and decay. Our data also enables us to identify substructure in the flares. From changing starspot modulation in the NGTS data we detect a stellar rotation period of 59 hours, along with evidence for differential rotation. We combine this rotation period with the observed ROSAT X-ray flux to determine that the star's X-ray activity is saturated. We calculate the flare bolometric energies as 5.4^{+0.8}_{-0.7}× 10^{34}and 2.6^{+0.4}_{-0.3}× 10^{34}erg and compare our detections with G star superflares detected in the Kepler survey. We find our main flare to be one of the largest amplitude superflares detected from a bright G star. With energies more than 100 times greater than the Carrington event, our flare detections demonstrate the role that ground-based instruments such as NGTS can have in assessing the habitability of Earth-like exoplanets, particularly in the era of PLATO.

  4. Colour based fire detection method with temporal intensity variation filtration

    International Nuclear Information System (INIS)

    Trambitckii, K; Musalimov, V; Anding, K; Linß, G

    2015-01-01

    Development of video, computing technologies and computer vision gives a possibility of automatic fire detection on video information. Under that project different algorithms was implemented to find more efficient way of fire detection. In that article colour based fire detection algorithm is described. But it is not enough to use only colour information to detect fire properly. The main reason of this is that in the shooting conditions may be a lot of things having colour similar to fire. A temporary intensity variation of pixels is used to separate them from the fire. These variations are averaged over the series of several frames. This algorithm shows robust work and was realised as a computer program by using of the OpenCV library

  5. Local Community Detection Algorithm Based on Minimal Cluster

    Directory of Open Access Journals (Sweden)

    Yong Zhou

    2016-01-01

    Full Text Available In order to discover the structure of local community more effectively, this paper puts forward a new local community detection algorithm based on minimal cluster. Most of the local community detection algorithms begin from one node. The agglomeration ability of a single node must be less than multiple nodes, so the beginning of the community extension of the algorithm in this paper is no longer from the initial node only but from a node cluster containing this initial node and nodes in the cluster are relatively densely connected with each other. The algorithm mainly includes two phases. First it detects the minimal cluster and then finds the local community extended from the minimal cluster. Experimental results show that the quality of the local community detected by our algorithm is much better than other algorithms no matter in real networks or in simulated networks.

  6. A DFIG Islanding Detection Scheme Based on Reactive Power Infusion

    Science.gov (United States)

    Wang, M.; Liu, C.; He, G. Q.; Li, G. H.; Feng, K. H.; Sun, W. W.

    2017-07-01

    A lot of research has been done on photovoltaic (the “PV”) power system islanding detection in recent years. As a comparison, much less attention has been paid to islanding in wind turbines. Meanwhile, wind turbines can work in islanding conditions for quite a long period, which can be harmful to equipments and cause safety hazards. This paper presents and examines a double fed introduction generation (the “DFIG”) islanding detection scheme based on feedback of reactive power and frequency and uses a trigger signal of reactive power infusion which can be obtained by dividing the voltage total harmonic distortion (the "THD") by the voltage THD of last cycle to avoid the deterioration of power quality. This DFIG islanding detection scheme uses feedback of reactive power current loop to amplify the frequency differences in islanding and normal conditions. Simulation results show that the DFIG islanding detection scheme is effective.

  7. Sequence-dependent cleavage of mismatched DNA by Ban I restriction endonuclease.

    Science.gov (United States)

    Gao, Weimin; Zhu, Dan; Keohavong, Phouthone

    2017-10-01

    Restriction enzymes have previously shown the ability to cleave DNA substrates with mismatched base(s) in recognition sequences; in this study, Ban I endonuclease demonstrated this same ability. Single base substitutions were introduced, and fragments containing various types of unpaired base(s) (heteroduplex fragments) within the Ban I endonuclease recognition sequence, 5'-G|GPyPuCC-3', were generated. Each of the heteroduplex fragments was treated with Ban I endonuclease and analyzed by denaturing gradient gel electrophoresis. Our results showed that heteroduplex fragments containing mismatched bases at either the first or third position of the Ban I recognition sequence or, because of the symmetrical structure of the sequence, the sixth or fourth position on the opposite strand were cleaved by the enzyme. Furthermore, these cleaved fragments contained at least one strand corresponding to the original Ban I recognition sequence. Fragments with mismatches formed by an A (noncanonical, nc) opposite a purine (canonical, ca) or a T (nc) opposite a pyrimidine (ca) were cleaved more efficiently than other types of mismatched bases. These results may help elucidate the mechanisms by which DNA and protein interact during the process of DNA cleavage by Ban I endonuclease. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Engineering nanomaterials-based biosensors for food safety detection.

    Science.gov (United States)

    Lv, Man; Liu, Yang; Geng, Jinhui; Kou, Xiaohong; Xin, Zhihong; Yang, Dayong

    2018-05-30

    Food safety always remains a grand global challenge to human health, especially in developing countries. To solve food safety pertained problems, numerous strategies have been developed to detect biological and chemical contaminants in food. Among these approaches, nanomaterials-based biosensors provide opportunity to realize rapid, sensitive, efficient and portable detection, overcoming the restrictions and limitations of traditional methods such as complicated sample pretreatment, long detection time, and relying on expensive instruments and well-trained personnel. In this review article, we provide a cross-disciplinary perspective to review the progress of nanomaterials-based biosensors for the detection of food contaminants. The review article is organized by the category of food contaminants including pathogens/toxins, heavy metals, pesticides, veterinary drugs and illegal additives. In each category of food contaminant, the biosensing strategies are summarized including optical, colorimetric, fluorescent, electrochemical, and immune- biosensors; the relevant analytes, nanomaterials and biosensors are analyzed comprehensively. Future perspectives and challenges are also discussed briefly. We envision that our review could bridge the gap between the fields of food science and nanotechnology, providing implications for the scientists or engineers in both areas to collaborate and promote the development of nanomaterials-based biosensors for food safety detection. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Ensemble regression model-based anomaly detection for cyber-physical intrusion detection in smart grids

    DEFF Research Database (Denmark)

    Kosek, Anna Magdalena; Gehrke, Oliver

    2016-01-01

    on an ensemble of non-linear artificial neural network DER models which detect and evaluate anomalies in DER operation. The proposed method is validated against measurement data which yields a precision of 0.947 and an accuracy of 0.976. This improves the precision and accuracy of a classic model-based anomaly...

  10. Femoral head retroposition as a potential compensatory mechanism in patients with a severe mismatch between pelvic incidence and lumbar lordosis.

    Science.gov (United States)

    Cheng, Xiaofei; Zhang, Kai; Sun, Xiaojiang; Zhao, Changqing; Li, Hua; Zhao, Jie

    2017-12-01

    Severe mismatch between pelvic incidence (PI) and lumbar lordosis (LL) leads to extra anterior displacement of the gravity line. The objective of this study is to investigate whether femoral head retroposition is a separate compensatory mechanism responsible for the extra anterior displacement. Based on the values of PI and LL, 94 patients were divided into the PI-LL match group (PI-LL ≤ 0°), the mild PI-LL mismatch group (20°> PI-LL >0°), and the severe PI-LL mismatch group (PI-LL ≥ 20°). A series of parameters including PI, LL, PI-LL, thoracic kyphosis (TK), pelvic tilt (PT), sacral slope (SS), knee flexion angle (KFA), tibial obliquity angle (TOA), sagittal vertical axis (SVA), S1 overhang, femoral head shift (FHS), and pelvic shift (PS) were measured and compared among the three groups. The severe PI-LL mismatch group exhibited significantly greater PI, PI-LL, PT, KFA, SVA, PS, and FHS, and less LL and TK, compared with the control and mild PI-LL mismatch group. The mild PI-LL mismatch group had significantly greater PI-LL, PT, KFA, TOA, and S1 overhang, and less LL and SS than the control group. SS, TOA, and S1 overhang in the severe PI-LL mismatch group differed significantly from that in the control group, but did not differ significantly from that in the mild PI-LL mismatch group. Femoral head retroposition is an entirely separate compensatory mechanism and, in this study, participated in the compensation for the anterior displacement of the gravity line induced by extra-sagittal spinal malalignment in patients with severe PI-LL mismatch.

  11. Current-based detection of nonlocal spin transport in graphene for spin-based logic applications

    Science.gov (United States)

    Wen, Hua; Zhu, Tiancong; Luo, Yunqiu Kelly; Amamou, Walid; Kawakami, Roland K.

    2014-05-01

    Graphene has been proposed for novel spintronic devices due to its robust and efficient spin transport properties at room temperature. Some of the most promising proposals require current-based readout for integration purposes, but the current-based detection of spin accumulation has not yet been developed. In this work, we demonstrate current-based detection of spin transport in graphene using a modified nonlocal geometry. By adding a variable shunt resistor in parallel to the nonlocal voltmeter, we are able to systematically cross over from the conventional voltage-based detection to current-based detection. As the shunt resistor is reduced, the output current from the spin accumulation increases as the shunt resistance drops below a characteristic value R*. We analyze this behavior using a one-dimensional drift-diffusion model, which accounts well for the observed behavior. These results provide the experimental and theoretical foundation for current-based detection of nonlocal spin transport.

  12. Observer-Based and Regression Model-Based Detection of Emerging Faults in Coal Mills

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Lin, Bao; Jørgensen, Sten Bay

    2006-01-01

    In order to improve the reliability of power plants it is important to detect fault as fast as possible. Doing this it is interesting to find the most efficient method. Since modeling of large scale systems is time consuming it is interesting to compare a model-based method with data driven ones....... In this paper three different fault detection approaches are compared using a example of a coal mill, where a fault emerges. The compared methods are based on: an optimal unknown input observer, static and dynamic regression model-based detections. The conclusion on the comparison is that observer-based scheme...... detects the fault 13 samples earlier than the dynamic regression model-based method, and that the static regression based method is not usable due to generation of far too many false detections....

  13. Abnormal Appearance Detection of Substation Based on Image Comparison

    Directory of Open Access Journals (Sweden)

    Zhang Xu

    2016-01-01

    Full Text Available Based on image comparison, a novel algorithm for abnormal appearance detection of substation is proposed. Previous spatial states of an object are compared to its current representation in a digital image. Firstly, saliency maps are acquired using a fast implementation method of salient region detection. Based on saliency maps, image registration was completed by ORB (Oriented Fast and Rotated Brief. Then, sliding widow algorithm is applied to transform the whole image comparison problem into sub-image comparison problem. Textural feature and shape feature vectors (TSFVs representing contents of images are generated by feature level fusion. Finally, decisions are automatically made as to whether or not change at the outline has occurred by the Euclidean distance of TEFVs. Experimental results show that the proposed method has good performance in abnormal appearance detection of substation.

  14. DNA-based species detection capabilities using laser transmission spectroscopy.

    Science.gov (United States)

    Mahon, A R; Barnes, M A; Li, F; Egan, S P; Tanner, C E; Ruggiero, S T; Feder, J L; Lodge, D M

    2013-01-06

    Early detection of invasive species is critical for effective biocontrol to mitigate potential ecological and economic damage. Laser transmission spectroscopy (LTS) is a powerful solution offering real-time, DNA-based species detection in the field. LTS can measure the size, shape and number of nanoparticles in a solution and was used here to detect size shifts resulting from hybridization of the polymerase chain reaction product to nanoparticles functionalized with species-specific oligonucleotide probes or with the species-specific oligonucleotide probes alone. We carried out a series of DNA detection experiments using the invasive freshwater quagga mussel (Dreissena bugensis) to evaluate the capability of the LTS platform for invasive species detection. Specifically, we tested LTS sensitivity to (i) DNA concentrations of a single target species, (ii) the presence of a target species within a mixed sample of other closely related species, (iii) species-specific functionalized nanoparticles versus species-specific oligonucleotide probes alone, and (iv) amplified DNA fragments versus unamplified genomic DNA. We demonstrate that LTS is a highly sensitive technique for rapid target species detection, with detection limits in the picomolar range, capable of successful identification in multispecies samples containing target and non-target species DNA. These results indicate that the LTS DNA detection platform will be useful for field application of target species. Additionally, we find that LTS detection is effective with species-specific oligonucleotide tags alone or when they are attached to polystyrene nanobeads and with both amplified and unamplified DNA, indicating that the technique may also have versatility for broader applications.

  15. Feature versus gestalt representation of stimuli in the mismatch negativity system of 7- to 9-year-old children.

    Science.gov (United States)

    Molholm, Sophie; Gomes, Hilary; Lobosco, Jacqueline; Deacon, Diana; Ritter, Walter

    2004-05-01

    We examined preattentive auditory change detection in 7- to 9-year-old children. The question of interest was whether the preattentive comparison of stimuli indexed by the scalp-recorded mismatch negativity (MMN) was performed on representations of individual stimulus features or on gestalt representations of their combined attributes. The design of the study, based on a work by D. Deacon, J. Nousak, M. Pilotti, W. Ritter, and C. Yang (Psychophysiology, 1998), was such that both feature and gestalt representations could have been available to the comparator mechanism generating the MMN. The data indicated that for the majority of the children-those that exhibited an inverse relationship between the amplitude of the MMN and the probability of the deviant-the MMN was based on feature-specific information. This study also provides a method to obtain MMNs to deviants in three different features in the time usually required to obtain an MMN to a single acoustic feature.

  16. Feature selection for fMRI-based deception detection

    Science.gov (United States)

    Jin, Bo; Strasburger, Alvin; Laken, Steven J; Kozel, F Andrew; Johnson, Kevin A; George, Mark S; Lu, Xinghua

    2009-01-01

    Background Functional magnetic resonance imaging (fMRI) is a technology used to detect brain activity. Patterns of brain activation have been utilized as biomarkers for various neuropsychiatric applications. Detecting deception based on the pattern of brain activation characterized with fMRI is getting attention – with machine learning algorithms being applied to this field in recent years. The high dimensionality of fMRI data makes it a difficult task to directly utilize the original data as input for classification algorithms in detecting deception. In this paper, we investigated the procedures of feature selection to enhance fMRI-based deception detection. Results We used the t-statistic map derived from the statistical parametric mapping analysis of fMRI signals to construct features that reflect brain activation patterns. We subsequently investigated various feature selection methods including an ensemble method to identify discriminative features to detect deception. Using 124 features selected from a set of 65,166 original features as inputs for a support vector machine classifier, our results indicate that feature selection significantly enhanced the classification accuracy of the support vector machine in comparison to the models trained using all features and dimension reduction based models. Furthermore, the selected features are shown to form anatomic clusters within brain regions, which supports the hypothesis that specific brain regions may play a role during deception processes. Conclusion Feature selection not only enhances classification accuracy in fMRI-based deception detection but also provides support for the biological hypothesis that brain activities in certain regions of the brain are important for discrimination of deception. PMID:19761569

  17. Effect of the degree of polar mismatching on traffic jam formation in fast axonal transport.

    Science.gov (United States)

    Kuznetsov, A V

    2010-12-01

    This paper simulates an axon with a region of reversed microtubule (MT) polarity, and investigates how the degree of polar mismatching in this region affects the formation of organelle traps in the axon. The model is based on modified Smith-Simmons equations governing molecular-motor-assisted transport in neurons. It is established that the structure that develops as a result of a region with disoriented MTs consists of two organelle traps, the trap to the left of this region accumulates plus-end-oriented organelles and the trap to the right of this region accumulates minus-end-oriented organelles. The presence of such a structure is shown to inhibit the transport of organelles down the axon. The degree by which the transport of organelles is inhibited depends on the degree of polar mismatching of MTs in the region between MT traps. Four cases with a different degree of polar mismatching are investigated.

  18. An IQ mismatch calibration and compensation technique for wideband wireless transceivers

    International Nuclear Information System (INIS)

    Peng Jin; Zhou Liguo; Yao Heng; Yuan Fang; Shi Yin; Fang Zhi

    2014-01-01

    An IQ mismatch calibration and compensation technique based on the digital baseband for wideband wireless communication transmitters is proposed. The digital baseband transmits the signal used for IQ mismatch calibration. The signal passes through the RF transmitter path, the calibration loop (which is composed of a square power detector and a band-pass filter in the RF transceiver) and the variable gain amplifier of the receiver. The digital baseband samples the signal for IQ mismatch estimation and compensates for it. Compared with the self-calibration technique in the RF chip, the proposed technique saves area and power consumption for the wireless local area network solution. This technique has been successfully used for the 802.11n system and satisfies the requirement of the standard by achieving over 50 dB image suppression. (semiconductor integrated circuits)

  19. An IQ mismatch calibration and compensation technique for wideband wireless transceivers

    Science.gov (United States)

    Jin, Peng; Liguo, Zhou; Heng, Yao; Fang, Yuan; Zhi, Fang; Yin, Shi

    2014-08-01

    An IQ mismatch calibration and compensation technique based on the digital baseband for wideband wireless communication transmitters is proposed. The digital baseband transmits the signal used for IQ mismatch calibration. The signal passes through the RF transmitter path, the calibration loop (which is composed of a square power detector and a band-pass filter in the RF transceiver) and the variable gain amplifier of the receiver. The digital baseband samples the signal for IQ mismatch estimation and compensates for it. Compared with the self-calibration technique in the RF chip, the proposed technique saves area and power consumption for the wireless local area network solution. This technique has been successfully used for the 802.11n system and satisfies the requirement of the standard by achieving over 50 dB image suppression.

  20. Monte Carlo techniques to analyse the electrical mismatch losses in large-scale photovoltaic generators

    Energy Technology Data Exchange (ETDEWEB)

    Iannone, F.; Sarno, A. [ENEA, Portici (Italy). Research Center; Noviello, G. [ENEA, Manfredonia (Italy). Mt. Aquilone Test-Side

    1998-02-01

    In large-scale photovoltaic generators, the arrangement of modules with different electrical characteristics could involve a considerable mismatch between the single components resulting in a power loss. This means the actual power is less than the sum of the maximum output powers of the individual PV modules, operating at the same irradiance-temperature conditions. To reduce the mismatch losses and to calculate it under operating conditions, a statistical approach based on Monte Carlo simulation techniques, has been developed and validated. The simulation model shows that it is possible to meet the required mismatch level, with a random arrangement, starting from a modules population characterized in terms of short circuit current, I{sub SC} and open circuit voltage V{sub OC}, by a probability density function with a imposed variance. The method has been successfully applied for a 100 kWp standard unit photovoltaic generator, the computational results have shown good agreement with the experimental data. (author)

  1. Receiver IQ mismatch estimation in PDM CO-OFDM system using training symbol

    Science.gov (United States)

    Peng, Dandan; Ma, Xiurong; Yao, Xin; Zhang, Haoyuan

    2017-07-01

    Receiver in-phase/quadrature (IQ) mismatch is hard to mitigate at the receiver via using conventional method in polarization division multiplexed (PDM) coherent optical orthogonal frequency division multiplexing (CO-OFDM) system. In this paper, a novel training symbol structure is proposed to estimate IQ mismatch and channel distortion. Combined this structure with Gram Schmidt orthogonalization procedure (GSOP) algorithm, we can get lower bit error rate (BER). Meanwhile, based on this structure one estimation method is deduced in frequency domain which can achieve the estimation of IQ mismatch and channel distortion independently and improve the system performance obviously. Numerical simulation shows that the proposed two methods have better performance than compared method at 100 Gb/s after 480 km fiber transmission. Besides, the calculation complexity is also analyzed.

  2. Fast Content-Based Packet Handling for Intrusion Detection

    National Research Council Canada - National Science Library

    Fisk, Mike

    2001-01-01

    ... use of Royer-Moore currently used in the popular intrusion detection platform Snort. We then measure the actual performance of several search algorithms on actual packet traces and rulesets. Our results provide lessons on the structuring of content-based handlers.

  3. An Astigmatic Detection System for Polymeric Cantilever-based Sensors

    DEFF Research Database (Denmark)

    Hwu, En-Te; Liao, Hsien-Shun; Bosco, Filippo

    2012-01-01

    We demonstrate the use of an astigmatic detection system (ADS) for resonance frequency identification of polymer microcantilever sensors. The ADS technology is based on a DVD optical head combined with an optical microscope (OM). The optical head has a signal bandwidth of 80 MHz, allowing thermal...

  4. REGION BASED FOREST CHANGE DETECTION FROM CARTOSAT-1 STEREO IMAGERY

    Directory of Open Access Journals (Sweden)

    J. Tian

    2012-09-01

    Full Text Available Tree height is a fundamental parameter for describing the forest situation and changes. The latest development of automatic Digital Surface Model (DSM generation techniques allows new approaches of forest change detection from satellite stereo imagery. This paper shows how DSMs can support the change detection in forest area. A novel region based forest change detection method is proposed using single-channel CARTOSAT-1 stereo imagery. In the first step, DSMs from two dates are generated based on automatic matching technology. After co-registration and normalising by using LiDAR data, the mean-shift segmentation is applied to the original pan images, and the images of both dates are classified to forest and non-forest areas by analysing their histograms and height differences. In the second step, a rough forest change detection map is generated based on the comparison of the two forest map. Then the GLCM texture from the nDSM and the Cartosat-1 images of the resulting regions are analyzed and compared, the real changes are extracted by SVM based classification.

  5. GIS-based Integration of Interdisciplinary Ecological Data to Detect ...

    African Journals Online (AJOL)

    GIS-based Integration of Interdisciplinary Ecological Data to Detect Land-cover Changes in Creek Mangroves at Gazi Bay, Kenya. ... Very low values of basal area (7.7 m2/ha and 4.9 m2/ha) and complexity indices (1.86 and 1.12) at Makongeni and Kinondo 1, respectively, reflected intense human pressure in these areas.

  6. PCR-based detection of allergenic mackerel ingredients in seafood

    Indian Academy of Sciences (India)

    Administrator

    Keywords. Scomber mackerel; allergy; seafood; PCR; genus identification. RESEARCH NOTE. PCR-based detection of allergenic mackerel ingredients in seafood. FUTOSHI ARANISHI 1,* and TAKANE OKIMOTO 1,2. 1Department of Biological and Environmental Sciences, Miyazaki University,. Miyazaki 889-2192, Japan.

  7. The harmonics detection method based on neural network applied ...

    African Journals Online (AJOL)

    The harmonics detection method based on neural network applied to harmonics compensation. R Dehini, A Bassou, B Ferdi. Abstract. Several different methods have been used to sense load currents and extract its harmonic component in order to produce a reference current in shunt active power filters (SAPF), and to ...

  8. Detecting Hacked Twitter Accounts based on Behavioural Change

    NARCIS (Netherlands)

    Nauta, Meike; Habib, Mena Badieh; van Keulen, Maurice

    Social media accounts are valuable for hackers for spreading phishing links, malware and spam. Furthermore, some people deliberately hack an acquaintance to damage his or her image. This paper describes a classification for detecting hacked Twitter accounts. The model is mainly based on features

  9. Machine learning for network-based malware detection

    DEFF Research Database (Denmark)

    Stevanovic, Matija

    using traffic traces from honeypots and malware testing environments as well as operational ISP networks. Based on the evaluation, the novel detection methods provide accurate and efficient identification of malicious network traffic, thus being promising in the light of operational deployment...

  10. A proposed data base system for detection, classification and ...

    African Journals Online (AJOL)

    A proposed data base system for detection, classification and location of fault on electricity company of Ghana electrical distribution system. Isaac Owusu-Nyarko, Mensah-Ananoo Eugine. Abstract. No Abstract. Keywords: database, classification of fault, power, distribution system, SCADA, ECG. Full Text: EMAIL FULL TEXT ...

  11. Phishing Detection: Analysis of Visual Similarity Based Approaches

    Directory of Open Access Journals (Sweden)

    Ankit Kumar Jain

    2017-01-01

    Full Text Available Phishing is one of the major problems faced by cyber-world and leads to financial losses for both industries and individuals. Detection of phishing attack with high accuracy has always been a challenging issue. At present, visual similarities based techniques are very useful for detecting phishing websites efficiently. Phishing website looks very similar in appearance to its corresponding legitimate website to deceive users into believing that they are browsing the correct website. Visual similarity based phishing detection techniques utilise the feature set like text content, text format, HTML tags, Cascading Style Sheet (CSS, image, and so forth, to make the decision. These approaches compare the suspicious website with the corresponding legitimate website by using various features and if the similarity is greater than the predefined threshold value then it is declared phishing. This paper presents a comprehensive analysis of phishing attacks, their exploitation, some of the recent visual similarity based approaches for phishing detection, and its comparative study. Our survey provides a better understanding of the problem, current solution space, and scope of future research to deal with phishing attacks efficiently using visual similarity based approaches.

  12. Section based traffic detection on motorways for incident management

    NARCIS (Netherlands)

    Noort, M. van; Klunder, G.

    2007-01-01

    Current vehicle detection on motorways is based generally on either inductive loop systems or various alternatives such as video cameras. Recently, we encountered two new developments that take a different approach: one from The Netherlands using microwave sensors, and the other from Sweden using

  13. Understanding the Mismatch Between Coaches' and Players' Perceptions of Exertion.

    Science.gov (United States)

    Brink, Michel S; Kersten, Anna W; Frencken, Wouter G P

    2017-04-01

    A mismatch between the training exertion intended by a coach and the exertion perceived by players is well established in sports. However, it is unknown whether coaches can accurately observe exertion of individual players during training. Furthermore, the discrepancy in coaches' and players' perceptions has not been explained. To determine the relation between intended and observed training exertion by the coach and perceived training exertion by the players and establish whether on-field training characteristics, intermittent endurance capacity, and maturity status explain the mismatch. During 2 mesocycles of 4 wk (in November and March), rating of intended exertion (RIE), rating of observed exertion (ROE), and rating of perceived exertion (RPE) were monitored in 31 elite young soccer players. External and internal training loads were objectively quantified with accelerometers (PlayerLoad) and heart-rate monitors (TRIMPmod). Results of an interval shuttle-run test (ISRT) and age at peak height velocity (APHV) were determined for all players. RIE, ROE, and RPE were monitored in 977 training sessions. The correlations between RIE and RPE (r = .58; P base their intended and observed exertion on what they expect players will do and what they actually did on the field. When doing this, they consider the intermittent endurance capacity of individual players.

  14. Citation-based plagiarism detection detecting disguised and cross-language plagiarism using citation pattern analysis

    CERN Document Server

    Gipp, Bela

    2014-01-01

    Plagiarism is a problem with far-reaching consequences for the sciences. However, even today's best software-based systems can only reliably identify copy & paste plagiarism. Disguised plagiarism forms, including paraphrased text, cross-language plagiarism, as well as structural and idea plagiarism often remain undetected. This weakness of current systems results in a large percentage of scientific plagiarism going undetected. Bela Gipp provides an overview of the state-of-the art in plagiarism detection and an analysis of why these approaches fail to detect disguised plagiarism forms. The aut

  15. Visual mismatch negativity: a predictive coding view

    Science.gov (United States)

    Stefanics, Gábor; Kremláček, Jan; Czigler, István

    2014-01-01

    An increasing number of studies investigate the visual mismatch negativity (vMMN) or use the vMMN as a tool to probe various aspects of human cognition. This paper reviews the theoretical underpinnings of vMMN in the light of methodological considerations and provides recommendations for measuring and interpreting the vMMN. The following key issues are discussed from the experimentalist's point of view in a predictive coding framework: (1) experimental protocols and procedures to control “refractoriness” effects; (2) methods to control attention; (3) vMMN and veridical perception. PMID:25278859

  16. Family-Based Benchmarking of Copy Number Variation Detection Software.

    Science.gov (United States)

    Nutsua, Marcel Elie; Fischer, Annegret; Nebel, Almut; Hofmann, Sylvia; Schreiber, Stefan; Krawczak, Michael; Nothnagel, Michael

    2015-01-01

    The analysis of structural variants, in particular of copy-number variations (CNVs), has proven valuable in unraveling the genetic basis of human diseases. Hence, a large number of algorithms have been developed for the detection of CNVs in SNP array signal intensity data. Using the European and African HapMap trio data, we undertook a comparative evaluation of six commonly used CNV detection software tools, namely Affymetrix Power Tools (APT), QuantiSNP, PennCNV, GLAD, R-gada and VEGA, and assessed their level of pair-wise prediction concordance. The tool-specific CNV prediction accuracy was assessed in silico by way of intra-familial validation. Software tools differed greatly in terms of the number and length of the CNVs predicted as well as the number of markers included in a CNV. All software tools predicted substantially more deletions than duplications. Intra-familial validation revealed consistently low levels of prediction accuracy as measured by the proportion of validated CNVs (34-60%). Moreover, up to 20% of apparent family-based validations were found to be due to chance alone. Software using Hidden Markov models (HMM) showed a trend to predict fewer CNVs than segmentation-based algorithms albeit with greater validity. PennCNV yielded the highest prediction accuracy (60.9%). Finally, the pairwise concordance of CNV prediction was found to vary widely with the software tools involved. We recommend HMM-based software, in particular PennCNV, rather than segmentation-based algorithms when validity is the primary concern of CNV detection. QuantiSNP may be used as an additional tool to detect sets of CNVs not detectable by the other tools. Our study also reemphasizes the need for laboratory-based validation, such as qPCR, of CNVs predicted in silico.

  17. Pedestrian detection from thermal images: A sparse representation based approach

    Science.gov (United States)

    Qi, Bin; John, Vijay; Liu, Zheng; Mita, Seiichi

    2016-05-01

    Pedestrian detection, a key technology in computer vision, plays a paramount role in the applications of advanced driver assistant systems (ADASs) and autonomous vehicles. The objective of pedestrian detection is to identify and locate people in a dynamic environment so that accidents can be avoided. With significant variations introduced by illumination, occlusion, articulated pose, and complex background, pedestrian detection is a challenging task for visual perception. Different from visible images, thermal images are captured and presented with intensity maps based objects' emissivity, and thus have an enhanced spectral range to make human beings perceptible from the cool background. In this study, a sparse representation based approach is proposed for pedestrian detection from thermal images. We first adopted the histogram of sparse code to represent image features and then detect pedestrian with the extracted features in an unimodal and a multimodal framework respectively. In the unimodal framework, two types of dictionaries, i.e. joint dictionary and individual dictionary, are built by learning from prepared training samples. In the multimodal framework, a weighted fusion scheme is proposed to further highlight the contributions from features with higher separability. To validate the proposed approach, experiments were conducted to compare with three widely used features: Haar wavelets (HWs), histogram of oriented gradients (HOG), and histogram of phase congruency (HPC) as well as two classification methods, i.e. AdaBoost and support vector machine (SVM). Experimental results on a publicly available data set demonstrate the superiority of the proposed approach.

  18. A Wavelet-Based Approach to Fall Detection

    Directory of Open Access Journals (Sweden)

    Luca Palmerini

    2015-05-01

    Full Text Available Falls among older people are a widely documented public health problem. Automatic fall detection has recently gained huge importance because it could allow for the immediate communication of falls to medical assistance. The aim of this work is to present a novel wavelet-based approach to fall detection, focusing on the impact phase and using a dataset of real-world falls. Since recorded falls result in a non-stationary signal, a wavelet transform was chosen to examine fall patterns. The idea is to consider the average fall pattern as the “prototype fall”.In order to detect falls, every acceleration signal can be compared to this prototype through wavelet analysis. The similarity of the recorded signal with the prototype fall is a feature that can be used in order to determine the difference between falls and daily activities. The discriminative ability of this feature is evaluated on real-world data. It outperforms other features that are commonly used in fall detection studies, with an Area Under the Curve of 0.918. This result suggests that the proposed wavelet-based feature is promising and future studies could use this feature (in combination with others considering different fall phases in order to improve the performance of fall detection algorithms.

  19. Saliency detection algorithm based on LSC-RC

    Science.gov (United States)

    Wu, Wei; Tian, Weiye; Wang, Ding; Luo, Xin; Wu, Yingfei; Zhang, Yu

    2018-02-01

    Image prominence is the most important region in an image, which can cause the visual attention and response of human beings. Preferentially allocating the computer resources for the image analysis and synthesis by the significant region is of great significance to improve the image area detecting. As a preprocessing of other disciplines in image processing field, the image prominence has widely applications in image retrieval and image segmentation. Among these applications, the super-pixel segmentation significance detection algorithm based on linear spectral clustering (LSC) has achieved good results. The significance detection algorithm proposed in this paper is better than the regional contrast ratio by replacing the method of regional formation in the latter with the linear spectral clustering image is super-pixel block. After combining with the latest depth learning method, the accuracy of the significant region detecting has a great promotion. At last, the superiority and feasibility of the super-pixel segmentation detection algorithm based on linear spectral clustering are proved by the comparative test.

  20. A wavelet-based approach to fall detection.

    Science.gov (United States)

    Palmerini, Luca; Bagalà, Fabio; Zanetti, Andrea; Klenk, Jochen; Becker, Clemens; Cappello, Angelo

    2015-05-20

    Falls among older people are a widely documented public health problem. Automatic fall detection has recently gained huge importance because it could allow for the immediate communication of falls to medical assistance. The aim of this work is to present a novel wavelet-based approach to fall detection, focusing on the impact phase and using a dataset of real-world falls. Since recorded falls result in a non-stationary signal, a wavelet transform was chosen to examine fall patterns. The idea is to consider the average fall pattern as the "prototype fall".In order to detect falls, every acceleration signal can be compared to this prototype through wavelet analysis. The similarity of the recorded signal with the prototype fall is a feature that can be used in order to determine the difference between falls and daily activities. The discriminative ability of this feature is evaluated on real-world data. It outperforms other features that are commonly used in fall detection studies, with an Area Under the Curve of 0.918. This result suggests that the proposed wavelet-based feature is promising and future studies could use this feature (in combination with others considering different fall phases) in order to improve the performance of fall detection algorithms.

  1. Vision Sensor-Based Road Detection for Field Robot Navigation

    Directory of Open Access Journals (Sweden)

    Keyu Lu

    2015-11-01

    Full Text Available Road detection is an essential component of field robot navigation systems. Vision sensors play an important role in road detection for their great potential in environmental perception. In this paper, we propose a hierarchical vision sensor-based method for robust road detection in challenging road scenes. More specifically, for a given road image captured by an on-board vision sensor, we introduce a multiple population genetic algorithm (MPGA-based approach for efficient road vanishing point detection. Superpixel-level seeds are then selected in an unsupervised way using a clustering strategy. Then, according to the GrowCut framework, the seeds proliferate and iteratively try to occupy their neighbors. After convergence, the initial road segment is obtained. Finally, in order to achieve a globally-consistent road segment, the initial road segment is refined using the conditional random field (CRF framework, which integrates high-level information into road detection. We perform several experiments to evaluate the common performance, scale sensitivity and noise sensitivity of the proposed method. The experimental results demonstrate that the proposed method exhibits high robustness compared to the state of the art.

  2. Colorimetric detection of cholesterol based on enzyme modified gold nanoparticles

    Science.gov (United States)

    Nirala, Narsingh R.; Saxena, Preeti S.; Srivastava, Anchal

    2018-02-01

    We develop a simple colorimetric method for determination of free cholesterol in aqueous solution based on functionalized gold nanoparticles with cholesterol oxidase. Functionalized gold nanoparticles interact with free cholesterol to produce H2O2 in proportion to the level of cholesterol visually is being detected. The quenching in optical properties and agglomeration of functionalized gold nanoparticles play a key role in cholesterol sensing due to the electron accepting property of H2O2. While the lower ranges of cholesterol (lower detection limit i.e. 0.2 mg/dL) can be effectively detected using fluorescence study, the absorption study attests evident visual color change which becomes effective for detection of higher ranges of cholesterol (lower detection limit i.e. 19 mg/dL). The shades of red gradually change to blue/purple as the level of cholesterol detected (as evident at 100 mg/dL) using unaided eye without the use of expensive instruments. The potential of the proposed method to be applied in the field is shown by the proposed cholesterol measuring color wheel.

  3. Wideband Array Signal Detection Algorithm Based on Power Focusing

    Directory of Open Access Journals (Sweden)

    Gong Bin

    2012-09-01

    Full Text Available Aiming at the requirement of real-time signal detection in the passive surveillance system, a wideband array signal detection algorithm is proposed based on the concept of power focusing. By making use of the phase difference of the signal received by a uniform linear array, the algorithm makes the power of the received signal focused in the Direction Of Arrival (DOA with improved cascade FFT. Subsequently, the probability density function of the output noise at each angle is derived. Furthermore, a Constant False Alarm Rate (CFAR test statistic and the corresponding detection threshold are constructed. The theoretical probability of detection is also derived for different false alarm rate and Signal-to-Noise Ratio (SNR. The proposed algorithm is computationally efficient, and the detection process is independent of the prior information. Meanwhile, the results can act as the initial value for other algorithms with higher precision. Simulation results show that the proposed algorithm achieves good performance for weak signal detection.

  4. A Viola-Jones based hybrid face detection framework

    Science.gov (United States)

    Murphy, Thomas M.; Broussard, Randy; Schultz, Robert; Rakvic, Ryan; Ngo, Hau

    2013-12-01

    Improvements in face detection performance would benefit many applications. The OpenCV library implements a standard solution, the Viola-Jones detector, with a statistically boosted rejection cascade of binary classifiers. Empirical evidence has shown that Viola-Jones underdetects in some instances. This research shows that a truncated cascade augmented by a neural network could recover these undetected faces. A hybrid framework is constructed, with a truncated Viola-Jones cascade followed by an artificial neural network, used to refine the face decision. Optimally, a truncation stage that captured all faces and allowed the neural network to remove the false alarms is selected. A feedforward backpropagation network with one hidden layer is trained to discriminate faces based upon the thresholding (detection) values of intermediate stages of the full rejection cascade. A clustering algorithm is used as a precursor to the neural network, to group significant overlappings. Evaluated on the CMU/VASC Image Database, comparison with an unmodified OpenCV approach shows: (1) a 37% increase in detection rates if constrained by the requirement of no increase in false alarms, (2) a 48% increase in detection rates if some additional false alarms are tolerated, and (3) an 82% reduction in false alarms with no reduction in detection rates. These results demonstrate improved face detection and could address the need for such improvement in various applications.

  5. Disposable amperometric biosensor based on nanostructured bacteriophages for glucose detection

    International Nuclear Information System (INIS)

    Kang, Yu Ri; Kim, Ju Hwan; Kim, Soo Won; Hwang, Kyung Hoon; Nam, Chang Hoon

    2010-01-01

    The selection of electrode material profoundly influences biosensor science and engineering, as it heavily influences biosensor sensitivity. Here we propose a novel electrochemical detection method using a working electrode consisting of bio-nanowires from genetically modified filamentous phages and nanoparticles. fd-tet p8MMM filamentous phages displaying a three-methionine (MMM) peptide on the major coat protein pVIII (designated p8MMM phages) were immobilized on the active area of an electrochemical sensor through physical adsorption and chemical bonding. Bio-nanowires composed of p8MMM phages and silver nanoparticles facilitated sensitive, rapid and selective detection of particular molecules. We explored whether the composite electrode with bio-nanowires was an effective platform to detect the glucose oxidase. The current response of the bio-nanowire sensor was high at various glucose concentrations (0.1 µm–0.1 mM). This method provides a considerable advantage to demonstrate analyte detection over low concentration ranges. Especially, phage-enabled bio-nanowires can serve as receptors with high affinity and specificity for the detection of particular biomolecules and provide a convenient platform for designing site-directed multifunctional scaffolds based on bacteriophages and may serve as a simple method for label-free detection

  6. Immunomagnetic nanoparticle based quantitative PCR for rapid detection of Salmonella

    International Nuclear Information System (INIS)

    Bakthavathsalam, Padmavathy; Rajendran, Vinoth Kumar; Saran, Uttara; Chatterjee, Suvro; Ali, Baquir Mohammed Jaffar

    2013-01-01

    We have developed a rapid and sensitive method for immunomagnetic separation (IMS) of Salmonella along with their real time detection via PCR. Silica-coated magnetic nanoparticles were functionalized with carboxy groups to which anti-Salmonella antibody raised against heat-inactivated whole cells of Salmonella were covalently attached. The immuno-captured target cells were detected in beverages like milk and lemon juice by multiplex PCR and real time PCR with a detection limit of 10 4 cfu.mL −1 and 10 3 cfu.mL −1 , respectively. We demonstrate that IMS can be used for selective concentration of target bacteria from beverages for subsequent use in PCR detection. PCR also enables differentiation of Salmonella typhi and Salmonella paratyphi A using a set of four specific primers. In addition, IMS—PCR can be used as a screening tool in the food and beverage industry for the detection of Salmonella within 3–4 h which compares favorably to the time of several days that is needed in case of conventional detection based on culture and biochemical methods. (author)

  7. Paper-based Platform for Urinary Creatinine Detection.

    Science.gov (United States)

    Sittiwong, Jarinya; Unob, Fuangfa

    2016-01-01

    A new paper platform was developed for the colorimetric detection of creatinine. The filter paper was coated with 3-propylsulfonic acid trimethoxysilane and used as the platform. Creatinine in a cationic form was extracted onto the paper via an ion-exchange mechanism and detected through the Jaffé reaction, resulting in a yellow-orange color complex. The color change on the paper could be observed visually, and the quantitative detection of creatinine was achieved through monitoring the color intensity change. The color intensity of creatinine complexes on the paper platform as a function of the creatinine concentration provided a linear range for creatinine detection in the range of 10 - 60 mg L(-1) and a detection limit of 4.2 mg L(-1). The accuracy of the proposed paper-based method was comparable to the conventional standard Jaffé method. This paper platform could be applied for simple and rapid detection of creatinine in human urine samples with a low consumption of reagent.

  8. Designing of highly effective complementary and mismatch siRNAs for silencing a gene.

    Science.gov (United States)

    Ahmed, Firoz; Raghava, Gajendra P S

    2011-01-01

    In past, numerous methods have been developed for predicting efficacy of short interfering RNA (siRNA). However these methods have been developed for predicting efficacy of fully complementary siRNA against a gene. Best of author's knowledge no method has been developed for predicting efficacy of mismatch siRNA against a gene. In this study, a systematic attempt has been made to identify highly effective complementary as well as mismatch siRNAs for silencing a gene.Support vector machine (SVM) based models have been developed for predicting efficacy of siRNAs using composition, binary and hybrid pattern siRNAs. We achieved maximum correlation 0.67 between predicted and actual efficacy of siRNAs using hybrid model. All models were trained and tested on a dataset of 2182 siRNAs and performance was evaluated using five-fold cross validation techniques. The performance of our method desiRm is comparable to other well-known methods. In this study, first time attempt has been made to design mutant siRNAs (mismatch siRNAs). In this approach we mutated a given siRNA on all possible sites/positions with all possible nucleotides. Efficacy of each mutated siRNA is predicted using our method desiRm. It is well known from literature that mismatches between siRNA and target affects the silencing efficacy. Thus we have incorporated the rules derived from base mismatches experimental data to find out over all efficacy of mutated or mismatch siRNAs. Finally we developed a webserver, desiRm (http://www.imtech.res.in/raghava/desirm/) for designing highly effective siRNA for silencing a gene. This tool will be helpful to design siRNA to degrade disease isoform of heterozygous single nucleotide polymorphism gene without depleting the wild type protein.

  9. Convergent transmission of RNAi guide-target mismatch information across Argonaute internal allosteric network.

    Directory of Open Access Journals (Sweden)

    Thomas T Joseph

    Full Text Available In RNA interference, a guide strand derived from a short dsRNA such as a microRNA (miRNA is loaded into Argonaute, the central protein in the RNA Induced Silencing Complex (RISC that silences messenger RNAs on a sequence-specific basis. The positions of any mismatched base pairs in an miRNA determine which Argonaute subtype is used. Subsequently, the Argonaute-guide complex binds and silences complementary target mRNAs; certain Argonautes cleave the target. Mismatches between guide strand and the target mRNA decrease cleavage efficiency. Thus, loading and silencing both require that signals about the presence of a mismatched base pair are communicated from the mismatch site to effector sites. These effector sites include the active site, to prevent target cleavage; the binding groove, to modify nucleic acid binding affinity; and surface allosteric sites, to control recruitment of additional proteins to form the RISC. To examine how such signals may be propagated, we analyzed the network of internal allosteric pathways in Argonaute exhibited through correlations of residue-residue interactions. The emerging network can be described as a set of pathways emanating from the core of the protein near the active site, distributed into the bulk of the protein, and converging upon a distributed cluster of surface residues. Nucleotides in the guide strand "seed region" have a stronger relationship with the protein than other nucleotides, concordant with their importance in sequence selectivity. Finally, any of several seed region guide-target mismatches cause certain Argonaute residues to have modified correlations with the rest of the protein. This arises from the aggregation of relatively small interaction correlation changes distributed across a large subset of residues. These residues are in effector sites: the active site, binding groove, and surface, implying that direct functional consequences of guide-target mismatches are mediated through the

  10. Vision-based threat detection in dynamic environments.

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Jeffrey J.

    2007-08-01

    This report addresses the development of automated video-screening technology to assist security forces in protecting our homeland against terrorist threats. A prevailing threat is the covert placement of bombs inside crowded public facilities. Although video-surveillance systems are increasingly common, current systems cannot detect the placement of bombs. It is also unlikely that security personnel could detect a bomb or its placement by observing video from surveillance cameras. The problems lie in the large number of cameras required to monitor large areas, the limited number of security personnel employed to protect these areas, and the intense diligence required to effectively screen live video from even a single camera. Different from existing video-detection systems designed to operate in nearly static environments, we are developing technology to detect changes in the background of dynamic environments: environments where motion and human activities are persistent over long periods. Our goal is to quickly detect background changes, even if the background is visible to the camera less than 5 percent of the time and possibly never free from foreground activity. Our approach employs statistical scene models based on mixture densities. We hypothesized that the background component of the mixture has a small variance compared to foreground components. Experiments demonstrate this hypothesis is true under a wide variety of operating conditions. A major focus involved the development of robust background estimation techniques that exploit this property. We desire estimation algorithms that can rapidly produce accurate background estimates and detection algorithms that can reliably detect background changes with minimal nuisance alarms. Another goal is to recognize unusual activities or foreground conditions that could signal an attack (e.g., large numbers of running people, people falling to the floor, etc.). Detection of background changes and/or unusual

  11. Detecting epileptic regions based on global brain connectivity patterns.

    Science.gov (United States)

    Sweet, Andrew; Venkataraman, Archana; Stufflebeam, Steven M; Liu, Hesheng; Tanaka, Naoro; Madsen, Joseph; Golland, Polina

    2013-01-01

    We present a method to detect epileptic regions based on functional connectivity differences between individual epilepsy patients and a healthy population. Our model assumes that the global functional characteristics of these differences are shared across patients, but it allows for the epileptic regions to vary between individuals. We evaluate the detection performance against intracranial EEG observations and compare our approach with two baseline methods that use standard statistics. The baseline techniques are sensitive to the choice of thresholds, whereas our algorithm automatically estimates the appropriate model parameters and compares favorably with the best baseline results. This suggests the promise of our approach for pre-surgical planning in epilepsy.

  12. Digital Printing Quality Detection and Analysis Technology Based on CCD

    Science.gov (United States)

    He, Ming; Zheng, Liping

    2017-12-01

    With the help of CCD digital printing quality detection and analysis technology, it can carry out rapid evaluation and objective detection of printing quality, and can play a certain control effect on printing quality. It can be said CDD digital printing quality testing and analysis of the rational application of technology, its digital printing and printing materials for a variety of printing equipments to improve the quality of a very positive role. In this paper, we do an in-depth study and discussion based on the CCD digital print quality testing and analysis technology.

  13. Detection of unexploded ordnance by PGNAA based borehole-logging

    International Nuclear Information System (INIS)

    John Kettler; RWTH-Aachen University, Aachen; Eric Mauerhofer; Marco Steinbusch

    2013-01-01

    The performance of a borehole-logging system, based on prompt-gamma-neutron-activation-analysis (PGNAA), for explosive detection was studied by Monte-Carlo simulations. The prompt gamma of nitrogen, which is a constituent of common explosive, was used to identify the unexploded ordnance (UXO). Our results show that the minimum counting time depends on the soil moisture, the cladding thickness and the explosive composition. In conjunction with the standard detection by magnetometry, the PGNAA is a promising analytical technique for definitive identification of deep buried UXOs. (author)

  14. Developing a driving simulator based functional object detection task.

    Science.gov (United States)

    Goodenough, Richard R; Brooks, Johnell O; Crisler, Matthew C; Rosopa, Patrick J

    2012-10-01

    The purpose of this study was to validate a driving simulator-based tool for assessing functional visual scanning while driving (Goodenough, 2010) by replicating a previous study and assessing whether the results of the task are moderated by strategic decisions regarding task prioritization. Participants completed a functional object detection task that includes a peripheral target detection task and a central braking response task. Results indicated that the simulator task can identify differences in older and younger participants' abilities to functionally scan the driving environment and these differences appear unaffected by prioritizing either the scanning or braking task. Implications are discussed.

  15. A novel interacting multiple model based network intrusion detection scheme

    Science.gov (United States)

    Xin, Ruichi; Venkatasubramanian, Vijay; Leung, Henry

    2006-04-01

    In today's information age, information and network security are of primary importance to any organization. Network intrusion is a serious threat to security of computers and data networks. In internet protocol (IP) based network, intrusions originate in different kinds of packets/messages contained in the open system interconnection (OSI) layer 3 or higher layers. Network intrusion detection and prevention systems observe the layer 3 packets (or layer 4 to 7 messages) to screen for intrusions and security threats. Signature based methods use a pre-existing database that document intrusion patterns as perceived in the layer 3 to 7 protocol traffics and match the incoming traffic for potential intrusion attacks. Alternately, network traffic data can be modeled and any huge anomaly from the established traffic pattern can be detected as network intrusion. The latter method, also known as anomaly based detection is gaining popularity for its versatility in learning new patterns and discovering new attacks. It is apparent that for a reliable performance, an accurate model of the network data needs to be established. In this paper, we illustrate using collected data that network traffic is seldom stationary. We propose the use of multiple models to accurately represent the traffic data. The improvement in reliability of the proposed model is verified by measuring the detection and false alarm rates on several datasets.

  16. Contour Detection for UAV-Based Cadastral Mapping

    Directory of Open Access Journals (Sweden)

    Sophie Crommelinck

    2017-02-01

    Full Text Available Unmanned aerial vehicles (UAVs provide a flexible and low-cost solution for the acquisition of high-resolution data. The potential of high-resolution UAV imagery to create and update cadastral maps is being increasingly investigated. Existing procedures generally involve substantial fieldwork and many manual processes. Arguably, multiple parts of UAV-based cadastral mapping workflows could be automated. Specifically, as many cadastral boundaries coincide with visible boundaries, they could be extracted automatically using image analysis methods. This study investigates the transferability of gPb contour detection, a state-of-the-art computer vision method, to remotely sensed UAV images and UAV-based cadastral mapping. Results show that the approach is transferable to UAV data and automated cadastral mapping: object contours are comprehensively detected at completeness and correctness rates of up to 80%. The detection quality is optimal when the entire scene is covered with one orthoimage, due to the global optimization of gPb contour detection. However, a balance between high completeness and correctness is hard to achieve, so a combination with area-based segmentation and further object knowledge is proposed. The localization quality exhibits the usual dependency on ground resolution. The approach has the potential to accelerate the process of general boundary delineation during the creation and updating of cadastral maps.

  17. A New Acoustic Emission Sensor Based Gear Fault Detection Approach

    Directory of Open Access Journals (Sweden)

    Junda Zhu

    2013-01-01

    Full Text Available In order to reduce wind energy costs, prognostics and health management (PHM of wind turbine is needed to ensure the reliability and availability of wind turbines. A gearbox is an important component of a wind turbine. Therefore, developing effective gearbox fault detection tools is important to the PHM of wind turbine. In this paper, a new acoustic emission (AE sensor based gear fault detection approach is presented. This approach combines a heterodyne based frequency reduction technique with time synchronous average (TSA and spectrum kurtosis (SK to process AE sensor signals and extract features as condition indictors for gear fault detection. Heterodyne technique commonly used in communication is first employed to preprocess the AE signals before sampling. By heterodyning, the AE signal frequency is down shifted from several hundred kHz to below 50 kHz. This reduced AE signal sampling rate is comparable to that of vibration signals. The presented approach is validated using seeded gear tooth crack fault tests on a notational split torque gearbox. The approach presented in this paper is physics based and the validation results have showed that it could effectively detect the gear faults.

  18. A machine vision based approach for timber knots detection

    Science.gov (United States)

    Hittawe, Mohamad Mazen; Sidibé, Désiré; Mériaudeau, Fabrice

    2015-04-01

    Wood singularities detection is a primary step in wood grading enhancement. Our approach is purely machine vision based. The main objective is to compute physical properties like density, modulus of elasticity (MOE) and modulus of rupture (MOR) given wood surface images. Knots are one of the main singularities which directly affect the wood strength. Hence, our target is to detect knots and classify them into transverse and non-transverse ones. Then the Knots Depth Ratio (KDR) is computed based on all found transverse knots. Afterwards, KDR is used for the wood mechanical model improvement. Our technique is based on colour image analysis where the knots are detected by means of contrast intensity transformation and morphological operations. Then KDR computations are based on transverse knots and clear wood densities. Finally, MOE and MOR are computed using KDR images. The accuracy of number of knots found, their locations, MOE and MOR has been validated using a dataset of 252 images. In our dataset, these values were manually calculated. To the best of our knowledge our approach is the first purely machine vision based method to compute KDR, MOE and MOR.

  19. Ground-based Nuclear Detonation Detection (GNDD) Technology Roadmap

    International Nuclear Information System (INIS)

    Casey, Leslie A.

    2014-01-01

    This GNDD Technology Roadmap is intended to provide guidance to potential researchers and help management define research priorities to achieve technology advancements for ground-based nuclear explosion monitoring science being pursued by the Ground-based Nuclear Detonation Detection (GNDD) Team within the Office of Nuclear Detonation Detection in the National Nuclear Security Administration (NNSA) of the U.S. Department of Energy (DOE). Four science-based elements were selected to encompass the entire scope of nuclear monitoring research and development (R&D) necessary to facilitate breakthrough scientific results, as well as deliver impactful products. Promising future R&D is delineated including dual use associated with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Important research themes as well as associated metrics are identified along with a progression of accomplishments, represented by a selected bibliography, that are precursors to major improvements to nuclear explosion monitoring.

  20. Ground-based Nuclear Detonation Detection (GNDD) Technology Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Casey, Leslie A.

    2014-01-13

    This GNDD Technology Roadmap is intended to provide guidance to potential researchers and help management define research priorities to achieve technology advancements for ground-based nuclear explosion monitoring science being pursued by the Ground-based Nuclear Detonation Detection (GNDD) Team within the Office of Nuclear Detonation Detection in the National Nuclear Security Administration (NNSA) of the U.S. Department of Energy (DOE). Four science-based elements were selected to encompass the entire scope of nuclear monitoring research and development (R&D) necessary to facilitate breakthrough scientific results, as well as deliver impactful products. Promising future R&D is delineated including dual use associated with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Important research themes as well as associated metrics are identified along with a progression of accomplishments, represented by a selected bibliography, that are precursors to major improvements to nuclear explosion monitoring.

  1. Caries detection using light-based diagnostic tools.

    Science.gov (United States)

    Rechmann, Peter; Rechmann, Beate M T; Featherstone, John D B

    2012-09-01

    Modern caries treatment concepts like caries management by risk assessment--CAMBRA--entail diagnosing early caries lesions in a precavitated stage to make it possible to reverse the caries process with remineralization and bacteria reduction efforts. Newer, sensitive caries diagnostic tools can serve not only for early detection but also for monitoring of caries lesions to confirm the success of prevention and remineralization efforts. This article describes light-based caries diagnostic tools, with emphasis on fluorescence-based techniques, and compares the most common available fluorescence-based tools with a standardized visual caries inspection system-the International Caries Detection and Assessment System (ICDAS II). Fluorescence tools that provide high-resolution fluorescence pictures are likely to provide more reliable scores than fluorescence devices that assess via a single spot. The better visibility of the high-resolution fluorescence imaging could prevent unnecessary operative interventions.

  2. Detecting peripheral-based attacks on the host memory

    CERN Document Server

    Stewin, Patrick

    2015-01-01

    This work addresses stealthy peripheral-based attacks on host computers and presents a new approach to detecting them. Peripherals can be regarded as separate systems that have a dedicated processor and dedicated runtime memory to handle their tasks. The book addresses the problem that peripherals generally communicate with the host via the host’s main memory, storing cryptographic keys, passwords, opened files and other sensitive data in the process – an aspect attackers are quick to exploit.  Here, stealthy malicious software based on isolated micro-controllers is implemented to conduct an attack analysis, the results of which provide the basis for developing a novel runtime detector. The detector reveals stealthy peripheral-based attacks on the host’s main memory by exploiting certain hardware properties, while a permanent and resource-efficient measurement strategy ensures that the detector is also capable of detecting transient attacks, which can otherwise succeed when the applied strategy only me...

  3. Automated seismic detection of landslides at regional scales: a Random Forest based detection algorithm

    Science.gov (United States)

    Hibert, C.; Michéa, D.; Provost, F.; Malet, J. P.; Geertsema, M.

    2017-12-01

    Detection of landslide occurrences and measurement of their dynamics properties during run-out is a high research priority but a logistical and technical challenge. Seismology has started to help in several important ways. Taking advantage of the densification of global, regional and local networks of broadband seismic stations, recent advances now permit the seismic detection and location of landslides in near-real-time. This seismic detection could potentially greatly increase the spatio-temporal resolution at which we study landslides triggering, which is critical to better understand the influence of external forcings such as rainfalls and earthquakes. However, detecting automatically seismic signals generated by landslides still represents a challenge, especially for events with small mass. The low signal-to-noise ratio classically observed for landslide-generated seismic signals and the difficulty to discriminate these signals from those generated by regional earthquakes or anthropogenic and natural noises are some of the obstacles that have to be circumvented. We present a new method for automatically constructing instrumental landslide catalogues from continuous seismic data. We developed a robust and versatile solution, which can be implemented in any context where a seismic detection of landslides or other mass movements is relevant. The method is based on a spectral detection of the seismic signals and the identification of the sources with a Random Forest machine learning algorithm. The spectral detection allows detecting signals with low signal-to-noise ratio, while the Random Forest algorithm achieve a high rate of positive identification of the seismic signals generated by landslides and other seismic sources. The processing chain is implemented to work in a High Performance Computers centre which permits to explore years of continuous seismic data rapidly. We present here the preliminary results of the application of this processing chain for years

  4. A portable cell-based optical detection device for rapid detection of Listeria and Bacillus toxins

    Science.gov (United States)

    Banerjee, Pratik; Banada, Padmapriya P.; Rickus, Jenna L.; Morgan, Mark T.; Bhunia, Arun K.

    2005-11-01

    A mammalian cell-based optical biosensor was built to detect pathogenic Listeria and Bacillus species. This sensor measures the ability of the pathogens to infect and induce cytotoxicity on hybrid lymphocyte cell line (Ped-2E9) resulting in the release of alkaline phosphatase (ALP) that can be detected optically using a portable spectrophotometer. The Ped-2E9 cells were encapsulated in collagen gel matrices and grown in 48-well plates or in specially designed filtration tube units. Toxin preparations or bacterial cells were introduced and ALP release was assayed after 3-5 h. Pathogenic L. monocytogenes strains or the listeriolysin toxins preparation showed cytotoxicity ranging from 55% - 92%. Toxin preparations (~20 μg/ml) from B. cereus strains showed 24 - 98% cytotoxicity. In contrast, a non-pathogenic L. innocua (F4247) and a B. substilis induced only 2% and 8% cytotoxicity, respectively. This cell-based detection device demonstrates its ability to detect the presence of pathogenic Listeria and Bacillus species and can potentially be used onsite for food safety or in biosecurity application.

  5. Heteroduplex DNA mismatch repair system of Streptococcus pneumoniae: cloning and expression of the hexA gene

    International Nuclear Information System (INIS)

    Balganesh, T.S.; Lacks, S.A.

    1985-01-01

    Mutations affecting heteroduplex DNA mismatch repair in Streptococcus pneumoniae were localized in two genes, hexA and hexB, by fractionation of restriction fragments carrying mutant alleles. A fragment containing the hexA4 allele was cloned in the S. pneumoniae cloning system, and the hexA + allele was introduced into the recombinant plasmid by chromosomal facilitation of plasmid transfer. Subcloning localized the functional hexA gene to a 3.5-kilobase segment of the cloned pneumococcal DNA. The product of this gene was shown in Bacillus subtilis minicells to be a polypeptide with an M/sub r/ of 86,000. Two mutant alleles of hexA showed partial expression of the repair system when present in multicopy plasmids. A model for mismatch repair, which depends on the interaction of two protein components to recognize the mismatched base pair and excise a segment of DNA between strand breaks surrounding the mismatch, is proposed

  6. Parametric roll resonance monitoring using signal-based detection

    DEFF Research Database (Denmark)

    Galeazzi, Roberto; Blanke, Mogens; Falkenberg, Thomas

    2015-01-01

    Extreme roll motion of ships can be caused by several phenomena, one of which is parametric roll resonance. Several incidents occurred unexpectedly around the millennium and caused vast fiscal losses on large container vessels. The phenomenon is now well understood and some consider parametric roll...... algorithms in real conditions, and to evaluate the frequency of parametric roll events on the selected vessels. Detection performance is scrutinised through the validation of the detected events using owners’ standard methods, and supported by available wave radar data. Further, a bivariate statistical...... analysis of the outcome of the signal-based detectors is performed to assess the real life false alarm probability. It is shown that detection robustness and very low false warning rates are obtained. The study concludes that small parametric roll events are occurring, and that the proposed signal...

  7. Detection of underground pipeline based on Golay waveform design

    Science.gov (United States)

    Dai, Jingjing; Xu, Dazhuan

    2017-08-01

    The detection of underground pipeline is an important problem in the development of the city, but the research about it is not mature at present. In this paper, based on the principle of waveform design in wireless communication, we design an acoustic signal detection system to detect the location of underground pipelines. According to the principle of acoustic localization, we chose DSP-F28335 as the development board, and use DA and AD module as the master control chip. The DA module uses complementary Golay sequence as emission signal. The AD module acquisiting data synchronously, so that the echo signals which containing position information of the target is recovered through the signal processing. The test result shows that the method in this paper can not only calculate the sound velocity of the soil, but also can locate the location of underground pipelines accurately.

  8. Model-Based Design of Tree WSNs for Decentralized Detection

    Directory of Open Access Journals (Sweden)

    Ashraf Tantawy

    2015-08-01

    Full Text Available The classical decentralized detection problem of finding the optimal decision rules at the sensor and fusion center, as well as variants that introduce physical channel impairments have been studied extensively in the literature. The deployment of WSNs in decentralized detection applications brings new challenges to the field. Protocols for different communication layers have to be co-designed to optimize the detection performance. In this paper, we consider the communication network design problem for a tree WSN. We pursue a system-level approach where a complete model for the system is developed that captures the interactions between different layers, as well as different sensor quality measures. For network optimization, we propose a hierarchical optimization algorithm that lends itself to the tree structure, requiring only local network information. The proposed design approach shows superior performance over several contentionless and contention-based network design approaches.

  9. Multimodal Detection of Music Performances for Intelligent Emotion Based Lighting

    DEFF Research Database (Denmark)

    Bonde, Esben Oxholm Skjødt; Hansen, Ellen Kathrine; Triantafyllidis, Georgios

    2016-01-01

    . Using a microphone and a Kinect camera to detect such cues, the system is able to detect the intended emotion of what is being played. Specific lighting designs are then developed to support the specific emotions and the system is able to change between and alter the lighting design based......Playing music is about conveying emotions and the lighting at a concert can help do that. However, new and unknown bands that play at smaller venues and bands that don’t have the budget to hire a dedicated light technician have to miss out on lighting that will help them to convey the emotions...... of what they play. In this paper it is investigated whether it is possible or not to develop an intelligent system that through a multimodal input detects the intended emotions of the played music and in realtime adjusts the lighting accordingly. A concept for such an intelligent lighting system...

  10. Design of Gear Defect Detection System Based on Machine Vision

    Science.gov (United States)

    Wang, Yu; Wu, Zhiheng; Duan, Xianyun; Tong, Jigang; Li, Ping; Chen, min; Lin, Qinglin

    2018-01-01

    In order to solve such problems as low efficiency, low quality and instability of gear surface defect detection, we designed a detection system based on machine vision, sensor coupling. By multisensory coupling, and then CCD camera image collection of gear products, using VS2010 to cooperate with Halcon library for a series of analysis and processing of images. At last, the results are fed back to the control end, and the rejected device is removed to the collecting box. The system has successfully identified defective gear. The test results show that this system can identify and eliminate the defects gear quickly and efficiently. It has reached the requirement of gear product defect detection line automation and has a certain application value.

  11. ROS-based ground stereo vision detection: implementation and experiments.

    Science.gov (United States)

    Hu, Tianjiang; Zhao, Boxin; Tang, Dengqing; Zhang, Daibing; Kong, Weiwei; Shen, Lincheng

    This article concentrates on open-source implementation on flying object detection in cluttered scenes. It is of significance for ground stereo-aided autonomous landing of unmanned aerial vehicles. The ground stereo vision guidance system is presented with details on system architecture and workflow. The Chan-Vese detection algorithm is further considered and implemented in the robot operating systems (ROS) environment. A data-driven interactive scheme is developed to collect datasets for parameter tuning and performance evaluating. The flying vehicle outdoor experiments capture the stereo sequential images dataset and record the simultaneous data from pan-and-tilt unit, onboard sensors and differential GPS. Experimental results by using the collected dataset validate the effectiveness of the published ROS-based detection algorithm.

  12. Clone Detection for Graph-Based Model Transformation Languages

    DEFF Research Database (Denmark)

    Strüber, Daniel; Plöger, Jennifer; Acretoaie, Vlad

    2016-01-01

    Cloning is a convenient mechanism to enable reuse across and within software artifacts. On the downside, it is also a practice related to significant long-term maintainability impediments, thus generating a need to identify clones in affected artifacts. A large variety of clone detection techniques...... has been proposed for programming and modeling languages; yet no specific ones have emerged for model transformation languages. In this paper, we explore clone detection for graph-based model transformation languages. We introduce potential use cases for such techniques in the context of constructive...... and analytical quality assurance. From these use cases, we derive a set of key requirements. We describe our customization of existing model clone detection techniques allowing us to address these requirements. Finally, we provide an experimental evaluation, indicating that our customization of ConQAT, one...

  13. Topological sensitivity based far-field detection of elastic inclusions

    Science.gov (United States)

    Abbas, Tasawar; Khan, Shujaat; Sajid, Muhammad; Wahab, Abdul; Ye, Jong Chul

    2018-03-01

    The aim of this article is to present and rigorously analyze topological sensitivity based algorithms for detection of diametrically small inclusions in an isotropic homogeneous elastic formation using single and multiple measurements of the far-field scattering amplitudes. A L2 -cost functional is considered and a location indicator is constructed from its topological derivative. The performance of the indicator is analyzed in terms of the topological sensitivity for location detection and stability with respect to measurement and medium noises. It is established that the location indicator does not guarantee inclusion detection and achieves only a low resolution when there is mode-conversion in an elastic formation. Accordingly, a weighted location indicator is designed to tackle the mode-conversion phenomenon. It is substantiated that the weighted function renders the location of an inclusion stably with resolution as per Rayleigh criterion.

  14. Observer Based Detection of Sensor Faults in Wind Turbines

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob; Nielsen, R.

    2009-01-01

    An observer based scheme is proposed to detect sensor faults in wind  turbines. In the example used for the proposed scheme the wind turbine  drive train is considered. A model of the drive train is used to  design the observer, and in this model the wind speed is an important  input, however......, if an unknown input observer the fault detection  scheme can be non dependent on the actual wind speed. The scheme  is validated on data from a more advanced and detailed simulation  model. The proposed scheme detects the sensor faults a few samples  after the beginning of the faults....

  15. Scale Mismatches in Management of Urban Landscapes

    Directory of Open Access Journals (Sweden)

    Sara T. Borgström

    2006-12-01

    Full Text Available Urban landscapes constitute the future environment for most of the world's human population. An increased understanding of the urbanization process and of the effects of urbanization at multiple scales is, therefore, key to ensuring human well-being. In many conventional natural resource management regimes, incomplete knowledge of ecosystem dynamics and institutional constraints often leads to institutional management frameworks that do not match the scale of ecological patterns and processes. In this paper, we argue that scale mismatches are particularly pronounced in urban landscapes. Urban green spaces provide numerous important ecosystem services to urban citizens, and the management of these urban green spaces, including recognition of scales, is crucial to the well-being of the citizens. From a qualitative study of the current management practices in five urban green spaces within the Greater Stockholm Metropolitan Area, Sweden, we found that 1 several spatial, temporal, and functional scales are recognized, but the cross-scale interactions are often neglected, and 2 spatial and temporal meso-scales are seldom given priority. One potential effect of the neglect of ecological cross-scale interactions in these highly fragmented landscapes is a gradual reduction in the capacity of the ecosystems to provide ecosystem services. Two important strategies for overcoming urban scale mismatches are suggested: 1 development of an integrative view of the whole urban social-ecological landscape, and 2 creation of adaptive governance systems to support practical management.

  16. Possible roles for mismatch negativity in neuropsychiatry.

    Science.gov (United States)

    Gené-Cos, N; Ring, H A; Pottinger, R C; Barrett, G

    1999-01-01

    This article reviews research on the main characteristics of mismatch negativity (MMN) and its applications in neuropsychiatry. Event-related potentials (ERPs) have been used to study many aspects of information processing. Mismatch negativity is an early auditory ERP that has been identified as an index of an automatic (preconscious) alerting mechanism stimulating an individual to attend to unexpected environmental events. Disturbances of MMN may relate to abnormalities of auditory information processing contributing to the pathophysiology of neuropsychiatric conditions. The authors review (1) studies that have evaluated the electrophysiological aspects of MMN and (2) studies that have investigated the different applications of MMN in neuropsychiatry. The first part of this article describes the characteristics of MMN, its cerebral origins, and electrophysiological parameters. We then discuss the role of "echoic memory" as well as that of attention and vigilance. In the second part of the article, disturbances in MMN associated with schizophrenia, depressive illness, dementing processes, and other neuropsychiatric states are discussed. MMN is a preconscious cognitive ERP, the main generators and functions of which are well defined. Observations relating to the origins of MMN and its role in early auditory information processing together with its possible behavioral significance, combined with observations of MMN aberrations in psychiatric conditions, may provide novel insights into the pathophysiology of neuropsychiatric states.

  17. Skill mismatch and use in developed countries: Evidence from the PIAAC study

    NARCIS (Netherlands)

    Allen, J.P.; Levels, M.; van der Velden, R.K.W.

    2013-01-01

    In this paper we develop and test a new set of measures of skill mismatches, based on data on skill levels and skill use in the domains of literacy and numeracy from the PIAAC project. The measures we develop represent the extent of skill use relative to one’s own skill level. We test the measures

  18. Physiochemical disparity of mismatched HLA class I alloantigens and risk of acute GVHD following HSCT

    NARCIS (Netherlands)

    Kosmoliaptsis, V.; Joris, M. M.; Mallon, D. H.; Lankester, A. C.; von dem Borne, P. A.; Kuball, J.; Bierings, M.; Cornelissen, J. J.; Groenendijk-Sijnke, M. E.; van der Holt, B.; Bradley, J. A.; Oudshoorn, M.; van Rood, J. J.; Taylor, C. J.; Claas, F. H. J.

    We determined whether assessment of the immunogenicity of individual donor-recipient HLA mismatches based on differences in their amino-acid sequence and physiochemical properties predicts clinical outcome following haematopoietic SCT (HSCT). We examined patients transplanted with 9/10 single HLA

  19. Skill mismatch and skill use in developed countries: Evidence from the PIAAC study

    NARCIS (Netherlands)

    Allen, J.P.; Levels, M.; van der Velden, R.K.W.

    2013-01-01

    In this paper we develop and test a new set of measures of skill mismatches, based on data on skill levels and skill use in the domains of literacy and numeracy from the PIAAC project. The measures we develop represent the extent of skill use relative to one’s own skill level. We test the measures

  20. Labour Market Mismatch among UK Graduates: An Analysis Using REFLEX Data

    Science.gov (United States)

    McGuinness, Seamus; Sloane, Peter J.

    2011-01-01

    There is much disagreement in the literature over the extent to which graduates are mismatched in the labour market and the reasons for this. In this paper we utilise the Flexible Professional in the Knowledge Society (REFLEX) data set to cast light on these issues, based on data for UK graduates. We find substantial pay penalties for…

  1. Power System Transient Diagnostics Based on Novel Traveling Wave Detection

    Science.gov (United States)

    Hamidi, Reza Jalilzadeh

    Modern electrical power systems demand novel diagnostic approaches to enhancing the system resiliency by improving the state-of-the-art algorithms. The proliferation of high-voltage optical transducers and high time-resolution measurements provide opportunities to develop novel diagnostic methods of very fast transients in power systems. At the same time, emerging complex configuration, such as multi-terminal hybrid transmission systems, limits the applications of the traditional diagnostic methods, especially in fault location and health monitoring. The impedance-based fault-location methods are inefficient for cross-bounded cables, which are widely used for connection of offshore wind farms to the main grid. Thus, this dissertation first presents a novel traveling wave-based fault-location method for hybrid multi-terminal transmission systems. The proposed method utilizes time-synchronized high-sampling voltage measurements. The traveling wave arrival times (ATs) are detected by observation of the squares of wavelet transformation coefficients. Using the ATs, an over-determined set of linear equations are developed for noise reduction, and consequently, the faulty segment is determined based on the characteristics of the provided equation set. Then, the fault location is estimated. The accuracy and capabilities of the proposed fault location method are evaluated and also compared to the existing traveling-wave-based method for a wide range of fault parameters. In order to improve power systems stability, auto-reclosing (AR), single-phase auto-reclosing (SPAR), and adaptive single-phase auto-reclosing (ASPAR) methods have been developed with the final objectives of distinguishing between the transient and permanent faults to clear the transient faults without de-energization of the solid phases. However, the features of the electrical arcs (transient faults) are severely influenced by a number of random parameters, including the convection of the air and plasma

  2. Risk-based fault detection using Self-Organizing Map

    International Nuclear Information System (INIS)

    Yu, Hongyang; Khan, Faisal; Garaniya, Vikram

    2015-01-01

    The complexity of modern systems is increasing rapidly and the dominating relationships among system variables have become highly non-linear. This results in difficulty in the identification of a system's operating states. In turn, this difficulty affects the sensitivity of fault detection and imposes a challenge on ensuring the safety of operation. In recent years, Self-Organizing Maps has gained popularity in system monitoring as a robust non-linear dimensionality reduction tool. Self-Organizing Map is able to capture non-linear variations of the system. Therefore, it is sensitive to the change of a system's states leading to early detection of fault. In this paper, a new approach based on Self-Organizing Map is proposed to detect and assess the risk of fault. In addition, probabilistic analysis is applied to characterize the risk of fault into different levels according to the hazard potential to enable a refined monitoring of the system. The proposed approach is applied on two experimental systems. The results from both systems have shown high sensitivity of the proposed approach in detecting and identifying the root cause of faults. The refined monitoring facilitates the determination of the risk of fault and early deployment of remedial actions and safety measures to minimize the potential impact of fault. - Highlights: • A new approach based on Self-Organizing Map is proposed to detect faults. • Integration of fault detection with risk assessment methodology. • Fault risk characterization into different levels to enable focused system monitoring

  3. Magnetic Bead Based Immunoassay for Autonomous Detection of Toxins

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Y; Hara, C A; Knize, M G; Hwang, M H; Venkatesteswaran, K S; Wheeler, E K; Bell, P M; Renzi, R F; Fruetel, J A; Bailey, C G

    2008-05-01

    As a step towards toward the development of a rapid, reliable analyzer for bioagents in the environment, we are developing an automated system for the simultaneous detection of a group of select agents and toxins. To detect toxins, we modified and automated an antibody-based approach previously developed for manual medical diagnostics that uses fluorescent eTag{trademark} reporter molecules and is suitable for highly multiplexed assays. Detection is based on two antibodies binding simultaneously to a single antigen, one of which is labeled with biotin while the other is conjugated to a fluorescent eTag{trademark} through a cleavable linkage. Aqueous samples are incubated with the mixture of antibodies along with streptavidin-coated magnetic beads coupled to a photo-activatable porphyrin complex. In the presence of antigen, a molecular complex is formed where the cleavable linkage is held in proximity to the photoactivable group. Upon excitation at 680 nm, free radicals are generated, which diffuse and cleave the linkage, releasing the eTags{trademark}. Released eTags{trademark} are analyzed using capillary gel electrophoresis with laser-induced fluorescence detection. Limits of detection for ovalbumin and botulinum toxoid individually were 4 ng/mL (or 80 pg) and 16 ng/mL (or 320 pg), respectively, using the manual assay. In addition, we demonstrated the use of pairs of antibodies from different sources in a single assay to decrease the rate of false positives. Automation of the assay was demonstrated on a flow-through format with higher LODs of 125 ng/mL (or 2.5 ng) each of a mixture of ovalbumin and botulinum toxoid. This versatile assay can be easily modified with the appropriate antibodies to detect a wide range of toxins and other proteins.

  4. Object detection system based on multimodel saliency maps

    Science.gov (United States)

    Guo, Ya'nan; Luo, Chongfan; Ma, Yide

    2017-03-01

    Detection of visually salient image regions is extensively applied in computer vision and computer graphics, such as object detection, adaptive compression, and object recognition, but any single model always has its limitations to various images, so in our work, we establish a method based on multimodel saliency maps to detect the object, which intelligently absorbs the merits of various individual saliency detection models to achieve promising results. The method can be roughly divided into three steps: in the first step, we propose a decision-making system to evaluate saliency maps obtained by seven competitive methods and merely select the three most valuable saliency maps; in the second step, we introduce heterogeneous PCNN algorithm to obtain three prime foregrounds; and then a self-designed nonlinear fusion method is proposed to merge these saliency maps; at last, the adaptive improved and simplified PCNN model is used to detect the object. Our proposed method can constitute an object detection system for different occasions, which requires no training, is simple, and highly efficient. The proposed saliency fusion technique shows better performance over a broad range of images and enriches the applicability range by fusing different individual saliency models, this proposed system is worthy enough to be called a strong model. Moreover, the proposed adaptive improved SPCNN model is stemmed from the Eckhorn's neuron model, which is skilled in image segmentation because of its biological background, and in which all the parameters are adaptive to image information. We extensively appraise our algorithm on classical salient object detection database, and the experimental results demonstrate that the aggregation of saliency maps outperforms the best saliency model in all cases, yielding highest precision of 89.90%, better recall rates of 98.20%, greatest F-measure of 91.20%, and lowest mean absolute error value of 0.057, the value of proposed saliency evaluation

  5. Protein Microarrays-Based Strategies for Life Detection in Astrobiology

    Science.gov (United States)

    Parro, Víctor; Rivas, Luis A.; Gómez-Elvira, Javier

    2008-03-01

    The detection of organic molecules of unambiguous biological origin is fundamental for the confirmation of present or past life. Planetary exploration requires the development of miniaturized apparatus for in situ life detection. Analytical techniques based on mass spectrometry have been traditionally used in space science. Following the Viking landers, gas chromatography-mass spectrometry (GC-MS) for organic detection has gained general acceptance and has been used successfully in the Cassini-Huygens mission to Titan. Microfluidics allows the development of miniaturized capillary electrophoresis devices for the detection of important molecules for life, like amino acids or nucleobases. Recently, a new approach is gaining acceptance in the space science community: the application of the well-known, highly specific, antibody-antigen affinity interaction for the detection and identification of organics and biochemical compounds. Antibodies can specifically bind a plethora of structurally different compounds of a broad range of molecular sizes, from amino acids level to whole cells. Antibody microarray technology allows us to look for the presence of thousands of different compounds in a single assay and in just one square centimeter. Herein, we discuss several important issues—most of which are common with other instruments dealing with life signature detection in the solar system—that must be addressed in order to use antibody microarrays for life detection and planetary exploration. These issues include (1) preservation of biomarkers, (2) the extraction techniques for biomarkers, (3) terrestrial analogues, (4) the antibody stability under space environments, (5) the selection of unequivocal biomarkers for the antibody production, or (6) the instrument design and implementation.

  6. Hydrogel based QCM aptasensor for detection of avian influenza virus.

    Science.gov (United States)

    Wang, Ronghui; Li, Yanbin

    2013-04-15

    The objective of this study was to develop a quartz crystal microbalance (QCM) aptasensor based on ssDNA crosslinked polymeric hydrogel for rapid, sensitive and specific detection of avian influenza virus (AIV) H5N1. A selected aptamer with high affinity and specificity against AIV H5N1 surface protein was used, and hybridization between the aptamer and ssDNA formed the crosslinker in the polymer hydrogel. The aptamer hydrogel was immobilized on the gold surface of QCM sensor using a self-assembled monolayer method. The hydrogel remained in the state of shrink if no H5N1 virus was present in the sample because of the crosslinking between the aptamer and ssDNA in the polymer network. When it exposed to target virus, the binding reaction between the aptamer and H5N1 virus caused the dissolution of the linkage between the aptamer and ssDNA, resulting in the abrupt swelling of the hydrogel. The swollen hydrogel was monitored by the QCM sensor in terms of decreased frequency. Three polymeric hydrogels with different ratio (100:1 hydrogel I, 10:1 hydrogel II, 1:1 hydrogel III) of acrylamide and the aptamer monomer were synthesized, respectively, and then were used as the QCM sensor coating material. The results showed that the developed hydrogel QCM aptasensor was capable of detecting target H5N1 virus, and among the three developed aptamer hydrogels, hydrogel III coated QCM aptasensor achieved the highest sensitivity with the detection limit of 0.0128 HAU (HA unit). The total detection time from sampling to detection was only 30 min. In comparison with the anti-H5 antibody coated QCM immunosensor, the hydrogel QCM aptasensor lowered the detection limit and reduced the detection time. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Impact of Mismatch Angle on Electronic Transport Across Grain Boundaries and Interfaces in 2D Materials.

    Science.gov (United States)

    Majee, Arnab K; Foss, Cameron J; Aksamija, Zlatan

    2017-11-29

    We study the impact of grain boundaries (GB) and misorientation angles between grains on electronic transport in 2-dimensional materials. Here we have developed a numerical model based on the first-principles electronic bandstructure calculations in conjunction with a method which computes electron transmission coefficients from simultaneous conservation of energy and momentum at the interface to essentially evaluate GB/interface resistance in a Landauer formalism. We find that the resistance across graphene GBs vary over a wide range depending on misorientation angles and type of GBs, starting from 53 Ω μm for low-mismatch angles in twin (symmetric) GBs to about 10 20  Ω μm for 21° mismatch in tilt (asymmetric) GBs. On the other hand, misorientation angles have weak influence on the resistance across MoS 2 GBs, ranging from about 130 Ω μm for low mismatch angles to about 6000 Ω μm for 21°. The interface resistance across graphene-MoS 2 heterojunctions also exhibits a strong dependence on misorientation angles with resistance values ranging from about 100 Ω μm for low-mismatch angles in Class-I (symmetric) interfaces to 10 15  Ω μm for 14° mismatch in Class-II (asymmetric) interfaces. Overall, symmetric homo/heterojunctions exhibit a weak dependence on misorientation angles, while in MoS 2 both symmetric and asymmetric GBs show a gradual dependence on mismatch angles.

  8. The effect of angular mismatch between vertebral endplate and vertebral body replacement endplate on implant subsidence.

    Science.gov (United States)

    Mohammad-Shahi, Mohammad H; Nikolaou, Vassilios S; Giannitsios, Demetrios; Ouellet, Jean; Jarzem, Peter F

    2013-07-01

    Comparative biomechanical study. To determine whether an angular mismatch between the vertebral body replacement (VBR) endplate and the simulated foam vertebral endplate leads to accelerated subsidence in a cyclic compression model of the VBR-vertebra interface. One of the main complications of the VBR surgery is postoperative subsidence and collapse of the VBR implant into the adjacent vertebral bodies. Although numerous factors affecting intervertebral cage subsidence have been cited, few studies have proposed factors responsible for VBR cage subsidence. Hardwood blocks at 0-30-degree angles and polyurethane foam blocs have been used as base for this experimental setting. One end of the Synex (Synthes) expandable cage was attached to a material testing machine. The endplate of the implant was placed at a similar spot on the block in such a manner that there was an exact match between the Synex endplate and the foam block at 0 degrees, subsequent angled blocks would tilt the foam endplates by the 10-, 20-, and 30-degree increments as needed. Cyclic axial loads were applied in 9 load-unload cycles. Five samples were tested at each mismatch angle (0, 10, 20, and 30 degrees), for a total of 20 trials. Implant subsidence significantly increased for each 10-degree increase in mismatch angle. This effect, however, did not follow a uniform trend at all angles. The curve appeared exponential at 0 degree of angular mismatch, became linear at 10-20 degrees of mismatch, and then demonstrated some ability to resist load at 30 degrees, leading to a plateau at the higher loads. Increasing mismatch angles are an important factor in leading to increased cage subsidence into polyurethane blocks. Consequently, the incidence of subsidence in the clinical setting could be reduced by paying careful attention to ensuring that both the prosthetic and bony endplates are well apposed at the end of surgery.

  9. Single molecule transistor based nanopore for the detection of nicotine

    Science.gov (United States)

    Ray, S. J.

    2014-12-01

    A nanopore based detection methodology was proposed and investigated for the detection of Nicotine. This technique uses a Single Molecular Transistor working as a nanopore operational in the Coulomb Blockade regime. When the Nicotine molecule is pulled through the nanopore area surrounded by the Source(S), Drain (D), and Gate electrodes, the charge stability diagram can detect the presence of the molecule and is unique for a specific molecular structure. Due to the weak coupling between the different electrodes which is set by the nanopore size, the molecular energy states stay almost unaffected by the electrostatic environment that can be realised from the charge stability diagram. Identification of different orientation and position of the Nicotine molecule within the nanopore area can be made from specific regions of overlap between different charge states on the stability diagram that could be used as an electronic fingerprint for detection. This method could be advantageous and useful to detect the presence of Nicotine in smoke which is usually performed using chemical chromatography techniques.

  10. Single molecule transistor based nanopore for the detection of nicotine

    Energy Technology Data Exchange (ETDEWEB)

    Ray, S. J., E-mail: ray.sjr@gmail.com [Institute of Materials Science, Technical University of Darmstadt, Alarich-Weiss-Str. 2, 64287 Darmstadt (Germany)

    2014-12-28

    A nanopore based detection methodology was proposed and investigated for the detection of Nicotine. This technique uses a Single Molecular Transistor working as a nanopore operational in the Coulomb Blockade regime. When the Nicotine molecule is pulled through the nanopore area surrounded by the Source(S), Drain (D), and Gate electrodes, the charge stability diagram can detect the presence of the molecule and is unique for a specific molecular structure. Due to the weak coupling between the different electrodes which is set by the nanopore size, the molecular energy states stay almost unaffected by the electrostatic environment that can be realised from the charge stability diagram. Identification of different orientation and position of the Nicotine molecule within the nanopore area can be made from specific regions of overlap between different charge states on the stability diagram that could be used as an electronic fingerprint for detection. This method could be advantageous and useful to detect the presence of Nicotine in smoke which is usually performed using chemical chromatography techniques.

  11. An Automata Based Intrusion Detection Method for Internet of Things

    Directory of Open Access Journals (Sweden)

    Yulong Fu

    2017-01-01

    Full Text Available Internet of Things (IoT transforms network communication to Machine-to-Machine (M2M basis and provides open access and new services to citizens and companies. It extends the border of Internet and will be developed as one part of the future 5G networks. However, as the resources of IoT’s front devices are constrained, many security mechanisms are hard to be implemented to protect the IoT networks. Intrusion detection system (IDS is an efficient technique that can be used to detect the attackers when cryptography is broken, and it can be used to enforce the security of IoT networks. In this article, we analyzed the intrusion detection requirements of IoT networks and then proposed a uniform intrusion detection method for the vast heterogeneous IoT networks based on an automata model. The proposed method can detect and report the possible IoT attacks with three types: jam-attack, false-attack, and reply-attack automatically. We also design an experiment to verify the proposed IDS method and examine the attack of RADIUS application.

  12. Cortical dynamics of visual change detection based on sensory memory.

    Science.gov (United States)

    Urakawa, Tomokazu; Inui, Koji; Yamashiro, Koya; Tanaka, Emi; Kakigi, Ryusuke

    2010-08-01

    Detecting a visual change was suggested to relate closely to the visual sensory memory formed by visual stimuli before the occurrence of the change, because change detection involves identifying a difference between ongoing and preceding sensory conditions. Previous neuroimaging studies showed that an abrupt visual change activates the middle occipital gyrus (MOG). However, it still remains to be elucidated whether the MOG is related to visual change detection based on sensory memory. Here we tried to settle this issue using a new method of stimulation with blue and red LEDs to emphasize a memory-based change detection process. There were two stimuli, a standard trial stimulus and a deviant trial stimulus. The former was a red light lasting 500 ms, and the latter was a red light lasting 250 ms immediately followed by a blue light lasting 250 ms. Effects of the trial-trial interval, 250 approximately 2000 ms, were investigated to know how cortical responses to the abrupt change (from red to blue) were affected by preceding conditions. The brain response to the deviant trial stimulus was recorded by magnetoencephalography. Results of a multi-dipole analysis showed that the activity in the MOG, peaking at around 150 ms after the change onset, decreased in amplitude as the interval increased, but the earlier activity in BA 17/18 was not affected by the interval. These results suggested that the MOG is an important cortical area relating to the sensory memory-based visual change-detecting system. Copyright 2010 Elsevier Inc. All rights reserved.

  13. AdaBoost-based algorithm for network intrusion detection.

    Science.gov (United States)

    Hu, Weiming; Hu, Wei; Maybank, Steve

    2008-04-01

    Network intrusion detection aims at distinguishing the attacks on the Internet from normal use of the Internet. It is an indispensable part of the information security system. Due to the variety of network behaviors and the rapid development of attack fashions, it is necessary to develop fast machine-learning-based intrusion detection algorithms with high detection rates and low false-alarm rates. In this correspondence, we propose an intrusion detection algorithm based on the AdaBoost algorithm. In the algorithm, decision stumps are used as weak classifiers. The decision rules are provided for both categorical and continuous features. By combining the weak classifiers for continuous features and the weak classifiers for categorical features into a strong classifier, the relations between these two different types of features are handled naturally, without any forced conversions between continuous and categorical features. Adaptable initial weights and a simple strategy for avoiding overfitting are adopted to improve the performance of the algorithm. Experimental results show that our algorithm has low computational complexity and error rates, as compared with algorithms of higher computational complexity, as tested on the benchmark sample data.

  14. A novel duplicate images detection method based on PLSA model

    Science.gov (United States)

    Liao, Xiaofeng; Wang, Yongji; Ding, Liping; Gu, Jian

    2012-01-01

    Web image search results usually contain duplicate copies. This paper considers the problem of detecting and clustering duplicate images contained in web image search results. Detecting and clustering the duplicate images together facilitates users' viewing. A novel method is presented in this paper to detect and cluster duplicate images by measuring similarity between their topics. More specifically, images are viewed as documents consisting of visual words formed by vector quantizing the affine invariant visual features. Then a statistical model widely used in text domain, the PLSA(Probabilistic Latent Semantic Analysis) model, is utilized to map images into a probabilistic latent semantic space. Because the main content remains unchanged despite small digital alteration, duplicate images will be close to each other in the derived semantic space. Based on this, a simple clustering process can successfully detect duplicate images and cluster them together. Comparing to those methods based on comparison between hash value of visual words, this method is more robust to the visual feature level alteration posed on the images. Experiments demonstrates the effectiveness of this method.

  15. Detection of rail corrugation based on fiber laser accelerometers

    International Nuclear Information System (INIS)

    Huang, Wenzhu; Zhang, Wentao; Li, Fang; Du, Yanliang; Sun, Baochen; Ma, Huaixiang

    2013-01-01

    Efficient inspection methods are necessary for detection of rail corrugation to improve the safety and ride quality of railway operations. This paper presents a novel fiber optic technology for detection of rail corrugation based on fiber laser accelerometers (FLAs), tailored to the measurement of surface damage on rail structures. The principle of detection of rail corrugation using double integration of axle-box acceleration is presented. Then we present the theoretical model and test results of FLAs which are installed on the bogie to detect the vertical axle-box acceleration of the train. Characteristics of high sensitivity and large dynamic range are achieved when using fiber optic interferometric demodulation. A flexible inertial algorithm based on double integration and the wavelet denoising method is proposed to accurately estimate the rail corrugation. A field test is carried out on the Datong–Qinhuangdao Railway in north China. The test results are compared with the results of a rail inspection car, which shows that the fiber laser sensing system has a good performance in monitoring rail corrugation. (paper)

  16. Shadow-Based Vehicle Detection in Urban Traffic

    Directory of Open Access Journals (Sweden)

    Manuel Ibarra-Arenado

    2017-04-01

    Full Text Available Vehicle detection is a fundamental task in Forward Collision Avoiding Systems (FACS. Generally, vision-based vehicle detection methods consist of two stages: hypotheses generation and hypotheses verification. In this paper, we focus on the former, presenting a feature-based method for on-road vehicle detection in urban traffic. Hypotheses for vehicle candidates are generated according to the shadow under the vehicles by comparing pixel properties across the vertical intensity gradients caused by shadows on the road, and followed by intensity thresholding and morphological discrimination. Unlike methods that identify the shadow under a vehicle as a road region with intensity smaller than a coarse lower bound of the intensity for road, the thresholding strategy we propose determines a coarse upper bound of the intensity for shadow which reduces false positives rates. The experimental results are promising in terms of detection performance and robustness in day time under different weather conditions and cluttered scenarios to enable validation for the first stage of a complete FACS.

  17. Drunk driving detection based on classification of multivariate time series.

    Science.gov (United States)

    Li, Zhenlong; Jin, Xue; Zhao, Xiaohua

    2015-09-01

    This paper addresses the problem of detecting drunk driving based on classification of multivariate time series. First, driving performance measures were collected from a test in a driving simulator located in the Traffic Research Center, Beijing University of Technology. Lateral position and steering angle were used to detect drunk driving. Second, multivariate time series analysis was performed to extract the features. A piecewise linear representation was used to represent multivariate time series. A bottom-up algorithm was then employed to separate multivariate time series. The slope and time interval of each segment were extracted as the features for classification. Third, a support vector machine classifier was used to classify driver's state into two classes (normal or drunk) according to the extracted features. The proposed approach achieved an accuracy of 80.0%. Drunk driving detection based on the analysis of multivariate time series is feasible and effective. The approach has implications for drunk driving detection. Copyright © 2015 Elsevier Ltd and National Safety Council. All rights reserved.

  18. Variable selection based cotton bollworm odor spectroscopic detection

    Science.gov (United States)

    Lü, Chengxu; Gai, Shasha; Luo, Min; Zhao, Bo

    2016-10-01

    Aiming at rapid automatic pest detection based efficient and targeting pesticide application and shooting the trouble of reflectance spectral signal covered and attenuated by the solid plant, the possibility of near infrared spectroscopy (NIRS) detection on cotton bollworm odor is studied. Three cotton bollworm odor samples and 3 blank air gas samples were prepared. Different concentrations of cotton bollworm odor were prepared by mixing the above gas samples, resulting a calibration group of 62 samples and a validation group of 31 samples. Spectral collection system includes light source, optical fiber, sample chamber, spectrometer. Spectra were pretreated by baseline correction, modeled with partial least squares (PLS), and optimized by genetic algorithm (GA) and competitive adaptive reweighted sampling (CARS). Minor counts differences are found among spectra of different cotton bollworm odor concentrations. PLS model of all the variables was built presenting RMSEV of 14 and RV2 of 0.89, its theory basis is insect volatilizes specific odor, including pheromone and allelochemics, which are used for intra-specific and inter-specific communication and could be detected by NIR spectroscopy. 28 sensitive variables are selected by GA, presenting the model performance of RMSEV of 14 and RV2 of 0.90. Comparably, 8 sensitive variables are selected by CARS, presenting the model performance of RMSEV of 13 and RV2 of 0.92. CARS model employs only 1.5% variables presenting smaller error than that of all variable. Odor gas based NIR technique shows the potential for cotton bollworm detection.

  19. Fault detection and reliability, knowledge based and other approaches

    International Nuclear Information System (INIS)

    Singh, M.G.; Hindi, K.S.; Tzafestas, S.G.

    1987-01-01

    These proceedings are split up into four major parts in order to reflect the most significant aspects of reliability and fault detection as viewed at present. The first part deals with knowledge-based systems and comprises eleven contributions from leading experts in the field. The emphasis here is primarily on the use of artificial intelligence, expert systems and other knowledge-based systems for fault detection and reliability. The second part is devoted to fault detection of technological systems and comprises thirteen contributions dealing with applications of fault detection techniques to various technological systems such as gas networks, electric power systems, nuclear reactors and assembly cells. The third part of the proceedings, which consists of seven contributions, treats robust, fault tolerant and intelligent controllers and covers methodological issues as well as several applications ranging from nuclear power plants to industrial robots to steel grinding. The fourth part treats fault tolerant digital techniques and comprises five contributions. Two papers, one on reactor noise analysis, the other on reactor control system design, are indexed separately. (author)

  20. APTAMER-BASED SERRS SENSOR FOR THROMBIN DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Cho, H; Baker, B R; Wachsmann-Hogiu, S; Pagba, C V; Laurence, T A; Lane, S M; Lee, L P; Tok, J B

    2008-07-02

    We describe an aptamer-based Surface Enhanced Resonance Raman Scattering (SERRS) sensor with high sensitivity, specificity, and stability for the detection of a coagulation protein, human a-thrombin. The sensor achieves high sensitivity and a limit of detection of 100 pM by monitoring the SERRS signal change upon the single step of thrombin binding to immobilized thrombin binding aptamer. The selectivity of the sensor is demonstrated by the specific discrimination of thrombin from other protein analytes. The specific recognition and binding of thrombin by the thrombin binding aptamer is essential to the mechanism of the aptamer-based sensor, as shown through measurements using negative control oligonucleotides. In addition, the sensor can detect 1 nM thrombin in the presence of complex biofluids, such as 10% fetal calf serum, demonstrating that the immobilized, 5{prime}-capped, 3{prime}-capped aptamer is sufficiently robust for clinical diagnostic applications. Furthermore, the proposed sensor may be implemented for multiplexed detection using different aptamer-Raman probe complexes.